Conference Abstracts

Group C: Computing and Transport Systems

Session 9: Optical and Wireless Communications I

Session 12: Optical and Wireless Communications II

Session 15: Image and Signal processing I

Session 17: Intelligent Information Processing I

Session 18: Image and Signal processing II

Session 20: Intelligent Information Processing II

Session 21: Optical and Wireless Communications III

Session 9: Optical or Wireless Communications I

9-1 Title Joint MMSE frequency-domain equalization and ICI cancellation for multicode DS-CDMA
Author(s) Kazuaki Takeda and Fumiyuki Adachi
Abstract The bit error rate (BER) performance of DS-CDMA in a frequency-selective fading channel can be significantly improved by the use of frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion. However, the presence of residual inter-chip-inference (ICI) after FDE produces the orthogonality distortion among the spreading codes and the BER performance degrades. In this paper, we propose a joint MMSE-FDE and ICI cancellation to improve the BER performance. The MMSE weight at each iteration is derived taking into account the residual ICI. The effect of the proposed ICI cancellation scheme is confirmed by computer simulation.

9-2 Title MAI-free DS-CDMA with 2-Dimensional Block Spreading
Author(s) Le Liu and Fumiyuki Adachi
Abstract Multi-access interference (MAI) limits the transmission performance of the DS-CDMA uplink. In this paper, we propose a 2-dimensional (2D) block spreading to transform the multi-user channel into orthogonal single-user channels. Due to MAI cancellation, 2D block spread DS-CDMA has ability to increase the link capacity as well as to provide multi-rate services. Single-user frequency-domain equalization based on the minimum mean square error (MMSE) criterion is applied for signal detection. The transmission performance in a multiuser and frequency-selective fading environment is evaluated by computer simulation.

9-3 Title Overlap FDE for multi-code MC-CDMA
Author(s) Hiromichi Tomeba, Kazuaki Takeda and Fumiyuki Adachi
Abstract Multi-carrier code division multiple access (MC-CDMA) has been attracting much attention for the next generation mobile communication systems. MC-CDMA requires the insertion of the guard interval (GI) to avoid the inter-block interference (IBI); however, the GI insertion reduces the transmission efficiency. In this paper, a frequency-domain equalization (FDE) technique, called overlap FDE, which requires no GI insertion, is presented for multi-code MC-CDMA transmission. The achievable BER performance with overlap FDE in a frequency-selective block Rayleigh fading channel is evaluated by computer simulation.

9-4 Title A Broadband Wireless Communication Scheme for 60GHz band
Author(s) Shoichi Oshima, Goro Mori, N.H Tran, Hiroshi Oguma, Suguru Kameda, Hiroyuki Nakase, Tadashi Takagi and Kazuo Tsubouchi
Abstract High data transmission rates that exceed 1Gbps in wireless communication system require high device performance, e.g., A/D converters to operate at high sampling rates, wide bandwidth and high power efficiency to achieve conventional power consumption. We also have to consider which band can be used because the system requires a very broad bandwidth. One of the available bands is the 60GHz band, where a 2GHz bands is available without licenses. In this paper, we propose a broadband wireless communication scheme for the 60GHz band. Data rates exceeding 2Gbps can be achieved without extremely high device performance.

9-5 Title Optical phase-locked loop for coherent transmission over 500 km using heterodyne detection with fiber lasers
Author(s) Keisuke Kasai, Masato Yoshida and Masataka Nakazawa
Abstract We have successfully achieved an OPLL system for coherent transmission over 500 km using heterodyne detection, in which we used a 13C2H2 frequency-stabilized fibre ring laser as a transmitter and a high-speed free running fibre laser with an LN modulator as an LO. With this configuration, we obtained an IF signal with a phase error variance of only 7.9~10-3 rad.

