• Title, Summary, Keyword: Hybrid Parallel Programming

Search Result 23, Processing Time 0.036 seconds

Performance Enhancement of Parallel Prime Sieving with Hybrid Programming and Pipeline Scheduling (혼합형 병렬처리 및 파이프라이닝을 활용한 소수 연산 알고리즘)

  • Ryu, Seung-yo;Kim, Dongseung
    • KIPS Transactions on Computer and Communication Systems
    • /
    • v.4 no.10
    • /
    • pp.337-342
    • /
    • 2015
  • We develop a new parallelization method for Sieve of Eratosthenes algorithm, which enhances both computation speed and energy efficiency. A pipeline scheduling is included for better load balancing after proper workload partitioning. They run on multicore CPUs with hybrid parallel programming model which uses both message passing and multithreading computation. Experimental results performed on both small scale clusters and a PC with a mobile processor show significant improvement in execution time and energy consumptions.

Comparison of the Fuel Economy of Series and Parallel Hybrid Bus System Using Dynamic Programming (동적 계획법을 이용한 직렬형 및 병렬형 하이브리드 버스 시스템 연비 비교)

  • Jeong, Jongryeol;Lee, Daeheung;Shin, Changwoo;Jeong, Daebong;Min, Kyoungdoug;Cha, Suk Won;Park, Yeong-Il
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.21 no.1
    • /
    • pp.92-98
    • /
    • 2013
  • There are lots of studies about hybrid electric vehicles (HEVs) because of the global warming and energy problems. Series and parallel HEVs are the common types of many developing hybrid vehicle types. Series HEV uses engine only as the generator for the battery but parallel HEV utilizes engine for driving and generating of the vehicle. In this paper, backward simulations based on dynamic programming were conducted for the fuel economy analysis of two different types of hybrid transit buses depending on driving cycles. It is shown that there is a relation between the type of HEV and the characteristics of driving cycles. Regarding the aggressiveness, the series hybrid bus is more efficient than the parallel system on highly aggressive driving cycle. On the other hand, the parallel hybrid bus is more efficient than the series system on low aggressive driving cycle. Based on this results of the paper, it is expected to choose more efficient type of the hybrid buses according to the driving cycle.

Comparative and Combined Performance Studies of OpenMP and MPI Codes (OpenMP와 MPI 코드의 상대적, 혼합적 성능 고찰)

  • Lee Myung-Ho
    • The KIPS Transactions:PartA
    • /
    • v.13A no.2
    • /
    • pp.157-162
    • /
    • 2006
  • Recent High Performance Computing (HPC) platforms can be classified as Shared-Memory Multiprocessors (SMP), Massively Parallel Processors (MPP), and Clusters of computing nodes. These platforms are deployed in many scientific and engineering applications which require very high demand on computing power. In order to realize an optimal performance for these applications, it is crucial to find and use the suitable computing platforms and programming paradigms. In this paper, we use SPEC HPC 2002 benchmark suite developed in various parallel programming models (MPI, OpenMP, and hybrid of MPI/OpenMP) to find an optimal computing environments and programming paradigms for them through their performance analyses.

OPTIMAL TORQUE MANAGEMENT STRATEGY FOR A PARALLEL HYDRAULIC HYBRID VEHICLE

  • Sun, H.;Jiang, J.H.;Wang, X.
    • International Journal of Automotive Technology
    • /
    • v.8 no.6
    • /
    • pp.791-798
    • /
    • 2007
  • The hydraulic hybrid vehicle(HHV) is an application of hydrostatic transmission technology to improve vehicle fuel economy and emissions. A relatively lower energy density of hydraulic accumulator and complicated coordinating operations between two power sources require a special energy management strategy to maximize the fuel saving potential. This paper presents a new type of configuration for parallel HHV to minimize the disadvantages of the hydraulic accumulator, as well as a methodology for developing an energy management strategy tailored specially for PHHV. Based on an analysis of the optimal energy distribution between two power sources over a representative urban driving cycle with a Dynamic Programming(DP) algorithm, a fuzzy-based optimal torque management strategy is designed and developed to control the torque distribution. Simulation results demonstrates that the optimal torque management strategy maximizes the advantages of this hybrid type of configuration, and the high power density characteristics of hydraulic technology effectively improve the robustness of the energy management strategy and fuel economy of the PHHV.

