• 제목/요약/키워드: Volume Control

검색결과 3,843건 처리시간 0.032초

2자유도 제어기법에 의한 전자 유압 서보계의 압력제어 (Pressure Control of Electro-Hydraulic Servo System by Two-Degree of Freedom Control Scheme)

  • 양경욱;오인호;이일영
    • Journal of Advanced Marine Engineering and Technology
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    • 제20권3호
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    • pp.110-120
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    • 1996
  • The purpose of this study is to build up the control scheme that promptly controls the pressure in a hydraulic cylinder having small control volume, using a PCV(proportional control valve) and a digital computer. Object pressure control system has the character to be unstable easily, because the displacement-flow gain of the PCV is so large considering comparatively small volume of the hydraulic cylinder and the time delay of response of PCV is long. Considering the above-mentioned characteristics of the object pressure control system, in this study, a control system is designed with two degree of freedom scheme that is composed by adding a feed-forward control path to I-PD control system, and the reference model is used to decide control parameters. And through some experiments on FF-I-PD, the validity of this control method is confirmed.

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트레드밀 훈련이 20대 남성 비만인의 폐기능 및 체질량지수에 미치는 영향 (The Effects on the Pulmonary Function and Body Mass Index of 20's Men Obesity after Treadmill Exercise)

  • 서교철;김현애
    • 대한통합의학회지
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    • 제4권4호
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    • pp.13-19
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    • 2016
  • PURPOSE : The purpose of this study was to determine whether tredmill exercise increases pulmonary function and decreases body mass index of the 20s obesity. METHOD : Thirty obesity in their 20s were randomly assigned to on experimental group (n=15) or control group (n=15). Over the course of four weeks, the experimental group participated in tredmill exercise for 30 minutes three times per week and the control group participated in auto-med exercise for 30 minutes three times per week. Subjects were assessed pre-test and post-test by measurement of pulmonary function (tidal volume, inspiration reserve volume, expiratory reserve volume, vital capacity) and body mass index. RESULT : Our findings show that the experimental group had significant difference in expiratory reserve volume and vital capacity and body mass index (p<.05). In the comparison of the two groups, the experimental group had higher pulmonary function and lower body mass index than the control group. CONCLUSION : In this study, the experimental group showed greater improvement in pulmonary function than the control group, which indicates that the tredmill exercise is effective at increasing the pulmonary function and body mass index 20s obesity.

회전교차로의 접근로 신호최적화를 통한 도입효과 분석 (Measurement of Effectiveness of Signal Optimized Roundabout)

  • 엄정은;정희진;배상훈
    • 한국도로학회논문집
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    • 제17권1호
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    • pp.91-98
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    • 2015
  • PURPOSES : Although signalized intersections have been considered the best way to control traffic volume in urban areas for several decades, roundabouts are currently being discussed as an alternative way to control traffic volume, especially when traffic is light. Because a roundabout's efficiency depends on the load geometry as well as the traffic volume, design guidelines for roundabouts are recommended only if the incoming traffic volume is very low. It is rare to substitute a roundabout for an existing signalized intersection in urban areas. This study aims to estimate the benefits from the transformation of an existing signalized intersection into a roundabout in an urban area. When there is a more moderate volume of traffic, roundabouts can be effectively used by optimizing signals located at an approaching roadway. METHODS : The methodologies of this paper are as follows: First, a signalized intersection was analyzed to determine the traffic characteristics. Second, the signalized intersection was transformed into a roundabout using VISSIM microscopic traffic simulation. Then, we estimated and analyzed the effects and the performance of the roundabout. In addition, we adjusted a method to improve the benefits of the transformation via the optimization of signals located at an approaching road to control the incoming traffic volume. RESULTS : The results of this research are as follows: The signal-optimized roundabout improved delays compared with the signalized intersection during the morning peak hour, non-peak hour, and evening peak hour by 1.78%, 12.45%, and 12.72%, respectively. CONCLUSIONS : According to the simulation results of each scenarios, the signal-optimized roundabout had less delay time than the signalized intersection. If optimized signal control algorithms are installed in roundabouts in the future, this will lead to more efficient traffic management.

