• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.1
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• pp.90-98
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• 2016

Currently government certified test method for an automobile remanufactured products is insufficient. Thus many automotive parts in the remanufacturing market are lacking proper evaluation criteria and production of defective products are causing customer dissatisfaction. In this paper a power steering oil pump, which requires stringent manufacturing standards, is studied by the failure mode and effect analysis approach. The research suggested that the test criteria such as discharge flow characteristic test, tightness test, pulley run-out test, pressure switch operation test, low temperature test and rotation pressure durability test should be performed to evaluate the reliability of remanufactured power steering oil pumps. As a result of tests, the performance of remanufactured power steering oil pump satisfied the evaluation criteria of pressure switch operation test and low temperature test. However, the remanufactured power steering oil pump failed to satisfy the evaluation criteria on discharge performance test, tightness test and pulley run-out test. These performance evaluation tests proved the necessity of standard process for the remanufactured power steering oil pump.

• Journal of Auto-vehicle Safety Association
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• v.10 no.4
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• pp.33-39
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• 2018

Recently, the automobile industry has developed ADAS (Advanced Driver Assistance System) to prevent traffic accidents and reduce driver's driving burden. Among the ADAS, the LKAS (Lane Keeping Assistance System) is a support system for the convenience and safety of the driver, and the main function is to maintain the driving lane of the vehicle. LKAS is a system that uses radar sensor and camera sensor to collect information about the position of the vehicle in the lane and to support keeping the lane through control if necessary. In many countries, LKAS has already been commercialized and the convenience and safety of drivers have been improved. The international LKAS evaluation test procedure is being developed and discussed by standardization committees such as the ISO (International Organization for Standardization) and the Euro NCAP (New Car Assessment Program). In Korean, the LKAS test method is specified in the KNCAP (Korean New Car Assessment Program), but the evaluation method is not defined. Therefore, the LKAS test procedure that meets international standards and is suitable for domestic road environment is necessary. In this paper, development of LKAS test evaluation scenarios that meets international standards and considering domestic road environment, and the formula that can evaluate the result value after control as the relative distance of lane and the front wheel are suggested. And a comparative analysis was conducted to verify the validity of the suggested scenario and formula. The test evaluation was conducted using the vehicle equipped with the LKAS.

• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1616-1629
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• 2023

To quantify the conservatism of existing ASME strain-based evaluation methods for seismic loading, this paper presents very low cycle fatigue test data of elbows under various cyclic loading conditions and comparison of evaluation results with experimental failure cycles. For strain-based evaluation methods, the method presented in ASME BPVC CC N-900 and Sec. VIII are used. Predicted failure cycles are compared with experimental failure cycle to quantify the conservatism of evaluation methods. All methods give very conservative failure cycles. The CC N-900 method is the most conservative and prediction results are only ~0.5% of experimental data. For Sec. VIII method, the use of the option using code tensile properties gives ~3% of experimental data, and the use of the material-specific reduction of area can reduce conservatism but still gives ~15% of experimental data.

• Journal of Soil and Groundwater Environment
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• v.22 no.5
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• pp.98-104
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• 2017

Human Resources Development of Korea has been practicing performance evaluation for occupational qualification licences in environmental sectors that include water, air, and wastes management, but not soil. The purpose of the study was to improve overall quality of the national qualification test in the soil sector to better train applicants based on National Competency Standards (NCS), which is designed to emphasize site-specific conditions and knowledge. This study systematically analysed the current licence test in the soil sector with respect to qualification units, performance criteria, knowledge, techniques, and attitude as described in NCS. Furthermore, test evaluation was conducted to examine the validity of the revised licence test. The test results indicated the revised test method would bring positive outcomes to the related industry. Upon the reviews and amendments by the field experts, the result of this study could serve as a framework to the development of more robust and reliable licence test.

