• 제목/요약/키워드: Network Connectivity

검색결과 765건 처리시간 0.024초

Mobile Sensor Network Simulator for efficiency Coverage (효율적인 Coverage 결정을 위한 모바일 센서 네트워크 시뮬레이터)

  • Lee, Chang-Wu;Lee, Heon-Jong;Han, Youn-Hee;Jeong, Young-Sik
    • Proceedings of the Korea Information Processing Society Conference
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    • 한국정보처리학회 2009년도 추계학술발표대회
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    • pp.131-132
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    • 2009
  • 지형의 상태를 알 수 없는 타겟 지역에 구축되는 USN 환경은 각기 서로 다른 connectivity degree와 이동 가능한 센서들의 수를 가지면서 coverage의 최대화를 요구한다. 본 논문에서 설계한 모바일 센서 네트워크 시뮬레이터(MSNS)는 USN 환경을 GML로 구성하고, 각 센서들의 센싱/통신 범위가 설정된 센서 노드들의 수와 유지해야할 connectivity를 입력받아 주어진 조건에서 타겟 영역이 얼마나 효율적으로 coverage되는지를 가시화한다.

Maximizing Network Utilization in IEEE 802.21 Assisted Vertical Handover over Wireless Heterogeneous Networks

  • Pandey, Dinesh;Kim, Beom Hun;Gang, Hui-Seon;Kwon, Goo-Rak;Pyun, Jae-Young
    • Journal of Information Processing Systems
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    • 제14권3호
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    • pp.771-789
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    • 2018
  • In heterogeneous wireless networks supporting multi-access services, selecting the best network from among the possible heterogeneous connections and providing seamless service during handover for a higher Quality of Services (QoSs) is a big challenge. Thus, we need an intelligent vertical handover (VHO) decision using suitable network parameters. In the conventional VHOs, various network parameters (i.e., signal strength, bandwidth, dropping probability, monetary cost of service, and power consumption) have been used to measure network status and select the preferred network. Because of various parameter features defined in each wireless/mobile network, the parameter conversion between different networks is required for a handover decision. Therefore, the handover process is highly complex and the selection of parameters is always an issue. In this paper, we present how to maximize network utilization as more than one target network exists during VHO. Also, we show how network parameters can be imbedded into IEEE 802.21-based signaling procedures to provide seamless connectivity during a handover. The network simulation showed that QoS-effective target network selection could be achieved by choosing the suitable parameters from Layers 1 and 2 in each candidate network.

Context-aware Connectivity Analysis Method using Context Data Prediction Model in Delay Tolerant Networks (Delay Tolerant Networks에서 속성정보 예측 모델을 이용한 상황인식 연결성 분석 기법)

  • Jeong, Rae-Jin;Oh, Young-Jun;Lee, Kang-Whan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제19권4호
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    • pp.1009-1016
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    • 2015
  • In this paper, we propose EPCM(Efficient Prediction-based Context-awareness Matrix) algorithm analyzing connectivity by predicting cluster's context data such as velocity and direction. In the existing DTN, unrestricted relay node selection causes an increase of delay and packet loss. The overhead is occurred by limited storage and capability. Therefore, we propose the EPCM algorithm analyzing predicted context data using context matrix and adaptive revision weight, and selecting relay node by considering connectivity between cluster and base station. The proposed algorithm saves context data to the context matrix and analyzes context according to variation and predicts context data after revision from adaptive revision weight. From the simulation results, the EPCM algorithm provides the high packet delivery ratio by selecting relay node according to predicted context data matrix.

An Analysis for Transferring Connectivity at Incheon international Airport (허브공항의 환승연계성 분석연구(인천국제공항을 대상으로))

  • Park, Yong-Hwa;Kim, Seong-Yeong;Kim, Jung-Yeop
    • Journal of Korean Society of Transportation
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    • 제24권6호
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    • pp.75-85
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    • 2006
  • Recently. large number of countires have been focused on the construction of container seaport and hub airport to enrole as the center of logistics. In particular, the East Asian nations have been enhanced their airports' facilities in order to accommodate for demand of global market environment. In Korea, Incheon International Airport (ICN) was opened in 2001 to take leading role as the Northeast Asian main hub airport. The purpose of this research is to analyze the transferring connectivity at ICN. To analyze its connectivity, this research has been applies two methodologies ; wane structure and minimum or maximun connection time analysis It has analyzed the temporal configuration as the frequency and quality of indirect connections offered by an airline by adopting a wave-system structure in the airline flight schedule. As an empirical analysis, it also calculated the minimum and maximum connection time adopting Korean Air's flight information.

