• Title/Summary/Keyword: Profile effect

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구름요소의 프로파일 설계에서의 EHL해석의 작용

  • 박태조;김경웅
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1991.06a
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    • pp.50-54
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    • 1991
  • This paper shows the effect of axial profile on the elastohydrodnamic lubrication (EHL) behavior of axially profiled cylindrical roller. For two different type of profiles which have nearly similar elastostatic pressure distribution, the EHL results show large differences. Especially the difference in film shape is larger than that of pressure distribution. Therefore, the magnitude of the minimum film thickness should be a major criteria to design the axial profile of the roller and a new design procedure is presented which take into account the minimum film thickness as well as the pressure distribution.

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A Study on the technique of impact analysis against concrete target using Lagrangian and Smoothed Particle Hydrodynamics (라그란지안 기법과 입자완화동력학 기법을 이용한 콘크리트 표적 충돌해석 기법 연구)

  • 하동호
    • Journal of the Korea Institute of Military Science and Technology
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    • v.5 no.2
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    • pp.207-216
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    • 2002
  • In this paper, the study on the behavior of the deformation of brittle material, such as concrete, ceramic, was peformed by comparison of Lagrangian technique and Smoothed Particle Hydrodynamics using commercial nonlinear hydrodynamic numerical program, Autodyn_2D. The effect of SPH technique was proved by investigating the behavior of material deformation, velocity profile and pressure profile.

Analysis of Frictional Power Loss Due to the Effects of Elastic Deformation in the Piston Skirt Profile (탄성변형을 고려한 피스톤 스커트의 마찰 손실 해석)

  • 조준행;장시열
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2000.11a
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    • pp.385-396
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    • 2000
  • The secondary motion of piston occurs due to the transient forces and moments in the clearances between piston skirt and cylinder liner The motions are very related to the skirt profile and the magnitude of piston-pin offset. Above all, the elastic deformation is another major effect on the piston secondary motion that has not been considered in the previous researches. In this work, the effects of elastic deformation of the piston skirt on the secondary piston motion are studied for the frictional power loss by using commercial softares, PISDYN and ANSYS.

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Anti-gelling Effect of Poly(methacrylic acid, methyl methacrylate) on Cefuroxime Axetil Composition

  • Shim, Ji-Yeon;Wang, Hun-Sik;Kwon, Min-Chang;Park, Jun-Sang
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.237.1-237.1
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    • 2003
  • Cefuroxime axetil, a broad spectrum antibiotic, has been known to form a gelatinous mass in contact with aqueous media, which could lead to poor dissolution. Therefore, this study was conducted for removing the gelling phenomenon and thereby obtaining a favorable dissolution profile. We have found that the addition of poly (methacrylic acid, methyl methacrylate) could not only inhibit the tendency of cefuroxime axetil to form a gel but also showed the good dissolution profile compared to the formula without poly (methacrylic acid, methyl methacrylate). (omitted)

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Effects of Medical Nutrition Therapy on Food Habits and Serum Lipid Levels of Hypercholesterolemic Patients (영양교육이 고콜레스테롤혈증 환자의 식습관 및 혈청 지질 농도에 미치는 영향)

  • Kim, So-Yeon;Son, Jeong-Min;Jeong, U-Yeong
    • Journal of the Korean Dietetic Association
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    • v.11 no.1
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    • pp.125-132
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    • 2005
  • Hypercholesterolemia has been regarded as a major risk factor of coronary heart disease(CHD). CHD is increasing in recent years among Koreans due to westernization of lifestyle and dietary behaviors. In the United States, implementation of the National Cholesterol Education Program(NCEP) had resulted 40% decline in mortality from CHD. This study was designed to evaluate the effect of medical nutrition therapy on serum lipid levels and discuss the effective nutrition education contents. Thirty outpatients(Male 40%, female 60%) with hypercholesterolemia were educated by medical nutrition therapy(MNT) protocol. At first visit and after three months of MNT, we assessed serum lipid profile, body weight and surveyed general characteristics, lifestyle and food habits through questionnaire. After 12 weeks of MNT, there were significant reductions in serum cholesterol and low-density lipoprotein cholesterol(LDL-C). Foods habits and lifestyle were changed to the desirable patterns. These results indicate that lipid profile is improved by changes of dietary behaviors and lifestyle. Especially in case of obesity, cholesterol lowering effect of MNT was more powerful. Consequently, MNT is effective on reduction of serum lipids by behavior change in hypercholesterolemic patients.

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Property of fish school and vertical temperature profile of Tuna Purse Seine in the Western Pacific Ocean (서부태평양해역에서의 다랑어 선망어업의 어군성상과 연직수온)

  • 김형석
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.3
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    • pp.237-241
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    • 1999
  • It was investigated that the condition of fishing ground gave what kind of effect school type in relation to the property for the target school after the vertical temperature profile and school type were observed when tuna purse seiner for tuna purse seine was operated in the western pacific Ocean around the equator between December 12, 1993 and January 26, 1994. The results are as follows;1. This study divided fish schools associated with drift objects, a one targeted-operation, and the pelagic migrating fish schools that are another one for the property. The total of 23 operations were complected including 6 that targeted fish schools associated with drift objects and 17 that targeted pelagic migrating fish schools. It was known that the main operation was conducted on pelagic migrating fish school.2. Average and standard deviation of the depth of the surface mixing layer was 86.0m and 13.8m for fish schools associated with drift objects. 61.6m and 13.0m for pelagic migrating fish schools, respectively. The average depth of the surface mixing layer of the pelagic migrating fish schools was lower when compared to the fish schools associated with drift objects however the concentration of standard deviation was higher than those fish schools associated with drifted objects. Accordingly, it was assumed that the effect of vertical temperature profile for pelagic migrating fish school was higher than the fish schools associated with drift objects.

