• 제목/요약/키워드: Diversity

검색결과 11,467건 처리시간 0.037초

블록호핑 SC-FDMA 시스템을 위한 순환지연 다이버시티의 지연값 결정 (Delay Determination for Cyclic Delay Diversity for Block-Hopping SC-FDMA Systems)

  • 임민중
    • 대한전자공학회논문지TC
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    • 제46권1호
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    • pp.72-82
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    • 2009
  • OFDMA 시스템에서는 순환지연 다이버시티는 다이버시티 효과에 의해서 시스템 성능을 증대시킨다. 그러나 블록호핑 SC-FDMA 시스템에서 순환지연 다이버시티의 적용은 다이버시티 효과에 의한 성능 증대효과와, 채널이 주파수 선택적이 됨으로-인한 성능의 감소효과가 동시에 발생한다. 따라서 시스템 성능을 최대화하기 위해서는 순환지연 다이버시티의 지연간을 적절히 선택하는 것이 필요하다. 이 논문에서는 이 두 가지 상반되는 효과와 블록호핑 SC-FDMA 시스템에서 순환지연 다이버시티를 적용할 때 순환지연값을 결정하는 방법에 대해 논의한다.

주파수 다이버시티를 이용한 순환 지연 다이버시티 OFDM 시스템의 성능 향상 연구 (A study on performance enhancement of cyclic delay diversity OFDM system using frequency diversity)

  • 정혁구
    • 한국통신학회논문지
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    • 제37권3A호
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    • pp.135-140
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    • 2012
  • 이 논문은 순환 지연 다이버시티 OFDM 시스템의 성능을 향상시키기 위하여 주파수 다이버시티를 적용하는 알고리즘을 제안한다. OFDM 시스템에서 주파수 다이버시티 적용은 동일한 심볼을 상관관계가 없는 부반송파로 반복 전송하는 것으로 수행되며, 반복 전송 회수에 비례하여 변조 레벨을 증가시켜서 종래의 전송 시스템의 성능과 비교한다. 이 방법은 순환 지연 다이버시티 알고리즘과 같이 송신기 개수가 많아짐에 따라 수신기에서 부가적인 특별한 하드웨어가 필요하지 않다는 동일한 장점이 있게 되며, 성능 시험을 위해서 다중 송수신 안테나 환경하에서 모의 실험을 수행하였다. 제안하는 알고리즘은 종래의 순환 지연 다이버시티를 활용한 OFDM 시스템과 비교하여 저밀도 변조 레벨에서 성능 향상이 현저함을 보여준다.

R&D 프로젝트 팀 다양성과 팀 성과간의 관계: 제해결스타일 및 상호의존성의 조절효과 (R&D Project Team Diversity and Team Performance : Investigating the Moderating Effect of Innovative Problem Solving Style and Interdependence)

  • 박오원
    • 기술혁신학회지
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    • 제16권4호
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    • pp.913-936
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    • 2013
  • 다양성의 중요성이 강조되면서 최근의 연구들은 다양성과 성과간의 직접효과에 대한 분석에서 상황적 요인의 효과를 분석하는 데 연구의 초점을 맞추고 있다. 본 연구에서는 다양성과 성과간의 관계를 보다 명확하게 파악하기 위해서 혁신적 문제해결 스타일과 상호의존성(과업, 목표, 결과)을 상황요인으로 제시한 후 이들 변수들의 조절효과를 분석하였다. R&D 연구소의 75개 프로젝트 팀을 대상으로 실증 분석한 결과 팀원들이 혁신적 문제해결 스타일을 가져갈 수록 다양성과 프로젝트 성과간의 긍정적 관계는 더욱 높아졌다. 또한 세 가지 유형의 상호의존성도 다양성과 프로젝트 성과간의 관계를 긍정적으로 조절하는 것으로 나타났다. 마지막으로 연구결과에 대한 시사점과 향후 연구방향에 대하여 논의하였다.

