• 한국환경과학회지
• /
• 제19권4호
• /
• pp.491-507
• /
• 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.

• 수산해양기술연구
• /
• 제43권4호
• /
• pp.251-260
• /
• 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.

• 한국수산과학회지
• /
• 제40권4호
• /
• pp.210-219
• /
• 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.

• 한국환경과학회지
• /
• 제25권5호
• /
• pp.655-671
• /
• 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.

• 한국해양학회지:바다
• /
• 제8권4호
• /
• pp.420-425
• /
• 2003

부산 서암 조간대 부착생물군집의 종조성, 군집구조, 종다양성을 조사하였다. 부착해산식물의 출현종수는 남조류 4종, 녹조류 6종, 갈조류 17종, 홍조류 47종, 해산종자식물 l종으로 총 75종이 관찰되었다. 부착해산식물 우점종은 melobesioidean algae, Chondracanthus tenellus, Sargassium thunbergii, Corallina spp., Phyllospadix japonica 5 종이었고, 여름에 Ulva pertusa가 추가되는 경향을 보였다. 저서동물은 Chthamalus challengeri and Mytilus edulis 가 조간대 상부와 중부에 우점하는 단순한 분포를 보였다. 한편 해조군집의 종다양성지수는 빈도, 피도, 빈도와 피도 합 그리고 중요도를 기준으로 계산한 결과, 각각 1.81, 2.25, 2.19, 1.80로 나타났다. 이는 종다양성지수의 계산을 위한 기준자료에 따라 값이 달라짐을 의미하는 것으로, 차후 종다양서지수를 논할 때 기본자료 선택의 중요성과 방법론의 표준화가 필요함을 지적한 것이다. 한편 본 연구에서 분류된 해조류 종수는 부산연안에서 기 조사된 결과와 비교할 때 최고 65%까지 감소한 것으로 나타났다.

• The Journal of Asian Finance, Economics and Business
• /
• 제8권3호
• /
• pp.1113-1119
• /
• 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.

• 한국잡초학회지
• /
• 제4권1호
• /
• pp.4-10
• /
• 1984

전북지역(全北地域)의 밭 잡초식생변화(雜草植生變化)를, 재배작물별(栽培作物別) 및 경지형태별(耕地形態別) 조사(調査)하였다. 1. 전북지역(全北地域) 밭에 발생하는 잡초(雜草)는 18과(科) 44종(種)으로, 일년초(一年草) 22종(種), 월년초(越年草) 11종(種) 및 다년초(多年草) 9종(種)으로 구성(構成)되어 있었다. 발생빈도별(發生頻度別)로 보면, 바랭이가 67.2%로 가장 높았으며, 다음으로 쇠비름, 명아주, 망초의 순위(順位)였다. 3. 조사지역(調査地域)의 약(約) 60%에 해당(該當)되는 지역(地域)의 잡초식생(雜草植生)이 Simpson 지수(指數) 0.20에서 0.50사이를 나타내었다. 4. 밭에서의 Simpson 지수(指數)는 계절적(季節的)으로 변화(變化)되어, 6월(月)8일(日)의 0.65가 11월(月)10일(日)에 0.15로 감소(減少)되어 잡초식생(雜草植生)이 다양화(多樣化)되고 있음을 나타내었다. 5. 경지형태별(耕地形態別)로 보면 답이작전(沓裏作田)에서는 독새풀과 여뀌, 숙전(熟田)에서는 바랭이와 쇠비름이 우점종(優占種)이었고 야산개간지(野山開墾地)에서는 쑥을 비롯한 다양(多樣)한 초종(草種)들이 고루 발생(發生)하고 있었다. 6. 콩을 비롯한 5개 작물포(作物圃)의 Simpson 지수(指數)는 평균(平均) 0.4로써 작물(作物)의 종류(種類)에 관계없이 쇠비름과 바랭이가 우점종(優占種)이었고, 여뀌, 명아주, 쇠비름, 망초 등이 차우점종(次優占種)으로 나타났다.

• 한국잡초학회지
• /
• 제8권1호
• /
• pp.1-8
• /
• 1988

본(本) 연구(硏究)는 원예작물(園藝作物) 경작지(耕作地)에서 잡초방제방법(雜草防除方法)을 확립(確立)하는데 필요(必要)한 기초자료(基礎資料)를 얻고저 마늘은 월동전(越冬前)인 1984년(年)과 월동후(越冬後)인 1985년(年), 고추는 1985년(年)에 천원(天原), 아산(牙山), 서천(舒川), 유성(儒城) 4개(個) 지역(地域)에서 2개(個) 지점(地點)을 선정(選定)하여 약(約) 15일(日) 간격(間隔)으로 잡초(雜草)를 채취(採取)하여 잡초수(雜草數), 건물중(乾物重), 발생잡초(發生雜草)의 종생태적(種生態的) 및 사회적(社會的) 특성(特性) 분석(分析)과 우점도(優占度)를 구명(究明)하였다. 1. 마늘경작지(耕作地)에 발생(發生)하는 초종(草種)은 27과(科) 68종(種)이었으며 우점초종(優占草種)은 쇠비름, 명아주, 바랭이였고 차우점초종(次優占草種)은 쇠뜨기, 둑새풀, 강아지풀이었으며 발생잡초(發生雜草)의 본수(本數)는 5월(月), 건물종(乾物種)은 6월(月)에 가장 많았고 마늘재배기간(栽培期間) 동안 여름 광엽잡초(廣葉雜草)가 가장 많이 발생(發生)하였다. 2. 고추경작지(耕作地)에서는 17과(科) 38종(種)의 잡초(雜草)가 발생(發生)했으며 바랭이, 방동사니, 쇠비름이 우점(優占)하였고 피, 왕바랭이, 민바랭이, 중대가리풀 등이 차우점(次優占)했으며 발생잡초(發生雜草)의 본수(本數)는 6월(月)에 많았고 건물중(乾物重)은 6월(月)과 10월(月)에 낮았던 것을 제외하면 재배기간(栽培期間) 동안 큰 차이가 없었으며 여름 화본과(禾本科)와 여름 광엽잡초(廣葉雜草)는 6, 7월(月)에 발생(發生)이 많았다. 3. 고추경작지(耕作地), 마늘경작지(耕作地)에서 시기별(時期別) 종다양도(種多樣度), 최대종다양도(最大種多樣度)와 안정도(安定度)가 높아 발생초종(發生草種)이 많은 숙전(熟田)이었으며 Simpson 지수(指數)도 높아 몇 초종(草種)이 우점(優占)하는 군락(群落)이었고 종간경쟁(種間競爭)이 종내경쟁(種內競爭)보다 높아 초종간(草種間) 경쟁(競爭)이 많았다.

• 전기학회논문지
• /
• 제58권6호
• /
• pp.1078-1086
• /
• 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
• /
• 제28권7호
• /
• pp.1038-1043
• /
• 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.