离散时间窗下集卡数量动态优化研究

对时间窗进行了离散化,加入集卡资源的动态使用和释放,在此基础上建立数学模型对集卡数量的配置问题进行了优化研究。通过数值仿真实验,求得了在各种任务数量下所需的最小集卡数量,并对各种情况下的集卡数量进行了对比分析,得到与实际情况一致的结论。结果表明,该模型较好地解决了时间窗下集卡数量最小化问题,为港口管理者进行决策提供了支持。

考虑翻箱的场桥调度和提箱集卡数量的集成优化

在集装箱码头的进口箱堆场中,码头预约机制、待提箱的实时位置和场桥作业调度方案是制约堆场作业效率和堵塞情况的关键。为缓解进口箱堆场的拥塞情况并提高作业效率,在固定的预约时段内,考虑实时压箱量最少的翻箱规则,兼顾场桥间不可跨越和保持安全间距等现实约束,以场桥最长完工时间最小为目标,构建数学优化模型,设计了嵌入修复算子的改进遗传算法用于求解;通过算例实验验证了算法的有效性和方案的优越性,可为堆场实际作业提供决策参考。

太仓港集装箱码头四期工程翻箱率和集卡数量仿真分析

为了评估集装箱码头平面布置和装卸工艺方案,为规划设计提供决策依据,采用witness仿真方法对集装箱码头整体设计进行优化。以太仓港集装箱码头四期工程为对象构建其整体仿真系统,设置相应仿真条件和参数,用来模拟集装箱船到港靠离泊、装卸船、水平运输、堆场作业等方面的动态过程。根据仿真结果,对港区道路交通流量、通过能力等重要参数进行综合分析和评定。结果表明,当码头翻箱率越高,则码头整体通过能力越低,集卡在堆场内平均滞留时间越长,集卡排队情况就越明显。当每台岸桥配置集卡数量由4辆增加至5辆时,此种配置情况对陆侧装卸效率基本无影响,但对海侧装卸效率增加明显,因此岸桥数量与集卡数量以1:5配置是较优方式。

Investigate the nonuniformity of low-energy electron beam with large cross-sections

Over the past decades, low-energy electron accelerators have been used worldwide for surface curing and sterilization. The beam nonuniformity is an important parameter of the low-energy electron beam with large cross-sections. A simple and accurate measurement system of nonuniformity for the low-energy electron beam with large cross-sections was developed. The main concept consists in the measurement of nonuniformity, which is realized by using a linear actuator to drive two scanning wires through the beam's cross-sections at a fixed speed. The beam distribution can be obtained by sending/collecting the current signals to/from the Data Acquisition (DAQ) software on a laptop by a USB DAQ card. This device is very convenient for the performance testing of a new accelerator at the manufacturer's site. The distribution of the homemade low voltage electron accelerator EBS-300-50 was measured and evaluated.