Articles de revues : « Hierarchical and complete parametrizations »

1

Rohan, Eduard, Jana Camprová Turjanicová et Václav Liška. « Geometrical model of lobular structure and its importance for the liver perfusion analysis ». PLOS ONE 16, n^o 12 (2 décembre 2021) : e0260068. http://dx.doi.org/10.1371/journal.pone.0260068.

Texte intégral

Résumé :

A convenient geometrical description of the microvascular network is necessary for computationally efficient mathematical modelling of liver perfusion, metabolic and other physiological processes. The tissue models currently used are based on the generally accepted schematic structure of the parenchyma at the lobular level, assuming its perfect regular structure and geometrical symmetries. Hepatic lobule, portal lobule, or liver acinus are considered usually as autonomous functional units on which particular physiological problems are studied. We propose a new periodic unit—the liver representative periodic cell (LRPC) and establish its geometrical parametrization. The LRPC is constituted by two portal lobulae, such that it contains the liver acinus as a substructure. As a remarkable advantage over the classical phenomenological modelling approaches, the LRPC enables for multiscale modelling based on the periodic homogenization method. Derived macroscopic equations involve so called effective medium parameters, such as the tissue permeability, which reflect the LRPC geometry. In this way, mutual influences between the macroscopic phenomena, such as inhomogeneous perfusion, and the local processes relevant to the lobular (mesoscopic) level are respected. The LRPC based model is intended for its use within a complete hierarchical model of the whole liver. Using the Double-permeability Darcy model obtained by the homogenization, we illustrate the usefulness of the LRPC based modelling to describe the blood perfusion in the parenchyma.

Styles APA, Harvard, Vancouver, ISO, etc.

2

Muir, Jack B., et Hrvoje Tkalčić. « Probabilistic lowermost mantle P-wave tomography from hierarchical Hamiltonian Monte Carlo and model parametrization cross-validation ». Geophysical Journal International 223, n^o 3 (15 septembre 2020) : 1630–43. http://dx.doi.org/10.1093/gji/ggaa397.

Texte intégral

Résumé :

SUMMARY Bayesian methods, powered by Markov Chain Monte Carlo estimates of posterior densities, have become a cornerstone of geophysical inverse theory. These methods have special relevance to the deep Earth, where data are sparse and uncertainties are large. We present a strategy for efficiently solving hierarchical Bayesian geophysical inverse problems for fixed parametrizations using Hamiltonian Monte Carlo sampling, and highlight an effective methodology for determining optimal parametrizations from a set of candidates by using efficient approximations to leave-one-out cross-validation for model complexity. To illustrate these methods, we use a case study of differential traveltime tomography of the lowermost mantle, using short period P-wave data carefully selected to minimize the contributions of the upper mantle and inner core. The resulting tomographic image of the lowermost mantle has a relatively weak degree 2—instead there is substantial heterogeneity at all low spherical harmonic degrees less than 15. This result further reinforces the dichotomy in the lowermost mantle between relatively simple degree 2 dominated long-period S-wave tomographic models, and more complex short-period P-wave tomographic models.

Styles APA, Harvard, Vancouver, ISO, etc.

3

Castro, Ildefonso, Ildefonso Castro-Infantes et Jesús Castro-Infantes. « Curves in the Lorentz-Minkowski plane : elasticae, catenaries and grim-reapers ». Open Mathematics 16, n^o 1 (17 juillet 2018) : 747–66. http://dx.doi.org/10.1515/math-2018-0069.

Texte intégral

Résumé :

AbstractThis article is motivated by a problem posed by David A. Singer in 1999 and by the classical Euler elastic curves. We study spacelike and timelike curves in the Lorentz-Minkowski plane 𝕃2 whose curvature is expressed in terms of the Lorentzian pseudodistance to fixed geodesics. In this way, we get a complete description of all the elastic curves in 𝕃2 and provide the Lorentzian versions of catenaries and grim-reaper curves. We show several uniqueness results for them in terms of their geometric linear momentum. In addition, we are able to get arc-length parametrizations of all the aforementioned curves and they are depicted graphically.

Styles APA, Harvard, Vancouver, ISO, etc.

4

Ha, Seung-Yeal, et Zhuchun Li. « Complete synchronization of Kuramoto oscillators with hierarchical leadership ». Communications in Mathematical Sciences 12, n^o 3 (2014) : 485–508. http://dx.doi.org/10.4310/cms.2014.v12.n3.a5.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

5

SEGEV, RE'EM. « Hierarchical Consequentialism ». Utilitas 22, n^o 3 (30 juillet 2010) : 309–30. http://dx.doi.org/10.1017/s0953820810000221.

Texte intégral

Résumé :

The article considers a hierarchical theory that combines concern for two values: individual well-being – as a fundamental, first-order value – and (distributive) fairness – as a high-order value whose exclusive function is to complete the value of individual well-being by resolving internal clashes within it that occur in interpersonal conflicts. The argument for this unique conception of high-order fairness is that fairness is morally significant in itself only regarding what matters – individual well-being – and when it matters – in interpersonal conflicts in which constitutive aspects of individual well-being clash. Consequently, the proposed theory is not exposed to the claim that fairness comes at the expense of welfare. This theory is considered within a consequential framework, based on the standard version and, alternatively, on a novel interpretation of consequentialism. Thus, it refutes the claim that consequentialism does not take the distinction between persons seriously.

Styles APA, Harvard, Vancouver, ISO, etc.

6

Syafiyah, Umi, Dita Putri Puspitasari, Iqbal Asrafi, Brian Wicaksono et Finer Mayland Sirait. « Analisis Perbandingan Hierarchical dan Non-Hierarchical Clustering Pada Data Indikator Ketenagakerjaan di Jawa Barat Tahun 2020 ». Seminar Nasional Official Statistics 2022, n^o 1 (1 novembre 2022) : 803–12. http://dx.doi.org/10.34123/semnasoffstat.v2022i1.1221.

