• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.585-594
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• 2013

In this study, laboratory experiments and numerical simulations were conducted to test the performance of resonance power buoy system proposed by Kweon et al.(2010). The system is composed of a linear generator and a mooring buoy. The mover of the linear generator mainly has heave motion driven by vertical oscillation of the buoy. In this system, the velocity discrepancy between the mover and the buoy makes electricity. However, ocean wave energy as a natural resource around Korean peninsula is comparatively small and the driving force for producing electricity is not enough for commercialization. Therefore, it is necessary that the buoy motion be amplified by using resonance characteristics. In order to verify the resonance effects on the test power buoy, the experimental investigations were conducted in the large wave flume (length of 110 m, width of 8 m, maximum depth of 6 m) equipped with regular and random plunger wave generator. The resonance draft of test power buoy is designed for the corresponding period of incident wave, 1.96 sec. Regular wave test results show that the heave response amplitude operator(RAO) by a test buoy has the amplification of 5.66 times higher compared to the wave amplitude at the resonance period. Test results of random waves show that the buoy has the largest spectrum area of 20.73 times higher at the point of not the resonance period but the shorter one of 1.85 sec. Therefore this study suggests the resonance power buoy for wave power generation for commercial application in the case of the coastal and oceanic area with smaller wave energy.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1368-1370
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• 1995

Lightning impulse voltage is essential to evaluate the insulation performance of electric power apparatus. Recently international standard(IEC-60) on high voltage measurement techniques are being revised. In the draft of this standard, a new calibration method is introduced and the accuracy of most industrial measuring systems is maintained by means of comparison test against the reference measuring systems. Intercomparison tests of dividers for lightning impulse measurement were carried out by KERI. The shielded resisitive divider with 700kV rating developed by KERI were done comparison test with PTB divider with 300kV rating which have the similar charateristics as that were circulated among the laboratories. This paper reports on the comparison test results with full lightning impulse voltages from 126kV to 240kV. It is demonstrated that KERI are capable of realizing the idea in the revision of the IEC standand, that is, to establish traceability.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.2
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• pp.392-405
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• 2014

SSPA experiences a growing interest in twin skeg ships as one attractive green ship solution. The twin skeg concept is well proven with obvious advantages for the design of ships with full hull forms, restricted draft or highly loaded propellers. SSPA has conducted extensive hull optimizations studies of LNG ships of different size based on an extensive hull data base with over 7,000 models tested, including over 400 twin skeg hull forms. Main hull dimensions and different hull concepts such as twin skeg and single screw were of main interest in the studies. In the present paper, one twin skeg and one single screw 170 K LNG ship were designed for optimally selected main dimension parameters. The twin skeg hull was further optimized and evaluated using SHIPFLOW FRIENDSHIP design package by performing parameter variation in order to modify the shape and positions of the skegs. The finally optimized models were then built and tested in order to confirm the lower power demand of twin skeg designed compaed with the signle screw design. This paper is a full description of one of the design developments of a LNG twin skeg hull, from early dimensional parameter study, through design optimization phase towards the confirmation by model tests.

• Health Policy and Management
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• v.13 no.3
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• pp.35-51
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• 2003

This study purports to develop a quality assessment tool for the process of health promotion programs at public health centers(PHC). The draft of the assessment tool developed by the literature was distributed to 242 staffs who were in charge of the health promotion programs at PHCs for evaluating the feasibility of the tool on September and October 2002. The major results of the study were as follows; The quality assessment tool developed in the study consisted of four domains: strategic planning, program management, monitoring and evaluation, and resources and information. The strategic planning dealt with the function of the planning staff and committees, community data analysis, the feasibility of the program, and the approach methods for attaining the goal of the program. The program management included the items on the qualification and power of the program staff. The monitoring and evaluation included the items on the reporting and communication among program units, and feed back after monitoring. Finally, the resources and information dealt with community networking, clients' response, and consulting activity of the staff. The validity of the tools was tested and partly supported by both formative and criterion-related methods. The assessment tools developed in this study could be used by health promotion workers in the self-evaluation of the program quality. In conclusion, the quality assessment tool developed in the study will be a good safeguard for assuring the quality of the process of health promotion programs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.1
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• pp.33-44
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• 1982

In Order to study for the aeration characteristics which is one of the most important unit processes for the activated sludge process, a pitched blade type aeration model of octagonal shape with a draft tube in it was made as a pilot plant. Oxygen transfer rates, power consumptions and fluid velocities and behaviers were measured and evaluated with the various turbine shapes. And with these results, the dimensionless model analysis using the Buckingham ${\pi}$ theorem was discussed for a proper turbine shape determination.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1895-1897
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• 1996

