• Title/Summary/Keyword: Body fluid

Search Result 1,313, Processing Time 0.027 seconds

The Effect of Surface Tension on the Transient Free-Surface Flow near the Intersection Point (교차점 부근의 과도자유표면유동에 미치는 표면장력의 영향)

  • Lee, G.J.;Rhee, K.P.
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.28 no.2
    • /
    • pp.104-117
    • /
    • 1991
  • When a body starts to move, the flow near the intersection point between a body and a free surface changes violently and rapidly in a very short initial time interval. This flow phenomena must be investigated whenever one treats the interaction between a body and a fluid, such as the motion of a floating body, sloshing in a tank, wave maker problem, entry of a body into a fluid etc.. Until Roberts(1987), it was widely accepted that a singularity exists at the intersection point. However, he showed that the singularity does not exist if a body moves non-impulsively. In this paper, an analytical solution cosistent for the case of impulsive motion of a body is obtained by including the effect of surface tension. From the characteristics of the newly obtained solution, a critical value associated with an oscillating phenomenon is found, and further more, it is shown that the oscillating phenomenon does not appear in the region where the distance form the intersection point is less than this critical value.

  • PDF

Thermal and Structural Analyses of Semi-metallic Gasket Joined with Graphite Seal for Ship Engine Piping Flange (선박엔진 배관 플랜지용 세미금속 가스켓의 열전달 및 구조해석)

  • Oh, Jeong-seok;Lee, In-sup;Yoon, Han-ki;Sung, Heung-kyoung
    • Journal of Ocean Engineering and Technology
    • /
    • v.31 no.5
    • /
    • pp.352-356
    • /
    • 2017
  • We performed thermal and structural analyses to evaluate the structural integrity of a semi-metal gasket for a flange with increases in the internal fluid temperature and pressure using a commercial FEA program. As a thermal analysis result, the temperature distribution of the gasket body increased with an increase in the internal fluid temperature until the maximum fluid temperature of $600^{\circ}C$. In addition, the structural analysis showed that contact pressures of more than 35 MPa occurred uniformly in the graphite seal regions. It was found that no fluid leakage occurred under the load conditions for the structural analysis because the contact pressure in the graphite seal region was greater than the maximum internal fluid pressure of 35 MPa. Therefore, we demonstrated the structural integrity of the semi-metal gasket by performing the thermal and structure analyses under the maximum fluid temperature of $600^{\circ}C$ and the internal fluid pressure of 35 MPa.

The Correlation Analysis of Fluid Intake, Skin Hydration and Skin pH of College Students (대학생의 수분섭취, 피부 수분보유도 및 피부 pH와의 관계)

  • Kim, Nam-Jo;Hong, Hae Sook
    • Journal of Korean Biological Nursing Science
    • /
    • v.17 no.2
    • /
    • pp.132-139
    • /
    • 2015
  • Purpose: The purpose of this study was to verify the correlation analysis between fluid intake on skin hydration and pH of college students. Methods: The subjects were 129 female nursing students in D city. Data were collected by a self-administered questionnaire, using a skin moisture checker and skin pH meter on faces, hands, and feet. The collected data were analyzed by descriptive statistics, t-test, ANOVA, and Pearson correlation analysis, using SPSS WIN, 20. Results: The daily fluid intake was composed of 57% pure water, 21% caffeinated beverages, 22% non-caffeinated beverages. There were significant differences in average skin hydration on the three body parts according to pure water, caffeinated beverages, and non-caffeinated beverages; however, there was no significant difference measured by fluid intake. There was a significant positive correlation between fluid intake and skin hydration: between pure water and skin hydration. There was significant negative correlation between caffeinated beverages and skin hydration: between non-caffeinated beverages and skin hydration. Conclusion: The results suggest that fluid intake, pure water, caffeinated beverages, and non-caffeinated beverages have an effect on skin hydration and pH. Therefore, it is good to increase the amount of fluid intake but, it is recommended to increase the amount of intake of pure water rather than beverages to improve skin status.