• Journal of Convergence Korean Medicine
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• v.3 no.1
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• pp.15-27
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• 2022

Objectives: This study was conducted to review the overall concept of nutritional evaluation of infants and young children. Methods: Literature search was done to study definition, method and importance of nutritional evaluation of infants and young children. Pubmed and Google scholarship were used in the research. Search words were 'Nutritional evaluation', 'infants' and 'young children'. Results: Nutrition evaluation is mainly used by physical measurement, clinical evaluation, dietary intake survey, and biochemical test depending on the age and disease. The treatment method for 治未病, which is a concept of korean medicine, and 健兒法 for treating the concept of weak children are considered to have very high applicability in solving various problems found through nutrition evaluation in korean medical approach. Conclusion: Infants and children are the fastest growing period of their lives, showing rapid growth in physical, and emotional development along with rapid brain growth. Therefore, inadequate nutrition during this period affects mental and physical growth and development not only during that period but also throughout life. Nutrition evaluation is divided into regular evaluation that includes children in all growing seasons and screening evaluation for problem solving, and follow-up nutritional evaluation that evaluates nutritional status in the long run. For each nutritional evaluation, evaluation is conducted by physical measurement, clinical evaluation, dietary intake survey, and biochemical test. By comprehensively interpreting them, nutritional status is determined. This study provides basic data on the proper nutrition evaluation method to identify and correct nutritional problems such as growth level, nutritional deficiency, and nutritional excess early.

• Journal of Power System Engineering
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• v.3 no.4
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• pp.51-56
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• 1999

The ultrasonic method, which is well known as nondestructive test method, is widely used to evaluate the material damage due to degradation. However, this method is just used for measuring the crack size and the thickness loss of the tube. The purpose of this study is to investigate the applicability of the ultrasonic technique for the evaluation of marine diesel engine exhaust valve and to suggest the correlations between the ultrasonic characteristics and valve degradation. From the evaluation of the results obtained, the technique of using the ultrasonic property was founds to be a efficient method to evaluate the degree of marine diesel engine exhaust valve by nondestructive test.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.3
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• pp.291-295
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• 2008

We have developed an evaluation technique for ratio errors of current transformer (CT) comparator by using the precise standard capacitors. By applying this technique for equivalent circuit of CT comparator evaluation system, we can obtain the calculated and measured ratio errors in the CT comparator. Thus we can evaluate ratio errors of CT comparator by comparing the calculated and measured ratio errors. Because this method requires only the standard capacitors, it is simple and easy method to reliability and accuracy maintenance of CT comparator. The method was applied to CT comparator under test with the ratio error ranges of $0{\sim}{\pm}10%$. The ratio error of the CT comparator under test theoretically obtained in this method are consistent with that measured for same CT comparator under test by using wide ratio error CT within an estimated expanded uncertainty (k = 2) in the overall ratio error ranges.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.8
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• pp.1948-1957
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• 1996

The conformance testing of communication protocol is the process to evaluate whether the protocol implemented is identified with standard specification. By evaluating how generated test cases detect many faults, it can be used with standard estimating efficiency of conformance testing. The method that evaluates the capability of fault coverage for test cases, has been researched by mathematical analysis and simulation. In this paper, we pointed out the problem of existing method and proposed new evaluation model of fault covergage for test case which generated by foult model. Also, we analyzed the results comparing to the existing evaluation method and proved its validity.

• Transactions of The Korea Fluid Power Systems Society
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• v.2 no.2
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• pp.1-7
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• 2005

For the reliability evaluation of the track drive unit(TDU), firstly, we analyzed the major failure modes through FMEA(failure mode & effects analysis), FTA(failure tree analysis), and 2-stage QFD(quality function deployment), and then quantitatively determined the priority order of test items. The Minitab analysis was also performed for prediction of life distribution and parameters of TDU by use of field failure data collected from 430 excavators for two years. In addition, we converted the fluctuation load in field conditions into the equivalent load, and for evaluation of the accelerated lift by the cumulative fatigues, the equivalent load is again divided into the fluctuation load by reference of test time. And then, by use of the test method in this paper, the acceleration factor(AF) of needle bearing inside planetary gear which is the most weakly designed part of TDU is achieved as 5.3. This paper presents the quantitative selection method of test items for reliability evaluation, the determination method of the accelerated life test time, and the method of non-failure test time based on a few of samples. And, we proved the propriety of the proposed methods by experiments using a TDU for a 30 ton excavator.