• ETRI Journal
• /
• 제43권3호
• /
• pp.400-413
• /
• 2021

This paper theoretically and empirically explores the reliability gain that can be obtained by installing multiple antennas in on-vehicle broadcasting receivers. Analytical derivations reveal that maximal-ratio-combining-based diversity allows a multi-antenna receiver (MR) to achieve significantly better coverage probability than a single-antenna receiver (SR). In particular, the notable MR gains for low-power reception and high-throughput services are highlighted. We also discuss various aspects of mobile MRs, including geometric coverage, volume of the users served, and impact of receiver velocity. To examine the feasibility of MRs in the real world, extensive field experiments were conducted, particularly with on-air ATSC 3.0 broadcast transmissions. Relying on the celebrated erroneous second ratio criterion, MRs with two and four antennas were verified to achieve notable reliability gains over SRs in practice. Furthermore, our results also prove that layered-division multiplexing can cope better with receiver mobility than traditional time-division multiplexing when multiple services are intended in the same radio frequency channel.

• Mycobiology
• /
• 제47권4호
• /
• pp.401-407
• /
• 2019

Two new species of the lichen genus Placolecis are discovered in China, namely P. kunmingensis An. C. Yin & Li S. Wang and P. sublaevis An. C. Yin & Li S. Wang. The new combination P. loekoesiana (S.Y. Kondr., Farkas, J.J. Woo & Hur) An. C. Yin is proposed. Placolecis kunmingensis is characterized by having simple, spherical or ellipsoid, hyaline spores, and pear-shaped pycnidia; while P. sublaevis can be distinguished by its thallus forming larger aggregations with slightly flattened lobes at the thallus margin, and urn-shaped pycnidia. Descriptions, a phylogenetic tree and a key are provided for all the known Placolecis species in China.

• Mycobiology
• /
• 제47권1호
• /
• pp.76-86
• /
• 2019

Scab disease caused by Venturia nashicola is of agroeconomic importance in cultivation of Asian pear. However, little is known about the degree of genetic diversity in the populations of this pathogen. In this study, we collected 55 isolates from pear scab lesions in 13 major cultivation areas in Korea and examined the diversity using sequences of internal transcribed spacer (ITS) region, ${\beta}$-tubulin (TUB2), and translation elongation factor-$1{\alpha}$ ($TEF-1{\alpha}$) genes as molecular markers. Despite a low level of overall sequence variation, we found three distinctive subgroups from phylogenetic analysis of combined ITS, TUB2, and $TEF-1{\alpha}$ sequences. Among the three subgroups, subgroup 1 (60% of isolates collected) was predominant compared to subgroup 2 (23.6%) or subgroup 3 (16.4%) and was distributed throughout Korea. To understand the genetic diversity among the subgroups, RAPD analysis was performed. The isolates yielded highly diverse amplicon patterns and none of the defined subgroups within the dendrogram were supported by bootstrap values greater than 30%. Moreover, there is no significant correlation between the geographical distribution and the subgroups defined by molecular phylogeny. Our data suggest a low level of genetic diversification among the populations of V. nashicola in Korea.

• ALGAE
• /
• 제36권1호
• /
• pp.13-24
• /
• 2021

The present-day genetic structure of macroalgal species reflects both geographical history and oceanic circulation patterns as well as anthropogenic introduction across native ranges. To precisely understand the genetic diversity and how the factors shape the current population structure of Gloiopeltis furcata sensu lato, we determined the mitochondrial 5' end of cytochrome c oxidase subunit I (COI-5P) sequences for 677 individuals sampled from 67 sites spanning almost the entire distribution range in Korea and Japan. Results from the phylogenetic analysis and haplotype distribution revealed eleven distinct lineages within G. furcata s.l. along the Korea-Japan coastal areas and displayed divergent phylogeographic patterns among lineages. Despite the closely related lineages distributed in same habitats as high rocky intertidal zone, they display different phylogeographic patterns among lineages. The populations from the south of Korea-Japan harbored the highest genetic diversity and unique endemism in comparison with other populations in the distribution range. This could be the evidence of southern refugia for G. furcata s.l. in the Northwest (NW) Pacific and the recent migration from native to introduced region. The reason is that an exceptional distribution pattern was found high genetic diversity in Hakodate of Japan where is the northern location in the NW Pacific. Our results imply the contemporary influence on the distribution due to current circulation pattern and anthropogenic effects. These phylogeographic findings provide the important insight into cryptic species diversity and the detailed distribution pattern of Gloiopeltis in the NW Pacific.

• ALGAE
• /
• 제37권2호
• /
• pp.135-147
• /
• 2022

The red algal genus Chondrus have long been used as raw materials for carrageenan and dietary fiber in health foods. Despite the importance of genetic information in safeguarding natural seaweed resources, knowledge of the population genetics of Chondrus in the northwest Pacific is limited. In this study, genetic diversity and phylogeographic structure of 45 populations (777 specimens) of Chondrus from Korea, China, and Japan were evaluated based on mitochondrial COI-5P gene sequences, and phylogenetic relationships were confirmed based on plastid rbcL gene sequences. Molecular analyses assigned the specimens in this study to three Chondrus species: C. nipponicus, C. ocellatus, and C. giganteus; phenotype-based species classification was impossible owing to their high morphological plasticity. We found moderate intraspecific genetic diversity and a shallow phylogeographic structure in both for C. nipponicus and C. ocellatus, and low intraspecific genetic diversity in C. giganteus. Each of the three species exhibited high-level intraspecific gene flow among regions based on the most common haplotypes (CN1 for C. nipponicus, CO1 for C. ocellatus, and CG1 for C. giganteus). Our comprehensive genetic information provides insights into the phylogeographic patterns and intraspecific diversity of the economically important Chondrus species. It also highlights the need to conserve existing natural Chondrus resources through continuous monitoring of genetic diversity and phylogeographic pattern.

