• Title/Summary/Keyword: Parallel Calculation

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Resource management for moldable parallel tasks supporting slot time in the Cloud

  • Li, Jianmin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.9
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    • pp.4349-4371
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    • 2019
  • Moldable parallel tasks are widely used in different areas, such as weather forecast, biocomputing, mechanical calculation, and so on. Considering the deadline and the speedup, scheduling moldable parallel tasks becomes a difficulty. Past work majorly focuses on the LA (List Algorithms) or OMA (Optimizing the Middle Algorithms). Different from prior work, our work normalizes execution time and makes all tasks have the same scope in normalized execution time: [0,1], and then according to the normalized execution time, a method is used to search for the reference execution time without considering the deadline of tasks. According to the reference execution time, we get an initial scheduling result based on AFCFS (Adaptive First Comes First Served) policy. Finally, a heuristic approach is used to improve the performance of the initial scheduling result. We call our method HSRET (a Heuristic Scheduling method based on Reference Execution Time). Comparisons to other methods show that HSRET has good performance in AWT (Average Waiting Time), AET (Average Execution Time), and PUT (Percentages of Unfinished Tasks).

The Parallel Operation of Single Phase PWM Rectifier using IGBT (IGBT를 이용한 단산 PWM정류기 병렬운전)

  • 이현원;장성영;김연준;이광주;김남해
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.122-125
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    • 1999
  • The AC-to-DC single-phase PWM rectifier for traction applications using high power semiconductor, IGCT is made and tested. Parallel operation of two PWM converter is adopted for increasing capacity of converters. For reducing harmonics, the harmonic content is eliminated by the phase shift between two converters switching phase. The output voltage control is achieved by interns calculation without detecting the input current. The part of PLL used for controlling power factor is simply implemented by software.

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Fault Location Algorithm for Parallel Transmission Line with a Teed Circuit (1회선 분기점을 갖는 병행 2회선 송전선로의 고장점 표정 알고리즘)

  • Kwon, Tae-Won;Kang, Sang-Hee;Choi, Myeon-Song;Lee, Seung-Jae
    • Proceedings of the KIEE Conference
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    • 1999.11b
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    • pp.116-118
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    • 1999
  • A fault location algorithm that is suitable for parallel transmission line which contains a teed circuit is presented. The method uses only the local end voltage and current signals. Zero sequence currents of other lines are calculated by distribution factors, and distance equations are solved by recursive calculation.

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A PLANE-PARALLEL MODEL OF THE DIFFUSE GALACTIC LIGHT (확산 은하 복사광에 대한 평면 평행 모델)

  • Seon, Kwang-Il
    • Publications of The Korean Astronomical Society
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    • v.24 no.1
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    • pp.1-8
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    • 2009
  • A plane-parallel model of the diffuse Galactic light (DGL) is calculated assuming exponential disks of interstellar dust and OB stars, by solving exactly the radiative transfer equation using an iterative method. We perform a radiative transfer calculation for a model with generally accepted scale heights of stellar and dust distribution and compare the results with those of van de Hulst & de Jong for a constant slab model. We also find that the intensity extrapolated to zero dust optical depth has a negative value, against to the usual expectation.

Calculating Mutual Impedance between Power-Line and Communication-Line with Earth Return Current (대지귀로 전류에 의한 전력선과 통신선의 상호임피던스 해석)

  • Lim, Yong-Hun;Hyun, Duck-Hwa
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.269-271
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    • 2003
  • A method for calculation of mutual inductance from the parallel power-line and earth conduct to communication-line is studied in the paper. The solution for the electromagnetic field produced by an overhead power-line is derived using Maxwell's equations and treating the as a boundary value problem. Total mutual inductance from direct current and image current to communication-line is used Carson's formula for infinitely long parallel conductors.

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디지털 필터 전용처리기의 설계와 구성에 관한 연구

  • 남상엽;박인정;이태원
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1984.04a
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    • pp.29-32
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    • 1984
  • A microprocessor for the dedicated purpose of digital filtering has been designed and constructed. A microsequencer to control the flowing of data is designed with the concept of a hardware compiler of AHPI, statements. In order to save the processing time, this system utilizes parallel data calculation method instead of the one proposed by Peled and Liu which depended on serial calculation method. The flexible program control technique has been applied to the implementation of the sepcialprocessor for the digital signal processing.

