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991.
992.
Abstract

the prospect of global warming and consequent sea level rise will have important implications for coastal communities. this article examines the land use implications of alternate sea level rise scenarios on the city of myrtle beach, south carolina. current trends as well as high and low sea level rise scenarios are superimposed on the city's beach profile and near shore contours to estimate the type and value of land development likely to be impacted.

It is found that losses associated with accelerated sea level rise would be particularly high in the city's hotel district and that overall property loss could range from 21 to 60% of the city's total property value. to lessen these potential losses, coastal communities such as myrtle beach must choose among one of three policy options including: (1) barricade the beach, (2) raise the land, and (3) implement a strategic retreat. specific alternatives within each of these options are explored in turn. the article concludes that successful development plans will incorporate ground rules sensitive to and consistent with dynamic coastal processes.  相似文献   
993.
杨立波 《船舶工程》2013,35(2):19-21
为适应海上交通安全管理需要,确定巡逻和救助船舶配置规模,根据船舶使用水域和功能定位,将巡逻和救助船舶划分3种类型和7个系列,基于巡逻船雷达基本探测原理和巡逻路径,计算巡逻船有效监管距离和面积,基于海上交通应急到达时间要求和救助路径,计算救助船有效救助距离和面积,根据离岸不同距离水域面积和岸线长度,确定巡逻和救助船舶配置规模,提高巡逻和救助船舶布局规划的科学性。  相似文献   
994.
对国内若干开敞海域码头泊位长度进行分析,又对英、美、日本及石油公司国际论坛等现行港口工程规范中开敞式码头泊位长度的确定方法进行讨论。在此基础上指出:开敞海域液体散货码头的横向约束比纵向约束更为重要;在不影响船舶约束效果的前提下,采用较大水平系缆角以及适中的缆绳长度可有效缩短泊位长度;并建议对于单个独立的开敞式液体散货泊位,其泊位长度可按1.1~1.3倍设计船长确定。  相似文献   
995.
李伟  张宝航 《水运工程》2013,(8):160-164
根据船闸下引航道口门区水流特点,应用水槽数学模型,对不同引航道宽度、水流流速、水深等对下引航道口门区回流长度等特性的影响进行研究,得出船闸下引航道口门区回流长度的计算公式,并通过概化模型研究透空隔流堤对下引航道口门区水流条件的影响,结论可供船闸工程设计参考。  相似文献   
996.
本文在前人对海浪理论研究的基础上,对我国浅水区海浪谱模型进行了仿真分析,初步研究了浅水区海浪波动对电磁浮标姿态变化的影响,建立了浮标姿态横滚角θ随海浪波动的变化模型,并通过对不同海况级下的θ变化规律进行了matlab仿真分析,说明了模型建立的正确性.  相似文献   
997.
影响高速公路服务区建设项目造价的因素很多,如何从决策阶段、设计阶段、招投标阶段、施工阶段等环节对工程总造价进行有效控制,从而提高服务区的社会效益和经济效益,值得工程建设者思考.  相似文献   
998.
针对南海海域环境荷载下服役的固定式平台,以一固定式导管架平台为例,运用基于ANSYS软件的单元替换法分析计算该平台无缺陷情况下和有腐蚀、海生物附着、构件缺失等损伤情况下的极限承载能力,验证了计算正确性和可行性.  相似文献   
999.
Small water-plane area twin-hull(SWATH) has drawn the attention of many researchers due to its good sea-keeping ability.In this paper,MMG's idea of separation was used to perform SWATH movement modeling and simulation;respectively the forces and moment of SWATH were divided into bare hull,propeller,rudder at the fluid hydrodynamics,etc.Wake coefficient at the propellers which reduces thrust coefficient,and rudder mutual interference forces among the hull and propeller,for the calculation of SWATH,were all considered.The fourth-order Runge-Kutta method of integration was used by solving differential equations,in order to get SWATH's movement states.As an example,a turning test at full speed and full starboard rudder of ‘Seagull' craft is shown.The simulation results show the SWATH's regular pattern and trend of motion.It verifies the correctness of the mathematical model of the turning movement.The SWATH's mathematical model is applied to marine simulator in order to train the pilots or seamen,or safety assessment for ocean engineering project.Lastly,the full mission navigation simulating system(FMNSS) was determined to be a successful virtual reality technology application sample in the field of navigation simulation.  相似文献   
1000.
Abstract

This paper presents a decision support methodology for long-range planning of transport systems that exhibits strategic flexibility and stochastic system parameters. Unlike one-off strategic decisions, flexible decisions should be dynamically reformulated with time. The proposed methodology is based on the construction of a tree structure of multiple interlinked tactical planning problems, each associated with a scenario in the tree, where problems under scenarios at intermediate dates incorporate in their formulation the solution of the corresponding problems associated with past (future) connected scenarios. The resulting tree structure of interconnected planning decisions becomes a strategic-tactical decision support system that allows managers to formulate suitable flexible strategic decisions that mitigate the consequences associated with downside scenarios while taking advantage of the upside opportunities. The methodology is applied to the planning of a fleet deployment through charter contracts where contract prices depend on both market behavior and the duration of the contract itself.  相似文献   
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