592 research outputs found

    Advances in clustering based on inter-cluster mapping

    Get PDF
    Data mining involves searching for certain patterns and facts about the structure of data within large complex datasets. Data mining can reveal valuable and interesting relationships which can improve the operations of business, health and many other disciplines. Extraction of hidden patterns and strategic knowledge from large datasets which are stored electronically, is therefore a challenge faced by many organizations. One commonly used technique in data mining for producing useful results is cluster analysis. A basic issue in cluster analysis is deciding the optimal number of clusters for a dataset. A solution to this issue is not straightforward as this form of clustering is unsupervised learning and no clear definition of cluster quality exists. In addition, this issue will be more challenging and complicated for multi-dimensional datasets. Finding the estimated number of clusters and their quality is generally based on so-called validation indexes. A limitation with typical existing validation indexes is that they only work well with specific types of datasets compatible with their design assumptions. Also their results may be inconsistent and an algorithm may need to be run multiple times to find a best estimate of the number of clusters. Furthermore, these existing approaches may not be effective for complex problems in large datasets with varied structure. To help overcome these deficiencies, an efficient and effective approach for stable estimation of the number of clusters is essential. Many clustering techniques including partitioning, hierarchal, grid-base and model-based clustering are available. Here we consider only the partitioning method e.g. the k-means clustering algorithm for analysing data. This thesis will describe a new approach for stable estimation of the number of clusters, based on use of the k-means clustering algorithm. First results obtained from the k-means clustering algorithm will be used to gain a forward and backward mapping of common elements for adjacent and non-adjacent clusters. These will be represented in the form of proportion matrices which will be used to compute combined mapped information using a matrix inner product similarity measure. This will provide indicators for the similarity of mapped elements and overlap (dissimilarity), average similarity and average overlap (average dissimilarity) between clusters. Finally, the estimated number of clusters will be decided using the maximum average similarity, minimum average overlap and coefficient of variation measure. The new approach provides more information than an application of typical existing validation indexes. For example, the new approach offers not only the estimated number of clusters but also gives an indication of fully or partially separated clusters and defines a set of stable clusters for the estimated number of clusters. The advantage of the new approach over several existing validation indexes for evaluating clustering results is demonstrated empirically by applying it on a variety of simulated and real datasets

    2-Chloro-4-(2-iodo­benzene­sulfonamido)­benzoic acid

    Get PDF
    In the title compound, C13H9ClINO4S, the dihedral angle between the aromatic rings is 81.04 (17)°. The disposition of the I and Cl atoms attached to the two rings is anti. In the crystal, mol­ecules are connected via O—H⋯O and N—H⋯O hydrogen bonds

    4-Chloro-1-iodo-2-nitro­benzene

    Get PDF
    In the mol­ecule of the title compound, C6H3ClINO2, the nitro group is disordered over two sites with occupancies of 0.506 (6) and 0.494 (6). The dihedral angles between the benzene ring and the two disordered components of the nitro group are 29.0 (2) and 51.0 (3)°. The disordering avoids short O⋯O inter­molecular contacts in the crystal

    Methyl 4-hy­droxy-2-meth­oxy­carbonyl­methyl-1,1-dioxo-1,2-dihydro-1λ6,2-benzothia­zine-3-carboxyl­ate1

    Get PDF
    There are two independent mol­ecules in the asymmetric unit of the title compound, C13H13NO7S, which have almost identical geometries. The thia­zine ring adopts a sofa conformation in both mol­ecules and the mol­ecular conformations are stabilized by intramolecular O—H⋯O hydrogen bonds. Inter­molecular C—H⋯O hydrogen bonds stabilize the crystal packing

