• Journal of Advanced Marine Engineering and Technology
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• 제6권2호
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• pp.69-91
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• 1982

The major factors which affect the crankshaft axial vibration are such items as the axial stiffness and mass of crankshaft, the thrust block stiffness, the propeller's entrained water and the exciting and damping forces of engine, propeller and shafting. Among above mentioned items, the axial stiffness and mass of crankshaft, thrust block stiffness and propeller's entrained water were treated in detail in part I, and so in this paper, the rest of above items will be studied. The exciting forces of crankshaft axial vibration are generated mainly from the gas explosion pressure of cylinder, the thrust fluctuation of propeller, and sometimes the torsional vibration of crankshaft induces the crankshaft axial vibration. As for the propeller thrust fluctuation, its harmonic components can be fairly exactly calculated from the experimental results of propeller in the towing tank, but as the calculation process is rather tedious and laborious, the empirical values are ordinarily used. On the other hand, the table of harmonic components of gas pressure has been already published by major slow speed diesel engine makers, but the axial thrust conversion factor of radial force is not unknown yet, and as its estimated value is unreliable, the axial vibration force of gas pressure is uncertain. As the calculation of damping force is very complicated and it includes some uncertain factors, the thoretically estimated amplitudes of axial vibration are much more incorrect in comparison with those of torsional vibrations. Authors have paid special attentions to deriving the theoretical calculation formula of axial conversion factor of radial force and damping force of crankshaft axial vibration and developed a computer program to calculate resonance amplitudes and additional stresses of crankshaft axial vibrations. Also, to check the reliability of the developed computer program, the axial vibrations of three ships' propulsion shaftings were analyzed and their results were compared with those of measured values and makers' results.

• Korean Journal of Acupuncture
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• 제21권2호
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• pp.177-192
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• 2004

Objectives : This study is designed to investigate the pathology, acupuncture and moxibustion therapy applicable of the dementia through literature of oriental medicine. Results : The findings of this study are as follows ; 1. The cause of dementia is internal damage of seven emotions(七情內傷), deficiency of the kidney essence(腎精不足), retention of dampness in the mental(痰迷心竅). 2. The acupuncture meridians used often for dementia are $Tok-maek(GV),\;Chok-t'aeyang\;Pang-gwang-Ky\check{o}ng(BL),\;Chok-yangm\check{o}yng\;Wi-Ky\check{o}ng(ST),\;Su-gwor\check{u}m\;Shimp'o-Ky\check{o}ng(PC),\;Su-so\check{u}m\;Shim-Ky\check{o}ng(HT)$. 3. The spots on the body suiTable for acupuncture used for therapy of the dementia are 98 points and extra points are 6 points, total therapeutic acupunture points are 104 points. And acupunture points are frequently used Shinmun(神門-HT7, 24), Paek'oe(百會-GV20, 19), Chok-samni(足三里-ST36, 18), Sugu(水溝-GV26, 17), P'ungnyung(豊隆-ST40, 16), Taech'u(大椎-GV14, 14), $Sam\check{u}mgyo(三陰交-SP6,\;14)$, Shimsu(心兪-BL15, 14), $Taen\check{u}ng(大陵-PC7,\;11)$, Nogung(勞宮-PC8, 11), Sosang(少商-LU11, 10), Kansa(間使-PC5, 10), Naegwan(內關-PC6, 10). 4. The acupoints used often on moxibustion are Paek'oe(百會-GV20), Chang-gang(長强-GV1), Taech'u(大椎-GV14), Kansa(間使-PC5). Conclusion : It is recommended that further study of many sided investigations in the future.

• 한국자동차공학회논문집
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• 제23권2호
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• pp.161-168
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• 2015

Recently, due to various environmental problems such as global warming, increases of international oil prices, exhaustion of resource, a paradigm of world automobile market is rapidly changing from conventional vehicles using internal combustion engine to eco-friendly vehicles using electric power such as EV, HEV, PHEV and FCEV. Generally, in order to measure fuel consumption and pollutant emissions of cars, chassis dynamometer tests are performed on various driving cycles before actual driving test. There are many driving cycles for performance evaluation of conventional vehicles. However, there is a lack of researches on driving cycle for EV. In this study, the urban driving cycle for performance evaluation of electric vehicles was developed. This study is composed of two parts. In the part 1, the urban driving cycle 'GUDC-EV(Gwacheon-city Urban Driving Cycle for Electric Vehicles)' was developed by using driving data, which were obtained through actual driving experiment, and statistic analysis with chronological table. In this paper part 2, in order to verify the developed driving cycle GUDC-EV, virtual EV platforms were configured and simulations were performed with actual driving data using In addition, simulation results were compared with existing driving cycles such as FTP-72, NEDC and Japan 10-15.

• 한국의류학회지
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• 제28권5호
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• pp.701-712
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• 2004

This study is aimed at the application of the apparel size system to be applied for the Internet shopping mall in Korea. Especially this is focused on the presumption of the body measurement according to the age groups and the figure groups. In this regard, a sizing system is to be developed that could be used to approach consumers more easily and provide more fitness and accuracy in terms of size. The target study was on a group of women nineteen to forty-nine years of age. The 4th National Anthropometry Survey data were used in the examination. The results in the study are as follows ; (1) On the Internet apparel shopping malls in relation with this study, no matter what size in the ready-to-wear enterprises was selected by the consumers who once put their information in the member registration, the most appropriate sizes for them are automatically given and transferred to the order forms of chosen enterprises with aid of internal programs of the internet webpage. In addition, when consumers enter their body sizes in the units that are familiar to them, such as inches or centimeters, the units are automatically programed so that they can be converted for the sake of convenience. ; (2) To extract an estimation equation of body size through Multiple Regression Analysis, the circumferences of chest and hip could be presumed by stature, weight, and waist circumference of which most consumers were well aware. For more accurate regression equations, groupings were made in the three categories of age(19∼29/30∼39/40∼49) and in the three body types(Type N, A and H). Then, the regression equations were established for three sectors, $\circled1$ 'chest circumference not filled up', $\circled2$ 'hip circumference not filled up' and $\circled3$ 'neither filled up for chest nor for hip circumference'. The final results of regression were presented in