• 대한금속재료학회지
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• 제47권1호
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• pp.7-12
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• 2009

The detailed quantitative microstructural data on the cracking of coarse constituent particles in 7075 (T651) series wrought Al-alloys have been studied using the utility of a novel digital image processing technique, where the particle cracks are generated due to monotonic loading. The microstructural parameters such as number density, volume fraction, size distribution, first nearest neighbor distribution, and two-point correlation function have been quantitatively characterized using the developed technique and such data are very useful to verify and study the theoretical models for the damage evolution and fracture of Al-alloys. The data suggests useful relationships for damage modeling such as a linear relationship between particle cracking and strain exists for the uniaxial tensile loading condition, where the larger particles crack preferentially.

• 한국지진공학회논문집
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• 제20권7_spc호
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• pp.509-516
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• 2016

Secure operation of hospitals during and right after earthquake is essential. Past lessons from earthquake damages have shown that most of the injured and the death occurred within 30 minutes after earthquake and the portion of nonstructural damage has become significant. However, hospital buildings in Korea have not prepared fully to address such rising issues. This paper is to study what type of damage patterns are related to hospital buildings and how to develop a preparedness plan to keep hospitals operational at all earthquakes if possible. This paper first reviews on past earthquake damages reported as critical to hospital buildings while classifying them into four groups: (1) structural element; (2) architectural-nostructural element; (3) medical equipments and contents; and (4) utility facility. Upon such classification, some detailed concerns can be specified under each group explicitly. Then a hierarchy for hospital building is also developed for the classified groups, which enables us to identify required things for the enhancement of seismic performance of hospital building that consists of heterogeneous elements. To upgrade the level of seismic performance for existing hospital buildings, the concept of performance-based approach can be adopted to address the heterogeneous problems in a systematic and stepwise manner. Finally a conceptual framework for the seismic risk assessment for hospital building is proposed toward the seismic enhancement of hospital buildings using performance-based approach.

• 한국재난정보학회 논문집
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• 제11권1호
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• pp.135-147
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• 2015

최근 지하공동구(Underground Common Utility Tunnels)는 도시민이 일상생활을 영위하는데 필요한 전기, 통신, 상수도, 도시 가스, 하수도뿐만 아니라 냉난방시설, 진공 집진관, 정보처리케이블 등의 시설물을 2종 이상 공동으로 수용하기 위한 지하시설물로서 국가의 중추기능을 담당하는 시설이지만, 화재 사고시 신속한 대처가 힘들고 각종 케이블 연소시 발생하는 유독가스 및 연기에 의해 공동구 내에 진입하여 진압하기가 힘들다. 따라서 화재발생시 막대한 재산피해 및 통신두절 등 국가의 중추신경이 마비됨은 물론 시민불편사항을 초래하게 된다. 따라서 본 논문은 지금까지 발생 되어온 국내,외 공동구 화재사례에서 화재발생의 주요원인으로 전기공사로 인한 합선 및 가연성케이블에 의한 열화접촉으로 화재가 발생하는 것이 대다수를 차지하고 있음에 착안하여 실제 공동구 모형을 제작하고 화재를 재현함으로서 과학적으로 화재의 성상을 분석하는데 그 목적이 있다. 화재실험은 지하공동구 내에 정온식 감지선형 감지기(Line type fixed temperature detector), 방화문(Fire door), 연결살수설비(Connection deluge set), 및 환기설비를 설치하고, 송 배전케이블은 일정구간 내화(Fireproof)도료로 도장하며, 난방관은 내화 피복된 상태에서 실험하였다. 그 결과 Type II의 경우 최고온도가 $932^{\circ}C$로 측정되었고, 일정한 온도에서 정온식감지선형감지기가 화재위치를 정확하게 수신반에 표시되었다. 그리고 Type III의 경우인 송 배전케이블은 일정구간 내화도료로 도장한 것은 내화성능이 없는 것으로 나타났고, 내화피복(Fireproof covered)된 난방관은 약 30분 정도의 내화성능이 있는 것으로 나타났다. 또한 화재뮬레이션 결과는 실물화재시험시의 화재하중(Fire load)을 입력하여 실시한 결과로서 최고온도가 $943^{\circ}C$로 실물화재실험시의 $932^{\circ}C$와 거의 일치 하였다. 따라서 공동구 화재하중만으로 화재시뮬레이션을 실시하여 화재성상에 대한 예측이 가능한 것으로 판단되며 시뮬레이션으로 얻은 열방출률(Heat release rate), 연기층의 높이, 산소(O2), 일산화탄소(CO), 이산화탄소(CO2)의 농도 등의 결과 값들은 실제 화재실험시의 값으로 적용시킬 수 있는 것으로 판단된다. 향후 본 연구에서 구축한 국내 지하공동구 화재사고에 대한 실험자료 및 매년 지속적으로 화재사례들을 분석하여 축적하고 법 규정 및 관리 메뉴얼 등을 보완함으로써 국내 지하공동구 화재사고에 대한 보다 신뢰성 있는 정보를 제공해 줄 수 있을 것이며, 효과적이고 체계적으로 지하공동구의 신설 및 유지 관리 보수에 기여할 것으로 기대된다.

