• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.844-850
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• 1998

본 연구에서는 개방구(opening)을 갖는 원자력발전소 강재 격납구조물의 내력을 평가함에 있어서 기존의 실용 구조설계에 적용된 개구부가 없는 원통형 쉘의 좌굴 판정 기준이 적절하지 않음을 밝혔으며, 대안으로서 개방구(opening)를 갖는 원통형 강재 격납구조물의 재료적 비선형과 기하학적 비선형을 고려한 극한 내력 해석을 수행함으로써 중기발생기 교체작업시 유발되는 인양 하중에 대한 격납구조물의 구조적 안전성을 평가하였다. 개방구를 갖는 격납구조물에 대하여 stiffner가 있는 상태에서 크레인 하중에 대한 극한 내력을 평가해본 결과 크레인 하중이 재하될 경우, 구조물이 선형 탄성 범위에 있는 것으로 확인되었으며 개방구 주위의 국부적인 항복응력도달 상태에 대하여 10.8의 안전율을 확보 할 수 있는 것으로 계산되었다. 본 연구를 통하여 제시된 개방구를 갖는 강재 격납구조물의 극한내력 평가 방법은 유사 구조물의 구조건전성 평가에 활용될 수 있을 것으로 사료된다.

• Journal of Navigation and Port Research
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• v.39 no.3
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• pp.233-239
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• 2015

Recently, Due to variable marine accident occurred, problems relating to marine accidents have been raised. Of these accidents, designated anchorage of Korea coastal port, spcially open-sea anchorage, occurred dragging anchor and accidents are likely, due to failure to obtain a valid ship's holding power so that it is the situation unsatisfactory that ensuring the safety of the anchored ship and anchorage systematic safety management stadars for the efficent operation of the anchorage. also in case of open-sea anchorage vulnerable to external force of certain conditions due to geographical location and topographical characteristics of the port, accidents are likely dragging anchor by typoon or suddenly strong wind and secondary accidents are concerned. This paper shows standard of limit external force to ensure the safety anchorage each of ship's size through review marine accidents on Pohang port, also it is determined to be used as a basic reference for anchoring safety and efficient anchorage management.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.131-131
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• 2009

최근 환경규제가 강화되면서 친환경적인 전력생산 요구 등의 외부환경 변화에 따른 우리나라의 전력구조가 기존의 중압 집중형 발전을 탈피한 분산전원 발전에 대한 관심이 증대되고 있는 실정이다. 특히, 분산전원으로서의 전력생산은 공급의 안전성, 경쟁력 및 에너지의 지속성 등이 요구되어지는데, 재생에너지가 가지고 있는 에너지 지속성의 한계 및 설치의 제약성을 탈피할 수 있는 시스템으로 현재 연료전지시스템이 가장 근접해 있는 실정이다. 즉, 도시가스 인프라가 우수하고 인구조밀 지역이 많은 우리나라의 특성상 각 가정 및 건물에 쉽게 설치하고 공급의 안전성을 갖는 건물용 연료전지는 최근 가장 각광받고 있는 분산전원 시스템 중의 하나이다. 올해부터 모니터링사업의 일환으로 수용가에 설치 될 연료전지 시스템이 얼마나 안정적으로 전기와 열을 각 가정에 공급하고 시스템의 안전성을 확보하는 가는 건물용 연료전지의 분산전원으로서의 가능성 및 국민의 수용성을 증대시키는 중요한 역할을 할 것이다. 연료전지시스템은 상용전력과 연계되어 있기 때문에 시스템의 안정성 뿐만 아니라 상용전력의 변화에 대응하여 안정적인 운전을 하는지에 대한 평가가 필수적이다. 이에 따라 본 연구에서는 가정용 연료전지시스템의 성능 및 안전성평가의 일환으로 계통연계형 전력변환장치의 성능 및 안전성을 평가 하고자 한다. 연료전지 검사를 위한 계통연계형 전력변환장치의 시험평가 항목으로는 크게 정상특성성능시험, 보호기능성능시험, 과도응답특성성능시험 및 외부사고성능시험 등으로 나뉘어진다. 본 연구에서는 외부사고 성능시험 항목들인 출력측 단락시험, 계통전압 순간정전?순간강하시험 및 부하차단 시험 등을 통하여 외부사고에 대한 성능 및 안전성을 평가하였다. 외부사고 성능시험의 주 목적은 시스템의 이상 운전이 아니라 외부의 영향에 따른 시스템의 안전성 및 전력품질을 평가한다. 출력측 단락시험을 수행하기 위해서 전력변환장치를 정격 출력 전압, 정격 출력 주파수 및 정격 출력에서 운전한 후, 교류 전원장치는 단락 전류를 검출하여, 사고 발생 후 0.3초 이내에 개방하도록 설정하였다. 여기서, 단락 저항 Rsc를 정격 전류의 10배 이상에 해당하는 부하와 같은 값으로 설정하였다. 스위치 SWSC를 폐로하여 단락 상태를 만들며, 이 때 전력변환장치의 출력전류와 차단 또는 정지 시간을 측정하였다. 실험 결과에 대한 판정기준은 단락전류를 검출하여 0.5초 이내에 개폐기 개방 또는 게이트 블록 기능이 동작하여 시스템을 안정하게 정지시키고 시스템 어떤 부위에도 손상이 없어야 한다. 실험 결과 파워컨디셔너의 출력전류 및 차단 또는 정지된시간이 40ms로 나타났고, 출력전류의 파형도 매우 안정함을 볼 수 있었다. 이와 같이 모든 실험을 수행한 결과 외부사고에 대하여 시스템이 안전하게 정지하는 등 연료전지 시스템의 안전성을 확인하였다.

