• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.194-194
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• 2003

• Tribology and Lubricants
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• v.38 no.4
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• pp.152-161
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• 2022

Chemical mechanical planarization (CMP) is a technology that planarizes the surfaces of semiconductor devices using chemical reaction and mechanical material removal, and it is an essential process in manufacturing highly integrated semiconductors. In the CMP process, a conditioning process using a diamond conditioner is applied to remove by-products generated during processing and ensure the surface roughness of the CMP pad. In previous studies, prediction of pad wear by CMP conditioning has depended on numerical analysis studies based on mathematical simulation. In this study, using an artificial neural network, the ratio of conditioner coverage to the distance between centers in the conditioning system is input, and the average conditioning density, standard deviation, nonuniformity (NU), and conditioning density distribution are trained as targets. The result of training seems to predict the target data well, although the average conditioning density, standard deviation, and NU in the contact area of wafer and pad and all areas of the pad have some errors. In addition, in the case of NU, the prediction calculated from the training results of the average conditioning density and standard deviation can reduce the error of training compared with the results predicted through training. The results of training on the conditioning density profile generally follow the target data well, confirming that the shape of the conditioning density profile can be predicted.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.6
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• pp.524-532
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• 2003

In this paper, a personal air-conditioning system considering the human thermal adaptability is analyzed. Although the conventional personal air-conditioner was proofed to be satisfactory in providing for the thermal comfort, it is being questioned on the term of its energy efficiency. Therefore, it is important and urgent to develop new types of personal air-conditioning system with sustainable control strategy that can ensure energy saving and thermal comfort simultaneously. In this study, we first examined the problems of the conventional personal air-conditioning system with field interview and laboratory experiment in terms of usage, management and thermal comfort, and proposed the energy-saving personal air-conditioning system considering the human thermal adaptation. Then a laboratory experiment was performed to analyze the characteristics of the human thermal comfort under severe indoor thermal conditions, which were controlled using a new personal air-conditioning unit designed according to the proposal. The results help to illustrate the alleviation effect of the new personal air-conditioning system, and indicate that the thermal alleviation time is useful to maintain the thermal comfort with efficient usage of energy.

• Journal of The Korea Institute of Healthcare Architecture
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• v.25 no.4
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• pp.27-35
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• 2019

Purpose: As the improvement in quality of medical environment and the spatial consideration for the prevention of infection in the hospital have become increasingly important in the recent years, specific and practical planning for air conditioning room's area has become a major issue accordingly. However, the air conditioning room tends to be discussed focusing on technical factors such as air conditioning systems that are irrelevant to building plans, while discussions of most departments related to the medical functions have actively taken placed. Therefore, this study aims to investigate the factors influencing the planning for the air conditioning room area, and through subsequent analysis of the area of the air conditioning room, to propose a way to improve effective planning for the air conditioning room area. Methods: This study examines the case hospitals that fall into two types: each floor supply system and concentrated supply system, and compares and analyzes the air conditioning room area-related factors and the characteristics of changes in the interior of air conditioning room before and after remodeling through air conditioning floor plan of those case hospitals. Results: The air conditioning room can be classified into the net area of the functional space such as duct passages, and the public area such as aisle space, and of those the public area is an important factor in calculating the area of the air conditioning room. The public area of the air-conditioning room should not be planned considering only the spaces for mobile passage or maintenance activities, but should be planned taking into account internal changes such as expansion and replacement of equipment in the future from the beginning. Implications: When planning a medical facility, it is used as basic data for the planning of the air conditioning room area, which is a significant fixed factor in the initial setting.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.5
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• pp.480-487
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• 2022

As a process to improve the insulation performance of VIs (Vacuum Interrupters), AC voltage conditioning is generally adopted by many manufacturers. Although the insulation performance is enhanced easily with AC Voltage conditioning, it has limitations when high recovery voltage is required due to high voltage rate or capacitive current switching. In particular, impurities such as oxides segregated on the electrode surface can be removed not by the energy level of the voltage conditioning but by the higher energy level achieved by the current conditioning process In this article, the current conditioning was carried out in various conditions and its validity was examined. The current conditioning was processed by changing the amplitude of applied current, arc time, the number of tests, and frequency. The insulation performance and the status of contact surface were checked as well. We concluded that as the applied charge quantity and the conditioning coverage area increase, the conditioning effect is much higher.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.334-339
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• 2007

This paper is concerned with economic analysis and comparison between hybrid and central air conditioning system by TRNSYS simulation and Life Cycle Cost(LCC) analysis. Hybrid air conditioning system that is using VAV for interior zone and system air-conditioner for perimeter zone is installed in building A. Central air conditioning system is composed of VAV and convector. The simulation was carried out in mode temperature level control using TRNSYS 16. From the result of simulation and LCC analysis, hybrid air conditioning system was better than central air conditioning system in initial cost and energy consumption.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.2
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• pp.55-63
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• 2013

For a large-scale semiconductor manufacturing clean room, the energy consumed in an outdoor air conditioning system to heat, humidify, cool and dehumidify incoming outdoor air is very large. In particular, the energy requirement to humidify outdoor air in the winter season is generally known to be high. Recently, in order to overcome the high energy consumption nature of a steam generator in a conventional steam humidification type outdoor air conditioning system, an air washer is often introduced instead of the steam generator in the outdoor air conditioning system, which can be called a water spray humidification type outdoor air conditioning system. Therefore, the assessment and comparison of the annual energy consumed in the steam humidification type and the water spray humidification type outdoor air conditioning systems deserves to be examined in order to reduce the outdoor air conditioning load of a clean room. In the present study, a numerical analysis was conducted to obtain the annual electric power consumption of the two outdoor air conditioning systems. It was shown from the comparison of the numerical results that the water spray humidification type outdoor air conditioning system can reduce about 30% of annual electric power consumption of the steam humidification type outdoor air conditioning system.

• Tribology and Lubricants
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• v.38 no.1
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• pp.1-7
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• 2022

Chemical-mechanical polishing (CMP) process is a semiconductor process that planarizes a wafer surface using mechanical friction between a polishing pad and a substrate surface during a specific chemical reaction. During the CMP process, polishing pad conditioning is applied to prevent the rapid degradation of the polishing quality caused by polishing pad glazing through repeated material removal processes. However, during the conditioning process, uneven wear on the polishing pad is inevitable because the disk on which diamond particles are electrodeposited is used. Therefore, the abrasion of the polishing pad should be considered not only for the variables during the conditioning process but also when designing the CMP conditioning system. In this study, three design variables of the conditioning system were analyzed, and the effect on the pad wear profile during conditioning was investigated. The three design variables considered in this study were the length of the conditioner arm, diameter of the conditioner disk, and distance between centers. The Taguchi method was used for the experimental design. The effect of the three design variables on pad wear and uniformity was assessed, and new variables used in conditioning system design were proposed.

• Journal of the Korean housing association
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• v.6 no.2
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• pp.205-212
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• 1995

The objective of this study were to determine new air conditioning's selling possibility and discriminate it's market in Pusan and Daegu. The data were collected by using questionnaire. On the basis of the findings. These are follwing conclusions : Come to think of using rates of air conditioning. Function of air conditioning in house is not satisfied nowadays. Residents prefer it's function of cooling plus heating to only cooling in order to use a air conditioning in winter and the turning point of the season. And the air conditioning should be furnished economy, environment, convenience, amenity, safety.

• Proceedings of the SAREK Conference
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• 2005.06a
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• pp.219-219
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• 2005