Texte intégral

Résumé :

Pandemi Covid-19 telah memberikan dampak yang signifikan terhadap berbagai sektor di Indonesia, termasuk Provinsi Jawa Barat. Salah satu sektor yang terdampak adalah sektor ketenagakerjaan. Provinsi Jawa Barat merupakan provinsi dengan Tingkat Pengangguran Terbuka (TPT) tertinggi di Indonesia, setelah Provinsi Banten. Hal ini disebabkan oleh meningkatnya angkatan kerja tetapi tidak imbangi dengan kesempatan kerja yang memadai. Tujuan dari penelitian ini adalah mengelompokkan kabupaten/kota di Provinsi Jawa Barat berdasarkan indikator ketenagakerjaan. Selain itu, penelitian ini juga bertujuan menyajikan perbandingan antara metode klaster hierarki, yaitu single linkage, average linkage, dan complete linkage, dan metode klaster non hierarki, yaitu k-means cluster. Hasil analisis menunjukkan bahwa metode complete linkage 2 klaster adalah metode yang paling cocok dalam pengelompokkan kabupaten/kota di Provinsi Jawa Barat berdasarkan indikator ketenagakerjaan. Terdapat dua kelompok yang terbentuk berdasarkan complete linkage, yaitu: klaster 1 yang beranggotakan 18 kabupaten/kota dengan karakteristik perkembangan tenaga kerja yang sudah baik dan klaster 2 yang beranggotakan 9 kabupaten/kota merupakan kluster dengan karakteristik perkembangan tenaga yang belum maksimal.

Styles APA, Harvard, Vancouver, ISO, etc.

7

Chen, Chien-Ming, Xinying Zheng et Tsu-Yang Wu. « A Complete Hierarchical Key Management Scheme for Heterogeneous Wireless Sensor Networks ». Scientific World Journal 2014 (2014) : 1–13. http://dx.doi.org/10.1155/2014/816549.

Texte intégral

Résumé :

Heterogeneous cluster-based wireless sensor networks (WSN) attracted increasing attention recently. Obviously, the clustering makes the entire networks hierarchical; thus, several kinds of keys are required for hierarchical network topology. However, most existing key management schemes for it place more emphasis on pairwise key management schemes or key predistribution schemes and neglect the property of hierarchy. In this paper, we propose a complete hierarchical key management scheme which only utilizes symmetric cryptographic algorithms and low cost operations for heterogeneous cluster-based WSN. Our scheme considers four kinds of keys, which are an individual key, a cluster key, a master key, and pairwise keys, for each sensor node. Finally, the analysis and experiments demonstrate that the proposed scheme is secure and efficient; thus, it is suitable for heterogeneous cluster-based WSN.

Styles APA, Harvard, Vancouver, ISO, etc.

8

Beem, John K., et Paul E. Ehrlich. « Geodesic completeness and stability ». Mathematical Proceedings of the Cambridge Philosophical Society 102, n^o 2 (septembre 1987) : 319–28. http://dx.doi.org/10.1017/s0305004100067347.

Texte intégral

Résumé :

A (connected) Riemannian manifold M is geodesically complete (i.e. each geodesic may be extended to a geodesic with domain ( −∞, + ∞)) iff, as a metric space under the induced Riemannian distance function, M is Cauchy complete ([12], p. 138). Furthermore, all compact Riemannian manifolds are complete. On the other hand, compact pseudo-Riemannian manifolds exist which are not geodesically complete. For example Fierz and Jost[8] have constructed incomplete metrics of the form 2dx dy + h dy2 on T2. Furthermore, Williams [16] has shown that geodesic completeness may fail to be stable for pseudo-Riemannian manifolds. Here a property is said to be stable if the set of metrics for M with this property is open. This failure of stability may occur for both compact and non-compact manifolds. In particular, Williams has found that M = S1 x S1 = ℝ/(2πZ x 2πZ), which may be given the complete Lorentzian metric g = 2dx dy, also admits Lorentzian metrics gn = 2dx dy+(sin(x)/n) dy2 which are geodesically incomplete yet which for large n are arbitrarily close to g in the Whitney fine Cr topologies. In this example the set S = {(0, y)|0 ≤ y ≤ 2π} represents the image of a closed null geodesic for (M, g) and also for all (M, gn). However, for the metrics (M, gn) this closed null geodesic has affine parametrizations which are incomplete because the velocity vector of this null geodesic returns to a scalar multiple of itself after each complete circuit of S. In general, a closed null geodesic will be complete iff its velocity vector returns exactly to itself after each trip around its image.

Styles APA, Harvard, Vancouver, ISO, etc.

9

Longford, Nicholas T. « Hierarchical Models and Social Sciences ». Journal of Educational and Behavioral Statistics 20, n^o 2 (juin 1995) : 205–9. http://dx.doi.org/10.3102/10769986020002205.

Texte intégral

Résumé :

The view is presented that multilevel methods are just one element in a hypothetical complete analysis of observational data on human subjects. In most contexts several sources of uncertainty, in addition to those captured by a multilevel analysis, are present, and so the confidence placed in the results of a typical multilevel analysis is unrealistically optimistic. A “soft-ware-free” analysis of longitudinal data with rectangular design is outlined. Questions posed by the National Center for Education Statistics and elaborated by de Leeuw and Kreft are briefly discussed.

Styles APA, Harvard, Vancouver, ISO, etc.

10

Fummi, F., et D. Sciuto. « A complete testing strategy based on interacting and hierarchical FSMs ». Integration 23, n^o 1 (octobre 1997) : 75–93. http://dx.doi.org/10.1016/s0167-9260(97)00015-1.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

11

Dennis, Robin L., Donna B. Schwede, Jesse O. Bash, Jon E. Pleim, John T. Walker et Kristen M. Foley. « Sensitivity of continental United States atmospheric budgets of oxidized and reduced nitrogen to dry deposition parametrizations ». Philosophical Transactions of the Royal Society B : Biological Sciences 368, n^o 1621 (5 juillet 2013) : 20130124. http://dx.doi.org/10.1098/rstb.2013.0124.

Texte intégral

Résumé :

Reactive nitrogen (N r ) is removed by surface fluxes (air–surface exchange) and wet deposition. The chemistry and physics of the atmosphere result in a complicated system in which competing chemical sources and sinks exist and impact that removal. Therefore, uncertainties are best examined with complete regional chemical transport models that simulate these feedbacks. We analysed several uncertainties in regional air quality model resistance analogue representations of air–surface exchange for unidirectional and bi-directional fluxes and their effect on the continental N r budget. Model sensitivity tests of key parameters in dry deposition formulations showed that uncertainty estimates of continental total nitrogen deposition are surprisingly small, 5 per cent or less, owing to feedbacks in the chemistry and rebalancing among removal pathways. The largest uncertainties (5%) occur with the change from a unidirectional to a bi-directional NH 3 formulation followed by uncertainties in bi-directional compensation points (1–4%) and unidirectional aerodynamic resistance (2%). Uncertainties have a greater effect at the local scale. Between unidirectional and bi-directional formulations, single grid cell changes can be up to 50 per cent, whereas 84 per cent of the cells have changes less than 30 per cent. For uncertainties within either formulation, single grid cell change can be up to 20 per cent, but for 90 per cent of the cells changes are less than 10 per cent.

Styles APA, Harvard, Vancouver, ISO, etc.