• Journal of the Korean Society of Radiology
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• v.16 no.6
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• pp.741-749
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• 2022

Radiography-Testing that verify the quality of welding structures without destruction are overwhelmingly used in industries, but many safety precautions are required as radiation is used. The workers for Radiography-Testing perform the inspection by moving the Iridium-192 radiation source embedded in the transport container of the gamma-ray irradiator within or outside the facility. The general facility is completely blocked about radiation from the outside with thick concrete, but if it is difficult for worker to handle object of inspection, facilities ceiling can be opened. A general facility may be constructed using a theoretical dose evaluation method because all exterior facilities are blocked, but if the ceiling is open, it is not appropriate to evaluate radiation safety with a simple theoretical calculation method due to the skyshine effect. Therefore, in this study, the radiation safety of the facility was evaluated in the actual field through an ion chamber survey-meter and an accumulated dose-meter called as OSLD, and the actual evaluation environment was modeled and evaluated using the Monte Carlo simulation code as FLUKA. According to the direction of the irradiation, the radiation dose at the facility boundary was difficult to meet the standards set by the regulatory authority, and radiation safety could be secured through additional methods. In addition, it was confirmed that the simulation results using the Iridium-192 source were valid evaluation with the actual measured results.

• Korean Journal of Psychosomatic Medicine
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• v.13 no.2
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• pp.85-94
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• 2005

Objectives: This prospective and open-label study was conducted to evaluate the efficacy and safety of quetiapine and haloperidol in patients with delirium. Methods : Fourty patients(19 patients in a quetiapine group : 21 patients in a haloperidol group) with delirium by DSM-IV were treated with flexible doses of open-label qvetiapine and haloperidol. To evaluate the primary efficacy of the medication, scores from the Korean version of Delirium Rating Scale(K-DRS) were assessed every seven days and to evaluate the secondary efficacy and safety, scores from the Clinical Global Impression-Severity, Korean Version of Mini-Mental State Examination, and the Drug-Induced Extrapyramidal Symptoms Scale were assessed at the baseline and the seventh day. Data were gathered from November 2004 to June 2005. Results : K-DRS scores for each group decreased significantly over the study period; however, no significant differences between groups were found. The group-by-time effect was not significant. In addition, there was no significant difference in the frequency of response to drugs between the two groups. No patients reported clinically significant side effects. Conclusion : These data show no significant difference in the efficacy and safety between quetiapine and haloperidol in the treatment of delirium. Since haloperidol has a great possibility of causing a extrapyramidal side effect resulted by previous studies, it is expected that quetiapine, a renowned medication with low side effects, may be a useful alternative agent to haloperidol, the classical antipsy-chotics, in the treatment of delirium.

• Fire Science and Engineering
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• v.34 no.2
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• pp.156-165
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• 2020

In this paper, the application of evacuation delay time (Cognition time + initiation time) and examine the degree of opening of fire doors in households for evaluating evacuation safety and suggest a realistic alternative. In order to proceed with this study, first of all, the preliminary investigation on evacuation safety evacuation of residential-type buildings (Apartment, urban living houses, etc.) among the performance-oriented design targets of Gwangju Metropolitan City, which was implemented until June 2018. Then, for the two representative types that are commonly used among the previously surveyed buildings, evacuation delay time is applied to W1, W2, and respectively simulating the opening of the doors is applied to th full open, 1/4 open, the leakage gap and evacuation safety evaluation was performed. As a result of evaluating evacuation safety was found that it is difficult to secure evacuation safety regardless of evacuation delay time W1 and W2 when the fire door is fully open and 1/4 open, Only when the leakage gap is applied evacuation safety was ensured even if evacuation delay time W2 was applied. Therefore, when a residential building is subject to performance-oriented design, evaluating the application of W2 rather than W1 is considered for evacuation delay time to reflect concern about privacy infringement due to CCTV installation, etc. In order to secure the Smoke blocking performance of the fire door and to improve the performance-oriented design, I would like to propose to consider the method of applying a leak gap to the degree of opening of the fire door. Through this, it is expected that the performance-oriented design will be a step further by performing evacuation safety evaluation with more realistic data.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.1
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• pp.65-71
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• 2016

