• Title/Summary/Keyword: 통신장애

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Development of a Communication Unified AAC System (통신 융합형 보완·대체 의사소통 시스템 개발)

  • Kwak, S.W.;Kim, C.G.;Song, B.S.
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.5 no.1
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    • pp.65-70
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    • 2011
  • A communication is one of the most important factors for the human beings. Therefore, people who have some problems in communication need an Augmentative & Alternative Communication (AAC) intervention to live in the human societies and several AAC systems have been developed to help the people. Lately, smart-phone is widely used to people as a communication device which can connect between persons. It can provide many useful methods and Apps to the user. If the AAC system is unified to the smart-phone, it is very effective device to the people with disabled because they can reduce the excessive expense and easily accommodate themselves to the AAC system. In this paper, an AAC program which is installed in the smart-phone or tablet PC is introduced. It has basic AAC solutions and can send SMS message to other people. We expect that the developed device can help the communication of the people with disabled and solve the social isolation of the disabled person.

Still image comunications on the internet using the wavelet image compression technique (웨이블릿 영상 압축 기법을 이용한 인터넷에서의 정지영상 서비스)

  • 신무균;정제창;김민구
    • Journal of Broadcast Engineering
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    • v.4 no.1
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    • pp.12-21
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    • 1999
  • Without a question. the most significant new medium for transmitting information is the Internet. Unfortunately. the multimedia elements that enrich our titles are extremely bulky. While the Internet hype is available in unlimited supply. Internet bandwidth and functionality of web browser are not making the net quite hospitable to multimedia data formats. In this thesis. for smoother and better communications over the net. a study is done on still image compression techniques. based on wavelet transform which is selected on MPEG-4 as a still image compression standard and a strong candidate for the JPEG-2000 standard. For Internet service. the study of plug-in programming and ActiveX control is implemented to enrich the functionality of web browser. As a result. the proposed still image service gives better image quality than current standard JPEG and does not yield to the common blocking artifacts.

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New Interface for Mobile UCC Services : Applying Tag and Multi-Display Button to Mobile Device (모바일 UCC 서비스를 위한 새로 인터페이스의 개발 : 태그와 멀티 디스플레이 버튼이 적용된 모바일 폰을 중심으로)

  • Kim, Seong-Woon;Lee, In-Seong;Lee, Ki-Ho;Jung, Seung-Ki;Kim, Jin-Woo;Park, Joon-Ah;Bang, Won-Chul;Choi, Chang-Kyu;Kim, Yeun-Bae;Kim, Sang-Ryong;Lee, Kwon-Ju
    • 한국HCI학회:학술대회논문집
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    • 2007.02a
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    • pp.16-24
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    • 2007
  • 모바일 폰은 최근 관심의 대상이 되고 있는 사용자 제작 컨텐츠 (User-Created Content: UCC)의 생산과 공유를 위한 중요한 수단이다. 또한 HSDPA나 4G와 같은 차세대 이동통신 기술은Flickr나 YouTube 등의 웹 사이트에서 제공되고 있는 UCC 서비스가 모바일 폰을 통해서도 더욱 활발히 이용될 수 있는 가능성을 제시하고 있다. 그러나 모바일 폰이 가지고 있는 작은 화면 크기와 불편한 입력 장치라는 기본적인 한계는 모바일 UCC 서비스의 성공에 큰 장애 요인으로 작용할 수 있다. 따라서 본 연구는 정보 구조 (Information Structure) 및 정보 시각화 (Information Visualization)와 관련된 기존 이론 및 연구들을 기반으로 4가지 다른 모바일 폰 인터페이스들을 개발하고, 사용자들의 모바일 폰을 통한 탐색적 UCC 서비스 사용을 지원하는데 어떠한 인터페이스가 더 적합한지 실험 방법론을 통해 검증하는 것을 기본 목적으로 한다. 본 연구를 위하여 개발된 인터페이스들은 컨텐츠 구조의 관점에서 폴더 기반 계층 구조 (Folder-Based Hierarchical Structure)이나 태그 기반 네트워크 구조 (Tag-Based Network Structure)를 가지고 있으며, 컨텐츠 시각화의 관점에서는 고정 버튼 (Fixed Buttons)이나 멀티 디스플레이 버튼 (Multi-Display Buttons)를 가지고 있다. 66명의 실험 참가자들을 대상으로 한 실험 결과, 사용자들은 탐험 지향적 탐색 과업 (Exploratory Browsing)에서 태그 기반 네트워크 구조 또는 멀티 디스플레이 버튼이 제공된 모바일 인터페이스에 대하여 상대적으로 더 높은 유용성, 즐거움, 만족도, 향후 사용의도 등을 나타내었다.

