检索结果-内蒙古大学图书馆

Uniform convergence and numerical computation of the Hubbell radiation rectangular source integral

RADIATION PHYSICS AND CHEMISTRY 2011年第12期80卷 1312-1315页

作者： Bairamov, Elgiz Ozalp, Nuni Ankara Univ Fac Sci Dept Math TR-06100 Ankara Turkey

In this paper, we investigate uniform convergence of the improper Hubbell radiation rectangular source (HRS) integral H(a,b). We prove that HRS integral H(a,b) is uniform convergent in the domain D = {(a,b) is an element of [0,A] x [0,infinity)} for any positive finite number A. Then we give an accurate and efficient computation algorithm for the HRS integral. (C) 2011 Elsevier Ltd. All rights reserved.

关键词： Radiation rectangular source integral Radiational field Uniform convergence computational algorithm

来源：评论

学校读者我要写书评

暂无评论

Exact equation and an algorithm for reliability evaluation of K-out-of-N:G system

引用

RELIABILITY ENGINEERING & SYSTEM SAFETY 2002年第2期78卷 87-91页

作者： Arulmozhi, G PSG Coll Technol Dept Math & Comp Applicat Coimbatore 641004 Tamil Nadu India

An expression for reliability of K-out-of-N:G system is proposed. An algorithm for computing reliability of K-out-of-N system is given. It is an easy to implement, fast and memory efficient algorithm and helps to impr... 详细信息

关键词： K-out-of-N : G system reliability recursive function computational algorithm

来源：评论

学校读者我要写书评

暂无评论

THE SCIENCE OF DATA SCIENCE

引用

BIG DATA 2014年第2期2卷 68-70页

作者： Fox, Peter Hendler, James Rensselaer Polytech Inst Inst Data Explorat & Applicat 110 8th St Troy NY 12180 USA

来源：评论

学校读者我要写书评

暂无评论

Analysis of Fan Waves in a Laboratory Model Simulating the Propagation of Shear Ruptures in Rocks

引用

JOURNAL OF APPLIED MECHANICS AND TECHNICAL PHYSICS 2017年第7期58卷 1139-1152页

作者： Tarasov, B. G. Sadovskii, V. M. Sadovskaya, O. V. Univ Western Australia Ctr Offshore Fdn Syst Perth WA 6009 Australia Inst Computat Modeling SB RAS Krasnoyarsk 660036 Russia

The fan-shaped mechanism of rotational motion transmission in a system of elastically bonded slabs on flat surface, simulating the propagation of shear ruptures in super brittle rocks, is analyzed. Such ruptures appear in the Earth's crust at seismogenic depths. They propagate due to the nucleation of oblique tensile microcracks, leading to the formation of a fan domino-structure in the rupture head. A laboratory physical model was created which demonstrates the process of fan-structure wave propagation. Equations of the dynamics of rotational motion of slabs as a mechanical system with a finite number of degrees of freedom are obtained. Based on the Merson method of solving the Cauchy problem for systems of ordinary differential equations, the computational algorithm taking into account contact interaction of slabs is developed. Within the framework of a simplified mathematical model of dynamic behavior of a fan-shaped system in the approximation of a continuous medium, the approximate estimates of the length of a fan depending on the velocity of its motion are obtained. It is shown that in the absence of friction a fan can move with any velocity that does not exceed the critical value, which depends on the size, the moment of inertia of slabs, the initial angle and the elasticity coefficient of bonds. In the presence of friction a fan stops. On the basis of discrete and continuous models, the main qualitative features of the behavior of a fan-structure moving under the action of applied tangential forces, whose values in a laboratory physical model are regulated by a change in the inclination angle of the rupture plane, are analyzed. Comparison of computations and laboratory measurements and observations shows good correspondence between the results.

关键词： fan-shaped mechanism Lagrange equations Euler equation traveling waves computational algorithm

来源：评论

学校读者我要写书评

暂无评论

Improved Potter-Anderson-Moore algorithm for the differential Riccati equation

引用

APPLIED MATHEMATICS AND COMPUTATION 2011年第8期218卷 4641-4646页

作者： Radisavljevic, Verica Calif State Univ Los Angeles Dept Mech Engn Los Angeles CA 90032 USA

The paper presents a method to find the solution of the constant coefficient matrix differential Riccati differential in terms of solutions of algebraic Riccati and Lyapunov equations, and the state transition matrix (matrix exponential) of the corresponding linear dynamic system. The method presented represents an improved method of Potter-Anderson-Moore since the solution is obtained under milder assumptions than the original algorithm of Potter-Anderson-Moore. An aircraft and satellite examples done in the paper demonstrate the advantages of the improved algorithm. (C) 2011 Elsevier Inc. All rights reserved.