당알코올을 첨가한 스펀지 케이크 반죽 및 제품 특성 (Batter and Product Characteristics of Sponge Cake Containing Sugar Alcohols)

  • 정월계;이정훈
    • 한국조리학회지
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    • 제16권4호
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    • pp.305-311
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    • 2010
  • 스펀지 케이크 제조시 설탕의 10%에서 40%까지 sorbitol과 maltitol로 대체하여 케이크 반죽의 비중 및 pH와 스펀지 케이크의 제품 특성으로 부피 및 조직감을 측정하였다. 반죽의 1차 비중은 대조구에 비하여 sorbitol과 maltitol을 첨가한 시험구들에서 낮았고, 그 첨가량이 많을수록 낮았다. 2차 비중도 같은 결과로 첨가량이 많을수록 낮아졌고, maltiol보다는 sorbitol에서 더 낮은 결과를 보였다. 반죽의 pH는 대조구에 비하여 sorbitol과 maltitol을 대체하였을 때 높았고, 대체량이 많을수록 높아졌다. 케이크의 부피는 대조구에 비하여 sorbitol과 maltitol을 대체한 시험구에서 크게 나타났다. 대체량이 20%까지는 sorbitol에서 부피가 컸고, 30% 이상에서는 maltitol에서 크게 나타났다. 스펀지 케이크의 조직감으로 경도는 대조구가 가장 높았고, sorbitol과 maltitol을 대체한 시험구에서 낮게 나타났다. Sorbitol과 maltitol의 비교에서는 sorbitol을 첨가한 시험구가 다소 낮은 경도 값을 보였다.

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호텔 영업장의손익분기점 분석에 관한 연구 (A Study on the Cost-Volume-Profit Analysis in the Food Service Operation)

  • 김기영;강종헌
    • 한국조리학회지
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    • 제3권
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    • pp.165-179
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    • 1997
  • Cost-volume-profit analysis shows the relationship between these factors. The figures expressed in a break-even chart can be used planning control and decision making. The relation ships can also be helpful in understanding how all costs must be covered in menu pricing. Involved in these relationship is the contribution to overhead and profit, or contribution ratio. This study used the food service operation of H hotel. Assumed the FC would be 10% of the High Volume, the VC would be 76% of the high volume. And in the CVP of individual meals, selected labor cost of the VC, assumed labor cost would be 35% of the volume.

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정상체중과 과체중 여대생을 대상으로 컵의 형태에 따른 인지량의 차이에 관한 연구 (Difference in Volume Perception according to Cup Shape in Normal Weight and Overweight Female College Students)

  • 이명옥;장은재
    • 대한영양사협회학술지
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    • 제20권1호
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    • pp.63-69
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    • 2014
  • The volume perception of water according to cup shape was examined in female college students divided into a normal weight group (<23 body mass index, n=51) and an overweight group (${\geq}$23 body mass index, n=48). The perceived water volume was recorded by participants after they observed the water volume in cups with different shape (highball and tumbler) and with different base height (high base and low base), which contained the same amount of water (150 ml). The normal weight group perceived a water volume of 238.5 ml (highball) and 201.6 ml (tumbler) for the high base cups. The overweight group perceived a volume of 245.6 ml (highball) and 188.8 ml (tumbler). For the low base cups, the normal weight group perceived a water volume of 207.8 ml (highball) and 104.1 ml (tumbler). The overweight group perceived a volume of 202.2 ml (highball) and 100.4 ml (tumbler). Both the normal weight and overweight groups perceived significantly more liquid in the highball cups compared to the tumbler cups. In addition, both groups perceived significantly more liquid in the high base cups compared to the low base cups. However, there were no significant differences in the estimated variance of perceived volume between the normal weight and overweight groups according to the cup shape and cup base height. In conclusion, cup shape and base height potentially affects volume perception. Therefore, modifying cup shape may be used in a weight control program to help control caloric beverage consumption.

열전달 특성을 고려한 공기압 압력제어계의 감압제어특성 해석 (Analysis of Decompression Control Characteristics of Pneumatic Pressure Control System Considering Heat Transfer Characteristics)

  • 장지성
    • 동력기계공학회지
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    • 제10권1호
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    • pp.90-95
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    • 2006
  • Pneumatic control systems have been mainly used as a high speed operating system. Therefore, state change of air in a control volume was assumed to be adiabatic change and, pneumatic control systems have been analyzed by using this assumption. Especially, when absolute value of pressure change in the control volume is small, there is a tendency to neglect effect of temperature change on pneumatic control system because temperature change owing to pressure change is small. In this study, an effect of temperature change of air on the decompression control process was analyzed by considering change of mass flow rate, and heat transfer characteristics between air in the chamber and the chamber wall. As a result, this study could confirm that a slight temperature change of the air in the pneumatic pressure control system can influence on the dynamic characteristics of pressure response, and pressure control performance.

