• 제목/요약/키워드: volume effects

검색결과 4,213건 처리시간 0.035초

공압 전달관의 동적 응답 (Dynamic Response of Pneumatic Transmission Lines)

  • 박현우;박종호;신필권;심우건
    • 소음진동
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    • 제9권2호
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    • pp.285-294
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    • 1999
  • Transient analysis for compressible fluid flow has been performed experimentally and analytically to study the dynamic characteristics of the end volume transmission lines following a sudden pressure change a its entrance. The numerical method was developed based on the method of characteristics. The sudden pressure at its entrance was generated by rupture of diaphragm in a shock tube. The sudden pressure was used to obtain the response, as input signal for the numerical analysis. The response to the sudden pressure at the end volume was measured using a pressure transducer. The experimental result shows good agreements with the numerical result. The effects of tube length, its diameter and end volume magnitude are evaluated on the responses of the pressure and on the damping factor. It is found that the viscous damping effects on the response through the transmission pipeline becomes larger with increasing pi;eline length and decreasing diameter of the pipe and the fluid-elastic stiffness decreases with increasing the terminal volume. The numerical approach presented in this paper can be very useful in designing the instrument and control system.

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간섭 전류 자극이 상지 혈류변화에 미치는 영향 (The Effects of Interferential Current Therapy on Blood Flow in upper limbs)

  • 박래준;박영한
    • The Journal of Korean Physical Therapy
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    • 제15권4호
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    • pp.140-150
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    • 2003
  • The purpose of study was to compare change of blood volume on upper limb of stimulus site on interferential current therapy. Twenty university student(twelve females. eight males :mean aged 23.08) with health condition participated this study MP150 system(biopac system) was used to measured blood volume. PPG senser was located thrum finger end The obtain result are as follows. 1. The result of this study were following that stimulate time blood volume were significantly increased sympathetic stimulation group compared with muscle stimulation group(p<.05). 2. The result of this study were following that stimulate time blood volume were significantly increased sympathetic stimulation group compared with muscle stimulation group(p<.05). 3. The result of this study were following that sympathetic stimulation group were significantly increased stimulate time blood volume compared with stimulate time blood volume(p<.05). 4. The result of this study were following that muscle stimulation group were significantly increased stimulate time blood volume compared with stimulate time blood volume(p<.05).

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오약순기산가미방의 항염작용과 Collagen 유발 관절염의 발생억제 및 치료효과 (Anti-inflammation, Anti-Development and Curative Effects of Oyaksunki sangamibang on the Collagen-Induced Arthritis in Rats)

  • 이찬범;오민석
    • 대한한의학회지
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    • 제26권3호
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    • pp.176-187
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    • 2005
  • Objectives : This study was carried out to investigate the anti-inflammation, anti-development and curative effects of Oyaksunki-sangamibang (OSKM) on collagen-induced arthritis in Wistar rats and ICR mice. Materials & Methods : D experiment part II, the inhibitory effects of nitric oxide synthesis, pro-inflammatory cytokines, and cyclooxygenase were studied. In experiment part II, paw eduma volume and thickness of ankle joint were measured at 0, 10, 15, and 20 days after immunization. The incidence and arthritis score were evaluated 14 days after immunization, At 15 days after immunization, serum $TNF-\alpha$ was analyzed. In experiment part III paw edema volume and thickness of ankle joint were measured at 0, 10, and 15days after treatment. At 15 days after treatment, serum $TNF-\alpha$ was analyzed. Results : In experiment part I: 1. Nitric oxide synthesis ·md pro-inflammatory cytokines were inhibited significantly by OSKM extract. 2. Cyclooxygenase 2 (COX-2) was inhibited by OSKM extract. In experiment part II: Paw edema volume, thickness of ankle joint and serum $TNF-\alpha$ level of the teated group were significantly decreased compared with the control group at 20 days after immunization. In experiment part III: Incidence of arthritis was $70\%$. OSKM-treated group had no significant change on paw edema volume, thickness of ankle joint and serum $TNF-\alpha$ level. Conclusions : These results indicated that OSKM has anti-inflammation effects on the ICR mouse, and higher inhibitory effects on the onset but lower inhibitory effects on the progression of collagen-induced arthritis in rats.

