• Journal of Energy Engineering
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• v.23 no.2
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• pp.93-101
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• 2014

How to determine the extent of national energy security? In this paper, we estimate it by comparative analysis of South Korea and other OECD countries in terms of energy diversity (fuel diversity). Energy security consists of 4 key factors such as availability, accessibility, acceptability, affordability. Especially the importance of accessibility can grow as local imbalance of supply and demand increases. As a proxy of the accessibility, fuel diversity can be a significant indicator to estimate a measure of energy security. In this paper, we use Shannon-Wiener index to measure energy diversity. If fuel diversity increases, the stability of energy security also should increase, because of the smoothing effect to lessen dependence on key energy sources. In 2012 Korean growth rate of H-index (energy diversity) is 18.38%, which is higher than other OECD countries. However, Korean H-index itself is 1.93, lesser than other countries. Shift from oil to coals/gas within fossil fuels has more impact on H-index than weight transition from fossil fuels to renewable energies in Korea. We conclude that more renewable energy is an effective solution to achieve higher energy diversity and ultimately higher energy security as the same as the German case.

• Journal of Nutrition and Health
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• v.23 no.5
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• pp.309-316
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• 1990

The relationship between diet diversity and nutrient intake was studied. Diet diversity, caloric intake and dietary nutrient density values were examined as contributors to the level of selected nutrients with the use of data obtained from 14-day dietary records of 60 college women. The subjects were grouped into quartiles on the basis of level of intake of each of the specific nutrients. The indexes of diet diversity were the number of different food items and Shannon & Weaver's diversity index. Differences in diet diversity were found among nutrients and indexes. In general, calorie and protein intake were more diverse, on the other hand, intake of vitamins A and C were less diverse. With the exception of calcium, iron, vitamin $B_1$, niacin and vitamin C, the number of food items increased at each quartile of intake of specific nutrients. It was concluded that for some nutrients(as with fat), the number of food items consumed may be useful in estimating nutrient intakes. For other nutrients(as with calcium), utilization of nutrient-specific diversity indexes is necessary. Increased nutrient intake was accompanied by increased caloric intake(except vitamins A and C) and dietary nutrient density for all nutrients.

• Journal of Korean Society on Water Environment
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• v.35 no.6
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• pp.539-549
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• 2019

In 2016, Benthic Macroinvertebrates Streambed Index (BMSI) was proposed as an index to evaluate streams as benthic macroinvertebrate depending on the substrate type of streambed. However, orignal BMSI were selected without consideration of water quality. Analyzes without water quality do not constitute biological indices based solely on the substrate type of streambed. Therefore, in this study, the indicator value was improvement in consideration of water quality, and the distribution characteristics of benthic macroinvertebrates according to the substrate type of streambed were analyzed under relatively equal water quality conditions. We surveyed 20,155 sampling units in Korea from 2008 to 2018, and we re-estimated each lithophility of 191 taxa. As a result of estimating the streambed of each newly lithophilic value classification group considering the water quality, it was different from the original lithophilic value. Representative integer lithophilic values were newly calculated from 126 taxa among the 191 index taxa used in the analysis. The correlation between new constructed BMSI and community structure was compared and analyzed. It showed extreamely significance (p<0.001) in the dominance index, diversity index, abundance index, and evenness index of the community structure. Diversity index, abundance index, and evenness index showed positive correlation, and dominance index showed negative correlation. The correlation coefficient (r) was the highest in the richness index of about 0.664.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.7A
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• pp.477-484
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• 2003

In this paper, we compared and analyzed the influence of the fading index and the number of branch of diversity in the Nakagami-m fading channel environment when the MRC diversity and the hybrid SC/MRC are applied to the DS/CDMA system. We considered that the number of branches were 2,3, and 4, respectively and applied an individual diversity type according to the number of branches, when nakagami fading index(m) were 1 and 2. We found that when the Nakagami fading index m is small, that is to say, when fading is inferior, the application of a hybrid SC/MRC diversity Rake receiver is efficient; however, when the fading environment is good, the application of the MRC diversity Rake receiver is efficient. As a result, we verified that when the actual communication environment is inferior, the hybrid SC/MRC diversity that selects a strong signal to be received on an individual number of branches could replace the MRC diversity, as a method to achieve a similar performance by reducing the complexity of the system.

• Korean Journal of Environment and Ecology
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• v.35 no.3
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• pp.294-304
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• 2021

This study aims to obtain basic data for systematic restoration by analyzing the monitoring results of the Shimwon Valley Ecological Landscape Restoration Project area in Jirisan National Park. In 2017, when the restoration project was completed, 12 monitoring plots and 4 control plots were installed for vegetation monitoring, and changes in the relative dominance, species diversity index and similarity between 2017 and 2020 were analyzed. The species diversity index of the surveyed areas where trees were planted during the restoration project was 0-1.4552, and the similarity index with the control group was 0% except for one survey area at 1.32%. The very low species diversity index and similarity index in the survey areas were attributed to the loss of trees planted during the restoration project due to death, damage by wild boars, or erosion by running water. On the other hand, the species diversity index was 0.9538-2.3222 in the monitoring plot where no tree was planted, and the similarity index was analyzed to be as high as 8.33%. It is necessary to continue the long-term monitoring for the development of ecological landscape restoration methods in the national park and analysis of the succession in monitoring plots where no trees were planted.

