三峡水库变动回水区泥沙冲淤特性分析

依据三峡蓄水后变动回水区的实测资料,初步分析了三峡水库175m正常蓄水下变动回水区输沙过程及该河段冲淤特性,揭示了航道调整的内在机理,总结了水沙条件变化和河段冲淤规律。结果可为减少变动回水区的泥沙淤积及淤沙浅滩的治理提供科学依据。     

软体排护滩带的护滩效果研究

长江中下游心滩河段水沙运动规律较为复杂,碍航问题也较为突出。为了改变这种现状,可采用护心滩建筑物对心滩进行守护,以达到恢复和改善航道条件的目的。以长江中游典型碍航心滩河段——沙市三八滩河段为原型,进行了心滩采用软体排护滩带守护的概化模型试验,结合理论分析,详细论述了软体排护滩前后心滩和河床的冲刷变化规律以及软体排护滩带对汊道分流分沙比的影响。给出了水流挟沙力和动床阻力在心滩河段汊道及滩上的沿程变化规律。对心滩守护前后的水流挟沙力和动床阻力进行了对比分析,并对软体排护滩的整体效果进行了总结。     

一种新型船舶压载水管理系统的设计

本文设计一套压载水管理系统,该系统能方便地进行液位遥测和阀门遥控,友好地实现对船舶压载水的监测和管理。论文介绍了计算机工作站的结构和基于Usual Basic的软件功能．     

三峡库区架空直立墩式码头靠泊能力评估研究

三峡库区正常蓄水后,库区航运条件得到极大改善。由于码头存在靠泊超设计船型船舶的情况,因此,对库区现有码头进行靠泊能力评估是十分必要的。本研究通过分析和研究架空直立墩式码头的靠泊能力,提出结合原有设计和码头实际运行情况,并通过有限元计算分析超设计船型靠泊时码头结构实际响应的综合评估方法。该方法可为类似码头靠泊能力评估提供参考。     

长江中游宜都水道河床演变分析及治理对策初探

通过实测资料,系统分析了长江中游宜都水道演变特点,并重点对三峡蓄水后的演变规律进行了分析,提出初步治理对策。结果表明:宜都水道是长江中游离三峡枢纽最近、受其影响最早的碍航水道,天然情况下属枯季碍航浅水道;蓄水后,水浅的碍航问题得到了一定的改善,但其支汊发展、边滩冲刷现象明显,其对宜昌水位的控制作用受到威胁,因此及时实施该水道控导工程以稳定控制节点作用十分必要。     

基于Arcgis的圩区设计内涝水位计算

南京作为中国东部地区重要的中心城市,市域内地铁线路发达,尤其长江两岸圩区内站点分布较为密集。圩区内涝水位是影响地铁站点布置、设计及施工的重要因子。本文以南京地铁站点所在某圩区为例,将实测地形高程数据导入Arcgis进行三角网格差分处理,生成圩区的水位～调蓄量关系,再通过水文方法计算的内涝水量,查询水位～调蓄量关系,得出地铁设计标准下圩区内涝水位。提供一种内涝水位计算方法,为今后类似工作提供参考。     

Numerical Analysis and Comparison of the Fan Ducted Discharge Equipment Acoustics

In order to cut down excessive experiments, acoustic response of the different fan ducted discharge equipment was studied based on numerical method. The sound pressure level(SPL) in each component of a ductplenum-reverberant room model was drawn and SPL deviation was analyzed. The trends of the curves were explained by the diffracti on and end reflection at the duct discharge. Models with different room dimensions, duct lengths, duct cross sections, duct locations and duct elbow were constructed, and their response was analyzed and compared. The results show that the SPL curves are smooth in the duct discharge cross section, but seriously fluctuant in the reverberant rooms SPL in the duct discharge is only sensitive to duct dimensions, while that of the reverberant room is regularly influenced by all the dimension and arrangement factors. Small room and short duct help to increase room SPL. Elbow has an indistinct influence on all the components‘ sound field. Finally, suggestion to reduce the deviation of experiment results was proposed.     

Wind Vibration Study of Long-span Steel Arch Structure of Beijing Capital International Airport

IntroductionThe long-span light-weight steel arch struc-tures have been widely used in the world due to itsbeautiful shape and reasonable mechanical charac-teristics. With the development of the computa-tional theory, the steel arch span becomes longerand longer. So, the wind loads become the majoror even dominant loads applied on steel arch struc-tural system[1~3]. The distress and damage willprobably occur in the structure, because of thelong term wind-induced vibration.1 Structural Wind-in…     

Agent Technology Application in Automating the Coordination and Decision-Making in Supply Chain

Coordinating all the activities among all the parties involved in supply chain can be a daunting task. This paper put forth the viewpoint of applying agent technology to automate the coordination and decision-making tasks in a typical home PC industry supply chain. The main features of the proposed approach, which differentiate it from other approaches, are the following： ① In the prototype, the coordination agents have both cooperation and competition patterns, ② It uses JADE （Java Agent DEvelopment Framework） as the agent development environment to realize efficient and reusable agent software; ③ It produces some innovative models for the business processes and issues faced by parties in the supply chain. A prototype and the overall process flow were also described.     

浅谈基于流量计量法的船舶液舱容量计量系统

针对舰艇液舱舱室普遍具有空间小,结构复杂的特点,本文采用高精度流量计配合高精度液位传感器的方法,设计出一套基于容量比较法的液舱计量系统,简要介绍了主要原理、工作流程、结构特点和功能以及达到的技术指标,该系统具备自动化程度高、计量精度准确、工作时间短等优点。