• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.4
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• pp.219-224
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• 2010

Recycling issue for the construction wastes is gradually important to future society. Recently, a star screen has been developed to use for this purpose, however some modifications were needed to enhance the separation accuracy. The objective of study is to evaluate and predict separation ability by verifying the effect for the modified shapes of the screen part. Two analysis models of the screen part were established using commercial software ADAMS to simulate the dynamic interaction of waste particles. Results showed that spacer and gear shapes directly affected separation ability. The modified spacer shapes were much higher screening rate with comparison to default shape. Screening ability for the half number of gear type was greater than other types. Therefore, modification of the design of screen part will be required to achieve better separation ability.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.5
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• pp.629-635
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• 2014

This paper describes propagation characteristics obtained by considering semiconducting screen and cross-bonding in underground transmission cables. The semiconducting screen of power cable has effect on propagation characteristics including attenuation, velocity and surge impedance. However, it is very difficult to apply the semiconduction screen for EMTP model because of the number of conductors limitation. Therefore, CIGRE WG 21-05 proposed advanced insulation structure and analysis technique of simplified approach including inner and outer semiconducting screen. In this paper, the various propagation characteristics analyse using this structure and technique for 154kV XLPE $2000mm^2$ cable. The frequency independent model of EMTP CABLE PARAMETER is used for just pattern analysis of propagation characteristics. For exact data analysis, the frequency dependent model of J-marti is used for EMTP modeling. From these result, various propagation characteristics of 154kV XLPE $2000mm^2$ cable according to semi conducting screen consideration, frequency range, cable length and pulse width are analysed. In addition, in this paper, the effects of cross-bonding are also variously discussed according to cross-bonding methods, direct connection and impedance of lead cable.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.15 no.3
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• pp.273-282
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• 1986

The purpose of this research was to study the characteristics of heat transfer in Heat Pipe which used the composition wick of screened groove - metallic mesh by ADI method and experimental results. As the results, the more than number of metallic mesh screen layers in a heat pipe increased, the fewer the effect of heat recovery decreased. In case of 1 - layer metallic mesh screen wick, the response of the effect in heat recovery was more rapidly showed than in case of other layers and in spite of high load, the evaporation section of Heat pipe with 1 - layer metallic mesh screen wick showed the stable response and did not show excessive super heat. There was a interrelation between thermal resistance and the variable layers, between thermal resistance and the variable gaps of metallic meshes, the heat transfer characteristics of Heat pipe were depended on the thermal resistance of composition wick.

• Resources Recycling
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• v.31 no.6
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• pp.36-43
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• 2022

The general screen used to separate the particle size of recycled aggregate has restrictions when dealing with moisturized materials because of the blockage phenomenon. Therefore, in this study, to improve the separation efficiency of the conventional screen, the excellence of additional vibrating device based on spring was decided by a simulation experiment based on the discrete element method (DEM). The motion characteristic was investigated by analyzing the displacement, amplitude, and strain angle based on the spring design. Further, the particle motion was simulated by applying spring motion. The material flow and separation efficiency of the screen applied spring were confirmed as 9.2 kg/s and 97 %, respectively. Consequently, the improvement in the screen applied with blockage prevention spring was confirmed by comparing with the conventional screen.

• Journal of Korea Multimedia Society
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• v.25 no.8
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• pp.1156-1166
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• 2022

In this study, we examined voice shopping interaction in which consumers can be involved in the decision-making process. Sixteen kinds of voice shopping interaction were designed with differences in the existence of screen/product involvement/conversation style. Their effects on trust, cognitive load, satisfaction, and continuous intention to use were evaluated through a survey experiment. The main effect of conversation style was significant, and it was found that the more deeply involved users have higher trust. The interaction effect between conversation style and product involvement was also significant. Low involvement product buyers had the most positive user experience from the conversation style that included 'Ask for preference,' while high involvement product buyers had the most positive user experience from the conversation style that included both 'Ask for preference' and 'Question and Answer.' The main effect and interaction effect of the existence of screen was not significant. The results indicate that a positive user experience can be obtained when users are deeply involved in consumer decision-making, especially in purchasing high-involvement products.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.4
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• pp.58-64
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• 2020

Large-scale flooding due to extreme weather and typhoons causes heavy damage. This is especially true in urban areas where accumulated debris prevents the smooth drainage of rainwater in sewage facilities such as rain gutters installed near roads. In this study, to improve the drainage performance and effectively remove foreign substances by applying the dust screen used in rivers, the rain gutter with Coanda effect was simulated and compared with the experiment. The simulation was performed by setting the parameters to the fillet radius R₁ and R₂ at the top of the screen filter, the fillet radius R₃ at the bottom of the screen filter, and the height H of the gap W from the bottom. W is the gap at the backside of screen filter which is applied to stimulate the Coanda effect. According to the simulation results, the highest drain performance was 87.99% derived from R₁= 30mm, R₂= 5mm, R₃= 85mm, H= 75mm, and W= 2mm. The error rate of simulation results refer to the 4.89%~7.36% compared to the experimental results. In the future, by considering the slope according to the installation environment, the simulation results can be applied to the actual roadside to help prevent flood damage.

• Journal of Power System Engineering
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• v.19 no.1
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• pp.83-89
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• 2015

A ball strainer screen module, which is used for a condenser tube cleaning system, is a critical mechanical component for maintaining condenser cleanliness. Despite of this importance, not many research have been focused on this module because of its relatively low usage. Employing CFD, this study examines the implication of fluid velocity change and blockage ratio on the ball strainer screen velocity and the static pressure distribution. Through this study, the impact of blockage in the space between ball strainer screen modules is verified. Also, it is found that the ranges of non-dimensional velocity distribution and static pressure distribution decrease as blockage ratio becomes smaller.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.829-837
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• 2001

Using Video Display Terminals(VDT) in the working environment often causes health complaints in the neck and shoulder region. This study was conducted on ten subjects, in order to investigate the change of electromyographic activities in the neck region(sternocleidomastoid muscle, upper trapezius muscle and erector muscle of cervical spine)with regards to the screen height and document holder position. A total of six different conditions of screen height and document holder position were measured during subjects performed a text-entry task for a duration of 10min. The raw EMG signal was transmuted into the root mean square(RMS). Two-way ANOVA for repeated measures was used to analyse the effects of the two factors. As a result, changing the screen height and document holder position has no effect on electromyographic activities in the neck region.

• Journal of Korea Multimedia Society
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• v.20 no.11
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• pp.1803-1810
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• 2017

A large amount of processing time is required if the process of detecting the touch position on the touch screen and displaying it on the display panel is performed only by software. In this paper, we propose a method to output information touched on the screen using H/W method in order to improve the response speed delay. In the FPGA module designed for the HDMI signal output to the display module, the touch information is input to the serial data signal including touch coordinate information, point size, and color information. Then the module render the image using HDMI signal input to the module and the touch information. This method has a pipeline structure so it has effect of reducing the delay time that occurs in outputting the touch information compared with the conventional software processing method.

• Journal of the Korean Graphic Arts Communication Society
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• v.20 no.2
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• pp.19-30
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• 2002

Four screen mesh counts of 100, 150, 200, and 305 threads per inch are chosen and a designed test figure is exposed on them for printing experiment to measure the ink deposit thickness. Among a number of variables, the ink viscosity, the screen gap and the squeegee pressure and speed are estimated with their effected thickness. These variables affect as much as around 50% compared with the theoretical ink volume listed by the mesh manufacturer and each variable has different influence on the thickness. The data and graphs have been analyzed for the thick film production.