• 전자공학회논문지A
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• 제33A권4호
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• pp.37-46
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• 1996

In this paper, we analyzed the performance improvement of the DS-CDMA/dPSK cellular mobile communication system with CCI canceller and RAKE receiver techniques in mobile radio channel which is characterized by AWGN, Multi-user interference (mUI) and frequency-selective rayleigh fading. System capacity i.e., number of user per cell has been derived and the evaluated results are shown in figuraes as a function of PN code sequence length, number of RAKE receiver tap, BER and E$_{b}$/N$_{o}$. The voice activity factor is assumed to be 3/8 the number of sectors in a cell 3 and MUI is modeled as gaussian process. From the results, the capacity of the DS-CDMA/DPSK cellular mobile communication system is improved by adopting CCI canceller. When we adopt the RAKE receiver to mitigate the multipath fading, the error performance is improved and the amount of improvement is proportional ot the number of taps L in the case that each tap contains a signal component and the better of improvement can be obtained, the smaller of the SNR difference in each tap. The system capacity is more increased when the CCI canceller and the RAKE receiver is used in cascade.

• 한국IT서비스학회지
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• 제7권2호
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• pp.223-242
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• 2008

We assess service delivery system for outpatients of general hospital(A) using service blueprint. Service blueprint for outpatients' service process currently being implemented in general hospital(A) is analysed to improve hospital services and define hospital service delivery system more accurately. In addition, comparative analysis of service blueprint between before and after improvement is conducted to find that health care services Is now more customer-oriented and hospital employees can link their duties to service delivery system. Dealing with the efficiency of health care service delivery system based on service blueprint analysis is expected to pave the way for continual service quality improvement of general hospitals in the future. The analysis of service blueprint of outpatients' service process suggested in this study is useful for setting strategies for health care service. It also helps service process design and service digitalization of other general hospitals in the future.

• 정보관리학회지
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• 제21권4호
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• pp.133-152
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• 2004

정보시대의 도래로 정보량은 기하급수적으로 증가하게 되었고, 이러한 대량의 정보로부터 이용자 개개인에게 적합한 정보를 적시에 제공할 수 있는 방법으로 SDI 서비스가 연구${\cdot}$개발되어 왔지만, 현실적으로 그 활용도는 매우 낮은 것으로 조사되었다. 이에 본 논문에서는 그 원인을 분석하고 SDI 시스템의 성능을 개선시킬 수 있는 적합성 피드백 기반 SDI 시스템을 개발하고자 하였다. 본 연구의 실험을 위해 개발된 실험시스템은 이용자 최소개입 피드백기반 SDI 시스템, 완전자동 피드백기반 SDI 시스템, 그리고 이용자 최대개입 피드백 기반 SDI 시스템이며, 새로 개발된 3개 시스템의 성능 개선정도를 평가하기 위해 네 번째 시스템으로서 전통적인 SDI 서비스에서 사용하고 있는 방법으로 시스템을 개발하였다. 실험결과 이용자 최대개입 피드백 기반 SDI 시스템이 가장 높은 성능을 보여 주었고, 완전자동 피드백 기반, 이용자 최소개입 피드백기반, 전통적 SDI 시스템 순으로 나타났으며, 피드백기반 시스템들은 피드백이 진행될수록 그 성능이 향상되는 것으로 나타났다.

• 의학교육논단
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• 제22권2호
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• pp.131-142
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• 2020

A systematic educational program evaluation system for continuous quality improvement in undergraduate medical education is essential. Monitoring and evaluation (M&E) are two distinct but complementary processes referred to in an evaluation system that emphasizes formative purpose. Monitoring involves regular data collection for tracking process and results, while evaluation requires periodic judgment for improvement. We have recently completed implementing an educational evaluation using the M&E concept in a medical school. The evaluation system consists of two loops, one at the lesson/course level and the other at the phase/graduation level. We conducted evaluation activities in four stages: planning, monitoring, evaluation, and improvement. In the planning phase, we clarified the purpose of evaluation, formulated a plan to engage stakeholders, determined evaluation criteria and indicators, and developed an evaluation plan. Next, during the monitoring phase, we developed evaluation instruments and methods and then collected data. In the evaluation phase, we analyzed results and evaluated the criteria of the two loops. Finally, we reviewed the evaluation results with stakeholders to make improvements. We have recognized several problems including excessive burden, lack of expertise, insufficient consideration of stakeholders' evaluation questions, and inefficient data collection. We need to share the value of evaluation and build a system gradually.

