• Title/Summary/Keyword: Pressure resistance

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General Characteristics, Antherpometric Values and Health-Related Factors according to Sasang Constitution among Elderly People in Rural Areas (농촌지역 50세 이상 성인 및 노인의 사상체질에 따른 일반적 특성, 신체계측 및 건강관련인자에 관한 연구)

  • Yang, Kyung-Mi
    • Journal of the Korean Home Economics Association
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    • v.50 no.2
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    • pp.39-51
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    • 2012
  • The purpose of this study was to elucidate the general characteristics, antheropometric values and health-related characteristics of the rural elderly population according to their Sasang constitutions. The participants in this study were 31 in Taeeumin group, 29 in Soyangin group, and 15 in Soeumin group. The present study was performed using self-administration questionnaires, antheropometric and biochemical analysis. There were no significant differences in height, weight, BMI, diastolic blood pressure and alcohol habits between the Sasang constitutions. In the analysis of physical activity, Soyangin had a higher value than the other groups. Compared with the other groups, Soeumin also had considerable resistance to stress($101.1{\pm}26.2$ point). Furthermore, in the analysis of fatigability caused by stress, Soeumin was mostly shown to feel less fatigue than the other groups. On the other hand, Taeeumin appeared to feel more fatigue. In the biochemical analysis of blood, there was no significant difference between Sasang constitutions.

Characteristics and Microstructure of Matrix Retaining Electrolyte in Phosphoric Acid Fuel Cell Prepared by Tape Casting (Tape Casting법으로 제조한 인산형 연료전지 전해질 매트릭스의 미세구조 및 특성)

  • 윤기현;허재호;장재혁;김창수
    • Journal of the Korean Ceramic Society
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    • v.31 no.4
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    • pp.375-380
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    • 1994
  • Matrices retaining electrolyte in phosphoric acid fuel cell were prepared with SiC to SiC whisker mixing ratios of 1:0.5, 1:1, 1:1.5, 1:2, 1:3 by tape casting method. When viscosity of the slurry was 5.9 poise and the SiC to SiC whisker mixing ratios were 1:1, 1:1.5, 1:2, the ranges of porosity, acid absorbency and bubble pressure were 80~90%, 2.5~6 and 700~2200 mmH2O, respectively. Those ranges are acceptable for a practical electrolyte-retaining matrix. With increasing the mixing ratio of SiC whisker to SiC, the porosity and the vol.% of large pores in the main pore size distribution which is between 1 and 10 ${\mu}{\textrm}{m}$, increased rapidly. Impedance spectroscopy was measured to know characteristics of matrix inside and contact region of matrix to catalyst layer. When the SiC to SiC whisker mixing ratio was 1:2, hydrogen ions were transported in the matrix most effectively because of high ionic conductivity and low activation energy due to high acid absorbency in spite of high interfacial resistance. The cell current density of the cell made using the matrix was 220 mA/$\textrm{cm}^2$ at 0.7 V.

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Preparation and Characteristics of a Matrix Retaining Electrolyte for a Phosphoric Acid Fuel Cell Using Non-volatile Solvent, NMP (비휘발성 용매(NMP)를 사용한 인산형 연료전지(PAFC)용 전해질 매트릭스 제조 및 특성)

  • 윤기현;양병덕
    • Journal of the Korean Ceramic Society
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    • v.37 no.1
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    • pp.26-32
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    • 2000
  • Preparation and characteristics of a matrix retaining electrolyte using SiC whisker, PES binder, and NMP(n-methyl-2-pyrrolidone) as a non-volatile solvent for a phosphoric acid fuel cell were investigated. The conditions of binder and plasticizer, and the effects of substituting a volatile solvent by a non-volatile solvent were also studied. The minimum amount of the binder was about 17 wt% for the proper bubble pressure and surrounding SiC whiskers. And the maximum amount of the plasticizer was about 10wt% to be fitted into the polymer chain of the binder. The matrix prepared by using a non-volatile solvent needed longer time to dry, and its pore size was smaller compared with that of the matrix prepared by using volatile solvent. The small pore size resulted in decrease of the overall pore volume. The ionic conductivity in the condition of the same thickness was decreased due to decrease of phosphoric acid absorbancy. As the internal resistance of the electrolyte increased, the fuel cell performance slightly decreased.

