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为了开发能更细致的模拟集卡行驶方式及特点的新模型,应用元胞自动机理论,建立以单个集装箱卡车车位为元胞个体的集装箱码头前沿交通流二维仿真模型。通过对该模型的仿真试验,证实该模型能输出更接近于现实的仿真数据结果。 相似文献
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LINDe-ming JINHong-zhang LIQi WUHong-mei 《船舶与海洋工程学报》2004,3(2):69-72
Now the research on the complex system is a hot spot. Brittleness is one of the basic characteristics of a complex system. In a complex system, after one of subsystems is struck to be collapsed, the whole system will collapse. Meanwhile, cellular automata is a discrete dynamic system. When the rule is given, the cellular automata could be defined. Then it can imitate the complex action. Cellular automata is used to simulate the brittleness action in this study. Entropy was used to analyze the action and get the rule. Then,three normal brittleness models were given. The result shows that the brittleness of complex system is existent and in addition some important behavior mode of complex system brittleness has been achieved. 相似文献
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Kwang Hyo Jung Kyung Chun Kim Sang Youl Yoon Seong Hun Kwon Ho Hwan Chun Moon Chan Kim 《Journal of Marine Science and Technology》2006,11(4):270-278
Stereoscopic particle image velocimetry measurements were made in a wind tunnel using a prototype waterjet model. The main
wind tunnel provided the vehicle velocity and a secondary wind tunnel was set up as the waterjet propulsion model. Pressure
distributions along the ramp and lip sides inside the duct were measured for three jet velocity to vehicle velocity ratios.
Three-dimensional velocity fields were obtained at the intake entrance and the nozzle exit of the waterjet system. The flow
into the duct was faster in the lip region than on the ramp side. Because of the variation in intake geometry from a rectangular
to a circular section and because of the sudden curvature change on the lip side, a pair of counter-rotating vortices was
observed in the mean velocity field at the nozzle exit. In addition, the turbulent kinetic energy correlated with the vortex
pair was stronger on the lip side than in other areas. Dominant large-scale structures were extracted by using a snapshot
proper orthogonal decomposition analysis. It was found that most of the turbulent kinetic energy was attributed to at least
three vortices near the nozzle exit. This detailed three-dimensional velocity field will be useful for the verification of
CFD simulations applied to the waterjet system. 相似文献
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采用框格结构固土的生态护岸是护岸工程的新趋势,框格固土能力是生态护岸建设成败的关键一环。介绍多宫格块体这种新型的生态护岸六角块体,并通过室内水槽试验研究块体空腔内部泥沙在波浪作用后的侵蚀深度。试验结果表明:斜坡堤上多宫格块体内部泥沙侵蚀深度符合沿堤从上到下先增后减的规律,同时泥沙侵蚀深度会随波高的增大而增大,斜坡堤不同位置以及单个块体不同部位泥沙侵蚀深度不同,改变块体空腔内填充的泥沙类型会影响侵蚀深度但不影响斜坡堤上侵蚀的整体规律。相比于框格栅栏板,多宫格块体具有更好的固沙效果,可以为植物护岸提供良好的生长环境。 相似文献