关键词： Riccati differential equation computational algorithm Linear-quadratic optimal control Finite-horizon optimal linear filtering Kalman filtering

来源：评论

学校读者我要写书评

暂无评论

RELIABILITY MODELING AND EVALUATION TECHNIQUES FOR POWER DISTRIBUTION NETWORKS WITH LOCAL GENERATION

引用

IEE PROCEEDINGS-C GENERATION TRANSMISSION AND DISTRIBUTION 1987年第5期134卷 348-356页

作者： DIALYNAS, EN ALLAN, RN UNIV MANCHESTER INST SCI & TECHNOLDEPT ELECT ENGN & ELECTRMANCHESTER M60 1QDLANCSENGLAND

Local generating facilities in power distribution networks can be used to supply the load, when the bulk supply points become unavailable, to a load point during outage conditions. The purpose of the paper is to describe and demonstrate the modelling and evaluation techniques that are necessary to translate the conceptual ideas of local generation to practical analysis. These techniques construct the relevant statespace diagrams and identify the system down states. The steady-state probabilities of a general state-space diagram are evaluated by applying a set of equations and a computational algorithm to minimise the computer storage and time requirements and eliminate the rounding errors incurred when a conventional Markov approach is used. The algorithm developed is suitable for either computer implementation to analyse complex systems or hand calculations to analyse simple systems. A typical distribution system is analysed which illustrates the additional results and information that can be achieved from the use of these extended system models.

关键词： state-space diagrams complex system analysis Reliability evaluation techniques computational algorithm distribution networks power distribution networks system down states local generation outage conditions Distribution networks electric power generation reliability simple system analysis steady-state probabilities Maintenance and reliability modelling

来源：评论

学校读者我要写书评

暂无评论

An optimal design of multiattribute control charts for processes subject to a multiplicity of assignable causes

引用

APPLIED MATHEMATICS AND COMPUTATION 2000年第2-3期114卷 187-203页

作者： Jolayemi, JK Univ Zululand Dept Math & Stat ZA-3886 Kwa Dlangezwa KwaZulu Natal South Africa

We have developed a model for the optimal design of multiattribute control charts (MACCs) for processes subject to multiple assignable causes. The development of the model is based on the J approximation (J.K. Jolayemi, Comput. Stat. Data Anal., 18, 1994, pp 403-417;J.K. Jolayemi and J.N. Berrettoni, Appl. Math. Comput. 32 (1) (1989) pp. 1-16) and on the modification and extension of Gibra's model for the design of attribute control charts (I.N. Gibra, J. Quality Technol. 13 (2) (1981) pp. 93-99). A computational procedure for optimizing the model is presented. Some numerical examples are given to illustrate the model and the computational procedure. The examples show that the MACC and its design parameters are very sensitive to changes in the values of the input parameters. The model does not require any approximation by the "matching" process (see I.N. Gibra, J. Quality Technol. 13 (2) (1981) pp. 93-99 for an example of the matching process), as an exact solution to it is very easy to obtain. The justifications for applying the J approximation (JA) are illustrated by numerical examples. The numerical examples show that JA is very accurate in determining sample sizes. The examples also show that unlike when used to compute convolution probability values, JA is indifferent to the differences in the values of the proportion defectives when applied for determining sample sizes - whatever the magnitudes of the differences. (C) 2000 Elsevier Science Inc. All rights reserved.

关键词： convolution approximation binomial variables design parameters computational algorithm

来源：评论

学校读者我要写书评

暂无评论

An algorithm for simulating solid objects suspended in stratified flow

引用

COMPUTER PHYSICS COMMUNICATIONS 1997年第1-3期102卷 147-160页

作者： Xiao, F Yabe, T Ito, T Tajima, M TOKYO INST TECHNOL GRAD SCH NAGATSUTADEPT ENERGY SCIMIDORI KUYOKOHAMAKANAGAWA 227JAPAN

An efficient difference algorithm for computing directly deformation less solid objects suspended in stratified flow in 2D has been developed. The objects are represented by colour functions (or density functions) and predicted by a sharpness preserving scheme that is able to prevent the numerical diffusion across the sharp interface, Pressure distribution is then calculated by a unified solver and the solid object is treated as a mass of material of high sound speed, The motion of the solid object is decomposed into translation and rotation, and the force as well as the torque that cause change in the motion of the solid body are evaluated by an averaging calculation over the region occupied by the solid body. Calculations are conducted on a fixed grid system, Operations for reconstructing moving interfaces or dealing with inner boundary conditions are not necessary.

