• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1500-1503
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• 1997

In this paper a multiple channel EPD controller is developed which enables us to detect endpoints simultaneously in the plasma etching process operated in multiple etching chambers and its performance characteristic are investigated. for the accurate detectiion of endpoint the developed EDP controller was able to implement endpoint detectiions by integrating the existing EPD controllers with the techiques of artificial intellignet, to enhance its performance. The performance of the developed EPD controller was carried out by repeated experiments of endpoint detection in the acrual production line of semiconductor manufacturing. It's utility for endpoint detectiion was accurately evaluated in various etching process. The control capability of multiple etching chambers enhances its application compared with the existing one, and also increases the user utility os that the efficiency of operation was improved.

• 정보통신설비학회논문지
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• 제4권2호
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• pp.37-43
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• 2005

A simple scheduler satisfying the proportional fairness (PF) was introduced in wireless access networks and revealed that it can achieve a good compromise between total throughput and user fairness. Though it has received much attention for some time, its application was mainly restricted to the single channel systems. In this paper, we study how to implement the PF scheduler in the multi-channel environments such as OFDMA/TDMA. Besides the traditional PF-SC scheme, we propose a new PF-OPT scheme that is the genuine PF scheduler in a sense of maximizing the total log-utility of users. The simulation results show that PF-OPT gives large throughput under the heterogeneous subchannel statistics.

• 한국조경학회지
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• 제24권3호
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• pp.29-41
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• 1996

The purposes of this study were to develope some techniques which can be used in the landscape simulation process using PC based computer grahics. As a result, a couple of utilities were programmed in AutoLISP language. The one(DSLINE.LSP) is to digitize 2-dimensional structuer forms in the interactive mode considering error handling, and the other one (IMPOST.LSP) is for superimposing and visualizing the digitized plan data to 3-dimension solids & surfaces referring to topographic elevations of meshes in digital terrain model. By applying utilities to present site, the followings may be described. 1) The utility DSLINE.LSP for digitizing simplified building structure form were proved to be easy to input data of polygons including orthogonal edges by handling user coordinates system and checking invalid intersection and default colsing. 2) IMPOST.LSP utility for superimposing and visualizing tool were proved to be more complicated and speedy in calculating process compared with a practical application of modeling tool before rendering process in landscape simulation of built environment on topographic relief, on specially mesospace level of assessment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.309-312
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• 2002

For the purpose of more effective simulation of the utility interactive WPGS(Wind Power Generation System) the SWRW (Simulation method for WPGS using Real Weather condition) is used in this paper, in which those of three topics for the WPGS simulation. user-friendly method, applicability to grid-connection and the utilization of the real weather conditions, are satisfied. The simulation of the WPGS using the real weather condition including components modeling of wind turbine system is achieved by introducing the interface method of a non-linear external parameter and FORTRAN using PSCAD/EMTDC. The simulations of steady-state and transient-state are performed effectively by the introduced simulation method. The generator output and current supplied into utility can be obtained by the steady-state simulation, and THD can be achieved by analyzing the results as well. The transient - state of the WPGS can be analyzed by the simulation results of over cut-out wind speed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.276-279
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• 2004

The purpose of this paper is to describe and demonstrate how a utility-connectable inverter for photovoltaic or fuel-cell applications can be well modeled using PSCAD/EMTDC. In this paper, a single-phase IGBT inverter using SPWM is modeled. Simple voltage magnitude and phase controls are implemented using PSCAD's Pl controller, PLL, and a 'user defined' component called Modulo (found in their extensive collection of example circuits). The circuit model also takes advantage of PSCAD's interpolated firing pulse option, which provides improved simulation results by preventing errors from being introduced when switches fire between time simulation steps. Additionally, SCAD's Online Frequency Scanner for FFT is utilized for a demonstration of PSCAD's frequency-domain analysis capabilities.

• 한국문헌정보학회지
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• 제35권3호
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• pp.173-189
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• 2001

This paper presents a framework for observable behavior that can be used as a basis for user modeling, and it reports the results of a pair of user studies that examine the joint utility of two specific behaviors. User models can be constructed by hand, or they can be teamed automatically based on feedback provided by the user about the relevance of documents that they have examined. By observing user behavior, it is possible to obtain implicit feedback without requiring explicit relevance judgments. Four broad categories of potentially observable behavior are identified : examine, retain, reference, and annotate, and examples of specific behaviors within a category are further subdivided based on the natural scope of information objects being manipulated . segment object, or class. Previous studies using Internet discussion groups (USENET news) have shown reading time to be a useful source of implicit feedback for predicting a user's preferences. The experiments reported in this paper extend that work to academic and professional journal articles and abstracts, and explore the relationship between printing behavior and reading time. Two user studies were conducted in which undergraduate students examined articles or abstracts from the telecommunications or pharmaceutical literature. The results showed that reading time can be used to predict the user's assessment of relevance, that the mean reading time for journal articles and technical abstracts is longer than has been reported for USENET news documents, and that printing events provide additional useful evidence about relevance beyond that which can be inferred from reading time. The paper concludes with a brief discussion of the implications of the reported results.

