The precise integration algorithm (PIA) and the technique of dual vector formulation are extended to explore the axisymmetric response of multilayered transversely isotropic piezoelectric materials under the action of...
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The precise integration algorithm (PIA) and the technique of dual vector formulation are extended to explore the axisymmetric response of multilayered transversely isotropic piezoelectric materials under the action of external forces. The planes of cross-anisotropy are assumed to be parallel to the horizontal surface. The mechanical and electrical loads distributed over a circular area can be applied either on the surface of the layered system or at the interface between neighboring layers with dissimilar materials. By means of the Hankel integral transformation and the approach of dual vector form, the governing partial differential equations are reduced to the standard ordinary differential matrix equation. The PIA is exploited to evaluate the first-order ordinary differential matrix equation in the transformed domain. As the PIA is a highly accurate algorithm, any desired accuracy of axisymmetric piezoelectric solutions can be accomplished. The whole calculation is based on standard matrix algebra, and computational effort can be saved to a great extent. Furthermore, dual vector forms of key equations can facilitate the combination of adjacent strata. Finally, several numerical examples are given to validate the accuracy of the proposed technique and to investigate the influence of loading positions, types of external forces, stratified characters, and weak and thin interlayer on the response of the layered piezoelectric medium.
Additive models in censored regression are considered. A randomly weighted version of the backfitting algorithm that allows for the nonparametric estimation of the effects of the covariates on the response is provided...
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Additive models in censored regression are considered. A randomly weighted version of the backfitting algorithm that allows for the nonparametric estimation of the effects of the covariates on the response is provided. Given the high computational cost involved, binning techniques are used to speed up the computation in the estimation and testing process. Simulation results and the application to real data reveal that the predictor obtained with the additive model performs well, and that it is a convenient alternative to the linear predictor when some nonlinear effects are expected. (C) 2009 Elsevier B.V. All rights reserved.
Finding an optimal subset of features that maximizes classification accuracy is still an open problem. In this paper, we exploit the speed of the Harmony Search algorithm and the Optimum-Path Forest classifier in orde...
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Finding an optimal subset of features that maximizes classification accuracy is still an open problem. In this paper, we exploit the speed of the Harmony Search algorithm and the Optimum-Path Forest classifier in order to propose a new fast and accurate approach for feature selection. Comparisons to some other pattern recognition and feature selection techniques showed that the proposed hybrid algorithm for feature selection outperformed them. The experiments were carried out in the context of identifying non-technical losses in power distribution systems. (C) 2011 Elsevier Ltd. All rights reserved.
Core networks of the future will have a translucent and eventually transparent optical structure. Ultra-high-speed end-to-end connectivity with high quality of service and high reliability will be realized through the...
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Core networks of the future will have a translucent and eventually transparent optical structure. Ultra-high-speed end-to-end connectivity with high quality of service and high reliability will be realized through the exploitation of optimized protocols and lightpath routing algorithms. These algorithms will complement a flexible control and management plane integrated in the proposed solution. Physical layer impairments and optical performance are monitored and incorporated in impairment-aware lightpath routing algorithms. These algorithms will be integrated into a novel dynamic network planning tool that will consider dynamic traffic characteristics, a reconfigurable optical layer, and varying physical impairment and component characteristics. The network planning tool along with extended control planes will make it possible to realize the vision of optical transparency. This article presents a novel framework that addresses dynamic cross-layer network planning and optimization while considering the development of a future transport network infrastructure.
Second-generation sequencing (SGS) has advanced the study of crop genomes and has provided insights into diversity and evolution. However, repetitive DNA sequences in crops often lead to incomplete or erroneous assemb...
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Second-generation sequencing (SGS) has advanced the study of crop genomes and has provided insights into diversity and evolution. However, repetitive DNA sequences in crops often lead to incomplete or erroneous assemblies because SGS reads are too short to fully resolve these repeats. To overcome some of these challenges, long-read sequencing and optical mapping have been developed to produce high-quality assemblies for complex genomes. Previously, high error rates, low throughput, and high costs have limited the adoption of long-read sequencing and optical mapping. However, with recent improvements and the development of novel algorithms, the application of these technologies is increasing. We review the development of long-read sequencing and optical mapping, and assess their application in crop genomics for breeding improved crops.
