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Design of Bluetooth based MMORPG Game in MANETs (모바일 애드-혹 망에서 Bluetooth 기반 MMORPG의 설계)

  • Oh, Sun-Jin
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.4
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    • pp.39-45
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    • 2009
  • With the rapid growth of recent wireless mobile computing application technology and handheld mobile terminal device development technology, one of the big issue in these fields is to design online games in wireless mobile ad hoc network environment. Online games in mobile computing environment have lots of constraints for developing online games because mobile terminals have many limitations such as low performance of processor, limited memory space, small bandwidth of wireless communication, and confined life of battery power. Therefore, most of mobile games are restrictive in the function of online and multi-play up to date. In this paper, the online MMORPG game, capable of multi-play with many other mobile users using mobile terminals in wireless mobile computing environment, is designed and implemented. Proposed mobile online game uses bluetooth to construct temporary wireless mobile ad hoc network with other mobile clients, and designed to carry out online MMORPG game with these clients. It also supports multi-play among them.

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Surface Analysis of Fluorine-Plasma Etched Y-Si-Al-O-N Oxynitride Glasses

  • Lee, Jung-Ki;Hwang, Seong-Jin;Lee, Sung-Min;Kim, Hyung-Sun
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2009.05a
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    • pp.38.1-38.1
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    • 2009
  • Plasma etching is an essential process for electronic device industries and the particulate contamination during plasma etching has been interested as a big issue for the yield of productivity. The oxynitride glasses have a merit to prevent particulate contamination due to their amorphous structure and plasma etching resistance. The YSiAlON oxynitride glasses with increasing nitrogen content were manufactured. Each oxynitride glasses were fluorine-plasma etched and their plasma etching rate and surface roughness were compared with reference materials such as sapphire, alumina and quartz. The reinforcement mechanism of plasma etching resistance of the YSiAlON glasses studied by depth profiling at plasma etched surface using electron spectroscopy for chemical analysis. The plasma etching rate decreased with nitrogen content and there was no selective etching at the plasma etched surface of the oxynitride glasses. The concentration of silicon was very low due to the generation of SiF4 very volatile byproduct and the concentration of aluminum and yttrium was relatively constant. The elimination of silicon atoms during plasma etching was reduced with increasing nitrogen content because the content of the nitrogen was constant. And besides, the concentration of oxygen was very low on the plasma etched surface. From the study, the plasma etching resistance of the glasses may be improved by the generation of nitrogen related structural groups and those are proved by chemical composition analysis at plasma etched surface of the YSiAlON oxynitride glasses.

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Insect Funa of Chestnut Bushes at Paju Area in Korea: -Mainly on Dryocosmus kuriphilus Yasumatsu-

  • Pak, Nomyon
    • The Korean Journal of Zoology
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    • v.13 no.1
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    • pp.3-8
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    • 1970
  • 1. Paju area of Kyonggydo has received serious damages by Dryocosmus kuriphilus Yasumatsu in the bushes of Castanea crenata S. et Z. since 1965. I have also found the middle parts of whole country of Korea has damaged by this wasp. 2. Bobwonri was the worst case in its damage by Dryocosmus kuriphilus Yasumatsu with most prosperous parasite, Aletia flavostigma singularis Butler and Dictyoploca japonica Moore. I conclude that this is the result of the lack of beneficial insects and isolated bush formation. 3. The chestnut bush at Bunsuri was recovering from the damage of gall wasp nevertheless it was illustrated big damage at last year's hranches. I conclude that this recovering phenomena is closely related with the insect fauna of this area and this characteristic insect fauna was derived from the bush formation which reveals specific bush arrangement that can be illustrated as surrounded by another bush of Quercus acutissima Carruthers. 4. As a final conclusion, I recommend mixed bush formation of chestnut tree with Quercus species to control insect population dynamics in healthy status.

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A Study on Dyeing Properties and Color Research of Knitted Fabric and by Scoria

  • Chung, In-Hee
    • Journal of Fashion Business
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    • v.11 no.3
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    • pp.79-86
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    • 2007
  • The purpose of this study is to understand the dyeing properties and color analysis of fabrics knitted with ramie, cotton, wool and acrylic by using scoria and to analyze whether the knitted fabrics can be used for industrialization by measuring color fastness after and before sliver-nano process. The following is the conclusions. Firstly, when ramie fabric regarding cotton, wool and acrylic was dyed at the temperature of $50^{\circ}C$ for fifteen minutes by using 10, 25, 50, 100g/ $\ell$ of scoria, dyeing absorption gradually increased up to 50g/ $\ell$, and over the point of 50g/ $\ell$ it showed slow increase. Secondly, regarding saturation, among ramie fabric, wool, cotton and acrylic, wool appears as the lowest brightness. Therefore, it can be dyed with bright color and the highest value. In terms of the value of chromaticity, wool also emerges as the lowest brightness. On the contrary, acrylic showed the lightest red as it had the value of the smallest b. Cotton takes the lightest yellow as the b value of the cotton showed the smallest. Thus, scoria dyestuff is a material that showed strong red and yellow on knitted fabric mixed with wool that is the biggest a. b value. Thirdly, in terms of dyeing fastness, sunlight fastness did not show noticeable differences before and after silver-nano processes, but in terms of washing and friction fastness, the material processed by silver-nano indicated that all knitted fabrics are over 4-5 point. which means silver-nano process can be effective for the industrial applications. As mentioned above, as a result of dyeing knitted fabrics with scoria, this study found a possibility of dyeing in the fabric materials, and if there is deeper dyeing experiments, fastness experiments and speculations, it might be possible to be a big issue just like loess and charcoal.

