• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.95-96
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• 2002

The operation of proceeding bearing in the conditions of misaligned axis of proceeding and bush leads to the load concentration on the bearing edges causing further mixed lubrication conditions, unstable operation and intensive wear of mating parts. For the design process of proceeding bearing the knowledge of static characteristics determined from the oil film pressure and temperature distribution is very important. For the 3-lobe proceeding bearing, the pressure, temperature and viscosity fields, load capacity, minimum oil film thickness, power loss, oil flow and maximum oil film temperature have been determined by iterative solution of the Reynolds', energy and viscosity equations. The paper introduces the results of theoretical investigations of static characteristics of 3-lobe proceeding bearing operating at misaligned axis of proceeding and bush. An effect of misalignment ratio, length to diameter ratio of the proceeding bearing, the lobe clearance ratio on the static characteristics was investigated. Laminar, adiabatic model of oil film for the solution of Reynolds, energy and viscosity equations was applied.

• 무역상무연구
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• 제52권
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• pp.47-71
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• 2011

This thesis examines the problems faced in the electronic trade platform for which improvements are necessary, and suggests various ways of overcoming those problems. Practical implications regarding the advancement of Korea's u-TradeHub system are as follows. First, from the technical and legal aspects, to make up for a lack of support systems for spread of users, it is required to promote customized advertising strategies through Ministry of Knowledge Economy and establish a global certification system. Second, document standardization and digitalization should be achieved in advance to make the documents distributed through the e-Trade platform in a seamless manner. Furthermore, an ongoing global network development project should be promoted through the e-Trade platform to achieve standardization. Third, from the operational aspect, it is important to maintain an integrated and systematic relationship with related organizations. Because vertical integration among logistics service providers and GSCM are enabled through the e-Trade platform, it is necessary to standardize global network-based linkage and operating systems.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1589-1592
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• 1997

Among the prerequisite abilities (perception of environment, path planning and position estimation) of an autonomous mobile robot, position estimation has been seldom studied by mobile robot researchers. In most cases, conventional positioin estimation has been performed by placing landmarks or giving the entrire environmental information in advance. Unlikely to the conventional ones, the study addresses a new method that the robot itself can select distinctive features in the environment and save them as landmarks without any a priori knowledge, which can maximize the autonomous behavior of the robot. First, an orjentaion probaility model is applied to construct a lcoal map of robot's surrounding. The feature of the object in the map is then extracted and the map is saved as landmark. Also, presented is the position estimation method that utilizes the correspondence between landmarks and current local map. In dong this, the uncertainty of the robot's current positioin is estimated in order to select the corresponding landmark stored in the previous steps. The usefulness of all these approaches are illustrated with the results porduced by a real robot equipped with ultrasonic sensors.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1727-1731
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• 2003

In this paper we proposed backward fuzzy Petri-net to diagnoses faults in power systems by using the time sequence information of protection system. As the complexity of power systems increases, especially in the case of multiple faults or incorrect operation of protective devices, fault diagnosis requires new and systematic methods to the reasoning process, which improves both its accuracy and its efficiency. The fuzzy Petri-net models of protection system are composed of the operating process of protective devices and the fault diagnosis process. Fault diagnosis model, which makes use of the nature of fuzzy Petri-net, is developed to overcome the drawbacks of methods that depend on operator knowledge. The proposed method can reduce processing time and increase accuracy when compared with the traditional methods. And also this method covers online processing of real-time data from SCADA (Supervisory Control and Data Acquisition)

• 품질경영학회지
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• 제31권1호
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• pp.90-108
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• 2003

This study deals with a case analysis on the implementation of ISO 9000/14000 Integrated Management System. The intention is to provide some general guidelines, in particular, to small-to-medium-sized companies that are planning to introduce the Integrated Management System. First we briefly review each of the ISO 9000 series, ISO 14000 series and Integrated Management System. We then investigate the case of a small-sized company that have built and is successfully operating the Integrated Management System. We start with introducing the company, and then examine the background and the procedure for implementing the Integrated Management System. We investigate effects of the Integrated Management System, which are the main focus of this paper. This study is meaningful in that, to our best knowledge, it is the first field report appearing in the literature in regard to the actual implementation of ISO 9000/14000 Integrated Management System in Korea.

