• Title/Summary/Keyword: pressure data

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A Study on Combustion Characteristics of the High Pressure Diesel Engine in Closed Cycle System (폐회로 시스템에서 고압 디젤엔진의 연소특성에 관한 연구)

  • 김인교;박신배
    • Journal of Advanced Marine Engineering and Technology
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    • v.26 no.4
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    • pp.457-463
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    • 2002
  • The closed cycle diesel engine is used in a closed circuit system which has no air breathing. The working fluid as intake mixture are consisted of oxygen, argon and recirculated exhaust gas in order to obtain underwater or underground power sources. In the present study, the high pressure diesel engine which can be operated by the closed cycle system with high intake pressure for increasing the net power rate is designed. It has been carried out to investigate the combustion characteristics of high pressure diesel engine according to the power rate. The maximum cylinder pressure and heat release rate were investigated. Also, major experimental data such as specific fuel consumption rate, oxygen concentrations, fuel conversion efficiency, polytropic exponent, and IMEP were compared with low pressure diesel engine experimental data.

An experimental study for prediction of the fluctuating pressure induced by a cavitating propeller (캐비티가 발생한 프로펠러의 변동압력 추정을 위한 실험적 연구)

  • K.S. Kim;I.S. Moon;K.Y. Kim;I.H. Song;J.T. Lee
    • Journal of the Society of Naval Architects of Korea
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    • v.36 no.1
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    • pp.47-52
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    • 1999
  • The influence of propeller revolution on measurement of fluctuating pressure is almost minimized in the KRISO cavitation tunnel and the measurement accuracy of fluctuating pressure acting on a flat plate due to a cavitating propeller is improved. The measurement data for Sydney Excess propeller is compared with the measurement results of other research institutes loading to the conclusion that KRISO data is so stable and reasonable. The fluctuating pressure data measured on a model ship and the prototype ship is compared with the data measured on the flat plate. The solid boundary factor, derived from a calculation based on a lifting surface theory, is applied to predict full scale pressure level from the experimental data on the flat plate, showing quite reasonable agreement with full scale data.

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Development of The Physical Pressure Monitoring System to Prevent Pressure Ulcers (욕창 방지를 위한 체압 모니터링 시스템 개발)

  • Lee, Ah-Ra;Jang, Kyung-Bae
    • IEMEK Journal of Embedded Systems and Applications
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    • v.6 no.4
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    • pp.209-214
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    • 2011
  • This study suggests a Healthcare System for elderly and disabled who have mobility impairment and use a wheelchair for long time. Seating long time in a wheelchair without reducing pressure causes high risk of developing pressure sores. Pressure sores come with great deal of pain and often lead to develop complication. Not only it takes time and effort to treat pressure sores but also increases medical expenses. Therefore, we will develop a device to help to prevent pressure sores by measuring pressure distribution while seating in a wheelchair and wirelessly send information to user device to check pressure distribution in real time. The equipment to measure body pressure is composed of FSR sitting mat which is a sensor measuring part and an user terminal which is a monitoring part. The designed mat is matrix formed FSR sensor to measure pressure. The sensor send measured data to the controller which is connected to the end of the mat, and then the collected data are sent to an user terminal through a bluetooth. Developing a pressure monitoring system will help to prevent those who have mobility impairment to manage pressure sores and furthermore relieve their burden of medical expenses.

The Relationship of Risk Assessment Using Braden Scale and Development of Pressure Sore in Neurologic Intensive Care Unit (Braden scale을 이용한 신경외과 중환자의 욕창 위험 요인 사정과 욕창 발생과의 관계)

