• Plant Journal
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• v.18 no.1
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• pp.55-61
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• 2022

In this study, I analyzed the effect of slagging caused by blending bituminous coal and subbituminous coal while maintaining the generator output, combustion conditions, and ventilation conditions for 870MW thermal power plant designed with bituminous coal. Accordingly I proposed an acceptable method of blending coal method. the blending ratio of sub-bituminous coal was adjusted to 10%, 20%, 40%, 60%, 80%, etc. to confirm ultimate analysis, proximate analysis, ash fusion temperature change, slagging indices, etc. Proper blending coal conditions are blending with sub-bituminous coal at 40% or less, ratio of base component to acid component(B/A) is 0.4 or less or 1 or more, total alkali(TA) is 3.5 or less, fusion slagging index(Rfs) is 1,345℃ or more, and ash content is 13% or less in ultimate analysis, the ash content in proximate analysis is 15% or less, and the initial deformation temperature(IDT) should be at least 1,200℃ or more

• Journal of Korea Society of Industrial Information Systems
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• v.29 no.1
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• pp.1-13
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• 2024

This study aims to provide a customized dynamic kiosk screen that considers user characteristics to cope with changes caused by increased use of kiosks. In order to optimize the screen composition according to the characteristics of the digital vulnerable group such as the visually impaired, the elderly, children, and wheelchair users, etc., users are classified into nine categories based on real-time analysis of user characteristics (wheelchair use, visual impairment, age, etc.). The kiosk screen is dynamically adjusted according to the characteristics of the user to provide efficient services. This study shows that the system communication and operation were performed in the embedded environment, and the used object detection, gait recognition, and speech recognition technologies showed accuracy of 74%, 98.9%, and 96%, respectively. The proposed technology was verified for its effectiveness by implementing a prototype, and through this, this study showed the possibility of reducing the digital gap and providing user-friendly "barrier-free kiosk" services.

• Journal of the Korean Dietetic Association
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• v.2 no.2
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• pp.181-198
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• 1996

This study was carried out to investigate effects of general characteristics of the Korean dietician on job satisfaction. The subjects were 2987 dieticians who responded to the questionnaire distributed at the annual education program of the Korean Dietetic Association in 1995. The results are followings: 1. The level of the job satisfaction of Korean dieticians was low for payment, work environment, and value achievement as a dietician, while it was relatively high for the relationship with colleagues. The other parts of job satisfaction, such as work load, work contents, supervision by senior, participation of policy decision and etc were above average. 2. Dieticians who were older and/or who had worked longer than others had significantly higher job satisfaction in all fields. 3. Dietician who received college education showed significantly lower job satisfaction in all fields than did dieticians with B.A. and M.A. degree. 4. Dieticians with low position at the work had significantly lower job satisfaction in all fields than had dieticians with higher position.

• Journal of Korean Society for Geospatial Information Science
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• v.9 no.1 s.17
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• pp.27-38
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• 2001

The GIS construction project using the Digital Map has been progressed actively since the enforcement of NGIS project in 1995. But, the Digital Map actually can't use directly in building GIS because of many defects of the digital map such as geometric features errors(the overshoot/undershoot of line or the opening of polygon), non-topology etc. Many advanced countries in GIS has provided users Framework Data which is generated topology defined spatial relationships and used as a basic data of national geospatial information. In this study, we proposed the definition and the scope of Framework Data as a basemap of the Nation Geospatial Information and studied for the management and construction of the Transportation/Road Framework Data which is a core and basic data among them.

• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2246-2248
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• 1997

This paper presents a high-frequency inverter type high-voltage power supply for X-ray equipments. The high-voltage generator consist of an inverter unit including the SR(Series Resonance) type PSC(Phase-Shifted Control) PWM circuit adopting IGBT as the switching power device and high-voltage unit including the CW(Cockcroft Walton) circuit. When the X-ray equipment is radiographing at large power for a short time, this generator operates through feedback voltage mode control to obtain a high speed leading edge and low ripple. The operating modes and design consideration of the proposed power supply are given. Issues in the design of high-voltage divider for high voltage measuring. Experimental results are presented to verify the performance of the designed power supply for varying load conditions. The proposed apparatus has several advantages, e.g., the fast rising time of tube voltage, accuracy and reduced component size etc.

• Korean journal of applied entomology
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• v.46 no.1 s.145
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• pp.123-129
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• 2007

An artificial insemination instrument of bumblebee queens was firstly developed. This instrument consists of location tube, transfer tube, holding tube, head product, and probe apparatus for reproductive tract etc. This instrument was designed to minimize stress and damage of reproductive tract of bumblebee queens. The regulator handle apparatus in artificial insemination instrument was used the principle of lever, that manipulates easy, accurate and rapid insemination of bumblebee queens. By using this instrument, the insemination rate was over 90%. This instrument will be useful for the breeding and conservation of excellent character of bumblebees.

• Composites Research
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• v.16 no.4
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• pp.22-28
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• 2003

This article deals with the manufacture and test results of asbestos-free friction material for Aluminium at toy disk. In order to obtain optimum formulation, various formulations of fibres, matrix, modifiers, fillers, etc were designed and evaluated. The constant friction and brake dynamometer tests were performed to know weak and strong point for each friction material. The C21 formulation of various tested formulations exhibited superior friction constant(0.38∼38), fade rate (18%) by JASO C406 test mode and maximum wear 1.6 mm. disc wear 0.08 mm by JASO C427 test mode. The surface morphology of AL alloy disk(before and after test) was observed by Scanning Electron Microscope(SEM) and Image Analyzer.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.144-152
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• 2013

PRT(Personal Rapid Transit) system is a new transportation system which will meet increasing demands of traffic in Korea. It is also an environment-friendly transportation and automatically operated. For these reasons, researches on the PRT system are actively undergoing, but the PRT vehicles have different forms of subway, bus, etc. There are no design standards to evaluate structural integrity, yet. In this paper, Structural design specifications are derived, which are based on the performance test standard for EMU and the ASCE-APM standards. We also perform the static and fatigue analyses by FE simulation and suggest strategies to improve an initial structure design. In addition, we derived the design specifications for energy-absorbing structures to meet the conditions of the collision scenarios predefined from a view point of operation safety.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.2
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• pp.249-255
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• 2014

So many drinking water treatment plants are under various difficulties by new reinforced effluent standards. Since the target turbidity, much higher than annual average, for designing sludge thickener have to be set to confront high turbidity season, the sludge at thickener should be put up for a long time during usual days. So the soluble manganese and chloroform may be formed under the anaerobic environment in the sludge thickener when the sludge retention time is longer with low turbidity. This phenomenon results in difficulties to keep regulatory level of the discharged effluent. For an effort to overcome the problems, a sludge aeration was successfully implemented into the thickening process. As a result, the final effluent quality and sludge volume were much improved; 41 % of manganese, 62 % of chloroform and 35 % of sludge volume. Additionally, effluent quality was improved ; 61 % of Manganese on aeration with pH control and we could make sure of stability effluent quality despite a long sludge retention time. We recommended the standard of installation sludge aeration equipment to nationally supply water treatment plant under effluent water quality problem ; Manganese, Chloroform, etc.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3304-3310
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• 2010

This study solves the decision making problems for TFT-LCD manufacturing supply chain with demand and price uncertainties by establishing robust production and distribution strategies. In order to control the decisions regarding production graded by quality, inventory level and distribution, this study develop scenario model based stochastic mixed integer linear programs (SMILPs) that consider demand and price uncertainties as well as realistic constraints such as capacities etc. The performance of the solution obtained from the SMILPs using robust algorithms will be evaluated through various scenarios.