• Journal of the Korean housing association
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• v.4 no.2
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• pp.1-9
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• 1993

This study is a basic research to analyze and estimate the light environment of the classroom by serial correlation of time. Its purpose lies in the comparison by time period in order In select floor for laboratory and to calculate the uniformity factor. The proving ground is T building in W university, Which is five floor of central hall type. The subject of investigating is eight classrooms, four rooms in South and North, from the second floor that is net influenced by the shelter. The results that compared and estimated them in the illumination of daylight, Uniformity factor, Daylight factor, are as follows1. The illumination of classroom in South and North is over 10001x, but the classroom in North is good and the classroom in South excellent.2. The uniformity factor of classroom in South is good and that of classroom in North is normal.3. The daylight factor of each classroom is over 5% but the classroom in South is above that in North. The classroom in South surpasses the classroom in North in the general light environment and the classroom in third and fourth floor is so better than that in second and fifth floor in the condition of laboratory In the uniformity factor, the classroom in fourth can be better than any classroom.

• Journal of ILASS-Korea
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• v.24 no.3
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• pp.122-129
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• 2019

Flow uniformity in aftertreatment system is an important factor in determining uniform catalytic reaction and filtration. In this study, variety types of DOC-DPF system design were analyzed to increase flow uniformity. For this analysis, ANSYS Fluent was used with porous media setup for DOC and DPF. Turbulent flow was modeled by standard $k-{\varepsilon}$ model excepting porous media. Uniformity index was utilized to evaluate the flow uniformity quantitatively. Reference design showed low velocity region because two large vortex were generated before baffle. When radius of DOC-DPF system was increased, exhaust pressure acting on the inlet decreases and velocity distribution was shifted to one side. When inlet pipe was set to axial center of DOC-DPF system velocity distribution was symmetric. However, flow was not dissipated until the front end of DOC and showed higher uniformity index. When the volume of DOC was reduced while fixed volume of entire DOC-DPF system and baffle plate is located downstream of the DOC-DPF system, there was improvement in uniformity index.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1685-1688
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• 2004

I propose a modeling of a mechanism for weight fire uniformity measurement of a tire and a way I interpret a Sampling signal by Loadcell through an analysis, and to measure fire uniformity in this study. Correct a weight fire uniformity measurement was possible through the production of conversion and influence factor of a signal with a basis with the model who was an oscillation mechanics enemy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.2
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• pp.93-98
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• 2008

We investigated the effect of process temperature on removal rate and non-uniformity based on single head kinematics in oxide CMP. Generally, it has been known that the temperature profile directly transfers to the non~uniformity of removal rate on the wafer, which has similar tendency with the sliding distance of wafer. Experimental results show that platen velocity is a dominant factor in removal rate as well as average temperature. However, the non-uniformity does not coincide between process temperature and removal rate, due to slurry accumulation and low deviation of temperature. Resultantly, the removal rate is strongly dependent on the rotational speed of platen, and its non -uniformity is controlled by the rotational speed of polishing head. It means lower WIWNU (With-in-wafer-non-uniformity) can be achieved in the region of higher head speed.

• Journal of the Korean housing association
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• v.7 no.1
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• pp.105-116
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• 1996

The purpose of this study is to improve the quality of the light environment of classroom. To attain this purpose, this study estimated the physical factor and evaluation of the subjective response of classroon located in south and north in the summer and the winter. The results are as followed. 1. The evaluation of the illumination, uniformity factor, daylight factor as physical factor of light environment is good as classroom, but the classroom in south is better that that in north, the light environment in summer is better than winter. 2. The subjective response to light environment of classroom is positive on both seasons at all calssroom. Comparing summer with winter, I found that the difference of subjective response between both classrooms on summer is attentive. 3. The realtion between subjective response and physical factor of light environment in classroom is attentive on the light sense, content sense, uniformity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.9
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• pp.1652-1657
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• 2010

This paper analyzes optimal stirrer parameter to improve field uniformity in a mode-stirred reverberation chamber. Stirrer parameter is varied about stirrer height and stirrer angle. Also we analyze quality factor, number of excited modes and stirrer efficiency that affect field uniformity. The results show good performance as higher as stirrer height. Isotropic field distribution is formed at $45^{\circ}$ stirrer angle. When stirrer angle varies, scattering characteristic of incident wave are changed. So electric field distribution in a mode-stirred reverberation chamber is also changed. Therefore, it affect field uniformity. The results expect to help that designs stirrer for get better field uniformity. Immunity test performed designed mode-stirred reverberation chamber for semiconductor that categorized by technology. Test result shows that good recurrence compared wave-guide immunity test.

• Journal of the Semiconductor & Display Technology
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• v.3 no.3
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• pp.41-44
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• 2004

The aim of this study is the confirmation of the coating uniformity affected by the surface tension and wall attachment angle in a slit-coater model. In this work, we use the commercial code (Fluent) to solve the two-phase flow formed with air and photo resist numerically. The results show that the surface tension is the most important factor to determine the coating efficiency in the view of coating uniformity, and the coating uniformity is 2% for our slit-coater model and conditions. To improve the coating uniformity, it is in need of minimization of the sidewall effect of slit-coater.

• Journal of Korea Multimedia Society
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• v.12 no.7
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• pp.1016-1021
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• 2009

Among many factors for evaluating the performance of color printers, the color uniformity is an important factor during the stage of development and mass production. Currently the color uniformity is measured manually using densitometers and the data is analyzed by inspectors to evaluate the performance. In this paper a new method of estimating the color uniformity using scanners and average brightness is presented. The color uniformity of printouts is estimated by using the test pattern and commercially available scanner. It is shown from experiments that the estimated data are similar to the data measured by densitometers. Also, with the analysis of the color uniformity, the usefulness of the proposed approach is presented.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.4
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• pp.394-399
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• 2015

Because flow uniformity affects the life cycle and performance of the catalyst, it is an important design factor for selective catalytic reduction (SCR) systems. We examined how the diffuser angle and the area ratio of the inlet of the SCR reactor to the front of the catalyst affect flow uniformity. For the numerical analysis, we used STAR-CCM+, a common CFD software program. Analysis results showed that the larger the area ratio was, the less the flow uniformity was, and that the longer the diffuser length was, the greater the flow uniformity was. When the area ratio was greater than 1:5, the flow uniformity appeared very similar at the front of the catalyst. As a result, the spread time of the exhaust gas increased and the flow velocity decreased.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.6
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• pp.878-883
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• 2011

Effect of flow uniformity on the reaction characteristics of a catalytic combustor for high temperature fuel cell system has been experimentally investigated in the present study. One of the most important factor in designing catalytic combustion is to avoid hot spot in catalysts. In this regard, it is very important to secure flow uniformity of combustor inlet. A couple of perforated plates were applied at the front of catalyst region as flow uniformity device with minimal pressure drop. Results show that the velocity and temperature profile became more uniform when applying the flow uniformity device. CO and $CH_4$ emissions at the combustor exit were decreased and the average exit temperature was slightly increased with the flow uniformity device.