• Journal of Sport and Applied Science
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• v.7 no.2
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• pp.1-12
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• 2023

Purpose: The purpose of this study was to investigate the possibility of modified swing to prevent shoulder injury by analyzing differences in the muscle activation patterns of upper limb by the swing method in wheelchair badminton players. Research design, data, and methodology: 10 wheelchair badminton players participated in the experiment as subjects and performed 10 high clears and 10 smashes in both traditional and modified swing methods toward a shuttlecock hung at the height of racket impact point. For each trial, activation patterns of biceps brachii, triceps brachii, anterior deltoid, and posterior deltoid were measured from the upper limb participating in the swing from which the duration, peak, and root mean square (RMS) of electromyography (EMG) activities from swing initiation to shuttle impact were calculated. The maximum swing velocity of the smash and the distance of the high clear were also measured with both methods to compare differences in the swing velocity and shuttle hit distance. Results: Differences in the EMG peak and RMS of the anterior deltoid by swing methods were shown to differ by the skill type, being higher in the traditional swing method than the modified during only the high clear. The EMG peak and RMS, and the duration of the posterior deltoid were higher and longer with the traditional swing method than the modified during both the smash and high clear. The intensities of the biceps brachii and triceps brachii activities measured during the smash and high clear were higher in the traditional swing method than the modified, and the biceps brachii and triceps activity durations during the high clear were shorter in the modified swing method than the traditional. The maximum swing velocity of the smash was faster with the traditional swing method than the modified, while the distance of the high clear did not differ significantly. Conclusions: These results suggest that the modified swing can be an effective performance method for preventing shoulder injuries without undue loss of impact power in wheelchair badminton players by reducing excessive loads imposed on the shoulder and allowing the optimal use of the elbow extension.

• The Korean Journal of Air & Space Law and Policy
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• no.spc
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• pp.137-163
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• 2007

The air market in Asia has already entered upon the age of limitless competition. It means a very important moment in Asia air market. Each Asian country thus has put a lot of effort into a development plan and support to their hub airport. In order to achieve such a plan, first of all we should build closer cooperation system between the two countries Japan and Korea. The Korea and Japan are very fast growing in the northeast countries within the global air transport market. Air passenger and cargo traffic volumes between Korea and Japan have increased dramatically, since the 1990s. In response to such a trend, both countries have opened new airports and expanded existing facilities in the hopes of laying claims to the main international hub airport in Asia. Apart from the trend, air transportation between Korea and Japan's metropolitan areas is the only transportation in substance, even if they are located very closely in geographical position. The air transportation between the two countries shows that it is necessary to get fast and more convenient because of the economic and cultural interchange and exchange concentrated on the metropolitan areas, and that will promote the economic growth of Korea and Japan. However, within the air transportation industry field, there have no sufficient seats/slots to supply the air demand from the capital cities of each country, as well as no counterplan for some problems regarding capacityand sustain ability of metropolitan airports. Thus, it is necessary for us to consider in all aspects and solve them to improve air transportation between Korea and Japan. This paper is to try to demonstrate this matter and from all angles, that is, in legal and political aspects, facilities and given environmental conditions and cooperation between Korea and Japan. I think that it is indeed a great necessary and convenient for many Korean and Japanese tourists to conclude a new 'Open Sky Agreement' between Japan and Korea in order to the prepare the increase of the shuttle flight between Haneda-Gimpo and opening of air route newly for shuttle flight between Haneda and Cheongju as well as opening of air route for shuttle flight between Haneda-Shanghai Hongqiao International Airport and Beijing International Airport for the 2008 Beijing Olympic Games. Furthermore it is a great desirable thing for us to conclude a new 'Open Sky Agreement' in cooperation reciprocally among the Japan, China and Korea for opening the new air route by the shuttle flight.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.92-98
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• 1988

The present study was performed to find the effects of ginseng and its saponins. which is written in Chung Yao Ta Tsu Tien as anti-amnesia in its chief indication. on experimental amnesia in mice. In the step through test. ginsenoside $Rb_1\;(GRb_1)\;and\;GRg_1$ facilitated the registration of memory and antagonized the electroconvulsive shock (ECS)-induced inhibition of the retention of memory. Moreover. $GRg_1$ antagonized the EtOH-induced inhibition of the retrieval of memory. In the step down test. $GRb_1\;GRb_2\;and\;GRg_1$ antagonized the ECS-induced inhibition of the retention of memory. Moreover. $GRg_1$ antagonized the EtOH-induced inhibition of the retrieval of memory and facilitated the acquisition of short term memory. In the shuttle hox and lever press tests. they have no effects on acquisition and retrieval of memory. except $GRb_1\;GRb_1$ depressed the retrieval of conditioned avoidance response in the shuttle box test. After the end of four tests. the effects of these orally administered drugs on sedative. analgesic. antipyretic and anticonvulsant actions. and on spontaneous and exploratory movements were tested in doses of less than 500mg/kg. but they had none of these effects. Present study may indicate that $GRg_1$ had effects on the retrieval of memory and on the acquisition process of learning response. The recent research on the role of NGF for the survival. regeneration and regulation of brain in adult animals. indicated the importance of NGF on dementia and amnesia. During our research on the specificity of the neurite out growth induced by NGF. we found that the effect of NGF was potentiated by $GRb_1$ in organ cultures of chick embryonic dorsal root ganglia. Then. the effect of $GRb_1$ on neuronal cell survivalin cell culture system was studied. $GRb_1$ potentiated the NGF-mediated increase of neurofilaments in cell cultures of chick embryonic sensory and sympathetic neurons. NGF with $GRb_1$ also showed a tendency to increase the number of surviving neurons of rat embryonic cerebral cortex. NGF increased choline acetyl transferase activity in cell cultures of rat embryonic septum area neurons. but $GRb_1$ did not potentiate NGF activity in cell cultures of rat embryonic septum area neurons. Present study may indicate that $GRb_1$ plays an important role for the survival or regeneration of neurons in the brain.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2044-2049
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• 2007

