• Title/Summary/Keyword: 협력적

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Secure Cluster Head Elections Based on Trust for Wireless Sensor Networks (무선 센서 네트워크를 위한 신뢰 기반의 안전한 클러스터 헤드 선출)

  • Wang, Gicheol;Cho, Gihwan
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.10
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    • pp.50-64
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    • 2013
  • In clustered sensor networks, since a CH (Cluster Head) collects data from its members and delivers the collected data to the sink, it is very important to prevent compromised nodes from joining a CH election and manipulating and fabricating the election result. In order to protect CH elections from compromised nodes, unpredictability, non-manipulability, and agreement property should be guaranteed in CH elections. However, existing CH election schemes cannot prevent intelligent compromised nodes from skilfully violating those properties via their cooperation. In this paper, we propose a scheme which protects the CH election process by detecting intelligent compromised nodes and excluding them. For every CH election round, each member gives a direct trust value to other members according to their behavior. Then a real reputation value is given to each member by combining the direct trust value and indirect trust values provided by other members. Then, each node evaluates the real reputation values of members in its cluster and excludes some untrustable nodes from CH candidates. The scheme greatly improves the non-manipulability and agreement property of CH election results compared to other rival schemes. Furthermore, the scheme preserves the high non-manipulability and the high agreement property even in an environment where message losses can happen.

Atmospheric Pollutant Concentrations under the Influences of Internal Gravity Wave and Sea-Land Breeze Circulations in the Mountainous Coastal Regions (산악연안지역에서 내부중력파와 해륙풍순환 영향하의 대기오염농도)

  • Hyo Choi;Joon Choi
    • International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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    • v.23 no.1
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    • pp.18-33
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    • 1995
  • Under the synoptic scale strong westerly winds flowing over the large steep mountains in the eastern coastal region, the strong downslope wind storms such as internal gravity waves should be generated in the lee-side of mountain. Int he daytime as sea breeze circulation induced by meso-scale thermal forcing from sea toward inland confines to the offshore side of coastal sites due to the eastward internal gravity waves. Thus, surface winds near the coastal seas were relatively weaker than those in the open sea or the inland sites. Evidently, two different kinds of atmospheric circulations such as an internal gravity wave circulation with westerly wind and a sea breeze circulation with both easterly wind near the sea surface and westerly in the upper level were apparently produced. Under this situation the atmospheric pollutants at Kangnung city should be trapped by two different circulations in the opposite directions and resulted in the high concentrations of Total Suspended Particles (TSP) and ozone (O3). At night a meso-scale land breeze from land toward the more intensification of westerly winds in the coastal regions. The concentrations of TSP controled by the strong surface winds blowing from the mountain side toward the coastal sea were relatively higher at night than those in the daytime case and the concentrations of O3 due to the downward transport of ozone from the upper atmosphere toward the surface were also much higher at night than during the day. Consequently, the atmospheric pollutant concentrations in the mountainous coastal region under the downslope wind storms were higher than those after and before the occurrences of wind storms.

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The Meaning of Pre-service Educare Teachers' Experiences about Child Safety Management Classes based on Problem Based Learning (PBL) (문제중심학습(PBL)을 적용한 아동안전관리 수업이 예비보육교사에게 주는 경험의 의미)

  • Seo, Young Hee;Jung, Hye Young
    • Korean Journal of Childcare and Education
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    • v.8 no.1
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    • pp.145-167
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    • 2012
  • The objective of this study is to investigate the meaning of pre-service educare teachers' experience about child safety management classes based on Problem Based Learning (PBL). The participants in this study were thirty five sophomores majoring in Social Welfare, and fifteen weeks of data were collected. The participants were given five problems that were related with real situations. During the given period, they made documents from reflective journals, group or individual interviews, and online community resources. Analyzing the documents sheds light on the meaning of the pre-service educare teachers' experience. The results are as follows: First, pre-service educare teachers found themselves recovering confidence, earning recognitions from others, and pursuing their study. Second, they showed continuous conflicts not only with the PBL approach but also with themselves and group members. Finally, they experienced mutual help and interactions among the group members thorough their cooperative learning and they realized the meaning of cooperative learning by means of comparisons and references between the groups. In conclusion, this study confirms the applicability of PBL to the educare teacher training courses and points out specific ways to alleviate the conflicts in applying PBL to class needs in future studies.

