• Journal of KIISE:Computer Systems and Theory
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• v.30 no.9
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• pp.477-486
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• 2003

In combinatorial auctions buyers nay bid for arbitrary combinations of goods. But determining the winners of combinatorial auctions who maximize the profit of a seller is known to be NP-complete. A branch-and-bound method can be one of practical algorithm for winner determination. However, bid selection heuristics play a very important role in the efficiency of a branch-and-bound method. In this paper, we designed and implemented an algorithm which used a branch-and-bound method and Linear Programming for winner determination in combinatorial auctions. We propose new bid selection heuristics which consider a branching bid and conflicting bids simultaneously to select a branching bid in the algorithm. In addition, upper bounds are reused to reduce the running time in specific cases. We evaluated the performance of the algorithm by experiments with five data distributions and compared our method with others. The algorithm using heuristics showed a superior efficiency in two data distributions and a similar efficiency in three distributions.

• Journal of the Korean Vacuum Society
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• v.17 no.2
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• pp.81-89
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• 2008

Atomic behavior during ion beam sputtering was investigated by using classical molecular dynamics simulation. When Ar ion bombards on Au and Pd(001) surface with various incidence energies and angles, some atoms which gained substantial energy by impacting Ar ion were sputtered out and, simultaneously, others were landed on the surface as if surface atoms were redeposited. It was observed that the redeposited atoms are five times for Au and three times for Pd as many as sputtered atoms irrespective of both incidence energy and angle. From sequential ion bombarding calculations, contrary to the conventional concepts which have described the mechanism of surface pattern formation based only on the erosion theory, the redeposition atoms were turned out to play a significant role in forming the surface patterns.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.2-2
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• 2011

Single-walled carbon nanotubes (SWNTs) have been considered as a promising candidate for nextgeneration electronics due to its extraordinary electrical properties associated with one-dimensional structure. Since diversity in electronic structure depends on geometrical features, the major concern has been focused on obtaining the diameter, chirality, and density controlled SWNTs. Despite huge efforts, the controlled synthesis of SWNTs has not been achieved. There have been various approaches to synthesize controlled SWNTs by preparation of homogeneously sized catalyst because the SWNTs diameter highly depends on catalyst nanoparticles size. In this study, geometrically controlled SWNTs were synthesized using designed catalytic layers: (a) morphologically modified Al2O3 supporting layer (Fe/Al2O3/Si), (b) Mo capping layer (Mo/Fe/Al/Si), and (c) heat-driven diffusion and subsequent evaporation process of Fe catalytic nanoparticles (Al2O3/Fe/Al2O3/Si). These results clearly revealed that (a) the grain diameter and RMS roughness of Al2O3 supporting layer play a key role as a diffusion barrier for obtaining Fe nanoparticles with a uniform and small size, (b) a density and diameter of SWNTs can be simultaneously controlled by adjusting a thickness of Mo capping layer on Fe catalytic layer, and (c) SWNTs diameter was successfully controlled within a few A scale even with its fine distribution. This precise control results in bandgap manipulation of the semiconducting SWNTs, determined by direct comparison of Raman spectra and theory of extended tight binding Kataura plot. We suggest that these results provide a simple and possible way for the direct growth of diameter, density, and bandgap controlled SWNTs by precise controlling the formation of catalytic films, which will be in demand for future electronic applications.

• Journal of Information Science Theory and Practice
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• v.1 no.3
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• pp.60-73
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• 2013

The Database Industry Promotion Act was proposed at the National Assembly plenary session on July 26, 2012 and since then it has been in the process of enactment in consultation with all the governmental departments concerned. The recent trend of economic globalization and smart device innovation suggests a new opportunity and challenges for all industries. The database industry is also facing a new phase in an era of smart innovation. Korea is in a moment of opportunity to take an innovative approach to promoting the database industry. Korea should set up a national policy to promote the database industry for citizens, government, and research institutions, as well as enterprises. Above all, the Database Industry Promotion Act could play a great role in promoting the social infrastructure to enhance the capacity of small and medium-sized enterprises. This article discusses the background of the development of the Database Industry Promotion Act and its legislative processes in order to clarify its legal characteristics, including the meaning of the act. In addition, this article explains individual items related to the overall structure of the Database Industry Promotion Act. Finally, this article reviews the economic effects of the database industry for now and the future.

