• 상하수도학회지
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• 제25권6호
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• pp.885-892
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• 2011

In this study, LCA(Life Cycle Assessment) on 'Saemangum CSO Project' was carried out to evaluate environmental impact which occurred during the construction and operation periods and the potential environmental impact reduction was analyzed by comparing production and reduction level of pollution loads. LCA was conducted out according to the procedure of ISO14040 which suggested Goal and Scope Definition, Life Cycle Inventory Analysis, Life Cycle Impact Assessment and Interpretation. In the Goal and Scope Definition, the functional unit was 1 m3 of CSO, the system boundary was construction and operation phases, and the operation period was 20 years. For the data collection and inventory analysis, input energies and materials from civil, architecture, mechanical and electric fields are collected from design sheet but the landscape architecture field is excepted. LCIA(Life Cycle Impact Assessment) was performed following the procedure of Eco-Labelling Type III under 6 categories which were resource depletion, eutrophication, global warming, ozone-layer destruction, and photochemical oxide formation. In the result of LCA, 83.4% of environmental impact occurred in the construction phase and 16.6% in the operation phase. Especially 78% of environmental impact occurred in civil works. The Global warming category showed the highest contribution level in the environmental impact categories. For the analysis on potential environmental impact reduction, the reduction and increased of environmental impact which occurred on construction and operation phases were compared. In the case of considering only the operation phase, the result of the comparison showed that 78% of environmental impact is reduced. On the other hand, when considering both the construction and operation phases, 50% of environmental impact is increase. Therefore, this study showed that eco-friendly material and construction method should be used for reduction of environmental impact during life cycle, and it is strongly necessary to develop technology and skills to reduce environmental impact such as renewable energies.

• 한국콘텐츠학회논문지
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• 제20권12호
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• pp.287-300
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• 2020

본 연구는 노인복지관이 운영하는 실버 오케스트라 프로그램의 실천적 개선 방향을 도출하기 위하여 운영 속성에 대한 중요도-만족도 분석(IPA)을 수행하였다. 우리나라의 춘천동부노인복지관이 운영하는 '춘천 실버 오케스트라' 프로그램을 대상으로 실버회원 그룹(N=53)과 프로그램 운영자 그룹(N=32)을 조사 대상자로 선정하였다. '지역사회와의 연계', '예산 운영', '프로그램 운영', '인력 운영', '홍보전략', '프로그램 운영환경'을 포함하는 6개의 평가영역으로 구성된 평가지표를 설계하였다. 그리고 평가영역에 대하여 22개의 평가항목을 구성하였다. 본 연구의 결과, 실버회원 그룹에서는 '인력 운영'이 중요도와 만족도에서 가장 높은 우선순위를 가지는 것으로 나타났다. 프로그램 운영자 그룹에서는 '예산 운영'과 '인력 운영'이 중요도와 만족도에서 각각 가장 높은 우선순위를 차지하였다. IPA 매트릭스 분석을 통하여 나타난 연구 결과를 기반으로, 성공적인 프로그램 운영을 위해서는 실버회원 그룹과 프로그램 운영자 그룹의 관점에서 현상유지 및 강화, 집중투자 및 개선, 낮은 우선순위, 그리고 과잉노력 지양으로 영역화된 프로그램 운영 속성에 대해서 서로 차별화된 노력과 관심을 지속적으로 가져야 한다는 시사점을 제공한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.199-204
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• 2000

A low temperature differential model stirling engine is manufactured, and its operation characteristics are measured and analyzed by SIMPLE analysis model, in which heat transfer processes are simply considered. The heat transfer coefficients between working fluid and heat sources in the analysis are estimated by comparing the P-V diagrams by experiment and by analysis. This result may be very useful for further design and manufacture of model Stilting engines as well as real engines because it provides a comparatively correct predictions of the operation conditions and power output. It will be also conveniently used as an educational material for mechanical engineering students because it can be a nice example of optimal design process to decide the phase angle and compression ratio of engine design with a simple but realistic simulation.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.381-385
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• 2006

This research introduces easy tool manufacturing method regarding tool manufacturing procedure. In the conventional method, wire cutting machining and lapping operation of corner and render region were performed after shrink-fitting to ensure the accuracy of gear profile. But lapping operation is very difficult due to corner and render is located deep inside of die. In this research, wire cutting operation was performed after $1^{st}$ ring was shrink-fitted to ease lapping operation and increase the accuracy of corner radius. Before $2^{nd}$ ring fitting, lapping was completed. Elastic deformation amount due to $2^{nd}$ ring fitting and cold forging was calculated through finite element analysis and wire cutting specification was offset in that amount. Comparison of gear dimension between analysis and forged part ensures the validity of new manufacturing methods.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.636-641
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• 1998

In this paper, operation characteristics of the Zero-voltage-Switching(ZVS) mode and Non-Zero-Voltage-Switching (NZVS) mode of the active clamp (ACL) forward converter are compared through the loss analysis. The losses of semiconductor devices, transformer and passive elements of the converter are analyzed and compared for each type of operation mode. In order to verify the validity of the analysis, we have built a 50W ACL forward converter and measured the losses of the converter. From the experiment it is known that the ACL forward converter shows nearly same loss distribution for both of operation modes

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.173-175
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• 2013

In tall building construction, the equipment operation plans have an effect on productivity. Equipment, used in tall building construction, has operating plans of each it and restrictively operate owing to the first placed equipment operation. Therefore the interference of equipment was occur frequently. As it, the productivity is less effective and the construction delay occurs. This research was analysis the interference elements between the equipment for constructing the efficient equipment associated operational processes. The interference elements between the equipment derive through expert advice and analysis using IPA. Through the IPA, this research deducted the interference elements located 'Concentrate Here' which is the highest importance and the lowest performance.

