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ISCIS 2003 - Programme

[events] [talks] [abstracts]
November 3, 2003
8:30Registration
9:15Opening Remarks
9:30Invited Talk 1
    Zeus Hall : Invited Talk I
      Review of Experiments in Self-Aware Networks. Erol Gelenbe
        We show how "self-awareness", through on-lineself-monitoring and measurement, coupled with intelligent adaptivebehaviour in response to observed data, can be used to offer quality of service to networkusers based on the "Cognitive Packet Network" (CPN) design.
10:30Coffee Break
11:00Session 1
    Zeus Hall : Graphics & Computer Vision I
      Facial Expression Recognition based upon the Gabor-wavelets based Enhanced Fisher Model. Sung-Oh Lee, Yong-Guk Kim, Gwi-Tae Park
        This work deals with how the machine classifies human facial expressions, which has been a challenging problem for many researchers from the diverse areas. The facial expression recognition system mainly consists of two cascade stages: the representation method for the facial images at the front and the facial emotion classifier at the back. The Gabor-wavelets based method has shown promising performance because of its efficient representation and biological implication. Here we focus on the classification method to obtain high recognition rate of facial expressions. Results suggest that enhanced Fisher discrimination model, which had been used for the face recognition task, outperformed Principal Component Analysis (PCA) based classifier (or the neural network) with the 93% correction rate, when it is combined with the Gabor representation.
      Practical Gaze Detection by Auto Pan/Tilt Vision System. Kang Ryoung Park
        This paper presents a practical method for detecting the point in the monitor where a user gazes by moving his face and eyes. Previous gaze detection system uses a wide view camera, which can capture the whole face of user. In such case, the image resolution is so low that the fine movements of user's eye cannot be exactly detected and the accurate eye gaze position cannot be located consequently. So, we implement the gaze detection system with a wide view camera and a narrow view camera. Because the narrow view camera captures the eye image with high magnification, the eye position easily escapes from the narrow view camera by user's facial movements. For these reasons, we adopt the functionalities of auto focusing and auto panning/tilting into the narrow view camera and those are performed based on the information of the detected 3D facial feature positions by the wide view camera. As experimental results, our gaze detection system operates in real-time and the gaze detection accuracy between the computed positions and the real ones is about 3.57 cm of RMS error.
      License Plate Segmentation for Intelligent Transportation Systems. Muhammed Cinsdikici, Turhan Tunali
        A license plate segmentation system is designed and developed. The system has preprocessing, approximate region finding, pure plate segmentation and character segmentation modules. For each module, alternative available methods are examined and proper sequence of operations is developed. In character segmentation module a novel method is devised. Finally, overall performance of the system is reported.
      License Plate Character Segmentation Based on Gabor Transform and Vector Quantization. Fatih Kahraman, Binnur Kurt, Muhittin Gökmen
        This paper presents a novel algorithm for license-plate detection and localization problems by using Gabor transform in detection and local vector quantization in segmentation. As of our knowledge this is the first application of Gabor filters to license plate segmentation problem. Even though much of the research efforts are devoted to the edge or global thresholding-based approaches, it is more practical and efficient to analyze the image in certain directions and scales utilizing Gabor transform instead of error-prone edge detection or thresholding. Gabor filter response only gives a rough estimate of the plate boundary. Then binary split tree is used for vector quantization in order to extract the exact boundary and segment the plate region into disjoint characters which become ready for the optical character recognition
    Leto Hall : Networks and Security I
      Transport Protocol Mechanisms for Wireless Networking: A Review and Comparative Simulation Study. Alper Kanak, Oznur Ozkasap
        Increasing popularity of wireless services has triggered the need for efficient wireless transport mechanisms. TCP, being the reliable transport level protocol widely used in wired network world, was not designed with heterogeneity in mind. The problem with the adaptation of TCP to the evolving wireless settings is because of the assumption that packet loss and unusual delays are mainly caused by congestion. TCP originally assumes that packet loss is very small. On the other hand, wireless links often suffer from high bit error rates and broken connectivity due to handoffs. A range of schemes, namely end-to-end, split-connection and link-layer protocols, has been proposed to improve the performance of transport mechanisms, in particular TCP, on wireless settings. In this study, we examine these mechanisms for wireless transport, and discuss our comparative simulation results of end-to-end TCP versions (Tahoe, Reno, NewReno and SACK) in various network settings including wireless LANs and wired-cum-wireless scenarios.
      Network Level Congestion Control in Mobile Wireless Networks : 3G & beyond. Seungcheon Kim
        Abstract—The key problem that is expected in the future mobile wireless networks is related with the mobility effect on the network data traffic, which may cause the performance degradation and congestion. This paper explores the mobility effect on the delay and congestion when the future mobile wireless networks have become the whole IP based networks and introduces a network level congestion control based on the Explicit Congestion Notification (ECN) broadcasting in the wireless sub networks. The simulation results are provided to show the performance improvement when the proposed scheme’s adopted.
      An Efficient Location Area Design Scheme to Minimize Registration Signalling Traffic in Wireless Systems. Ümit Aslıhak and Feza Buzluca
        Abstract. In this paper, a new static traffic-based location area design scheme named ETB-LAD (enhanced TB-LAD) for wireless systems is proposed. This scheme is an enhancement on the previously published TB-LAD scheme. In the new method, the expected intercell movement patterns of mobiles are determined and then the cells are partitioned into location areas (LAs) by applying the new traffic-based cell grouping algorithm, which has two goals. First, the cell pairs with higher intercell mobile traffic are grouped into the same LA. Second, the LAs, in which the neighbour cells have higher intercell traffic, allowed to include more cells than the LAs, where the intercell traffic is low. The aim of the scheme is to decrement the inter-LA movements, which create registration traffic. Experimental results show that the new scheme performs better than the TB-LAD and proximity based location area design (PB-LAD) schemes in the sense that it can reduce the location updates.
      Multi-Threshold Guard Channel Policy for Next Generation Wireless Networks. Hamid Beigy and M. R. Meybodi
        In this paper, we consider the call admission problem in next generation wireless networks, which must handles multi-media traffics. We give an algorithm, which finds the optimal number of guard channels, which minimizes the overall blocking probability calls with lowest level of QoS in a multi-cell cellular network subject to the hard constraint on the blocking probabilities of other calls.
    Apollo Hall : Database and Information Retrieval I
      A Robust Scheme for Multilevel Extendible Hashing. Sven Helmer, Thomas Neumann, Guido Moerkotte
        Dynamic hashing, while surpassing other access methods for uniformly distributed data, usually performs badly for non-uniformly distributed data. We propose a robust scheme for multi-level extendible hashing, allowing efficient processing of skewed data as well as uniformly distributed data. In order to test our access method, we implemented it and compared it to several existing hashing schemes. The results of the experimental evaluation demonstrate the superiority of our approach in both index size and performance.
      Comparison of New Simple Weighting Functions for Web Documents Against Existing Methods. Byurhan Hyusein, Ahmed Patel, and Ferad Zyulkyarov
        Term weighting is one of the most important aspects of modern Web retrieval systems. The weight associated with a given term in a document shows the importance of the term for the document, i.e. its usefulness for distinguishing documents in a document collection. In search engines operating in a dynamic environment such as the Internet, where many documents are deleted from and added to the database, the usual formula involving the inverse document frequency is too costly to be computed each time the document collection is updated. This paper proposes two new simple and effective weighting functions. These weighting functions have been tested and compared with results obtained for the PIVOT, SMART and INQUERY methods using the WT10g collection of documents.
      A Flexible Querying Framework: some implementation issues. Bert Callens, Guy de Tré, Jörg Verstraete, Axel Hallez
        Flexible data are a common concept in today's information society. Some data can be unknown, other data may be inaccurate or uncertain. Still, this flexible data must be accounted for in modern businesses and therefore must be stored. Flexible relational databases have been studied extensively over time, which resulted in numerous models and representation techniques, some of which have been implemented as software layers on top of database systems. Different query languages and end-user interfaces have been extended to perform flexible queries on both regular and flexible databases. In this paper, a framework is presented that not only enables flexible querying on the relational model, but on other database models as well, of which the most important are object-oriented database models. This framework, called FQF or Flexible Querying Framework, is built on the recently developed Java Data Objects (JDO) standard.
      Stemming in Agglutinative Languages: A Probabilistic Stemmer For Turkish. B. Taner Dinçer, Bahar Karaoglan
        In this paper, we introduce a new lexicon free, probabilistic stemmer used in a developing Turkish Information Retrieval system. It has a linear computational complexity and its test success ratio is 95.8%. The main contribution of this paper is to give a thorough description of a probabilistic perspective for stemming which can also be generalized to apply to other agglutinative languages like Finnish, Hungarian, Estonian and Czech
    Artemis Hall : Architectures and Systems I
      KinCA: An InfiniBand Host Channel Adapter Based on Dual Processor Cores. Sangman Moh, Kyoung Park, and Sungnam Kim
        InfiniBand technology is being accepted as the future system interconnect to serve as the high-end enterprise fabric for cluster computing. This paper presents the design and implementation of an InfiniBand host channel adapter (HCA) based on dual ARM9 processor cores. The HCA is an SoC called KinCA which connects a host node onto the InfiniBand network both in hardware and in software. Since the ARM9 processor core does not provide necessary features for multiprocessor configuration, novel inter-processor communication and interrupt mechanisms between the two processors were designed and embedded within the KinCA chip. KinCA was fabricated as a 564-pin enhanced BGA (Ball Grid Array) device using 0.18mm CMOS technology. Mounted on host nodes, it provides 10 Gbps outbound and inbound channels for transmit and receive, respectively, enabling a high-performance cluster system.
      Fast Less Recursive Hardware for Large Number Multiplication Using Karatsuba-Ofman's. Nadia Nedjah, Luiza de Macedo Mourelle
        Multiplication of long integers is a cornerstone primitive in most cryptosystems. Multiplication for big numbers can be performed best using Karatsuba-Ofman's divide-and-conquer approach. Multiplying long integers using Karatsuba-Ofman's algorithm is fast but the algorithm is highly recursive. We propose a less recursive and efficient hardware architecture for this algorithm. We compare the proposed multiplier to other existing ones.
      Fast Hardware for Booth-Barrett’s Modular Multiplication for Efficient Cryptosystems. Nadia Nedjah, Luiza de Macedo Mourelle
        Modular multiplication is fundamental to several public-key cryptography systems such as the RSA encryption system. It is also the most dominant part of the computation performed in such systems. The operation is time consuming for large operands. This paper examines the characteristics of yet another architecture to implement modular multiplication. An experimental modular multiplier prototype is described in VHDL and simulated. The simulation results are presented.
      Conditional Access Module Systems for Digital Contents Protection Based on Hybrid-Fiber-Coax CATV Networks. Won Jay Song, Won Hee Kim, Bo Gwan Kim, Byung Ha Ahn, Munkee Choi, and Minho Kang
        In this paper, we have proposed the merging of the OpenCable reference model with the smart card interface defined by ISO/IEC 7816-3 and have implemented a new Conditional Access System (CAS) using this interface along with a Personal Computer Memory Card International Association (PCMCIA) interface. In addition, we have also designed the hardware architecture of the Point-of-Deployment (POD) security module, designed with the Verilog HDL, using the above two interfaces. The designed POD security module has an embedded 32-bit Reduced Instruction Set Computer (RISC) microprocessor that manages applications, such as an MPEG-2 filter, descrambler, and Data Encryption Standard (DES). We have tested this modeled and designed system using a prototype and show satisfactory simulation results.
12:30Lunch
14:00Invited Talk 2
    Zeus Hall : Invited Talk II
      Recent trends and applications in Computer Vision. Aytul Erçil
15:00Coffee Break
15:30Session 2
    Zeus Hall : Graphics & Computer Vision II
      Model-Based Human Motion Capture from Monocular Video Sequences. Jihun Park, Sangho Park, J. K. Aggarwal
        The generation of motion and motion capturing of an articulated body for computer animation is an expensive and time consuming task. Conventionally, animators manually generate intermediate frames between keyframes, but this task is very time consuming. This paper presents a new model-based singularity-free automatic-initialization approach to motion capturing of human motion video based on widely-available, static-background monocular video sequences. A 3D human body model is built and projected on a 2D projection plane to find best fitting with the foreground image silhouette. We convert the human motion capture problem into two types of parameter optimization problem: static optimization and dynamic optimization. First, we determine each model body configuration using static optimizations for every input image. Then, to get better motion, the results from all static optimizations are fed into a dynamic optimization process, where the entire sequence of motion is considered for the user-specified motion. The user-specified motion is defined by each user and the final form of the motion they want. A cost function for static optimization is used to estimate the degree of overlapping between the foreground input image silhouette and a projected 3D model body silhouette. The overlapping is computed using computational geometry by converting a set of pixels from the image domain to a polygon in the real projection plane domain. A cost function for dynamic optimization is the user-specified motion based on the static optimization results as well as image fitting. Our method is used to capture various human motions.
