본 연구의 목적은 분만간격에 따른 추가 착유일수를 계산하여 불완전 Gamma모형으로 추정된 비유곡 선모수값을 통하여 추가 착유일 만큼의 산유량을 계산하고, 추가 착유에 따른 경제성을 분석하기 위함 이다. 경제성 분석을 위하여 농협중앙회 젖소개량사업소에서 진행하고 있는 유우군 능력검정사업에 참 여하고 있는 홀스타인 젖소로부터 조사한 착유기록 2,072개를 분석하였는데, 분석에 이용된 착유기록은 2010년 1월부터 2012년 12월 사이에 분만한 초산우 및 경산우로부터 자료이다. 비유곡선 모수는 Wood 모형을 적용하여, SAS 9.2 NLIN Procedure를 이용해 추정하였다. Wood 모형으로 추정한 비유곡선 함수는 초산우 및 경산우에 대해 각각 yt = 18.00t0.189e-0.00231t 및 yt = 24.73t0.181e-0.00315t로 추정되었다. 초산 우의 경우 산유량이 8,000kg 이하인 우군의 적정 분만간격은 400일 이하로 유지하는 것이 바람직하며, 8,000kg 이상인 우군은 분만간격을 400일에서 500일 사이로 유지하는 것이 바람직하다. 경산우의 경 우 산유량이 9,000kg 우군은 적정 분만간격을 400일 이하로 유지하고, 9,000kg 이상인 우군의 분만간 격은 400일에서 500일 사이로 유지하는 것이 바람직하겠으며, 11,000kg 이상의 고능력 경산우 우군의 경우 분만간격이 길어질수록 순수이익은 증가하나, 차기 임신 및 분만을 위해서는 분만간격을 450일에 서 500일 사이로 유지하는 것이 바람직하다고 할 수 있겠다.

This paper aims to analyze the economic feasibility and investigate the possibility of elastic seismic design of wind-designed highrise concentrically braced frames considering change of mechanical properties of Korean steel under the strong wind and the low seismicity in Korea. To this end, first, highrise concentrically braced frames were designed considering strong wind load. And then, analyses of the economics of them were performed. The seismic performance evaluation of wind-designed highrise buildings was conducted using the response spectrum analysis procedure. Analysis results show that it is possible to save up to approximately 90% of the amount of steel on the 10% increase in steel strength without serviceability. However, with serviceability, the design sectional area of the steel with relatively high strength tends to increment considerably because of the lateral stiffness due to reduction of the inertia moment and so on. This point might apply to limitation of the steel with high tensile yield strength.

The IRR (internal rate of return) is often used by investors for the evaluation of engineering projects. Unfortunately, it is widely known that it has serial flaws. Also, External rate of returns (ERRs) such as ARR (Average Rate of Return) or MIRR (MIRR, Modified Internal Rate of Return) do not differentiate between the real investment and the expenditure. The PRR (Productive rate of return) is faithful to the conception of the return on investment. The PRR uses the effective investment instead of the initial investment. In this paper, we examined two cases of the engineering project. the one is a traditional engineering project with financing activity, another is the project with R&D. Although the IRR has only one value, it overestimates or underestimate profitabilities of Engineering Projects. The ARR and the MARR assume that a returned cash reinvest other projects or assets instead of the project currently executing. Thus they are only one value of a project’s profitability, unlike the IRR. But the ARR does not classify into the effective investment and non-investment expenditure. It only accepts an initial expenditure as for an investment. The MIRR also fails to classify into the investment and the expenditure. It has an error of making a loss down as the investment. The IRR works as efficiently as a NPW (Net Present Worth). It clearly expresses a rate of return in respect of an investment in an engineering project with a loan. And it shows its ability in an engineering project with a R&D investment.

The Ministry of Agriculture, Forestry, Livestock and Food in Korea has done an R&D project to develop new corn and soybean varieties and cultivation technologies with Seoul National University and on-site company for three years in Russia, where Korean government has done the overseas’ agriculture for more than a decade. The objective of this study is to analyze the investment value of three years’ funding. For this, a Cost-Benefit and Scenario analysis approaches were used. The results revealed that 1) For the case of soybean, cost seems to outweigh benefits under a pessimistic scenario, but otherwise in case of neutral and optimistic scenarios. 2) The result of corn shows high economic efficiency for all scenarios. 3) The most important implication of this study is that Korea’s oversea agriculture R&D projects need to expand to different countries, regions, and crops.

For economic evaluation of integrated operation to sewage facilities, benefit-cost analysis was performed to watershed sewage works project in 7 watershed areas, 156 facilities. In this study, the cost before and after integrated operation was compared and benefits are calculated from the reduction of operators, increasement treated pollution loads, reduction cost through operation convenience, reduction water consumption through effluent reuse, and improvement of life benefit. The result showed that cost was 8,500million won and benefit was 16,747million won, so benefit was 49% higher than cost. B/C analysis result showed that B/C ratio was 1.97 and it is similar to other researches. The benefits of integrated operation included convenience of data management, increase of emergency response, decrease of complains with sewage which was not reflected numerically, so the benefits of integrated operation were expected much greater than this result.