The Research about Efficient Control of the Territorial Base Point (영해기준점의 효율적 유지관리 방안에 관한 연구)

  • Choi, Yun-Soo;Kim, Jae-Myeong;Yun, Chang-Beom
    • Spatial Information Research
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    • v.18 no.1
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    • pp.39-48
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    • 2010
  • Recently, many countries are promoting the rapid development of marine for securing territorial sea. The importance of territorial sea has being emphasized as territorial disputes among countries has been increasing. The South Korea should be encouraged to expand the territory due to territorial disputes with neighborhood countries. The purpose of this study is to derive a improvement plan for the efficient control of the territorial base point through analyzing the existing territorial base point and checking the territorial base point. Therefore, we proposed a variety of new plans for accurate positioning by sea level observation and MBES, reduced the surveying procedure through analyzing the existing territorial base points and provided a basis for the territorial base points which can be the 2nd grade national control points by improving a grade. We also suggested that the territorial base points and sub-territorial base points' database should be given standardized number for increasing the efficient management of other national control points and territorial base points. Finally, we suggested a improved work regulation about analysis and maintenance for territorial base points, the information activity of territorial base points and the new plan of community relations. This study will be a basis for the foundation of maritime territory which could be superior to other countries and the expansion of maritime territory.

Development of Audio-visual Aids of Death Education for Hospice Patients and Their Families (호스피스 환자와 가족을 위한 임종교육 시청각 자료 개발)

  • Seo, Mi-Suk;Kang, Yu Jung;Yoon, Ji Yoon;Kim, Tae Yeon;Cho, Hye Jun;Park, So Yeon;Lee, Si Yeon;Jang, Ji Hye;Kim, Yu Jin;Kang, Mi Teum
    • Journal of Hospice and Palliative Care
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    • v.19 no.3
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    • pp.240-248
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    • 2016
  • Purpose: Patients and their caretakers need to understand various problems and requirements in the dying process so that they may prepare for death for the rest of their remaining life. Accordingly, a systematic audio-visual resource was developed to educate hospice patients and their families at the palliative care ward about the process of dying. Methods: For the development of an audio-visual resource, a initial education material was produced in the form of simple and accessible Power Point handouts based on literature study. Then, the program was completed through five rounds of a process, including expert advice, revision, update and evaluation. Results: The final version of the program was filmed with cooperation of the medical literature information division. Using the program, patients and families were educated through five phases over three sessions for a total 26 minutes and 34 seconds. Conclusion: The significance of this study lies in the fact that it was conducted after the establishment of the palliative care ward, which made it easier for nurses provide the education. It is expected that the program may be used by hospice specialists as well as nurses as an education resource for hospice patients and their families.

Bookstart in the UK: its operation and significance -A case study of Bookstart in Sheffield- (영국 북스타트 운동의 의의와 그 추진 현황 -세필드 북스타트를 중심으로-)

  • Kim, Young-Seok
    • Journal of the Korean Society for Library and Information Science
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    • v.38 no.2
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    • pp.291-313
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    • 2004
  • Bookstart is a gifting project, which aims to provide free books to babies in order to promote the idea of early book sharing and to develop a life long love of books. Bookstart was initiated in the UK in 1992 by the independent charity Booktrust in co-operation with Birmingham Library Services, South Birmingham Health Authority and Birmingham University School of Education. The idea of Bookstart has begun to spread not only to Korea but also to other countries. Bookstart In Korea is due to actively operate In many local governments. Therefore. many library researchers, scholars and professionals. council officers and ordinary people who are involved in Bookstart in Korea are urgently looking for materials on Bookstart in the UK. Consequently, this study examines Bookstart in the UK and the main aims of this study are: to produce results applicable to the successful operation of Bookstart in Korea : to give Bookstart-related people an understanding of many aspects of the operation of Bookstart; and to provide Ideas and information on the operation of Bookstart in Korea. In order to obtain useful data. the researcher used a questionnaire and interview method and reviewed the literature. The study revealed that Bookstart In the UK aims not only to promote babies' Interest In books and reading but also to Improve family relationships and to tackle social exclusion.

Typeface Design 'Arita' for Typographic Identity (타이포그래픽 아이덴티티를 위한 글자꼴 '아리따')

  • Ahn, Sang-Soo;Lee, Yong-Je;Han, Jae-Joon
    • Archives of design research
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    • v.19 no.6 s.68
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    • pp.33-38
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    • 2006
  • The development of the typeface 'Arita' presents a method and its following results for a corporate typographic identity. Amore pacific established a strategy for a typographic identity as for their high quality corporate culture and as a first step for it was to develop their corporate typeface 'Arita'. The typeface 'Arita' which pursues sharing and accompanying was developed to be used in the body text to enhance the function of the typography. What was needed to develop this typeface for Amore pacific was first, understanding of the corporation, and second, vision to present new direction for a typeface and its appropriate supervision, and third, ability in designing. Therefore, under the leading of Hong-ik University's meta design research institute, the typeface 'Arita' was created by in collaboration with Seoul women's university's modeling research institute and the typeface design specialty company, type space and the design company, Ahn-graphics. There are two kinds of weight in 'Arita' typeface, one is normal 'AritaM' and the other is semibold 'AritaSB'. 'Arita' is produced into TrueTypeFont(TTF) for Windows Operating System and OpenTypeFont(OTF) for Macintosh Operating System.