      Background Estimation Based People Detection and Tracking For Video Surveillance. Murat Ekinci, Eyüp Gedikli
        In this paper, real-time people detection and tracking using background modeling and maintenance technique for visual surveillanmce system in an indoor and an outdoor environments is described. The system operates on monocular grayscale video imagery from an static CCD camera. In order to detect foreground objects, firstly, background scene model is statistically learned using the redundancy of the pixel intensity values during learning stage, even the background is not completely stationary. This redundany information of the each pixel is separately stored in an history map shows how the pixel intensity values changes till now. Then the biggest ratio of the redundancy of the pixel intensity values in the history map during training sequence is determined to have initial background model of the scene. A background maintenance model is also proposed for preventing some kind of falses, such as, illumination changes (the sun being blocked by clouds causing changes in brightness), or physical changes (person detection while he is getting out or passing in front of the parked car). And then for people detection, candidate foreground regions are detected using thresholding, noise cleaning and their boundaries extracted using morphological filters. From these, a body posture is estimated depending on skeleton of the regions. Finaly, the trajectory of the people in motion is implemented for analysing the people actions tracked in the video sequences. Experimental results demonstrate robustness and real-time performance of the algorithm.
      Quaternion-based Tracking Multiple Objects in Synchronized Videos. Quming Zhou, Jihun Park, J. K. Aggarwal
        This paper presents a method for tracking multiple objects using multiple cameras that integrates spatial position, shape and color information to track object blobs. Given three known points on the ground, camera calibration are computed by solving a set of quaternion-based nonlinear functions rather than solving approximated linear functions. By using quaternion-based method, we can avoid singularity problem. Our method focuses on establishing correspondence between objects and templates as the objects come into view. We fuse the data from individual cameras using an Extended Kalman Filter (EKF) to resolve object occlusion. Our results show that integrating simple features makes the tracking effective, and that EKF improves the tracking accuracy when long term or temporary occlusion occurs. Experimental results are provided to demonstrate the effectiveness of the proposed method.
      Image Sequence Stabilization Using Membership Selective Fuzzy Filtering. M. Kemal Güllü, Sarp Ertürk
        Image sequence stabilization aims to remove unwanted fluctuations from an image sequence. This paper proposes a novel stabilization system making use of a fuzzy filter constructed by dynamic system based estimator definition with a fuzzy corrector. The stabilization system selectively switches between a pre-defined set of membership functions so as to improve gross movement tracking and stabilization performance. The stabilization results of the proposed system are compared with results of the Super SteadyShot stabilization system incorporated into SONY® camcorders.
    Leto Hall : Networks and Security II
      Access Network Mobility Management. Sang-Hwan Jung, Do-Hyeon Kim, You-Ze Cho1
        Recently, many micro-mobility-supporting protocols have been suggested, such as the regional registration protocol and Cellular IP. In these protocols, mobility is mainly managed by the mobile node itself when it moves within an access node. However, these protocols often have a long registration delay based on variations in the advertisement message broadcasting period and location management message transmission period. Furthermore, various problems, including radio resource wastage and an increased network load, can also occur with these protocols. Accordingly, the current paper proposes the ANMM (Access Network Mobility Management) protocol as an improved and efficient protocol for supporting micro-mobility in an access network. To realize the ANMM protocol, an effective adaptation method is proposed for link-layer handoff information along with a tunneling scheme between an access node and the gateway in an access network. As such, the ANMM protocol is able to minimize the registration delay, signaling overhead, and radio resource wastage.
      Application of Fiat-Shamir Identification Protocol to Design of a Secure Mobile Agent System. Seongyeol Kim, Ilyong Chung
        Even though an agent system contributes largely to mobile computing on distributed network environment, it has a number of significant security problems. In this paper, we analyze security attacks to this system presented by NIST[3]. In order to protect it from them, we suggest a security protocol for a mobile agent system by employing Identity-based key distribution and digital multi-signature scheme. To solve the problems described on NIST, securities of mobile agent and agent platform should be accomplished. Comparing with other protocols, our protocol performs both of these securities, while other protocols mention only one of them. Also, it is designed to guarantee the liveness of agent, and to detect message modification immediately by verifying the execution of agent correctly.
      Design and Implementation of a Secure Group Communication Protocol on a Fault Tolerant Ring. Özgür Saglam, Mehmet E. Dalkiliç, Kayhan Erciyes
        We describe a secure group communication protocol for a fault-tolerant synchronous ring. Our protocol, named SSRP (Secure Synchronous Ring Protocol), integrates a secure group communication facility into an existing scalable, fault-tolerant ring protocol. SSRP is a hierarchical group communication protocol that employs Cliques GDH [4] contributory key man-agement protocol and Diffie-Hellman encryption algorithm. Security related functions and group communication functions are integrated in a single layer guaranteeing that not only the application messages of the group, but also the messages related to the group communication layer are protected. A novel fault-tolerant leader selection algorithm and a proof of Virtual Synchrony semantics on SSRP are also given.
      Covert Channel Detection in the ICMP payload using Support Vector Machine. Tae-Shik Sohn, Jong-Sub Moon
        Nowadays, threats of information security become a big issue in internet environments. Various security solutions are used as such problems' countermeasure; IDS, Firewall, ESM and VPN. But, TCP/IP protocol based Internet basically have much vulnerability of protocol itself. Specially, ICMP traffic is ubiquitous to almost every TCP/IP based network. As such, many firewalls and networks consider ICMP traffic to be benign and will allow it to pass through, unmolested. But, attackers can generate arbitrary information tunneling in the data portion of ICMP packets. This channel exists because network devices do not filter the contents of ICMP traffic. So, attackers can tunnel(covert channel) any information they want. To detect a ICMP covert channel, our approach use SVM which has excellent performance in pattern classification problems. Our experiments showed that the proposed method could detect a ICMP covert channel from normal ICMP traffic using Support Vector Machine.
    Apollo Hall : Intelligent Systems and Robotics I
      Estimating Distributions in Genetic Algorithms. Onur Dikmen, H. Levent Akin, Ethem Alpaydin
        The canonical operators of genetic algorithms, i.e., mutation and crossover, have nondeterministic effects on the population.They use information from only one or two fit individuals and risk deforming the chromosomes of fit individuals and cause an interruption in the progression. Estimation of Distribution Algorithms (EDAs) use probabilistic models rather than mutation and crossover, to guide the progression of genetic algorithms by placing a density over all fit individuals and sampling from this density. EDA therefore makes better use of the fitness information of the previous generation and promise faster convergence without losing any schemata. We consider parametric, nonparametric, and semiparametric models for density estimation in the EDA template with continuous genes. We compare these methods with standard backpropagation and GA proper in the problem of training a multilayer perceptron which is a complex nonlinear estimator. Our results indicate that our algorithms perform definitely better than the proper genetic algorithm (GA) on every problem and can find better solutions than those of backpropagation in training a MLP.
      Design and Usage of a New Benchmark Problem for Genetic Programming. Emin Erkan Korkmaz, Gokturk Ucoluk
        Not so many benchmark problems have been proposed in the area of Genetic Programming (GP). In this study, a new artificial benchmark problem is designed for GP. The different parameters that can be used to tune the difficulty of the problem are analyzed. Also, the initial experimental results obtained on different instances of the problem are presented.
      The modular genetic algorithm: exploiting regularities in the problem space. Ozlem O. Garibay, Ivan I. Garibay and Annie S. Wu
        We introduce the modular genetic algorithm (MGA). The modular genetic algorithm is a search algorithm designed for a class of problems pervasive throughout nature and engineering: problems with modularity and regularity in their solutions. We hypothesize that genetic search algorithms with explicit mechanisms to exploit regularity and modularity on the problem space would not only outperform conventional genetic search, but also scale better for this problem class. In this paper we present experimental evidence in support of our hypothesis. In our experiments, we compare a limited version of the modular genetic algorithm with a canonical genetic algorithm (GA) applied to the checkerboard-pattern discovery problem for search spaces of sizes 2^{32}, 2^{128}, and 2^{512}. We observe that the MGA significantly outperforms the GA for high complexities. More importantly, while the performance of the GA drops 22.50% when the complexity of the problem increases, the MGA performance drops only 11.38%. These results indicate that the MGA has a strong scalability property for problems with regularity and modularity in their solutions.
      A Realistic Success Criterion for Discourse Segmentation. Meltem Turhan Yondem, Gokturk Ucoluk
        In this study, compared to the existing one, a more realistic evaluation method for discourse segmentation is introduced. It is believed that discourse segmentation is a fuzzy task [Pas 96]. Human subjects may agree on different discourse boundaries, with high agreement among them. In the existing method a threshold value is calculated and sentences that marked by that many subjects are decided as real boundaries and other marks are not been considered. Furthermore automatically discovered boundaries, in case of being misplaced, are treated as a strict failure, disregarding the proximity wrt to the human found boundaries. The proposed method overcomes these shortcomings, and credits the fuzziness of the human subjects' decisions as well as tolerates misplacements of the automated discovery. The proposed method is tunable from crisp/harsh to fuzzy/tolerant on human decision as well as automated discovery handling.
    Artemis Hall : Software Engineering I
      Describing Web Service Architectures through Design-by-Contract. Sea Ling, Iman Poernomo and Heinz Schmidt
        Architectural description languages (ADLs) are used to specify a high-level, compositional view of a software application, specifying how a system is to be composed from coarse-grain components. ADLs usually come equipped with a formal dynamic semantics, facilitating specification and analysis of distributed and event-based systems. In this paper, we describe TrustME, an ADL for modelling architectures systems based built from web services. We describe how its syntax and semantics meets concerns specific to Business-to-business (B2B). The ADL provides a framework that provides both a process and a structural view of web service-based systems. We use Petri-net descriptions to give a dynamic view of business workflow for web service collaboration, and the ADL to provide a static, compositional, organisational view of web service deployment. We adapt the approach Schmidt to define a form of design-by-contract (see Meyer) for configuring workflow architectures. This serves as a configuration-level means of constructing safer, more robust systems.
      Modeling of Web Applications using SDL. Joe Abboud Syriani, Nashat Mansour
        The complexity of Web applications is increasing and modeling is used to manage such complexity. In this work, we propose modeling the architecture of web applications using the Specification and Description Language (SDL) that is a formal description language. SDL is shown to be quite convenient for modeling features of web application such as hyperlinks, sending and receiving data and client-server communication. Hence, it facilitates our understanding of web applications. Further, SDL modeling allows us to extend existing implementation and verification techniques to web applications.
      Representing Variability Issues in Web Applications: A Pattern Approach. Rafael Capilla, N. Yasemin Topaloglu
        Web applications have unique characteristics that require suitable software engineering practices in the development process. In this way, software architectures and pattern-based approaches are suitable design techniques for modeling purposes. But if we want to build sets of similar systems, we need to represent the common and variable aspects of such systems under an architectural point of view. Therefore, representing and managing those variable issues is a goal to achieve when designing similar software applications. In this work we will try to deal with the variability problem from a pattern point of view as well as applying this to web software products.
      Designing Reusable Web-Applications by employing Enterprise Frameworks. Marius Dragomiroiu, Robert Gyorodi and Ioan Salomie
        Given the complexity of web-applications, their development process should focus on improving reusability and flexibility of the application. An approach to meet these concerns is proposed in this paper by employing enterprise frameworks. Enterprise Frameworks encapsulate reusable, tailorable software solutions as a collection of collaborative components, assuring integration with new or existing components, reducing in this way the complexity of the systems. The paper presents a development process of enterprise frameworks for web-applications targeting to improve their flexibility and reusability. A compositional design pattern targeting to increase framework flexibility is also proposed.