• 조명전기설비학회논문지
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• 제22권1호
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• pp.79-86
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• 2008

국내 및 국외에서도 마찬가지로 전기설비 안전점검에 대한 부분이 발전된 정보통신 기술(IT: Information Technology)에 접목 시켜 실시간으로 서비스를 제공하는 추세에 있다. 전기설비와 관련된 전기안전 부가서비스의 활성화를 위한 방향과 새로운 고부가 비즈니스 사업 창출을 위해서 어떤 부분에서 개선 및 추가되어야 할 부분인지에 대하여 본 논문에서 조사하였다. 따라서 전력 부가 서비스의 활성화 방향에 대하여 실시간 원격 감시 시스템의 활성화 부분과 아크 차단기 도입의 필요성 및 관련 법 부분에 대해 조사 분석하였다.

• Tribology and Lubricants
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• 제11권2호
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• pp.56-62
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• 1995

The anisotropic pressure distribution of the hydrodynamic bearing may generate the unstable vibration phenomenon over a certain speed. These vibrations, known as whirl, whip or rotor instability, cannot be sustained over a wide range of rotational spees. Besides these vibrations not only perturb the normal operation of a rotating machine, but may also cause serious damage to the machinery system. And, it is really impossible to change one parameter without changing others, or difficult to fabricate the modified non-circular type bearing, with all the other cures used just now, In this study, hybrid bearing with magnetic exciter is designed for stability improvement of hydrodynamic bearing rotor system without changing mechanical parameters. For stability study, eigenvalue study of the bearing-rotor system is executed by finite element method and results of analyses and experiments show the possibilities of the stability improvement of the hydrodynamic bearing system by using the electricmagnetic force.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.145-150
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• 2003

The national subway went under construction in 1971, and after three years of endeavor, Seoul subway line number one opened for traffic in 1974. Line number two went under construction in 1978 and it opened for traffic in 1984. With the use of safety operation for more than 20 years, the life cycle nearly came to an end. Therefore the improvements for the safety operation are unavoidable. The total system should not be affected when the new and conventional systems are overlapped, the system operation is in the initial stage, and it confronts the situation of abnormal operation. However, there is a total lack of experience in construction and improvement for the trains that are in the use of large transport and density headway. In this paper, we propose an improvement method of the subway signalling system using ATO (Automatic Train Operation control scheme) to which the latest Digital ATC is applied, and examine the first application model of ATO system.

• 한국주거학회논문집
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• 제22권4호
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• pp.51-61
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• 2011

This study aimed to grasp trends of the discourse for improving living conditions carried out since 1920's, when the sense for mending the irrationality of conventional living emerged in various magazines. Among the movement, women intellectuals played an important roles to discuss reforming daily life and unhealthy, inconvenient houseworks. This study found the ideological background and direction of this discourse, and estimated its important role for housing improvement, analyzing the contents of articles published in representative womens' magazines of the modern times. In the discourse, they thought that it was most important to make houseworks brief and efficient, and concentrated on building rational environment for houseworks. As reforming kitchen system, heating system (Ondol) should be separated from cooking system to improve hygienic and economical condition of houseworks. Reformed kitchen would be equipped with new installations for effectiveness, lightened by sunlight through windows, and finished floor with cement and drainage for sanitation. Also, they suggested new ways of living, planning modern houses with reformed kitchen system, thinking about moving path and distance of housewives. This discourse would be a foundation to the change of kitchen system up to now.

• 한국항만학회지
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• 제13권1호
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• pp.51-64
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• 1999

This study is on the focus of the cost-effective and time-effective in the BCTOC which commenced the On Dock Termainal System in 1998 for the first time in Korea. On this process of study two categories should be considered : (1) Improvement on Business Process (2) Improvement on Information Technology. With these two accesses a new future-oriented and prospective model could be put on our hand as follows. (1) Improvement on Business Process \circled1Consistency of container In-Out Operation \circled2Simplicity of Rate appraisal \circled3Unified operation on Billing and Request (2) Improvement on Information Technology \circled1Scale up the Information Application \circled2Constructing an one-spot simultaneous Information Holding System \circled3Combination of Internet and Integrated Database System.

• 대한전기학회논문지:전력기술부문A
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• 제52권11호
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• pp.625-631
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• 2003

The purpose of this paper is to assess experimentally system stability of the 154 ㎸ transmission system due to the current of the forthcoming AC High-Speed Railway (HSR) era. It introduces a simple method to evaluate the system stability The proposed method also shows the relationship between stability and power losses, and the stability indices made by the numerical process proposed in this paper will be used to assess whether a system can be stabilized or not. This paper also presents the improvement of the stability via loss reduction using STATCOM. Reactive power compensation is often the most effective way to improve both power transfer capability and system stability. The suitable modeling of the electric railway system should be applicable to the PSS/E. In the case study the proposed method is tested on a practical system of the Korea Electric Power Corporation (KEPCO) which will be expected to accommodate the heavy HSR load. Furthermore, it prove that the compensation of voltage drop and its by-product, loss reduction is closely related to improvement of system stability.