• Title/Summary/Keyword: skewed distribution

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Indian Research on Artificial Neural Networks: A Bibliometric Assessment of Publications Output during 1999-2018

  • Gupta, B.M.;Dhawan, S.M.
    • International Journal of Knowledge Content Development & Technology
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    • v.10 no.4
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    • pp.29-46
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    • 2020
  • The paper describes the quantitative and qualitative dimensions of artificial neural networks (ANN) in India in the global context. The study is based on research publications data (8260) as covered in the Scopus database during 1999-2018. ANN research in India registered 24.52% growth, averaged 11.95 citations per paper, and contributed 9.77% share to the global ANN research. ANN research is skewed as the top 10 countries account for 75.15% of global output. India ranks as the third most productive country in the world. The distribution of research by type of ANN networks reveals that Feed Forward Neural Network type accounted for the highest share (10.18% share), followed by Adaptive Weight Neural Network (5.38% share), Feed Backward Neural Network (2.54% share), etc. ANN research applications across subjects were the largest in medical science and environmental science (11.82% and 10.84% share respectively), followed by materials science, energy, chemical engineering and water resources (from 6.36% to 9.12%), etc. The Indian Institute of Technology, Kharagpur and the Indian Institute of Technology, Roorkee lead the country as the most productive organizations (with 289 and 264 papers). Besides, the Indian Institute of Technology, Kanpur (33.04 and 2.76) and Indian Institute of Technology, Madras (24.26 and 2.03) lead the country as the most impactful organizations in terms of citation per paper and relative citation index. P. Samui and T.N. Singh have been the most productive authors and G.P.S.Raghava (86.21 and 7.21) and K.P. Sudheer (84.88 and 7.1) have been the most impactful authors. Neurocomputing, International Journal of Applied Engineering Research and Applied Soft Computing topped the list of most productive journals.

Skewed Inheritance of EST-SSR Alleles in Reciprocal Crosses of Cut Roses (절화장미 품종간 정역교배에 있어서 EST-SSR 마커의 유전)

  • Kim, Jin-Ki;Ahn, Dong-Chun;Oh, Hye-Jeong;Kim, Kwang-Hwan;Choi, Young-Mi;Oh, Seung-Yong;Kang, Nam-Jun;Jeong, Byoung-Ryong;Kim, Zhoo-Hyeon;Park, Young-Hoon
    • Horticultural Science & Technology
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    • v.28 no.4
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    • pp.618-626
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    • 2010
  • Matroclinal inheritance of morphological characters in interspecific crosses of Rosa spp. can be influenced by cytoplasmic inheritance, apomixis, and asynaptic heterogamy. In asynaptic heterogamy, which is often observed from interspecific crosses of Rosa sect. $Caninae$, the polyploidy of the seed parent (especially for 5x=35) is recovered in the progeny through the pollens that include only a set of bivalents (x=7) and egg cells that contain a set of bivalents (x=7) and other univalents (3x=21). In this study, we investigated the causes of matroclinal offsprings observed from reciprocal crosses of tetraploid cut rose cultivars ($Rosa$ $hybrida$ L.) by analyzing EST-SSR marker distribution in the progeny populations. From EST-SSR marker analysis of eight offsprings per six reciprocal crosses among six cultivars, cases of cytoplasmic inheritance were not observed. Apomixis was also very rare as compared to the reports on interspecific crosses of sect. $Caninae$; only one apomitic plant was identified from the cross 'Redtem' ${\times}$ 'Red Sandra'. Although a clear-cut pattern of asynaptic heterogamy was not found, cultivar-specific marker transmission skewed to seed parent in four cultivars implied that genetic inheritance can be highly influenced by the seed parent depending on crosses among cut rose cultivars; especially, 10 out of 11 alleles specific to 'Yellow King' distributed in progenies at higher ratios when the cultivars were crossed as the seed parent.