This study focuses on the N-level batching problem with a hierarchical clustering structure. Clustering is the task of grouping a set of item types in such a way that item types in the same cluster are more similar (i...
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This study focuses on the N-level batching problem with a hierarchical clustering structure. Clustering is the task of grouping a set of item types in such a way that item types in the same cluster are more similar (in some sense or another) to each other than to those in other clusters. In hierarchical clustering structure, more and more different item types are clustered together as the level of the hierarchy increases. N-level batching is the process by which items with different types are grouped into several batches passed from level 1 to level N sequentially for given hierarchical clustering structure such that batches in each level should satisfy the maximum and minimum batch size requirements of the level. We consider two types of processing costs of the batches: unit processing cost and batch processing cost. We formulate the N-level batching problem with a hierarchical clustering structure as a nonlinear integer programming model with the objective of minimizing the total processing cost. To solve the problem optimally, we propose a multidimensional dynamic programming algorithm with an example.
作者：
Lee, HSTuckerman, MENYU
Dept Chem New York NY 10003 USA NYU
Courant Inst Math Sci New York NY 10003 USA
Finite temperature ab initio molecular dynamics (AIMD), in which forces are obtained from "on-the-fly" electronic structure calculations, is a widely used technique for studying structural and dynamical prop...
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Finite temperature ab initio molecular dynamics (AIMD), in which forces are obtained from "on-the-fly" electronic structure calculations, is a widely used technique for studying structural and dynamical properties of chemically active systems. Recently, we introduced an AIMD scheme based on discrete variable representation (DVR) basis sets, which was shown to have improved convergence properties over the conventional plane wave (PW) basis set [Liu,Y.;et al. Ph)u. Rev. B 2003, 68, 125110]. In the present work, the numerical algorithms for the DVR based AIMD scheme (DVR/AIMD) are provided in detail, and the latest developments of the approach are presented. The accuracy and stability of the current implementation of the DVR/AIMD scheme are tested by performing a simulation of liquid water at ambient conditions. The structural information obtained from the present work is in good agreement with the result of recent AIMD simulations with a PW basis set (PW/AIMD). Advantages of using the DVR/AIMD scheme over the PW/AIMD method are discussed. In particular, it is shown that a DVR/AIMD simulation of liquid water in the complete basis set limit is possible with a relatively small number of grid points.
We study the power of local computations on labelled edges (which allow two adjacent vertices to synchronize and to modify their states simultaneaously in function of their previous states) through the classical elect...
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We study the power of local computations on labelled edges (which allow two adjacent vertices to synchronize and to modify their states simultaneaously in function of their previous states) through the classical election problem. We characterize the graphs for which this problem has a solution. As corollaries we characterize graphs which admit an election algorithm for two seminal models: Angluin's model and asynchronous systems where processes communicate with synchronous message passing (i.e., there is a synchronization between the process sending the message and the one receiving it).
The operational reliability of the space manipulator is closely related to the control method. However the existing control methods seldom consider the operational reliability from the system level. A method to constr...
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The operational reliability of the space manipulator is closely related to the control method. However the existing control methods seldom consider the operational reliability from the system level. A method to construct the operational reliability system control model based on particle filter for the space manipulator is presented in this paper. Firstly, the definition of operational reliability and the degree of operational reliability are given and the state space equations of the control system are established as well. Secondly, based on the particle filter algorithm, a method to estimate the distribution of the end position error and calculate the degree of operational reliability with any form of noise distribution in real time is established. Furthermore, a performance model based on quality loss theory is built and a performance function is obtained to evaluate the quality of the control process. The adjustment value of the end position of the space manipulator can be calculated by using the performance function. Finally, a large number of simulation results show that the control method proposed in this paper can improve the task success rate effectively compared to the simulation results using traditional control methods and control methods based on Bayesian estimation.
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