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Discrete Circular Distributions with Applications to Shared Orthologs of Paired Circular Genomes

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Computer Modeling in Engineering & Sciences 2020年第6期123卷 1131-1149页

作者： Tomoaki Imoto Grace S.Shieh Kunio Shimizu School of Management and Information University of ShizuokaShizuokaJapan institute of statistical Science Academia SinicaTaipeiTaiwan School of statistical Thinking The Institute of Statistical MathematicsTokyoJapan

For structural comparisons of paired prokaryotic genomes,an important topic in synthetic and evolutionary biology,the locations of shared orthologous genes(henceforth orthologs)are observed as binned *** and other data,e.g.,wind directions recorded at monitoring sites and intensive care unit arrival times on the 24-hour clock,are counted in binned circular arcs,thus modeling them by discrete circular distributions(DCDs)is *** propose a novel method to construct a DCD from a base continuous circular distribution(CCD).The probability mass function is defined to take the normalized values of the probability density function at some pre-fixed equidistant points on the *** families of constructed DCDs which have normalizing constants in closed form are *** studies show that DCDs outperform the corresponding CCDs in modeling grouped(discrete)circular data,and minimum chi-square estimation outperforms maximum likelihood estimation for *** apply the constructed DCDs,invariant wrapped Poisson and wrapped discrete skew Laplace to compare the structures of paired bacterial ***,discrete four-parameter wrapped Cauchy(nonnegative trigonometric sums)distribution models multi-modal shared orthologs in Clostridium(Sulfolobus)better than the others considered,in terms of AIC and Freedman’s goodness-of-fit *** result that different DCDs fit the shared orthologs is consistent with the fact they belong to two ***,these prokaryotes have a common favored site around 70°on the unit circle;this finding is important for building synthetic prokaryotic genomes in synthetic *** DCDs can also be applied to other binned circular data.

关键词： Bacterial genomes circular distribution goodness-of-fit test modeling synthetic and evolutionary biology.

Groundwater fluoride contamination:A reappraisal

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Geoscience Frontiers 2015年第2期6卷 277-284页

作者： Amlan Banerjee Geological Studies Unit Indian Statistical Institute

Dissolution of fluorite （CaF2） and/or fluorapatite （FAP） [Cas（PO4）3F], pulled by calcite precipitation, is thought to be the dominant mechanism responsible for groundwater fluoride （F） contamination. Here, one dimensional reactive-transport models are developed to test this mechanism using the published dissolution and precipitation rate kinetics for the mineral pair FAP and calcite. Simulation results correctly show positive correlation between the aqueous concentrations of F and CO2 and negative correlation between F- and Ca^2＋. Results also show that precipitation of calcite, contrary to the present understanding, slows down the FAP dissolution by 10G orders of magnitude compared to the FAP dissolution by hydrolysis. For appreciable amount of fluoride contamination rock-water interaction time must be long and of order 106 years.

关键词： Fluoride Contamination Dissolution Precipitation Reactive transport model

A New Line Symmetry Distance and Its Application to Data Clustering

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Journal of Computer Science & Technology 2009年第3期24卷 544-556页

作者： Sriparna Saha Sanghamitra Bandyopadhyay Machine Intelligence Unit Indian Statistical InstituteKolkataIndia

In this paper, at first a new line-symmetry-based distance is proposed. The properties of the proposed distance are then elaborately described. Kd-tree-based nearest neighbor search is used to reduce the complexity of computing the proposed line-symmetry-based distance. Thereafter an evolutionary clustering technique is developed that uses the new linesymmetry-based distance measure for assigning points to different clusters. Adaptive mutation and crossover probabilities are used to accelerate the proposed clustering technique. The proposed GA with line-symmetry-distance-based （GALSD） clustering technique is able to detect any type of clusters, irrespective of their geometrical shape and overlapping nature, as long as they possess the characteristics of line symmetry. GALSD is compared with the existing well-known K-means clustering algorithm and a newly developed genetic point-symmetry-distance-based clustering technique （GAPS） for three artificial and two real-life data sets. The efficacy of the proposed line-symmetry-based distance is then shown in recognizing human face from a given image.

关键词： unsupervised classification clustering symmetry property line-symmetry-based distance Kd-tree genetic algorithm face recognition

Influence of Solvent-Solvent and Solute-Solvent Interaction Properties on Solvent-Mediated Potential

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Communications in Theoretical Physics 2005年第2X期44卷 365-370页

作者： ZHOU Shi-Qi institute of Modern statistical Mechanics Zhuzhou Institute of Technology Zhuzhou 412008 China

A recently proposed universal calculational recipe for solvent-mediated potential is applied to calculate excess potential of mean force between two large Lennard-Jones (LJ) or hard core attractive Yukawa particles immersed in small LJ solvent bath at supercritical state. Comparison between the present prediction with a hypernetted chain approximation adopted for solute-solute correlation at infinitely dilute limit and existing simulation data shows high accuracy for the region with large separation, and qualitative reliability for the solute particle contact region. The calculational simplicity of the present recipe allows for a detailed investigation on the effect of the solute-solvent and solvent-solvent interaction details on the excess potential of mean force. The resultant conclusion is that gathering of solvent particles near a solute particle leads to repulsive excess PMF, while depletion of solvent particles away from the solute particle leads to attractive excess PMF, and minor change of the solvent-solvent interaction range has large influence on the excess PMF.