19:00Welcome Cocktail

November 4, 2003
9:00Invited Talk 3
    Zeus Hall : Invited Talk III
      Web Information Resource Discovery: Past, Present, and Future. Gultekin Ozsoyoglu
10:00Coffee Break
10:30Session 3
    Zeus Hall : Multimedia I
      Improved POCS-Based De-blocking algorithm for Block-Transform Compressed Images. Yoon Kim, Chun-Su Park, Kyunghun Jang, and Sung-Jea Ko
        This paper presents a postprocessing technique based on the theory of projections onto convex sets (POCS) to reduce the blocking artifacts in low bit rate BDCT-coded images. In the block discrete cosine transform (BDCT), the image is divided into a grid of non-overlapped 8 X 8 blocks, and then each block is coded separately. Thus, a block, which is shifted one pixel diagonally from the original grid of BDCT, will include the boundary of the original 8 X 8 block. If blocking artifacts are introduced along the block boundary, the frequency characteristics of this shifted block will be different from those of the original block. Therefore, a comparison of frequency characteristics of these two overlapping blocks can detect the undesired high-frequency components, mainly caused by the blocking artifacts. By eliminating these undesired high-frequency components adaptively considering the local statistical properties of the image, robust smoothing projection operator can be obtained. Computer simulation results indicate that the proposed scheme provides better visual performance than conventional postprocessing algorithms.
      POCS-Based Enhancement of De-interlaced Video. Kang-Sun Choi, Jun-Ki Cho, Min-Cheol Hwang, Sung-Jea Ko
        To convert an interlaced video into a progressive one effectively, de-interlacing techniques have been developed. However, existing de-interlacing techniques can not perfectly remove high frequency alias components inherently existing in the interlaced video. In this paper, based on the theory of POCS, we propose a video enhancement technique to improve the visual quality of de-interlaced video. We introduce novel constraint sets that are suitable for the characteristics of de-interlaced video and derive the projection operators for those sets. These projection operators using multiframes can reduce high frequency alias components of the de-interlaced video effectively. Extensive computer simulations show that the proposed method significantly improve the quality of the de-interlaced video by restoring the meaningful frequency information of the original progressive video.
      Effect of the generation of MPEG-frames within a GOP on queueing. J.C. Lopez-Ardao, M. Fernandez-Veiga, R.F. Rodriguez-Rubio, C. Lopez-Garcia, A. Suarez-Gonzalez, D. Teijeiro-Ruiz
        MPEG video traffic is expected to represent most of the load in the future high-speed networks. Adequate traffic models for MPEG Variable Bit-Rate (VBR) video are important for network design, performance evaluation, admission control and resource allocation. It is well-known that VBR video exhibits long-range correlations over arbitrarily long time-scales, a phenomenon usually referred to as Long-Range Dependence(LRD). Many models for VBR video traffic have been proposed in the literature. However, while the correlation between Groups of Pictures (GOPs) has been widely analyzed in literature, little effort has been devoted up to now to the generation of the different frame-types within a MPEG GOP. Due to the difficulty and complexity involved in this issue, this is often neglected even though it is a fundamental characteristic of MPEG traffic and it might have an important impact on queueing performance. In fact, many works avoid to descend to the frame level proposing models for the GOP process. In this paper, we analyze the impact on queueing performance of different solutions proposed in the literature for generating the different types of MPEG frames within a GOP (these solutions have never been compared and analyzed jointly). In this way, we can be in a good position to use the best model for MPEG in terms of simplicity, computational efficiency and queueing performance, depending on the performance metric to study (loss rate, mean delay and jitter).
      A Solution to the Composition Problem in Object-based Video Coding. Jeong-Woo Lee and Yo-Sung Ho
        In this paper, we introduce the composition problem associated with object-based video coding and propose a solution to this problem. Although the object-based rate control algorithm can provide the overall coding gain, it may create the composition problem due to different temporal resolutions in object encoding. By checking shape changes of video objects, we can minimize the possibility of the composition problem at the encoder. At the decoder, we can also apply hole detection and recovery algorithms to eliminate the effect of the composition problem to the human visual system.
    Leto Hall : Networks and Security III
      POLICE: A Novel Policy Framework. Taner Dursun, Bülent Örencik
        In this paper we present a complete policy-based framework, composed of a policy specification language and its deployment and management models for policy distribution. The Police policy language provides a common means of specifying every kind of policies that may be involved in management of distributed systems. It supports obligations and permissions. The Police policies contain event triggered action sets for policy-based management of distributed systems. Other key concepts of the framework include domains used to group objects, and distributed conflict handling.
      On the Evaluation of Availability in Computer Networks Based on an N-Tier Client/Server Architecture. F. Coelho, J. Sauvé, C. Barenco, J. García
        Published work on computer network dependability frequently uses availability as a performance measure. However, although several ways of defining availability have been proposed, none capture the overall level of service obtained by the client hosts in a modern n-tier client/server architecture. We propose such a measure by calculating the fraction of client hosts receiving complete services from the network. We also extend a published, efficient heuristic method for calculating availability to take into account our new proposed measure. The end result is a procedure of polynomial complexity O(nt4) where nt is the total number of components (hosts, links and inteconnection equipment) in the network. Numerical results of applying the method to several networks are given.
      Distributed Multicast Routing For Efficient Group Key Management. John C Felix, S Valli
        Multicast is an evolving technology for efficient transmission for one-to-many and many-to-many communications. The successful deployment of secure multicast model needs to be more distributed rather than the current centralized approach. In this work, a distributed approach in multicast routing is proposed which enhances the group key management schemes over a large-scale network. Existing work prove that group key management is very much vulnerable due to latency and complexity involved in multicast transmission. This model is designed to reduce latency and distribute the complexity. The assumptions based on which this work was implemented are discussed.
    Apollo Hall : Intelligent Systems and Robotics II
      Implementing Agent Communication for a Multiagent Simulation Infrastructure on HLA. Erek Gokturk, Faruk Polat
        Multiagent simulation is gaining popularity due to its intuitiveness and ability in coping with domain complexity. HLA, being a distributed simulation architecture standard, is a good candidate for implementing a multiagent simulation infrastructure on, provided that agent communication can be implemented. In this paper, we present a layered approach to the agent communication, followed by a discussion of implementing the lowest two layers of this approach using HLA and the agent communication language KQML in the context of a multiagent simulation.
      The Real-Time Development and Deployment of a Cooperative Multi-UAV System. Ali Haydar Goktogan, Salah Sukkarieh, Gurce Isikyildiz,Eric Nettleton, Matthew Ridley,Jong-Hyuk Kim, Jeremy Randle and Stuart Wishart
        This paper presents a systems view of the Autonomous avigation and Sensing Experimental Research (ANSER) project. ANSER is one of the most advanced UAV projects of its kind, which is aimed at demonstrating Decentralised Data Fusion (DDF) and Simultaneous Localisation and Map (SLAM) building on multiple cooperative UAVs. The demonstration of DDF and SLAM require both navigation and terrain sensors to be carried onboard by the UAVs. These include an INS/GPS navigation system, millimeter wave (MMW) radar, and both a single vision node and a vision node augmented with a laser system. This paper presents the implementation of the algorithms, sensors and platforms, along with their interaction to address this demonstration. Furthemore, the paper will present the high fidelity real time simulator which is implemented to thoroughly test all algorithms and sensors before actual implementation in the environment.
      All Bids for One and One Does for All: Market-Driven Multi-Agent Collaboration in Robot Soccer Domain. Hatice Köse, Çetin Meriçli, Kemal Kaplan and H.Levent Akin
        This work proposes a novel approach for introducing market-driven strategy to robot soccer domain in order to solve vital issues related to multi-agent coordination. In robot soccer two groups of robots namely “teams”, compete with each other to win the match. For the benefit of the team, robots should work collaboratively, whenever possible. Market-driven approach applies the basic properties of free market economy to a team of robots, to increase the profit of team as much as possible. This approach lies on the assumption that maximizing individual profit will approximate the global profit maximization. In several works, this method was applied to some open issues in multi-agent systems like multi-robot exploration and coordination, but these implementations were limited. In this work, for the first time this approach is applied to robot soccer domain, which is one of the prominent topics of multi-agent researches, as being a complex, dynamic and real-time event. In this paper, a market-driven collaborative task allocation algorithm for robot soccer domain which differs from many other multi-agent problems with its highly dynamic and complex behavior is proposed and experimental results obtained are discussed.
      Effects of the Trajectory Planning on the Model Based Predictive Robotic Manipulator Control. Fevzullah Temurtas, Hasan Temurtas, Nejat Yumusak , Cemil Oz
        In this study, the application of the single input single output (SISO) neural generalized predictive control (NGPC) and SISO generalized predictive control (GPC) to a three joint robotic manipulator are presented. The sinusoidal and cubic trajectory principles were used for position reference and velocity reference trajectories. NGPC-SISO algorithm performs better results than GPC-SISO algorithm for both trajectories. The GPC-SISO robotic manipulator control results have better values in the case of the sinusoidal trajectory, but the NGPC-SISO robotic manipulator control results for both the cubic and sinusoidal trajectory are almost similar.
    Artemis Hall : Software Engineering II
      Multi-Agent Based Integrated Framework for Intra-Class Testing Of Object-Oriented Software. P. Dhavachelvan and G. V. Uma
        ABSTRACT The primary features of the Object-Oriented paradigm lead to develop a complex and compositional testing framework for object-oriented software. The increased size and complexity of software systems has led to the current focus on developing distributed applications that are constructed from component-based systems. A component-based system is composed of both data and functionality and is configurable through parameters at run-time. For an object-oriented application, class definitions provide the basic components of a program. Low-level component testing is nothing but the unit testing, which is to be performed on the independent units without any interface and interactions. This is referred as Autonomous Unit Level (AUL) testing and it is true for conventional system testing but not for object oriented systems, since an object (class) is to be considered as an unit. Testing a class for its functionality means testing its member. The general members of a class are data members, constructors and methods. In the object-oriented environment, generally the interaction between the methods can be classified as follows. Case-I Interaction between the methods of same class. Interaction between the methods of same class and program functions. Case-II Interaction between the methods of different classes. Interaction between the methods of different classes and program functions. In case-II, interaction between different class members can be referred as unit?to?unit interaction. Normally the unit-to-unit interaction is to be examined in the integration-testing phase. But in case-I, the program functions can’t be considered as separate units. So, the interaction between the members of a class and program functions must be examined during the unit (object) testing. This is referred as Inter-Procedure Level testing (IPL) and it is not a part of the integration testing. Considerable research has gone into the development of methods for evaluating how ‘good’ a test set is for a given program against a given specification. Such criteria are also known as ‘Test Adequacy Criteria’ or simply ‘Adequacy Criteria’. A testing technique may use one or more of these criteria to assess the adequacy of a test set for a given unit and then decide whether to stop testing this unit or to enhance the test set by constructing additional test cases needed to satisfy a criterion. In principle, such criteria and the procedures may also be applied for the assessment of tests for subsystems. Agent technologies facilitate software testing by virtue of their high-level abstraction for interactions. In this paper, we propose a Multi-Agent based approach to enhance the definition for class testing in object-oriented paradigm. The Integrated framework has been built on two testing techniques namely Mutation Testing and Capability Testing. In both the cases, testing is carried out at AUL and IPL. This model provides a variety of adequacy criteria by developing separate agents and defining their responsibilities in an efficient way. This development is motivated by the need to assess test sets for subsystems, in which come about due to the complications during the unit testing. This proposed intra?class testing results in higher degree of control over integration testing costs on object-oriented software.
      Test Case Generation According to the Binary Search Strategy. Sami Beydeda, Volker Gruhn
        One of the important tasks during software testing is the generation of appropriate test cases. Various approaches have been proposed to automate this task. The approaches available, however, often have problems limiting their use. A problem of dynamic test case generation approaches, for instance, is that a large number of iterations can be necessary to obtain test cases. This article proposes a novel algorithm called binary search-based test case generation (BINTEST) algorithm. Binary search conducts searching tasks in logarithmic time, as long as its assumptions are fulfilled. This article shows that these assumptions can also be fulfilled in the case of path-oriented test case generation and presents an algorithm which can be used to generate test cases covering certain paths in control flow graphs in methods.
      Software Quality Improvement Model for Small Organizations. Rabih Zeineddine, Nashat Mansour
        Software quality improvement process remains incomplete if it is not initiated and conducted through a wide improvement program that considers process quality improvement, product quality improvement, and evolution of human resources. But, small software organizations are not capable of bearing the cost of establishing software process improvement programs. In this work, we propose a new software quality improvement model for small organizations, SQIMSO, based on three major issues. The first issue is that every improvement program should be wide enough to include the three main trends. The second issue is that any process quality model should answer the question 'How to do' things. The third issue is that any suggested quality model should be practical enough to be implemented by small software organizations for saving cost and time without decreasing the quality level. SQIMSO also draws upon international quality standards, models, experiences, and on a local field survey.
