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采用三因子五水平二次回归通用旋转组合设计试验,应用回归分析方法建立了洋芋丰产栽培技术模型,并进行了因子效应、交互效应、综合农艺措施寻优等方面的分析,获得高产优化农艺方案。 相似文献
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采用五元二次回归旋转正交组合设计方法,通过1990—1991年秋植蔗试验,建立蔗糖产量与种植密度,尿素、钙镁磷、氯化钾、桐麸的施用量等主要农艺措施之间的数学模型,得出各主要农艺措施及它们相互之间的作用对蔗糖产量的影响程度,并优选甘蔗生产的最优综合栽培农艺措施方案。 相似文献
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用优化理论指导生产试验获得的最佳方案,应该使产品质量和加工性能都好且原料成本低.本文介绍的方案特点之一是在试验设计过程中将三者紧密地联系在一起进行优选.同时,对多指标且需保证各项指标特性值应满足一定要求的试验设计,用多指标综合评分法就难于兼顾,本文介绍一种选优方法.结果,只经两轮试验就获得最佳方案,经济效应显著. 相似文献
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用多指标正交试验的区间取值(RTV)综合评分法优化泥浆的配制 总被引:2,自引:0,他引:2
雷焕鸣等.用多指标正交试验的区间取值(RTV)综合评分法优化泥浆的配制.数理统计与管理,1998,17(4),19~23.雷焕鸣等.用多指标正交试验的区间取值(RTV)综合评分法优化泥浆的配制.数理统计与管理,1998,17(4),19~23.本文提出多指标正交法设计的一种综合评分方法。并将这种方法应用于钻井液——泥浆的配置之中,优选出的最优方案很受现场技术人员的好评,获得了良好的经济效益 相似文献
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本考虑类别标准已确定的综合评判问题,将灰色理论中的关联分析用于Fuzzy综合评判模型,用灰色关联系数来替代隶属度,提出一种的综合评判的方法,运用于射击方案的优化. 相似文献
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崔文善,闫培生,张金政.木耳高产栽培配方的数学模型及优化研究.数理统计与管理,1997,16(4),8~11.本文采用回归正交设计方法,研究了泡桐木屑栽培木耳的配方组合与产量之间关系,并建立了数学模型。结果表明,以泡桐木屑为主料,各组分的适宜用量,以及它们之间合理组合,可显著提高木耳产量,降低生产成本,并具有较好的稳定性;其配方的优化方案为:泡桐木屑77.6~80.2%,麦夫12.5~14.8%,石灰2.4~2.7%,MgSO41.3%,KH2PO42.6%,糖1.0%。 相似文献
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基于PDE和几何曲率流驱动扩散的图像分析与处理 总被引:17,自引:0,他引:17
本文介绍由变分优化模型导出的偏微分方程(PDEs)模型与几何曲率流驱动扩散在图像恢复方面的应用,以及多种非线性异质扩散模型,讨论了PDEs模型在图像分析与处理方面的优点,理论与实验结果表明,要恢复得到商质量的图像,PDEs模型的利用是极为必要的.文中还介绍了求解PDEs模型的数值方案.其中,曲率计算是一个关键问题,其结果直接参与自适应扩散的控制.详细总结了基于有限差分和水平集方法,求解藕合非线性异质扩散模型方程的数值方案,追求高质量图像、高精度计算方法、降低计算复杂性是本文处理方法不断进步的发展动力。 相似文献
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Hybrid censoring scheme is a combination of Type‐I and Type‐II censoring schemes. Determination of optimum hybrid censoring scheme is an important practical issue in designing life testing experiments to enhance the information on reliability of the product. In this work, we consider determination of optimum life testing plans under hybrid censoring scheme by minimizing the total cost associated with the experiment. It is shown that the proposed cost function is scale invariant for some selected distributions. Optimum solution cannot be obtained analytically. We propose a method for obtaining the optimum solution and consider Weibull distribution for illustration. We also studied the sensitivity of the optimal solution to the misspecification of parameter values and cost components through a well‐designed sensitivity analysis. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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空中加油问题是一个关于在飞机飞行过程中,辅机在空中给主机加油来提高主机直航能力的问题.该题的要求是在辅机架数n一定的情况下,确定最优作战方案及主机的最大作战半径.对于问题1和问题2,首先给出了一般情况下的飞机调度的数学模型,然后用穷举法求出了n≤4情况下的最优作战方案及主机的最大作战半径rn,然后用归纳法推导出了n为一般情况下rn的上下界,最后给出了判断最优作战方案的必要条件.问题3中,给出了与问题1、问题2类似问题的求解结果.问题4中,首先求出了n≤4时空军基地的选址和最优作战方案,然后给出了n为一般情况下,最优作战方案和基地选址的通用数学模型.问题5中,在主机最快到达目的地并返回的条件下,给出了主机的飞行路线和最优作战方案;在满足辅机架数最少的条件下,给出了作战方案,并用MATLAB求出了满足该条件时的最少辅机架数的上界为248架.另外,给出了一些新的定义方法和定理并全部给予证明. 相似文献
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In the model of(k,n) multi-receiver authentication codes ( A-codes),a transmitter broadcasts a message m to nreceivers in such a way that not only an outside opponent butalso any k-1 receivers cannot cheat any other receiver.In this paper, we derive lower bounds on the cheating probabilitiesand the sizes of keys of (k,n) multi-receiver A-codes.The scheme proposed by Desmedt, Frankel and Yung meets all ourbounds with equalities. This means that our bounds are tightand their scheme is optimum. We further show a combinatorialstructure of optimum (k,n) multi-receiver A-codes.A notion of TWOOAs is introduced. A TWOOA is a pair of orthogonalarrays which satisfy a certain condition. We then prove thatan optimum (k,n) multi-receiver A-codeis equivalent to a TWOOA. 相似文献
