• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 제38회 하계학술대회
• /
• pp.31-32
• /
• 2007

In this paper, a fault section detection method is proposed for ungrounded system in the case of a single line-to-ground fault. A conventional method is used for faulted feeder selection according to the angular relationship between zero-sequence currents of the feeders and zero-sequence voltage of the system. Fault section detection is based on the comparison of phase angle of zero-sequence current. Proposed method has been testified in a demo system by Matlab/Simulink simulations. Based on Distribution Automation System(DAS), Feeder Remote Terminal Unit(FRTU) is used to collect those necessary data, at present a demo system is under developing using Manufacturing Message Specification (MMS) in IEC61850 standard.

• 핵의학기술
• /
• 제27권1호
• /
• pp.55-61
• /
• 2023

Purpose In this study, the monthly population distribution was calculated for statistical verification of 10 tests (CA19-9, CA15-3, testosterone, PTH, calcitonin, AFP, CEA, CA72-4, PSA, estradiol) with changed reagents, and the trend of change By comparing and analyzing the results, we want to verify the accuracy of the results and improve the reliability of the test. Materials and Methods From June 2021 to February 2023, for the 10 items in which the reagent was changed, the monthly percentage and standard deviation index before and after the reagent change were compared, respectively. At this time, the reference value was arbitrarily set for the comparison group in consideration of the reference value of the test item, and the groups were subdivided and compared, and the standard deviation index allowed range was -2.0 or more and 2.0 or less. Results For CA19-9, CA15-3, AFP, CEA, and calcitonin 5 test items, the change in monthly ratio in all test sections before and after the reagent change was kept constant. On the other hand, for CA72-4, PSA, testosterone, PTH, and estradiol items, the standard deviation index exceeded the acceptable standard after changing the reagent. CA72-4 test items showed an increasing trend in standard deviation index in the test section exceeding the reference value. In the case of the PSA test item, the maintenance ratio of 0.04 ng/mL was significantly decreased after changing the reagent. The testosterone test item had a standard deviation index of -2.5 in the test section exceeding 10.1 ng/mL after changing the reagent, and the standard deviation index of the PTH test item was out of the acceptable range in all test sections. It was confirmed that the estradiol test item showed an overall increase in the result value. Conclusion Through this study, the continuity and accuracy of the test results could be verified. It is considered that the stability of the test can be secured by analyzing the factors affecting the test result and solving the cause for the test item whose standard deviation index is out of the acceptable standard.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 1999년도 춘계학술대회 논문집
• /
• pp.232-237
• /
• 1999

The standardization urban transit project has been started by government and the Korean standard electrical railcar has been designed. The bodyshell of standard railcar is made of aluminium alloy. In the present paper, the design of its bodyshell is evaluated in the viewpoint of strength analysis. The loading condition is based on the 'Test Methods of Static Load for Body Structure of Electrical Multiple Unit', standard specification. The bodyshell of Korean standard EMU consist of longitudinal extrusion members which are double-skin structure type. For the purpose of security and lightening we decided the section of the aluminium carbody through the size optimization in this paper Hereafter this paper will contribute to the shape optimization.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
• /
• pp.121-123
• /
• 2013

Research on the "Modernized Korean traditional housing" (Hanok) has been actively studied in succeeding to Korean traditional housing and providing the public with housing that required for modernized life style. The purpose of this study is to classify work sections for Hanok specifications. This paper analyzed the concepts and characteristics of existing specifications. It was found that the absence of standard classifications is one of the causes of missing work items and mixed scopes. Also, the contents of carpentry works have low level of details. Therefore, Hanok specifications, in this study, are required to have upper level standards and to encompass traditional and new construction methods. Further research will develop standard classifications, standard codes, and automated systems of Hanok specifications for improving quality and effectiveness.

