• Solar Energy
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• v.18 no.3
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• pp.217-228
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• 1998

The purpose of this research is to investigate the characteristics of static and total pressure distribution in the upward free water jet system impinged on a downward flat plate. The rectangular nozzle was used and its contraction and aspect ratio was five and about seven respectively. Experimental conditions considered were jet velocity, distance between nozzle and flat plate, height of supplementary water. It was founded that pressure distribution on the flat plate had the Gaussian curve when the pressure at stagnation point and impinging half width were chosen as the scaling parameters. The maximum pressure was shown at the stagnation point. The central impingement velocity decreased with the increment of distance between nozzle and flat plate, and its slop of decay was similar to that of chracteristics decay region in the three-dimensional free jet.

• Korean Journal of Social Welfare
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• v.59 no.4
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• pp.273-296
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• 2007

In this Study, to reconstruct the disability identity scale(Lee and Shin, 2006)), Rasch rating scale model was applied to the four sub-dimensions of the Disability Identity Scale in a sample of spinal cord injuries(N=397). The Disability Identity Scale was verified by explorative factor analysis and confirmatory factor analysis. However, factor analytic procedures can't evaluate item-fit indices, item difficulty, and appropriate scale category. A number of limitations posed by confirmatory factor analytic procedures can be averted with the use of Rasch rating scale model which is in the item response theory(IRT). So in this study, Rasch model was applied to the Disability Identity Scale. Results revealed that (A) 20 items were selected from Rasch model, (B) the difficulty level of the Disability Identity Scale was the average level, (C) 4-point rating scale was appropriate for the Disability Identity Scale. Finally, we could suggest that the sub-dimensions concepts of the disability identity became clearer and items were to the good fitting.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.5
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• pp.691-697
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• 2008

Heat exchangers are commonly used in practice in a wide range of application, from heat and air-conditioning system in a household, to chemical processing and power production in large plant. An Experimental study was conducted to investigated the fluid flow and heat transfer around four circular cylinders of in-line in a cross flow of air. The local and average heat transfer characteristics for tube banks are investigated in the present study. Heat transfer in a heat exchanger usually involves convection in each fluid and conduction through the wall separating the two fluid. The in-line pitch ratio was in the range $1.5{\leq}L/d{\leq}4.0$, where L is the center distance and d the cylinder diameter, and in the Reynolds number $8,000{\leq}Re{\leq}50,000$. The local and mean Nusselt numbers were estimated. Subsequently, the heat transfer characteristics of four circular cylinders are found to exhibit a strong dependency upon the separation point of their upstream cylinders.

• Journal of Power System Engineering
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• v.12 no.5
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• pp.48-53
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• 2008

Heat exchangers are commonly used in practice in a wide range of application, from heating and air-conditioning system in a household, to chemical processing and power production in a large plant. Heat transfer in a heat exchanger usually involves convection in each fluid and conduction through the wall separating the two fluids. The heat transfer characteristics of tube banks of in-line arrangements of four circular cylinders in a cross flow are compared for a range of tube locations and Reynolds numbers. The in-line pitch ratio was set up in the range of $1.5\leq L/d\leq4.0$, where L is the center to center distance and d the circular cylinder diameter, and in the Reynolds number of $13,000\leq Re\leq50,000$. The local and mean Nusselt numbers were estimated, and then. Subsequently, the heat transfer characteristics of four circular cylinders were found to exhibit a strong dependency upon the cylinder spacing and separation point of their upstream cylinders.

• Journal of International Area Studies (JIAS)
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• v.14 no.1
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• pp.309-330
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• 2010

This paper examines the life-cycle and birth cohort effect on East Asian supranational identity. This paper also explores how national identity is related with supranational identity among Koreans. Using the 2008 CCGA-EAI survey, we analyze the determinants of supranational East Asian identity. The results suggest several interesting findings. Age and national identity have positive effects on East Asian identity. Among generational cohorts, the democratization cohort were less likely than other cohorts to have East Asian identity. These findings suggest several implications. First, in Korea, unlike other countries in the Western world, the older tend to have stronger regional identity than the younger do. Second, unlike the existing literature, this paper finds that strong national identity (pride) is complementary, rather than substitutive, to supranational regional identity. This warrants further systematic research on the microfoundation on the relationship between regional integration and nationalism in Northeast Asia.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.2
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• pp.262-270
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• 1987

