• 제목/요약/키워드: Frequency Resource

검색결과 864건 처리시간 0.032초

다중안테나 OFDM 멀티캐스트 시스템을 위한 동적 자원할당 알고리즘 (Dynamic Resource Allocation Scheme for Multiple Antenna OFDM-based Wireless Multicast Systems)

  • 슈지안;이상진;강우석;서종수
    • 방송공학회논문지
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    • 제13권6호
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    • pp.883-891
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    • 2008
  • 최근 차세대 무선 통신 시스템으로 다중 안테나 직교 주파수 다중접속 방식(OFDM)에서 적응적 자원 할당 기술은 사용자들의 QoS를 보장하며 성능을 개선 할 수 있는 중요한 연구 분야로 각광을 받고 있다. 그러나, 현재까지, 대부분의 자원 할당 알고리즘은 유니캐스트 시스템에 국한되어 연구가 진행되고 있다. 따라서, 본 논문에서는 다중 안테나 직교 주파수 다중접속 방식 시스템에서 멀티캐스트 서비스를 위한 동적 자원 할당 기술을 제안하고 이에 대한 전산모의 실험 결과를 통하여 성능 개선 효과를 분석하였다. 실험 분석 결과, 제안하는 동적 자원 할당 기술이 기존의 방식에 비해 우월함을 증명하였다.

가축 사양 관리 자동화를 위한 전자 개체 인식 장치 개발 (Development of an Electronic Identification Unit for Automatic Dairy Farm Management)

  • 조성인;류관희;안광재;김유용;유윤관
    • 한국축산시설환경학회지
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    • 제8권2호
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    • pp.63-72
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    • 2002
  • In Korea, a need of automatic dairy farm management system has been increased to lower production cost and to strengthen international competition. However, the present management system was mostly relied on foreign technologies and caused some problems in post management and after-sales services. Therefore, though there is a problem of price and quality at present, domestic technologies of the management system should be developed for the long run. This study was conducted to develop an electronic identification unit for an automatic dairy farm management system. The developed system was consisted of a tag, a reader, a switching circuit, and a personal computer. The tag attachable to each individual cow was developed to transmit individual radio frequency(RF) code into the air with modulation of ASK(amplitude shift keying). And the switching circuit was added to avoid confusion on reception and transmittance. The reader attached to a feeding device was developed to transmit activating signal periodically and to identify code of the individual tag when the tag was approached to the device. The reader was consisted of an active filter, a detecter, a comparator and a microcontroller. The test result was feasible enough to apply it for the automatic farm management system and the identified maximum distance was about 37cm.

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관광 자원으로서 전통 음식의 매력성에 따른 구매 의사에 관한 연구 (Study on the Purchase Intention for Traditional Food according to the Attractiveness of Traditional Food as a Tourism Resource)

  • 박보미;윤유식;이경희
    • 동아시아식생활학회지
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    • 제19권5호
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    • pp.819-826
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    • 2009
  • The present study, we purposed to surveyed how much Korean natives' valuation of value traditional food as a tourism resource and their perception of traditional food, and to measured the attractiveness and potential of traditional food. For this purpose, we reviewed previously published studies research on traditional food and tourism resources, and conducted a questionnaire survey of urban citizens in Seoul on traditional food. Three hundred distributing 300 questionnaires were distributed and recovering 242 of them were returned. In this study, SPSS for Windows 16.0 was used for empirical analysis and the subjects' demographical characteristics were analyzed through frequency analysis. In addition, reliability analysis were performed to test the overall reliability of the empirical survey and collected data. Factor analysis was conducted to integrate variables, and the effect of the attractiveness of traditional food on purchase intention for traditional food was tested through multiple and simple regression analysis. Inquiring By surveying into the attractiveness of traditional food as a tourism resource, this study attempted to formulate a causal relation model among major variables, and examined the effects of the attractiveness of traditional food as a tourism resource on purchase intension based on Korean natives’ perception of and attitude toward traditional food, which is a Korean cultural heritage. Furthermore, and furthermore, made we provided suggestions for the improvement and development of traditional food.

