• Title/Summary/Keyword: diversity analysis

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Board Gender Diversity and Corporate Sustainability Performance: Mediating Role of Enterprise Risk Management

  • FAKIR, A.N.M. Asaduzzaman;JUSOH, Ruzita
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.6
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    • pp.351-363
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    • 2020
  • The objective of this paper is to explore how board gender diversity affects corporate sustainability performance. Therefore, this paper examines the direct association between board gender diversity with corporate sustainability performance and the mediation effect of enterprise risk management (ERM) on this association. The study employed a cross-sectional survey method. Data were collected from annual reports, websites, and through the questionnaires that were distributed to Chief Financial Officers (CFOs) of all the listed companies of Dhaka Stock Exchange, Bangladesh. The partial least square technique of Structural Equation Modelling (SEM) approach was employed for data analysis. The result did not find support for the direct association between board gender diversity and sustainability performance in Bangladesh context. This implies that contextual factors, such as, male-dominant board, appointment of female directors based on family ties, lack of education and expertise etc. may discount gender diversity direct influence on sustainability performance. However, the study finds strong support for the mediating role of ERM use within the corporate structure. Further analysis of indirect effect suggests that ERM use mediates the relationship of board gender diversity and sustainability performance in full. This implies that in the Bangladesh context effective use of ERM is highly recommended.

Comparative Analysis of the Korean Population of Magnaporthe oryzae by Multilocus Microsatellite Typing

  • Choi, Jaehyuk;Kim, Hyojung;Lee, Yong-Hwan
    • The Plant Pathology Journal
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    • v.29 no.4
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    • pp.435-439
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    • 2013
  • Rice blast fungus, Magnaporthe oryzae, inflicts serious damage to global rice production. Due to high variability of this fungal pathogen, resistance of newly-released rice cultivars is easily broken down. To understand the population structure of M. oryzae, we analyzed the genetic diversity of the Korean population using multilocus microsatellite typing. Eleven microsatellite markers were applied to the population of 190 rice isolates which had been collected in Korea for two decades since the 1980's. Average values of gene diversity and allele frequency were 0.412 and 6.5, respectively. Comparative analysis of the digitized allele information revealed that the Korean population exhibited a similar level of allele diversity to the integrated diversity of the world populations, suggesting a particularly high diversity of the Korean population. Therefore, these microsatellite markers and the comprehensive collection of field isolates will be useful genetic resources to identify the genetic diversity of M. oryzae population.

Effects of habitat differences on the genetic diversity of Persicaria thunbergii

  • Nam, Bo Eun;Nam, Jong Min;Kim, Jae Geun
    • Journal of Ecology and Environment
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    • v.40 no.2
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    • pp.84-88
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    • 2016
  • To understand the effects of habitat characteristics on the genetic diversity of Persicaria thunbergii, three sites of different environmental conditions in a water system were surveyed. Site A was the closest to the source of the water system, and there was a dam between sites A and B. Site C is located on the lowest downstream in the water system. Vegetation survey of four quadrats at each site was performed, and soil samples were collected for physicochemical analysis. Random amplification of polymorphic DNA (RAPD) analysis of ten P. thunbergii individuals at each site was conducted to calculate population genetic diversity and genetic distance among populations. Soil was sterile sand at site A, whereas loamy soil at sites B and C. A pure stand of P. thunbergii appeared at site A, while other species occurred together (such as Humulus japonicus and Phragmites australis) at sites B (Shannon-Wiener index; $H_B=0.309$) and C ($H_C=0.299$). Similar to the species diversity, genetic diversity (Nei's gene diversity; h) within population of site A ($h_A=0.2381$) was relatively lower than sites B ($h_B=0.2761$) and C ($h_C=0.2618$). However, site C was separated from sites A and B in genetic distance rather than the geographical distance (Nei's genetic distance; A~B, 0.0338; B~C, 0.0685; A~C, 0.0833).