• Journal of Plant Biotechnology
• /
• 제50권
• /
• pp.207-214
• /
• 2023

Lindera obtusiloba (Lauraceae) is a dioecious tree that is widely distributed in the low-altitude montane forests of East Asia, including Korea. Despite its various pharmacological properties and ornamental value, the genetic diversity and population structure of this species in Korea have not been explored. In this study, we selected 6 nuclear and 6 chloroplast microsatellite markers with polymorphism or clean cross-amplification and used these markers to perform genetic diversity and population structure analyses of L. obtusiloba samples collected from 20 geographical regions. Using these 12 markers, we identified a total of 44 alleles, ranging from 1 to 8 per locus, and the average observed and expected heterozygosity values were 0.11 and 0.44, respectively. The average polymorphism information content was 0.39. Genetic relationship and population structure analyses revealed that the natural L. obtusiloba population in Korea is composed of 2 clusters, possibly due to two different plastid genotypes. The same clustering patterns have also been observed in Lindera species in mainland China and Japan.

• 한국조경학회지
• /
• 제33권4호
• /
• pp.1-10
• /
• 2005

Recently, as urban landscape is growing in importance, urban landscape planning is being actively performed. for this purpose, classification of the urban landscape is definitely required. Therefore, this research focuses on classifying urban landscape in Daejeon metropolis by dividing the urban land use pattern. This results are as follows. 1. Urban land use pattern is divided into 20 classes. The residential, commercial and industrial areas, the old market and the bus terminal are evaluated negatively, whereas the areas of school, water reservoir, neighborhood park and train station are appreciated as being positive in landscape characters. 2. As a result of a cluster analysis, urban landscape has five different landscape types. These are: landscapes of medium diversity lacking green area, landscapes of high diversity lacking green area, landscapes rich in green area and with medium diversity, landscapes rich in green area and with high diversity, and landscapes rich in green area and with low diversity. 3. In landscape characters of beauty and harmony, landscapes rich in green area and with medium diversity are more positively evaluated than those rich in green area and with low diversity. This point should be taken into account for planning the urban landscape.

• 한국조리학회지
• /
• 제10권1호
• /
• pp.140-152
• /
• 2004

This study investigates and analyzes the diversity of menu in military meal services that are recognized by the soldiers who are familar with meal services, and suggests the implications on the results of the analysis. For the ranks of respondents in terms of demographic features, the sergeants and corporals were 43.2%(186) and 29.7%(128) apiece. It was identified that the diversity of menu and significant influences as 57.5%. Thus, it is necessary to diversity the menus more than the present menus to increase the satisfaction of new generation on military meal services. The most influential factor on the diversity of menu was the hard-boiled food as 29.9% among 15 items. Therefore, the first measure to intensify the satisfaction of soldiers on meal services is to diversity the hard-boiled food. Accordingly, this measure will contribute to relieve the most biggest complaints on the diversity of menu in military meal services. For this purpose, it is recommended to replace the kitchen work system consisted of kitchen polices with the non-officer system enabling the long-term service. The kitchen polices are transferred to the first reserve list when they are accustomed to their duties because the period of service is limited under the present kitchen police system. Therefore, the present kitchen police system has the problem that it can't overcome the limit in terms of the quality of meal service.

• Journal of Information Technology Applications and Management
• /
• 제18권1호
• /
• pp.101-123
• /
• 2011

Considering how an organization is timely competitive for survival in the rapidly changing environment of today, it is more important to get new information and knowledge continuously by teams. However team system provides organization with opportunities and, at the same time, is provoked into conflict by the diversity of team members. This study examines the effect of team diversity on knowledge creation and investigates the influence of absorptive capacity and conflict as mediators. The sample population consisted of officials who work in teams at two business corporations that have successfully achieved knowledge creation. The result presents team diversity serves as an effective factor for absorptive capacity and absorptive capacity also serves as an effective factor for knowledge creation. In contrast, team diversity brings team members into conflict and conflict has a negative effect on knowledge creation. Another significant finding of this research is the fact that a positive effect of absorptive capacity on knowledge creation is greater than a negative effect of conflict on it. It clearly demonstrates that team diversity can be an important determinant of knowledge creation if an organization tries to reduce team member's conflict.

• 동아시아경상학회지
• /
• 제10권1호
• /
• pp.123-136
• /
• 2022

Purpose - Diversity subject is rising globally, as the proportion of women in the workforce increased to a large extent and the variety of resources became greater. Diversity attempts have appealed more awareness to the value of female participation in various areas, notably in the boardroom and corporate governance. This study tests the relationships among gender diversity, openness, and innovation, at the firm level across countries from the MOI Survey. Research design, data, and methodology - In this study the relationships among gender diversity, openness, and innovation were investigated at the firm level across countries from the Management, Organisation, and Innovation (MOI) Survey. A cross-cultural analysis was conducted based on the empirical evidence from six countries: Germany, India, Lithuania, Poland, Romania, and Russia. Result - The results show that gender diversity is positively related to innovation performance, moreover openness is positively associated with the level of firm innovation. In addition, a company's capability to use knowledge from outside and the creation of new combinations positively influence a firm's potential to innovate. Conclusion - This study suggests that the more gender-diverse top management team and the higher openness may bring the firm's innovation with greater possibility. the paper encourages more female participation on top management on the grounds of recommending that firms with greater gender diverse top management teams.