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S/W Watch-Dog method between dual CPU using different OS (이종 OS로 구동되는 Dual CPU 기반에서의 S/W Watch-Dog 기법)

  • You, Young-Eel;Chon, Byoung-Sil
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.2
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    • pp.34-39
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    • 2010
  • This paper proposes S/W Watch-Dog method between Dual CPU using the different OS. The proposed watch-dog method performs that it distinguishes the status of channel between dual CPU and status of processor itself. We find out the ideal value of threshold and priority for load test task. and we evaluate the accuracy of the proposed S/W Watch-Dog Method at the result of evaluation. We figure out that the accuracy of proposed method is higher than the accuracy of general S/W Watch-Dog Method in case of variable data rate. Therefore we confirm that the proposed Method has high accuracy of watch-dog function with the ideal value of threshold and priority for load test task through the performance evaluation.

A Novel Architecture for Dynamic Mobile Networks with IPv6-based Multiple Network Interfaces (IPv6 기반의 다중 네트워크 인터페이스를 갖는 새로운 동적 이동형 네트워크 아키텍쳐)

  • Kim Wan-Tae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.8 s.350
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    • pp.25-34
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    • 2006
  • In this paper DynaMoNET is suggested as a novel IPv6-based multi-homed mobile network architecture which is composed of nested mobile ad hoc networks dynamically coming together through wireless personal area networks. Each ad hoc network has a mobile router which may work as a root mobile router instead of fixed mobile routers in a DynaMoNET. A root mobile router provides the reliable Internet connectivity for the entire mobile network. This paper includes a innovative handover protocol for multi-homed mobile networks, network switchover algorithm considering multiple decision factors, root mobile router election process based on token-based algorithm fast root mobile router discovery algorithm and fault avoidance mechanism to support reliable Internet connectivity. Finally the system architecture of a mobile router is given in detail.

A Key Distribution Protocol for Secure Multicasting in Large Dynamic Groups (대규모 동적 그룹에서 안전한 멀티캐스트를 위한 키 분배 프로토콜)

  • Kim, Tae-Yeon;Kim, Young-Kyoon
    • The KIPS Transactions:PartC
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    • v.9C no.4
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    • pp.597-604
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    • 2002
  • Changing group key is necessary for the remaining members when a new member joins or a member leaves the group in multicast communications. It is required to guarantee perfect forward and backward confidentiality. Unfortunately, in large groups with frequent membership changes, key changes become the primary bottleneck for scalable group. In this paper, we propose a novel approach for providing efficient group key distribution in large and dynamic groups. Unlike existing secure multicast protocols, our protocol is scalable to large groups because both the frequency and computational overhead of re-keying is determined by the size of a subgroup instead of the size of the whole group, and offers mechanism to prevent the subgroup managers with group access control from having any access to the multicast data that are transfered by sender. It also provides security service for preserving privacy in wireless computing environments.

Study on Subsurface Collapse of Road Surface and Cavity Search in Urban Area (도심지 노면하부 지반함몰 및 공동탐사 사례 연구)

  • Chae, Hwi-Young
    • Tunnel and Underground Space
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    • v.27 no.6
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    • pp.387-392
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    • 2017
  • Recently, road cave-ins, also referred to as ground sinking, have become a problem in urban environments. Public utility facilities such as sewage pipelines, communications pipes, gas pipes, power cables, and other types of underground structures are installed below the roads. It was reported that cave-ins are caused by the aging and lack of proper maintenance of underground facilities, as well as by construction problems. A road cave-in is first initiated by the formation of cavities typically induced by the breakage of underground pipelines. The cavities then grow and reach the base of the pavement. The traffic load applied at the surface of the roads causes an abrupt plastic deformation. This type of accident can be considered as a type of disaster. A road cave-in can threaten both human safety and the economy. It may even result in the loss of human life. In the city of Seoul, efforts to prevent damage before cave-ins occur have been prioritized, through a method of discovering and repairing joints through the 3D GPR survey.

