• Title/Summary/Keyword: diversity methods

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Propose Diversity Algorithm for Mobile Communication System Performance Improve (이동통신 시스템 성능 향상을 위한 다이버시티 알고리즘제안)

  • Lee, Myung-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.11 no.5 s.43
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    • pp.203-209
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    • 2006
  • In this paper, proposed diversity algorithm that decrease fading. In the wireless channel, if fading occurs due to the multipaths the performance of the system is apparently reduced. This study applied tap-delay receiver. It applied QPSK and OQPSK modulation methods and applied the convolutional codes, where the code rate is 1/2 and 1/3 and the constraint length is 11 and the turbo code where the constraint length is 6. The diversity algorithm proposed in this paper could be compared and analyzed the average error probability of modulation method variable of fading factor to uplink and downlink channels.

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Equal Gain Block Decomposition Methods for Multiuser MIMO Networks

  • Hwang, Insoo;Kang, Inseok;Hwang, Intae;You, Cheolwoo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.3
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    • pp.1156-1173
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    • 2021
  • In this paper, we propose a new joint precoder and postcoder design strategy to support multiple streams per user in multiuser multiple-input multiple-output (MIMO) systems. We propose two step precoding strategies using equal channel gain decomposition and block diagonalization at the transmitter. With the proposed precoder, the multiuser MIMO channel can be decomposed into multiple parallel channels with equal channel gain per user. After applying receive postcoder which is generated and sent by the transmitter, we can use ML based decoder per stream to achieve full receive diversity. Achievable sum rate bound and diversity performance of the proposed algorithm are presented with feedback signaling design and quantitative complexity analysis. Simulation results show that the proposed algorithm asymptotically approaches to the sum rate capacity of the MIMO broadcast channel while maintaining full diversity order.

Genetic diversity analysis in Chinese miniature pigs using swine leukocyte antigen complex microsatellites

  • Wu, Jinhua;Liu, Ronghui;Li, Hua;Yu, Hui;Yang, Yalan
    • Animal Bioscience
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    • v.34 no.11
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    • pp.1757-1765
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    • 2021
  • Objective: The swine leukocyte antigen (SLA) gene group, which is closely linked and highly polymorphic, has important biomedical significance in the protection and utilization of germplasm resources. However, genetic polymorphism analyses of SLA microsatellite markers in Chinese miniature pigs are limited. Methods: Eighteen pairs of microsatellite primers were used to amplify the SLA regions of seven miniature pig breeds and three wild boar breeds (n = 346) from different regions of China. The indexes of genetic polymorphism, including expected heterozygosity (He), polymorphic information content (PIC), and haplotype, were analyzed. The genetic differentiation coefficient (Fst) and neighbor-joining methods were used for cluster analysis of the breeds. Results: In miniature pigs, the SLA I region had the highest numbers of polymorphisms, followed by the SLA II and SLA III regions; the region near the centromere had the lowest number of polymorphisms. Among the seven miniature pig breeds, Diannan small-ear pigs had the highest genetic diversity (PIC value = 0.6396), whereas the genetic diversity of the Hebao pig was the lowest (PIC value = 0.4330). The Fst values in the Mingguang small-ear, Diannan small-ear, and Yunnan wild boars were less than 0.05. According to phylogenetic cluster analysis, the South-China-type miniature pigs clustered into one group, among which Mingguang small-ear pigs clustered with Diannan small-ear pigs. Haplotype analysis revealed that the SLA I, II, and III regions could be constructed into 13, 7, and 11 common haplotypes, respectively. Conclusion: This study validates the high genetic diversity of the Chinese miniature pig. Mingguang small-ear pigs have close kinship with Diannan small-ear pigs, implying that they may have similar genetic backgrounds and originate from the same population. This study also provides a foundation for genetic breeding, genetic resource protection, and classification of Chinese miniature pigs.

A double-labeling marker-based method for estimating inbreeding and parental genomic components in a population under conservation

  • Li, Wenting;Zhang, Mengmeng;Wang, Kejun;Lu, Yunfeng;Tang, Hui;Wu, Keliang
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.1
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    • pp.12-23
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    • 2020
  • Objective: The objective of a conservation program is to maintain maximum genetic diversity and preserve the viability of a breed. However, the efficiency of a program is influenced by the ability to accurately measure and predict genetic diversity. Methods: To examine this question, we conducted a simulation in which common measures (i.e. heterozygosity) and novel measures (identity-by-descent probabilities and parental genomic components) were used to estimate genetic diversity within a conserved population using double-labeled single nucleotide polymorphism markers. Results: The results showed that the accuracy and sensitivity of identity-by-state probabilities and heterozygosity were close to identity by descent (IBD) probabilities, which reflect the true genetic diversity. Expected heterozygosity most closely aligned with IBD. All common measures suggested that practices used in the current Chinese pig conservation program result in a ~5% loss in genetic diversity every 10 generations. Parental genomic components were also analyzed to monitor real-time changes in genomic components for each male and female ancestor. The analysis showed that ~7.5% of male families and ~30% of female families were lost every 5 generations. After 50 generations of simulated conservation, 4 male families lost ~50% of their initial genomic components, and the genomic components for 24.8% of the female families were lost entirely. Conclusion: In summary, compared with the true genetic diversity value obtained using double-labeled markers, expected heterozygosity appears to be the optimal indicator. Parental genomic components analysis provides a more detailed picture of genetic diversity and can be used to guide conservation management practices.

