• Title/Summary/Keyword: k-mean clustering

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Population structure analysis of Yeonsan Ogye using microsatellite markers

  • Cho, Sung Hyun;Lee, Seung-Sook;Manjula, Prabuddha;Kim, Minjun;Lee, Seung Hwan;Lee, Jun Heon;Seo, Dongwon
    • Journal of Animal Science and Technology
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    • v.62 no.6
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    • pp.790-800
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    • 2020
  • The Yeonsan Ogye (YO) chicken is a natural heritage of Korea, characterized by black feathers, skin, bones, eyes, and comb. The purebred of YO population has been reared under the natural mating system with no systematic selection and breeding plan. The purpose of this study was to identify the genetic diversity and find the optimal number of population sub-division using 12 polymorphic microsatellite (MS) markers to construct a pedigree-based breeding plan for the YO population. A total of 509 YO birds were used for this study. Genetic diversity and population structure analysis were conducted based on the MS marker genotype information. The overall average polymorphic information content value and expected heterozygosity of the population were 0.586, and 0.642, respectively. The K-mean cluster analysis based on the genetic distance result confirmed that the current YO population can be divided into three ancestry groups. Individuals in each group were evaluated based on their genetic distance to identify the potential candidates for a future breeding plan. This study concludes that a future breeding plan with known pedigree information of selected founder animals, which holds high genetic diversity, could be the best strategy to ensure the conservation of the Korean YO chicken population.

A New Fast EM Algorithm (새로운 고속 EM 알고리즘)

  • 김성수;강지혜
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.10
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    • pp.575-587
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    • 2004
  • In this paper. a new Fast Expectation-Maximization algorithm(FEM) is proposed. Firstly the K-means algorithm is modified to reduce the number of iterations for finding the initial values that are used as the initial values in EM process. Conventionally the Initial values in K-means clustering are chosen randomly. which sometimes forces the process of clustering converge to some undesired center points. Uniform partitioning method is added to the conventional K-means to extract the proper initial points for each clusters. Secondly the effect of posterior probability is emphasized such that the application of Maximum Likelihood Posterior(MLP) yields fast convergence. The proposed FEM strengthens the characteristics of conventional EM by reinforcing the speed of convergence. The superiority of FEM is demonstrated in experimental results by presenting the improvement results of EM and accelerating the speed of convergence in parameter estimation procedures.

Assessment of Population Structure and Genetic Diversity of 15 Chinese Indigenous Chicken Breeds Using Microsatellite Markers

  • Chen, Guohong;Bao, Wenbin;Shu, Jingting;Ji, Congliang;Wang, Minqiang;Eding, Herwin;Muchadeyi, Farai;Weigend, Steffen
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.3
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    • pp.331-339
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    • 2008
  • The genetic structure and diversity of 15 Chinese indigenous chicken breeds was investigated using 29 microsatellite markers. The total number of birds examined was 542, on average 36 birds per breed. A total of 277 alleles (mean number 9.55 alleles per locus, ranging from 2 to 25) was observed. All populations showed high levels of heterozygosity with the lowest estimate of 0.440 for the Gushi chickens, and the highest one of 0.644 observed for Wannan Three-yellow chickens. The global heterozygote deficit across all populations (FIT) amounted to 0.180 (p<0.001). About 16% of the total genetic variability originated from differences between breeds, with all loci contributing significantly to this differentiation. An unrooted consensus tree was constructed using the Neighbour-Joining method and pair-wise distances based on marker estimated kinships. Two main groups were found. The heavy-body type populations grouped together in one cluster while the light-body type populations formed the second cluster. The STRUCTURE software was used to assess genetic clustering of these chicken breeds. Similar to the phylogenetic analysis, the heavy-body type and light-body type populations separated first. Clustering analysis provided an accurate representation of the current genetic relations among the breeds. Remarkably similar breed rankings were obtained with all methods.

A Systematic Design of Automatic Fuzzy Rule Generation for Dynamic System

  • Kang, Hoon;Kim, Young-Ho;Jeon, Hong-Tae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.2 no.3
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    • pp.29-39
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    • 1992
  • We investigate a systematic design procedure of automatic rule generation of fuzzy logic based controllers for highly nonlinear dynamic systems such as an engine dynamic modle. By "automatic rule generation" we mean autonomous clustering or collection of such meaningful transitional relations from one conditional subspace to another. During the design procedure, we also consider optimaly control strategies such as minimum squared error, near minimum time, minimum energy or combined performance critiera. Fuzzy feedback control systems designed by our method have the properties of closed-loop stability, robustness under parameter variabitions, and a certain degree of optimality. Most of all, the main advantage of the proposed approach is that reliability can be potentially increased even if a large grain of uncertainty is involved within the control system under consideration. A numerical example is shown in which we apply our strategic fuzzy controller dwsign to a highly nonlinear model of engine idling speed control.d control.