• 정보과학회 컴퓨팅의 실제 논문지
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• 제22권12호
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• pp.675-680
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• 2016

다양한 모바일 기기와 모바일 플랫폼 기술의 발전에 따라 online social network(OSN) 사용자 수는 꾸준히 증가하고 있다. OSN 사용자들은 서비스를 통해 자유로운 의사소통과 정보 공유, 그리고 인맥 확대와 같은 사회적 활동을 할 수 있게 되지만, 이는 새로운 사용자 프라이버시 문제를 야기 한다. 이와 같은 사용자 프라이버시 침해 우려를 막기 위해 다양한 분산 OSN 아키텍처들이 소개되어 왔지만, 이 또한 기술적으로 사용자에게 자신의 데이터에 대해 완벽한 통제권을 부여하지 못한다. 본 논문은 OSN 사용자 정보에 대한 통제권의 부재를 해결하기 위해 personal data storage(PDS)를 사용한다. 또한 사용자 친구들을 각기 다른 프라이버시 레벨을 가지는 친구 그룹으로 그룹핑 한 뒤 각기 다른 사용자 친구 그룹들이 자신의 그룹 프라이버시 레벨에 맞는 사용자의 차등된 텍스트 데이터를 제공받도록 함으로써 사용자 프라이버시와 서비스 유틸리티 모두를 고려한 시스템 아키텍처를 제안하였다.

• 한국통신학회논문지
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• 제39C권7호
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• pp.538-545
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• 2014

본 논문은 다운링크 다중 선박 네트워크에서 동적으로 협력 전송(CoMP Transmission; Coordinated Multi-point Transmission)을 사용하는 유틸리티 함수를 도출하고 이를 기반으로 스케줄링 기법을 제안한다. 제안하는 스케줄링 기법은 수율과 공정성을 고려한 PF 형태의 유틸리티 함수를 최대화하기 위해서 매 프레임 협력적 전송 여부를 결정하고, 유틸리티 함수를 최대화하는 사용자를 선택한다. 특히 제안하는 유틸리티 함수 기반의 스케줄링 기법은 셀 경계 지역에 위치하는 사용자의 서비스 품질을 만족시키는 것을 목적으로 한다. 무선 환경에서 PF(Proportional Fair) 스케줄링을 사용할 때 제안한 유틸리티 함수를 기반으로 하는 스케줄링 기법의 성능을 평가한다. 모의실험을 통하여 제안하는 스케줄링 기법은 협력적 통신 네트워크와 비협력적 통신 네트워크를 동적으로 사용함으로써 전체 네트워크의 성능을 유지하면서 가장자리에 있는 선박의 성능을 향상시키는 것을 확인하였다.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2006년도 학술대회 1부
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• pp.970-975
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• 2006

There is a tradeoff between user's privacy and utility of context-aware services in ubiquitous computing environments. Many privacy models have been proposed to support the disclosure of personal information at different levels of detail, in ubiquitous computing environments. However, most of these models do not allow for explicit criteria to assess the benefit users are likely to reap by disclosing their personal information. In this paper, we propose an automated decision making mechanism that evaluates the "benefit of disclosure" for the users based on trust relationships between users and information requesters and manages the disclosure of user's personal information accordingly. Unlike other trust models, we do not regard the reputation of an information requester as sufficient to determine his/her trustworthiness. Instead, we represent trustworthiness as a function of information requester's reputation in the eyes of the user and his/her competence in a given context. To validate our mechanism, we apply it to context-aware healthcare application that monitors physiological condition of a user.

• 농촌지도와개발
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• 제4권1호
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• pp.201-209
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• 1997

The objective of this study were 1) to review concepts of user information satisfaction (UIS), 2) to analyze tools for measuring user information satisfaction, 3) to identify factors affecting information satisfaction. The study was carried out by the analysis of literatures related to information system. The construct of UIS has been operationalized in many different ways. Several studies employed single-item rating scales; such scales have been criticized as unreliable. Single-item scales also provide little information as to what the user finds dissatisfying(satisfying) and are thus of limited utility outside a research setting. Multiple-item UIS measures have become increasingly common. Generally, they are of two types. The first focuses on the information system product. With such diverse names as "system acceptance", "output quality", and "appreciation", these scales focus on the content of the information system and the manner in which the information is presented. The second type of multiple-item scale includes the organizational support for developing and maintaining the system as well as the system product itself. This type of instrument contains items concerned with training, documentation, development procedures, systems maintenance, etc., as well as items related to system content. Thus it provides an indicator of the overall quality of information services provided by an information service function. Generally, UIS measures have not been carefully validated. Recently, however, several rigorous attempts have been made to develop valid and reliable UIS measure.