12

Del Valle Erkiaga, Ikerne, et Kepa Astorkiza Ikazuriaga. « Clustering Basque fishing communities ». Studies of Applied Economics 37, n^o 3 (9 octobre 2019) : 60. http://dx.doi.org/10.25115/eea.v37i3.2773.

Texte intégral

Résumé :

The main objective of this paper is to identify the taxonomy of Basque local fishing communities (FC) using a set of either, hierarchical (i.e. Ward, average and complete linkage), non-hierarchical (i.e. k-means and k-medoids) and mixed hierarchical-kmeans clustering algorithms; and two alternative fishing related variates at fishing community level, {

Styles APA, Harvard, Vancouver, ISO, etc.

13

Rausch, Johannes, Octavio Martinez, Fabian Bissig, Ce Zhang et Stefan Feuerriegel. « DocParser : Hierarchical Document Structure Parsing from Renderings ». Proceedings of the AAAI Conference on Artificial Intelligence 35, n^o 5 (18 mai 2021) : 4328–38. http://dx.doi.org/10.1609/aaai.v35i5.16558.

Texte intégral

Résumé :

Translating renderings (e. g. PDFs, scans) into hierarchical document structures is extensively demanded in the daily routines of many real-world applications. However, a holistic, principled approach to inferring the complete hierarchical structure in documents is missing. As a remedy, we developed “DocParser”: an end-to-end system for parsing complete document structure – including all text elements, nested figures, tables, and table cell structures. Our second contribution is to provide a dataset for evaluating hierarchical document structure parsing. Our third contribution is to propose a scalable learning framework for settings where domain-specific data are scarce, which we address by a novel approach to weak supervision that significantly improves the document structure parsing performance. Our experiments confirm the effectiveness of our proposed weak supervision: Compared to the baseline without weak supervision, it improves the mean average precision for detecting document entities by 39.1% and improves the F1 score of classifying hierarchical relations by 35.8%.

Styles APA, Harvard, Vancouver, ISO, etc.

14

Tudor, M. « A test of numerical instability and stiffness in the parametrizations of the ARPÉGE and ALADIN models ». Geoscientific Model Development Discussions 5, n^o 4 (11 décembre 2012) : 4233–68. http://dx.doi.org/10.5194/gmdd-5-4233-2012.

Texte intégral

Résumé :

Abstract. Meteorological numerical weather prediction (NWP) models solve a system of partial differential equations in time and space. Semi-lagrangian advection scheme in the model dynamics allows for long time-steps. These longer time-steps can result in instabilities occurring in the model physics. A system of differential equations in which some solution components decay more rapidly than others is stiff. In this case it is stability rather than accuracy that restricts the time-step. The vertical diffusion parametrization can cause fast non-meteorological oscillations around the slowly evolving true solution (fibrillations). These are treated with an anti-fibrillation scheme. But small oscillations remain in an operational weather forecasts using ARPÉGE and ALADIN models. It is needed to test of the complete model formulation, as implemented in the operational forecast. In this paper, a simple test is designed. The test reveals if the formulation of particular physical parametrization is a stiff problem or potentially numerically unstable in combination with any other part of the model. When the test is applied to a stable scheme, the solution remains stable. But, applying the test to a potentially unstable scheme yields a solution with fibrillations of substantial amplitude. The parametrizations of a NWP model ARPÉGE were tested one by one to see which one may be the source of unstable model behaviour. The test has identified the stratiform precipitation scheme (a diagnostic Kessler type scheme) as a stiff problem, particularly the term that describes the evaporation of snow.

Styles APA, Harvard, Vancouver, ISO, etc.

15

Reshetnyak, Yuri G. « On the Stability in Bonnet's Theorem of the Surface Theory ». gmj 14, n^o 3 (septembre 2007) : 543–64. http://dx.doi.org/10.1515/gmj.2007.543.

Texte intégral

Résumé :

Abstract In the space , 𝑛-dimensional surfaces are considered having the parametrizations which are functions of the Sobolev class with 𝑝 > 𝑛. The first and the second fundamental tensor are defined. The Peterson–Codazzi equations for such functions are understood in some generalized sense. It is proved that if the first and the second fundamental tensor of one surface are close to the first and, respectively, to the second fundamental tensor of the other surface, then these surfaces will be close up to the motion of the space . A difference between the fundamental tensors and the nearness of the surfaces are measured with the help of suitable 𝑊-norms. The proofs are based on a generalization of Frobenius' theorem about completely integrable systems of the differential equations which was proved by Yu. E. Borovskiĭ. The integral representations of functions by differential operators with complete integrability condition are used, which were elaborated by the author in his other works.

Styles APA, Harvard, Vancouver, ISO, etc.

16

Komar, Yuriy, Rostyslav Dubas et Alexey Ivanov. « Conceptual model of complete creative management formation of complete human health ». Problems of Innovation and Investment Development, n^o 21 (27 décembre 2019) : 86–96. http://dx.doi.org/10.33813/2224-1213.21.2019.10.

Texte intégral

Résumé :

The purpose of the study is to substantiate and develop a Conceptual model of full-fledged creative management of the formation of complete human health. The authors summarized the theoretical generalization of the category «full human health» (FHH) showed that its essence is a complete system of universal human five-element subsystems of different nature, consisting of five levels, ten species and fifty elements of human health intended for use in any public environment. Methodology. The theoretical and methodological basis of the study is the attributive (triple) scientific approach, the method of modeling systems of complete creative management, the method of structural-linguistic quantification in a complex combination with the fundamental principles of human health: fullness, well-being and hierarchy. The aforementioned theoretical and methodological base of the research made it possible to create, in the format of the Fundamental Model of Full-fledged Creative Management of the Life of Ukrainian Society, a Conceptual Model of Full-fledged Creative Management of the Formation of FHH, to characterize its phases, stages of management, to show the role of the subject of management – the person in the formation of FHH and to draw appropriate scientific conclusions. The scientific novelty of the obtained results lies in the creation of the Conceptual model of complete creative management of FHH as a universal full-fledged model of creative management in the composition of four horizontal phases and ten vertical stages of control, in which the set of five-element common human systems of different hierarchical level and nature on five levels, ten species and fifty elements of the process of forming a FHH for its use in any society nomu environment. Conclusions. The unique properties of the conceptual model of full-fledged creative management characterize it as a modern all-human, full-fledged system of creative management of higher-level hierarchical puzzle. This necessitates the widespread use of the Conceptual Model in the basic spheres of human activity for the full management of his health in the conditions of any social environment, in particular Ukrainian society.

Styles APA, Harvard, Vancouver, ISO, etc.