• 한국가스학회지
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• 제15권6호
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• pp.20-27
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• 2011

PSM 제도와 더불어 사고 피해크기 예측기법은 국내 석유화학공장에 많이 보급되어 활용되고 있으나, 사고로 인한 영향, 즉, 작업자, 조업중단, 유틸리티에 미치는 영향을 고려하지 않고, 비상조치계획을 수립하고 있어서 다소 현실적이지 못한 문제점이 있다. 따라서 본 연구에서는 현실적인 비상조치계획을 수립하고, 위험기반 안전관리를 수행할 수 있도록 하기 위하여 석유화학공장의 설비에서 사고로 인한 피해지역과 재정적 손실을 산출하여 사고 피해크기를 비교 분석하였다. 피해지역을 기준으로 하는 경우에는 장치손상지역, 상해지역 그리고 독성지역을 동시에 고려한 안전지역을 기준으로 피해크기 등급을 산출하여야 하고, 또한 공정의 특성 및 주변 환경을 고려하면 피해지역을 기준으로 하는 것보다 재정적 손실을 기준으로 하는 것이 현실적인 사고 피해크기 산출방법이었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1672-1677
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• 2005

The Heat exchanger to be used in the place of business that is presented an utility period comes to be long and the problem of the length of life shares by the manufacture course and using environment factor. Consequentl, it is came to the front problem of inspection, repair, exchange, the utility stopping, safety and confidence. As a result the possibility which the large safety accident can happen comes to be high. It leads mostly to the large accedent when the explosion accident happens. to keep this, The system which the regular period passes to disuse the structure is prepared but The phenomenon which Time and the strength characteristic of the material change, namely Deradation. but It can't be a preventable solution by accident to the damage. Consequentl, This research can take important role to prevent an every kind accident for domestic pressure vessel by evaluating the mechnical characteristic change of meterial, the structure safety and residual life etc.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.127-131
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• 1999

Typhoons were known by contributing to transporting plus heat or kinetic energy from equatorial region to midlatitude region. Due to the strong damage from typhoon, we acknowledged the theoretical study and the importance of accurate forecast about typhoon. In this study, typhoon forecasting system was developed to search the tracks of past typhoons or to display similar track of past typhoon in comparison with the path of current forecasting typhoon. It was programmed using Interactive Data Language(IDL), which was a complete computing environment for the interactive analysis and visualization of data. Typhoon forecasting system was also included satellite image and auxiliary chart. IR, Water Vapor, Visible satellite images helped users analyze an accurate forecast of typhoon. They were further refined the procedures for generating water vapor winds and gave an initial indication of their utility for numerical weather prediction(NWP), in particular for typhoon track forecasting where they could provide important information. They were also available for its utility in typhoon tracer or intensity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.525-526
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• 2006

