• Journal of the Korean Society for Precision Engineering
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• v.17 no.2
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• pp.114-120
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• 2000

Fossil power plant availability is significantly affected by gradual degradations of equipment as operation of the plant continues. It is quite important to determine whether or not to replace some equipment and when to replace the equipment. Performance calculation and analysis can provide the information. Robustness in the performance calculation can be increased by using verification ＆ validation of measured input data. We suggest new algorithm in which estimation relation for validated measurement can be obtained using correlation between measurements. Input estimation model is obtained using design data and acceptance measurement data of domestic 16 fossil power plant. The model consists of finding mostly correlated state variable in plant state and mapping relation based on the model and current state of power plant.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.5
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• pp.1068-1072
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• 2011

Hydrogen Fuel Cell Vehicle(HFCV) is system that uses electrical energy of fuel cell stack to main power source, which is different system with other vehicles that use high-voltage, large-current. Isolation performance of this system which is connected with electrical fire and electrical shock is important point. Isolation resistance of electric installation is divided according to working voltage, it follows criterion more than $100{\Omega}$/VDC (or $500{\Omega}$/VAC) about system operation voltage in a hydrogen fuel cell vehicle. Although measurement of isolation resistance in a hydrogen fuel cell vehicle is two methods, it uses mainly measurement by megger. However, the present isolation resistance measurement system that is optimized to use in electrical facilities is unsuitable for isolation performance estimation of a hydrogen fuel cell vehicle because of limit of maximum short current and difference of measurement resolution. Therefore, this research developed the isolation resistance measurement system so that may be suitable in isolation performance estimation of a hydrogen fuel cell vehicle, verified isolation performance about known resistance by performance verification of laboratory level about developed system, and executed performance verification through comparing results of developed system by performance verification of vehicle level with ones of existing megger. Developed system is judged to aid estimation and upgrade of isolation performance in a hydrogen fuel cell vehicle hereafter.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.3
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• pp.43-49
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• 2015

This paper describes the design of a forged fitting form to acquire a method of product design measurement by target measurement standards. The pipefitting connects each pipe and combines seals and nipples with the pipes normally. Therefore, the section combined with the fitting pipe was measured by a 3D scanner, and the acquired measurement and the design measurement were obtained after modification of the forged fitting pipe by that standard. Moreover, the accuracy of the model was verified through leakage testing of the oil and verification of the design measurement for accuracy decisions on the design measurement after modification of the product.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.7
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• pp.1642-1653
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• 1996

This paper covers feature extraction for automatic handwritten signature verification. Several major feature selection techniques are investigated from a practical perspective to realise an optimal signature verification system, and customised feature set selection based on set-on-set distance measurement is presented. The experimental results have proved the proposed methods to be efficient, offering considerably improved verification performance compared to conventional methods. Also, they dramatically reduce the processing complexity in the verification system.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.8
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• pp.1409-1417
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• 2003

In the 21st century, the concept of remote design and manufacture is strongly required in manufacturing processes to reduce cost and time-to-market. The objective of this paper is the development of an internet-based dimensional verification system for reverse engineering. An inspection client can register measurement data at the developed web server. Collaborators related to the development of a new product can confirm geometrical form from measurement data, check dimensional information and mark up the important parts, as well as make a statement of their views through the Internet. The developed system is realized through the ActiveX-Server architecture. Functions of the dimensional verification module are constructed as ActiveX by using the visual C＋＋ and OpenGL. The usefulness of the developed system is confirmed through a case study.

• Journal of Information Technology Services
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• v.11 no.1
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• pp.239-246
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• 2012

The user increases around the WiBro and in which the mobile broad band service is the wireless internet base technology HSDPA, that is the cellular phone foundation technique, and moreover the issue about the user effective quality guarantee emerges but the quality control of the wireless network is the incomplete actual condition. Therefore, the reliability verification according to the development of the system for the performance measure for the continued wireless data service and it and evaluation are needed for the quality control. In this paper, the wireless data service quality measurement system was implemented with the design. The same test environment as the existing network performance measurement program was built for the reliability verification of the embodied device for measuring quality and evaluation and the cost performance was performed. It could confirm that design and embodied wireless data service quality measurement system operated accurately in this paper through the quality measure result value analysis.

