• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.4
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• pp.107-116
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• 2006

The international standard to determine grounding conductor size can be applied for a wide range of items because it includes the specific physical characteristics, but it has a problem where the numerical formula is complicated. However the JIS and domestic standard numerical formula are simple but have many constraints. The new grounding conductor size selecting method is necessary in order to solve such problems. Therefore, in this study, we suggested an improved method for selecting the grounding conductor size and simple numerical formula with a numerical formula control modeling. and we verified reliability of paper used case study.

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.875-880
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• 2006

A new, simple and fast flow injection analysis (FIA) method has been developed for the indirect determination of nitrite. The proposed indirect automatic method is based on the oxidation of nitrite to nitrate using a lead(IV) dioxide oxidant microcolumn where the flow of the sample through the microcolumn reduces the $PbO_2$ solid phase reagent to Pb(II), which is measured by flame atomic absorption spectrometry. The absorbance of Pb(II) are proportional to the concentration of nitrite in the samples. The calibration curve was linear up to 30 mg $L ^{-1}$, with a detection limit of 0.11 mg $L ^{-1}$ for a 400 mL injected sample volume and a sampling rate of about 80 $h ^{-1}$. The results exhibit no interference from the presence of large amounts of ions. The developed procedure was found to be suitable for the determination of nitrite in foodstuffs and wastewaters. A relative standard deviation better than 0.9% was obtained in a repeatability study. The reliability of the method was established by parallel determination against the standard method.

• Journal of Technologic Dentistry
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• v.37 no.4
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• pp.285-293
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• 2015

Purpose: The following study analyzes the mediating effects of professionalism on the relationship between major selection conviction and career decision level of dental technology students. It is to be used as basic data for improvement of the students' career decision level and an effective way to train professionals of the colleges. Methods: The survey was conducted on dental technology students. The collected data was analyzed by the statistical program SPSS 18.0. The results were analyzed by reliability, frequency, multiple-way ANOVA, correlation, multiple regression. To test for significance on each item, p<0.05 has been decided as a standard. Results: The analysis shows that the students' age and clinical practice experience bring a significant difference in major selection conviction, career decision level and professionalism. Professionalism has been found to bring significance mediating effects in relation to major selection conviction and career decision level. Conclusion: To improve the quality and pride as a professional as well as satisfaction with major selection can be expected to raise the standard of the students' career decision level.

• Journal of the Korean Home Economics Association
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• v.36 no.5
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• pp.89-106
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• 1998

Standard contsacts are drafted by one side only and therefore naturally favour that party. The other party must either adhere to those terms or abandon the transaction entirely. Accordingly the terms in these contracts tend to by quite harsh, especially so in consumer transactions. The objectives of this study are to examine the degree of consumer knowledge practical use, experience of consumer problems on service contract terms and to investigate the factors which influence on the degree of experience of consumer problems related the contract terms. The data used in this empirical study included 685 consumers experienced transactions with the terms in the last two years in Seoul. Statistics used for data analysis ere Reliability, Frequencies, Means, Standard Deviation and Multiple Regression Analysis. The conclusions can be summarized as follows. 1) Actually, consumers experienced many problems related the service-contract terms, despite regulation of unfair contract terms. 2) The level of education and purchasing experience variables have affected positively to the level of consumer problem experiences related the contract terms. 3) The effect of trend and characteristics of contract terms are variables with the type of contract terms. Therefore the regulation of the contract terms have to by differently enforced according to the type of contract terms.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.608-611
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• 2003

Performance assessment was introduced to improvement of self-directed learning and method of assessment for differenced learning as the seventh educational curriculum is enforced. Performance assessment is overcoming limitation about problem solving ability and higher thinking abilities assessment that is problem of a written examination and get into the spotlight by way for quality of class and school normalization. But performance assessment has problems about possibilities of assessment fault by appraisal, fairness, reliability, and validity of grading, ambiguity of grading standard, difficulty about objectivity security etc. This study proposes fuzzy performance assessment system to solve problem of the conventional performance assessment. This paper presented an objective and reliable performance assessment method through fuzzy reasoning, design fuzzy membership function and define fuzzy rule analyzing factor that influence in each sacred ground of performance assessment to account principle subject. Also, performance assessment item divides by formation estimation and subject estimation and designed membership function in proposed performance assessment method. Performance assessment result that is worked through fuzzy performance assessment system can pare down burden about appraisal's fault and provide fair and reliable assessment result through grading that have correct standard and consistency to students.

• Aerospace Engineering and Technology
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• v.6 no.1
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• pp.222-229
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• 2007

Environmental tests should be carried out to show that design performance is in an operational condition in an actual operational environment to assure maintainability and reliability. Aero-products electromagnetic compatibility tests are performed mainly for the individual parts and Specifications MIL-STD-461E and RTCA DO-160E are developed for the military and commercial parts tests respectively. The MIL-STD-461E which is a military environmental test standard is targeting all munitions and that user can apply by selecting applicable requirements from this specification. On the other hand, requirements are applied exclusively for the Avionics Equipments in commercial test standard.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.4
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• pp.314-318
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• 2013

Tests and evaluations following the U.S. MIL-HDBK/STANDARD were successfully conducted to assure the performance of the air-to-surface guidance kit which was developed first in Korea. Various ground tests confirmed the operation capability and reliability of the guidance kit, and flight tests proved very good mid-range gliding performance and accuracy of the gliding bomb which was a general purpose bomb with the guidance kit.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.918-922
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• 2007

Aero-pulsation noise, generally caused by geometric asymmetry of a rotating device, is considerable source of annoyance in passenger cars using the turbocharged diesel engine. Main source of this noise is the compressor wheel in the turbocharger system, and can be reduced by after-treatment such as silencers, but which may increase the manufacturing cost. More effective solution is to improve the geometric symmetry over all, or to control the quality of components by sorting out inferior ones. The latter is more effective and reasonable than the former in view of manufacturing. So, an appropriate discrimination method should be needed to evaluate aero-pulsation noise level at the production line. In this paper, we introduce the accurate method which can measure the noise level of aeropulsation and also present its evaluation criteria. Besides verifying the reliability of a measurement system - a rig test system -, we analyze the correlation between the results from rig tests and those from vehicle tests. The gage R&R method is carried out to check the repeatability of measurements over 25 samples. From the result, we propose the standard specification which can discriminate inferior products from superior ones on the basis of aero-pulsation noise level.

• Current Industrial and Technological Trends in Aerospace
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• v.7 no.1
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• pp.119-127
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• 2009

There have been about 450 atomic frequency standards (or atomic clocks) launched into orbit for the use on communications and scientific payloads since 1970's. GPS satellites carry on-board Rubidium and Cesium atomic frequency standards which are utilized for the precise positioning and timing. The evolving technologies of space qualified atomic frequency standards have enhanced in the performance, reliability, and lifetime of satellites. In this paper we describe the fundamentals and performance of the atomic frequency standards, and introduce the atomic frequency standards which are presently on-board various satellites systems. We also present the GPS time scale and its applications.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.6
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• pp.1139-1144
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• 2019

A calibration system for diagnosing and confirming the performance of precision measuring instruments minimizes the risk of misjudgment of calibration resulted by complying with international standard requirements in order to ensure the reliability of calibration results. This paper uses a proposed calibration system suitability assessment and a guard-band technique through an analysis of uncertainty factors when it is impossible to acquire and operate high-performance equipment at a calibration laboratory, and proposes an optimized test limit output model substituting performance standards. The proposed method provides an optimized test standard to meet the quantitative evaluation criteria of the calibration system and the probability of false acceptance risk required by international standards.