• Title/Summary/Keyword: REED

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Performance Analysis of Multimedia CDMA Network with Concatenated Coding and RAKE Receiver

  • Roh Jae-Sung;Kim Choon-Gil;Cho Sung-Joon
    • Journal of information and communication convergence engineering
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    • v.2 no.3
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    • pp.139-144
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    • 2004
  • In order to transmit various types of multimedia data (i.e. voice, video, and data) over a wireless channel, the coding and modulation scheme needs to be flexible and capable of providing a variable quality of service, data rates, and latency. In this paper, we study a mobile multimedia COMA network combined with the concatenated Reed-Solomon/Rate Compatible Punctured Convolution code (RS/RCPC). Also, this paper propose the combination of concatenated RS/RCPC coder and COMA RAKE receiver for multimedia COMA traffic which can be sent over wireless channels. From the results, using a frequency selective Rayleigh fading channel model, it is shown that concatenated RS/RCPC coder at the wireless physical layer can be effective in providing reliable wireless multimedia CDMA network. And the proposed scheme that combine concatenated RS/RCPC coder and CDMA RAKE receiver provides a significant gain in the BER performance over multi-user interference and multipath frequency selective fading channels.

A Method of Effective Error Correction for Burst Error in OFDM using RS signal (RS 부호를 이용한 OFDM에서 연집 오류에 효과적인 오류정정 기법)

  • Kim, Tae-Hoon
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.507-510
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    • 2010
  • OFDM(Orthogonal Frequency Division Multiplexing)은 하나의 데이터 열(data stream)을 낮은 데이터 전송률을 갖는 작은 데이터로 나누고, 이들을 부반송파(subcarrier)를 통해 동시에 전송한다. OFDM이 차세대 전송방식으로 채택된 이유는 주파수 선택적 페이딩(frequency selective fading)이나 협대역(narrow band)간 간섭에 받는 영향이 적어 고속 통신이 가능하기 때문이다. 본 논문에서는 RS 부호(Reed-Solomon Code)를 사용하여 OFDM에서 대용량 데이터를 전송할 때 발생하기 쉬운 연집 오류(burst error)를 정정하도록 하였다. 또한 채널 사이에 파일롯 심볼(pilot symbol)을 삽입하여 채널 추정을 통한 신호의 타이밍 오류도 고려하였다.

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A Performance Analysis of FEC Coding Method in Rayleigh Satellite Return Link Channel (레일리 위성 리턴링크 채널에서 FEC 부호 방식 성능분석)

  • Lee Seong Ro;Cho Sung Eui;Oh Deock gil
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.12C
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    • pp.1633-1641
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    • 2004
  • In satellite digital broadcasting and satellite internet, severe burst errors occur in the high-speed return channel from the satellite to mobiles. In this paper, we analyze the performance of the forward error correction (FEC) coding method in the Rayleigh fading return channel. We first investigate the channel model of Loo, LutB, Vucetic and Corazza. We then compare the performance of the convolutional, Reed-Solomon (RS), convolution-RS concatenation, and Turbo codes in rayleigh fading channel.

Epstein-Barr Virus-Associated Classical Hodgkin Lymphoma and Its Therapeutic Strategies

  • Lee, Im-Soon
    • Biomolecules & Therapeutics
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    • v.19 no.4
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    • pp.398-410
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    • 2011
  • Over the past few decades, our understanding of the epidemiology and immunopathogenesis of Hodgkin lymphoma (HL) has made enormous advances. Consequently, the treatment of HL has changed significantly, rendering this disease of the most curable human cancers. To date, about 80% of patients achieve long-term disease-free survival. However, therapeutic challenges still remain, particularly regarding the salvage strategies for relapsed and refractory disease, which need further identification of better prognostic markers and novel therapeutic schemes. Although the precise molecular mechanism by which Epstein-Barr virus (EBV) contributes to the generation of malignant cells present in HL still remains unknown, current increasing data on the role of EBV in the pathobiology of HL have encouraged people to start developing novel and specific therapeutic strategies for EBV-associated HL. This review will provide an overview of therapeutic approaches for acute EBV infection and the classical form of HL (cHL), especially focusing on EBV-associated HL cases.

A Method of Effective Error Correction for Burst Error in OFDM (OFDM에서 연집 오류에 효과적인 오류정정 기법)

  • Jung, Young-Hoon;Lee, Kwang-Hyung;Jun, Moon-Seog
    • Proceedings of the KAIS Fall Conference
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    • 2007.11a
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    • pp.248-251
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    • 2007
  • OFDM(Orthogonal Frequency Division Multiplexing)은 하나의 데이터 열(data stream)을 낮은 데이터 전송률을 갖는 작은 데이터로 나누고, 이들을 부반송파(subcarrier)를 통해 동시에 전송한다. OFDM이 차세대 전송방식으로 채택된 이유는 주파수 선택적 페이딩(frequency selective fading)이나 협대역(narrow band)간 간섭에 받는 영향이 적어 고속 통신이 가능하기 때문이다. 본 논문에서는 RS 부호(Reed-Solomon Code)를 사용하여 OFDM에서 대용량 데이터를 전송할 때 발생하기 쉬운 연집 오류(burst error)를 정정하도록 하였다. 또한 채널 사이에 파일롯 심볼(pilot symbol)을 삽입하여 채널 추정을 통한 신호의 타이밍 오류도 고려하였다.

