• Title/Summary/Keyword: Positive Pressure Measurement

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Study on the Gas Tight Shut-off Valve of NBC Shelter using Positive Pressure Measurement and Chemical Detection Module (양압측정 및 화학탐지 모듈을 적용한 화생방 방호시설의 가스차단밸브에 관한 연구)

  • Park, Hyoung-Keun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.7
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    • pp.417-422
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    • 2017
  • One of the most frightening aspects of weapons of mass destruction (WMD) is their ability to cause death in very small quantities without being visible to the public. The military authorities are making considerable effort to ensure the survivability of the combatants in the event of NBC(Nuclear, Biological and Chemical) contamination. Therefore, in this study, modules were developed for the measurement of the positive pressure and for the detection of the chemicals used for the control of the various shut-off valves used in an NBC shelter. In addition, a high performance gas tight shut-off valve was developed that can overcome the disadvantages associated with manual manufacturing, such as the occurrence of defective products and high manufacturing cost. By applying the positive pressure measurement and chemical detection modules, this valve was able to be used to control the facility. The developed gas-tight shut-off valve maintained airtight characteristics at a pressure loss of 28[Pa] at the prescribed wind velocity and an internal pressure of 30[kPa]. It is expected to be possible to control the gas-tight shut-off valve through the remote measurement of the positive pressure, thereby ensuring the foreign independence of import substitution and defense related technology in the future. In addition, by installing these valves in all of the intake ports or exhaust ports connected to the outside of the NBC shelter, it is possible to prevent the damage resulting from the rapid inflow of the storm pressure caused by conventional weapons and nuclear explosions, thereby protecting the people and equipment in the shelter.

Occurrence Mechanism and Characteristics of Pressure Pulsation in a Positive Displacement Hydraulic Turbine (용적형수차의 압력맥동 발생기구 및 특성에 관한 연구)

  • Choi, Young-Do
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.8
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    • pp.947-953
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    • 2007
  • Occurrence of pressure pulsation in positive displacement hydraulic turbine is one of the principal problems which should be cleared to improve the turbine performance and to put the turbine to practical use. Therefore, present study is tried to examine the occurrence mechanism and characteristics of the pressure pulsation CFD analysis and experimental measurement are implemented in this study to clarify the phenomena of unsteady pressure pulsation. The results show that occurrence reason of the pressure pulsation is not only due to a series of opening and closing of the chamber formed between rotor and casing wall but also due to the variation of rotational speed of following rotor. The pressure pulsation causes torque variation and the curve patterns of the torque variation conforms to that of the pressure pulsation. Pressure in the chamber is equal to the averaged value of inlet and outlet pressures. Sudden pressure decrease by accelerated through-flow between lobe and casing wall results in torque loss.

Nursing Students' Hearing Levels and Blood Pressure Measurement Accuracy (간호대학생의 청력수준과 혈압측정의 정확도)

  • Kim, Heeyoung;Chung, Young Hae;Kim, Yun Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.23 no.3
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    • pp.275-282
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    • 2016
  • Purpose: This study was done to examine the relationship between nursing students' hearing levels and accuracy of blood pressure (BP) measurements. Methods: Participants were 107 students who had finished their fundamental nursing practice and clinical practicum and who used earphones. Data were collected from October 13 to November 30, 2014 and from April 30 to May 19, 2015. Students' hearing thresholds were examined using an audiometer. Students were assigned to take two BP measurements on BP measurement training simulators, but only the second measurement was used for analysis. Results: All nursing students' hearing levels were within normal range, and there was no significant difference found among the settings for diastolic blood pressure. However, there were significant differences between low systolic blood pressure (SBP) (below 120mmHg) and high SBP (over 140mmHg) (z=9.02, p=.011). Measurement error in SBP showed a positive correlation with hearing threshold in the right ear at frequencies of 1000Hz and 500Hz. Conclusion: Findings indicate that BP measurement error is correlated with hearing threshold at some frequencies. To reduce measurement error, nursing students should be provided with health education about hearing and to improve training for students, further studies need to examine other factors influencing BP measurement error.

The Correlation of Foot Pressure with Spinal Alignment in Static Standing (정적 기립 자세에서 족저압 분포와 척추 정렬과의 상관관계 연구)

  • Lim, Jae-Heon;Ko, Hyo-Eun
    • PNF and Movement
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    • v.12 no.1
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    • pp.13-17
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    • 2014
  • Purpose: To determine the normative data for the correlation of spinal, pelvic parameters with foot pressure in the young subjects. Methods: The subjects of this study were 39 patients in healthy adults. The Formetric-III was used to measure of spinal alignment. The pedoscan was used to measure of foot pressure. The correlation of trunk imbalance, trunk inclination, lateral deviation with foot pressure. The foot pressure measurement was consisted of maximal/mean pressure, weight contribution. Result: There was a negative correlation of trunk inclination with Max_R. There was a negative correlation of trunk inclination with Max_R. There was a positive correlation of trunk imbalance with Max_L. There was a positive correlation of lumbar lordosis with Mean_R_front, Lt. posterior weight distribution. There was a negative correlation of lumbar lordosis with Lt., Rt. in distribution There was a negative correlation of pelvic tilt with Mean_R_front, Lt. posterior weight distribution. There was a positive correlation of pelvic tilting with Rt. weight distribution, Lt. posterior weight distribution. There was a negative correlation of pelvic torsion with Lt. weight distribution, Rt. posterior weight distribution. There was a negative correlation of pelvic rotation with Lt. weight distribution, Lt. posterior weight distribution. Conclusion: The data obtained from the study may be used for future studies related to correlation of the spinal, pelvic deviation with foot pressure.

Physiological and psychological effects of nature-based outdoor activities on firefighters in South Korea

  • Sang-Eun Lee;Heon-Gyo Kwon;Jisu Hwang;Hyelim Lee;Dawou Joung;Bum-Jin Park
    • Korean Journal of Agricultural Science
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    • v.51 no.1
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    • pp.9-23
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    • 2024
  • This study investigates the physiological and psychological effects of a nature-based outdoor activity program in an environment reflecting the characteristics of forest and coastal areas on 30 firefighters (average age: 40.4 ± 9.8 years) who are frequently exposed to dangerous situations. Blood pressure, pulse pressure, and heart rate variability were used as physiological measurement indicators, and the Korean versions of PANAS (positive affect and negative affect schedule), WEMWBS (Warwick-Edinburgh mental well-being scale), and PRS (perceived restorativeness scale) were used as psychological measurement indicators. For four days and three nights, the participants experienced programs at Hallyeohaesang Nature Center and the surrounding mountains, seas, and islands, utilizing forest resources such as trekking on forest trails, walking barefoot, taking aromatic footbaths, meditating in forest oxygen domes, and lying on relaxation chairs, and programs utilizing marine resources such as taking a boat to an island, walking on forest trails with seascape views, and sailing on a yacht. Participants' systolic blood pressure and pulse pressure decreased, and participants' positive emotions increased and negative emotions decreased after the program. There was a statistically significant increase in mental well-being and perceived restorative environment. Through this study, it was found that nature-based outdoor activity programs based on forest and marine resources are effective in physiological and psychological stability of firefighters. It is hoped that the results of this study will be applied to other high-risk workers for PTSD, who have high stress levels, by combining forest healing and marine healing, and expanding the scope and diversity of programs in more diverse environments and conditions.

Anthropometry, Blood Pressure, Salt Threshold and Salt Preference of Children of Orphan in Seoul and Kangnung (사회복지시설 아동의 성장발달, 혈압, 짠맛에 대한 역치 및 최적염미도에 관한 연구)

  • 김은경
    • Journal of Nutrition and Health
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    • v.27 no.2
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    • pp.181-191
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    • 1994
  • This study was designed to evaluate anthropometric measurement, blood pressure, salt threshold and salt preference of children living at orphan home in Seoul and Kangnung. Anthropometric data of the subjects were slightly lower than the Korean standards, and those of children in Seoul were slightly higher than those of children in Kangnung. There were no differences in salt threshold and salt preference between Seoul and Kangnung. Blood pressure had positive correlation that partialled out of age with various anthropometric measurements(body weight, mid-arm circumference, girth of chest, BMI and body surface area), but did not correlated to salt threshold and salt preference.

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Effects of the Body Shaping Foundation on Blood Flow and Wearer Comfort for Middle-aged Women (시판 체형보정용 파운데이션이 중년여성의 혈류 및 착용 쾌적감에 미치는 영향)

  • Kim, Nam Yim;Park, Gin Ah
    • Journal of the Korean Society of Clothing and Textiles
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    • v.45 no.3
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    • pp.495-509
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    • 2021
  • The study investigated the effects of five commercial body shaping foundation items on clothing pressure, blood flow, body shaping effectiveness, and wearer satisfaction for middle-aged women. The study measured clothing pressure at each of the 10 designated measurement points for twelve subjects wearing the foundations. Blood flow changes were recorded and body shaping effectiveness was analyzed by comparing differences in girth when wearing and not wearing the foundations. The subjects rated wearer comfort along a 7-point Likert scale. The results were that clothing pressure was present at all measurement points, and all foundations placed the least pressure on the anterior underbust girth. In addition, clothing pressure was high in the order of the lateral, posterior, and anterior areas. As clothing pressure increased, blood flow and velocity decreased and overall wearer satisfaction was assessed to be less comfortable. Body shaping effectiveness was evident across all the items, as all decreased girth measurements significantly. In conclusion, the appropriate level of clothing pressure provided by experimental foundations which is positive for blood flow and has an excellent body shaping effect was found to be between 0.53 and 1.77 kPa.

On the Analytical Model of Automotive Steering Hoses Containing Tuner and Its Practical Application (튜너 내장 자동차 조향호스의 해석 모델과 실용적 응용)

  • Lee, J.C.;Oh, S.H.
    • Transactions of The Korea Fluid Power Systems Society
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    • v.6 no.1
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    • pp.1-9
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    • 2009
  • This study presents an analytical model of an automotive steering hose containing tuner(flexible spiral metal tube) to reduce the ripple pressure induced by steering vane pump. The double-wall side branch composed in a steering hose containing tuner was analogically considered as a filter in a conduit. Specialized test equipment was manufactured for the estimation of speed of sound in a conduit and measurement of amplitude ratio between the propagated ripple pressures of inlet and outlet of the steering hose. Experimental data of entire frequency ranges can be obtained through the test once in short time. The results of three points' measurement method and cross-correlation method to estimate the speeds of sound in a hose, tuner, and side branch respectively reveal that cross-correlation method can be used practically. The results of simulation and experiment were so close, especially in the range of engine idling speed, that the proposed analytical model in this study was validated. Sensitivity analyses and experiments show that longer tuner is preferable, and that the positive-positive composition of the steering hoses containing tuner is superior to others to attenuate ripple pressure.

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Alternating Pressure Profile Characteristics of Powered Pressure Ulcer Preventing Devices (동력형 욕창예방제품의 교대부양 압력 프로파 특성)

  • Won, Byeong-Hee;Song, Chang-Seop
    • Journal of the Ergonomics Society of Korea
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    • v.29 no.4
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    • pp.639-646
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    • 2010
  • The APAM's quantitative effectiveness and comparative study in preventing and treating pressure ulcer has not been sufficiently evaluated mainly because of uncertainty of pressure load input and lack of interpretation of dynamic perfusion recovery characteristics of soft tissue. The purpose of this paper was to quantify and analyze the alternating pressure characteristics of APAM as a preventive measure for pressure ulcers. To quantify the alternating load to human body, we introduced alternating pressure profile concept and developed parametric model of the profile. Regarding pressure level and cycle time, 3 global and 7 local periodic parameters were used to define the profile such as light, standard, typical and heavy duty profile shape. Pressure impulse ratio of light duty is the lowest but pressure fluctuation is significantly high. For the same duty shape, contact conditions are changed with alternating cycle time and more dramatically in shorter alternating cycle time conditions. We can conclude that if we use shorter alternating cycle time on APAM's operation we can get more positive effects regarding to inflated contact time condition. We proposed the quantitative methods on tissue viability study of external loading by simultaneous measurement of interface pressure and tissue perfusion with proper alternating pressure profile conditions.

Effects of Exercise and Calcium Intake on Blood Pressure and Blood Lipids in Postmenopausal Women (운동과 칼슘 섭취량이 폐경 여성의 혈압과 혈중 지질에 미치는 영향)

  • 최미자
    • Journal of Nutrition and Health
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    • v.34 no.4
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    • pp.417-425
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    • 2001
  • The purpose of this study was to confirm that regular physical exercise habit and calcium intake play a role in reducing the risk of cardiovascular disease, particularly to confirm that regular exercise is important in reducing serum lipid levels in postmenopausal women. Subjects were classified into regular exercise group(more than 3 times/wk, more than 30 min per exercise) and non-regular exercise group. A convenient frequency method was used to assess the nutritional intake of subjects. Anthropometric measurement such as body weight and height, and blood pressure were measured. There was no significant difference between non-regular exercise group and regular exercise group in energy intake and calcium intake. The total cholesterol and LDL-cholesterol concentrations in non-regular exercise group were significantly higher than those in regular exercise group. There were no significant correlations between age or weight with blood lipids and blood pressure in regular exercise group, while there were significant positive correlations between age or weight with blood lipids and blood pressure in non-regular exercise group. The levels of serum cholesterol, triglyceride, blood pressure and atherogenic index increased with age in non-regular exercise women. The blood pressure in low total Ca intake/plant Ca intake ratio group was significantly higher than that in high total Ca intake/plant Ca intake ratio group. There was a highly significant positive correlation between Ca intake and HDL-cholesterol in non-regular exercise women. And, there was a highly significant negative correlation between Ca intake and blood pressure in regular exercise women. The results suggest that increased habitual physical activity and calcium intake should be recommended by way of decreasing blood lipids and blood pressure in postmenopausal women. (Korean J Nutrition 34(4) : 417∼425, 2001)

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