Comparison of Occurrences of Coleoptera by Three Sampling Methods in Mt. Yeonyeop Area, Korea (채집법에 따른 연엽산 일대 딱정벌레목의 출현상 비교 분석)

  • Jeong Jong-Kook;Lee Seung-Il;Choi Jae-Seok;Kwon Oh-Kil
    • Korean Journal of Environmental Biology
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    • v.23 no.3 s.59
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    • pp.228-237
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    • 2005
  • To compare the occurrence of Coleoptera by different sampling methods such as light trap, pitfall trap and sweeping, we collected samples every month from April to September,2004 in the Mt. Yeonyeop, Gangwon-do, Korea. According to the sampling methods, the species composition, abundance and dry weight were completely different. We collected 151 species in 35 families (690 individuals) by sweeping method, 148 species in 30 families (689 individuals) by light trap, and 112 species in 18 families (1,674 individuals) by pitfall trap, respectively. The dry weight in collected sample was about 181.46 g in pitfall trap,39.85 g in light trap, and 10.89 g in sweeping method, respectively. Relatively high flight and small-sized beetles such as Coccinellidae, Nitidulidae, Scarabaeidae were collected in light trap. The species diversity was high in July. Unlike the samples collected in light trap, the pitfall trap samples were big-sized saprophagous or carnivorous beetles such as Carabidae, Silphidae, Staphylinidae. The pitfall trap showed relatively the higher number of individual and lower species diversity compared to other methods. The major samples collected by sweeping method were small-sized carnivorous or herbivorous beetles such as Chrysomelidae, Curculionidae, Coccinellidae. The peak of species diversity occurred in May. The similarity was calculated with the Jaccard's index over the light trap-pitfall trap was 0.07, light trap-sweeping was 0.10, and pitfall trap-sweeping was 0.01. Consequently, similarity of sampling methods was relatively low. In conclusion, efficiency of the each sampling methods significantly differed in the species composition of Coleoptera. This study emphasize the necessity of using three sampling methods in the area of diversity research.

Diversity, distribution, and antagonistic activities of rhizobacteria of Panax notoginseng

  • Fan, Ze-Yan;Miao, Cui-Ping;Qiao, Xin-Guo;Zheng, You-Kun;Chen, Hua-Hong;Chen, You-Wei;Xu, Li-Hua;Zhao, Li-Xing;Guan, Hui-Lin
    • Journal of Ginseng Research
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    • v.40 no.2
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    • pp.97-104
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    • 2016
  • Background: Rhizobacteria play an important role in plant defense and could be promising sources of biocontrol agents. This study aimed to screen antagonistic bacteria and develop a biocontrol system for root rot complex of Panax notoginseng. Methods: Pure-culture methods were used to isolate bacteria from the rhizosphere soil of notoginseng plants. The identification of isolates was based on the analysis of 16S ribosomal RNA (rRNA) sequences. Results: A total of 279 bacteria were obtained from rhizosphere soils of healthy and root-rot notoginseng plants, and uncultivated soil. Among all the isolates, 88 showed antagonistic activity to at least one of three phytopathogenic fungi, Fusarium oxysporum, Fusarium solani, and Phoma herbarum mainly causing root rot disease of P. notoginseng. Based on the 16S rRNA sequencing, the antagonistic bacteria were characterized into four clusters, Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetesi. The genus Bacillus was the most frequently isolated, and Bacillus siamensis (Hs02), Bacillus atrophaeus (Hs09) showed strong antagonistic activity to the three pathogens. The distribution pattern differed in soil types, genera Achromobacter, Acidovorax, Brevibacterium, Brevundimonas, Flavimonas, and Streptomyces were only found in rhizosphere of healthy plants, while Delftia, Leclercia, Brevibacillus, Microbacterium, Pantoea, Rhizobium, and Stenotrophomonas only exist in soil of diseased plant, and Acinetobacter only exist in uncultivated soil. Conclusion: The results suggest that diverse bacteria exist in the P. notoginseng rhizosphere soil, with differences in community in the same field, and antagonistic isolates may be good potential biological control agent for the notoginseng root-rot diseases caused by F. oxysporum, Fusarium solani, and Panax herbarum.