A Hybrid Parallel Genetic Algorithm for Reliability Optimal Design of a Series System (직렬시스템의 신뢰도 최적 설계를 위한 Hybrid 병렬 유전자 알고리즘 해법)

  • Kim, Ki-Tae;Jeon, Geon-Wook
    • Journal of the Society of Korea Industrial and Systems Engineering
    • /
    • v.33 no.2
    • /
    • pp.48-55
    • /
    • 2010
  • Reliability has been considered as a one of the major design measures in various industrial and military systems. The main objective is to suggest a mathematical programming model and a hybrid parallel genetic algorithm(HPGA) for the problem that determines the optimal component reliability to maximize the system reliability under cost constraint in this study. Reliability optimization problem has been known as a NP-hard problem and normally formulated as a mixed binary integer programming model. Component structure, reliability, and cost were computed by using HPGA and compared with the results of existing meta-heuristic such as Ant Colony Optimization(ACO), Simulated Annealing(SA), Tabu Search(TS) and Reoptimization Procedure. The global optimal solutions of each problem are obtained by using CPLEX 11.1. The results of suggested algorithm give the same or better solutions than existing algorithms, because the suggested algorithm could paratactically evolved by operating several sub-populations and improving solution through swap and 2-opt processes.

Performance Analysis of the Parallel CUPID Code for Various Parallel Programming Models in Symmetric Multi-Processing System (Symmetric Multi-Processing 시스템에서 다양한 병렬 기법 모델을 적용한 병렬 CUPID 코드의 성능분석)

  • Jeon, Byoung Jin;Lee, Jae Ryong;Yoon, Han Young;Choi, Hyoung Gwon
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.38 no.1
    • /
    • pp.71-79
    • /
    • 2014
  • A parallelization of the bi-conjugate gradient solver for the pressure equation of the CUPID (component unstructured program for interfacial dynamics) code, which was developed for analyzing the components of a pressurized water-cooled reactor, was studied in a symmetric multi-processing system. The parallel performance was investigated for three typical parallel programming models (MPI, OpenMP, Hybrid) by solving incompressible backward-facing step flow at various grid resolutions. It was confirmed that parallel performance was low when problem size was small or the memory requirement for each thread was considerably higher than the cache memory. Furthermore, it was shown that MPI was better than OpenMP regardless of the problem size, and Hybrid was the best when the number of threads was relatively small.

Comparison of Message Passing Interface and Hybrid Programming Models to Solve Pressure Equation in Distributed Memory System (분산 메모리 시스템에서 압력방정식의 해법을 위한 MPI와 Hybrid 병렬 기법의 비교)

  • Jeon, Byoung Jin;Choi, Hyoung Gwon
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.39 no.2
    • /
    • pp.191-197
    • /
    • 2015
  • The message passing interface (MPI) and hybrid programming models for the parallel computation of a pressure equation were compared in a distributed memory system. Both models were based on domain decomposition, and two numbers of the sub-domain were selected by considering the efficiency of the hybrid model. The parallel performances for various problem sizes were measured using up to 96 threads. It was found that in addition to the cache-memory size, the overhead of the MPI communication/OpenMP directives affected the parallel performance. For small problems, the parallel performance was low because the percentage of the overhead of the MPI communication/OpenMP directives increased as the number of threads increased, and MPI was better than the hybrid model because it had a smaller communication overhead. For large problems, the parallel performance was high because, in addition to the cache effect, the percentage of the communication overhead was relatively low compared to that for small problems, and the hybrid model was better than MPI because the communication overhead of MPI was more dominant than that of the OpenMP directives in the hybrid model.

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
    • /
    • v.14 no.1
    • /
    • pp.138-144
    • /
    • 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.

Analysis of Work Load for Developing the Control Strategy of Hybrid Agricultural Tractor (하이브리드 농업용 트랙터의 제어 전략 개발을 위한 작업 부하 분석)

  • Kim, Jinseong;Park, Yeongil
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.23 no.2
    • /
    • pp.239-245
    • /
    • 2015
  • In order to control the hybrid power system efficiently, the knowledge for the required load of the system is important. The agricultural tractor performs various farm works such as plow, rotary, and baler. When it performs rotary tillage and baler operation, the generated work load is analyzed. To analyze trend of work load, moving average technique is applied to the measurement data. Optimal control inputs for the two works are obtained from simulation using the dynamic programming. The novel fundamental control strategy for parallel hybrid tractor called Max. SOC is proposed.

A Hybrid Method for Improvement of Evolutionary Computation (진화 연산의 성능 개선을 위한 하이브리드 방법)

  • Chung, Jin-Ki;Oh, Se-Young
    • Journal of Korean Institute of Intelligent Systems
    • /
    • v.12 no.4
    • /
    • pp.317-322
    • /
    • 2002
  • The major operations of Evolutionary Computation include crossover, mutation, competition and selection. Although selection does not create new individuals like crossover or mutation, a poor selection mechanism may lead to problems such as taking a long time to reach an optimal solution or even not finding it at all. In view of this, this paper proposes a hybrid Evolutionary Programming (EP) algorithm that exhibits a strong capability to move toward the global optimum even when stuck at a local minimum using a synergistic combination of the following three basic ideas. First, a "local selection" technique is used in conjunction with the normal tournament selection to help escape from a local minimum. Second, the mutation step has been improved with respect to the Fast Evolutionary Programming technique previously developed in our research group. Finally, the crossover and mutation operations of the Genetic Algorithm have been added as a parallel independent branch of the search operation of an EP to enhance search diversity.