Explicit Categorization Ability Predictor for Biology Classification using fMRI

  • Byeon, Jung-Ho;Lee, Il-Sun;Kwon, Yong-Ju
    • Journal of The Korean Association For Science Education
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    • 제32권3호
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    • pp.524-531
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    • 2012
  • Categorization is an important human function used to process different stimuli. It is also one of the most important factors affecting measurement of a person's classification ability. Explicit categorization, the representative system by which categorization ability is measured, can verbally describe the categorization rule. The purpose of this study was to develop a prediction model for categorization ability as it relates to the classification process of living organisms using fMRI. Fifty-five participants were divided into two groups: a model generation group, comprised of twenty-seven subjects, and a model verification group, made up of twenty-eight subjects. During prediction model generation, functional connectivity was used to analyze temporal correlations between brain activation regions. A classification ability quotient (CQ) was calculated to identify the verbal categorization ability distribution of each subject. Additionally, the connectivity coefficient (CC) was calculated to quantify the functional connectivity for each subject. Hence, it was possible to generate a prediction model through regression analysis based on participants' CQ and CC values. The resultant categorization ability regression model predictor was statistically significant; however, researchers proceeded to verify its predictive ability power. In order to verify the predictive power of the developed regression model, researchers used the regression model and subjects' CC values to predict CQ values for twenty-eight subjects. Correlation between the predicted CQ values and the observed CQ values was confirmed. Results of this study suggested that explicit categorization ability differs at the brain network level of individuals. Also, the finding suggested that differences in functional connectivity between individuals reflect differences in categorization ability. Last, researchers have provided a new method for predicting an individual's categorization ability by measuring brain activation.

Bayesian Filter-Based Mobile Tracking under Realistic Network Setting (실제 네트워크를 고려한 베이지안 필터 기반 이동단말 위치 추적)

  • Kim, Hyowon;Kim, Sunwoo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • 제41권9호
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    • pp.1060-1068
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    • 2016
  • The range-free localization using connectivity information has problems of mobile tracking. This paper proposes two Bayesian filter-based mobile tracking algorithms considering a propagation scenario. Kalman and Markov Chain Monte Carlo (MCMC) particle filters are applied according to linearity of two measurement models. Measurement models of the Kalman and MCMC particle filter-based algorithms respectively are defined as connectivity between mobiles, information fusion of connectivity information and received signal strength (RSS) from neighbors within one-hop. To perform the accurate simulation, we consider a real indoor map of shopping mall and degree of radio irregularity (DOI) model. According to obstacles between mobiles, we assume two types of DOIs. We show the superiority of the proposed algorithm over existing range-free algorithms through MATLAB simulations.

Facilitating Conditions and the Use of Plagiarism Detection Software by Postgraduates of the University of Ibadan, Oyo State, Nigeria

  • Oluwaseun Jolayemi;Olawale Oyewole;Oluwatosin Oladejo
    • International Journal of Knowledge Content Development & Technology
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    • 제14권3호
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    • pp.39-57
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    • 2024
  • Plagiarism detection software is beneficial in detecting plagiarism in research works of postgraduate students. Despite the benefits of using plagiarism detection software, studies have revealed that most students, including postgraduates, do not use plagiarism detection software as expected. This could depend on the provision of facilitating conditions like internet connectivity, training opportunities and electricity. Thus, this study examined facilitating conditions and the use of plagiarism detection software among postgraduates of the University of Ibadan, Nigeria. A descriptive survey research design of the correlational type was used for this study, with a population of 2143 postgraduates. The multi-stage random sampling technique was used to determine the sample size of 242. The questionnaire was the research instrument, and data was analysed using descriptive statistics. Results showed that most postgraduates agreed that the university provided facilitating conditions like internet connectivity. The majority of the respondents noted that they used Turnitin monthly. Most of the respondents noted that they used plagiarism detection software to paraphrase their work and check the correctness of the grammar in their documents. The most prominent challenges confronting plagiarism detection software use by most respondents were their inability to afford subscription payment to use the plagiarism detection software and slow internet connectivity. There was a significant positive relationship between facilitating conditions and the use of plagiarism detection software by the postgraduates of the University of Ibadan, Nigeria. Some of the recommendations for the institution's management include leveraging the vast network of alumni willing to give back to the institution and intervening in the provision of internet connectivity and electricity.