Comparative Performance Analysis of Transmit Diversity Technique for WCDMA Systems (WCDMA 시스템에서 송신 다이버시티 기법의 성능 비교 분석)

  • Lee, Sang-Ho;Kim, Young-Sun;Park, Hyung-Rae
    • Journal of Advanced Navigation Technology
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    • v.7 no.2
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    • pp.191-198
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    • 2003
  • In this paper, we analyze the performance of transmit diversity techniques which are the key technologies of the third generation mobile communication systems. Transmit diversity techniques adopted on the specification of 3GPP are classified into open-loop and closed-loop methods depending on the existence of feedback data. In WCDMA systems, the DPCH signal is space-time coded to provide a mobile station with diversity. Computer simulations shall be performed to analyze and compare their performance considering the effect of mobile speed, number of path, power control, and delay of feedback with the WCDMA slot format #13 for application to WCDMA systems.

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The Impact of Openness to Diversity on Creativity of Nursing College Students with a Focus on Mediating Effects (간호대학생의 다양성 수용도가 창의성에 미치는 영향: 매개효과를 중심으로)

  • Park, Ju Young;Woo, Chung Hee
    • The Journal of Korean Academic Society of Nursing Education
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    • v.23 no.3
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    • pp.241-251
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    • 2017
  • Purpose: The purpose of this study is to examine how the acceptance of diversity of nursing college students affects creativity and to verify empirically the role of individual cooperative learning competency and unlearning competency in such influence relations. Methods: This study surveyed 209 nursing college students and analyzed the structured questionnaire data using SPSS WIN 21.0 and AMOS 18.0. Results: The results of this study were as follows. First, the creativity of the subjects showed significant correlations with all other variables. Second, diversity openness directly affected creativity. We also confirmed that diversity openness and cooperative learning competency have a positive effect on creativity through mediating unlearning competency. Conclusion: In order to enhance the creativity of nursing college students, diversity openness should be actively reflected in the curriculum. In addition, concrete teaching-learning strategies should be developed in order to increase and enhance the unlearning competency and cooperative learning competency of nursing students.

Effect of Non-indigenous Bacterial Introductions on Rhizosphere Microbial Community

  • Nogrado, Kathyleen;Ha, Gwang-Su;Yang, Hee-Jong;Lee, Ji-Hoon
    • Korean Journal of Environmental Agriculture
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    • v.40 no.3
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    • pp.194-202
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    • 2021
  • BACKGROUND: Towards achievement of sustainable agriculture, using microbial inoculants may present promising alternatives without adverse environmental effects; however, there are challenging issues that should be addressed in terms of effectiveness and ecology. Viability and stability of the bacterial inoculants would be one of the major issues in effectiveness of microbial pesticide uses, and the changes within the indigenous microbial communities by the inoculants would be an important factor influencing soil ecology. Here we investigated the stability of the introduced bacterial strains in the soils planted with barley and its effect on the diversity shifts of the rhizosphere soil bacteria. METHODS AND RESULTS: Two different types of bacterial strains of Bacillus thuringiensis and Shewanella oneidensis MR-1 were inoculated to the soils planted with barley. To monitor the stability of the inoculated bacterial strains, genes specific to the strains (XRE and mtrA) were quantified by qPCR. In addition, bacterial community analyses were performed using v3-v4 regions of 16S rRNA gene sequences from the barley rhizosphere soils, which were analyzed using Illumina MiSeq system and Mothur. Alpha- and beta-diversity analyses indicated that the inoculated rhizosphere soils were grouped apart from the uninoculated soil, and plant growth also may have affected the soil bacterial diversity. CONCLUSION: Regardless of the survival of the introduced non-native microbes, non-indigenous bacteria may influence the soil microbial community and diversity.

Cloaking Method supporting K-anonymity and L-diversity for Privacy Protection in Location-Based Services (위치기반 서비스에서 개인 정보 보호를 위한 K-anonymity 및 L-diversity를 지원하는 Cloaking 기법)

  • Kim, Ji-Hee;Lee, Ah-Reum;Kim, Yong-Ki;Um, Jung-Ho;Chang, Jae-Woo
    • Journal of Korea Spatial Information System Society
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    • v.10 no.4
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    • pp.1-10
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    • 2008
  • In wireless internet, the location information of the user is one of the important resources for many applications. One of these applications is Location-Based Services (LBSs) which are being popular. Because, in the LBS system, users request a location-based query to LBS servers by sending their exact location, the location information of the users can be misused by adversaries. In this regard, there must be a mechanism which can deal with privacy protection of the users. In this paper, we propose a cloaking method considering both features of K-anonymity and L-diversity. Our cloaking method creates a minimum cloaking region by finding L number of buildings (L-diversity) and then finding number of users (K-anonymity). To support this, we use a R*-tree based index structure and use filtering methods especially for the m inimum cloaking region. Finally, we show from a performance analysis that our method outperforms the existing grid based cloaking method.

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