This paper concerns recognizing 3-dimensional object using proposed multi-layer block model. In particular, we aim to achieve desirable recognition performance while restricting the computational load to a low level using 3-step feature extraction procedure. An input image is first precisely partitioned into hierarchical layers of blocks in the form of base blocks and overlapping blocks. The hierarchical blocks are merged into a matrix, with which abundant local feature information can be obtained. The local features extracted are then employed by the kernel based support vector machines in tournament for enhanced system recognition performance while keeping it to low dimensional feature space. The simulation results show that the proposed feature extraction method reduces the computational load by over 80% and preserves the stable recognition rate from varying illumination and noise conditions.
Takao OGURA Junji SUZUKI Akira CHUGO Masafumi KATOH Tomonori AOYAMA
As use of the Internet continues to spread rapidly, Traffic Engineering (TE) is needed to optimize IP network resource utilization. In particular, load balancing with TE can prevent traffic concentration on a single path between ingress and egress routers. To apply TE, we have constructed an MPLS (Multi-Protocol Label Switching) network with TE capability in the JGN (Japan Gigabit Network), and evaluated dynamic load balancing behavior in it from the viewpoint of control stability. We confirmed that with this method, setting appropriate control parameter values enables traffic to be equally distributed over two or more routes in an actual large-scale network. In addition, we verified the method's effectiveness by using a digital cinema application as input traffic.
Oleg KOUDRIAVTSEV Serguei MOISEEV Mutsuo NAKAOKA
This paper presents an effective approach for estimating of the load matching conditions for dielectric barrier discharge (DBD) load. By the simulation method proposed here, optimal working frequency and optimal applied voltage for driving of DBD load can be calculated. Estimation results for the DBD ultraviolet generation lamp as a load of series resonant inverter are presented here, together with their evaluations.
Software Defined Radio is beyond the education and initiation phase. The industry is addressing the needs of reconfigurable radio technology development, implementation, and application in a variety of marketplaces. Regulatory decisions are being formulated to facilitate SDR adoption and deployment. Continued dialog and cooperation among the industry organizations is an important factor in the rate of progress.
Hironori UCHIKAWA Kenta UMEBAYASHI Ryuji KOHNO
In this paper, we focus attention on the development of security techniques using software defined radio (SDR) technologies. We propose a new secure download system which uses the characteristics of the field programmable gate arrays (FPGAs) composing the SDR. The proposed system has the novelty that realization of high security encipherment is possible. This is achieved using the characteristic of FPGAs which allows systems to be arranged in a variety of different layouts, as well as by using the configuration information as the key. This unifies the renewal of the key and the encipherment. In addition the proposed system has the merit that it has high security against illegal acquisition such as a wiretapping, and can also be used in conjunction with any other current cipher algorithm. As an evaluation of the security, we show that the proposed system has high immunity to illegal acquisition of software using replay attack, by verification of the protocol as well as by numerical computation. The proposed system can therefore realize high security software downloads based on SDR.
Hiroyuki SHIBA Takashi SHONO Yushi SHIRATO Ichihiko TOYODA Kazuhiro UEHARA Masahiro UMEHIRA
A software defined radio (SDR) prototype based on a multiprocessor architecture (MPA) is developed. Software for Japanese personal handy phone system (PHS) of a 2G mobile system, and IEEE 802.11 wireless LAN, which has much wider bandwidth than the 2G systems, is successfully implemented. Newly developed flexible-rate pre-/ post-processor (FR-PPP) achieves the flexibility and wideband performance that the platform needs. This paper shows the design of the SDR prototype and evaluates its performance by experiments that include PHS processor load and wireless LAN throughput characteristics and processor load.
Lei DENG Shigeaki TAGASHIRA Satoshi FUJITA
In this paper, we propose a new job scheduling method for distributed parallel systems that can simultaneously achieve two main goals of the job scheduling in those systems: to minimize the execution time of a parallel job without disturbing the execution of the other jobs. We try to achieve those goals by introducing a new scheduler, called active scheduler, that dynamically controls the priority of parallel programs and balances the workload of host computers depending on the status of the underlying runtime environment. We implemented a prototype system of the scheduler to evaluate its effectiveness. The result of experiments implies that the overhead of introducing the active scheduler is at most 15% of the original execution time, and it is in fact effective to adjust the execution of parallel programs to an actual distributed environment in which many users execute their jobs simultaneously.
In this paper, we study a low profile top loaded monopole antenna. By changing the number, thickness, position and shape of post(s), the input and radiation characteristic due to parameters of matching post(s) are investigated. The low profile top loaded monopole antenna (TLMA) is known as a suitable way for antenna's miniaturization. But it is also reported that the parameters of matching post influence the input and radiation characteristic greatly. The FDTD method is well suit for use in analyzing both the plate and wire structure. And to improve the calculation effect efficiency, the non-uniform mesh FDTD algorithm is used. From the measurement and simulation results, we propose the most suitable parameters of matching structure for low profile top loaded monopole antenna.
