• 지능정보연구
• /
• 제10권3호
• /
• pp.73-89
• /
• 2004

인터넷의 발전과 더불어 사람들이 더 많은 상품 정보에 접근할 수 있게 됨에 따라, 소비자 간(C2C) 전자시장의 거래 규모도 더욱 빨리 성장하고 있다. 시장 경제의 활성화를 위한 소비자 간 전자상거래의 역할이 더욱 강조됨에 따라 소비자 간 전자상거래를 효율적으로 지원할 수 있는 지능형 에이전트 시스템을 개발하기 위해 많은 연구들이 진행되어 왔다. 그러나 대부분의 이러한 연구들은 단순히 시간 흐름에 따라 동일한 상품의 가격만을 협상하는 것에 초점을 맞추고 있다. 협상의 대상을 서로 다른 유사한 상품으로 확장하기 위하여 고객은 가격 외에도 배송 시간이나 결제 방법 등 거래 행위와 관련된 속성까지 포함한 상품의 다양한 속성들에 대하여 협상할 수 있어야 한다. 이 요건을 만족시키기 위해, 본 연구에서는 고객을 대행하는 에이전트가 판매자 및 구매자 양측의 효용을 높이기 위해 가격 외에도 상품 및 거래의 다양한 속성들에 대해 협상할 수 있는 자동협상 방법론과 이러한 방법론을 적용하는데 기반이 되는 에이전트 마켓플레이스를 제안한다. 제안된 e-마켓플레이스와 에이전트를 지원하기 위한 프로토콜과 관련된 시스템 구조들도 동시에 개발하였다.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• 제11B권4호
• /
• pp.169-174
• /
• 2001

A novel simulation scheme of transient phenomenon for the photovoltaic (PV) generation system under the real weather conditions has been proposed in this paper. A grid connected PV array is simulated using PSCAD/EMTDC. The transient changes of the output current of PV array under the real weather conditions is described and the output current of DC/AC converter flowing through the utility power network is also analyzed with the PWM switching width. Moreover, the MPPT control of PV generation system is combined to the system during the simulation for the comparison purposes of the control schemes. The outcome of the simulation demonstrates the effectiveness of the proposed simulation scheme. The result shows that the cost effective verifying for the efficiency or availability and stability of PV generation systems and the comparison research of various control schemes like MPPT under the same real whether conditions are eventually possible.

• 통상정보연구
• /
• 제5권1호
• /
• pp.63-83
• /
• 2003

This paper's objective is to provide insights about the problems and expansion strategies of electronic trade. Korean small and medium-sized firms have adopted the Internet since the end of 1990s in order to reshape their competitiveness, and it is now being utilized as a major export marketing instrument to develop new customers, save export transaction costs ad facilitate new work processes. However, at present, the use of the internet in the field of trading is limited to the collection of market information, owing to legal, technical and institutional restraints between countries. In addition to that, because firms have the difficulties in making the trade contract through the e-trade system, the negative recognition on its' utility has been spreaded gradually between companies. This is one of the barriers to block the expansion of e-Trade between Korean firms. Therefore, this paper points out the problems of e-trade in the environmental, institutional and strategic view and provides many considerations for establishing the expansion strategy of e-trade by the Korean government and trade supporting institutions.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 A
• /
• pp.698-700
• /
• 2004

Electric power restructuring offers a major change to the vertically integrated utility monopoly. Deregulation has had a great impact on the electric power industry in various countries. Bidding competition is one of the main transaction approaches after deregulation. The energy trading levels between market participants is largely dependent on the short-term price forecasts. This paper presents the short-term System Marginal Price (SMP) forecasting implementation using backpropagation Neural Network in competitive electricity market. Demand and SMP that supplied from Korea Power Exchange (KPX) are used by a input data and then predict SMP. It needs to analysis the input data for accurate prediction.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• 제3B권2호
• /
• pp.103-110
• /
• 2003

With significant development of power electronics technology, the proliferation of nonlinear loads such as static power converters has deteriorated power quality in power transmission and distribution systems. Notably, voltage harmonics resulting from current harmonics produced by the nonlinear loads have become a serious problem in many countries. Many photovoltaic power generation systems installed in building systems have harmonics that are the worst object for distribution systems as a utility interactive system, and it tends to spread out continuously. Proposed and implemented in this paper is a multi-function inverter control strategy that allows a shunt active filter function to the power inverter of the photovoltaic power generation system established on a building system. The effectiveness of the proposed system is demonstrated through the simulation of a hypothetical power system using PSCAD/EMTDC.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• 제5B권4호
• /
• pp.366-373
• /
• 2005

