• 제목/요약/키워드: Research Diversity

검색결과 4,118건 처리시간 0.029초

Linear Diversity Analysis for M-ary Square Quadrature Amplitude Modulation over Nakagami Fading Channels

  • Yoon, Dong-Weon;Chang, Dae-Ig;Kim, Nae-Soo;Woo, Hoon-Shik
    • ETRI Journal
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    • 제25권4호
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    • pp.231-237
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    • 2003
  • We derive and analyze the exact closed-form expression for the average bit error probability (BEP) of M-ary square quadrature amplitude modulation (QAM) for diversity reception in frequency-nonselective Nakagami fading. A maximal ratio combining (MRC) diversity technique with independent or correlated fading cases are considered. Numerical results demonstrate error performance improvement with the use of MRC diversity reception. The presented new expressions offer a convenient way to evaluate the performance of M-ary square QAM with an MRC diversity combiner for various cases of practical interest.

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The Performance Improvement of a Multicarrier DS-CDMA System Using both Time-Diversity and Frequency Offset

  • Kim, Ki-Doo;Oh, Jung-Hun;Milstein, Laurence B.
    • ETRI Journal
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    • 제21권4호
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    • pp.29-40
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    • 1999
  • In this paper, we show the robustness of a proposed system using both a frequency diversity and a time diversity effect when the channel assumptions are relaxed such that all sub-bands are not independent fading. We take time-repetition coding with interleaving such that the repetition code symbols are spaced sufficiently far apart to guarantee time diversity. We also incorporate offset multicarriers into a proposed multicarrier DS-CDMA system in a different way compared to that of [10] to reduce the total multiple access interference. When we take a convolutional encoder instead of a time-repetition encoder, and again use both time diversity and frequency offset, then we can obtain the significant performance gain.

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공학설계에서 인지적 팀 다양성, 공학설계 자기효능감 및 팀 창의성의 관계 (Relationships among Cognitive Team Diversity, Engineering Design Self-Efficacy, and Team Creativity in Engineering Design)

  • 안정호;임지영
    • 공학교육연구
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    • 제18권6호
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    • pp.11-17
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    • 2015
  • This study examined the moderating effect of engineering design self-efficacy on the relationship between cognitive team diversity and team creativity. For this study, 377 mechanical engineering students in engineering design classes were included in the analysis. The results showed that both cognitive team diversity and engineering design self-efficacy were positively correlated with team creativity. The analysis of moderating effect indicated that engineering design self-efficacy further reinforced the positive relationship between cognitive team diversity and team creativity. Finally, implications and limitations of this study were explored.

Ownership Concentration, Board Education Diversity, and Environmental Accounting Disclosure in Kenyan Listed Firms. Moderation Approach

  • TARUS, John Kipngetich
    • 웰빙융합연구
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    • 제3권1호
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    • pp.1-10
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    • 2020
  • The purpose of this study was to examine the moderating effect of board education diversity on the relationship between ownership concentration and environmental accounting disclosure. The study was driven by stakeholder's theory. The longitudinal research design was adopted in the study. The study targeted 27 listed firms from 2008 to 2017. Panel regression analysis results indicated ownership concentration (β = -.131, ρ<.05) had a negative and significant effect on environmental disclosure in Kenyan firms. However, Board education diversity positively moderated the relationship between ownership concentration (β=.138, ρ<.05) and environmental accounting disclosure. Thus, board education diversity is an enhancing moderator in the relationship between ownership concentration and environmental accounting disclosure. The findings validate stakeholder theory's proposition. The study recommends that firms listed in the NSE ought to diffuse ownership concentration, and their boards should be well educated and experienced to enhance environmental accounting disclosure.