Sedimentary Facies and Geochemical Characteristics of Upper Intertidal Zone, Southwestern Coast, Korea (한반도 남서해안 상부조간대의 퇴적상 및 지구화학적 특성)

  • Kang, Suk-Bum;Koh, Young-Koo;Park, Bae-Young;Youn, Seok-Tai;Kim, Joo-Yong;Oh, Kang-Ho;Shin, Sang-Eun
    • Journal of the Korean earth science society
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    • v.23 no.8
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    • pp.722-735
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    • 2002
  • In order to reveal sedimentary facies and geochemical characteristics on sediments distributed in upper intertidal zone, the southwestern coast of Korea, grain size and metal content analyses to the sediments were carried out. The grain size distribution of sediments shows very wide range from gravel to mud. The sediments are very well sorted to very poorly sorted and mostly positively skewed. Geochemical behavior of metals in the sediments is dependant on grain size, in part, but might be much controlled by complex submarine topography, highly varied tidal currents and surrounding land geology in the study area. Igeo (index of geoaccumulation) representing metal condensation in the sediments moderately/strongly polluted in Co and Cr and moderately polluted in Cu and Ni. But notable metal condensations are not found in the study area. So, it might be interpreted that grain size and metal content distribution tendencies in the sediments are considerably influenced by complex submarine topography, highly varied tidal currents and surrounding land geology.

Trend Analysis of Extreme Precipitation Using Quantile Regression (Quantile 회귀분석을 이용한 극대강수량 자료의 경향성 분석)

  • So, Byung-Jin;Kwon, Hyun-Han;An, Jung-Hee
    • Journal of Korea Water Resources Association
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    • v.45 no.8
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    • pp.815-826
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    • 2012
  • The underestimating trend using existing ordinary regression (OR) based trend analysis has been a well-known problem. The existing OR method based on least squares approximate the conditional mean of the response variable given certain values of the time t, and the usual assumption of the OR method is normality, that is the distribution of data are not dissimilar form a normal distribution. In this regard, this study proposed a quantile regression that aims at estimating either the conditional median or other quantiles of the response variable. This study assess trend in annual daily maximum rainfall series over 64 weather stations through both in OR and QR approach. The QR method indicates that 47 stations out of 67 weather stations are a strong upward trend at 5% significance level while OR method identifies a significant trend only at 13 stations. This is mainly because the OR method is estimating the condition mean of the response variable. Unlike the OR method, the QR method allows us flexibly to detect the trends since the OR is designed to estimate conditional quantiles of the response variable. The proposed QR method can be effectively applied to estimate hydrologic trend for either non-normal data or skewed data.

The Distribution Characteristics of Grain Size and Organic Matters of Surface Sediments from the Nakdong-Goryeong Mid-watershed (낙동·고령 중권역의 표층 퇴적물 입도 조성 및 유기물질 분포 특성 변화)

  • Kim, Shin;Ahn, Jungmin;Kim, Hyounggeun;Kwon, Heongak;Kim, Gyeonghoon;Shin, Dongseok;Yang, Deukseok
    • Journal of Environmental Science International
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    • v.27 no.6
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    • pp.411-423
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    • 2018
  • To investigate the distribution characteristics of grain size and organic matter of surface sediments from the Nakdong-Goryeong Mid-watershed, surface sediments were collected and analyzed. The samples were collected from six sited at four different times between May 2013 and May 2014. The were analyzed for grain size, water content, ignition loss, chemical oxygen demand, total organic carbon and total nitrogen. The surface sediments were mainly composed of medium sand (mean 44.7%) and coarse sand (mean 32.8%) and became coarser in May 2014. Fine sediments at the site NG-2 were poorly sorted and positively skewed, and occur in a tributary environment that is relatively low-energy compared with the other sites. The water content at the studied sites (15.3 ~ 34.9%) averaged 20.25%, and ignition loss (0.4 ~ 5.8%) and total nitrogen (274 ~ 2493 mg/kg) averaged 1.33% and, 696 mg/kg, respectively. These values indicated that the sediments were not seriously contaminated when compared with the sediment pollution evaluation standard of the National Institute of Environmental Research. The chemical oxygen demand (mean 0.17%) was at the non-polluted level compared with United States Environmental Protection Agency sediment quality standards. The total organic carbon (mean 0.18%) at all sites except site NG-2 (lowest effect level) was the no effect level of the Ontario sediment quality guidelines. The COD/IL (0.02 ~ 0.20) and C/N (0.73 ~ 6.76) were less than 1 and 10, respectively. Organic matter in the study area produced naturally from aquatic organisms. Results of principal component analysis showed that fine sediments (very fine sand and silt) were significantly affected by organic matters (ignition loss, chemical oxygen demand, total organic carbon and total nitrogen). In addition, the highest organic matters content in the study area occurred at the site with the finest sediments (NG-2).

