• Bulletin of the Society of Naval Architects of Korea
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• v.13 no.3
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• pp.21-23
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• 1976

In this paper author has investigated numerically on some properties of Maruo's line integral term associated with the wave resistance theory. The role of Maruo's line integral term for the improvement of Michell's wave resistance calculations are discussed.

• Tribology and Lubricants
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• v.22 no.2
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• pp.73-78
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• 2006

The surface modification of automobile parts is of great technological importance for the improvement of corrosion resistance, wear resistance, fatigue strength and so on. Recently, research on the development of the technology of surface modification substituting 6-balance chrome process has progressively been achieved in automobile parts. Although the innovation technology for the improvement of the corrosion-resisting and wear resistant properties through post oxidation after nitrocarburising process had attracted a great attention. For this, anodically potentiodynamic polarisation testing was carried out to corrosion resistance and friction and wear experiment according to applied load and sliding distance was carried out to evaluate the wear resistance of machine structural steel with nitrocarburising and non-nitrocarburising SM45C. The presumed wear volume was calculated with the image processing far evaluation of wear resistance of two materials. The results show that the nitrocarburising had a distinguished corrosion resistance and wear resistance than non-nitrocarburising.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.3
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• pp.222-226
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• 2005

A series of model tests carried out at the CWC of WJFEL for the purpose of prediction of resistance for the performance and improvement of resistance by attaching appendage for the ship of 50 knots class planing hull. The resistance performance evaluation has been carried out for the bare hull and for the appendage hull with two different depth of vertical type wedges. In the bare model test, trim and sinkage is calculated for the planing hull and the resistance is calculated. For minimizing the resistance, wedge appendage is attached and tested. Analysis and tests shows that for a 12.5mm wedge, resistance is minimum and overall power tallied to 5636ps.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.3
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• pp.294-303
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• 1999

Resistance spot welding is commonly used for welding products of high quality because of clean welding and short w welding-time. But. conventional spot welders bring about the depreciation of welding products, iuespective of dynamic r resistance characteristics during welding time. This paper discussed dynamic resistance database implementation in t terms of welding performance improvement. On different welding conditions, we compared dynamic resistance, r respectively, about pure iron and Sn-Pb alloy on Copper. Also, it investigated the relation of tensile shear strength and d dynamic resistance in welded workpiece.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.1
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• pp.17-22
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• 2004

This study was carried out at the CWC of Chosun university for the purpose of resistance performance improvement of planing hull, and the results of the tests were confirmed cooperatively with WJFEL. G/T 100 ton class planing hull form was selected, and the improvement of hull form including appendages were performed by using some model test techniques. The model test scope comprises resistance relative tests including wave profile observation, trim and sinkage measurement and flow visualization tests at full load and trial conditions for one bare hull and for two appended hulls. The final wedge and spray strip combined with improved hull form showed about 1.0 knot speed improvement at both of full and trial conditions, and outstanding improvement for fore wave phenomena.

• Journal of International Academy of Physical Therapy Research
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• v.2 no.2
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• pp.329-338
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• 2011

The purpose of this study is to examine the effect of stabilization, resistance exercise, and combined exercise for lumbar on balance and walking ability of elderly. This study selected 22 subjects of over 65 years old elderly women who satisfy the study condition from A, B and C Senior Citizen's Center, in Daegu. The subjects were divided into groups; 7 for resistance exercise group, 8 for stabilization exercise group, and 7 for combined exercise group(resistance and stabilization exercise). The exercises were conducted for 60min a day, three times a week for 12 weeks. Balance and walking ability were checked before the exercise, 6 weeks later, and 12 weeks later. First, all lumbar muscle strengthening exercises were effective for static balance which changed according to exercising period. In dynamic balance, the resistance exercise group showed significant improvement in sit to stand. Stabilization exercise group showed significant improvement in all factors. The combined exercise group showed significant improvement in sit to stand and timed up and go. There was no difference between the exercise types. Second, the resistance exercise group showed significant change in Cadence which changed according to exercising period. The combined exercise group showed significant improvement in all factors. Between the exercise types, combined exercise was a bit more effective than resistance exercise. According to the result of 12 weeks of lumbar muscle exercise, combined exercise is considered to be the most effective exercise to prevent fall as it helps balance and walking ability slightly more than other exercises. Therefore, this study can understand the risk factors for fall accidents that frequently occur among elderly and adopt the combined exercise to prevent fall which in turn will prevent secondary problems occur from fall accidents and improve quality of life of elderly.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.6
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• pp.757-762
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• 2010

Korean fishing boats have had appropriate hull forms for the safety, stability and convenience of fishing ability. However, Korean fishermen are recently concerned about the resistance performance and speed of Korean fishing boats, because the prices of fuel oil are gradually risen, also the exhausting of fish resources and the demand of high speed fishing boats are increased. Therefore, the necessity of the study on the improvement of resistance performance for Korean small coastal fishing boats is gradually increased. This study compares the hull form characteristics of Korean fishing boats with those of Japanese fishing boats, and the hull form of a representative Korean fishing boat is modified. From the modification of the hull form parameters for the Korean fishing boat, the improvement of resistance performances is evaluated. Moreover, the increase of resistance performances is also achieved from the modification of local characteristics for the hull form of the Korean fishing boat. A computational method and ship model tests in towing tank are used for the conformations of the improvement of resistance performance.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.416-418
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• 2008

Dye-sensitized solar cell using transparent conducting oxide as electrode has large resistance such as surface resistance, charge transportation impedance in counter electrode and electrolyte, impedance between each interface. Among that resistances, surface resistance of transparent conducting oxide is relatively large. So the change of transparency has a large effect on internal resistance of dye-sensitized solar cell. Consequently, that change cause to increase or decrease the conversion efficiency. We tried to reduce the surface resistance by laser-scribing. The active area is seperated from total transparent conducting oxide by Nd:YAG laser-scribing. As a result, we achieved the improvement of efficiency about 7% and 11% in case of $0.25cm^2$ and $1.00cm^2$ dye-sensitized solar cells.

• Journal of Ginseng Research
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• v.34 no.3
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• pp.155-159
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• 2010

In the present review, the merit of ginseng in the improvement of insulin resistance has been introduced. Using the results in previous studies, we found that ginseng or ginsenoside Rh2 has the ability to reduce glucose-insulin index in rats with insulin resistance. Insulin resistance was induced by feeding of fructose-rich chow in rats. Insulin resistance was characterized by regular methods. Effectiveness of ginseng powder or extract Rh2 was identified in this animal model. Also, the application of ginseng for handling of diabetic disorders in China has been discussed. According to Chinese traditional medicine, ginseng is merit in the treatment of diabetic disorders named as Shiaw-Ker in Chinese. Therefore, it is no doubt that ginseng is helpful in the control of diabetic disorders either prevention or the treatment. Otherwise, the potential effect of ginseng on nervous functions shall be investigated in the future.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.5
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• pp.92-97
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• 2011

This paper deals with the improvement of electrode installation for measurement of ground resistance through investigation on the spot in buildings. The investigation was carried out for an earthing terminal board for measurement of ground resistance, installation of auxiliary electrode, etc. The criteria value is set up by measuring method of ground resistance in international standard. In case of inadequate installation of auxiliary electrode, a relative error is analyzed and adequate installation method of auxiliary electrode is proposed. As a consequence, it is necessary to write direction of ground and equipment, and separate auxiliary electrode for measurement of ground resistance in order to minimize measuring error.