• Title/Summary/Keyword: Line coding

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A Study on Forward Error Correction of Long-Distance Submarine Optical Communication Systems (장거리 해저 광통신시스템의 순방향에러정정 기술 연구)

  • Jung, Jae-Jin;Lee, Young-Sun;Shin, Hyun-Sik
    • The Journal of the Korea institute of electronic communication sciences
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    • v.3 no.3
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    • pp.170-176
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    • 2008
  • According to the development of Internet, DWDM system needs to improve the performance for long distance transmission international optical signals. For higher the transmission capacity, we have to raise the transmission speed and increase a number of channels. To make qualifications, there are a lot of technologies such as line coding, modulation, precious fiber, broadband amplification, dispersion and forward error correction. Especially, FEC has been considered as a progressive technology for long distance transmission to carry out high speed and large capacity traffic. This paper introduced the progress of each new generation of FEC and the way to employ by current system analyzed the coding gain.

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Turbo Coded OFDM Scheme for a High-Speed Power Line Communication (고속 전력선 통신을 위한 터보 부호화된 OFDM)

  • Kim, Jin-Young;Koo, Sung-Wan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.1
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    • pp.141-150
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    • 2010
  • In this paper, performance of a turbo-coded OFDM system is analyzed and simulated in a power line communication channel. Since the power line communication system typically operates in a hostile environment, turbo code has been employed to enhance reliability of transmitted data. The performance is evaluated in terms of bit error probability. As turbo decoding algorithms, MAP (maximum a posteriori), Max-Log-MAP, and SOVA (soft decision viterbi output) algorithms are chosen and their performances are compared. From simulation results, it is demonstrated that Max-Log-MAP algorithm is promising in terms of performance and complexity. It is shown that performance is improved 3dB by increasing the number of iterations, 2 to 8, and interleaver length of a turbo encoder, 100 to 5000. The results in this paper can be applied to OFDM-based high-speed power line communication systems.

Strategies on Text Screen Design Of The Electronic Textbook For Focused Attention Using Automatic Text Scroll (자동 스크롤 가능을 이용한 주의력 집중을 위한 웹기반 전자교과서 텍스트 화면 설계전략)

  • Kwon, Hyunggyu
    • The Journal of Korean Association of Computer Education
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    • v.5 no.4
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    • pp.134-145
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    • 2002
  • The purpose of this study is to present the functional and technical solutions for text learning of web-based textbook in which each letter has its own focal point. The solutions help learners not to lose the main focus when eye moves to the next letter or line. The text screen of the electronic textbook automatically scrolls the text to up and down or left and right directions which are preassigned by learner. It doesn't need the operation of mouse or keyboard. And learner can change scroll speed and types anytime during scrolling. Automatic text scroll function is a solution for controlling data and screen to reflect the personal favor and ability. It contains the content structure of the text(characteristics, categorizations etc.), the appearance of the text(density, size, font etc.), scroll options(scroll, speed etc.), program control type(ram resident program etc.), and the application of the screen design principles(legibility etc.). To resolve these functional problems, technical 8 phases are provided, which are environment setting, scroll option setting, copy, data analysis, scroll coding, centered focus coding, left and right focus coding, implementation. The learner can focus on text without dispersion because the text focal points stay in the fixed area of screen. 1bey read the text following their preferences for fonts, sizes, line spacing and so on.

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Down-regulation of Long Non-coding RNA TUG1 Inhibits Osteosarcoma Cell Proliferation and Promotes Apoptosis

  • Zhang, Qiang;Geng, Pei-Liang;Yin, Pei;Wang, Xiao-Lin;Jia, Jin-Peng;Yao, Jie
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.4
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    • pp.2311-2315
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    • 2013
  • Objective: To investigate the expression level of TUG1 and one of its transcript variants (n377360) in osteosarcoma cells and assess the role of TUG1 in proliferation and apoptosis in the U2OS cell line. Methods: TUG1 and n377360 expression levels in patients with osteosarcomas and the U2OS human osteosarcoma cell line were evaluated using real-time quantitative PCR. U2OS cells were transected with TUG1 and n377360 siRNA or non-targeting siRNA. MTS was performed to assess the cell proliferation and flow cytometry was applied to analyze apoptosis. Results: We found significantly higher TUG1 and n377360 expression levels in osteosarcoma tissues compared with matched non-tumorous tissues. In line with this, suppression of TUG1 and n377360 expression by siRNA significantly impaired the cell proliferation potential of osteosarcoma cells. Furthermore, inhibition of TUG1 expression significantly promoted osteosarcoma cell apoptosis. Conclusions: The overexpression of TUG1 and n377360 in osteosarcoma specimens and the functional role of TUG1 and n377360 regarding cell proliferation and apoptosis in an osteosarcoma cell line provided evidence that the use of TUG1 or n377360 may be a viable but an as yet unexplored therapeutic strategy in tumors that over express these factors.