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Chromosome Aberrations in Porcine Embryo Produced by Nuclear Transfer with Somatic Cell

  • Ah, Ko-Seung;Jin, Song-Sang;Tae, Do-Jeong;Chung, Kil-Saeng;Lee, Hoon-Taek
    • 한국수정란이식학회:학술대회논문집
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    • 한국수정란이식학회 2002년도 국제심포지엄
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    • pp.73-73
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    • 2002
  • Nuclear transfer (NT) techniques have advanced in the last years, and cloned animals have been produced by using somatic cells in several species including pig. However, it is difficult that the nuclear transfer porcine embryos development to blastocyst stage overcoming the cell block in vitro. Abnormal segregation of chromosomes in nuclear transferred embryos on genome activation stage bring about embryo degeneration, abnormal blastocyst, delayed and low embryo development. Thus, we are evaluated that the correlations of the frequency of embryo developmental rates and chromosome aberration in NT and In viかo fertilization (IVF) derived embryo. We are used for ear-skin-fibroblast cell in NT. If only karyotyping of embryonic cells are chromosomally abnormal, they may difficultly remain undetected. Then, we evaluate the chromosome aberrations, fluorescent in situ hybridization (FISH) with porcine chromosome 1 submetacentric specific DNA probe were excuted. In normal diploid cell nucleus, two hybridization signal was detected. In contrast, abnormal cell figured one or three over signals. The developmental rates of NT and IVF embryos were 55% vs 63%, 32% vs 33% and 13% vs 17% in 2 cell, 8 cell and blastocyst, respectively. When looking at the types of chromosome aberration, the detection of aneuploidy at Day 3 on the embryo culture. The percentage of chromosome aneuploidy of NT and IVF at 4-cell stage 40.0%, 31.3%, respectively. This result indicate that chromosomal abnormalities are associated with low developmental rate in porcine NT embryo. It is also suggest that abnormal porcine embryos produced by NT associated with lower implantation rate, increase abortion rate and production of abnormal fetuses.

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사물인터넷 기반 재난복구자원 관리 및 실시간 행동인지 모듈 개발 (IoT-Based Module Development for Management and Real-time Activity Recognition of Disaster Recovery Resources)

  • 최상윤;박주형;한수민;박진우;장태우;윤혁진
    • 한국전자거래학회지
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    • 제22권4호
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    • pp.103-115
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    • 2017
  • 세계적으로 자연재해의 빈도와 그 규모가 커지고 있으며, 그에 따른 피해도 늘어나고 있다. 몇 년 간 자연 재난 피해에 비추어 볼 때, 우리나라도 그러한 피해에서 자유롭지 못한 것이 사실이다. 본 연구에서는 재난 피해가 발생하였을 때, 복구자원을 효율적으로 관리하는 프로세스를 제안하였다. 사물인터넷 기술을 활용하여 실시간으로 자원 현황을 파악하고, 자원행동인지 모듈을 통하여 복구자원의 상태 및 움직임을 실시간으로 파악할 수 있도록 프로세스를 구성하였다. 또한 이를 실제로 구현하는데 필요한 데이터베이스 설계와 스마트폰 센서들을 이용한 자원행동인지 모듈을 개발하고 실험하였다. 이를 통하여 신속하고 효율적인 재난대응시스템 구축에 기여하고자 한다.

LTE-Advanced 네트워크에서 간섭 완화를 위한 FFFR 기반의 D2D 자원 할당 기법 (FFFR-Based Resource Allocation Mechanism for Interference Mitigation of D2D Communications in LTE-Advanced Networks)

  • 이한나;김향미;김상경
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
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    • 제4권1호
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    • pp.5-10
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    • 2015
  • LTE-A 네트워크에서 D2D 통신은 시스템의 용량 및 스펙트럼의 효율성을 향상시키는 유망한 기술이다. 전체 스펙트럼의 효율성을 향상시킬 수 있는 이유는 기지국이 이미 셀룰러 단말에 할당한 무선 자원을 D2D 통신에 할당하여 자원을 재사용할 수 있기 때문이다. 하지만 동일한 자원을 셀룰러 및 D2D 통신이 공유하여 사용함으로써 셀 내에 간섭이 발생할 수 있다. 따라서 동일한 자원을 사용하는 셀룰러 통신과 D2D 통신 간에 간섭 조정을 위한 적절한 자원 할당 기법이 필요하다. 특히, LTE-A 환경에 D2D 통신을 적용하기 위해서는 셀 내 간섭뿐만 아니라 셀 간 간섭 조정이 반드시 필요하다. 본 논문에서는 셀 간 간섭 완화를 위해서 주파수 재사용 패턴 기법 중 하나인 FFFR 기법을 사용하고, 셀 내 간섭 완화를 위해서는 기지국이 셀룰러 사용자가 이미 사용 중인 자원을 랜덤하게 선택하여 D2D 통신에 할당하는 D2D 자원 할당 알고리즘을 제안한다. 제안된 자원 할당 알고리즘의 성능평가를 위해 시뮬레이션을 수행하였으며, 셀 내 간섭 완화, 시스템 처리량 및 계산복잡도 등이 향상되는 것을 확인하였다.

