• Title/Summary/Keyword: 4세대

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ATSC대응 DTV수상기 칩세트 개발

  • 최승종
    • Broadcasting and Media Magazine
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    • v.4 no.1
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    • pp.54-61
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    • 1999
  • 본 논문은 ATSC표준에 대응하는 DTV수상기용 칩세트에 대해서 논한다. 1세대 칩세트는 모두 5개로, VSB복조를 위한 두 개의 칩, 트랜스포트 역다중화칩, MPEG2 MP@HL 비디오 복호화칩, 디스플레이 프로세서등으로 구성되어있다. 1세대 칩세트는 0.35/0.6$\mu\textrm{m}$ 공정으로 모든 개발이 완료되었다. 개발한 칩들의 특징, 채택한 알고리즘 및 구현시 각종 파라미터들의 최적화방법들에 대해서 설명한다. 현재 2세대 칩세트가 개발 진행 중이며 대략적인 특징 및 주요 기능을 기술한다.

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Beyond-IMT-2000 부호화 기법

  • 신민호;임은정;송홍엽;김동구
    • Information and Communications Magazine
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    • v.18 no.6
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    • pp.74-91
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    • 2001
  • 본 고에서는 통신 시스템에 응용되고 있는 블록부호에 대한 소개와, IMT-2000 시스템의 표준화에서 채널 부호화 기법으로 규격에 반영된 길쌈부호(Convolutional code) 및 터보부호(Turbo code)에 대하여 소개하고, 현재 3세대 이동통신 표준화에서 논의중인 Hybrid ARQ(Adaptive Modulation and Coding), AMC(Adaptive Modulation and Coding) 기술에 대하여 설명한다. 그리고, 고속의 데이터 전송을 요하는 4세대 이동통신 시스템의 채널 부호화 기술로 현재 활발히 연구가 이루어지고 있는 Space-Time Code 및 LDPC(Low Density Parity Check Code)에 대해 소개하고, 차세대 이동통신 시스템의 채널 부호화 기술 전반에 대하여 전망한다.

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Design and Performance Evaluation of Cross-layer ARQ Mechanism Using Local Re-transmission Agent in Next Generation Mobile Networks (차세대 이동 망에서 지역 재전송 에이전트를 이용한 Cross-layer ARQ 메커니즘 설계 및 성능 평가)

  • So, Sang-Gp;Park, Man-Kyu;Lee, Jae-Yong;Kim, Byung-Chul;Kim, Dae-Young
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.8
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    • pp.50-58
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    • 2009
  • Fourth generation mobile communication network have the technology of extensive form include basic service technology and it has been developed from the radio access technology and network topology. Not only fourth generation mobile communication network have basically done new highspeed radio access technology which is suitable to high and low speed environment of transfer, but also it is possible that they have been made for freely vertical handover. ETRI also has made fourth generation mobile communication network which is WiNGS(Wireless Initiative for Next Generation Service) satisfied that demand. This paper is made by lossless handover method through the local retransmission ARQ agent that is one of the main technology of fourth generation mobile communication network. Lossless handover method through local retransmission ARQ agent has been basically made by WiNGS and it was better than original local retransmission of layer by simulation.

Studies on the Nymphal Parasitism, Haplogonatopus atratus Esaki at Hashimoto (Dryinidae) of the Small Brown Planthopper, Laodelphax striatellus Fallen (I) (애멸구 약충기생봉(Haplogonatopus atratus)에 관한 연구 (I))

  • Kim Jeong Bu;Kim Chang Hyo;Cho Dong Jin
    • Korean journal of applied entomology
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    • v.23 no.2 s.59
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    • pp.116-118
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    • 1984
  • This study was carried out to know the percentage of parasitism and host preference of Haplogonatopus atratus (Dryinidae) in the nymphs of small brown planthopper. The percentages of parasitism in the nymphal stage of planthopper at each generation were $19.2\%$ for overwinterd generation, $10.8\%$ for the 1st generation on barley field and $21.5\%$ for the 2nd generation on paddy field, respectively. The percents of the parasitism for the respective instars were $78.2\%$(3rd), $17.5\%$(End), and $4.2\%$(4th) when various developmental stages of the planthopper had been caged together. No parasitized individual was found for the instars of the 1st, the 5th and the adult.

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A Delphi Study for Constructing a Suicide Prevention Protocol for Male Baby Boomers (베이비붐세대 남성의 자살 예방 프로토콜 구성을 위한 델파이 연구)

  • Kim, Hee-SooK;Shin, Eun-Jeong;Kim, Gab-Yeon
    • Journal of Internet of Things and Convergence
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    • v.7 no.1
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    • pp.43-54
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    • 2021
  • Purpose: The purpose of this study was to construct a protocol for the prevention of suicide in male baby boomers. Methods: In order to construct the protocol, a three-step expert consensus process was carried out. The first step was to compose questions based on various research data. For this purpose, two professors of psychiatric mental health nursing and two advanced practitioner nurse of psychiatric mental health in the composition. The second step was to conduct the first Delphi survey on expert panelists. The survey period was from October 13, 2015 to November 1, 2015. The third stage, the second Delphi investigation was conducted from November 10 to December 4, 2015. Results: As a result of the survey, a total of 7 areas of protocol configuration items were derived. The derived items include the characteristics of male baby boomers, suicidal signs, suicide risk factors, suicide protection factors, suicide measurement tools, related organizations, and mental health promotion programs. Conclusion: This study can be used as a guideline when intervening suicide prevention of male baby boomers in community mental health centers.

