• The Journal of Fisheries Business Administration
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• v.38 no.1 s.73
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• pp.97-113
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• 2007

This study attempts to suggest a new approach of the the determination of location and range of fishing ground in the coastal vessel fishery using the anaiysis of variance(ANOVA) and least significant difference test(LSD test) in statistics. The important result of the empirical study is that there is no significant difference in fisfishing ground based on between fishermen's argument and spot investigation. But there is stastitically significant difference in fisfishing ground based on between fishermen's argument and the official documents of fishing records for past three years. The results suggest us that there exists a possibility of misuse of tax free oil providied for subsidizing fisheries. But because of the range limitation of data, it is impossible for us to generalize the above results.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.1
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• pp.72-78
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• 2009

We have developed a current range extension method to obtain the ratio error and phase displacement of a current transformer (CT) by using absolute evaluation method and two different CTs. The method was applied to CTs under test with the current ratios in the range of 5,000 A / 1 A - 20,000 A / 1 A. The ratio error and phase displacement of the CT under test obtained in this study are consistent with those measured at the national institute in Germany using the same CT under test within an expanded uncertainty (k = 2) in the overall current ratios.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.177-180
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• 2006

It is essential for engine design and establishment of test program to assign an appropriate performance range of liquid propellant rocket engine(LRE). The present study surveys the operation and qualification test range of LRE developed in Japan, United States, Europe and Russia.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.4
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• pp.398-403
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• 2006

This paper describes the evaluation of the long duration current impulse withstand characteristics of ZnO blocks for high voltage surge arresters. Four ZnO varistors were manufactured with the general ceramic production method and the long duration current impulse withstand test, electrical uniformity evaluation test and microstructure observation were performed. All varistors exhibited high density, which was in the range of $5.42{\sim}5.46g/cm^3$. In the electrical properties, the reference voltage of samples was in the range of $5.11{\sim}5.25\;kV$ and the residual voltage was in the range of $8.314{\sim}8.523\;kV$. In the long duration current impulse withstand test, sample No.2 and No.3 failed at the 2nd and 4th shot of series impulse currents, respectively, but the rest survived 18 shots during the test. Before and after this test, the variation ratio of the residual voltage of samples survived was below 0.5 %, which was in the acceptance range of 5 %. According to the results of the test, it is thought that if the soldering method is improved, ZnO varistors would be possible to apply to the high voltage arresters like the station class and transmission line arresters in the near future.

• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1470-1476
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• 2019

The nuclear power plants in South Korea have been designed in accordance with the U.S. Regulatory Guide 1.60 (R.G 1.60) design spectrum of which the peak frequency range is 2-10 Hz. The characteristics of the earthquakes at the Korea nuclear power plant sites were observed to be closer to that of Central and Eastern United States (CEUS) than the R.G 1.60, which is a lower amplification in a low frequency range, and a higher amplification in a high frequency range. The possibility of failure for sensitive power plant components in the high frequency range has been considered and evaluated. In this study, in order to improve the reliability of nuclear plant and administrative control procedures, seismic tests of an emergency diesel generator (EDG) were conducted using a shaking table under both high and low frequency ranges. From the tests, oil/lubricant leaks from the bolt connections, the fuel filter and the fuel inlet were observed. Therefore, the check list of nuclear plant components after an earthquake should include bolt connections of EDG as well as anchor bolts.

• Journal of Korean Physical Therapy Science
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• v.13 no.4
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• pp.27-34
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• 2006

Purpose : The purpose of this study is to prove the increasing range of motion of joint to the patients of adhesive capsulitis of the shoulder applied the gliding-mobilization. Subjects and methods : The subjects are patients of adhesive capsulitis of the shoulder who have limited range of motion due to capsular pattern on the shoulder. The subjects are volunteer patients without a history of neuromuscular problems and randomly distributed into two groups. 15 experimental subjects(4 male, 11 female) received therapy with gliding-mobilization applied on limited shoulder joint and a second group with 15 control subjects(6 male 9 female) was treated by physiological passive range of motion therapy. The data were analyzed with paired t-test to determine striking differences depending on the course of treatment. Result : 1) In the group treated by gliding-mobilization the range of motion in shoulder flexion was increased in accordance to the course of treatment, and paired t-test showed striking differences(p<.05). 2) The range of motion in shoulder extension was increased in accordance to the course of treatment, and paired t-test showed striking differences(p<0.05). 3) The range of motion in shoulder abduction was increased with serise of treatment, and paired t-test showed striking differences(p<0.05). Conclusion : The gliding-mobilization increases the range of motion of the patient of adhesive capsulitis of the shoulder.