      Modeling and Analysis of Service Interactions in Service-oriented Software. WooJIn Lee
        As the Internet usage increases rapidly, an earnest desire for flexible software applications grows larger for reflecting diverse users¡¯ demands, for handling evolution of software applications, and for treating pressure of short-term development cycle. In this trend of flexible software, service-oriented software concept is introduced, in which a system is considered as a set of flexible or distributed services. In service-oriented software approach, it is necessary to provide an analysis environment for abnormal service interactions as well as to provide a service execution framework. In this paper, we provide an approach for modeling and analyzing service interactions by using Petri nets. Each service is described as an independent module by using a new modular Petri nets and interactions among services are also described and analyzed. As a case study, feature interactions in the telecommunication literature are discussed as an example of service-oriented software approach.
12:00Lunch
13:30Invited Talk 4
    Zeus Hall : Invited Talk IV
      Smoothed Analysis. Shanghua Teng
14:30Coffee Break
15:00Session 4
    Zeus Hall : Graphics & Computer Vision III
      Multi-Resolution Modeling in Collaborative Design. JungHyun Han, Taeseong Kim, Christopher D. Cera, William C. Regli
        This paper provides a framework for information assurance within collaborative design, based on a technique we call role-based viewing. Such role-based viewing is achieved through integration of multi-resolution geometry and security models. 3D models are geometrically partitioned, and the partitioning is used to create multi-resolution mesh hierarchies. Extracting an appropriately simplified model suitable for access rights for individual designers within a collaborative design environment is driven by an elaborate access control mechanism.
      Image-Space-Parallel Direct Volume Rendering on a Cluster of PCs. Berkant Barla Cambazoglu and Cevdet Aykanat
        An image-space-parallel, ray-casting-based direct volume rendering algorithm is developed for rendering of unstructured data grids on distributed-memory parallel architectures. For efficiency in screen workload calculations, a graph-partitioning-based tetrahedral cell clustering technique is used. The main contribution of the work is at the proposed model, which formulates screen partitioning problem as a hypergraph partitioning problem. It is experimentally verified on a PC cluster that, compared to the previously suggested jagged partitioning approach, the proposed approach results in both better load balancing in local rendering and less communication overhead in data migration phases.
      Generalization and Localization Based Style Imitation for Grayscale Images. Fatih Nar, Atilim Çetin
        An example based rendering (EBR) method based on generalization and localization that uses artificial neural networks (ANN) and k-Nearest Neighbor (k-NN) is proposed. The method involves learning phase and application phase, which means that once a transformation filter is learned, it can be applied to any other image. In learning phase, error back-propagation learning algorithm is used to learn general transformation filter using unfiltered source image and filtered output image. ANNs are usually unable to learn filtergenerated textures and brush strokes hence these localized features are stored in a feature instance table for using with k-NN during application phase. In application phase, for any given grayscale image, first ANN is applied then k-NN search is used to retrieve local features from feature instances considering texture continuity to produce desired image. Proposed method is applied up to 40 image filters that are collection of computer-generated and human-generated effects/styles. Good results are obtained when image is composed of localized texture/style features that are only dependent to intensity values of pixel itself and its neighbors.
      Comparison of Feture Sets using Multimedia Translation. Pinar Duygulu, Ozge Can Ozcanli, Norman Papernick
        Feature selection is very important for many computer vision applications. However, it is hard to find a good measure for the comparison. In this study, feature sets are compared using the translation model of object recognition which is motivated by the availablity of large annotated data sets. Image regions are linked to words using a model which is inspired from the machine translation. The word prediction performance is used to evaluate large number of images.
    Leto Hall : Spec.Ses. - Data Security and Digital Watermarking
      Practical Security Improvement of PKCS#5. Sanghoon Song, Taekyoung Kwon, and Ki Song Yoon
        A public key infrastructure (PKI) is being deployed in a field of network security. PKCS#5 is one of the most popular standards in PKI framework, intended for the practical implementation of password-based cryptography. So, the PKCS#5 encryption must be useful for general software applications within multimedia systems. However, it has a critical weak point in terms of security such as being vulnerable to off-line attacks due to the password-derived encryption key. In this paper, we provide a practical and simple method to improve security of the PKCS#5 encryption without modifying the installed base. The idea is to hide a salt by exploiting several existing schemes.
      Wavelet Packet Based Digital Watermarking for Remote Sensing Image Compression. Su-Young Han and Seong-Yun Cho
        In this paper, a new watermark algorithm that based on wavelet packet transform is proposed for watermark of the remote sensing images, which include many high frequency components. The proposed watermark algorithm is used in the high frequency component of image and applies watermark to the overall subband that include the lowest frequency band. And the watermark is embedded on original image after selecting the significant wavelet packet coefficient. For selecting significant coefficients that apply watermark, zerotree is applied to packet transform using CPSO (Coefficient Partitioning Scanning Order) for imperceptibly and robustness. From the experimental result, the proposed algorithm shows better invisibility and robustness performance compare with conventional watermark methods. Especially, it demonstrates better robustness for high image compression in the remote sensing images application.
      A Video Watermarking Algorithm based on the Human Visual System Properties. Ji-Young Moon, Yo-Sung Ho
        In this paper, we propose a new video watermarking algorithm based on the human visual system (HVS) properties to find effective locations in video sequences for robust and imperceptible watermarks. In particular, we define a new HVS-optimized global masking map for hiding watermark signals by combining frequency, spatial, and motion masking effects of HVS. In this paper, we generate the watermark by the bit-wise exclusive-OR operation of a logo image and a random sequence, and we embed the watermark in the uncompressed video sequence. The amount of inserted watermarks is controlled by the peak-signal-to-noise ratio of the watermarked frame. Experimental results show that the proposed method is imperceptible and robust against various attacks with a good watermark capacity.
      Multiple Description Image Coding for Image Data Hiding in the Spatial Domain. Mohsen Ashourian and Yo-Sung Ho
        In this paper, we develop a robust image data hiding scheme based on multiple description coding of the signature image. At the transmitter, the signature image is encoded by balanced two-description scalar quantizers in the wavelet transform domain. The information of the two descriptions are embedded in the host image in the spatial domain with a masking factor derived from the gradient of the image intensity values. At the receiver, the multiple description decoder combines the information of each description and reconstructs the original signature image. We experiment the proposed scheme for embedding a gray-scale signature image of 128×128 pixels size in the spatial domain of a gray-scale host image of 512×512 pixels. Results show that data embedding based on multiple description coding has low visible distortions in the host image and robustness to various signal processing and geometrical attacks, such as addition of noise, quantization, cropping and down-sampling.
    Apollo Hall : Database and Information Retrieval II
      RUBDES : A Rule Based Distributed Event System. Ozgur Koray Sahingoz, Nadia Erdogan
        In the last years the event-based communication paradigm has been largely studied and considered as a promising approach to develop the commu-nication infrastructure of distributed systems. It is particularly interesting when easy reconfiguration and decoupling among components is required. In fact, it allows events to be propagated in a way that is completely hidden to the com-ponent that has generated them as well as to the receivers. RUBDES (Rule Based Distributed Event System) is a distributed event system that allows the use of composite events in publish/subscribe computational model. In this sys-tem, an event is represented as an object and a rule is represented as an expres-sion or a function that is evaluated or executed depending on the occurrence of events. This paper presents the design details of RUBDES and usage of Rule Definition Language (RDL) to describe composite events and event filters
      Virtual Interval Caching Scheme for Interactive Multimedia Streaming Workload. Yeonseung Ryu
        In this paper, we present a novel buffer management algorithm for interactive multimedia streaming workload. We carefully examine the workload traces obtained from several streaming servers in service. The analysis results show that most users exhibit non-sequential access pattern using VCR-like operations such as jump backward and jump forward. Moreover, short jump accesses are shown to be common. We exploit the workload characteristics of the VCR-like operation and develop a buffer caching algorithm called Virtual Interval Caching scheme. Experimental results show that the proposed buffer management scheme yields better performance than the legacy schemes.
    Artemis Hall : Architectures and Systems II
      Courses Modeling in E-Learning Context. V. Carchiolo, A. Longheu, M. Malgeri, G. Mangioni
        The computer-based sharing and dissemination of knowledge and learning activities are known as 'E-learning'. In this paper we propose an E-learning model, focusing in particular on courses modeling, which aims at promoting the sharing and reuse of courses contents and teaching materials, allowing the construction of personalized learning paths.
      An e-tutoring service architecture based on overlay networks. N. Minogiannis, Dr. Ch. Patrikakis, A. Rompotis, F. Ninos
        In this paper, a comprehensive e-tutoring service framework is presented. It comprises of a set of individual applications implemented based on the use of existing open source tools. The significant point here is the flexibility of the implementation proposed, that allows it to use a combination of unicast and multicast without posing any requirements for the supporting network infrastructure. This is achieved through the use of an overlay network architecture that allows for dynamic configuration of the media transmission and relay points.
      Some Intrinsic Properties of Interacting Deterministic Finite Automata. Hürevren KILIÇ
        The agent controllability of the environment is investigated using simple deterministic interacting automata pair model. For this purpose, a general extended design approach for such couple is developed. In the experiments, we focused on simple binary state case and generated stability/cycle behavior characteristics map for the couple. Examinations on the map showed that the behavior of the couple shows some initial value sensitivity. Also, we observed some non-controllable agent/environment couple definition which may imply an inherent communication border between agent and the environment.
      Temporal Modelling in Flexible Workflows. Panagiotis Chountas, Ilias Petrounias, Vassilis Kodogiannis
        The need for explicit time representation in workflow environments has been recently identified. Although the concept of time is an intrinsic part of a workflow application, time management has been treated as an issue of ordering the constructs of the workflow specification. This traditional approach aids mainly in the monitoring of activity deadlines. There is limited support for modelling and representation of time constraints associated with the processes and their activities or cases. This paper presents a temporal formalism for representing workflow specifications. We further argue that integrating workflows with temporal databases can further enhance the workflow specification. We propose a way for encoding the history of processes as well as the history of activities and their cases-items with respect to the time dimension and temporal uncertainty. Overall this paper is proposing a framework for modelling time and temporal uncertainty as an intrinsic part of the process dimension or control flow dimension.
16:30Session 5
    Zeus Hall : Computer Science Theory
      Approximation Algorithms for Degree-constrained Bipartite Network Flow. Elif Akcali and Alper Üngör
        We consider a tool- and setup-constrained short-term capacity allocation problem that arises in operational level planning at a semiconductor wafer fabrication facility.We formulate this problem as a degree-constrained network flow problem on a bipartite graph. We show that the problem is NP-hard and propose the first constant factor (1/2) approximation algorithms. Experimental study demonstrates that, in practice, our algorithms give solutions that are on the average less than 1.5% away from the optimal solution in less than a second.
      Demonic I/O of compound diagrams monotype/residual style. Fairouz Tchier
        We show how the notion of relational diagram, introduced by Schmidt, can be used to give a single demonic de nition for a wide range of programming constructs. Our main result is Theorem 11, where we show that the input-output( I/O) relation of a compound diagram is equal to that of the diagram in which each sub-diagram has been replaced by its input-output relation. This process is repeated until we obtain elementary diagrams to which we apply the results given in previous work.This is achieved by using monotypes and residuals.
      Fuzzy Logic and Neural Network Applications on the Gas Sensor Data: Concentration Estimation. Fevzullah Temurtas, Cihat Tasaltin, Hasan Temurtas, Nejat Yumusak, Zafer Ziya Ozturk
        In this study, a fuzzy logic based algorithm is presented for the concentration estimation of the CCl4 and CHCl3 gases by using the steady state sensor response and an artificial neural network (ANN) structure is proposed for the concentration estimation of the same gases inside the sensor response time by using the transient sensor response. The Quartz Crystal Microbalance (QCM) type sensors were used as gas sensors. A computer controlled measurement and automation system with IEEE 488 card was used to control of the gas concentration values and to collect the sensor responses. Acceptable performance was obtained for the concentration estimation with fuzzy inference. And the appropriateness of the artificial neural network for the gas concentration determination inside the sensor response time is observed.
      A Security Embedded Text Compression Algorithm. Ebru Celikel, Mehmet Emin Dalkilic
        Abstract. Although conventional compression tools achieve good compression rates, they ignore the security issue. This study presents the design and implementation of a lossless compression algorithm with embedded security to fill that gap. The scheme introduced is a system with encoding and decoding and is oriented for text type of data. It is implemented on sample text files from stan-dard English Calgary Corpus. Two ideas, one hiding the encryption key by using a PRNG and the other employing multiple iterations to dissipate language statistics, are suggested to strengthen the security of the system. Both ideas are implemented and promising results are obtained.
