• Title/Summary/Keyword: Selection Diversity

Search Result 527, Processing Time 0.044 seconds

Capacity Increasement of Trellis Coded 16 QAM Multi-Carrier CDMA System due to SC/MRC Diversity in Multiuser Interference and Rician Fading Channel.

  • 노재성;강희조;김춘길;김언곤;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.25 no.3A
    • /
    • pp.362-374
    • /
    • 2000
  • In this paper, trellis coded 16 QAM Multi-Carrior CDMA system is proposed, Using the equivalent signal-to-noise plus interference Power ratio (SNIR) of Multi-Carrier CDMA system in the reverse link, capacity and BER performance of trellis coded 16 QAM Multi-Carrier CDMA system are analyzed taking into account the number of multi-carrier, the number of multiple access user, the number of SC/MRC diversity branch, and Rician fading parameter in multiuser interference and Rician fading channel. And the capacity and the BER performance of trellis coded 16 QAM Multi-Carrier CDMA system using selection combining (SC) and maximal ratio cabining (MRC) diversity are numerically compared. Obtained results show that the capacity of proposed system depends on the number of multi-carrier. ti is found that the trellis coded 16 QAM Multi-Carrier CDMA system with SC/MRC antenna diversity scheme is efficient to combat multipath fading and to increase the maximum number of users in high speed data communication. With the results of analysis. MRC diversity technique provides the performance fro high speed data communications. Finally, we present a numerical approach to derive the capacity and the BER performance and to find the maximum number of multiple access user for Multi-Carrier system in multiuser interference and Rician fading channel.

  • PDF

Diversity of Chinese Indigenous Goat Breeds: A Conservation Perspective - A Review -

  • Li, M.H.;Li, K.;Zhao, S.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.17 no.5
    • /
    • pp.726-732
    • /
    • 2004
  • In this manuscript, a review of the diversity of Chinese indigenous goat breeds according to data from body stature and appearance, chromosome group, blood proteins, DNA molecular markers (mitochondria DNA, random amplified polymorphic DNA, microsatellite DNA, major histocompatibility complex) has been introduced. All of these provide efficient tools for the diversity analysis of Chinese indigenous goat breeds and are very important for biodiversity conservation, restoration of declining goat breeds, the priority defining in Chinese indigenous goat breeds' protection and the selection of nature preservation zones. Many Chinese indigenous goat breeds with small population size in the isolated mountains or reservoir areas are verging the potential threat of extinction, effectively lost with the rapid destroying of ecological environment. On the other hand, as a result of the introduction of modern commercial goat breeds and shortage of effective conservation, some populations, such as Small-xiang goat and Tibetan goat decrease rapidly in number of sires. In the interests of the long-term future of the goat breeds in China, conservation of goat breeds' genetic resources should be considered urgently and some conservation measures should be adopted. In addition, the continuing development of molecular biology will further enhance conservation of diversity of Chinese indigenous goat breeds.

Diversification and domain evolution of molluskan metallothioneins: a mini review

  • Nam, Yoon Kwon;Kim, Eun Jeong
    • Fisheries and Aquatic Sciences
    • /
    • v.20 no.6
    • /
    • pp.8.1-8.18
    • /
    • 2017
  • Background: Metallothionein (MT) is a multifunctional protein playing important roles in homeostatic regulation and detoxification of metals. Mollusk species have been considered as useful sentinel platforms for MT-based biomarker approaches, and they have been reported to display an extraordinary structural diversity of MT proteins. However, potential diversity of molluskan MTs has not been fully explored and recent updates have suggested the need of revision of evolutionary hypothesis for molluskan MTs. Results: Based on bioinformatic analysis and phylogenetic evidences, novel divergence mechanisms and paths were hypothesized in both gastropod and bivalve MT groups. Our analyses are suggestive of the taxon- or lineage-specific domain multiplication/duplication from the ancestral or prototypic MT. Diversification and selection of molluskan MTs might be driven by the needs for acquiring metal selectiveness, specialized novel function, and improved capacity of metal detoxification under environmentally stressed conditions. Conclusion: The structural diversity and variations of molluskan MTs are significantly larger than previously understood. Undoubtedly, molluskan MTs have undergone dynamic divergent processes in their evolutionary histories, giving rise to the great diversity of domain structures in extant MT isoforms. Novel evolutionary paths for molluskan MTs newly proposed in this review could shed additional light onto the revision of the hypothesis for evolutionary differentiation of MTs in the molluskan lineage.