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An Investigation of the Relationship between Revenue Water Ratio and the Operating and Maintenance Cost of Water Supply Network (상수관망 유수율과 유지관리 비용의 관계 분석)

  • Kim, Jaehee;Yoo, Kwangtae;Jun, Hwandon;Jang, Jaesun
    • Journal of Korean Society on Water Environment
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    • v.28 no.2
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    • pp.202-212
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    • 2012
  • Due to the deterioration of water supply network and the deficiency of raw water, the water utility of local governments have performed various projects to improve their revenue water ratio. However, it is very difficult to estimate the cost for maintaining the revenue water ratio at higher level after completing the project, because local governments have different conditions affecting the operating and maintenance cost of water supply network. The purpose of this study is to present a procedure to estimate the operating and maintenance cost required to maintain the target revenue water ratio of the water supply network. For this purpose, we estimated the cost used only for operation and maintenance of water supply network of 164 local governments with the aid of K-Mean Clustering Analysis and the data from 40 representative local governments. Then, the regression analysis was performed to find relationship between revenue water ratio and the operating and maintenance cost with two different data sets generated by two classification methods; the first method classifies the local governments by means of k-means clustering, and the other classifies the local governments according to the index standardized by the operating and maintenance cost per unit length of water mains per revenue water ratio. The results shows that the method based on the index standardized by the cost and revenue water ratio of each government produces more reliable results for finding regression equations between revenue water ratio and the operating and maintenance cost only for water supply network. The estimated regression equations for each group can be used to estimate the cost required to keep the target revenue water ratio of the local government.

Toxicogenomics Analysis on Thioacetamide-induced Hepatotoxicity in Mice

  • Lim, Jung-Sun;Jeong, Sun-Young;Hwang, Ji-Yoon;Park, Han-Jin;Cho, Jae-Woo;Yoon, Seok-Joo
    • Molecular & Cellular Toxicology
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    • v.2 no.2
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    • pp.126-133
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    • 2006
  • Thioacetamide (TA) is well known hepatotoxic and hepatocarcinogenic agent. TA also diminishes the contents of hepatic cytochrome P450 and inhibits the enzyme activity of the hepatic mixed function oxidases. TA metabolite, thioacetamide-s-oxide, is further transformed into a still unknown highly reactive metabolite that binds to macromolecules. In this study, we focused on TA-induced gene expression at hepatotoxic dose. Mice were exposed to two levels (5 mg/kg or 50 mg/kg i.p.) of TA, sampled at 6 or 24 h, and hepatic gene expression levels were determined to evaluate dose and time dependent changes. We evaluated hepatotoxicity by serum AST and ALT level and histopathological observation. Mean serum activities of the liver leakage enzymes, AST and ALT, were slightly increased compare to control. H & E and PAS evaluation of stained liver sections revealed TA-associated histopathological finding in mice. Centrilobular eosinophilic degeneration was observed at high dose-treated mice group. Hepatic gene expression was analyzed by QT clustering. Clustering of high dose-treated samples with TA-suggests that gene expressional changes could be associated from toxicity as measured by traditional biomarkers in this acute study.

