• 정보과학회 논문지
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• 제44권8호
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• pp.854-859
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• 2017

기지국(Base Station)에서 인기있는 콘텐츠(비디오)를 캐싱하는 것은 전송 대기 시간을 줄일 수 있는 효율적인 방법이다. 본 논문에서는 콘텐츠 제공자(CP)가 캐싱 절차에 참여하도록 동기를 부여하기 위해 무선 네트워크에서의 사전 인센티브 캐시 메커니즘을 제안한다. 하나 이상의 Infrastructure Provider(InP)와 많은 CP로 구성되어 있는 시스템에서, InP는 InP의 기지국에서 캐시하는 파일 수를 결정하기 위해 CP가 경쟁하는 동안 수익을 극대화할 수 있도록 CP에 청구되는 가격을 정의하는 것을 목표로 한다. 또한 InP와 CP는 Stackelberg 게임이론 내에서 각각 선도자와 추종자로 정의된다. Backward Induction을 기반으로, 각 CP가 각 기지국에서 임대한 캐시 공간의 양을 정확하게 측정한 후, 최적화 문제를 해결함으로써 InP가 각 CP를 임대하는 가격을 계산한다. 이것은 비 균일 가격 체계를 고려한 점에서 기존 연구와 차이가 있다. 수치 결과는 제안 된 방법을 통해 InP의 이익이 균일 가격 책정보다 높다는 것을 보여준다.

• 대한지리학회지
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• 제48권2호
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• pp.272-287
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• 2013

본 연구는 부동산 가격 추정을 위해 자주 활용되는 헤도닉 가격모형(Hedonic Pricing Model)에서의 설명변수, 즉 지가형성요인의 선별 중요성에 대해 기술하고, 이러한 지가형성요인 및 그 효과가 시간의 경과에 따라 어떻게 변화하는지 실증적으로 검토하였다. 전주시를 사례 지역으로 하여 17년간 반복 측정된 표준지 공시지가를 분석 대상으로 하였으며, 자료가 가지는 포섭구조(nested structure) 및 종단성(longitudinal characteristics)을 고려하여 3개 수준으로 구성된 다수준모형(multi-level model)을 설정하여 적합 정도를 평가하였다. 지가형성요인은 공시지가 산정시 활용되는 헤도닉 가격모형의 일종인 비준표(比準表)에 포함된 항목을 중심으로 살펴보았다. 분석 결과, 17년간의 지가 변동 추세는 전주시 세부지역별로 상승 또는 하락하는 등 지역마다 다른 추이를 보였으며, 따라서 종단효과의 모델 반영이 필요함이 확인되었다. 또한 일반적으로 중요하다고 여겨지는 지가형성요인 중 유의하지 않은 요인이 발견되었으며, 특정 시점에서 영향력이 상당히 큰 것으로 판명된 지가형성요인도 시간의 경과에 따라 그 영향력이 약해지는가 하면, 반대로 지가에 미치는 영향력이 초기에는 미약하였으나 점차 뚜렷해지는 요인이 파악되었다. 향후 헤도닉 모형 적용시 이러한 지가형성요인의 동태성을 모델의 구성요소로 고려할 경우 보다 정확한 가격 추정이 가능해질 것이다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.297-299
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• 2014

Petroleum coke has high heating value and low price. Due to the steadily increasing demand for heavy oil processing, the production volume of petroleum coke tends to be expanded. The high availability and low price of petroleum coke have been strongly considered as candidate fuel for power generation facilities. However the high carbon content, high sulfur content and nitrogen content of petroleum fuel are known to produce relatively large quantity of CO2, high NOx and SO2 emission. In this work, a series of numerical simulations have been carried out in order to investigate the effects of swirl flow intensity on combustion furnace, which is most important operating condition. Results show that the temperature distribution was spatially uniform at about 1600K but high temperature region are located quite differently depending on swirl number. In addition, numerical temperature data was compared with experimental temperature data and its temperature difference shows less than 10%. On the other hand, discrepancy between numerical and experimental emission data were slightly large with necessities of improved emission model.

• 반도체디스플레이기술학회지
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• 제22권1호
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• pp.33-38
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• 2023

As the demand for large flexible displays such as tablet computers continues to rise, there is an increasing need for cost-efficient colorless and optically transparent polyimide film that can meet the desired performance, particularly optical transmittance. In this study, we investigated a detailed procedure for achieving optimal optical transmittance using two different combinations of monomers: 6FDA+BAPB and 6FDA+BPA+TFDB. We employed a design of experiment method to systematically synthesize polymers, allowing for the optimization of optical transmittance. In addition, we were able to achieve uniform thickness in the films by using a doctor blade. By comparing the price and optical transmittance of four different monomer combinations, we obtained fundamental data on the production of polyimide films that can be customized to meet the specific price and performance requirements of manufacturers. This approach enables users to select the most suitable polyimide film based on their desired price and performance parameters while achieving optimal optical transmittance.

