• Title/Summary/Keyword: Channel selection

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Influence of Personality Types on Ttelevision Contents Preference (개인성향과 텔레비전 프로그램 유형 선호도의 관계 연구)

  • Yang, Moon-Hee
    • The Journal of the Korea Contents Association
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    • v.11 no.12
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    • pp.230-240
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    • 2011
  • The personality types has been emphasized as one of the influential factors for the program selection by viewers in the multi-channel and multimedia era. However, there have been few empirical studies on this issue. The current study investigated how the audience personality influence the program preference. Specifically, this study focused on both need for cognition and sensation seeking which are related to the television viewing motivation. To examine the influence of personality on program preference, four types of drama and five types of entertainment programs were used. The results of the web survey showed that viewers personality type seem to have effect on their program preference. Indeed, it appeared that there was positive relationship between need for cognition and sensation seeking. The implications of this study's findings were discussed.

An Energy Efficient and Fair MAC Protocol Using Preamble Counting for Wireless Sensor Networks (무선 센서 네트워크의 MAC 프로토콜에서 에너지 효율성과 공정성 향상을 위한 기법 연구)

  • Lee, Dong-Ho;Chung, Kwang-Sue
    • Journal of KIISE:Information Networking
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    • v.35 no.2
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    • pp.149-157
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    • 2008
  • Since wireless sensor networks consist of nodes with the constrained battery, energy efficient MAC operation is one of the important issues. Low duty cycle operation is critical to conserve energy in wireless sensor network MAC protocol. Some paper proposed a new approach to low power listening, which employs a short preamble to further reduce energy consumption and to reduce latency. But short preamble suffers from unfair channel access problem since there was no consideration for contention between transmission nodes. Preamble counting proposes a solution to each of these problems by employing node selection information. Simulation results show that the preamble counting provides an improved energy efficiency and fairness of packet delivery.

Quantitative Evaluation of Scratch Related Tool Life for Stamping of UHSS Using Pin-on-Flat Surface Test (Pin-on-Flat Surface Test를 이용한 초고장력강판 스탬핑 금형의 정량적 스크래치 수명평가)

  • Choi, H.S.;Kim, S.G.;Kim, B.M.;Ko, D.C.
    • Transactions of Materials Processing
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    • v.22 no.2
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    • pp.86-92
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    • 2013
  • When stamping ultra-high-strength steel (UHSS), the phenomenon of galling, which corresponds to a transfer of material from the sheet to the tool surface, occurs because of the high contact pressure between tool and workpiece. Galling leads to increased friction, unstable interface conditions, scratches on the sheet and the tool surfaces and, eventually, premature tool surface failures. Therefore, a simple and accurate evaluation method for tool scratching is necessary for the selection of tool material and coating, as well as for a better optimization of process conditions such as blank holder force and die radius. In this study, the pin-on-disc (PODT) and pin-on-flat surface (POFST) tests are conducted to quantitatively evaluate scratch-related tool life for stamping of UHSS. The variation of the friction coefficient is used as an indicator of scratch resulted from galling. The U-channel ironing test (UCIT) is performed in order to validate the results of the friction tests. This study shows that the POFST test provides a good quantitative estimation of tool life based on the occurrence of scratch.

Hubble Space Telescope's Near-IR and Optical Photometry of Globular Cluster Systems in the Fornax and Virgo Clusters of Galaxies

  • Cho, Hyejeon;Blakeslee, John P.;Lee, Young-Wook
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.69.2-69.2
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    • 2014
  • We present space-based near-IR (NIR) and optical photometry of globular clusters (GCs) of 16 early-type galaxies in the Fornax and Virgo Clusters. The NIR imaging data for the nearby galaxies was acquired with the IR Channel of the Wide Field Camera 3 (WFC3/IR) in the F110W ($J_{110}$) and F160W ($H_{160}$) bandpasses. We introduce the full sample of our WFC3/IR program, describe data reductions and photometric measurements including GC candidate selection criteria, and then show selected GCs' color-magnitude diagrams. The tilted features in the diagrams related to the morphological types of host galaxies are discussed in the context of galaxy formation and evolution histories. Combining F475W ($g_{475}$) and F850LP ($z_{850}$) data taken from the Advanced Camera for Surveys Virgo and Fornax Cluster Surveys with our NIR data, we investigate the bimodality in optical-NIR color distribution and the nonlinear feature of the optical-NIR color relation as a function of optical color for these extragalactic GC systems.

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Opportunistic Transmit Cognitive Radio Relay Systems with CSI Delay (CSI 지연을 갖는 기회전송 상황 인지 릴레이 시스템)

  • Kim, Nam-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.5
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    • pp.39-44
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    • 2010
  • In this paper, we analyze the performance of the cooperative cognitive radio relay system which is adapted the recently highly focused cognitive radio system. The performance comparison is made between the system with and that without the opportunistic transmission relay. Especially the selection combining is considered at the destination for simple implementation. In this case, the effect of the channel state information (CSI) delay, which is caused essentially by the process during the CSI delivery, to the system performance is considered. It is noticed that the performance of the system with the opportunistic relay degrades up to 0.6 dB at a given condition compared to the system without the opportunistic relay. And it is shown that the system performance is more sensitive to the CSI delay compared to the frequency acquisition probability of the cognitive radio relay.

