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[Keyword] PLA(1376hit)

381-400hit(1376hit)

  • An Effective Overlap Removable Objective for Analytical Placement

    Syota KUWABARA  Yukihide KOHIRA  Yasuhiro TAKASHIMA  

     
    PAPER

      Vol:
    E96-A No:6
      Page(s):
    1348-1356

    In the recent LSI design, it is difficult to obtain a placement which satisfies both design constraints and specifications due to the increase of the circuit size, the progress of the manufacturing technology, and the speed-up of the circuit performance. Analytical placement methods are promising to obtain the placement which satisfies both design constraints and specifications. Although existing analytical placement methods obtain the placement with the short wire length, the obtained placement has overlap. In this paper, we propose Overlap Removable Area as an overlap evaluation method for an analytical placement method. Experiments show that the proposed evaluation method is effective for removing overlap in the analytical placement method.

  • Bidirectional Local Template Patterns: An Effective and Discriminative Feature for Pedestrian Detection

    Jiu XU  Ning JIANG  Satoshi GOTO  

     
    PAPER

      Vol:
    E96-A No:6
      Page(s):
    1204-1213

    In this paper, a novel feature named bidirectional local template patterns (B-LTP) is proposed for use in pedestrian detection in still images. B-LTP is a combination and modification of two features, histogram of templates (HOT) and center-symmetric local binary patterns (CS-LBP). For each pixel, B-LTP defines four templates, each of which contains the pixel itself and two neighboring center-symmetric pixels. For each template, it then calculates information from the relationships among these three pixels and from the two directional transitions across these pixels. Moreover, because the feature length of B-LTP is small, it consumes less memory and computational power. Experimental results on an INRIA dataset show that the speed and detection rate of our proposed B-LTP feature outperform those of other features such as histogram of orientated gradient (HOG), HOT, and covariance matrix (COV).

  • An Efficient Relay Placement Method with Power Allocation for MIMO Two-Way Multi-Hop Networks

    Gia Khanh TRAN  Rindranirina RAMAMONJISON  Kei SAKAGUCHI  Kiyomichi ARAKI  

     
    PAPER-Terrestrial Wireless Communication/Broadcasting Technologies

      Vol:
    E96-B No:5
      Page(s):
    1176-1186

    MIMO two-way multi-hop networks are considered in which the radio resource is fully reused in all multi-hop links to increase spectrum efficiency while the adjacent interference signals are cancelled by MIMO processing. In addition, the nodes in the multi-hop network optimize their transmit powers to mitigate the remaining overreach interference. Our main contribution in this paper is to investigate an efficient relay placement method with power allocation in such networks. We present two formulations, namely QoS-constrained optimization and SINR balancing, and solve them using a sequential geometric programming method. The proposed algorithm takes advantage of convex optimization to find an efficient configuration. Simulation results show that relay placement has an important impact on the effectiveness of power allocation to mitigate the interference. Particularly, we found that an uniform relay location is optimal only in power-limited scenarios. With optimal relay locations, significant end-to-end rate gain and power consumption reduction are achieved by SINR balancing and QoS-constrained optimization, respectively. Furthermore, the optimal number of hops is investigated in power or interference-limited scenarios.

  • Plasmonic Terahertz Wave Detectors Based on Silicon Field-Effect Transistors

    Min Woo RYU  Sung-Ho KIM  Hee Cheol HWANG  Kibog PARK  Kyung Rok KIM  

     
    PAPER

      Vol:
    E96-C No:5
      Page(s):
    649-654

    In this paper, we present the validity and potential capacity of a modeling and simulation environment for the nonresonant plasmonic terahertz (THz) detector based on the silicon (Si) field-effect transistor (FET) with a technology computer-aided design (TCAD) platform. The nonresonant and “overdamped” plasma-wave behaviors have been modeled by introducing a quasi-plasma electron charge box as a two-dimensional electron gas (2DEG) in the channel region only around the source side of Si FETs. Based on the coupled nonresonant plasma-wave physics and continuity equation on the TCAD platform, the alternate-current (AC) signal as an incoming THz wave radiation successfully induced a direct-current (DC) drain-to-source output voltage as a detection signal in a sub-THz frequency regime under the asymmetric boundary conditions with a external capacitance between the gate and drain. The average propagation length and density of a quasi-plasma have been confirmed as around 100 nm and 11019/cm3, respectively, through the transient simulation of Si FETs with the modulated 2DEG at 0.7 THz. We investigated the incoming radiation frequency dependencies on the characteristics of the plasmonic THz detector operating in sub-THz nonresonant regime by using the quasi-plasma modeling on TCAD platform. The simulated dependences of the photoresponse with quasi-plasma 2DEG modeling on the structural parameters such as gate length and dielectric thickness confirmed the operation principle of the nonresonant plasmonic THz detector in the Si FET structure. The proposed methodologies provide the physical design platform for developing novel plasmonic THz detectors operating in the nonresonant detection mode.