• KIEE International Transactions on Power Engineering
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• 제5A권1호
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• pp.85-92
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• 2005

In this paper, Nash equilibriums of generation markets are investigated using a game theory application for simplified competitive electricity markets. We analyze the characteristics of equilibrium states in N-company spot markets modeled by uniform pricing auctions and propose a new method for obtaining Nash equilibriums of the auction. We assume that spot markets are operated as uniform pricing auctions and that each generation company submits its bids into the auction in the form of a seal-bid. Depending on the bids of generation companies, market demands are allocated to each company accordingly. The uniform pricing auction in this analysis can be formulated as a non-cooperative and static game in which generation companies correspond to players of the game. The coefficient of the bidding function of company-n is the strategy of player-n (company-n) and the payoff of player-n is defined as its profit from the uniform price auction. The solution of this game can be obtained using the concept of the non-cooperative equilibrium originating from the Nash idea. Based on the so called residual demand curve, we can derive the best response function of each generation company in the uniform pricing auction with N companies, analytically. Finally, we present an efficient means to obtain all the possible equilibrium set pairs and to examine their feasibilities as Nash equilibriums. A simple numerical example with three generation companies is demonstrated to illustrate the basic idea of the proposed methodology. From this, we can see the applicability of the proposed method to the real-world problem, even though further future analysis is required.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2002년도 추계학술발표대회
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• pp.263-268
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• 2002

This paper aimes to analyse the housing market of Ulsan, that changed for Metroplolitan city in 1997. For the housing policy we need sufficient informations on the housing market appeared during the last five years. As a result, we can describe its housing market in a uniform way: Ulsan, compared with other cities, doesn't show varieties in households, housing type, housing conditions etc.. Concerning the housing preference, the results of our survey also show the uniformity. And the price of apartment in Ulsan moves relatively slowly to other cities.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.84.1-84.1
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• 2010

Currently, new and renewable energy come into the spotlight, such as solar energy, wind power, fuel cell, hybrid car etc., due to the energy resource is being depleted. Especially, in order to solve like this problem, the study of solar cell manufacturing systems are being extensively researched such as vacuum process. But the major fault of the vacuum process are its expensive production price. On the order hand, Roll-to-roll printing system, the new technology of solar cell manufacturing, has low production price compare with the vacuum process. Also roll-to-roll printing system can decrease the 95% of waste water and 99.9% of harmful gasses than the vacuum process. So we addressed the roll to roll printing system for the flexible solar cell by using printing technology. This roll-to-roll printing system is comprised of various modules, such as web handling module, fine pattern printing module, dry/curing module, uniform coating module and laminating module etc.

• 한국가금학회지
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• 제25권2호
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• pp.91-98
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• 1998

In order to compare economics of soybean meals (SBMS) imported from Brazil and the U.S., a feeding trial was conducted with 480 commercial broiler chicks (Abor Acres strain) for 38 days. The Brazilian SBM was brownish in color and the protein solubility in 0.2 % KOH solution was 63. 4 %. The U.S. SBM, on the other hand, was a dehulled SBM, and uniform in color (light yellow) and particle size. The protein solubility value of the latter was 76.6 %. Two dietary protein levels (19 % and 21 %) were used for each source of SBM (2x2 factorial). Chicks fed diets containing the U.S. SBM grew significantly faster (P<0.05) and utilized feed more efficiently than chicks fed diets containing Brazilian SBM. Chicks fed diets containing 21 % CP showed better growth performance and profitability than those fed the 19 % CP diets. The price of the U.S. SBM was higher but the feed cost per unit gain was lower than the Brazilian SBM. Results suggest that there are over-cooked SBMs being traded on the Korean rnarket, and attention should be given to not only the price but also the quality of SBMs.

• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.711-720
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• 2007

Apartment housing in the Korean domestic construction industry has had various and high-quality finishing work since the enforcement of price deregulation in 1998. Before the enforcement of price deregulation, feasibility studies of housing projects have not had particular difficulties as uniform description of finishing work items were reflected and finishing work cost also was equalized. However, the recent distinction of finishing work based on the same floor plan brings about project cost variation, along with many effects on construction management due to project cost increment. Accordingly, this paper suggests the improved plan of cost management to control the feasibility study result consistently during the life cycle of a project through an analysis based on cost management phase due to cost blackout, appearing at the commencement of a project, cost gradation caused by high-quality finishing work item, and cost reduction due to the degradation of finishing work after analysis of current apartment construction process focused on finishing work using the IDEF process analysis technique.

• 무역상무연구
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• 제58권
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• pp.149-177
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• 2013

This article introduces and briefly examines the Uniform Rules for Forfaiting (URF)(ICC Publication No. 800), which were prepared by a joint project of the Banking Commission of the International Chamber of Commerce (ICC) and the International Forfaiting Association (IFA), and became effective on January 1, 2013. Forfaiting is a kind of trade financing technic performed by way of a sale and purchase of payment claim between its seller and its buyer, the forfaiter, on a without recourse basis. URF is designed to facilitate global trade finance and embraces all the international payment instruments which are currently used and will be newly developed in the future. URF is expected to be a set of standardized terms and conditions for both the primary and secondary forfaiting markets. In this context, this article first looks into the concept of the forfaiting and certain features and structure of forfaiting transactions. Then this article moves to discussing URF itself. For this it examines (i) the nature and scope of URF and some important definitions provided in URF, (ii) some provisions of URF that apply to the delivery of documents to the forfaiter, the examination, and the acceptance or refusal, of such documents by the forfaiter, and (iii) the payment of purchase price by the forfaiter to its seller, including the matter of "payment under reserve" and repurchase by the seller from the forfaiter. Finally, this article examines liabilities of the parties concerned, before conclusion.