• Title/Summary/Keyword: Communication Errors

Search Result 969, Processing Time 0.037 seconds

The Design of Multi-channel Synchronous Communication IC Using FPGA (FPGA를 이용한 다채널 동기 통신용 IC 설계)

  • Yang, Oh;Ock, Seung-Kyu
    • Journal of the Semiconductor & Display Technology
    • /
    • v.10 no.3
    • /
    • pp.1-6
    • /
    • 2011
  • In this paper, the IC(Integrated Circuit) for multi-channel synchronous communication was designed by using FPGA and VHDL language. The existing chips for synchronous communication that has been used commercially are composed for one to two channels. Therefore, when communication system with three channels or more is made, the cost becomes high and it becomes complicated for communication system to be realized and also has very little buffer, load that is placed into Microprocessor increases heavily in case of high speed communication or transmission of high-capacity data. The designed IC was improved the function and performance of communication system and reduced costs by designing 8 synchronous communication channels with only one IC, and it has the size of transmitter/receiver buffer with 1024 bytes respectively and consequently high speed communication became possible. It was designed with a communication signal of a form various encoding. To detect errors of communications, the CRC-ITU-T logic and channel MUX logic was designed with hardware logics so that the malfunction can be prevented and errors can be detected more easily and input/output port regarding each communication channel can be used flexibly and consequently the reliability of system was improved. In order to show the performance of designed IC, the test was conducted successfully in Quartus simulation and experiment and the excellence was compared with the 85C3016VSC of ZILOG company that are used widely as chips for synchronous communication.

A Study on the Corrections in Selected Korean and American Newspapers (한국과 미국 일간신문의 정정보도 기사 비교연구: 조선일보, 한겨레신문, 뉴욕타임스, 샌프란시스코 크로니컬을 중심으로)

  • Im, Yang-June
    • Korean journal of communication and information
    • /
    • v.37
    • /
    • pp.204-236
    • /
    • 2007
  • This study explores the corrections on the Korean and the U. S. daily newspapers for the characteristics and differences through the content analysis. For the research, Chosun Ilbo, Hankyoreh Shinmun, The New York Times and The San Francisco Chronicles are selected. The main differences between the Korean and American newspapers are as follows: Firstly, the average number of newspaper errors in Korean dailies are as half as little of those in the U. S. dailies. Secondly, regarding the subcategory of mistakes, the largest thematical number is the societal matters(36.0%), followed by politics(18.3%) and economy(12.1%) for the Korean newspapers. By contrast, errors in culture(17.4%) is the most frequently made by the American newspaper reporters and editors, followed by lifestyle(8.6%), and sports(7.0%). Thirdly, in terms of content of mistakes, errors in names(26.2%) that occurred the most, followed by misidentifications(18.1%) and misattribution(15.8%) for the Korean dailies; the errors in numbers(33.7%), spelling and typographical errors(12.1%) and date(5.6%) for the U. S. dailies. Fourthly, one of the critical reasons that mistakes occurred because Korean reporters are lack of double checking the stories; the U. S. reporters simply by overlooking the articles. Finally, the Korean newspapers make use of only two kinds of correction formats, while the U.S. newspapers use six different correction formats for their newspaper readers.

  • PDF

Side Information Extrapolation Using Motion-aligned Auto Regressive Model for Compressed Sensing based Wyner-Ziv Codec

  • Li, Ran;Gan, Zongliang;Cui, Ziguan;Wu, Minghu;Zhu, Xiuchang
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.7 no.2
    • /
    • pp.366-385
    • /
    • 2013
  • In this paper, we propose a compressed sensing (CS) based Wyner-Ziv (WZ) codec using motion-aligned auto regressive model (MAAR) based side information (SI) extrapolation to improve the compression performance of low-delay distributed video coding (DVC). In the CS based WZ codec, the WZ frame is divided into small blocks and CS measurements of each block are acquired at the encoder, and a specific CS reconstruction algorithm is proposed to correct errors in the SI using CS measurements at the decoder. In order to generate high quality SI, a MAAR model is introduced to improve the inaccurate motion field in auto regressive (AR) model, and the Tikhonov regularization on MAAR coefficients and overlapped block based interpolation are performed to reduce block effects and errors from over-fitting. Simulation experiments show that our proposed CS based WZ codec associated with MAAR based SI generation achieves better results compared to other SI extrapolation methods.

