• Proceedings of the KSME Conference
• /
• 대한기계학회 2000년도 춘계학술대회논문집B
• /
• pp.586-592
• /
• 2000

터보머신 태부에 존재하는 정익 - 동익의 상호작용 유동현상을 수치모사 하는 코드를 병렬화 하였다 정익 - 동익의 상호작용을 해석하는 데에 편리하도륵 Multi-Block Grid System을 도입하여 계산영역을 형성하였고, 동익의 움직임으로 인해 발생하는 Sliding Interface부분은 Patched 알고리즘을 적용하여 해석하였다. 정익과 동익의 수를 1대 1로 단순화시켜 수치모사한 결과와 정익과 동익의 수를 실제 조건과 더 비슷하게 설정한 3대 4의 비율로 맞추어 수치모사한 결과를 비교하였다. 또한, 병렬컴퓨팅으로 인해 단축된 계산시간을 다른 연구에서의 계산시간들과 서로 비교하였다. 2차원 비정상 압축성 Navier-Stokes 방정식이 이용되었고, 난류모델링에는 K-w SST 모델링이 적응되었다. Roe의 FDS 기법을 사용하여 플럭스를 계산하였고, MUSCL 기법을 적용하여 3차의 공간정확도를 갖도록 하였다. 시간적분에는 이보성의 DP-SGS를 사용하였다. 해석결과의 분석에는 Time-averaged pressure distribution과 Pressure amplitude distribution 데이터를 사용했다.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• 제20권3호
• /
• pp.281-286
• /
• 2007

An engineering design problem involving Multi-Disciplinary Analysis(MDA) generally requires a large amounts of computing time for the entire design process, and therefore it is essential to introduce a Multiple Processor System (MPS) for reducing the computing time. However, when applying conventional parallel processing techniques, all of the CAE S/W requited for the MDA should be installed on all the servers making up MPS because of characteristic of MDA and it would be a great expense in CAE S/W licenses. To solve this problem, we propose a Weight-based Multiqueue Load Balancing algorithm for a heterogeneous MPS where performance of servers and CAE S/W installed on each server are different of each other. To validate the performance, a Computational experiments comparing the First Come First Serve algorithm and our proposed algorithm was accomplished.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• 제24권6호
• /
• pp.715-722
• /
• 2011

In this paper, the behavior of nuclear-power plant subjected to an aircraft impact is performed using the parallel analysis. In the erstwhile study of an aircraft impact to the nuclear-power plant, it has been used that the impact load is applied at the local area by using the impact load-time history function of Riera, and the target structures have been restricted to the simple RC(Reinforced Concrete) walls or RC buildings. However, in this paper, the analysis of an aircraft impact is performed by using a real aircraft model similar to the Boeing 767 and a fictitious nuclear-power plant similar to the real structure, and an aircraft model is verified by comparing the generated history of the aircraft crash against the rigid target with another history by using the Riera's function which is allowable in the impact evaluation guide, NEI07-13(2009). Also, in general, it is required too much time for the hypervelocity impact analysis due to the contact problems between two or more adjacent physical bodies and the high nonlinearity causing dynamic large deformation, so there is a limitation with a single CPU alone to deal with these problems effectively. Therefore, in this paper, Message-Passing MIMD type of parallel analysis is performed by using self-constructed Linux-Cluster system to improve the computational efficiency, and in order to evaluate the parallel performance, the four cases of analysis, i.e. plain concrete, reinforced concrete, reinforced concrete with bonded containment liner plate, steel-plate concrete structure, are performed and discussed.

• Journal of KIISE:Software and Applications
• /
• 제35권2호
• /
• pp.128-136
• /
• 2008

Recognition of parallel structure at early stage of sentence parsing can reduce the complexity of parsing. In this paper, we propose an unsupervised language-independent probabilistic model for recongition of parallel noun structures. The proposed model is based on the idea of swapping constituents, which replies the properties of symmetry (two or more identical constituents are repeated) and of reversibility (the order of constituents is inter-changeable) in parallel structures. The non-symmetric patterns that cannot be captured by the general symmetry rule are resolved additionally by the modifier information. In particular this paper shows how the proposed model is applied to recognize Korean parallel noun phrases connected by "wa/kwa" particle. Our model is compared with other models including supervised models and performs better on recongition of parallel noun phrases.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• 제48권8호
• /
• pp.565-571
• /
• 2020

In this paper, precision and efficient nonlinear structural analysis for the aircraft wing-box model is developed. Herein, nonlinear shell element based on the co-rotational (CR) formulation is implemented. Then, parallel computing algorithm, the element-based partitioning technique is developed to accelerate the computational efficiency of the nonlinear structural analysis. Finally, computational performance, i.e., accuracy and efficiency, of the proposed analysis is evaluated by comparing with that of the existing commercial software.

