• Title/Summary/Keyword: parallel machines

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Rotor Loss Analysis of Permanent Magnet High-Speed Machine According to Magnetization Pattern

  • Cho, Han-Wook;Jang, Seok-Myeong;Lee, Sung-Ho;Yang, Hyun-Sup;Jeong, Yeon-Ho
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.4B no.3
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    • pp.103-107
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    • 2004
  • Recently, greater attention has been paid to the high-speed generator for its many merits, such as ease of installation, high efficiency and high power density. However, due to their high fundamental frequency, careful consideration needs to be given to both electromagnetic and mechanical design issues. This paper deals with the comparison of two types of permanent magnet high-speed machines. Specifically, the effect of the permanent magnet magnetization pattern on the rotor losses is investigated. On the basis of analytical field analysis and the 2-D finite element method, this paper predicts the flux harmonics and rotor losses under the no-load condition. It is shown that the Halbach magnetization is superior to parallel magnetization in terms of producing rotor losses.

Development of Automatic Rearing System of Silkworm

  • Osamu Ninagi
    • Proceedings of the Korean Society of Sericultural Science Conference
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    • 1997.06a
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    • pp.103-117
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    • 1997
  • Decrease in the cocoon production of Japan is drastic because of low price of cocoon, scarcity of successors and so on. To tide over the difficulty, the automation system in the sericulture was discussed and some trials have been conducted by the Ministry of Agriculture, Forestry and Fisheries of Japan. The attempts are based on a low cost artificial diet which does not rely on mulberry leaves. Automatic machines developed until now are a rearing machine constituted with repeated belt conveyor, an reformation type of former rearing machine "Bombyx" and a mounting machine. Running parallel with them, utilization of 20-hydroxyecdysone extracted from a plant to the mounting was also studied to use their machines efficiently in the fields. In conclusion, 10 tons of law cocoon will come to be produced by two persons labor. At present, an automatic rearing system on low cost artificial diet has been developing for the future sericulture.

A Reconfigurable Load and Performance Balancing Scheme for Parallel Loops in a Clustered Computing Environment (클러스터 컴퓨팅 환경에서 병렬루프 처리를 위한 재구성 가능한 부하 및 성능 균형 방법)

  • 김태형
    • Journal of KIISE:Computing Practices and Letters
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    • v.10 no.1
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    • pp.49-56
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    • 2004
  • Load imbalance is a serious impediment to achieving good performance in parallel processing. Global load balancing schemes cannot adequately manage to balance parallel tasks generated from a single application. Dynamic loop scheduling methods are known to be useful in balancing parallel loops on shared-memory multiprocessor machines. However, their centralized nature causes a bottleneck for the relatively small number of processors in a network of workstations because of order-of-magniture differences in communication overheads. Moreover, improvements of basis loops scheduling methods have not effectively dealt with irregularly distributed workloads in parallel loops, which commonly occur in applications for a network of workstation. In this paper, we present a new reconfigurable and decentralized balancing method for parallel loops on a network of workstations. Since our method supplements performance balancing with those tranditional load balancing methods, it minimizes the overall execution time.

A Hardware-Based String Matching Using State Transition Compression for Deep Packet Inspection

  • Kim, HyunJin;Lee, Seung-Woo
    • ETRI Journal
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    • v.35 no.1
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    • pp.154-157
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    • 2013
  • This letter proposes a memory-based parallel string matching engine using the compressed state transitions. In the finite-state machines of each string matcher, the pointers for representing the existence of state transitions are compressed. In addition, the bit fields for storing state transitions can be shared. Therefore, the total memory requirement can be minimized by reducing the memory size for storing state transitions.

FUZZY HYPERCUBES: A New Inference Machines

  • Kang, Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.2 no.2
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    • pp.34-41
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    • 1992
  • A robust and reliable learning and reasoning mechanism is addressed based upon fuzzy set theory and fuzzy associative memories. The mechanism stores a priori an initial knowledge base via approximate learning and utilizes this information for decision-making systems via fuzzy inferencing. We called this fuzzy computer architecture a 'fuzzy hypercube' processing all the rules in one clock period in parallel. Fuzzy hypercubes can be applied to control of a class of complex and highly nonlinear systems which suffer from vagueness uncertainty. Moreover, evidential aspects of a fuzzy hypercube are treated to assess the degree of certainty or reliability together with parameter sensitivity.

