• Title/Summary/Keyword: Network Infrastructure

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A Study on the Improvement Plans for the Wild Bird Habitat in an Urban River - A Case Study on Seongnaecheon(Stream) in Seoul - (도시하천 야생조류의 서식 기능 향상방안 연구 - 서울시 성내천을 대상으로 -)

  • Park, Goon-Sook;Park, Seok-Cheol;Han, Bong-Ho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.23 no.3
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    • pp.23-43
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    • 2020
  • The purpose of this paper is to create ecological values for urban rivers. For this, the paper looks into river bed structures and how nearby lands are used. This study was performed to set the specific sections for analysis through a field investigation of the infrastructure conditions, surrounding land use, and the inter habitat structure of Seongnaecheon(Stream). A total of 780 individuals from 31 species of wild birds appeared in Seongnaecheon(Stream). According to foraging guild's habitat, there were 9 species of water, 8 types of water edges, 5 types of crowns, 5 types of shrubs, 2 types of tree trunks, 2 types of birds of raptors, and 355 individuals of water, 243 shrubs, 90 crowns, 84 water edges and 5 raptors. Many water birds were observed at the site where the Seongnaecheon(Stream) sandy plains and wetland herbaceous area were developed and the open water was secured. Most of the forest birds appeared on levee slope connected with forest around and riverside with fewer facilities for use. The species diversity index of Shannon, the entire section of Seongnaecheon(Stream), was 2.2697 and the downstream ecological landscape conservation area of Seongnaecheon(Stream) was found to be useful as a habitat for wild birds in the city compared to other sections. Some sections of Seongnaecheon (Stream) had low species diversity index due to lack of green space and surrounding urbanization areas. In choosing target species, I researched the special features of the habitats and the habitation structure of wild birds in each zone. Regarding detailed plans, by classifying the breeding place & roosting site and the roosting site & shelter that took account of the inhabitation characteristics of the target species in different sections, this paper suggested the major plant species and multilayer planting structures. Moreover, this study proposed the development of habitats for water birds and forest birds along with the connection of the green network for improving the Eco-corridor linkage and inhabitation features in Seongnaecheon(Stream).

Analysis on the Credit Guarantee System for Creative Economy in Korea (창조경제 활성화를 위한 금융지원 방안에 대한 연구 : 신용보증제도를 중심으로)

  • Yoo, Kyeongwon;Kim, Kyungkeun;Bae, Sang Hoo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.6
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    • pp.47-64
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    • 2014
  • Considering the network externality and spill-over effects, this paper constructs the theoretical model for analyzing the financial policies focusing on the credit guarantee system for Creative Economy, which has been set as the new policy paradigm for the Korean Economy. The analytical results show that it is as much as important to improve the efficiency of the financial markets and construct the infrastructure for reducing the information asymmetry problem which would be more serious in the creative finance. Although it is important to fill the gap due to the market failure it is also crucial to construct the appropriate financial schemes for the various stages of the innovative firms growth. Without these, the impacts of current public funding policies may crowd out the amount of private market funds for the innovative firms or reduce the possibility of commercialization of new technologies in these firms. Based on the evaluation of current related public policies from the perspectives of creative finance, we imply that the current financial policies appear to be quantity oriented not the quality based. Although the policy goals would be appropriately set for vitalizing the Creative Economy in Korea, they appear to be still unsuccessful to address the information asymmetry issue which is the major concern in vitalizing the creative economy. Thus we emphasize the market friendly policies, risk-sharing between the various market participants, revitalizing the relationship banking and efficient management of credit guarantee system in Korea based on the analytical model as well as the evaluation of related policies regarding the creative economy.

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Design of a Real-Time Certificate Status Validation Mechanism Using Identity Information Hash Value of Signer (서명자의 신원정보 해쉬값을 이용한 실시간 인증서 상태 검증 메커니즘의 설계)

  • Kim Hyun-Chul;Kim Jung-Jae;Lee Jong-Hee;Oh Hae-Seok;Jun Moon-Seog
    • The KIPS Transactions:PartC
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    • v.13C no.2 s.105
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    • pp.147-154
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    • 2006
  • The certificate status validation mechanism is a critical component of a public key infrastructure based on certificate system. The most generally mechanisms used these days are the use of the certificate revocation list and the real-time certificate status protocol. But the certificate revocation list can not give the real-time certificate status because the certificate is being delivered periodically, and the real-time certificate status protocol method will generate a concentrated load to the server because the protocol in the central server will be accessed whenever a certification is necessary. It will also take a long time to validate the certificate because each trade has to send mass information through the network. This paper will present that real-time validation is guaranteed as the real-time certificate status protocol method and the traffic congestion in the network Is reduced in a way that the certification would be requested using the user information hash value and would be validated using the user information kept in the certification authorities and the service providers. Based on the this study, we suggest a real-time certificate status validation mechanism which can reduce the certificate status validation time using the signed user information hash value. And we confirm speed of certificate status verification faster than existing CRL(Certificate Revocation List) and OCSP(Online Certificate Status Protocol) method by test.

