• Polymer(Korea)
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• v.32 no.2
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• pp.183-188
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• 2008

Reinforced open cell micro structured foams were prepared by the polymerization of high internal phase emulsions incorporating inorganic thickeners. Organoclays were used as oil phase thickener, and sodium montmorillonite was used as aqueous phase thickener. Rheological properties of emulsions increased as oil phase thickener concentration and agitation speed increased, due to the reduced drop size reflecting both competition between continuous and dispersed phase viscosities and increase of shear force. Drop size variation with thickener concentration could be explained by a dimensional analysis between capillary number and viscosity ratio. Upon the foams polymerized by the emulsions, compression properties, such as crush strength and Young's modulus were measured and compared. Among the microcellular foams, the foam incorporated with an organoclay having reactive group showed outstanding properties. It is speculated that the exfoliated silicate layers inside polystyrene matrix, resulting in nanocomposite foam, are the main reason why this foam has enhanced properties.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.688-692
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• 2005

Importance of substitute energy has been increasing due to environmental issues and lack of fossil fuels. In addition, heating cost that occupies from 30 to $40\%$ of the total production cost in Korean protected cultivation needs to be reduced for profitability and global competition. But, studying on substitute energy to solve these problems has not been activated for Korean protected cultivation. Therefore, this study was conducted to develop a geothermal heat pump system for cool ing and heat ing of greenhouses at a lower cost than conventional hot air heater and air conditioner. Fundamental test of heat transfer characteristics in soil was conducted by computer simulation and controlled tests for its verification. Based on the results of the theoretical and empirical investigations, an optimum heat pump system was developed and the performance was evaluated for practical use in a greenhouse at the Pusan Horticultural Experiment Station. The system was compared with a conventional hot air heating system through a cucumber growing test and economic feasibility analysis. Results of the application test of the geothermal heat pump showed that with an initial setting of $15^{\circ}C$ the inside temperature of the greenhouse could be maintained between 15 and $17^{\circ}C$. Results of the cucumber growing test showed that there were no significant differences in average height, leaf length, leaf width, number of nods, leaf area, dry weight and yield between the plots wi th the geothermal heat pump system and a conventional hot air heater. Economic feasibility analysis indicated that the variable cost of the hot air heater could be saved $81.2\%$ using the geothermal heat pump system. It was concluded that the geothermal heat pump system might be a pertinent heating and cooling system for greenhouses because of the low operating cost and the use of environment-friendly geothermal energy.

• Journal of Korean Society of Transportation
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• v.20 no.2
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• pp.7-16
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• 2002

Rapid growth rate of container traffic in China has caused the fierce competition to attract Trans-shipment Container Cargos from/to China among competitive ports in Asia. Therefore, this paper aims to suggest some strategies to attract them from/to China by Korea ports. To do so, it evaluates the preference of important ports in the competitive situation and the competitiveness of important ports in Asia, and finally proposes the relative order of important factors. Based on the evaluation of it, Both the Pusan and the Kwangyang ports have to strengthen port facility to attract move traffic and in detail, reinforce the number of berth, yard areas and handling equipment. they also have to provide high qualify of services to deliver cargos in time. not being damaged and swiftly response to shipowner and shipper's claim.

• Journal of Technology Innovation
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• v.26 no.3
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• pp.1-36
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• 2018

In the era of the 4th Industrial Revolution, it is important for companies to understand the changing environment by converging various technologies and to respond to the changing business environment. In this study, we conducted a social network analysis on 10 firms in the automotive industry, which have recently been accelerating their competition for technology development, by extracting convergence patents co-classified in two or more of the US registered patents in the last 6 years. As a result, it has been confirmed that the number of technology related to the convergence of the automotive field is greatly increasing, and the convergence between the technologies is becoming stronger. In addition, Volkswagen, Ford and Hyundai showed significant changes in technology convergence. They were analyzed as having a change in strategy in eco-friendly automotive technologies. This study suggests various ways for companies to utilize the results of network analysis more meaningfully.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3804-3814
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• 2009

Because of the stagnancy of business activity and an excessive competition, the number of the people who quitting of one's business is increasing rapidly. Especially, government is further efforts on the upbringing for the small and micro business. But the ratio of cessation of business is increased gradually due to the influence of saturated market, consumer confidence shrinking, lack of funding and appearance of super supermarket. The another characteristic of growth rate for the cessation of business is the increase of the second foundation of business desire to succeed. But government's business transformation policy is inadequate. So, this study is willing to give an improvement of the government's support system through extraction actually and dependable data about business transformation and analysis to found a various gain model that continuous growth in small and micro business.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.15 no.4
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• pp.117-130
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• 2007

