• International Journal of Air-Conditioning and Refrigeration
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• 제17권2호
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• pp.45-51
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• 2009

Three-dimensional numerical analyses of mechanical ventilation system in vent shaft of subway in operation are carried out in relation with the different air flow passage of vent shaft and two ventilation operation modes of push/pull, The ventilation characteristics of vent shaft with regard to the shape change are evaluated. And the air flow rate through the vent shaft by ventilation system is measured within subway in operation to assess the accuracy and applicability of the numerical analysis method. The decrease of air flow rate due to vent-shaft change are between 0.7 to 2.2% in the cases examined.

• 시스템엔지니어링학술지
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• 제19권1호
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• pp.39-43
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• 2023

In ground weapon systems, the design and analysis technology for water operation stability is a relatively unknown area compared to maritime weapon systems. Through this study, it was confirmed that our weapon system satisfies the criteria for stability on the water when considering the operational concept and operational performance. However, there is a limitation of the study that it did not perform verification tests on the actual system. Therefore, in the future research and weapon system acquisition process, a procedure to prove the stability through freeboard analysis using the actual system is required.

• 상하수도학회지
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• 제24권6호
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• pp.743-751
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• 2010

It requires an interim performance assessment for BTL business of the sewerage rehabilitation which continues from 2005 till now. Means, It is necessary to make an interim performance assessment and an analysis of an business effect of the sewerage rehabilitation BTL projects which still continues, and we presented an improvement method of the new sewerage rehabilitation project in future. This paper has conducted an analysis of the business effect for 3 local government BTL projects which are completed and under operation as of now in Jincheon-Gun, Cheongju-Si and Gangjin-Gun. As a method of business effect analysis, we conducted a business effect of the 3 places using the index set which we previously set for the business effect analysis. The index set in this research was sectionalized to an improvement effect of operating wastewater treatment plant, an benefit effect of the direct cost, an benefit effect of the indirect cost and an environment friendly effect. We, in this paper, conducted an business effect analysis for 3 sewerage rehabilitation BTL projects which are completed or under operation recently as a demonstration, however we judge that an business effect analysis shall be conducted in a stage that a significant time for operation has passed since the completion of the construction in order to induce an actual business effect of the sewerage rehabilitation BTL project.

• 정보처리학회논문지D
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• 제17D권6호
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• pp.443-452
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• 2010

COTS(Commercial Off The Shelf) 시스템은 점점 더 재사용 개발에 있어서 중요한 일중의 하나로 되어가고 있다. 그것은 개발될 소프트웨어 품질 혹은 프로젝트 일정에 영향을 미칠 수 있는 COTS의 신뢰성을 포함한다. COTS 분석의 결과가 생길 수 있는 위험의 결과와 함께 프로젝트에 문서화되어야 한다. 효율적인 위험관리는 문제에 쉽게 대처할 수 있게 해주며, 그것이 수용할 수 없는 예산이나 일정 지연이 되지 않도록 해준다. 본 연구에서는 COTS 개발 시, 프로세스 이정표와 노력에 관한 위험요소 분석에 대한 기준을 제시한다.

• 한국터널지하공간학회 논문집
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• 제10권4호
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• pp.361-369
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• 2008

지중터널은 대부분 지하수위 하부에 위치하므로 지하수 처리문제는 터널의 장기운영에 있어 매우 중요하다. 배수형터널의 경우 수리기능이 원활하면 라이닝에 수압이 작용하지 않으나 장기 운영으로 인해 배수시스템의 열화가 진행되면서 라이닝 배면에 설계 시 고려하지 않았던 간극수압이 작용하게 되는데, 이를 잔류수압이라 한다. 잔류수압은 피에조미터로 그 측정이 가능하나 이는 라이닝 및 배수시스템을 훼손할 염려가 있어 부적합하기 때문에 라이닝을 손상시키지 않으면서 작용수압을 평가할 수 있고, 운영 중 라이닝의 건전도 평가(health monitoring) 시 수압상태의 파악이 가능한 비파피 예측기법이 요구된다. 본 논문에서는 이론적 및 수치해석적 방법을 사용하여 운영 중 터널에 작용하는 간극구압(잔류수압) 예측기법을 제시하였으며, 본 해석방법을 이용하면 비파괴 방법으로 라이닝에 작용하는 간극수압의 파악이 가능하다. 제안된 방법은 이론적 예측기법과 수치해석 결과인 정규화 간극수압 분포곡선과를 병용함으로써 터널 운영단계에서의 잔류수압에 대한 안정성 검토에 유용하게 활용될 수 있다.

• 한국산림과학회지
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• 제104권2호
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• pp.230-238
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• 2015

현재 우리나라의 주요 임업기계에 의한 임목수확작업시스템에서 벌목 및 조재, 집재, 소운재, 파쇄 등의 목재생산 및 파쇄작업에 대한 작업비용을 분석하여, 산림바이오매스 이용을 위한 효율적인 임목수확작업시스템을 구축하기 위한 기초자료를 제공하고자 수행하였다. 임목수확작업시스템의 작업비용을 분석한 결과, 체인톱에 의한 벌목 및 조재와 타워야더에 의한 집재, 임내작업차에 의한 소운재, 트럭에 의한 운재작업으로 이루어진 임목수확작업시스템 D가 63,482원/$m^3$으로 가장 적은 비용이 소요되는 것으로 나타났다. 또한, 산림바이오매스 이용을 위한 작업시스템의 작업비용을 분석한 결과, 소형 목재파쇄기에 의한 현장파쇄, 임내작업차에 의한 칩 소운반, 트럭에 의한 칩 운반작업의 작업시스템 E가 90,770원/ton으로 가장 적은 비용이 산출되었다. 따라서, 이들의 결과가 임목수확작업 및 산림바이오매스 이용을 위한 효율적인 작업시스템이라고 판단된다.

