• New & Renewable Energy
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• v.3 no.2 s.10
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• pp.31-39
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• 2007

화석연료의 사용으로 인한 자원고갈과 지구온난화 영향 그리고 에너지 안보문제의 해결을 위해 세계 각국들은 대체에너지 개발에 많은 노력을 기울이고 있다. 그 중 수소는 다양한 경로를 통해 생산 가능하고, 수송연료로 사용 시, 유해 물질이 거의 배출되지 않는다는 장점 때문에 가장 주목받는 대체 에너지원이다. 현재는 수소생산 기술개발을 통해 상업화시기를 앞당기려고 하는 수소에너지 시대의 진입시점이라 할 수 있다. 그러나 수소는 생산경로에 따라 다양한 환경성 및 경제성 결과를 도출 할 수 있기 때문에 다양한 평가가 요구된다. 본 연구에서는 국내 수소생산 방식으로 개발/상용화되어있는 Natural Gas Steam Reforming (NGSR), Naphtha Steam Reforming (Naphtha SR), Water Electrolysis (WE)에 대하여, Life Cycle Assessment (LCA)와 Life Cycle Costing Analysis (LCCA) 방법을 사용하여, 수소경로 전반에 대한 즉, 원료채취부터 자동차로 주행하였을 때까지의 각 대상 수소경로의 환경성과 경제성을 평가하였다. LCA와 LCCA 결과는 Naphtha SR과 NGSR 수소경로에서 지구온난화와 화석자원 소모 부문 모두 기존연료 (가솔린, 디젤)와 비교해서 개선효과가 뚜렷하게 나타났으나, WE 수소경로는 오히려 환경부하가 증가되는 것으로 나타났다. 또한 경제성 측면에서는, 수소 판매 시 가솔린과 동일한 연료세율을 부과하더라도 수소가 가솔린에 비해 가격경쟁력을 확보하게 되는데, 이는 주행 시 수소자동차의 연비가 기존 차량에 비해 월등히 좋기 때문에 연료비용의 이점 때문이다. 만약, 수소에 연료세를 부과하지 않는 다면, Naphtha SR로 생산하여 유통한 수소가 수송연료로서 가장 뛰어난 비용효율성을 갖는 것으로 나타났다.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.6
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• pp.636-642
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• 2022

The "Hydrogen Economic Activation Road map" was announced in 2019, and hydrogen demand is expected to exceed 470,000 tons per year in 2022 and keep increasing. Under this circumstance, it has become important to understand the greenhouse gas (GHG) emissions associated with various hydrogen production pathways. In this study, the evaluation of life cycle GHG emissions regarding the hydrogen produced as by-product from coke oven gas (COG) in steel mill is conducted. To cover the possible range of operations, three literatures were reviewed and their data of inputs and outputs for the process were adopted for calculation. Life cycle inventories and emission factors were mostly referred to GaBi and Intergovernmental Panel on Climate Change (IPCC) guidelines, respectively. When there are multiple products from a single process, the energy allocation method was applied. Based on these sources and the assumptions, the life cycle emission values of COG-based hydrogen were found to be 3.8 to 4.7 kg/CO₂-eq./kg-H₂.

• Nuclear Engineering and Technology
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• v.43 no.2
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• pp.141-148
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• 2011

This paper presents the quantitative analysis results of research on the burnup effect on the nuclear fuel cycle cost of BeO-$UO_2$ fuel. As a result of this analysis, if the burnup is 60 MWD/kg, which is the limit under South Korean regulations, the nuclear fuel cycle cost is 4.47 mills/kWh at 4.8wt% of Be content for the BeO-$UO_2$ fuel. It is, however, reduced to 3.70 mills/kWh at 5.4wt% of Be content if the burnup is 75MWD/kg. Therefore, it seems very advantageous, in terms of the economic aspect, to develop BeO-$UO_2$ fuel, which does not have any technical problem with its safety and is a high burnup & long life cycle nuclear fuel.

• Journal of Families and Better Life
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• v.1 no.2
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• pp.59-73
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• 1983

The purpose of this study is to establish the family economy planning in the side of economic welfare and to discuss its problems. Hypothesis testing and survey analysis whether nuclear family have been formed in the urban communities or not are investigated. Also, survey of family economic period are classified in the following manner. First, as the beginning of family, they are interested in savings, children's education and investment of an estate. Third, as the contracting period of family, they rely upon other's financial supports. Therefore, it is desirable for each family to establish family life cycle planning. As the results of hypothesis testing, 1) Nuclear family have been formed in urban communities. 2) The age of housewives is not concerned with whether their husband's parents live in the same house or not. 3)The age of housewives is not concerned with whether their parents lived with them or not. 4) The relationship between the age of housewives and monthly income is not significant. 5) The relationship between the age of housewives and monthly expenditure is significant. 6)The relationship between the age of housewives and monthly savings is not significant.