Development of a Simulator for Off-Line Programming of Gantry-Robot Welding System

  • Ahn, Cheol-Ki;Lee, Min-Cheol;Kwon Son;Park, Jae-Won;Jung, Chang-Wook;Kim, Hyung-Sik
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.517-517
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    • 2000
  • Welding automation is one of the most important manufacturing issues in shipbuilding in order to lower the cost, increase the quality, and avoid the labor problems. Generally the on-line teaching is utilized on the robot that is used in the welding automation system, but it requires much effort and long time to program. Especially, if the system is composed of more than two cooperating robots, it demands much more skill to program the robots' motion. Thus, a convenient programming tool is required for efficient utilization of welding automation system. In this study, a convenient programming tool is developed for welding automation in which gantry-robot system is used. The system is composed of a gantry transporter and two robots mounted on the gantry to cover the wide work range in the ship building application. As a programming tool, an off-line programming software based on PC is developed. By using this software, field operator does not need to concern about coding of task programs for three control units, one is for gantry and two are for robots. The task programs are automatically generated by assembling the program modules in database according to geometrical information of workpiece and welding condition, which become the only concern of field operator, The feasibility of the generated programs can be verified via a motion simulator previously to on-line running.

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miR-153 Silencing Induces Apoptosis in the MDA-MB-231 Breast Cancer Cell Line

  • Anaya-Ruiz, Maricruz;Cebada, Jorge;Delgado-Lopez, Guadalupe;Sanchez-Vazquez, Maria Luisa;Perez-Santos, Jose Luis Martin
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.2983-2986
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    • 2013
  • MicroRNAs (miRNAs) are small, non-coding RNAs (18-25 nucleotides) that post-transcriptionally modulate gene expression by negatively regulating the stability or translational efficiency of their target mRNAs. In this context, the present study aimed to evaluate the in vitro effects of miR-153 inhibition in the breast carcinoma cell line MDA-MB-231. Forty-eight hours after MDA-MB-231 cells were transfected with the miR-153 inhibitor, an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was utilized to determine the effects of miR-153 on cell viability. Flow cytometry analysis and assessment of caspase 3/7 activity were adopted to determine whether miR-153 affects the proliferation rates and apoptosis levels of MDA-MB-231 cells. Our results showed that silencing of miR-153 significantly inhibited growth when compared to controls at 48 hours, reducing proliferation by 37.6%, and inducing apoptosis. Further studies are necessary to corroborate our findings and examine the potential use of this microRNA in future diagnostic and therapeutic interventions.

Customized Nursing Care Types and Process;Focusing on Home Care Services (맞춤간호유형 및 과정;가정간호서비스를 중심으로)

  • Kang, So-Young
    • Journal of Korean Academy of Nursing Administration
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    • v.14 no.1
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    • pp.13-25
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    • 2008
  • Purpose: The study aimed at providing better understanding of the way of carrying out nursing practice tailored to meet patient's individuality, and types of customized care in home care settings. Method: This study was conducted with qualitative design, using a grounded theory method. The directors of the home care department at three general hospitals nominated 12 staff nurses who had the experience of customized care. The data were collected using interview and field observation, and analyzed line-by-line with steps of coding. Result: The core category of customized care was 'caring in a precise manner suited to patient's individuality'. The central phenomenon was 'desire to do more for patient'. The action and interactions were: (a) knowing a patient all the more, (b) making a special relationship to a patient, (c) designing care alternatives reflecting individuality, and (d) performing the care alternatives reflecting individuality. Three types of customized care were the following: (a) completion of customized care, (b) an attempt to customized care, and (c) abandonment of working for customized care. Conclusions: The knowledge of customized care would be based on development of nursing practice program focusing on patient' individuality, and instrument development necessary for further research on care customization.