분리막 및 다양한 CO2 포집공정들의 연구에 있어, 경제성 평가는 각 공정들을 비교 분석하며 개발된 기술의 경제적 타당성을 검토하는데 중요한 역할을 한다. 본 연구에서는 분리막 기반의 CO2 포집공정에 대한 경제성 분석을 수행하여 그 결과를 살펴보았다. 분리막 공정의 전산모사와 최적화를 위하여 분리막 모델링 및 Aspen HYSYS®를 활용하였으며, 최적화 결과를 바탕으로 CAPEX 및 OPEX를 제시하여 분리막 공정의 경제성 평가를 진행하였다.

PURPOSES : Long-life asphalt pavements are used widely in developed countries. In order to be able to devise an effective maintenance strategy for such pavements, in this study, we evaluated the performance of the long-life asphalt pavements constructed along the national highways in South Korea. Further, an economic evaluation of the long-life asphalt pavements was performed based on a life-cycle cost analysis. We aimed to devise a model for evaluating the performance of long-life asphalt pavements using the national highway pavement management system (PMS) database as well as for analyzing the economic feasibility of such pavements, in order to promote their use in South Korea. METHODS : The maintenance history and pavement performance data were obtained from the national highway PMS database. The pavement performances for a total of 292 sections of 10 lanes (5 northbound lanes and 5 eastbound lanes) of national highways were used in this study. Models to predict the performances of hot mix asphalt (HMA) and long-life asphalt pavements under two distinct traffic conditions were developed using a simple regression method. Further, the economic feasibility of long-life asphalt pavements was evaluated using the Korea Pavement Management System (KoPMS). RESULTS : We developed service-life prediction models based on the traffic volume and the equivalent of single-axle load and found that long-life asphalt pavements have service lives 50% longer than those of HMA pavements. Further, the results of the economic analysis showed that long-life asphalt pavements are superior in terms of various economic indexes, including user cost, delay cost, total cost, and user benefits, even though their maintenance cost is higher than that of HMA pavements. A comparison of the economic feasibilities of the various groups showed that group A is superior to HMA pavements in all aspects except in terms of the maintenance criterion (crack 20% or higher) as per the NPV index. However, the long-life asphalt pavements in group B were superior in terms of the maintenance criterion (crack 25% or higher) regardless of the economic feasibility. CONCLUSIONS: The service life of long-life asphalt pavements was found to be approximately 50% longer than that of HMA pavements, regardless of the traffic volume characteristics. The economic feasibility of long-life asphalt pavements was evaluated based on the KoPMS. The results of the economic analysis were the following: long-life asphalt pavements are exceptional in terms of almost all factors, such as user cost, delay cost, total cost, and user benefit; however, the exception is the maintenance cost. Further, the economic feasibility of the long-life asphalt pavements in group B was found to be better than that of the HMA pavements (crack 25% or higher).

PURPOSES: Concrete pavement has been used in the construction of the Jungbu expressway in 1987. More than 60% of the pavement on the expressway is currently made of concrete, but most has been used far beyond their design life. Pavement life has been extended through routine maintenance or overlay. However, the structural capacity of the pavement has reached its limit, and extensive rehabilitation/reconstruction with long time traffic blocking should be considered. The three following issues on concrete rehabilitation/reconstruction will be discussed: (1) economic comparison of asphalt inlay and asphalt overlay, (2) economic comparison preventive overlay on a section which is currently good and routine overlay on the section which will be poor, and (3) economic analysis of early-strength concrete when it is used in concrete reconstruction. METHODS: First, various life cycle cost analysis tools were compared, and the proper tool for the extensive rehabilitation/reconstruction was selected. Second, a sensitivity analysis of the selected tool was performed to find the influential input variables, which should be carefully selected in the analysis. Third, three case studies, which can be issues in the rehabilitation/reconstruction of the expressway concrete pavement in Korea, were performed. RESULTS: Asphalt overlay without milling the deteriorated concrete showed 18~25% lower life cycle cost than the current asphalt inlay with milling. The good current preventive overlay on the section was economically justified within the scope of this study. The construction cost limit of the early strength concrete was suggested to be economical for 1, 3, and 7 days of construction alternative opening. CONCLUSIONS: CA4PRS was a viable tool for comparing various rehabilitation/reconstruction issue alternatives. Several concrete issues associated with the rehabilitation/reconstruction of the deteriorated concrete pavement were discussed as mentioned above.

