• Journal of the Semiconductor & Display Technology
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• v.17 no.1
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• pp.66-70
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• 2018

This paper is about the analysis on the vibration characteristic of tooling units on the precision bed in turning and hobbing automatic lathe for precision machining. An automatic lathe operating at about 12,000 RPM is a critical factor in the self-weight stress and deformation of the bed. Especially, the resonance frequency should be grasped in advance to prevent abnormal vibration that may occur during processing. If the wrong bed is used, the resonant frequency can have a fatal influence on the precision machining and increase the defective rate of precision machined parts such as semiconductor parts. In this paper, vibration characteristics were evaluated through static load and resonance frequency analysis of automatic lathe bed. As a result, the maximum stress was 14.52 MPa, the maximum deformation amount was $12.15{\mu}m$, and the natural frequency was 189.43 Hz. The resonance frequency was calculated as 500 Hz, and the stability was confirmed by being in the range of 200 Hz or more, which is the processing condition.

• Asian Journal of Innovation and Policy
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• v.3 no.1
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• pp.1-24
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• 2014

Policy planners in Asia readily covet high technology districts and regional systems of innovation such as Silicon Valley. We examine the law's role, by way of covenants not to compete (競業禁止條項) in the development of Silicon Valley by reviewing the literature from 1999 through 2013. The research suggests that in certain high-tech districts such as Silicon Valley, there are greater gains in the innovation of a region by prohibiting CNCs. While we emphasize CNC law as the main legal determinant to Silicon Valley's success, the application of trade secret law and the inevitable disclosure doctrine are also factors that can aid or restrict the mobility and knowledge spillover of a region. Even with much explored, perspectives are lacking from a regional innovation systems analysis, and more so in the context of Asian nations. To tackle these gaps, three analytical frameworks are presented that entails labor law, law and economics, and law and innovation. And from within the law and innovation framework, research is introduced in the hope that future discussions on Asian regional innovation systems consider the legal foundation of Silicon Valley.

• The Journal of the Korea Contents Association
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• v.21 no.8
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• pp.356-366
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• 2021

The high-tech industry, a leader in the national economy, has a larger investment cost compared to general buildings, a shorter construction period, and requires continuous investment. Therefore, accurate construction cost prediction and quick decision-making are important factors for efficient cost and process management. Overseas, the construction information classification system has been standardized since 1980 and has been continuously developed, improving construction productivity by systematically collecting and utilizing project life cycle information. At domestic construction sites, attempts have been made to standardize the classification system of construction information, but it is difficult to achieve continuous standardization and systematization due to the absence of a standardization body and differences in cost and process management methods for each construction company. Particular, in the case of the high-tech industry, the standardization and systematization level of the construction information classification system for high-tech facility construction is very low due to problems such as large scale, numerous types of work, complex construction and security. Therefore, the purpose of this study is to construct a construction information classification system suitable for high-tech facility construction through collection, classification, and analysis of related project data constructed in Korea. Based on the WBS (Work Breakdown Structure) and CBS (Cost Breakdown Structure) classified and analyzed through this study, a code system through hierarchical classification was proposed, and the cost model of buildings by linking WBS and CBS was three-dimensionalized and the utilized method was presented. Through this, an information classification system based on inter-relationships can be developed beyond the one-way tree structure, which is a general construction information classification system, and effects such as shortening of construction period and cost reduction will be maximized.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.1
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• pp.15-21
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• 2015

The purpose of this paper is to analyze thermal characteristics of the heat sinks to maximize the thermal diffusivity for LED floodlight. The 2 kind of samples were prepared by vapor chamber manufacturing technology using the heat pipe principle. It was analyzed the maximum temperature reduction effect and the thermal diffusion from the heat source depending on the types of chambers with 3 kind of working fluids. As a result, it was confirmed that thermal conductivity 23% increased, GVC-R type than IVC-R type.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.600-604
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• 1991

In this paper, an advanced PWM modulation strategy for driving a variable-speed induction motor is introduced. According to this method, the technique of efficiently eliminating harmonics component is achived. A switching pattern was computed making use of the near-proportionality of voltage and frequency in AC machines operating with constant flux. At low magnitudes and low frequencies of the foundamental, many more harmonics are eliminated than at high magnitudes and frequencies. In order to keep the inverter switching frequency constant over the output frequency range, chopping times diminishes as the frequency of the fundamental increases.