Diversity Combining Techniques for DPSK Signals in Nakagami Fading Channels (나카가미 페이딩 채널에서 DPSK 신호의 다이버시티 합성기법)

  • 김창환;한영열
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.25 no.1A
    • /
    • pp.34-42
    • /
    • 2000
  • In this paper, the closed form expression for the average bit error probability(BER) is derived for diversity reception using an L-branch maximal ratio combining(MRC) system which has same fading index and different fading index. Also, the BER to have same average power and Nakagami m-distribution for a generalized selection combining(SC) is derived, whereby the signal with the largest amplitude is selected from the original diversity branches in the channel, the order statistics is applied. Especially, when L is 1 in a selective diversity, the derived expression leads to that of DPSK in which SC is not applied in Nakagami fading. Changing the diversity branch L and fading index m, we compare the performance of MRC and SC.

  • PDF

Genetic Diversity Analysis of Maintaining Lines for Kenyan Sunflower (Helianthus annus L.) Using Allele Specific SSR Markers

  • Mwangi, Esther W.;Lee, Myung-Chul;Sung, Jung Suk;Marzougui, Salem;Bwalya, Ernest C.
    • Proceedings of the Plant Resources Society of Korea Conference
    • /
    • 2019.04a
    • /
    • pp.61-61
    • /
    • 2019
  • In any crop breeding program Selection and use of genetically diverse genotypes to develop cultivars with a broad genetic base is important. Molecular markers play a major role in selecting diverse genotypes. Molecular breeding programs of the crop can be made more efficient by use of molecular markers. The present study was done with an aim of analyzing genetic diversity and the population structure in 24 accessions of sunflower (Helianthus annus L.) from Kenya genetic diversity using 35 EST-SSR and gSSR primers.Out of the 35 markers 3 were not polymorphic as they indicated Polymorphic Information content( PIC) of value 0.00 and so the data analysis was done using 32 markers . The 32 set of markers used produced 29 alleles ranging from 2 to 7with a mean of 3.0 alleles per locus.The average value of polymorphic information contents(PIC) were 0.3 .Genetic diversity analysis using these markers revealed 3 major clusters. This result could be useful for designing strategies to make elite hybrid and inbreeding of crossing block for breeding and future molecular breeding programs to make elite variety.

  • PDF

Gender Diversity, Institutional Ownership and Earning Management: Case on Distribution Industry in Indonesia

  • ZUBAIDAH, Siti;IRAWAN, Dwi;SUMARWIJAYA, Sumarwijaya;WIDYASTUTI, Aviani;ARISANTI, Ike
    • Journal of Distribution Science
    • /
    • v.19 no.11
    • /
    • pp.17-25
    • /
    • 2021
  • Purpose: This study aims to examine the effect of gender diversity and institutional ownership on earnings management in distribution industry sub-sector companies listed on the Indonesia Stock Exchange in 2017-2018. Research design, data and methodology: This research is case study research, where the population in this study are all distribution sub-sector companies listed on the IDX in 2017-2018. The sample selection technique used was purposive sampling and obtained 74 companies with the 2017-2018 research period. Multiple linear regression analysis was used in this study, using Stata 17. Results: The results of this study indicate that: 1) Gender diversity has a negative effect on earnings management. 2) Institutional ownership has a negative effect on earnings management. Conclusions: This study contributes to the agency theory where gender diversity and institutional ownership can reduce the agency conflict that the shrinkage of earnings management. These results indicate that companies in which there are female directors will reduce earnings management practices, this is due to the attitude of female directors who tend to avoid risk. The results also show that institutional ownership will also lead to reduced levels of earnings management, because institutional investors will increase its oversight of the company.

The Impact of the Diversity Management on the Workforce Composition and Financial Performance (다양성관리가 조직인력구성과 재무성과에 미치는 영향)

  • Sung, Sang-Hyeon;Kim, Dae-Lyong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.1
    • /
    • pp.110-124
    • /
    • 2011
  • Even though Korea has long experienced single race/ethnic demographic composition, the recent rapid change of demographic diversity will have powerful impact on the HRM(human resource management) in the future. In this research we find the influence of the diversity friendly HRM to the human resource practices using the data of WPS(Workplace Panel Survey) of Korea Labor Institute. If the training for women is high, the density of the woman increased. The performance pay is introduced, then the density of the disabled person would be increased. The foreign workforce was also increased if the company used more selection methods. But the HRM practices such as talent management, yearly-based compensation systems, and appraisal program which has a tendency to reduce diversity have no significant influence to the financial performance. This findings imply that the management team should introduce the effective HRM systems to manage diverse human resources after considering the organizational culture and business environment. This research intends to find the diversity friendly HRM practices and hope to help the efforts of the management team to find effective management methods.

