• Journal of the Korea Society of Computer and Information
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• v.16 no.7
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• pp.137-148
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• 2011

Different from the traditional client-server model, it is possible for participants in a cooperative distributed system to get quality services regardless of the number of participants in the system since they voluntarily pool or share their resources in order to achieve their common goal. However, some selfish participants try to avoid providing their resources while still enjoying the benefits offered by the system, which is termed free-riding. The results of free-riding in cooperative distributed systems lead to system collapse because the system capacity (per participant) decreases as the number of free-riders increases, widely known as the tragedy of commons. As a consequence, designing an efficient incentive mechanism to prevent free-riding is mandatory for a successful cooperative distributed system. Because of the importance of incentive mechanisms in cooperative distributed system, a myriad of incentives mechanisms have been proposed without a standard for performance evaluation. This paper draws general incentive design considerations which can be used as performance metrics through an extensive survey on this literature, providing future researchers with guidelines for the effective incentive design in cooperative distributed systems.

• Journal of Digital Convergence
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• v.17 no.12
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• pp.467-472
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• 2019

Growing smartphone usage in South Korea has also accelerated the pace of development of mobile games, but competition is intensifying as the market grows. As one of the factors for the success of the game in this mobile game market, UI has been presented, suggesting that the design of such mobile game UI should be approached in terms of designing the user's experience, along with its function, aesthetic expression, function-oriented design and information delivery before. In this paper, we propose an effective lobby layout of mobile RPG using experience among UX factors. Through the layout classification of Ernest Adams and Andrew Rollings, we selected 9 mobile RPGs in the 20th place of google play cumulative sales rankings and analyzed the layout of the lobby. As a result, the lobby layout of the game, which led the first market success of the mobile RPG genre, The result was that it became the standard of the boxed game. It can be interpreted that the lobby layout, which is similar to the game used previously by the user, is effective because low entry barriers and learning are unnecessary due to the experience of using the existing RPG. Future studies may produce a common layout of a broad genre if studies are conducted to measure the optimum UX for other genres than RPG.

• The Korean Journal of Mycology
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• v.22 no.1
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• pp.8-30
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• 1994

The synthesis of phospholipids and the composition of fatty acids were analyzed in the fungal cells of Aspergillus phoenicis, Rhizopus acidus and Candida albicans treated with carbon sources (glucose, sucrose, raffinose) during the culture. Growth ratios were predominantly in Aspergillus and Candida treated with sucrose and those in Rhizopus treated with glucose. The synthesis of total lipids were accelerated in Aspergillus and Rhizopus with glucose and the contents of total lipid was increased in Candida with raffinose. The glucose treatment increased Phosphatidylinositol(PI) content by 73.7% for Aspergillus and Phosphatidylcholine(PC) content by 292% for Rhizopus. In sucrose treatment the synthesis of PI was accelerated 112% for Aspergillus and that of PC was increased 77.7% for Rhizopus and 71.8% for Candida. In raffinose treatment, the content of PC was increased 79.5% for Aspergillus, the biosynthesis of Phosphatidylethanolamine(PE) was inhanced 50.9% for Rhizopus and 49.1% for Candida. In Aspergillus and Candida, oleic acid and linoleic acid were major fatty acids for biosynthesis of PC and PE when the three carbon sources were treated. The major fatty acids for biosynthesis of phospholipid was palmitic acid and linoleic acid in Aspergillus, palmitic acid in Rhizopus and oleic acid in Candida. Palmitic acid was one of major fatty acids utilized for the biosynthesis of phospholipid(PC, PE, PI) in the fungal cells treated with carbohydrates.