  • Flattening Process of Si Surface below 1000 Utilizing Ar/4.9%H2 Annealing and Its Effect on Ultrathin HfON Gate Insulator Formation

    Dae-Hee HAN  Shun-ichiro OHMI  

     
    PAPER

      Vol:
    E96-C No:5
      Page(s):
    669-673

    To improve metal oxide semiconductor field effect transistors (MOSFET) performance, flat interface between gate insulator and silicon should be realized. In this paper, flattening process of Si surface below 1000 utilizing Ar/4.9%H2 annealing and its effect on ultrathin HfON gate insulator formation were investigated. The Si(100) substrates were annealed using conventional rapid thermal annealing (RTA) system in Ar or Ar/4.9%H2 ambient for 1 h. The surface roughness of Ar/4.9%H2-annealed Si was small compared to that of Ar-annealed Si because the surface oxidation was suppressed. The obtained root mean square (RMS) roughness was 0.08 nm (as-cleaned: 0.20 nm) in case of Ar/4.9%H2-annealed at 1000 measured by tapping mode atomic force microscopy (AFM). The HfON surface was also able to be flattened by reduction of Si surface roughness. The electrical properties of HfON gate insulator were improved by the reduction of Si surface roughness. We obtained equivalent oxide thickness (EOT) of 0.79 nm (as-cleaned: 1.04 nm) and leakage current density of 3.510-3 A/cm2 (as-cleaned: 6.110 -1 A/cm2) by reducing the Si surface roughness.

  • A System-Level Network Virtual Platform for IPsec Processor Development

    Chen-Chieh WANG  Chung-Ho CHEN  

     
    PAPER-Software Engineering

      Vol:
    E96-D No:5
      Page(s):
    1095-1104

    Developing a complex network accelerator like an IPsec processor is a great challenge. To this end, we propose a Network Virtual Platform ( NetVP ) that consists of one or more virtual host (vHOST) modules and virtual local area network (vLAN) modules to support electronic system level (ESL) top-down design flow as well as provide the on-line verification throughout the entire development process. The on-line verification capability of NetVP enables the designed target to communicate with a real network for system validation. For ESL top-down design flow, we also propose untimed and timed interfaces to support hardware/software co-simulation. In addition, the NetVP can be used in conjunction with any ESL development platform through the untimed/timed interface. System development that uses this NetVP is efficient and flexible since it allows the designer to explore design spaces such as the network bandwidth and system architecture easily. The NetVP can also be applied to the development of other kinds of network accelerators.

  • Performance Measurement of Compact and High-Range Resolution 76 GHz Millimeter-Wave Radar System for Autonomous Unmanned Helicopters

    Shunichi FUTATSUMORI  Akiko KOHMURA  Naruto YONEMOTO  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E96-C No:4
      Page(s):
    586-594

    We propose a compact and high-range resolution 76 GHz millimeter-wave radar system for autonomous unmanned helicopters. The purpose of the radar system is to detect and avoid obstacles that may affect the flight safety. To achieve these objectives, a high range resolution and a long detection range are required for the radar systems with small volume and weight. The radar broadband RF front-end module which employs a simple direct conversion method is proposed. The radar module enables the 6 GHz RF signal transmission as well as the output power of about 8 dBm using commercially available low-cost monolithic microwave integrated circuits. The radar system comprises the broadband RF front-end module, a Ku-band local frequency-modulated continuous wave signal synthesizer, and a very light weight carbon fiber reinforced plastic parabolic reflector antenna. The 5 cm of range resolution is experimentally obtained using the 6 GHz RF signal bandwidth. The results of the power line measurement confirm an about 23 dB signal to noise ratio, which is measured from the reflection of the high-voltage power lines about 150 m ahead. In addition, the results of the radar system on-board test using an unmanned helicopter are evaluated. The real-time radar scope, which is transferred through the wireless connection, confirms the detection of the power lines and the other surrounding objects.

