• Title/Summary/Keyword: change of communication environment

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Performance and Multi-hop Transmission Tests for Vehicular Communication Systems in Real Road Environments (실제 도로환경에서 차량 통신시스템의 성능 및 멀티홉 전송시험)

  • Song, Jung-Hoon;Lee, Jae-Jeong;Jung, Seung-Wan;Seo, Dae-Wha
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.13 no.1
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    • pp.35-45
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    • 2014
  • The driving environment of the vehicle has characteristics that the change of position, velocity and distance between vehicles is severe. The performance test of system must be carried out in the real road environments with consideration of the driving environment of vehicles to measure the performance correctly because the performance of vehicular communication systems is affected by the driving conditions of the vehicle. In this paper, we propose the test methods of V2V/V2I performance and V2V multi-hop transmission function and present the test results measured by the vehicular communication systems already developed. In the test result, we confirmed the fact that the distance of communication devices and the driving direction of vehicle are affecting the communication performance. We also confirmed the multi-hop transmission function using the driving vehicle in the limited area as the proposed test method.

Estimation of Channel States for Adaptive Code Rate Change in DS-SSMA Communication Systems: Part 1. Estimation of Effective Number of Users

  • Youngkwon Ryu;Iickho Song;Taejoo Chang;Kim, Suk-Chan
    • Journal of Electrical Engineering and information Science
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    • v.1 no.1
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    • pp.17-22
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    • 1996
  • Adaptive code rate change schemes in DS-SSMA systems are proposed. In the proposed schemes, the error correcting code rate is changed according to the channel states. Two channel states having significant effects on the bit error probability are considered: one is the effective number of users, and the other is the fading environment. These channel states are estimated based on retransmission requests. The criterion for the change of the code rate is to maximize the throughput under given error bound.

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Design and Implementation of a Mobile Middleware System for Mobile Business (모바일 비즈니스를 위한 모바일 미들웨어 시스템 설계 및 구현)

  • Lee, Il-Joo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39B no.2
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    • pp.102-113
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    • 2014
  • Present communication and network environment have been moving rapidly toward wireless and mobile base from existing wired internet base. This change of trend influences greatly on business methods accordingly. Therefore many enterprises are trying hard to adopt mobile business in order to gain competitive edge of their products and they are in need of more effective and stable mobile solutions. However, the method of establishing optimal mobile computing environment and how to handle existing business process and use vast amount of database are still needed. Therefore this paper tries to realize a mobile middleware system as a mobile business establishment supporting tool that could link various computational resource on wired internet with wireless LAN, mobile phone network, and mobile devices. To accomplish that specific goal, this paper provides a powerful tool of mobile and wireless application data access that could expand the line of business already set up in general enterprises easily and rapidly into mobile environment. When this suggested solution is applied in the field of industry, it can economically change legacy business process into mobile environment without having to change existing logic and resources at all.

Design and Implementation of Wireless Lighting LED Controller using Modbus TCP for a Ship (Modbus TCP를 이용한 선박용 무선 LED 제어기의 설계 및 구현)

  • Jeong, Jeong-Soo;Lee, Sang-Bae
    • Journal of Navigation and Port Research
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    • v.41 no.6
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    • pp.395-400
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    • 2017
  • As a serial communications protocol, Modbus has become a practically standard communication protocol and is now a commonly available means of connecting industrial electronic devices. Therefore, all devices can be connected using the Modbus protocol with the measurement and remote control on ships, buildings, trains, airplanes and more. The existing Modbus that has been used is based on serial communication. Modbus TCP uses Ethernet communication based on TCP / IP which is the most widely used Internet protocol today; so, it is faster than serial communication and can be connected to the Internet of Things. In this paper, we designed an algorithm to control LED lighting in a wireless Wi-Fi environment using the Modbus TCP communication protocol, and designed and implemented a LED controller circuit that can check external environmental factors and control remotely through the integrated management system of a ship. Temperature, humidity, current and illuminance values, which are external environmental factors, are received by the controller through the sensors, and these values are communicated to the ship's integrated management system via the Modbus protocol. The Modbus can be connected to Master devices via TCP communication to monitor temperature, humidity, current, illuminance status and LED output values, and also users can change the RGB value remotely in order to change to the desired color. In addition, in order to confirm the implementation of the controller, we developed a simulated ship management system to monitor the temperature, humidity, current and illumination conditions, and change the LED color of the controller by changing the RGB value remotely.

A Study on Relationship between Interactive in Media Art and Ubiquitos Space (미디어 아트의 인터랙티브 개념과 유비쿼터스 공간과의 관계성 연구)

  • Jung, Jae-Won;Kim, Moon-Duck
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2006.11a
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    • pp.141-145
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    • 2006
  • The development of information & communication technology in 21st century along with the mass media In 20th century, the influence of state-of-art culture in our society rapidly increased in these days. This state-of-art culture makes the world becomes single-channeled by network, and there is a big change not only in human life but also in concept and understand for art and space. The development of digital paradigm and media technology is exerting a strong influence on the Ubiquitous computing environment that is being drawn great interest. The ubiquitous is concerned as expansion of media art, and the interactive art which is part of media art has the similarity with the ubiquitous computing environment. In this study, the possibility of connection between the territory of ubiquitous environment which is recently focused and has strong interrelation feature, and the territory of interacting will be examined. Furthermore, possibility of new space design work through seeking the possibility of connection between two territories will be estimated.

