• 정보처리학회논문지D
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• 제12D권1호
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• pp.13-20
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• 2005

조인 연산은 데이터베이스 시스템의 가장 기본적이고 중요한 연산이며, 큰 수행 비용을 필요로 하는 연산이다. 지금까지 효율적인 조인 연산의 구현과 평가를 위한 다양한 연구가 진행되었다. 기존의 조인 연산 평가는 구현자 관점에서 우수한 알고리즘을 규명하기 위해 개발되었다. 본 논문은 사용자 관점에서 조인 연산 성능을 평가하는 조인 연산 평가 방법론을 기술한다. 본 성능 평가는 사용자가 자신의 업무에 적합한 조인 연산을 수행하는 데이터베이스 시스템을 선택하는데 도움을 준다. 본 논문에서는 두 가지 조인 범주와 여섯 가지의 조인 성능 영향 요소를 고려하여 42개의 평가 질의를 제안한다. 마지막으로 제안된 방법론에 따라 두 개의 상용 데이터베이스 시스템을 대상으로 구현하고 성능 평가 결과를 기술하였다.

• Nuclear Engineering and Technology
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• 제13권2호
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• pp.73-84
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• 1981

B$\Phi$rrensen은 3차원적 노심분석에 긴 시간이 요구되는 유한차분법의 대안으로서 경수형 원자로의 전체출력분포를 계산하는데 한가지의 coarse mesh 방법을 제안하였다. 이 방법은 계산시간이 매우 짧은 것으로 알려져 있지만. 그 계산의 정확도에 대한 것은 아직까지 알려져 있지 않다. 본 논문에서는 B$\Phi$rrensen의 방법을 IAEA benchmark 문제와 RIS$\Phi$ benchmark 문제에 적용시켜서 계산시간과 정확도에 대해서 고찰하였다. 두 문제에서 노심-반사체와의 경계조건과 B$\Phi$rrensen의 모델상수들의 개선으로 출력분포 계산의 정확도를 상당히 높힐 수 있었다.

• 한국IT서비스학회지
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• 제5권3호
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• pp.99-108
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• 2006

Public institutions are considering adoption of open-source software in the process of information projects. However, there doesn't exist reliable information about an adoption process for open-source software. Performance and stability problems of this software also persist, as a result, current open-source software is not widely used. As a software market and industry grows, Benchmark test has been performed more often than before in order to help customers understand and select the most appropriate product among myriad similar ones. It is certain that more objective and trustful data evidence should be obtained by way of utilizing the procedures and methods of Benchmark Test in decision making process for selecting an open-source software. For this research, Benchmark test was applied as a way of demonstrating performance verification of an open-source software in the public institutions. It is certain that more objective and trustful data evidence should be obtained by way of utilizing the procedures and methods of Benchmark Test in decision making process for selecting an open-source software. It also introduces a case study of a information system, which selected and implemented open-source software, in order to confirm the validity of this research. This research will serve as a guideline to adopt open-source software in governments as well as public institutions.

• Nuclear Engineering and Technology
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• 제50권2호
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• pp.280-291
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• 2018

In the framework of OECD/NEA Working Group on Fuel Safety, a RIA fuel-rod-code Benchmark Phase I was organized in 2010-2013. It consisted of four experiments on highly irradiated fuel rodlets tested under different experimental conditions. This benchmark revealed the need to better understand the basic models incorporated in each code for realistic simulation of the complicated integral RIA tests with high burnup fuel rods. A second phase of the benchmark (Phase II) was thus launched early in 2014, which has been organized in two complementary activities: (1) comparison of the results of different simulations on simplified cases in order to provide additional bases for understanding the differences in modelling of the concerned phenomena; (2) assessment of the uncertainty of the results. The present paper provides a summary and conclusions of the second activity of the Benchmark Phase II, which is based on the input uncertainty propagation methodology. The main conclusion is that uncertainties cannot fully explain the difference between the code predictions. Finally, based on the RIA benchmark Phase-I and Phase-II conclusions, some recommendations are made.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2445-2453
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• 2021