Study on the Recognition on Phlegm-retained fluid of Five Physicians in the Onbo School (온보학파(溫補學派) 5인(人)의 담음(痰飮) 인식에 대한 연구)

  • Kim, Jin Ho;Park, Hae Mo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.26 no.6
    • /
    • pp.864-868
    • /
    • 2012
  • This study aimed to examine the recognition on phlegm-retained fluid of the Onbo School's five physicians, Xue Ji(薛己), Sun Yi-kui(孫一奎), Zhao Xian-ke(趙獻可), Zhang Jie-bin(張介賓), and Li Zhong-zi(李中梓), who made important contributions in the formation of Tanbing theories. Five authors were included as the study subjects. The study examined on the definition, causes, classification, therapeutic methods, and instructions of phlegm-retained fluid. The results are Phlegm-retained fluid is formed when the normal circulation of body fluid is not functioning properly. Plegm (痰) is thick, slimy, and murky fluid. In contrast, retained fluid(飮) is clear and watery fluid. The major causal organs of phlegm-retained fluid formation were pointed out as pancreas and kidney. Five physicians had different opinions regarding the classification of phlegm-retained fluid. Warming and tonifing the spleen and stomach(溫補脾胃) and tonifing the kidney(補腎) were taken as the suitable methods for treating phlegm-retained fluid. The common characteristics of the Onbo School were verified in terms of formation and treatment methods for phlegm-retained fluid. However, specific common points were hardly found in other items. The Onbo School had varied opinions on the processing methods of Rehmannia glutinosa(熟地黃). Further discussion on related references are essential.

INORGANIC SELENIUM FOR SHEEP I. SELENIUM BALANCE AND SELENIUM LEVELS IN THE DIFFERENT RUMINAL FLUID FRACTIONS

  • Serra, A.B.;Nakamura, K.;Matsui, T.;Harumoto, T.;Fujihara, T.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.7 no.1
    • /
    • pp.83-89
    • /
    • 1994
  • The effects of inorganic selenium (Se), selenate and selenite on Se balance levels in the different ruminal fluid fractions were studied using Japanese Corriedale wethers with an average body weight of 47 kg. A $3{\times}3$ Latin square design was used with three animal, three periods and three treatments. In each period, there was 7 d dietary adjustment followed by 5 d total collection of urine and feces. Ruminal fluid samples were obtained at 0, 1, 3, 5 and 7 h postprandially on the final day of the collection period. The three dietary treatments were: (1) without Se supplementation (control); (2) with Se supplement as sodium selenate; and (3) sodium selenite at a rate of 0.2 mg Se/kg dietary DM. The basal diet was timothy hay (Phleum pratense L.) fed 2% of body weight/d. Results indicated that Se balance were higher (p < 0.05) for those animals under supplementation than those animals under control. Overall data gathered showed a similar digestion balance of selenate and selenite in sheep. Inorganic Se, both selenate and selenite produced positive Se contents of the ruminal feed particles and protozoa. Bacterial Se increased (p < 0.05) on the first three hours post-prandially in Se supplemented diets. Gross ruminal fluid fraction, although there was improvement on their Se content under the supplemented diets, the changes were insignificant over the control. free inorganic Se and Se in soluble protein of the ruminal fluid were not significantly different for selenate and selenite. Most of the Se in the ruminal fluids of the animals under supplementation were insoluble, indicating the influence of rumen environments on Se bioavaliability.

Surface Lay Effects on the Lubrication Characteristics in the Valve Part of a Swash-plate Type Axial Piston Pump (표면가공무늬가 사판식 액셜 피스톤펌프의 밸브부 윤활특성에 미치는 영향에 관한 연구)

  • Shin, Jung-Hun;Kang, Bo-Sik;Kim, Kyung-Woong
    • Tribology and Lubricants
    • /
    • v.28 no.1
    • /
    • pp.12-18
    • /
    • 2012
  • This application study of a swash-plate type axial piston pump was concerned about the lubrication characteristics between cylinder barrel and valve plate which are the main rotating body and its opposite sliding part respectively. A computer simulation was implemented to assess bearing and sealing functions of the fluid film between cylinder barrel and valve plate. A numerical algorithm was developed to facilitate simultaneous calculations of dynamic cylinder pressure, 3 degree-of-freedom barrel motions considering inertia effect, and fluid film pressure assuming full fluid film lubrication regime. Central clearance, tilt angle, and azimuth angle of the rotating body were calculated for each time step. Surface waviness was found to be an influential factor due to the small fluid film thickness which can appear in flat land bearings. Five surface lays which can form on the lubrication surface in accordance with machining process were defined and analyzed using the simulation tool. Oil leakage flow and frictional torque in the fluid film between cylinder barrel and valve plate were also calculated to discuss in the viewpoint of energy loss. The simulation results showed that in actual sliding conditions proper surface non-flatness can make a positive effect on the energy efficiency and reliability of the thrust bearing.