• Journal of Fashion Business
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• v.8 no.2
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• pp.56-68
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• 2004

Korean fashion industry is not exceptional in terms of positive offense of multinationals and management circumstance of corporations which is changeful momentarily. Accelerated by continuous industry growth and particular policy to promote fashion industry, Korean fashion industry has been inflated quantitatively. In this paper the author presents a effective model which is applicable to the area of outsourcing in Korean men's wear industry incomplete and non-systematic. Studying and analyzing the state of outsourcing in other industries which use advanced outsourcing systems, the author suggests how to customize their advanced systems to men's wear industry. For the successful outsourcing, fashion brands have to recognize the specialized ability of outsourcing companies, go into partnership with them horizontally and concede their own value, not only for cost reduction. On the other hand, outsourcing companies should mediate between two parties, fashion brands and manufacturers, have the ability to create new designs, be able to present merchandises that fashion brands want, invest money in developing creative designs and new products which have good quality, and handle many manufactures specialized in their own areas to play an important role in mediating fashion brand sand manufactures. In this paper, the author tries to study forward direction of specialized outsourcing companies theoretically and is going to apply this theory to men's wear industry to make Korean fashion industry survive in international market successfully.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.1
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• pp.59-67
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• 2015

Because reservoirs that supply irrigation water play an important role in water resource management, it is necessary to evaluate the vulnerability of this particular water supply resource. The purpose of this study is to provide water supply risk maps of agricultural reservoirs in South Korea using irrigation vulnerability model and cluster analysis. To quantify water supply risk, irrigation vulnerability indices are estimated to evaluate the performance of the water supply on the agricultural reservoir system using a probability theory and reliability analysis. First, the irrigation vulnerability probabilities of 1,346 reservoirs managed by Korea Rural Community Corporation (KRC) were analyzed using meteorological data on 54 meteorological stations over the past 30 years (1981-2010). Second, using the K-mean method of non-hierarchical cluster analysis and pre-simulation approach, cluster analysis was applied to classify into three groups for characterizing irrigation vulnerability in reservoirs. The morphology index, watershed area, irrigated area, and ratio between watershed and irrigated area are selected as the clustering analysis parameters. It is suggested that the water supply risk map be utilized as a basis for the establishment of risk management measures, and could provide effective information for a reasonable decision making on drought risk mitigation.

• Journal of the Ergonomics Society of Korea
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• v.25 no.4
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• pp.81-90
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• 2006

Despite the government promoting women's participation in the engineering field, some statistics show that it has yet to be achieved. Potential reasons for this phenomenon include lower level of applications by women, or inherent gender gap in the professional field. Therefore, this study attempted to find impact of gender on college admission from the Lens Model perspective and Signal Detection Theory. This study consisted of three phases: identifying the necessary cues used in the admission process, analyzing existing data, and conducting two experiments to identify the effect of gender on admission decisions. Although the college application consisted of many cues, only five cues, school ranking, GPA, SAT score, resident status, and gender, were used to capture the officers' judgment policies for engineering admissions. Two experiments were conducted to investigate the impact of the gender factor in college admission. The enrollment officers first were presented with the existing data without the gender and asked to make dichotomous judgments. Secondly, the officers were asked to perform the judgment task with the gender cue present. Results showed that the gender did not play an important role in the judgments as expected. However, ideographical analyses on judgment strategies revealed that there were significant differences between the admission officers. Possible training implications are discussed.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1704-1710
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• 2010