Investigation of Tissue-Specific Distribution and Genetic Variation of Alfalfa Mosaic Virus and Chinese Artichoke Mosaic Virus in Chinese Artichoke (Stachys affinis miq.)

  • Ji-Soo Park;Dong-Joo Min;Tae-Seon Park;You-Seop Shin;Jin-Sung Hong
    • The Plant Pathology Journal
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    • 제40권4호
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    • pp.390-398
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    • 2024
  • The Chinese artichoke (Stachys affinis syn. S. sieboldii) is a widely cultivated crop, and its rhizome is used as a medicinal vegetable. To investigate the causes of viral diseases in Chinese artichokes, the infection rates of four virus species infecting Chinese artichoke were investigated. Since the Chinese artichoke propagates through its tuber, this study aimed to determine whether viral transmission to the progeny is possible through the tuber, by identifying the virus present in the tuber and investigating its accumulation. First, reverse transcription polymerase chain reaction analysis was performed to detect viruses using total RNA extracted from the flowers, leaves, and tubers of Chinese artichoke plants. Alfalfa mosaic virus (AMV) and Chinese artichoke mosaic virus (ChAMV) had high infectivity in Chinese artichoke and most plants were simultaneously infected with AMV and ChAMV. These viruses were present in all tissues, but their detection frequency and accumulation rates varied across different tissues of the Chinese artichoke. Also, we sequenced the coat protein (CP) genes of AMV and ChAMV to investigate genetic variations of virus between the leaf and tuber. It provides information on CP gene sequences and genetic diversity of isolates identified from new hosts of AMV and ChAMV. This study offers valuable insights into the distribution and spread of the ChAMV and AMV within Chinese artichoke plants, which have implications for the management and control of viral infections in crops.

A study of the interference measurement analysis between 3.4125GHz band broadcasting system and UWB wireless communication system

  • 송홍종
    • 정보통신설비학회논문지
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    • 제11권1호
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    • pp.10-15
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    • 2012
  • Ultra wideband (UWB) technologies have been developed to exploit a new spectrum resource in substances and to realize ultra-high-speed communication, high precision geo-location, and other applications. The energy of UWB signal is extremely spread from near DC (Direct Current) to a few GHz. This means that the interference between conventional narrowband systems and UWB systems is inevitable. However, the interference effects had not previously been studied from UWB wireless systems to conventional wireless systems sharing the frequency bands such as broadcasting system. This paper experimentally evaluates the interference from two kinds of UWB sources, namely an orthogonal frequency division multiplex UWB source and an impulse radio UWB source, to a broadcasting transmission system. The S/N ratio degradation of broadcasting system is presented. From these experimental results, we show that in all practical cases UWB system can be coexisted 35m distance in-band broadcasting network.

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RFID 군 적용방안 연구 (A Study on the Implementation of RFID for Korean Defense)

  • 이재열;김성원;최상영
    • 한국국방경영분석학회지
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    • 제31권1호
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    • pp.58-72
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    • 2005
  • RFID(Radio Frequency Identification) is one of key technologies in ubiquitous computing. RFID system comprises tag, reader, and computer application. The tag is a small electronic chip, which is attached to a thing such as item, pallet, container. The reader has an tiny antenna obtaining the identification information of the things by radio frequency, and provides the information to the computer application for a business. In this paper we have proposed the military application of RFID and its implementation policy for the Korean armed forces. We believe that The principle application area would be logistics TAV(total asset visibility) and resource management, and the implementation should be achieved step by step considering the advancement of RFID technology and government policy.

다중 셀 환경에서 주파수 오버레이를 이용한 대역 및 영역 분할 기법에서의 데이터 전송률 향상 (Increasing Throughput using Bandwidth and Region Division with Frequency Overlay over Multicell Environments)

  • 오태근;손혁민;이상훈
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.245-246
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    • 2008
  • A cell planning and resource allocation scheme called the proposed is presented for improving channel capacity and for maintaining a proper QoS (Quality of Service) over the downlink OFDMA (Orthogonal Frequency Division Multiple Access) system. Through an optimal combination of sectorization and frequency overlay, the proposed scheme accomplishes an improvement in both channel capacity and outage probability. In the simulation, the proposed scheme outperforms 3-sectorization in terms of throughput and outage probability.

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