P2P-based Mobility Management Protocol for Global Seamless Handover in Heterogeneous Wireless Network (이기종망에서 글로벌 끊김 없는 핸드오버를 위한 P2P 기반 이동성 관리 프로토콜)

  • Chun, Seung-Man;Lee, Seung-Mu;Park, Jong-Tae
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.12
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    • pp.73-80
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    • 2012
  • In this article, we propose a P2P-based mobility management protocol for global seamless handover in heterogeneous wireless networks. Unlike previous mobility management protocols such as IETF MIPv4/6 and its variants, the proposed protocol can support global seamless handover without changing the existing network infrastructure. The idea of the proposed protocol is that the location management function for mobility management is separately supported from packet forwarding function, and bidirectional IP tunnels for packet transmission are dynamically constructed between two end-to-end mobile hosts. In addition, early handover techniques have been developed to avoid large handover delays and packet losses using the IEEE 802.21 Media Independent Handover functions. The architecture and signaling procedure of the proposed protocol have been designed in detail, and the mathematical analysis and simulation have been done for performance evaluation. The performance results show that the proposed protocol outperforms the existing MIPv6 and HMIPv6 in terms of handover latency and packet loss.

xDSL 표준화동향

  • 김기호
    • Information and Communications Magazine
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    • v.14 no.12
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    • pp.77-85
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    • 1997
  • 지금까지 access network에서의 xDSL의 위치를 살펴보고 DSL, HDSL, ADSL 및 VDSL을 중심으로 기술 및 최근의 표준화동향을 살펴보았다. ITU의 조사에 따르면 97년 기준으로 전세계 약 8억가구에 copper access line이 연결되어 있고 그중의 70%이상이 가정에 연결되어 있는데 증가추세도 북미의 경우 년3.5%, 서유럽과 태평양연안의 경우 년4.5%의 성장율을 보이고 있어 2000년경에는 10억가구에 다다를 전망이다. 미국은 97년기준 약 1억가구에 1억6000만 copper access line이 연결되어 있는데 Yankee Group이 조사한 바에 따르면 2000년을 기준으로 3백만가구에 ADSL/RADSL/SDSL이 연결되고 관련 revenue는 10억달러에 이를것으로 추산하고 있다. 전세계 xDSL 시장규모를 미국의 5배정도로 보면 2000년경에는 전세계 twist pair의 2%정도에 xDSL이 연결되어 ADSL/RADSL/SDSL 관련 세계시장규모가 50억달러에 이르고 시장성장률은 30%에 이를 것으로 보고 있다. 현재 이러한 xDSL의 표준화작업은 3장에서 언급한 바와 같이 ANSI T1, ETSI에서 주로 주도되고 있으나 ITU-T, IEEE, ADSL Forum, ATM Forum, DAVIC 등 다른 group과 활발한 liasion meeting 을 통해서도 협력안을 마련하려 노력하고 있다. 예를 들어 DAVIC은 long range(1.5Km이상) PMD규격으로 ADSL을, mid range($300m\sim1.5km$) PMD규격으로 VDSL을, short range(300m이하) PMD규격으로 CAP방식의 FTTC를 각각구정하여 xDSL을 수용하고 있다. Microsoft의 CEO인 Bill Gates가 'Bandwidth bottleneck. No question. that's the biggest obstacle.'이라고 천명한 바와 같이 정보사회로의 진전에 있어 bandwidth는 시급히 해결되어야 할 문제이다. 정보사회의 꿈을 실현하고자 1993년부터 시작된 In-formation Infrastructure의 구축노력이 그동안 다양하게 시도되어왔으나 숱한 우여곡절과 실패를 겪은 telco등의 서비스업자들이 이제는 너무 큰 꿈을 쫓기보다는 internet이라는 현실적인 시장에서 xDSL과 cablemodem을 바탕으로 차근차근 새로 시작하고 있다고 생각된다. 그동안 ADSL, Forum을 중심으로한 일부 technology evangelist들은 전세계 8억가구에 깔려있는 copper twist pair를 경제적인 'the last mile solution'으로 활용할 것을 줄기차게 주장해왔다. 그동안 xDSL은 VDSL이라는 차세대 대안을 제시하여 interim solution이라는 울타리를 벗어나는데 성공하였을 뿐만 아니라 IDSL, SDSL, RADSL등의 새로운 고객지향적 xDSL을 개발하여 선택의 폭을 넓혀주었다. xDSL vendor들간의 치열한 경쟁속에서 값싼 xDSL 시스템들이 속속 등장하고 있으며, DSLAM[8]과 같은 switch solution도 제시되어 기존의 copper twist pair를 이용해 값싸게 다양한서비스를 제공해 줄 수 있는 기틀을 마련한 것이 오늘날의 xDSL의 성공요인이라고 생각된다. 일찌기 Bell Atlantic의 CEO Ray Smith가 'Yes. ADSL is an interim solution that will be with us for forty years.'라고 간파한대로 xDSL은 fiber가 좀 더 값싼 해결책이 될 때까지 당분간 access network에서 확고한 자리를 구축할 것으로 보인다. 최근들어 우리나라의 초고속정보통신망도 ADSL 과 VDSL을 바탕으로 FTTH으로 진화하는 전략을 수립한것은 우리의 현실과 세계적인 추세를 반영한 일이라 여겨진다.