Perfonnance Analysis of the Combined AMC-MIMO Systems with MCS Level Selection Method (MCS 레벨 선택 방식에 따른 AMC-MIMO 결합 시스템의 성능 비교)

  • Hwang In-Tae;Kang Min-Goo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.7C
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    • pp.665-671
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    • 2006
  • In this paper, we propose and observe a system that adopts Independent-MCS (Modulation and Coding Scheme) level for each layer in the combined AMC-V-BLAST (Adaptive Modulation and Coding-Vertical-Bell-lab Layered Space-Time) system. Also, comparing with the combined system using Common-MCS level, we observe throughput performance improvement. As a result of simulation, Independent-MCS level case adapts modulation and coding scheme for maximum throughput to each channel condition in separate layer, resulting in improved throughput compared to Common-MCS level case. Especially, the results show that the combined AMC-V-BLAST system with Independent-MCS level achieves a gain of 700kbps in $7dB{\sim}9dB$ SNR (Signal-to-Noise Ratio) range.

The Performance of DS/SSMA BPSK Communication with Microscopic and Macroscopic Diversity in Mobile Radio Channel (이동 무선채널에서 마이크로소코픽과 매크로스코픽 다이버시티를 사용한 DS/SSMA BPSK 통신 의 성능 분석)

  • 강병권;김기전;황금찬
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.1
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    • pp.100-109
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    • 1993
  • In this paper, the performance of DS /SSMA BPSK communication system with maximal ratio combining microscopic diversity and selection macroscopic diversity is analyzed. The effects of Rayleigh fading and log normal shadowing on system performance are analyzed, and the validity of microscopic and macroscopic diversity to mitigate the two fading effects are estimated. The increase of the number of chips is effective for mitigating log norma; shadowing, while the increase of the order of microscopic diversity is not. And the higher the standard deviation of shadowing, the more effective the macroscopic diversity.

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Multiple Description Coding using Whitening Ttansform

  • Park, Kwang-Pyo;Lee, Keun-Young
    • Proceedings of the IEEK Conference
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    • 2002.07b
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    • pp.1003-1006
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    • 2002
  • In the communications systems with diversity, we are commonly faced on needing of new source coding technique, error resilient coding. The error resilient coding addresses the coding algorithm that has the robustness to unreliability of communications channel. In recent years, many error resilient coding techniques were proposed such as data partitioning, resynchronization, error detection, concealment, reference picture selection and multiple description coding (MDC). Especially, the MDC using correlating transform explicitly adds correlation between two descriptions to enable the estimation of one set from the other. However, in the conventional correlating transform method, there is a critical problem that decoder must know statistics of original image. In this paper, we propose an enhanced method, the MDC using whitening transform that is not necessary additional statistical information to decode image because the DCT coefficients to apply whitening transform to an image have uni-variance statistics. Our experimental results show that the proposed method achieves a good trade-off between the coding efficiency and the reconstruction quality. In the proposed method, the PSNR of images reconstructed from two descriptions is about 0.7dB higher than conventional method at the 1.0 BPP and from only one description is about 1,8dB higher at the same rate.

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A Study on the Enhancement of Medical Information Service Functions by the Utilization of CD-ROM (CD-ROM을 활용한 의학정보봉사기능의 제고방안에 관한 연구)

  • Yun Hee-Yun
    • Journal of the Korean Society for Library and Information Science
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    • v.27
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    • pp.183-214
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    • 1994
  • The purpose of this study is to suggest the schemes to enhance information service functions by the utilization of CD-ROM in medical school libraries. The results of the study are summarized as follows : 1. The selection and evaluation of CD-ROM database are necessary steps in the planning of a CD-ROM. Before the CD-ROM is selected, therefore, medical libraries must make a practical evaluation criteria in important order of information services environment, characteristics of hardware/software, service requirements, price and cost, etc. 2. If possible, CD-ROM MEDLINE must be suited for the information services environment. 3. In case of the popular core journals, full-text CD-ROM should be gradually purchased. 4. In order to reduce the time required from search of bibliographic informations to receipt of original articles, CD-NET system and library holding administration program must be built up and developed. And channel of information search and order/receipt of original article should be varied. 5. Search education program for medical librarians and users should be enforced, and librarians must play an important role in CD-ROM retrieval consultant and intermediator.

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CONSIDERATIONS IN THE DEVELOPMENT OF FUTURE PIG BREEDING PROGRAM - REVIEW -

  • Haley, C.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.4 no.4
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    • pp.305-328
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    • 1991
  • Pig breeding programs have been very successful in the improvement of animals by the simple expedient of focusing on a few traits of economic importance, particularly growth efficiency and leanness. Further reductions in leanness may become more difficult to achieve, due to reduced genetic variation, and less desirable, due to adverse correlated effects on meat and eating quality. Best linear unbiased prediction (BLUP) of breeding values makes possible the incorporation of data from many sources and increases the value of including traits such as sow performance in the breeding objective. Advances in technology, such as electronic animal identification, electronic feeders, improved ultrasonic scanners and automated data capture at slaughter houses, increase the number of sources of information that can be included in breeding value predictions. Breeding program structures will evolve to reflect these changes and a common structure is likely to be several or many breeding farms genetically linked by A.i., with data collected on a number of traits from many sources and integrated into a single breeding value prediction using BLUP. Future developments will include the production of a porcine gene map which may make it possible to identify genes controlling economically valuable traits, such as those for litter size in the Meishan, and introgress them into nucleus populations. Genes identified from the gene map or from other sources will provide insight into the genetic basis of performance and may provide the raw material from which transgenic programs will channel additional genetic variance into nucleus populations undergoing selection.