• Title/Summary/Keyword: network theory

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Mobile Source Emissions Estimates for Intra-zonal Travel Using Space Syntax Analysis (공간 구문론을 이용한 존내 자동차 배출량 추정 모형)

  • LEE, Kyu Jin;CHOI, Keechoo
    • Journal of Korean Society of Transportation
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    • v.34 no.2
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    • pp.107-122
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    • 2016
  • This study aims to develop a framework to estimate mobile source emissions with the macroscopic travel demand model including enhanced estimates of intra-zonal travel emissions using Space Syntax analysis. It is acknowledged that "the land-use and transportation interaction model explains the influence of urban structure on accessibility and mobility pattern". Based upon this theory, the estimation model of intra-zonal travel emissions is presented with the models of total travel distance, total travel demand, and average travel speed of intra-zonal trips. Thess statistical models include several spatial indices derived from the Space Syntax analysis. It explains that urban spatial structure is a critical factor for intra-zonal travel emissions, which is lower in compact zone with smaller portion of land area, lower sprawl indicator, and more grid-type of road network. Also the suggested framework is applied in the evaluation of the effectiveness of bicycle lane project in Suwon, Korea. The estimated emissions including intra-zonal travel is as double as the results only with inter-zonal demands, which shows better performance of the suggested framework for more realistic outcomes. This framework is applicable to the estimation of mobile source emissions in nation-wide and the assessment of transportation-environment policies in regional level.

A Study on Business Types of IoT-based Smarthome: Based on the Theory of Platform Typology (IoT 기반 스마트홈 비즈니스 유형 연구: 플랫폼유형론을 근간으로)

  • Song, Minzheong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.2
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    • pp.27-40
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    • 2016
  • This paper aims to analyze the business types of 237 IoT based smart home companies in the world (launched during 1999~2014) which got global investment last few years. For this, the previous literatures trying to analze technology and service types of smart home are searched and the typology of the platform is discussed. Based on it, this research conceptualizes an analysis framework that includes three areas of smart home like home automation, home security, and energy efficiency with the three platform types like product, software, and service. This study concludes that the development of business type for IoT based smart home ecosystem is from the product to software and it can be a platform or not. In current status, there are a few platforms of product and software, but in the device management (16%) and thermostat (11%), companies are persuing more platform like. It is difficult to find the service platform in overall areas, for application based service has a few attractions in the investment market due to the lack of cloud infrastructure and data analytics. The following three are the implication to domestic market: 1) More active offering of API and SDK, 2) more active introduction of wireless Intenet network protocols, and 3) more active interoperability efforts and alliance activities are needed.

Structure of Data Fusion and Nonlinear Statistical Track Data Fusion in Cooperative Engagement Capability (협동교전능력을 위한 자료융합 구조와 비선형 통계적 트랙 융합 기법)

  • Jung, Hyoyoung;Byun, Jaeuk;Lee, Saewoom;Kim, Gi-Sung;Kim, Kiseon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.1
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    • pp.17-27
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    • 2014
  • As the importance of Cooperative Engagement Capability and network-centric warfare has been dramatically increasing, it is necessary to develop distributed tracking systems. Under the development of distributed tracking systems, it requires tracking filters and data fusion theory for nonlinear systems. Therefore, in this paper, the problem of nonlinear track fusion, which is suitable for distributed networks, is formulated, four algorithms to solve the problem of nonlinear track fusion are introduced, and performance of introduced algorithms are analyzed. It is a main problem of nonlinear track fusion that cross-covarinaces among multiple platforms are unknown. Thus, in order to solve the problem, two techniques are introduced; a simplification technique and a approximation technique. The simplification technique that help to ignore cross-covariances includes two algorithms, i.e. the sample mean algorithm and the Millman formula algorithm, and the approximation technique to obtain approximated cross-covariances utilizes two approaches, by using analytical linearization and statistical linearization based on the sigma point approach. In simulations, BCS fusion is the most efficient scheme because it reduces RMSE by approximating cross-covariances with low complexity.

A Study on the SNS Advertising's Word-of-Mouth Constraint Factors in the Social Network Service (소셜 네트워크 서비스에서 SNS광고 구전 제약요인에 대한 연구)

  • Yun, Dae-Hong;Kang, Yong-Soo
    • Management & Information Systems Review
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    • v.35 no.1
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    • pp.69-84
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    • 2016
  • This study set the research model to examine the correlation between Word-of-Mouth constraint factors, efforts to negotiate pertaining to these, Flow and Word-of-Mouth intent based on the theory of leisure constrain when it comes to the correlation between consumers' Word-of-Mouth constraint factors and Word-of-Mouth. Correlation among the variables were verified in an empirical manner. Results of this study are summarized as follows. After verifying the hypotheses, all the hypotheses were adopted excluding the hypotheses of two results (Hypothesis 1, hypotheses 5). Detailed results regarding this are as follows. First, the following is the effect of the Intrapersonal Constraint and Word-of-Mouth constraint factors on the Word-of-Mouth constraint negotiation effort. Interpersonal Constraint and Structural Constraint exert positive (-) effect on the Word-of-Mouth constraint negotiation effort. In case of Intrapersonal Constraint, negative (-) effect was demonstrated. Thus, this was statistically significant although dismissed from hypothesis verification. Second, the following is the result of examining the structural correlation between Word-of-Mouth constraint negotiation effort, Flow and Word-of-Mouth. Word-of-Mouth constraint negotiation effort exerts positive (-) effect on the Flow, but it was not statistically effective in case of the Word-of-Mouth. Lastly, it is possible to see that the Flow plays the role of a medium since it exerted positive (-) effect on the Word-of-Mouth. Results of this study are expected to provide key theoretical and working level implications as well as general understanding of the Word-of-Mouth constraint factors, consumers' Flow and Word-of-Mouth.