• Journal of Information Technology Applications and Management
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• 제11권4호
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• pp.133-145
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• 2004

The two main purposes of this paper are to 1) investigate critical components of university information systems for information resources management, 2) develop a comprehensive framework model of university information systems for e-Business Era. Through a literature review and by employing group decision making techniques with managers of K University, critical components for developing university information systems were identified. The critical components of university information systems are 1) academic affaires. 2) general administration. (3) research administration. (4) information services. (5) management support, (6) cyber education. (7) knowledge management, (8) e-library. (9) mobile service. and (10) IT infrastructures. In the second stage. by employing IT experts in K University and other institutes. a comprehensive framework of university information systems for e-Business era was developed. The comprehensive framework shows that major components for university information resources management are (1) information infrastructure. (2) common operating environments. (3) applications/information services. The results of this study expect to help managers. who are in charge of university information systems. plan to develop information systems based on the framework proposed in this paper.

• Journal of electromagnetic engineering and science
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• 제9권3호
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• pp.159-163
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• 2009

This paper presents the design and implementation of Q-band MMIC phase shifters using InGaAs PIN diodes. The topology using a thin-film microstrip line(TFMS) has been proposed to achieve the desired phase-shift as well as good loss characteristics. Five single-bit MMIC phase shifters have been implemented by using a developed BCB(benzocyclobutene)-based multi-layer fabrication technology. The developed phase shifters have less than 3.4 dB of insertion loss and better than 11 dB of input and output return loss in the frequency range of 43 to 47 GHz. To the authors' knowledge, this is the first demonstration of high-performance InGaAs PIN diode-based MMIC phase shifters operating at Q-band frequencies.

• Journal of the Korean Data and Information Science Society
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• 제17권4호
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• pp.1161-1167
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• 2006

Since microarray data structures are various and complicative, the data are generally stored in databases for approaching to and controlling the data effectively. But we have some difficulties to analyze and control the data when the data are stored in the several database management systems. The existing analysis tools for DNA microarray data have many difficult problems by complicated instructions, and dependency on data types and operating system, and high cost, etc. In this paper, we design and implement the web-based analysis tool for obtaining to useful information from DNA microarray data. When we use this tool, we can analyze effectively DNA microarray data without special knowledge and education for data types and analytical methods.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.24.3-24.3
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• 2008

The signals transmitted from satellites of Global Navigation Satellite System (GNSS) interact with the plasma of the ionosphere. To study the impact of the ionospheric plasma on GNSS applications a comprehensive knowledge of the ionosphere is required. Especially the correct measurement of the ionosphere such as the peak height of the F2 layer peak electron density (hmF2) is important for the GNSS ionospheric model. Anyang ionosonde station ($37.39^{\circ}N$, $126.95^{\circ}E$) has been operating from October 2000 and the accumulated data for 8 years may allow us to obtain climatological characteristics of middle latitude ionospheric F region for GNSS application. We analyzed the variations of the hmF2 and NmF2 over Anyang station for different conditions of solar activity, geomagnetic activity, season, and local time, and we compared our results with the IRI model.

• 한국압력기기공학회 논문집
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• 제5권2호
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• pp.40-44
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• 2009

In this study, Event Corrective Action Supporting System (ECAS) is developed for the accident evaluation in nuclear power plant. The ECAS system can be used in supporting regulator and/or operator under event situation in nuclear power plants. The ECAS system consists of 5 modules including failure location module, failure analysis module, failure integrity evaluation module, system vulnerability evaluation module, and reporting and operating experience feedback module. The ECAS system will be used as sub module of Knowledge-Based Event Evaluation Network (K-EvENT) which is developing for the against the accident in nuclear power plants.