• Title/Summary/Keyword: Upward and downward

Search Result 527, Processing Time 0.026 seconds

Directional Properties of 4 Type Constitution in Sasang Constitutional Medicine (사상의학에서 각 체질별 기운의 방향 특성)

  • Kim, Kwang-Hyeon
    • Journal of Sasang Constitutional Medicine
    • /
    • v.21 no.1
    • /
    • pp.53-62
    • /
    • 2009
  • 1. Objectives The purpose of this study is to find the ground why constitution must be classified into 4 types. 2. Methods I analysed the basic presuppositions to class 4 Type Constitution in Sasang Constitutional Medicine(SCM). And I connected the presuppositions with other theories from the viewpoint of directional properties of human body. 3. Results and Conclusions The most important presupposition to class 4 Type Constitution and apply to clinical therapy in SCM is that there is native strength and weakness of lung's Exhale Dispersing Qi, liver's Inhale Gathering Qi, spleen's Ascending Yin Qi and kidney's Descending Yang Qi. If there is superior tendency of Qi flow direction in human body, 6 directions(upward, downward, forward, backward, outward and inward) will be remarkable. But, in embryonic period, the outer skin is originated from the back(ectoderm) and the alimentary canal is from the front(endoderm). Therefore 4 directions(upward, downward, outward and inward) will be more remarkable, and those directions are included in the former presupposition.

  • PDF

Critical Heat Flux and Flow Pattern for Water Flow in Annular Geometry

  • Park, Jae-Wook;Baek, Won-Pil;Chang, Soon-Heung
    • Proceedings of the Korean Nuclear Society Conference
    • /
    • 1996.11a
    • /
    • pp.224-229
    • /
    • 1996
  • An experimental study on critical heat flux (CHF) and two-phase flow visualization has been performed for water flow in internally-heated, vertical, concentric annuli under near atmospheric pressure. Tests have been done under stable forced- circulation, upward and downward flow conditions with three test sections of relatively large gap widths (heated length = 0.6 m. inner diameter = 19 mm, outer diameter = 29, 35 and 51 mm). The outer wall of the test section was made up of the transparent Pyrex tube to allow the observation of flow patterns near the CHF occurrence. The CHF mechanism was changed in the order of flooding, chum-to-annular flow transition, and local dryout under a large bubble in churn flow as the flow rate was increased from zero to higher values. Observed parametric trends are consistent with the previous understanding except that the CHF for downward flow is considerably lower than that for upward flow.

  • PDF

Connected-component Labeling using Contour Following (윤곽추적 영역채색 기법)

  • 심재창;이준재;하영호
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.31B no.5
    • /
    • pp.95-107
    • /
    • 1994
  • A new efficient contour following algorithm for connected-component labeling processing is proposed. The basic idea of the algorithm is that the total number of downward chain codes is the same as one of upward chain codes along the closed contour. If the chain code direction is upward, then region start mark is assigned at the chain code departure pixel and if the chain code is downward, then region end mark is assigned at the chain code arrival pixel. The proposed algorithm extracts directly the contour information from only the current direction information of chain. This makes the algorithm simple and fast and requires less memory with comparison to the conventional algorithms.The proposed contour following algorithm can be applied to the various kind of image processing such as region filling, restoration and region feature extraction.

  • PDF

Investigation of Biases for Variance Components on Multiple Traits with Varying Number of Categories in Threshold Models Using Bayesian Inferences

  • Lee, D.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.7
    • /
    • pp.925-931
    • /
    • 2002
  • Gibbs sampling algorithms were implemented to the multi-trait threshold animal models with any combinations of multiple binary, ordered categorical, and linear traits and investigate the amount of bias on these models with two kinds of parameterization and algorithms for generating underlying liabilities. Statistical models which included additive genetic and residual effects as random and contemporary group effects as fixed were considered on the models using simulated data. The fully conditional posterior means of heritabilities and genetic (residual) correlations were calculated from 1,000 samples retained every 10th samples after 15,000 samples discarded as "burn-in" period. Under the models considered, several combinations of three traits with binary, multiple ordered categories, and continuous were analyzed. Five replicates were carried out. Estimates for heritabilities and genetic (residual) correlations as the posterior means were unbiased when underlying liabilities for a categorical trait were generated given by underlying liabilities of the other traits and threshold estimates were rescaled. Otherwise, when parameterizing threshold of zero and residual variance of one for binary traits, heritability estimates were inflated 7-10% upward. Genetic correlation estimates were biased upward if positively correlated and downward if negatively correlated when underling liabilities were generated without accounting for correlated traits on prior information. Residual correlation estimates were, consequently, much biased downward if positively correlated and upward if negatively correlated in that case. The more categorical trait had categories, the better mixing rate was shown.

Numerical Experiment on Migration using 45° Wave Equation (45°파동 방정식을 이용한 마이그레이숀 실험)

  • Jang, Hyuk-Jun;Yang, Sung-Jin;Shin, Chang-Soo
    • Economic and Environmental Geology
    • /
    • v.23 no.3
    • /
    • pp.353-358
    • /
    • 1990
  • This paper presents numerical experiments on migration of synthetic seismograms using by $45^{\circ}$ wave equation. The seismograms used are zero-offset seismogram (corresponding to stacked section) on point reflectors, dipping plane reflector, faulted and folded layers. The seismograms are constructed by upward continuation of seismic source wavelets, exploading on subsurface reflection interfaces, to the earth surface. The synthetic seismograms are migrated by downward continuation and imaging. The upward and downward continuations are implemented by solving the $45^{\circ}$ wave equation with the finite-difference method. Migration of the synthetic data used in this study results in relatively accurate reposition of subsurface structures while the synthetic sections are quite different from the structures.