9-6 Title 10 Gb/s x 4 channel WDM transmission over a 5 km-long photonic crystal fiber in the 800 nm region
Author(s) Hideaki Hasegawa, Yosuke Oikawa, Toshihiko Hirooka, Masato Yoshida and Masataka Nakazawa
Abstract We describe 10 Gb/s x 4 channel WDM transmission over 5 km at 850 nm using a single-mode photonic crystal fiber (PCF), a vertical cavity surface emitting laser (VCSEL), and a Si-avalanche photodiode (APD). The fabricated PCF has an endlessly single-mode property. The group velocity dispersion of the PCF was -62.8 ps/nm/km, which was 35 ps/nm/km smaller than that of a conventional step-index fiber (SIF). We employed a special arrayed-waveguide grating (AWG) as a multiplexer and a demultiplexer. Power-penalty-free transmission was successfully achieved.

Go to TOP of this page

Session 12: Optical or Wireless Communications II

12-1 Title Effect of Antenna Location on Indoor MIMO System
Author(s) Xiao Peng YANG, Qiang CHEN and Kunio SAWAYA
Abstract The effect of antenna location on the multiple input multiple output (MIMO) communication system is investigated in line of sight (LOS) and none line of sight (NLOS) indoor environment. The channel capacity, the received power and the effective degrees of freedom (EDOF) of multipaths are statistically analyzed. It is found that MIMO channel capacity is affected significantly by antenna location.

12-2 Title Turbo coded HARQ throughput performance for SC-MIMO multiplexing with iterative FDSD
Author(s) Akinori Nakajima and Fumiyuki Adachi
Abstract One of the promising techniques to allow high-speed data transmission with a limited bandwidth is multi-input multi-output (MIMO) multiplexing. As a signal separation scheme, an iterative frequency-domain parallel detection (FDPD) using frequency-domain equalization (FDE) was recently proposed. In FDPD, the FDE and frequency-domain interference cancellation (FDIC) are repeated a sufficient number of times. However, since signal detection for all antennas is done simultaneously, the received signal having higher interference limits the performance improvement. In this paper, we propose the iterative frequency-domain successive detection (FDSD) and investigate, by computer simulation, the transmission performances in a frequency-selective Rayleigh fading channel.

12-3 Title Accuracy of Analyzing MIMO propagation channel by using Ray Launching Method
Author(s) Takanori Iwaki, Qiang Chen and Kunio Sawaya
Abstract The error of the channel capacity in MIMO system caused by the use of ray launching method is described. It is found that the average channel capacity increases as the angle between adjacent rays in the ray launching increases. On the other hand the average capacity obtained by the ray launching method is almost the same to the exact solution when spatial correlation of the propagation channel is low.

12-4 Title Performance of OFDM/TDM with Pilot-assisted Channel Estimation
Author(s) Haris Gacanin and Fumiyuki Adachi
Abstract Orthogonal frequency division multiplexing combined with time division multiplexing (OFDM/TDM) can overcome the high peak-to-average-power ratio (PAPR) problem of conventional OFDM. OFDM/TDM requires accurate channel estimation (CE). In this paper, pilot-assisted CE for OFDM/TDM with MMSE-FDE is studied. The achievable BER performance is evaluated by computer simulation.

12-5 Title Numerical Analysis of Electromagnetic Waves Using 3-D FDTD-CIP Hybrid Method
Author(s) Jerdvisanop Chakarothai, Qiang Chen and Kunio Sawaya
Abstract In this research, Constrained Interpolation Profile(CIP) method which was proposed by Yabe, method of characteristics and ime splitting method are applied to electromagnetic field equation (Maxwell's equation) including complex permittivity and permeability. CIP method is combined with FDTD method to reduce the phase delay of propagation. The calculated result in analysis domain is compared to that by FDTD method. From results of CIP method, the phase delay of propagation is decreased when compared that of FDTD method. Also the model including array antenna is calculated to prove the validity of CIP method in electromagnetic field analysis.

