• 대한원격탐사학회지
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• 제38권4호
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• pp.421-434
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• 2022

Fine particulate matter (PM2.5) has been the biggest environmental problem in Korea since the 2010s. The present study considers the value of urban forests and green infrastructure as an ecosystem service (ES) concept for PM2.5 reduction based on satellite and spatial data, with a focus on Seoul, Korea A method for the spatial ES assessment that considers social demand variables such as population and land price is suggested. First, an ES assessment based on natural environment information confirms that, while the vitality of vegetation is relatively low, the ES is high in the city center and residential areas, where the concentration of PM2.5 is high. Then, the ES assessment considering social demand (i.e., the ESS) confirms the existence of higher PM2.5 values in residential areas with high population density, and in main downtown areas. This is because the ESS of urban green infrastructure is high in areas with high land prices, high population density, and above-average PM2.5 concentrations. Further, when a future green infrastructure improvement scenario that considers the urban forest management plan is applied, the area of very high ESS is increased by 74% when the vegetation greenness of the green infrastructure in the residential area is increased by only 20%. This result suggests that green infrastructure and urban forests in the residential area should be continuously expanded and managed in order to maximize the PM2.5 reduction ES.

• Current Photovoltaic Research
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• 제8권3호
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• pp.86-93
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• 2020

The investment in solar and wind generation is rapidly increasing with government's renewable expansion policy and Renewable Portfolio Standard (RPS). Since the large penetration of solar and wind generation increases the variability and uncertainty of supply and demand balance in power system, the government is pursuing the policy of supplying energy storage system (ESS) linked to renewable energy. ESS contributes to the ease of transmission and distribution grid by shifting PV generation from daytime to evening hours. Recently, the declining market price of REC as ESS incentive, policies to cut down incentives and limited ESS storage due to fire events lead to the aggravation of long-term profitability, thus working as a barrier of ESS spreading. In this study, the factors affecting the profit of ESS are analyzed and brief indicators are derived. Based on the indicators, the profit changes are analyzed considering the variation of REC market price and REC incentive weights. Based on the profit change with respect to the increase of ESS capacity, economical ESS installation capacity is suggested.

• 전기학회논문지
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• 제60권6호
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• pp.1091-1096
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• 2011

Currently, the concern about the environment is the issue all over the world, and in particular, carbon emissions of the power plants will not be able to disregard from the respect of generation cost. This paper proposes DR (demand response) as a method of reducing carbon emissions and therefore, carbon emissions cost. There are a number of studies considering DR, and in this paper, the effect of DR is focused on the side of carbon emission reduction effect considering Time-Of-Use (TOU) program, which is one of the most important economic methods in DSM. Demand-price elasticity matrix is used in this paper to model and analyze DR effect. Carbon emissions is calculated by using the carbon emission coefficient provided by IPCC (Intergovernmental Panel on Climate Change), and generator's input-output characteristic coefficients are also used to estimate carbon emission cost as well as the amount of carbon emissions. Case study is conducted on the RBTS IEEE with six buses. For the TOU program, it is assumed that parameters of time period partition consist of three time periods (peak, flat, off-peak time period).

• Ocean and Polar Research
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• 제32권1호
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• pp.23-40
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• 2010

This study investigated the effects of imported fisheries products on WTO/DDA tariff negotiations. To calculate the results, the study estimated the demand functions of imported fisheries products by using unit root and cointegration approaches. These approaches allowed us to solve spurious regression problems with macro-economic variables. In addition, this study surmised the effects of change by individually imported fish products from a tariff negotiation model using price elasticities of estimated import demand function. In a process of the analysis for estimating import effects, this study found out that 39 out of 128 imported fish products had positive (+) price elasticities or did not exhibit cointegrations. To cure this problem, this study suggested that the effects of these 39 imported products be estimated with the average variation rate of import volume, rather than by the Ordinary Least Squares approach. In this study, a case-study of tariff formula with coefficient 8 based on a 'Swiss formula' for priority duty rate of 2001 and 2008 was used by to analyze the effect of change in the 128 imported fish products of both years, respectively.

• 무역상무연구
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• 제69권
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• pp.63-84
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• 2016

Article 77 of CISG requires an aggrieved party, the promisee, claiming damages to take reasonable measures to mitigate losses. The reasonable measures required hereunder are limited to those that can be expected under the circumstances having regard to the principle of good faith. When taking such measures, the aggrieved party must do so within a reasonable time under the circumstances. The expenses incurred in taking such measures are recoverable from the promisor. If the aggrieved party fails to do so, the damages recoverable from the promisor are reduced in the amount the loss that should have been mitigated. The aggrieved party's duty to mitigate damages applies to claim for damages only. That is, the violation of this duty should not be invoked against other remedies available under CISG, such as the right to claim specific performance, the right to claim for the price or the right of reduction of price. In practice, under the provision of article 77, the aggrieved party, the seller or the buyer, is often required to enter into a substitute transaction as a measure to mitigate losses and many cases involving a substitute transaction are internationally reported. Therefore this paper intends to provide a certain understanding of the aggrieved party's duty to take measures to mitigate losses based on such cases reported.