  • PDF

Direct Numerical Simulation of Turbulent Mixed Convection in Heated Vertical Annulus (수직 동심 환형관 내의 난류혼합대류 현상에 관한 직접수치모사)

  • Jun, Yong-Joon;Bae, Joong-Hun;Yoo, Jung-Yul
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.33 no.9
    • /
    • pp.674-681
    • /
    • 2009
  • Turbulent mixed convection in heated vertical annulus is investigated using Direct Numerical Simulation (DNS) technique. The objective of this study is to find out the effect of buoyancy on turbulent mixed convection in heated vertical annulus. Downward and upward flows with bulk Reynolds number 8500, based on hydraulic diameter and mean velocity, have been simulated to investigate turbulent mixed convection by gradually increasing the effect of buoyancy. With increased heat flux, heat transfer coefficient first decreases and then increases in the upward flow due to the effect of buoyancy, but it gradually increases in downward flow. The mean velocity and temperature profiles can not be explained by the wall log laws due to the effect of buoyancy, too. All simulation results are in good quantitative agreement with existing numerical results and in good qualitative agreement with existing experimental results.

Direct numerical simulation of turbulent mixed convection in heated vertical annulus (수직 동심 환형관 내의 난류혼합대류 현상에 관한 직접수치모사)

  • Jun, Yong-Joon;Bae, Joong-Hun;Yoo, Jung-Yul
    • Proceedings of the KSME Conference
    • /
    • 2008.11b
    • /
    • pp.2759-2764
    • /
    • 2008
  • Turbulent mixed convection in heated vertical annulus is investigated using Direct Numerical Simulation (DNS) technique. The objective of this study is to find out the effect of buoyancy on turbulent mixed convection in heated vertical annulus. Downward and upward flows with bulk Reynolds number 8500, based on hydraulic diameter and mean velocity, have been simulated to investigate turbulent mixed convection by gradually increasing the effect of buoyancy. With increased heat flux, heat transfer coefficient first decreases and then increases in the upward flow due to the effect of buoyancy, but it gradually increases in downward flow. The mean velocity and temperature profiles can not be explained by the wall log laws due to the effect of buoyancy, too. All simulation results are in good quantitative agreement with existing numerical results and in good qualitative agreement with existing experimental results.

  • PDF

Effect of bidirectional internal flow on fluid.structure interaction dynamics of conveying marine riser model subject to shear current

  • Chen, Zheng-Shou;Kim, Wu-Joan
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.4 no.1
    • /
    • pp.57-70
    • /
    • 2012
  • This article presents a numerical investigation concerning the effect of two kinds of axially progressing internal flows (namely, upward and downward) on fluid.structure interaction (FSI) dynamics about a marine riser model which is subject to external shear current. The CAE technology behind the current research is a proposed FSI solution, which combines structural analysis software with CFD technology together. Efficiency validation for the CFD software was carried out first. It has been proved that the result from numerical simulations agrees well with the observation from relating model test cases in which the fluidity of internal flow is ignorable. After verifying the numerical code accuracy, simulations are conducted to study the vibration response that attributes to the internal progressive flow. It is found that the existence of internal flow does play an important role in determining the vibration mode (/dominant frequency) and the magnitude of instantaneous vibration amplitude. Since asymmetric curvature along the riser span emerges in the case of external shear current, the centrifugal and Coriolis accelerations owing to up- and downward internal progressive flows play different roles in determining the fluid.structure interaction response. The discrepancy between them becomes distinct, when the velocity ratio of internal flow against external shear current is relatively high.

An experimental investigation of natural convection heat transfer from fin arrays on a horizontal flat plate (水平平板에 附着된 핀配列에서의 自然對流 熱傳達에 관한 實驗的 硏究)

  • 오원균;조진호;권순석
    • Journal of the korean Society of Automotive Engineers
    • /
    • v.10 no.1
    • /
    • pp.26-32
    • /
    • 1988
  • A study has been conducted experimentally on the natural convection heat transfer characteristics of fin arrays on a horizontal flat plate in air. The effects of fin heights and Rayleigh numbers are mainly investigated. The experimental results are as follows; 1. The mean fin and mean total Nusselt numbers increase as dimensionless fin heights increase at 0.67.leg.H/s.leg.1.67. The mean plate Nusselt numbers increase in case of upward facing fins, but they decrease in case of downward facing fins. 2. The mean Nusselt numbers increase as Rayleigh numbers increase. 3. The mean fin surface Nusselt numbers has its maximum outside surface (Y$_{1}$) where there is no interference from each other fin. 4. The mean total Nusselt numbers in case of upward facing fins increase by 47% and 26%, respectively at H/S=0.67 and 1.67 than those in case of downward facing fins for Ra$_{s}$=6.50*10$^{3}$.>.

  • PDF

Cutting force prediction in the ball-end milling process of barious cutting area using Z-map (Z map을 이용한 임의의 절삭영역에서 볼엔드밀의 절삭력예측)

  • 김규만;조필주;김병희;주종남
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.14 no.3
    • /
    • pp.57-65
    • /
    • 1997
  • In this study, a cutting force in the Ball-end milling process is calculated using Z-map. Z-map can describe any type of cutting area resulting from the previous cutting geometry and cutting condition. Cutting edge of a ball-end mill is divided into infinitesimal cutting edge elements and the position of the ele- ment is projected to the cutter plane normal to the Z axis. Also the cutting area in the cutter plane is obtained by using the Z-map. Comparing this projected position with cutting area, it can be determined whether it engages in the cutting. The cutting force can be calculated by numerical integration of cutting force acting on the engaged cutting edge elements. A series of experiments such as contouring and upward/downward ramp cutting was performed to verify the calculated cutting force.

  • PDF