• Science of Emotion and Sensibility
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• v.12 no.2
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• pp.225-232
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• 2009

There are life-style and many different cultural differences between countries. Among them, food is different from other areas. Especially, if Food Tools are used by food type, even though the design factor is same, the function is different. Therefore, research and development of a Food Tool design is necessary to use a Universal Food Tool between countries. The purpose of this research is to develop a behavior analysis process for food, finding similarities and differences by food type; and cultural differences between countries; and to propose a design Food Tool design that can be used between countries. This research on methods and content is for the development of the consumer behavior analysis process about food, grafting theoretical studies about behavior analysis and working behavior analysis on the spot, to develop a food action analysis process. Second, do comparative analysis process of food order and evaluation between countries; and think about the problems and symptoms, then propose methods to resolve the problems. Third, each process is divided by category, to find the features by each category of foods between countries. Results may be obtained through research and the comparative analysis of each country's, foods, behavior and restaurant types. Specifically, researchers can use food tool design to obtain results and compare the same items between countries, compare university design education, and create new ideas through cooperation and complementary research.

• Economic and Environmental Geology
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• v.24 no.3
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• pp.233-244
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• 1991

A biotite that substantially altered to chlorite and vermiculite in hornblende gneiss from Cheonyang, Korea, has been investigated with electron microprobe analysis. The data show the general variational trends of Ti and K-leaching with increased weathering. However, the chloritization is characterized by Si- conservative reaction and relatively dramatic increase of Al-for-(Fe+Mg) octahedral substitution, whereas the vermiculitization is characterized by total Mg-conservative and Ca-enriching exchange reaction. In the initiating stage the vermiculitization proceeded in a continuous decrease of the Al-for-Si tetrahedral substitution and an increase of the Al-for-(Fe+Mg) octahedral substitution, supporting the currently accepted weathering process. But it differs in the late stage, in which AI(IV) and Fe increase significantly. Recalculations of the structural formular for vermiculite on the basis of several assumptions indicate that the oxidation of Fe is necessary for vermiculite to form the reasonable strutural formular. The relative timing of the oxidation of Fe probably occurs in the late stage, supported by the substantial increase of the Al-for-Si tetrahedral substitution.

• Journal of KIISE:Software and Applications
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• v.27 no.1
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• pp.50-61
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• 2000

Recently the stereo vision based on conics has received much attention by many authors. Conics have many features such as their matrix expression, efficient correspondence checking, abundance of conical shapes in real world. Extensions to higher algebraic curves met with limited success. Although irreducible algebraic curves are rather rare in the real world, lines and conics are abundant whose products provide good examples of higher algebraic curves. We consider plane algebraic curves of an arbitrary degree $n{\geq}2$ with a fully calibrated stereo system. We present closed form solutions to both correspondence and reconstruction problems. Let $f_1,\;f_2,\;{\pi}$ be image curves and plane and $VC_P(g)$ the cone with generator (plane) curve g and vertex P. Then the relation $VC_{O1}(f_1)\;=\;VC_{O1}(VC_{O2}(f_2)\;∩\;{\pi})$ gives polynomial equations in the coefficient $d_1,\;d_2,\;d_3$ of the plane ${\pi}$. After some manipulations, we get an extremely simple polynomial equation in a single variable whose unique real positive root plays the key role. It is then followed by evaluating $O(n^2)$ polynomials of a single variable at the root. It is in contrast to the past works which usually involve a simultaneous system of multivariate polynomial equations. We checked our algorithm using synthetic as well as real world images.

• Korea journal of population studies
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• v.31 no.1
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• pp.99-125
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• 2008

This article aimed to clear that the systematic bias according to the length of work time exists between estimated work time by self-reported questions used mainly in measuring and calculating the length of work time because of strong points of easy in measuring and so on and diary work time by time-diary method used because of the strong point that can measure more accurate lifetime by recording various activities of respondents during 24 hours in the stream. As the result that analyze the data from Lifetime Use Survey in 2004, the result like the contradiction came that the tendency of overstating work time is rising according as estimated work time increases via estimated work time, whereas the tendency of understating work time is rising according as diary work time increases via diary work time. The reason that the opposite results come despite the data from the same survey is that random errors act in the opposite directions by regression to the mean. Therefore, we cannot emphasize that a man working long hours tends to exaggerate his work hours by the result via estimated work time. That is, the fact that the systematic bias by the increase of work time does not exist is confirmed, and therefore, it is also impossible to raise questions about the accuracy of the data through estimated work time by self-reported questions from the evidence of the existence of that bias.

