• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.268-281
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• 2004

A study was carried out in order to estimate the deformation of the pound net according to the current by the model test in the circulating water channel. The tension of the frame rope and the variation of net shape were measured to investigate the deforming of the model pound net in the flow. The results are obtained as follows; 1. The experimental equation between tensions (R) of the frame rope and velocity (ν)was found to be R=$19.58v^{1.98}$($r^2$=0.98) in case of the upperward flow with fish court net and R=$26.90v^{1.72}$($r^2$=0.95)at the upperward flow with bag net according to the velocity from 0.0m/s to 0.6m/s, respectively. 2. As the variation of flow speed inside of the model net was gradually decreased according as which is passed through netting panels, in case of the upperward flow with fish court net, the flow speed was about 70% of initial flow speed at 0.1m/s, 60% at 0.2m/s, 50% at 0.3m/s and 40% 0.4~0.6m/s at the measurement point(h) inside of the first bag net, respectively. In case of the upperward flow with bag net, as the flow speed was steeply decreased according as which if passed through the second bag net, it was 30~60% of the initial flow speed and was 20~30% inside of the first bag net and was about 10~20% inside of the inclined passage net. 3. In case of the upperward flow with fish court net, the variation of deformed angle of fish court net was from 0$^{\circ}$ to 70$^{\circ}$and that of inclined passage net was from 0$^{\circ}$ to 63$^{\circ}$and that of the second bag net was from 0$^{\circ}$ to 47$^{\circ}$ . 4. In case of the upperward flow with fish court net, the variation of deformed angle of the second bag net was changed from 0$^{\circ}$ to 70$^{\circ}$and that of the inclined passage net was from 0$^{\circ}$ to 55$^{\circ}$ and that of the fish court net was from 0$^{\circ}$ to 50$^{\circ}$. The depth ratio of the first bag net was changed from 0% to 35% and that of the second bag net was from 0% to 20% and that of the inclined passage net was from 0% to 35%. In the flow speed 0.5m/s, the inclined passage net was raised up to the entry of the bag net and then prevented it more over 90%. 5. To be increased the opening volume of pound net, it needs to attach the added weight outside of the fish court net, inclined passage net and bag net. At the same time, it needs to adjust the tension of the twine for maintenance of the shape.

• Journal of Korean Academy of Nursing
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• v.27 no.3
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• pp.541-549
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• 1997

This study was done to describe health promoting lifestyle and determine affecting factors in elderly based on the Heath Promotion Model by Pender. Cognitive-perceptual factors that were included in this study were self-efficacy and hardiness. Modifying factors were demographic characteristics (sex, age, partner, previous illness, education level. income and religion). The specific purpose of this study was to examine the relationships of self-efficacy, hardiness and the demographic chasteristics to health promoting lifestyle and to determine causal factors affecting the elderly. The subjects were a volunteer sample of 98 elderly in one city in? The instruments for this study were Health Promoting Lifestyle Profile(47items, 4scale), Health Related Hardiness Scale(22i1ems, 6scale), general Self-Efficacy Scale(13i1ems, 5scale). Frequency, percentage, t-test, ANOVA, Pearson's correlation coefficient and Stepwise Multiple regression technique with SAS program were used to analyse the data. The Results of the study are as follows : 1) The average item score for the health promoting lifestyle was 2.63, the highest score on the subscales was interpersonal support (M=3.3), followed by self-actulization(M=2.9), nutrition(M=2.8), stress management(M=2.7), health responsibility(M=2.1) with the lowest bring exercise(M=2.0) 2) A significant difference between education level, income, religion and health promoting lifestyle were found. 3) All of the subscales on health promoting lifestyle were positively related to total hardiness (r=0.330, p<0.001). The hardiness subscale of control was positively related to self-actulization(r=0.276, p<0.01), and commitment was positively related to self-actualization(r=0.315, p<0.001), exercise /nutrition(r=0.245, p<0.01), interpersonal support(r=0.278, p<0.01), stress management(r=0.250, p<0.01). Challenge was positively related to self-actualization(r=0.315, p<0.001), exercise /nutrition(r=0.245, p<0.01). There was no significant correlation between self-efficacy and all of the subscales of health promoting lifestyle. Self-efficacy showed a significant correlation only with control(r=0.469, p<0.001), comittment(r=0.507, p<0.001), challenge (r=0.489, p< 0.001). 4) Comittment, self-efficacy and income explained 25.01% of the variance for the total health promoting lifestyle. The results of this study show that commitment, self efficacy and income predicted the health promoting lifestyle of the elderly. So health promoting programs that increase commitement and self-efficacy should be developed to promote a healthy lifestyle of the elderly, especially those who have low income.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.237-240
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• 2002

