• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.404-407
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• 2004

This Research suggested direction of development and analyzed necessity and given condition of CM(Construction Management) operation system of SOC private infrastructure project which is judged to grow up continuously from now on, Direction of development which is suggested in this research is largely there, (1)development of SOC private infrastructure project CM work standard process guide, (2)development of SOC Private Investment project feasibility study Performance standard, (3)checklist of SOC by stages and functionally private investment projects risk. Through this development, later we judge effect not only supply of a model case to artivate CM system but heightening of efficiency in domestic construction industry.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.258-265
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• 1995

Regeneration process of edaphic pine(Pinus densiflora) climax forest in Bulyung-gyegog, Uljin-gun, Kyungsangbuk-do, was studied. The height of dominant trees in the stands are 12 15m. Upper layers are highly dominated by pine trees and are randomly distributed. Pine trees in lower layer grow in a patch type. In the upper layer, the age distribution is likely one model type with mode of 60 and 80 years. In the horizontal distribution of these trees, some of the even-aged cluster constituted of several tree were found. For the first 25 years, the stem diameter increment rates in upper layer are higher than those in the middle layer. It could be concluded that after the forest canopy had been broken out, the seedlings established densely in a patch in the gap with the decreasing density and some of them, distributed in random, would constitute the canopy.

• Publications of The Korean Astronomical Society
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• v.7 no.1
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• pp.89-96
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• 1992

Recent spectroscopic observations indicate concentration of dark masses in the nuclei of nearby galaxies. This has been usually interpreted as the presence of massive black holes in these nuclei. Alternative explanations such as the dark cluster composed of low mass stars (brown dwarfs) or dark stellar remnants are possible provided that these systems can be stably maintained for the age of galaxies. For the case of low mass star cluster, mass of individual stars can grow to that of conventional stars in collision time scale. The requirement of collision time scale being shorter than the Hubble time gives the minimum cluster size. For typical conditions of M31 or M32, the half-mass radii of dark clusters can be as small as 0.1 arcsecond. For the case of clusters composed of stellar remnants, core-collapse and post-collapse expansion are required to take place in longer than Hubble time. Simple estimates reveal that the size of these clusters also can be small enough that no contradiction with observational data exists for the clusters made of white dwarfs or neutron stars. We then considered the possible outcomes of interactions between the black hole and the surrounding stellar system. Under typical conditions of M31 or M32, tidal disruption will occur every $10^3$ to $10^4$ years. We present a simple scenario for the evolution of stellar debris based on basic principles. While the accretion of stellar material could produce large amount of radiation so that the mass-to-light ratio can become too small compared to observational values it is too early to rule out the black hole model because the black hole can consume most of the stellar debris in time scale much shorter than mean time between two successive tidal disruptions. Finally we outline recent effort to simulate the process of tidal disruption and subsequent evolution of the stellar debris numerically using Smoothed Particle Hydrodynamics technique.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.211-221
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• 2014

The study aims to estimate the determinants of policyholder's trust for the Chinese insurance industry by structural equation model. In particular, differences in determinants of trust among Chinese life insurance and auto insurance were derived from the latent mean and multi group analysis. The result shows the most effective determinants of trust were honesty, followed by credibility which shows the compensation ability of insurance company. However, benevolence is not influence statistically on the determinants of trust of both life insurance and auto insurance. Moreover, the policyholder's trust for the insurance industry was later extended to relationship commitment such as renewal and recommendation intentions. Especially, the linkage between the level of trust and relationship commitment was the strongest in life insurance than auto insurance. Even though the result is differ based on types of insurance, in order for the insurance industry to grow stably it is importance to get trust from policyholder.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.1
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• pp.27-31
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• 2000

Characteristics of ethanol production by a xylose-fermenting yeast, Pichia stipitis Y-7124, were studied. The sugar consumption rate and specific growth rate were higher in the glucose-containing medium than in the xylose-containing medium. Specific activities of xylose reductase and xylitol dehydrogenase were higher in the medium with xylose than glucose, suggesting their induction by xylose. Maximum specific growth rate and ethanol yield were achieved at 30 g xylose/L concentration without formation of by-products such as xylitol and acetic acid whereas a maximum ethanol concentration was obtained at 130 g/L xylose. Adding a respiratory inhibitor, rotenone, increased a maximum ethanol concentration by $10\%$ compared with the control experiment. In order to evaluate the pattern of ethanol inhibition on specific growth rate, a kinetic model based on Luong's equations was applied. The relationship between ethanol concentration and specific growth rate was hyperbolic for glucose and parabolic for xylose. A maximum ethanol concentration at which cells did not grow was 33.6 g/L for glucose and 44.7 g/L for xylose.

• The Journal of the Korea Contents Association
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• v.15 no.6
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• pp.247-258
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• 2015

This study is designed to verify structural relations between multicultural family's functions, multicultural family mothers' parental efficacy, and multicultural family children's social competence with the subjects of multicultural family mothers and children. To attain the goal, the researcher collected data through a survey with a self-administered questionnaire conducted to multicultural family mothers and multicultural center workers taking care of multicultural children and utilized 156 sheets for final analysis. According to the study results, multicultural family's functions exert positive effect on multicultural family mothers' parental efficacy, and multicultural family mothers' parental efficacy indicates positive effect on multicultural children's social competence. Also, multicultural family mothers' parental efficacy has completely mediating effect in the relations between multicultural family's functions and multicultural children's social competence. Based on these study results, the researcher suggests ways to intervene with multicultural family mothers and multicultural family in order to help multicultural children grow and develop soundly.