  • A Survey on Statistical Modeling and Machine Learning Approaches to Computer Assisted Medical Intervention: Intraoperative Anatomy Modeling and Optimization of Interventional Procedures Open Access

    Ken'ichi MOROOKA  Masahiko NAKAMOTO  Yoshinobu SATO  

     
    SURVEY PAPER-Computer Assisted Medical Intervention

      Vol:
    E96-D No:4
      Page(s):
    784-797

    This paper reviews methods for computer assisted medical intervention using statistical models and machine learning technologies, which would be particularly useful for representing prior information of anatomical shape, motion, and deformation to extrapolate intraoperative sparse data as well as surgeons' expertise and pathology to optimize interventions. Firstly, we present a review of methods for recovery of static anatomical structures by only using intraoperative data without any preoperative patient-specific information. Then, methods for recovery of intraoperative motion and deformation are reviewed by combining intraoperative sparse data with preoperative patient-specific stationary data, which is followed by a survey of articles which incorporated biomechanics. Furthermore, the articles are reviewed which addressed the used of statistical models for optimization of interventions. Finally, we conclude the survey by describing the future perspective.

  • Generalized Chat Noir is PSPACE-Complete

    Chuzo IWAMOTO  Yuta MUKAI  Yuichi SUMIDA  Kenichi MORITA  

     
    LETTER

      Vol:
    E96-D No:3
      Page(s):
    502-505

    We study the computational complexity of the following two-player game. The instance is a graph G = (V,E), an initial vertex s ∈ V, and a target set T ⊆ V. A “cat” is initially placed on s. Player 1 chooses a vertex in the graph and removes it and its incident edges from the graph. Player 2 moves the cat from the current vertex to one of the adjacent vertices. Players 1 and 2 alternate removing a vertex and moving the cat, respectively. The game continues until either the cat reaches a vertex of T or the cat cannot be moved. Player 1 wins if and only if the cat cannot be moved before it reaches a vertex of T. It is shown that deciding whether player 1 has a forced win on the game on G is PSPACE-complete.

  • Enhanced Photocurrent Properties of Dye/Au-Loaded TiO2 Films by Grating-Coupled Surface Plasmon Excitation

    Hathaithip NINSONTI  Weerasak CHOMKITICHAI  Akira BABA  Wiyong KANGWANSUPAMONKON  Sukon PHANICHPHANT  Kazunari SHINBO  Keizo KATO  Futao KANEKO  

     
    BRIEF PAPER

      Vol:
    E96-C No:3
      Page(s):
    385-388

    We report enhanced photocurrent properties of dye/Au-loaded titanium dioxide (TiO2) films on Au gratings. Au-loaded TiO2 nanopowders were first synthesized by a modified sol-gel method and then prepared by the impregnation method. We also fabricated dye-sensitized solar cells, which were composed of Au grating/Au-TiO2/TMPyP-SCC LbL (20 bilayers)/electrolyte/ITO substrates. Short-circuit photo-current measurements showed that Au-loaded TiO2 with grating-coupled surface plasmon excitation can enhance the short-circuit photocurrentof the fabricated cells.

  • A Method to Reduce Inter-ISP Transit Cost Caused by Overlay Routing Based on End-to-End Network Measurement

    Kazuhito MATSUDA  Go HASEGAWA  Satoshi KAMEI  Masayuki MURATA  

     
    PAPER-Information Network

      Vol:
    E96-D No:2
      Page(s):
    289-302

    Overlay routing is an application-level routing mechanism on overlay networks. Previous researches have revealed that the overlay routing can improve user-perceived performance. However, it may also generate traffic unintended by ISPs, incurring additional monetary cost. In addition, since ISPs and end users have their own objectives respectively regarding traffic routing, overlay routing must be operated considering both standpoints. In the present paper, we propose a method to reduce inter-ISP transit costs caused by overlay routing from the both standpoints of ISPs and end users. To determine the relationships among ASes, which are required for ISP cost-aware routing, we construct a method to estimate a transit cost of overlay-routed paths from end-to-end network performance values. Utilizing the metric, we propose a novel method that controls overlay routing from the both standpoints of ISPs and end users. Through extensive evaluations using measurement results from the actual network environments, we confirm that the advantage of the proposed method whereby we can reduce the transit cost in the overlay routing and can control the overlay routing according to the objectives of both ISPs and end users.

