Results 211 to 220 of about 920,909 (261)
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DENSITY AS AN INDEX OF THE EFFECTS OF ESTROGENS ON BONE
Endocrinology, 1956THE discovery that the proliferation of medullary bone paralleled the follicular phase of the ovarian cycle in pigeons by Kyes and Potter (1) led to extensive studies on the effects of estrogenic materials in various birds and mammals. Zondek (2) using domestic fowl, Pfeiffer and Gardner (3) using English Sparrows and Gardner and Pfeiffer (4) using ...
D W, CALHOUN, R A, EDGREN
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A spin-density polarization index
The Journal of Chemical Physics, 1998By analogy with the Carbo overlaplike similarity measure, a spin-density polarization index (SPI) is defined. This index gives the Euclidean distance between the α and β electron densities for an open-shell molecule. An extensive study of the O2 molecule reveals that the SPI is highly dependent on the theoretical method, but is less sensitive to the ...
S. Kent Worsnop +3 more
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Estimating the global density of graphs by a sparseness index
Applied Mathematics and Computation, 2013Computation of sparse matrix is key in a wide range of applications of science and engineering. Matrix is tightly bound to the graph data structure and frequently used as an effective alternative: the complexity of fairly complicated operations on graphs can be measured as the computer time required to execute a number of arithmetic operations on ...
Salvatore Menniti +2 more
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Density index and proximity search in large graphs
Proceedings of the 21st ACM international conference on Information and knowledge management, 2012Given a large real-world graph where vertices are associated with labels, how do we quickly find interesting vertex sets according to a given query? In this paper, we study label-based proximity search in large graphs, which finds the top-k query-covering vertex sets with the smallest diameters. Each set has to cover all the labels in a query. Existing
Nan Li +3 more
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Validity index for clusters of different sizes and densities
Pattern Recognition Letters, 2011Cluster validity indices are used to validate results of clustering and to find a set of clusters that best fits natural partitions for given data set. Most of the previous validity indices have been considerably dependent on the number of data objects in clusters, on cluster centroids and on average values.
Krista Rizman Zalik, Borut Zalik
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Generalization of the Population Density Index Model
Perceptual and Motor Skills, 1991The author's population density index (PDI) model was previously derived for the measurement of population density in studies employing 100 density points or less. The PDI model is now generalized through a derived equation which allows its basic component, the unit lattice average Euclidean distance, to be calculated for any finite lattice rectangle ...
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STATISTICAL INFERENCE FOR THE POPULATION DENSITY INDEX
Perceptual and Motor Skills, 1992A procedure is provided to calculate the probability of the population density index under the null hypothesis of random distribution of points on a k by k square area.
Paul W. Mielke, Kenneth J. Berry
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Spectral Index–Flux Density Relation for Quasars
Nature, 1970THE relation between the mean spectral indices α of extragalactic radio sources and their flux densities S(S∼v−a) at a frequency of 178 MHz has been obtained from data on the flux densities of all radio sources from the revised 3C catalogue at galactic latitudes |b| ≥ 10° at four frequencies: 86, 178, 750 and 1,400 MHz, measured by the P. N.
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Drainage Density as Index of Watershed Development
Journal of the Irrigation and Drainage Division, 1978Studies have been completed on watersheds in Florida, and a methodology developed to predict environmental impacts using drainage characteristics of developing watersheds. The drainage density index, a measure of total length of waterways observed on aerial photographs per unit area, was computed for various watersheds in order to relate land-use ...
Philip B. Bedient +2 more
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A Density Discriminant Index for Cluster Validation
2019 11th International Conference on Information Technology and Electrical Engineering (ICITEE), 2019Clustering analysis is widely applied in several domains of study. Using a suitable number of clusters is one of the most important factors to influence the performance of clustering. Several algorithms of cluster validation have been developed to find such a number.
Supphawarich Thanarattananakin +2 more
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