• Journal of Distribution Science
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• v.15 no.11
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• pp.73-82
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• 2017

Purpose - This paper aims to investigate a profit maximizing incentive of foreign traders in distributing the KOSPI 200 Futures. Such an incentive may induce unsophisticated retail traders to suffer loss from speculative trading. Since Korean government increased the entry barriers of the market to protect unsophisticated traders, the market size has been decreasing while the proportion of the contract held by foreign traders has been increasing. These on going changes make the market imperfectly competitive, where a profit maximization incentives of foreign traders are expected to grow. In this paper, we attempt to find any evidence of such behavior, thereby providing implications regarding market policy and market efficiency. Research design, data, and methodology - According to Kyle(1985), an informed trader exploits his/her monopoly power optimally in a dynamic context so that he/she makes positive profit, where he/she could conceal his/her trading utilizing noise trading as camouflage. We apply the KOSPI 200 Futures market to the Kyle's model: foreign traders who take into account the effect of his/her trading to maximize expected profits as an informed trader, retail investors as noise traders, and financial institutions as market makers. To find any evidence of monopolistic behavior, we test the variants of trading volume and price data of the KOSPI 200 Futures over the period of 2009 and 2017. Results - First, we find that the price of the KOSPI 200 Futures are more volatile than the price of underlying asset. Second, we find that monopolistic foreign trader's trading order flows are consistent with exploiting his/her monopoly power to maximize profit. Finally, we find that retail investors' trading order flows are inversely consistent with maximizing profit, that is, uninformed retail investors suffer loss continuously in speculative trading against informed traders. Conclusions - Our results show that the quantity of strategic order flows may have a large effect on the price, therefore, resulting the market inefficiency. The results also imply that, in implementing regulations, the depth of the market must be considered to maintain market liquidity, and suggesting interesting research topics regarding the market structure.

• Journal of Korean Society of Rural Planning
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• v.24 no.3
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• pp.33-42
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• 2018

The aim of our study was to provide a basic data for the development of a small greenhouse model suitable for urban farmers. The study analyzed installation inclination, positive and negative reasons for installation, location of installation, preferred crops in small greenhouses, plans for use of products, and expected effects by using small greenhouse. Positive opinion on small greenhouse installation was 80.4% of the survey respondents. The most positive reason for the installation of small greenhouses was fresh and safe food supply, and the negative reason was maintenance difficulties. The results obtained in our survey indicated that small greenhouses were more likely to be installed near the house, and urban farmers tended to grow organic leafy vegetables in soil. The expected benefits of small greenhouse operation were largely divided into 'benefit for the improvement of the quality of life' and 'benefit for economic profits', and expectation for the improvement of the quality of life was higher than economic benefit. As a result of the Likert 5-point scale analysis, 'benefit for the improvement of the quality of life' by using a small greenhouse was graded as high as 4.17~4.60. On the other hand, the 'benefit to economic profits' was rated as low as 3.51~4.14.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.8
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• pp.1190-1201
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• 2008

The objective of this study is to compare and analyze middle and high school boys' and girls' uniform wearing conditions. The survey was conducted online and data were obtained from 907 middle and high school boys and girls. The results of this study are as follows. First, most boys and girls did not know their body sizes other than their height and weight. Second, when purchasing the school uniforms, over 70% of the boys and girls chose to try on the uniforms before their purchase and over 60% of the boys and girls had trouble selecting their sizes just by reading the labels. Third, both boys and girls considered the fit as the most important factor. When purchasing jackets, both middle and high school boys considered the shoulder width as most important. Middle school girls considered the jacket and sleeve length as most important, whereas high school girls considered the shoulder width, waist, and bust as most important. When purchasing skirts or slacks, waist girth was considered as most important. Fourth, boys repurchased more school uniforms than girls. Boys have outgrown their uniforms usually in the length categories, whereas girls have outgrown in the girth categories. Fifth, more girls(72.7%) modified their uniforms than the boys(56.8%). Boys usually bought bigger uniforms, modified them to fit and when they grow out of their uniforms they planned to modify their uniforms again whereas girls modified their uniforms to follow the trend. Sixth, the online shopping mall survey has revealed that both boys and girls liked the idea of 3D model that reflect their own body shapes, but they had low preference to purchase school uniforms online. Online purchase has been more attractive to the boys than to the girls, while the way of fashioning uniforms has been more attractive to the girls than to the boys.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1892-1903
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• 2016

Mobile social network is becoming more and more popular with respect to the development and popularity of mobile devices and interpersonal sociality. As the amount of social data increases in a great deal and cloud computing techniques become developed, the architecture of mobile social network is evolved into cloud-based that mobile clients send data to the cloud and make data accessible from clients. The data in the cloud should be stored in a secure fashion to protect user privacy and restrict data sharing defined by users. Ciphertext-policy attribute-based encryption (CP-ABE) is currently considered to be a promising security solution for cloud-based mobile social network to encrypt the sensitive data. However, its ciphertext size and decryption time grow linearly with the attribute numbers in the access structure. In order to reduce the computing overhead held by the mobile devices, in this paper we propose a new Outsourcing decryption and Match-then-decrypt CP-ABE algorithm (OM-CP-ABE) which firstly outsources the computation-intensive bilinear pairing operations to a proxy, and secondly performs the decryption test on the attributes set matching access policy in ciphertexts. The experimental performance assessments show the security strength and efficiency of the proposed solution in terms of computation, communication, and storage. Also, our construction is proven to be replayable choosen-ciphertext attacks (RCCA) secure based on the decisional bilinear Diffie-Hellman (DBDH) assumption in the standard model.