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The Effect of SNS(Social Network Services) Quality on Customer Loyalty: Focus on the Mediated Moderation Effect of Customer Satisfaction by Trust (소셜네트워크서비스(SNS) 품질이 고객 충성도에 미치는 영향: 신뢰를 통한 고객 만족의 매개된 조절효과를 중심으로)

  • Park, Wonhee
    • Journal of Service Research and Studies
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    • v.3 no.1
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    • pp.17-31
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    • 2013
  • With the advent of smart phones, there are increasing demands from customers to connect to the social media services at any time and at any place without restraint. As a result, many foreign companies have lately been able to pursue two-way communication with customers through social media which has enabled them to see the reaction and the needs of customers immediately and respond timely. That is, they are actively engaged in the various marketing activities targeting customers using SNS. According to H. A. Simon's needle theory, it is efficient to make a decision within the bounded rationality due to the difficulty of collecting data in decision-making as well as the inability to collect all information because of limited time and money. If the information or the informant can be trusted, the customers would be able to make a quick decision and get higher satisfaction from it. Therefore, this study examines and thereby empirically demonstrates what role customers' trust plays in a company's marketing using SNS by exploring how trust condition works in the mediated model and, theoretically, intends to introduce an empirical methodology on more strictly mediated moderating effects and, in practice, revisit the role of trust on direct and indirect effect the SNS's quality has on the performance variables such as customer satisfaction and loyalty. This study thereby aims to provide a strategic tool for the companies that plan to use the SNS in developing marketing strategies.

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Railway Governance and Power Structure in China

  • Lee, Jinjing
    • International Journal of Railway
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    • v.1 no.4
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    • pp.129-133
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    • 2008
  • Over the last $15{\sim}20$years, many countries have adopted policies of railway privatization to keep up with increasing competition from road and air transport. Although each country and case has its own history, market characteristics, political context as well as administrative process, railway privatizations (including railway restructure, concession etc.) in the west usually are accompanied with the establishment of new regulatory regimes. Therefore, railway governance has been innovating towards an interaction of government, regulator, industry bodies, user groups, trade unions and other interested groups within the regulatory framework. However, it is not the case in China. Although China had seen a partial privatization in some branch lines and is experiencing a much larger-scale privatization by establishing joint-ventures to build and operate high-speed passenger lines and implementing an asset-based securitization program, administrative control still occupies absolutely dominant position in the railway governance in China. Ministry of Railway (MOR) acts as the administrator, operator as well as regulator. There is no national policy that clearly positions railway in the transportation network and clarifies the role of government in railway development. There is also little participation from interested groups in the railway policy making, pricing, service standard or safety matter. Railway in China is solely governed by the mere executive agency. Efficiency-focused economic perspective explanation is far from satisfaction. A wider research perspective from political and social regime is of great potential to better explain and solve the problem. In the west, separation and constrains of power had long been established as a fundamental rule. In addition to internal separation of political power(legislation, execution and jurisdiction), rise of corporation in the 19th century and association revolution in the 20th century greatly fostered the growth of economic and social power. Therefore, political, social and economic organizations cooperate and compete with each other, which leads to a balanced and resonable power structure. While in China, political power, mainly party-controlled administrative power has been keeping a dominated position since the time of plan economy. Although the economic reform promoted the growth of economic power of enterprises, it is still not strong enough to compete with political power. Furthermore, under rigid political control, social organizations usually are affiliated to government, independent social power is still too weak to function. So, duo to the limited and slow reform in political and social regime in China, there is an unbalanced power structure within which political power is dominant, economic power expanding while social power still absent. Totally different power structure in China determines the fundamental institutional environment of her railway privatization and governance. It is expected that the exploration of who act behind railway governance and their acting strength (a power theory) will present us a better picture of railway governance as a relevant transportation mode. The paper first examines the railway governance in China and preliminarily establishes a linkage between railway governance and its fundamental institutional environment, i.e. power structure in a specific country. Secondly, the reason why there is no national policy in China is explored in the view of political power. In China, legislative power is more symbolic while party-controlled administrative power dominates political process and plays a fundamental role in Chinese railway governance. And then, in the part three railway finance reform is analyzed in the view of economic power, esp. the relationship of political power and economic power.

