• Title/Summary/Keyword: linear pump

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Experimental Study on the Pressure Characteristics in the Cupping Therapy (부항요법(附缸療法)의 압력특성에 관한 실험적 연구)

  • Kim, Yang-Joong;Kim, Do-Ho;Yeom, Seung-Chul;Lim, Byung-Chuel;Choi, Youn-Sung;Lee, Geon-Hui;Kim, Hyung-Soo;Lee, Jai-Kyoo;Lee, Geon-Mok
    • Journal of Acupuncture Research
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    • v.25 no.1
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    • pp.121-130
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    • 2008
  • Objectives : Cupping therapy is a stimulation therapy similar to acupuncture and moxibustion with effects that differ depending on the degree of stimulus. To make the strength of the skin objective in cupping therapy for this study, we measured negative pressure in the cupping jar and calculated the expansion rate of the skin. Subjects and Methods : In this study, we experimented with cupping therapy jars made for sale and used in clinics. We studied the pressure in the jars and the changes on the skin surface by measuring properties. We used commercial jars of four different volumes and diameters and tried to discover the properties on the size of the jar. Results : The results of experiment with the cupping therapy are as follows: 1. The lowest pressure in a jar was measured at $-600{\sim}610mmHg$, and the number of operating of vacuum pump for reaching lowest pressure was increased recording where the volume of the jar would be big, but the lowest pressure was not increased recording where the size of that would be big. 2. As the vacuum pump continued to operate, the pressure gradient in the jar got smaller which shows that the expansion rate of the skin was not linear. The pressure gradient shows different operational numbers on the vacuum pump near 0mmHg/operation unrelated to jar volume. 3. When negative pressure worked on the jar, air in the jar decreased. The percentage of air gradually reduced as the negative pressure acted in the jar. For example, the percentage of skin was 37-66% when the negative pressure, reatched -500mmHg. According to out results, different test areas generate different percentages of air in the jar, presumably related to skin elasticity. This phenomenon was most pronounced with the smallest jars. 4. At -500mmHg, the expansion rate of the skin was 1.57-1.9 on the abdomen, and $1.52{\sim}1.68$ on the back. The expansion rate of the skin appeared greater when the jar was relatively small, and it appeared smaller when the jar volume was relatively large relatively.

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Hydraulic Eroperty of Groundwater Flow Controlled by Vertical Geologic Structure and its field Example (수직 지질구조에 의해서 지배되는 암반지하수 유동의 수리적 성질과 그 예)

  • 함세영;김형찬;임정웅
    • Journal of the Korean Society of Groundwater Environment
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    • v.5 no.2
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    • pp.101-109
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    • 1998
  • Hydraulic property of fissured aquifers often depends on geologic structure which acts main channel of groundwater flow. We treated theories of linear flow related to vertical geologic structure. Then, we analyzed the result of two pumping tests conducted in Okmyeong-ri area (Kyeongbook province) using fractal model and found hydraulic characteristic of the fissured aquifer in this area. According to the pump test analyses, groundwater flow around the holes (pumping well D9; observation wells C3 and D7) of test 1 is linear. and is controlled by vertical geologic structure with infinite length and infinitesimally small width. On the other hand, around the hole D10 (pumping well) of test 2, groundwater flow is pseudo-radial (n=1.9) or radial (n=2). Thus, the characteristic of fractured aquifer often shows variable groundwater flow spatially and temporally.

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Development of Water Demand Forecasting Simulator and Performance Evaluation (단기 물 수요예측 시뮬레이터 개발과 예측 알고리즘 성능평가)

  • Shin, Gang-Wook;Kim, Ju-Hwan;Yang, Jae-Rheen;Hong, Sung-Taek
    • Journal of Korean Society of Water and Wastewater
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    • v.25 no.4
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    • pp.581-589
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    • 2011
  • Generally, treated water or raw water is transported into storage reservoirs which are receiving facilities of local governments from multi-regional water supply systems. A water supply control and operation center is operated not only to manage the water facilities more economically and efficiently but also to mitigate the shortage of water resources due to the increase in water consumption. To achieve the goal, important information such as the flow-rate in the systems, water levels of storage reservoirs or tanks, and pump-operation schedule should be considered based on the resonable water demand forecasting. However, it is difficult to acquire the pattern of water demand used in local government, since the operating information is not shared between multi-regional and local water systems. The pattern of water demand is irregular and unpredictable. Also, additional changes such as an abrupt accident and frequent changes of electric power rates could occur. Consequently, it is not easy to forecast accurate water demands. Therefore, it is necessary to introduce a short-term water demands forecasting and to develop an application of the forecasting models. In this study, the forecasting simulator for water demand is developed based on mathematical and neural network methods as linear and non-linear models to implement the optimal water demands forecasting. It is shown that MLP(Multi-Layered Perceptron) and ANFIS(Adaptive Neuro-Fuzzy Inference System) can be applied to obtain better forecasting results in multi-regional water supply systems with a large scale and local water supply systems with small or medium scale than conventional methods, respectively.