• Korean Management Science Review
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• v.28 no.2
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• pp.75-92
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• 2011

This study investigates how cognitive and affective conflict affect performance and social outcomes in the new product situation. We examine the corporate, project, and personal characteristics that determine the level of inter-functional conflict between marketing and R&D. From a survey of Korean high-tech companies, we found : (1) time pressure was positively related to cognitive and affective conflict, (2) joint reward systems, interdepartmental connectedness, and years of education were negatively associated to cognitive conflict, (3) while cognitive conflict was positively related to new product creativity and NPD performance, affective conflict was negatively associated to marketing-R&D integration and perceived effectiveness of the relationship, as well as new product creativity and NPD performance.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.11a
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• pp.177-178
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• 2006

This plan is for a different type of welfare facilities devised by analyzing problems with existing welfare centers and focusing on connection with residents and link between culture and welfare and among generations. In terms of re-development plan of Youngsun-2-dong, Youngdo-gu, Busan and the neighborhood under this plan, Youngsun-dong, Youngdo-gu is one of the densely populated districts of the aged, with lower growth rate and poor housing and welfare facilities. However, the district has a blessed natural environment and historical site of cultural relics of the Neolithic Age as well as growth potential as a logistics center with broader network of roads linking with Bukhang Bridge when Namhang Bridge construction is complete, showing the aspiration for change toward hi-tech maritime city in the 21st century of Youngdo-gu. This plan is expected to promote unity between the old and children, protection from social marginalization, and re-socialization education and set the stage for participation and solidarity of residents in the community.

• Journal of Conservation Science
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• v.5 no.2 s.6
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• pp.15-24
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• 1996

Th)s study was carried out of the historical characters and textile coservations for Mrs. Danha Lee's Wonsam. As the textile material was silk, dry cleaning method was suggested. The solvents for dry cleaning were n-hexane, n-decane, and benzene. During the second cleaning process, the dry soap(HI-TECH, 120:1, volume ratio) was added to the mixed solvents. The reaction's temparature was $20^{\circ}C$, and the reaction's time was 30 minuutes. It seemed to be a gift for hot from the Royal Family because of the attachment of pheonlx hungbae. This wonsam was decorated symmetrically by gold weaving yarn, the basic fabric was green silk satin with glorius letters and floral patterns. It was made on the 17th C and the oldest thing among them.

• Journal of the Korean Graphic Arts Communication Society
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• v.14 no.1
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• pp.17-29
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• 1996

N-substituted acrylamide hydrogel is reported to have the feature of bing transparent and sensitive enough to response to a temperature stimulus below the temperature of phase transition. Especially at the near of 35 C it becomes shrunk and opaque very quickly. It has also the characteristic of reversing swelling and shrinking. The experiment showed that it is possible to produce a functional gel of super water absorption with the process of free radical polymerizing PVA(polyvinylalcohol) and PAA(polyacrylamide), and crosslinking. The ratio of shrinking and swelling caused by copolymerization rises 10% to 80% at the each temperature of 20 C, 30 C, 40 C, respectively. Phase transition temperature of this gel by copolymerization is50 C while that of ordinary N-substituted acrylamides is between 32~35 C. This temperature reaches the rearing limit of animals and plants so that volumetric transition polymer gel can be ulilized in varying fields such as agriculture/gardening which are water-using field, on-off switch sensing temperature and volumetric variation, processing of liquid wastes and civil engineering works, architecture and electronics. We have no doubt that this material will be the high-functional resin in the hi-tech age of the near future.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.02a
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• pp.169.1-169.1
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• 2009