      An Alternative Compressed Storage Format for Sparse Matrices. Anand Ekambaram and Euripides Montagne
        The handling of the sparse matrix vector product(SMVP) is a common kernel in many scientific applications. This kernel is an irregular problem, which has led to the development of several compressed storage formats such as CRS, CCS, and JDS among others. We propose an alternative storage format, the Transpose Jagged Diagonal Storage(TJDS), which is inspired from the Jagged Diagonal Storage format and makes no assumptions about the sparsity pattern of the matrix. We present a selection of sparse matrices and compare the storage requirements needed using JDS and TJDS formats, and we show that the TDJS format needs less storage space than the JDS format because the permutation array is not required. Another advantage of the proposed format is that although TJDS also suffers the drawback of indirect addressing, it does not need the permutation step after the computation of the SMVP.
    Leto Hall : Parallel and Distributed Computing
      PES: A system for parallelized fitness evaluation of evolutionary methods. Onur Soysal, Erkin Bahceci, Erol Sahin
        The paper reports the development of a software platform, named PES (Parallelized Evolution System), that parallelizes the fitness evaluations of evolutionary methods over multiple computers connected via a network. The platform creates an infrastructure that allows the dispatching of fitness evaluations onto a group of computers, running both Windows and Linux operating systems, parallelizing the evolutionary process. PES is based on the PVM (Parallel Virtual Machine) library and consists of two components; (1) a server component, named PES-Server, that executes the basic evolutionary method, the management of the communication with the client computers, and (2) a client component, named PES-Client, that executes programs to evaluate a single individual and return the fitness back to the server. Performance of PES is tested for the problem of evolving behviors for a swarm of mobile robots simulated as physics-based models, and the speed-up characteristics are analyzed.
      Design and Evaluation of a Cache Coherence Adapter for the SMP Nodes Interconnected via Xcent-Net. Sangman Moh, Jae-Hong Shim, Yang-Dong Lee, Jeong-A Lee, and Beom-Joon Cho
        This paper presents the design and evaluation of a cache coherence adapter for the cache-coherent non-uniform memory access multiprocessor system in which symmetric multiprocessor (SMP) nodes are interconnected via Xcent-Net. The SMP node is a 4-way symmetric multiprocessor subsystem based on the Intel Xeon processors, and Xcent-Net is a dual, adaptive-routed, virtual cut-through multistage interconnection network composed of hierarchical crossbar routers. The cache coherence adapter contains a directory and a remote access cache to support the directory-based cache coherence protocol customized for the SMP nodes on Xcent-Net. For any cache design, cache size and cache line size are crucial design parameters in terms of performance and implementation, and thus they are extensively evaluated. According to the simulation results, it is shown that a 128-Mbyte remote access cache with 64-byte lines is the best choice, where the average data access latency is 9.4 ms and the effective bandwidth is 6.8 Mbytes/s per node.
      Low Cost Coherence Protocol for DSM Systems with Processor Consistency. J.Brzezinski and M.Szychowiak
        Modern Distributed Shared Memory (DSM) systems offer high speed application processing by allowing to use relaxed consistency models, such as processor consistency. Unfortunately, most of the existing coherence protocols implementing relaxed consistency in multiprocessors or loosely couples clusters use write-update strategy which incurs large communication overhead, and therefore is impractical for most distributed applications. This paper presents a new home-based coherence protocol for DSM systems with processor consistency. The protocol uses local invalidation paradigm introducing little overhead. No additional invalidation messages are required; all coherence information is piggybacked to update messages.
      Minimizing Communication Cost in Fine-Grain Partitioning of Sparse Matrices. Bora Ucar and Cevdet Aykanat
        We show a two-phase approach to address the minimization of different communication-cost metrics in fine-grain partitioning of sparse matrices for parallel processing. In the first phase, we obtain a partitioning with existing tools on the matrix to determine computational loads of the processor. In the second phase, we try to minimize communication-cost metrics. For this purpose, we develop communication-hypergraph and partitioning models. We experimentally evaluate the contributions on a PC cluster.
      Scalability and Robustness of Pull-based Anti-entropy Distribution Model. Öznur Özkasap
        There are several alternative mechanisms for disseminating information among a group of participants in a distributed environment. An efficient model is to use epidemic algorithms that involve pair-wise propagation of information. These algorithms are based on the theory of epidemics which studies the spreading of infectious diseases through a population. Epidemic protocols are simple, scale well and robust again common failures, and provide eventual consistency as well. They have been mainly utilized in a large set of applications for resolving inconsistencies in distributed database updates, failure detection, reliable multicasting, network news distribution, scalable system management, and resource discovery. A popular distribution model based on the theory of epidem-ics is the anti-entropy. In this study, we focus on pull-based anti-entropy model used for multicast reliability as a case study, demonstrate its scalability and robustness, and give our comparative simulation results discussing the performance of the approach on a range of typical scenarios.
      Concurrent Scheduling and Real-time Staging in Oversubscribed Networks. Mohammed Eltayeb, Atakan Dogan, and Fusun Ozguner
        The static staging heuristics proposed so far for data staging adhere to a method by which only one data item is processed at each communication step. Concurrent scheduling, on the other hand, allows a communication step to include more than one transfer simultaneously. This is possible because some requests are achievable through separate paths, which will yield a better performance. In this study, we propose the Extended Partial Path (EPP) heuristic as a way to work in conjunction with the concurrent scheduling. Our simulation results show that the EPP performs considerably better than a static staging heuristic in the literature.
    Apollo Hall : Intelligent Systems and Robotics III
      Nonlinear Filtering Design using Dynamic Neural Networks with Fast Training. Yasar Becerikli
        This paper presents nonlinear filtering using dynamic neural networks (DNNs). In addition, the general usage of linear filtering structure is given. DNN which has a quasi-linear structure has been effectively used as a filter with fast training algorithm such as Levenberg-Marquardt method. The test results are shown that the performance of DNN as linear and nonlinear filters is satisfactory.
      A New Approach Based on Recurrent Neural Networks for System Identification. Adem Kalinli, Seref Sagiroglu
        This paper introduces a new approach based on artificial neural networks (ANNs) to identify a number of linear dynamic systems with single recurrent neural model. The structure of single neural model is capable of dealing with systems up to a given maximum number. Single recurrent neural model is trained by the backpropagation with momentum. Total nine systems from first to third orders have been used to validate the approach presented in this work. The results have shown that the recurrent single neural model is very successful in identifying a number of systems. The new approach presented in this work provides simplicity, accuracy and compactness.
      Financial Time Series Prediction Using Mixture of Experts. M.Serdar Yümlü, Fikret S. Gürgen, Nesrin Okay
        This paper investigates the use of artificial neural networks (ANN) in risk estimation of asset returns. Istanbul Stock Exchange (ISE) index (XU100) is studied with a mixture of experts ANN architecture using daily data over a 12-year period. Results are compared to feed-forward neural networks, multilayer perceptron (MLP) and radial basis function (RBF) networks and recurrent neural networks(RNN). They are also compared to widely accepted Exponential Generalized Autoregressive Conditional Heteroskedasticity EGARCH) volatility model. These results suggest that mixture of experts (MoE) have the strength to capture the volatility in index return series and prepares a valuable basis for financial decision making.
      Prediction of Protein Subcellular Localization based on Primary Sequence Data. Mert Ozarar, Volkan Atalay, Rengul Cetin Atalay
        Eukaryotic cells are subdivided into functionally separate membrane enclosed compartments. Each compartment and its vicinity contain functionally linked proteins related to the activity of that cell compartment. In an eukaryotic cell, each protein is targeted to its specific cell localization where it exerts full function. Large scale genome analysis provides high number of putative genes to be characterized. Therefore, prediction of the subcellular localization of a newly identified protein is invaluable for determination of its function. For the prediction of subcellular localization, we have developed a method, Prediction to Subcellular Localization (P2SL), using the amino acid composition and order. The composition represents the global features in the full or partial sequences while the other represents the local features, e.g. motifs of different window sizes. This method can be used to predict the signal peptides(SP), the mitochondrial targeting peptides(mTP), the nuclear and the cytosolic sequences. For classification purposes, other than the well known traditional techniques, self-organizing maps and probabilistic approaches like k-nearest neighbours are used. The experiments are made with different parameters. P2SL is the first method which uses human genes only and has a full success rate on redundancy-reduced data sets. It will be available on the web-server http://cgh.ceng.metu.edu.tr/P2SL
      Fuzzy Variance Analysis Model. Mahdi Jalili-Kharaajoo
        In this paper, a fuzzy variance analysis model with interaction between explanatory variables using Tanaka's model is investigated. A linear programming model is formulated for measuring the value of response factors, based on Tanaka's model. The proposed model measures both values of response factors, as well as their interactions.
      Robot Mimicking: A Visual Approach for Human Machine Interaction. Algan Uskarcı, A. Aydın Alatan, M. Serdar Dindaroğlu, Aydın Ersak
        The proposed method is the preliminary step for a human-machine interaction system, in which a robot arm mimics the movements of a human arm, visualized through a camera set-up. In order to achieve this goal, the posture of a model joint, which simulates a human arm, is determined by finding the bending and yaw angles from captured images. The image analysis steps consist of preprocessing of noise via median filtering, thresholding and connected component analysis. The relation between the relative positions of these markers can be used to determine the unknown bending and yaw angles of the model joint. This information is further passed to a PUMA 760 robot arm to finalize the goal. The preliminary simulation results are promising to present that the proposed system can be utilized in a real environment in which a human (arm) can be mimicked by a machine with visual sensor.
    Artemis Hall : Spec.Ses. - Flexible Querying & Mining
      Ranking the Possible Alternatives in Flexible Querying: An Extended Possibilistic Approach. Guy de Tré, Tom Matthé, Koen Tourné and Bert Callens
        An important facet of flexible querying and information retrieval is the ranking of the possible alternatives in the result. Adequate ranking information simplifies decision making and helps the user in finding faster the requested information. This paper deals with the construction of ranking methods, which are based on the use of extended possibilistic truth values. Extended possibilistic truth values are a flexible means to model query satisfaction, which additionally allow to deal with cases where some of the imposed query criteria are not applicable. Three alternative ranking approaches are presented and compared with each other based on their applicability in flexible database querying.
      Online Mining of Weighted Fuzzy Association Rules. Mehmet Kaya, Reda Alhajj
        Mining useful information and helpful knowledge from data transactions is evolving as an important research area. Current online techniques for mining association rules identify the relationship among transactions using binary values. However, transactions with quantitative values are commonly encountered in real-life applications. In this paper, we address this problem by introducing a fuzzy adjacency lattice, and then integrate the lattice structure with linguistic weights in a way to reflect the importance of items. Experiments conducted using synthetic data show the effectiveness of the proposed method for online generation of weighted fuzzy association rules.
      Application of data mining techniques to protein-protein interaction prediction. A. Kocatas, A. Gursoy, R. Atalay
        Protein-protein interactions are key to understanding biological processes and disease mechanisms in organisms. There is a vast amount of data on proteins waiting to be explored. In this paper, we describe application of data mining techniques, namely association rule mining and ID3 classification, to the problem of predicting protein-protein interactions. We have combined available interaction data and protein domain decomposition data to infer new interactions. Preliminary results show that our approach helps us find plausible rules to understand biological processes.
      A Multi-Relational Rule Discovery System. Mahmut Uludag, Mehmet R. Tolun, Thure Etzold
        This paper describes a rule discovery system that has been developed as part of an ongoing research project. The system allows discovery of multi-relational rules using data from relational databases. The basic assumption of the system is that objects to be analyzed are stored in a set of tables. Multi-relational rules discovered would either be used in predicting an unknown object attribute value, or they can be used to see the hidden relationship between the objects’ attribute values. The rule discovery system, developed, was designed to use data available from any possible ‘connected’ schema where tables concerned are connected by foreign keys. In order to have a reasonable performance, the ‘hypotheses search’ algorithm was implemented to allow construction of new hypotheses by refining previously constructed hypotheses, thereby avoiding the work of re-computing.
