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81.
仓库容量有限条件下的一类存贮管理模型 总被引:10,自引:1,他引:9
建立了一类仓库容量有限条件下存贮管理决策模型 ,给出最优存贮策略 . 相似文献
82.
On the properties of solutions to the Goursat-Darboux problem with boundary and distributed controls
N. I. Pogodaev 《Siberian Mathematical Journal》2007,48(5):897-912
We consider a control system described by the Goursat-Darboux equation. The system is controlled by distributed and boundary controls. The controls are subject to the constraints given as multivalued mappings with closed, possibly nonconvex, values depending on the phase variable. Alongside the initial constraints, we consider the convexified constraints and the constraints whose values are the extreme points of the convexified constraints. We study the questions of existence of solutions and establish connections between the solutions under various constraints. 相似文献
83.
This article focuses on discontinuous Galerkin method for the two‐ or three‐dimensional stationary incompressible Navier‐Stokes equations. The velocity field is approximated by discontinuous locally solenoidal finite element, and the pressure is approximated by the standard conforming finite element. Then, superconvergence of nonconforming finite element approximations is applied by using least‐squares surface fitting for the stationary Navier‐Stokes equations. The method ameliorates the two noticeable disadvantages about the given finite element pair. Finally, the superconvergence result is provided under some regular assumptions. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 23: 421–436, 2007 相似文献
84.
本文利用一个新的分片线性NCP函数提出一个新的可行的QP-free方法解非线性不等式约束优化问题.不同于其他的QP-free方法,这个方法只考虑在工作集中的约束函数,工作集是积极集的一个估计,因此子问题的维数不是满秩的.这个方法可行的并且不需假定严格互补条件、聚点的孤立性得到算法的全局收敛性,并且积极约束函数的梯度不要求线性独立的,其中由拟牛顿法得到的子矩阵不需要求一致正定性. 相似文献
85.
We report on further developments in the three-dimensional tracking of a particle deep within the tumbling ball charge of
an experimental mill. The experimental X-ray program employing the use of bi-planar X-ray angiography now includes the tracking
of a typical 6 mm bulk charge particle in three dimensions with a spatial resolution that is accurate to within 0.15 mm. The
improved experimental tracking techniques presented were developed for the purpose of generating accurate three-dimensional
particle trajectory data against which to validate a numerical method for the simulation of discrete media, namely the discrete
element method (DEM). These improvements are complimented with techniques for comparing charge profiles between numerical
DEM simulations and three-dimensional experimental trajectory data. 相似文献
86.
In this paper, the authors present airflow field characteristics of human upper airway and soft palate movement attitude during
breathing. On the basis of the data taken from the spiral computerized tomography images of a healthy person and a patient
with Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS), three-dimensional models of upper airway cavity and soft palate are
reconstructed by the method of surface rendering. Numerical simulation is performed for airflow in the upper airway and displacement
of soft palate by fluid-structure interaction analysis. The reconstructed three-dimensional models precisely preserve the
original configuration of upper airways and soft palate. The results of the pressure and velocity distributions in the airflow
field are quantitatively determined, and the displacement of soft palate is presented. Pressure gradients of airway are lower
for the healthy person and the airflow distribution is quite uniform in the case of free breathing. However, the OSAHS patient
remarkably escalates both the pressure and velocity in the upper airway, and causes higher displacement of the soft palate.
The present study is useful in revealing pathogenesis and quantitative mutual relationship between configuration and function
of the upper airway as well as in diagnosing diseases related to anatomical structure and function of the upper airway.
The project supported by the National Natural Science Foundation of China (10672036, 10472025 and 10421002), the Natural Science
Foundation of Liaoning Province (20032109).
English text was polished by Yunming Chen. 相似文献
87.
Generators of some Ramanujan formulas 总被引:2,自引:0,他引:2
Jesús Guillera 《The Ramanujan Journal》2006,11(1):41-48
In this paper we prove some Ramanujan type formulas for 1/π but without using the theory of modular forms. Instead we use
the WZ—method created by H. Wilf and D. Zeilberger and find some hypergeometric functions in two variables which are second
components of WZ—pairs than can be certified using Zeilberger's EKHAD package. These certificates have an additional property
which allows us to get generalized Ramanujan's type series which are routinely proven by computer. We call these second hypergeometric
components of the WZ—pairs generators. Finding generators seems a hard task but using a kind of experimental research (explained
below), we have succeeded in finding some of them. Unfortunately we have not found yet generators for the most impressive
Ramanujan's formulas. We also prove some interesting binomial sums for the constant 1/π2. Finally we rewrite many of the obtained series using pochhammer symbols and study the rate of convergence.
2000 Mathematics Subject Classification Primary—33C20 相似文献
88.
四阶方程两点边值问题Hermite有限元解的渐近展式与外推 总被引:1,自引:0,他引:1
1引言有限元解的渐近展式是提高微分方程数值解精度的重要工具,比如亏量校正和外推就是建立在有限元解的渐近展式的基础之上.许多作者对此进行了大量的研究(见[1]-[4]),特别是文[1],提出了在研究有限元解的渐近展式中十分有用的能量嵌入技巧.本文利用能量嵌入定理得到了四阶方程两点边值问题Hermite有限元解及其二阶平均导数的渐近展式,进一步我们还讨论了它们的Richardson外推公式.考虑四阶方程两点边值问题 相似文献
89.
90.
Labour scheduling plays an important and critical role in Sainsburys day to day operations and profitability. The integrated
workforce management solution for Sainsburys is an intelligent solution for the operational deployment of human resources,
integrated business forecasting, generation and calculation of workload and staff scheduling. The workforce management technology
has provided Sainsburys with a fully web-based and centralised system that produces optimised schedules for all employees
satisfying the forecasted demand of work with granularity of fifteen minutes. The system is configured to respect all operational
and business requirements as well as employee contractual constraints. This paper introduces the workforce management solution
system designed, developed and implemented for Sainsburys. We concentrate on two modelling structures, namely the work pattern
model and optimisation model, and briefly discuss the optimisation process. 相似文献