• Title/Summary/Keyword: Pre-pressure

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Sasang Constitution may act as a Risk Factor for Hypertension and Pre-hypertension (고혈압 및 전기고혈압 위험요인으로서의 사상체질)

  • Jang, Eunsu;Jeong, Kyoung Sik;Lim, Sueun;Kim, Yunyoung
    • Journal of Sasang Constitutional Medicine
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    • v.34 no.1
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    • pp.37-45
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    • 2022
  • Objectives The purpose of this study was to reveal that Sasang constitution(SC) was associated with hypertension and pre-hypertension and could be a risk factor. Methods We introduced this study to educational personnel in D university in Daejeon, and 275 subjects joined this study. The SC classification was conducted with KS 15 questionnaire. The subjected measured the blood pressure with Jawon medical device automatically after 10 minute rest. The hypertension and pre-hypertension was classified by the guide of the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. The frequency analysis and T-test was used in general characteristics, and chi-square test was also used between SC and pre-hypertension and hypertension. Logistic regression was used to calculate the odds ratios (ORs) and 95% confidence interval (95% CI) for pre-hypertension and hypertension. Results The number of Taeeumin(TE), Soeumin(SE), and Soyangin(SY) was 142, 71, and 61 respectively. There was significantly different in systolic and diastolic blood pressure among SC types(p<.001). The distribution of the normal group, pre-hypertension and hypertension group by SC types was significantly different (p<.001). The ORs of TE was significantly increased (ORs 4.039, 95% CI=2.019-8.082 in pre-hypertension and ORs 4.235, 95% CI=1.581-11.348 in hypertension) compared with SE(p<.001), and after adjusting gender and smoking habit, it was still significantly different(p<.001). Conclusions It is possible that SC, especially TE could be a risk factor both pre-hypertension and hypertension.

The effect of deposition condition on the oxidation of TbFeCo thin films in facing targets sputtering system (Facing targets sputtering system에서 TbFeCo박막의 산화에 미치는 제조조건의 영향)

  • 문정탁;김명한
    • Electrical & Electronic Materials
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    • v.7 no.6
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    • pp.511-519
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    • 1994
  • The effect of the deposition conditions, such as the base pressure, working pressure, sputtering power, pre-sputtering, and deposition thickness in facing targets sputtering system(FTS), on the oxidation of the TbFeCo thin films was studied by investigating the magneto-optical properties as well as oxygen analysis by the AES depth profiles. The results showed that the base pressure did not affect the magnetic properties so much, probably due to the short flight distance of the sputtered particles. At the higher sputtering power and lower working pressure with pre-sputtering the oxidation of TbFeCo thin films was decreased. As the film thickness increased the TbFeCo thin films showed the perpendicular anisotropy from in-plane anisotropy overcoming the oxidation effect at the beginning of the sputtering.

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A Study of the Temperature Elevation Due to the Pre-flame Reaction in a Spark-Ignition Engine Using CARS Technique (CARS 측정 기술을 이용한 스파크 점화 기관에서의 화염 전 화학 반응에 의한 온도 변화에 관한 연구)

  • 최인용;전광민;박철웅;한재원
    • Transactions of the Korean Society of Automotive Engineers
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    • v.9 no.5
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    • pp.9-16
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    • 2001
  • End-gas temperatures were measured using CARS technique in a conventional DOHC spark- ignition engine fueled with PRF80. The measured pressure data were analyzed using band pass filter method. The measured CARS temperatures were compared with adiabatic core temperatures calculated from measured pressures. Significant heating by pre-flame reaction in the end gas zone was observed in the late part of compression stroke under both knocking and non-knocking conditions. CARS temperatures measured at 10 crank angle degree before knock occurrence was higher than adiabatic core temperatures. These results indicate that there exist some exothermic reactions in low pressure and temperature region. CARS temperatures began to be higher than the adiabatic core temperature when the end-gas temperatures reached look. The temperature elevation due to the pre-flame reaction correlated better with CARS temperature than with cylinder pressure.