Go to TOP of this page

Session 15: Image and Signal processing I

15-1 Title Error robust transmisson for speech signal using Multiple Description Quantization
Author(s) Ho-Seok Wey, Ryouichi Nishimura and Yoiti Suzuki
Abstract Typically current network systems work with TCP that controls retransmission of lost packets. Though these techniques are well suited to many applications, putting them together can produce some delays when packets are lost. TCP-based content delivery suffers from the reconstruction stalls because the delay in receiving a retransmitted packet may be much longer than the inter-arrival times between received packets. To avoid these kind of the problem, gMultiple Description codinghis recently attracting attention as the alternatives of the guaranteed transmission method of media-data on the network. So, I examined the possibility of the Multiple description coding.

15-2 Title Estimation of sound source positions using a surrounding microphone array
Author(s) Takuma OKAMOTO, Ryouichi NISHIMURA and Yukio IWAYA
Abstract We developed FIR^3 (Field Recording, Recognition and Reproduction) system to record and reproduce a sound field, with the goal of reconstructing the sound information of the room in another space at another time. In this system, a surrounding microphone array is used to record a sound field. A method for detecting sound source positions using this microphone array is needed. We developed a method in which the MUSIC algorithm and the spatial-smoothing technique are integrated and named it ``Rearrangement And Pre-smoothing for MUSIC (RAP-MUSIC)''. Using this method, source positions in a reverberant room can be detected accurately.

15-3 Title Design of a Fluid Analysis Simulator Based on Lattice Gas Cellular Automaton
Author(s) Daisuke Suzuki and Takahiro Hanyu
Abstract This paper presents a fluid analysis simulator based on lattice gas cellular automaton (LGCA), whose basic function is represented by using collision rules between near-neighbor-virtual particles corresponding to cells. By changing collision rules, any types of LGCA schemes together with setting up any boundary conditions can be performed. The proposed hardware structure is extendable to any size required for fluid analysis,because of its cellular array VLSI configuration. Since the proposed architecture is based on local connection with near-neighbor cells, it is suitable for hardware implementation using a field programmable gate array (FPGA), and the usefulness is discussed.

15-4 Title An Arithmetic Module Generator Based on Arithmetic Description Language: ARITH
Author(s) Yuki Watanabe, Naofumi Homma, Takafumi Aoki and Tatsuo Higuchi
Abstract This paper proposes an arithmetic module generator based on arithmetic description language called ARITH. The use of ARITH makes possible (i) formal description of arithmetic algorithms including those using unconventional number systems, (ii) formal verification of described arithmetic algorithms, and (iii) translation of arithmetic algorithms to equivalent HDL codes. The proposed generator supports 384 types of arithmetic algorithms and produces reliable modules whose functions are completely verified in a formal verification method.

15-5 Title Nonvolatile Static Latch Based on Ferroelectric Defferential Logic
Author(s) Shoun Matsunaga and Takahiro Hanyu
Abstract A nonvolatile static latch using ferroelectric capacitors is proposed for standby-power-free VLSI. A key circuit technique is dynamic-logic-based differential-pair circuitry which performs not only high-speed but also low-power operation at active mode. At standby mode, power supply in the proposed latch is entirely removed because of a nonvolatile storage capability due to ferroelectric capacitors, so that standby-power becomes free. It is evaluated with HSPICE that the delay and the power dissipation of the proposed latch are greatly reduced in comparison with those of an ordinary CMOS-based latch in spite of having a nonvolatile storage capability in the proposed latch.

15-6 Title A Closed Form Solution to L2-Sensitivity Minimization of Second-Order Digital Filters Subject to L2-Scaling Constraints
Author(s) Shunsuke Yamaki, Masahide Abe, and Masayuki Kawamata
Abstract This paper proposes a closed form solution to L2-sensitivity minimization of 2nd-order state-space digital filters subject to L2-scaling constraints. The proposed solution reduces a constrained optimization problem to an unconstrained optimization problem by appropriate variable transformation. Furthermore, by restricting ourselves to the case of 2nd-order state-space digital filters, we can formulate the L2-sensitivity minimization problem via hyperbolic functions. As a result, we can express the L2-sensitivity in closed form, whose minimization subject to L2-scaling constraints is achieved without iterative calculations.

