• 제목/요약/키워드: networking system

검색결과 1,096건 처리시간 0.026초

KNX-ZigBee 게이트웨이의 설계 및 구현 (Design and Implementation of KNX-ZigBee Gateway)

  • 이우석;홍승호
    • 제어로봇시스템학회논문지
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    • 제17권7호
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    • pp.720-729
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    • 2011
  • The demand for wireless technology in home automation systems has recently been increasing due to several advantages such as installation cost reduction, easy placement, easy extension, aesthetic benefits, and mobile device connectivity. Among the many wireless technologies, ZigBee is one of the most useful for home automation; a wireless home networking system can be configured using ZigBee alone. Compatibility with conventional home networking systems that are based on wired media, however, is not supported. KNX is a mature protocol for wired media that is recognized as an international standard. This paper proposes a KNX-ZigBee gateway to interface between KNX and ZigBee systems and thereby enable integration of wired and wireless home automation systems.

Marketer-Generated Content Sharing Among Social Broadcasting Users: Effects of Intrinsic Motivations, Social Capital and the Moderating Role of Prevention Focus

  • Li, Yuhao;Wang, Kanliang
    • Asia pacific journal of information systems
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    • 제25권4호
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    • pp.719-745
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    • 2015
  • Social networking services provide individuals with an easy approach for exchanging messages with others based on interpersonal relationships. However, why individuals spread marketer-generated content (MGC) in their online social circles remains unclear. Therefore, we develop a theoretical model to examine how social capital, intrinsic motivations, personal perceptions, past behavior, and personal traits influence MGC sharing behavior of social media users in micro-blogging context. Data collected from 319 social networking users support the proposed model. The results from partial least squares analyses show that enjoyment, perceived control, and outcome expectations are significant indicators of individual's MGC sharing intention in the social broadcasting environment. Results also suggest that social capital, users' intention, and past behavior positively influence the MGC sharing behavior of users. Moreover, individual prevention pride exhibits a significant interaction effect on the relationships between users' MGC sharing and its antecedents. Implications for research and practice are discussed.

화상처리 및 무선네트워크를 이용한 무인 측정 지점에서의 원격 계측 자동화에 관한 연구 (A Study on the Automatic Measurement at an Unmanned Measuring Station Using Image Processing and Wireless Networks)

  • 이한준;차명석;이충훈
    • 한국공작기계학회논문집
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    • 제16권3호
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    • pp.15-22
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    • 2007
  • An automatic measurement system which collects experimental data at an unmanned station where the networking to the internet could not be accessed was developed. With a Robo-rail accessing to the unmanned station, wireless local networking between server PC at the Rob-rail and client PC at the unmanned station is possible within 30 m from an access point equipment located at the unmanned station. An algorithm for transferring the data file which is saved in the client PC at the unmanned station to the server PC in the Robo-rail was proposed. IEEE-1394 camera was used to collect the data at the client PC. An extracting program from the IEEE-1394 captured images to character data and number data was developed using image processing technique, which drastically reduces the size of data file comparing to that of the raw image file.

A Novel High Speed Frequency Sweeping Signal Generator in X-band Based on Tunable Optoelectronic Oscillator

  • Sun, Mingming;Chen, Han;Sun, Xiaohan
    • Current Optics and Photonics
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    • 제2권1호
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    • pp.53-58
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    • 2018
  • A novel X-band high speed frequency sweep signal generator based on a tunable optoelectronic oscillator (OEO) incorporating a frequency-swept laser is presented and the theoretical fundamentals of the design are explained. A prototype of the generator with tuning range from 8.8552 GHz to 10.3992 GHz and a fine step about 8 MHz is achieved. The generated radiofrequency signal with a single sideband (SSB) phase noise lower than -100 dBc/Hz@10KHz is experimentally demonstrated within the whole tunable range, without any narrow RF band-pass filters in the loop. And the tuning speed of the frequency sweep signal generator can reach to over 1 GHz/s benefiting from applying a novel dispersion compensation modular instead of several tens of kilometers of optical fiber delay line in the system.