17

Zhang, Shanwen, Harry Wang et Wenzhun Huang. « Palmprint identification combining hierarchical multi-scale complete LBP and weighted SRC ». Soft Computing 24, n^o 6 (17 juillet 2019) : 4041–53. http://dx.doi.org/10.1007/s00500-019-04172-3.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

18

Owais, Mahmoud, et Mostafa K. Osman. « Complete hierarchical multi-objective genetic algorithm for transit network design problem ». Expert Systems with Applications 114 (décembre 2018) : 143–54. http://dx.doi.org/10.1016/j.eswa.2018.07.033.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

19

Greenlaw, Raymond, et Sanpawat Kantabutra. « On the parallel complexity of hierarchical clustering and CC-complete problems ». Complexity 14, n^o 2 (novembre 2008) : 18–28. http://dx.doi.org/10.1002/cplx.20238.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

20

Grumitt, R. D. P., Luke R. P. Jew et C. Dickinson. « Hierarchical Bayesian CMB component separation with the No-U-Turn Sampler ». Monthly Notices of the Royal Astronomical Society 496, n^o 4 (26 juin 2020) : 4383–401. http://dx.doi.org/10.1093/mnras/staa1857.

Texte intégral

Résumé :

ABSTRACT In this paper, we present a novel implementation of Bayesian cosmic microwave background (CMB) component separation. We sample from the full posterior distribution using the No-U-Turn Sampler (NUTS), a gradient-based sampling algorithm. Alongside this, we introduce new foreground modelling approaches. We use the mean shift algorithm to define regions on the sky, clustering according to naively estimated foreground spectral parameters. Over these regions we adopt a complete pooling model, where we assume constant spectral parameters, and a hierarchical model, where we model individual pixel spectral parameters as being drawn from underlying hyperdistributions. We validate the algorithm against simulations of the LiteBIRD and C-Band All-Sky Survey (C-BASS) experiments, with an input tensor-to-scalar ratio of r = 5 × 10−3. Considering multipoles 30 ≤ ℓ < 180, we are able to recover estimates for r. With LiteBIRD-only observations, and using the complete pooling model, we recover r = (12.9 ± 1.4) × 10−3. For C-BASS and LiteBIRD observations we find r = (9.0 ± 1.1) × 10−3 using the complete pooling model, and r = (5.2 ± 1.0) × 10−3 using the hierarchical model. Unlike the complete pooling model, the hierarchical model captures pixel-scale spatial variations in the foreground spectral parameters, and therefore produces cosmological parameter estimates with reduced bias, without inflating their uncertainties. Measured by the rate of effective sample generation, NUTS offers performance improvements of ∼103 over using Metropolis–Hastings to fit the complete pooling model. The efficiency of NUTS allows us to fit the more sophisticated hierarchical foreground model that would likely be intractable with non-gradient-based sampling algorithms.

Styles APA, Harvard, Vancouver, ISO, etc.

21

Commons, Michael Lamport, et Chester Arnold Wolfsont. « A complete theory of empathy must consider stage changes ». Behavioral and Brain Sciences 25, n^o 1 (février 2002) : 30–31. http://dx.doi.org/10.1017/s0140525x02320016.

Texte intégral

Résumé :

A sequential, hierarchical stage model of empathy can account for a comprehensive range of empathic behaviors. We provide an illustrative table, “Stages of Empathy,” to demonstrate how increasingly complex empathic behaviors emerge at each stage, beginning with the infant's “automatic empathy” and ending with the advanced adult's “coconstruction of empathetic reality.”

Styles APA, Harvard, Vancouver, ISO, etc.

22

DONNER, REIK, FRED FEUDEL, NORBERT SEEHAFER et MIGUEL A. F. SANJUÁN. « HIERARCHICAL MODELING OF A FORCED ROBERTS DYNAMO ». International Journal of Bifurcation and Chaos 17, n^o 10 (octobre 2007) : 3589–93. http://dx.doi.org/10.1142/s021812740701941x.

Texte intégral

Résumé :

We investigate the dynamo effect in a flow configuration introduced by G. O. Roberts in 1972. Based on a clear energetic hierarchy of Fourier components on the steady-state dynamo branch, an approximate model of interacting modes is constructed covering all essential features of the complete system but allowing simulations with a minimum amount of computation time. We use this model to study the excitation mechanism of the dynamo, the transition from stationary to time-dependent dynamo solutions and the characteristic properties of the latter ones.

Styles APA, Harvard, Vancouver, ISO, etc.

23

Haeseler, Fritz V., Heinz-Otto Peitgen et Gencho Skordev. « Pascal's triangle, dynamical systems and attractors ». Ergodic Theory and Dynamical Systems 12, n^o 3 (septembre 1992) : 479–86. http://dx.doi.org/10.1017/s0143385700006908.

Texte intégral

Résumé :

AbstractThis paper establishes a global dynamical systems approach for the fractal patterns which are obtained when analysing the divisibility of binomial coefficients modulo a prime power. The general framework is within the class of hierarchical iterated function systems. As a consequence we obtain a complete deciphering of the hierarchical self-similarity features.

Styles APA, Harvard, Vancouver, ISO, etc.

24

Mendonça, Bruno, et Ruy Tojeiro. « Umbilical Submanifolds of Sn × R ». Canadian Journal of Mathematics 66, n^o 2 (1 avril 2014) : 400–428. http://dx.doi.org/10.4153/cjm-2013-003-3.

Texte intégral

Résumé :

AbstractWe give a complete classification of umbilical submanifolds of arbitrary dimension and codimension of ×ℝ, extending the classification of umbilical surfaces in ×ℝ by Souam and Toubiana as well as the local description of umbilical hypersurfaces in × ℝ by Van der Veken and Vrancken. We prove that, besides small spheres in a slice, up to isometries of the ambient space they come in a two-parameter family of rotational submanifolds whose substantial codimension is either one or two and whose profile is a curve in a totally geodesic ×ℝ or ×ℝ, respectively, the former case arising in a one-parameter family. All of them are diffeomorphic to a sphere, except for a single element that is diffeomorphic to Euclidean space. We obtain explicit parametrizations of all such submanifolds. We also study more general classes of submanifolds of × R and ℍn × ℝ. In particular, we give a complete description of all submanifolds in those product spaces for which the tangent component of a unit vector field spanning the factor ℝ is an eigenvector of all shape operators. We show that surfaces with parallel mean curvature vector in ×ℝ and ℍn×ℝ having this property are rotational surfaces, and use this fact to improve some recent results by Alencar, do Carmo, and Tribuzy. We also obtain a Dajczer-type reduction of codimension theorem for submanifolds of × ℝ and ℍn × ℝ.

Styles APA, Harvard, Vancouver, ISO, etc.