15-7 Title A Simplex/Duplex-Compatible System for Asynchronous Peer-to-Peer Communication Using One-phase Signaling
Author(s) Tomohiro Takahashi and Takahiro Hanyu
Abstract This paper presents an asynchronous peer-to-peer simplex/duplex-compatible communication system based on a 1-phase signaling scheme that is high-speed and robust to variations of wire delays. A transmission is controllable by adding a mode-detection channel that observes the mutual states in both ends. Since current sources are appropriately controlled depending on mutual states, the power dissipation can be greatly reduced when both ends are on standby. Moreover, both simplex and duplex communication can be realized by sharing a common circuit except a signal-level conversion circuit. The proposed interface is implemented using 0.18-ƒÊm CMOS, and its performance and efficiency are discussed.

Go to TOP of this page

Session 17: Intelligent Information Processing I

17-1 Title A Program Transformation System for Developing Reliable Software
Author(s) Yuki Chiba, Takahito Aoto and Yoshihito Toyama
Abstract Chiba et al. (2005) proposed a framework of program transformation bytemplate and automated verification of its correctness based on term rewriting. This paper describes a design and implementation of RAPT which implements this framework. RAPT transforms a term rewriting system according to a specified program transformation template. Presupposing the program transformation template is developed, the correctness of the transformation is automatically verified so that the transformation keeps the relationship between initial ground terms and their normal forms.

17-2 Title Type-based Resource Usage Verification
Author(s) Futohshi Iwama
Abstract It is an important criterion of program correctness that a program accesses resources in a valid manner. For example, a file that has been opened should be eventually closed, and some methods of an object must be invoked in a specific order. So far, most of the methods to verify this kind of property have been proposed in rather specific contexts (like studies of memory management and verification of lock primitives). We formalize a general problem of verifying resource usages as resource usage verification in lambda calculus including resources and exceptions, and proposed a type-based method to solve the resource usage verification problem.

17-3 Title Development of real-time tunable spring for autonomous mobile robots and next-generation information electronics
Author(s) Takuya Umedachi and Akio Ishiguro
Abstract Traditionally, robot design has been done typically highly focusing on control system. However, ``well-balanced" coupling between control and mechanical systems should be considered. Additionally, the ``meeting point" between the two systems should be varied according to the environment encountered. To this end, this study particularly focuses on the stiffness of robots' joints, since this strongly contributes to tuning the dominance relationship between control and mechanical systems. More specifically, the aim of this study is to develop a ``Real-time tunable spring" that can change its elasticity without changing its natural length, allowing robot's joints to change their position and stiffness independently.

17-4 Title Efficient and Adaptive Control of Walking Biped by Exploiting a Pulsed-CPG
Author(s) Dai Owaki, Yoshiyuki and Akio Ishiguro
Abstract Recently, it has been widely recognized that control and mechanical systems cannot be designed separately due to their tight interdependency. However, there still leaves much to be understood about how well-balanced coupling between control and mechanical systems can be achieved. In light of these facts, this study proposes a pulsed-CPG that can generate discrete control outputs according to the situation. In order to verify the feasibility, we implement the pulsed-CPG to a walking biped as a practical example. Preliminary simulation results strongly support that the pulsed-CPG can enhance robustness against perturbations while maintaining efficient walking.

17-5 Title A Lower Bound for Feedfoward Neural Networks with Small Energy Consumption
Author(s) Kei Uchizawa and Eiji Takimoto
Abstract Recently, a complexity measure for threshold circuits called the energy complexity has been proposed to model the amount of energy consumed during a computation in the brain. Formally, the energy complexity is the maximum number of firing gates over all inputs. Motivated by the fact that the firing activity of neurons in the brain is quite sparse, we investigate what functions can or cannot be computed by threshold circuits with small energy complexity. More precisely we give an inequality on three complexity measures energy complexity, size, and depth, of threshold circuits; the inequality implies a tradeoff among three complexity measures.