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The Effect of Service Quality and Product Diversity on Customer Loyalty: The Role of Customer Satisfaction and Word of Mouth

  • TJAHJANINGSIH, Endang;NINGSIH, Dewi Handayani Untari;UTOMO, Agus Prasetyo
    • The Journal of Asian Finance, Economics and Business
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    • 제7권12호
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    • pp.481-490
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    • 2020
  • Batik industry is a business activity oriented towards customer loyalty and is demanded to show an increasing diversity of products with various motives designed to prevent customers from moving to other companies. Therefore, the purpose of this study is to develop a theoretical approach in solving problems in the relationship between service quality and product diversity on satisfaction and word of mouth (WoM) and its impact on customer loyalty. Furthermore, this study also examined the mediating effects of satisfaction and WoM in the relationship between service quality and product diversity on customer loyalty. This research's object took the customers of Batik Semarangan Craftwork, Indonesia, with the phenomenon of always developing creative and innovative Batik motif designs that can be accepted by the market without leaving Semarang's uniqueness. The total sample was 98 customers. The results of the study showed that service quality and product diversity positively affected satisfaction and WoM and had a positive effect on customer loyalty. Besides, satisfaction and WoM had a mediating effect on the effect of service quality and product diversity on loyalty. Thus, it is essential for management to create and increase customer loyalty by paying attention to service quality, product diversity, satisfaction, and WoM.

RAPD에 의한 층층나무의 유전적 다양성과 집단구조 (Genetic Diversity and Population Structure of Comus controversa Hemsley Using RAPD)

  • 문성기;허만규
    • 생명과학회지
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    • 제18권2호
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    • pp.175-179
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    • 2008
  • Cornus controversa is a long-lived woody species mostly distributed in East Asia. Random amplified polymorphic DNA (RAPD) markers were used to investigate the genetic diversity and population structure of Korean populations of this species. A high level of genetic variation was found in seven populations of C. controversa. The mean genetic diversity (H) was 0.222 across populations, varying from 0.200 to 0.238. Eighty of the 93 loci (86.0%) showed detectable polymorphism in at least one population. Total genetic diversity values ($H_T$) varied between 0.192 and 0.231, giving an average overall polymorphic loci of 0.212. The interlocus variation of genetic diversity within populations ($H_S$) was high (0.167). Mean of genetic diversity in C. controversa was higher than average values for species with similar life history traits. The sexual reproduction, perennial habitat, and longevity are proposed as possible factors contributing to high genetic diversity. On a per locus basis, the proportion of total genetic variation due to differences among populations ($G_{ST}$) ranged from 0.169 to 0.278 with a mean of 0.216, indicating that about 21.6% of the total genetic variation was among populations. An indirect estimate of the number of migrants per generation (Nm=1.893) indicated that gene flow was extensive among Korean populations of C. controversa.

Diversity of Fungi in Soils with Different Degrees of Degradation in Germany and Panama

  • Rosas-Medina, Miguel;Macia-Vicente, Jose G.;Piepenbring, Meike
    • Mycobiology
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    • 제48권1호
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    • pp.20-28
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    • 2020
  • Soil degradation can have an impact on the soil microbiota, but its specific effects on soil fungal communities are poorly understood. In this work, we studied the impact of soil degradation on the richness and diversity of communities of soil fungi, including three different degrees of degradation in Germany and Panama. Soil fungi were isolated monthly using the soil-sprinkling method for 8 months in Germany and 3 months in Panama, and characterized by morphological and molecular data. Soil physico-chemical properties were measured and correlated with the observed values of fungal diversity. We isolated a total of 71 fungal species, 47 from Germany, and 32 from Panama. Soil properties were not associated with fungal richness, diversity, or composition in soils, with the exception of soil compaction in Germany. The geographic location was a strong determinant of the soil fungal species composition although in both countries there was dominance by members of the orders Eurotiales and Hypocreales. In conclusion, the results of this work do not show any evident influence of soil degradation on communities of soil fungi in Germany or Panama.

