• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.5
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• pp.459-467
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• 2002

A compact, lightweight and low-cost Planar Inverted-F Antenna(PIFA) for wireless LAN communication in the 5 GHz band is designed. The antenna is designed using the IE3D, the simulation tool of the Zeland Inc.. The characteristics of the implemented antenna are measured and analyzed. The antenna is resonated at the 5.25 GHz and its bandwidth is about 580 MHz under the condition of VSWR$\leq$1.5.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.9
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• pp.80-85
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• 2011

In this paper, complex discharge type ozonizer with a screw type electrode has been designed and manufactured for environmental improvement using low power and high efficency ozoniazer. The complex discharge type ozonizer is equipped with three electrodes{central electrode(CE), internal electrode(IE) and external electrode(EE)}. Ozone of the complex discharge type ozonizer is generated by superposition of silent discharge and surface discharge in discharge space as a screw type CE and IE are respectively applied to AC high voltage of inverse-polarity has $180[^{\circ}]$ phase difference, EE is common electrode. In this time, when oxygen has been used as supplied gas, the maximum values of ozone concentration, ozone generation and ozone yield were obtained as 8,334[ppm], 3,249[mg/h] and 65.3[g/kwh].

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.10
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• pp.1298-1302
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• 2018

Minimum Efficiency Performance Standard (MEPS) has already been operated in many countries. In particular, the European Union (EU) has entered the IE3 stage since 2017. Korea will also enter the IE3 phase from October 2018. As for Korea, there is still a restriction on induction motors only. But, in the EU and the United States, efficiency regulation of variable speed drives is being deeply examined. Standards related to this are gradually being fixed. In this paper, the current status and the direction of global standards related to the efficiency of motors, inverters and systems are reviewed. And the case of improving the efficiency of the system including the motor will be examined.

• Journal of the Korean Society of Systems Engineering
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• v.7 no.1
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• pp.53-56
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• 2011

Configuration management plays a key role in systems engineering process for any project from earlier stage of development. It consists of five major activities, ie., configuration management planing, configuration identification, configuration control, configuration status accounting and configuration verification and audit, and is essential to control system design, development and operation throughout entire life cycle of the system development. And it is directly associated with other part of systems engineering management process, ie., technical data management which provides traceability of important decisions and changes during development. In this paper, we describe how to apply CASE(Computer-aided Systems Engineering) tool-Cradle for the configuration management to achieve effectiveness of Technical Management process.

• Journal of Korean Library and Information Science Society
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• v.37 no.2
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• pp.127-144
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• 2006

This study intends to analyze the integrated search methods in digital libraries environment. To categorize various integration methods, I investigated the developmental properties and integration types of digital libraries from a users point of view. And then, I reviewed the current best practices of library portal which are JISC Information Environment, NSDL OCKHAM and Korea Knowledge Portal Initiatives. Nextly, I derived the two methods of Integrated search mechanisms such as aggregated search and distributed search that is useful in the digital libraries environment.

• Journal of the Semiconductor & Display Technology
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• v.5 no.2 s.15
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• pp.37-39
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• 2006

We employed in-situ spectroscopic ellipsometry(SE) and imaging ellipsometry(IE) to study the interaction of water and photoresist(PR) in 193 immersion lithography. Real time measurement of SE showed thickness increase when PR was immerged in water indicating swelling effect. From the temporal evolution we could observe its reaction-limited behavior. Meanwhile, IE could identify the modification of PR surface by contact of water even for a short period of a second.

• Journal of Applied Reliability
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• v.17 no.1
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• pp.28-37
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• 2017

Purpose: This paper proposes a procedure that may infer and identify interaction failures in a module. Methods: In design FMEA, we defined an interaction model between components and proposed a method for selecting a single component by using the standard specification classification table and four methods for choosing the related components. We also introduced the function tree for function and requirement characteristic analysis and proposed utilization of standard stress lists and 1st and 2nd stress analysis tables to determine the effect the stress analysis has on interactions. Finally, the interaction mechanism diagram was proposed and used to infer the failure mechanism. Process FMEA also established procedures in a similar way. Results: We established a procedure for predicting the failure mode due to interaction between components based on Company A's multi-step FMEA procedure. Conclusion: By applying the proposed interaction FMEA procedure to the development model, we were able to confirm the effect of the new derivation on the failure mode of interaction, which was not predicted by the existing FMEA.

• Journal of Families and Better Life
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• v.6 no.1
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• pp.131-148
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• 1988

The purpose of this study is to find out influential variables related to Home Management Behavioral Pattern. This study focuses on the following aspects: 1) to find out which variables of family environmental variables(ie, home makers' age, level of education, duration of marriage, number of children, home makers' employment, socioeconomic status) of psychological variables(ie, family communication the marital happiness) have significant effect on home management behavioral patterns. 2) to find out which variables of family environmental variables have significant effects on family communication and the marital happiness. 3) to identify the relationship between home management behavioral patterns and psychological variables. 4) to find out variables which have independently significant effects on home management behavioral patterns.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.902-903
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• 2015

현재 세계는 각종 에너지에 대한 연구가 치열하게 진행되고 있는 가운데 각 기계들의 에너지 효율등급이 엄격하게 규제되고 있다. 전동기 분야에서는 사용 용도에 따라서는 영구자석을 쓰지 않는 유도기가 주목을 받았다. 하지만 유도전동기는 가공이 쉽지 않고 동일 사이즈에서 출력이 동기 릴럭턴스 전동기(Synchronous Reluctance Motor; SynRM)보다 낮기 때문에 현재 국내외 전동기 시장에서는 SynRM이 주목받고 있으며 현재 많은 연구가 진행되고 있다. 본 논문은 30kW급 팬 부하용 SynRM 설계에 관해 논문이다. 기존에 사용되었던 유도 전동기를 대체하기 위해 전동기의 자속장벽의 형상에 따라서 어떠한 효과가 있는지에 대해 연구하고 앞으로의 SynRM의 회전자 형상 설계 방법을 제시한다.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1095-1096
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• 2006

Configuration management plays a key role in systems engineering process for any project from earlier stage of development. It consists of five major activities, ie., configuration management planing, configuration identification, configuration control, configuration status accounting and configuration verification and audit, and is essential to control system design development and operation throughout entire life cycle of the system development. And it is directly associated with other part of systems engineering management, ie., technical data management which provides traceability of important decisions and changes during development. In this paper, we describe how to apply CASE(Computer-aided Systems Engineering) tool-Cradle for the configuration management to achieve effectiveness of City Train Standard Specification Management process.