  • Lee, Jong-Kyung
    • Korean Journal of Adult Nursing
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    • v.15 no.2
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    • pp.267-277
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    • 2003
  • Purpose: The purpose of this study was to evaluate the applicability of braden scale to assess pressure ulcer risk patients and to identify additional risk factors of pressure sores in an neurologic intensive care unit. Method: The subjects of this study were 66 patients in neurologic intensive care units. Data was prospectively collected from Sep. to Dec., 2002. Data were analyzed by mean, percentage, t-test, chi-square, discriminant analysis using Spss pc+. Result: The results of this study were as follows: 1) There was a significant difference between scoring of braden scale and pressure ulcer development. The subscales that predicted pressure ulcer development using braden scale only were sensory perception, moisture, mobility, friction & shear. By using these subscales, sensitivity was 86.7%, and specificity was 61.1%, and total hit ratio was 72.7%. 2) Additional pressure ulcer risk factors which showed significance for discriminating two group were protein, albumin, gender, level of consciousness, pattern of bowel elimination. By using the combination of these additional risk factors in addition to the braden scale, total hit ratio increased to 84.8%. Conclusion: This data suggest that albumin, protein, gender, level of consciousness, pattern of bowel elimination in addition to the braden scale should be included in the pressure sore assessment tool.

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A Study on the Effect of the Atmospheric Pressure in the Gas Flow Measurement (대기압이 가스유량측정에 미치는 영향에 관한 연구)

  • Chung, Jong-Tae;Ha, Young-Cheol;Lee, Cheol-Gu;Her, Jae-Young
    • 유체기계공업학회:학술대회논문집
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    • 2002.12a
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    • pp.363-369
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    • 2002
  • Orifice meter is the most widely used flowmeter in custody transfer between KOGAS and city gas companies. Absolute pressure value is needed to calculate the gas flow of orifice metering system, but the gauge pressure transmitters are mainly used in the field. In case that the gauge pressure transmitters are used, the fixed value as standard atmospheric pressure(101.325kPa) is applied for the absolute pressure value. The real, local atmospheric pressures of each metering station are different from the standard condition as the altitude and weather conditions. In this study the flow calculation errors were quantitatively analyzed through examining the atmospheric pressures of 50 stations of KOGAS. The data for analysis are such like the time data of supplied gas amount, the altitude of each metering station, the time data of atmospheric pressures and altitudes of each weather observatory. The results showed that the local atmospheric pressures were different from the standard value and the gas flow calculation errors were distributed between $-0.024\%{\~}0.025\%$ based on the supplied gas amount in the year 1999 and 2000.

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The Effect of auricular acupuncture pressure therapy on insomnia of elderly people (노인의 불면증에 대한 이압요법의 효과)

  • Sok, So Hyune;Kim, Kwuy Bun
    • Korean Journal of Adult Nursing
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    • v.12 no.2
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    • pp.222-233
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    • 2000
  • This study was conducted with a purpose to evaluate the effect of auricular acupuncture pressure therapy on insomnia of elderly and to suggest the auricular acupuncture pressure therapy as an independent nursing intervention. The study was unequvalance control group pretest-posttest experimental design and the data collection was done from 37 samples of experimetal group and 37 samples of control group which were random-assigned as 60 years-over elderly people who lived in seoul. Data were collected from November, 1999 to February, 2000. The tools used in the study were the auricular acupuncture pressure therapy for decreasing of insomnia, the scale of sleepness and self- satisfaction scale. The auricular acupuncture pressure therapy used in this study is a sort of the auricular acupuncture to decrease insomnia and self-satisfaction of sleep by pressured on applied auricular acupncture of upper auricular blood acupuncture site of insomnia. Data was analied by SPSS stastistics program. Conclusively, sleepness and self- satisfaction of sleep were measured higher in experimental group which applied this auricular acupuncture pressure therapy than control group which not applized(p=.000). Therefore, the auricular acupuncture pressure therapy can decrease frequent insonmia of elderly and increase self satisfaction of sleep, processingly can improve quality of life in the late stage. Futhermore, it can be developed as independent oriental nursing intervention

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Porosity Prediction of the Coating Layer Based on Process Conditions of HVOF Thermal Spray Coating (HVOF 용사 코팅 공정 조건에 따른 코팅층의 기공도 예측)