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Design of a RS(23,17) Reed-Solomon Decoder (RS(23,17) 리드-솔로몬 복호기 설계)

  • Kang, Sung-Jin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.12
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    • pp.2286-2292
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    • 2008
  • In this paper, we design a RS(23,17) decoder for MB-OFDM(Multiband-Orthogonal Frequency Division Multiplexing) system, in which Modified Euclidean(ME) algorithm is adopted for key equation solver block. The proposed decoder has been optimized for MB-OFDM system so that it has less latency and hardware complexity. Additionally, we have implemented the proposed decoder using Verilog HDL and synthesized with Samsung 65nm library. From synthesis results, it can operate at clock frequency of 250MHz, and gate count is 20,710.

Gastric Ulceration and Bleeding with Hemodynamic Instability Caused by an Intragastric Balloon for Weight Loss

  • Reed, Larrite;Edriss, Hawa;Nugent, Kenneth
    • Clinical Endoscopy
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    • v.51 no.6
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    • pp.584-586
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    • 2018
  • Obesity in the United States is a medical crisis with many people attempting to lose weight with caloric restriction. Some patients choose minimally invasive weight loss solutions, such as intragastric balloon systems. These balloon systems were approved by the Federal Drug Administration (FDA) in 2015-2016 and have been considered safe, with minimal side effects. We report a patient with a two-day history of melena, abdominal pain, hypotension, and syncope which developed five months after placement of an intragastric balloon. Esophagogastroduodenoscopy with balloon removal revealed a small 8-mm gastric ulcer in the incisura. This gastric ulcer probably developed secondary to mechanical compression of the stomach mucosa by the gastric balloon which contained 900 mL of saline. The FDA is now investigating five deaths since 2016 associated with these second-generation balloons. Clinicians should be aware of these complications when evaluating patients with gastrointestinal complications, such as bleeding.

Error resilience video coding of DMB video stream using AVC redundant slice (AVC 잉여슬라이스를 이용한 DMB 비디오 스트림의 오류내성부호화)

  • Hong, Sung-Hoon;Baek, Sun-Hye;Na, Nam-Woong
    • Proceedings of the Korea Information Processing Society Conference
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    • 2004.05a
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    • pp.707-710
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    • 2004
  • In the case of terrestrial DMB(Digital Multimedia Broadcasting) system that offers mobile multimedia broadcasting services, transmission error must be considered. Although DMB transmission system provides the error protection functions of convolution coding and Reed-Solomon (204,188,t=8) coding, additional error resilience video coding methods are needed to satisfy the requirement of BER lower than $10^{-8}$. In this thesis, we propose and evaluate effective error resilience coding schemes using the MPEG-4 redundant slice for MPEG-4 video services in the DMB environment. In this scheme, we analyze the drift error caused by transmission error based on the random noise concept and the redundant slice selection algorithm that selects the most influential slice in the view of the drift error increment.

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Design and Performance Analysis of Visible -Light Wireless Communication System using LED

  • Choi, Jae Myoeng
    • Journal of Advanced Information Technology and Convergence
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    • v.8 no.2
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    • pp.147-157
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    • 2018
  • In this study, we analyzed an outdoor visible light communication system and implemented it through a simulation. We designed a Reed-Solomon encoder, a variable interleaver structure, and set it to the Institute of Electrical and Electronics Engineers (IEEE) 802.15.7 PHY I specification mode. We also analyzed the performance of an additive white gaussian noise (AWGN) channel environment using a root-raised-cosine (RRC) filter, implemented a MATLAB simulation and analyzed its performance. The results showed a requirement for an additional signal-to-noise ratio (SNR) of approximately 1.5 dB in a 3-ray multipath visible light channel environment than in an AWGN environment.

A Study on the Leakage Current Detection System of Lighting Installation Using IoT Technology (IoT를 기반한 조명설비 누전사고 감지시스템에 관한 연구)

  • Park, Kun-Young;Kwak, Dong-Kurl;Lee, Bong-Seob;Kim, Choon-Sam;Jeon, Ho-Jin
    • Proceedings of the KIPE Conference
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    • 2018.11a
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    • pp.7-8
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    • 2018
  • In this study, we develop a leakage current detection device of lighting installation. The reed switch using in proposed device is activated when the leakage current is generated. We also design a GUI system of a management computer using LabVIEW and administrator's mobile phone app based on IoT. As results, this study is to build an IoT convergence system and it aims to protect people and property by coping with leakage current fault in real time.

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