• Title/Summary/Keyword: 저압 측정

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A High Efficiency Electronic Ballasts for Low pressure Sodium Lamps (저압나트륨램프용 고효율 전자식안정기)

  • Park, Jae-Kweon;Choi, Hyun-Bae;Yi, Chin-Woo
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.05a
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    • pp.178-180
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    • 2005
  • 본 논문에서는 65 [W] 저압나트륨램프용 전자식 안정기를 제작하여 전기, 광학적 특성을 측정하였다. 개발한 전자식 안정기는 구동주파수가 200 [kHz]로, 기존의 25 [kHz] 전자식 안정기에 비하여 20% 이상의 효율향상을 달성하였다.

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Design and Performance Evaluation of Low Pressure Impactor (저압 임팩터의 설계 및 성능평가)

  • 임경수;권순박;이규원;배귀남
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.11a
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    • pp.119-120
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    • 2000
  • 일반적으로 다단 임팩터는 대기 에어로졸의 입경별 질량농도분포를 측정하는데 많이 사용되고 있다. 임팩터는 입자의 관성을 이용하여 기류로부터 입자를 분리하므로, 0.4 $\mu\textrm{m}$ 이하인 미세 입자의 경우 관성력이 작아 보통의 임팩터로는 입자를 분리하는데 어려움이 있다. 미세 입자에 대한 관심이 높아짐에 따라 저압(low pressure)이나 미세 오리피스(micro-orifice)를 사용하여 미세 입자를 분류할 수 있는 임팩터가 개발되어 사용되고 있다. (중략)

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The Effect of the Plantar Pressure on Dynamic Balance by Fatigue of Leg in the Subjects with Functional Ankle Instability (기능적 발목 불안정성시 하지 근피로에 의한 동적균형이 족저압에 미치는 영향)

  • Kim, Ho-Sung
    • The Journal of the Korea Contents Association
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    • v.16 no.1
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    • pp.734-742
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    • 2016
  • Purpose : The present study was aimed at investigating the plantar pressure on dynamic balance of subjects with functional ankle instability following fatigue of lower leg. Methods : The subjects(30 university students) were divided into 2 groups ; functional ankle instability group(7males and 7females) and ankle stable group(9males & 7females) who could evaluate questionnaire. All the participants were evaluated muscle fatigue of lower leg by Biodex system III and distribution of plantar pressure by Zebris FDM-S system, The dynamic balance was tested by single-leg jump landing. This study were to measure of plantar pressure on dynamic balance with the difference between FAIG and control group following muscle fatigue. Results : In functional ankle instability group(FAIG), the post-fatigue was significantly higher than pre-fatigue in forefoot(p2,p3,p4) of plantar pressure on dynamic balance(p<0.05). The FAIG was significantly higher than the ASG in forefoot(p2, p3, p4) & lat midfoot(p6) of plantar pressure after fatigue in dynamic balance(p<0.05). The FAIG was significantly longer than the ASG in anteroposterior(AP) & mediolateral(ML) distance on center of pressure(CoP) after fatigue in dynamic balance(p<0.05). Conclusion : This study showed that FAIG were effected plantar pressure and center of pressure(CoP) by dynamic balance following muscle fatigue. Further study is needed to measure various age & work with ankle instability for clinical application.

Characteristics of Knee Joint Flexion Angle and Foot Pressure according Slope Climbing (경사로 오르기 동안 슬관절 굴곡각도와 족저압의 특성 비교)

  • Oh, Tae-Young;Song, Hyeon-Ju;Lee, Seul-Gi;Jung, Ye-Ji;Lim, Jong-Su
    • The Journal of the Korea Contents Association
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    • v.10 no.2
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    • pp.268-276
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    • 2010
  • This study was to investigate the knee joint flexion angle and the foot pressure during climbing with different slope. The 24 healthy subjects were participated. And foot pressure was investigated using Parotec system. The knee joint flexion angle were filmed to using a video camera on each slope($0^{\circ},\;3^{\circ},\;6{\circ},\;9^{\circ}$). And knee joint angle was investigated by Dartfish. The data were analyzed ANOVAs. In conclusion, there was significantly different that knee joint flexion angle related on each slope angle. In foot pressure, there was significantly different in lateral heel area(1 cell), medial midfoot area(9 cell), medial forefoot area(15, 16 cell) of left foot, and in lateral heel area(3 cell) of right foot. There was significantly different of foot pressure in lateral and medial heel when knee joint flexion angle is between $10^{\circ}$ and $20^{\circ}$. There was change of gait cycle according to walking slop angle increasing, and the initial contact phase was shorter, the foot pressure in lateral heel was lower.