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Youth Startup Firms: A Case Study on the Survival Strategy for Creating Business Performance (청년창업기업의 창업초기 생존전략 : 중진공 청년전용자금 활용기업 사례)

  • Lee, Seung-Chang;Lim, Won-Ho;Suh, Eung-Kyo
    • Journal of Distribution Science
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    • v.12 no.6
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    • pp.81-88
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    • 2014
  • Purpose - Entrepreneurship promotion is emerging as an important economic growth agenda. However, in Korea, entrepreneurship has weakened because of the collapse of the venture bubbles of the 2000s and the global economic recession in 2008, which have induced the business community to choose stability over risk. The Korean government has been implementing several support projects to inspire and promote youth entrepreneurship through various means including financial assistance; however, the perpetuation rate of young entrepreneurship is still low as compared to advanced economies such as the US and EU. This case study focuses on the Youth Start-Up Business Support Program of the Small & Medium Business Corporation, and explores practical alternatives. Further, it aims to suggest managerial factors and a conceptual model for change management factors affecting the business performance creation of a startup company, based on the Small and medium Business Corporation's young venture startup fund. Research design, data, and methodology - Many studies examine the current progress and issues of startup firms, for example, a lack of systematic cultivation of entrepreneurship and startup business training, lack of commercialization funding for youth startup businesses, lack of mentoring, and inadequate infrastructure. From prior research, we address four factors, namely, personal managerial capabilities, innovative business model, sufficient cash flow, and social network, affecting startup companies' business performance. This study involved a sample survey of 200 young entrepreneurs to investigate casual relations between the four factors and business performance. A regression analysis was used to verify the hypotheses. Results - First, in relation to differences in the founder's personal characteristics, age, sales amount, and number of employees significantly impact business performance. Second, regarding the causal relation between the four factors for creating business performance, an innovative business model and social networking have supported the hypotheses, revealing that the more that a start-up founder has an innovative business model and social networking, the more the start-up firms are likely to have better performance (e.g., sales volume, employment, ROE, ROI, etc.). Although the founder's competency and sufficient cash flow have no significant relationship with business performance, the mean value was higher performance for high founder's competency and sufficient cash flow. Conclusions - This study provides basic data on policy support strategies of the Small and Medium Business Corporation, to help young entrepreneurs achieve their start-up business goals. It shows that young entrepreneurship startup firms should strive to explore ideas to satisfy customers' needs, and that changes in customer value and the continuous innovation of business model differentiation are required to actively respond to change management. Moreover, at the infant startup stage, they should activate social network programs to share information, thereby offsetting resource scarcity and managing business risk. Further, the establishment of a long-term vision and the implementation of training programs in related specific fields should be supported to strengthen founders' personal capabilities.

A Research on the Implementation and Estimation of an Integrated System for Information Management in the Field of Nuclear Science and Engineering (원자력분야 학술정보 통합정보관리시스템 구현에 관한 연구)

