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  • Title/Summary/Keyword: 통신장애

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Design and Implementation of Electrocardiogram Data Interpretation system using AdaBoost Algorithm (AdaBoost 알고리즘을 이용한 심전도 정보 판독 시스템의 설계 및 구현)

  • Lim, Myung-Jae;Hong, Jin-Kyoung;Kim, Kyu-Ho;Choi, Mi-Lim
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.2
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    • pp.129-134
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    • 2010
  • Diseases such as cardiovascular illnesses, according to the National Statistical Office opened reveals that 600-800 people were killed, blood pressure, arteriosclerosis, heart disease, stroke, etc. will be a flow of blood disorders that occur in cardiovascular illnesses today are fulfilling the Master / Slave samangryulin disease appears high. Died of cardiovascular disease also told them the correct first aid survival when patients are accounted for approximately 40% of emergency rapid response is required. Therefore, this paper, the weak classifier in the AdaBoost algorithm to generate a strong classifier by combining effects throughout the analysis to measure the ECG, and cardiovascular disease that occurred to you as soon as the emergency management system that can deliver on the proposed Desk was. The electrocardiogram data measured by the ZigBee-based sensors, communication devices and emergency transport for emergency alarms in the determination and monitoring of the management desk by providing health services to enable the delivery was fast.

Efficient and Scalable Overlay Multicast Mechanism for Real-time Tree Construction (효율적이고 확장성 있는 실시간 트리 구성을 위한 오버레이 멀티캐스트 메커니즘)

  • Nam, Yun-Seung;Im, Dong-Gee;Yang, Hyun-Jong;Nam, Ji-Seung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12B
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    • pp.1399-1406
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    • 2009
  • In the internet broadcast, efficient and scalable mechanism of multicast is needed for the communication between groups. Furthermore, Optimization of the multicast tree is required to improve the performance of overlay multicast. This optimization is well-known as NP-complete. If a node in the tree has limited out-degree, a user who wants to join the group has to find parent user who has already joined. In this paper, the users who want to join the group need to setup their level using delay test from source node. And then new users can find candidate parent nodes effectively using ACK-SEND approach and take proper position by comparing level. The closer node of the user to root node should be located in lower level. Also, even if a barrier is caused, fast recovery will be guaranteed using ACK-SEND approach. Through this, the newcomer node can fine their location in the multicast tree and join the group fast and effectively.

Low Complexity Bit Loading Algorithm with Power-constraint for OFDM-based Wireless Sensor Communication (OFDM 기반 무선 센서 망에서 에너지 제한을 고려한 복잡도 낮은 비트 할당 알고리즘)

  • Oh, Seoung-Youl;Ko, Hyeon-Mok;Kwon, Soon-Mok;Kim, Chee-Ha
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12B
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    • pp.1483-1490
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    • 2009
  • Orthogonal frequency division multiplexing (OFDM) has been investigated as an enabling technology for future wireless communications such as ad hoc, mesh and sensor networks. However, prior works on bit-loading lack consideration of the constraints on energy and computing facility in sensor networks. In this paper, we suggest an adaptive bit allocation algorithm for a frequency selective fading channel environment which exploits channel state information obtained through a feedback channel. The proposed algorithm significantly reduces computational complexity and satisfies the power budget. Also, its throughput is comparable to the optimum solution. Simulation results support the claim stated.

Handover performance evaluation by a IEEE 802.11p based handover algorithm and its parameter under high-speed driving environments (고속주행환경에서 IEEE802.11p 기반 통신 핸드오버 알고리즘 파라미터 값에 따른 핸드오버 성능 분석)

  • Song, Yoo-Seung;Oh, Hyun-Seo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.12 no.5
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    • pp.52-60
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    • 2013
  • ITS technologies are in the research and development around the world as a solution for maximizing the efficiency of the existing road infrastructure, solving the complex traffic problems and providing the convenient driving services. The core of these ITS technologies is to provide the information for the requesting users in fast and accurate way from the server. In real driving conditions, there are many communication barriers around the vehicles and the base stations so that an accurate and robust handover technology is needed in order to ensure seamless ITS services. This paper introduced an WAVE handover algorithm implemented in a real communication device and five parameters mainly affecting the handover performance are evaluated. The handover performance is measured by changing the parameter values at a highway testbed. The test results show that the handover algorithm parameter values should be configured carefully to remove the handover ping-pong problems.

A Study on the Electromagnetic Wave Absorption Properties by the Composition Ratio and Sintering Condition of NiCuZn Ferrite (NiCuZn 페라이트의 조성 및 소결조건에 따른 전자파흡수 특성에 관한 연구)

  • 이영구;박찬규;이문수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.5
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    • pp.994-1000
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    • 2001
  • With the development of electromagnetic communication technology and increased use of electromagnetic wave, the countermeasure of EMI(Electromagnetic Interference) becomes more important socially, and interest for the electromagnetic wave absorber has also increased. In this paper, we have studied characteristics of frequency dependency on complex permittivity and complex permeability according to the changes of composition rate and sintering temperature of NiCuZn ferrite also known as electromagnetic wave absorber and further looked into effect of electromagnetic wave absorption properties. From the measurement where the composition of Fe2O3 and ZnO of NiCuZn ferrite was fixed at 49 and 34 mol% respectively while composition of NiO and CuO has been varied at each test, we found out that Initial permeability and permittivity were high and the absorbing ability of electromagnetic wave recorded best with losstangent(=\mur"/\mur) displays more than 1 within the frequency band of 2MHz~9.5MHz when the composition ratio of NiO was ranged around 8.5~9.5 mol% and the sintering temperature was 1080C.TEX>.

