• Title/Summary/Keyword: distributional analysis

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Distribution of ground beetles (Coleoptera: Carabidae) in Naejangsan National Park, Korea

  • Jung, Jong-Kook;Lee, Joon-Ho;Lee, Sue Yeon;Kim, Seung Tae
    • Korean Journal of Environment and Ecology
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    • v.29 no.2
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    • pp.200-209
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    • 2015
  • This study was conducted to investigate the distributional characteristics of ground beetles and to provide basis information for biodiversity management including the ground beetles in the Naejangsan National Park area. Pitfall traps were installed throughout 20 sites within Naejangsan National Park during 2008 to 2011 to collect ground beetles. A total of 2,409 collected ground beetles were identified with 35 species belonging to 19 genera of 8 subfamilies. Coptolabrus jankowskii jankowskii, Eucarabus sternbergi sternbergi, and Pterosticus audax were dominant at the core area, while Pheropsophus jessoensis, Synuchus nitidus, Synuchus cycloderus, and Chlaenius naeviger were dominant at the border of the National Park and adjacent to the road or grassland. These differences of dominant species also affected to the similarity of species composition between core and border area, and caused increasing dissimilarities between sites with cluster analysis. Although the result of the present study was a case study using ground beetles, it will be helpful to develop a management strategy of biodiversity conservation in Naejangsan National Park and its surroundings.

Probability Funetion of Best Fit to Distribution of Extremal Minimum Flow and Estimation of Probable Drought Flow (극소치유량에 대한 적정분포형의 설정과 확률갈수량의 산정)

  • 김지학;이순탁
    • Water for future
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    • v.8 no.1
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    • pp.80-88
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    • 1975
  • In this paper the authors established the best fit distribution function by applying the concept of probabiaity to the annual minimum flow of nine areas along the Nakdong river basin which is one of the largest Korean rivers and calculated the probable minimum flow suitable to those distribution function. Lastly, the authors tried to establish the best method to estimate the probable minimun flow by comparing some frequency analysis methods. The results obtained are as follows (1) It was considered that the extremal distribution type III was the most suitable one in the distributional types as a result of the comparision with Exponential distribution, Log-Normal distribution, Extremal distribution type-III and so on. (2) It was found that the formula of extremal distribution type-II for the estimation of probable minimum flow gave the best result in deciding the probable minimum flow of the Nakdong river basin. Therfore, it is recommended that the probable minimum flow should be estimated by using the extremal distribution type-III method. (3) It could be understood that in the probable minimum flow the average non-excessive probability appeared to be $Po{\fallingdotseq}1-\frac{1}{2T}$ and gave the same values of the probable variable without any difference in the various methods of plotting technique.

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Distributional Pattern of Tree Species in Response to Soil Variables in a Semi Natural Tropical Forest of Bangladesh

  • Ara, Saida Hossain;Limon, Mahedi Hasan;Kibria, Mohammad Golam
    • Journal of Forest and Environmental Science
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    • v.37 no.1
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    • pp.14-24
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    • 2021
  • A plant community is a group of populations that coexist in space and interact directly or indirectly with the environment. In this paper, we determined the pattern of tree species composition in response to soil variables in Khadimnagar National Park (KNP), which is one of the least studied tropical forests in Bangladesh. Soil and vegetation data were collected from 71 sample plots. Canonical Correspondence Analysis (CCA) with associated Monte Carlo permutation tests (499 permutations) was carried out to determine the most significant soil variable and to explore the relationship between tree species distribution and soil variables. Soil pH and clay content (pH with p<0.01 and Clay content with p<0.05) were the most significant variables that influence the overall tree species distribution in KNP. Soil pH is related to the distribution and abundance of Syzygium grande and Magnolia champaca, which were mostly found and dominant species in KNP. Some species were correlated with clay content such as Artocarpus chaplasha and Cassia siamea. These observations suggest that both the physico-chemical properties of soil play a major role in shaping the tree distribution in KNP. Hence, these soil properties should take into account for any tree conservation strategy in this forest.

Estimating quantiles of extreme wind speed using generalized extreme value distribution fitted based on the order statistics

  • Liu, Y.X.;Hong, H.P.
    • Wind and Structures
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    • v.34 no.6
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    • pp.469-482
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    • 2022
  • The generalized extreme value distribution (GEVD) is frequently used to fit the block maximum of environmental parameters such as the annual maximum wind speed. There are several methods for estimating the parameters of the GEV distribution, including the least-squares method (LSM). However, the application of the LSM with the expected order statistics has not been reported. This study fills this gap by proposing a fitting method based on the expected order statistics. The study also proposes a plotting position to approximate the expected order statistics; the proposed plotting position depends on the distribution shape parameter. The use of this approximation for distribution fitting is carried out. Simulation analysis results indicate that the developed fitting procedure based on the expected order statistics or its approximation for GEVD is effective for estimating the distribution parameters and quantiles. The values of the probability plotting correlation coefficient that may be used to test the distributional hypothesis are calculated and presented. The developed fitting method is applied to extreme thunderstorm and non-thunderstorm winds for several major cities in Canada. Also, the implication of using the GEVD and Gumbel distribution to model the extreme wind speed on the structural reliability is presented and elaborated.