17-6 Title On formula size lower bounds for synthesis of Boolean functions over disjoint sets of variables
Author(s) Hideaki Fukuhara, Kazuyuki Amano and Eiji Takimoto
Abstract Recently, it turned out that a complexity measure for Boolean functions called sumPI proposed in quantum computing provides a good lower bound on the formula size. We evaluate sumPI(f ƀ g) in terms of sumPI(f) and sumPI(g), where f and g are "disjoint" Boolean functions, i.e., the sets of variables forf and g are disjoint,and ƀ is an arbitrary Boolean operator.This recursively generates formula size lower bounds for synthesis of disjoint Boolean functions. Moreover, under some condisions the bounds exactly give the formula size complexity.

17-7 Title A Dynamic QoS Control Scheme for 3-D Virtual Space Based on User's Perception
Author(s) Takayuki Kuroda, Takuo Suganuma and Norio Shiratori
Abstract Generally, 3D-Virtual Environment (3DVE) needs powerful image processing capability and ultra high-speed, high-capacity network environment. Therefore, dynamic and adequate QoS control is required under the situation where computer and network resources are changing. In this paper, we propose an effective QoS control scheme that introduces characteristics of user's perceptual quality evaluation on 3-D objects. This scheme can appropriately maintain quality and functions of 3DVE, and is expected to drastically improve convenience when using it under the situation that the resources are limited. Experimental results obtained from prototype system show effectiveness of our scheme on the diverse computer and network situations.

Go to TOP of this page

Session 18: Image and Signal processing II

18-1 Title Estimation of Motion Vector Fields under Brightness Variations
Author(s) Sang-Churl NAM, Masahide ABE and Masayuki KAWAMATA
Abstract This paper presents a robust algorithm for the estimation of 2-D motion vector fields in the presence of brightness variation. To cope with undesirable motion estimation due to illumination changes of image sequences, brightness variation parameters are first estimated under the assumption that the parameters are locally constant, and then motion vector fields are estimated. To illustrate the effectiveness of the proposed approach, simulation results are shown for test sequences with brightness variations.

18-2 Title Super-Resolution Using Phase-Based Image Matching and Its Application to Deinterlacing
Author(s) Norihito Numa, Takafumi Aoki and Satoshi Kondo
Abstract This paper presents super-resolution using phase-based image matching, and its application to deinterlacing of video sequences. Super-resolution is a resolution enhancement method that reconstructs a high-resolution image from multiple low-resolution images. To achieve high-quality super-resolution, it is important to estimate sub-pixel displacement between images accurately. In this paper, we employ phase-only correlation (POC) for sub-pixel displacement estimation, and reconstruct a high-resolution image using block-based super-resolution. We apply this technique to deinterlacing of video sequences, and evaluate its performance.

18-3 Title Enlargement for Images with Gaussian Noise by Embedded Filtering in the LP Algorithm
Author(s) Shuai Yuan, Akira Taguchi, Masahide Abe and Masayuki Kawamata
Abstract In this paper, we propose an enlargement method for images with Gaussian noise based on the Laplacian pyramid (LP) representation. Unlike lowpass pre-processing approaches to the LP enlargement method, an embedded approach is used in this paper. Since the amplitude of Gaussian noise signals is smaller than the amplitude of image edge signals in the predicted LP stage, we adopt a modified ƒÃ-filter in the proposed LP enlargement algorithm to reduce the Gaussian noise. Experimental results show that the proposed method can obtain high accuracy denoise enlarged images.