25

Nascimento, Emanuela Rodrigues do, Mácio Augusto de Albuquerque, Kleber Napoleão Nunes de Oliveira Barros et Patrícia Silva Nascimento Barros. « Cluster analysis applied to the Human Development Index (HDI) of Brazilian States ». Research, Society and Development 11, n^o 2 (24 janvier 2022) : e18011225747. http://dx.doi.org/10.33448/rsd-v11i2.25747.

Texte intégral

Résumé :

This study aims to compare the performance of each method (hierarchical and non-hierarchical) of the grouping formed by several HDI from the 27 brazilian states, through the cluster analysis technique. As well as determining how many states there are in each formed group, to thus specify which technique best represents the data. Data from Atlas Brasil 2013 were used in relation to the 2010 HDI. For cluster analysis, the Mahalanobins matrix was used with the hierarchical method, from the data obtained, we applied the simple linkage methods, complete, average, ward liaison and a non-hierarchical method through the K-means method, the conphenetic correlation coefficient was also applied to measure the degree of fit between the original similar matrices and the resulting matrix of simplification provided by the grouping method. However, the method that best represents the data was the complete link. When grouping the states, the similarity between the HDI-R, HDI-L and HDI-S variables was considered this relationship formed similar groups between the connections from different regions of Brazil.

Styles APA, Harvard, Vancouver, ISO, etc.

26

JIA, WEIJIA, et ZHIBIN SUN. « ON COMPUTATIONAL COMPLEXITY OF HIERARCHICAL OPTIMIZATION ». International Journal of Foundations of Computer Science 13, n^o 05 (octobre 2002) : 667–70. http://dx.doi.org/10.1142/s0129054102001369.

Texte intégral

Résumé :

In this work, the computational complexity of a hierarchic optimization problem involving in several players is studied. Each player is assigned with a linear objective function. The set of variables is partitioned such that each subset corresponds to one player as its decision variables. All the players jointly make a decision on the values of these variables such that a set of linear constraints should be satisfied. One special player, called the leader, makes decision on its decision variables before of all the other players. The rest, after learnt of the decision of the leader, make their choices so that their decisions form a Nash Equilibrium for them, breaking tie by maximizing the objective function of player. We show that the exact complexity of the problem is FPNP-complete.

Styles APA, Harvard, Vancouver, ISO, etc.

27

Zhou, Xi Yi, Ge Zhang et Li Qiang Liu. « Hierarchical Mobile IPv6 Based Handoff Optimization Scheme ». Advanced Materials Research 798-799 (septembre 2013) : 460–63. http://dx.doi.org/10.4028/www.scientific.net/amr.798-799.460.

Texte intégral

Résumé :

Hierarchical mobile IPv6 fastens the binding update process of micro mobile handoff and reduces handoff delay. A large number of binding updates and registrations increase signaling load and lengthen handoff delay. For this reason, it is proposed to apply tunneling mechanism to hierarchical mobile IPv6 optimization scheme (T-HMIPv6) to obtain care-of address in advance based on handoff information, conduct duplicate address detection, and complete local binding update while building a tunnel. Simulation experiments show that compared with hierarchical mobile IPv6, this scheme can greatly reduce handoff delay and packet loss rate and effectively improve mobile node's macro handoff performance.

Styles APA, Harvard, Vancouver, ISO, etc.

28

Gensheimer, Michael F., Douglas S. Hawkins, Ralph P. Ermoian et Andrew D. Trister. « Assessing the scale of tumor heterogeneity by complete hierarchical segmentation of MRI ». Physics in Medicine and Biology 60, n^o 3 (9 janvier 2015) : 977–93. http://dx.doi.org/10.1088/0031-9155/60/3/977.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

29

Wang, Jin, Qidong Zhang, Kui Ren et Zhensu She. « Multi-scaling hierarchical structure analysis on the sequence ofE. coli complete genome ». Chinese Science Bulletin 46, n^o 23 (décembre 2001) : 1988–91. http://dx.doi.org/10.1007/bf02901913.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

30

He, Cheng, et Li Li. « Hierarchical optimization on an unbounded parallel-batching machine ». RAIRO - Operations Research 52, n^o 1 (janvier 2018) : 55–60. http://dx.doi.org/10.1051/ro/2017089.

Texte intégral

Résumé :

This paper studies a hierarchical optimization problem on an unbounded parallel-batching machine, in which two objective functions are maximum costs, representing different purposes of two decision-makers. By a hierarchical optimization problem, we mean the problem of optimizing the secondary criterion under the constraint that the primary criterion is optimized. A parallel-batching machine is a machine that can handle several jobs in a batch in which all jobs start and complete respectively at the same time. We present an O(n4)-time algorithm for this hierarchical scheduling problem.

Styles APA, Harvard, Vancouver, ISO, etc.

31

Fernández, Luis, Juan Ortega et Adriel Sosa. « Parametrization of the NRTL Model with a Multiobjective Approach : Implications in the Process Simulation ». Thermo 2, n^o 3 (31 août 2022) : 267–88. http://dx.doi.org/10.3390/thermo2030019.

Texte intégral

Résumé :

Thermodynamics, as a scientific tool, advises on the control of variables involved in processes of different nature and is particularly useful in the design of equipment, or to obtain previous simulations. However, to generate more accurate models, an exact science is required. Thus, the thermodynamic–mathematical binomial is able to relate the fundamental variables of a system using the potential functions directing the process, although these relationships are not always completely satisfactory, as it is necessary to complete the modelling with a set of parameters, which depend on the experimentation. To ensure a better description of the behavior of a system, in this work a multi-objective optimization procedure (MOP) is applied to the NRTL model, comparing the results with other conventional procedures used to characterize the real properties of the binary methyl methanoate + pentane. The results obtained with the MOP confirmed a better representation of the experimental information with NRTL, analyzing its impact on the simulation/design processes. The set of optimal parametrizations obtained allow several options to be process engineered to select the most appropriate one depending on the specific problem to be designed.

Styles APA, Harvard, Vancouver, ISO, etc.

32

Mares, Constantin, Ileana Mares, Venera Dobrica et Crisan Demetrescu. « Quantification of the Direct Solar Impact on Some Components of the Hydro-Climatic System ». Entropy 23, n^o 6 (31 mai 2021) : 691. http://dx.doi.org/10.3390/e23060691.

