两层流体界面内波的色散和非线性特征研究

色散和非线性是两层流体界面内波的两个重要特性，对其的研究，不仅有助于揭示两层流体界面内波的生成、演化、衰减、消亡机理，而且对水底及沿岸工程具有现实的指导意义。 通过引入描述非线性和色散的两个小参数，考虑了无旋、无粘、不可压两层流体的界面内波。首先，分别用未扰动面速度、任意水深处速度和平均速度推导出两层流体界面波的高阶Boussinesq方程，所得到的方程不仅包括了前人关于两层流体界面波的结果，而且可以退化到表面波的许多情况。随后，分析了用任意水深处速度表示的方程的色散性、非线性特征和浅化因子。结果表明，通过选择适当的和位置有关的无量纲参数，尽管刻画色散性小参数量阶保留到低阶，所获得的结果足可与原始方程的色散性、非线性特征和浅化系数保持很好的吻合。接着，对用平均速度表示的方程和用任意水深处速度表示的方程进行了改进，改进后方程的色散性有了很大的提高。最后建立了包括均匀流、均匀剪切流和泊肃叶流等背景流下的界面波运动的高阶Boussinesq方程，求得了均匀流和剪切流情况下方程的二阶Stokes解，揭示了波流之间和界面波之间的非线性相互作用特性。

基于关系模型的含空值关系数据库的数据更新

本文以空值的完全语义为基础，以空值环境下基于５值（５ＶＬ）的选择运算为工具，深入研究了基于关于模型的含空值关系数据库的数据更新策略和实现算法

企业经营系统的对象模型──资金流模型

本文阐述了大型工业企业综合自动化系统体系结构中经营管理层的对象模型（资金流模型）。首先论述了该模型在自动化体系结构中的地位和作用，然后分析了企业生产经营过程中发生的资金流，提出用借贷流程图方法表达资金流模型，并将这一方法与国际通用的借贷记帐法相联系，从而揭示了资金流模型与会计核算的内在联系．本文还对企业生产与经营活动的几个主要过程用借贷流程图进行了细化描述。

空值环境下关系数据库的更新 Ⅰ：扩展关系模型及基本运算

本文从空值语义及更新操作的关系出发，提出了一种新的扩展关系模型，用以组织更新操作下的含有空值的关系数据库中的信息．同时，定义了这种模型下的基本关系代数运算．为实现空值环境下关系数据库的数据更新奠定了基础。

不同基板预热温度对激光金属沉积成形过程温度场的影响

为降低成形过程的热应力,抑制成形过程裂缝的产生,减小成形过程试样和基板的翘曲变形,激光金属沉积成形往往需要进行基板预热,因此研究不同基板预热温度对激光金属沉积成形过程温度场的影响具有非常重要的意义.根据有限元分析中的"单元生死"技术,利用APDL编程建立了基板预热对激光金属沉积成形过程温度场影响的三维多道多层数值模拟模型,详细分析了基板未预热和分别预热到200,300,400,500,600℃时对沉积成形过程温度场和温度梯度的影响.通过中国科学院沈阳自动化研究所自行研制的激光金属沉积成形系统和基板预热系统,在与模拟过程相同的参数下,利用镍基合金粉末在基板未预热和分别预热到300,400,500,560℃时进行了成形试验,试验结果跟数值模拟结果吻合较好.

不同基板预热温度对激光金属沉积成形过程热应力影响的研究

研究不同基板预热温度对激光金属沉积成形过程热应力的影响,对于降低成形过程的热应力,抑制成形过程裂缝的产生,减小成形过程试样和基板的翘曲变形具有非常重要的意义。根据有限元分析中的"单元生死"技术,编程建立了基板预热对激光金属沉积成形过程热应力影响的三维多道多层数值模拟模型,详细分析了基板未预热和分别预热到200℃、300℃、400℃、500℃、600℃时对沉积成形过程VonMise’s热应力、X方向、Y方向以及Z方向热应力的影响。在与模拟过程相同的参数下,利用镍基合金粉末分别在基板未预热和分别预热到300℃、400℃、500℃、600℃时进行了成形试验,试验的结果跟数值模拟结果吻合较好。