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The Effects of Manual Therapy on Lower Extremity Alignment in Pelvic Malalignment

  • Jeon, Chang Keun;Han, Se Young;Yoo, Kyoung Tae
    • Journal of International Academy of Physical Therapy Research
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    • v.9 no.3
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    • pp.1543-1548
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    • 2018
  • The purpose of this study was to analyze the effects of manual therapy on lower extremity alignment in pelvic malalignment. The subjects were 20 adults with pelvic malalignment. They were divided into two groups: manual therapy group (n=10) and stretching exercise group (n=10). Each group performed the intervention two times per week for 4 weeks. The lower extremity alignment was measured by pelvic deviation, functional leg length inequality, and plantar pressure distribution, which were measured between pre- and post-test. In the result of pelvic deviation, there was a significant difference between the pre- and post-test of the manual therapy group and stretching exercise group. In the result of the functional leg length inequality, there was a significant difference between the pre- and post-test of the manual therapy group. In the result of plantar pressure distribution, there was a significant difference between the pre- and post-test of the manual therapy group. These findings suggest manual therapy improves the pelvic deviation, functional leg length inequality, and plantar pressure distribution in the pelvic malalignment.

Pre- and Postoperative Hemodynamic Studies in the Patients with Constrictive Pericarditis (수축성 심막염에 대한 심막절제술 전후의 수술방법에 따른 혈역학적 비교)

  • 조인택
    • Journal of Chest Surgery
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    • v.19 no.1
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    • pp.68-74
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    • 1986
  • 15 patients with constrictive pericarditis who underwent interphrenic pericardiectomy from January, 1981 to April, 1983 and 11 patients who underwent radical pericardiectomy from May, 1983 to September, 1984 were compared to the clinical improvement and the results of pre- and postoperative cardiac catheterization. In the group of partial pericardiectomy the pericardium was removed anteriorly from the left phrenic nerve to the right phrenic nerve and in the group of radical pericardiectomy the pericardium was removed from almost entire surface of the heart including diaphragmatic surface and posterior wall of the left ventricle. The following results were obtained. 1. Both group of the patients showed marked symptomatic improvement early after operation. 2. The central venous pressure was decreased significantly after operation in both group of the patients. 3. The right atrial mean pressure and pulmonary arterial mean pressure decreased significantly after operation in both group of the patients and there was no significant difference in the amplitude of decrease between the two groups. 4. The right ventricular end-diastolic pressure and left ventricular end-diastolic pressure were decreased postoperatively in both group of the patients and the patients of the radical pericardiectomy showed more decrease than the patients of interphrenic pericardiectomy, and in the group of radical pericardiectomy the right and left ventricular end-diastolic pressure were normalized postoperatively but in the group of partial pericardiectomy they showed abnormally high pressure persistently. 5. The ejection fraction showed normal level pre- and postoperatively in both group of the patients.

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Re-acceleration of Nonthermal Particles at Weak Cosmological Shock Waves

  • Kang, Hye-Sung;Ryu, Dong-Su
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.45.1-45.1
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    • 2011
  • Shock waves form in the intergalactic medium as a consequence of accretion, merger, and turbulent motion during the structure formation of the universe. They not only heat gas but also govern non-thermal processes through the acceleration of cosmic rays (CRs), production of magnetic fields, and generation of vorticity. We examine diffusive shock acceleration of the pre-existing as well as freshly injected populations of nonthermal, CR particles at weak cosmological shocks. Since the injection is extremely inefficient at weak shocks, the pre-existing CR population dominates over the injected population. If the pressure due to pre-existing CR protons is about 5 % of the gas thermal pressure in the upstream flow, the downstream CR pressure can absorb typically a few to 10 % of the shock ram pressure at shocks with the Mach number M<3. Yet, the re-acceleration of CR electrons can result in a substantial synchrotron emission behind the shock. The implication of our findings for observed bright radio relics is discussed.