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Performance Analysis of the Amplify-and-Forward Scheme under Interference Constraint and Physical Layer Security (물리 계층 보안과 간섭 제약 환경에서 증폭 후 전송 기법의 성능 분석)

  • Pham, Ngoc Son;Kong, Hyung-Yun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.1
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    • pp.179-187
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    • 2014
  • The underlay protocol is a cognitive radio method in which secondary or cognitive users use the same frequency without affecting the quality of service (QoS) for the primary users. In addition, because of the broadcast characteristics of the wireless environment, some nodes, which are called eavesdropper nodes, want to illegally receive information that is intended for other communication links. Hence, Physical Layer Security is applied considering the achievable secrecy rate (ASR) to prevent this from happening. In this paper, a performance analysis of the amplify-and-forward scheme under an interference constraint and Physical Layer Security is investigated in the cooperative communication mode. In this model, the relays use an amplify-and- forward method to help transmit signals from a source to a destination. The best relay is chosen using an opportunistic relay selection method, which is based on the end-to-end ASR. The system performance is evaluated in terms of the outage probability of the ASR. The lower and upper bounds of this probability, based on the global statistical channel state information (CSI), are derived in closed form. Our simulation results show that the system performance improves when the distances from the relays to the eavesdropper are larger than the distances from the relays to the destination, and the cognitive network is far enough from the primary user.

Plan of the Social Capital Formation for the Resolving the Regional Conflict -focus on the case of Cheonan- (지역갈등해소를 위한 사회자본 형성방안 -천안시를 중심으로-)

  • Park, Jong Gwan
    • The Journal of the Korea Contents Association
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    • v.13 no.11
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    • pp.167-175
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    • 2013
  • This paper studied the resolving the regional conflict method through the community capital formation. For this purpose, the theoretical background about the social capital, function of the social capital and component, and regional conflict factor were organized. In addition, it analyze empitically through the survey. First, in order to resolve the frequency analysis result regional conflict, the social capital formation was exposed to be important. Next, the regression analysis result, the factor of social capital and the local egoism, the local participation, and the problem of local areas, each, it was expressed as the coefficient of determination 5.1%, 5.5%, 1.6%, and F value showed up as 4.030, 4.3,51, 1.194. This demonstrates that it is decreased the regional conflict as the social capital formation is high. That is, the social capital formation was proved at the resolving the regional conflict that there was lots of the correlation. The community and penis organizationThe local residents should cooperate together and it should try. Particularly, the 20 generations and 30 generations in which the social capital is weak, the social capital formation strategy about the 20 generations and 30 generations should be studied.

Digital Library Research : Major Issues and Trends (디지털도서관 연구 동향(2))

  • Ahn, Hyun-Soo
    • Journal of Information Management
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    • v.31 no.1
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    • pp.12-42
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    • 2000
  • Digital library research has attracted much attention. While many research projects are funded by government agencies and national and international bodies, some are run by specific academic and research institutions and libraries. While some digital library projects, such as the ELINOR project in the UK, the first two phases of the eLib(Electronic Libraries) programme in the UK, and the first phase of the DLI(Digital Library Initiative) in the USA, are now over, a number of other projects are currently under-way in different parts of the world. Beginning with the definitions and characteristics of digital libraries proposed by various researchers, this paper provides brief accounts of some major digital library projects that are currently in progress, or are just completed, in different parts of the world. There follows a review of digital library research under 16 major headings. Literature for this review has been identified through a search on the LISA CD-ROM database and a Dialog search on library and information science databases, and the resulting output has been supplemented by a scan of the various issues of D-Lib Magazine and Ariadne, and the Web sites of various organizations and institutions engaged in digital library research. The review indicates that we have learned a lot through digital library research within a short span of time. However, a number of issues are yet to be resolved. The paper ends with an indication of the research issues that need to be addressed and resolved in the near future in order to bring the digital library from the researcher's laboratory to the real life environment.

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