Load/unload techniques are widely used in mobile hard disk drives which have to endure external shocks frequently. ABS designs must consider both the load/unload performance and the shock resistance performance. Three ABS designs with different positions of the suction force center are studied in simulation. It is observed that when the position of the suction force center moves frontward, the anti-shock performance improves, but the unload performance degrades, and vice versa. A slider is not necessary to be designed to have its suction force center significantly behind of its geometric center, as the traditional load/unload sliders do. Instead, the suction force center can be designed near the geometric center if the hook limiter is used.
In this paper, a novel type of neural networks called grey neural network (GNN) is proposed and applied to improve short term load forecasting (STLF) performance. This work is motivated by the following observations: First, the forecasting performance of neural network is affected by the randomness in STLF data. That is, poor performance results from large randomness and vice versa. Second, the grey first-order accumulated generating operation (1-AGO) is reported having randomness reduction property. By the observations, the GNN is proposed and expected to have better STLF performance. The GNN consists of grey 1-AGO, the piecewise linear neural network (PLNN), and grey first-order inverse accumulated generating operation (1-IAGO). Given a set of STLF data, the data is first converted by grey 1-AGO and then is put into the PLNN to perform forecasting. Finally, the predicted load of GNN is obtained through grey 1-IAGO. For comparison, the original STLF data is also put into the PLNN itself. With identical training conditions, the simulation results indicate that with various network structures the GNN, as expected, outperforms the PLNN itself in terms of mean squared error.
Hiroshige OHNO Hiroshi NARUSE Toshio KURASHIMA Atsushi NOBIKI Yasuomi UCHIYAMA Yuki KUSAKABE
We applied a Brillouin-OTDR, which is a distributed optical fiber strain sensor, to two actual concrete piles. The piles were made for use as highway foundations by on-site-pouring at construction sites and underwent load testing to ensure that their characteristics satisfied the required levels. Compressive strain caused by the load exerted on the piles was measured to an accuracy of 0.01% and a spatial resolution of 1 m. This measurement was obtained by embedding a strain-sensing optical fiber in the piles during construction. The results showed that there was good agreement between the measured strain and both the theoretical values and the values obtained with a conventional strain gauge based on electric resistance. Furthermore, the obtained strain distribution reflected the effects of friction between the pile surface and the ground. These results demonstrate the effectiveness of the Brillouin-OTDR for this kind of testing and also as a means of obtaining detailed data on the strain in concrete piles.
Akiko NAKANIWA Jun TAKAHASHI Hiroyuki EBARA Hiromi OKADA
In this paper, we consider optimal mirror allocation problems for the purpose of load balancing in network servers. We focus on constructing high-reliability networks and propose the optimal mirror allocation model such that the system reliability is maximized subject to costs and delays, in view of the trade-off between the reliability and cost. This optimization model is capable of dealing with various kinds of network topologies, although for simplicity, we assume the read-only situation. We formulate this optimization problem into a 0-1 integer programming model, and we use an approximate method for numerical analysis in order to analyze more large-scale systems. Our objective is to find the optimal mirror allocation by solving this model, and to show quantitatively the general characteristics of the load balancing and the improvement of the system reliability by the distributed mirror allocation.
Naohiko IRIE Fumio ARAKAWA Kunio UCHIYAMA Shinichi YOSHIOKA Atsushi HASEGAWA Kevin IADONATE Mark DEBBAGE David SHEPHERD Margaret GEARTY
An embedded processor core using split branch architecture has been developed. This processor core targets 400 MHz using 0.18 µm technology, and its higher frequency needs deeper pipeline than the conventional processor. To solve the increasing branch penalty problem caused by a deeper pipeline, this processor takes an active preload mechanism to preload the target instructions to internal buffers in order to hide the instruction cache latency. The processor also uses multiple instruction buffers to reduce branch penalty cycles of branch misprediction. The performance estimation result shows that about 70% of branch overhead cycles can be reduced from the conventional implementation. The area for this branch mechanism consumes only 1% of the total core, which is smaller than the conventional branch target buffer (BTB) scheme, and helps to achieve low power and low cost.
Hiroyoshi MIWA Kazunori KUMAGAI Shinya NOGAMI Takeo ABE Hisao YAMAMOTO
The explosive growth of World Wide Web usage is causing a number of performance problems, including slow response times, network congestion, and denial of service. Web site that has a huge number of accesses and requires high quality of services, such as a site offering hosting services, or content delivery services, usually uses a cache server to reduce the load on the original server offering the original content. To increase the throughput of the caching process and to improve service availability, multiple cache servers are often positioned in front of the original server. This requires a switch to direct incoming requests to one of the multiple cache servers. In this paper, we propose a routing algorithm for such a switch in front of clustered multiple cache servers and evaluate its performance by simulation. The results show that our routing algorithm is effective when content has request locality and a short period of validity, for example, news, map data, road traffic data, or weather information. We also identify points to consider when the proposed algorithm is applied to a real system.