• Electric Engineers Magazine
• /
• 제224권4호
• /
• pp.15-18
• /
• 2001

산업체 전력계통에서 전력설비의 이용 효율과 전력 공급의 신뢰성을 높이기 위해 여러 대의 변압기들을 병렬로 운전하는 것이 일반적으로 바람직하다. 그러나 병렬운전 대상인 변압기의 전기적 특성이 다른 경우 자기용량 대 부하 분담률이 달라 변압기 과부하 및 무효전력의 과도한 순환조류가 우려되어 병렬운전을 꺼리는 경향이 있다.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• 제22권1호
• /
• pp.35-44
• /
• 2009

This paper describes an application of domain decomposition method for parallel finite element analysis which is required to large scale 3D structural analysis. A parallel finite element method system which adopts a domain decomposition method is developed. Node is generated if its distance from existing node points is similar to the node spacing function at the point. The node spacing function is well controlled by the fuzzy knowledge processing. The Delaunay triangulation method is introduced as a basic tool for element generation. Domain decomposition method using automatic mesh generation system holds great benefits for 3D analyses. Aa parallel numerical algorithm for the finite element analyses, domain decomposition method was combined with an iterative solver, i.e. the conjugate gradient(CG) method where a whole analysis domain is fictitiously divided into a number of subdomains without overlapping. Practical performance of the present system are demonstrated through several examples.

• Journal of the Korean Institute of Telematics and Electronics D
• /
• 제36D권3호
• /
• pp.48-58
• /
• 1999

In this paper, a new parallel computation method, which fully utilize the parallel processors both in mesh generation and FEM calculation for 2D/3D process simulation, is presented. High performance parallel FEM and parallel linear algebra solving technique was showed that excessive computational requirement of memory size and CPU time for the three-dimensional simulation could be treated successively. Our parallelized numerical solver successfully interpreted the transient enhanced diffusion (TED) phenomena of dopant diffusion and irregular shape of R-LOCOS within 15 minutes. Monte Carlo technique requires excessive computational requirement of CPU time. Therefore high performance parallel solving technique were employed to our cascade sputter simulation. The simulation results of Our sputter simulator allowed the calculation time of 520 sec and speedup of 25 using 30 processors. We found the optimized number of ion injection of our MC sputter simulation is 30,000.

• Journal of Korea Water Resources Association
• /
• 제47권11호
• /
• pp.1051-1060
• /
• 2014

This study is attempted to realize an improved computation performance by combining the MPI (Message Passing Interface) Technique, a standard model of the parallel programming in the distributed memory environment, with the DHM(Diffusion Hydrodynamic Model), a inundation analysis model. With parallelizing inundation model, it compared with the existing calculation method about the results of applications to complicate and required long computing time problems. In addition, it attempted to prove the capability to estimate inundation extent, depth and speed-up computing time due to the flooding in protected lowlands and to validate the applicability of the parallel model to the actual flooding analysis by simulating based on various inundation scenarios. To verify the model developed in this study, it was applied to a hypothetical two-dimensional protected land and a real flooding case, and then actually verified the applicability of this model. As a result of this application, this model shows that the improvement effectiveness of calculation time is better up to the maximum of about 41% to 48% in using multi cores than a single core based on the same accuracy. The flood analysis model using the parallel technique in this study can be used for calculating flooding water depth, flooding areas, propagation speed of flooding waves, etc. with a shorter runtime with applying multi cores, and is expected to be actually used for promptly predicting real time flood forecasting and for drawing flood risk maps etc.

• Annual Conference on Human and Language Technology
• /
• 한국정보과학회언어공학연구회 2022년도 제34회 한글 및 한국어 정보처리 학술대회
• /
• pp.407-411
• /
• 2022

최근 COVID-19로 인해 대중의 의학 분야 관심이 증가하고 있다. 대부분의 의학문서는 전문용어인 의학용어로 구성되어 있어 대중이 이를 보고 이해하기에 어려움이 있다. 의학용어를 쉬운 뜻으로 풀이하는 모델을 이용한다면 대중이 의학 문서를 쉽게 이해할 수 있을 것이다. 이런 문제를 완화하기 위해서 본 논문에서는 Transformer 기반 번역 모델을 이용한 의학용어 탐지 및 해석 모델을 제안한다. 번역 모델에 적용하기 위해 병렬말뭉치가 필요하다. 본 논문에서는 다음과 같은 방법으로 병렬말뭉치를 구축한다: 1) 의학용어 사전을 구축한다. 2) 의학 드라마의 자막으로부터 의학용어를 찾아서 그 뜻풀이로 대체한다. 3) 원자막과 뜻풀이가 포함된 자막을 나란히 배열한다. 구축된 병렬말뭉치를 이용해서 Transformer 번역모델에 적용하여 전문용어를 찾아서 해석하는 모델을 구축한다. 각 문장은 음절 단위로 나뉘어 사전학습 된 KoCharELECTRA를 이용해서 임베딩한다. 제안된 모델은 약 69.3%의 어절단위 BLEU 점수를 보였다. 제안된 의학용어 해석기를 통해 대중이 의학문서를 좀 더 쉽게 접근할 수 있을 것이다.