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1.
A novel image sequence-based risk behavior detection method to achieve high-precision risk behavior detection for power maintenance personnel is proposed in this paper. In this method, the original image sequence data is first separated from the foreground and background. Then, the free anchor frame detection method is used in the foreground image to detect the personnel and correct their direction. Finally, human posture nodes are extracted from each frame of the image sequence, which are then used to identify the abnormal behavior of the human. Simulation experiment results demonstrate that the proposed algorithm has significant advantages in terms of the accuracy of human posture node detection and risk behavior identification.  相似文献   
2.
以漳州市某超高层项目为例,针对超高层密集布筋区埋入式型钢柱脚与钢筋的深化设计、地脚螺栓的定位预埋、型钢柱脚支撑体系设计、节点钢筋穿插连接施工、埋入式型钢柱脚安装等方面,提出切实可行的施工方法,解决了埋入式型钢混凝土柱脚的地脚螺栓精准预埋、与底板密集钢筋穿插连接施工、悬空支撑稳定等一系列施工技术难题,既满足了设计方案的要求,又可为类似工程提供借鉴。  相似文献   
3.
针对货运车辆在配送调度过程中产生大量碳排放的问题,建立模型将多种影响碳排放量的因素协同优化。模型中考虑了不同载重量的异质车队,两个节点之间有多条道路的柔性路径,以及车辆重量随卸货而减少的动态负载等因素,以碳排放量、行驶时间和行驶路程为优化目标,并加入了节点需求时间窗、根据速度变化划分路段、交接和卸货时间的约束。提出了一种混合蚁群算法,利用蚁群算法信息素强度更新方式保持群体记忆性,利用粒子群算法的快速收敛特性增加计算效率。通过随机数值算例的仿真优化与对比分析,验证了算法和模型的有效性。  相似文献   
4.
The operational planning of distribution network for automotive industry is complex with many conditions to consider, including heterogeneous fleet, enforcing the feasibility of 3D-packing of pallets into vehicles to address the vehicle's capacity in terms of weight and volume, compatibility of orders in a vehicle, returning empty pallets from assembly-plants backwards to suppliers, and delivery time windows. A mathematical model (MILP) is proposed that takes account of these conditions to minimise total transportation costs. The network structure can be a combination of direct shipment and milk-run for both forward and reverse flow of pallets. The model is solved optimally for small-size problems. For solving larger problems, a heuristic algorithm (in two versions) is proposed that uses a similarity measure to generate a reasonable list of orders. Best/first-fit strategies are employed to generate a feasible solution with the aid of a relaxed version of the proposed MILP. Improvement heuristics are also designed. Unlike most of existing constructive heuristics, our aim for developing the heuristic approach is to force routing decision, with all of its considerations, being made optimal. We also use the proposed best-fit strategy in the body of grouping evolution strategy (GES) algorithm to attain an effective meta-heuristic approach. The effectiveness of heuristics is tested on generated instances which demonstrates they are optimal for small-size problems. They are also tested on the data of daily auto-parts shipments gathered from the largest Iranian automobile company. Results demonstrate there exists a significant potential for cost saving through milk-run strategy compared with the direct shipping strategy.  相似文献   
5.
The airline industry is a representative industry with high cost and low profitability. Therefore, airlines should carefully plan their schedules to ensure that overall profit is maximized. We review the literature on airline planning and scheduling and focus on mathematical formulations and solution methodologies. Our research framework is anchored on three major problems in the airline scheduling, namely, fleet assignment, aircraft routing, and crew scheduling. General formulation, widely used solution approaches, and important extensions are presented for each problem and integrated problems. We conclude the review by identifying promising areas for further research.  相似文献   
6.
摘要:针对水下无线传感网络中运动节点定位精度低的问题,提出了一种新的基于双层修正无迹卡尔曼的水下节点定位算法(DLMUKF)。该算法利用下层无迹卡尔曼滤波算法对节点状态进行预测,根据各信标节点的测距传播时延对预测的节点状态进行修正。运用上层无迹卡尔曼滤波算法对修正后的状态进行新的预测与修正。仿真实验中,DLMUKF算法的平均定位误差约为传统多边定位算法的15%,约为基于无迹卡尔曼滤波(UKF)定位算法的16%,受节点运动时间与速度的影响最小。通过实验证明DLMUKF算法能更充分利用实际距离值,可以有效减小运动节点的定位误差。 .txt  相似文献   
7.
We propose in this paper a Hybrid Software‐Defined Networking‐based Geographical Routing Protocol (HSDN‐GRA) with a clustering approach. It takes into account three different criteria to select the best relay to send data: (1) the contact duration between vehicles, (2) the available load of each vehicle, (3) and the log of encountered communication errors embedded in each cluster head. The multi‐criteria strategy allows the selection of the most reliable vehicles by avoiding communication problems and ensuring connection availability. Once the hybrid control plane has found out the next eligible neighbor, the data plane will be in charge of dividing and sending data. To validate our approach, HSDN‐GRA has been modeled and implemented in JADE, a multi‐agent platform, to be compared to other multi‐agent based protocols. Simulation results show that HSDN‐GRA achieves good performance with respect to the average routing overhead, the packet drop rate, and the throughput.  相似文献   
8.
This paper introduces a new integrated multi-factory production and distribution scheduling problem in supply chain management. This supply chain consists of a number of factories joined together in a network configuration. The factories produce intermediate or finished products and supply them to other factories or to end customers that are distributed in various geographical zones. The problem consists of finding a production schedule together with a vehicle routing solution simultaneously to minimise the sum of tardiness cost and transportation cost. A mixed-integer programming model is developed to tackle the small-sized problems using CPLEX, optimally. Due to the NP-hardness, to deal with medium- and large-sized instances, this paper develops a novel Improved Imperialist Competitive Algorithm (IICA) employing a local search based on simulated annealing algorithm. Performance of the proposed IICA is compared with the optimal solution and also with four variants of population-based metaheuristics: Imperialist Competitive Algorithm, Genetic Algorithm, Particle Swarm Optimisation (PSO), and Improved PSO. Based on the computational results, it is statistically shown that quality of the IICA’s solutions is the same as optimal ones solving small problems. It also outperforms other algorithms in finding near-optimal solutions dealing with medium and large instances in a reasonably short running time.  相似文献   
9.
何云华  牛童  刘天一  肖珂  芦翔 《计算机应用》2019,39(5):1385-1388
针对网络扫描工具在进行扫描时面临的溯源问题,提出了一种匿名网络扫描系统。首先将匿名系统与网络扫描工具结合以实现匿名扫描;然后在现有匿名系统的基础上实现了该系统的本地私有化;接着通过流量分析发现,Nmap的多进程扫描因为代理链的原因会变成单进程扫描而导致其扫描扫描性能较低;最后提出了一种基于多Namp进程并发的性能优化方案,将总体扫描任务分割为多个扫描任务,并分配给多个单独的Nmap进程并行运行。实验结果表明,该性能优化方案的扫描时延接近正常扫描情况下的时延,达到了提高匿名扫描系统性能的目的。因此,该优化后的网络匿名扫描系统在阻碍溯源的同时提升了扫描效率。  相似文献   
10.
对一种外LET柔顺半铰进行建模与动力学特性分析。采用斜率不连续的绝对节点坐标法(ANCF)建立了该柔顺半铰系统动力学方程;对外力作用下半铰中心线和外轮廓的运动变形进行仿真,与实验结果对比,证明了绝对节点坐标法对柔顺半铰动力学建模的有效性;进一步分析了半铰外形尺寸变化对其变形规律的影响。  相似文献   
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