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121.
122.
M.A. Hoque 《European Journal of Operational Research》2011,215(1):80-88
This paper develops two generalized integrated inventory models to deliver a single product from a vendor to multiple buyers. To minimize the total cost of set up, ordering, inventory holding and transportation, the production flow is synchronized by transferring the lot with equal and/or unequal (either all are equal or all are unequal or a combination of equal and unequal) sized batches (sub-lots), each of which incurs a transportation cost. For easy implementation of the models, we relax some unrealistic assumptions in the existing models such as unlimited capacities of the transport equipment and buyers’ storage, insignificant set up and transportation times, unlimited lead time and batch sizes. A common optimal solution technique to the models is derived and their performances are analyzed. Potential significances of the solution method are highlighted with solutions of some numerical problems. The importance of the relaxed factors and limitation of the models are discussed. 相似文献
123.
采用广义方法研究红外目标跟踪中动态约束低效的问题,通过把测量点映射到值域的函数集,建立约束关系,接着对跟踪模型中的变换参量通过匹配点解出,最后对广义动态约束决策函数条件排序,同时修正约束条件,使整个系统在预定的时刻达到最佳跟踪效果。仿真实验表明该方法与动态约束算法相比能有效辨识动态目标,跟踪效果没有丢失现象。 相似文献
124.
We consider a nonsmooth multiobjective programming problem with inequality and set constraints. By using the notion of convexificator, we extend the Abadie constraint qualification, and derive the strong Kuhn-Tucker necessary optimality conditions. Some other constraint qualifications have been generalized and their interrelations are investigated. 相似文献
125.
126.
《Optimization》2012,61(5):747-775
This article is devoted to quantitative stability of a given primal-dual solution of the Karush–Kuhn–Tucker system subject to parametric perturbations. We are mainly concerned with those cases when the dual solution associated with the base primal solution is non-unique. Starting with a review of known results regarding the Lipschitz-stable case, supplied by simple direct justifications based on piecewise analysis, we then proceed with new results for the cases of Hölder (square root) stability. Our results include characterizations of asymptotic behaviour and upper estimates of perturbed solutions, as well as some sufficient conditions for (the specific kinds of) stability of a given solution subject to directional perturbations. We argue that Lipschitz stability of strictly complementary multipliers is highly unlikely to occur, and we employ the recently introduced notion of a critical multiplier for dealing with Hölder stability. 相似文献
127.
《Optimization》2012,61(6):517-534
We recapitulate the well-known fact that most of the standard constraint qualifications are violated for mathematical programs with equilibrium constraints (MPECs). We go on to show that the Abadie constraint qualification is only satisfied in fairly restrictive circumstances. In order to avoid this problem, we fall back on the Guignard constraint qualification (GCQ). We examine its general properties and clarify the position it occupies in the context of MPECs. We show that strong stationarity is a necessary optimality condition under GCQ. Also, we present several sufficient conditions for GCQ, showing that it is usually satisfied for MPECs. 相似文献
128.
129.
基于模态参数考虑边界条件变异的桥梁结构损伤识别 总被引:1,自引:0,他引:1
根据桥梁结构的实际工程特性,分析其边界条件变异、结构损伤及其参数变化,采用约束优化理论,建立以实测和理论模态参数误差平方和最小为目标函数的优化反演问题。基于矩阵摄动理论引入与结构动力方程对应的特征值和特征向量的一阶、二阶摄动量,将优化反演问题简化为非线性最小二乘法优化反演问题。针对桥梁结构边界条件对模态参数影响显著的实际情况,实施桥梁结构边界条件预识别,采用单元模态应变能方法预定位损伤,提出考虑边界条件变异的桥梁结构损伤识别具体流程。以一磁浮轨道梁方案为例,采用数值模拟进行边界条件变异及损伤的识别验证,结果表明:该方法能够有效识别边界条件的变异及构件损伤,识别参数的相对误差最大为12.48%,具有较高的识别精度。 相似文献
130.
Paul C. DeRose Melody V. Smith Klaus D. Mielenz Douglas H. Blackburn Gary W. Kramer 《Journal of luminescence》2009,129(4):349-355
Standard Reference Material (SRM) 2940 is a cuvette-shaped, Mn-ion-doped glass, recommended for use for relative spectral correction of emission and day-to-day performance validation of steady-state fluorescence spectrometers. Properties of this standard that influence its effective use or contribute to the uncertainty in its certified emission spectrum were explored here. These properties include its photostability, absorbance, dissolution rate in water, anisotropy, temperature coefficient of fluorescence intensity, and fluorescence lifetimes. Long and short lifetime components of the fluorescence displayed different emission spectra, making the certified spectrum useful with fluorescence instruments employing continuous excitation only. The expanded uncertainties in the certified spectrum are about 5% around the peak maximum at 620 nm, using an excitation wavelength of 412 nm. The SRM also exhibits a strong resistance to photodegradation, with no measurable decrease in fluorescence intensity even after 17 h of irradiation with the visible light from a Xe lamp. 相似文献