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Arrhythmia Classification based on Binary Coding using QRS Feature Variability (QRS 특징점 변화에 따른 바이너리 코딩 기반의 부정맥 분류)

  • Cho, Ik-Sung;Kwon, Hyeog-Soong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.8
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    • pp.1947-1954
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    • 2013
  • Previous works for detecting arrhythmia have mostly used nonlinear method such as artificial neural network, fuzzy theory, support vector machine to increase classification accuracy. Most methods require accurate detection of P-QRS-T point, higher computational cost and larger processing time. But it is difficult to detect the P and T wave signal because of person's individual difference. Therefore it is necessary to design efficient algorithm that classifies different arrhythmia in realtime and decreases computational cost by extrating minimal feature. In this paper, we propose arrhythmia detection based on binary coding using QRS feature varibility. For this purpose, we detected R wave, RR interval, QRS width from noise-free ECG signal through the preprocessing method. Also, we classified arrhythmia in realtime by converting threshold variability of feature to binary code. PVC, PAC, Normal, BBB, Paced beat classification is evaluated by using 39 record of MIT-BIH arrhythmia database. The achieved scores indicate the average of 97.18%, 94.14%, 99.83%, 92.77%, 97.48% in PVC, PAC, Normal, BBB, Paced beat classification.

Design and Evaluation of a Buffering Patching Technique for VOD Systems (주문형 비디오 시스템을 위한 버퍼링 패칭 기법의 설계 및 평가)

  • 하숙정;배인한
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.10
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    • pp.523-532
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    • 2003
  • Video on Demand(VOD) services cause high resource consumption in a video seuer, because multimedia are characterized by continuous playback, a high bandwidth requirement, and long playback duration. Patching has been proposed to save the network I/O bandwidth of a video server. To achieve true VOD, patching uses multicasting to share video streams, thereby providing immediate VOD services to users without any service latency. A communication channel is used to either multicast the entire video as a regular channel or multicast only the leading portion of a video as a Patching channel. This paper Proposes a buffering patching technique that divides regular channels, as used in patching, into sub-regular channels and regular channels to shorten the holding time of the channels. In the proposed technique, the last portion of video data, corresponding to the size of the buffering window, is not transferred by sub-regular channels, but rather downloaded and buffered in the user buffer from the latest regular channel. When simulations were performed to compare the performance of the proposed technique with that of conventional patching, the results indicated that the proposed technique was superior in terms of the defection rate, average service latency, and fairness, although the amount of video data buffered at each user station was higher than that with patching.

The Aspectual Theory of the Cybercharacter (사이버캐릭터의 위상론)

  • 이선교
    • Archives of design research
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    • v.12 no.4
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    • pp.182-190
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    • 1999
  • There has been the rapid change of paradigm with the overflow of terms related to computers such as information, digital, cyber, virtual world and the change of time concept on the ground that it is common to change the world into virtual time. This study is about cybercharacters working in air-broadcasting with rapidly-developing internet, The cybercharacters including 3D animation developed from 2D animation are know to be manufactured with use of electronic mediun and computers and to exist in electronics. Though the emergence of the cybercharacters has a lot of gflnetic roots according to their objectives, they have in common that they are made by 3D graphics and they work in the virtual space, The great traits of the cybercharaters lie in the extension of interfacial function and ecological growth. In the cyberspace the interface, the meeting point between a computer and its users is the most important, The cybercharacters as medium providing new ruman interface become effective with growing interest in virtual reality, The cybercharacters also keep the ecological traits, They can also bring about added value with infusion of image and development of the network, These cybercharacters can also play the important parts in the continually developing cyberspace, The successful birth of the cybercharacter are based on, the technological power. assistance of fund and the ctrltural background, The information-entertainment of the cybercharacters functions well with the accompinimene of these three things, The cybercharacters can make a subject which keeps single issue as a central point of the virtual realty, The cybercharacters can also be connected with equity of "Korean knowledge information society" in the cultural rule of the internet and sociocul tural identity, identity.

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Applying TMO-Based Object Group Model to Area of Distributed Real-Time Applications and Its Analysis (분산 실시간 응용 분야에 TMO 기반 객체그룹 모델의 적용 및 분석)

  • 신창선;정창원;주수종
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.8
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    • pp.432-444
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    • 2004
  • In this paper, we construct the TMO-based object group model on distributed environment, and analyze and evaluate the executability for distributed real-time service of our object group model by developing the distributed real-time application simulator applying the model. The Time-triggered Message-triggered Object(TMO) is a real-time server object having real-time property itself. The TMO-based object group is defined as a set of objects which logically reconfigured the physically distributed one or more TMOs on network by a given distributed application. For supporting group management of the server objects, the TMO-based object group we suggested provides the functions which register and withdraw the solver objects as a group member to an arbitrary object group, and also provides the functions which insert and delete the access rights of server objects from clients. Also, our model was designed and implemented to support the appropriate object selection and dynamic binding service for a single TMO as well as the duplicated TMOs, and to support the real-time scheduling service for the clients which are requesting the service. Finally, we developed the Defence System against Invading Enemy Planes(DSIEP) simulator as a practical example of distributed real-time application by applying our model, and evaluated the adaptability of distributed service strategies for the group components and the executability of real-time services that the TMO-based object group model provides.