Design of Software Architecture for Integrating of Messages between Semiconductor Equipments (반도체 장비의 메시지 통합을 위한 소프트웨어 구조 설계)

  • Lim, Yong-Muk;Hwang, In-Su;Kim, Woo-Sung;Park, Geun-Duk
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.2 s.46
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    • pp.151-159
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    • 2007
  • It is very important to collect all production-related status values during the manufacturing process of semiconductor. The analysis results of the collected data can be used for the operation rate, fault diagnosis, process control and removal of predicted obstacles of equipments, eventually contributing to the improvement of production efficiency. For this propose. many IC makers have adopted EES(Equipment Engineering System). As the use of web has become a daily lift activity lately, it has been suggested to expand the scope of monitoring equipments using HTTP or SOAP protocols. To fulfill the web-based EES, EDA(Equipment Data Aquisition) should be facilitated first by integrating and standardizing various forms of messages generated from many different semiconductor equipments. In this paper, a method for integration between different types of information is suggested based on the analysis of various protocols used for the communication between semiconductor equipments. In addition, a software architecture to support the method is desisted.

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Development and Application of ATM Protocol Conformance Test System (ATM 프로토콜 적합성 시험시스템의 개발과 적용)

  • Gang, Seong-Won;Seo, Yeong-Su;Hong, Mi-Jeong;Yang, Jun-Hwan;Go, Il-Guk;Gang, Deuk-Yun;Yu, Sang-Jo;Lee, Chae-U;Kim, Myeong-Cheol
    • Journal of KIISE:Computing Practices and Letters
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    • v.5 no.4
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    • pp.498-506
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    • 1999
  • 본 논문에서는 ATM 통신프로토콜을 위한 자동시험시스템인 ACTS(ATM Conformance Test System)의 개발과 적용을 소개한다. ACTS는 ITU-T 또는 ATM Forum의 ATM 사용자-망 접속표준을 준용하는 ATM 단말과 망장비의 프로토콜적합성을 확인하는데 사용된다. 본 논문에서는 ACTS 개발에 사용된 방법을 소개한 뒤, ACTS를 실제 ATM 단말과 장비에 적용한 사례들을 소개한다. ACTS의 적용을 통하여 시험대상 장비들이 지닌 프로토콜구현상의 문제점을 파악하였고, 문제에 대한 원인분석을 수행하였다. 또한 이러한 문제점들이 상호운용에 미치는 장애를 예측함으로써, ACTS를 상호운용하는 ATM 장비를 확보하기 위한 유용한 도구로 사용할 수 있음을 보인다.Abstract This paper presents development and application of ACTS(ATM Conformance Test System), an automated test system for ATM protocols. ACTS is a test system that checks conformance of ATM terminal and network equipment implementing either ITU-T or ATM Forum user-network interface. This paper, after presenting the methodology and process used for developing ACTS, conducts case studies of its applications to real ATM equipment. By applying ACTS, we were able to detect numerous problems in protocol implementations of ATM equipment and analyse causes of the problems, thereby demonstrating the efficacy of ACTS as an efficient automated testing tool. Furthermore, by predicting the potential effects of the problems on interoperability, we show how ACTS can be used as a useful tool for ensuring interoperable ATM equipment.

Case Study on the Use of CCTV for Realtime Monitoring and Recommended Improvements (상시계측시스템 모니터링을 위한 CCTV 활용사례 및 개선방안 연구)

  • Bae, Sang-Woo;Lee, Jong-Hyun;Kim, Seung-Hyun;Koo, Ho-Bon
    • The Journal of Engineering Geology
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    • v.22 no.4
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    • pp.417-425
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    • 2012
  • CCTV cameras are used for surveillance and purposes of security, and can also be applied for monitoring infrastructure and equipment. In the Cut Slope Management System managed by KICT (Korea Institute of Construction Technology), cut slopes are continuously monitored using a real-time system, with CCTV cameras installed at 119 sites to detect slope activity. Here we compare CCTV images with displacement at three sites and perform a quantitative analysis. Methods for improving CCTV camera management and systems are also discussed with regard to communication, obstacles, and nighttime management.