Outage Probability Analysis of Multiuser MISO Systems Exploiting Joint Spatial Diversity and Multiuser Diversity with Outdated Feedback

  • Diao, Chunjuan;Xu, Wei;Chen, Ming;Wu, Bingyang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.9
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    • pp.1573-1595
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    • 2011
  • In this paper, the outage performance of multiuser multiple-input single-output (MISO) systems exploiting joint spatial and multiuser diversities is investigated for Rayleigh fading channels with outdated feedback. First, we derive closed-form exact outage probabilities for the joint diversity schemes that combine user scheduling with different spatial diversity techniques, including: 1) transmit maximum-ratio combining (TMRC); 2) transmit antenna selection (TAS); and 3) orthogonal space-time block coding (OSTBC). Then the asymptotic outage probabilities are analyzed to gain more insights into the effect of feedback delay. It is observed that with outdated feedback, the asymptotic diversity order of the multiuser OSTBC (M-OSTBC) scheme is equal to the number of transmit antennas at the base station, while that of the multiuser TMRC (M-TMRC) and the multiuser TAS (M-TAS) schemes reduce to one. Further by comparing the asymptotic outage probabilities, it is found that the M-TMRC scheme outperforms the M-TAS scheme, and the M-OSTBC scheme can perform best in the outage regime of practical interest when the feedback delay is large. Theoretical analysis is verified by simulation results.

Phylogenetic Analysis and Diversity of Marine Bacteria Isolated from Rhizosphere Soils of Halophyte in Suncheon Bay (순천만에 자생하는 염생식물 근권에서 유래한 해양세균의 계통학적 분석 및 다양성)

  • You, Young-Hyun;Park, Jong Myong;Lee, Myung-Chul;Kim, Jong-Guk
    • Microbiology and Biotechnology Letters
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    • v.43 no.1
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    • pp.65-78
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    • 2015
  • The bacterial diversity of the rhizosphere soil of S. japonica native to Suncheon bay was analyzed. Ninety two strains showing different morphological characteristics were isolated from the soils around the community of S. japonica. Bacterial diversity and distributions were studied by phylogenetic analysis of the partial 16S rDNA sequences. Ninety two strains were partially sequenced and analyzed phylogenetically. These strains were composed of 5 phyla firmicutes (56.5%), gamma-proteobacteria (29.3%), alpha-proteobacteria (5.4%), actinobacteria (5.4%), bacteroidetes (3.3%) and Shannon’s diversity index (H') were different from each of sampling sites (1.675, 1.924 and 2.04). Eleven isolates were presumed to be novel species candidates based on similarity analysis of the 16s rRNA gene sequences. Overall, Firmicutes and gamma-proteobacteria of the rhizosphere soil of S. japonica showed a high diversity.

Asymptotic Performance Analysis of Free-Space Optical Links with Transmit Diversity

  • Feng, Jianfeng;Zhao, Xiaohui
    • Journal of the Optical Society of Korea
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    • v.20 no.4
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    • pp.451-463
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    • 2016
  • The misalignment errors and fluctuations in irradiance due to atmospheric turbulence can severely degrade the performance of free-space optical (FSO) systems. In this paper, we investigate the asymptotic bit error rate (BER) performance and diversity orders of FSO links using parallel transmit-diversity schemes. The BER expressions of FSO links with the switch-and-examine transmit (SET), switch-and-examine transmit with post-selection (SETps), dual-branch transmit laser selection (Dual-TLS), and group transmit laser selection (Group-TLS) schemes are derived, based on an approximate channel model. Then numerical simulations for these four schemes in the region of high average signal-to-noise ratio (SNR) are presented under different channel conditions. The results show that the four transmit-diversity schemes can reduce system complexity and overcome the limitation of peak power, without much BER deterioration.

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

  • Ahn, Joengho;Lim, Jeeyoung
    • Journal of Engineering Education Research
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    • v.18 no.6
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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.