Evaluation of Cold Tolerance-Related Traits of Recombinant Inbred Lines in Rice (벼 재조합 자식계통의 내냉성 관련 형질 분석)

  • Jeong Eung Gi;Ahn Sang Nag;Yea Jong Doo;Baek Man Kee;Choi Hae Chune;Yi Gihwan;Nam Min-Hee;Yoon Kyung Min
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.50 no.3
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    • pp.205-211
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    • 2005
  • This study was carried out to construct cold-tolerance characteristics. The RILs were developed from progenies of a cross between cold-susceptible Tongil-type rice variety, Milyang 23 and cold-tolerant Japonica rice variety, Stejaree 45 by single seed descent methods. The 175 RILs $(F_8)$ were evaluated for cold tolerance traits by field screening under cold-water irrigation. Frequency distribution of RILs in leaf discoloration, heading delay, culm length reduction and number of spikelets reduction displayed nearly normal distributions with transgressive segregations to either side of parents, while the spikelet fertility reduction and panicle exsertion at low-temperature showed the more or less skewed continuous distribution toward the susceptible parent. Higher heritabilities over $60\%$ were observed in leaf discoloration, spikelet fertility reduction, panicle exsertion, while relatively lower heritabilities less than $40\%$ were observed in culm length reduction, number of spikelets reduction and grain yield reduction. Some cold-tolerance RILs were selected effectively by cold water irrigation, which are expected to be good materials in breeding program for cold tolerance.

Cadmium and Lead Concentrations in Blood of Solderers among Autoworkers (자동차공장(自動車工場) 근로자중(勤勞者中) 납땜공의 혈중(血中) 카드미움과 연함량(鉛含量)에 관(關)한 조사연구(調査硏究))

  • Yun, Bae-Joung
    • Journal of Preventive Medicine and Public Health
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    • v.14 no.1
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    • pp.111-116
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    • 1981
  • Economic development of Korea brought rapid progress and expansion of her industries. Accordingly, number of workers who have been exposed to hazardous metals are increasing. For better understanding the significance of on the job human metal pollution, a total of 22 solderers among autoworkers and 28 controls among medical students was purposively selected as samples of the study. From their blood, concentrations of cadmium and lead were measured with atomic absorption spectrophotometer, and to compare with statistical indices of controls those of solderers were sumarized as follows. 1. Each frequency distribution of cadmium and lead concentration in blood of solderers was more positively skewed showing non-Gausian distribution. 2. Interindividual variation of lead concentration in blood of solderers was markedly revealed. 3. Each mean of cadmium and lead concentration in blood of solderers was higher than that of controls(Cd;p<0.01, Pb;p<0.01). 4. Relative ratio of cadmium concentration in blood of solderers to that of controls was 1.36 by arithmatic mean and 1.39 by geometric mean. Relative ratio of lead concentration in blood of solderers to that of controls was 1.53 by arithmatic mean and 1.30 by geometric mean. 5. It was shown that concentration of lead is slightly correlated with that of cadmium both in solderers and controls(solderers; p<0.1, controls;p<0.1).