Texte intégral

Résumé :

This study addresses the causal links between external factors and the main hydro-climatic variables by using a chain of methods to unravel the complexity of the direct sun–climate link. There is a gap in the literature on the description of a complete chain in addressing the structures of direct causal links of solar activity on terrestrial variables. This is why the present study uses the extensive facilities of the application of information theory in view of recent advances in different fields. Additionally, by other methods (e.g., neural networks) we first tested the existent non-linear links of solar–terrestrial influences on the hydro-climate system. The results related to the solar impact on terrestrial phenomena are promising, which is discriminant in the space-time domain. The implications prove robust for determining the causal measure of climate variables under direct solar impact, which makes it easier to consider solar activity in climate models by appropriate parametrizations. This study found that hydro-climatic variables are sensitive to solar impact only for certain frequencies (periods) and have a coherence with the Solar Flux only for some lags of the Solar Flux (in advance).

Styles APA, Harvard, Vancouver, ISO, etc.

33

Yassin, H., A. N. Tawfik et E. R. Abo Elyazeed. « Extensive/Nonextensive Statistics for pT Distributions of Various Charged Particles Produced in p + p and A + A Collisions in a Wide Range of Energies ». Ukrainian Journal of Physics 67, n^o 6 (27 octobre 2022) : 393. http://dx.doi.org/10.15407/ujpe67.6.393.

Texte intégral

Résumé :

A comprehensive review on various experimental parametrizations proposed to fit the transverse momentum distributions of charged pions, kaons, and protons produced at energies ranging between 7.7 GeV and 2.76 TeV is introduced. We present a systematic study for their statistical fits to the extensive Maxwell–Boltzmann (MB) and nonextensive statistics (generic axiomatic statistics and the Tsallis one as a special case). The inconsistency that the MB approach is to be utilized in characterizing the chemical freezeout, while the Tsallis approach determining the kinetic freezeout is discussed. The resulting energy dependence of the different fit parameters largely varies with the particle species and the degree of (non)extensivity. This manifests itself in that the Tsallis nonextensive approach seems to work well for p + p, rather than for A + A collisions. Nevertheless, discussing the deeper physical insights of nonextensive statistical approaches is not targeted, drawing a complete picture of the utilization of the Tsallis statistics in modeling the transverse momentum distributions of several charged particles produced at a wide range of energies and, accordingly, presenting a criticism or a support of the relevant works. This may be considered as the main advantage of this review.

Styles APA, Harvard, Vancouver, ISO, etc.

34

SUN, SHENGTAO, DINGSHENG LIU et GUOQING LI. « THE APPLICATION OF A HIERARCHICAL TREE METHOD TO ONTOLOGY KNOWLEDGE ENGINEERING ». International Journal of Software Engineering and Knowledge Engineering 22, n^o 04 (juin 2012) : 571–93. http://dx.doi.org/10.1142/s0218194012500155.

Texte intégral

Résumé :

Ontology technologies have been widely studied for their capabilities of semantic description and knowledge inference in a variety of application domains. The main obstacle for the advancement of ontologies is the immature building methods and construction principles. It is challenging to discover how to tune a large complete ontology to small applications and build domain ontologies pragmatically. This paper proposes a hierarchical tree method that provides guidelines to the building of a hierarchical geo-ontology and corresponding construction rules for different levels of ontologies. This hierarchical ontology construction method can be used to realize lower-level ontology building based on the restrictions of the upper-level ontology. It can also connect different levels of ontologies into a hierarchical structure. Based on the resulting hierarchical tree structure, the management and usage of ontologies becomes feasible and more efficient. Furthermore, to better elaborate the hierarchical relationships among the concepts surrounding the basic tree structure, this paper introduces Class Meta-Information (CMI) to OWL (Ontology Web Language) and uses Hierarchical Identification (HID) to draw conclusion on concepts' hierarchical relations. Examples, experimental simulation and comparative analyses are given to explain further the applications of this hierarchical tree method in the areas of ontology engineering.

Styles APA, Harvard, Vancouver, ISO, etc.

35

LI, SHASHA, et ZHOUJUN LI. « QUESTION-ORIENTED ANSWER SUMMARIZATION VIA TERM HIERARCHICAL STRUCTURE ». International Journal of Software Engineering and Knowledge Engineering 21, n^o 06 (septembre 2011) : 877–89. http://dx.doi.org/10.1142/s0218194011005475.

Texte intégral

Résumé :

In the research area of community-based question and answering (cQA) services such as Yahoo! Answers, reuse of the answers has attracted more and more interest. Most researchers focus on the correctness of answers and pay little attention to the completeness of answers. In this paper, we try to address the answer completeness problem for "survey questions" for which answer completeness is crucial. We propose to generate a more complete answer from replies in cQA services through a term hierarchical structure based question-oriented extractive summarization which is different from traditional query-based extractive summarization. The experimental results are very promising in terms of recall, precision and conciseness.

Styles APA, Harvard, Vancouver, ISO, etc.

36

Wang, Ying Lian, et Jun Yao Ye. « Research on Applied-Information Technology in Hierarchical Network Security Protocols Designing Based on Public Key ». Advanced Materials Research 951 (mai 2014) : 169–72. http://dx.doi.org/10.4028/www.scientific.net/amr.951.169.

Texte intégral

Résumé :

This paper proposed an applied-information technology in hierarchical network security protocols designing model based on public key, the designing of the protocols is to be completed in several layers. Each sub-protocol achieved a sub-goal that it should complete, and provided data interface to a higher sub-protocol. And then merged the sub-protocol of each layer, to complete the protocols designing. In the previous research, the security of the protocol in applied-information technology was always regarded as a whole, which caused the protocols designing to be tremendous complexity. The hierarchical model in applied-information technology simplifies the process of security protocols designing, and make the protocols designing more clear or less cost, the security proof more simpler.

Styles APA, Harvard, Vancouver, ISO, etc.

37

Commons, Michael Lamport, et Patrice Marie Miller. « A complete theory of human evolution of intelligence must consider stage changes ». Behavioral and Brain Sciences 25, n^o 3 (juin 2002) : 404–5. http://dx.doi.org/10.1017/s0140525x02240078.

Texte intégral

Résumé :

We show 13 stages of the development of tool-use and tool making during different eras in the evolution of Homo sapiens. We used the NeoPiagetian Model of Hierarchical Complexity rather than Piaget's. We distinguished the use of existing methods imitated or learned from others, from doing such a task on one's own.

Styles APA, Harvard, Vancouver, ISO, etc.

38

LOHREY, MARKUS. « COMPRESSED MEMBERSHIP PROBLEMS FOR REGULAR EXPRESSIONS AND HIERARCHICAL AUTOMATA ». International Journal of Foundations of Computer Science 21, n^o 05 (octobre 2010) : 817–41. http://dx.doi.org/10.1142/s012905411000757x.