Hiroyuki OKAMURA Satoshi MIYAHARA Tadashi DOHI Shunji OSAKI
The software rejuvenation is one of the most effective preventive maintenance technique for operational software systems with high assurance requirement. In this paper, we propose the workload-based software rejuvenation scheme for a server type of software system, and develop stochastic models to determine the optimal software rejuvenation schedules for some dependability measures. In numerical examples, we evaluate quantitatively the performance of workload-based software rejuvenation scheme and compare it with the time-based rejuvenation scheme.
Autonomous Information Service System is a proposition made to cope with the continuously changing conditions of service provision and utilization in current information systems. The faded information field (FIF), sustained by push/pull mobile agent technology, is such a distributed architecture that brings high-assurance of the system through a balanced selective replication of the information. When the demand changes, the information environment is restructured so that the same response time to services for all unspecified users can be achieved whatever the demand volume. However, once the structure is fixed, dispatching the randomly incoming requests on the FIF is still required to guarantee the same quality of service. Our goal is to warrant the autonomous dispatching of the pull mobile agents to adjust the continuously evolving arrival distribution of the demand to the current information environment. In this paper, we explain the concepts and realization of autonomous navigation under the goal of an autonomous load balancing of the pull mobile agent volume in the FIF structure. The appropriateness of this method for FIF environments has been shown by simulation.
Won-Ki PARK Young-Soo SOHN Jin-Seok PARK Hong-June PARK Soo-In CHO
An analytic equation was derived for the time jitter of digital NRZ signals due to inter-symbol interference in the PCB transmission lines loaded by DRAM chips which are located in uniform spacing. The inter-symbol interference is caused by a low-pass filtering effect of the loaded transmission line. Good agreements were observed between the equation and measurements with an average error of 17.5%.
Ichirou IDA Takatoshi SEKIZAWA Hiroyuki YOSHIMURA Koichi ITO
The efficiency-fractional bandwidth product (EB), which is expressed as a ratio of the radiation resistance to the absolute value of the input reactance of an antenna, is used as a performance criterion for small dielectric loaded monopole antennas (DLMAs). The dependence of the EB on the permittivity of the dielectric loading (i.e., the electrical volume) is experimentally and numerically investigated for the first time in antenna research. As a result, it is found that the EBs of the some DLMAs are enhanced over a bare monopole antenna and an EB characteristic curve has a maximum point. This result suggests the presence of the optimum electrical volume for the dielectric loading in order to obtain the best EB performance. A general reason for the existence of the peak value is also explained using a mathematical deduction. Finally the system EB, which is an efficiency-fractional bandwidth product of the DLMA with a practical matching circuit, is defined and its dependence on the relative permittivity is illustrated. Consequently, the existence of the peak value is also confirmed for the system EBs. In addition, it is demonstrated that the enhancement of the system EB is mainly due to the enhancement in the efficiency of the antenna system.
In this paper, an attempt was made to evaluate mental workload using chaotic analysis of EEG. EEG signals registered from Fz and Cz during a mental task (mental addition) were recorded and analyzed using attractor plots, fractal dimensions, and Lyapunov exponents in order to clarify chaotic dynamics and to investigate whether mental workload can be assessed using these chaotic measures. The largest Lyapunov exponent for all experimental conditions took positive values, which indicated chaotic dynamics in the EEG signals. However, we could not evaluate mental workload using the largest Lyapunov exponent or attractor plot. The fractal dimension, on the other hand, tended to increase with the work level. We concluded that the fractal dimension might be used to evaluate a mental state, especially a mental workload induced by mental task loading.
Miki YAMAMOTO Hirokazu MIURA Kenji NISHIMURA Hiromasa IKEDA
In server load balancing where replicated servers are dispersed geographically and accesses from clients are distributed to replicated servers, a way of distributing the accesses from clients to an adequate server plays an important role from the viewpoint of load balancing. In the paper, we propose a new network paradigm for server load balancing using active anycast. In active anycast, an end user only sends its request to group of servers using an anycast address. When this request arrives at an active router, it selects an adequate server from the viewpoint of load balancing and changes the anycast address of a packet to the unicast address of the selected server. The decision which server is the best one from the viewpoint of server load balancing is made by an active router rather than an end user, so active anycast is a network-initiated method. Simulation results show that active anycast can accomplish efficient server load balancing, even when a small part of routers are equipped with active network technology.