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Estimation of Optimal Harvest Volume for the Long-term Forest Management Planning using Goal Programming (장기산림경영계획의 목표수확량 산출을 위한 목표계획법의 적용)

  • Won, Hyun-Kyu;Kim, Young-Hwan;Kwon, Soon-Duk
    • Journal of Korean Society of Forest Science
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    • v.98 no.1
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    • pp.125-131
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    • 2009
  • To facilitate the sustainable forest management, Forest Service in Korea has assigned 2.9 million hectare forests as 'intensive management forests' and encouraged local governments to develop a strategic management plan for their forests. One of problems for the sustainable forest management in Korea is the skewed distribution of forest age classes. Currently the majority of forestlands in Korea is occupied by age classes III and IV. In this study, we intended to find an optimum harvest volume, which enable one to make the intensive management forest in Youngdong-Gun evenly distributed for the age classes and allow an even harvest volume through a 50 year time horizon. To develop an optimization model, we applied the goal programming technique which is adequate for a multi-purpose management planning. The results indicated that it is necessary to harvest 1.2 million cubic meters in each decade to achieve the most stable distribution of age classes for the study site. The harvest volume target resulted from this study would be used in a management planning or an associated policy making process in the future.

A Cell-based Indexing for Managing Current Location Information of Moving Objects (이동객체의 현재 위치정보 관리를 위한 셀 기반 색인 기법)

  • Lee, Eung-Jae;Lee, Yang-Koo;Ryu, Keun-Ho
    • The KIPS Transactions:PartD
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    • v.11D no.6
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    • pp.1221-1230
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    • 2004
  • In mobile environments, the locations of moving objects such as vehicles, airplanes and users of wireless devices continuously change over time. For efficiently processing moving object information, the database system should be able to deal with large volume of data, and manage indexing efficiently. However, previous research on indexing method mainly focused on query performance, and did not pay attention to update operation for moving objects. In this paper, we propose a novel moving object indexing method, named ACAR-Tree. For processing efficiently frequently updating of moving object location information as well as query performance, the proposed method is based on fixed grid structure with auxiliary R-Tree. This hybrid structure is able to overcome the poor update performance of R-Tree which is caused by reorganizing of R-Tree. Also, the proposed method is able to efficiently deal with skewed-. or gaussian distribution of data using auxiliary R-Tree. The experimental results using various data size and distribution of data show that the proposed method has reduced the size of index and improve the update and query performance compared with R-Tree indexing method.

Genetic Analysis of Agronomic Characters in Interspecific Cross in Soybean (콩 종간교잡에서 주요형질의 유전분석)

  • Lee, Jeong-Dong;Kwon, Taek-Hwa;Cho, Ho-Young;Hwang, Young-Hyun
    • Current Research on Agriculture and Life Sciences
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    • v.20
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    • pp.1-8
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    • 2002
  • This study was conducted to obtain the information of varietal development using wild soybean through investigation of variation and heredity of major agronomic characters in $F_2$ generation of interspecific cross between Glycine max and G. soja. In segregating populations of two crosses, all characters observed except 100-seed weight showed transgressive segregation. Days to flowering showed normal distribution; mean days to flowering in $F_1$, and $F_2$ was approximately mean of parent. Mean of $F_1$ for 100-seed weight was 6.2g and 5.7g for Eunhakong/KLG10084 and Sohaegnamulkong/KLG10084, respectively, which were somewhat skewed distribution to small seeded parents. Mean seed yield of $F_2$ was about mean of two parents. Degree of vine was 6.4 and 5.7 in $F_1$ for two crosses but it was 6.0 in $F_2$ for Eonbakong/KLG10084, which revealed the degree of vine as partial dominance while 4.6 for Sobaegnamulkong/KLG10084, somewhat different results from the previous cross. Broad-sense heritability($h^2B$) for plant height, days to flowering, pods per plant, seed yield, and degree of vine was comparatively high and narrow-sense heritability($h^2B$) for 100-seed weight which is the moot important character in the development of small seed-size sprout soybean was 52.3% and 65.6% for Eunhakong/KLG10084 and Sohaegnamulkong/KLG10084, respectively, which indicated that selection for the character in early generation was possible.

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