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51.
具有周期非均匀扰动的色散管理系统中的孤子传输   总被引:4,自引:1,他引:4  
殷德京  李宏 《光子学报》2003,32(6):718-722
在准理想的色散管理系统中建立了非均匀扰动模型,研究了它们对孤子传输和相互作用的影响.这些扰动导致孤子崩塌,加剧了孤子间相互作用.它们影响的大小与周期长度和扰动强度有关,并且存在最坏周期长度和扰动共振现像.最后,引入非线性增益和滤波器来有效控制这些扰动的影响.  相似文献   
52.
Integrating logical constraints into optimal control problems is not an easy task. In fact, optimal control problems are usually continuous while logical constraints are naturally expressed by integer (binary) variables. In this article we are interested is a particular form of an LQR optimal control problem: the energy (control L2 norm) is to be minimized, system dynamic is linear and logical constraints on the control use are to be fulfilled. Even if the starting continuous problem is not a complicated one, difficulties arise when integrating the additional logical constraints. First, we will present two different ways of modeling the problem, both of them leading us to Mixed Integer Problems. Furthermore, algorithms (Generalized Outer Approximation, Benders Decomposition and Branch and Cut) are applied on each model and results analyzed. We also present a Benders Decomposition algorithm variant that is adapted to our problem (taking into account its particular form) and we will conclude by looking at the optimal solutions obtained in an interesting physical example: the harmonic spring.  相似文献   
53.
An issue of considerable importance involves the allocation of fixed costs or common revenue among a set of competing entities in an equitable way. Based on the data envelopment analysis (DEA) theory, this paper proposes new methods for (i) allocating fixed costs to decision making units (DMUs) and (ii) distributing common revenue among DMUs, in such a way that the relative efficiencies of all DMUs remain unchanged and the allocations should reflect the relative efficiencies and the input-output scales of individual DMUs. To illustrate our methods, numerical results for an example are described in this paper.  相似文献   
54.
曹剑中  高伟 《光子学报》1997,26(11):1050-1054
本文提出了一种间歇式高速同步相机的全新设计方法,介绍了系统的工作原理,硬件,软件设计以及核心控制算法,最后给出了实际应用结果。  相似文献   
55.
In this global world, many firms present a complex shareholding structure with indirect participation, such that it may become difficult to assess a firm’s controllers. Furthermore, if there are numerous dominant shareholders, the control can be shared between them. Determining who has the most influence is often a difficult task. To measure this influence, game theory allows the modeling of voting games and the computing of the Banzhaf index. This paper firstly offers a new algorithm to compute this index in all structures and then suggests some modelisations of the floating shareholder. Then, our model is applied to a real case study: the French group Lafarge. This exemplary case demonstrates how the float’s structure and hidden coalition can impact the power relationship between dominant shareholders.  相似文献   
56.
热电联产中热、电分摊比的合理确定   总被引:14,自引:1,他引:14  
符号表D蒸汽量HF燃料热值W电量下角标h供热比拥m煤耗。分摊比e环境,电n乏汽h比烙q比热量f给水0新汽在热电联产的成本分摊中,如何确定热、电分摊比,一直是一个很有争议的问题[‘-‘]。采用不同分摊方法,其热、电所得的经济效益相差甚大。因此,它直接关系到热力价格的合理制定,影响着供热企业的经济效益和热用户的利益,对热电联产事业的发展有着重要影响。本文在分析现有各种分摊方法的基础上,提出一个新的更为合理的分摊方法。1现有的分摊方法及其缺陷和应用范围1.1热量法将总热耗量按热、电两种能量数量的比例来分配[‘-‘…  相似文献   
57.
In this paper, we study the infinite-horizon expected discounted continuous-time optimal control problem for Piecewise Deterministic Markov Processes with both impulsive and gradual (also called continuous) controls. The set of admissible control strategies is supposed to be formed by policies possibly randomized and depending on the past-history of the process. We assume that the gradual control acts on the jump intensity and on the transition measure, but not on the flow. The so-called Hamilton–Jacobi–Bellman (HJB) equation associated to this optimization problem is analyzed. We provide sufficient conditions for the existence of a solution to the HJB equation and show that the solution is in fact unique and coincides with the value function of the control problem. Moreover, the existence of an optimal control strategy is proven having the property to be stationary and non-randomized.  相似文献   
58.
This article reports on an investigation into robust guaranteed cost control (GCC) for uncertain switched neutral systems (USNSs) with interval time‐varying mixed delays and nonlinear perturbations via dynamic output feedback. Delay‐dependent sufficient conditions are suggested to guarantee the robust exponential stability and to obtain robust GCC for USNSs using the average dwell time approach and the piecewise Lyapunov function technique in terms of a set of linear matrix inequalities. The problem of uncertainty in the system model is solved by deploying the Yakubovich lemma. Lastly, two examples (i.e., a numerical example and the water‐quality dynamic model for the Nile River) are given to verify the efficiency of the propounded theories. © 2016 Wiley Periodicals, Inc. Complexity 21: 555–578, 2016  相似文献   
59.
The model estimates, subject to restrictions, the functional relationship between national sulfur dioxide discharges and investment in control technology development. Estimates may be made for different product demands, allowed cost increases, and clean fuel availabilities. Control technology development may be accelerated by increased investment. Both optimal and sub-optimal solutions are calculated for an example problem. A general computing method is provided.The model was presented at the Industrial Process Design for Pollution Control Workshop, Chicago, Illinois, Oct. 1973; copyright released by the American Institute of Chemical Engineers for publication for the first time in the monographNormative Analysis in Policy Decisions: Public and Private.  相似文献   
60.
带模糊约束的最小费用流问题   总被引:3,自引:1,他引:3  
本文首次提出了带模糊约束的最小费用流问题,建立了相应的数学模型并给出了求解这一模型的有关算法。最后,给出了一个具体实例。  相似文献   
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