• 스마트미디어저널
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• 제5권1호
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• pp.95-103
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• 2016

본 연구는 우리나라 디자인컨설팅기업의 운영현황을 미국의 디자인컨설팅기업의 운영현황과 비교해 보고 향후 디자인컨설팅 산업이 질적인 성장을 이루기 위한 방안들을 모색해 보기 위한 목적으로 수행되었다. 분석을 위해 우리나라 109개 디자인컨설팅기업과 미국의 97개 디자인컨설팅기업을 대상으로 디자인컨설팅기업의 운영특성에 대한 설문조사를 수행하였으며, 수집된 자료에 대한 비교분석을 수행하였다. 분석결과 디자인컨설팅기업의 운영특성인 클라이언트기업과의 장기적인 파트너쉽 관계형성, 다학제적 조직구성, 결과중심의 보상체계 운영, 클라이언트기업의 전략적 수준에서의 디자인컨설팅서비스 제공, 능동적인 디자인비즈니스의 실행, 기업간의 융합 네트워킹, 디자인서비스의 전문화 등 7가지 분야에 있어서 한국의 디자인컨설팅기업이 미국의 디자인컨설팅기업에 비해 전반적으로 낮은 수준으로 유지하고 있는 것으로 나타났다. 향후 우리나라의 디자인컨설팅산업이 질적 성장을 거두고 안정적인 산업구조를 이루기 위해 7개 분야의 운영특성에 대한 지속적인 노력이 요구된다고 할 수 있다.

• Geomechanics and Engineering
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• 제37권1호
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• pp.9-19
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• 2024

This study presents an energy analysis for large-strain cavity expansion problem based on the general strength criterion and energy theory. This study focuses on the energy dissipation problem during the cavity expansion process, dividing the soil mass around the cavity into an elastic region and a plastic region. Assuming compliance with the small deformation theory in the elastic region and the large deformation theory in the plastic region, combined with the general strength criterion of soil mass and energy theory, the energy dissipation solution for cavity expansion problem is derived. Firstly, from an energy perspective, the process of cavity expansion in soil mass is described as an energy conversion process. The energy dissipation mechanism is introduced into the traditional analysis of cavity expansion, and a general analytical solution for cavity expansion related to energy is derived. Subsequently, based on this general analytical solution of cavity expansion, the influence of different strength criterion, large-strain, expansion radius, cavity shape and characteristics of soil mass on the stress distribution, displacement field and energy evolution around the cavity is studied. Finally, the effectiveness and reliability of theoretical solution is verified by comparing the results of typical pressure-expansion curves with existing literature algorithms. The results indicate that different strength criterion have a relatively small impact on the displacement and strain field around the cavity, but a significant impact on the stress distribution and energy evolution around the cavity.

• Archives of Plastic Surgery
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• 제36권3호
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• pp.262-268
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• 2009

Purpose: Recently medical dispute about plastic surgery is increasing rapidly as result of growing surgery itself due to high interest in appearance and advertisement of plastic surgery. So we want to find a way to prevent similar medical accident by making better solution of plastic surgery through case analysis of medical dispute. Method: 161 cases about plastic surgery asked for aid at Korea Consumer Agency and 41 cases judged at the court was surveyed and gender, location and kind of hospital, goal and kind of operation, making operation agreement or not, kind of damage, result of process, result of lawsuit was studied from 2004.1.1. to 2006.12.31. Result: Medical doctor have to explain about symptoms of disease, method of treatment, possibility of complication, prognosis to patients before therapy so they can make decision if they take operation by doctor or not. On this survey, among the patients who underwent re - operation or had complication, 88.1%(96 from 109 cases) of them didn't get enough explanation about possibility of complication before surgery They brought lawsuit insisting they would not undergo operation if they got enough explanation about possibility of complication and result of operation before surgery. Conclusion: It is advisable that doctor must observe the duty of explanation before surgery and respect the right to decide of patient, make operation agreement and put down concrete progress note and store the pre and post operative photo to avoid medical accident. It is also needed to have guideline of therapy, Code of ethics, organization which deals with medical dispute, reconsideration of law to control that.

• 한국유체기계학회 논문집
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• 제18권4호
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• pp.30-35
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• 2015

This study analyzed the variations in the performance and operation of a 200 kW class micro gas turbine according to performance degradation of compressor and turbine. An in-house code, developed by the present authors and presented in the first part of these series of papers, were used for the analysis. The degradation of compressor and turbine were simulated by modifications in the their performance maps: mass flow rate, pressure ratio and efficiency were decreased from the reference values. Firstly, the variations in the operating conditions (air flow rate, pressure ratio) were predicted for the full load condition. Then, the same analysis were performed for a wide partial load operating range. The change in engine's performance (power output and efficiency) due to the component degradation was predicted. In addition, the change in the compressor surge margin, which is an important indicator for safe engine operation, was evaluated.