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Parallel Nonlinear Analysis of Prestressed Concrete Frame on Cluster System (클러스터 시스템에서 프리스트레스트 콘크리트 프레임의 병렬 비선형해석)

  • 이재석;최규천
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.14 no.3
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    • pp.287-298
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    • 2001
  • Analysis of nonlinear behavior of prestressed concrete frame structures on PC is a time-consuming computing job if the problem size increase to a certain degree. Cluster system has emerged as one of promising computing environments due to its good extendibility, portability, and cost-effectiveness, comparing it with high-end work-stations or servers. In this paper, a parallel nonlinear analysis procedure of prestressed concrete frame structure is presented using cluster computing. Cluster system is configured with readily available pentium III class PCs under Win98 or Linux and fast ethernet. Parallel computing algorithms on element-wise processing parts including the calculation of stiffness matrix, element stresses and determination of material states, check of material failure and calculation of unbalanced loads are developed using MPL. Validity of the method is discussed through typical numerical examples. For the case of 4 node system, maximum speedup is 3.15 and 3.74 for Win98 and Linux, respectively. Important issues for the efficient use of cluster computing system based un PCs and ethernet are addressed.

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Parallel Computing Strategies for High-Speed Impact into Ceramic/Metal Plates (세라믹/금속판재의 고속충돌 파괴 유한요소 병렬 해석기법)

  • Moon, Ji-Joong;Kim, Seung-Jo;Lee, Min-Hyung
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.6
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    • pp.527-532
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    • 2009
  • In this paper simulations for the impact into ceramics and/or metal materials have been discussed. To model discrete nature for fracture and damage of brittle materials, we implemented cohesive-law fracture model with a node separation algorithm for the tensile failure and Mohr-Coulomb model for the compressive loading. The drawback of this scheme is that it requires a heavy computational time. This is because new nodes are generated continuously whenever a new crack surface is created. In order to reduce the amount of calculation, parallelization with MPI library has been implemented. For the high-speed impact problems, the mesh configuration and contact calculation changes continuously as time step advances and it causes unbalance of computational load of each processor. Dynamic load balancing technique which re-allocates the loading dynamically is used to achieve good parallel performance. Some impact problems have been simulated and the parallel performance and accuracy of the solutions are discussed.

Performance Characterization of Tachyon Supercomputer using Hybrid Multi-zone NAS Parallel Benchmarks (하이브리드 병렬 프로그램을 이용한 타키온 슈퍼컴퓨터의 성능)

  • Park, Nam-Kyu;Jeong, Yoon-Su;Yi, Hong-Suk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.1
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    • pp.138-144
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    • 2010
  • Tachyon primary system which introduces recently is a high performance supercomputer that composed with AMD Barcelona nodes. In this paper, we will verify the performance and parallel scalability of TachyonIn by using multi-zone NAS Parallel Benchmark(NPB) which is one of a program with hybrid parallel method. To test performance of hybrid parallel execution, B and C classes of BT-MZ in NPB version 3.3 were used. And the parallel scalability test has finished with Tachyon's 1024 processes. It is the first time in Korea to get a result of hybrid parallel computing calculation using more than 1024 processes. Hybrid parallel method in high performance computing system with multi-core technology like Tachyon describes that it can be very efficient and useful parallel performance benchmarks.

Vergence control of parallel stereoscopic camera using the binocular disparity information (시차정보를 이용한 수평이동방식 입체영상 카메라의 주시각제어)

  • Kwon, Ki-Chul;Kim, Nam
    • Korean Journal of Optics and Photonics
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    • v.15 no.2
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    • pp.123-129
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    • 2004
  • This paper concerns auto vergence control of a parallel stereoscopic camera through geometrical analysis. In the construction of a parallel stereoscopic camera, we experimentally demonstrated linear relationship between the key object distance and the amount of vergence control. And we proposed a vergence control system for the stereoscopic camera using binocular disparity information. For the real-time calculation of disparity information, the Hybrid Cepstral filter algorithm, with input data acquired from the vertical projection data and from the down sampling data from the source images, was proposed for precision and high speed processing. With the disparity information algorithm and the vergence control of the parallel stereoscopic camera system, the stereoscopic images become more like those of the human eye.