    2-Chloro-5-(2-iodo­benzene­sulfonamido)­benzoic acid

    Get PDF
    In the mol­ecule of the title compound, C13H9ClINO4S, the coordination around the S atom is distorted tetra­hedral. The aromatic rings are oriented at a dihedral angle of 74.46 (9)°. Intra­molecular C—H⋯O hydrogen bonds result in the formation of two five- and one six-membered rings, which adopt planar, envelope and twisted conformations, respectively. In the crystal structure, inter­molecular N—H⋯O and O—H⋯O hydrogen bonds link the mol­ecules to form R 2 2(8) ring motifs, which are further linked by C—H⋯O hydrogen bonds. π–π contacts between the benzene rings [centroid–centroid distances = 3.709 (3) and 3.772 (3) Å] may further stabilize the structure. The I atom is disordered over two positions, refined with occupancies of ca 0.75 and 0.25

    Marital Adjustment And Life Satisfaction Among Early And Late Marriages

    Get PDF
    The current research focused on exploring the relationship of marital adjustment and life satisfaction among early and late marriages. Main objective of the study was to find out the effect of age on marital adjustment and life satisfaction among early and late marriages. The Dyadic Adjustment Scale (DAS) Urdu (Spanier, 1976) and Satisfaction with Life Scale (SWLS) (Diener, Emmons, Larsen & Griffin, 1985) were used to measure the phenomenon of marital adjustment and life satisfaction. The sample was comprised of (N=160) early and late married, men and women. Early married (n=80) and late married (n=80) selected from different cities of Punjab, Pakistan. Pearson Product Moment Correlation and t-test were used for statistical analysis. Results indicate a significant positive correlation (r= .33, significant at p .01) in marital adjustment and life satisfaction. On the other hand there is a significant difference (significant at p .001) between late marriages and early marriages on marital adjustment. The results also indicate that there is a significant difference (significant at p .001) between late marriages and early marriages on life satisfaction. Key Words: Marital adjustment, life satisfaction, early married, late marrie

    2-Bromo-4-nitro­aniline

    Get PDF
    In the mol­ecule of the title compound, C6H5BrN2O2, the dihedral angle between the nitro group and the aromatic ring is 4.57 (4)°. An intra­molecular N—H⋯Br inter­action results in the formation of a planar five-membered ring, which is oriented with respect to the aromatic ring at a dihedral angle of 1.64 (6)°. In the crystal structure, inter­molecular N—H⋯N and N—H⋯O hydrogen bonds link the mol­ecules

    Kanak - kanak didedahkan pertanian mesra alam

    Get PDF
    Effective energy consumption prediction is important for determining the demand and supply of energy. The challenge is how to predict energy consumption? This study presents an energy consumption analytical regression model and process based on the project conducted in an Australian company. This study involved the analysis of household and energy consumption datasets in the residential sector. The analytical model generation process is organised into four major stages: prepared the household and energy consumption data or data cleansing, household energy consumption clustering (segmentation or groups) using k-means clustering algorithm for similarity measure in their characteristics, stepwise multiple regression for variables selection to determine the final model's predictors, and filter the final regression model to identify the influential observations using Cook's distance and Q-Q (quantile-quantile) normal plot for improvement in the model. The final filtered regression model represents 64 percent variation to the dependent variable is explained by independent variables with correlation 0.8 between energy consumption observed and predicted values. The abovementioned process and resultant regression model seem useful for developing household energy consumptions models for managing the demand and supply of energy

    Methyl 4-hy­droxy-2-isopropyl-1,1-dioxo-2H-1,2-benzothia­zine-3-carboxyl­ate

    Get PDF
    In the crystal structure of the title mol­ecule, C13H15NO5S, the S and N atoms of the thia­zine ring exihibit the maximum deviations from the least-squares plane of 0.3008 (6) and 0.3280 (7) Å, respectively. The ring therefore adopts a half chair conformation. The thia­zine ring is twisted by an angle of 13.29 (7)° with respect to the aromatic ring. The isopropyl substituent is oriented at a dihedral angle of 53.2 (12)° with respect to the thia­zine ring. An intra­molecular O—H⋯O hydrogen bond occurs. Inter­molecular hydrogen bonding is observed in the crystal structure
    corecore