• Journal of Environmental Science International
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• v.19 no.4
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• pp.491-507
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• 2010

This study focuses on the fauna, seasonal prevalence and altitudinal distribution of the flies from March to November, 2008 in Mt. Hallasan, Jejudo Island, Korea. The fauna of flies was 39 species belonging to 5 Families which consist of 12 Calliphoridae, 19 Muscidae, 5 Sarcophagidae, 1 Dryomyzidae 1, Scathophagidae and 1 Anthomyiidae. The total number of flies collected was 21,605 with sex ratio of 57.98% in Mt. Halla. The ratio is higher than that of the residential area and other mountain survey sites. The average number of per trap individuals collected on the trapping day is 267, which is similar with the average of Mts. Jiryong, Juwang, Palgong and Gumo. The five dominant species showed a distinctive seasonal prevalence of 92.6% of the total flies: Chrysomyia pinguis (34.2%), Calliphora lata (25.3%), Hydrotaea dentipes(23.1%), Fannia scalaris (5.1%), and Lucilia caesar (4.9%). The seasonal prevalence of the flies was from the beginning of March to the end of November, and the highest peak time of the whole flies, males and females were different respectively. In the similarity index of the flies collected in different altitude, that of between 1,000 meters and 1,500 meters was the highest among the indices of 500 meters and above 1,000 meters. The index at each altitude was above 80% because of the same area. The diversity index of fly species was between 0.00 and 0.88 through altitudinal traps monthly. The highest index in Trap 1 was 0.88 in October, in Trap 2, 0.82 in July and in Trap 3, 0.63 in July. The diversity above 1,000 meters was most various in July. The five dominant species of C. pinguis, C. lata, H dentipes, F. scalaris, and L. caesar showed distinctive seasonal prevalence, relative abundance and altitudinal distribution respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.251-260
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• 2007

A species composition and population structure of fish, collected 16 times by bottom otter trawl in the coast of Geumo Island, from February 2002 to November 2005, was investigated. The fish species caught by bottom otter trawl from year 2002 to 2005 was entirely 72 species, 41 classes, and 12 orders, and the number of appearance and biomass was 5,999 individuals and 287,902.1g, respectively, being of the Perciformes(31 species and 19 classes; 43.1% in total number of species appeared) as a dominant species. 638 individuals of Leiognathus nuchalis which was 10.6% in total fish were appeared and 465 individuals of Konosirus punctatus(7.8%), 449 individuals of Engraulis japonicus(7.8%). biomass of Sebastes schlegeli was 33,258.7g as a dominant species(11.6% in total fish appeared) and 18,821.1g of Liparis agassizii(6.5%), 16,708.0g of Konosirus punctatus(5.8%). The diversity index of species per months of the collected by a small otter trawl in coastal water of Geumodo from year 2002 to 2005 was 2.860-3.639 and the evenness index was 0.825-0.887 in case of dominance index was 0.224-0.268 against the evenness index. The similarity of community structure per yearly was very high because of the relative difference(0.006), which was the least in 2004 and 2005.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.4
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• pp.210-219
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• 2007

The benthic marine algal flora and community structure were examined at five sites of the Taean Peninsula, Korea, during July-August 2005. Ninety-six algal species were Identified, including 14 green, 21 brown, and 60 red algae, and 1 marine plant. The common species that occurred at the five sites were Sargassum thunbergii, Gelidium divaricatum, Caulacanthus okamurae, Gracilavia vermiculophylla, and Neorhodomela aculeata. Sthunbergii was the dominant species in terms of coverage and biomass at ail of the study sites. The average biomass varied from $23.72g/m^2$ in dry weight at Chaeseokpo to $66.43g/m^2$ at Padori. The species could be divided into six functional groups in terms of morphological characteristics: 41 coarsely branched forms, 25 filamentous forms, 16 sheet forms, 7 thick leathery forms, including the marine plant Phyllospadix iwatensis, 4 crustose forms, and 3 Jointed calcareous forms. The seaweed communities at the five study sites were unstable and the environmental conditions were bad or very bad. Among the five study sites, the ecological evaluation index (EEI) and diversity index (H') were maximal at Padori at 2.29 and 1.98, respectively. By contrast, the dominance index (DI) was minimal at Padori (0.55) and maximal at Baramarae (0.96). Therefore, we conclude that the rocky shore at Padori has the best environment among the five study sites, although the species richness and biomass of seaweeds have declined continuously over the last 10 years.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.655-671
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• 2016

The distribution characteristics of functional feeding groups and biological evaluation of water quality with benthic macroinvertebrates were investigated from 2013 to 2014 in the mountain streams of Jirisan National Park. Both quantitative and qualitative collection had been performed six times during study periods in twelve sites located at upstream, midstream and downstream of four valleys, Chilsungol, Baemsagol, Daesunggol and Piagol of freshwater ecosystem in Jirisan National Park. As results, the total collected benthic macroinvertebrates were 3 phyla, 4 classes, 11 orders, 37 families, 107 species and 4,028 individuals. In 2013, 3 phyla, 4 classes, 10 orders, 32 families, 89 species and 1,829 individuals were collected. And in 2014, 3 phyla, 4 classes, 9 orders, 31 families, 80 species and 2,199 individuals were identified. The total dominant species was Ecdyonurus kibumensis, and EPT groups occupied 80.39% of total species number. Biotic indices were also compared to site and to season. The dominant index (DI) was highest at the downstream of Baemsagol in the spring of 2013, and the evenness index (J') was highest at the downstream of Daesunggol in the summer of 2013. Both diversity index (H') and richness index (RI) were highest at the upstream of Baemsagol in the summer of 2014. The correlation between altitude above sea level and functional feeding groups of benthic macroinvertebrates was also researched in this study. As a result, the species number of shredders and predators have significantly increased according to the increase of the altitude of their habitat. On the other hand, individuals of gathering collectors have increased according to the increase of altitude. The biological water quality was evaluated and compared with several methods in this study, and we suggest that ESB and GPI are more appropriate than KSI and BMI to evaluate biological water quality of mountain stream water.