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Our objective in this article is to present some numerical schemes for the approximation of the 2‐D Navier–Stokes equations with periodic boundary conditions, and to study the stability and convergence of the schemes. Spatial discretization can be performed by either the spectral Galerkin method or the optimum spectral non‐linear Galerkin method; time discretization is done by the Euler scheme and a two‐step scheme. Our results show that under the same convergence rate the optimum spectral non‐linear Galerkin method is superior to the usual Galerkin methods. Finally, numerical example is provided and supports our results. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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E. A. Freeman 《Journal of Optimization Theory and Applications》1969,3(6):416-443
The problem of optimizing a linear, time-variant, multivariable control system with quadratic cost functional is first phrased in the context of functional analysis. It is shown that the optimum control is given implicitly as the solution of a matrix integral equation. After the fixed-point contraction mapping theorem is invoked, an iterative method for solving this equation is developed and conditions for its convergence to a unique optimum are derived. Techniques for transforming the system operator are discussed so that, when convergence of the original sequence of iterations cannot be assured, that of the transformed system can. However, it is shown specifically that there is always a finite optimization interval for which the procedure may be used. Bounds are also given for the errors, in the sense of norms, between the control aftern iterations and its ultimate value and between the cost functional aftern iterations and its ultimate value. These bounds are used to decide when to terminate the sequence. Solutions of the iterative scheme using a hybrid computer in parallel and serial modes are discussed and the delays inherent in both methods calculated. It is concluded that the method can be used to track an optimum control system, which drifts from optimum because of parameter variations, with little delay and particularly when the optimization interval is extrapolated only a little into the future. Comparison of the proposed scheme with the steepest-descent approach developed by Balakrishnan shows that the present scheme requires one-third of the computations per step and, therefore, may converge more quickly.The author is indebted to the Principal and the Governors of Sunderland Polytechnic for the facilities placed at his disposal and permission to publish this work. 相似文献
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针对我国创业投资基金运作中独特的制度安排,对创业投资家在多任务环境下的激励问题进行了研究。Holmstrom和Milgrom的经典理论认为:若代理人在多任务中的努力投入可替代,则不同任务间的激励强度必须互补。然而本文的理论分析表明:1)若任务间的重要性存在差异,则最优的激励合约要求委托人增加重要任务的激励强度,同时降低其它任务的激励强度,即任务间的激励必然是对抗性的;2)若产出的分布受共同冲击的影响(正相关),则当任务间努力投入的替代系数较小时,应该对代理人实施对抗性激励,反之应对代理人实施互补性激励。对抗性激励机制的存在为委托人在某些环境下对高风险但重要任务实施强激励提供了理论依据。 相似文献
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针对复杂产品方案设计中指标属性信息的不完全性和不确定性,研究了一种基于粗糙数和信息熵理论的灰色关联评估模型。首先通过引入粗糙数序列的范数实现粗糙数评估矩阵的规范化处理,并利用熵权对指标属性值进行权重集结,然后构建理想最优特征序列,并借助基于信息还原算子的粗糙相似关联度来获得最优评估方案。信息熵赋权可减少主观赋权产生的人为因素影响,信息还原算子可避免评估过程中的信息失真现象。最后通过工程机械产品的实例,验证了该评估模型的有效性和实用性,便于对复杂产品的方案设计进行评估和优选。 相似文献