全文获取类型
收费全文 | 48篇 |
免费 | 4篇 |
国内免费 | 10篇 |
专业分类
电工技术 | 1篇 |
综合类 | 4篇 |
化学工业 | 5篇 |
金属工艺 | 1篇 |
机械仪表 | 3篇 |
轻工业 | 2篇 |
石油天然气 | 3篇 |
武器工业 | 5篇 |
无线电 | 4篇 |
一般工业技术 | 4篇 |
自动化技术 | 30篇 |
出版年
2024年 | 1篇 |
2021年 | 3篇 |
2020年 | 8篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 5篇 |
2014年 | 3篇 |
2013年 | 7篇 |
2012年 | 8篇 |
2011年 | 4篇 |
2010年 | 3篇 |
2009年 | 2篇 |
2008年 | 6篇 |
2007年 | 3篇 |
2006年 | 1篇 |
2004年 | 2篇 |
2002年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有62条查询结果,搜索用时 15 毫秒
1.
低空复杂环境下基于采样空间约减的无人机在线航迹规划算法 总被引:1,自引:0,他引:1
针对低空复杂环境下障碍物密集且类型多样、带有多通道并存在不确定信息的无人机在线航迹规划问题,为了减少碰撞检测次数,提高航迹搜索速度,降低航迹代价,提出一种基于采样空间约减的无人机在线航迹规划算法. 算法通过引入代价模型,提出约减域逐步构造方法,引导规划树快速有效扩展,改善了基于动态域的快速拓展随机树(Dynamic domain rapidly-exploring random tree,DDRRT) 算法中存在的采样空间过度约减问题. 算法通过密度划分索引的方法逐步构建多棵Kd 树(K-dimensional tree)并采用多近邻节点搜索方法,加快了近邻树节点搜索速度. 仿真实验结果表明,与DDRRT方法相比,该方法在保证对采样空间约减合理性的同时,提高了航迹规划效率和通道内的寻路能力. 相似文献
2.
3.
Ata Allah Taleizadeh Seyed Taghi Akhavan Niaki Seyed Mohammad Haji Seyedjavadi 《Journal of Manufacturing Systems》2012
In this paper, a multiproduct inventory control problem is considered in which the periods between two replenishments of the products are assumed independent random variables, and increasing and decreasing functions are assumed to model the dynamic demands of each product. Furthermore, the quantities of the orders are assumed integer-type, space and budget are constraints, the service-level is a chance-constraint, and that the partial back-ordering policy is taken into account for the shortages. The costs of the problem are holding, purchasing, and shortage. We show the model of this problem is an integer nonlinear programming type and to solve it, a harmony search approach is used. At the end, three numerical examples of different sizes are given to demonstrate the applicability of the proposed methodology in real world inventory control problems, to validate the results obtained, and to compare its performances with the ones of both a genetic and a particle swarm optimization algorithms. 相似文献
4.
Seyed Hamid Reza Pasandideh Seyed Taghi Akhavan Niaki Sharareh Sharafzadeh 《Journal of Manufacturing Systems》2013
In this paper, a bi-objective multi-products economic production quantity (EPQ) model is developed, in which the number of orders is limited and imperfect items that are re-workable are produced. The objectives of the problem are minimization of the total inventory costs as well as minimizing the required warehouse space. The model is shown to be of a bi-objective nonlinear programming type, and in order to solve it two meta-heuristic algorithms namely, the non-dominated sorting genetic algorithm (NSGA-II) and multi-objective particle swarm optimization (MOPSO) algorithm, are proposed. To verify the solution obtained and to evaluate the performance of proposed algorithms, two-sample t-tests are employed to compare the means of the first objective value, the means of the second objective values, and the mean required CPU time of solving the problem using two algorithms. The results show while both algorithms are efficient to solve the model and the solution qualities of the two algorithms do not differ significantly, the computational CPU time of MOPSO is considerably lower than that of NSGA-II. 相似文献
5.
Analytical models of multi-product manufacturing systems operating under CONWIP control are composed of closed queuing networks with synchronization stations. Under general assumptions, these queuing networks are hard to analyze exactly and therefore approximation methods must be used for performance evaluation. This research proposes a new approach based on parametric decomposition. Two-moment approximations are used to estimate the performance measures at individual stations. Subsequently, the traffic process parameters at the different stations are linked using stochastic transformation equations. The resulting set of non-linear equations is solved using an iterative algorithm to obtain estimates of key performance measures such as throughput, and mean queue lengths. Numerical studies indicate that the proposed method is computationally efficient and yields fairly accurate results when compared to simulation. 相似文献
6.
在原有的正向物流基础上,将逆向物流并入其中,构成一个闭环的物流网络。以总闭环物流运输成本、库存成本、惩罚成本和建设成本之和最低为目标,建立闭环物流网络数学规划模型,实现了在闭环物流系统宏观总需求前提下的微观物流计划安排,并利用分支定界法解出其最优解。实例分析结果表明,宏微观协同决策模型较好地补充了传统闭环物流模型的静态单目标单产品问题,可以解决动态多目标多产品的决策问题,实现了供应链设计宏观战略和微观战术的结合。 相似文献
7.
针对网络优化领域中的多约束网络路径优化问题,以战时供应保障路径优化问题为研究对象,建立一种保障代价最小的路径优化模型。分析保障路径优化中存在多约束限制问题的特点,在基本蚁群算法的基础上引入蚂蚁相遇策略,融合了多约束条件对保障路径优化的影响,通过正、逆反馈同时作用,对信息素更新策略进行改进,并对搜索最优保障路径实例的仿真。仿真结果显示:改进蚁群算法平均执行时间较基本蚁群算法提高了40.1%,说明改进的蚁群算法能在更短的时间内找到最优解,而且在避免陷入局部最优解方面具有更好的效果。 相似文献
8.
为了提高广播式自动相关监视(Automatic Dependent Surveillance-Broadcast,ADS-B)报文质量,解决由于地面站多重覆盖、硬件设施配置、运行状态等原因引起的报文在数据重复性、数据完整性和实时性上存在的问题,采用多条件直接起始法建立航迹,采用多项约束条件筛选进入优选的报文,并基于专家评级法对报文中表征数据项完整性的权重参数进行估计,结合报文的位置精度和完好性参数综合计算得出ADS-B数据质量指标并将其作为挑选依据。对于ADS-B报文质量极度不理想的特殊情况,使用多重插补(Multiple Imputation,MI)算法对其进行补全处理,综合以上步骤挑选出高质量和高可靠性的ADS-B更新点迹。仿真计算证明该方法可有效剔除重复覆盖造成的重复报文和网络延迟造成的历史数据,防止航迹点回跳,提高数据质量和监视效率。目前,该方法已实际应用于地面站和传输链路条件均不理想的场合,大量实践结果表明该方法可用于保证输出高实时性的、周期性的、稳定平滑的、可靠的ADS-B数据。 相似文献
9.
10.