The structure of a 2D grid-like copper(II) complex [Cu$(NCO)_2$(pyz)](pyz=pyrazine) (1) consists of 1D chains of Cu-pyz units connected by double end-on (EO) cyanato bridges. Each Cu(II) ion has a distorted octahedral coordination, completed by the four EO cyanato and two pyrazine ligands. Magnetic interactions through EO cyanato and pyrazine bridges in 1 are discussed on the basis of DFT broken-symmetry calculations at the B3LYP level. For model dicopper(II) complexes I (bridged by cyanato) and II (bridged by pyrazine), electronic structure calculations reproduce very well the experimental couplings for the S = 1/2 ferromagnetic and antiferromagnetic exchange-coupled 2D system: the calculated exchange parameters J are +1.25 $cm^{-1}$ and -3.07 $cm^{-1}$ for I and II, respectively. The $\sigma$ orbital interactions between the Cu $x^2-y^2$ magnetic orbitals and the nitrogen lone-pair orbitals of pyrazine are analyzed from the viewpoint of through-bond interaction. The energy splitting of 0.106 eV between two SOMOs indicates that the superexchange interaction should be antiferromagnetic in II. On the other hand, there are no bridging orbitals that efficiently connect the two copper(II) magnetic orbitals in I because the HOMOs of the basal-apical NCO bridge do not play a role in the formation of overlap interaction pathway. The energy separation in the pair of SOMOs of I is calculated to be very small (0.054 eV). This result is consistent with the occurrence of weakly ferromagnetic properties in I.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.4
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• pp.25-35
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• 1999

This thesis is to newly understand the value and the meaning of Chonju Palkyong(全州八景) by the specific gravity in making a counter-proposal in other to improve the landscape identity of modern city and at the same time. I intended to group the grafting device for the preservation and regeneration of modern history cultural environment through the interpretation of landscape construction. The meaning system of Chonju Palkyong showed the symbolic system which a landscape construction, four directions and two places has and exhibited the landscape shape possessing a luxuriant local feature peculiar to Chonju, preserving visual bound language of a classical Palkyong. Especially, it implies the use of the substantial landscape experienced factor, the expressions about natural phenomena and the matter which has melted human living circumstances. The landscape construction and it's form show the system which forms the different time field, a far landscape and a mid distance landscape and a near landscape, etc., under the visual, psychological, scenic influenced area, preserving the feature of the similar and typical type of Sosang Palkyoung（瀟湘八景) which intended to seek the local reappearance of the famous site experienced type and natural matter which famous place and local conduct were combined. The object space of Chonju Palkyong area representing the nature of historical landscape cultural assets, pushed by the greater part of the development based theory, shows injured aspects, but needs to play a part to seek such a up-to-date successive plan as the reconstruction of the destroyed historical landscape area which motivated Palkyong, the establishment of useful area, the embodiment of the cultural identity of Palkyong area and the becoming of the educational cultural life space. The analysis of the landscape construction of Chonju Palkyong and the grouping of the modern successive plan which I considered in this thesis, will be able to become a fundamental data to carry out the preservation of historical landscape and the landscape plan in the city.

• Management & Information Systems Review
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• v.25
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• pp.243-273
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• 2008

A new research paradigm is emerging within organizational behavior, in both theory and empiricism, based on the increasing recognition of the importance of emotions to organizational life. This paper suggest that emotion intelligence play a moderate variables in relationship of emotion labor and emotional exhaustion. More specifically, it is proposed that emotional intelligence, the ability to understand and manage emotions in the employee self and others, contribute to effective emotions management in organizations. Four major aspects of emotion labor, appraisal and expression of emotion in oneself, appraisal and recognition of emotion in others, regulation of emotion in oneself and use of emotion to facilitate performance, are described. Also, the emotional intelligence are consists of four aspects, frequency of appropriate emotional display, attentiveness to required displayed rules, variety of emotions to be displayed and emotional dissonance. Then I propose how emotional intelligence contributes to of relations the emotion labor and emotional exhaustion. The purpose of this research is to investigate the impact of emotion labor to employee's emotional exhaustion to explore the moderating effects of the emotional intelligence between the emotion labor and emotional exhaustion. To complete the research the data were collected through a questionnaire from 147 employees from service company. After multi-hierarchical regression analysis, the outcomes of this study are the employee's emotional exhaustion are affected negatively by the three factors: major aspects of emotion labor, regulation of emotion in oneself, use of emotion to facilitate performance, make the moderation effect between emotion labor and emotional intelligence. These results indicate that instilling in others an appreciation of the importance of work activities: encouraging of true expression individual emotions, generating and maintaining well emotional climate and cooperation situations, and managing a meaningful environment for an organizational life.