Texte intégral

Résumé :

Membership problems for compressed strings in regular languages are investigated. Strings are represented by straight-line programs, i.e., context-free grammars that generate exactly one string. For the representation of regular languages, various formalisms with different degrees of succinctness (e.g., suitably extended regular expressions, hierarchical automata) are considered. Precise complexity bounds are derived. Among other results, it is shown that the compressed membership problem for regular expressions with intersection is PSPACE-complete. This solves an open problem of Plandowski and Rytter.

Styles APA, Harvard, Vancouver, ISO, etc.

39

Jacko, Julie A., et Gavriel Salvendy. « Hierarchical Menu Design : Breadth, Depth, and Task Complexity ». Perceptual and Motor Skills 82, n^o 3_suppl (juin 1996) : 1187–201. http://dx.doi.org/10.2466/pms.1996.82.3c.1187.

Texte intégral

Résumé :

In this research a relationship between an hierarchical menu's depth and the perceived complexity of a task involving menu retrieval was proposed and validated. 12 subjects were asked to use six different hierarchical menus of varying breadth and depth. The dependent variables were response time and accuracy. The independent variables were depth and breadth of the hierarchy. Subsequent to experimentation, the subjects were asked to complete a questionnaire on users' perceptions of the complexity of the different menu structures. As depth increased, perceived complexity of the menus increased significantly. These phenomena are linked to an existing theory of task complexity. We suggest that the cognitive component influencing users' perceptions of task complexity was short-term memory load.

Styles APA, Harvard, Vancouver, ISO, etc.

40

May, S. « RECURSIVE HIERARCHICAL CLUSTERING FOR HYPERSPECTRAL IMAGES ». ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B3-2020 (21 août 2020) : 461–65. http://dx.doi.org/10.5194/isprs-archives-xliii-b3-2020-461-2020.

Texte intégral

Résumé :

Abstract. Partition based clustering techniques are widely used in data mining and also to analyze hyperspectral images. Unsupervised clustering only depends on data, without any external knowledge. It creates a complete partition of the image with many classes. And so, sparse labeled samples may be used to label each cluster, and so simplify the supervised step. Each clustering algorithm has its own advantages, drawbacks (initialization, training complexity). We propose in this paper to use a recursive hierarchical clustering based on standard clustering strategies such as K-Means or Fuzzy-C-Means. The recursive hierarchical approach reduces the algorithm complexity, in order to process large amount of input pixels, and also to produce a clustering with a high number of clusters. Moreover, in hyperspectral images, a classical question is related to the high dimensionality and also to the distance that shall be used. Classical clustering algorithms usually use the Euclidean distance to compute distance between samples and centroids. We propose to implement the spectral angle distance instead and evaluate its performance. It better fits the pixel spectrums and is less sensitive to illumination change or spectrum variability inside a semantic class. Different scenes are processed with this method in order to demonstrate its potential.

Styles APA, Harvard, Vancouver, ISO, etc.

41

Jin, Huan, et Hunter N. B. Moseley. « Hierarchical Harmonization of Atom-Resolved Metabolic Reactions across Metabolic Databases ». Metabolites 11, n^o 7 (30 juin 2021) : 431. http://dx.doi.org/10.3390/metabo11070431.

Texte intégral

Résumé :

Metabolic models have been proven to be useful tools in system biology and have been successfully applied to various research fields in a wide range of organisms. A relatively complete metabolic network is a prerequisite for deriving reliable metabolic models. The first step in constructing metabolic network is to harmonize compounds and reactions across different metabolic databases. However, effectively integrating data from various sources still remains a big challenge. Incomplete and inconsistent atomistic details in compound representations across databases is a very important limiting factor. Here, we optimized a subgraph isomorphism detection algorithm to validate generic compound pairs. Moreover, we defined a set of harmonization relationship types between compounds to deal with inconsistent chemical details while successfully capturing atom-level characteristics, enabling a more complete enabling compound harmonization across metabolic databases. In total, 15,704 compound pairs across KEGG (Kyoto Encyclopedia of Genes and Genomes) and MetaCyc databases were detected. Furthermore, utilizing the classification of compound pairs and EC (Enzyme Commission) numbers of reactions, we established hierarchical relationships between metabolic reactions, enabling the harmonization of 3856 reaction pairs. In addition, we created and used atom-specific identifiers to evaluate the consistency of atom mappings within and between harmonized reactions, detecting some consistency issues between the reaction and compound descriptions in these metabolic databases.

Styles APA, Harvard, Vancouver, ISO, etc.

42

de Buy Wenniger, Gideon Maillette, et Khalil Sima’an. « Visualization, Search and Analysis of Hierarchical Translation Equivalence in Machine Translation Data ». Prague Bulletin of Mathematical Linguistics 101, n^o 1 (1 avril 2014) : 43–54. http://dx.doi.org/10.2478/pralin-2014-0003.

Texte intégral

Résumé :

Abstract Translation equivalence constitutes the basis of all Machine Translation systems including the recent hierarchical and syntax-based systems. For hierarchical MT research it is important to have a tool that supports the qualitative and quantitative analysis of hierarchical translation equivalence relations extracted from word alignments in data. In this paper we present such a toolkit and exemplify some of its uses. The main challenges taken up in designing this tool are the efficient and compact, yet complete, representation of hierarchical translation equivalence coupled with an intuitive visualization of these hierarchical relations. We exploit a new hierarchical representation, called Hierarchical Alignment Trees (HATs), which is based on an extension of the algorithms used for factorizing n-ary branching SCFG rules into their minimally-branching equivalents. Our toolkit further provides a search capability based on hierarchically relevant properties of word alignments and/or translation equivalence relations. Finally, the tool allows detailed statistical analysis of word alignments, thereby providing a breakdown of alignment statistics according to the complexity of translation equivalence units or reordering phenomena. We illustrate this with an empirical study of the coverage of inversion-transduction grammars for a number of corpora enriched with manual or automatic word alignments, followed by a breakdown of corpus statistics to reordering complexity.

Styles APA, Harvard, Vancouver, ISO, etc.

43

Suhirman, Suhirman, et Hero Wintolo. « System for Determining Public Health Level Using the Agglomerative Hierarchical Clustering Method ». Compiler 8, n^o 1 (22 mars 2019) : 95. http://dx.doi.org/10.28989/compiler.v8i1.425.

Texte intégral

Résumé :

Regions having higher level of welfare do not always have better indicator values than other regions having lower level of welfare. The problem is the lack of information related to the indicator values needed to determine the health level. Therefore, clustering using health data becomes necessary. Data were clustered to see the maximum or the minimum level of similarity. The clustered data were based on the similarity of four morality indicator values of the regional health level. Morality indicator values used in this research are infant mortality rate, child mortality rate, maternal mortality rate, and rough birth rate. The method used is Agglomerative Hierarchical Clustering (AHC) - Complete Linkage. Data were calculated using Euclidean Distance Equation, then Complete Linkage. Four clustered data were grouped into two clusters, healthy and/or unhealthy. The result, combining from all clusters into two large clusters to see healthy and unhealthy results.

