• Journal of Electrical Engineering and Technology
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• 제6권3호
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• pp.302-310
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• 2011

Congestion management is one of the most challenging tasks of a system operator to ensure the operation of transmission system within operating limits. In this paper, cluster/zone method and relative electrical distance (RED) method for congestion management are compared based on the considered parameters. In the cluster/zone method, rescheduling of generation is based on user impact on congestion through the use of transmission congestion distribution factors. In the RED method, the desired proportions of generations for the desired overload relieving are obtained. Even after generation rescheduling, if congestion exists, load curtailment option is also introduced. Rescheduling cost, system cost, losses, and voltage stability parameter are also calculated and compared for the above two methods of congestion management. The results are illustrated on sample 6-bus, IEEE 30-bus, and Indian utility 69-bus systems.

• Journal of Communications and Networks
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• 제4권2호
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• pp.136-147
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• 2002

In this paper, the maximal capacity of the data network link has attempted to be exploited by using the dynamic allocation strategy. We propose a new methodology based on the economic models for competing traffic classes (classes of sessions) in packet networks. As the demand for network services accelerates, users' satisfaction to the service level might decrease due to the congestion at the network nodes. To prevent this, efficient allocation of a networks resources, such as available bandwidth and switch capacity, is needed. By using the so-called user profile as well as the utility (e.g., data rate) functions, it is possible to allocate data rates and other utilities using the arbitrary number of QoS classes, say $0.01,...,$10.

• 산업경영시스템학회지
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• 제18권34호
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• pp.51-60
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• 1995

The key competition factor of manufacturing industries has progressively changed from cost to quality and time. Recently, the manufacturing environments more rapidly change than before. So, many companies want to introduce a advanced manufacturing system like CIMS to meet various user's needs and short delivery. But there is a considerable gap between the decision to invest and the achievement of promised benefits. Managers, generally, cannot afford CIM invesment unless they can determine beforehand that CIM will work in thier company and that will provide a coherent strategy and satisfactory return on investment In many cases, it is impossible to justify CIM investment by only economical analysis. Decision making problems like CIM investment are of a multiple objective nature. So, decision making process and multiattribute utility function are very useful methods to evaluate CIM justification In this paper, we described the key functions of CIM justification evaluation using IDEF methodology and developed the applicattion procedure of DMP and MUF method for CIM justification.

• 디지털산업정보학회논문지
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• 제10권1호
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• pp.147-155
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• 2014

The rapid increase in the penetration rate and diverse utility of smart devices opens an opportunity for a development in creating a user-oriented ubiquitous system. And it allows audiences to deploy the exhibition-helping contents regardless of the restriction of place and time with using the smart devices of audience themselves. Also it needs to build a mobile web-based portal system for the related services. To do this, Firstly, it needs the corresponding strategies on a smartphone-based environment such as technical competence, systematic preparation of exhibition with compatible mobile contents, and a compatible channel for interactivity. Secondly, it needs the differentiation of exhibition guide with the existing system: an adoption of augmented reality, panoramic technology and simulation effect aiming for an improvement in a sense of immersion and reality for audience, and building up additional contents with a diversity of formats of image, sound, and video for customer satisfaction.

• 한국군사과학기술학회지
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• 제12권1호
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• pp.60-69
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• 2009

Recently, request far application of advanced commercial technology to the defense acquisition process, to reduce the budget and shorten development time, has been increased. To accomplish these goals, the Advanced Concept Technology Demonstration(ACTD) is used for the defense acquisition process in Korea. And User Utility Assessment is tested to make a decision for transition to acquisition process. But this process does not include measurement of technology maturity and impacts of interface and interaction among the technologies. In this research, we propose the needs of measurement of TRL and IRL and application of SRL to reduce the risk during development phase, to understand the relations of technologies, and to fulfill the requirement far transition of the ACTD project to system development and demonstration process.

• Journal of Communications and Networks
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• 제12권3호
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• pp.253-265
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• 2010

The problem of pricing for a telecommunication network is investigated with respect to the users' sensitivity to the pricing structure. A functional optimization problem is formulated, in order to compute price reallocations as functions of data collected in real time during the network evolution. No a-priori knowledge about the users' utility functions and the traffic demands is required, since adaptive reactions to the network conditions are sought in real time. To this aim, a neural approximation technique is studied to exploit an optimal pricing control law, able to counteract traffic changes with a small on-line computational effort. Owing to the generality of the mathematical framework under investigation, our control methodology can be generalized for other decision variables and cost functionals.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.118-119
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• 2013

Many pictures are taken in construction sites. However, the pictures are not being managed effectively. In this study, the need for vector-photo have been raised which combines pictures and 5W1H information, and the vector-photo format have been suggested. A test module and user-interface have been developed for validating an utility of the format proposed.

• 한국IT서비스학회지
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• 제7권1호
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• pp.45-62
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• 2008

This review examines the rapid growth of qualitative and quantitative of telecommunication industry for past couple of years from customer's viewpoint. Most of the telecommunication products were positioned in the market by the businesses and government's support, but the entity of telecommunication products were never interpreted from the user's viewpoint. Even though, various kinds of telecommunication services have been actively discussed by businesses, government, and IT professionals, it has not been sufficiently discussed by the marketing academia where they need to focus a lot on customer's utility. For the purpose of providing an insight of the telecommunication service marketing strategy, this study looked over old and new directions of growth, failure and evolution of services by focusing on two main pillar of communication business, which is high-speed internet and mobile phone service. Additionally, the research explains and mentions the limit and trend of the telecommunication service marketing, and the future research task that needs to be solved.

• 전기학회논문지
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• 제61권1호
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• pp.41-49
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• 2012

This paper describes the operation mode development for the grid-tied PMSG(permanent magnet synchronous generator) wind power system combined with a battery energy storage. The development of operation modes was carried out through simulations with PSCAD/EMTDC software and experiments with a 10kW hardware prototype. The detailed simulation models for PMSG wind power system and battery energy storage were developed using user-defined models programed with C-code. A 10kW hardware simulator was built and tested in connection with the local load and the utility power. The simulation and experimental results confirm that the grid-tied PMSG wind power system combined with battery energy storage can supply highly reliable power to the local load in various operation modes.

• 대한원격탐사학회지
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• 제5권1호
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• pp.29-39
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• 1989

A study to develop generalized and systematically designed satellite image processing software system on mainframe computer was successfully carried out. Commercially available softwares such as LARSYS were analyzed and modified, and well known satellite data processing algorithms were implemented into comprehensive software. New algorithms were also presented and developed. The contents of developed softwere system may be divided into 8 major sections: menu and user interface, data file management, preprocessing, enhancement in monochrome image, multi-dimension image analysis, scene classification, image display/hardcopy, image handle utility software. Some additional software such as GIS and DBMS will make this software more comprehensive and generalized one for the satellite data processing.