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외인성 호르몬 처리가 강도다리 (Platichthys stellatus)의 배정에 미치는 영향 (Effect of Exogenous Hormones on Spermiation in the Starry Flounder Platichthys stellatus)

  • 임한규;김성연
    • 한국수산과학회지
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    • 제40권6호
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    • pp.374-379
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    • 2007
  • Two experiments were designed to examine short-term effects of human chorionic gonadotropin (hCG), and long-term effects of gonadotropin-releasing hormone agonist (GnRHa), $17{\alpha}-hydroxyprogesterone$ (17P), and $17{\alpha},20{\beta}-dihydroxy-4-pregnen-3-one\;(17,20{\beta}P)$, alone or in combination, on milt production of the starry flounder Platichthys stellatus. In the first experiment, fish were injected with either 200 IU hCG/kg body weight or the same volume of marine fish Ringer's solution (MFRS). In the second experiment, each fish was implanted with a blank cholesterol pellet (control), $200\;{\mu}g$ GnRHa, $500\;{\mu}g$ 17P, or $100\;{\mu}g\;17,20{\beta}P/kg$ body weight alone or in combination. In the first experiment, hCG injection resulted in an increase in the expressible milt volume and a decrease in the spermatocrit (Sct). After pellet implantation in the second experiment, the milt volume was increased in males treated with GnRHa, GnRHa+17P, or $GnRHa+17,20{\beta}P$. On day 7 after hormone pellet implantation, the milt volume began to increase, and on day 14, the milt volume in the $GnRHa+500\;{\mu}g$ 17P group was significantly higher than that in the control group. Compared with the control group, the hormone pellet-treated groups had a significant reduction in the mean Sct and sperm concentration (Sc) at day 7 after pellet implantation, while there were no differences in total sperm number. The results suggest that increases in milt volume are generally associated with decreases in Sct and SC, suggesting that the main mechanism for the increase in milt volume was milt hydration.

하이드로컬쳐 부피비와 화분용토에 따른 스킨답서스, 싱고늄의 실내습도 개선효과 (Effect of Scindapsus aureus and Syngonium podophyllum on the Improvement in Indoor Humidity by a Difference of Hydoroculture Volume Ratio and Pot Media)

  • 주진희
    • 한국조경학회지
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    • 제37권4호
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    • pp.94-99
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    • 2009
  • 본 연구는 하이드로컬쳐 실내녹화방법을 실내습도 개선의 중요한 수단으로 활용하기 위해, 관엽식물로 매우 보편화된 스킨답서스(Scindapsus aureus)와 싱고늄(Syngonium podophyllum)을 대상으로 하이드로컬쳐 식재 부피비율인 2%, 3%, 5% 차이와 3%의 동일한 하이드로컬쳐 식재대에서의 화분용토, 식물종의 차이에 따른 실내습도 변화를 실측하였으며, 그 결과는 다음과 같다. 하이드로컬쳐 부피비율에 따른 습도 변화에 있어서 스킨답서스의 경우, 식물이 투입하지 않았던 대조구에 비해 식물이 있는 생장상 내 상대습도가 높았다. 특히, 식물과 식재대의 용적비율이 높아질수록 습도가 높아졌다. 상대습도 25%인 대조구에 비해, 2%는 40%를, 3%는 45%를, 5%는 50%로 측정되었다. 싱고늄은 하이드로컬쳐 부피비율 2%는 40%를, 3%는 44%를, 5%는 46%로 각각 나타내어 대조구인 25%의 상대습도보다는 높았으나 부피비율에 따른 상대습도 차이는 확연하지 않았다. 하이드로컬쳐 식재대 내의 화분용토와 식물종에 따른 상대습도 변화를 살펴보면, 대조구인 하이드로볼 식재대 내의 하이드로볼 처리구에서 초기 상대습도가 다소 높았으나, 시간이 지남에 따라 물 식재대 내의 흙화분 처리구와 유사한 약 45%의 상대습도를 유지하였다. 물 식재대 내의 하이드로볼 처리구에서 상대습도가 약 30%로 나타났으며, 하이드로볼 식재대 내의 하이드로볼 처리한 산호수는 상대습도 약 38%로 측정되었다.

고등학교 남자배구선수들의 안정화운동에 대한 경.요부의 통증수준과 근육량, 체지방에 미치는 영향 (The Effect of Stability Exercise For Pain Level of Cervical and Lumbar Region, Muscle Volume and Fat Mass Composition in Body of High School in Man volleyball Player)

  • 원상희;전차선;유응식
    • 대한정형도수물리치료학회지
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    • 제15권1호
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    • pp.41-48
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    • 2009
  • Purpose: to program introduction the effects of stability sling exercise and common exercise of high school in man volleyball player. Methods: This study divided the subjects into a sling-exercise group and a common exercise group to compare after practicing exercises twice per week for 8 weeks (total 16 times). To compare the means of the experimental group and the control group on each variable, the ANOVA for repeated measure was used and if there was any significant difference across the measurement times, post-hoc comparisons were conducted for the difference. Results: The T-tests for group difference according to exercise type on each of the variables showed the results as follows. The pain in cervical region is experimental and control groups pain correlation were not significant(p>0.05). But lumbar region experimental and control groups were significant(p<0.05). Muscle volume was increased during 8weeks in experimental and control groups. But experimental and control groups muscle volume correlation were not significant(p>0.05). Conclusion: Fat Mass composition was decreased during 8 weeks in experimental and control groups. But experimental and control groups mass composition correlation were not significant(p>0.05).

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