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The Effects of PNF Rhythmic Dance on the Change of Static Balance Ability in Young Adults

  • Park, Byeong-Jin;An, Byeong-Min;Yu, Sook-Kyeong;Lee, Han-Sol;Hwang, Youn-Jung;Kim, Sik-Hyun
    • Journal of International Academy of Physical Therapy Research
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    • v.1 no.2
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    • pp.176-184
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    • 2010
  • This study was to investigate the effects of upper and lower limb composing patterns of PNF(proprioceptive neuromuscular facilitation) on the static balance ability by 20 subjects for 6 weeks. This study was measured left one leg standing and right one leg standing with closed eyes on Good Balance system. These results led us to the conclusion that the mean speed of X, Y direction, COP(center of Pressure) velocity moment showed a statistical decrease when applying post-exercise. The above results from this study indicated that upper and lower limb composing patterns of PNF exercise has improved the static balance ability. As a result, this study showed that upper and lower limb composing patterns exercise improve the ability of balance in young adults. Based on this study, it may be applied to old people.

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A Study on the Period of Optimum Defrost of Auto Defrost Unit by the Forced Fan Evaporator (강제 송풍 증발기에 의한 자동제상장치의 최적제상시기에 관한 연구)

  • 구남열;이윤경;하옥남
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.4
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    • pp.329-335
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    • 2003
  • This study is on a experiment which shows to defrost automatically on the optimum time regardless of defrosting method. The result shows that the more defrost layers increase in fin tubes of evaporation, the less the section of the circulating air reduce. Thickness of the frost formation increases, so a pressure difference of ventilation increase, as a result automatic defrosting system sets the time COP drops suddenly up optimum time. Automatical defrosting system can find out the initial related current of evaporator fan motor and the value of load current in the optimum time. And it sets defrosting time, evaporating temperature, and temperature in refrigerator up system requiring value. Consequence of this experiment is that energy consumption with defrost load gets effect of reduction of eleven percent per 25.4 hours compared with common defrosting.

Effects of performance analysis of a desiccant cooling system with a direct evaporative cooler in the regeneration process (재생 입구 직접증발냉각기 적용이 제습냉방시스템 성능에 미치는 영향)

  • Dash, Ulziiutas;Oh, Myung-Do
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.633-638
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    • 2009
  • In this study the performance analysis and cooling capacity of desiccant cooling system incorporating regenerative cooler and direct evaporative cooler in the regeneration air inlet were investigated on the condition of low regeneration temperature and time rotation 180s and area ratio of regeneration to dehumidification section 0.7. The cooling capacity and COP are evaluated at various effectiveness values of the direct evaporative cooler or the regenerative evaporative cooler. As either of effectiveness of the regenerative and direct evaporative coolers of desiccant cooling system increases, both the cooling capacity and COP increase, but effectiveness value of regenerative cooler gives the opposite effect on the system performance. It is found that effectiveness of regenerative cooler less than 0.7 shows the optimum cooling capacity.

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Simulation of the small Refrigeration Cycle as shape change of the Non-Adiabatic Capillary Tube (비단열 모세관의 형상 변경에 따른 소형 냉동 사이클 성능 해석)

  • Nam, Ki-Won;Yi, Dae-Yong;Park, Sang-Goo;Jeong, Ji-Hawn;Kim, Lyun-Su
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.550-555
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    • 2009
  • The present simulation focuses on the effect of the shape of capillary tube-suction line heat exchangers(SLHX), The results in the three cases of the SLHX types show that both of the location and length of heat exchange section influence the coefficient of performance(COP) and cooling capacity. Simulation shows the COP may be improved by 4.6% and the cooling capacity may be improved by 13.6% in the Lateral type.

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A study for a Performance analysis of Hybrid heat pump Air conditioning system (복합열원형 히트펌프 냉난방 시스템의 성능분석에 관한 연구)

  • Lim, Hyun-Mook;Park, Hee-Moon;Cho, Soo;Sung, Uk-Joo;Park, Jin-Hoon;Park, Tae-Jin
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.1373-1378
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    • 2009
  • This study is aiming comparison and analization between efficiency of hybride air conditioning system which uses low temperature water under dam and air and EHP(Electric Heat Pump). The experimental was carried out with air cooling tests for EHP system having 80HP and composition heat pump system. P-i diagram of both systems and COP was used to derive schemetic and calcuations. As results of the tests, hybride system has 1.4 time higher efficiency coefficient.