The Linear Stability Derivatives by the Transient Maneuvering Method (과도응답법(過渡應答法)을 이용한 조종미계수(操縱微係數)의 추정(推定)에 관한 연구(硏究))

  • Seung-Keon,Lee
    • Bulletin of the Society of Naval Architects of Korea
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    • v.27 no.3
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    • pp.31-37
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    • 1990
  • To obtain the values of linear stability derivatives, both analytical and experimental methods are now proposed and in use. The experimental method is well known as the planar motion mechanism(PMM) test. Its concept is to drive the model with a prescrived frequency and amplitude of the motion and pick up the hydrodynamic forces. But this kind of method is inconvenient in case we want to know the stability derivatives in wider range of the frequencies. So a different method is attempted that with one test run, we can get the derivatives in wider range of the frequencies. This technique forces the impulsive motion on the model, using the power of the oil pressure pump. This kind of method was originated by Scragg, C.A., Cummins, W.E, or Frank, T., This resarch is a further development of such preceding works. Todd's series 60(Cb=0.7) 2.00M model is chosen for the test and the results are compared with Van Leeuwen's famous PMM test results.

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Analysis of Volatile Fatty Acids in Air by Dynamic SPME (Dynamic SPME를 이용한 공기 중 지방산 분석)

  • Yu, Mee-Seon;Yang, Sung-Bong;Ha, Nam-Ki
    • Journal of Environmental Science International
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    • v.19 no.12
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    • pp.1447-1454
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    • 2010
  • In this study, the detection limits of lower fatty acids in air were investigated by using Dynamic SPME(Solid Phase Micro-Extraction), i.e. improved Head Space - SPME method(HS-SPME). This Dynamic SPME, called SPDE(Solid Phase Dynamic Extraction), is the analytical method for volatile compounds in air with the extraction by using a stainless steel needle of which inner surface is coated with adsorption material and following the gas chromatographic analysis by inserting the needle into a injection port of GC and subsequently, desorption of the volatile compounds into a gas-chromatographic column. Extraction was carried out by passing the sample air through the needle with a suction pump which has been used for a detection tube. The result of measurement for the 6 lower fatty acids showed that the detection limits ranged from 0.10 ppm to 0.44 ppm and the linear correlation coefficients were over 0.99. Relative standard deviations obtained from 5 analytical repetition of a ca. 1.6 ppm standard mixture were in the range of 1.87%~2.47%. This method has been shown to be a adequate for the measuring C2~C5 fatty acids in air in the concentrations of over several hundreds ppb.

Development of a Low -Cost and Precise Liquid Metering Device for Automatic Nutrient-Solution Control (양액 자동조제용 액제 정밀계량 장치 개발)

  • 이정훈;류관희;이규철
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1997.12a
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    • pp.255-262
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    • 1997
  • A low-cost and precise metering device, which is suitable to automatic mixing of nutrient-solution for hydroponic culture, was developed for small-scale growers. The metering device was composed of three parts those were supply pumps, metering cylinders and venturi tube. Those parts were controlled by personal computer with time-based odoff control method. To verify the performance of the developed metering device, the relationship between operating time and discharge was examined and the accuracy of the developed metering device was compared with commercial metering pumps. The results of this study are as follows. 1. The correlation coefficient between the flow rate and operating time was 0.9999, and the linear regression equation computed was y=21.759x, where y is the discharge(g) and x is the operating time(s). 2. The developed device has greater accuracy than commercial metering pumps in terms of the full-scale error. Calculated errors for the developed metering device and two commercial pump were $\pm$0.3 %, $\pm$2.45 % and $\pm$1.38 % respectively. 3. Above results show developed metering device is a useful tool for nutrient-solution control system.