关键词： computational algorithm fluid dynamics stratified flow suspended objects

来源：评论

学校读者我要写书评

暂无评论

Solving equations simulating the steady-state behavior of the multi-stage flash desalination process

引用

DESALINATION 1996年第2期107卷 171-193页

作者： ElDessouky, H Bingulac, S KUWAIT UNIV DEPT ELECT & COMP ENGNSAFAT 13060KUWAIT

The paper presents an algorithm for solving the equations simulating the steady-state behavior of the multi-stage flash(MSF) desalination process. The model can be used either for designing new plants or analysis and optimization of existing units. The set of equations relating the large number of design and operating variables for any stage (i-th stage) in MSF plants is broken down into three subsets. The first subset contains equations describing processes in the tubes of the preheater inside the flashing chamber. The second subset deals with the processes inside the flashing chamber. These two subsets of equations are subsequently solved iteratively involving only a single variable for each subset. These variables are: (1) saturation temperature T-vi of the flashed-off vapor and (2) temperature of the unevaporated brine flowing from the chamber. The third subset of equations considers the existing interactions between the first two subsets. This subset defines the mass of vapor formed by flashing D-i in the i-th stage. All equations in the above-mentioned subsets are solved by a reliable and efficient one-dimensional fixed-point iteration. The main advantages of this method are less sensitivity to initial guesses, fewer iterations to obtain the required solution, and no need for calculating derivatives. The algorithm is implemented using the computer-aided design (CAD) interative package L-A-S (Linear Algebra and Systems). Detailed results are presented to show the dependence of the important factors controlling the fresh water cost, which are plant performance ratio, specific heat transfer area, specific brine flow rate, and specific cooling water now rate, on the most significant two design variables, namely the total number of stages and the top brine temperature. The predicted data hem the model are compared with published data of a typical MSF plant in operation at Kuwait. The agreement was found to be very good.

关键词： MSF desalination process modelling and simulation of MSF plants stage-by-stage algorithm non-linear equations computational algorithm

来源：评论

学校读者我要写书评

暂无评论

A new method to measure complexity in binary or weighted networks and applications to functional connectivity in the human brain

引用

BMC BIOINFORMATICS 2016年第1期17卷 1-18页

作者： Hahn, Klaus Massopust, Peter R. Prigarin, Sergei HMGU German Res Ctr Environm Hlth Inst Computat Biol Ingolstadter Landstr 1 D-85764 Neuherberg Germany Tech Univ Munich Ctr Math Res Unit M6 D-85747 Garching Germany Novosibirsk State Univ Inst Computat Math & Math Geophys Siberian Branch Russian Acad Sci Novosibirsk 630090 Russia

Background: Networks or graphs play an important role in the biological sciences. Protein interaction networks and metabolic networks support the understanding of basic cellular mechanisms. In the human brain, networks of functional or structural connectivity model the information-flow between cortex regions. In this context, measures of network properties are needed. We propose a new measure, Ndim, estimating the complexity of arbitrary networks. This measure is based on a fractal dimension, which is similar to recently introduced box-covering dimensions. However, box-covering dimensions are only applicable to fractal networks. The construction of these network-dimensions relies on concepts proposed to measure fractality or complexity of irregular sets in R-n. Results: The network measure Ndim grows with the proliferation of increasing network connectivity and is essentially determined by the cardinality of a maximum k-clique, where k is the characteristic path length of the network. Numerical applications to lattice-graphs and to fractal and non-fractal graph models, together with formal proofs show, that Ndim estimates a dimension of complexity for arbitrary graphs. Box-covering dimensions for fractal graphs rely on a linear log-log plot of minimum numbers of covering subgraph boxes versus the box sizes. We demonstrate the affinity between Ndim and the fractal box-covering dimensions but also that Ndim extends the concept of a fractal dimension to networks with non-linear log-log plots. Comparisons of Ndim with topological measures of complexity ( cost and efficiency) show that Ndim has larger informative power. Three different methods to apply Ndim to weighted networks are finally presented and exemplified by comparisons of functional brain connectivity of healthy and depressed subjects. Conclusion: We introduce a new measure of complexity for networks. We show that Ndim has the properties of a dimension and overcomes several limitations of presently used topolo

关键词： Network analysis Complexity measure computational algorithm Fractal dimension Human brain application Functional connectivity

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：