• 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.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.1113-1119
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• 2021

This study aims to determine the impact of the news coverage of the COVID-19 pandemic on the composite stocks' movement (IHSG) in Indonesia. This study used secondary data of daily time series with an observation range of March 2020-June 2020. This study used three main variables, namely, COVID-19 news, the daily price of a composite stock market index (IHSG), and interest rate. This study clarifies pandemic news into two forms to facilitate quantitative analysis, namely, good news and bad news. Both pandemic news conditions, which have been clarified, are then processed into the index and reprocessed along with two other variables using vector autoregressive (VAR). The results showed that the good news have a dominant effect on developing the composite stock price index (IHSG) in Indonesia during the COVID-19 pandemic. Although the good news dominates the composite stock price index (IHSG) movement in Indonesia, the bad news must also be anticipated. By implementing a series of macroeconomic policies that follow the conditions of the composite stock price index (IHSG) movements on the stock exchange floor, the bad news response can decrease the potential for a decline in investor confidence, so that the financial system's macroeconomic stability is maintained.

• Korean Journal of Weed Science
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• v.4 no.1
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• pp.4-10
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• 1984

This experiment was conducted to determine the change in weed flora with season and cultivated crop and land. There are 44 species in 38 genera and 18 families, consisting of 22 annual, 11 biennial and 9 perennial weeds in uplands in Jeonbug Province. Digitaria sanguinalis Scopol. occurred with the highest frequency of 67.2% and in decreasing order Portulaca oleracea L., Chenopodium album L. and Erigeron canadensis L. followed. About 60% of total sites studied indicated Simpson`s index ranging from 0.20 to 0.50. The Simpson`s index decreased from 0.65 on June 8 to 0.15 on November 10. Dominant weed species were Alopecurus aequalis Sosbol, and Polygonum hydropiper Spach in double cropping paddy field, but D. sanguinalis and P. oleracea were the dominant species in uplands. In reclaimed uplands various weed species including, 4rtemisia asiatica Nakai occurred almost equally. Average Simpson`s index for six crops studied was 0.40 and irrespective of the crops being cultivated P. oleracea and D. sanguinalis were dominant weed species and Y. hydropiper, C. album, Exolus blitum Grenier and E. canadensis were sub-dominant.

• Korean Journal of Weed Science
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• v.8 no.1
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• pp.1-8
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• 1988

In order to get basic information for establishing weed control methods, weed distribution was surveyed at 15 days interval in garlic and red pepper fields at 8 locations in Chungnam Province. In garlic fields, 68 weed species(27 families) were distributed. Portulaca oleracea, Chenopodium album and Digitana sanguinalis were most dominant and Equisetum arvense, Alopecurus aequalis, and Setaria viridis dominant among them. Highest number of weeds emerged in May and dry weight or weeds was more heavy in June and summer broadleaf weeds were most abundant throughout garlic growing period. In red pepper fields, 38 weed species(17 families) were distributed, D. sanguinalis, Cyperus amuricus and P. oleracea were most dominant and Echinochloa crus-galli, Eleusine indica, D. violascens, and Centipeda minima also dominant among them. The highest number of weeds were emerged in June and summer, grasses and summer broadleaf weeds were more abundant in June and July. Seasonal Shannon's diversity index(H'), maximum diversity(Hmax') and eveness(J') for the Shannon diversity index, and Simpson index were high in both red pepper and garlic fields. Interspecific competition(probability for interspecific encounter) was more severe than intraspecific competiton.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.6
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• pp.1078-1086
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• 2009

This paper presents a Fourier based algorithm for estimating the parameters of the low frequency oscillating modes. The proposed methods estimates various parameters(frequency, damping factor, mode magnitude, phase) by fitting Fourier spectrum and phase with a damped exponential cosine function. Dominant frequency is selected by taking frequency corresponding to the peak spectrum, and damping factor is estimated using the left/right spectra of Fourier spectrum. In addition, mode magnitude is calculated by the normalized peak spectrum, and phase is estimated from spectrum phase. Also, we introduce an accuracy index in order to determine the accuracy of the estimated parameters, and the index is calculated using the deviations of the peak spectrum and the left/right spectra. The parameter estimation methods proposed in this paper include very simple arithmetical processes, so the algorithms are simple and the calculation speed is very fast. The proposed methods are applied to test functions with two dominant modes. The results show that the proposed methods are highly applicable to low frequency parameter estimation.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.7
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• pp.1038-1043
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• 2015

In this study, we investigated the effects of mixing on the aggressive behavior of commercially housed pigs. The behavioral patterns of 36 groups of pigs (a total of 360 animals) were observed over 3 consecutive days directly after weaning ($25{\pm}1.2$ days of age), and 25 and 50 days later with the aid of video technology. Fight latency and total duration and frequency of fighting were significantly different among the age groups. The aggressive behaviors decreased in 75-day old pigs if compared to 25- and 50-day old animals. Moreover, dominance index (DI) was higher in 25-day old and lower in 75-day old pigs. A comparison of dominant (DI>0) and submissive (DI<0) pigs showed significant differences (p<0.05) for major aggressive behaviors in all age groups. Dominant pigs were involved in more aggressive interactions, had longer fights, and initiated more fights than submissive pigs. Post-mixing aggressive behavior was altered by previous experience of mixing. Aggressive behavior and DI are suitable methods for analyzing the effects of mixing on commercially housed growing pigs.