  • A Fully Automatic Player Detection Method Based on One-Class SVM

    Xuefeng BAI  Tiejun ZHANG  Chuanjun WANG  Ahmed A. ABD EL-LATIF  Xiamu NIU  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E96-D No:2
      Page(s):
    387-391

    Player detection is an important part in sports video analysis. Over the past few years, several learning based detection methods using various supervised two-class techniques have been presented. Although satisfactory results can be obtained, a lot of manual labor is needed to construct the training set. To overcome this drawback, this letter proposes a player detection method based on one-class SVM (OCSVM) using automatically generated training data. The proposed method is evaluated using several video clips captured from World Cup 2010, and experimental results show that our approach achieves a high detection rate while keeping the training set construction's cost low.

  • Bypass Extended Stack Processing for Anti-Thrashing Replacement in Shared Last Level Cache of Chip Multiprocessors

    Young-Sik EOM  Jong Wook KWAK  Seong-Tae JHANG  Chu-Shik JHON  

     
    LETTER-Computer System

      Vol:
    E96-D No:2
      Page(s):
    370-374

    Chip Multiprocessors (CMPs) allow different applications to share LLC (Last Level Cache). Since each application has different cache capacity demand, LLC capacity should be partitioned in accordance with the demands. Existing partitioning algorithms estimate the capacity demand of each core by stack processing considering the LRU (Least Recently Used) replacement policy only. However, anti-thrashing replacement algorithms like BIP (Binary Insertion Policy) and BIP-Bypass emerged to overcome the thrashing problem of LRU replacement policy in a working set greater than the available cache size. Since existing stack processing cannot estimate the capacity demand with anti-thrashing replacement policy, partitioning algorithms also cannot partition cache space with anti-thrashing replacement policy. In this letter, we prove that BIP replacement policy is not feasible to stack processing but BIP-bypass is. We modify stack processing to accommodate BIP-Bypass. In addition, we propose the pipelined hardware of modified stack processing. With this hardware, we can get the success function of the various capacities with anti-thrashing replacement policy and assess the cache capacity of shared cache adequate to each core in real time.

  • Texturization for Multi-Crystalline Silicon Solar Cells with Chlorine Trifluoride Gas and Acid Solution

    Takahiro SANDA  Yoji SAITO  

     
    BRIEF PAPER-Semiconductor Materials and Devices

      Vol:
    E96-C No:2
      Page(s):
    289-291

    We have investigated on a random-texturing process for multi-crystalline Si solar cells by plasmaless dry etching, with chlorine trifluoride (ClF3) gas treatments. The reflectance of textured surfaces was reduced to below 20% at a wavelength of 600 nm. In this study, we tried to improve the electrical characteristics by modifying the fabrication process. The substrate surfaces were dry etched by chlorine trifluoride gas and subsequently etched with an acid solution to form appropriate textured structures. The improved electrical characteristics were demonstrated.

  • A Design and Prototyping of In-Network Processing Platform to Enable Adaptive Network Services

    Masayoshi SHIMAMURA  Takeshi IKENAGA  Masato TSURU  

     
    PAPER

      Vol:
    E96-D No:2
      Page(s):
    238-248

    The explosive growth of the usage along with a greater diversification of communication technologies and applications imposes the Internet to manage further scalability and diversity, requiring more adaptive and flexible sharing schemes of network resources. Especially when a number of large-scale distributed applications concurrently share the resource, efficacy of comprehensive usage of network, computation, and storage resources is needed from the viewpoint of information processing performance. Therefore, a reconsideration of the coordination and partitioning of functions between networks (providers) and applications (users) has become a recent research topic. In this paper, we first address the need and discuss the feasibility of adaptive network services by introducing special processing nodes inside the network. Then, a design and an implementation of an advanced relay node platform are presented, by which we can easily prototype and test a variety of advanced in-network processing on Linux and off-the-shelf PCs. A key feature of the proposed platform is that integration between kernel and userland spaces enables to easily and quickly develop various advanced relay processing. Finally, on the top of the advanced relay node platform, we implement and test an adaptive packet compression scheme that we previously proposed. The experimental results show the feasibility of both the developed platform and the proposed adaptive packet compression.

  • Dynamic and Safe Path Planning Based on Support Vector Machine among Multi Moving Obstacles for Autonomous Vehicles

    Quoc Huy DO  Seiichi MITA  Hossein Tehrani Nik NEJAD  Long HAN  

     
    PAPER-Artificial Intelligence, Data Mining

      Vol:
    E96-D No:2
      Page(s):
    314-328

    We propose a practical local and global path-planning algorithm for an autonomous vehicle or a car-like robot in an unknown semi-structured (or unstructured) environment, where obstacles are detected online by the vehicle's sensors. The algorithm utilizes a probabilistic method based on particle filters to estimate the dynamic obstacles' locations, a support vector machine to provide the critical points and Bezier curves to smooth the generated path. The generated path safely travels through various static and moving obstacles and satisfies the vehicle's movement constraints. The algorithm is implemented and verified on simulation software. Simulation results demonstrate the effectiveness of the proposed method in complicated scenarios that posit the existence of multi moving objects.