      Text Categorization with ILA. Hayri Sever, Abdulkadir Gorur, Mehmet R. Tolun
        The sudden expansion of the web and the use of the Internet has caused some research fields to regain (or even increase) its old popularity. Of them, text categorization aims at developing a classification system for assigning a number of predefined topic codes to the documents based on the knowledge accumulated in the training process. We propose a framework based on an automatic inductive classifier, called ILA, for text categorization, though this attempt is not a novel approach to the information retrieval community. Our motivation are two folds. One is that there is still much to do for efficient and effective classifiers. The second is of ILA's (Inductive Learning Algorithm) well-known ability in capturing by canonical rules the distinctive features of text categories. Our results with respect to the Reuters 21578 corpora indicate (1) the reduction of features by information gain measurement down to 20 is essentially as good as the case where one would have more features; (2) recall/precision breakeven points of our algorithm without tuning over top 10 categories are comparable to other text categorization, namely similarity based matching, naive Bayes, Bayes nets, decision trees, and linear support vector machines.
      A Statistical ¥ì-partitioning method for Clustering Data Streams. Nam Hun Park and Won Suk Lee
        A data stream is a massive unbounded sequence of data elements continuously generated at a rapid rate. Due to this reason, most algorithms for data streams sacrifice the correctness of their results for fast processing time. This paper proposes a clustering method over a data stream based on statistical ¥ì-partition. The multi-dimensional space of a data domain is divided into a set of mutually exclusive equal-size initial cells. A cell maintains the distribution statistics of data elements in its range. Based on the distribution statistics of a cell, a dense cell is dynamically split into two mutually exclusive smaller cells called intermediate cells. Eventually, the dense sub-range of an initial cell is recursively partitioned until it becomes the smallest cell called a unit cell. A cluster of a data stream is a group of adjacent dense unit cells. As the size of a unit cell is set to be smaller, the resulting set of clusters is more accurately identified. Through a series of experiments, the performance of the proposed algorithm is comparatively analyzed.
20:00Gala Dinner

November 5, 2003
9:00Invited Talk 5
    Zeus Hall : Invited Talk V
      REx Algorithm for Learning Rules and Exceptions. Ethem Alpaydin
10:00Coffee Break
10:30Session 6
    Zeus Hall : Multimedia II
      A Scalable Multicast Protocol with QoS guarantie. Abderrahim Benslimane and Omar Moussaoui
        The technological advances in communication networks and computers are largely contributed to the developments of multimedia applications such as the videoconference. These applications require an efficient management of the Quality of Service (QoS) and consist of a great number of participants. In order to support such applications, we propose a hierarchical communication architecture and a multicast protocol allowing scalability. This architecture allows to guarantee the QoS. In fact, it allows to reduce efficiently the connection number and the communication delays. We examined and compared the performance of the proposed protocol and some existing protocols with simulations in NS2 tool.
      Scheduling Mixed Traffic under Earliest-Deadline-First Algorithm. Yeonseung Ryu
        Recently, real-time packet schedulers based on Earliest Deadline First(EDF) policy have been extensively studied to support end-to-end bounded delay for real-time traffic. However, the packet scheduler could not guarantee the QoS requirements of real-time traffic since it receives a number of non-real-time traffic for the purpose of management and control. In this paper, we study a packet scheduling scheme servicing non-real-time traffic using the available time of link (i.e. slack time). Proposed scheme assigns the deadline to non-real-time packets on-line and services them under EDF policy. Since proposed scheme services the non-real-time traffic when the link bandwidth is not used, it can guarantee the schedulability of real-time flows.
      Optimal Scheduling Algorithm for Stream Based Parallel Video Processing. D Turgay Altilar, Yakup Paker
        We present a new optimal scheduling algorithm called Periodic Write-Read-Compute (PWRC) scheduling for stream based parallel video processing. Although PWRC scheduling exploits the properties of the video data, it is applicable to any type of periodic data over which a data independent application is to run. The PWRC algorithm is designed considering a bust based parallel architecture allowing point-to-point communication between the host and the workers. A client-server system software is designed for the parallel system and SPMD type of programming is used. The PWRC requires a high level atomic write-read command for data transmission. Such an indivisible command couple can be created in various ways depending on the system capabilities. We analysed the PWRC scheduling algorithm by the help of a few cost model, which comprise system and application characteristics. The analysis of the cost model provides information either to form a parallel video processing system or to predict the overall performance of an existing system. A data transfer bandwidth constraint is also defined, in order to ensure that the system running the PWRC scheduling algorithm meets real-time requirements of video processing.
      Network-Aware Video Redundancy Coding with Scene-Adaptation for H.263+ Video. Jae-Young Pyun, Jae-Hwan Jeong, Kwang-Il Ji, Kyunghun Jang, and Sung-Jea Ko
        This paper introduces a new error-resilient mechanism based on video redundancy coding (VRC) of H.263 Version 2, formerly known as H.263+. VRC is a mechanism to achieve temporal error resilience in error-prone environments. However, VRC is not suitable for the time-varying error-prone channel. The proposed network-aware VRC mechanism adaptively changes the prediction structure with multiple threads according to the channel status. Also, scene-adaptiveness is incorporated with the network-aware VRC to reduce the motion-jerkiness occurred by an abrupt scene change. Simulation results show that the proposed adaptive VRC mechanism does not only utilize network resources efficiently, but also reduce the fluctuation of the video quality.
    Leto Hall : Networks and Security IV
      Neural Network-Based Optical Network Restoration with Multiple-Classes of Traffic. Demeter Gokisik, Semih Bilgen
        Neural-network-based optical network restoration is illustrated over an example in which multiple classes of traffic are considered. Over the preplanned primary and backup capacity, optimal routing and wavelength assignment is carried out. In case of a network failure, protection routes and optimum flow values on these protection routes are extracted from a previously trained feed-forward neural network which is distributed over the optical data communications network.
      A New Role-Based Delegation Model Using Sub-Role Hierarchies. HyungHyo Lee, YoungRok Lee, BongHam Noh
        Delegation in computer systems plays an important role in relieving security officer's management efforts, especially in a large-scale, highly decentralized environment. By distributing management authorities to a number of delegatees, scalable and manageable security management functionality can be achieved. Recently, a number of researches are proposed to incorporate delegation concept into Role-Based Access Control(RBAC) model, which is becoming a promising model for enterprise environment with various organization structures. In this paper, we propose a new role-based delegation model using sub-role hierarchies supporting restricted inheritance functionality, in which security administrator can easily control permission inheritance behavior using sub-roles. Also, we describe how role-based user-to-user, role-to-role delegations are accomplished in the proposed model and analyze our delegation model against various delegation characteristics.
      Design of a Log Server for Distributed and Large-Scale Server Environments. Atilla Ozgit, Burak Dayioglu, Erhan Anuk, İnan Kanbur, Ozan Alptekin, Umut Ermiş
        Collection, storage and analysis of multiple hosts’ audit trails in a distributed manner are known as a major requirement, as well as a major challenge for enterprise-scale computing environments. To ease these tasks, and to provide a central management facility, a software-suit, named as “Log-Hunter” has been developed. Log-Hunter is a secure distributed log server system which involves log collection and consolidation in a large-scale environment having multiple hosts that keeps at least one audit trail. This architecture also eases the inspection and monitoring of the audit trails generated on multiple hosts. By consolidating all the audit trails on a centralized server, it significantly reduces the manpower requirement, and also provides secure log storage for inspection of log entries as it becomes necessary. This paper presents the functional specifications, architecture and some preliminary performance results of the Log-Hunter.
    Apollo Hall : Graphics & Computer Vision IV
      Robust skin color segmentation using a 2D plane of RGB color space. Juneho Yi, Jiyoung Park, Jongsun Kim
        This research features a new method for skin color segmentation using a 2D plane in the RGB color space. The RGB color values of the input color image do not need to be converted into HSI or YIQ color coordinates that have popularly been used for color segmentation. We have observed an important fact that skin colors in the RGB color space are approximately distributed in a linear fashion. Based on this fact, we have applied PCA (Principal Component Analysis) techniques to RGB values of skin colors from a set of training images. We detect skin regions by the lookup of skin color histogram computed based on a 2D color plane of which two axes correspond to two directions with smallest spread of skin colors. The proposed 2D color plane for color histogram lookup has an advantage over HS or IQ color planes. By using this plane, the problem of color constancy is much relieved. A learned color histogram contains most skin colors detected in the input images and at the same time, the distribution of skin colors in the plane is invariant compared to those in the HS or IQ planes. We have evaluated the performance of the proposed method by comparing with the performance of color histogram lookup methods based on HS or IQ color plane. The experimental results show that the performance of our method is robust to illumination changes.
      Texture segmentation using the mixtures of principal component analyzers. Mohamed E.M. Musa, Robert P.W. Duin, Dick de Ridder, Volkan Atalay
        In recent years, a number of mixtures of local PCA models have been proposed. Most of these models require the user to set the number of submodels (local models) in the mixture and submodels dimensionalities (i.e. number of PC's). To make the model free of parameters, we propose a greedy EM algorithm to find a suboptimal number of submodels. For a global retained variance ratio, the proposed algorithm estimates for each submodel the dimensionality that retains the given variability ratio. We test the proposed method on texture segmentation.
      Segmentation of Protein Spots in 2D Gel Electrophoresis Images with Watersheds using Hierarchical Threshold. Youngho Kim
        2D Gel Electrophoresis (2DGE) image is the most widely used method for the isolation of the objective protein by comparative analysis of the protein spot pattern in the gel plane. The process of protein analysis is the method, which compares the protein pattern that is spread in the gel plane with the contrast group and finds interesting protein spot by image analysis. Previous 2DGE image analysis is composed of gaussian fitting, and segments protein spots by watersheds, a morphological segmentation. Watersheds have a benefit that is fast in global threshold, but induces under-segmentation and over-segmentation of spot area when gray level is continuous. The drawback was somewhat solved by marker point institution, but needs the split and merge process. This paper introduces a novel segmentation of protein spots by watersheds using hierarchical threshold, which can resolve the problem of marker-driven watersheds.
      A Turkish Handprint Character Recognition System. Abdulkerim Çapar, Kadim Taşdemir, Özlem Kılıç, Muhittin Gökmen
        This paper presents a study for recognizing isolated Turkish handwritten uppercase letters. In the study, first of all, a Turkish Handprint Character Database has been created from the students in Istanbul Technical University (ITU). There are about 20000 uppercase and 7000 digit samples in this database. Several feature extraction and classification techniques are realized and combined to find the best recognition system for Turkish characters. Features, obtained from Karhunen-Loéve Transform, Zernike Moments, Angular Radial Transform and Geometric Features, are classified with Artificial Neural Networks, K-Nearest Neighbor, Nearest Mean, Bayes, Parzen and Size Dependent Negative Log-Likelihood methods. Geometric moments, which are suitable for Turkish characters, are formed. KLT features are fused with other features since KLT gives the best recognition rate but has no information about the shape of the character where other methods have. The fused features of KLT and ART classified by SDNLL gives the best result for Turkish characters in the experiments.
    Artemis Hall : Architectures and Systems III
      Topological and Communication Aspects of Hyper-Star Graphs. J. -S. Kim, E. Oh, H.-O. Lee, and Y. -N. Heo
        A hyper-star graph HS(m,k) has been introduced as a class of lower cost interconnection networks. Hyper-star graph has more merit than hypercube when degree X diameter is used as a cost measure. In other words, they have smaller degree and diameter than hypercubes. In this paper, we consider some of the important properties of hyper-star graphs such as symmetry, w-diameter, and fault diameter. We show that HS(2n,n) is node-symmetric. We also show that the w-diameter of HS(2n,n) is bounded by the shortest path length plus 4, and fault diameter of HS(2n,n) is bounded by its diameter plus 2. In addition, we introduce an efficient broadcasting scheme in hyper-star graphs based on a spanning tree with minimum height.
      A Simple Scheme for Local Failure Recovery of Multi-directional Multicast Trees. Vladimir Dynda
        When a node in a multicast tree fails, the tree is divided into several fragments. To achieve a fault-tolerant communication, failure recovery schemes are necessary to restore the tree. We present a simple recovery scheme for overlay multicast trees that involves only failure-neighboring nodes into the restoration and keeps the original structure of the rest of the tree. The scheme is based on virtual bypass rings providing alternative paths to eliminate the faulty node and reroute the traffic. Our scheme is scalable, independent of message source and traffic direction in the tree, restores the multicast tree in real time without a significant delay penalty and our experiments show that it is efficient even un-der a heavy traffic in the tree.