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Control Hierarchy Analysis of Haenam-Cheju HVDC system (해남-제주 HVDC 계통의 제어 계층 구조 분석)

  • Kwak, Joo-Sik
    • Proceedings of the KIEE Conference
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    • 1999.07c
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    • pp.1327-1330
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    • 1999
  • In this paper control hierarchy of Haenam-Cheju HVDC link are analyzed and their functional specifications are summarized related to their level. The control functions for the submarine DC transmission are implemented by software programs on 16-bit parallel processor-based machines which are composed of subunits hierarchically linked each other

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A Parallel Algorithm of Davidson Method for Eigenproblems (고유치 솔버 Davidson Method 의 병렬화)

  • Kim, Hyoung-Joong;Zhu, Yu
    • Proceedings of the KIEE Conference
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    • 1997.07a
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    • pp.12-14
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    • 1997
  • The analysis of eigenvalue and eigenvector is a crucial procedure for many electromagnetic computation problems. However, eigenpair computation is timing-consuming task. Thus, its parallelization is required for designing large-scale and precision three-dimensional electromagnetic machines. In this paper, the Davidson method is parallelized on a cluster of workstations. Performance of the parallelization scheme is reported. This scheme is applied to a ridged waveguide design problem.

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A Study on Neural Network for Path Searching in Switching Network (스윗칭회로의 경로설정을 위한 신경 회로망 연구)

  • Park, Seung-Kyu;Lee, Noh-Sung;Woo, Kwang-Bang
    • Proceedings of the KIEE Conference
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    • 1990.11a
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    • pp.432-435
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    • 1990
  • Neural networks are a class of systems that have many simple processors (neurons) which are highly interconnected. The function of each neuron is simple, and the behavior is determined predominately by the set of interconnections. Thus, a neural network is a special form of parallel computer. Although major impetus for using neural networks is that they may be able to "learn" the solution to the problem that they are to solve, we argue that another, perhaps even stronger, impetus is that they provide a framework for designing massively parallel machines. The highly interconnected architecture of switching networks suggests similarities to neural networks. Here, we present switching applications in which neural networks can solve the problems efficiently. We also show that a computational advantage can be gained by using nonuniform time delays in the network.

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An Experimental Study on the Performance Evaluation of a Small-Sized Centrifugal Compressor (소형 원심압축기의 성능평가에 대한 실험적 연구)

  • Cho, Sung-Kook;Kang, Shin-Hyoung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.8
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    • pp.1052-1063
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    • 1998
  • The performance database of small-sized centrifugal compressors is needed for the design of high performance machines and also for the verification of design tools and analysis software. An impeller is designed, manufactured and tested. The effects of several parameters on the evaluation of performance are investigated and the performance test of parallel diffuser is also carried out. The proper estimation of static pressure, total temperature and blockage at the impeller exit is important for performance evaluation. 4 method in cooperation with 3-D calculation is suggested. The measured performances are in a good agreement with the predicted results. However, there are some discrepancies in efficiency.

A Lagrangian Relaxation Method for Parallel Machine Scheduling with Resource Constraints

  • Kim, Dae-Cheol
    • IE interfaces
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    • v.11 no.3
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    • pp.65-75
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    • 1998
  • This research considers the problem of scheduling jobs on parallel machines with non-common due dates and additional resource constraints. The objective is to minimize the total absolute deviation of job completion times about the due dates. Job processing times are assumed to be the same. This problem is motivated by restrictions that occur in the handling and processing of jobs in certain phases of semiconductor manufacturing and other production systems. We examine two problems. For the first of these, the number of different types of additional: resources and resource requirements per job are arbitrary. The problem is formulated as a zero-one integer linear programming and the Lagrangian relaxation approach is used. For the second case, there exists one single type of additional resource and the resource requirements per job are zero or one. We show how to formulate the problem as an assignment problem.

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