• 한국건축시공학회지
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• 제21권6호
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• pp.629-640
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• 2021

2018년 국토교통부 통계에 따르면 재건축 연한이 도래한 주거용 건축물은 2018년 기준 약 37%에 달한다, 해체물량의 증가는 해체산업의 성장과 함께 환경 및 안전사고 등 많은 부작용을 일으키고 있다. 이에 본 연구는 해체공법 선정에 있어 안전성, 경제성, 환경성 등을 종합적으로 고려하여 현장 적용에 가장 적합한 공법 의사결정 방법을 제시하고, 특히 해체공사의 안전성을 고려하여 현장 공법 적용 시 위험요인에 대한 사전평가를 통해 공법선정뿐만 아니라 선정 공법의 현장 적용성을 평가한다. 이를 위해 본 연구는 QFD 기반의 TOPSIS 해체공법선정과 FMEA 위험성평가 통합모델을 제안한다.

• 보건의료산업학회지
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• 제7권3호
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• pp.203-212
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• 2013

Medical devices separated by a committee of the International Electrotechnical Commission IEC TC (Technical Committee) 62 medical electrical equipment being promoted by the International standards. Actually, a lot of standards were existed, but many national and international standards for medical devices were lacking in practical standards that can be applied to their development. Most international standards were focused in electrical and mechanical safety of medical devices. Therefore, there were few practical standards which contain essential performance evaluation. Although medical device regulations do not enforce a fixed lifecycle model, activities are presented in a sequential manner, thus hinting at a waterfall process. Meanwhile, for a decade or more, software teams have benefitted from agile development methods. Several medical device manufacturers have adopted agile practices while keeping development in compliance with regulations, but conflicts arise and decisions have to be taken in favor of agility or formality. However, if there are new practical standards of medical devices, it must be possible to promote the medical devices industry in their nation. To do this, there is a need to develop a new standard could apply to the international market through the analysis of the medical device related technology. Consequently, new standards such as NP (New proposal) or NWIP (New Work Item Proposal) should be developed through international standardization of medical device technology.

• 농촌지도와개발
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• 제14권2호
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• pp.301-328
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• 2007

The purposes of this study were to classify the silver farming types and to investigate proper crops for silver farmers. Data were collected from 408 farmers returned from the urban area. Descriptive statistics were employed using SPSS/PC windows program. After then, researchers discussed the silver farming patterns and their proper crops, and tried to analyze the silver farming model. Major results were as follows: The farming aims of retirees, urban residents as well as farmers returned from the urban area were various from hobby/ leisure to income generating activities. Fourteen types of silver farming were classified by farming aim and residential area of retirees. Retirees in the hobby/leisure-oriented silver farming type can select and enjoy the various plants, animals, and insects as well as crops due to their small scale. Silver farmers in the self-sufficiency type may select crops for their food. Income-oriented silver farmers may have difficulties in choosing the proper crop. They must consider their income needs, health status and field location. Profit-oriented silver farmers with venture mind can have some business opportunities in the agricultural sectors in spite of severe competition. As the aged silver farmers have poor health, they must keep work safety rules, use the proper work-aids, and utilize the labor-saving farming system.

• Nuclear Engineering and Technology
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• 제28권6호
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• pp.507-521
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• 1996

Quantification of uncertainties in the source term estimations by a large computer code, such as MELCOR and MAAP, is an essential process of the current Probabilistic safety assessment. The main objective of the present study is to investigate the applicability of a combined procedure of the response surface method (RSM) based on input determined from a statistical design and the Latin hypercube sampling (LHS) technique for the uncertainty analysis of CsI release fractions under a Hypothetical severe accident sequence of a station blackout at Younggwang nuclear power plant using MAAP3. OB code as a benchmark problem. On the basis of the results obtained in the present work, the RSM is recommended to be used as a principal tool for an overall uncertainty analysis in source term quantifications, while using the LHS in the calculations of standardized regression coefficients (SRC) and standardized rank regression coefficient (SRRC) to determine the subset of the most important input parameters in the final screening step and to check the cumulative distribution functions obtained by RSM. Verification of the response surface model for its sufficient accuracy is a prerequisite for the reliability of the final results that can be obtained by the combined procedure proposed in the present work.

• International Journal of Naval Architecture and Ocean Engineering
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• 제9권5호
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• pp.568-576
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• 2017

With an increase in the usage of LNG, there is a heightened interest about its safety aspects regarding the explosion of LNG carrier tank. The need for a cryogenic explosion-proof camera has increased. The camera has to work in cryogenic environment (below $-160^{\circ}C$) in LNG carrier. This study conducted design and heat transfer analysis of cryogenic camera to secure working time in limitation of heat source. The design with gap width of double pane windows was conducted based on simple vertical cavity model to insulate from cryogenic environment. The optimal gap width was 12.5 mm. For effective analysis considering convection within the camera, equivalent thermal conductivity method was adopted with ABAQUS. The working time of the camera predicted was over 10 h at warm-start condition. In cold-start condition, it required about 5 h of pre-warming time to work. The results of analysis were compared with the ones of the actual cryogenic test.