A Study on Communication Safety and Evaluation Tool in Railway Communication System (열차제어시스템 통신 안정성 및 평가 도구 연구)

  • Kim, Sung-Un;Seo, Sang-Bo;Song, Seung-Mi;Jo, Chan-Hyo;Hwang, Jong-Gyu;Jo, Hyun-Jeong
    • Proceedings of the KSR Conference
    • /
    • 2008.06a
    • /
    • pp.343-352
    • /
    • 2008
  • Safety-critical systems related to the railway communications are currently undergoing changes. Mechanical and electro-mechanical devices are being replaced by programmable electronics that are often controlled remotely via communication networks. Therefore designers and operators now not only have to contend with component failures and user errors, but also with the possibility that malicious entities are seeking to disrupt the services provided by theirs systems. Recognizing the safety-critical nature of the types of communications required in rail control operations, the communications infrastructure will be required to meet a number of safety requirements such as system faults, user errors and the robustness in the presence of malicious attackers who are willing to take determined action to interfere in the correct operation of a system. This paper discusses the safety strategies employed in the railway communications and proposes a security mechanism for Korean railway communication system. We present the developed communication safety evaluation tool based on the proposed security mechanism and also evaluate its protecting capability against the threats of masquerading, eavesdropping, and unauthorized message manipulation.

  • PDF

Development and evaluation of a neonatal intensive care unit medication safety simulation for nursing students in South Korea: a quasi-experimental study

  • Son, Mi Seon;Yim, Minyoung;Ji, Eun Sun
    • Child Health Nursing Research
    • /
    • v.28 no.4
    • /
    • pp.259-268
    • /
    • 2022
  • Purpose: Nursing students are susceptible to medication safety incidents in the neonatal intensive care unit (NICU) related to a lack of communication experience. The purpose of the present study was to investigate the impact of a NICU medication safety simulation (NMSS) focusing on communication clarity, patient hand-off confidence, and patient safety competency in senior-year nursing students. Methods: The study utilized a nonequivalent control group pretest-posttest design. In total, 60 nursing students were assigned to two groups. The experimental group participated in the NMSS, which included three medication error scenarios. Pairs of students completed the scenarios together in 10 to 20 minutes. Data were analyzed using the chi-squared test, independent t test, and ANCOVA. Results: The experimental group showed significant improvements in communication clarity (p=.015), and patient safety competency (p<.001) compared to the control group. Using the pretest values as covariates, patient hand-off confidence scores significantly increased (p=.027). Conclusion: Implementing the NMSS focusing on communication in the pediatric nursing curriculum helped students to communicate clearly and concisely about medication errors, and its use is recommended to promote patient safety competency in the NICU.

Impact of Channel Variations and Channel Estimation Errors on the Error Performance of Convolutional Coded STBC Systems (길쌈 부호화 시공간 블록 부호 시스템의 오류 성능에 대한 채널 변화 및 채널 추정 오류의 영향)

  • Yun, Eunsik;Kim, Sun-Hyung;Park, Sangjoon;Kang, Byeong-Gwon
    • Journal of Digital Convergence
    • /
    • v.16 no.5
    • /
    • pp.231-237
    • /
    • 2018
  • This paper investigates the impact of the channel variations and channel estimation errors on the error performance of convolutional coded STBC systems. We consider the orthogonal Almouti STBC and the quasi-orthogonal Jafarkhani STBC, and the error performance of the convolutional coded STBC system is investigated according to the channel variation and channel estimation error via numerical simulations. Simulation results show that, if the channel variation speed is slow, time diversity effects improve the error performance compared to the static-channel cases. However, if the channel variation speed is fast, unlike ZF or MMSE detection, the conventional STBC detection has the significant performance degradation especially with the quasi-orthogonal Jafarkhani STBC. Further, the error performance of the system is significantly degraded as the channel estimation errors become stronger, regardless of the detection scheme and channel variation speed.