The Cash Flow Sensitivity of Investment: A Switching Regression Approach Based on Korean Firm Data (기업투자의 현금흐름 민감도: 전환회귀법을 이용한 분석)

  • Koo, Jaewoon;Maeng, Kyunghee
    • Economic Analysis
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    • v.17 no.2
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    • pp.56-89
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    • 2011
  • The sensitivity of investment with respect to cash flow is positive in imperfect financial markets. Using a switching regression model, cash flow sensitivity of investments in chaebol firms and large firms appears to be higher. Also, investments are found to be more responsive to cash flow during monetary contraction periods. These findings imply that monetary policy works through a credit channel. Furthermore, it appears that monetary policy exerts distributional effects as well as aggregate effects on that firms are unevenly affected by monetary changes.

Geographic Distribution of Physician Manpower by Gini Index (GINI계수에 의한 의사의 지역간 분포양상)

  • Moon, Byung-Wook;Park, Jae-Yong
    • Journal of Preventive Medicine and Public Health
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    • v.20 no.2 s.22
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    • pp.301-311
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    • 1987
  • The purpose of this study is to analyze degree of geographic maldistribution of physicians and changes in the distributional pattern in Korea over the years 1980-1985. In assessing the degree of disparity in physician distribution and in identifying changes in the distributional pattern, the Gini index of concentration was used. The geographical units selected for computation of the Gini index in this analysis are districts (Gu), cities (Si), and counties (Gun). Locational data for 1980 and 1985 were obtained from the population census data in the Economic Planning Board and regular reports of physicians in the Korean Medical Association. The rates of physicians located counties to whole physicaians were 10.4% in 1980 and 9.6% in 1985. In term of the ratio of physicians per 100,000 population, rural area had 9.18 physicians in 1980 and 12.95 in 1985, 7.13 general practitioner in 1980 and 7.29 in 1955, and 2.05 specialists in 1980 and 5.66 in 1985. Only specialists of genral surgery and preventive medicine were distributed over 10% in county and distribution of every specialists except chest surgery in county increased in 1955, comparing with that rates of 1980. The Gini index computed to measure inequality of physician distribution in 1985 indicate as follows; physicians 0.3466, general practitioners 0.5479, and specialists 0.5092. But the Gini index for physicians and specialists fell -15.40% and -10.42% from 1980 to 1985, indication more even distribution. The changes in the Gini index over the period for specialists from 0.3639 to 0.4542 for districts, from 0.2510 to 0.1949 for cities, and 0.5303 to 0.5868 for counties indicate distributional change of 24.81%, -22.35%, and 10.65% respectively. The Gini indices for specialists of neuro-surgery, chest surgery, plastic surgery, ophthalmology, tuberculosis, preventive medicine, and anatomical pathology in 1985 were higher than Gini indices in 1980.

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Analysis of Catena on Representative Soils derived from Granite and Granite Gneiss

  • Sonn, Yeon-Kyu;Cho, Hyun-Jun;Hyun, Byung-Keun;Chun, Hyen-Chung;Shin, Kook-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.48 no.4
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    • pp.255-261
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    • 2015
  • Soil catena can be characterized by some properties, such as drainage levels and soil textures. Characteristics of soil catena are different drainage levels from a summit to the direction of gravity and similar soil textures. Therefore this study was performed GIS (Geographic information system) and statistical analyses using perimeters from soil series in order to characterize quantitatively and objectively soil distributional properties in Korea. The total of 16 soil series from representative granite and granite gneiss originated soils were selected among inland soils from detailed soil maps (1:25,000 scale) in Rural Development Administration (RDA) and analyzed. After the detailed soil maps were merged by soil series unit, perimeters were measured from one soil series to neighboring soil series using functions of table join, merge, dissolve, buffer, and clip in ArcGIS (10.1). The covering ratio of each soil series unit was calculated from neighboring perimeters by soil series and applied to clustering analysis. Soils that were analyzed were the total of 16 soil series; 7 of sandy loam and 9 of clay loam. As a result, analyzed soil series adjoined complicatedly such as Hyocheon series adjoined 26 series and Jisan did 276 series. The results of the clustering analysis showed that soils were clustered by soil textures except a few soil series. This study applied only one property that was a length of neighboring soil series to GIS and statistical analyses. These results were compared to existing soil groups that were classified by new-soil taxonomy, texture, soil type and drainage level. It showed that these analyses can provide soil characteristics by soil texture. Based on this study, there is a need to investigate further objectively and quantitatively in statistical analyses of soil series.