A numerical method is presented which can solve the unsteady momentum and thermal boundary layers, coupled through the agency of buoyancy force, over a heated circular cylinder impulsively started from rest. By linearizing the nonlinear finite difference equations without sacrificing accuracy, numerical solutions are obtained at each time step without iteration. To get rid of the requirement of excessive number of grid points in the region of reversed flow, special form of transformed variables are used, by which the computational boundary layer thickness is maintained almost constant. These numerical properties enable the method to easily handle the region of reversed flow and how the singularity develops in the interior of the boundary layer. In order to investigated the thermal effects on the skin friction, heat flux, displacement thickness and on the separation, we have successfully solved three different cases of the buoyancy parameter .alpha.(Gr/Re$^{2}$).

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.497-508
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• 2014

The current study examined the relationships between task-approach skills of optimism, bearability, intolerance of uncertainty, career identity, career maturity, career barriers, and career aspiration. Data was collected from two-hundred sixty nine college students who matriculated in colleges located in Seoul, Gyeoungi and Chungchung provinces in Korea. The correlation analysis and multiple linear regression were carried out to explore the relationship among the variables mentioned above. The results of this study were as follows: First, career identity was positively correlated with career maturity, aspiration and negatively with career barrier. optimism was negatively correlated with career barrier. in addition, intolerance of uncertanity was positively correlated with career maturity. and negatively with career barriers. Second, multiple linear regression revealed that career identity, optimism and lacking intolerance of uncertanity significantly influenced career maturity, career identity, optimism and intolerance of uncertanity significantly influnced career barriers. In addition, only optimism influnced career aspiration. These findings implied that career counselors need to assist clients developing optimism, flexibility, bearability and counselors should be aware of the effect of task-approach skills on career, barriers, and aspiration. Further discussions regarding results are included.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.117-124
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• 2010

Most of the rivers which exist in nature are not a single river but the network that is composed of several branches and mainstreams. The river network are more complicated than other sigle rivers and streams. Therefore the hydraulic characteristics are sensitively changed by reduction and expansion of the width in the confluence or the variation of the flux. In this paper, the hydraulic characteristics were calculated by the change of the width and length in the confluence and the hydraulic model test. The deposit of confluence emerged at the left bank, right bank and the stagnation sector. As the total flow in the branch have increased, stagnation of the left bank and right bank have decreased. When the width of the downstream have been get smaller from 3 m to 2 m, the deposit of the left bank and right bank and stagnation sector have decreased. But as the eddy flow in the center of the confluence is occurred, the erosion has been increased. The result of this paper can be used as a basic data of water management around the junction and for maintenance on the ground of development of the river.

• Solar Energy
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• v.13 no.1
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• pp.1-10
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• 1993

The purpose of this research is to investigate the characteristics of heat transfer in the downward axisymmetric free water jet system impinged on a flat oblique plate which has the uniform heat flux. Experimental conditions considered were Reynolds number, distance between nozzle and Bat plate, inclination angle of heater surface and nozzle exit velocity. Local Nusselt number was subjected to the influence of Re number, Pr number, oblique angle of heating surface and local position of flat plate. In the wall region of downward surface, The secondary peak point of heat transfer appeared at the local point of X/D=-8 from the stagnation point. The stagnation heat transfer rate of this experimental study augments 2.4 times than that of laminar theorical solution. The stagnation nusselt number is function of Reynolds number, nozzle-plate spacing Prandtl number and oblique angle of impinging plate.

• 프린팅코리아
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• v.11 no.5
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• pp.132-135
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• 2012

현장개선은 인쇄회사에 있어서도 보편적인 테마가 되었다. 더욱이 오랫동안 정체 및 감소세를 보이고 있는 일본 인쇄업계의 사정을 감안하면, 개선활동을 통해 사고의 발생을 줄이고, 인쇄 사고를 미연에 방지하는 것은 그 중요성이 더욱 커지고 있다고 할 수 있다. 우선적으로는 사고가 발생하지 않는 생산체제를 확립하는 것이 이뤄져야 한다. 또한 현장 개선에 있어서 취약점으로 지적되고 있는 협력업체에서 이뤄지는 고정에 대한 관리까지도 염두에 둬야 한다.