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61.
本依据教育专业规划的定量分析方法,讲述了规划一所中学的办学模型的数学手段,提出了需考虑的主要因素,介绍了这些因素的量化方法,所应用的数学模型。  相似文献   
62.
63.
The large-scale base station planning problem for wideband code division multiple access (WCDMA) wireless networks is studied in this paper. A new rolling window optimization method is presented, where the global optimization problem is decomposed into small optimization sub-problems, which are defined on a series of successive rolling windows. Effective rolling strategies are designed in the rolling optimization method based on the prediction of the interference among the base stations in the WCDMA wireless network. We show that the proposed method has the property that the global objective is non-increasing in the successive optimization procedure. Simulations are carried out to analyze the performance of the proposed optimization method, which show the importance of the rolling strategy.  相似文献   
64.
应用最小二乘法准则,并改进了层次分析法判断矩阵的构成,获得考虑专家评价水平的诸影响因素权向量;基于集值统计法和属性数学原理,建立了对高等级公路路线方案量化综合评价优选模型,并给出了计算实例.  相似文献   
65.
An inventory model for a deteriorating item with stock dependent demand is developed under two storage facilities over a random planning horizon, which is assumed to follow exponential distribution with known parameter. For crisp deterioration rate, the expected profit is derived and maximized via genetic algorithm (GA). On the other hand, when deterioration rate is imprecise then optimistic/pessimistic equivalent of fuzzy objective function is obtained using possibility/necessity measure of fuzzy event. Fuzzy simulation process is proposed to maximize the optimistic/pessimistic return and finally fuzzy simulation-based GA is developed to solve the model. The models are illustrated with some numerical data. Sensitivity analyses on expected profit function with respect to distribution parameter λ and confidence levels α1 and α2 are also presented.  相似文献   
66.
The problem of periodicity for a non–homogeneous Markov model in a stochastic environment is studied. The stochastic concept is established through the notion of optional scenarios applied on the transition process. It is proved that the sequence of so–called aggregate structures follows a certain periodic pattern that can split into converging subsequences according to alternative policies. These limits are highly influenced by the different scenarios utilized in the model, but always lie on a convex region that also depends on the pool of alternatives.  相似文献   
67.
为了解决聚变堆遥操作维护上层控制系统普遍存在的软件功能模块过于集中、拓展性差、不具备中层运动规划能力等问题,设计了一种基于机器人操作系统(ROS)的上层协同控制系统。该系统采用分布式架构,基于市场成熟的开发平台进行设计,集成了中层运动规划与动力学虚拟仿真功能。通过“轴销抓取”的实验场景测试的结果表明:该系统满足设计需求,运行稳定。  相似文献   
68.
In this paper, a new planar one-legged robot model is firstly proposed, which, unlike previous one-legged robot with springy legs, consists of three revolute joints. Then a novel manner of one-legged locomotion (i.e., ballistic flip) is designed for this robot. A complete flipping gait cycle is composed of four phases: two stance phases and two flight phases. During flight phases, no active control is needed on the knee joint. Rotational motion and translational motion is decoupled from each other in flight phases. Landing of the robot is regarded as an inelastic impulsive impact. During stance phases, the robot model can be simplified as a two-degree-of-freedom rigid manipulator. Based on analysis of kinematics and dynamics of the flip robot, trajectory planning of cyclic flip gait is formulized as a problem of numerical optimization subject to nonlinear constraints such as positive reaction force of ground and finite torque of the joints. One potential application of the flipping robot is space exploration, which urgently requires the legged locomotive robots to be light-weighted and energy efficient.  相似文献   
69.
自由漂浮空间机械臂系统在无外力矩作用时,系统的动量矩守恒而成为非完整系统。利用这一特性本文研究了自由漂浮空间机械臂系统的三维姿态运动规划问题。导出带空间机械臂的航天器三维姿态运动数学模型,将系统的非完整运动规划问题转化为非线性系统最优控制问题,在最优控制中利用小波逼近控制输入规律,提出基于遗传算法的最优控制数值算法。通过数值仿真,表明该方法对带空间机械臂航天器系统的非完整姿态运动规划是有效的。  相似文献   
70.
In this paper we propose a planning procedure for serving freight transportation requests in a railway network with fast transfer equipment at terminals. We consider a transportation system where different customers make their requests (orders) for moving boxes, i.e., either containers or swap bodies, between different origins and destinations, with specific requirements on delivery times. The decisions to be taken concern the route (and the corresponding sequence of trains) that each box follows in the network and the assignment of boxes to train wagons, taking into account that boxes can change more than one train and that train timetables are fixed.The planning procedure includes a pre-analysis step to determine all the possible sequences of trains for serving each order, followed by the solution of a 0-1 linear programming problem to find the optimal assignment of each box to a train sequence and to a specific wagon for each train in the sequence. This latter is a generalized assignment problem which is NP-hard. Hence, in order to find good solutions in acceptable computation times, two MIP heuristic approaches are proposed and tested through an experimental analysis considering realistic problem instances.  相似文献   
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