Disaster prevention and strategic investment for multiple ports in a region: cooperation or not

With the growth of maritime transportation, seaports have become critical to the world economy as linking nodes between shipping and inland transport. However, the port system is fragile under certain unconventional emergency events. This study addresses the issue of investment on disaster prevention within the port competition context. The present model discusses and compares four situations of different relationships and strategies of pre-disaster prevention between two adjacent ports. Results indicate that both ports increase the disaster prevention investment under the cooperation scenario compared with that in the case of non-cooperation wherein they are complementary ports. Meanwhile, a numerical simulation is conducted to examine the collective and individual rationality of both ports. Although cooperation strategy decreases the total risk cost of two ports, one of the two ports may profit, whereas the other may suffer losses.     

Effect of Seismic Parameters on the Safety Factor for an Underground Cavern北大核心CSCD

In order to quantitatively evaluate the safety of the surrounding rock of an underground cavern under seis-mic load, a comprehensive evaluation method for the stability of surrounding rock is proposed based on the general safety factor and point safety factor. A calculation method for the general safety factor of a cavern based on the prin-ciple of shear strength reduction of a rock mass is given, the run-through of the plastic zone between the main power-house and main transformer room is presented as a critical criterion for the overall instability of the cavern, and the general safety factor is obtained by searching for the reduction coefficient. A point safety factor calculation method based on the Mohr-Coulomb yield criterion is given. The influence of different seismic input parameters on the general safety factor of the cavern and the point safety factor of key positions are studied based on an underground power-house cavern of a hydropower station in Southwest China. The results show that the quantitative evaluation method for the stability of the surrounding rock based on the safety factor is feasible and can reflect the general safety de-gree and local safety degree of different positions of the cavern for different working conditions. It is found that the general safety factor of the cavern and the point safety factor of key positions decrease with an increase of the ampli-tude and duration of a seismic wave while they increase with an increase of the incident angle; additionally, the low frequency of a seismic wave has a great influence on the cavern while the high frequency has little effect. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

洋山深水港西港区岸线功能规划调整

为满足洋山深水港生产营运需要,有关部门希望保留颗珠山—蒋公柱潮流汊道,这与总体规划布置不一致。为此需进行深水港西港区岸线功能规划调整研究。考虑到汊道的颗珠山一侧潮流具有岬角绕流型特点,而蒋公柱一侧有岬角环抱型特点;在此认识基础上针对多种岸线方案进行试验。试验结果表明,采用岸线优化方案后,可以保持甚至改善汊道内和已建港区潮流条件。从水流角度看,采取合理的岸线布置和适当的工程措施后,保留和开发利用颗珠山—蒋公柱潮流汊道是可行的。     

复合动力超长续航无人艇系统的设计与实现

为实现无人艇在海上追踪、搜救、巡逻、反潜等任务中的超长续航,避免因油料限制而被迫任务中断,设计了一套以风能、太阳能为动力的无人艇系统,利用风帆为无人艇推进,太阳能为船上电控设备提供电能。该系统由无人艇和岸基监控平台组成,无人艇可通过python开发的数据采集模块和算法模块实时采集环境数据、计算、生成并下达控制指令,在风区内可超长续航自主航行,实现全风向利用;岸基监控平台可实时监控无人艇状态,并进行自主/遥控模式切换。对系统进行了测试,通讯连接试验的可靠性高;无人艇航行试验验证了全风向自主航行的可行性,运行轨迹与仿真结果基本重合;太阳能供电分析理论上验证了风区超长续航的可实现性。     

含锂电池储能的船舶电力系统模型预测控制研究

由于船舶运行的特殊性和负载波动的复杂性,严重影响船舶电力系统的稳定性,因此引入了能量存储技术,降低电网的波动。根据发电机和锂电池的状态空间模型,建立了含锂电池储能的船舶电力系统,并提出了一种基于模型预测控制的船舶电力系统。在含有负载波动的情况下,使发电机和锂电池的输出能够稳定跟随负载的变化,从而满足负载的需求。并将整个系统在Matlab/Simulink中进行实例仿真,仿真结果表明,在模型预测控制下的船舶电力系统能够很好地满足负载波动需求,明显改善船舶电力系统的稳态性能,增强船舶电网的稳定性。     

一种用于高压脉冲电容实验平台的充电电源模块设计

本文是对一种用于高压脉冲电容实验平台的充电电源模块的设计进行论述。主要介绍该充电模块在高压脉冲电容实验平台中的功能、作用、技术要求。论述了充电模块中交流变换单元的电路,对高频变换单元的功能实现进行了阐述。     

铝合金耐压结构设计分析与试验验证

根据水下潜器总体性能要求,按照最小重量原则,结合规范和有限元方法设计工作潜深为500m的铝合金带加强筋形式的圆柱耐压舱,并通过压力筒加压试验,对Ansys有限元静力分析的精确度进行了验证,为耐压结构设计与校核提供重要参考.     

“UD—63”尼桑40吨半拖挂 车的改造

介绍了“ＵＤ－６３”尼桑４０吨半拖挂车更新改造、废物利用的全过程,并对动机更新、传动系统配置,供气及冷却系统改装等技术问题进行了详细论述。     

桥墩防撞装置碰撞动力学分析

运用非线性有限元基本理论，采用国际上广泛使用的大型结构分析程序LS-DYNA，建立了船舶和桥墩防护装置的三维有限元计算模型，分析了防护装置碰撞特点、船首及构件的损伤和吸能特性，得出了主要吸能结构吸能比例，碰撞力曲线的非线性特点，船体和防撞装置外板是主要的吸能结构等结论．     

静压PTC管桩施工技术

本文根据沪宁高速公路扩建工程HN—D1—1标静压桩的施工实践,对静压胛c桩施工原理、主要施工技术作一介绍,供同类工程借鉴参考。