• Journal of the Korea Safety Management & Science
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• v.16 no.2
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• pp.43-52
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• 2014

In weapon systems development, live fire tests have been frequently adopted to evaluate the performance of the systems under development. Therefore, it is necessary to ensure safety in the test ranges where the live fire tests can cause serious hazards. During the tests, a special care must be taken to protect the test and evaluation (T&E) personnel and also test assets from potential danger and hazards. Thus, the development and management of the range safety process is quite important in the tests of guided missiles and artillery considering the explosive power of the destruction. Note also that with a newly evolving era of weapon systems such as laser, EMP and non-lethal weapons, the test procedure for such systems is very complex. Therefore, keeping the safety level in the test ranges is getting more difficult due to the increased unpredictability for unknown hazards. The objective of this paper is to study on how to enhance the safety in the test ranges. To do so, an approach is proposed based on model-based systems engineering (MBSE). Specifically, a functional architecture is derived utilizing the MBSE method for the design of the range safety process under the condition that the derived architecture must satisfy both the complex test situation and the safety requirements. The architecture developed in the paper has also been investigated by simulation using a computer-aided systems engineering tool. The systematic application of this study in weapon live tests is expected to reduce unexpected hazards and test design time. Our approach is intended to be a trial to get closer to the recent theme in T&E community, "Testing at the speed of stakeholder's need and rapid requirement for rapid acquisition."

• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.114-117
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• 2013

The purpose of this study is to empirically investigate accuracy of paper-pencil test used in surveying control-display stereotype. For doing this, three paper-pencil tests dealing with stereotype for control-burner relationship of four-stove gas range, in which three different gas range images were provided, were performed and the results were compared with those of existing studies. The result of the paper-pencil test using simple image composed of line and circle was different from that of the real model simulation, while the results of the other two tests and a previous study providing more realistic images were the same as that of the real model simulation. Furthermore, the proportion of responses coinciding with the real model simulation increased as images used became closer to real range. It is concluded that the paper-pencil tests well designed using realistic images may produce the same stereotype as the real model simulation.

• Journal of the Korean Wood Science and Technology
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• v.47 no.3
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• pp.311-323
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• 2019

The number of newly constructed traditional Korean houses, i.e., Hanoks, and light-frame buildings is increasing. However, related research is limited owing to the lack of awareness regarding safety evaluations. Therefore, this study conducted an outdoor exposure test to accurately evaluate wooden constructions. Spruce, pine, and fir (SPF) material was monitored for a year, wherein the SPF material was artificially dried under 18% moisture content, and its physical properties and color differences were measured once a month. Large differences were observed in the material's weight and moisture content, which are indexes sensitive to daily range and rainfall; however, no significant difference was found for other basic properties in the pre and post test results. Herein, $L^*$, $a^*$, and $b^*$ values represent color differences; these values exhibited a general decrease after the test. Such differences were attributed to the loss of lignin in the wood. The color difference value was high between the months of May and July, when the daily range and rainfall significantly fluctuated. Multiple regression analysis was performed on the $a^*$ value (redness indicator), daily range, rainfall, and ultraviolet index. The results indicated that the daily range influenced redness the most. According to the estimated regression equation, the daily range and redness are positively correlated. Based on the results, the types and influence of independent variables on color difference are expected to change as the wood's duration of outdoor exposure and the amount of data obtained both increase.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.3
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• pp.215-226
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• 1999

The experimented rangefinder consist of sets of V/A-Code GPS and sets of L1 C/A-code & carrier phase receivers connected by two spread spectrum radio modems in order to measure relative range and bearing between two ship antennas by real time, comparing and analyzing accuracy of both GPS receivers at the fix point on the land by means of executing zero baseline test by C/A code and by carrier phase as well as measuring distance range 5m, 10m, 15m between each other receivers. The results from the measurement of relative range and bearing are as follows as ;1. According to the results from zero baseline test, the average error by C/A-code receiver is less than 0.1m, which proves theories from published books but when each GPS receivers track different satellites, the range accuracy error becomes up to 100m by means of S/A. Because of this sudden wide range error, rangefinder is not appropriate at relative range measurement without additional modification of the algorism of the GPS receiver itself.2. According to relative range measurement by Carrier Phase and zero baseline test at static condition, the range error is less than 3.5cm in case that it passes more than 5 minutes after GPS sets can track simultaneously more than 6 satellites. Its main reason is understood that the phase center of antenna is bigger than geodetic antenna.3. When range measurement of two receivers from 5m, to 10m to 15m, the each range error is 0.340m, 0.190m, 0.011m and each standard variation is 0.0973m, 0.0884m, 0.0790m. The range error and standard variation are in inverse proportion to distance between two receivers. 4. L1 Carrier Phase GPS generally needs 5 minutes to fix and during this ambiguity search, the relative range and bearing angle is shown to be various.