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A Simulation Study of Impedance Plethysmography for Diagnosing Deep Vein Thrombosis (Deep Vein Thrombosis 진단을 위한 Impedance Plethysmography의 시뮬레이션 연구)

  • Lee, Jeon;Lee, Kyoung-Joung
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.50 no.10
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    • pp.494-501
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    • 2001
  • In this study, the effects of vascular parameter changes and electrodes on VOP measurement based on IPG were simulated mathematically. For the evaluation of the effects of hemodynamic changes on VOP, a mathematical model, which consists of cardiovascular system model and venous occlusion model, was developed and the model solution representing the blood flow and pressure in measuring point was found by 2nd order Runge-Kutta method. And, with sensitivity coefficients obtained from finite element solution of electric field in measuring point, the effects of electrode system on measurement were evaluated. As increasing the resistance, the venous capacitance was not changed but the venous outflows were decreased and the decreased compliance reduced the venous capacitance. And, for several configurations of round electrodes and band electrodes, the sensitivity coefficients were computed using the electric field distribution along deep vein. In conclusion, the proposed mathematical cardiovascular model could be applied to the simulation study on the effects of hemodynamic parameters on DVT diagnosis with IPG. And, also the sensitivity coefficients could provide effective electrode configuration for exact measurement of VOP.

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What is body underweight?

  • Beeram, Eswari;Eshita, Ishrat Rafique
    • The Korean Journal of Food & Health Convergence
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    • v.5 no.5
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    • pp.33-36
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    • 2019
  • Arginine is one of the basic aminoacid found to be associated with histones and also one of the essential aminoacids now. Arginine is provided by diet, and also found to be synthesised in the body through intestinal-renal axis. Justification---BMI---Associated Risks-How to gain body weight---Healthy. Foods to Gain Weight Fast---High-Protein Vegetables and Fruits(with Image)-Recipes---Physical exercises-List of fruits and vegetables grown in Bangladesh with local names, English names and Botanical names-taxonomic family names. Arginine as drug was first approved by FDA and has recognised as a excellent dietary supplement for curing diseases like preeclampsia during gestation, diabetes and insulin resistance in obese patients. Preeclampsia is characterised by high blood pressure and proteinuria in gestational period of after 20 weeks. Severe preeclampsia is characterised by headaches, blurred vision, and inability to have high photovision, nausea and vomiting. L-Arginine along with Vit C and E are given as medical food to the patients and decrease in condition symptoms is the project now under phase II clinical trial. However the role of arginine in ameolirating preeclampsia symptoms is uncertain except with that of hypertension. Arginine is used to treat pain in sickle cell anaemia, lung damage, reperfusion injury, Trauma and shock but should be excluded during sepsis.

A Development on the Non-Photomask Plate Making Technology for Screen Printing (II) (포토마스크가 필요 없는 스크린 제판 기술 개발(II))

  • Park, Kyoung-Jin;Kang, Hyo-Jin;Kim, Sung-Bin;Nam, Su-Yong;Ahn, Byung-Hyun
    • Journal of the Korean Graphic Arts Communication Society
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    • v.26 no.2
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    • pp.45-54
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    • 2008
  • We have manufactured a photoresist which has excellent dispersity and good applying property due to 330 cps of viscosity for environment-friendly and economical maskless screen plate making. And the photoresist applied on the screen stretched was exposed with mask by UV-LED light source so we could manufacture the photoresist which proper for the UV light source. And it was developed by air spray with $1.7\;kgf/cm^2$ of injection pressure. Because of the excellence of power and resolution of the UV-LED light sourse, the pencil hardness and solvent resistance of curing photoresist film were excellent as those of conventional photoresist film. Moreover the $100{\mu}m$-width stripe image which has sharp edges was formed. So we confirmed a possibility of dry development process by air spray method.

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A Development on the Non-Photomask Plate Making Technology for Screen Printing (III) (포토마스크가 필요 없는 스크린 제판 기술 개발(III))

  • Kang, Hyo-Jin;Park, Kyoung-Jin;Kim, Sung-Bin;Nam, Su-Yong;Ahn, Byung-Hyun
    • Journal of the Korean Graphic Arts Communication Society
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    • v.26 no.2
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    • pp.55-64
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    • 2008
  • We designed a UV-LED exposure system which has 365nm dominant wavelength due to the environment-friendly and economical maskless screen plate making. And the photoresist applied on the screen stretched was exposed without mask by beam projector with UV-LED light source. Then it was developed by air spray with $1.7\;kgf/cm^2$ of injection pressure. The pencil hardness and solvent resistance of curing photoresist film were excellent as those of conventional photoresist film and the maximum resolution of line image formed by maskless screen plate making. was $100{\mu}m$, so we could establish the possibility of environment-friendly maskless screen plate making technology. But the sharpness of the patterns were ${\pm}40{\mu}m$ since the exposure system for maskless plate making has weak light intensity and the diffusion of light.

