3D打印在交通工程领域的应用

近几年,由于3D打印技术的快速发展,其应用范围不断扩大,为许多行业的转型升级提供了宝贵的契机。目前3D打印技术广泛应用于航空航天、材料、医疗、汽车、建筑等行业,得到了良好的反馈。因此,研究人员开始关注3D打印是否能与交通工程领域相结合。简单总结了3D打印技术的类型与优势,概述了3D打印技术在桥梁工程、道路工程以及轨道交通（主要为铁道方面）三个领域的应用,指出3D打印技术在这三方面的应用大多处于探索阶段,并对3D打印技术在交通工程领域的应用前景进行了展望。     

舰艇编队远程通信保障系统研究

该文基于现有通信技术手段,从海军舰艇编队未来作战的使命任务出发,提出了海军舰艇编队远程通信保障系统的优化设计方案,在通信保障系统的总体框架下,阐述了海军远程通信保障系统的总体思路和实现方案。     

大体积混凝土配合比设计优化策略

大体积混凝土结构的工程质量控制难度较大。在三亚凤凰岛国际邮轮港二期工程施工过程中,为了确保大体积混凝土结构质量满足设计要求,在大体积混凝土正式施工之前,通过模拟现场工况条件进行大体积混凝土试验块的生产、浇筑、养护,并对试验块的内部温度及应变变化规律进行监测,开展优化混凝土配合比设计的研究。通过两组不同混凝土配合比(水胶比分别为0.38、0.40)同条件下的对比试验得出更优的混凝土配合比。结果表明,水胶比为0.38的混凝土方块的核心区最高温度、最大温升、里表温差、最大降温速率均大于混凝土水胶比为0.40的混凝土方块,建议选择后者进行高温地区大体积混凝土施工。     

基于动态规划的备件多级优化配置

为提高引进装备备件的保障效能,提出一种基于动态规划的备件多级优化配置方法.采用该方法建立备件配置动态规划模型,并利用最优化原理实现备件的多级优化配置,使有限的备件发挥最大的保障效能.通过一个实例给出应用该方法建模的过程并验证了其有效性.     

25型客车制动装置仿真系统的研制

介绍了25型客车制动装置仿真系统的总体设计方案,分析了仿真系统实现的功能及其特点.     

用平衡记分卡确定我国船舶企业的关键业绩指标

我国造船企业已确立了长远发展目标———“五三一”发展目标。其使命应被细划为业绩目标,具体的行为达到业绩目标从而完成使命。财务会计模式不能够评价企业某无形资产(关键成功因素)的价值,但这些关键成功因素对成功的影响远比传统的有形资产大,它们甚至是企业在当今乃至未来的激烈竞争环境中制胜的关键。平衡计分卡强调财务与非财务指标必须是信息系统的一部分。我国造船企业应有效地应用平衡记分管理系统,关注非财务指标的关键成功因素,以面对竞争日益激烈的世界造船业。     

船用光纤陀螺动态建模方法研究

提出了一种基于沃尔什函数(Walsh)的船用光纤陀螺动态建模方法,引入沃尔什函数可直接由光纤陀螺的时域动态标定数据得出其动态模型微分方程或连续传递函数的系数．文章有效解决了沃尔什矩阵的产生、沃尔什变换时信号采样点的选取等问题．仿真及实测数据的研究表明,该方法获得了良好的建模效果,可以应用于建立光纤陀螺的动态模型．     

Breaking wave at the bow of a fast displacement ship model

We investigated the flow structures under the bow wave generated by a fast displacement ship model (INSEAN model 2340) in the presence of wave breaking. The data acquired were also used for a detailed database for CFD validation. The mean and r.m.s. point-wise values of the wave height were measured by means of a finger probe. The intensity of the breaking wave was taken as the r.m.s value of the wave height. The mean velocity field under the free surface was measured at 0.15 L _PP and 0.2 L _PP downstream of the fore perpendicular by means of a 5-hole Pitot probe. Uncertainty assessment of the wave height and velocity field results was performed following the AIAA Standards S-071-1995. Preliminary CFD results from a RANSE code with a breaking model are shown in comparison with the measured data.     

Post OPA-90 vessel oil spill differentials: transfers versus vessel accidents

This study investigates vessel oil spill differentials for transfer and vessel-accident spills for the post Oil Pollution Act of 1990 (OPA-90) period. In-water and out-of-water transfer/vessel-accident oil spill equations are estimated, utilizing tobit regression analysis and data of individual vessel oil spills (of oil-cargo and non-oil-cargo vessels) investigated by the US Coast Guard for the 1991-1995 period. In the data, 47.5% (94.1%) of in-water (out-of-water) gallons of oil spilled were transfer spills; non-oil-cargo vessels accounted for 44.2% of all gallons spilled. The estimation results suggest that out-of-water transfer spills are larger in size than vessel-accident spills, but are similar in size for in-water spills. Transfer/vessel-accident spill differentials exist (do not exist) among determinants of in-water (out-of-water) spills. The policy implication of the results is that a vessel oil spill-reduction differentiation regulatory regime is needed that differentiates between transfer and vessel-accident spills and in-water and out-of-water spills for reducing vessel oil spills.     

柴油发动机燃烧故障排除的几种常用方法

柴油发动机在使用过程中会出现冒出白烟、蓝烟或黑烟等不正常燃烧现象,针对这些现象的形成机理进行分析,并给出了故障排除的方法和对策。