Investigation and Economic Evaluation of Tunnel Lighting Installation for Each Light Source (광원의 종류에 따른 터널조명 설비의 실태조사 및 경제성 평가)

  • Kim, Gi-Hoon;Lee, Chang-Mo;Sim, Sang-Man;Jeong, Jong-Chul;Kim, Hoon
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2001.11a
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    • pp.93-99
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    • 2001
  • 광원별로 형광등 32W 3등을 사용한 터널과 고압나트륨 램프 100W를 사용한 터널, 그리고 저압나트륨 램프 36W와 91W를 혼용한 터널의 조도 및 휘도를 측정한 결과 조도 및 휘도의 균제도는 3 가지 광원이 모두 거의 일치하였으나, 평균 조도와 정균 휘도값에 있어서 저압나트륨 램프를 사용한 터널이 절반 수준이 되는 차이를 보였다. 또한 경제성 평가 도구인 WEELS를 이용하여 터널의 길이를 300[m], 터널 폭을 10.7[m]로 일정하게 하여 경제성을 평가한 결과, 연간 비용에 있어서 고압나트륨 100W가 비용이 가장 켰고, 그 다음이 형광등 32W 3등용, 그 다음이 저압나트륨(36W+91W)이었지만 그 값은 근소한 차이였다.

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A Study of Change of Air-arc Behavior due to Pressure Waves in Low Voltage Circuit Breakers (저압차단기 기중아크의 압력파에 의한 거동 변화 연구)

  • Song, T.H.;Kwon, J.L.;Kwak, C.H.;Kwon, K.J.
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.1330-1331
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    • 2008
  • MCCB와 같은 저압차단기는 접점사이에서 발생한 아크를 금속의 소호그리드로 유입하여 아크를 소호하게 된다. 일반적으로 고장 전류 차단시에 저압차단기에서 발생한 아크는 고압.고열이므로 아크에너지에 의해 소호부의 압력이 크게 상승하게 되며 압력에 의해 아크의 거동은 큰 영향을 받게 되므로 아크 구동력의 증가를 위해서는 압력에 의해 아크거동이 어떠한 영향을 받는지에 대한 정보가 필요하다. 본 연구에서는 압력파의 영향을 명확하게 하고 다른 요소에 의한 영향을 배제하여 압력파와 아크거동간의 상호작용만을 실험하기 위해 시험용 소호부를 고안하여 시험용 소호부에서 아크의 압력과 거동을 측정.분석하여 아크거동과 압력파의 관계를 연구하였다.

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Comparison of Plantar Foot Pressure and Shift of COP among Level walking, Stairs and Slope Climbing (평지 보행 그리고 계단과 경사로 오르기 동안 압력중심 이동경로 및 족저압 비교)

  • Han, Jin-Tae;Kim, Kyoung;Lim, Seung-Geon
    • Korean Journal of Applied Biomechanics
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    • v.18 no.4
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    • pp.59-65
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    • 2008
  • The purpose of this study was to investigate the shift of COP pathway and the plantar foot pressure among level walking and stairs and ramp climbing in young and elderly people. Plantar foot pressure was measured by MatScan system(Tekscan, USA). Statistical analysis was used One-way ANOVA to know the characteristics of peak plantar pressure during walking with different the facilities. In young adults, COP pathway during stairs climbing was slightly shorten and trended to abduct at forefoot. COP pathway during ramp climbing was also shorten but trend to adduct at forefoot. Peak plantar pressure of 2-3 metatarsal head and heel during ramp climbing was more decreased than level walking. In elderly people, COP pathway during stairs climbing was more shorten and abducted than leve walking and COP pathway during ramp climbing was more unstable than level walking. Peak plantar pressure of first metatarsal head increased at stair climbing and decreased at ramp climbing. That of second metatarsal head and heel was more decreased at ramp climbing. Conclusionally, Peak plantar pressures of each foot region generally increased and more changed during ramp climbing.