Adaptive Channel-Matched Extended Alamouti Space-Time Code Exploiting Partial Feedback

  • Badic, Biljana;Rupp, Markus;Weinrichter, Hans
    • ETRI Journal
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    • 제26권5호
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    • pp.443-451
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    • 2004
  • Since the publication of Alamouti's famous space-time block code, various quasi-orthogonal space-time block codes (QSTBC) for multi-input multi-output (MIMO) fading channels for more than two transmit antennas have been proposed. It has been shown that these codes cannot achieve full diversity at full rate. In this paper, we present a simple feedback scheme for rich scattering (flat Rayleigh fading) MIMO channels that improves the coding gain and diversity of a QSTBC for 2$^n$ (n=3, 4, ${\cdots}$) transmit antennas. The relevant channel state information is sent back from the receiver to the transmitter quantized to one or two bits per code block. In this way, signal transmission with an improved coding gain and diversity near to the maximum diversity order is achieved. Such high diversity can be exploited with either a maximum-likelihood receiver or low-complexity zero-forcing receiver.

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3'UTR Diversity: Expanding Repertoire of RNA Alterations in Human mRNAs

  • Dawon Hong;Sunjoo Jeong
    • Molecules and Cells
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    • 제46권1호
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    • pp.48-56
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    • 2023
  • Genomic information stored in the DNA is transcribed to the mRNA and translated to proteins. The 3' untranslated regions (3'UTRs) of the mRNA serve pivotal roles in post-transcriptional gene expression, regulating mRNA stability, translation, and localization. Similar to DNA mutations producing aberrant proteins, RNA alterations expand the transcriptome landscape and change the cellular proteome. Recent global analyses reveal that many genes express various forms of altered RNAs, including 3'UTR length variants. Alternative polyadenylation and alternative splicing are involved in diversifying 3'UTRs, which could act as a hidden layer of eukaryotic gene expression control. In this review, we summarize the functions and regulations of 3'UTRs and elaborate on the generation and functional consequences of 3'UTR diversity. Given that dynamic 3'UTR length control contributes to phenotypic complexity, dysregulated 3'UTR diversity might be relevant to disease development, including cancers. Thus, 3'UTR diversity in cancer could open exciting new research areas and provide avenues for novel cancer theragnostics.

Species Diversity of Endophytic Fungi Isolated from Taxus cuspidata Inhabiting Mt. Hallasan, Korea

  • Jae-Eui Cha;Hyeok Park;Ahn-Heum Eom
    • 한국균학회지
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    • 제51권4호
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    • pp.419-428
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    • 2023
  • Several endophytic fungal strains were isolated from Taxus cuspidata and identified by molecular analysis of the internal transcribed spacer and RNA polymerase II second largest subunit. This study aimed to determine the relative abundance and compare the species diversity of endophytic fungal communities within needle leaves and twigs. We identified a total of 49 endophytic fungal species. Notably, two species, Trichoderma dingleyae and Xylaria cubensis, were discovered to be previously unrecorded in Korea. The fungal communities in both plant tissues demonstrated distinct species composition. Differences were observed in the relative abundance and species diversity index between needle leaves and twigs. Our findings suggest that the host plant tissues influence the species diversity of endophytic fungal communities.

경쟁과 다양성: 방송관련법의 목적의 관점 (Competition and Diversity: Perspective of the Objectives of Broadcasting-related Laws)

