• International Journal of Control, Automation, and Systems
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• 제3권spc2호
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• pp.355-362
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• 2005

Deregulations and market practices in power industry have brought great challenges to the system planning area. In particular, they introduce a variety of uncertainties to system planning. New techniques are required to cope with such uncertainties. As a promising approach, probabilistic methods are attracting more and more attentions by system planners. In small signal stability analysis, generation control parameters play an important role in determining the stability margin. The objective of this paper is to investigate power system state matrix sensitivity characteristics with respect to system parameter uncertainties with analytical and numerical approaches and to identify those parameters have great impact on system eigenvalues, therefore, the system stability properties. Those identified parameter variations need to be investigated with priority. The results can be used to help Regional Transmission Organizations (RTOs) and Independent System Operators (ISOs) perform planning studies under the open access environment.

• 한국IT서비스학회지
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• 제23권2호
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• pp.83-97
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• 2024

This study was conducted to examine the effect of institutional mechanisms on customers' trust and continuous purchase intention in open market platforms, The research frame was expanded by setting institutional situations into positive and negative areas in order to examine the relationship between institutional mechanisms and trust in multiple dimensions. The results of this study confirmed that the feedback system, dispute resolution, and intermediary trust factors affect trust in positive areas, and dispute resolution, information security, and intermediary trust affect buyer trust in negative areas. For the relationship between trust and repurchase intention, it was confirmed that if the institutional situation is positive, trust leads to repurchase intention, and in negative areas, trust does not lead to repurchase intention. The results of this study show that institutional mechanisms are a key factor in building trust in online platforms according to institutional circumstances and play a role in offsetting trust in platforms in negative areas.

• 한국전자통신학회논문지
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• 제12권1호
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• pp.1-8
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• 2017

주요 선진국의 전파이용 관리 패러다임이 Command & Control ${\Rightarrow}$ Market Based ${\Rightarrow}$ Open Access ${\Rightarrow}$ Manage By Technology & Technical Analysis로 변화되고 있는데, 이는 다양한 신규 기술 서비스의 출현, 전파이용자의 급증 등 환경변화에 대한 정책대응과 시장활성화를 위함이다. 그러나 이러한 패러다임의 변화에도 혼간섭 등의 영향을 주지 않는 범위에서 전파를 이용해야 한다는 전파관리의 기본원칙은 준수되어야 한다. 전파유효 이용 및 혼간섭을 방지하기 위해 세계 각국은 자국에 적합한전파관리 규제를 법제화하고, 규율하고 있다.

• 통상정보연구
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• 제10권2호
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• pp.283-304
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• 2008

According to globalization and localization of world economics international trade payment method was also changed. A traditional payment was Letter of Credit basis, however it is being increased to various methods such as remittance, documentary collection(D/P, D/A) and open account. In order to acquire a secure export payment, exporters prefer to L/C basis which is guaranteed by a reliable bank. However, the L/C should bear a security so that importers would rather documentary collection than L/C. The reasons for the preference of collection payment rather than L/C are a low commission cost, the conversion of buyer's market from seller's market due to severe competition in the world market, transaction increase between main office and branches and a right to control the goods until executing the payment by exporters. Besides of them, collection payment can handle safer and faster than open account basis. However, the collection payment has a risk which it isn't guaranteed by bank for the payment so that I would suggest countermeasures to minimize the payment risk utilizing the collection basis as follows; using export credit insurance system, a large domestic credit report provider such as D&B for absolutely fresh and new information, a collection proxy service for overseas deferred credit and suggestion specifying to order B/L not straight one on consignee in order to transfer the right of ownership with endorsement without problem.

• 한국전자통신학회논문지
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• 제11권6호
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• pp.553-560
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• 2016

주요 선진국의 전파이용 관리 패러다임이 Command & Control $\Rightarrow$ Market Based $\Rightarrow$ Open Access $\Rightarrow$ Manage By Technology & Technical Analysis로 변화되고 있는데, 이는 다양한 신규 기술 서비스의 출현, 전파이용자의 급증 등 환경변화에 대한 정책대응과 시장활성화를 위함이다. 그러나 이러한 패러다임의 변화에도 혼간섭 등의 영향을 주지 않는 범위에서 전파를 이용해야 한다는 전파관리의 기본원칙은 준수되어야 한다. 전파유효 이용 및 혼간섭을 방지하기 위해 세계 각국은 자국에 적합한 전파관리 규제를 법제화하고, 규율하고 있다.

• Industrial Engineering and Management Systems
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• 제10권1호
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• pp.34-42
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• 2011

Many companies open multiple projects simultaneously due to market trends, which results in a crowding out effect because of limited resources. R&D engineers become overloaded and scheduling of product development is delayed resulting in timing misses and lost sales leads. The company in this case study (Company A), often opens up many projects simultaneously in order to respond to market needs quickly. The engineers are overloaded and, of course, the schedule is delayed. In order to identify problems, Company A began using Dr. Goldratt's Thinking Processes (TP) during new product development (NPD). When the analysis phase of TP was completed, Company A's core problem was identified as "the quantity of kick-off projects." Consequently, new rules and conditions and procedures were proposed for the opening, suspending, stopping, and closing of projects. Finally, the "Future Reality Tree" ensured that the proposed rules, conditions and procedures were set up as an available solution approved for practical application by executives. After a one-year trial run, the results showed that the Project Duration Rate was reduced by 53%, the Project Closed Rate was increased by 140% and the Project on Time Rate was increased from 10% to 68%. The above results give significant evidence of the benefits of the proposed methodology.