Personal computer networking for concept understanding

  • Sakai, Y.;Kitazawa, M.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.624-629
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    • 1992
  • This paper deals with the architecture of an information processing model for the human concept understanding required in constructing intelligent man-machine interfaces. The architecture employed is a parallel processing by networking. For this purpose, personal computers are interconnected by LAN and are, in their roles, divided into three levels. A concept has two aspects; i.e., language and image. In the present model, the system as the holistic whole of personal computers together with peripheral devices processes visual information in cognitive level, searching for feasible solutions from a variety of aspects. An image inputted through peripheral systems is categorized and matched with those ever experienced with the aid of that categorization, and thus an image is identified.

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Reduced Complexity Signal Detection for OFDM Systems with Transmit Diversity

  • Kim, Jae-Kwon;Heath Jr. Robert W.;Powers Edward J.
    • Journal of Communications and Networks
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    • 제9권1호
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    • pp.75-83
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    • 2007
  • Orthogonal frequency division multiplexing (OFDM) systems with multiple transmit antennas can exploit space-time block coding on each subchannel for reliable data transmission. Spacetime coded OFDM systems, however, are very sensitive to time variant channels because the channels need to be static over multiple OFDM symbol periods. In this paper, we propose to mitigate the channel variations in the frequency domain using a linear filter in the frequency domain that exploits the sparse structure of the system matrix in the frequency domain. Our approach has reduced complexity compared with alternative approaches based on time domain block-linear filters. Simulation results demonstrate that our proposed frequency domain block-linear filter reduces computational complexity by more than a factor of ten at the cost of small performance degradation, compared with a time domain block-linear filter.

Wide-Area SCADA System with Distributed Security Framework

  • Zhang, Yang;Chen, Jun-Liang
    • Journal of Communications and Networks
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    • 제14권6호
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    • pp.597-605
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    • 2012
  • With the smart grid coming near, wide-area supervisory control and data acquisition (SCADA) becomes more and more important. However, traditional SCADA systems are not suitable for the openness and distribution requirements of smart grid. Distributed SCADA services should be openly composable and secure. Event-driven methodology makes service collaborations more real-time and flexible because of the space, time and control decoupling of event producer and consumer, which gives us an appropriate foundation. Our SCADA services are constructed and integrated based on distributed events in this paper. Unfortunately, an event-driven SCADA service does not know who consumes its events, and consumers do not know who produces the events either. In this environment, a SCADA service cannot directly control access because of anonymous and multicast interactions. In this paper, a distributed security framework is proposed to protect not only service operations but also data contents in smart grid environments. Finally, a security implementation scheme is given for SCADA services.

Cooperation Method for Cellular Communication Systems

  • Kim, Eung-Sun;Kim, Young-Doo;Park, Sang-Kyu
    • 한국통신학회논문지
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    • 제32권12A호
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    • pp.1251-1259
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    • 2007
  • A scheme for selecting the mode with the maximum system capacity is proposed for cooperative relaying. Three possible modes are presented based on decode-and-forward relaying, and the time required by each mode is evaluated. Based on these results, a method is then developed for selecting the optimal mode with the minimum time duration (or maximum channel capacity). Computer simulations confirm that the optimal mode outperforms the other modes.

A Study on the Globaization Starategy of Korean Textile Design

  • Lee, Eun-Oak
    • The International Journal of Costume Culture
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    • 제4권1호
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    • pp.61-70
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    • 2001
  • This study discuses the strategies for the reestabisgment of Korean textile industry by emphasizing the area of textile design which plays an important role in developing textile materials. The textile industry in Korea has been in stagnancy for a long period of time and appears to find no answer to the problem. The big part of the problem is that the industry itself does not realize the importance of textile design and its management does not understand its critical role in contributing the growth of the industry. To develop textile design, first, we need to foster textile designers who have the creativity, an understanding of international trend and a mind f management. This can be achieved through an education system with a close tie to the textile industry. Second, we need to globalize our textile design in three aspects : design, technology and marketing. A balanced and harmonized progression of these three aspects will guarantee a successful globalization of textile design. This progression, however, demands creativity, identity, and interaction on the design side, digital and networking on the technology side, and culture marketing, brand value, and global agent networking on the marketing side.

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