• 한국유통학회지:유통연구
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• 제2권1호
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• pp.143-174
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• 1997

The model applied in this paper is based on the theory of economic order quantity (EOQ). EOQ model is introduced to explain the improvement of the transaction efficiency through the cooperative purchase. We examine explicitly how horizontal cooperation affects vertical transactions. A result of the analysis is that a seller can prefer transacting with a cooperative rather than with each buyer separately, even if he reduces the selling price of the product. Without increasing the demand for the product, this result is that dealing with a cooperative, rather than separately with each buyer, decreases the transaction cost for the seller-buyers system, the cost reduction more than off-setting the effect of price decrease on the sellers profit. For a coopative consisting of any number of buyers, Pareto efficient ordering policies that maximize the joint cost saving for the seller-buyers system are identified. We then discuss the conditions under which a cooperative under consideration can be modified to increase efficiency gain. Next, we relax the assumption that all buyers participate in a single cooperative and examine the issue of how many cooperatives, each consisting of a subset of the buyers, should be formed to maximize the total cost saving for the seller-buyers system. Finally, the issue of shapley value to divide the cooperatives gain among its members is discussed.

• 한국수소및신에너지학회논문집
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• 제27권4호
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• pp.447-461
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• 2016

Recently, the Renewable Fuel Standard(RFS) has been commenced from July 31, 2015 in the New and Renewable Energy Act for expanding the supply of renewable energy and reduction of national GHG target in Korea. The biodiesel is only a means of implementation for the RFS, therefore the biodiesel supply expansion is important for fulfilling the RFS obligation policy. The major key points of the biodiesl supply are expanding domestic feedstocks due to the over 60% dependence on foreign feedstock and reducing the price of feedstock because of the over 70% occupation of feed stock price in the biodiesl production cost. Therefore, we estimated actual amount of potential feedstocks which are possible to use for biodiesl production in Korea and investigated technical and political improvements for expanding biodiesl. For estimating a potential feedstocks, first selected the potential biodiesl feedstocks by investigating the status of global biodiesl feedstocks and then analyzed the possible potential amount of each feedstock by surveying the generation situations, the distribution structures and the technical level.

• 한국수소및신에너지학회논문집
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• 제20권1호
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• pp.9-21
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• 2009

As one of the alternative solution for energy and environmental issues such as climate change, energy security, oil price, etc., hydrogen energy has been getting so much attentions these days. This paper analyzed the $CO_2$ emission, costs, and energy consumptions when the hydrogen energy was introduced to transportation, specifically in Sedan sector using the energy system model, MARKAL. As results, 21.5% of $CO_2$ emission in 2040 could be reduced and additional 76 billion dollars will be needed in the high energy price scenario. The amount of energy saving mainly due to the replacement of existing car to hydrogen vehicle was 16% of the final energy consumption in 2040.

• 한국농촌간호학회지
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• 제2권2호
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• pp.111-119
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• 2007

Purpose: In this study consumers' preference for housing for elderly people was analyzed as well as the recognition by elders of silver town facilities, and their preference for service provided by silver town. The study was done to provide basic data for the development of silver town facilities that are low in cost and high in efficiency. Methods: A sample research was used in this study to analyze the understanding of old age, silver town, and service preference. Results: First, interest and intention to live in silver town was very positive, however low cost was also preferred and that is quite different to current silver towns of Korea. Second, women have more understanding of, requests for, and intention to move into silver town facilities than men. Women's demands for silver town facilities must be reflected in the development strategy of silver towns. Third, the most important part of activating silver town facilities is price strategy. Government political support is required in order to keep silver town move-in costs affordable. Fourth, silver towns must function as total service complex towns. Conclusion: This study is meaningful as efficient operation of silver town is suggested rather than facility degradation to achieve price reduction. This result is important to the development of silver towns based on consumer preference, as it suggests a development direction that is focused on securing differentiated services and programs.

• 전기학회논문지
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• 제63권12호
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• pp.1627-1636
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• 2014

In real-time electricity price environment, the energy management system can provide the significant advantage to the residential, commercial and industrial customers since it can reduce the electricity charge by controlling the load operation effectively in response to time-varying price. However, the earlier studies for load management mainly focus on the residential and commercial customers except for the industrial customers because most of load operations in industrial sector are intimately related with production schedule. So, it is possible that the inappropriate control of loads in industrial sector causes huge economic loss. In this paper, therefore, we propose load control algorithm for factory energy management system(F-EMS) to achieve not only minimizing the electricity charges but also maintaining production efficiency by considering characteristics of load operation and production schedule. Considering characteristics of load operation and production schedule, the proposed load control algorithm can reflect the various characteristics of specific industrial customer and control their loads within the range that the production efficiency is maintained. Simulation results show that the proposed load control algorithm for F-EMS leads to significant reduction in the electricity charges and peak power in industrial sector.