Corridor and Network Analyses of Forest Bird Habitats in a Metropolitan Area of South Korea (수도권 지역 산림성 조류 서식지의 통로와 연결망 분석)

  • Kang, Wanmo;Park, Chan-Ryul
    • Korean Journal of Agricultural and Forest Meteorology
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    • 제17권3호
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    • pp.191-201
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    • 2015
  • Measuring and mapping connectivity among habitats is a key component of sustainable urban planning and design process. In this study, we examined how functional corridors connect forest bird habitats in a metropolitan area of Korea using graph theory-based techniques. High-quality forest habitat was defined as a function of forest cover, presence of residential areas, and road networks. We then constructed a network of high-quality forest habitats using the FunConn (functional connectivity) tools, and computed metrics ($T_i$) of patch importance based on the minimum ($Q_1$) and the 25th percentile ($Q_{25}$) rank least-cost distance values. We investigated the relative influence of two values of patch importance on forest bird species richness. As a result, the patch importance index based on the $Q_{25}$ effective distance threshold was most positively correlated with species richness (P < 0.001) after controlling for the area effect. Thus, using the $Q_{25}$ effective distance threshold, we mapped not only the locations of important habitat patches and functional corridors, but also the network backbone of forest bird habitats. The network developed in this study can help guide urban planning for biodiversity conservation.

Regional Ecological Network Design for Wild Animals' Movement Using Landscape Permeability and Least-cost Path Methods in the Metropolitan Area of Korea (경관투과성 및 최소비용경로 분석을 통한 수도권 지역의 광역생태축 구축 연구)

  • Lee, Dong-Kun;Song, Won-Kyong;Jeon, Seong-Woo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • 제11권3호
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    • pp.94-106
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    • 2008
  • As populations inhabiting in natural ecosystem are fragmented by artificial barriers and habitats are destructed by development, extinction possibility of species is getting higher. It is necessary to design and to manage conservation areas and corridors considering animals' movement and migration for sustainable species diversity in present circumstances. 'Least-cost modeling' is one commonly employed approach in which dispersal costs are assigned to distinct habitat types and the last-costly dispersal paths among habitat patches are calculated using a geographical information system (GIS). This study aims to design ecological corridor using least-cost path method and to apply it to a regional ecological network considering movability of medium-large size mammals. This study was carried out over the metropolitan area, which has been deforested by rapid urbanization. Nevertheless there is connected with Gangwon province, Baekdudaegan mountain range and DMZ, considered where many forest species can migrate to this region. This study employs such an approach to develop least-cost path models for medium-large size mammals, have inhabited for this entire region. Considering those species, two forest areas as a source of species supply and forest areas more than 1,000ha are selected as focal forest areas. Movement and migration paths from species supply sources to focal forest areas are calculated by applying landscape permeability theory using land cover map, road density map and land slope map. Results showed least-cost paths from species supply sources to focal forest areas on two species. Wildcat and roe deer are different in some least-cost paths caused by their landscape permeability but paths show generally same specifics. The result of considering regional distribution of expected movement and migration paths to regional ecological network, low altitude mountains of western metropolitan area are evaluated important area for species connectivity. In national or regional levels ecological connectivity is essential to promote species diversity and to preserve integrated ecosystem. This study concludes that developing least-cost models from similar empirical data could significantly improve the utility of these tools.

Hierarchical Folded Hyper-Star Network(HFH): A New Interconnection Network Based on Folded Hyper-Star Network (계층적 Folded 하이퍼-스타 연결망(HFH): Folded 하이퍼-스타 연결망을 기반으로 하는 새로운 상호연결망)

  • Kim, Jong-Seok;Lee, Hyeong-Ok
    • The KIPS Transactions:PartA
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    • 제15A권2호
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    • pp.95-100
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    • 2008
  • In this paper, we propose a new interconnection network topology, hierarchical folded hyper-star network HFH($C_n,\;C_n$), which is based on folded hyper-star network. Our results show that the proposed hierarchical folded hyper-star network performs very competitively in comparison to folded hyper-star network and hierarchical network HCN(m,m), HFN(m,m) have been previously proposed, when diameter ${\times}$ degree is used as a network cost measure. We also investigate various topological properties of HFH($C_n,\;C_n$) including connectivity, routing algorithm, diameter, broadcasting.