• Proceedings of the Korean Society of Rheology Conference
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• 2006.06a
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• pp.81-84
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• 2006

Slot coating process, in continuous and patch modes, has been applied for the many precise coating products, e.g., flat panel displays and second batteries. However, manufacturing uniform coating products is not a trivial task at high-speed operations because various flow instabilities or defects such as leaking, bubbles, ribbing, and rivulets are frequently observed in this process. It is no wonder, therefore, that many efforts to understand the various aspects of dynamics and coating windows of this process have been made both in academia and industry. In this study, as the first topic, flow dynamics within the coating bead in slot coating process has been investigated using the one-dimensional viscocapillary model by lubrication approximation and two-dimensional model by Flow-3D software. Especially, operability windows in both 1D and 2D cases with various slot die lip designs have been successfully portrayed. Also, effects of process conditions like viscosity and coating gap size on slot coating window have been analyzed. Also, some experiments to find minimum coating thickness and coating windows have been conducted using slot die coater implemented with flow visualization device, corroborating the numerical results. As the second topic, flow dynamics of both Newtonian and Non-Newtonian fluids in patch or pattern slot coating process, which is employed in manufacturing IT products such as secondary batteries, has been investigated for the purpose of optimal process designs. As a matter of fact, the flow control in this system is more difficult than in continuous case because od its transient or time-dependent nature. The internal die and die lip designs for patterned uniform coating products have been obtained by controlling flow behaviors of coating liquids issuing from slot. Numerical simulations have been performed using Fluent and Flow-3D packages. Flow behavior and pressure distribution inside the slot die has been compared with various die internal shapes and geometries. In the coating bead region, efforts to reduce irregular coating defects in head and tail parts of one patterned coating unit have been tried by changing die lip shapes. It has been concluded that optimal die internal design gas been developed, guaranteeing uniform velocity distribution of both Newtonian and shear thinning fluids at the die exit. And also optimal die lip design has been established, providing the longer uniform coating layer thickness within one coating unit.

• Journal of the Korea Society of Computer and Information
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• v.26 no.1
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• pp.45-55
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• 2021

This paper has proposed an algorithm that detecting for dense small vehicle in large image efficiently. It is consisted of two Ensemble Deep-Learning Network algorithms based on Coarse to Fine method. The system can detect vehicle exactly on selected sub image. In the Coarse step, it can make Voting Space using the result of various Deep-Learning Network individually. To select sub-region, it makes Voting Map by to combine each Voting Space. In the Fine step, the sub-region selected in the Coarse step is transferred to final Deep-Learning Network. The sub-region can be defined by using dynamic windows. In this paper, pre-defined mapping table has used to define dynamic windows for perspective road image. Identity judgment of vehicle moving on each sub-region is determined by closest center point of bottom of the detected vehicle's box information. And it is tracked by vehicle's box information on the continuous images. The proposed algorithm has evaluated for performance of detection and cost in real time using day and night images captured by CCTV on the road.

• Clean Technology
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• v.24 no.2
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• pp.112-118
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• 2018

Thermo-responsive polymers that exhibit phase transition in response to temperature change can be used as materials for smart windows because they can control solar light transmission depending on the outside temperature. The development of thermo-responsive polymers for smart windows that can be used over a wide temperature range is desirable. To obtain high performance smart windows materials, three-dimensional thermo-responsive poly(N-isopropylacrylamide) (PNIPAm) gels were prepared by free radical polymerization from monomer N-isopropylacrylamide, N, N'-methylenebis acrylamide (MBAm) as a crosslinking agent, ammonium persulfate (APS) as a strong oxidizing agent/tetramethylene diamine as a catalyst, and a mixture of two solvents (water/glycerol). This study examined the effect of glycerol content on the lower critical solution temperature (LCST), freezing temperature and the solar light transmittance of crosslinked PNIPAm gel films. The LCST and freezing temperature of PNIPAm gel films were found to be significantly decreased from 34.3 and $6.3^{\circ}C$ to 28.2 and $-6.5^{\circ}C$ with increasing glycerol content from 0 wt% to 10 wt%, respectively. It was found that the transparent PNIPAm gel films at $25^{\circ}C$ (temperature < LCST) were converted to translucent gels at higher temperature ($45^{\circ}C$) (temperature > LCST). These results suggested that the crosslinked PNIPAm gel materials prepared in this study could have high potential for application in smart glass materials.

• Journal of Families and Better Life
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• v.28 no.5
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• pp.25-38
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• 2010