In recent years, 3D printing has received increasing attention due to releases of low-cost 3D printers based on open-source platform. 3D printing is expected to reduce the barrier to entry in the traditional manufacturing processes by increasing flexibility and creating an advantage to manufacture customized products at low costs. In this study, a unique eyeglass frame was designed to have a snake shape, which has an asymmetric geometry unlike traditional frames. The eyeglass frame was designed in a customized manner by reflecting dimensional characteristics of a customer's face. Finite element analysis was performed to investigate the structural safety of the 3D printed frames during the assembly process. The analysis also considered the effect of anisotropic material properties as determined by tensile tests. The eyeglass frame was then printed using the customized sizes and the best building process. The eyeglass frame was successfully assembled with lenses and without structural failure during its assembly procedure.

• The Magazine of the IEIE
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• v.20 no.2
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• pp.87-100
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• 1993

정보통신 안전 서비스의 제공에 따라 사업자 측면에서 관련 장비의 상호운용성 확보, 연구개발 또는 도입제품 평가의 용이성과 제품생산자 측면에서는 생산원가의 저렴화를 위하여 반드시 표준화가 필요하다. 본 논문에서는 안전기술의 표준화 연구를 수행하는 주요 국제기구인 ISO/IEC JTC1 SC21, SC27과 CCITT SG VII 등의 활동과 이에 대응한 국내 표준화 그룹들과 관련 기관들의 활동을 소개하였다. 또한 이러한 국내외 활동과 통신 사업자의 사업여건을 고려하여 통신 사업자가 정보통신 사업에 잇어서 소요되는 안전기술 및 이의 표준화 방향을 제시하고자 한다.

• Journal of the Korean Society for Railway
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• v.11 no.4
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• pp.349-356
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• 2008

Put Safety-critical systems related to the railway communications are currently undergoing changes. Mechanical and electro-mechanical devices are being replaced by programmable electronics that are often controlled remotely via communication networks. Therefore designers and operators now not only have to contend with component failures and user errors, but also with the possibility that malicious entities are seeking to disrupt the services provided by theirs systems. Recognizing the safety-critical nature of the types of communications required in rail control operations, the communications infrastructure will be required to meet a number of safety requirements such as system faults, user errors and the robustness in the presence of malicious attackers who are willing to take determined action to interfere in the correct operation of a system. This paper discusses the safety strategies employed in the railway communications and proposes a security mechanism for Korean railway communication system. We present the developed communication safety evaluation tool based on the proposed security mechanism and also evaluate its protecting capability against the threats of masquerading, eavesdropping, and unauthorized message manipulation.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.2
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• pp.47-58
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• 2013

The purpose of this study is to categorize the types of sidewalk cafes, and to evaluate design factors with types of sidewalk cafes for street revitalization. Consequently, it may suggest efficient and systemic policies for the guidelines of sidewalk cafes. To ensure this end, the types of sidewalk cafes were categorized from the street relationship perspective by site investigation. A literature review and importance analysis were used to select the evaluation criteria, and the data were analyzed by statistic methods such as descriptive analysis and factor analysis. As a result, five main factors of the evaluation criteria were contracted: accessibility, aesthetics, identity, environmental, culturedness. Cumulative factor loading of these five factors was 68.731%, which was quite high. And the evaluation using the Likert scale was performed by 4 experts. Types of sidewalk cafes were categorized into 5 types: protruding, gating, blending stereoscopic, elevation angle, and sign provision from the street relationship perspective. On the evaluation by type, aesthetics and culturedness were the worst evaluated in the protruding type and the gating type, culturedness was the worst in the blending stereoscopic type, accessibility, aesthetics, culturedness were the worst in the elevation angle type, and accessibility, identity, culturedness were the worst in the sign provision type. On the evaluation by the indicators, culturedness was the worst evaluated, and on the evaluation by criteria, 'safety for impaired persons', 'interest of programs', 'openness of entrance' were the worst. It is recommended that a survey of importance-performance analysis focused on users be conducted.