• Title/Summary/Keyword: Over-pressure

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A Study of a Heavy Rainfall Event in the Middle Korean Peninsula in a Situation of a Synoptic-Scale Ridge Over the Korean Peninsula (종관규모 기압능이 한반도를 덮고 있는 기간에 중부지방에서 나타난 호우의 발생 원인)

  • Kim, Ah-Hyun;Lee, Tae-Young
    • Atmosphere
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    • v.26 no.4
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    • pp.577-598
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    • 2016
  • Observational and numerical studies have been carried out to understand the cause and development processes of the heavy rainfall over the middle Korean Peninsula during 0300 LST-1500 LST 29 June 2011 (LST = UTC + 0900). The heavy rainfall event occurred as the synoptic-scale ridge extended from Western Pacific Subtropical High (WPSH) was maintained over East Asia. Observational analysis indicates that the heavy rainfall is mainly due to scattered convective systems, formed over the Yellow Sea, traveling northeastward across the middle peninsula without further organization into larger systems during 0300 LST-0800 LST, and mesoscale convective systems (MCSs) over the Yellow Sea, transformed into a squall line, traveling eastward during 0800 LST-1500 LST. Organization of convective systems into MCSs can be found over the area of mesoscale trough and convergence zone in the northern end of the low-level jet (LLJ) after 0600 LST. Both observational and numerical investigations indicate that a strong LLJ extended from the East China Sea to the Yellow Sea plays an essential role for the occurrence of heavy rainfall. The strong LLJ develops in between the WPSH and a pressure trough over eastern China. Numerical experiments indicate that the land-sea contrast of solar heating of surface and latent heating due to convective developments are the major factors for the development of the pressure trough in eastern China. Numerical study has also revealed that the mountainous terrain including the mountain complex in the northern Korean Peninsula contributes to the increase of rainfall amount in the middle part of the peninsula.

The Antihypertensive Effect of Gyeok pal sang saeng yeok chim Acupuncture Treatment in Hypertension Patients (고혈압 환자에서 격팔상생역침범(隔八相生易鐵法)의 혈압강하 효과)

  • Han, Chang-Hyun;Han, Choong-Hee;Shin, Mi-Suk;Shin, Seon-Hwa;Choi, Sun-Mi
    • Journal of Acupuncture Research
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    • v.23 no.4
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    • pp.49-60
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    • 2006
  • Objectives : The aim of the study was to investigate the antihypertensive effect of Gyeok pal sang saeng Yeok chim Acupuncture in hypertensive patients. Methods : We measured the blood pressure of the patients who were admitted in the Oriental Medical Clinic of Brother from 13th February 2006 to 13th May 2006. We included the patients only in case of the systolic blood pressure was over 120mmHg or diastolic blood pressure was over 80mmHg, thirty patients were treated by Gyeok pal sang saeng Yeok chim Acupuncture. In order to evaluate the effect of the Gyeok pal sang saeng Yeok chim Acupuncture, the blood pressure and pulse rate were measured before and after Acupuncture procedure total 10 times. Results : There were significant decrease in the systolic blood pressure and significant decrease in the diastolic blood pressure treated by Gyeok pal sang saeng Yeok chim Acupuncture 10 times but pulse rate was not significantly decreased. The effect of Gyeok pal sang saeng Yeok chim Acupuncture by measurement time on blood pressure were follows: In a systolic blood pressure and diastolic blood pressure was gradually deceased significantly from 1st to 10th but pulse rate was not significantly decreased. Conclusion : These results suggest that Gyeok pal sang saeng Yeok chim Acupuncture is effective in decreasing the systolic and diastolic blood pressure.

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Differential in Married Women's Perceived Time Pressure by Employment : Testing the Effects of Couple Time Use and Housework Outsourcing (기혼여성의 취업여부에 따른 시간압박감과 관련요인의 차이 : 아내의 시간, 남편의 시간, 그리고 가사노동 사회화의 효과)

  • Cha, Seung-Eun
    • Journal of Families and Better Life
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    • v.33 no.5
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    • pp.37-53
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    • 2015
  • The purpose of this study is to examine the differences in perceived time pressure between employed and non-employed married women in Korea. The sample of married couple from the Korean Time Use Survey 2009 (n = 6,948 couple diaries) was used to examined the difference in the level of perceived time pressure over the life cycle of two group. This study also investigated the married women's time use, husband's time use as well as hour of domestic outsourcing and whether such factors are associated with lowering perceived time pressure of married women. Results showed employed wives felt almost 3 times more time pressed than non-employed wives, and the gap mostly remained over different life cycles. Total work hours were associated with increasing the time pressure of both groups of women, while regenerating time was associated with ameliorating time pressure. The result suggests that the time pressure gap between employed and non-employed wives can be partly due to the relative length of total labor hours and regenerating time among the two groups. Ordered logit analysis revealed that husband's paid work hours were not associated with wive's feeling rushed, but husband' unpaid work hours were positively linked with time pressure of their wives. Results indicated if employed or non-employed wives are feeling very busy, there is a high chance that husband might give them some help. We found employed wives spend more hours on housework outsourcing, and purchasing goods for housework was not associated with lowering the feeling of pressure of employed wives. There were both similarity and difference in factors associated with women's feeling pressed among employed and non-employed wives. It implies that social process and it's strategies to alleviate the time pressure can be different by women's employment status.

Effectiveness of Hwang-gu acupuncture treatment in hypertension patients; case report (황구침법(黃丘鍼法)을 이용한 고혈압 환자의 혈압강하 효과에 대한 증례보고)

  • Han, Chang-Hyun;Hwang, Chi-Won;Shin, Mi-Suk;Shin, Seon-Hwa;Choi, Sun-Mi
    • Korean Journal of Acupuncture
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    • v.23 no.3
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    • pp.37-50
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    • 2006
  • Objectives : The aim of the study was to investigate the antihypertensive effect of Hwang-gu Acupuncture in hypertensive patients. Methods : We measured the blood pressure of the patients who were admitted in the Oriental Medical Clinic of Brother from 25th November 2005 to 27th March 2006. We included the patients only in case of the systolic blood pressure was over 140mmHg or diastolic blood pressure was over 90mmHg, Twenty two patients were treated by Hwang-gu Acupuncture. In order to evaluate the effect of the Hwang-gu Acupuncture, the blood pressure was measured before and after Acupuncture procedure total 4 times, 10times. Results : There were a significant decrease in the systolic blood pressure and significant decrease in the diastolic blood pressure by Hwang-gu Acupuncture 4 times. The effect of Hwang-gu Acupuncture by measurement time on blood pressure were follows: In a systolic blood pressure was gradually deceased significantly from 1st to 4th but diastolic blood pressure was significantly decreased after 2nd and 4th only. Conclusions : These results suggest that Hwang-gu Acupuncture is effective in decreasing the systolic and diastolic blood pressure.

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A Study on the Performance Characteristics of Low Pressure Hydraulic Circuit of Common Rail System (커먼레일 시스템용 저압 유압회로의 성능특성에 관한 연구)

  • Lee, Choon-Tae
    • Journal of Power System Engineering
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    • v.18 no.6
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    • pp.51-57
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    • 2014
  • High pressure common rail injection technology has revolutionized the diesel industry. Over the last decade it has allowed engine builders to run higher injection pressures as much as above 1,300bar in order to increase engine efficiency, while reducing emissions. This common rail system has low pressure circuit which is consist of low pressure pump, cascade overflow valve and flow metering unit. The low pressure pump's purpose is to feed fuel oil to the high pressure pump. The cascade overflow valve keeps pressure in front of the metering unit constant and provides lubrication for the high pressure pump. The metering unit, known as the MPROP or fuel pressure regulator, regulates the maximum flow rate delivers to the rail. In this paper, we have investigated the performance characteristics of each components and total low pressure circuit of common rail system.

Analysis on Industrial Structure of Hospitals that Have Over 500 Beds (500병상 이상 규모 병원의 산업구조 분석)

  • 조우현;전기홍
    • Health Policy and Management
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    • v.8 no.2
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    • pp.25-57
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    • 1998
  • In order to assess the attractiveness of the hospital industry, the competitive environment of the industry was analyzed. With the employment of Michael Porter's five forces model' the deciding factor was examined and applied to evaluate the intensity of the competitiveness in the hospital industry, and then the structure and attractiveness in hospital industry was assessed. The subject of this study was hospitals that have over 500 beds. Main findings are as follows. 1. Out of 5 factors deciding competitiveness, the pressure from newly opened hospitals and the competition between existing hospitals, were both high in intensity; this makes hospital industry less attractive. The pressure from the substitutes and the pressure from the negotiating power of consumers and suppliers were low; this makes hospital industry more attractive. 2. Overall intensity of competitive pressure pressure for existing hospital industry that have over 500 beds was rather low, consequently the attractiveness of the industry was evaluated quite high. These findings, however, were not solid enough to endorse the attractiveness of the industry. 3. It was understood that future industry would have bigger pressure/ competition so that the attractiveness for the relevant hospital industry would be decreased. This study has its limitations. As the evaluation of competitive factor was not grounded on quantitative data, its objectivity could be questioned. Also, the overall result of each factors could be distorted as it was calculated with same weight against individual factor. This study has its significance in that the specific hospital group was viewed as one industry, and its attractiveness as a potentially profitable industry in which worth investing was estimated, with all factors considered. With this key result, hospitals industustry could work out a plan to enhance the status of hospitals, allowing hospitals to get assistance in making strategic decisions such as mergers, cooperations, and new establishments.

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The Experimental Study on the Leakage of Automatic Pressure Differential · Overpressure Control Dampers (자동차압 · 과압조절형댐퍼의 누설량 실험 연구)

  • Shin, Pyung-Shik;Kim, Hak-Joong
    • Fire Science and Engineering
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    • v.29 no.6
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    • pp.71-75
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    • 2015
  • Recently, Since buildings are bigger and higher, the damage of human life can be increased by fire flame and smoke in fire. Smoke control system is necessary to decrease this damage. Therefore, Air supply pressurization smoke control system is applied to vestibule of escape stairway. NFSC requires pressure differential of 40 Pa~60 Pa, but pressure differential is over 60 Pa in the field. It is known that the cause of this over pressure differential is much leakage of damper. Over pressure differential can bad effect to escaper by pressurizing the door. Analyze the real leakage of damper by testing for identifying this problems. The result of testing, leakage is $0.090m^3/s{\sim}0.154m^3/s$. It is necessary to limit the leakage of dampers for safe of escapers.

Changed Relationship between Snowfall over the Yeongdong region of the Korean Peninsula and Large-scale Factors

  • Cho, Keon-Hee;Chang, Eun-Chul
    • Journal of the Korean earth science society
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    • v.38 no.3
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    • pp.182-193
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    • 2017
  • A typical snowfall pattern occurs over the east coastal region of the Korean Peninsula, known as the Yeongdong region. The precipitation over the Yeongdong region is influenced by the cold and dry northeasterly wind which advects over warm and moist sea surface of the East Sea of Korea. This study reveals the influence of large-scale factors, affecting local to remote areas, on the mesoscale snowfall system over the Yeongdong region. The National Centers for Environmental Prediction-Department of Energy reanalysis dataset, Extended Reconstructed sea surface temperature, and observed snowfall data are analyzed to reveal the relationship between February snowfall and large-scale factors from 1981 to 2014. The Yeongdong snowfall is associated with the sea level pressure patterns over the Gaema Plateau and North Pacific near the Bering Sea, which is remotely associated to the sea surface temperature (SST) variability over the North Pacific. It is presented that the relationship between the Yeongdong snowfall and large-scale factors is strengthened after 1999 when the central north Pacific has warm anomalous SST. These enhanced relationships explain the atmospheric patterns of recent strong snowfall years (2010, 2011, and 2014). It is suggested that the newly defined index in this study based on related SST variability can be used for a seasonal predictor of the Yeongdong snowfall with 2-month leading.

Pellet Fuel from Wood Biomass (목질바이오매스를 이용한 펠릿연료의 제조)

  • Han, Gyu-Seong
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.11a
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    • pp.521-524
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    • 2006
  • Recently, densified pollet fuel from wood biomass is widely used at North America and Europe as a regenerable and clean carbon neutral bioenergy. High-pressure compaction of sawdust of several species of wood to form a densified fuel was studied. Calorific and elemental analysis were carried out to assess pellet fuels Hot-press process was adopted for compact ion of sawdust and compaction was performed under prescribed condition. Densified fuels were evaluated by its oven-dry density and fines after 5-minute shaking test. The target density and fines of densified fuels were over $1.2g/cm^3$ and below 0.5%, respectively. When the press-temperature is over $60^{\circ}C$ densified fuels with density over $1.2g/cm^3$ and with fines below 0.5% can be produced. And the pressure over $1000kgf/cm^2$ was effect ive for this production.

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Antihypertensive effect of Meridian Tai Ji exercise treatment in hypertension patients (고혈압 환자에서 경락도인태극권의 혈압강하 효과)

  • Shin, Mi-Suk;Han, Chang-Hyun;Kang, Kyung-Won;Choi, Sun-Mi
    • Korean Journal of Oriental Medicine
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    • v.14 no.1
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    • pp.67-72
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    • 2008
  • Objectives : The purpose of the study was to determine the effects of a 4 weeks Meridian Tai Ji exercise treatment on blood pressure reducing in hypertensive patients. Methods : We measured the blood pressure of 3 patients who were visited in the Gwacheon Health center from 21th November 2007 to 17th December 2007. Eligible participants had systolic blood pressure ${\geq}$ 120 mmHg or diastolic blood pressure ${\geq}$ 80 mmHg with antihypertensive drug. Blood pressure measurements were after the patient had been in rest for at least 10 minute. Twelve sessions of Meridian Tai Ji exercise treatment over 4 weeks were performed in the patients. Blood pressure were measured twice before and after each session. Results : After 4 weeks, blood pressure reduction was observed in the treatment patients, with an average decline of systolic blood pressure up to 5.67 mmHg and diastolic blood pressure up to 0.17 mmHg. But, it was not statistically significant. Blood pressure increased between measurements taken before and after an Meridian Tai Ji exercise treatment session, although individual responses were quite variable. No significant difference was found in the immediate effect. Conclusion : Twelve sessions of Meridian Tai Ji exercise treatment do not seem to control hypertension. Further research is required to determine whether Meridian Tai Ji exercise treatment can enhance clinical management of hypertension if it is used in combination with more enrolled participants, over longer periods, or randomized controlled trial.

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