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Finite Element Damage Analysis Method for J-Resistance Curve Prediction of Cold-Worked Stainless Steels (조사취화를 모사한 스테인레스강의 파괴저항선도를 예측하기위한 유한요소 손상해석기법)

  • Seo, Jun Min;Kim, Ji Soo;Kim, Yun Jae
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.14 no.1
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    • pp.1-7
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    • 2018
  • Materials in nuclear power plants can be embrittled by neutron irradiation. According to existing studies, the effect of the material property by irradiation embrittlement can be approximately simulated by cold working (pre-strain). In this study, finite element damage analysis method using the stress-modified fracture strain model is proposed to predict J-Resistance curves of irradiated SUS316 stainless steel. Experimental data of pre-strained SUS316 stainless steel material are obtained from literature and the damage model is determined by simulating the tensile and fracture toughness tests. In order to consider damage caused by the pre-strain, a pre-strain constant is newly introduced. Experimental J-Resistance curves for various degrees of pre-strain are well predicted.

Prediction of Bypass Transition Flow on Surface with Changing Pressure Gradient (압력구배가 변하는 표면 위의 Bypass 천이 유동의 예측)

  • Baek-Seong-Gu;Chung, Myung-Kyoon;Lim, Hyo-Jae
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.6
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    • pp.823-832
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    • 2002
  • A modified $textsc{k}$-$\varepsilon$model is proposed for calculation of transitional boundary-layer flows with changing pressure gradient. In order to develop the model for this problem, the flow is divided into three regions; pre-transition region, transition region and fully turbulent region. The effect of pressure gradient is taken into account in stream-wise intermittency factor, which bridges the eddy-viscosity models in the pre-transition region and the fully turbulent region. From intermittency data in various flows, Narashima's intermittency function, F(${\gamma}$), has been found to be proportional to $\chi$$^{n}$ according to the extent of pressure gradient. Three empirical correlations of intermittency factor being analyzed, the best one was chosen to calculate three benchmark cases of bypass transition flows with different free-stream turbulence intensity under arbitrary pressure gradient. It was found that the variations of skin friction and shape factor as well as the profiles of mean velocity in the transition region were very satisfactorily predicted.

Relation between Pressure Variations and Noise in Axial Type Oil Piston Pumps

  • Kim, Jong-Ki;Kim, Hyoung-Eui;Jung, Jae-Youn;Oh, Seok-Hyung;Jung, Seok-Hoon
    • Journal of Mechanical Science and Technology
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    • v.18 no.6
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    • pp.1019-1025
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    • 2004
  • Pressure variation is one of the major sources on noise emission in the axial type oil piston pumps. Therefore, it is necessary that the pressure variation characteristics of the oil hydraulic piston pumps be clarified to reduce the pump noise. Pressure variations in a cylinder at the discharge region and the pump noise were simultaneously measured with discharge pressures and rotational speeds during the pump working. To investigate the effects of the pre-compression and the V-notch in the valve plate, we used the three types of valve plates. In this research, it is clear that the pressure variation characteristics of axial type oil piston pumps is deeply related to the pre-compression and to the V-notch design in valve plate. Therefore, we could reduce the pump noise by using the appropriate pre-compression angle and the notch design that are between the suction port and the discharge port in valve plate.

Development of High Pressure & Temperature Constant Volume Chamber for Visualization Study of Fuel Spray and Combustion (연료 분무 및 연소 가시화 연구를 위한 고온 고압 정적 연소실 개발)

  • Kim, Kihyun
    • Journal of Power System Engineering
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    • v.21 no.3
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    • pp.12-18
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    • 2017
  • Diesel and gasoline engines will be used as main power system of automobiles. Recently, engine downsizing is widely applied to both gasoline and diesel engines in order to improve fuel economy and exhaust emissions. Engine downsizing means small engine combustion chamber with higher combustion pressure. Therefore, spray and combustion process should be investigated under these high pressure and temperature conditions. In this study, constant volume combustion chamber which enables easy optical access from six directions was developed. Combustion chamber was designed to resist maximum pressure of 15 MPa and maximum temperature of 2,000 K. Combustible pre-mixed mixture was introduced into combustion chamber and ignited by spark plugs. High pressure and temperature were implemented by combustion of pre-mixed mixture. Three initial conditions of different pressure and density were tested. High repeatability of combustion process was implemented which was proven by low standard deviation of combustion pressure.