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A Fundamental Study for Establishment of Channel Data Base in Power-Line Communications (전력선 통신 채널 Data Base 구축을 위한 기본 연구)

  • Oh, Hui-Myoung;Kim, Kwan-Ho;Lee, Won-Tae;Lee, Jae-Jo
    • Proceedings of the KIEE Conference
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    • 2002.07d
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    • pp.2619-2621
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    • 2002
  • 전력선 통신(Power-Line Communication)은 기본적으로 데이터 전송용이 아닌 전력 전달을 목적으로 설계된 전력선을 매체로 이루어지기 때문에 상당한 잡음과 감쇠 특성을 보이며 또 전력선 topology와 부하의 변화에 따라 전달 함수(transfer function)의 변화도 심하다. 이러한 열악한 채널 특성을 극복하기 위해 전력선 채널에 관한 많은 연구가 진행되고 있으며 그 중에서도 채널 모델링 연구가 활발하게 진행되고 있다. 채널 모델링은, 변복조 방식, 채널 코딩(coding), 커플링(coupling), 필터링(filtering) 등의 적극적인 채널 극복 방안으로서 제시되는 기술을 적용함에 있어서 상당히 중요하다. 본 논문에서는, 채널 모델링 기법으로 제시되고 있는 방식인, 전달 함수 특성과 여러 가지 잡음 특성을 결합한 통계적 모델링 방식[l]을 통해 전력선 채널 모델을 구현하여 실측치와 비교 검토하고, 또 모델링을 통해 얻어지는 파라미터(parameter)를 통해 채널 정보를 효과적으로 Data Base화 할 수 있는 방안에 대해 연구하였으며, 이 Data Base의 활용 방안을 모색하였다.

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Enhanced Spatial Modulation of Indoor Visible Light Communication

  • Shan, Ye;Li, Ming;Jin, Minglu
    • Journal of information and communication convergence engineering
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    • v.13 no.1
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    • pp.1-6
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    • 2015
  • In this study, we consider visible light communication in an indoor line-of-sight environment. It has been proved that among the multiple input multiple output (MIMO) techniques, spatial modulation (SM) performs better than repetition coding (RC) and spatial multiplexing (SMP). On the basis of a combination of SM and pulse amplitude modulation (PAM), here, we propose an enhanced SM algorithm to improve the bit error rate. Traditional SM activates only one light-emitting diode (LED) at one time, and the proposed enhanced SM activates two LEDs at one time and reduces the intensity levels of PAM by half. Under the condition of a highly correlated channel, power imbalance is used to improve the algorithm performance. The comparison between the two schemes is implemented at the same signal-to-noise ratio. The simulation results illustrate that the enhanced SM outperforms the traditional SM in both highly correlated and lowly correlated channels. Furthermore, the proposed enhanced SM scheme can increase the transmission rate in most cases.

Analysis of the chloroplast genome and SNP detection in a salt tolerant breeding line in Korean ginseng

  • Jo, Ick-Hyun;Bang, Kyong-Hwan;Hong, Chi Eun;Kim, Jang-Uk;Lee, Jung-Woo;Kim, Dong-Hwi;Hyun, Dong-Yun;Ryu, Hojin;Kim, Young-Chang
    • Journal of Plant Biotechnology
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    • v.43 no.4
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    • pp.417-421
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    • 2016
  • The complete chloroplast genome sequence of Panax ginseng breeding line 'G07006', showing higher salt tolerance, was confirmed by de novo assembly using whole genome next-generation sequences. The complete chloroplast (CP) genome size is 156,356 bp, including two inverted repeats (IRs) of 52,060 bp, separated by the large single-copy (LSC 86,174 bp) and the small single-copy (SSC 18,122 bp) regions. One hundred fourteen genes were annotated, including 80 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Among them, 18 sites were duplicated in the inverted repeat regions. By comparative analyses of the previously identified CP genome sequences of nine cultivars of P. ginseng and that of G07006, five useful SNPs were defined in this study. Since three of the five SNPs were cultivar-specific to Chunpoong and Sunhyang, they could be easily used for distinguishing from other ginseng accessions. However, on arranging SNPs according to their gene location, the G07006 genotype was 'GTGGA', which was distinct from other accessions. This complete chloroplast DNA sequence could be conducive to discrimination of the line G07006 (salt-tolerant) and further enhancement of the genetic improvement program for this important medicinal plant.