Recently, much research has been done and many improvements have been developed for islanding protection of distributed generation(DG). Anti-islanding protection for DG must be act very quickly to prevent equipment damage at the time of disconnection and for the safety of maintenance and repair personnel. DG-based detection methods have included both passive and active types, and now research has shifted towards new anti-islanding detection methods that make up for the defects of the previous types. Because differences occur between the utility grid and the DG when connecting and disconnecting depending on the phase difference, voltage, current, relative capacity of electric power, and system operation characteristics, voltage phase angle is an important consideration. In this paper, we simulated islanded operation characteristics comparing phase difference of DG and the connected utility grid, and analyzed various parameters (real power, reactive power, RMS voltage, RMS current, power factor angle, and frequency) by varying the DG's voltage phase angle. Using this information, we propose a suitable DG voltage phase angle for enhanced passive islanding detection techniques.

• 가정과삶의질연구
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• 제17권2호
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• pp.1-18
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• 1999

The purpose of this study was to evaluate the utility of the community welfare center. for the purpose this study consisted of three main subjects(1) A analysis about the programs of the community welfare center (2) A analysis about the experience of the user and non-user on the community welfare center (3) A analysis about the demand for family welfare service program For the data set 398 married women living in Jeonju were chosen. The data were analyzed with the spss pc+ program. The major findings were as follows : (1) The program of community welfare center consisted of child adolescent elder family a disabled person community welfare program Among contents of this program family welfare program is limited to level of individual needs (2) The wives experienced of community welfare center did not satisfied about equipment location program of community welfare program The 44.0 portion of wives not experience of community wlfare center have no plan using of community welfare center (3) The wives hoped to establish diversed subjects such as parents-child communication conjugal communication sexuality education for child child care techniques health and nutrition of family member time managememt and lesuire and consumer's rights and damage relief.

• International journal of advanced smart convergence
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• 제8권4호
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• pp.161-168
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• 2019

Traffic accidents in tunnel can lead to large traffic accidents due to narrow and dark road characteristics. Therefore, special care of the driver is required when is driving in a tunnel. However, accidents can happen at any time. In the event of an accident, a narrow road structure may lead to a second accident. Therefore, all facilities installed inside the tunnel should be allowed to minimize damage in the event of an accident. We confirmed the safety of the collision target through the action of the sedan, Sport Utility Vehicle (SUV) and truck when the vehicle crashed into a stairway installed on the tunnel emergency escape route, and when a concrete barrier or guard rail was installed in front of the stairway. The behavior of the vehicle has resulted in a total of three results: rollover or rollover, change of speed and angle of the vehicle after collision. The sedan and SUV were the most secure when colliding with the guardrail, but considering the truck as a whole, concrete barriers were judged to be the most suitable for minimizing damage from the first accident and reducing the risk of the second accident.

• 한국도로학회논문집
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• 제17권2호
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• pp.135-141
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• 2015

PURPOSES : While driving, drivers are usually limited in communicating with others except for using the horn. Excessive use of the horn may cause noise pollution, quarrels between drivers and pedestrians, damage, etc. This study developed a methodology for environmental adaptation and improvements of vehicle horns. METHODS: In this study, we performed a literature review of previous studies and related technologies regarding the overuse and damage of the horn. The proposed methodology employed the paired comparison method, as well as the semantic differential method. These methods can consider various vehicle horns, such as the Sport Utility Vehicle(SUV) Horn, Van Horn, and Buzzer. In addition, we conducted a factor analysis in order to provide a direction for improvement of future horns. This research provides a means of complimenting existing intellectual property related to vehicle horns. RESULTS: As a result, the most preferred of the selected horns were the Buzzer at 86.7%. In addition, based on the factor analysis, the horns could be classified into pleasantness and comfort factors. The results indicate a positive reaction for various vehicle horns. The horn type and size of the process control have been properly developed considering the position of the vehicle and the surrounding noise measurements. CONCLUSIONS : Based on the proposed methodology, public and private sectors can use fundamental data for reasonable traffic-noise control policies.