평면교차로의 원활한 운영에 대한 판단기준은 보통 서비스수준(LOS)을 따른다. 신호교차로는 신호주기 와 현시 조정 여부 등 처리효율에 따른 여러 변수에 대해서도 영향을 받겠지만, 주로 교통량이 증가할수 록 서비스수준 효과척도(MOE)인 평균지체시간이 대체로 증가하며 이는 극심한 교통정체로 이어지기도 한다. 우리나라는 교통 안전성과 효율성 확보를 위해 교차로 설계 지침서로써 전 건설교통부, 국토해양부 (현 국토교통부)는“평면교차로 설계지침”,“입체교차로 설계지침”,“회전교차로 설계지침” 등을 각각 발 간하고 도로설계 가이드라인으로 제시하고 있지만, 평면 신호교차로에서 입체교차로-주로 단순입체교차 -로 전환이 요구되는 사업 추진 시 고려해야할 기준은 명확히 제시된 바가 없다. 따라서 본 연구는 국외 입체교차로(grade separated intersection, overpass or underpass, interchange) 설계기준을 중심으 로 평면신호교차로에서 입체교차로로 전환기준에 대하여 검토, 분석하여 현 입체교차로 설계지침이 가지 고 있는 문제점 및 개선점을 도출하고자 하였다. 현 지침에서 제시하는 3가지 설계 기준은 (1) 도로 등급 과 교차형식 결정, (2) 교통량과 입체교차와의 관계, (3) 경제성을 고려한 입체교차로 구분할 수 있는데, 이 중 (2)와 (3)의 기준을 중심으로 문제점을 검토하고 이를 경기도 남양주시 삼패동에 소재한 평면신호 교차로인 삼패사거리에 적용하여 각 기준에 대한 적정성을 분석하였다. 2015년 현장 조사를 통해 수집된 교통량과 속도 자료를 기반으로 SYNCHRO와 VISSIM 활용 시뮬레이 션 분석을 실시하였는데, 먼저 교통 운영적인 측면인 교통량과의 관계에서 살펴본 결과 해당교차로는 2035년 기준 현 교차로 운영을 유지한다면 LOS가 FFF로 매우 저하되는 것으로 나타났으며, 이를 단순입 체로 전환한다면 2035년 단년 기준 감소된 평균지체시간을 비용으로 산정된 통행시간 절감편익이 총 공 사비용 및 유지비용과 대등한 것으로 나타나 입체교차로로의 전환이 시급히 요구되는 것으로 나타났다. 따라서 사례연구를 통해 입체교차로 전환기준 결정을 위한 주/부도로 교통량 관계로 보완하고, 경제성 분 석에 대한 개선안을 마련하는데 일조하고자 할 예정이다.

This paper is focused on an economic analysis of applied air pollutant control technologies used for the particulate matters present in subway. Beneficial effects such as reduction in medical expenses and prevention of productivity loss and death are achievable through the adaptation of control technologies. The result showed that the total investment expense was 97.6 billion won and the cost-benefit was 4776.8 billion won, therefore a 4.8 benefit/ cost ratio was attained.

Recently, there have been keen interests in regeneration of old industrial parks. Applying for policies and business, various indices on deterioration of inner industrial parks have been researched. However, to make regeneration projects work in actual, the condition of economic feasibility has to be met. This study focused on the economic condition of regeneration by enlarging existing indices to those of surrounding area and location as well as business environment. By applying the indices to 83 old industrial parks, which are more than 20 years old, 8 types of involvement in regeneration projects have been deduced. Among 8 types, the most frequently appeared cases were type 4 and 5, which are appropriate for regeneration and restructuring respectively.

Korea ocean research stations manage the weather and environmental data collected from coastal and ocean areas to provide short-term and long-term ocean forecasts. The purpose of this paper is to analyze and quantify economic benefits of the ocean research stations with sensors to observe physical, chemical, and biological data. The construction and operation of an integrated ocean observation station is expected to reduce uncertainty about ocean and coastal areas and to improve the quality of ocean forecasts. The economic benefits are mainly come from improved search and rescue operations, ocean pollution management, yellow dust management, and improved productivity in ocean-related industries. In addition, an input-output analysis is performed to evaluate the economic impacts of ocean research stations nationwide. The analysis shows that the system can contribute to industries such as fishing, maritime and air cargo, medical and health care.

This study analyzes performance-cost ratio of various polycarbonate(PC) pigpen. The finite element models using the ANSYS program described in this paper is attractive not only because it shows excellent accuracy in analysis but also it shows the benefit of parameter study by using APDL. We have performed various parameter study of total 6 models. And we compared and analyzed the results of 6 models. From the numerical examples, we recommend model M2. Model M2 is PC pigpen with steel in PC.

하천, 호수, 연안 양식장에서 대량 발생하는 유해미생물을 제거하기 위해 2013년 12월부터 2014년 11월 까지 스크루브러쉬 콘 필형 여과장치를 개발하여 전남 광양시 진월면 차사저수지의 현장에서 대량 발생한 미생물의 제거율을 측정 평가하였다. 아울러 개발된 장치의 경제성 및 현장 적용성의 문제점과 개선책을 제시하였다.

이 연구에서는 물량저감 철근상세를 갖는 중공 철근콘크리트 교각 시스템의 전용 설계프로그램과 소성설계 적용 결과를 제시하였다. 개발된 물량저감 철근상세는 경제성과 합리성을 갖으며 공사기간의 단축을 가져올 수 있다. 물량저감 중공 철근콘크리트 교각의 적용을 통해 경제성 평가를 수행하였다. 평가 결과 개발상세가 기존상세에 비해 구조적 합리성, 시공성, 그리고 경제성 등이 우수함을 확인하였다.