• Communications for Statistical Applications and Methods
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• 제21권6호
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• pp.471-486
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• 2014

This study introduces a new type of symbolic data, a candle chart-valued time series. We aggregate four stock indices (i.e., open, close, highest and lowest) as a one data point to summarize a huge amount of data. In other words, we consider a candle chart, which is constructed by open, close, highest and lowest stock indices, as a type of symbolic data for a long period. The proposed candle chart-valued time series effectively summarize and visualize a huge data set of stock indices to easily understand a change in stock indices. We also propose novel approaches for the candle chart-valued time series modeling based on a combination of two midpoints and two half ranges between the highest and the lowest indices, and between the open and the close indices. Furthermore, we propose three types of sum of square for estimation of the candle chart valued-time series model. The proposed methods take into account of information from not only ordinary data, but also from interval of object, and thus can effectively perform for time series modeling (e.g., forecasting future stock index). To evaluate the proposed methods, we describe real data analysis consisting of the stock market indices of five major Asian countries'. We can see thorough the results that the proposed approaches outperform for forecasting future stock indices compared with classical data analysis.

• The Journal of Asian Finance, Economics and Business
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• 제7권10호
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• pp.761-768
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• 2020

This paper explores the barriers to derivative accounting disclosures in Vietnamese companies and ranks their relative importance for effective and efficient remedies. The Delphi technique was applied to get agreement of panel of experts on the measurement of factors hindering disclosure. Unstructured questionnaires were first sent to twelve experts who had both practical experience and academic knowledge in the field to get ideas on the obstructions to derivatives disclosure. The structured questionnaire was designed to get their agreement on barriers to derivative accounting disclosures. The data analysis with mean, median, mode, standard deviation, and quartile has been implemented to ensure the unanimity. Market-related factors, legislation, accountants' attributes, managers' attributes, information technology and communication, and on-site training were the six major obstacles agreed upon by the experts during their in-depth interviews. Then, these factors were ranked by applying the analytical hierarchy process (AHP). The findings confirmed the priority of information technology and communication, which held the greatest weight. Legislation ranked second, followed by market-related factors and on-site training, which explained the impediments to derivatives disclosure. Managers' and accountants' attributes had the least contribution to the barriers to derivative disclosures. The results have important implications for actions to enhance corporate derivative disclosures in Vietnam.

• 유통과학연구
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• 제16권10호
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• pp.31-38
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• 2018

Purpose - The purpose of this paper is to seek some alternative to overcome difficult shipping situations for overcapacity pursuing economy of scale, which is widely spread in world shipping. Research design, data, and methodology - The research method to be adopted is first to review evolution of larger ships in terms of theoretical overview, and shipping market is examined, and it is studied some problems and solutions in relation to larger ship as field research aspects. Results - Supply and demand of shipping market is flexible and unpredictable nature of market. Sometime fierce competition has spread out the market, and shipowner may deploy mega ship in terms of economy of scale, etc., to overcome the difficult market situations. Both carrier and shipper have their own positions in this matter concerned. However, it causes some problems in the market including port matters, etc. Therefore, it is asked to solve this problems of larger ship employed in the markets, throughout shipping alliances, etc. Conclusions - Over tonnage done by larger ship has caused some problems in the shipping markets, forming monopolistic market by small number of larger shipping companies, destroying oligopolistic nature of shipping business, therefore, the answer is strategic alliance to collaborate each other.

• 한국멀티미디어학회논문지
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• 제14권3호
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• pp.440-448
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• 2011

스마트 폰, 개인용 기기 등을 비롯한 다양한 시스템들에서 그래픽 기반의 사용자 인터페이스를 개발하기 위한 OpenGL 계열 렌더링 표준에 대한 수요가 증가하고 있다. 또한, 항공용, 군사용, 의료용, 차량용 분야의 수요를 중심으로 형성된 세이프티-크리티컬(safety-critical) 시장에서는 OpenGL의 세이프티 크리티컬 프로파일로 개발된 OpenGL SC 표준이 중요한 역할을 담당한다. 본 논문에서는 OpenGL SC 표준을 비용 대비 효과적으로 제공하기 위해서, 기존의 임베디드 시스템들에서 비교적 널리 사용되고 있는 OpenGL 1.x 파이프라인 상에서 OpenGL SC 에뮬레이션을 제공하는 방법을 제안한다. 우리가 제안하는 방법은 임베디드 시스템에서 낮은 개발비로 OpenGL SC 표준을 제공할 수 있으며, 임베디드 시스템용 PC 개발 환경에서의 에뮬레이션용을 위한 필수 요소이기도 하다. 최종 결과는 리눅스기반 시스템과 VxWORKS 기반 시스템에서 표준에 맞게 작동하고, 적합한 실행 속도를 보였다.