• 전기학회논문지P
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• 제57권4호
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• pp.383-387
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• 2008

This paper analyzes the operation characteristics of a self excited induction generator with Steinmetz connection. For this analysis, the symmetrical components analysis is used to obtain the related expressions and the excitation capacitance and the magnetizing reactance are determined in turn by the condition of self excitation which includes the input impedance of the generator as viewed across load terminals. Two simultaneous equations of the condition of self excitation itself are solved by using the real and imaginary function in an application software. This method is applied to simulate the operation characteristics when the generator is driven at rated speed and the specified excitation capacitor is connected across the lagging phase. The results show that better operation characteristics except generated frequency are obtained by using relatively large excitation capacitance and resistive load.

• 한국항만경제학회지
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• 제28권3호
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• pp.151-165
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• 2012

우리나라 무역항만은 국제물류의 99% 이상을 처리하는 물류거점으로서 국가 경제에 중요한 역할을 수행한다. 최근 선박의 초대형화와 각종 항만 장비의 고도화에 따라 항만의 생산성을 높이기 위한 연구는 활발히 진행되고 있지만, 항만안전운영에 대한 관심은 상대적으로 도외시 되고 있는 있다. 2010년 기준, 항만하역업 재해율은 0.98로 전 산업 평균인 0.69보다 40%이상 높게 나타남에 따라 항만안전운영에 관한 체계적인 교육 방안을 마련할 필요성이 제기되고 있다. 본 연구에서는 데이컴 기법을 활용하여 항만안전운영에 관해 직무분석을 수행하여 직무모형을 개발하였다. 항만안전운영 직무분석 결과 총 8개의 임무와 각 임무를 구성하는 59개의 세부 작업을 도출하였다. 그리고 교육 요구도를 조사하기 위하여 각 작업에 대해 중요도와 난이도 및 수행 빈도를 조사하고 항만안전운영 분야의 기초 작업을 분석하였다. 또한 이러한 직무분석 결과를 구조화 하여 데이컴 리서치 차트를 완성함으로써 항만안전운영 분야의 직무모형을 제시하였다. 이러한 직무모형을 통해 항만안전운영에서 요구하는 직무와 수행되는 진행과정을 한눈에 파악할 수 있고, 항만안전운영 분야의 단기 교육과정과 정식교육과정 및 임무별 교육과정을 개발하는데 기초 자료로 활용될 수 있다. 본 연구는 항만안전에 관한 운영 범위가 지나치게 광범위하여 항만과 관련 업종에 종사하는 관리자 및 실무자 전체를 대상으로 설문조사를 실시하지 못하여 일반화하는데 한계가 있을 수 있다. 따라서 차후 연구에서는 항만안전 분야의 현장실무자와 관리자를 대상으로 한 인터뷰와 설문조사 등 보다 포괄적이고 구체적인 실증분석을 수행할 필요가 있다.

• 상하수도학회지
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• 제34권6호
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• pp.495-502
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• 2020

The 37 indicators for performance evaluation of public sewage management agencies are divided into four major categories (agency manpower management ability, wastewater treatment plant operation and management, sludge and water reuse, service quality) in the first stage, and the necessity and score acquisition for the detailed indicators by each major category in the second stages. Priority was investigated through the Analytic Hierarchy Process (AHP) analysis technique for ease and relevance of company efforts. Also, based on the results of this analysis, integrated type weighting and relative importance were analyzed. As a result of the analysis, the weight and relative importance of the first stage classification were in the order of wastewater treatment plant operation and maintenance, operation agency manpower management ability, sludge and water reuse, and service quality. As a result of analyzing the weights and priorities of the detailed performance indicators in the second stage, it was found that operator's career years, the percentage of certification holding rate in operators, compliance with the effluent water quality standards, training times for operators, and efforts to manage hazardous chemicals were important. Some of the indicators of operation agency performance evaluation may include indicators in which the performance of the company's efforts is underestimated or overestimated. In order to improve this, it is necessary to give weights in consideration of the necessity of the indicator, the relevance of the company's efforts, and the ease of obtaining scores.

• 한국수학교육학회지시리즈A:수학교육
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• 제59권2호
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• pp.167-183
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• 2020

본 연구는 중학교 수학과 교육과정의 수와 연산 영역의 시대적 변천 과정을 분석하고, 그 결과를 바탕으로 수와 연산 영역에서 수학 학습내용의 재구조화 방향 제시를 위한 문헌 연구이다. 이를 위해 1차 중학교 수학과 교육과정부터 2015개정 중학교 수학과 교육과정까지 제시된 수와 연산 영역의 내용을 고찰하였고, 이를 바탕으로 수와 연산 영역의 수학 학습내용에 대한 분석을 실시하였다. 먼저 비교 분석의 기준을 3차 중학교 수학과 교육과정으로 설정하였고, 분석을 위한 수학 학습내용으로 내용요소와 학습요소로 세분화하여 기본 분석틀을 개발하였다. 최종적으로는 이러한 기본 분석틀을 기초로 수와 연산 영역의 핵심 이슈가 되는 수학 학습내용을 추출하여, 추출된 수학 학습내용에 대해 세계 여러 나라 교육과정에서 다루고 있는 현황을 비교 분석하였다. 최종적으로 본 연구를 통해 중학교 수와 연산 영역에 대한 새로운 교육과정 개발에 유의미한 재구조화 방향을 제시하였다. 본 연구의 결과가 새로운 교육과정 개발의 토대가 될 것으로 기대된다.