The Comprehensive Equity Implications of a Carbon Pricing Policy in South Korea: Based on Environmentally Extended Input Output Analysis Together with Household Expenditure Data (탄소가격정책의 분배적 함의: 가계동향조사자료와 환경산업연관분석 (EEIO)을 이용해)

  • Kim, Hana
    • Journal of Environmental Policy
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    • v.14 no.2
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    • pp.101-131
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    • 2015
  • A cap-and-trade program accounting for 60 percent of total national greenhouse gas emissions was launched in South Korea in 2015. Academic literature expects that the implementation of such a policy is likely to adversely impact income distribution among various socioeconomic groups in developed countries. South Korea is challenged by equity issues, as well circumstances, the distributional implications of carbon pricing policies need to be examined and reflected in the design of the program prior to implementation in order not to exacerbate social inequity. Using environmentally extended input-output analysis together with household expenditure data, this study finds that a carbon pricing policy will be regressive in South Korea, but the extent depends on whether relative burdens of a carbon pricing policy are measured based on current incomes or proxies of permanent incomes. Along with poor households, this paper finds that elderly and urban households will be more adversely impacted in South Korea. These burdens can be relieved if a small fraction of the revenue is redistributed to households.

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The Impact of Selection Attributes of School Cafeteria Consumers on Satisfaction and Behavioral Intentions - Focused on University Cafeteria Consumers (급식업체 소비자의 선택속성이 만족 및 행동의도에 미치는 영향에 관한 연구: 대학교 급식업체 소비자를 중심으로)

  • Choi, Soon-Tae;Lee, Soo-Bum
    • Culinary science and hospitality research
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    • v.17 no.3
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    • pp.65-75
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    • 2011
  • The purpose of the study was to explore the relationship between satisfaction and future behavior intention of cafeteria users. Respondents of the research were cafeteria users in major colleges in Kyunggi province. A total of 300 questionnaires were distributed between October 1, 2010 and October 20, 2010 but only281 questionnaires were used for the analysis. Based on 14 selection attributes, factor analysis showed that the KMO value of 0.634, which was extracted by Verimax vertical rotation, and=610.084(p<0.001). In addition, the distributional explanation showed a total of 61.685%. Five factors were obtained as ingredients, food, menu, maintenance, and internal environment factors according to the feature of each variable. The Cronbach value according to confidence and validity tests was 0.703. The explanation was 16.3% and the influence on satisfaction included ingredients, maintenance, and internal environment. The effect on future behavior intention was significant at the level of p<0.001. This study has limitations in that it has generalized the findingson consumers of university cafeterias; therefore, follow-up studies must be conducted.

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Analysis of Accelerated Aging Natural Ester Oil and Mineral Oil in Distributional Transformers (배전용 변압기에서의 고온열화와 열 사이클 열화에 따른 식물유와 광유의 특성 분석)

  • An, Jung-Sik;Choi, Sun-Ho;Bang, Jeong-Ju;Jung, Joong-Il;Huh, Chang-Su
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.6
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    • pp.1163-1168
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    • 2011
  • Most transformers use insulating and cooling fluids derived from petroleum crude oil, but mineral oil has some possibility of environmental pollution and fire with explosion. vegetable oil fluids extracted from seed has superior biodegradation and fire-resistant properties including an exceptionally high fire point enhancing fire safety. In this study, it is aimed at the practicality of substituting natural ester dielectric fluid for mineral oil in liquid insulation system of transformers. As a rise in coil winding temperature has a direct influence on transformer life time, it is important to evaluate the temperature rise of coil winding in vegetable oil in comparison with mineral oil. Four transformers for the test are designed with 10KVA, 13.2KV, one phase unit. The temperature are directly measured in insulating oil of these transformers with the two sorts of natural ester and mineral oil dielectric fluid respectively. Experiment for aging carry out two means. First means remained $120^{\circ}C$ that transformer of mineral oil were operated at 185% load. Second means is that insulating oils of two natural ester and mineral oil were aged by thermal cycles repeating from $30^{\circ}C$ to $120^{\circ}C$. For the heating, Transformers were operated at 185% load. For the cooling, cooling system was operated in the chamber. Samples were analyzed at 42, 63, 93, 143, 190, 240 300cycles. Analysis contents are dielectric strength, total acid value. Mineral oils compared results of first means with results of second means. And compared two sort natural esters respectively with mineral oil in second means.