• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.176-180
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• 2001

There are several factors causing re-work in CMP process such as improper polish time calculation by operator. removal rate decline of the polisher, unstable in-suit pad conditioning, slurry supply module problem and wafer carrier rotation inconsistancy. And conclusively those fundimental reason for the re-work rate increasement is mainly from the cycle time delay between wafer polish and post measurement. Therefore, Wafer thickness measurement in wet condition could be able to remove those improper process conditions which may happen during the process in comparison with the conventional dried wafer measurement system and it can be able to reduce the CMP process cycle time. CMP scrap reduction by overpolish, re-work rate reduction, thickness control efficiency also can be easily achieved. CMP Equipment manufacturer also trying to develop integrated system which has multi-head & platen, cleaner, pre & post thickness measure and even control the polish time from the calculated removal rate of each polishing head by software. CMP re-work problem such as over & under polish by target thickness may result in the cycle time delay. By reducing those inefficient factors during the process and establish of the automatic process control, CLC system need to be adopted to maximize the process performance. Wafer to Wafer Polish Time Feed Back Control by measuring the wafer right after the polish shorten the polish time calculation for the next wafer and it lead to the perfact Post CMP target thickness control capability. By Monitoring all of the processed the wafer, CMP process will also be stabilize itself.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.176-180
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• 2001

There are several factors causing re-work in CMP process such as improper polish time calculation by operator, removal rate decline of the polisher, unstable in-suit pad conditioning, slurry supply module problem and wafer carrier rotation inconsistency. And conclusively those fundimental reason for the re-work rate increasement is mainly from the cycle time delay between wafer polish and post measurement. Therefore, Wafer thickness measurement in wet condition could be able to remove those improper process conditions which may happen during the process in comparison with the conventional dried wafer measurement system and it can be able to reduce the CMP process cycle time. CMP scrap reduction by overpolish, re-work rate reduction, thickness control efficiency also can be easily achieved. CMP Equipment manufacturer also trying to develop integrated system which has multi-head & platen, cleaner, pre & post thickness measure and even control the polish time from the calculated removal rate of each polishing head by software. CMP re-work problem such as over & under polish by target thickness may result in the cycle time delay. By reducing those inefficient factors during the process and establish of the automatic process control, CLC system need to be adopted to maximize the process performance. Wafer to Wafer Polish Time Feed Back Control by measuring the wafer right after the polish shorten the polish time calculation for the next wafer and it lead to the perfect Post CMP target thickness control capability. By Monitoring all of the processed the wafer, CMP process will also be stabilize itself.

• Journal of the Korean Home Economics Association
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• v.43 no.2
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• pp.203-229
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• 2005

The purpose of this study was to explore the perceived quality of life of Korean university students'. The perceived quality of life was composed of three dimensions: emotion, cognitive efficiency, and satisfaction. The study results were as follow: 1. Korean university students felt more positive emotions when they spent time for social activities. 2. In the cognitive efficiency, social activities also scored highly of 5 questions, but in the item of "awareness of another person's eye", productive activities were higher. 3. Korean university students were more satisfied with themselves when they spent time for productive activities. However, they were more satisfied with their work itself when the work was social activities. 4. Korean university students' emotions, cognitive efficiencies, and satisfaction were significantly different by socio-graphic variables and context.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.2
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• pp.595-609
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• 2020

In this study, we propose a decentralized mathematical model for predictive control of a system of multi-autonomous unmanned aerial vehicles (UAVs), also known as drones. Being decentralized and autonomous implies that all members make their own decisions and fly depending on the dynamic information received from other unmanned aircraft in the area. We consider a variety of realistic characteristics, including time delay and communication locality. For this flocking flight, we do not possess control for central data processing or control over each UAV, as each UAV runs its collision avoidance algorithm by itself. The main contribution of this work is a mathematical model for stable group flight even in adverse weather conditions (e.g., heavy wind, rain, etc.) by adding Gaussian noise. Two of our proposed variance control algorithms are presented in this work. One is based on a simple biological imitation from statistical physical modeling, which mimics animal group behavior; the other is an algorithm for cooperatively tracking an object, which aligns the velocities of neighboring agents corresponding to each other. We demonstrate the stability of the control algorithm and its applicability in autonomous multi-drone systems using numerical simulations.

• Journal of Computational Design and Engineering
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• v.3 no.4
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• pp.398-413
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• 2016

This work describes the design and development of a new drying system for a rollover carwash machine with the support of numerical tools. The drying system is composed of a pair of stationary vertical dryers and a moveable horizontal dryer that can adjust itself to the contour of a vehicle. After the definition of the dryers' concept, their performance was assessed individually to check their internal flow pattern and to improve their airflow distribution. These issues are expected to provide feedback on redesign and geometric optimization of the dryers. After redesign of the dryers separately, the behaviour of the complete drying system was studied on actual vehicle models, representative of the shortest and tallest dimensions that can be washed with the existing carwash machine sector. The drying efficiency of the whole system was studied by calculation of shear stress distribution on various surfaces of a given vehicle. The results allowed concluding that the overall drying performance of the design system is very good and assure adequate drying on most vehicles surfaces. The results obtained from numerical studies were then validated with experimental measurements and a good agreement was found between the two. The procedure employed in this work can be applied to support the design and analysis of other mechanical drying systems.