18-4 Title 3D Face Recognition System Using Passive Stereo Vision
Author(s) Akihiro Hayasaka, Takuma Shibahara, Koichi Ito, Takafumi Aoki, Hiroshi Nakajima and Koji Kobayashi
Abstract This paper proposes a three-dimensional (3D) face recognition system using passive stereo vision. So far, the reported 3D face recognition systems assume the use of active 3D measurement for 3D facial capture. However, active methods employ structured illumination or laser scanning, which is not desirable in many human recognition applications. Addressing this problem, we propose a 3D face recognition system that uses (i) AdaBoost-based face detector to automatically extract a face region from an image and (ii) passive stereo vision to capture 3D facial information. Experimental evaluation demonstrates an efficient recognition performance of the proposed system.

18-5 Title Codebook Design by Classification of Code Patterns for Human Face Recognition
Author(s) Qiu Chen, Koji Kotani, Feifei Lee and Tadahiro Ohmi
Abstract In this paper, we present a novel Codebook design method to improve the face recognition rate for VQ histogram method, a very simple yet highly reliable face recognition method which has been developed previously. Based on the systematic classification and organization of code patterns, we theoretically create the most suitable codebook consisted of 2x2 codevector. Experimental results show face recognition using such a codebook is more efficient than the codebook consisted of 4x4 codevector used in conventional algorithm. Furthermore, Processing time for single image is about 3 times faster than the conventional method.

18-6 Title Robust Shot Change Detection in MPEG Compressed Video Based on Adjacent Pixel Intensity Difference Quantization Histogram Method
Author(s) Feifei Lee, Koji Kotani, Qiu Chen and Tadahiro Ohmi
Abstract Previously, we have developed a very simple yet highly reliable face recognition method called adjacent pixel intensity difference quantization (APIDQ) histogram method. In this paper, we present a novel shot change detection algorithm for MPEG compressed video based on the algorithm above. Instead of fully decompressed video frames, partially decoded data, namely DC images are utilized. Experimental results show the APIDQ histogram method is very efficient for shot change task than the conventional approaches. Moreover, shot change detection on MPEG compressed data is performed approximately 3 times faster than real time processing speed.

Go to TOP of this page

Session 20: Intelligent Information Processing II

20-1 Title A hardware BP system for high speed inspection
Author(s) Seungwoo Chun, Yoshihiro Hayakawa and koji Nakajima
Abstract At factories, the surface inspection of final products relies on visual inspection, which is based on experience and instinct. With such method it is difficult to reduce time and production cost, and hence an automatic inspection system is desired. We use a hardware neural network enabling high-speed judgment and learning. In order to increase the operation speed, we have implemented parallel and pipeline processing in the hardware. For exemple, the visual inspection by humans of gilding terminals on a small size board takes about two seconds for each product. However, our hardware neural network system can complete the process within 0.1 second.

20-2 Title Reaching Control in Indefinite Environment by Constraints Emergence and Satisfaction
Author(s) Yuki Yoshihara, Nozomi Tomita, Yoshinari Makino and Masafumi Yano
Abstract Human reaching movement is accomplished even when environmental conditions unexpectedly change in the real world. Since human arm is a redundant system, constraints must be introduced to determine a unique motor command, and simultaneously those should be changed flexibly to adapt to external forces or varying dynamical properties of the arm. In this paper, as the constraint, a desired hand velocity is introduced because it can be reset with any environmental changes in real-time. The proposed model determines angular velocity of each joint that satisfies the constraint in distributed autonomous way, and achieves robust control in unpredictably changing environment.

20-3 Title Design and Implementation of A Real-time Watch-over System for Ubiquitous Information Environment
Author(s) Hideyuki Takahashi, Yoshikazu Tokairin, Kazuhiro Yamanaka, Gen Kitagata, Takuo Suganuma and Norio Shiratori
Abstract In this paper we propose a real-time system for watching over for ubiquitous care-support services that fulfill users' actual requirements. In traditional systems of this domain, only the location information of a user on "one" side of the watching site or the watched site is considered. In this work, we cope not only with the user's location but also all the detailed situations (contexts) of associated entities such as devices, software, networks, and users, in "both" sides. We designed and implemented a prototype for watching over elderly people, and performed some experiments based on several scenarios.

