• 자원ㆍ환경경제연구
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• 제24권2호
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• pp.251-281
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• 2015

This paper examines the perceptions of sustainability, which is conceptualised as cross-generational social preferences, on the formation of international environmental agreements (IEAs) in a two-stage game in two periods. There are two scenarios are considered: myopic and sustainable development scenarios. The myopic scenario assumes the decision makers only concern the present welfare. Whilst the scenario of sustainable development has two characters: cross-generational fairness and altruism. When both are taken into account, a coalition will be expanded. The numerical example indicates that the marginal cost of the total emissions is the crucial factor for the formation of IEAs. Only when the marginal cost is low, a sustainable system can be succeeded. While, the technological advancement may lead to a more efficient production per unit of emissions, it also encourages countries to emit more in total and have a lower level of welfare. The results confirm the importance of sustainability to IEAs. The lesson learnt from this study is: when decision makers are myopic, the system is unsustainable even if an IEA is formed. Only when the perception of sustainability is considered, the system could be sustainable. Regardless of the existence of IEAs, international environmental conventions shall not neglect the fundamental goal to pursue sustainable development.

• Asian-Australasian Journal of Animal Sciences
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• 제7권2호
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• pp.179-182
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• 1994

A study was conducted using four dairy heifers to determine the effect of 10, 20 and $30^{\circ}C$ environmental temperatures on the physiological responses and heat production, at a fixed level of TDN intake ($60.5\;g/kg^{0.75}\;d$). The analysis showed significant affects of environmental temperature on respiration rate (RR), mean body temperature (Tb), changes in body heat storage (S) and heat production (HP). The HP at $20^{\circ}C$ was almost the same as at $10^{\circ}C$, but the HP at $30^{\circ}C$ was 11% higher than at $10^{\circ}C$. A tendency for an elongation of standing time (ST) with the increase in environmental temperature was also observed. These results suggest that the increase in energy cost of elongation of ST ($9.2\;kJ/kg^{0.75}\;d$) and $1.3^{\circ}C$ increase in Tb ($17.3\;kJ/kg^{0.75}\;d$).

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.933-937
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• 2006

Energy is motive power that makes convenient society. But, our country's energy is depending on most import. Also, energy and environmental issue are important problem in community of nations. The purpose of this study is to analysis the energy consumption and environmental load of EHP and GHP in Medium and small-scaled office building. The annual energy consumption used to cooling and heating by EHP was 10 percent more than GHP. And annual energy cost of EHP was 33 percent more expensive than GHP. But, Compared to the annual $CO_2$ emission, EHP was 6 percent less than GHP. Therefore, equipment selection should be consider environmental load as well as energy consumption and cost.

• 공업화학
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• 제32권6호
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• pp.706-710
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• 2021

In the current research, thermal and catalytic thermogravimetric (TG) analysis of polyethylene terephthalate (PET) over natural zeolite (NZ), olivine, bentonite, HZSM-5, and HAl-MCM-41 were investigated using a TG analyzer and model-free kinetic analysis. Catalytic TG analysis of PET was carried out at multi-heating rates, 10, 20, 30, and 40 ℃/min, under nitrogen atmosphere. Apparent activation energy (Ea) values for the thermal and catalytic pyrolysis of PET were calculated using Flynn-Wall-Ozawa method. Although natural catalysts, NZ, olivine, and bentonite, could not lead the higher PET decomposition efficiency than synthetic zeolites, HZSM-5 and HAl-MCM-41, maximum decomposition temperatures on the differential TG (DTG) curves for the catalytic pyrolysis of PET, 436 ℃ over olivine, 435 ℃ over bentonite, and 434 ℃ over NZ, at 10 ℃/min, were definitely lower than non-catalytic pyrolysis. Calculated Ea values for the catalytic pyrolysis of PET over natural catalysts, 177 kJ/mol over olivine, 168 kJ/mol over bentonite, and 171 kJ/mol over NZ, were also not lower than those over synthetic zeolites, however, those were also much lower than the thermal decomposition, suggesting their feasibility as the proper and cost-effective catalysts on the pyrolysis of PET.

• 아태비즈니스연구
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• 제13권2호
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• pp.139-154
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• 2022

Purpose - This study aims to analyzing of solar power generation cost-benefit. Design/methodology/approach - We analyzed whether there is economic feasibility by selecting parking lots and idle sites located in four areas of Seoul, Gyeonggi, Chungcheong, Jeolla, and Gyeongsang areas nationwide, and analyzing site conditions and installation capacity. Findings - According to the results of the analysis, it was found that there is low profitability in Seoul, Gyeonggi and Chungcheong regions, where the solar radiation was not excellent even if REC is selected through the contract market. However, it is necessary to analyzed the economical validity the profitable validity including environmental benefits (greenhouse gas reduction, NOx, SOx reduction effect) and social benefits (renewable power supply) that is analyzed by income and operating costs which is occurred from electricity sales and REC sales when installing solar power generation facilities. Research implications or Originality - In this study, economic feasibility was evaluated additionally in consideration of environmental and social benefits. In conclusion, it was shown that businesses are not economical when considering only simple financial aspects are also sufficiently economical when it is considering environmental and social benefits.

