基于风险三维结构的大型油轮监管集成

大型油轮运输属于危险品运输,其生产作业具有高危特性.在大型油轮航行和生产作业全过程中会面临从宏观到微观的多层次风险,对通航安全构成潜在威胁.借鉴某三维结构和集成企业工程思想构建大型油轮风险集成管理的三维结构模型,将多层次的风险管理归并到三个维度(功能域、时间域及对象域),以风险三维结构为基础,探讨风险管理集成的主要构成,提出了大型油轮风险管理集成的基本模型和系统监管模式,为相关海事部门监管大型油轮航行及生产作业提供参考依据与决策支持.     

新型开孔工字板组合式透空防波堤消浪特性数值模拟研究（英文）

Based on the three-dimensional Reynolds-averaged Navier-Stokes equation with the closure of renormalization group k-εturbulence model and volume of fluid method, a wave-breakwater interaction numerical flume was developed to examine the wave-structure interaction of the porous I-type composite(PITC) breakwater. The transmission and reflection coefficients of the breakwater at different wave steepness H/L are quantitatively analyzed, and the wave-dissipating performance of the breakwater is compa...     

基于红外图像的助降运动参数测量研究

文章提出了飞机着陆(着舰)光测引导新体制与新方法,通过机载摄像机对红外特征点的提取,用光测图像技术实时测量飞机着陆(着舰)过程的三维轨迹、速度和姿态,解决了飞机着陆、着舰运动参数实时测量的难题。     

On the role played by turbulence closures in hull shape optimization at model and full scale

 The practical use of automated computational fluid dynamics (CFD)-based design tools in the ship-building industry requires powerful flow solvers which are able to take into account realistic geometries as well as complex physical phenomena, such as turbulence. A shape optimization tool is developed in this framework. A derivative-free optimizer, yielding both flexibility and robustness, is preferred to the classical gradient-based method, which is more difficult to implement and is still limited to only moderately complex problems. The flow solver included in the design procedure solves the incompressible Reynolds-averaged Navier–Stokes equations on unstructured grids using a finite-volume formulation involving several near-wall low-Reynolds-number turbulence models. The design tool is used to optimize the stern of a modern hull shape at model and full scale, with different purposes being considered. More precisely, the drag reduction and the homogenization of the flow in the wake are expected by controlling the longitudinal vortex generated. Our interest is particularly focused on the influence of turbulence modeling in the design process. The effects of a two-equation model based on the eddy-viscosity assumption and a second-order closure relying on the Reynolds stress transport equations are compared. Received: September 24, 2002 / Accepted: April 14, 2003 RID="*" Acknowledgment. The authors thank the scientific committee of CINES (project dmn2050) for the attribution of CPU time.     

公路沥青路面水损坏的形成及防治对策

沥青路面的水损坏是目前国内外普通存在的路面破坏形式,成为困扰公路工程质量的世界性难题。文中分析了沥青路面水损坏的主要现象及原因,提出了预防沥青路面水损坏的对策。     

关于航道整治工程中潜孔钻机性能改进的探讨

随着航道整治工程水下爆破施工任务的增多,对提高施工效率及降低成本控制的要求也愈来愈高;遵循经济实用的原则,对原有落后设备进行再次改造是势在必行的举措;改造后的施工效率明显提高和施工成本明显降低,设备的使用寿命得到延长。     

信息工程项目监理相关问题探析

本文首先介绍信息工程及信息工程监理的概念及其特点,在此基础上,指出了信息工程监理的中心工作就是进行信息工程项目的三大目标,阐述了信息工程监理的目标控制及其控制流程。     

基于代价函数的红外多目标跟踪方法

针对复杂背景环境下的红外多目标跟踪问题,文章在已获得各多目标初始信息和观测信息的基础上,采用极坐标数据进行数据关联和滤波,提出了一种基于代价函数的红外多目标跟踪算法,通过确定红外多目标跟踪起始和终结以及后续帧处理技术,实现了不超过48批红外多目标的实时跟踪。仿真实验结果表明,该算法在运动的红外多目标检测效果、跟踪稳定性和实时性方面都有良好的性能。     

虹桥枢纽与虹桥商务区十年交通发展回顾

上海市虹桥综合交通枢纽和虹桥商务区的规划、建设与运营具有示范意义.通过回顾二者的交通发展历程、交通需求、交通状况与当前交通矛盾,判断未来虹桥综合交通枢纽及虹桥商务区发展趋势.对虹桥高铁站线路过于集聚、商务区发展预见不足规划滞后、商务区核心区设置大型会展中心等造成的问题进行反思.总结虹桥综合交通枢纽及虹桥商务区的成功经验...     

Radiosensitivity of β-elemene on rabbit VX2 renal transplant carcinoma model

Objective To investigate the effects of low dosage of β-elemene on the radiosensitivity of rabbit VX2 renal transplant carcinoma model. Methods We took the rabbit VX2 renal transplant carcinoma as the model. Experimental rabbits were divided into three groups: the control group, the radiation group, and the radiation +β-elemene (radiosensitivity) group. The change of tumor was observed by Spiral CT and B ultrasound to compare its regrowth period. The tumor was measured by light microscopy and electron microscopy. Results The tumor in radiosensitivity group was restrained obviously and the sensitization enhancement ratio (SER) of β-elemene was 1.89. Different apoptosis was observed under transmission electron microscopy. Conclusion Low dosage β-elemene can enhance the radiosensitivity of rabbit VX2 renal transplant carcinoma model and induce the apoptosis of tumor cells, but the mechanism needs further study. It promotes apoptosis in mechanisms in vitro.