Performance Analysis of LR-aided ZF Receiver for MIMO Systems

  • Kim, Sangchoon
    • International journal of advanced smart convergence
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    • v.7 no.3
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    • pp.37-43
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    • 2018
  • Lattice-reduction (LR) techniques have been developed for signal detection in spatial multiplexing multiple input multiple output (MIMO) systems to obtain the largest diversity gain. Thus, an LR-assisted zero-forcing (ZF) receiver can achieve the maximum diversity gain in spatial multiplexing MIMO systems. In this paper, a simplified analysis of the achievable diversity gain is presented by fitting the channel coefficients lattice-reduced by a complex Lenstra-Lenstra-$Lov{\acute{a}}z$ (LLL) algorithm into approximated Gaussian random variables. It will be shown that the maximum diversity gain corresponding to two times the number of receive antennas can be achieved by the LR-based ZF detector. In addition, the approximated bit error rate (BER) expression is also derived. Finally, the analytical BER performance is comparatively studied with the simulated results.

Bacterial Community and Diversity from the Watermelon Cultivated Soils through Next Generation Sequencing Approach

  • Adhikari, Mahesh;Kim, Sang Woo;Kim, Hyun Seung;Kim, Ki Young;Park, Hyo Bin;Kim, Ki Jung;Lee, Youn Su
    • The Plant Pathology Journal
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    • v.37 no.6
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    • pp.521-532
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    • 2021
  • Knowledge and better understanding of functions of the microbial community are pivotal for crop management. This study was conducted to study bacterial structures including Acidovorax species community structures and diversity from the watermelon cultivated soils in different regions of South Korea. In this study, soil samples were collected from watermelon cultivation areas from various places of South Korea and microbiome analysis was performed to analyze bacterial communities including Acidovorax species community. Next generation sequencing (NGS) was performed by extracting genomic DNA from 92 soil samples from 8 different provinces using a fast genomic DNA extraction kit. NGS data analysis results revealed that, total, 39,367 operational taxonomic unit (OTU), were obtained. NGS data results revealed that, most dominant phylum in all the soil samples was Proteobacteria (37.3%). In addition, most abundant genus was Acidobacterium (1.8%) in all the samples. In order to analyze species diversity among the collected soil samples, OTUs, community diversity, and Shannon index were measured. Shannon (9.297) and inverse Simpson (0.996) were found to have the highest diversity scores in the greenhouse soil sample of Gyeonggi-do province (GG4). Results from NGS sequencing suggest that, most of the soil samples consists of similar trend of bacterial community and diversity. Environmental factors play a key role in shaping the bacterial community and diversity. In order to address this statement, further correlation analysis between soil physical and chemical parameters with dominant bacterial community will be carried out to observe their interactions.

SER Analysis of QAM with Space Diversity in Rayleigh Fading Channels

  • Kim, Chang-Joo;Kim, Young-Su;Jeong, Goo-Young;Mun, Jae-Kyung;Lee, Hyuck-Jae
    • ETRI Journal
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    • v.17 no.4
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    • pp.25-35
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    • 1996
  • This paper derives the symbol error probability for quadrature amplitude modulation(QAM) with L-fold space diversity in Rayleigh fading channels. Two combining techniques, maximal ratio combining(MRC) and selection combining(SC), are considered. The formula for MRC space diversity is obtained by averaging the symbol error probability of M-ary QAM in an additive white Gaussian noise(AWGN) channel over a chi-square distribution with 2L degrees of freedom. The obtained formula overcomes the limitations of the earlier work, which has been limited only to deriving the symbol error rate(SER) of QAM with two branch MRC space diversity. The formula for SC space diversity is obtained by averaging the symbol error probability of M-ary QAM in an AWGN channel over the distribution of the maximum signal-to noise ratio among all of the diversity channels for SC space diversity has been reported yet. Analytical results show that the probability of error decreases with the order of diversity gain per additional branch decreases as the number of branches becomes larger. On the other hand, the performance of 16 QAM with MRC becomes much better than that of SC as the number of branches becomes larger. By giving the order of diversity, L, and the number of signal points, M, we have been able to obtain the SER performance of QAM with general space diversity. These results can be used to determine the order of diversity to achieve the desired SER in land mobile communication system employing QAM modulation.

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