      Classification of a large web page collection applying a Generalised Regression Neural Network. Ioannis Anagnostopoulos, Christos Anagnostopoulos, Vassili Loumos and Eleftherios Kayafas
        This paper proposes an information system that classifies web pages according a taxonomy, which is mainly used from seven search engines/ directories. The proposed classifier is a four-layer Generalised Regression Neural Network (GRNN) that aims to perform the information segmentation according to web page features. Many types of web pages were used in order to evaluate the robustness of the method, since no restrictions were imposed except for the language of the content, which is English. The system can be used as an assistant and consultative tool in order to help the work of human editors.
      Design and Evaluation of a Source Routed Ad hoc Network. Faysal Basci, Hakan Terzioglu, Taskin Kocak
        Effects of network parameters on the performance of mobile ad hoc networks (MANETs) have been widely investigated. However, there are certain issues related to the hardware implementation and internal parameters of the nodes present in the network that effect performance dramatically. In this work a source routed wireless network is implemented in VHDL. Basic modules in the design are mobile ad hoc nodes and a switch that emulates the wireless channel and controls the connectivity between nodes. By varying hardware parameters of the nodes under different network conditions performance of the overall system is measured and simulation results are presented.
12:00Lunch
13:30Invited Talk 6
    Zeus Hall : Invited Talk VI
      Software Process Improvement. Alec Dorling
14:30Coffee Break
15:00Session 7
    Zeus Hall : Multimedia III
      Lossy Network Performance of a Rate-Control Algorithm for Video Streaming Applications. Aylin Kantarci, Turhan Tunali
        In this paper, we present performance results of our previously developed rate control algorithm under various controlled packet loss rates. Since IP has no QoS support for real-time delivery of multimedia data, QoS control service has to be provided by the applications. Unlike traditional rate control approaches that take into account only the loss statistics, our algorithm integrated receiver buffer status into the feedback messages from the clients. Under various packet loss rates, we compared our approach to traditional two watermark approach and observed that our algorithm is more robust to varying network conditions.
      Fast Mode Decision for H.264 with Variable Motion Block Sizes. Jeyun Lee and Byeungwoo Jeon
        The new emerging video coding standard H.264 employs variable block size motion compensation using multiple references with quarter-pel motion vector accuracy. This scheme is a key feature to accomplish higher coding gain, however, also a decisive factor that increases overall computational complexity. To overcome this, we propose a novel fast mode decision scheme suited for variable block sizes by classifying coding modes based on rate-distortion cost. The experimental results show that the proposed method provides significant reduction in computational complexity without any noticeable coding loss and additional operations.
      Real-Time Advanced Contrast Enhancement Algorithm. Tae-Chan Kim
        The image quality enhancement based on digital signal processing (DSP) has been addressed as one of the crucial issues in digital display technology and market. Since real-time digital imaging should be controlled in limited speed and bits, colored motion pictures with digital display generally generate many problems such as limited operating speed of algorithm and gamut range of expressed color compared to analog cathode ray tube (CRT) display. Especially, the contrast enhancement with limited values sometimes may result in overpassing contrast limit. The changes of hue and saturation cause a damage of color nature of original image. Moreover, the abruptly changed gain during contrast enhancement causes the flickering problem as time passes. This paper introduces the image contrast enhancement algorithm named Advanced Contrast Enhancement (ACE) with adaptive and recursive method which operates at 135MHz, SXGA, keeps the color tone of original image and prevents gain from an abrupt change. The chip with ACE algorithm will be useful not only for general imaging but also for special treatment such as medical imaging to detect problems in human body pictures such as X-ray picture, ultrasound, and CT in real-time.
      A New Construction Algorithm for Symmetrical Reversible Variable-Length Codes from the Huffman Code. Wook-Hyun Jeong and Yo-Sung Ho
        Variable-length codes (VLCs) improve coding performance using statistical characteristics of source symbols; however, VLCs have disastrous effects from bit errors in noisy transmission environments. In order to overcome problems with VLCs, reversible variable-length codes (RVLCs) have been introduced as one of the error resilience tools due to their error recovering capability for corrupted video streams. Still, existing RVLCs are complicated in the design and have some rooms for improvement in coding efficiency. In this paper, we propose a new design method for a symmetrical RVLC from the optimal Huffman code table. The proposed algorithm has a simpler construction process and also demonstrates an improved performance in terms of the average codeword length than other symmetrical RVLC algorithms.
    Leto Hall : Networks and Security V
      A Simple Pipelined Scheduling for Input-Queued Switches. Sang-Ho Lee and Dong-Ryeol Shin
        Input-queued switch is useful for high bandwidth switches and routers because of lower complexity and fewer circuits than output-queued switch.However, it suffers HOL-blocking, which limits the throughput to 58%. To overcome HOL-blocking problem, many input-queued switches are controlled by sophisticated scheduling algorithms at centralized schedulers which restrict the design of the switch architecture. In this paper, we propose a simple scheduler called Pipelined and Prioritized Round Robin(PPRR) which is intrinsically distributed by each input-port. An iterative prioritized round robin scheduling algorithm in a pipelined fashion is provided. The proposed algorithm has less complexity and yet comparable performance with respect to other algorithms such as iSLIP and RPA. The effectiveness of PPRR is demonstrated with simulations under uniform and bursty traffic conditions.
      Performance Analysis of Packet Schedulers in High-Speed Serial Switches. Oleg Gusak, Neal Oliver, and Khosrow Sohraby
        In this work we examine the performance of arbitration algorithms for core high-speed serial switches (HSSS). Taking Infiniband as an example, experimental results show that, for a homogeneous network load, the average queuing delay for the switch output ports under the weighted round-robin (WRR) algorithm defined for InfiniBand is similar to the average queuing delay resulting from the largest delay-first (LDF) or first-in-first-out (FIFO) algorithms. For a 4-port switch, when the average load is high (close to 95% of the network capacity) and unbalanced with respect to the WRR weights, the difference in average delay between WRR and LDF or FIFO is large. However, for a 20-port switch and the same high unbalanced average network load, this difference is less than half of that of the 4-port switch. Further, the average queuing delay difference between WRR and LDF or FIFO diminishes quickly as the average load decreases. Hence, even for a fairly high average load, LDF or FIFO can be suggested for arbitration in core HSSS.
      A Practical Approach for Constructing a Parallel Network Simulator. Li Yue, Qian Depei and Zhang Wenjie
        Network simulation is widely used in network research to evaluate the performance of various network protocols and control algorithms. With the development of computer networks, the network models grow in size and complexity, so the execution time of simulation can be unbearably long. In this paper, we present a practical approach to construct a parallel network simulator which is based on the popular sequential network simulator ns. Parallel discrete event simulation (PDES) techniques are applied to modify the event scheduling mechanism in ns. Some necessary extensions are also made to ns network model library. Performance measures including speedup and memory consumption are evaluated at last.
      On Fair Bandwidth Sharing With RED. D. Teijeiro-Ruiz, J.C. López-Ardao, M. Fernández-Veiga, C. López-García, A. Suárez-Gonzalez, R.F. Rodríguez-Rubio, P. Argibay-Losada
        One weakness of the RED algorithm typical of routers in the current Internet is that it allows unfair bandwidth sharing when a mixture of traffic types shares a link. This unfairness is caused by the fact that, at any given time, RED imposes the same loss probability on all flows, regardless of their bandwidths. In this paper, we propose Random Rate-Control RED (RRC-RED), a modified version of RED. RRC-RED uses per-active-flow accounting to enforce on each flow a loss rate than depends on the flow's own rate. This papers shows than RRC-RED provides better protection than RED and its variants to solve that problems (like FRED, CHOKe or RED-PD), and, moreover, it is easier to implement and lighter in complexity.
    Apollo Hall : Tutorial
      Quantum Computing and Quantum Information Theory. Dan C. Marinescu
    Artemis Hall : Architectures and Systems IV
      Template-Based E-Mail Summarization for Wireless Devices. Jason J. Jung, Geun-Sik Jo
        Mobile users have been suffering from low hardware capacity, poor interface, and high communication cost of their wireless devices. In this paper, we propose the wireless e-mail framework extracting user-relevant pieces of information from each e-mail text, instead of sending full text of e-mails themselves. Not only user-defined templates but also automatically generated templates based on semantic tagging are applied to be ruleset for discriminating which parts of text should be extracted. Especially, e-mails that users are anticipating are more proper to wireless notifying application than any other information. In experiments, we verified that this system has shown the average removal of 74% redundant textual information and the maximum accurate filling of 93% template slots by collecting e-mails from DBWorld.
      Uncorrelating PageRank And In-Degrees in A Synthetic Web Model. Mieczys³aw A. K³opotek, and Marcin Sydow
        An important part of the Web research nowadays concentrates on analyzing the graph structure of WWW and its dynamics. Understanding them would have an immense impact on many branches of Information Technology and industry. It also helps in explaining some sociological phenomena observed in the Web as well as predicting the future of WWW. To achieve the above there has been constructed and tested by simulations a number of synthetic Web graph models which approximate the real Web properties with increasing accuracy.The aim of this paper is to summarize (in the synthetic manner) the most important models and measures of the Web. In addition the paper suggests some improvements to the newest models which may overcome the problem of the high correlation between PageRank and in-degree distributions. Such a correlation is present in the newest artificial Web models but not present in the real Web.
      Low Cost And Trusted Electronic Purse System Design. Mehmet Ercan Kuruoglu and Ibrahim Sogukpinar
        Electronic purse systems are more trusted than magnetic credit card payment systems. However, electronic purse technology is difficult and expensive to realize. Security is a major problem in payment systems, but off-line electronic payments have security gaps. PKI solutions, which are applicable with third parties included to the system, have some risks. Smart cards are not fully trusted. In this study, a low cost and easily applicable electronic purse system is proposed. The proposed solution is as trusted as its global world samples. Applying a simple user authentication method, memory protected smart cards is used without requiring microprocessor smart card security.
16:30Session 8
    Zeus Hall : Spec.Ses. - Ontologies and Knowledge Representation
      Ontological Cognitive Map for Sharing Knowledge between Heterogenous Businesses. Jason J. Jung, Geun-Sik Jo
        We have considered that cognitive map is one of the most efficient ways to solve the problems like the lack and uncertainty of knowledge on e-commerce. In this paper, we have designed knowledge management systems based on cognitive map and ontology and proposed the OntoCM (Ontological Cognitive Map) framework to collaboratively share knowledge between businesses by using OntoCM Repository. Thereby, we have defined OntoCM operations such as expansion, contradiction, augmentation and screener to manipulate them. Simulating synthesis patterns on OntoCM, we have extracted potential relationships between the existing concepts.
      Integration of static and active data sources. G. Nachouki & M. Quafafou
        This paper describes the design of a system, which facilitates Accessing and Interconnecting heterogeneous data sources. Data sources can be static or active: static data sources include structured or semistructured data like databases, XML and HTML documents; active data sources include services which are localised on one or several servers including Web services. The main originality of this work is to make interoperability between actives and/or static data sources based on XQuery language.
      Similarity for Conceptual Querying. Troels Andreasen, Henrik Bulskov and Rasmus Knappe
        The focus of this paper is approaches to measuring similarity for application in content-based query evaluation. Rather than only comparing at the level of words, the issue here is conceptual resemblance. The basis is a knowledge base defining major concepts of the domain and may include taxonomic and ontological domain knowledge. The challenge for support of queries in this context is an evaluation principle that on the one hand respects the formation rules for concepts in the concept language and on the other is sufficiently efficient to candidate as a realistic principle for query evaluation. We present and discuss principles where efficiency is obtained by reducing the matching problem - which basically is a matter of conceptual reasoning - to numerical similarity computation.
      Modelling Multi-Disciplinary Scientific Experiments and Information. E. C. Kaletas, H. Afsarmanesh and L. O. Hertzberger
        Emergence of advanced complex experiments in applied sciences resulted in a change in the way of experimentation. Information management plays an important role in supporting such scientific experiments. In this paper, we address the modelling requirements of scientific experiments and information. We describe a novel experiment model as the base for a support environment, and data models developed for the representation of different components of the experiment model.
      A Cooperative Paradigm for Fighting Information Overload. Daniel Gayo-Avello, Darío Álvarez-Gutiérrez, José Gayo-Avello
        The Web is mainly processed by humans. The role of the machines is just to transmit and display the contents of the documents, barely being able to do something else. Nowadays there are lots of initiatives trying to change this situation; many of them are related to fields like the Semantic Web or Web Intelligence. In this paper we describe the Cooperative Web that can be seen as a new proposal towards Web Intelligence. The Cooperative Web would allow us to extract semantics from the Web in an automatic way, without the need of ontological artifacts, with language independence and, besides of this, allowing the usage of browsing experience from individual users to serve the whole community of users.