Effect of Cooperative and Selection Relaying Schemes on Multiuser Diversity in Downlink Cellular Systems with Relays

  • Kang, Min-Suk;Jung, Bang-Chul;Sung, Dan-Keun
    • Journal of Communications and Networks
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    • 제10권2호
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    • pp.175-185
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    • 2008
  • In this paper, we investigate the effect of cooperative and selection relaying schemes on multiuser diversity in downlink cellular systems with fixed relay stations (RSs). Each mobile station (MS) is either directly connected to a base station (BS) and/or connected to a relay station. We first derive closed-form solutions or upper-bound of the ergodic and outage capacities of four different downlink data relaying schemes: A direct scheme, a relay scheme, a selection scheme, and a cooperative scheme. The selection scheme selects the best access link between the BS and an MS. For all schemes, the capacity of the BS-RS link is assumed to be always larger than that of RS-MS link. Half-duplex channel use and repetition based relaying schemes are assumed for relaying operations. We also analyze the system capacity in a multiuser diversity environment in which a maximum signal-to-noise ratio (SNR) scheduler is used at a base station. The result shows that the selection scheme outperforms the other three schemes in terms of link ergodic capacity, link outage capacity, and system ergodic capacity. Furthermore, our results show that cooperative and selection diversity techniques limit the performance gain that could have been achieved by the multiuser diversity technique.

마이크로세틀라이트 마커 분석을 이용한 남서태평양 일대에 서식하는 남방톱날꽃게(Scylla serrata)의 유전적 다양성 (Genetic Diversity of the Mud Crab Scylla serrata in Micronesia based on Microsatellite Marker Analysis)

  • 장요순;이순길;노충환;오승용
    • Ocean and Polar Research
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    • 제31권4호
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    • pp.319-326
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    • 2009
  • Analysis of four microsatellite markers from Mud Crab Scylla serrata revealed that there is high level of genetic diversity within this species. Genetic diversity of S. serrata was calculated using allele diversity, observed heterozygosity, expected heterozygosity (Het-exp), polymorphic information content, gene differentiation and Nei's $D_{A}$ distance. Mean polymorphic information content value was 0.797, which reflected high level of polymorphism across the loci of S. serrata. The Palau population has the highest genetic diversity (Het-exp=0.871), while the Kosrae population has the lowest genetic diversity (Hetexp=0.806). However, the geographical genetic distance among S. serrata populations from Yab, Chuuk, Pohnpei, Kosrae, and Palau were low (0.2009${\sim}$0.3350). These results suggest that despite their wide distribution, S. serrata are no different in geographical genetic diversity within the five sampled locations.

다양한 가족유형에 대응하는 사회통합적 주거모델개발을 위한 주거현황 분석연구 (Analysis on the current housing types for development of social integrated housing models responding to family diversity)

  • 김경연;이수진;이연숙
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2008년도 춘계학술발표대회 논문집
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    • pp.140-144
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    • 2008
  • While we go through a rapid change in society, family types composing social relationship underwent lots of changes. Recently the range of family is included not only families on the basis of blood relationship but also single family, a one-parent family and non-blood relationship family. Now we need not unified types of housing but social integrated housing models responding to family diversity. The purpose of this study is that examine family diversity through social statistics and demography and grasp the current housing types responding to family diversity. The features of family diversity are reducing the number of family member and turning up a unformal family type. At the social statistics and demography in 2005, the number of family member is only 2.9 people per family. Due to decline of birth rate and change of marriage consciousness, various family types appear and increase such as single family, a one-parent family and non-blood relationship family. But there is lack of housing types responding to such family diversity. This study will be a basic research to develop social integrated housing models responding to family diversity. Housing must be sensitive to change of family type, so it responds our needs based on thorough understanding on various housing life.

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