Position and Attitude Estimation of a Capsule Endoscope based on Ultrasonic Ranging (초음파 거리를 이용한 캡슐 내시경의 위치 및 자세각 추정)

  • Kim, Eun-Joung;Kim, Myung-Yu;Kim, Deok-Ki;Kim, Yong-Dae;You, Young-Gap
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.44 no.5
    • /
    • pp.38-44
    • /
    • 2007
  • This paper presented a location and attitude estimation scheme of a capsule endoscope based on ultrasonic ranging. The scheme comprised eight on-capsule ultrasonic sensors to alleviate measurement errors due to irregularities in human body ultrasonic characteristics. It calculated the coordinate values and angles in a Cartesian coordinate system. The Matlab simulation reflecting random errors yielded the average deviations of 0.8mm in the location and $0.2^{\circ}$ in the attitude angle. These values are far smaller than normal intestine movement ranges inside human body, and will contribute accurate diagnosis of intestine.

A Study of TCP Performance with Snoop Protocol over Fading Wireless Links

  • Cho, Yang-Bum;Cho, Sung-Joon
    • Journal of information and communication convergence engineering
    • /
    • v.2 no.4
    • /
    • pp.214-218
    • /
    • 2004
  • In this paper, we have analyzed TCP performance over wireless correlated fading links with and without Snoop protocol. For a given value of the packet error rate, TCP performance without Snoop protocol is degraded as the fading is getting fast (i.e. the user moves fast). When Snoop protocol is introduced in the base station, TCP performance is enhanced in most wireless environments. Especially the performance enhancement derived from using Snoop protocol is large in fast fading channel. This is because packet errors become random and sporadic in fast fading channel and these random packet errors (mostly single packet errors) can be compensated efficiently by Snoop protocol's local packet retransmissions. But Snoop protocol can't give a large performance improvement in slow fading environments where long bursts of packet errors occur. Concerning to packet error rate, Snoop protocol results in the highest performance enhancement in the channel with mid-high values of packet error rate. This means Snoop protocol cannot fully fulfill its ability under too low or too high packet error rate environments.

An Improved Decoding Scheme of LCPC Codes (LCPC 부호의 개선된 복호 방식)

  • Cheong, Ho-Young
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.11 no.4
    • /
    • pp.430-435
    • /
    • 2018
  • In this paper, an improved decoding scheme for low-complexity parity-check(LCPC) code with small code length is proposed. The LCPC code is less complex than the turbo code or low density parity check(LDPC) code and requires less memory, making it suitable for communication between internet-of-things(IoT) devices. The IoT devices are required to have low complexity due to limited energy and have a low end-to-end delay time. In addition, since the packet length to be transmitted is small and the signal processing capability of the IoT terminal is small, the LCPC coding system should be as simple as possible. The LCPC code can correct all single errors and correct some of the two errors. In this paper, the proposed decoding scheme improves the bit error rate(BER) performance without increasing the complexity by correcting both errors using the soft value of the modulator output stage. As a result of the simulation using the proposed decoding scheme, the code gain of about 1.1 [dB] was obtained at the bit error rate of $10^{-5}$ compared with the existing decoding method.

Research Activities and Techniques for the Prevention of Human Errors during the Operation of Nuclear Power Plants (가동 중 원자력발전소의 인적 오류 예방 기술 개발)

  • Lee, Yong-Hee;Jang, Tong-Il;Lee, Yong-Hee;Oh, Yeon-Ju;Kang, Seok-Ho;Yun, Jong-Hun
    • Journal of the Ergonomics Society of Korea
    • /
    • v.30 no.1
    • /
    • pp.75-86
    • /
    • 2011
  • This paper describes several current research activities and the field techniques for the prevention of human errors during the operation of nuclear power plants(NPPs). The human aspects such as 'fitness for the duties', 'job competence and suitability', 'types of communication', 'behaviors of field workers', 'teamwork of main control room crews', 'task procedures', etc. have been investigated for improving the performance of operating personnel in NPPs. We decide to develop a set of the complementary techniques for the reduction of human errors. The set of techniques developed includes teamwork criteria, jobs fitness analysis, procedure enhancement guide, 3-way communication, campaign posters, a behavior based safety program, a procedure guideline, and a task hazard identification method for the field practitioners in NPPs. These can offer a set of significant human error countermeasures to be considered for analyzing and reducing human error in NPPs as well as other fields of industry.