• 대한산업공학회지
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• 제25권2호
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• pp.266-273
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• 1999

The maximum work capacity at various shoulder angles was estimated in terms of joint moment through maximum voluntary contraction (MVC) measurement, and the result was compared to workload computed from 3-D static lifting model (3DSSPP) based upon national institute of safety and health (NIOSH) lifting guideline (1991). The electromyography (EMG) of anterior/posterior deltoid and trapezius muscle was also recorded to study the function of individual muscle during asymmetric shoulder lifting. Psychophysical workload was measured to observe the difference from MVC or biomechanical estimation. An apparatus was constructed for the study and twenty five trials including five flexion angles and five add/abduction angles were performed isometrically. Results indicated that MVC at 30 degree of flexion was the strongest whereas MVC at 120 degree was the weakest. In case of add/abduction, MVC decreased to 77 to 89 % during add/abduction compared to the MVC at neutral position. Regarding the normalized EMG value, a substantial increase was observed at 30 and 60 degree abduction. More importantly, the shoulder moment computed from maximum permissible limit (MPL) was greater than the moment at MVC condition during 30 degree adduction. Current result can be used as a reference information for a safe workplace design to prevent the shoulder from an excessive work load in industry.

• Industrial Engineering and Management Systems
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• 제13권2호
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• pp.203-209
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• 2014

This research designed and implemented a supply chain risk management platform and applied it to a case study of reduced-fat Lanna pork sausage as a new product development project. The proposed framework has three stages: risk identification, risk assessment, and risk mitigation. Seventeen risk agents with 17 risk events were identified based on SWOT analysis and the Porter Five Forces concept through the process of planning, sourcing, making and delivering, partially captured from the supply chain operations reference model in the first stage. In the second stage, an house of risk (HOR) framework was applied to present the impacts of each risk agent. In the third stage, eight risk agents with high impact were selected to design 21 preventive actions. Finally, three preventive actions with the highest effectiveness to difficulty ratio scores-'sales evaluation of familiar products', 'increasing distribution channels and promotions to improve sales', and 'work flow improvement for work safety'-were then recommended for this new product development.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.1-6
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• 2013

Concrete construction requires utilization of many temporary facilities such as formwork, shoring, and scaffolding. Appropriate use of these temporary facilities greatly impacts the quality, cost, schedule, and safety of concrete construction. The current practice in design and planning of temporary facilities is often manual, error-prone, and re-active based on construction site layout, status, and progress in the field. Early design and planning of temporary facilities for concrete construction using Building Information Modeling (BIM) technology offers a potential solution. Although some commercially-available software exists that assists in the generation of temporary facility designs, the construction industry lacks tools that support detailed planning and design of many other temporary facilities. This research presents our early work in automating the design and planning of temporary facilities utilizing BIM. Algorithms were developed to automatically assess geometric conditions of work space to detect required temporary facilities and design them. The proposed methodology was implemented in a test model. By automatically incorporating temporary facilities into BIM, more realistic construction models can be created with less effort and errors. Temporary facilities-loaded models can finally be used for communication, bill of materials, scheduling, etc. and as a benchmark for field installation of temporary formwork, shoring, and scaffolding systems.

• Nuclear Engineering and Technology
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• 제56권3호
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• pp.1052-1065
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• 2024

Advanced Pressurized Water Reactors (APWRs) and Boiling Water Reactors (BWRs) employ a suppression pool as a heat sink to prevent containment overpressure. Steam can be discharged into the pool through multi-hole spargers or blowdown pipes in both normal and accident conditions. Direct Contact Condensation (DCC) creates sources of momentum and heat. The competition between these two sources determines the development of thermal stratification or mixing of the pool. Thermal stratification is of safety concern as it reduces the cooling capability compared to a completely mixed pool condition. In this work we develop a scaling approach to prediction of the thermal stratification in a water pool induced by steam injection through spargers. Experimental data obtained from large-scale pool tests conducted in the PPOOLEX and PANDA facilities, as well as simulation results obtained using validated codes are used to develop the scaling. Two injection orientations, namely radial injection through multi-hole Sparger Head (SH) and vertical injection through Load Reduction Ring (LRR), are considered. We show that the erosion rate of the cold layer can be estimated using the Richardson number. In this work, scaling laws are proposed to estimate both the (i) transient erosion velocity and (ii) the stable position of the thermocline. These scaling laws are then implemented into a 1D model to simulate the thermal behavior of the pool during steam injection through the sparger.

• 한국건축시공학회지
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• 제19권4호
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• pp.361-371
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• 2019

2017년 전체 산업에서 건설업의 재해자와 사망자의 비중은 각각 25.2%, 29.6%로 가장 높은 실정이다. 특히 건축 현장의 안전사고가 지속적으로 증가하고 있어 경제적 손실이 매우 크다. 따라서 본 연구는 건축공사의 안전사고를 예방하기 위하여 공종별 안전위험도 평가지수를 개발하였고, 그 주요 연구결과는 아래와 같다. 첫째, 건축공사 현장의 안전사고와 관련된 위험요인을 설문조사와 면담조사를 통하여 17개 요인을 도출하여, 전문가 자문회의를 걸쳐 9개 항목(공종, 공사종류, 공정율, 계약금액, 층수, 공사기간, 안전교육, 현장근무일수, 날씨)을 제안하였다. 둘째, 건설현장의 안전사고 위험도 평가지수는 안전사고의 발생 비율과 발생강도를 토대로 공종별 평가지수 산정모델을 개발하였다. 셋째, 본 연구는 위험도 평가지수 평가모델을 검증하기 위하여 건설재해사고 통계자료를 조사 및 분석하여, 공종별 건설안전 위험 평가지수를 도출하였다. 또한 본 연구에서는 건설안전사고로 인한 인적손해를 사망자와 부상자로 구분하여 위험강도를 산출하였다. 공종별 안전사고 발생빈도와 발생강도에 따른 위험평가지수와 도출된 위험요인은 향후 건설안전 위험도 예측시스템 개발시 기초자료로 활용될 수 있을 것으로 기대된다.