Author(s) Sameera Abar, Susumu Konno, Takahiro Uchiya, Yukio Iwaya, Toru Abe and Tetsuo Kinoshita
Abstract Pre-requisite for the automation of network management functions is the detailed interpretation of the network-related knowledge resources. This paper proposes a novel artificial intelligence based knowledge acquisition, representation and utilization scheme, to support the active management of communication network systems. Our emphasis has primarily been on the modularization of resource knowledge to facilitate its reuse in a flexible manner. For a proof of concept, an experimental network system has been implemented, and the deployment of some test-bed scenarios is performed.

20-5 Title An Automatic User Authentication System Using Face Recognition
Author(s) Yin Dongzhu, Omachi Shinichiro and Aso Hirotomo
Abstract One of the most conventional authentication method is password, which is very simple and does not require any special device. However, it can be easily divulged by others. To tackle this problem, in this paper we present an approach for the user authentication system using face recognition techniques. To localize and segment face region in the input image we employed color information and multi-scale template matching method. To identify each individual we used combination of color information and the principal component analysis (PCA) method.

Go to TOP of this page

Session 21: Optical or Wireless Communications III

21-1 Title Implementation of a High-Throughput LDPC Decoder Chip Using an Asynchronous Interleaving Scheme
Author(s) Naoya Onizawa and Takahiro Hanyu
Abstract Data-transfer bottleneck between computation nodes inside a low-density parity-check (LDPC) decoder chip is a serious problem in next-generation communication systems such as IEEE 802.16 and 10GBASE-T. This paper presents an implementation of a LDPC decoder based on full-duplex asynchronous interleaving. The use of an asynchronous interleaver makes it possible to avoid clock-skew problems. Moreover, both control signals and data are directly represented by a multi-level current signal, asynchronous full-duplex communication can be performed by just 2 wires. As a result, throughput is increased by 20% with respect to a conventional scheme for a similar coding gain.

21-2 Title A New QoS Routing Scheme for Mobile Ad Hoc Networks
Author(s) Toshiaki Osada, Gen Kitagata, Debasish Chakraborty, Takuo Suganuma and Norio Shiratori
Abstract In this paper, we propose an Application-level QoS Routing Scheme for MANETs (ALRS), that includes three significant features: (1) estimation of consumed bandwidth on each node using 2-hop neighbors' traffic information, (2) route construction combined with admission control per session using (1), and (3) route maintenance based on (1) and (2). ALRS realizes control of application traffic in MANET effectively and enables to provide the service to satisfy required quality for dynamic changes of network resources. By using ALRS, it is expected that availability of bandwidth will be greatly improved for heavy traffic communication, such as multimedia application on MANET.

21-3 Title Applications of List Colorings to Scheduling Problems
Author(s) Yuki Matsuo, Xiao Zhou and Takao Nishizeki
Abstract A list total-coloring problem is one of graph coloring problems and has a large number of applications, especially for scheduling problem, time tabling problem, frequency assignment problem and so on. We consider a list total-coloring for series-parallel graphs. A series-parallel graph represents a network obtained by repeating series connection and parallel connection, and often appears in many practical applications. We obtain two sufficient conditions for a series-parallel graph to have a list total-coloring and a linear-time algorithm to find a list total-coloring if any of the two conditions holds.

21-4 Title Real-Time Log Summarizing Method for Network Event Recognition
Author(s) Masahiro Nagao, Gen Kitagata, Takuo Suganuma and Norio Shiratori
Abstract In this paper, we propose a log summarizing method to help a network manager to recognize and handle a network event smoothly. Our method can accurately extract only necessary information from massive application logs in real-time by stepwise information extraction technique. This feature can help the network manager to handle an event quickly with less management burden, especially it is suitable for ultra high-speed, high-capacity network system. With our experimental results, we show that our method has the ability to remove more than 60% - 90% unnecessary records without losing any necessary information.

Go to TOP of this page