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排序方式: 共有832条查询结果,搜索用时 15 毫秒
271.
本文提出了一种时间片预分割方案,并将其用于多进程实时控制系统的软件设计,其特点是程序设计简单、维护方便,尤其是提高了系统运行的可靠性。 相似文献
272.
舒忠正 《南京航空航天大学学报》1987,(2)
本文叙述了在IBM-PC个人计算机上,研制成功的LISP跳棋智能程序中,如何成功地使用启发式搜索进行设计的方法,特别对作者自行设计的顺序递归搜索算法进行了分析和评价。 相似文献
273.
本文对洗衣机运转过程中的用水量建立优化模型,目标函数为在达到一定洗涤效果的前提下的最小用水量。我们将此归结为利用Lagrange函数求非线性规划的最优解问题,并且给出了相应的理论证明。此外,结合实际具体数据为洗衣机设计了一组运行程序。最后讨论了模型的改进与推广,并且对模型的优缺点作出了分析。 相似文献
274.
本文进一步介绍图形编辑和几何交切方面的程序设计的经验,如图形的映射、平移和旋转,交互绘图时常用到的九种几何交切的有关内容。用实例来说明程序设计原理和方法。 相似文献
275.
《中国航空学报》2020,33(1):308-323
Distributed Integrated Modular Avionics (DIMA) develops from Integrated Modular Avionics (IMA) and realizes distributed integration of multiple sub-function areas. Time-triggered network provides effective support for time synchronization and information coordination in DIMA systems. However, inconsistency between processing resources and communication network destroys the time determinism benefiting from partitions and time-triggered mechanism. To ensure such time determinism and achieve guaranteed real-time performance, system design should collectively provide a global communication scheme for messages in network domain and a corresponding execution scheme for partitions in processing domain. This paper firstly establishes a general DIMA model which coordinates partitioned processing and time-triggered communication, and then proposes a hybrid scheduling algorithm using Mixed Integer Programming to produce feasible system schemes. Furthermore, incrementally integrating new functions causes upgrades or reconfigurations of DIMA systems and will generate integration cost. To control such cost, this paper further develops an optimization algorithm based on Maximum Satisfiability Problem and guarantees that the scheduling design for upgraded DIMA systems inherit their original schemes as much as possible. Finally, two typical cases, including a simple fully connected DIMA system case and an industrial DIMA system case, are constructed to illustrate our DIMA model and validate the effectiveness of our hybrid scheduling algorithms. 相似文献
276.
Lijun Zong Jianjun Luo Mingming Wang Jianping Yuan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(8):1997-2009
This paper presents a novel obstacle avoidance constraint and a mixed integer predictive control (MIPC) method for space robots avoiding obstacles and satisfying physical limits during performing tasks. Firstly, a novel kind of obstacle avoidance constraint of space robots, which needs the assumption that the manipulator links and the obstacles can be represented by convex bodies, is proposed by limiting the relative velocity between two closest points which are on the manipulator and the obstacle, respectively. Furthermore, the logical variables are introduced into the obstacle avoidance constraint, which have realized the constraint form is automatically changed to satisfy different obstacle avoidance requirements in different distance intervals between the space robot and the obstacle. Afterwards, the obstacle avoidance constraint and other system physical limits, such as joint angle ranges, the amplitude boundaries of joint velocities and joint torques, are described as inequality constraints of a quadratic programming (QP) problem by using the model predictive control (MPC) method. To guarantee the feasibility of the obtained multi-constraint QP problem, the constraints are treated as soft constraints and assigned levels of priority based on the propositional logic theory, which can realize that the constraints with lower priorities are always firstly violated to recover the feasibility of the QP problem. Since the logical variables have been introduced, the optimization problem including obstacle avoidance and system physical limits as prioritized inequality constraints is termed as MIPC method of space robots, and its computational complexity as well as possible strategies for reducing calculation amount are analyzed. Simulations of the space robot unfolding its manipulator and tracking the end-effector’s desired trajectories with the existence of obstacles and physical limits are presented to demonstrate the effectiveness of the proposed obstacle avoidance strategy and MIPC control method of space robots. 相似文献
277.
《中国航空学报》2020,33(1):296-307
An improved approach is presented in this paper to implement highly constrained cooperative guidance to attack a stationary target. The problem with time-varying Proportional Navigation (PN) gain is first formulated as a nonlinear optimal control problem, which is difficult to solve due to the existence of nonlinear kinematics and nonconvex constraints. After convexification treatments and discretization, the solution to the original problem can be approximately obtained by solving a sequence of Second-Order Cone Programming (SOCP) problems, which can be readily solved by state-of-the-art Interior-Point Methods (IPMs). To mitigate the sensibility of the algorithm on the user-provided initial profile, a Two-Stage Sequential Convex Programming (TSSCP) method is presented in detail. Furthermore, numerical simulations under different mission scenarios are conducted to show the superiority of the proposed method in solving the cooperative guidance problem. The research indicated that the TSSCP method is more tractable and reliable than the traditional methods and has great potential for real-time processing and on-board implementation. 相似文献
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