• Title/Summary/Keyword: pressure history

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Awareness, Treatment, Control, and Related Factors of Hypertension in Gwacheon (과천시민의 고혈압 인지, 치료, 조절과의 관련요인)

  • Choi, Youn-Hee;Nam, Chung-Mo;Joo, Mi-Hyun;Moon, Ki-Tae;Shim, Jee-Seon;Kim, Hyeon-Chang;Suh, Il
    • Journal of Preventive Medicine and Public Health
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    • v.36 no.3
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    • pp.263-270
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    • 2003
  • Objectives : To identify the factors related to awareness, treatment, and control of hypertension in a Gwacheen population. Methods : This study surveyed 1,176 Gwacheon residents older than 40 years, and measured blood pressure using a standardized guideline in 1999. The study subjects were 473 adults (175 males, 295 females) with hypertension defined as a systolic blood pressure $\geq$140 mmHg, diastolic blood pressure $\geq$90 mmHg or reported treatment with antihypertensive medication. Information on awareness, treatment, and control of hypertension, and sociodemographic and health-related factors .was collected through person-to-person interviews with a structured questionnaire. Results : Overall, 252 (53.3%) of hypertensive subjects were aware of their condition, of whom as many as 193 (76.6%) were being treated, and 81 (42.0%) had their blood pressure controlled at the recommended level (<140/90 mmHg). However, of the 473 subjects found to have hypertension, only 40.8% were being treated, and 17.1% were under control. There were no significant differences in the proportions of awareness, treatment, and control of hypertension. In multiple logistic regression models, awareness of hypertension was positively associated with age and family history of hypertension in females. Control of hypertension was also positively associated with haying a partner and marital status in females.. Conclusion : These findings demonstrate that much greater efforts on improving awareness, treatment, and control of hypertension are needed, even in urban community settings, considering related factors such as a9e, family history, and marital status. However, these factors should be further investigated for their causal relationship.

Effect of Calcium Supplementation on Blood Pressure Response to Dietary Soldium Level in Normotensive Young Korean Women with Family History of Hypertension (칼슘의 보충섭취가 식이 나트륨 섭취수준에 따른 혈압 변동에 미치는 영향)

  • 이정원;이은양;이보경
    • Journal of Nutrition and Health
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    • v.32 no.6
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    • pp.661-670
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    • 1999
  • Effects of Ca supplementation on blood pressure(BP) response to dietary Na level were studied in 15 normotensive healthy college women with family history of hypertension. All subjects, randomly divided into 3 groups, ate low Na diet(1816mg/day) prepared in the laboratory during the first 2 weeks and normal Na diet(4064mg/day) of their own home for the next 8 weeks. The one group received daily 1g Ca supplement at both low and normal Na diet periods, the second group took daily 1g Ca supplement only at normal a diet period, and the last group took placebo during both periods. Average Ca and energy intakes at the basal of and during the trial ranged 450-600mg and 1735-1878kcal, respectively. Systolic/diastolic BP was decreased by 9.2-9.8/4.4-4.5 mmHg during low Na diet period and was increased again during next normal Na diet period. However simultaneous Ca supplementation during both low and normal Na diet period suppressed the elevation of systolic/diastolic BP occurred at normal Na diet period. Ca supplementation only at normal Na diet peroid did not affect the BP elevation. The increase of serum Ca and Ca/Mg ratio and the decrease of serum Na and Na/K ratio might be related to the BP lowering effects of Ca supplementation. In conclusion, Ca supplement could attenuate BP elevation induced by increasing Na intake. The BP lowering effect of Ca supplementation was not appeared at low Na intake. Further studies were needed to make it certain. Low Na intake was also confirmed as an effective diet control for lowering blood pressure.

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Flame Spread Mechanism of a Blended Fuel Droplet Array at Supercritical Pressure

  • Iwahashi, Takeshi;Kobayashi, Hideaki;Niioka, Takashi
    • Journal of the Korean Society of Combustion
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    • v.7 no.1
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    • pp.15-22
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    • 2002
  • Flame spread experiments of a fuel droplet array were performed using a microgravity environment. N-decane, 1-octadecene, and the blends (50% : 50% vol.) of these fuels were used and the experiments were conducted at pressures up to 5.0 MPa, which are over the critical pressure of these fuels. Observations of the flame spread phenomenon were conducted for OH radical emission images recorded using a high-speed video camera. The flame spread rates were calculated based on the time history of the spreading forehead of the OH emission images. The flame spread rate of the n-decane droplet-array decreased with pressure and had its minimum at a pressure around half of the critical pressure and then increased again with pressure. It had its maximum at a pressure over the critical pressure and then decreased gradually. The pressure dependence of flame spread rate of 1-octadecene were similar to those of n-decan, but the magnitude of the spread rate was much smaller than that of n-decane. The variation of the flame spread for the blended fuel was similar to that of n-decane in the pressure range from atmospheric pressure to near the critical pressure of the blended fuel. When the pressure increased further, it approached to that of 1-octadecene. Numerically estimated gas-liquid equilibrium states proved that almost all the fuel gas which evaporated from the droplet at ordinary pressure consisted of n-decane whereas near and over the critical pressure, the composition of the fuel gas was almost the same as that of the liquid phase, so that the effects of 1-octadecene on the flame spread rate was significant.