A CCFL model for high frequency dimming electronic ballast simulation is presented in this paper. The model can be utilized for an electronic ballast simulation with continuous dimming and transient mode simulation such as step dimming. The piezoelectric transformer Is evaluated using an AC analysis. The electronic ballast composed of piezoelectric transformers and ZVS inverter was implemented. It enables a fluorescent lamp to be fumed on stably. Simulation of a high frequency electronic ballast which operates a fluorescent Imp at high frequency is proposed. Simulation is carried out using PSPICE program to illustrate the performance of the circuit

• Journal of the Korean Solar Energy Society
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• v.22 no.2
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• pp.19-26
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• 2002

This study aims at numerically analyzing on heat transfer the characteristics and pressure drop of plate heat exchanger(PHE) using the Phoenics 3.1 VR Editor for the standard k-$\varepsilon$ model. Computations have been carried out for a range of chevron angle from $30^{\circ}$ to $60^{\circ}$, inlet velocity from 0.03m/s to 0.63m/s and the height of corrugation from 0.0045m to 0.0060m. The results show that both of heat transfer performance and pressure drop increase as chevron angle increases. This is because higher troughs produce higher turbulence and a higher heat transfer coefficient in the liquids flowing between the plates. As inlet velocity from 0.03m/s to 0.63m/s increases, heat transfer performance and pressure drop increase parabolically. As the height of corrugation increases, both of heat transfer performance and pressure drop decrease with the decrease of velocity. And the pressure drop decreases and the friction factor increases as the height of corrugation increases.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.4
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• pp.173-181
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• 2002

The sinoatrial (SA) node is a complex and inhomogeneous tissue in terms of cell morphology and electrical activity. There are two models of the cellular organisation of the sinoatrial node: the gradient and mosaic models. According to the gradient model there is a gradual transition in morphology and electrical properties of SA node cells from the centre to the periphery of the SA node. In the mosaic model, there is a variable mix of atrial and sinoatrial node cells from the centre to the periphery. This review focuses on the cellular organisation of the rabbit sinoatrial node in terms of the expression of connexin (Cx40, Cx43 and Cx45), L-type $Ca^{2+}$ channel and $Na^+-Ca^{2+}$ exchanger proteins. These immunocytochemical data, together with morphological and electrophysiological data, obtained from the intact sinoatrial node and isolated sinoatrial node cells support the gradient model of the cellular organisation of the SA node. The complex organisation of the sinoatrial node is important for the normal functioning of the sinoatrial node: (i) it allows the sinoatrial node to drive the surrounding hyperpolarized atrial muscle without being suppressed by it; (ii) it helps the pacemaker activity of the sinoatrial node continue under a wide range of physiological and pathophysiological conditions; (iii) it helps protect the sinoatrial node from reentrant arrhythmias.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.218-221
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• 1997

In this paper, we designed a myocaldial ischemia model based on L-R dynamic model including hyperkalemia and anoxia. Using the model, we simulated the effects of ionic concentration $[K^+]_o$ and intracellular $[ATP]_i$ on action potential in single cardiac cell. Also we evaluated this model by comparing the simulated results with that of other researches. In luther research, we are going to consider the effect of acidosis quantitatively.