Antenna Selection and Shuffling for DSTTD Systems with Correlated Transmit-Antenna (송신 안테나 사이에 상관관계가 있는 DSTTD 시스템에서 안테나 선택과 뒤섞는 기법)

  • Joung, Jin-Gon;Jeong, Eui-Rim;Lee, Yong-Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.32 no.8C
    • /
    • pp.767-774
    • /
    • 2007
  • A new transmit antenna selection and shuffling($AS^2$) method for spatially correlated double space time transmit diversity(DSTTD) systems is proposed. The proposed method allows dumb antennas and the superposition of multiple signals at the same transmit antenna, whereas the conventional methods consider the antenna shuffling(AS) only. According to the simulation result, the proposed method provides a 1.8 dB signal-to-noise ratio(SNR) gain over the conventional methods for spatially correlated transmit antennas. Although the number of candidates for $AS^2$ is much higher than that of AS, it is found that the number of candidates for $AS^2$ can be reduced to 36 by using the characteristics and properties of preprocessing matrices, and among them, only 6 candidates are almost always chosen. Next, we empirically compare the bit-error-rate (BER) performance of the proposed method with the conventional spatial multiplexing(SM) technique with antenna selection. Simulation results show that the proposed method outperforms the SM technique.

Genetic Diversity of a Natural Population of Apple stem pitting virus Isolated from Apple in Korea

  • Yoon, Ju Yeon;Joa, Jae Ho;Choi, Kyung San;Do, Ki Seck;Lim, Han Cheol;Chung, Bong Nam
    • The Plant Pathology Journal
    • /
    • v.30 no.2
    • /
    • pp.195-199
    • /
    • 2014
  • Apple stem pitting virus (ASPV), of the Foveavirus genus in the family Betaflexiviridae, is one of the most common viruses of apple and pear trees. To examine variability of the coat protein (CP) gene from ASPV, eight isolates originating from 251 apple trees, which were collected from 22 apple orchards located in intensive apple growing areas of the North Gyeongsang and North Jeolla Provinces in Korea, were sequenced and compared. The nucleotide sequence identity of the CP gene of eight ASPV isolates ranged from 77.0 to 97.0%, while the amino acid sequence identity ranged from 87.7 to 98.5%. The N-terminal region of the viral CP gene was highly variable, whereas the C-terminal region was conserved. Genetic algorithm recombination detection (GARD) and single breakpoint recombination (SBP) analyses identified base substitutions between eight ASPV isolates at positions 54 and 57 and position 771, respectively. GABranch analysis was used to determine whether the eight isolates evolved due to positive selection. All values in the GABranch analysis showed a ratio of substitution rates at non-synonymous and synonymous sites (dNS/dS) below 1, suggestive of strong negative selection forces during ASPV CP history. Although negative selection dominated CP evolution in the eight ASPV isolates, SLAC and FEL tests identified four possible positive selection sites at codons 10, 22, 102, and 158. This is the first study of the ASPV genome in Korea.

Cooperation Models and Cooperative Routing for Exploiting Hop-by-Hop Cooperative Diver sity in Ad Hoc Networks

  • Shin, Hee-Wook;Moh, Sang-Man;Chung, Il-Yong
    • Journal of Korea Multimedia Society
    • /
    • v.14 no.12
    • /
    • pp.1559-1571
    • /
    • 2011
  • In wireless ad hoc networks, nodes communicate with each other using multihop routed transmission in which hop-by-hop cooperative diversity can be effectively employed. This paper proposes (i) two cooperation models for per-link cooperation (PLC) and per-node cooperation (PNC) for exploiting cooperative diversity in wireless ad hoc networks and (ii) a cooperative routing algorithm for the above models in which best relays are selected for cooperative transmission. First, two cooperation models for PLC and PNC are introduced and represented as an edge-weighted graph with effective link quality. Then, the proposed models are transformed into a simplified graph and a cooperative routing algorithm with O(n2) time is developed, where n is the number of nodes in the network. The effectiveness of the algorithm is confirmed for the two cooperation models using simulation.