• 산업공학
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• 제17권spc호
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• pp.122-130
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• 2004

Since the cost of software maintenance occupies about 50~75% in a general successful organization, the software maintenance plays an important role in software life cycle. In particular, if the managed system needs to be operated in a long term or the system is very large and complex, then the maintenance is especially more important. Software maintenance is defined as software modification activities after customer delivery, such as improvement of performance or functionality, error correction, adaptation to environmental changes, etc. In this paper, software cost estimation models are proposed, that is based on productivity of manpower in maintenance projects. In order to do this, the activities of maintenance are classified into function change, non-function change, user support and application operation. The proposed models are constructed and verified based on the real size and cost information of projects in the real world. The approach in this paper is to discriminate the heterogeneous activities in maintenance projects, and then to calculate the respective cost of each discriminated activity. By using the proposed models, the total cost of maintenance project is summed from the costs of four activities. In addition the number of conflicts between owner and order receiver about the amount of cost will be reduced and the reasonable cost estimation system will be established.

• 한국건축시공학회지
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• 제9권1호
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• pp.65-73
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• 2009

Looking at current construction costs estimations of publicly declared public works, there are many instances where estimation criteria are ambiguous and doesn't imply the reality. Up to date, estimation criteria for calculating construction cost estimations are simply by unit area multiplication and stochastic construction cost estimation. However, possibility of making errors are high due to using uniform data that excludes each public work's specifications and environmental conditions. Further, on the aspect of cost management, there is certain limitation in the efficiency of cost management in order-placing stage and commencing-work stage; while efficient cost management and reduction of expenses are highly possible during initial stages of the project. In this respect, the paper adopts positive approach with regards to construction cost estimations of public works and draws common elements from calculation tables of the construction cost estimations from 3 completed domestic construction works; after which, the paper analyzes whether business exposition, construction guide and publicly-declared estimated construction costs that the orderer issued are calculated economically and properly; deducing problems in the process, the paper seeks to recommend rational calculation method on this.

• 대한토목학회논문집
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• 제28권3D호
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• pp.371-381
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• 2008

국내 하천시설물 건설공사는 도로 등의 다른 토목시설공사에 비해서 사업의 금액규모가 상대적으로 작다는 등의 특성으로 인해 사업의 기획 및 계획단계에서의 개략적인 공사비용을 예측하는 기준 단가가 정립되어 있지 않으며, 시설물의 특성을 고려한 합리적이고 체계적인 견적 방법론 또한 존재하지 않는다는 문제점을 가지고 있다. 본 연구는 하천시설물 건설공사의 실적자료를 수집하고 분석하여, 4단계로 이루어진 하천 제방공사 실적정보 구성 체계를 제시하고, 공사비에 영향을 끼치는 인자들을 주요 공종별로 도출하여, 하천시설물 공사의 기획단계에서 적정한 개략공사비를 산정하는 체계적인 방법론을 제시한다.

• 한국해양공학회지
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• 제20권6호
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• pp.108-113
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• 2006

For the past scores of years, our country has driven its land development toward economic growth as its top priority. ut, as a result that almost all developments been promoted excepting environmental values, in fact, they've incurred some bad environmental effects desirable. Especially, as representative examples, we can raise some issues such as damages of the foreshore or coast wet lands by seas reclamation, and coast corrosion by building up of rivers or coast constructions. Recently, many people started to have great interests in businesses of environment preservation or recycling to minimize effects of these environmental matters. However, before beginning public businesses of non-commercial goods relevant to the seas environments, there seemed to be some limitations that can not accomplish under consideration of environmental sides at the same time while performing economic validities and efficiencies with environmental economic analysis, which is already effective in countries advanced in environment, it's a very meaningful course in that citizens' opinions are being influenced in seas environmental policies for their efficient execution. In this research, after modeling coast corrosion preventives with Jeong-am coast of Gangwon Province, and using Contingent Valuation Method being widely used of value measuring methods on Non-commercial goods, we've appreciated environmental economy's validity of construction works and the scale of environmental economic value of beach restoration work.

• 한국습지학회지
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• 제25권4호
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• pp.230-236
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• 2023

하수도 시스템은 공공서비스의 개념 및 습지 등 수환경 보호를 위해 지속적으로 보급이 이루어졌으며, 그 결과 하수도 운영기관의 경영 악화를 초래하였다. 이에 중앙정부 주도하에 하수도 운영기관 경영 효율화를 위해 다양한 하수도 정책을 추진하고 있다. 그 중 중점적인 사항은 비용과 관련된 것이며, 대표적으로 하수도 요금 및 하수도 원인자부담금 등이 있다. 본 연구에서는 국내 기초자치단체 71곳의 하수도 원인자부담금 현황 및 특성을 분석하였다. 그 결과, 1,000,000원/m³ ~ 2,000,000원/m³ 이하가 41곳(57%)으로 가장 많은 것으로 나타났으며, 평균값 1,990,653원/m³ (중앙값 1,918,000원/m³ )으로 나타났다. 또한, 하수도 원인자부담금이 높아질수록 하수도 원인자부담금의 증가율이 높아지는 것 경향을 보였다. 하수도 원인자부담금과 상대적으로 상관성이 높은 기초자치단체 특성 인자는 하수도 요금현실화율과 재정자립도로 분석되었다. 본 연구의 결과는 하수도 원인자부담금의 기초자료로 활용될 수 있으며, 하수도 원인자부담금 적정 수준 산정 방안에 관한 후 속 연구가 필요하다.