• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.5
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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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• v.9 no.5
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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.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.3
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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.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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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.

• Korean Management Science Review
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• v.28 no.1
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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.

• Journal of KIISE:Software and Applications
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• v.31 no.8
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• pp.1043-1053
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• 2004

The performance of a component can significantly influence the overall performance of the system being developed in the component based software development. Existing performance measurement tools for components are often built specific to the component model or middleware. One disadvantage of this approach is that when the system is moved to a new platform during the life-cycle of the system, the measurement tools also need to be adapted. A similar problem is observed when components built for different platforms are integrated with a new integration technology like Web Services. This paper presents a new model for measuring component performances, which is independent of particular component models or middleware. This method presents a interoperability for each performance data by model transformation process from middleware independent performance measuring models to middleware dependent performance measuring models. Our model allows objective performance data to be obtained that can be used to compare performances of components based on different component models or middleware platforms.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.19 no.1
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• pp.61-87
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• 2008

There is a close relationship between indicators of statistics and performance measurement in international standards, working sections and the data items similarity in academic libraries. However, this co-relationship between statistics and measuring performance in the Korean academic library is not related to each other in terms of designing or usage. In order to prove this, the co-relationship between indicators of statistics and performance measurement has been researched based on applications of international standards and data. The international result shows 45% of overlapping in statistical and measuring performance indicators. However, there is only 14 to 26% of the co-relationship in existing statistics and performance measurement in Korea. A considerable improvement of the co-relationship between the indicators has newly been found. Therefore, in developing online system of academic library statistics, it is essential to provideinclusive information between indications of statistics and performance measurements.

• Korean Management Science Review
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• v.26 no.1
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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.

• The Journal of Information Systems
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• v.20 no.3
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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.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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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.