• Culinary science and hospitality research
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• v.6 no.2
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• pp.79-95
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• 2000

In the modern industrial society, the management of human resources is regarded as an area as much important as the management itself. The development of human capacity is required to accomplish upgrading human resources quality. The objective of this study aims to seek the way to solve the problem of the job satisfaction of diner out company employee. The collecting data is analyzed by sass which is one of the computer. programs. This empirical research result shows some facts as follows : First, Significant differences between male and female in regard to job satisfaction were found. Second, No significant differences between unmarried and married in regard to job satisfaction were found. Third, Significant differences were found in the accomplishment and communication factor of job satisfaction according to the age, Fourth, Significant differences were found in the hard work environment and accomplishment factor of job satisfaction according to the education Fifth, Significant differences were found in the hard work environment factor of job satisfaction according to the major. Sixth, Significant differences were found in the wages, accomplishment , communication factor of job satisfaction according to the position. Seventh, Significant differences were found in the accomplishment and affinity factor of job satisfaction according to the period of the job. Eighth, Significant differences were found in the duty trait factor of jobs satisfaction according to the level of the pay. Ninth, Significant differences were found in the duty trait factor of job satisfaction according to the kind of the job. Tenth, Significant differences were found in job satisfaction according to the kind of diner out company.

• Korean Institute of Interior Design Journal
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• v.14 no.2 s.49
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• pp.95-103
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• 2005

This study is on the concept of Gunter Behnisch' s 'Situationsarchitektur'. Gunter Behnisch is known as the architect who have produced astonishing variety of different types of buildings since 1950s. His works always reflect his changing major concerns of architecture, which varied through his career such as flexibility and serial production in the 1960s, politics and place in the 1970s and 80s, and ecological issues in 90s and afterward. Behnisch says that the goal of architects' work is not so much the building as the situation to be created, and only such measures should be taken as in fortunate cases strengthen and give meaning to the situation that exists, or in less fortunate ones recreate it. The 'Situationsarchitektur' is realized through emphasizing transparency, humanity, public space, and open detail that could lead to a certain lightness and relaxedness in architecture not as an end in itself, but rather in the result. Architecture should be allowed to arise out of circumstances of use and construction, but form should not be imposed as a preconception. Also architecture should be strongly tied to time, space and local conditions. Behnisch tries to see the fundamentals of his work in such a way that subtlety and diversity develop of their own accord or are preserved as a reflection of a world.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1638-1644
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• 2007

The effect of carbon sources on tacrolimus production by a mutant strain of Streptomyces clavuligerus CKD 1119, an isolate from soil, was examined. Among the carbohydrates and oils tested in this work, a mixed carbon source of soluble starch and com oil was the best. An analysis of the culture kinetics also showed that, in contrast to the carbohydrates, the com oil was consumed later in the antibiotic production phase, implying that the oil substrate was the principal carbon source for the biosynthesis of tacrolimus, and this was directly proven by experiments using $^{14}C$-glucose and $^{14}C$-oleate substrates. Furthermore, com oil induced the formation of lipase by the mutant strain, whereas the addition of glucose significantly repressed lipase activity. The lipase activity exhibited by the FK-506-overproducing mutants was also observed to be directly proportional to their tacrolimus yield, indicating that a high lipase activity is itself a crucial factor for tacrolimus production. A feasibility study with a 200-1 pilot-scale fermentor and the best strain (Tc-XII-15322) identified in this work revealed a high volumetric and specific productivity of about 495 mg/l and 0.34 mg/mg dry mycelium, respectively.

• Journal of the Korea Institute of Building Construction
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• v.12 no.3
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• pp.291-298
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• 2012

For cold weather concreting, frost damage at early age is generated in the concrete, and problems such as delaying of setting and hardening and lowering of strength manifestation emerge due to the low outside air temperature at the early stage of pouring, making the selection of an effective curing method critically important. Unfortunately, the tent sheet currently used as the curing film for heating insulation at work sites, not only has the problems of inferior permeability and extremely deteriorated airtightness, but a phenomenon of continuous fracturing is also generated along the direction of fabric of the material itself, presenting difficult circumstances for maintaining adequate curing temperature. The aim of this study was to develop an improved bubble sheet type curing film for heating insulation of cold weather concrete by combining mesh-tarpaulin, which has excellent tension properties, with bubble sheet, which offers superior insulation performance. The analysis showed that the improved curing film in which BBS1 is stacked to MT was a suitable replacement for curing films currently in use, as it has better permeability, tension property, and insulation performance than the T type film used at work sites today.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.932-939
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• 2005

Recently, the lateral displacement of the passive piles which installed under the revetment on soft ground is very important during the land reclamation work along the coastal line. The revetment on the soft clay develops the lateral displacement of the ground when the revetment loading is exceeded a certain limit. The lateral displacement of ground causes an excessive deformation of under structure itself and develops lateral earth pressure against the pile foundation as well. Especially passive piles subjected to lateral earth pressures are likely to have excessive horizontal displacement and large bending moment, which induces structural failure of pile foundation and harmful effects on superstructure. The subject of study is to investigate the later displacement of pile foundation during the construction of container terminal at the south port of Incheon. Actual field measurement data and finite element method(FEM) by AFFIMEX Ver 3.4 were used to analyze the displacement of pile and the vertical settlement of soft ground. This analysis was carried out at each sequence of construction work.