• 무역학회지
• /
• 제44권1호
• /
• pp.177-191
• /
• 2019

Global trade protectionism has increased further and U.S. priorities and protectionism have strengthened since Trump took office in 2017. Trump administration is actively implementing tariff measures based on U.S. domestic trade laws rather than the WTO rules and regulations. In particular, the American government has recently been imposing high tariffs due to national security and imposing economic sanctions on other countries' imports. According to the U.S. Trade Expansion Act Section 232, the American government imposed additional tariffs on steel and aluminum imports to WTO member countries such as China, India, and EU etc. on march 15, 2018. Thus, this study aims to investigate whether the U.S. Trade Expansion Act Section 232 is consistent with GATT/WTO rules by comparing the legal basis of US / China / WTO regulations related to Section 232 of the U.S. Trade Expansion Act, and gives some suggestions for responding to the Section 232 measure. As the Section 232 measure exceeded the scope of GATT's Security Exceptions regulation and is very likely to be understood as a safeguard measure. If so, the American government is deemed to be in breach of WTO's regulations, such as the most-favored-nation treatment obligations and the duty reduction obligations. In addition, American government is deemed to be failed to meet the conditions of initiation of safeguard measure and violated the procedural requirements such as notification and consultation. In order to respond to these U.S. protection trade measures, all affected countries should actively use the WTO multilateral system to prevent unfair measures. Also, it is necessary to revise the standard jurisdiction of the dispute settlement body and to explore the balance of the WTO Exception clause so that it can be applied strictly. Finally, it would be necessary for Chinese exporters to take a counter-strategy under such trade pressure.

• 재활복지공학회논문지
• /
• 제11권2호
• /
• pp.187-198
• /
• 2017

이 연구에서는 우리나라의 모바일 앱 접근성 KS, 미국의 재활법 508조 개정 표준 및 유럽의 BBC 지침을 기준으로 개방형 플랫폼인 안드로이드 모바일 뱅킹 앱의 접근성을 분석하였다. 실험 결과, 우리나라 8개 시중은행의 모바일 뱅킹 앱 중 상기 3가지 표준의 세부 항목을 모두 만족하는 앱은 한 곳도 없었다. 대표적인 위반 항목은 대체 텍스트 미비, 키보드 초점 위반, 컨트롤 크기 및 간격 미준수, 명도대비 비율 낮음 등이었다. 이들 위반사례는 시각장애인, 상지장애인 및 저시력인과 고령자의 접근을 불가능하게 만든다는 점에서 치명적인 오류이다. 모바일 뱅킹 앱이 접근성을 준수하지 않는 원인에 있어서는 모바일 앱 개발자와 제공자들의 접근성에 관한 인식이 낮고 접근성 구현 방법을 제대로 숙지하지 못한 것으로 분석되었다. 우리나라의 모바일 앱 접근성 지침을 재활법 508조 개정 표준 및 BBC 표준과 비교한 결과, 많은 항목이 누락되어 있었다. 또한 평가 기준이 모호하고 추상적이어서 개발자들이 구체적으로 참고하기 어려운 측면이 있는 것으로 판단되었다. 따라서 모바일 앱 접근성 향상을 위한 개발자 및 정부의 노력과 더불어 표준의 보완이 필요하다.

• Steel and Composite Structures
• /
• 제47권2호
• /
• pp.269-287
• /
• 2023

The WGJ420 fire-resistant weathering (FRW) steel is developed and manufactured with standard yield strength of 420 MPa at room temperature, which is expected to significantly enhance the performance of steel structures with excellent fire and corrosion resistances, strong seismic capacity, high strength and ductility, good resilience and robustness. In this paper, the mechanical properties of FRW steel plates and buckling behavior of columns are investigated through tests at elevated temperatures. The stress-strain curves, mechanical properties of FRW steel such as modulus of elasticity, proof strength, tensile strength, as well as corresponding reduction factors are obtained and discussed. The recommended constitutive model based on the Ramberg-Osgood relationship, as well as the relevant formulas for mechanical properties are proposed, which provide fundamental mechanical parameters and references. A total of 12 FRW steel welded I-section columns with different slenderness ratios and buckling load ratios are tested under standard fire to understand the global buckling behavior in-depth. The influences of boundary conditions on the buckling failure modes as well as the critical temperatures are also investigated. In addition, the temperature distributions at different sections/locations of the columns are obtained. It is found that the buckling deformation curve can be divided into four stages: initial expansion stage, stable stage, compression stage and failure stage. The fire test results concluded that the residual buckling capacities of FRW steel columns are substantially higher than the conventional steel columns at elevated temperatures. Furthermore, the numerical results show good agreement with the fire test results in terms of the critical temperature and maximum axial elongation. Finally, the critical temperatures between the numerical results and various code/standard curves (GB 51249, Eurocode 3, AS 4100, BS 5950 and AISC) are compared and verified both in the buckling resistance domain and in the temperature domain. It is demonstrated that the FRW steel columns have sufficient safety redundancy for fire resistance when they are designed according to current codes or standards.