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Effect of Refrigerated and Thermal Storage on the Volatile Profile of Commercial Aseptic Korean Soymilk

  • Kim, Hun;Cadwallader, Keith R.;Jeong, Eun-Jeong;Cha, Yong-Jun
    • Preventive Nutrition and Food Science
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    • v.14 no.1
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    • pp.76-85
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    • 2009
  • This study determined the effect of refrigerated and thermal storage on the volatile profile of commercial aseptic soymilk. Volatile components in commercial aseptic soymilk stored either under refrigerated ($4^{\circ}C$) or thermal ($55^{\circ}C$) conditions for 30 days were periodically analyzed by combined solvent-assisted flavor evaporation-gas chromatography-mass spectrometry (SAFE-GC-MS). The concentrations of most of the volatile components, including aldehydes, ketones, alcohols, acids, nitrogen- and sulfur-containing compounds, alkylfurans, furan derivatives and phenolic compounds, were affected to a greater extent by thermal storage compared with refrigerated storage. Profound increases in some volatile compounds with low odor detection thresholds, such as hexanal, octanal, (E)-2-octenal, (E,E)-2,4-decadienal, 1-octen-3-ol, 3-ethyl-2,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, 2-pentylfuran, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, dimethyl trisulfide, guaiacol, 4-vinylguaiacol and 4-vinylphenol, were observed in thermal stored soymilk. The volatile profile changes caused by thermal storage may influence the aroma quality of thermal-stored aseptic soymilk.

The effect of subjective perception and attitude of oral health on the oral health impact profile in industrial accident injury patients (산재환자의 주관적 구강건강상태와 보건태도가 구강건강 영향지수(OHIP)에 미치는 영향)

  • Lee, Hea Shoon;Lee, Kyung Hee
    • Journal of Korean society of Dental Hygiene
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    • v.14 no.5
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    • pp.757-764
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    • 2014
  • Objectives : The purpose of this study was to investigate the oral health impact profile (OHIP) in the industrial accident injury patients, and the effect of subjective perception and attitude of oral health on the oral health-related quality of life in industrial injury patients. Methods : A self-reported questionnaire was filled out by 496 industrial accident injury patients from October 29 to November 30, 2013. Data were analyzed using SPSS ver 20.0 program for chi-square test, t-test, ANOVA, Scheffe test, and Pearson's correlation coefficient. Results : The OHIP-14 was higher oral health-related quality of life in young people, women, highly educated persons, and those having high income and frequent scaling service. The subjective perception and attitude of oral health was closely correlated to the OHIP-14. The factors influencing on the oral health-related quality of life were the subjective perception and attitude toward oral health. Conclusions : It is necessary to emphasize the oral health promotion program for industrial injury patients. The government should pay more attention to the policy for the improvement of the oral health of industrial accident injury patients in the future.

Numerical studies on cavitation behavior in impeller of centrifugal pump with different blade profiles

  • Song, Pengfei;Zhang, Yongxue;Xu, Cong;Zhou, Xin;Zhang, Jinya
    • International Journal of Fluid Machinery and Systems
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    • v.8 no.2
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    • pp.94-101
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    • 2015
  • To investigate the influence of blade profiles on cavitation behavior in impeller of centrifugal pump, a centrifugal pump with five different blade profiles impellers are studied numerically. The impellers with five different blade profiles (single arc, double arcs, triple arcs, logarithmic spiral and linear-variable angle spiral) were designed by the in-house hydraulic design code using geometric parameters of IS 150-125-125 centrifugal pump. The experiments of the centrifugal pump have been conducted to verify numerical simulation model. The numerical results show that the blade profile lines has a weak effect on cavitation inception near blade inlet edge position, however it has the key effect on the development of sheet cavitation in impeller, and also influences the distribution of sheet cavitation in impeller channels. A slight changing of blade setting angle will induce significant difference of cavitation in impeller. The sharp changing of impeller blade setting angle causes obvious cavitation region separation near the impeller inlet close to blade suction surface and much more flow loss. The centrifugal pump with blade profile of setting angle gently changing (logarithmic spiral) has the super cavitation performance, which means smaller critical cavitation number and lower vapor cavity volume fraction at the same conditions.

FORMATION OF LINE PROFILES BY THE WINDS OF EARLY TYPE STARS

  • KANG IVIIN-YOUNG;KIM KYUNG-MEE;CHOE SEUNG-URN
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.263-264
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    • 1996
  • We have solved the radiative transfer problem using a Sobolev approximation with an escape probability method in case of the supersonic expansion of a stellar envelope to an ambient medium. The radiation from the expanding envelope turns out to produce a P-Cygni type profile. In order to investigate the morphology of the theoretical P-Cygni type profile, we have treated $V{\infty},\;V_{sto},\;{\beta}$ (parameter for the velocity field), M and $\epsilon$ (parameter for collisional effect) as model parametrs. We have found that the velocity field and the mass loss rate affect the shapes of the P-Cygni type profiles most effectively. The secondarily important factors are $V{\infty},\;V_{sto}$. The collisional effect tends to make the total flux increase but not so .much in magnitude. We have infered some physical parameters of 68 Cyg, HD24912, and $\xi$ persei such as V$\infty$, M from the model calculation, which shows a good agreement with the observational results.

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