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수량 및 제품유연성이 의료조직의 성과에 미치는 영향 (Effects of Volume and Product Flexibilities on Hospital's Performance)

  • 박보영;손병규
    • 한국콘텐츠학회논문지
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    • 제11권3호
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    • pp.389-402
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    • 2011
  • 의료조직 경영에 대한 기존의 연구들은 의료서비스의 품질 혹은 운영의 효율성을 위한 연구에 집중된 반면에 본 연구는 조직운영의 중요한 전략적 요소인 유연성이 의료조직의 경영에 어떠한 영향이 있는지를 연구하였다. 특히 의료조직의 수량유연성과 제품유연성을 대상으로 이들 유연성의 원천이 되는 내부 및 외부 자원의 활용이 조직의 재무적 성과에 미치는 영향을 분석하였다. 국내 병원들을 대상으로 표본을 추출하였고, 설계된 설문지를 이용하여 연구변수들의 측정 자료를 수집하였다. 연구변수들의 관계를 가정한 가설을 검정하기 위하여 회귀모형을 수립하고 분석한 결과 내부자원에 기반한 수량유연성이 성과에 직접적으로 영향을 줄 뿐 아니라 제품유연성의 내부자원 및 외부자원의 활용과 상호작용을 통해서도 성과에 영향을 주는 것으로 나타났다. 반면에 외부자원에 의한 수량유연성은 조직성과에 유의적인 영향이 없는 것으로 나타났다. 이들 분석결과에 대한 설명과 관리적 시사점을 논의하였다.

텅스텐 중합금의 단열전단밴드 형성 연구 (A study on the Formation of Adiabatic Shear Band of Tungsten Heavy Alloys)

  • 이승우;문갑태;홍성인
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2002년도 춘계학술대회 논문집
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    • pp.187-190
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    • 2002
  • To study adiabatic shear band formation of tungsten heavy alloys, 5 prismatic specimens are loaded by high velocity impacts and treated as plane strain problems. Their volume percent of tungsten particles in WHA are 81%, 93% and 97% respectively and for the fixed 81% volume percent, small size particle model, large size particle model, undulated particle models are considered and then, the effects of particle's volume ratio, geometry and size to the formation of shear band are discussed.

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제지 원료의 특성 및 물리적 처리가 종이의 기공 구조 및 물성에 미치는 영향 (Effects of Raw Materials for Papermaking and Physical Treatment on the Pore Structure and Paper Properties)

  • 원종명;남기영;정순기
    • 펄프종이기술
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    • 제39권4호
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    • pp.7-13
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    • 2007
  • Effects of pulp type, refining and filler type on the pore characteristics and physical properties of paper were investigated. HwBKP, SwBKP and BCTMP are used to study the effect of pulp type in this study. The effects of each filler (PCC, GCC and talc) and the combination of PCC/GCC were also studied. Highest bulk, pore volume and light scattering are obtained from BCTMP and PCC. It was found that the pore size and pore volume are important in light scattering in paper structure. It was found that PCC was the most effective filler for the improvement of the bulk and light scattering because of the increase in pore volume which can scatter light, but the increase of PCC content was not so effective in the improvement of bulk.

Sweet Bee Venom 시술이 Rat의 호흡기계에 미치는 영향 (Effects of Sweet Bee Venom on the respiratory system in Rats)

  • 이종영;권기록
    • 대한약침학회지
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    • 제14권3호
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    • pp.47-53
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    • 2011
  • Objectives: This study was performed to analyse the effects of Sweet Bee Venom(SBV-purified melittin supported by G&V Co., the major component of honey bee venom) on the respiratory system in rats. Methods: All experiments were conducted at Biotoxtech Company, a non-clinical studies authorized institution, under the regulations of Good Laboratory Practice(GLP). Male rats of 5 weeks old were chosen for this study and after confirming condition of rats was stable, SBV was administered in thigh muscle of rats in 0.175, 0.35 and 0.7 mg/kg dosage. And checked the effects of SBV on the respiratory system using the whole body plethysmography. And respiratory rate, tidal volume and minute volume of rats were checked after administered SBV (melittin). Results: 1. In the measurement of respiratory rate, there were not observed any significant differences compared with control group. 2. In the measurement of tidal volume, there was not observed any significant differences compared with control group. 3. In the measurement of minute volume, 0.35mg/kg dosage group showed significant differences compared with control group. But we estimated that this result was caused by individual differences. Conclusions: Above findings suggest that SBV seems to be safe treatment in the respiratory system of rats. And further studies on the subject should be conducted to yield more concrete evidences.