Since the nuclear data forms a vital component in reactor physics computations, the nuclear community needs processing codes as tools for translating the Evaluated Nuclear Data Files (ENDF) to simulate nuclear-related problems such as an ACE format that is used for MCNP. Errors, inaccuracies or discrepancies in library processing may lead to a calculation that disagrees with the experimentally measured benchmark. This paper provides an overview of the processing and preparation of ENDF/B-VIII.0 incident neutron data with NECP-Atlas and NJOY codes for implementation in the MCNP code. The resulting libraries are statistically inter-compared and tested by conducting benchmark calculations, as the mutualcomparison is a source of strong feedback for further improvements in processing procedures. The database of the benchmark experiments is based on a selection taken from the International Handbook of Evaluated Criticality Safety Benchmark Experiments (ICSBEP handbook) and those proposed by Russell D. Mosteller. In general, there is quite good agreement between the NECP-Atlas1.2 and NJOY21^(1.0.0.json) results with no substantial differences, if the correct input parameters are used.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 추계학술발표회논문집(1)
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• pp.113-120
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• 1996

원전 일차계통 내부구조물에 심각한 손상을 유발할 수 있는 금속파편의 탐지 및 진단기술을 비교하고 공유하기 위하여 LPM(loose part monitoring) Benchmark Exercise를 수행하였다. 금속파편 충격에 대한 Benchmark Data는 미국 Catawba Unit 2에서 취득하였으며 6가지 질량의 강구를 다른 높이에서 낙하시킨 36 종류의 data set으로 구성되어 있다. 출격위치 및 강구의 질량을 추정한 결과 실제값과 잘 일치하였고 국내 분석기술의 유용성을 보였으며 외국기술과 비교할 때 동등한 수준임을 확인하였다.

• KIEE International Transactions on Power Engineering
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• 제5A권3호
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• pp.207-213
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• 2005

This paper deals with the development of benchmark systems based on the Korea Electric Power Corporation (KEPCO) system. A novel procedure for constructing a dynamic equivalent system of the KEPCO system is proposed. By using such a system, various scenarios can be simulated and compared with the original system. The results of the simulation show the benefits of the proposed equivalent system and its validity is confirmed by applying it to the KEPCO system.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 춘계학술발표회논문집(1)
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• pp.39-44
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• 1997

The International Criticality Safety Benchmark Evaluation Project (ICSBEP) is under way for the purpose identifying, evaluating, and compiling benchmark critical experiment data into a standardized format that allows criticality analysts to easily use the data to validate calculational methods and cross sections. As part of this activity, PNL30-35 experiments, which had been adopted as benchmark problems by CSEWG in 1970s, were reevaluated, which results in some additions and modifications: changes in fuel number density, modification to the experimental keff, modifications to the soluble boron concentration for PNL-31, and addition of an uncertainty in the benchmark-model k$_{eff}$./.

• Structural Engineering and Mechanics
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• 제68권1호
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• pp.17-38
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• 2018

In this paper, we compare and assess the performance of the standard 3- and 6-node MITC shell elements (Lee and Bathe 2004) with the recently developed MITC triangular elements (Lee et al. 2014, Jeon et al. 2014, Jun et al. 2018) which were based on the partitions of unity approximation, bubble node, or both. The convergence behavior of the shell elements are measured in well-known benchmark tests; four plane stress tests (mesh distortion test, cantilever beam, Cook's skew beam, and MacNeal beam), two plate tests (Morley's skew plate and circular plate), and six shell tests (curved beam, twisted beam, pinched cylinder, hemispherical shells with or without hole, and Scordelis-Lo roof). To precisely compare and evaluate the solution accuracy of the shell elements, different triangular mesh patterns and distorted element mesh are adopted in the benchmark problems. All shell finite elements considered pass the basic tests; namely, the isotropy, the patch, and the zero energy mode tests.

• Smart Structures and Systems
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• 제17권3호
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• pp.431-444
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• 2016

This paper was written in the context of a benchmark study promoted by The Hong Kong Polytechnic University using data samples collected in an instrumented cable-stayed bridge. The main goal of the benchmark test was to study the identification of the bridge modes of vibration under different wind conditions. In this contribution, the tools developed at ViBest/FEUP for automated data processing of setups collected by dynamic monitoring systems are presented and applied to the data made available in the context of the benchmark study. The applied tools are based on parametric output only modal identification methods combined with clustering algorithms. The obtained results demonstrate that the proposed algorithms succeeded to automatically identify the modes with relevant contribution for the bridge response under different wind conditions.