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A Secure Telemedicaine System in Smart Health Environment using BYOD (BYOD를 활용한 스마트헬스 환경에서 안전한 원격의료 시스템)

  • Cho, Young-bok;Woo, Sung-hee;Lee, Sang-ho;Park, Jong-bae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.10
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    • pp.2473-2480
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    • 2015
  • In telemedicaine, people can make their health checked at anywhere from temporal and spatial constraints and It's environment can provide continuous health information regardless of the location of customers through PCs and smart phones. In addition, personal health information collected utilizing the BYOD(bring your own device) is the most important factor data security and guaranteed personal privacy because it's directly connected to the individual's health and life. In this paper, we provide a signature of the private key encryption system and method for providing the security of personal health information data collected utilizing the BYOD. Against replay attacks and man-in-the-middle attacks on security issues that are emerging as a smart environmental health was used as the timestamp and signature methods. Proposed method provides encryption overhead, while a communication was lower compared to the pre-encrypted with a mean 1.499mJ 1.212mJ shown by simulation to respond quickly in an emergency situation to be about 59%.

The Study of Smart Navigation System development for blind people based on Cortex-A8 Platform include Digital Zoom (Digital Zoom기능을 포함한 Cortex-A8 Platform 기반의 시각장애인용 Smart Navigation System개발에 관한 연구)

  • Han, Seung-Hwan;Kim, Young-kil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.10a
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    • pp.289-292
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    • 2012
  • Presently, there is the blind of about 20~300,00 people including didn't register in Korea Usually, they used white stick when they walk outside. There is the blind receiving the help of the guide dog but a small number of blind uses due to many composite problems including the cost problem, and etc. Presently, the guidance service aid long for the blind which is commonly used adheres the RFID tag to the white stick. It remains at the level of the extent of making the cover block and RF communication by using this. The recognition distance is short. This is the actual condition in which it is difficult to determine the location of the clear obstacle and size and form, it doesn't become the help which is actually big in the walk of the blinds. Thus, in this paper, the investigation of 'Smart Portable Navigation System' development of the Cortex-A8 Platform base tries to be handled so that the blinds can walk easily.

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Performance Analysis of MC-DS-CDMA System Using a Interference Suppression Method in a Multipath Fading Channel (다중 경로 페이딩 채널 환경에서 다중반송파 DS-CDMA 시스템의 간섭 제거 성능 분석)

  • Park Tae-Yoon;Choi Jae-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.8B
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    • pp.745-751
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    • 2002
  • The performance of existing CDMA-type multiple access data transmission systems is limited by interferences due to adverse mobile communication channel characteristics. Among them, the multi-user interference becomes one of the major performance degradation factors because the signal-to-signal orthogonality can be easily perturbed when numerous user signals are distorted by multipath fading channels and mixed together. In order to enhance the performance of CDMA-type systems by suppressing the multi-user interference, we have adopted chip-based cyclic prefix insertion along with adaptive one-tap DFE equalization into MC-DS-CDMA, which is known for its robustness in the frequency selective multipath fading channel environment. In order to assess the performance of the proposed system, a set of computer simulations is performed in the reverse link in which each user signal undergoes different multipath Rayleigh fading. The results show us a superior performance of our system over other CDMA systems in terms of SNR to BER measurements.

A Case Study on the Practical Use of PDA for Panel Survey (패널조사에서 PDA 활용 사례연구)

  • Lee, Sang-Jun
    • Survey Research
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    • v.6 no.1
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    • pp.63-81
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    • 2005
  • A survey method in Korea has being developed rapidly since a survey company was established in 1968. In latest, the CATI, internet survey, Notebook, PDA survey methods are being utilized in accordance with communication development. This article focuses on the practical use and the strength and weakness of the PDA survey solution which employs 'KISS' system designed by KRIVET itself. The survey using PDA has, on the one hand, such strengths as follows : 1) efficient field control, 2) reduction of time for verifying data and generation of proper data 3) shortening survey duration from intial survey to data completion, 4) cutting down survey personnel and cost. On the other hand, survey using PDA has the following weakness: 1) limitation of questionnaire expression, 2) increasing time for survey, 3) communication barrier in some regions.

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Digitally Divided by Choice and the Diffusion of ICTs (정보통신기술의 확산과 선택에 의한 정보격차)

  • Jung, Byung-Kul
    • Journal of Science and Technology Studies
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    • v.6 no.2 s.12
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    • pp.103-129
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    • 2006
  • In spite of decreased attention to digital divide, it has been pointed out as one of the main obstacles to realization of information society. At the outset, two conflicting explanations, optimism and pessimism, have directed their attention to objective basis of digital divide in common. They, however, have been neglected the fact that accessibilities can be varied not only by objective conditions but by subjective conditions such as individual recognition of necessity and willingness. Subsequent choices can be a crucial factor to determine whether to or not to access. In USA, over 50% of potential users determined not to access to the internet by their own will and choices. By the user survey on internet, 'do not feel the necessity' ranked the first reason not to use the internet in South Korea. The respondents who chose 'no time to use' tend to decrease but kept holding their shares, too. The relative importance of 'not to access' by individual choice have been increased. Whether the non-users of ICTs by choice is in or beyond the scope of digital divide, it evidently shows the necessity and importance of directing our attention to it on the way to information society.

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