• 한국수소및신에너지학회논문집
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• 제33권2호
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• pp.158-163
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• 2022

The test method on the Type II high-pressure hydrogen storage tanks made of the metal wire hoop winding is a complex and high risk. Also closeup on the tank being test is difficult. In this study, we studied a mechanical test method for a high-pressure hydrogen tanks. This method must be simple, risk-free and possible to observe the change in microscopic behavior of a metal wire on a liner. As the results, it was possible to observe the microscopic behavior on the metal wire by the mechanical test method. Also, a simple and risk-free test was possible compared to the conventional test method for high pressure hydrogen tanks.

• 한국경영과학회지
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• 제12권2호
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• pp.36-41
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• 1987

This paper presents a heuristic algorithm for solving the simple facility location problem. Its main procedure is essentially of 'add' type, which progressively selects facilities to open according to a certain criterion derived from the analysis of the linear programming dual. Computational experience with test problem from the literature is presented.

• 대한의생명과학회지
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• 제2권1호
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• pp.49-55
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• 1996

대장균군 검사용 간이 시험지는 본 실험실에서 국내 최초로 고안, 개발하였으며 이 간이 시험지법은 현장 검사법의 하나로 대장균군이 내는 succinic acid dehydrogenase 때문에 tetrazolium salt가 환원되어 적색 반점을 형성하는 것을 이용한 방법으로서 이 간이 시험지의 제조는 대체로 종래의 표준 평판법과 거의 동일한 조성의 배지와 시약을 사용하여 여지에 흡착시킨 후, 건조시켜($60^\circ$C) 멸균한 것으로 표준 평판법과 어떤 상관관계가 있는가를 검토하였다. 이 간이 시험지의 제조에서는 bile salt No. 3를 deoxycholate로 대체하여 제조 원가를 절감하였고, 또한 일본에서 현재 시판되고 있는 제품과 품질 비교시험을 하여 더 좋은 결과를 얻었으며 종래의 표준 평판법과 비교하였을 때도 오히려 표준 평판법 (24-48시간 배양)보다 빠른 시간(16-20시간 배양)내에 판정할 수 있는 이 점이 있으며, 표준 평판법에서는 없어서는 안될 배지나 배양 접시, pipette등의 자료 및 기구가 일체 필요없고 언제 어디서나 현장에서 직접 시험할 수 있어 매우 간편하며 또한 저렴한 가격으로 제조 할 수 있는 경제성이 높은 이점을 갖고 있다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.1358-1366
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• 2006

In order to study the effects of shell contents on the liquefaction resistance of the shelly sand, NGI cyclic simple shear tests were performed for the shelly sands with shell contents of 0%, 5%, 10%, 20% and 30% under the effective vertical stress of 50kPa, 100kPa and 150kPa for 40% and 55% of relative density, respectively. Cyclic simple shear test results showed that for the low effective vertical stress, liquefaction resistance increased rapidly with the increase of shell contents in both 40% and 55% relative density. On the other hand, for the high effective vertical stress, the liquefaction resistance increased slightly in 40% relative density whereas the resistance was almost same in 55% relative density. Liquefaction resistance decreased with increasing effective vertical stress for both 40% and 55% relative density. In the same effective vertical stress and shell contents, liquefaction resistance increased with the increase of relative density of sands.

• 교육시설 논문지
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• 제18권3호
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• pp.23-33
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• 2011

This study investigates the evaluation on simple comparison and seeking hidden figures works under LED illumination conditions according to three types of color temperatures (7000K, 5000K, 3000K) in the classroom, Since the objective of this study is to develop an electric lighting conditions suitable for students in the classroom, the performance of concentration and visual discrimination by students under three types of LED illumination conditions were analyzed. The 4 kinds of simple tests concerning with concentration and 2 types of tests for visual discrimination were developed, and test results under natural light and LED illumination by 3 types of color temperatures were analyzed. There were differences on concentration as well as visual discrimination performance in most cases by t-test ($p{\leq}0.05$). For further analysis among three types of color temperatures and natural light, ANOVA tests were performed. The test results shows that illumination condition plays an important role when students try to concentrate on simple comparison of characters, figures or colors and seek hidden figures. The experimental results of this study might be applied to designing better luminous environment.