Lightning impulse voltage is essential to evaluate the insulation performance of electric power apparatus. Recently international standard (IEC-60) on high voltage measurement techniques are being revised. In the draft of this standard, a new calibration method is introduced and the accuracy of most industrial measuring systems is maintained by means of comparison test against the reference measuring systems. Comparison tests of dividers for chopped lightning impulse measurement were rallied out by KERI. The 700kV shielded resisitive divider with and without compensation element were done comparison test with 300kV PTB divider which have the similar charateristics as that were circulated among the laboratories. This paper reports on the calculation results of response charateristics obtained by EMTP and the comparison test results with chopped lightning impulse voltages from 150kV to 250kV. It is demonstrated that KERI are capable of realizing the idea in the revision of the IEC standand, that is, to establish traceability.

• Journal of Arbitration Studies
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• v.12 no.2
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• pp.93-114
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• 2003

The Federal Arbitration Act and the States Arbitration acts of the United States approve that the an arbitration clause should be construed broadly and the Courts interpreted it broadly without being curbed by the written meaning of clause itself. The Courts also divided the interpretation of arbitration clause from the interpretation of other clauses of contract to approve the validity of arbitration clause and further expanded the scope of arbitration. However, the Arbitration Act of Korea does not specify a general principle about how an arbitration clause should be interpreted. The Supreme Court did not have a case yet but the lower courts kept their posture that an arbitration clause should be clear by resulting narrow interpretation and should be written to the extent that it excludes the power of courts from jurisdiction. As a result, there would be cases that arbitration is not permitted although an arbitration clause exists. The parties intending arbitration are frustrated about how to draft an arbitration clause into their agreement. There were the cases that the parties which took the prevailing position attempted to delay dispute resolutions by dragging disputes into litigation even if they agreed to resolve through arbitration, on the basis that an arbitration clause was incomplete. Although the arbitration statutes of the United States cannot apply in Korea, the way of their approaches to the interpretation of arbitration clause can be taken into consideration in view of the globalization of arbitration.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.2
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• pp.456-464
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• 2016

NCS development for construction of marine terminal structure was carried out through following procedures such as analysis on characteristics, analysis on duty, development of the first draft for standards, validation of industry sites, duty competency standards through expert committee, and utilizing package. The results were as follows. Firstly, duty competency was classified as levels from 3 to 7. Educational training institutions were followed by 22 universities, 21 colleges, 16 graduate schools, and 10 high schools. Secondly, developed standards were consisted of duty and competency unit. The name of duty was construction of marine terminal structure and competency units were consisted of 9 items as survey on economic effect, evaluation of conditions on construction environment, plan for construction of structure, construction of transfer, mooring, and power equipment, and construction, startup test, and maintenance of terminal structure. 33 competency unit elements below 9 competency units were developed. Thirdly, utilizing package was developed into 3 areas of life-long career path, training criteria, and guidelines for exam according to national competency standards for in order to develop development of labor's career and perform personal management such as hiring and promotion in industry sites.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.2
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• pp.117-127
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• 2019

Vessel's ice speed performances will be verified in ice sea trial but environmental conditions of ice fields are changeable according to the weather condition of ice trial area. Speed performance has to correct in the no wind, wave and current etc. after sea trial. Especially finding ice fields which is exact the same as owner's ice thickness and strength requirements is not easy. Therefore speed correction according to environment condition has to be done after sea trial measurements. Correction methods for ice thickness, ice strength, wave, wind and ship draft, trim, ice drift etc. are checked in ice sea trial based on literature review such as ISO standard, ITTC recommendation, journal papers and proceedings of conferences. Possibility of application for current and ice drift correction in ice field are discussed and measuring schemes and procedures of correction methods are described in this paper. All of correction schemes are calculated for 'Araon' which is ice breaking research vessel with Arctic and Antarctic ice field test results. Analyzed results shows that Araon is satisfied with her official ice speed performance of 3 knots with 10MW power at 1m ice thickness, 570kPa ice flexural strength.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.5
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• pp.96-102
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• 2019

This study investigated the heat dissipation characteristics of a heat-sensitive LED. More than 80% of the power supply is converted into heat energy, which has a fatal impact on the lifetime of the LED. Therefore, the effective heat dissipation characteristics of a heatsink, such as a 30W floodlight, through forced convection were grasped and the heat transfer characteristics were tested. As a result, it was confirmed that the smaller the number of fins, the more the temperature distribution varies according to the wind velocity. In addition, the larger the number of fins, the smaller the temperature difference according to the wind velocity. Therefore, it was found through this experiment that excellent heat dissipation performance was exhibited as the heat dissipation area and wind velocity increased.