      Global Index for Multi Channels Data Dissemination in Mobile Databases. Agustinus Borgy Waluyo, Bala Srinivasan, David Taniar
        Data broadcasting strategy is known as a scalable way to disseminate information to mobile users. However, with a very large number of broadcast items, the access time of mobile clients increase accordingly, due to high waiting time for mobile clients to find their data of interest. One possible solution is to split the database information into several broadcast channels.In this paper, we introduce global index for multi broadcast channels. A simulation model is developed to find out the performance of the technique.
    Leto Hall : E-Busines
      A Heuristic Lotting Method for Electronic Reverse Auctions. U. Kaymak, J. P. Verkade and H. A. B. te Braake
        An increasing number of commercial companies are using online reverse auctions for their sourcing activities. In reverse auctions, multiple suppliers bid for a contract from a buyer for selling goods and/or services. Usually, the buyer has to procure multiple items, which are typically divided into lots for auctioning purposes. By steering the composition of the lots, a buyer can increase the attractiveness of its lots for the suppliers, which can then make more competitive offers, leading to larger savings for the procuring party. In this paper, a clustering-based heuristic lotting method is proposed for reverse auctions. Agglomerative clustering is used for determining the items that will be put in the same lot. A suitable metric is defined, which allows the procurer to incorporate various approaches to lotting. The proposed lotting method has been tested for the procurement activities of a consumer packaged goods company. The results indicate that the proposed strategy leads to 2-3% savings, while the procurement experts confirm that the lots determined by the proposed method are acceptable given the procurement goals.
      CEVS - A Corporative E-Voting System based on EML. Dessislava Vassileva and Boyan Bontchev
        In recent years, e-voting systems become more and more important as they contribute to the overall democratic process worldwide. CEVS (Corporative E-Voting System) is a new Internet voting application developed by means of EML (Election Markup Language) technologies. The article presents an overview of the EML structure and extensions and, as well, a JAXB (Java Architecture for XML Binding) technology, both used for building the CEVS application. Next, we describe in details the CEVS software architecture and discuss aspects of its system functionality. There are given directions for elaboration of CEVS and future works according to the state-of-the-arts trends in the area.
      Smart Card Terminal Systems Using ISO-IEC 7816-3 Interface and 8051 Microprocessor Based on the System-on-Chip. Won Jay Song, Won Hee Kim, Bo Gwan Kim, Byung Ha Ahn, Munkee Choi, and Minho Kang
        A smart card terminal designed and developed to communicate with smart cards via a single System-on-Chip (SoC) is described in this paper. This proposed and developed SoC-based smart card terminal, designed with the Verilog Hardware Description Language (HDL) and the Simulation Program with Integrated Circuit Emphasis (SPICE), can be achieved and operated by proper connections to a Personal Computer (PC) and by dedicated software drivers that control the communication protocol between the smart card and the card terminal. We have also constructed an integrated test environment to verify the system developed. Through this test environment, we should be able to check all operational functions of the SoC-based developed smart card terminal microprocessor and smart card interface. The results showed that our test board operated successfully.
      A Poisson Model for User Accesses to Web Pages. Sule Gunduz, M. Tamer Ozsu
        Predicting the next request of a user as she visits Web pages has gained importance as Web-based activity increases. There are a number of different approaches to prediction. This paper concentrates on the discovery and modelling of the user's aggregate interest in a session. This approach relies on the premise that the visiting time of a page is an indicator of the user's interest in that page. Even the same person may have different desires at different times. Although the approach does not use the sequential patterns of transactions, experimental evaluation shows that the approach is quite effective in capturing a Web user's access pattern. The model has an advantage over previous proposals in terms of speed and memory usage.
      An Activity Planning and Progress Following Tool for Self-Directed Distance Learning. Nigar Sen, Nese Yalabik
        This paper presents an overview of the design and implementation of an Activity Planning and Progress Following Tool (APT) for e-learning. APT is a software based support tool designed to assist learners with their self directed distance learning (SDDL). A literature survey for the additional components of Learning Management Systems (LMS) that are needed for SDDL is conducted. As a result, the importance of “planning”, “feedback” and “resources” properties are revealed. In the continuation of the study, APT was developed by adding “Recommended Study Time Periods”, “Resources”, “Study Planning”, “User Goals” and “Progress Report” modules to the “Content Administration Tool” (CAT), which was developed before in another study. Keywords: Self-directed learning, self-directed distance learning, self-planning, progress following
      MAPSEC: Mobile-Agent Based Publish/Subscribe Platform for Electronic Commerce. Ozgur Koray Sahingoz, Nadia Erdogan
        Electronic commerce technology offers the opportunity to integrate and optimize the global production and distribution on supply chain. Com-puters of various corporations, located throughout the world, communicate with each other to determine the availability of components, to place and confirm orders, and to negotiate delivery timescales. Software agents help to automate a variety of tasks including those involved in buying and selling products over the Internet. This paper presents MAPSEC, an e-commerce system based on mobile agents, that uses publish/subscribe protocol for registration and transac-tion processing. In a large-scale and dynamic environment, there can be any number of buyers and suppliers any time. Any supplier can connect, register or unregister to the system at any time, thus preserving the dynamic structure of the system.
    Apollo Hall : Soft Computing
      Signal Compression using Growing Cell Structures: A Transformational Approach. Borahan Tümer and Betül Demiröz
        We present an adaptive compression system (ACS) that compresses signals using signal primitives obtained by the self organizing neural architecture growing cell structures (GCS). We determine the length w of the primitive that maximizes the compression. We decompose the signal into w-long segments. Then GCS is trained to adaptively construct categories from segments. A reconstruction of the original signal may be obtained as a sequence of GCS categories with some error. We analyze the performance of ACS using two criteria: CR and PRD. We define CR as the ratio of the memory space required to hold the original signal over that required by the compressed version of the signal. We define PRD as the error between original signal and reconstructed signal from the compressed signal information. CR and PRD counteract providing a trade-off among the compression potential and the reconstruction quality of ACS. We apply ACS to electrocardiogram (ECG) signals.
      A New Continuous Action-set Learning Automaton for Function Optimization. Hamid Beigy and M. R. Meybodi
        In this paper, we study an adaptive random search method based on learning automaton for solving stochastic optimization problems in which only the noise-corrupted value of objective function at any chosen point in the parameter space is available. We first introduce a new continuous action-set learning automaton (CALA) and theoretically study its convergence properties, which implies the convergence to the optimal action. Then we give an algorithm, which needs only one function evaluation in each stage, for optimizing an unknown function.
      A Selectionless Two-Society Multiple-Deme Approach for Parallel Genetic Algorithms. Adnan ACAN
        A novel multi-deme parallel genetic algorithm approach that eliminates the use of the selection operator by using multiple populations separated into two societies is introduced. Each individual population contains two subpopulations, one in each society, and individuals in one society are superior in fitness to the ones in the other and the size of subpopulations in each society is dynamically determined based on the average fitness value. The fitness-based division of individuals into two social subpopulations is based on the fact that, due to fitness-based selection procedures, most of the recombination operations take place among individuals with an above-average fitness value. Unidirectional synchronous migration of individuals is carried between populations in the same society and in the two societies. The proposed algorithm is applied for the solution of hard numerical and combinatorial optimization problems, and it outperforms the standard genetic algorithm implementation in all trials.
      Gene Level Concurrency in Genetic Algorithms. Onur Tolga Sehitoglu, Göktürk Üçoluk
        This study describes an alternative concurrency approach in genetic algorithms. Inspiring from implicit parallelism in a physical chromosome, a vertical concurrency is introduced. Proposed gene process model allows genetic algorithms work in encodings independent from the gene position ordering. This feature is used to implement a gene reordering version of genetic algorithm. Further possible models of flexible gene position encodings are discussed.
      Fuzzy Cluster Analysis of Spatio-Temporal Data. Zhijian Liu, Roy George
        The developments of new data mining tools and techniques have been necessitated by the need to analyze the vast quantities of earth science data collected. Mining this data can produce new insights into weather, climatological and environmental trends that have significance both scientifically and practically. This paper discusses the challenges posed by earth science databases and examines the use of fuzzy K-Means clustering for analyzing such data. It proposes the extension of the fuzzy K-Means clustering algorithm to account for the spatio-temporal nature of such data. The paper introduces an unsupervised fuzzy clustering algorithm, based on the fuzzy K-Means and defines a cluster validity index which is used to determine an optimal number of clusters. These techniques are validated on weather data in the South Central US. It is seen that the algorithms are able to identify and preserve regions of meteorological interest.
    Artemis Hall : Spec.Ses. - Multimedia Modeling and the Security in the Next Generation Network Information Systems
      SSE-CMM BPs to Meet the Requirements of ALC\_DVS.1 Component in CC. Sang-ho Kim, Eun-ser Lee, Choon-seong Leem, Ho-jun Shin, Tai-hoon Kim
        Security assurance requirements about the securityof development environment for IT product or system are describedin ALC_DVS (Development Security) family in the part 3 of theCommon Criteria (CC). But if the fact the site environment ITproducts or systems are being developed may meet the requirementsof ALC_DVS family is assured by performing an authorized processevaluation criteria like as the SSE-CMM and evaluator recognizethat fact, developer can reduce the burden for preparing thesite-visiting and evaluator can save the time for site-visitevaluation. In this paper we analyze the compliance betweenALC_DVS.1 of the CC and Base Practices (BPs) of the SystemsSecurity Engineering Capability Maturity Model (SSE-CMM), andreview the capability level of the SSE-CMM to meet therequirements of ALC_DVS.1
      Improved Structure Management of Gateway Firewall Systems for Effective Networks Security. Si Choon Noh, Dong Chun Lee, Kuinam J. Kim
        In this paper we propose an improved structuremanagement of gateway firewall systems. This management haveeffective network security comparing to the general structuremanagement which consist of network configurations, topologymanagement, topology and role management of bastion hosts, controlmanagement of network equipment and multiple firewalls.
      Supplement of Security-Related Parts of ISO/IEC TR 15504. Sang-ho Kim, Choon-seong Leem, Tai-hoon Kim, Jae-sung Kim
        ISO/IEC TR 15504, the Software Process ImprovementCapability Determination (SPICE), provides a framework for theassessment of software processes. This framework can be used byorganizations involved in planning, monitoring, controlling, andimproving the acquisition, supply, development, operation,evolution and support of software. But, in the ISO/IEC TR 15504,considerations for security are relatively poor to others. Forexample, the considerations for security related to softwaredevelopment and developer are lacked. In this paper we propose aprocess related to security by comparing ISO/IEC TR 15504 toISO/IEC 21827 and ISO/IEC 15408. The proposed scheme may becontributed to the improvement of security for IT product orsystem.
      New CX Searching Algorithm for Handoff Control in Wireless ATM Networks. Dong Chun Lee, Gi-sung Lee, Chiwon Kang, Joong Kyu Park
        The Crossover Switch (CX) plays an important rolein ensuring fast and seamless handoff in Wireless ATMNetworks(WANs). Networks are managed via one of the following twomethods; the centralized connection management where a connectionserver performs network connection management, and the distributedconnection management where each node performs network connectionmanagement. The two methods have their own drawbacks. Whereconnection management is performed in a centralized manner,propagation delay occurs. Distributed connection management leadsto increased overall system overhead. For reducing thoseproblems, we propose a Distributed Anchor CX Searching algorithm.Within networks that are grouped together, connection managementis done for each group by anchor switches, and Permanent VirtualCircuit (PVC) with a narrow bandwidth is assigned between anchorsfor exchange of information. The proposed algorithm enables quicksearching of a targeted CX, makes management of the overallnetwork easier, and reduces system overhead.
      Performance Improvement Scheme of NIDS through Optimizing Intrusion Pattern Database. Jae-Myung Kim, Kyu-Ho Lee, Jong-Seob Kim, Kuinam J. Kim
        This paper aims to present a separated, optimizedpattern database classification model, which may be subsequentlyapplied to improve Network-based Intrusion Detection System (NIDS)efficiency. Using the model that classification basis isdetermined by examining the validity of a specific intrusion on agiven specific target, NIDS is able to search only valid patternsin each captured packet of pattern database. In terms ofperformance and results, the NIDS resource requirement forpattern database searches is reduced and the NIDS is able toanalyze more valid packets.



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