• Progress in Medical Physics
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• v.28 no.3
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• pp.111-121
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• 2017

Verification of dose distribution is an essential part of ensuring the treatment planning system's (TPS) calculated dose will achieve the desired outcome in radiation therapy. Each measurement have uncertainty associated with it. It is desirable to reduce the measurement uncertainty. A best approach is to reduce the uncertainty associated with each step of the process to keep the total uncertainty under acceptable limits. Point dose patient specific quality assurance (QA) is recommended by American Association of Medical Physicists (AAPM) and European Society for Radiotherapy and Oncology (ESTRO) for all the complex radiation therapy treatment techniques. Relative and absolute point dose measurement methods are used to verify the TPS computed dose. Relative and absolute point dose measurement techniques have a number of steps to measure the point dose which includes chamber cross calibration, electrometer reading, chamber calibration coefficient, beam quality correction factor, reference conditions, influences quantities, machine stability, nominal calibration factor (for relative method) and absolute dose calibration of machine. Keeping these parameters in mind, the estimated relative percentage uncertainty associated with the absolute point dose measurement is 2.1% (k=1). On the other hand, the relative percentage uncertainty associated with the relative point dose verification method is estimated to 1.0% (k=1). To compare both point dose measurement methods, 13 head and neck (H&N) IMRT patients were selected. A point dose for each patient was measured with both methods. The average percentage difference between TPS computed dose and measured absolute relative point dose was 1.4% and 1% respectively. The results of this comparative study show that while choosing the relative or absolute point dose measurement technique, both techniques can produce similar results for H&N IMRT treatment plans. There is no statistically significant difference between both point dose verification methods based upon the t-test for comparing two means.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.254-259
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• 2005

In this study, measurement of thermal conductivity of multilayer thin dielectric film has been conducted via differential 3$\omega$ method. Also, verification of differential 3$\omega$ method has been accomplished with various proposed criteria. The target film for measurement is 300 nm silicon dioxide and this thin film is covered with various thicknesses of upper protective layer. The upper protective layer is inserted between the target film and the heater line for purpose of electrical insulator or anti-oxidation barrier since the target film may be a good electrical conductor or a well-oxidizing material. However, the verification of differential 3$\omega$ method has not been conducted. Thus we have shown that the measurement of thermal conductivity of thin films with upper protective layer via differential 3$\omega$ method is verified to be reliable as long as the proposed preconditions are satisfied. Experimental results show that the experimental errors tend to increase with aspect ratio between upper protective layer thickness and width of the heater line due to heat spreading effect.

• Current Optics and Photonics
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• v.1 no.5
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• pp.500-504
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• 2017

In this paper, we developed a temperature measurement system based on an infrared temperature imaging module for thermal safety verification of a plasma skin treatment device (PSTD). We tested a pilot product of the low-temperature PSTD using the system, and the temperature increase of each plasma torch was well-monitored in real-time. Additionally, through the approximation of the temperature increase of the plasma torches, a certain limitation of the plasma treatment time on skin was established with the International Electrotechnical Commission (IEC) guideline. We determined an appropriate plasma treatment time ($T_{Safe}$ < 24 minutes) using the configured temperature measurement system. We believe that the temperature measurement system has a potential to be employed for testing thermal safety and suitability of various medical devices and industrial instruments.

• Transactions of the Society of Information Storage Systems
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• v.2 no.1
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• pp.85-90
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• 2006

In this study, measurement of thermal conductivity of multilayer thin dielectric film has been conducted via differential $3\omega$ method. Also, verification of differential $3\omega$ method has been accomplished with various proposed criteria. The target film for the measurement is 300 nm thick silicon dioxide which is covered with upper protective layer of various thicknesses. The upper protective layer is inserted between the target film and the heater line for purpose of electrical insulator or anti-oxidation barrier since the target film may be a good electrical conductor or a well-oxidizing material. Since the verification of differential $3\omega$ method has not been conducted yet, we have shown that the measurement of thermal conductivity of thin films with upper protective layer via differential $3\omega$ method is verified to be reliable as long as the proposed preconditions of the samples are satisfied. Experimental results show that the experimental errors tend to increase with aspect ratio between thickness of the upper protective layer and width of the heater line due to heat spreading effect.