A Study on Prediction of Aircraft Noise in Tae-an Airfield (항공기소음예측에 관한 연구;태안비행장 중심으로)

  • Kim, D.H.;Park, S.B.;Song, B.H.
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.13 no.3
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    • pp.73-84
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    • 2005
  • Hanseo University's Tae-an Airfield was opened in July, 2005 for aeronautical education such as aircraft flight, air traffic control, avionics, etc., and will play an important part as a base for local economic and industrial developments. On the contrary, the aircraft noise from the airfield will give an impact against the vicinity of the airfield and become a big issue which the airfield authority has to solve. The aim of this study is to analyse the aircraft noise contour in vicinity of the airfield and to make understand the people around the airfield how much the aircraft noise will have an effect on. For the prediction of the aircraft noise in the local area, this study showed the method to assess the aircraft noise in the developed countries for aviation, and the result to compute WECPNL by INM 6.1 after encoding the various data including environmental input data, tract, and profile. The major results of the study can be summarized as follows ; While the area with influence contour of noise from 75 to 80 WECPNL is 0.555$km^2$, the area from 80 to 85 is 0.343$km^2$, and the area with influence contour of noise over 85 WECPNL is 0.163$km^2$. In addition, there are 4 houses in the contour over 85 WECPNL and the inhabitants(10 people) in this area will have effect from the noise. Therefore Tae-an airfeild authority is preparing the noise-prevention method or noise abatement program. Finally, according to the noise contour, it is one of the best way of decreasing the effect of aircraft noise that 33 runway is assigned as calm-wind runway because there is no resident in the area around 15 threshold.

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Development of Core Technologies of Multi-tasking Machine Tools for Machining Highly Precision Large Parts (고정밀 대형 부품가공용 복합가공기 원천기술 개발)

  • Jang, Sung-Hyun;Choi, Young-Hyu;Kim, Soo-Tae;An, Ho-Sang;Choi, Hag-Bong;Hong, Jong-Seung
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.2
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    • pp.129-138
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    • 2012
  • In this study, three types of large scale multi-tasking machine tools together with core technologies involved have been developed and introduced; a multi-tasking machine tool for large scale marine engine crankshafts, a multi-tasking vertical lathe for windmill parts, and a large scale 5-axis machine tool of gantry type. Several special purpose devices has been necessarily developed for the purpose of handling and machining big and heavy workpieces accurately, such as PTD (Pin Turning Device) with revolving ring spindle for machining eccentric crankshaft pins, hydrostatic rotary table and steady rest for supporting and resting heavy workpieces, and 2-axis automatic swiveling head for high-quality free surface machining. Core technologies have been also developed and adopted on their detail design stage; 1) structural design optimization with FEM structural analysis, 2) theoretical hydrostatic analysis for the PTD and rotary table bearings, 3) box-in-box type cross-rail and octagonal ram design to secure machine rigidity and accuracy, 4) constant spindle rpm control against gravitational torque due to unbalanced workpiece.

A Study on the Determinants of Residential Satisfaction of Lease Apartment - Focusing on Lease Apartment and the Apartment converted into Installment Sale - (임대아파트 입주가구의 주거만족도 결정요인에 관한 연구 - 임대아파트와 분양전환아파트를 중심으로 -)

  • 이중근
    • Journal of the Korean housing association
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    • v.14 no.4
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    • pp.109-119
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    • 2003
  • This paper has examined a resident's feeling of satisfaction on residential environment. It has searched a policy direction to improve the quality of residential environment with three models in which what factors have an influence on the resident's feeling of satisfaction is evaluated. First, when the residents were asked why they chose lease APT, Low price was answered the most between two populations. Second, with regard to the feeling of satisfaction by categories, both populations showed similar results. The social prejudice on lease APT such as disadvantage on their children and unfavorable surroundings that has been engraved in people's mind about lease APT for a long time was never an issue any more. Third, when the two populations were examined by regression analysis with three models in terms of what factors had an effect on the feeling of satisfaction, there was no big difference in each effect of variables. Internal environment was a key variable for lease APT while external environment was a core variable for the APT that is converted into installment sale. In order to enhance the feeling of satisfaction on residential environment for lease APT residents, high quality turned out the most important factor between both populations, and then a loan with low interest rate and high average standard of APT followed. As unsatisfactory items, low cultural level, slowness in repairing works, and unsatisfactory finishing work were pointed out with regard to the low quality of internal facilities. In general, it turned out that the APT that was converted into installment sale was more preferable than lease APT. As known in this analysis, housing supply policy needs to be focused on quality and high average standard of APT should be achieved for the working classes.