• Journal of Environmental Impact Assessment
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• v.20 no.6
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• pp.845-856
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• 2011

In order to establish fundamental data for stream restoration and environmental flow, we investigated inhabitation and species diversity of fish to substrate size in the typical streams of Geum River Basin. Field monitoring including fish sampling was conducted from October 2007 to October 2009. Substrate size was determined according to six different : silt (Si), sand (Sa), fine gravel (Fg), coarse gravel (Cg), cobbles (Co) and boulders (Bo). A total number of fish caught in the 18 sites was 7,649 representing 10 families 50 species, and Si, Sa, Fg, Cg, Co and Bo stations occupied 30, 29, 38, 30, 27 and 17 species, respectively. The most frequently found species in number was pale chum (Zacco platypus, 29.7%, n=2,275) followed by Z. koreanus (22.5%, n=1,720) in total stations. Biological diversity with increase of substrate size from the dominance of part species showed higher values as dominance index, lower and diversity, richness and evenness index. Index of biological integrity (IBI) and qualitative habitat evaluation index (QHEI) scores decreased with increase of substrate size. Therefore, it is necessary to make an effort on stream rehabilitation with evaluation of physical habitat condition by indicator species in order to maintain biodiversity and perform ecological restoration.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.4
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• pp.420-425
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• 2003

Species composition, community structure and biodiversity of marine benthic community were studied in the intertidal zone of Seoam, Busan. A total of 75 species of benthic marine plants including 4 Cyanophyta, 6 Chlorophyta, 17 Phaeophyta, 47 Rhodophyta and 1 Magnoliophyta are listed. The dominant marine plants were melobesioidean algae, Chondracanthus tenellus, Sargasium thunbergii, Corallina spp., and Phyllospadix japonica and Ulva pertusa was added in summer. Chthamalus challengeri and Mytilus edulis were dominant zoobenthic species in the upper and middle intertidal zone. The algal species diversity index based on coverage was 1.81; 2.25 from frequency; 2.19 from average of total frequency and coverage, and 1.80 from importance value. The algal diversity indices estimated from different sources were quite different. This means that the index value changes depending on the sources used to calculate the species diversity index, indicating how important it is to select the based data and that it is necessary to standardize the methodology when studying later the algal diversity index. On the other hand, the number of species identified in this study has been found to be reduced by 65% at highest, compared with the result of the investigation that was conducted in the coast of Busan.

• Ocean Science Journal
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• v.40 no.1
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• pp.1-10
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• 2005

Variations in species diversity and abundance of polychaete taxocenes that occurred in 1980-1989 under different contamination levels of bottom sediments were studied in three areas of Peter the Great Bay. The most polluted area was shown to be the Golden Horn Inlet where contaminant contents in the bottom sediments exceed the threshold values of negative biota alterations. Amursky Bay is characterized by a moderate level of contamination, while Ussuriysky Bay has the lowest level of contamination. Pollutant contents vary considerably within the same areas and their separate patches are polluted differently. An integral index characterizing the contamination of bottom sediments is proposed. This index is an average grade of the rank value of contaminant contents in sediments. The index was used to compare the contamination level and data on polychaete species diversity and abundance. The highest species diversity of polychaetes is found in the least affected zones. Monotonous decrease of the species number, as well as decrease in the indices of diversity and evenness, is correlated with pollution level increases. Significant growth of the average polychaete biomass and polychaete density is observed in the case of an increase of contamination from low to moderate levels. Conversely, the biomass and abundance of polychaetes decline following an increase in contamination.

• The Plant Pathology Journal
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• v.22 no.1
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• pp.28-35
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• 2006

Virulence and genetic diversity were studied using 21 isolates of Sclerospora graminicola, the pearl millet downy mildew pathogen collected from major pearl millet growing areas of India. Variability for virulence was determined by inoculating a set of 10 differential hosts with the S. graminicola isolates in a greenhouse. The isolates varied for latent period (6.4 to 11 days), disease incidence (0 to $98\%$), virulence index (0 to 18.7) and oospore-production potential (1 to 4). Among the 21 isolates, Sg 139 (Rajasthan) was the most virulent and Sg 110 (Tamil Nadu) the least virulent. Based on virulence index (disease incidence$\time$slatent $period^{-1}$), the 21 isolates were classified into eight virulence groups. Genetic diversity among isolates was studied using AFLP markers. Based on similarity index of banding pattern, the 21 isolates were clustered into eight genotypic groups. The AFLP groupings, however, did not match with that of the virulence groupings, and these two were found independent. The isolate Sg 139 that remained distinct in both pathogenic and genetic groupings indicated its highly virulent nature. Implications of these results in downy mildew resistance breeding are discussed.

• Journal of Integrative Natural Science
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• v.15 no.3
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• pp.111-122
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• 2022

The purpose of this study was to investigate the ecological impact of wetlands by changing the species diversity of benthic macroinvertebrates and birds following the creation of an artificial wetland with a size of 30 m*30 m on bare land in reclaimed land in Haenam-gun, Korea. We investigated monthly fauna of benthic macroinvertebrates and birds in and outside wetlands and physicochemical indicators for 7 months from March to September 2014. During the study period, the water temperature and dissolved oxygen levels were consistently higher in wetlands than lakes. Many species of benthic macroinvertebrates were observed in summer (16 species in July) due to seasonal effects, and the species diversity index was highest in July and then gradually decreased. Thirteen species of birds were observed in March, 6 species in April, 5 species in July, and 1 species in June, where most winter birds and migratory birds were observed around wetlands in spring. The species diversity index also decreased after being high in July except for spring. This suggests that the abiotic environment in the wetland can be improved by creating an artificial wetland in the reclaimed land, and the increase in benthic macroinvertebrates can ultimately be a basic direction to restore the wetland ecosystem in the reclaimed land.