This paper presents two new circuit topologies of the dc busline side active resonant snubber assisted voltage source high frequency link soft switching PWM full-bridge dc-dc power converters acceptable for either utility ac 200V-rms or ac 400V-rms input grid. These high frequency switching dc-dc converters proposed in this paper are composed of a typical voltage source-fed full-bridge PWM inverter, high frequency transformer with center tap, high frequency diode rectifier with inductor input filter and dc busline side series switches with the aid of a dc busline parallel capacitive lossless snubber. All the active switches in the full-bridge arms as well as dc busline snubber can achieve ZCS turn-on and ZVS turn-off transition commutation with the aid of a transformer leakage inductive component and consequently the total switching power losses can be effectively reduced. So that, a high switching frequency operation of IGBTs in the voltage source full bridge inverter can be actually designed more than about 20 kHz. It is confirmed that the more the switching frequency of full-bridge soft switching inverter increases, the more soft switching PWM dc-dc converter with a high frequency transformer link has remarkable advantages for its power conversion efficiency and power density implementations as compared with the conventional hard switching PWM inverter type dc-dc power converter. The effectiveness of these new dc-dc power converter topologies can be proved to be more suitable for low voltage and large current dc-dc power supply as arc welding equipment from a practical point of view.

• 무역상무연구
• /
• 제25권
• /
• pp.75-98
• /
• 2005

With the advent of new customs and practice of electronic records, the eUCP provides some useful guidance to accommodate the presentation of the paper documents electronically and also provides necessary rules to allow the UCP and eUCP to work together. There is no denying the fact that many of the UCP articles are not impacted by the presentation of electronic equivalent of paper documents, so the integrated application of the UCP and eUCP will be broad enough to allow for developing practice in this area. This study discusses some theoretical implication for efficient utilization of the global usages of letter of credit through the finding of optimal solution in the state of uncertainty caused by the electronic presentation of documents. This study suggest that the decision rules be developed to show how individuals choose optimal portfolio between the eUCP and the UCP that maximize their expected utility in letter of credit transaction, and also suggest that the optimal portfolio be determined at the point of tangency between the efficient trading line and the highest indifference curve in the mean-variance plane. This study finally recommends three rebuttable doctrines with regard to the relationship between the eUCP and UCP such as linkage characteristics, generation lap propensity, and homothetic application rule, which may be the critical standards for understanding of the integrated usages of the eUCP and UCP.

• 무역상무연구
• /
• 제54권
• /
• pp.99-122
• /
• 2012

According to the United Nations Convention on the International Sale of Goods, the Seller must deliver the goods, hand over any documents relating to the them and transfer the property the to the goods as required by the contract, and buyer must pay the price for the goods and take delivery of them as required by the contract. In particular, the seller provides the documents is important. If the documents are discrepancies in credit, the beneficiary may not receive the payment. So It is important to study on conditions of documents in international trade. Documents provided by the seller shall be determined by express terms. If there is no agreement on the express terms, it shall be determined by the implied terms or governing law terms. In practice Seller shall provide the documents are as follows, For example, transport documents, commercial invoice, certificate of origin, insurance policy, packing list, inspection certificate etc. As stated above if it can not be determined by express terms, it is determined by the implied terms. In international trade, leading to the implied terms is incoterms(R) 2010 and UCP 600. Incoterms(R) 2010 define the seller must provide the goods and the commercial in conformity with the sales contract and any other evidence of conformity that may be required by the contract and UCP 600 are rules that apply to documentary credit. This paper, the practical utility between Incoterms(R) 2010 and UCP 600 is studied.

• International Journal of Advanced Culture Technology
• /
• 제8권3호
• /
• pp.300-306
• /
• 2020

This study analyzes the distributor's inventory model in a two-stage supply chain consisting of the supplier, the distributor and the end customer. The supplier will allow a credit period before the distributor settles the account with him in order to stimulate the demand for the product he produces. It is also assumed that the distributor pays the shipping cost for the order and hence, the distributor's ordering cost consists of a fixed ordering cost and the shipping cost that depend on the order quantity. The availability of the delay in payments from the supplier enables discount of the distributor's selling price from a wider range of the price option in anticipation of increased customer's demand. As a result, the availability of a credit transaction leads to an increase in inventory levels. On the other hand, in the case of deteriorating products in which the utility of the product perish over time, the deterioration rate with time plays a role in reducing inventory levels. In this regard, we analyze the effect of the length of the credit period and the degree of product deterioration on the distributor's inventory level. For the analysis, we formulate the distributor's annual net profit and analyze the effect of the length of credit period and deterioration rate of the product on inventory policy numerically.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권1호
• /
• pp.34-49
• /
• 2015

Market means of spectrum trading have been utilized as a vital method of spectrum sharing and access in future cognitive radio system. In this paper, we consider the spectrum trading with multiple primary carrier providers (PCP) leasing the spectrum to multiple secondary carrier providers (SCP) for a short period of time. Several factors including the price of the resource, duration of leasing, and the spectrum quality guides the proposed model. We formulate three trading policies based on the game theory for dynamic spectrum access in a LTE based cognitive radio system (CRS). In the first, we consider utility function based resource sharing (UFRS) without any knowledge of past transaction. In the second policy, each SCP deals with PCP using a non-cooperative resource sharing (NCRS) method which employs optimal strategy based on reinforcement learning. In variation of second policy, third policy adopts a Nash bargaining while incorporating a recommendation entity in resource sharing (RERS). The simulation results suggest overall increase in throughput while maintaining higher spectrum efficiency and fairness.