关键词： excess potential of mean force density function theory

MATRIX NORM VERSIONS OF THE KANTOROVICH INEQUALITY AND ITS APPLICATIONS

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Applied Mathematics(A Journal of Chinese Universities) 1995年第2期10卷 133-140页

作者： YANG HU statistical Mathematics institute of Chongqing Jiaotong institute Chongqing

In this paper we discuss the generalizations of the Kaotorovich inequality and obtain some generalized Kantorovich inequalities in the sense of matrix norm. We further illustrate how to use these inequalities to deter... 详细信息

关键词： Condition number singular value decomposition orthogonal invariant norm relative efficiency.

How parents' education and working status affect the nutrition and immunization status of preschool children in India

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Asian Pacific Journal of Tropical Medicine 2008年第4期1卷 49-60页

作者： Bharati P Pal M Bharati S Biological Anthropology Unit Indian Statistical InstituteKolkata-700108India Economic Research Unit Indian Statistical InstituteKolkata-700108India Sociological Research Unit Indian Statistical InstituteKolkata-700108India

Objective:The aim of the paper is to see how educational and working status of the parents affect the nutritional and immunization status of preschool children in ***:We have used data of more than 24 000 preschool children spread over different states in *** data were collected by National Family Health Survey(NFHS-2) in *** assessing the nutritional status,only the Z-scores of weight-forheight (WHZ) have been computed and for immunization status,it has been seen whether BCG,DPT3,Polio3 and measles have been *** who fall below -2SD(-3SD) from median are considered to be moderately(severely) ***:According to the NFHS-2 data,70%of children are vaccinated by BCG,50%receive the full course of DPT,54%get all the three dozes of polio and only 42%are protected from measles by vaccination in *** percentages of moderately and severely wasted children in India are 12.1 and 2.8,*** is a marked regional variation of these *** and multivariate analysis clearly points to the need of educational status of mothers rather than fathers for proper nutritional and immunization status of preschool ***’occupation and working status also have some effect,but not so pronounced as parents’***:The Indian preschool children need particular attention for high risk of wasting and low *** prevalence of malnutrition can be arrested more by improving the mother’s education level rather than their fathers and by raising the standard of living of their house-holds.

关键词： Wasting Immunization Education Mothers working status SLI Preschool children India

Theoretical Investigation of Uniform and Non-uniform Penetrable Sphere Fluid

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Communications in Theoretical Physics 2006年第2X期46卷 323-331页

作者： ZHOU Shi-Qi institute of Modern statistical Mechanics Hunan University of Technology Zhuzhou 412008 China

A bridge function approximation is proposed for a single-component fluid consisting of penetrable sphere interacting via a potential that remains finite and constant for center-center distance smaller than the particle diameter and is zero otherwise. The radial distribution function from the Ornstein-Zernike integral equation combined with the present bridge function approximation is in satisfactory agreement with the corresponding simulation data for all of the investigated state points. The presently calculated excess Helmholtz free energy respectively based on virial route and compressibility route is highly self-consistent, and is in very good agreement with simulational results for the case of low temperatures. The present bridge function approximation, combined with the bridge density functional approximation, can reproduce very accurately density profiles of the penetrable sphere fluid confined in a hard spherical cavity for all the cases where simulational results are available.

关键词： complex fluids structure density profile

Ridge-Forward Quadratic Discriminant Analysis in High-Dimensional Situations

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Journal of Systems Science & Complexity 2016年第6期29卷 1703-1715页

作者： XIONG Cui ZHANG Jun LUO Xinchao School of Statistics East China Normal University College of Mathematics and Statistics Institute of Statistical SciencesShen Zhen-Hong Kong Joint Research Centre for Applied Statistical SciencesShenzhen University

Quadratic discriminant analysis is a classical and popular classification tool,but it fails to work in high-dimensional situations where the dimension p is larger than the sample size *** address this issue,the authors propose a ridge-forward quadratic discriminant(RFQD) analysis method via screening relevant predictors in a successive manner to reduce misclassification *** authors use extended Bayesian information criterion to determine the final model and prove that RFQD is selection *** Carlo simulations are conducted to examine its performance.

关键词： Extended BIC quadratic discriminant analysis ridge-forward selection consistency.

Splicing operation and fuzzy molecular automaton

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International Journal of Intelligent Computing and Cybernetics 2012年第2期5卷 206-225页

作者： Kumar S.Ray Mandrita Mondal Electronics and Communication Sciences Unit Indian Statistical InstituteKolkataIndia

Purpose–The purpose of this study is to develop a Turing machine or a finite automaton,which scans the input data tape in the form of DNA sequences and inspires the basic design of a DNA ***/methodology/approach–This model based on a splicing system can solve fuzzy reasoning autonomously by using DNA sequences and human assisted *** hardware consists of class IIS restriction enzyme and T4 DNA ligase while the software consists of double stranded DNA sequences and transition molecules which are capable of encoding fuzzy *** mixing solutions containing these components,the automaton undergoes a cascade of cleaving and splicing cycles to produce the computational result in form of double stranded DNA sequence representing automaton’s final ***–In this work,the authors have fused the idea of a splicing system with the automata theory to develop fuzzy molecular automaton in which 1,018 processors can work in parallel,requiring a trillion times less space for information storage,is 105 times faster than the existing super computer and 1,019 power operations can be performed using one Joule of ***/value–This paper presents a generalized model for biologically inspired computation in nano scale.

关键词： Splicing operation Automaton Turing