A Study on Visiting Nurses' Perception of the Service Referral between Health and Welfare (보건 및 복지영역 서비스 연계에 대한 방문간호사의 인식)

  • 정문희;유인영
    • Korean Journal of Health Education and Promotion
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    • v.19 no.2
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    • pp.155-167
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    • 2002
  • This study was carried out to grasp visiting nurses' perception of the service referral between health and welfare with a view to providing the basic data for the visiting nursing activities. A questionnaire survey was conducted on public health nurses in 25 health centers in Seoul from Feb. 12, 2001 to Mar. 15, 2001. A total of 151 questionnaires were collected and they were analysed by use of SPSS/WIN 7.5. The results of the survey are as follows. 1. In general, visiting nurses were burdened with heavy workloads. On average, a visiting nurse covered 5 ‘dong's(the smallest administrative unit), 564 households, and 1223 persons. They spent almost a quarter of their working hours moving from home to home and recording the charts after home visiting. They took 30-60 minutes to provide their services when visiting homes. As for the frequency of home visiting, they were following the instructions recommended by the government. However, their services were still wasteful, not skill-oriented, in that they spent more time assessing ‘subjects’ rather than providing their ‘services’ for them. 2. As for the degree of service performance, visiting nurses scored average 2.94 and 2.28 on the four-point scale in the area of health and welfare respectively. The Pearson coefficient between the two variables was high(.56). According as the health services increased, the welfare services increased as well, which showed that the service referral between the two areas should be essential. 3. ‘The necessity of cooperation with social welfare staff’ scored average 4.49, and ‘the degree of cooperation with social welfare staff’ scored average 3.16 on the five-point scale; There was a statistically significant difference (average 1.33) between the two variables. Such a big difference between perception and practice results from the lack of political support that connects the two service areas comprehensively. Therefore it is recommendable to establish a so-called ‘Visiting Nursing Center’ in the ‘dong’ office in order to provide integrated services of health and welfare at once in cooperation with social welfare staff. That's the way to meet the public needs directly and it's more efficient as well in terms of cost-saving.

Everyday Life Culture, Housing Importance and Housing Satisfaction of Older Korean-Chinese Living in Harbin, China (할빈 거주 조선족 노인의 생활문화, 주거중요도와 주거만족도)

  • Hong, Hyung-Ock
    • Journal of Families and Better Life
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    • v.30 no.5
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    • pp.29-47
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    • 2012
  • The purpose of this research is to identify the everyday life culture, housing satisfaction and housing importance of older Korean-Chinese living in Harbin, China. Social survey research using the questionnaire was conducted from August to October in 2011. A total of 94 usable samples were analyzed by the SPSS version the 18.0 statistical program using frequency, percentage, cross-tabulation, factor analysis, and Pearson's correlation. The major findings were as follows. Firstly, older Chinese in Harbin were assimilated into Chinese culture such as national holidays and respectful people, but acculturated in terms of their daily food, and their preference to live in a Korean-Chinese village. Secondly, they had mainly lived in multi-story houses, the so called Chinese-style apartments. The average size of their living space was $80.33m^2$ and they were usually unsatisfied with their neighbors and floor treatment lacking Ondol(溫突). Thirdly, 5 factors affecting on housing value orientation were 'physical characteristics','emotional characteristics', 'economic characteristics', 'social characteristics', 'neighbor characteristics/reputation of the house' and they explained 73.9%. 2 factors affecting on housing satisfaction were 'inner complex/inner space' and 'neighborhood environment' and they explained 69.4%. In conclusion, some policy is needed for Korean Chinese living in Harbin for their well-being when it comes to their housing needs and conditions. Given the nature of big city, Harbin and its attraction, younger Korean-Chinese tend to be rapidly assimilated into Chinese culture. However older people in Harbin think that it is important for their children to learn both countries' languages and cultures in order to be successful, so some concrete policies and supports are needed.

A Study on Inequality Analysis of Academic Information Sharing in University Libraries using Gini's Coefficient and Pareto Ratio (지니계수와 파레토 비율을 활용한 학술정보공유 기여에 대한 대학도서관 격차 분석)

  • Cho, Jane
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.31 no.1
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    • pp.237-255
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    • 2020
  • Pareto principle states that, for many events, roughly 80% of the effects come from 20% of the causes. This study clarified if there is Pareto principle in Korean universities' academic information resource sharing network and calculates the Gini efficient about inequality in sharing academic resources. As a result, top 20% libraries led 80% of performance and inequality degree showed 0.8 as very serious condition. Relative Gini efficient which is recalculated considering scale of each libraries stay 0.7 that is adjusted slightly down. It means that such phenomenon is not caused by the difference of each universities scale with high contribution of big university and low contribution of small university. And in comparison of inequality between university's types, inequality between community colleges and private universities is more serious than four-year-course college and national university respectfully. Finally, as a result of visualizing the distribution of participating libraries, there were libraries with overwhelming contributions, and libraries with small but relatively high contribution levels were also distributed.