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A Study for Classification of Types about Museum Exhibition Medium in View of Information Design (정보디자인의 관점에서 본 박물관 전시매체의 유형분류에 관한 연구)

  • Kim Kyung-Mi
    • Korean Institute of Interior Design Journal
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    • v.14 no.6 s.53
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    • pp.252-259
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    • 2005
  • A modern museum has been changed from a passive place for simply exhibiting arts and antique collections to an interactive place for learning and experiencing culture and information. Such a functional change of the modern museum requires not only reorganizing fundamental characteristics of the modern museum, but also reforming organization of management teams, changing attitudes of staffs and assigning new roles to staffs for accepting the new thought and approach of visitors. That is, the function of the modem museum is not limited to collect arts and antique collections. The fundamental change of the modern museum further requires using the collections as a tool or a medium to provide a cultural exchange between the visitors and the museum, and to give new experience and information to the visitors. After proposing discussion that ' how, what, who is related to the museum? ', the way of thinking the museum is changed from ' collection ' to ' communication '. The change of the modern museum improves an educational role of the museum, and makes the museum as a communicator exchanging information and experience with visitors. In the last analysis, the modern museum is not just an exhibition medium that simply transfers information of the exhibition mediums to public. The modem museum is also a communication medium in order to collect information and transfer the collected information to the visitors. That is, the modern museum should provide various exhibition and communication mediums to the visitors for exchanging information and cultural experience. Therefore, the modern museum requires additional functions processing information suitable to the present environment and level of the museum, and transferring the information to public.

Intention-awareness Communication System for Future Mobile Terminal with Flexible Shape Change (가변 형태의 미래형 단말기를 위한 의도인식 통신시스템)

  • Cho, Myeon-Gyun;Yoon, Dal-Hwan;Choi, Hyo-Sun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.6
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    • pp.2720-2728
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    • 2012
  • Recently flexible mobile terminals which can freely change the shape of their device are coming out with the development of the flexible display, high capacity memory and system integration technology. The display and the antenna configuration of the future terminals will be altered according to the QoS (quality of service) and the communication environment of users. In particular, we present the new emergence of a multimedia language for human and system to communicate over subjective concepts, intention of users. The intension of users is expressed by changing the shape of their mobile terminal. In addition, antenna configuration is also related to shape of terminal and QoS of users. Therefore, we set up a specific usage scenarios for future mobile terminals and propose an adaptive MIMO (multiple-input multiple-output) schemes that can maximize channel capacity and fit to QoS of users simultaneously.

Effective Marketing Strategies for Electronic Commerce Activation (전자상거래 활성화를 위한 효율적 마케팅전략)

  • Lee, Seung-Hee;Cho, Jae-Wan
    • Journal of Digital Convergence
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    • v.2 no.2
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    • pp.9-28
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    • 2004
  • The purpose of this study is explore the changes of environment in terms of diffusion of EC and to present effective marketing strategies for Electronic Commerce Activation. This paper focuses on the customer management, Real-Time Responding, and market strategies in Electronic Commerce. EC(Electronic Commerce) that out of the evolution of Internet technology gets a corporation changes to survive in 21st century. So the corporation must set the strategy to fit a Internet focused society. This paper is focusing the analysing the difference between the e-marketing and traditional marketing and proposing the new strategical marketing mix. On the Electronic Commerce, the 6Cs of marketing - Contents, Community, Commerce, Connection, Communication, Customizing - are being played out quite differently than they normally are off-line. In conclusion, the change in Electronic Commerce environment results in (1) redefinition of customer group, (2) different marketing strategies to fit in Electronic Commerce environment, and (3) changes in customer management, promotion strategy, advertizing appeal.

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Launch Environment Test Results of Koreasat-3 (무궁화위성 3호 발사환경시험 결과분석)

  • Yang, Koon-Ho;Choi, Seong-Bong;Kim, Wone-Chul;Kim, Seong-Joong;HwangBo, Han
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1252-1258
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    • 2000
  • Koreasat-3 was successfully launched by an Ariane IV launch vehicle on September 5, 1999. Although the primary purpose of the satellite is to replace Koreasat-l, it also can extend its communication service coverage over the Asia-Pacific region. A spacecraft is subjected to severe dynamic loads during launch period. To verify the safety of spacecraft under the launch environment, dynamic tests should be performed such as sine sweep, acoustic and separation shock tests. This paper presents the launch environment test results of Koreasat-3. A total of 188 acceleration responses was measured and compared with the design requirements of components and spacecraft. Dynamic characteristic change was also investigated by comparing between low-level pre/post vibration results. From the review of test results, it is concluded that Koreasat-3 was designed and manufactured with the margin of safety enough to survive the launch loads of Ariane IV.

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Reconfigurable Position Control of Unmanned Expedition Vehicles under the Open Control Platform based Ubiquitous Environment (유비쿼터스 환경에서 개방형 제어 플랫폼에 기반한 무인탐사차량의 재형상 가능 위치제어)

  • Shim Duk-Sun;Yang Cheol-Kwan;Ah Kyu-Seob;Lee Joon-Hak
    • Journal of Institute of Control, Robotics and Systems
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    • v.11 no.12
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    • pp.1002-1010
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    • 2005
  • We study on the implementation of reconfigurable position control system which is based on Open Control Platform(OCP) for Unmanned Expedition Vehicles(UEV) in ubiquitous environment. The control system uses hierarchical control structure and OCP structure which contains three layers such as core OCP, reconfigurable control API(Application Programmer Interface), generic hybrid control API. The goal of our research is to implement an UEV control system using advanced software technology. As a specific control problem, we study a transition management problem between PID control and neural network control depending on fault or parameter change of the plant, i.e., UEV. The concept of the OCP-based software-enabled control can provide synergy effect by the integration of software component, middleware, network communication, and control, and thus can be applied to various systems in ubiquitous environment.