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81.
分析了晋城市城郊供电支公司县调通信和自动化专业运行水平低的原因及存在问题,提出了相应的解决方案。 相似文献
82.
殷建文 《科技情报开发与经济》2011,21(15):118-121
介绍了全国文化信息资源共享工程珠海支中心建设现状,阐述了珠海支中心建设与地、市级支中心共享工程建设要求存在的差距与不足,提出了地、市级文化信息资源共享工程建设的对策。 相似文献
83.
金银花茎中绿原酸和黄酮类化合物含量测定 总被引:10,自引:0,他引:10
采用分光光度法对金银花茎中的绿原酸及黄酮类化合物的含量进行了测定。结果表明,含量较高,具有开发利用的药用价值。 相似文献
84.
Class-based storage implementation decisions have significant impact on the required storage space and the material handling cost in a warehouse. In this paper, a nonlinear integer programming model is proposed to capture the above. Effects of storage area reduction on order picking and storage space cost are incorporated. A branch and bound algorithm is developed to solve the model. Computational experience with randomly generated data sets and an industrial case shows that branch and bound algorithm is computationally more efficient than a baseline dynamic programming algorithm. It is further observed that the class based policy results in lower total cost of order picking and storage space than the dedicated policy. 相似文献
85.
We begin this paper by identifying a class of stochastic mixed-integer programs that have column-oriented formulations suitable
for solution by a branch-and-price algorithm (B&P). We then survey a number of examples, and use a stochastic facility-location
problem (SFLP) for a detailed demonstration of the relevant modeling and solution techniques. Computational results with a
scenario representation of uncertain costs, demands and capacities show that B&P can be orders of magnitude faster than solving
the standard formulation by branch and bound. We also demonstrate how B&P can solve SFLP exactly – as exactly as a deterministic
mixed-integer program – when demands and other parameters can be represented as certain types of independent, random variables,
e.g., independent, normal random variables with integer means and variances.
Kevin Wood thanks the Office of Naval Research, Air Force Office of Scientific Research, the Naval Postgraduate School (NPS)
and the University of Auckland for their support. Eduardo Silva thanks NPS and the Brazilian Navy for their support. Both
authors are grateful to the COIN-OR team for assistance with computational issues, as well as to two anonymous referees for
highly useful, constructive criticism. 相似文献
86.
The paper provides full algorithmic details on switching to the continuation of all possible codim 1 cycle bifurcations from generic codim 2 equilibrium bifurcation points in n-dimensional ODEs. We discuss the implementation and the performance of the algorithm in several examples, including an extended Lorenz-84 model and a laser system. 相似文献
87.
Combined vehicle routing and scheduling with temporal precedence and synchronization constraints 总被引:1,自引:0,他引:1
We present a mathematical programming model for the combined vehicle routing and scheduling problem with time windows and additional temporal constraints. The temporal constraints allow for imposing pairwise synchronization and pairwise temporal precedence between customer visits, independently of the vehicles. We describe some real world problems where in the literature the temporal constraints are usually remarkably simplified in the solution process, even though these constraints may significantly improve the solution quality and/or usefulness. We also propose an optimization based heuristic to solve real size instances. The results of numerical experiments substantiate the importance of the temporal constraints in the solution approach. We also make a computational study by comparing a direct use of a commercial solver against the proposed heuristic, where the latter approach can find high quality solutions within specific time limits. 相似文献
88.
The free energy of nonideal two-component thermal plasma is calculated using the Poisson-Boltzmann equation. The possibility of the existence of a metastable state is shown for a component of heavy multicharged particles with particle charge values bounded from below and plasma temperature values bounded from above. The component of oppositely-charged light singly-charged particles and plasma generally do not feature the metastable state. 相似文献
89.
在 EAST 等离子体垂直位移快速控制电源(快控电源)的数字信号处理(DSP)执行控制程序远程升级中,
通过改变“二次引导”的顺序结构,提出一种新的“二次引导”结构。该结构不需要汇编语言的参与,使用 C
语言编写“二次引导”程序,同时将该结构与无线网络传输技术相结合,实现了对程序的远程升级固化。实验结果
表明,所提出的结合无线网络的“二次引导”结构能够实现对控制电源 DSP 程序的远程加密升级。 相似文献
90.
Harold P. Benson 《Journal of Global Optimization》1999,15(4):315-342
This article presents a new global solution algorithm for Convex Multiplicative Programming called the Outcome Space Algorithm. To solve a given convex multiplicative program (P
D), the algorithm solves instead an equivalent quasiconcave minimization problem in the outcome space of the original problem. To help accomplish this, the algorithm uses branching, bounding and outer approximation by polytopes, all in the outcome space of problem (P
D). The algorithm economizes the computations that it requires by working in the outcome space, by avoiding the need to compute new vertices in the outer approximation process, and, except for one convex program per iteration, by requiring for its execution only linear programming techniques and simple algebra. 相似文献