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用常规方法对双凸极电机空载电磁场进行了计算,提出了双凸极电机电磁场有限元分析方法,应用有限元软件ANSYS对电机的静态电磁场进行了仿真计算。结果表明采用有限元方法仿真的结果和同实际情况基本相符。 相似文献
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通过建立电场在深海环境下的空气-海水两层模型,采用镜像法,得到深海模型中垂直静态电偶极子的电位和电场分布解析表达式,在此基础上,进行电位和三分量电场仿真计算,分析了两层模型下垂直静态电偶极子的电位、电场强度的分布特性,得到它们随海水深度变化的规律。 相似文献
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二次预应力外包钢组合梁叠合楼盖动力特性有限元分析 总被引:1,自引:0,他引:1
二次预应力外包钢组合梁叠合楼盖结构体系是目前在外包钢组合梁和预应力结构理论研究基础上提出的新型楼盖体系。这种新型式的组合式叠合结构利用轻骨料混凝土大幅地减轻结构自重,增加楼盖体系保温隔热和隔音性能,同时通过两次预应力的张拉,使该新型楼盖系统适合了大跨度工程施工及承载,以及充分发挥各组合材料物理力学特性的要求,为该类型结构推广应用奠定了基础。论文采用有限元软件ANSYS建立叠合楼盖三维实体模型。对叠合楼盖的动力特性进行了分析,并通过改变预应力的大小、预应力筋的布筋形态和柱的约束条件等进行参数讨论。文中分析了各参数对结构体系自振频率及振幅产生的影响并得到了一些规律性的结论,对进一步研究该体系的动力性能有一定的指导意义。 相似文献
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钹式水听器体积小,灵敏度高,但其接收性能不够稳定,接收频带较窄.为了克服这些弱点,对其结构进行改进.运用双片陶瓷并联代替单片陶瓷,并缩小陶瓷半径.再通过有限元仿真实验和水池实验,对改进前后的钹式水听器进行测试,结果表明,改进后的钹式水听器接收性能更加稳定,接收频带也明显增加,同时其灵敏度依然较高. 相似文献
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船体结构静动态协同优化设计(英文) 总被引:4,自引:0,他引:4
论文集成静态、模态和动力响应分析,建立了船体结构静、动态协同优化模型.在系统级优化模型中,以单学科最优解和多学科最优解之间的差异最小化为目标.该目标函数不仅消除了多个目标之间的量纲和数量级差异的影响,而且扩展了协同优化算法的应用范围,由原来的单目标优化扩展到了多目标优化.并与子系统级优化模型构成二级协同优化算法架构.采用多岛遗传算法进行优化求解.对集装箱船艉主甲板进行了静、动态优化设计,分析表明本文所采用的优化算法能应用于工程实际. 相似文献
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从元胞自动机的理论入手,阐明多次打击评估的基本依据,并通过仿真模拟计算完成生命力的评估并对评估进行分析和提出改进方法。 相似文献
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文中以同时具有缺席型和遗漏型未知属性值的不完备目标信息系统为研究对象,根据特征关系,研究可变精度粗糙集的模型及其性质.可变精度粗糙集模型与原始的粗糙集模型不同,它是建立在集合多数包含的基础上的,因而该模型是基于特征关系的经典粗糙集模型的推广形式,而基于特征关系的经典粗糙集模型则是可变精度粗糙集模型的一种特殊表现形式.文中对新模型的主要性质作了阐述和证明,结果表明:在不完备目标信息系统中,新模型与原始的粗糙集模型相比具有更高的近似精度,可进行更为精确的度量. 相似文献
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A numerical model was developed for a floating floor with an inserted viscoelastic layer to predict the structure-borne noise
(SBN) in ship cabins. In cabins, high-density mineral wool is usually used as an impact-absorbing material. The theoretical
model consisted of multipanel structures lined with high-density mineral wool. The predicted results for SBN when a floating
floor with an inserted viscoelastic layer is used were compared with the measurements done on a cabin mock-up. Various floating
floors with inserted viscoelastic layer structures were studied, and the effects of variations in the thickness, density,
and fiber direction of the high-density mineral wool were investigated. Comparisons of the predicted results and the experimental
results showed that the developed model could be an effective tool for predicting SBN in ship cabins. 相似文献
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针对船用膜片联轴器的膜片组件螺栓连接的复杂性问题,基于薄层单元法对膜片组件的有限元模型进行简化,提出一种新型简化建模方法——结构分割法。对模型静刚度进行计算,确定结构分割法中结合面单元的弹性模量和泊松比。该方法相较于传统的薄层单元法计算效率更高。将结构分割法模型的模态仿真结果与试验结果进行对比,结果表明,结构分割法模态分析得到的振型与试验测得的前三阶振型吻合较好,固有频率误差均在10%之内,验证简化模型仿真的正确性,可为船用膜片组件结合部动力学快速有效建模提供思路。 相似文献