  • Adaptive Insertion and Promotion Policies Based on Least Recently Used Replacement

    Wenbing JIN  Xuanya LI  Yanyong YU  Yongzhi WANG  

     
    LETTER-Computer System

      Vol:
    E96-D No:1
      Page(s):
    124-128

    To improve Last-Level Cache (LLC) management, numerous approaches have been proposed requiring additional hardware budget and increased overhead. A number of these approaches even change the organization of the existing cache design. In this letter, we propose Adaptive Insertion and Promotion (AIP) policies based on Least Recently Used (LRU) replacement. AIP dynamically inserts a missed line in the middle of the cache list and promotes a reused line several steps left, realizing the combination of LRU and LFU policies deliberately under a single unified scheme. As a result, it benefits workloads with high locality as well as with many frequently reused lines. Most importantly, AIP requires no additional hardware other than a typical LRU list, thus it can be easily integrated into the existing hardware with minimal changes. Other issues around LLC such as scans, thrashing and dead lines are all explored in our study. Experimental results on the gem5 simulator with SPEC CUP2006 benchmarks indicate that AIP outperforms LRU replacement policy by an average of 5.8% on the misses per thousand instructions metric.

  • Respiratory Motion and Correction Simulation Platform for Coronary MR Angiography

    Florencio Rusty PUNZALAN  Tetsuo SATO  Tomohisa OKADA  Shigehide KUHARA  Kaori TOGASHI  Kotaro MINATO  

     
    PAPER-Biological Engineering

      Vol:
    E96-D No:1
      Page(s):
    111-119

    This paper describes a simulation platform for use in the quantitative assessment of different respiratory motion correction techniques in Coronary MR angiography (CMRA). The simulator incorporates acquisition of motion parameters from heart motion tracking and applies it to a deformable heart model. To simulate respiratory motion, a high-resolution 3-D coronary heart reference image is deformed using the estimated linear transformation from a series of volunteer coronal scout scans. The deformed and motion-affected 3-D coronary images are used to generate segmented k-space data to represent MR data acquisition affected by respiratory motion. The acquired k-space data are then corrected using different respiratory motion correction methods and converted back to image data. The resulting images are quantitatively compared with each other using image-quality measures. Simulation experiment results are validated by acquiring CMRA scans using the correction methods used in the simulation.

  • Effect of Environmental Factors on System Capacity and Coverage of Femtocell Networks

    Hoon KIM  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E96-B No:1
      Page(s):
    201-207

    Recently much attention is being devoted to a femtocell's potential for improving indoor cellular coverage with the provision of high data rate services in a wireless environment. Femtocells are usually deployed in homes and buildings and overlay existing macrocells, or microcells which cover wider service areas. In such an overlaid network structure, one of the important issues in network planning is the analysis of system capacity achievable by femtocells, which could be significantly affected by indoor radio propagation properties. This paper addresses a typical environmental scenario where a detailed indoor radio propagation model can be adopted. Moreover, a performance evaluation of embedded femteocell networks reflecting various environmental scenarios and factors is provided by the metrics of outage probability, dynamic range of spectral efficiency, and required separation distances for various wall structures, distance, and the number of walls between the home femtocell and the user. Our computer simulation and numerical analysis indicate an outage probability of 1%∼58%, dynamic range of spectral varies from around 2.2 to 7, while the required separation from the macrocell station is 25 m ∼ 327 m. This information could be useful for femtocell network planning.

  • Scattering of a Scalar Plane Wave by a Sinusoidal Edge

    Tomoya IZUTSU  Akira KOMIYAMA  

     
    BRIEF PAPER-Scattering and Diffraction

      Vol:
    E96-C No:1
      Page(s):
    55-59

    We deal with the scattering of a scalar plane wave by a half plane with a sinusoidally deformed edge from a straight edge by a physical optics approximation. The normal incidence of a plane wave to an edge is assumed. A contribution of an edge to the field integral is asymptotically evaluated and the basic properties of the scattering caused by the edge deformation is clarified. The scattering pattern has peaks at specific scattering angles, which agree with diffraction angles calculated by the well-known grating formula for normal incidence. Some numerical examples are shown and it is shown that the results are in good agreement with the results obtained by the GTD method for low angle incidence.

381-400hit(1376hit)