A Study on the Evaluation of Uncertainty in Current Measurement for the Short-circuit Test System (단락시험설비의 측정 전류 불확도 추정에 관한 연구)

  • Kim, Dong-Su;Lee, Ki-Taek;Ryu, Jae-Nam;Kim, Chul-Hwan
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1041-1042
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    • 2011
  • 저압 차단기의 단락성능평가를 위한 단락시험설비의 측정시스템은 고전압, 대전류를 안전하고 정밀하게 측정하기 위해 여러 가지 측정기들로 시스템으로 구성되어 있으며, 시험 신뢰도의 확보를 위해 측정불확도에 대한 평가가 이루어져야 한다. 본 논문에서는 표준 Shunt와 비교시험을 통하여 전류 측정 시스템의 측정불확도를 추정하고자 한다.

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Analysis of Plantar Foot Pressure and Pathway of COP Depending on Inclination of Descending Ramp (내림 경사로의 기울기에 따른 족저압과 압력중심이동경로 분석)

  • Han, Jin-Tae;WhangBo, Gak
    • The Journal of the Korea Contents Association
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    • v.10 no.8
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    • pp.257-265
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    • 2010
  • The purpose of this study was to investigate the effect of different ramp inclination on the maximum plantar foot pressure and pathway of the center of pressure. Fifteen healthy adults who had no musculoskeletal disorders were participated with this study and descended the ramp with different inclination(level, $-5^{\circ}$, $-10^{\circ}$, $-15^{\circ}$). Plantar foot pressures were recorded by the Matscan system(Tekscan, Boston, USA) during level and descending ramp with barefoot. Plantar foot surface was defined as seven regions for pressure measurement; two toe regions, three forefoot regions, one midfoot region, one heel region. Repeated ANOVA was used to compare each region data of foot according to different ramp inclination. As descending ramp inclination became increased, the pressure of hallux region was significantly increased at $-15^{\circ}$ inclination and the pressure of 2-3 metatasal head region were significantly decreased at $-5^{\circ}$, $-10^{\circ}$, $-15^{\circ}$ inclination. The pathway of COP had a tendency to be shifted inside in forefoot and prolonged to great toe as the descending ramp inclination increased. The results indicated that plantar foot pressure could be changed at hallux and forefoot regions with $-5^{\circ}$ ramp inclination and these findings demonstrated that ramp inclination could affect the structure and function of foot.

Deposition Mechanism of Tungsten thin Film in LPCVD System (저압 화학 기상 증착에서의 텅스텐 박막 증착 메카니즘)

  • 김성훈;송세안
    • Journal of the Korean Vacuum Society
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    • v.2 no.3
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    • pp.360-367
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    • 1993
  • 텅스텐 박막 증착의 메카니즘을 밝히기 위하여 먼저 SiH4와 WF6의 열분해 반응에 관한 열역학적 결과들과 표면 촉매 반응에 대한 이론적인 결과들을 고찰하였다. 실험적으론 저압 화학기상 증착법을 이용하여 WF6를 SiH4로 환원시켜 텅스텐 박막을 Si(100) 기판위에 증착하였으며 증착반응 중의 기판 표면의 변화를 in-situ로 측정하였다. 증착 메카니즘을 밝히기 위하여 반응기체를 WF6, SiH4, WF6+SiH4, WF6$\longrightarrow$SiH4$\longrightarrow$WF6+SiH4로 달리하여 반응시켰으며 그 때의 박막 특성과 표면 및 단면 형상을 측정하였다. 이론적인 고찰과 실험적인 결과들로부터 텅스텐 박막은 먼저 Si 기판에 의한 WF6의 환원반응으로 인한 증착과 이어서 SiH4에 의한 WF6의 환원으로 증착됨을 밝혔다.

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