Effect of Annealing of Nafion Recast Membranes Containing Ionic Liquids

  • Park, Jin-Soo;Shin, Mun-Sik;Sekhon, S.S.;Choi, Young-Woo;Yang, Tae-Hyun
    • Journal of the Korean Electrochemical Society
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    • v.14 no.1
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    • pp.9-15
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    • 2011
  • The composite membranes comprising of sulfonated polymers as matrix and ionic liquids as ion-conducting medium in replacement of water are studied to investigate the effect of annealing of the sulfonated polymers. The polymeric membranes are prepared on recast Nafion containing the ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate ($EMIBF_4$). The composite membranes are characterized by thermogravitational analyses, ion conductivity and small-angle X-ray scattering. The composite membranes annealed at $190^{\circ}C$ for 2 h after the fixed drying step showed better ionic conductivity, but no significant increase in thermal stability. The mean Bragg distance between the ionic clusters, which is reflected in the position of the ionomer peak (small-angle scattering maximum), is larger in the annealed composite membranes containing $EMIBF_4$ than the non-annealed ones. It might have been explained to be due to the different level of ion-clustering ability of the hydrophilic parts (i.e., sulfonic acid groups) in the non- and annealed polymer matrix. In addition, the ionic conductivity of the membranes shows higher for the annealed composite membranes containing $EMIBF_4$. It can be concluded that the annealing of the composite membranes containing ionic liquids due to an increase in ion-clustering ability is able to bring about the enhancement of ionic conductivity suitable for potential use in proton exchange membrane fuel cells (PEMFCs) at medium temperatures ($150-200^{\circ}C$) in the absence of external humidification.

A study on solar radiation prediction using medium-range weather forecasts (중기예보를 이용한 태양광 일사량 예측 연구)

  • Sujin Park;Hyojeoung Kim;Sahm Kim
    • The Korean Journal of Applied Statistics
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    • v.36 no.1
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    • pp.49-62
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    • 2023
  • Solar energy, which is rapidly increasing in proportion, is being continuously developed and invested. As the installation of new and renewable energy policy green new deal and home solar panels increases, the supply of solar energy in Korea is gradually expanding, and research on accurate demand prediction of power generation is actively underway. In addition, the importance of solar radiation prediction was identified in that solar radiation prediction is acting as a factor that most influences power generation demand prediction. In addition, this study can confirm the biggest difference in that it attempted to predict solar radiation using medium-term forecast weather data not used in previous studies. In this paper, we combined the multi-linear regression model, KNN, random fores, and SVR model and the clustering technique, K-means, to predict solar radiation by hour, by calculating the probability density function for each cluster. Before using medium-term forecast data, mean absolute error (MAE) and root mean squared error (RMSE) were used as indicators to compare model prediction results. The data were converted into daily data according to the medium-term forecast data format from March 1, 2017 to February 28, 2022. As a result of comparing the predictive performance of the model, the method showed the best performance by predicting daily solar radiation with random forest, classifying dates with similar climate factors, and calculating the probability density function of solar radiation by cluster. In addition, when the prediction results were checked after fitting the model to the medium-term forecast data using this methodology, it was confirmed that the prediction error increased by date. This seems to be due to a prediction error in the mid-term forecast weather data. In future studies, among the weather factors that can be used in the mid-term forecast data, studies that add exogenous variables such as precipitation or apply time series clustering techniques should be conducted.

Chaotic Features for Traffic Video Classification

  • Wang, Yong;Hu, Shiqiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.8
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    • pp.2833-2850
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    • 2014
  • This paper proposes a novel framework for traffic video classification based on chaotic features. First, each pixel intensity series in the video is modeled as a time series. Second, the chaos theory is employed to generate chaotic features. Each video is then represented by a feature vector matrix. Third, the mean shift clustering algorithm is used to cluster the feature vectors. Finally, the earth mover's distance (EMD) is employed to obtain a distance matrix by comparing the similarity based on the segmentation results. The distance matrix is transformed into a matching matrix, which is evaluated in the classification task. Experimental results show good traffic video classification performance, with robustness to environmental conditions, such as occlusions and variable lighting.

Genetic Diversity among the Genera Allium in Mongolia Based on Random Amplified Polymorphic DNA (RAPD) Analysis

  • Chun, Jong-Un;Bae, Chang-Hyu
    • Plant Resources
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    • v.4 no.3
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    • pp.121-129
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    • 2001
  • Intraspecific genetic diversity of sixteen accessions of Mogolian Alliums including fifteen species was investigated using randomly amplified polymorphic DNA (RAPD) analysis. Twenty three out of forty primers revealed scorable polymorphism. A total of 440 RAPD markers were generated on the 16 accessions of Mongolian Alliums. Among 440 RAPDs assayed, 439 were polymorphic with a mean polymorphic rate of 99.7%. Unweighted pair-group method using an arithmetic average (UPGMA) cluster analysis using RAPD data separated the 16 Allium accessions into two broad groups at similarity index 0.70. The clustering of the species was closely related with previous classification between A. altaicum and A. fistulosum. In addition, a high genetic similarity was showed between A. cepa and A. tagar.

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