  • Chun, Young-Choon
    • Journal of Information Management
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    • v.34 no.4
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    • pp.63-84
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    • 2003
  • This research is a case study that describes the NUCLIS21(Nuclear Information System 21), an integrated web-based information management system of KAERI(Korea Atomic Energy Research Institute), implemented to carry out the role of a national nuclear information center with government support as an information infra implementation programme. Through its user-centered single interface, the system aims at building an infrastructure for the national nuclear information center, as well as improving the information management system of the TID(Technical Information Department) within the institute. The system consists of two major parts which are an integrated module of the MIS and six different kinds of system. These include the Integral search system with OPAC, My Library, the Acquisition system, the Catalogue system, the Information Supply system, and the Serial Publication system. The DB is composed of Bibliographical DB, Original text DB and Abstract DB. A special feature of this system was designed as a unified network system through connection to MIS(Management Integration System) of the institute, so users can get research information for projects. Therefore, they have access to available information easily and access to the ongoing service of this system. Furthermore, users can share information by using our system. The survey has it that 75.7%(200 persons), 62.1%(164 persons) and 78.4%(207 persons) of the respondents are satisfied with the fidelity, speediness, and convenience of the system respectively, and the overall satisfaction of the respondents is comparably high.

A Study on the Web-based Map Algebraic Processor (웹 기반 지도대수 처리기에 관한 연구)

  • 박기호
    • Spatial Information Research
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    • v.5 no.2
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    • pp.147-160
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    • 1997
  • "The "Map Algebra", beeing recognized as a viable theoretical framework for GIS (Geographica Infonnation System), models map layers as "operands" which are the basic unit of geo-processing, and a variety of GIS commands as "operators." In this paper, we attempt at lifting some limitations of map algebras proposed in GIS literature. First, we model map layer as "function" such that we may employ the notion of meta operator (or, higher-order funtion) available in the functional programming paradigm. This approach provides map algebraic language with "programmability" needed in GIS user language. Second, we extend the semantics of, and improve on the sytactic structure of map algebraic language. Mer the data model and language associated with map algebra are formalized, we proceed to design and implement a prototype of map algebraic processor. The parser of the language in our prototype plays the role of transforming the native and heterogeneous user language of current GISs into a canonical map algebraic language. The prototype, named "MapSee" is a proof-of-concept system for the ideas we propsed in this paper. We believe that the uniform interface based on the map algebraic language will make promising infrastructure to support "Internet GIS." This is because the uniform but powerful interface through the Web clients allow access to both geo-data and geo-processing resources distributed over the network.to both geo-data and geo-processing resources distributed over the network.

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Study on Modernized Real Estate Transaction System based on Spatial Information (공간정보기반 부동산거래선진화시스템 구축방안)

  • Cho, Chun Man;Chung, Moon Sub
    • Spatial Information Research
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    • v.21 no.6
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    • pp.69-80
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    • 2013
  • Our country has made every efforts to develop Real Estate Transaction culture with emphasis on Licensed Realtors by introducing Real Estate Transaction Law in 1983. Also, MOLIT(Ministry of Land, Infrastructure and Transport) designated several organizations including KAR(Korea Association of Realtors) as Real Estate Transaction Information Network Licensees for data credibility enhancement and transaction transparency. Nevertheless, the level of law abiding spirit and transaction culture are still similar to those of the old 'Bokdeokbang' era. The under-developed transaction behaviors prevent the social capital of people's credibility on Licensed Realtors from advancing, and results in the outcomes of unnecessary social cost. That is, very low credibility on the data on Sales Items in the market and the fear of speculative real estate price uprise and market distortions are continuing on. In this context, the purpose of this study is to propose the model of GIS-based Modernized Real Estate Transaction System and its execution policies to support credible Real Estate Information to the general public for efficient transactions in the market. Accordingly, the study aims at contributing to the modernization of Real Estate Transactions, fostering competitiveness of Realtors in the Real Estate Market.

Spatial Location Modeling for the Efficient Placements of the Super WiFi Facilities Utilizing White Spaces (화이트 스페이스를 활용한 슈퍼 와이파이 시설의 효율적 배치를 위한 공간 입지 모델링)

  • Lee, Gunhak;Kim, Kamyoung
    • Journal of the Korean Geographical Society
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    • v.48 no.2
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    • pp.259-271
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    • 2013
  • This paper addresses the efficient facility placements to adopt a super WiFi network, taking significant considerations as the next generation 'information highway'. Since the super WiFi has a wider geographic coverage by utilizing the white spaces of TV broadcasting which are empty and available frequencies for the wireless communications, it would play an important role in releasing digital divide of the internet access for low populated or mountainous areas. The purpose of this paper is to explore systematic and efficient spatial plans for the super WiFi. For doing this, we applied optimal location covering models to Gurye-gun, Jeonlanamdo. From the application, we presented optimal locations for super WiFi facilities and significant analytical results, such as the tradeoff between the number of facilities and coverage and marginal coverage for establishing super WiFi network. The results of this research would be usefully utilized for decision makers who wish to adopt a super WiFi, to extend wireless networks in a city or build a regional infrastructure of wireless facilities.

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