Styles APA, Harvard, Vancouver, ISO, etc.

44

Lin, Zhe, Fan Zhang, Xuemin Lin, Wenjie Zhang et Zhihong Tian. « Hierarchical core maintenance on large dynamic graphs ». Proceedings of the VLDB Endowment 14, n^o 5 (janvier 2021) : 757–70. http://dx.doi.org/10.14778/3446095.3446099.

Texte intégral

Résumé :

The model of k -core and its decomposition have been applied in various areas, such as social networks, the world wide web, and biology. A graph can be decomposed into an elegant k -core hierarchy to facilitate cohesive subgraph discovery and network analysis. As many real-life graphs are fast evolving, existing works proposed efficient algorithms to maintain the coreness value of every vertex against structure changes. However, the maintenance of the k -core hierarchy in existing studies is not complete because the connections among different k -cores in the hierarchy are not considered. In this paper, we study hierarchical core maintenance which is to compute the k -core hierarchy incrementally against graph dynamics. The problem is challenging because the change of hierarchy may be large and complex even for a slight graph update. In order to precisely locate the area affected by graph dynamics, we conduct in-depth analyses on the structural properties of the hierarchy, and propose well-designed local update techniques. Our algorithms significantly outperform the baselines on runtime by up to 3 orders of magnitude, as demonstrated on 10 real-world large graphs.

Styles APA, Harvard, Vancouver, ISO, etc.

45

Drakopoulos, S. A., et A. D. Karayiannis. « The Historical Development of Hierarchical Behavior in Economic Thought ». Journal of the History of Economic Thought 26, n^o 3 (septembre 2004) : 363–78. http://dx.doi.org/10.1080/1042771042000263849.

Texte intégral

Résumé :

One of the basic ideas underlying the established conception of rational behavior is the unlimited substitutability of preferences. Economic agents are assumed to compare and reduce everything to a common denominator: utility. The most obvious example of such preferences can be found in standard consumer theory where complete substitutability of every good is assumed in the sense that a loss of some units of one bundle can always be compensated by gain of some units of another commodity (such preferences are sometimes called Archimedian—see Borch 1968). This conception of preferences has a long history in economic thought and forms the basis of the standard rational choice theory (Hicks and Allen 1934, Samuelson 1938, Hicks 1946, Houthakker 1950).

Styles APA, Harvard, Vancouver, ISO, etc.

46

Liao, Wei Hua. « Uncertainty Description of GIS Attribute Data in Hierarchical Approximate Space ». Advanced Materials Research 121-122 (juin 2010) : 760–63. http://dx.doi.org/10.4028/www.scientific.net/amr.121-122.760.

Texte intégral

Résumé :

GIS attribute data is the property of GIS entity, it has fuzziness and uncertainty. The binary relation for GIS entity object and attribute is meet to the property for approximate space. We choose the object and attribute of GIS information system in our study, use lattice concept, and we think the GIS entities can form partial order relation, and lattice(P(A), ) can form one complete partial order lattice. GIS entities can form hierarchical approximate space in subsection space relation, and the knowledge granularities are thining along with the increasing of attribution.

Styles APA, Harvard, Vancouver, ISO, etc.

47

Du, Tao, Qing Bei Guo, Kun Zhang et Kai Wang. « An Energy Aware Routing Algorithm for WSNs Based on Semi-Static Clustering ». Applied Mechanics and Materials 752-753 (avril 2015) : 1413–18. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.1413.

Texte intégral

Résumé :

Energy efficiency is a key factor to improve WSNs’ performance, and hierarchical routing algorithms are fitter in large scale networks and have more reliability, so they are mostly used to improve the nodes’ energy efficiency now. In this paper, mainly existing hierarchical routing algorithms are introduced, and based on these researches, a new energy efficient hierarchical routing algorithm designed based on energy aware semi-static clustering method is proposed. In this algorithm named EASCA, the nodes’ residual energy and cost of communication would both be considered when clustering. And a special packet head is defined to update nodes’ energy information when transmitting message; to rotate cluster head automatically, a member management scheme is designed to complete this function; and a re-cluster mechanism is used to dynamic adjust the clusters to make sensor nodes organization more reasonable. At last, EASCA is compared with other typical hierarchical routing algorithms in a series of experiments, and the experiments’ result proves that EASCA has obviously improved WSNs’ energy efficiency.

Styles APA, Harvard, Vancouver, ISO, etc.

48

Sitio, Arjon, Anita Sindar Sinaga, Akhyar Haikal et Sumitra Dewi. « MULTIVARIATE ANALYSIS OF COMMODITY AVAILABILITY OF STAPLE FOODS USING COMPLETE LINKAGE HIERARCHICAL CLUSTERING METHOD ». JITK (Jurnal Ilmu Pengetahuan dan Teknologi Komputer) 7, n^o 2 (18 février 2022) : 61–66. http://dx.doi.org/10.33480/jitk.v7i2.2830.

Texte intégral

Résumé :

The government directly supervises 11 basic food commodities. The system of interplay between the price of goods and the availability of staple food directly has an impact on the high price of food at certain times. It is necessary to classify the food that is most needed by the community on big holidays in Indonesia so that it can be a reference for the government in preparing market needs in the coming year. In this study, the grouping of staple food availability was based on hierarchical cluster analysis with complete linkage method. The availability of food commodities in the discussion of this research is sourced from production materials and daily prices for meat, eggs, cooking oil and rice commodities. Cluster interpretation results in cluster 1 indicating Fulfilled Availability of 88-89%, Cluster 2 showing Sufficient Commodity Availability of 90-93% and Cluster 3 showing Availability of Rare Commodities of 87%. The three clusters formed are depicted in the form of a dendogram as a visualization of the relationship between food availability groupings.

Styles APA, Harvard, Vancouver, ISO, etc.

49

Wang, Wenhu, Mallikarjuna N. Nadagouda et Sharmila M. Mukhopadhyay. « Flexible reusable hierarchical hybrid catalyst for rapid and complete degradation of triclosan in water ». Science of The Total Environment 766 (avril 2021) : 144109. http://dx.doi.org/10.1016/j.scitotenv.2020.144109.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

50

Haslett, Stephen. « Degrees of freedom and parameter estimability in hierarchical models for sparse complete contingency tables ». Computational Statistics & ; Data Analysis 9, n^o 2 (mars 1990) : 179–95. http://dx.doi.org/10.1016/0167-9473(90)90118-2.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Articles de revues sur le sujet « Hierarchical and complete parametrizations »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres