• Proceedings of the Korean Society of Computer Information Conference
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• 2019.07a
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• pp.257-258
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• 2019

본 논문에서는 "프로세서 중심 컴퓨터 구조"에서 개발된 MPI 병렬 프로그램을 수정하지 않고 "메모리 중심 컴퓨터 구조"에서 더 효율적으로 수행시키는 기술을 제안한다. 본 연구에서 제안하는 기술은 메모리 중심 컴퓨터 구조가 가지는 "빠른 대용량 공유 메모리" 특징을 이용하여 MPI 표준 라이브러리가 수행하는 네트워크 통신을 통한 느린 데이터 전달을 공유 메모리를 통한 빠른 데이터 전달로 대체하여 효율성을 얻는다. 본 연구에서 제안한 기술은 도커 가상화 기술을 사용한 분산 시스템 환경에서 MC-MPI-LIB 라이브러리 및 MC-MPI-SIM 시뮬레이터로 구현되었으며 다수의 MPI 병렬 프로그램으로 시험 수행하여 효율성이 있음을 보였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.1B
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• pp.59-66
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• 2012

The use of MPSoC has been increasing because of a rise of use of mobile devices and complex applications. For improving the performance of MPSoC, number of processor has been increasing. Standard MPI is used for efficiently sending data in distributed memory architecture that has advantage in multi processor. Standard In this paper, we propose a scalable distributed memory system with a low cost hardware message passing interface(MPI). The proposed architecture improves transfer rate with buffered send for small size packet. Three queues, Ready Queue, Request Queue, and Reservation Queue, work as previous architecture, and two queues, Small Ready Queue and Small Request Queue, are added to send small size packet. When the critical point is set 8 bytes, the proposed architecture takes more than 2 times the performance improvement in the data that below the critical point.

• The KIPS Transactions:PartA
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• v.12A no.3 s.93
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• pp.253-262
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• 2005

Local accounting system used by UNIX-like operating system provides the accounting information of processes that are in single host. But it is impossible for this local accounting system to record the total resource consumption data of all processes for doing the same job simultaneously. In this paper, we implement accounting system to measure and manage resource usage for MPI(Message Passing Interface) job in the clustering environment. We designed and implemented the accounting system which measure resource usage of each process runs on a cluster node and record the interconnection information of the entire set of processes across network. Also we implemented accounting system which collect the resource usage data of process in the local accounting system and generate the job-level accounting information. Finally, to evaluate the resource consumption data measured by this accounting system we compare with the data collected by local scheduler that widely used in large scale clustering environment.

• Electronics and Telecommunications Trends
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• v.37 no.6
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• pp.43-53
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• 2022

Message Passing Interface (MPI) collective communication has been applied to various science and engineering area such as physics, chemistry, biology, and astronomy. The parallel computing performance of the data-intensive workload in the above research fields depends on the collective communication performance. To overcome this limitation, MPI collective communication technology has been extensively researched over the last several decades to improve communication performance. In this paper, we provide a comprehensive survey of the state-of-the-art research performed on the MPI collective communication and examine the trends of recently developed technologies. We also discuss future research directions for providing high performance and scalability to large-scale MPI applications.

• 한국전산유체공학회:학술대회논문집
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• 2006.05a
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• pp.408-411
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• 2006

• Journal of computational fluids engineering
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• v.13 no.1
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• pp.35-40
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• 2008

Generally flight vehicles have many cavities such as wheel wells, bomb bays and windows on their external surfaces and the flow around these cavities makes separation, vortex, shock and expansion waves, reattachment and other complex flow phenomenon. The flow around the cavity makes abnormal and three-dimensional noise and vibration even thought the aspect ratio (L/D) is small. The cavity giving large effects to the flow might make large noise, cause structural damage or breakage, harm the aerodynamic performance and stability, or damage the sensitive devices. In this study, numerical analysis was performed for cavity flows by the unsteady compressible three dimensional Reynolds-Averaged Navier-Stokes (RANS) equations with Wilcox's $\kappa-\omega$ turbulence model. The MPI(Message Passing Interface) parallelized code was used for calculations by PC-cluster. The cavity has the aspect ratios of 2.5, 3.5 and 4.5 with the W/D ratio of 2 for three-dimensional cavities. The Sound Pressure Level (SPL) analysis was done with FFT to check the dominant frequency of the cavity flow. The dominant frequencies were analyzed and compared with the results of Rossiter's formula and Ahuja& Mendoza's experimental datum.

• The KIPS Transactions:PartA
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• v.12A no.5 s.95
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• pp.421-426
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• 2005

In a large scale parallel computation, some processor or communication link failure results in a waste of huge amount of CPU hours. However, MPI in its current specification gives the user no possibility to handle such a problem. In this paper, we propose an application-level fault tolerant linear system solver by using an MPMD-type asynchronous iteration, purely on the basis of the MPI standard without using any non-standard fault-tolerant MPI library.

• Journal of computational fluids engineering
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• v.6 no.1
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• pp.31-39
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• 2001

연소실 안으로 분출되는 스월 유동의 vortex breakdown mechanism에 대한 연구를 하였다. 3차원 유한 체적기법과 Runge-Kutta 시간 적분법이 적용되었으며, 난류모델은 dynamic large eddy simulation (DLES)이 적용되었다. 계산 시간의 효율성과 기억용량을 효과적으로 사용하기 위하여 message passing interface (MPI) 병렬계산 기법이 적용되었다. 스월 난류 유동에 있어서 vortex breakdown 거동을 가시적으로 표착 하였는데, 이는 스월 유동에 의한 난류 응력 증대, 난류 생성/소산율 증대 및 혼합율 증대에 대한 실험적 근거를 뒷받침하는 매우 중요한 결과이다. 또한 평균 속도와 난류 운동에너지에 대한 계산 결과도 실험 결과와 비교하였다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.56-59
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• 2010

포화된 다공질 매체의 수치해석은 일반적으로 혼합유한요소방법(Mixed Finite Element Method)이 쓰인다. 이 혼합유한요소 방법은 고체변형과 유체의 이동을 동시에 고려하게 되는데 고체의 변형이 거의 없이 유체만 이동할 경우나 고체와 유체의 변형이 없이 간극수압만 존재할 경우에는 요소잠김현상(Element Locking)이 발생하여 혼합유한요소방법으로 해석하기에는 수치적으로 불안정해 진다. 본 논문에서는 이러한 수치적 불안정성을 해결한 스태거드 방법(Park and Tak 2010)을 소개하고 수치적 효율성을 위해 MPI(Message-Passing Interface) 라이브러리를 이용한 병렬해석 기법이 적용된다.

• Journal of the Korea Society of Computer and Information
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• v.11 no.6 s.44
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• pp.69-78
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• 2006

In the field of the bioinformatics, it plays an important role in predicting functional information or structure information to search similar sequence in biological DB. Biolrgical sequences have been increased dramatically since Human Genome Project. At this point, because the searching speed for the similar sequence is highly regarded as the important factor for predicting function or structure, the SMP(Sysmmetric Multi-Processors) computer or cluster is being used in order to improve the performance of searching time. As the method to improve the searching time of BLAST(Basic Local Alighment Search Tool) being used for the similarity sequence search, We suggest the nBLAST algorithm performing on the cluster environment in this paper. As the nBLAST uses the MPI(Message Passing Interface), the parallel library without modifying the existing BLAST source code, to distribute the query to each node and make it performed in parallel, it is possible to easily make BLAST parallel without complicated procedures such as the configuration. In addition, with the experiment performing the nBLAST in the 28 nodes of LINUX cluster, the enhanced performance according to the increase in the number of the nodes has been confirmed.