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History and Characteristics of Risk Perception and Response Related to Science: Focused on Blood Pressure (과학에 관련된 위험 인식과 대응의 역사와 특징 -혈압을 중심으로-)

  • Wonbin Jang;Minchul Kim
    • Journal of The Korean Association For Science Education
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    • v.43 no.6
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    • pp.549-562
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    • 2023
  • The current society is in the VUCA era, where various risks produced by humans are spread along with the development of science and technology. There is a need to increase the level of risk literacy of citizens to strengthen their daily preparedness to respond to these risks. For this on, it is necessary to reconsider the role of science education so that risks can be perceived and responded to scientifically and objectively. Accordingly, in order to investigate the role of science education in a risk society, this study reviewed the history of risk perception and response related to science and analyzed its characteristics. In this process, perception and response to risks arising from blood pressure were analyzed in three contexts (historical context, curriculum context, textbook context). For historical context, journals registered in SCIE were selected as research subjects among journals where research related to the history of knowledge of the heart and cardiovascular system was conducted. Papers with the keywords 'hypertension' and 'history' were selected from the journals, and changes in perception and responses related to blood pressure were compared and analyzed by period. The curriculum context is analyzed from the 1st national curriculum to the 2022 revised curriculum, and content elements and achievement standard related to blood pressure were compared and analyzed. It was confirmed that risks arising from blood pressure were not included from the 1st to the 6th national curriculum, and that risks arising from blood pressure were included from the 7th national curriculum (excluding the 2009 revised curriculum). For the textbook context, the 7th national curriculum BiologyⅠ, the 2015 revised curriculum Life ScienceⅠ, and Health were selected, and through text mining, keywords that representing curriculums and textbooks were selected, and the presentation of risk perception and response was analyzed based on the keywords. And by analyzing the figures and tables presented in the textbook, the characteristics of risk perception and risk response were derived. This study is meaningful in that it was able to confirm the role of risk perception and response in science education.

Dilatometer test for evaluating deformation characteristics in sand (사질토의 변형특성 평가를 위한 딜라토미터 시험의 활용)

  • Lee, Moon-Joo;Hong, Sung-Jin;Lee, Woo-Jin
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.241-252
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    • 2010
  • This study investigates the application of dilatometer test for evaluating the deformation characteristics of granular soil. $K_D$ is the most sensitive to the stress history among CPT and DMT measurements, and $E_D$ and $q_c$ are observed to be similarly affected by the stress history. The coefficient of at-rest earth pressure($K_0$) is an indirect measure evaluating the stress history of granular soil. A relation using only DMT indices provides appropriate prediction of $K_0$ values. Although penetration of dilatometer inevitably induces the failure of cementation bonds, $E_D$ reflects the deformation characteristics of undamaged cementation relatively well. Therefore, a slightly better prediction of M value for cemented sand is achieved by using $E_D$ rather than $q_c$. Because of the weaker particle strength of calcareous sand compared than quartz sand, the majority of sand particles adjacent to dilatometer probe will be crushed during penetration. The particle crushing will induce the less contraction of the dilatometer membrane during penetration, consequently, the smaller $K_D$ and $E_D$ of calcareous sand.

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The distribution of Hyperlipemia and sequential changes of serum lipid levels to cerebral vascular accident (뇌졸중(腦卒中) 환자(患者)에 있어 고지혈증(高脂血症)의 분포(分布) 및 혈중지질(血中脂質)의 경시적(經時的) 변화(變化))

  • Jeon, Sang-Yun;Gang, Hwa-Jeong;Hong, Seok;Jeong, Yeong-Hae
    • The Journal of Internal Korean Medicine
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    • v.19 no.2
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    • pp.60-80
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    • 1998
  • In 123 examples of admission patients at Dongshin university oriental medical hospital circulatory internal medicine, we sequently investigated serum lipid, at admission state, 2th and 4th weeks. The results were as follows; 1. In the case of 123 stroke patients, only 12cases were related to Hyperlipemia. So stroke was not related to Hyperlipemia significantly. 2. According to sex, woman has more significant results in the T-cholesterol and LDL-cholesterol. 3. According to the living Zone, Triglyceride of the city zone group washigher than that of the contryside zone significantly. 4. According to the history of drinking and smoke, the patients who have the history of drinking and smoke had a significant remark in T-cholesterol and LDL-cholesterol. 5. In the case of patients like eating meat, it was significant gain of HDL-cholesterol. 6. In the patients who had past history of Hypertension, the value of Triglyceride is significantly low, and sequently as blood pressure decreased, serum lipid value decreased too. 7. In the patients who had past history of D.M., the value of Triglyceride is significantly high, and sequently as blood sugar value decreased, serum lipid value decreased too. 8. In the case of patients treated He-Ne laser, Triglyceride was decreased significantly. 9. In the case of treating the stroke patients, serum lipid had non-significant decrease value.