• 한국콘텐츠학회:학술대회논문집
• /
• 한국콘텐츠학회 2004년도 추계 종합학술대회 논문집
• /
• pp.495-500
• /
• 2004

The neutron capture cross section of $^{99}Tc$ has been measured relative to the $^{10}B$(n,g) standard cross section by the neutron time-of-flight(TOF) method in the energy range of 0.007 eV to 47keV using a 46-MeV electron linear accelerator(linac) at the Research Reactor Institute, Kyoto University(KURRI). In order to experimentally prove the result obtained, the supplementary cross section measurement has been made from 0.3 eV to 1 keV using the Kyoto University Lead slowing-down Spectrometer(KULS) coupling to the linac. The relative measurement by the TOF method has been normalized to the reference value(20.01 b) at 0.0253 eV and the KULS measurement to that by the TOF method. The existing experimental data and the evaluated capture cross sections in ENDF/B-VI, JENDL-3.2, and JEF-2.2 have been compared with the current measurements by the linac TOF and the KULS experiments. The energy dependency of the KULS data is close to that of the TOF data which are energy-broadened by the resolution function of the KULS.

• Nuclear Engineering and Technology
• /
• 제21권4호
• /
• pp.245-258
• /
• 1989

열중성자로의 핵계산을 위한 69군 단면적 라이브러리를 생산하였다. 기본 평가핵자료로는 IAEA Nuclear Data Section에서 수집된 자료가, 그리고 이를 처리하여 군정수화 하는데는 NJOY코드가 이용되었다. 새로이 마련된 라이브러리의 유용성을 검증하기 위해 각기 산화우라늄과 금속 우라늄 연료로 구성된 임계실험치를 WIMS-KAERI 코드로 계산된 결과와 비교, 검토하였다. 총 88임계결과에 대해 평균 $K_{eff}$ 값 0.9997, 그리고 표준 편차 0.69%를 보였다. PWR 연료의 연소결과로 얻어진 우라늄과 플루토늄 생성량에 대한 평가에서도 전반적으로 좋은 결과를 얻었다.다.

• Computers and Concrete
• /
• 제1권3호
• /
• pp.303-324
• /
• 2004

The Component-Based Software Development (CBSD) has established itself as a sound paradigm in the software engineering discipline and has gained wide spread acceptance in the industry. The CBSD relies on the availability of standard software components for encapsulation of specific functionality. This paper presents the framework for the development of a software component for the design of general member cross-sections. The proposed component can be used in component-based structural engineering software or as a stand-alone program developed around the component. This paper describes the use-case scenarios for the component, its design patterns, object models, class hierarchy, the integrated and unified handling of cross-section behavior and implementation issue. It is expected that a component developed using the proposed patterns and model can be used in analysis, design and detailing packages to handle reinforced concrete, partially prestressed concrete, steel-concrete composite and steel sections. The component can provide the entire response parameters of the cross section including determination of geometric properties, elastic stresses, flexural capacity, moment-curvature, and ductility ratios. The component can also be used as the main computational engine for stand-alone section design software. The component can be further extended to handle the retrofitting and strengthening of cross-sections, shear and torsional response, determination of fire-damage parameters, etc.