Incheon International Airport has handled 3,054,485 transfer passengers (11.9% transfer rate) and 950,441 transfer cargo(44.2% transfer rate)recorded in 2005. Comparing to 30-40% transfer passenger rate which are competition hub airports in northeast Asia, transfer passenger rate of Incheon International Airport is lower. Above all, We think that Minimum Connecting Time(MCT) which is relating factors with transfer rate need to be monitored to make up for the weak points in the current Incheon internationalairport system. Minimum Connecting Time is defined the legally minimum time necessary to change planes at a given airport. and Transfers represent 35% of the total passenger volume at Vienna International Airport in Europe, which underscores our function as a major international hub. Vienna is rated priority in reservation systems because of our excellent minimum connecting time, and that increases the sale of tickets through our airport. In 2004 the total number of transfer passengers rose 18% to 5,089,624. Short routes, a one roof concept and an outstanding logistics system make Vienna an ideal airport for transfers. This transfer-friendly one roof concept will also form the basis for the new VlE-Skylink Terminal. In case of Japan, Star Alliance has also implemented its so called "Move under one roof"concept at the new Centrair airport. All member carriers are located in the same part of the termina1, sharing check-in counters and ticketing facilities. Star Alliance member carriers can now offer customersa reduced average minimum connecting time of one hour, for transfers between international and domestic. The research purpose of the Study on the Enhancement for Minimum Connecting Time of Incheon International Airport is to increase transfer rate of passenger and cargo of Incheon International Airport at Northeast Asia through this paper.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.4
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• pp.64-73
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• 1999

This study was conducted to find out the effects of hydroseeding material and seed mixture on the revegetation of rock cut-slopes by PEC4 (Polymer-Ecology-Control) Hydroseeding Measures. PEC4 hydroseeding material was applied to four cut-slopes using hydroseeding measures from April to August, 1999, and the field survey was carried out by monthly. PEC4 material consisted of bark compost and organic soil amendments. This material has high content of organic matter and high level of water holding capacity. PEC4 hydroseeding material shows low level of soil hardness, so it gives to good condition for seed germinating and plant growing in early stage. PEC4 material attached at rock cut-slopes by two types of adhesive agent was not eroded by rainfall. The plant coverage and number of plant species were affected by mixing ratio of seeds and seeding timing. From the viewpoint of plant establishment, the optimal hydroseeding timing of mixed seeds for plant growth seems to be in May. Most of the plant seeds were germinated well and they covered rock cut-slopes so quickly and effectively. Plant importance value of Silene armeria and Platycodon grandiflorum. were higher than any other seeded-native species in the competition between native species and exotic species, so they have enough possibility to be used for slope revegetation works. Thus it leads to conclusion that the revegetation method used in this experiment was a very effective method for plant establishment on rock cut-slopes.

• The International Journal of Costume Culture
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• v.2 no.1
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• pp.31-42
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• 1999

The category killer that has been rapidly growing mainly in advanced countries since early 1990's, is a mew distribution model which aims for obtaining market controlling power by surpassing competing businesses in a specific area of products. The domestic situation of category killers is very different from that of advanced ones abroad since it has just been introduced into the Korean market. At the moment, there are only 10 or so companies operating in the market : Geopyung's , Taeheng's , Midopa's , of Sinsegye Department store, adn of Yerim International. The purpose of this study is to examine problems of domestic companies in the present market by analysing the operation status of category killers in domestic markets as well as foreign ones, and to suggest a counter-strategy of category killers for the distribution environment of the 21st century to improve the competitiveness of Korean distribution industry. The competitiveness of category killers lies above all in products lines. Category killers are equipped with the greatest number of products lines among those of competing businesses due to maximized product selections in an limited range. Another source of competitiveness may be found in balanced strategy positioning. That is to say, category killers are in a position where they can adjust policies towards any of the three purposes while aiming at them altogether : prices of discount stores, products range of specialty stores, and customer service level of department stores. It is also necessary for efficient store operation to use information technology such as electronic data interchange (EDI), electronic pose system(EPOS) and electronic funds transfer (EFTPOS). As for the cost structure, category killers can gain an advantage over other business since operating cost of various sections can be saved. There are, however, certain risks that category killers with strong competitiveness may influence on other businesses a great deal and even facilitate their decline. Yet it seems that the growth of category killers will be more viciously restrained by continuous challenges from other businesses. The distribution industry is supposed to develop through such competition and restraint.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.455-461
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• 2015

while the mobile game is the publishing of KakaoTalk, mobile game industry, became the opportunity for more growth. However, after two years in service, this time in a number of games has a service Kakaogame, but out Profitable game is out steadily, as compared to the service game was in early Kakaogame many I was reduced. Everyone hurried game of in feature If you get a good game is depending of course also Profitable model. Although domestic mobile game is a lot of publishing of KakaoTalk, in order to the competition between the same kind of game because it is similar to everyone game, profit structure in the game is important. Under the paper to find a direction that can be maximized through the previous study the benefits of typical Profitable model used Kakaogame has been presented in the direction of a new Profitable model.

• Journal of the Korean Society for Library and Information Science
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• v.50 no.1
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• pp.513-532
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• 2016

The purpose of this study is to gain a better understanding of undergraduate citation behavior and to measure the contribution which an academic library makes in the academic writing of students. Citations in 80 student papers submitted in the academic paper competition was analyzed for types of items cited and the number of items in the library collection, etc. The findings indicate: 1) the level of undergraduates' citation knowledge is very low, 2) undergraduates prefer web resources (44.9%) to such academic resources as books, journal articles, theses or dissertation, and 3) undergraduates find academic resources in their academic library. Upon these findings, this study suggests that academic library staff should intervene to enhance undergraduate academic writing skills and to develope of educational material, including how to search for and cite reliable resources.