• 전기학회논문지
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• 제63권5호
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• pp.713-718
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• 2014

DC urban railway power system consists of DC power network and AC power network. The DC power network supplies electric power to railway vehicles and the AC power network supplies electric power to station electric equipment. Recently, because of power consumption reduction and peak load shaving, intelligent measurement of regenerative energy and renewable energy adapted on DC urban railway is required. For this reason, DC smart metering system for DC power network shall be developed. Therefore, in this paper, DC voltage sensor, current sensor, and DC smart meter were developed and evaluated by performance test. DC voltage sensor was developed for measuring standard voltage range of DC urban railway, and DC current sensor was developed as hall effect split core type in order to install in existing system. DC smart meter possesses function of general intelligent electric power meter, such as measuring electricity and wireless communication etc. And, DC voltage sensor showed average 0.17% of measuring error for 2,000V/50mA, and current sensor showed average 0.21% of measuring error for ${\pm}2,000V/{\pm}4V$ in performance test. Also DC smart meter showed maximum 0.92% of measuring error for output of voltage sensor and current sensor. In similar environment for real DC power network, measuring error rate was under 0.5%. In conclusion, accuracy of DC smart metering system was confirmed by performance test, and more detailed performance will be verified by further real operation DC urban railway line test.

• KIEAE Journal
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• 제9권5호
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• pp.63-68
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• 2009

As with the disappearance of a living room window due to the trend in apartment housing construction that prefers a larger, expanded living room, the sound insulation performance of the balcony window is becoming an important factor to determine the level of indoor noise at an apartment unit. Considering that the indoor noise inside an apartment unit is mandated by law at or below 45dB(A), the balcony window is increasingly assuming an even more important role. Sound insulation performance of the window was measured by examining differences in data involving varying angles of incidence of the sound source as obtained from the same balcony window. Also, acoustic intensity measuring was performed at and around the window to determine its sound insulation quality. Results of measuring on the sound source's angles of incidence indicated that the performance showed some differences in lower frequency ranges, though with no significance. Intensity measuring results showed that the sound insulation performance was reduced near the connection part of the window and the window frame.

• 한국기계가공학회지
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• 제16권3호
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• pp.69-75
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• 2017

There are two types of expensive measuring instruments currently on the market shape measurement and roundness measurement instruments. As they are very expensive, from tens of millions to more than 200 million won, buying them is economically burdensome for small companies or individuals. Therefore, in order to integrate the shape and roundness measurements into a single transfer device, this study aimed to reduce the trial and error by 3D modeling and simulation, and we confirmed the feasibility of operation. Based on these outcomes, a prototype hybrid measuring instrument was fabricated. As a result of performance evaluation and comparative evaluation, we verified the feasibility of implementation and application of the hybrid measuring instrument.

• 한국정밀공학회지
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• 제26권3호
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• pp.47-54
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• 2009

In the manufacturing industry, there has been a significant increase in the use of coordinate measuring machines(CMM). In this paper, the sources of CMM measurement performance are discussed. The effects of workpiece position, length and orientation are analyzed by using the design of experiments. Both a fractional factorial design and a factorial design are employed to conduct the experimental study. The analysis of variance is performed to determine the significance of factors in the experiment and regression analysis is applied to make the measurement approximate model. The results show that position along the Z axis, length and orientation affect the CMM measurement performance.

• 경영과학
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• 제28권1호
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• pp.75-90
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• 2011

In B2B e-Commerce market, many companies used in B2B e-Commerce Guarantee Service. Guarantee service raised the stability of collect debts for seller, and made purchase fund for buyer. In 2001, The first year of implementation, B2B e-Commerce Guarantee Cost was just a 19 billion, but in 2008 was significantly increased a 3 trillion 982 billion. In previous studies, however, there was no research on performance management. This study focus on design of KPI weighting for measuring performance of B2B e-Commerce Guarantee Intermediary Service. Through analysis for 'B2B e-Commerce Guarantee Intermediary Service', the study selected KPI and made the KPI weighing. the process of designing a KPI weighting is 5 phase. This study suggests the standard of measuring performance and guidelines on the focus management of KPI in B2B e-Commerce Guarantee Service.