  • Jeon, Junhyub;Seo, Namhyuk;Lee, Jong Jae;Son, Seung Bae;Lee, Seok-Jae
    • Journal of Powder Materials
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    • v.28 no.6
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    • pp.478-482
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    • 2021
  • The effect of the process conditions of high-velocity oxygen fuel (HVOF) thermal spray coating on the porosity of the coating layer is investigated. HVOF coating layers are formed by depositing amorphous FeMoCrBC powder. Oxygen pressure varies from 126 to 146 psi and kerosene pressure from 110 to 130 psi. The Microstructural analysis confirms its porosity. Data analysis is performed using experimental data. The oxygen pressure-kerosene pressure ratio is found to be a key contributor to the porosity. An empirical model is proposed using linear regression analysis. The proposed model is then validated using additional test data. We confirm that the oxygen pressure-kerosene pressure ratio exponentially increases porosity. We present a porosity prediction model relationship for the oxygen pressure-kerosene pressure ratio.

Experimental Study on Performance Characteristics of High Speed Air Valve for Water Works (급수용 급속공기밸브의 성능특성에 관한 실험적 연구)

  • Lee, Sun Kon;Kaong, Sae Ho;Yang, Cheol Soo;Woo, Chang Ki
    • Journal of the Korean Society of Safety
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    • v.29 no.5
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    • pp.1-6
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    • 2014
  • When the fluid energy convert into kinetic energy due to water hammer, the propagation velocity of pressure wave appear. The propagation velocity of pressure wave(1050 m/s) of very fast could be damage to the pipeline system. If the occurrence of water hammer is due to down-pressure, the faster the air exhaust or supply device is needed. it is high Speed Air Valve. In this paper, Each 3.12, 3.13, 3.72, $3.74kg/cm^2$ pipeline pressure were setting, and then executed pressure rapid drop for obtaining a high Speed Air Valve Operating time and pressure change data. the result was that pipe line pressure stabilization time were each 0.98, 1, 1.22, 1.25 sec. In other words, that pressure drop experimental results pipe line pressure was equal to atmospheric pressure without negative pressure After about one second. The study result would be useful to pipe line system stability design because this data could be foresee pressure stabilization time.

Influence of time pressure on the purchase decision making process in apparel shopping

  • Moon, Ji-Young;Lee, Kyu-Hye
    • The Research Journal of the Costume Culture
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    • v.21 no.1
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    • pp.117-128
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    • 2013
  • Studies show that time pressure affects the purchase decision-making process of consumers. However, in the case of apparel shopping, few studies have looked into the influence of time pressure on the purchase decision-making process. This study aims to determine how perceived time pressure in apparel shopping, time pressure situations, and product type and the interactions between these variables influence the clothing purchase process. An empirical study was conducted among males and females in their 20s and 30s. Perceived time pressure in apparel shopping was measured using four items. Time pressure situations and product types were given in the form of scenarios. A $2{\times}2{\times}2$ experimental design was used, and perceived time pressure in apparel shopping, time pressure situations, and product type were used to create eight different situations. The dependent variables included decision-making speed, anticipated regret, and anticipated purchase satisfaction. Data from 512 subjects were collected through an online data collection. Results showed that the high perceived time pressure group and the shopping situation with time pressure involved a significantly high level of decision-making time, anticipated regret, and anticipated purchase satisfaction. Marketers must understand the real-time pressure situations of consumers.

Endochronic simulation for the response of 1020 carbon steel tubes under symmetric and unsymmetric cyclic bending with or without external pressure

  • Lee, Kuo-Long;Hsu, Chien-Min;Hung, Chao-Yu
    • Steel and Composite Structures
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    • v.8 no.2
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    • pp.99-114
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    • 2008
  • This paper presents the theoretical simulation of the response of 1020 carbon steel tubes subjected to symmetric and unsymmetric cyclic bending with or without external pressure by using the endochronic theory. Experimental data of 1020 carbon steel tubes tested by Corona and Kyriakides (1991) were used for evaluating the theoretical simulation. Several cases were considered in this study, they were symmetric bending without external pressure, symmetric bending with external pressure, unsymmetric bending without external pressure, and unsymmetric bending with external pressure. The responses of the moment-curvature, ovalization-curvature and ovalization-number of cycles with or without external pressure were discussed. It has been shown that the theoretical simulations of the responses correlate well with the experimental data.