The purpose of this study was to investigate the trend changes of the health characteristics and the elements of Han-Ok appeared in the articles of the daily newspaper, and to provide basic information for applying to the healthy housing for the public living in modern society and furthermore the various facilities for healing. For the study, the relevant articles of 4 daily newspapers published from 1st of January in 1960 to 28th of February in 2010 were collected and analyzed. The results of the study were as follows: First, the articles about the health characteristics and the elements of Han-Ok have rapidly grown since the year of 2000. Especially, the residents' interviews, case reports and actual living condition of Han-Ok recently tend to increase. Second, the health characteristics of Han-Ok in the recent articles were focused more on the mental and social health than on the physical health. The physical health had the characteristics of the block of hazard environments, the offer of good quality environments, and the enhancements of residents' health. The mental health consisted of the psychological comfort, the sensory satisfaction and the emotional growth. There have been improvements of family relationships and the interactions with neighbors in the characteristics of social health since 2000. Third, the health elements of Han-Ok in terms of architecture and interior design were the structure, space, material, doors & windows, furniture & props, nature, and villages. The material elements were more stressed before 2000, but the spaces and the nature elements were highly focused after 2000 and the structure elements were steadily high regardless of years. Fourth, of the health elements, the structure and the material had the high effects on the physical health characteristics, on the other hand the spaces and the nature influenced more on the mental health. On-dol, Ma-dang, Dae-cheong, Ma-ru, soil, wood, Changhoji, natural environments, and doors & windows were the detail health elements which had high effects on the health characteristics of Han-Ok. For the future study, the experience based in-depth studies of the residents living in Han-Ok are suggested to grasp the actual effects of Han-Ok on the health. The professional consultations are also needed for the extracts of the health characteristics of Han-Ok and the functional elements which can be applied to the modern buildings.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.171-176
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• 2004

Image matching is fundamental process in photogrammetry and computer vision to identify and to measure corresponding features on the multiple images. Uniqueness of the matching entities and robustness of the algorithm are the key issues that have influence on quality of the matching result. The optimal solution could be obtained by utilizing appropriate matching entities in the first place. In this study, candidate matching points were extracted by interest operator, and an area-based matching method was applied with characteristics of the gray value distribution as the matching entities. The characteristic information is based on the concept of "intrinsic image" (or parameter image). The information was utilized as additional and/or complementary matching entities. Matching on interest points with the characteristic information resulted in high quality of matching because matching windows were created with surrounding pixels of the interest points that contain distinct and unique features. The experiment shows that matching quality and reliability increase by exploiting interest operator, and the characteristic information has potential to be matching entity.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.409-412
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• 2002

The delta modulation used for controlling the speed of an induction motor has high peak of harmonic spectrum at low speed range causing acoustic noises in the induction motor. This paper proposes to suppress the harmonics by synchronizing the reference signal with the hysteresis windows for controlling the distribution of the switching frequency. As a result we can decrease the peak of harmonic spectrum. The simulation results show that the peak spectrum of harmonics can be reduced up to 60%.

• KIEAE Journal
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• v.15 no.1
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• pp.83-88
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• 2015

This study aims to develope the light-weight PV blinds with windows and to investigate the shading analysis by the control conditions. For the study, the polycarbonate characteristics and coating methods are analyzed and the PV blind design for a small office is suggested. Also, the mock-up model of a suggesting system was made. The field tests were controled based on a solar altitude under clear sky conditions. As results, it is necessary to use a polycarbonate instead of a tempered glass for a light-weight PV. The shading effects of blind systems are high in slat angle $30^{\circ}$ and low in $0^{\circ}$. Also, the shading ratio is more affected by solar latitude than solar altitude. The shading change rate is relevantly constant on the solar altitude.

• Journal of the Korean Home Economics Association
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• v.41 no.10 s.188
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• pp.117-128
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• 2003

This study investigated the consumers' awareness and information needs towards foodborne illness. Data were collected from 504 adults in Seoul, Daegu and Busan by the self-administered questionnaire. Frequencies, $X^2$ test and regression analysis were conducted by SPSS Windows. The results of this study were as follows: (1) the consumers' concerns and information needs about foodborne illness were generally high, (2) about four-fifths of the subjects were extremely worried about foodborne illness caused by fish, (3) about two-thirds answered that the major factor of foodborne illness in cooking was unfreshed or contaminated food stuffs, (4) the respondents primarily wanted to get the information about the method to choose fresh food, and (5) the result of the regression analysis showed educational attainment and concerns about foodborne illness were the factors affecting the consumers' information needs.

• Korean journal of food and cookery science
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• v.26 no.5
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• pp.649-654
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• 2010

This study investigated the recognition of and preference for consumer root vegetables for the improvement of fresh-cut root vegetable quality. The questionnaires consisted of questions on general preference, purchasing locations and quality factors. Answers to 286 questionnaires were analyzed both descriptively and quantitatively using SPSS for Windows (Version 14.0). The principal results were as follows: 37% of the respondents preferred potatoes to other root vegetables; 52% purchased at wholemarket. Most consumers preferred fresh-cut root vegetables; 56% were un-satisfied with fresh-cut vegetables quality as high quality agents. The most considered factor in purchasing fresh-cut root vegetables was shape/appearance.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.696-701
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• 2002

This paper describes some results of change detection in Tokyo metropolitan area, Japan , using the Landsat TM data, and methods to quantify the ground cover classes. The changes are analyzed using the measures of not only conventional spectral classes but also a set of landscape indices to describe spatial properties of ground cove types using fractal dimension of objects, entropy in the specific windows defining the neighbors of focusing locations. In order eliminate the seasonal radiometric effects on TM data, an automated class labeling method is also attempted. Urban areas are also delineated automatically by defining the boundaries of the urban area. These procedures for urban change detection were implemented by the unified image computing methods proposed by the author, they can be automated in coherent and systematic ways, and it is anticipated to automate the whole procedures. The results of this analysis suggest that Tokyo metropolitan area was extended to the suburban areas along the new transportation networks and the high density area of Tokyo were also very much extended during the period between 1985 and 1995.