• 한국기계기술학회지
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• 제13권3호
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• pp.119-124
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• 2011

Electric night storage heater was introduced and disseminated for power grid balancing and efficient management of power generation facility. But fuel cost for heating has been increased rapidly while the cost of electricity increased slightly. This abnormal rate system caused peak load in winter at last. To solve this problem, application of an air source heat pump was suggested. In the study, the effect of replacing night heater by heat pump and the economics were analysed. In addition the expectation of prospect of heat pump penetration was simulated based on surveyed and investigated data. As a result, fund supporting as well as institutional backing was needed for effective propagation and return of investment.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.440-448
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• 2009

Concurrent construction (or overlapping) is an alternative project delivery process to reduce time-tomarket such that the owner can get higher profits; the increased profits due to shortened project duration would exceed the loss of profits from the increased cost, if any. For more effective concurrent construction, a new conceptual framework for concurrent construction planning is suggested. With multiple work methods available in each activity, the performance of overlapping between two activities in terms of cost is affected by the compatibility between work methods selected and the benefit to the project owner is determined by internal rate of return (RoR). The impact of the compatibility between work methods and the conceptual framework are explained by a hypothetical case study.

• 경영과학
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• 제20권2호
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• pp.33-43
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• 2003

In this paper we applied dynamic programming to determining work schedule type. In dynamic programming formulation, each day during a planning horizon represents a stage for which a decision is made. The alternatives are given by work schedule types that combine regular time, overtime, additional shift, and so on. In this case, their associated return function is labor cost. The state is defined as the amount of work time allocated to stage 1, stage 2,…, and current stage. A case study for a real manufacturing company was performed to apply dynamic programming to scheduling daily work hours during a week. The case study showed that total cost of our solution derived from dynamic programming decreased by about 6％ as compared with the solution obtained from the previous method.

• Asian-Australasian Journal of Animal Sciences
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• 제7권3호
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• pp.421-426
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• 1994

Twelve cross bred cows ($300{\pm}20kg$) were fed a basal ration consisting of 1 kg concentrate and untreated or urea treated rice with or without urea-molasses-wheat bran lick block supplementation. The lick blocks were prepared locally using cement as a binding agent. The experiment lasted for 48 days consisting of a preliminary period of 14 days and a measurement period of 34 days. Daily dry ma tter intake (DMI) of straw and lick block, and daily milk yield were recorded during the measurement period. Intake of lick block when fed with untreated straw (US) was significantly higher (p < 0.01) than with urea treated (TS) straw (397 vs 307g $100kg^{-1}$), but lick block supplementation did not significantly affect the in take of US (1.80 vs 1.83kg $100kg^{-1}day^{-1}$) or TS (2.27 vs 2.17kg $100kg^{-1}day^{-1}$). Both urea treatment and lick block supplementation significantly increased (p < 0.01) the milk yield of cows, and the increase due to urea treatment was higher than that due to lick block supplementation. Benefit/cost ratio obtained for feeding US or TS with 1 kg dairy concentrate was similar (5.4), but the marginal return favours TS (5.4:1.0). The benefit/cost ratio for US and TS supplemented with lick block was 3.4 and 3.7. respectively, but the marginal return with US was higher than with TS (1.6:1.0 and 0.9:1.0, respectively).

• 한국시스템다이내믹스연구
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• 제8권2호
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• pp.5-23
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• 2007

According to the system dynamics model of this study, if there is a significant network effect on vehicle operating costs, it is difficult to achieve the shift to AFV even in the long term without a policy intervention because the car market is locked in to the current structure. Network effect can be caused by an increasing return to scale in fuel supply sector as well as in maintenance service sector. It is also related to the fact that the reliability and awareness of consumers on new products increases with the growth of the market share of the new products. There are several possible policy options to break the 'locked in' structure of car market, such as subsidy on vehicle price (capital cost), subsidy on fuel (operating cost) and niche management policy. Combined policy options would be more effective than relying on a single policy option to increase the market share of AFV.

• 환경정책연구
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• 제2권2호
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• pp.41-63
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• 2003

CDM(Clean Development Mechanism) project is said to be a mechanism, which profits both the investing country and the host country, while additionally contributing to the reduction of greenhouse gases of the earth as a whole. However in reality, most of the proposed projects do not end up in agreement because of the problems related to differences in recognition between the investing country and the host country of the CDM project. This outlines the background for this research which proposes a new design of institutional arrangements of CDM projects in the Northeast Asian region, mainly Japan, China and Korea. In addition, we investigate the feasibility of the proposed design. The research firstly focuses on the reduction in transaction costs that the participation of Korea will have on a Japan-China CDM project. This paper further emphasizes the potential gains that would materialize if a CDM project involved the whole Northeast Asian region, and not only one country. Our research suggests that an approximate reduction of 23% in transaction costs, and about 4% reduction in the total costs of a CDM project can be expected to follow the Korean participation. In addition to decreasing costs we find that a Korean involvement in a CDM project with Japan will lead to efficiency gains illustrated by a higher increase in the IRR(Internal rate of return) in a Japan-Korea project(11.45% to 12.21%) compared to an IRR incresement of 10.57% to 11.27% for a pure Japanese CDM project. Similar results of a rise in the IRR is found for the whole investment period of 20 years. We can hence conclude that Korean participation in a Japan-China CDM project would improve the implementation possibilities of CDM project in the Northeast Asia region.

