• Title/Summary/Keyword: volume effects

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

  • 박현우;박종호;신필권;심우건
    • Journal of KSNVE
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    • v.9 no.2
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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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The Effects of Interferential Current Therapy on Blood Flow in upper limbs (간섭 전류 자극이 상지 혈류변화에 미치는 영향)

  • Park Rae-joon;Park Young-han
    • The Journal of Korean Physical Therapy
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    • v.15 no.4
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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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Anti-inflammation, Anti-Development and Curative Effects of Oyaksunki sangamibang on the Collagen-Induced Arthritis in Rats (오약순기산가미방의 항염작용과 Collagen 유발 관절염의 발생억제 및 치료효과)

  • Lee Chan-Bum;Oh Min-Suck
    • The Journal of Korean Medicine
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    • v.26 no.3 s.63
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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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Effects of Volume and Product Flexibilities on Hospital's Performance (수량 및 제품유연성이 의료조직의 성과에 미치는 영향)

  • Park, Bo-Young;Sohn, Byung-Kyu
    • The Journal of the Korea Contents Association
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    • v.11 no.3
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    • pp.389-402
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    • 2011
  • Previous research on the management of health care organization has heavily focused on health care quality and operational efficiency, whereas this research deals with flexibility, an important strategic priority in the field of operations management. Particularly, this research analyzes the effects that internal and external resources of volume and product flexibilities have on the organization's financial performance. Survey data from various types of sampled domestic hospitals have been collected using the developed questionnaire and analyzed with a regression model. The results show that volume flexibility based on internal resources has not only main effects but also interaction effects with internal and external resources of product flexibility. However, volume flexibility based on external resources is not shown to have any effect on performance. The explanation and managerial implications from the results are discussed.

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

  • 이승우;문갑태;홍성인
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2002.05a
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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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Effects of Raw Materials for Papermaking and Physical Treatment on the Pore Structure and Paper Properties (제지 원료의 특성 및 물리적 처리가 종이의 기공 구조 및 물성에 미치는 영향)

  • Won, Jong-Myoung;Nam, Ki-Young;Chung, Soon-Ki
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.39 no.4
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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.

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

  • Lee, Jong-Young;Kwon, Ki-Rok
    • Journal of Pharmacopuncture
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    • v.14 no.3
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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.

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

  • 박석환
    • Journal of Environmental Health Sciences
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    • v.29 no.3
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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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    • v.22 no.1
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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.

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

  • 김용일
    • Proceedings of the Korea Society for Simulation Conference
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    • 1999.10a
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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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