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Expression of Vascular Endothelin-1 and Nitric Oxide Synthase in Fructose-fed Hypertensive Rats (과당식이 고혈압 흰쥐에서 혈관 Endothelin-1과 산화질소합성효소의 발현)

  • Paek, Yun-Woong;Kim, Myung-Hoon
    • Journal of Korean Physical Therapy Science
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    • v.9 no.4
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    • pp.45-52
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    • 2002
  • Rats that are fed a fructose-rich diet develop hypertension, insulin resistance, and hypertriglyceridemia. To elucidate whether altered expression levels of endothelin-1 and nitric oxide synthase are related to the development of insulin-resistant hypertension, we examined the present study. Male Sprague-Dawley rats were fed a fructose-rich diet for 5 weeks. Systolic blood pressure significantly increased in fructose-fed rats. While serum free fatty acid and plasma nitrite/nitrate levels did not significantly differ between the fructose-fed and control groups, plasma insulin and serum triglyceride concentrations significantly increased in the former. Endothelin-1 mRNA expression in the aorta increased in fructose-fed rats. Neither the protein expression of constitutive nitric oxide synthase nor that of inducible nitric oxide synthase were significantly affected by fructose feeding. However, nitrite/nitrate levels in the aorta were significantly increased. These results suggest that an increase in vascular endothelin-1 is an important contributing factor to the development of hypertension in fructose-fed rats. However, the vascular nitric oxide pathway may not be causally related to the development of fructose-induced hypertension.

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A Study for Characteristic and Manufacturing of Porous Ni/AC4C and Ni-Cr/AC4C Composites (다공질 Ni 및 Ni-Cr으로 강화한 AC4C 복합재료의 제조 및 특성연구)

  • Kim, Young-Hyun;Kim, Eok-Soo;Yeo, In-Dong;Lee, Kwang-Hak
    • Journal of Korea Foundry Society
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    • v.20 no.1
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    • pp.21-28
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    • 2000
  • Ni and Ni-Cr porous metals which are estimated to be easy to fabricate by squeeze casting are used as strengtheners for composite materials. As a matrix material, Al-7%wtSi-0.3 wt%Mg(AC4C) has been used. In case of Ni/AC4C and Ni-Cr/AC4C composite, $750^{\circ}C$ melt temperature and minimum 25 MPa squeezing pressure are needed to produce sound composite materials. The observation of interfacial reaction zone at various heat treatment condition showed that solutionizing temperature of above 520^{\circ}C$, the interfacial reaction zone increased proportionally with increasing heat treatment tim and reaction products formed by interfacial reaction are mainly composed of $Al_3Ni$ and $Al_3Ni_2$ phases. The tensile strength of Ni/AC4C and Ni-Cr/AC4C composite is lower than the matrix metal and this can be explained by the brittle intermetallic compounds formed at the interface of Ni and Ni-Cr reinforcements. But the properies of hardness, wear resistance and thermal expansion are better than the matrix due to the strengthening effect of Ni-Cr porous metals.

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An Approach to a Speed Estimation Method to Remove Speed Sensor of Underwater Robot's AC Drive Systems (수중로봇용 AC구동시스템의 속도센서 제거를 위한 속도추정법 연구)

  • 전봉환;임용곤;이판묵
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1998.05a
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    • pp.371-376
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    • 1998
  • This paper describes an approach to a speed estimation method to remove speed sensor of underwater robot's AC drive systems. AC motors have been widely used in the field of underwater robot's manipulator or propulsion system. Most of these AC motors for underwater use have usually filled oil to compensate the high pressure in deep-sea operation, where a resolver is adopted to feed back the speed of rotor But this kind of speed feedback devices gives rise to some defects arising from their mechanical complexity and numerous signal lines; a resolver needs 6 or 7 signal lines for proper operation. This paper presents a speed estimation method to improve these problems of induction motor, which is adopted as a prototype of AC motor. The proposed speed estimation method is based on the RFO(rotor flux orientation) vector control method of voltage-fed AC drives. Using the controller of voltage-fed AC drives, it is unnecessary to measure the voltage for the estimation of rotor speed, which reduces the effects of measurement error Numerical simulation is carried out to investigate the validity of the method and the effects of rotors resistance variation.

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