  • 홍대식
    • 법제연구
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    • 제44호
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    • pp.63-101
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    • 2013
  • 이 글에서는 먼저 경쟁과 다양성이 미디어 정책의 구체적인 수단을 규정한 방송관련법이 추구하는 주된 목적이 된다는 것을 전제로 하여 각각의 개념과 구성요소 그리고 그 제도적 구현의 모습을 살펴보고, 특정분야의 경쟁법으로서의 방송관련법에서는 경쟁 목적이 차별성 요인을 갖는 한편 다양성 가치도 특수성을 갖는다는 논의를 전개한다. 다음으로 경쟁과 다양성 가치를 조화롭게 실현하기 위해서는 방송시장 특유의 구조적 규제수단을 포함하는 특별한 경쟁규칙이 필요하다고 전제하면서, 방송관련법상 경쟁 목적 규제와 다양성 목적 규제에 대하여 개선되어야 할 방향을 다음과 같이 제시한다. 첫째, 경쟁 목적 규제의 개선 방안이다. 사전적인 상태적 규제로서의 시청점유율 규제와 사후적인 행위규제로서의 금지행위 규제는 다양성 가치를 추구하면서도 원인적 규제를 대체하는 데 중요한 역할을 할 수 있다. 이를 위하여 공정거래법의 위법성 판단방식을 유추하여 다양성 관련 요소를 금지행위의 위법성 판단기준의 고려요소로 하는 방식을 구체적으로 개발할 필요가 있다. 둘째, 다양성 목적 규제의 개선 방안이다. 이는 규제 목적의 설정, 대체가능한 규제수단의 식별, 규제 목적에 맞는 규제수단과 규제수준의 선택이라는 3가지 관점에서 검토될 수 있다. 이러한 관점에서 다양성 가치가 단순한 수사적 도구에 그치지 않고 평가 및 분석 도구로 사용될 수 있는 제도적 수단 위주로 규제 틀을 개선하는 한편, 경쟁과 같은 경제적 목적과의 조화를 고려할 때 불합리해 보이는 규제에 대하여는 이를 유지할 것인가 또는 어느 정도로 유지할 것인가를 신중하게 재검토해야 한다.

대학생이 인식하는 가족 다양성 수용도에 영향을 미치는 요인 (The acceptance of family diversity among college students and related variables)

  • 이선영;정유진
    • 한국가족관계학회지
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    • 제23권3호
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    • pp.3-29
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    • 2018
  • Objectives: The purpose of this study was to investigate the acceptance of family diversity among college students and related variables. Method: Data were collected by a structured questionnaire with 280 students who attended in three universities located in J province. SPSS Statistics Program version 24.0 was used to analyze the collected data. To answer the research questions, descriptive statistics, t-test, F-test, Pearson's correlation analyses, and regression analyses were performed. Results: The major results of the survey were summarized as below. First, the acceptance of family diversity among college students was slightly higher than the middle level(M=12.11). Most students accepted nuclear family as a typical family. More than half of the students accepted single parent families, adaptive families, step families, unmarried mother families, childless couples, homosexual families, elderly women living alone, and families composed of siblings as a family. Second, there was a significant difference by religiosity. Students without religion were higher than their counterparts with religion in a level of family diversity acceptance. Among the individual factors, third, a level of traditional family value had a significant negative effect on a level of family diversity acceptance. And perspective taking had a positive effect on a level of family diversity acceptance. Fourth, among the family factors, parent-child open communication did not affect a level of family diversity acceptance. However, parents' gender egalitarian beliefs had a significant positive effect on a level of family diversity acceptance. Lastly, regarding the relative effects of the personal and family factors, the traditional family value had the largest effect on a level of family diversity acceptance among college students. Conclusions: Base on these results, the implications and limitations of the study were discussed.

Mitochondrial DNA Diversity and Origin of Red Chittagong Cattle

  • Bhuiyan, M.S.A.;Bhuiyan, A.K.F.H.;Yoon, D.H.;Jeon, J.T.;Park, C.S.;Lee, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권10호
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    • pp.1478-1484
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    • 2007
  • To determine the origin and genetic diversity of Red Chittagong (RC) cattle in Bangladesh, we analyzed mitochondrial DNA displacement loop (D-loop) sequences of 48 samples along with 22 previously published sequences from Bos indicus and Bos taurus breeds. Twenty five haplotypes were identified in RC cattle that were defined by 44 polymorphic sites and nucleotide diversity was $0.0055{\pm}0.0026$. The estimated sequence divergence times between RC and other zebu cattle breeds studied ranged between 22,700-26,900 years before present (YBP) which, it is suggested, predate domestication of RC cattle. Furthermore, it is assumed that introgressions have occurred in this breed mainly from Indian zebu breeds in the recent millennia. The phylogenetic studies showed RC cattle clustered with Bos indicus lineage with two distinct haplogroups representing high genetic variability of this breed. These findings can be used for designing proper breeding and conservation strategies for RC cattle in Bangladesh.