Preparation and Termination of Carbosilane Dendrimer Based on Siloxane Tetramer (실옥산테트라머를 이용한 나뭇가지꼴 실란거대분자의 제조와 정지반응)

  • Kim, Chung Kyun;Park, Eun Mi
    • Journal of the Korean Chemical Society
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    • v.42 no.3
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    • pp.277-284
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    • 1998
  • Dendritic macromolecules of the first to fourth generation were synthesized, using alkenylation and hydrosilation cycles with allylmagnesium bromide and dichloromethylsilane as building blocks and siloxane tetramer $(Me(CH_2=CH)SiO)_4$, as core molecule. By the reaction of the dichloromethylsilyl-capped generation (G4P) with p-bromophenol, p-phenylphenol and lithium phenyethynylide, dendrimers with specific functions (G4P-BP (Mw: 16,300), G4P-PP (16,121), and CAP-PA (11,764)) have been produced. Analysis of new dendrimers by NMR, UV and MALD1 mass spectrometry suggests that they are pure and unified.

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Performance Analysis of OFDM for 4G Wireless Communications (4세대 무선통신을 위한 OFDM 전송기술의 성능분석)

  • Kim, Jae-Gak;Jeon, Mun-Seok
    • The KIPS Transactions:PartC
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    • v.8C no.4
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    • pp.437-442
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    • 2001
  • 무선, 컴퓨터와 인터넷 기술이 결합된 무선 인터넷 서비스는 급속히 확대될 것으로 전망되며, 이에 따라 음성은 물론 멀티미디어 통신까지 지원하는 고속의 전송기술이 요구되어지고 있다. 그러나 현재 사용하고 있는 DSSS(Direct Sequence Spread Spectrum) 전송방식은 전송속도의 제한 때문에 미래의 무선 환경하에서 충분치 않을 것으로 보인다. 본 논문에서는 차세대 전송기술로 부각되고 있는 고속의 무선 데이터 전송을 위한 OFDM(Orthogonal Frequency Division Multiplexing) 전송기술에 대해 고찰해 보고, 동일한 환경하에서 DSSS와 OFDM 전송장비의 성능 평가 실험을 실시하여 보았다. 무선 환경하에서의 DSSS/OFDM전송장비의 성능평가 결과, OFDM 전송기술을 사용한 장비의 성능이 성능면에서 훨씬 우월함을 보여주었다. 따라서 고속을 요하는 차세대 무선 인터넷의 전송기술로서 적합하게 사용될 수 있을 것으로 보인다.

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The Influence of Ageism and Age Integration on Perception of Intergenerational Conflict - A Comparison of Three Different Age Groups - (연령주의와 연령통합이 세대갈등인식에 미치는 영향 - 연령집단별 비교를 중심으로 -)

  • Chung, Soon Dool;Jeong, Ju Hi;Kim, Mi Ri
    • Korean Journal of Social Welfare
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    • v.68 no.4
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    • pp.5-24
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    • 2016
  • The purposes of this study were to investigate how ageism and age integration influence the perception of intergenerational conflict for each age group, and to seek alternatives to decrease intergenerational conflict. Study participants were divided into three groups based on their age: adolescence, middle age, and old age groups. For each group, the effects of ageism and age integration related variables on intergenerational conflict were examined using regression analysis. The results showed that there was no specific difference on the perception of intergenerational conflict by three different age groups; however, there were differences on influencing factors to explain the perception of intergenerational conflict. Among those factors, especially, the severity of the perception of age discrimination, which is one of ageism related variables, influenced the perception of intergenerational conflict for all age groups. That is, the more people perceived the severity of age discrimination, the more people perceived intergenerational conflict. The findings of this study are meaningful because this study revealed ageism and age integration could be causes to trigger intergenerational conflict.

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Studies on the Major Factors Affecting the Population of the Overwintered Pine Needle Gall Midge, Thecodiplosis japonensis Uchida et Inouye (솔잎혹파리의 월동후(越冬後) 밀도변동(密度變動)에 미치는 주요인자(主要因子)에 관(關)한 연구(硏究))

  • Chung, Yeong-Jin;Hyun, Jai-Sun
    • Korean journal of applied entomology
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    • v.25 no.1 s.66
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    • pp.1-9
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    • 1986
  • Periodical samplings were made in the fields, located Hwasong-Gun, Banwal-Myon, Doondai-Ri, for two years to study the major factors responsible to the population of the overwintered pine needle gall midge, Thecodiplosis japonensis Uchida et Inouye. The population densities of the overwintered larvae reduced greatly at the time of pupation and the changing patterns seemed to be influenced by environmental conditions. The estimated 50% pupation day was about two weeks earlier for the 1980 generation compared with the 1979 generation, and much higher average and the daily maximum temperatures in 1981 affected on the development of the larvae. The relative emergence rates were 14.1% for 1979 and 14.9% for 1980 generation. The relative emergence rates(Y) were affected by the moisture contents of soil ($X_1$) and its variance $(X_2),\;Y=-68.41+4.3206X_1-0.6887X_2$. The relative emergence rates seemed to be decreased with the increased variance of the moisture contents of soil. Percents of needle gall were 49.63% for 1980 and 86.87% for 1981 generation.

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