地幔对流理论及其在解释地球物理观测的应用

With the improving of mantle convection theory, the developing of computing method and increasing of the measurement data, we can numerically simulate more clearly about the effects on some geophysical observed phenomenons such as the global heat flow and global lithospheric stress field in the Earth's surface caused by mantle convection, which is the primary mechanism for the transport of heat from the Earth's deep interior to its surface and the underlying force mechanism of dynamics in the Earth.Chapter 1 reviews the historical background and present research state of mantle convection theory.In Chapter 2, the basic conception of thermal convection and the basic theory about mantle flow.The effects on generation and distribution of global lithospheric stres s field induced by mantle flow are the subject of Chapter 3. Mantle convection causes normal stress and tangential stresses at the bottom of the lithosphere, and then the sublithospheric stress field induces the lithospheric deformation as sixrface force and results in the stress field within the lithosphere. The simulation shows that the agreement between predictions and observations is good in most regions. Most of subduction zones and continental collisions are under compressive. While ocean ridges, such as the east Pacific ridge, the Atlantic ridge and the east African rift valley, are under tensile. And most of the hotspots preferentially occur in regions where calculated stress is tensile. The calculated directions of the most compressive principal horizontal stress are largely in accord with that of the observation except for some regions such as the NW-Pacifie subduction zone and Qinghai-Tibet Plateau, in which the directions of the most compressive principal horizontal stress are different. It shows that the mantel flow plays an important role in causing or affecting the large-scale stress field within the lithosphere.The global heat flow simulation based on a kinematic model of mantle convection is given in Chapter 4. Mantle convection velocities are calculated based on the internal loading theory at first, the velocity field is used as the input to solve the thermal problem. Results show that calculated depth derivatives of the near surface temperature are closely correlated to the observed surface heat flow pattern. Higher heat flow values around midocean ridge systems can be reproduced very well. The predicted average temperature as a function of function of depth reveals that there are two thermal boundary layers, one is close to the surface and another is close to the core-mantle boundary, the rest of the mantle is nearly isothermal. Although, in most of the mantle, advection dominates the heat transfer, the conductive heat transfer is still locally important in the boundary layers and plays an important role for the surface heat flow pattern. The existence of surface plates is responsible for the long wavelength surface heat flow pattern.In Chapter 5, the effects on present-day crustal movement in the China Mainland resulted from the mantle convection are introduced. Using a dynamic method, we present a quantitative model for the present-day crustal movement in China. We consider not only the effect of the India-Eurasia collision, the gravitational potential energy difference of the Tibet Plateau, but also the contribution of the shear traction on the bottom of the lithosphere induced by the global mantle convection. The comparison between our results and the velocity field obtained from the GPS observation shows that our model satisfactorily reproduces the general picture of crustal deformation in China. Numerical modeling results reveal that the stress field on the base of the lithosphere induced by the mantle flow is probably a considerable factor that causes the movement and deformation of the lithosphere in continental China with its eflfcet focuing on the Eastern China A numerical research on the small-scale convection with variable viscosity in the upper mantle is introduced in Chapter 6. Based on a two-dimensional model, small-scale convection in the mantle-lithosphere system with variable viscosity is researched by using of finite element method. Variation of viscosity in exponential form with temperature is considered in this paper The results show that if viscosity is strongly temperature-dependent, the upper part of the system does not take a share in the convection and a stagnant lid, which is identified as lithosphere, is formed on the top of system because of low temperature and high viscosity. The calculated surface heat flow, topography and gravity anomaly are associated well with the convection pattern, namely, the regions with high heat flow and uplift correspond to the upwelling flow, and vice versa.In Chapter 7, we give a brief of future research subject: The inversion of lateral density heterogeneity in the mantle by minimizing the viscous dissipation.

成年女儿照料老年父母的心理体验及关系质量作用的研究

Previous researches about family caregiving revealed that caregiving has both negative and positive effects on caregivers’ well-being. Based on Lawton’s two-factor model, this study aims at examining how caring for old parents would affect adult daughters’ psychological well-being. According to Lawton, objective stressors as caregiving would arouse two different kinds of caregivers’ subjective appraisal, i.e., negative appraisal and positive appraisal, which in turn correlate with the negative and positive dimensions of caregivers’ psychological well-being, respectively. There were two main purposes of this study: a) to verify both the negative and positive paths in the two-factor model and their relatively independence; and b) to examine the effects of relationship quality between caregiver and care-recipient on those paths. The results are as follows: 1) Caregiving stressors have significant positive predictive effect on caregivers’ negative appraisal, but have no direct effect on caregivers’ positive appraisal. 2) Caregivers’ negative appraisal has significant positive predictive effect on their negative emotional experience, while caregivers’ positive appraisal has significant positive predictive effect on their positive emotional experience. 3) Certain dimensions of relationship quality, including the Appreciation and General Appraisal, have significant negative predictive effect on caregivers’ negative appraisal, and have significant positive predictive effect on caregivers’ positive appraisal. 4) The Appreciation dimension of relationship quality moderates the path from caregiving demands to caregivers’ burden; and the General Appraisal of relationship quality moderates the path from caregivers’ positive appraisal to life satisfaction. Based on the above results, the researcher concluded that a) both the negative path and positive path exist in caregiving process, and they are relatively independent from each other; and b) relationship quality does moderate certain paths in the model. Meanwhile, the main effect of relationship quality on caregivers’ experience is also significant and more remarkable. This study attempts to explain these results in terms of coping resources. Both relationship quality and many other factors might be explained as resources that caregivers utilize to cope with stress of caregiving. With more resources, caregivers tend to appraise more positively, and less negatively, and vice versa. However, the resources which might affect caregivers’ positive appraisal, as well as the ways they work, may be different from that affect caregivers’ negative appraisal.