• Journal of the military operations research society of Korea
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• v.28 no.1
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• pp.136-149
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• 2002

The UAV(Unmanned Aerial Vehicle) offers numerous benefits to the military. The benefits it can provide are to perform an operation without loss of life and economic life cycle cost. This clearly showed us the benefits of using UAVs in the operation, especially in politically hostile and sensitive areas. While the American military first used UAVs, it is Israel that has used them best in real situations. In this paper, it is summarized the types and the OPCONs (Operational Concept) of UAVs and the values. Looking at the technology trends, and it is showed the benefits of UAV in the economic side feasibility, to emphasis on the future values of the UAVs as a newly emerging weapon systems.

• Informatization Policy
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• v.19 no.2
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• pp.85-105
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• 2012

So far, the importance of informatization, as well as investment into it, has been growing steadily. Due to the uncertainties and risks in adopting information technologies, systematic decision-making is definitely needed in investing in a large scale information system. Based on the existing theories about the economic life span of information systems and in consideration of the actual cost involved in the adoption and operation of the systems by the financial institutions in Korea, this study presents the optimal economic life span for all types of information systems in terms of the economic cost and generalizes the optimal life span. The ultimate purpose of this study is to develop a model that could be used in anticipating the timing of economic replacement of the information system of the same type and making decisions on IT investment.

• Korean Journal of Construction Engineering and Management
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• v.2 no.2 s.6
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• pp.59-67
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• 2001

The purpose of this study is to evaluate economics by the Life Cycle cost(LCC) analysis of Steel Box Girder and Prestressed Box Girder bridge types. The study has been performed as a case study. A questionnaire survey for the repair and replacement cycle has been done in order to predict operation and maintenance costs. For LCC analysis and comparison, the present value technique is used. The results of this study are summarized as follows: (1) A LCC analysis model of Steel Box Girder and Prestressed Box Girder bridge types is suggested through a case study. (2) The repair and replacement cycle of elements of them are investigated using a questionnaire survey. (3) As a result of LCC case study, the type of Prestressed Box Girder bridge is analyzed more economic than Steel Box Girder.

• KDI Journal of Economic Policy
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• v.40 no.2
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• pp.53-73
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• 2018

Using an overlapping generations model, this paper examines tax policy effects across generations. The model incorporates housing assets separately from capital assets and includes taxes on labor income, capital income, consumption and housing assets. Tax reforms for each tax rate have different effects on tax burdens across generations and the overall efficiency of the economy, leading to different welfare costs for generations. Specifically, raising housing property taxes results in the smallest welfare loss by future generations, as in the model it does not hurt economic efficiency and the tax burden increases mainly for the elderly, who have accumulated housing assets in preparation for retirement.

• Journal of Families and Better Life
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• v.9 no.1 s.17
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• pp.241-257
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• 1991

The objectives of this study are : to measure the level of rent burden. to examine the independent influences of the variables related to rent burden. to measure the level of family economic problem perception. to examine the differences in the level of family economic problem perception due to rent burden, household characteristics, housing characteristics and rent incresing. For these purpose, a survey is conducted using questionaires. The data used in this study included 369 renters living in Seoul. Statistics uses for data analysis were Frequency Distribution. Percentile, men, Pearson's Correlation, Partial Correlation, One-way ANOVA, Breakdown and Multiple Regression Analysis. Major findings are as follows : The average score of rent burden was 35.87, Therefore rent burden of large cities, rental households is very heavy. Family income, housing facility quality, rent type, and rent incresing have independent influences on rent burden. The average of family economic problem perception is above the mid-point of the scale. The level of family economic problem perception differs due to rent burden, family income, family life cycle, family size, occupation of household head, education leval of household head and homemaker, rent type, housing type, housing size, housing facility quality and rent increases. If the level of rent burden is below 25, family economic problem perception is adequate.

• Journal of Applied Reliability
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• v.8 no.3
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• pp.135-144
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• 2008

The economic life for three types of military wheeled vehicles with load capacities of 1/4, $1{\cdot}1/4$, and $2{\cdot}1/2$ tones has been evaluated on the basis of the equivalent acquisition and operating costs. The economic life of wheeled vehicles were calculated from 12 to 18 years by using the annual equivalent cost method. The equivalent cost was decided at the lowest point of the total amount of equivalent acquisition cost and operating cost. The operating cost were collected from the field data. The evaluated economic life can be very useful for deciding the total life cycle of these three types of military vehicles. The annual equivalent cost method may be also applied to other military equipments such as communication electronics, weapon systems, and other type of vehicles.