• Communications for Statistical Applications and Methods
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• v.16 no.4
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• pp.605-614
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• 2009

TGARCH models characterized by asymmetric volatilities have been useful for analyzing various time series in financial econometrics. We are concerned with persistent volatility in the TGARCH context. Park et al. (2009) introduced I-TGARCH process exhibiting a certain persistency in volatility. This article applies I-TGARCH model to various financial time series in Korea and it is obtained that I-TGARCH provides a better fit than competing models.

• Transactions of Materials Processing
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• v.29 no.6
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• pp.356-361
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• 2020

In general, the drawing process is performed in a multi-pass to meet the required shape and cross section. In the drawn material, the surface strain is relatively higher than the center due to the direct contact with the die. Therefore, a non-uniform strain distribution appears in the surface of the material where the strain is concentrated and the center having a relatively low strain, thus it is difficult to predict the strain in the drawn material. In this study, the non-uniform strain distribution was evaluated using a finite element analysis and the non-uniform strain distribution model based on the upper bound method. In addition, the relationship between the hardness and the strain was established through a simple compression test to evaluate the distribution of the strain in the experimentally multi-pass drawn bar.

• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1444-1450
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• 2019

The fast-neutron shielding behaviour (FNSB) of two clay-materials (Ball clay and Kaolin)of Southwestern Nigeria ($7.49^{\circ}N$, $4.55^{\circ}E$) have been investigated using effective removal cross section, ${\Sigma}_R(cm^{-1})$, mass removal cross section, ${\Sigma}_{R/{\rho}}(cm^2g^{-1})$ and Mean free path, ${\lambda}$ (cm). These parameters decide neutron shielding behaviour of any material. A computer program - WinNC-Toolkit has been used for computation of these parameters. The toolkit evaluates these parameters by using elemental compositions and densities of samples. The proficiency of WinNC-Toolkit code was probe by using MCNPX and GEANT4 to model fast neutron transmission of the samples under narrow beam geometry, intending to represent the actual experimental setup. Direct calculation of effective removal cross section ($cm^{-1}$) of the samples was also carried out. The results from each of the methods for each types of the studied clay-materials (Ball clay and Kaolin) shows similar trend. The trend might be the fingerprint of water content retained in each of the samples being baked at different temperature. The compositions of each sample have been obtained by Particle-Induced X-ray Emission (PIXE) technique (Tandem Pelletron Accelerator: 1.7 MV, Model 5SDH). The FNSB of the selected clay-materials have been compared with standard concrete. The cognizance of various factors such as availability, thermo-chemical stability and water retaining ability by the clay-samples can be analyzed for efficacy of the material for their FNSB.

• Environmental Engineering Research
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• v.20 no.4
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• pp.347-355
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• 2015

The growth kinetics of phototrophic microorganisms can be controlled by the light irradiance, the concentration of an inorganic nutrient, or both. A multi-component kinetic model is proposed and tested in novel batch experiments that allow the kinetic parameters for each factor to be estimated independently. For the cyanobacterium Synechocystis sp. PCC6803, the estimated parameters are maximum specific growth rate $({\mu}_{max})=2.8/d$, half-maximum-rate light irradiance $(K_L)=11W/m^2$, half-inhibition-rate light irradiance $(K_{L,I})=39W/m^2$, and half-maximum-rate concentration for inorganic carbon $(K_{S,Ci})=0.5mgC/L$, half-maximum-rate concentration for inorganic nitrogen $(K_{S,Ni})=1.4mgN/L$, and half-maximum-rate concentration for inorganic phosphorus $(K_{S,Pi})=0.06mgP/L$. Compared to other phototrophs having ${\mu}max$ estimates, PCC6803 is a fast-growing r-strategist relying on reaction rate. Its half-maximum-rate and half-inhibition rate values identify the ranges of light irradiance and nutrient concentrations that PCC6803 needs to achieve a high specific growth rate to be a sustainable bioenergy source. To gain the advantages of its high maximum specific growth rate, PCC6803 needs to have moderate light illumination ($7-62W/m^2$ for ${\mu}_{syn}{\geq}1/d$) and relatively high nutrient concentrations: $N_i{\geq}2.3 mgN/L$, $P_i{\geq}0.1mgP/L$, and $C_i{\geq}1.0mgC/L$.