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Measurement of Surface Pressure Fluctuations on a Rotating Blade Using a Digital Recording Device (Digital Recording Device를 ol용한 회전중인 블레이드 표면의 압력섭동 측정)

  • Yun, Jung-Sik;Kang, Woong;Sung, Hyung-Jin
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.29 no.10 s.241
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    • pp.1119-1129
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    • 2005
  • A new measurement system of wall pressure fluctuations on a rotating machinery, composed of digital recording device, was developed and evaluated. The small-sized digital recording device was attached on the rotating machinery and then was detached for data reduction. In order to obtain the system transfer function of the digital recording system, a dynamic calibration was performed utilizing the signal from a 1/8 inch B&K microphone as input. The time history of the unsteady pressure was then reconstructed from the output of the sensor by using this transfer function. The reconstructed pressure signals showed good agreement with the reference signal in both temporal and spectral sense. This sensor was then used to measure the wall pressure fluctuations on a rotating blade. An array of microphones were installed on the blade in the circumferential and radial directions. Various statistical moments were obtained from the measurement data set. Comparison of these quantities with the existing studies demonstrated satisfactory agreement. These tests give credence to the relevance and reliability of this device for applications in more complicated turbulent rotating machineries.

Investigation of Droplet Vaporizatio Phenomena in High Pressure Environments (고압에서의 액적의 증발현상에 관한 연구)

  • Lee, Hyun-Chang;Baek, Seung-Wook
    • Journal of the Korean Society of Combustion
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    • v.13 no.3
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    • pp.17-23
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    • 2008
  • The spray combustion and spray cooling depends on droplet evaporation. So, evaporation model for spray has been requested and lots of investigation has been done and various reliable models have been developed also for last few decades. In the present study, One dimensional quasi-steady spherically symmetric droplet evaporation model for micro-gravity is developed. The gas phase was assumed as steady state and the thermophysical properties are calculated as a function of temperature, pressure and composition and the properties used in the model was validated by NIST web data and overall evaporation history results was compared with experimental results by Nomura and Qasim and gave satisfactory agreements. Through this model, diverse phenomenon was investigated, especially regarding the effects of ambient pressure and temperature. The effects of pressure for the droplet evaporation time were studied. The high pressure increased the droplet surface temperature and made effect on the evaporation time depend on atmospheric temperature. The role of the ambient temperature was investigated and explained. The basic investigation for the evaporation process according to variation of droplet diameter and surface temperature were also investigated and the well-known phenomena, like D-square-law, were reported, too.

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An Experimental Study on Slamming Phenomenon by Forced Impact (강제 입수에 의한 슬래밍 현상에 관한 실험적 연구)

  • Nahm, J.O.;Kang, H.D.;Chung, J.Y.;Kwon, S.H.;Choi, H.S.
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2006.11a
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    • pp.392-395
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    • 2006
  • This paper presents the experimental results at slamming phenomenon. The air pressure cylinder was used to ensure repeatability of the impact. The results showed that the adopted experimental technique was very excellent in terms of repeatability when is compared to that of the free drop tests. The pressure time histories, magnitude of peak pressure and the behavior of jet spray were obtained. The flat specimen was tested for various incident angles. To estimate the incident speed of the specimen high speed camera was used. The high speed camera was also useful tool in understanding the behavior.

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Vaporization of Hydrocarbon Fuel Droplet in High Pressure Environments (고압 환경하에서 탄화수소 연료 액적의 기화특성 연구)

  • Kim, Sung-Yup;Yoon, Woong-Sup
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.127-132
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    • 2003
  • A study of high-pressure n-heptane droplet vaporization is conducted with emphasis placed on equilibrium at vapor-liquid interface. General frame of previous rigorous model[1] is retained but tailored for flash equilibrium calculation of vapor-liquid interfacial thermodynamics. The model is based on complete time-dependent conservation equations with a full account of variable properties and vapor-liquid interfacial thermodynamics. The influences of high-pressure phenomena, including ambient gas solubility, thermodynamic non-ideality, and property variation on the droplet evaporation are investigated. The governing equations and associated moving interfacial boundary conditions are solved numerically using a implicit scheme with the preconditioning method and the dual time integration technique. And a parametric study of entire droplet vaporization history as a function of ambient pressure, temperature has been conducted. Some computational results are compared with Sato's experimental data for the validation of calculations. For low ambient temperatures, the droplet lifetime first increases with pressures, then decreases for high pressures. For higher ambient temperatures, the droplet lifetime increase with less amplitude than that of low ambient temperatures, which then decreases with more amplitude than that of low temperatures. The solubility of nitrogen can not be neglected in the high pressure and it becomes higher as the pressure goes up.

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