• 한국통신학회논문지
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• 제31권7B호
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• pp.660-667
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• 2006

본 연구에서는 무선 LAN 시장의 새로운 돌파구로 기대되는 VoWLAN의 투자 수익률 분석을 위해 구체적이고 실용적인 방법론을 제시하고자 한다. 이를 위하여 먼저 국내외 VoWLAN 시장의 동향을 분석한다. 다음으로는 투자수익률 분석을 위해 구축유형에 따라 VoWLAN에의 비용항목과 VoWLAN과 경쟁하는 대안서비스(유선랜과 유선전화서비스)의 비용항목을 산정한 후 대안서버스와 비교한 VoWLAN의 혜택 항목과 투자수익률 분석 시 필요한 기타 입력항목을 선정한다. 또한, 대상 기업의 다양한 상황에 맞는 구축 시나리오를 제시하고 각 시나리오 별로 비용/혜택 분석 프레임워크에 따라 경제성 분석을 실시한다. 본 연구에서는 개발된 투자 수익률 분석 프레임워크의 유용성을 검증하기 위해 VBA 프로그램으로 구현하여 실제 사례에 적용한다.

• 한국위성정보통신학회논문지
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• 제7권1호
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• pp.13-20
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• 2012

지구환경감시 위성개발에 관한 관심이 날로 증가하고 있음에도 불구하고, 위성으로부터의 정보를 빠른 시간 내에 가공하여 활용할 수 있는 영상처리기술에 대한 투자는 미미한 실정이다. 본 논문에서는 한국형 위성영상처리 기본체계 구축에 필요한 각 요소기술과 관련 산업의 관계를 정성적으로 고찰하였으며, 시스템 구축비용을 추정하여 관련 산업이외의 산업파급효과를 정량적으로 도출하였다. 또한, 한국형 위성영상처리 기본체계 구축에 소요되는 비용과 이에 수반되는 혜택에 대한 내부수익률을 산출하여 경제적 타당성을 계량적으로 분석하였다. 분석결과, 농수산업, 관광레저산업, 운송업 등이 본 체계 개발과 관련성이 높았으며, 이로 인하여 직접관련 산업을 제외하고 91억 원의 생산유발효과, 33억 원의 부가가치유발효과, 그리고 54명의 고용유발효과가 있을 것으로 분석되었다. 한편 비관적 시나리오에서도 최저수익률 5.5%을 상회하는 7%의 수익률을 보일 것으로 예측되어 투자타당성을 확보하는 것으로 확인되었다.

• 자원리싸이클링
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• 제21권1호
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• pp.49-59
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• 2012

콩고민주공회국(Democratic Republic of Congo, 이하 DR콩고)은 세계적 자원부국으로 특히 코발트, 철광석, 구리, 다이아몬드 등이 풍부하다. 주요 광물자원의 대부분을 수입에 의존하고 있는 한국은 2008년부터 콩고정부와 한국이 항만 건설을 지원하고, 그 보상으로 루붐바시 슬래그재처리를 통해 아연, 코발트, 구리 등 유용광물을 회수해가는 프로젝트에 대한 검토를 추진하여 왔다. 본 연구는 DR콩고의 루붐바시 슬래그 재처리 사업에 대한 경제성 분석을 수행한 것으로, 연구 결과에 따르면 투자회수기간(pay back period)은 6.7년, 순현재가치(NPV) 3,400만달러, 내부수익률(IRR)은 17.4%로 나타났다. 또한 세제, 고정비용, 운영비용, 지원가격 등에 대한 불확실성을 적용한 민감도 분석 결과 프로젝트의 순현재가치는 최저 -2,480만달러에서 최대 9,270만달러로 나타났다.

• 자원ㆍ환경경제연구
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• 제18권1호
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• pp.1-22
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• 2009

ITQ 제도의 목적은 어업에 투자된 과도한 자본을 줄여 어자원의 남획을 막는데 있다. 그 동안 ITQ 제도는 가장 비용 효율적이지 못한 어선들부터 자신들의 쿼터를 처분함으로써 스스로 시장에서 퇴출하도록 하는 효과를 가져올 것으로 믿어져 왔다. 그러나 본 논문은 실물옵션 기법을 도입, 퇴출 비용에 비가역성이 존재할 경우 덜 비용 비효율적인 어선들이 먼저 퇴출 결정을 내릴 수도 있다는 것을 보여준다. 즉, 퇴출에 따르는 비용이 비용 비효율적인 정도에 비례하고 비가역적인 성격을 갖는다고 할 때, 퇴출에 지연 동기가 발생한다는 점을 반영하여, 오히려 자본이 과도하게 투자된 어선 보다 그렇지 않은 어선이 먼저 퇴출하게 될 수도 있다는 것을 보여준다. 마지막으로 본 논문이 현실적으로 제공하는 정책적인 함의 또한 기술하였다.