• Journal of Communications and Networks
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• 제15권3호
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• pp.266-275
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• 2013

The exact closed-form expressions for outage probability and bit error rate of spectrum sharing-based multi-hop decode-and-forward (DF) relay networks in non-identical Rayleigh fading channels are derived. We also provide the approximate closed-form expression for the system ergodic capacity. Utilizing these tractable analytical formulas, we can study the impact of key network parameters on the performance of cognitive multi-hop relay networks under interference constraints. Using a linear network model, we derive an optimum relay position scheme by numerically solving an optimization problem of balancing average signal-to-noise ratio (SNR) of each hop. The numerical results show that the optimal scheme leads to SNR performance gains of more than 1 dB. All the analytical expressions are verified by Monte-Carlo simulations confirming the advantage of multihop DF relaying networks in cognitive environments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권8호
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• pp.2764-2782
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• 2021

Existing city-level boundary nodes identification methods need to locate all IP addresses on the path to differentiate which IP is the boundary node. However, these methods are susceptible to time-delay, the accuracy of location information and other factors, and the resource consumption of locating all IPes is tremendous. To improve the recognition rate and reduce the locating cost, this paper proposes an algorithm for city-level boundary node identification based on bidirectional approaching. Different from the existing methods based on time-delay information and location results, the proposed algorithm uses topological analysis to construct a set of candidate boundary nodes and then identifies the boundary nodes. The proposed algorithm can identify the boundary of the target city network without high-precision location information and dramatically reduces resource consumption compared with the traditional algorithm. Meanwhile, it can label some errors in the existing IP address database. Based on 45,182,326 measurement results from Zhengzhou, Chengdu and Hangzhou in China and New York, Los Angeles and Dallas in the United States, the experimental results show that: The algorithm can accurately identify the city boundary nodes using only 20.33% location resources, and more than 80.29% of the boundary nodes can be mined with a precision of more than 70.73%.

• International Journal of Computer Science & Network Security
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• 제22권1호
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• pp.324-330
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• 2022

At the present stage of the world economic development, a new economic system is being formed, in which non-economic values, in particular environmental and social parameters, have become widespread. A new vision of economic activity is being formed, which acquires the qualities of Smart-economy. The purpose of this paper is reveal the features of managing the development of smart cities as specific entities of the Smart-economy. New functions of economic entities are formed within the framework of the Smart-economy concept, while their role and weight in the localities' activity or formation have changed. Determining that the key trends in the Smart-economy development are such as digitalization, greening, socialization, institutionalization, and urbanization, this is necessary to note that all these trends are most active in the formation of urban ecosystems. These trends are determined by the general population growth and the urban population growth, which requires considerable attention to planning each city's development itself. Such planning could ensure the comfort of living for all its inhabitants, quality, safe, and modern life. The Smart-city's key elements and the intellectualized approach implementation planes to the decision of these or those tasks are definedIt is determined that a new ecosystem of governance is being formed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권3호
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• pp.1030-1050
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• 2021

The edges with "bridge characteristic" play the role of connecting the communication between regions in power optical cable network. To solve the problem of mining edges with "bridge characteristic" in provincial power optical cable network, the complex power optical cable network model is constructed. Firstly, to measure the generated potential energy of all nodes in n-level neighborhood local structure for one edge, the n-level neighborhood local structure topological potential is designed. And the minimum connected chain attenuation is designed to measure the attenuation degree caused by substituted edges. On the basis of that, the minimum connected chain attenuation topological potential based measurement is designed. By using the designed measurement, a bridge-edges mining algorithm is proposed to mine edges with "bridge characteristic". The experiments are conducted on the physical topology of the power optical cable network in Jilin Province. Compared with that of other three typical methods, the network efficiency and connectivity of the proposed method are decreased by 3.58% and 28.79% on average respectively. And the proposed method can not only mine optical cable connection with typical "bridge characteristic" but also can mine optical cables without obvious characteristics of city or voltage, but it have "bridge characteristic" in the topology structure.

• 지식경영연구
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• 제12권2호
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• pp.69-80
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• 2011

This paper reports on a structural view of a knowledge network comprised of clubs and organisationsexpressly concerned with cultural activities in a regional Australian city. Social network analysis showed an uneven distribution of power, influence, and prominence in the network. The network structure consisted of two modules of vertices clustered around particular categories of creative arts and these modules were linked most frequently by several organisations acting as communication hubs and boundary spanners. The implications of the findings include 'network weaving' for improving the network structure and developing a systemic approach for exploring the structures of social action that form community-based knowledge networks.