Fluid Inclusion Study of Sangdong Tungsten Deposits (상동(上東) 중석광상(重石鑛床)의 유체포유물(流體包有物) 연구(硏究))

  • Mun, Kun Joo
    • Economic and Environmental Geology
    • /
    • v.12 no.4
    • /
    • pp.197-206
    • /
    • 1979
  • Sangdong scheelite deposit is confirmed to have been formed by replacement of limestone beds by metasomatic mineralization. Mineralogical zonal distribution and filling temperatures are related with order of its formation and tungsten mineralization. The first formed garnet-pyroxene zone, left in the margins of the ore body, shows the highest filling temperature of fluid inclusions in pyroxene, averaging $420^{\circ}C$. The central part of the ore body, mainly composed of quartz-mica-scheelite, shows higher fi11ing temperatures of fluid inclusions in quartz, than hornblende-quartz-scheelite zone surrounding the quartz-mica-scheelite zone, averaging $240^{\circ}C$. The distribution of highter filling temperatures above average temperature is applicable to the richest part of scheelite distribution. Generally scheelite shows higher filling temperature by about 20 to $100^{\circ}C$ than quartz in a given sample. The crystallization temperature of the main phase of scheelite deposition is $311^{\circ}C$ at the pressure of 230 to 500 bars at Sangdong area. Gas-rich inclusions in the pyroxene are homogenized into either gas or liquid phase or into both phases in a given crystal of the pyroxene, which suggests boiling at the formation of skarn.

  • PDF

A Study on Naosuixiaoshuo in Huangdineijing (『황제내경(黃帝內經)』의 뇌수소삭(腦髓消爍)에 대한 소고(小考))

  • Kim, Beom-seok;Baik, You-sang
    • Journal of Korean Medical classics
    • /
    • v.31 no.1
    • /
    • pp.127-138
    • /
    • 2018
  • Objectives : The paper reviews the texts related to Naosuxiaoshuo in Huangdineijing, and investigates its cause, mechanism, prognosis and symptom expressions. Methods : The paper searches for the texts within Huangdineijing that deal with Naosuxiaoshuo, and tries to clarify the significance and the characteristics of Naosuxiaoshuo using the annotators comments regarding this issue. Moreover, the paper tries to search for similarities between the symptoms of Naosuxiaoshuo and the relevant diseases in modern medicine. Results : Naosuxiaoshuo is a serious disease where the diminishing of the brain's parenchyma can even lead to death. The cause is yin-deficiency based on the lack of vital essence and body fluid, and it also can be caused by the external pathogen or other stimulations. Moreover, it shows some similarities with brain atrophy and cerebrospinal fluid diseases. Conclusions : Naosuxiaoshuo should be treated with a focus on yin-tonifying dealing with spleen related to production of body fluid and the kidney related to storage of vital essence. It is also important to prevent external pathogens or stimulations damaging the bone marrow.

Structural Analysis on the Arm and Floater Structure of a Wave Energy Converter

  • Chen, Zhenmu;Singh, Patrick Mark;Choi, Young-Do
    • The KSFM Journal of Fluid Machinery
    • /
    • v.18 no.3
    • /
    • pp.5-11
    • /
    • 2015
  • Ocean waves have huge amounts of energy, even larger than wind or solar, which can be extracted by some mechanical device. This can be done by creating a system of reacting forces, in which two or more bodies move relative to each other, while at least one body interacts with the waves. This moves the floater up and down. The floaters are connected to an arm structure, which are mounted on a fixed hull structure. Hence, the structure of the floater is very important. A static structural analysis with FSI (Fluid-Structure Interaction) analysis is conducted. To achieve the pressure load for the FSI analysis, the floater is simulated on a wave generator using rigid body motion. The structural analysis is done to examine the stresses on the whole system, and four types of flange and floater are optimized. The result shows that the structure of floater with wood support is the safest.

A Case Study on Sintering Characteristics of Yttria Stabilized Zirconia Powder Prepared by Two-Fluid Spray Drying

  • Choi, Jin Sam;Kong, Young-Min
    • Journal of the Korean Ceramic Society
    • /
    • v.53 no.3
    • /
    • pp.332-337
    • /
    • 2016
  • As a case study on yttria stabilized zirconia ceramics, the sintering characteristics of submicron powders and the granulation prepared by two-fluid spray drying of submicron particles were investigated. As-received powders of yttria stabilized zirconia particles were reduced to a uniform size of less than about 200 nm by repeated milling. Granulation size obtained by the two-fluid spray drying was affected by the organic matter and the primary particle size. Sintering behavior such as porosity, water absorption ratio, density, and transparency was influenced by processing conditions of the powder, and the discontinuous interfaces in a green body were reduced.