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排序方式: 共有653条查询结果,搜索用时 406 毫秒
1.
Circular neighbor-balanced designs using cyclic shifts   总被引:3,自引:0,他引:3  
In agriculture experiments, the response on a given plot may be affected by the treatments on neighboring plots as well as by the treatments applied to that plot. In this paper we consider such type of situations and construct circular neighbor-balanced designs (CNBDs) by the method of cyclic shifts or sets of shifts. An important feature of this method is that the properties of a design can be easily obtained from the sets of shifts instead of constructing the actual blocks of the design. That is, the off-...  相似文献
2.
Unsteady hydromagnetic rotating flow of a conducting second grade fluid   总被引:3,自引:0,他引:3  
The purpose of this work is to investigate the hydromagnetic oscillatory flow of a fluid bounded by a porous plate, when the entire system rotates about an axis normal to the plate. The fluid is assumed to be non-Newtonian (second grade), incompressible and electrically conducting. The magnetic field is applied transversely to the direction of the flow. Such a flow model has great significance not only of its theoretical interest, but also for applications to geophysics and engineering. The resulting initial value problem has been solved analytically for steady and unsteady cases. The analysis of the obtained results showed that the flow field is appreciably influenced by the material parameter of the second grade fluid, the applied magnetic field, the imposed frequency, rotation and suction and blowing parameters. It is observed in a second grade fluid that a steady asymptotic hydromagnetic solution exists for blowing and resonance which is different from the hydrodynamic situation.  相似文献
3.
Soft set theory based on its extension   总被引:2,自引:0,他引:2  
In this paper, we point out a defect that the definitions of soft subset and soft intersection in Maji’s paper are partial definitions, and then we introduce extension of soft set to redefine and simplify operations between soft sets. At last, we obtain some algebraic properties of new soft operations.  相似文献
4.
Monitoring process variability using auxiliary information   总被引:2,自引:1,他引:1  
In this study a Shewhart type control chart namely V r chart is proposed for improved monitoring of process variability (targeting large shifts) of a quality characteristic of interest Y. The proposed control chart is based on regression type estimator of variance using a single auxiliary variable X. It is assumed that (Y, X) follow a bivariate normal distribution. The design structure of V r chart is developed and its comparison is made with the well-known Shewhart control chart namely S 2 chart used for the same purpose. Using power curves as a performance measure it is observed that V r chart outperforms the S 2 chart for detecting moderate to large shifts, which is main target of Shewhart type control charts, in process variability under certain conditions on ρ yx . These efficiency conditions on ρ yx are also obtained for V r chart in this study.  相似文献
5.
6.
On the fractional differential equations with uncertainty   总被引:1,自引:0,他引:1  
This paper is based on the concept of fuzzy differential equations of fractional order introduced by Agarwal et al. [R.P. Agarwal, V. Lakshmikantham, J.J. Nieto, On the concept of solution for fractional differential equations with uncertainty, Nonlinear Anal. 72 (2010) 2859-2862]. Using this concept, we prove some results on the existence and uniqueness of solutions of fuzzy fractional differential equations.  相似文献
7.
微极流体向受热面的MHD驻点流动   总被引:1,自引:1,他引:0  
分析了有均匀横向磁场作用时,导电微极流体垂直冲击受热面时形成的二维驻点流动问题.应用适当的相似转换,将连续、动量、角动量及热量的控制方程,及其相应的边界条件,简化为无量纲形式.然后,利用以有限差分离散化为基础的算法,求解简化了的自相似非线性方程.用Richardson外推法,进一步求精其结果.以图表形式表示磁场参数、微极性参数、Prandtl数对流动和温度场的影响,说明了其解的重要特性.研究表明,随着磁场参数的增大,速度和热边界层厚度变小了.与Newton流体相比较,微极流体的剪应力和传热率出现明显的减少,这对聚合物生产过程中流体的流动和热量控制是有益的.  相似文献
8.
The unsteady flow of a Maxwell fluid induced by a constantly accelerating plate between two side walls perpendicular to the plate is studied. Exact solutions for the velocity field are established by means of the Fourier sine transforms. The adequate tangential stresses are also determined. The similar solutions for a Newtonian fluid are obtained as limiting cases of our solutions. In the absence of the side walls, the similar solutions for the unsteady flow over an infinite flat plate are recovered. Finally, for comparison, the velocity field in the middle of the channel and the shear stresses at the bottom wall and on the side walls are plotted for different values of the material constants.   相似文献
9.
Mixed quasi complementarity problems in topological vector spaces   总被引:1,自引:0,他引:1  
In this paper, we introduce and consider a new class of complementarity problems, which is called the mixed quasi complementarity problems in a topological vector space. We show that the mixed quasi complementarity problems are equivalent to the mixed quasi variational inequalities. Using the KKM mapping theorem, we study the existence of a solution of the mixed quasi variational inequalities and mixed quasi complementarity problems. Several special cases are also discussed. Results obtained in this paper can be viewed as extension and generalization of the previously known results.  相似文献
10.
A process variability control chart   总被引:1,自引:0,他引:1  
In this study a Shewhart type control chart namely the V t chart, is proposed for improved monitoring of the process variability of a quality characteristic of interest Y. The proposed control chart is based on the ratio type estimator of the variance using a single auxiliary variable X. It is assumed that (Y, X) follows a bivariate normal distribution. The design structure of the V t chart is developed for Phase-I quality control and its comparison is made with those of the S 2 chart (a well-known Shewhart control chart) and the V r chart (a Shewhart type control chart proposed by Riaz (Comput Stat, 2008a) used for the same purpose. It is observed that the proposed V t chart outperforms the S 2 and V r charts, in terms of discriminatory power, for detecting moderate to large shifts in the process variability. It is observed that the performance of the V t chart keeps improving with an increase in |ρ yx | , where ρ yx is the correlation between Y and X.  相似文献
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