基于Markovian切换的时滞回归神经网络Lagrange全局均方指数稳定

对一类激励函数是Lurie型（包括有界和无界激励函数）的具有Markovian切换的时滞回归神经网络的Lagrange全局均方指数稳定性进行了研究,得到了回归神经网络在Markovian切换状态下的Lagrange全局均方指数稳定的充分判据,并通过数值例子验证了所得结论的正确性和有效性.     

划拨土地使用权入市增值测算方法探讨——以山东省龙口市东城区为例

在划拨土地使用权入市增值分析和测算方法研究的基础上,以山东省龙口市东城区为例,按类型、用途及区位测算划拨土地使用权以不同用途入市的增值。研究结果表明:龙口市东城区划拨土地入市平均增值率为26.61%。征收农用地形成的新增划拨土地入市增值最大,增值率达142.69%,其次是存量公共用地和工业用地,征收宅基地形成的新增划拨土地、存量商业和住宅划拨用地入市增值平均为负值;总体上高级别增值大于低级别,划拨土地入市转为商业用地增值最大,而转为工业用地增值平均为负值;存量工业、公共划拨土地及宅基地入市转为商住用地是可能的,也是经济的。     

基于 ArcSDE 的版本管理实现基础测绘的增量更新

利用增量更新技术对基础地理信息数据库进行更新是减少工作量、提高更新效率的主要解决方法之一。ArcSDE版本机制可以实现增量数据的提取,但版本冲突的存在制约了该技术的发展及应用。研究自动解决冲突方法,实现对基础测绘数据的增量更新。     

Fully Coupled Fluid-Structure Interaction Model Based on Distributed Lagrange Multiplier/Fictitious Domain Method

This paper,with a finite element method,studies the interaction of a coupled incompressible fluid-rigid structure system with a free surface subjected to external wave excitations.With this fully coupled model,the rigid structure is taken as "fictitious" fluid with zero strain rate.Both fluid and structure are described by velocity and pressure.The whole domain,including fluid region and structure region,is modeled by the incompressible Navier-Stokes equations which are discretized with fixed Eulerian mesh.However,to keep the structure's rigid body shape and behavior,a rigid body constraint is enforced on the "fictitious" fluid domain by use of the Distributed Lagrange Multiplier/Fictitious Domain(DLM/FD) method which is originally introduced to solve particulate flow problems by Glowinski et al.For the verification of the model presented herein,a 2D numerical wave tank is established to simulate small amplitude wave propagations,and then numerical results are compared with analytical solutions.Finally,a 2D example of fluid-structure interaction under wave dynamic forces provides convincing evidences for the method excellent solution quality and fidelity.     

海上溢油粒子追踪预测模型中的两种数值方法比较

在海上溢油粒子追踪预测模型中,关键的是对拉格朗日微分方程的求解。本文首先通过数值实验比较了欧拉法和龙格-库塔法求解拉格朗日溢油轨迹微分方程的优劣,然后将其应用到2005年4月3日发生在大连附近的“ARTEAGA”油轮溢油事故的油膜粒子追踪模型中。数值实验和应用结果表明,在近岸不均匀流场下,用龙格-库塔方法解拉格朗日油粒子微分方程比用欧拉法求解精度高,用龙格-库塔方法模拟“ARTEAGA”油轮轨迹及其扩散范围与实际观测更为接近,而用欧拉法模拟溢油扩散的面积偏大。     

重力卫星加速度数据的插值算法研究

阐述拉格朗日插值法和牛顿插值法的原理,详细地推导其一次、二次微分通用公式,并分别利用推导出来的微分公式对卫星星历模拟数据进行了相应的插值计算,得到对应的卫星加速度数据。通过比较不同公式的计算结果,验证一次、二次微分公式的正确性,并得到一些有益的结论。     

长江上游夏季径流量年际增量预测模型及检验

基于1980-2020年长江上游夏季径流量、降水和气温等资料,采用小波分析、最优子集回归等方法,分析径流量、降水量和气温的变化关系,探讨引发径流量变化的前兆气候异常信号,并构建径流量年际增量预测模型.结果 表明:径流量多寡直接取决于流域总降水量,两者表现出显著的准两年周期振荡特征,年际增量之间的相关系数(TCC)为0....     

基坑降水总应力变化时有效应力增量和沉降量计算

针对基坑降水引起地面沉降计算值比实际值偏大的情况，本文系统分析了潜水和承压含水层在降水后，不同条件下土中总应力及有效应力的计算。基坑降水后土体中的总应力不是通常认为的一成不变。特别是基坑降水中常遇到的降低潜水含水层水头的情况，总应力是减小的，有效应力增量值也小于孔隙水压力下降值。对比分析了通常采用的不变原理和本文提出的可变原理两种情况，降水后土体总应力和有效应力增量计算值有差异，采用分层总和法计算了基于两种原理的沉降量。潜水含水土层沉降量计算偏差最大，基于总应力不变的沉降量比总应力可变的计算沉降量约大20%。本文计算原理对于抽取深层承压地下水导致地面沉降同样适用。     

Understanding size and boundary effectsin scaled model blasts - plane problems

This contribution addresses model blasting and focuses on size and boundary effects on wave propagation, fracture pattern development and fragmentation in small scale laboratory size specimen. Small cylindrical specimens are centre-line loaded by linear high velocity of detonation explosive charges and detonated.

Using elastic wave propagation theory and fracture mechanics it is shown that the type of boundary conditions which prevail at the outer boundary of the cylinder control the extension of bore-hole cracking and fragmentation within the body of the cylinder. In the case of a composite cylinder with dissimilar mantel and core materials, the level of fracturing and fragmentation is controlled by the delamination of the interface. This, in turn, depends on the relative diameters of the core and the mantel. The most important parameter though is the ratio between the length of the pulse (space-wise or time-wise) and the characteristic dimensions of the models, i.e. in this case the diameters of the core and the mantel.

The theoretical basis for a simplified two-dimensional plane treatment is developed. Simple or composite, thin, plate-like specimens are centrally loaded; whereas the core is always a circle, the mantel can be either a circle or a square.     

包体模型应力集中的定量研究

本采用二维弹性介质圆形包体模型,运用连续介和学理论求解出包体内外的应力场、位移场、平均应力、最大剪应力以及能量密度的解析解,从而讨论了硬、软件包体的应力集中特征;