• Land and Housing Review
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• v.4 no.3
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• pp.259-270
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• 2013

This paper defined the concept of unsold land and diagnosed the cause of unsold land of LH business site. The results are showing as follows. First, unsold land is defined as land could not be sold until the completion of the project, and plan to sell the unsold land can be changed partially. Second, the status of unsold land in the 226 project sites were analyzed. $146km^2$ area corresponding to 74.8% of the total capital area($195km^2$) are unsold. By purpose, co-residential($38km^2$), industry($21km^2$), exclusive residential($16.4km^2$), commercial business($12.5km^2$), education($10.2km^2$) was larger in order. Third, value enhancement target project sites were selected and its symptoms and the cause of unsold land were analyzed. For the project site over average unsold rate, 6 sites located in province and 2 sites located in capital region were selected through collecting the practitioners and expert opinion. These 8 sites are characterized that sale of land for medium and large co-residential, urban support facilities, block-shaped house and attached house was inactive. Also, these sites commonly experienced economic fluctuations, changes in market demand, supply and demand mismatch, inflexible planning standards.

• Journal of Gifted/Talented Education
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• v.23 no.3
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• pp.453-477
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• 2013

The intent of this study is to fully investigate the major issues and challenges related to characteristics of gifted children from multicultural families in Korea. The gifted students of multicultural families are currently categorized as disadvantaged gifted students, but they need to be defined more deeply and separately due to the continuous increase of multicultural families. Most culturally different gifted children have common problem such as integrating into Korean culture, often suffering from emotional problems and their parents' economic disadvantage. Due to these problems a variety of issues arise. First, culturally diverse talented students have problems due to the alienation and the lack of equal opportunity given to gifted children of multicultural families in need. Secondly, another issue is whether or not the selection of these students for a gifted and talented program is administered equally and fairly. Thirdly students and teachers may have difficulty forming relationships. Fourth, there is a dire need to address the issue of a lack of formal education policy. for these students. Fifth, the formulation of a gifted and talented program solely for multicultural students is necessary. Sixth, educating the parents of such students remains a critical challenge. Seventh, the last issue arises from a lack of research regarding the identity of multicultural gifted children in Korea. In this study, we discuss each of these issues in-depth. Additionally the future of Korean Multicultural Gifted selection, training in the field, school direction and it's implications are discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.560-566
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• 1998

The bacteriocin produced by Lactobacillus sp. GM7311 showed strong inhibitory activity against the growth of three Gram positive bacteria, Listeria monocytogenes, Bacillus subtilis, and Staphylococcus aureus. When the bacteriocin was added to the culture at different phases, viable cells of all of the tested strains were decreased, although the most inhibited phase was different. Thereby, when the bacteriocin $(100\;Bu/m{\ell})$ was added to exponential and stationary phase of L. monocytogenes, the rapid reduction of viable cell counts occured. And, in the case of B. subtilis, the highest inhibitory effect occured at lag phase and mid-exponential phase by the addition of the bacteriocin under same condition as mentioned above. Also, we can observe the accelerated reduction of survivors counts for the all of the phase except stationary phase in the S. auresus. Transmission electron microscopic observation of L. monocrogenes and B. subtilis treated with bacteriocin revealed apparent Iysis of the cell wall and excretion of the cell contents, indicating bacteriolysis. Also, the amino acids and fatty acids compositions were different from controls. However, the Iysis of cell wall didn't occur in S. aureus, though the cytoplasmic materials were reduced. This result indicates that the bacteriocin inhibits the synthesis of nuclear materials such as DNA, RNA and proteins.