In order to predict the thermal radiation induced from alumina particle cloud in the plume of solid propellant motor, view factor method is applied to space shuttle SRB and the result is compared with that of monte carlo method. For this purpose, radiative characteristics, such as particle cloud temperature distribution, effective emissivity or emissive power of particle cloud are studied. In the case of effective emissivity, inverse wavelength method is applied and plume reduction characteristic length is used for emissive power distribution. As a result, thermal radiation using view factor method gives more conservative results than that using monte carlo method. So it can be used for preliminary design of thermal protection system.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.504-513
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• 1997

Ideal candidates for the thermal-protection system of advanced spacecraft like Space Shuttle, are FRCI(Fibrous Refractory Composite Insulation) and AETB(Alumina-Enhanced Thermal Barrier). In the present work, we carried out the mathematical modeling and computer simulation of the thermal response of FRCI to heat, pulse, comparing with that of silica. Also, we calculated the conductivity of FRCI as various variables at the temperature range of 100~2000 K.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.4-12
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• 1996

This keynote presentation covers the subject of intelligent systems development for monitoring and control in various NASA space applications. Similar intelligent systems technology also has applications in terrestrial commercial applications. Discussion will be given of the general approach of intelligent systems and description given of intelligent systems under prototype development for possible use in Space Shuttle Upgrade, in the Experimental Crew Return. Vehicle, and in free-flying space robotic cameras to provide autonomy to these spacecraft with flexible human intervention, if desired or needed. Development of intelligent system monitoring and control for regenerative life support subsystems such as NASA's human rated Bio-PLEX test facility is also described. A video showing two recent world's firsts in real-time vision-guided robotic arm and hand grasping of tumbling and translating complex shaped objects in micro-gravity will also be shown.

• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.1-8
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• 2009

This is a short review of how CFD contributed to hypersonic flights in the past 50 years. Two unexpected phenomena that occurred in the entry flights of the Apollo and Space Shuttle made us aware of the impact of the high temperature real-gas effects on hypersonic flights: pitching moment anomaly of up to 4 degrees, and radiation overshoot behind a shock wave. The so-called two-temperature nonequilibrium model was introduced to explain these phenomena. CFD techniques were developed to accommodate the two-temperature model. Presently, CFD can predict trim angle of attack to an accuracy of about 1 degree. A concerted effort was made to numerically reproduce the experimentally measured flow-field over a double-cone. As yet, perfect agreement between the experimental data and computation is not achieved. Scramjet technology development is disappointingly slow. The phenomenon of ablation during planetary entries is not yet predicted satisfactorily. In the future, one expects to see more research carried out on planetary entries and space tourism.

• KSBB Journal
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• v.6 no.3
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• pp.223-230
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• 1991

Using the shuttle vector pECCGl between Escherichia coli and Corynebacterium glutamicum and C. glutamicum strain JS231 grown in the medium supplemented with penicillin-G, which inhibits the formation of cross-links in the peptidoglycan of bacterial cell wall, various parameters involved in electroporation system including resistance, electric field strength, capacitance, DNA concentration, and cell density were investigated independently and optimized for the high efficiency transformation of coryneform bacteria. Using cells grown with 0.3U/ml of penicillin-G and harvested at A600 of 0.7-0.8, transformation efficiencies of 107-l08 transformants/$\mu\textrm{g}$ of DNA with Corynebcctertum glutamicum strain JS231 and wild type ATCC13032 were achieved under conditions of 12.5kV/cm of electric field strength, 400 ohms of resistance, $25\mu$F of capacitance, 3$\times$108 cells per transformation(1.2$\times$1010 cells/ml) and 100ng of plasmid DNA per transformation.

• International Journal of Fluid Machinery and Systems
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• v.10 no.2
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• pp.99-118
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• 2017

ECHO progress was defined to depict the rotordynamic pump theory development. Experience (E) era for pumps lasted nearly one and a half hundred years before the Industrial Revolution due to the low rotation speed of motor and undeveloped manufacture ability. Classic (C) theory referring to quasi-static performance as well as the items those were not able to be steadily resolved under the level were briefly and sophisticated outlined. Since 1962, flow instabilities and the dynamic responses had come into main attention with the development of the modern technologies such as ballistic missile, rocket and space shuttle main engine, and were finally heuristically (H) elucidated by talented scholars and researchers. Recently, new applications for the pumps open (O) to the surrounding fluid and diversity of the medium such as multiphase flow need more studies and some examples were briefly introduced to display the potential problems lastly.

• BMB Reports
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• v.35 no.5
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• pp.443-451
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• 2002

Malonate is a three-carbon dicarboxylic acid. It is well known as a competitive inhibitor of succinate dehydrogenase. It occurs naturally in biological systems, such as legumes and developing rat brains, which indicates that it may play an important role in symbiotic nitrogen metabolism and brain development. Recently, enzymes that are related to malonate metabolism were discovered and characterized. The genes that encode the enzymes were isolated, and the regulation of their expression was also studied. The mutant bacteria, in which the malonate-metabolizing gene was deleted, lost its primary function, symbiosis, between Rhizobium leguminosarium bv trifolii and clover. This suggests that malonate metabolism is essential in symbiotic nitrogen metabolism, at least in clover nodules. In addition to these, the genes matB and matC have been successfully used for generation of the industrial strain of Streptomyces for the production of antibiotics.