• 한국정보과학회논문지:소프트웨어및응용
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• 제31권8호
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• pp.1043-1053
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• 2004

컴포넌트 기반 소프트웨어에서는 사용될 컴포넌트의 성능이 개발되는 소프트웨어의 품질 확보에 있어서 매우 중요한 요소이다. 컴포넌트 성능에는 흔히 컴포넌트 모델이나 미들웨어에 종속적인 성능측정 도구가 이용된다. 이러한 성능측정 방법에서는 소프트웨어의 개발환경이 변경될 경우 측정 도구도 함께 수정되어야 한다는 문제점을 가지고 있다. 또한, 여러 가지 다른 모델의 컴포넌트들을 한 시스템으로 통합하는 경우에도 유사한 어려움이 존재한다. 본 논문은 이러한 문제에 대한 해결 방법으로 컴포넌트 모델이나 미들웨어에 독립적인 성능측정 방법을 제안한다. 제안된 방법은 미들웨어에 공통적으로 적용 가능한 성능측정기 모델에서 특정 미들웨어를 위한 성능측정기 모델로의 모델변환 과정을 통해 성능데이타간의 상호운용성을 보장한다. 이 방법을 이용하면 동일한 컴포넌트 모델에 따른 컴포넌트들뿐만 아니라 서로 다른 컴포넌트 모델을 기반으로 하는 컴포넌트들에 대한 성능측정이 가능하다.

• 한국비블리아학회지
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• 제19권1호
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• pp.61-87
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• 2008

도서관통계와 평가의 관련성이 국제표준안, 업무활동 영역, 항목간의 유사성 면에서 깊고, 불가분의 관계 속에 있음에도 한국 대학도서관의 통계와 평가는 생산단계 및 활용 면에서 전혀 연계되어 있지 않다. 이를 증명하기 위하여 국제표준, 통계데이터를 살펴 두 항목간에 연계적 상관관계를 살펴보아 정량적 데이터의 45%정도의 중복도가 있음을 밝혔다. 반면 기존의 국내 통계 항목과 평가 항목간에는 14-26%의 관계가 있으며, 새로이 연구 개발된 대학도서관통계 실용안에서는 상당히 발전된 관계성을 발견하였으며, 반면 상당한 특정성도 발견되었다. 이제 대학도서관통계 온라인시스템 개발단계에서 통계시스템의 목적 외에 평가시스템정보를 제공한다는 면을 고려하여 항목간의 포괄적 정보가 제공되도록 개발하는 것이 필요하다.

• 경영과학
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• 제26권1호
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• pp.137-159
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• 2009

An organizational performance measurement practice is a function of performance measurement system and performance management system they are currently employing, and its quality is determined by evaluating the followings in a comprehensive manner: first, if they are measuring right things; second, if they are measuring in a right way; third, if they are actively facilitating a process of data collection, structuring, analysis, interpretation, and dissemination; and fourth, if they are using performance measurement results for the primary purposes of performance measurement. This study proposes a diagnostic framework for evaluating the performance measurement practices of public broadcasting which include the qualities of performance measurement and performance management, and develop a structured questionnaire for that purpose. The framework proposed in this study does not serve only as a useful tool for public broadcasting to revise their respective performance measures and performance measurement systems, but it also make their respective performance measurement practices a strategic management tool as well as an operational management one.

• 한국정보시스템학회지:정보시스템연구
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• 제20권3호
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• pp.161-186
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• 2011

To date, SCM research has mainly focused on the effects of controlled variables on SCM success and emphasized adoption strategies and critical success factors. Consequently, the effects of more uncontrolled variables such as partnership between SCM partners have been largely ignored. The purpose of this study, therefore, is to examine the effects of both controlled variables and uncontrolled variables on SCM performance through affecting RTE characteristics. The six factors examined in this study include Quality of information, partnership quality, Forecasting, Agility, Visibility, and SCM performance. In this study, SCM Performance was divided into three categories: Quality Performance, Cost Performance, Delivery Performance. All factors were examined from the perspective of part suppliers. The results of this study can be summarized as follows. First, SCM information quality positively affected SCM partnership quality, Forecasting, Agility, Visibility. Second, SCM partnership quality positively affected Forecasting, Agility. But, SCM partnership quality showed no significant effect on Visibility. Third, Forecasting had a significant impact on SCM performance. According to the detailed result of measuring SCM performance with Quality Performance, Cost Performance, Delivery Performance, although Forecasting affects Cost Performance, Delivery Performance directly, it does not affect Quality Performance directly. Fourth, Agility also had a significant impact on SCM performance. According to the detailed result of measuring SCM performance, Agility has significant impact on Quality Performance, Cost Performance, Delivery Performance. Fifth, Visibility, as expected, had a significant impact on SCM performance. According to the detailed result of measuring SCM performance, Visibility has significant impact on Quality Performance, Cost Performance, Delivery Performance.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.299-302
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• 2000

Various types of measuring devices are used for reverse engineering and inspection in different fields of industry such as automotive, aerospace, computer graphics, and home appliance. In order to measure a part easily and efficiently, it is important to select appropriate measuring device considering the characteristics of each measuring machine and part information. In this research, an optimal measuring device selection system using neural networks is proposed. There are two major steps: Firstly, the measuring information such as curvature, normal, type of surface, edge, and facet approximation is extracted from the CAD model. Second, the best suitable measuring device is proposed using the neural network system based on the knowledge of the measuring parameters and the measuring resources. An example of machine selection is implemented to evaluate the performance of the system.