• 한국농촌건축학회논문집
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• 제13권3호
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• pp.11-20
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• 2011

The present age demands a change in attitude based on a differentiated life value from city. It will provide to a fundamental solution for the gap of living level in the farming and fishing communities and recreate distinguishing comfortable communities. The purpose of this study was to deduct the formation characteristics of the townscape of Korean slow city according to analyze resources and structure of landscape. Planning of slow city's townscape is a process of imagification of filtrate unique meaning. The glob share synchronic unique values by slow city's network. Therefore instead of putting emphasis on promoting tourist business for short-term revenue, it will be under control to raise the standard of living and to be not forfeited and diluted the rights for sustainable slow city's status. Participation of resident needs in this process. Accordingly it need a strategy of landscape formation design and a interdepartmental practice system for a continuous slow city's image by renewal of disharmonious townscape in the built-up area.

• 한국콘텐츠학회논문지
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• 제20권8호
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• pp.19-33
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• 2020

본 연구의 목적은 빅데이터 분석 기법을 이용하여 세종시 건설 계획에 대한 여론 변화를 분석하는 것이다. 연구 자료는 세종시 건설 계획과 관련된 한겨레와 동아일보, 한국일보 등 언론사의 신문기사이다. 세종시 건설 계획은 신행정수도, 행정중심복합도시, 세종시 수정안 등 3개 시기로 구분되었다. 분석 방법은 파이썬과 Gephi 0.9.2 프로그램을 활용한 빈도분석, 감성분석, 사회연결망분석이다. 세종시 건설에 따라 각 신문사의 쟁점에 대한 변화가 있었다. 첫째, 빈도분석 결과, 한겨레의 키워드는 세종시 건설 시기에 따라 찬성-찬성-반대의 특성을 나타내고 있었다. 동아일보는 반대-반대-찬성의 입장을 갖는 것으로 분석되었다. 한국일보는 반대-찬성-반대 경향을 갖는 것으로 분석되었다. 둘째, 감성분석 결과, 각 언론사는 논조의 특성이 변화되고 있었다. 한겨레는 긍정-긍정-부정 논조 특성을 보이고 있었고, 동아일보는 부정 - 부정 - 긍정으로 변화되었다. 한국일보는 부정-긍정-부정으로 변화되었다. 셋째, 사회연결망분석 결과는 다음과 같다. 각 언론사는 세종시 건설 시기에 진보와 보수, 중도 등 정치적, 이념적 특성에 따라 변화를 보이고 있었다. 한겨레는 지역균형발전에 초점을 맞추고 있었으며, 동아일보는 보수의 의견을 대변하고 있었다. 한국일보는 세종시 건설 시기에 여·야가 대립하는 이슈에 대해 부각 시키고 있었다.

• IT SoC Magazine
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• 제26권9호
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• pp.48-49
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• 2008

• 한국지역지리학회지
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• 제11권5호
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• pp.391-404
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• 2005

본 연구는 대구지역의 기업지원 및 연구기관의 현황, 네트워크 실태와 그 특성을 설문조사 결과를 중심으로 분석하였다. 대구지역의 기업지원 및 연구기관은 1990년대에 주로 설립되었고, 지역 종합대학과 산업단지가 입지하고 있는 북구와 달서구를 중심으로 분포하고 있다. 이들 기관들은 대체로 1-5개 기관과 네트워크 관계를 가지며, 기관 간 네트워크의 주된 역할은 기술 및 시장동향 등 기업이 필요로 하는 정보의 제공이고, 주요 업무는 지역기업에 대한 교육과 응용연구이다. 네트워크 유형은 비공식적 형태가 많고, 교류되는 정보는 과학/연구 및 기술과 기업동향이 중심이다. 이들 기관으로부터의 분리창업은 활발하지 않으나 분리창업한 기업들은 대부된 대구지역에 입지하며, 이들 기업과 기관 간의 네트워크 관계는 기관 상호간 네트워크보다는 상대적으로 활발하며 그 목적도 주로 관련 기술정보 교환이며 공식적 형태가 중심이다.

• 대한전자공학회논문지TC
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• 제43권5호
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• pp.51-58
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• 2006

효율적인 도심 관리를 위해 다양한 시스템들이 사용되어 왔다. 본고에서는, radio over fiber (RoF) 와 passive optical network (PON) 기술을 결합하여 각 시스템 장점들을 이용하는 통합 도심 관리 시스템 (IUMS)을 소개한다. 아울러, 미래 ubiquitous city (U-city)의 실현을 위한 통합 도심 관리 시스템 적용의 타당성을 부여하기 위해 버스 정보 시스템 (BIS), 유무선 방재 시스템 (DDPS) 및 실시간 위치 정보 추적 시스템 (RTLS) 등을 포함한 다양한 통합 도심 관리 시스템을 적용한 서비스들을 상세히 기술한다.