• 한국지진공학회논문집
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• 제23권5호
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• pp.279-288
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• 2019

Safety-related cabinets and their electrical parts, such as relays and switches in nuclear power plants, should maintain continuous functioning, as well as structural safety according to the nuclear regulatory guidelines. Generally, an electrical part is qualified if its functioning is maintained without abnormality during excitement by motion compatible with the test response spectrum, which is larger than its in-cabinet response spectrum (ICRS). ICRS can be determined by shake-table test or dynamic analysis. Since existing cabinets in use can hardly be stopped and moved, dynamic analysis is preferred over shake-table test in determining ICRS. The simple method, suggested by the Electric Power Research Institute (EPRI) to determine ICRS, yields conservative or non-conservative results from time to time. In order to determine that the ICRS is better than EPRI method in a simple way, Ritz method considering global and local plate behaviors was suggested by Gupta et al. In this paper, the Ritz method is modified in order to consider the rocking and frame behaviors simultaneously, and it is applied to a simple numerical example for verification. ICRS is determined by Ritz method and compared with the results by finite element method (FEM). Based on this numerical example, recommendations for using Ritz method are suggested.

• 한국시뮬레이션학회논문지
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• 제19권3호
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• pp.17-25
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• 2010

선박 조종 시뮬레이션을 구성하는 기동 모델은 대상 선박의 동역학적인 특성을 현실에 가깝게 구현해야 하며, 신속한 계산 및 결과 처리가 가능하여야 한다. 다중 선박을 대상으로 하는 실시간 조종 시뮬레이션에서는 계산 시간 단축을 위해 일반적으로 선회각이나 선회율, 또는 전진 속도에 대한 1차 미분방정식 모델을 사용하여 선박의 움직임을 구현하게 된다. 본 논문에서는 대상 선박의 선회 시험 정보가 주어져 있을 경우 이를 이용한 선박의 단순 기동 모델링 및 계수 추정법을 제안하였다. 전진속도가 일정한 모델과 전진 속도의 변화를 고려한 모델의 계수 추정법을 수학적으로 전개하였으며, 실선 선회 시험 자료를 이용하여 제안된 모델의 유용성을 검증하였다.

• Communications for Statistical Applications and Methods
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• 제3권2호
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• pp.197-204
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• 1996

We consider a two sample rank test for a bivariate mixture distribution based on Johnson's quantile score. The test statistic is simple to calculate and the exact distribution under the null hypothesis is obtained. A numerical example is given.

• Structural Engineering and Mechanics
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• 제27권6호
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• pp.651-670
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• 2007

An experimental study to evaluate a redundancy capacity in simple span two plate-girder bridges, which are generally classified as a non-redundant load path structure, has been performed under the condition that one of the two girders is seriously damaged. The bottom lateral bracing was selected as an experimental parameter and two 1/5-scale bridge specimens with and without bottom lateral bracing have been prepared. The loading tests were first performed on the intact specimens without cracked girder within elastic range. Thereafter, the ultimate loading tests were conducted on the damaged specimens with an induced crack at the center of a girder. The test results showed that the cross beams and concrete deck redistributed partly the applied load to the uncracked girder, but the lateral bracing system played a significant role of the load redistribution when a girder was damaged. The redundancy was evaluated based on the test results and an appropriate redundancy level was evaluated when the lateral bracing was provided in a seriously damaged simple span two-girder steel bridge.

• 한국지반공학회지:지반
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• 제6권4호
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• pp.53-64
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• 1990

말뚝의 지지력을 예측키 위한 수많은 방안들이 제안되어 왔으나,말뚝 재하시험에 의하는 방법 외에는 신뢰도가 낮은 실정이다. 그럼에도 불구하고 말뚝 재하시험 수행에는 많은 비용과 시간이 소요되어 극히 제한된 경우에만 적용되고 있다. 본 연구에서는 새로운 말뚝재하시험, "간편한 말뚝 재하시험 (SPLT)방법"을 소개한다. SPLT에서는 분리할 수 있는 선단부와 축소된 선단부가 시험말 뚝에 설계되어, 주면마찰력이 말뚝 선단부의 침하를 야기시키는 반력으로 작용하게 된다. 이에 따라 하중재하장치 또는 하중의 제작,설치 및 제거 과정이 생략될 수 있다. 생략될 수 있다.