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A Study of Optimal Fuel-Mix Considering Power Generation Operation (발전기 출력특성을 고려한 최적전원구성 연구)

  • Jung, Young-Beom;Kim, Kil-Sin;Park, Chang-Ho;Yoon, Yong-Beom
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.10
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    • pp.28-37
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    • 2011
  • Though Korea has introduced CBP(Cost Based pool) power trading system since 2001, long-term Generation system planning has been executed by government for Cost minimization every 2 years. Until currently the model which is used for Generation system planning and best-mix only considers cost minimization and total yearly or quarterly electricity demand every year. In a view point of one day power supply operation, technical characteristics, like the ramp up/down rate of total generation system, minimum up/down time and GFRQ(Governor Free Response Quantity), are very important. this paper analyzes Optimal Fuel-Mix for 2022 Korea generation system satisfying these constraints of each fuel type and considering pump storage plants, construction cost and $CO_2$ emission charge Using MILP(Mixed Integer Linear Programming) method. Also the sensitivity analysis which follows in future power industry environmental change accomplished.

Efficient Diode Pumped High Power Nd:YAG Laser with a Gold Coated Flow Tube (금코팅 유리관 반사체를 이용한 다이오드 여기 고출력 고효율 Nd:YAG 레이저)

  • 이종민;문희종;이종훈;한재민;이용주
    • Korean Journal of Optics and Photonics
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    • v.9 no.3
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    • pp.186-190
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    • 1998
  • We fabricated a diode-side pumped high power Nd:YAG laser with a gold coated flow tube(diameter of 10mm) and three sets of 140W diode bar. The diameter of Nd:YAG rod was 6mm and its length was 130mm. We obtained 130W cw power from a linear resonator with an 11% output coupler, which corresponds to the slope efficiency of 43% and the optical efficiency of 31%. The measured beam quality factor(M$^2$) reached about 85 which is fairly large due to the large size of the rod. Thermal lensing of the rod was measured to be 5.3-7.4D/$kW_{pump}$ when the laser was operating.

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Homogeneous characteristics of CdSe quantum dots from absorption coefficient and its change (흡수 계수와 흡수 계수 변화 특성에 따른 CdSe 양자 구슬 구조의 균일성 조사)

  • Hwang, Young-Nam;Shin, Sang-Hoon;Park, Seung-han;Kim, Ung;Kim, Dong-Ho
    • Korean Journal of Optics and Photonics
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    • v.8 no.2
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    • pp.122-127
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    • 1997
  • The hexagonal wurtzite structure of CdSe quantum dots are investigated by X-ray diffraction experiment. The absorption peaks due to quantum confinement effect are observed in the linear absorption spectra. Absorption coefficient changes at the lowest transition are measured with pump wavelength at the lowest transition and at the next higher transition from which direct intraband transition is not allowed. The measured larger absorption changes at the lowest transition confirm that the selection rules of intraband transition resulting from quantum confinement effect are satisfied. From the experimental results, therefore, we concluded that the CdSe quantum dots can be described as homogeneous system.

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Experimental Investigation on Flow Characteristics of Chicken Blood in a Micro Tube Using a Micro-PIV Technique (마이크로 PIV를 이용한 미세튜브 내부 조류 혈액유동에 관한 실험적 연구)

  • Yeo, Chang-Sub;Ji, Ho-Seong;Lee, Sang-Joon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.11 s.254
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    • pp.1027-1034
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    • 2006
  • In order to investigate flow characteristics of chicken blood in a micro tube of 100$\mu$m in diameter, in-vitro experiments were carried out using a micro-PIV technique. The micro-PIV system consists of a microscope, 2-head Nd:YAG laser, 12 bit cooled CCD camera and a delay generator. Chicken blood with 40% hematocrit was supplied into a micro tube using a syringe pump. The blood flow shows clearly the cell free layer near the tube wall and its thickness is increased with increasing the flow speed. The hemorheological characteristics of chicken blood, including shear rate and shear stress were estimated from the PIV velocity field data obtained. Since the aggregation index of chicken blood is less than 50% of human blood, non-Newtonian flow characteristics of chicken blood are smaller than those of human blood. As the flow rate increases, the degree of flatness in the velocity profile at the center region is decreased and the parabola-shaped shear stress distribution becomes to have a linear profile. Under the same flow rate, chicken blood shows higher shear stress, compared with human blood.