음식물쓰레기의 호기성 퇴비화에 있어서 왕겨와 톱밥의 영향에 관한 비교 연구 (Comparison of Effects of Chaff and Sawdust on Aerobic Composting of Food Wastes)

  • 박석환
    • 한국환경보건학회지
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    • 제29권3호
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    • pp.28-34
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    • 2003
  • This study was performed to compare the effects of chaff and sawdust as bulking materials on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor of Control, Ch-l, Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Volume ratios of food wastes to sawdust in reactor of Control, Sd-l, Sd-2, Sd-3 and Sd-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wastes to chaff and sawdust resulted in the reaction at higher reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff and sawdust resulted in faster pH increase. In the volume ratio of 4:3 and 4:4, pH increased faster in food-chaff mixtures than in food-sawdust mixtures. The lowering of the volume ratio of food wastes to chaff and sawdust resulted in faster steady state in the weight reduction rate and the volume reduction rate. The weight reduction rates of chaff mixtures were higher than those of sawdust mixtures, but the volume reduction rates of sawdust mixtures were more higher than those of chaff mixtures. Salinity increased as composting reaction proceeded, due to reduction in mass weight. The final salinity of Control was 2.79%, and the final range of salinities of chaff and sawdust mixtures were 2.18∼2.37% and 1.86∼2.05%, respectively.

Effects of vasopressin administration in the oral cavity on cardiac function and hemodynamics in rats

  • Fukami, Hayato;Sunada, Katsuhisa
    • Journal of Dental Anesthesia and Pain Medicine
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    • 제22권1호
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    • pp.11-18
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    • 2022
  • Background: The vasoconstrictive effect of epinephrine in local anesthetics affects the heart, which leads to hesitation among dentists in injecting local anesthetics into patients with cardiovascular disease. Due to its vasoconstrictive effects, the present study investigated the effects of vasopressin administration on cardiac function in rats. Methods: Experiment 1 aimed to determine the vasopressin concentration that could affect cardiac function. An arterial catheter was inserted into the male Wistar rats. Next, 0.03, 0.3, and 3.0 U/mL arginine vasopressin (AVP) (0.03V, 0.3V, and 3.0V) was injected into the tongue, and the blood pressure was measured. The control group received normal saline only. In Experiment 2, following anesthesia infiltration, a pressure-volume catheter was placed in the left ventricle. Baseline values of end-systolic elastance, end-diastolic volume, end-systolic pressure, stroke work, stroke volume, and end-systolic elastance were recorded. Next, normal saline and 3.0V AVP were injected into the tongue to measure their effect on hemodynamic and cardiac function. Results: After 3.0V administration, systolic blood pressures at 10 and 15 min were higher than those of the control group; they increased at 10 min compared with those at baseline. The diastolic blood pressures at 5-15 min were higher than those of the control group; they increased at 5 and 10 min compared with those at baseline. The preload decreased at 5 and 10 min compared to that at baseline. However, the afterload increased from 5 to 15 min compared with that of the control group; it increased at 10 min compared with that at baseline. Stroke volume decreased at 10 and 15 min compared with that of the control group; it decreased from 5 to 15 min compared with that at baseline. Stroke work decreased from 5 to 15 min compared with that of the control group; it decreased from 5 to 15 min compared with that at baseline. Conclusion: Our results showed that 3.0 U/mL concentration of vasopressin resulted in increased blood pressure, decreased stroke volume and stoke work, decreased preload and increased afterload, without any effect on myocardial contractility.

사용자비용을 고려한 역사설계기준교통량 선정을 위한 시뮬레이션 기법의 적용 (The Application of Simulation Method for Selection of Design Volume to reflect User Cost in Station Planning)

  • 김용일
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 1999년도 추계학술대회 논문집
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    • pp.93-99
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    • 1999
  • The service level of Metro stations is affected by the design criteria such as platform area, width and length of stairways, and the number of turnstile, etc. The Korean station design process utilizes peak-hour volume as design volume. Hourly volume, however, can not explicitly account for the variation of traffic and consequently the variation of the level of service within the one-hour time period. Movements in various areas inside of stations are simulated with a queueing network under various operating conditions. A discrete simulation tool called SIMUL8 was utilized. Based on the results, peak volume for 15 minutes period was recommended as a preferred base volume over the peak-hour volume for station design purpose to realistically account for user delays under. Simulation runs also confirmed that escalators have positive effects on passenger processing capacity and on securing stability of passenger flows in stations.

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