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Performance Characteristics on Environment Change of A/C applied Fin-tube and PF Heat Exchangers (환경변화에 따른 핀-관, PF 열교환기 적용 공조기 성능 특성 실험 연구)

  • Park, K.M.;Um, U.S.;Kwon, Y.C.;Lee, S.J.
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.1267-1271
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    • 2009
  • In the present study, performance characteristics on environment change of A/C applied fin-tube and PF heat exchangers were experimentally investigated. Capacity and COP changing an outlet air velocity, an indoor/outdoor temperature and a relative humidity were obtained. Air-enthalpy calorimeter was used. As the air velocity, indoor temperature and relative humidity increase, capacity and COP increase. PF A/C has smaller refrigerant weight than the fin-tube A/C. The performance of PF-2 A/C with the squarer fin was more excellent than that of PF-1 A/C with the triangler fin.

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Study on the Performance Characteristics of Hybrid Solar Heating System during Spring Season (봄철 태양열 하이브리드 시스템의 성능특성 연구)

  • Pyo, Jong-Hyun;Kim, Won-Seok;Cho, Hong-Hyun;Park, Cha-Sik
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.22 no.5
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    • pp.296-303
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    • 2010
  • An experimental study was carried out to investigate performance characteristics of the hybrid solar system during spring season. The system operating condition, each load, and heat pump performance were analyzed with the cloud cover. As a results, the collector heat, solar fraction, and hot water load were decreased with a rise of the cloud. The heating load was considerably effected by the ambient temperature regardless of the cloud cover. Besides, the temperature of hot water increased with the solar radiation. The COP of the heat pump was significantly influenced by the ambient temperature, that was 2.09~2.46 for gray day and 1.94~2.71 for fair day, respectively.

The Effect of Static Balance Recovery by Open Kinetic Chain and Closed Kinetic Chain Exercises (열린 사슬 운동과 닫힌 사슬 운동이 정적균형 능력에 미치는 영향)

  • Kwon, Yoo-Jung;Bae, Sung-Soo;Park, Soo-Jin
    • Journal of the Korean Society of Physical Medicine
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    • v.4 no.1
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    • pp.23-30
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    • 2009
  • Purpose : This study was investigated the effect of static balance recovery during open kinetic chain exercise (OKC) and closed kinetic chain exercise(CKC). Methods : The paticipants were consisted of forty-one, was perform 3 sets, 3 times per week for 6 weeks, balance was measured by GOOD BALANCE. Statistical analysis was used repeated measure two-way ANOVA and independent t-test. Results : In CKC group, Center of presure(COP) medial-lateral(ML) velocity was significantly increased post 6 week test than pre-test, post 2 week test. COP anterior-posterior(AP) velocity was significantly increased post 6 week test than pre-test (p<.05). Conclusion : It was found that both OKC and CKC was significantly increased balance recovery in normal younng adults. In further study, it was suggested that was regard patient with muscle weakness.

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Drying Performance Simulation for the Basic Design of a Heat Pump Dryer (열펌프 건조기의 기본 설계를 위한 건조 성능 해석)

  • Lee, Kong-Roon;Kim, Ook-Joong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.31 no.10
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    • pp.860-867
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    • 2007
  • Heat pump drying has a great potential for energy saving due to its high energy efficiency in comparison with conventional air drying. In the present study, the performance simulation for the basic design of a heat pump dryer has been carried out. The simulation includes one-stage heat pump cycle, simple drying process using the drying efficiency. As an example, the heat pump cycle with Refrigerant 134a has been investigated. For the operating conditions such as the average temperature of the condenser, the heat rate released in the condenser, the flow rate of drying air, and drying efficiency, the simulation has been carried out to figure out the performance of the dryer. The parameters considered in the design of the dryer are COP, MER, SMER, the rate of dehumidification, the temperature and humidity of drying air and those parameters are compared for different conditions after carrying out the simulation.

Experimental Study on the Performance Characteristics of an Injection Type Scroll Compressor (인젝션용 스크롤 압축기의 성능특성에 관한 실험적 연구)

  • Cho, Hong-Hyun;Kim, Yong-Chan
    • Proceedings of the KSME Conference
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    • 2000.04b
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    • pp.193-198
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    • 2000
  • For an inverter-driven compressor, the discharge temperature increased with a rise of frequency, Therefore, it is necessary to control the discharge temperature at high frequencies in order to obtain system reliability and efficiency. This paper describes the effects of liquid injection system on the performance of an inverter-driven scroll compressor. Experiments were performed at ASHRAE-T conditions. Frequency was altered from 45 to 105Hz. As results of the present work, the refrigerant discharge temperature fur the injection system was dropped approximately $10{\sim}20^{\circ}C$ as compared to those for the non-injection system. The COP of the compressor was improved approximately $0.8{\sim}9.3%$ at high frequencies(75, 90, and 105 Hz).

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