上海股市收益与流动性风险动态关系实证

应用Engle(2002)提出的动态条件相关多元GARCH模型(DCC-MVGARCH)和向量自回归(VAR)方法,研究了上海股票市场收益与Acharya and Pedersen(2005)提出的三种流动性风险以及系统风险变量的动态关系.研究结果表明,上海股市存在系统风险溢价和流动性风险溢价,但风险变量对收益率的影响较小,股市的风险传递机制尚未真正形成.     

软质电容式车辆动态称重系统

介绍了一种软质电容式车辆动态称重系统.对该传感器静态特性进行了研究,分析了受力面积和时间的影响,针对橡胶材料粘弹性特性,提出了利用四元件模型对其建模.同时进行了动态实验,车辆总重量的测量误差在10%以内,其精度优于ASTME1318-02给出的Ⅰ类WIM系统精度(置信95%时总重误差±10%).实验结果表明:利用文中提出的车辆动态称重系统进行测量是可行的,它有助于随时测量,便于交通稽查.     

BiMnO3的铁电铁磁机制,轨道有序和自旋有序的第一原理

为了探讨多铁材料铁电畸变的根本机制及其电子结构对于性能的影响,采用基于密度泛函理论的广义梯度近似方法,对多铁材料BiMnO3的高温顺电顺磁相、室温铁电顺磁相和低温铁电铁磁相的电子结构做了第一原理计算.对态密度、电子密度以及Mulliken电荷等计算结果的分析表明:Bi-6p轨道与O-2p轨道间的选择性共价作用增强是铁电畸变的首要引发因素,6s电子的极化也是其导致的效应之一.对与多铁现象共生的轨道有序和自旋有序的研究指出了去中心化的晶格畸变、Jahn-Teller畸变和自旋失措引发的晶格畸变三者之间的相互耦合以及耦合对铁电铁磁性的影响.     

基于信任区技术的可信移动电子政务系统设计

通过移动电子政务,用户可以在任何地方、任何时间进行远程办公,给用户提供了方便和快捷的办公方式,移动电子政务的安全性主要体现在终端的安全性。目前手机安全措施还不是很完善,针对存在的安全问题,通过对现有手机硬件架构的改进,使用信任区技术和可信计算技术实现可信移动电子政务系统,保证了用户办公的安全性。     

缩放管内CaCO_3污垢形成过程的数值模拟

利用从传热传质角度结合表面化学反应知识模拟CaCO3污垢形成过程的数学模型,对缩放管不同工况进行了数值模拟计算.得出不同工况下,缩放管内CaCO3污垢的沉积率、剥蚀率、污垢热阻随时间的变化规律以及它们与流速、工质浓度、温差的关系.     

利用玉米秸秆制备高吸水树脂

将玉米秸秆预处理后与丙烯酸接枝共聚制备高吸水性树脂,采用单因素实验确定了合成条件中各因素的最佳水平:θ=45℃,引发剂中过硫酸钾用量为单体质量的0.8%,交联剂N,N-亚甲基双丙烯酰胺(MBAM)用量为单体质量的0.6%,m(AA)∶m(玉米秸秆)=8∶1,丙烯酸中和度为70%,t=4 h。对最佳条件下制备的树脂进行了性能测试,对秸秆预处理前后及产物进行了扫描电镜分析。结果表明,该树脂具有良好的吸水、保水性能,吸水率最高达到291 g.g-1,吸盐水率达到49 g.g-1。     

中西体育文化比较研究

在对中西体育文化渊源进行比较分析的基础上,阐述了中西体育文化观念上的差异,并提出了中西合璧,构建现代奥运精神的设想。     

Evaluation of group effect of pile group under dragload embedded in clay

A simple semi-empirical analysis method for predicting the group effect of pile group under dragload embedded in clay was described assuming an effective influence area around various locations of pile group. Various pile and soil parameters such as the array of pile group, spacing of the piles (S), embedment length to diameter ratio of piles (L/D) and the soil properties such as density (γ), angle of internal friction (φ) and pile-soil interface friction coefficient (μ) were considered in the analysis. Model test for dragload of pile group on viscosity soil layer under surface load consolidation conditions was studied. The variations of dragload of pile, resistance of pile tip and the layered settlement of soil with consolidation time were measured. In order to perform comparative analysis, single pile was tested in the same conditions. The predicted group effect values of pile group under dragload were then compared with model test results carried out as a part of the present investigation and also with the values reported in literatures. The predicted values were found to be in good agreement with the measured values, validating the developed analysis method. The model test results show that negative skin friction of pile shaft will reach 80%–90% of its maximum value, when pile-soil relative displacement reaches 2 mm. Foundation item: Project(50679015) supported by the National Natural Science Foundation of China     

江西省农业旱情预测模型的建立与应用

根据农业用地的不同性质分别建立旱地缺墒模型,灌溉水田、水浇地、菜地与望天田缺水度模型,并据此建立江西省农业旱情预测模型,对江西省农业旱情进行预测.为科学抗旱和减少旱灾损失提供依据和指导.     

Relationship of hydrocarbon and source-rock in Nos.3-5 tectonic belts of the Lenghu area, northern Qaidam Basin

Based on analyses of the components of crude oil hydrocarbons and carbon isotopes, the content of normal alkane de-creased from 49.00% to 20.10% when moving from the No.3 to No.5 tectonic belt of the Lenghu area of the Qaidam Basin, while cycloalkanes increased from 30.00% to 52.20% and aromatic and branch chain alkanes increased gradually as well. The maturity of sterane in crude oil is higher than that of its source-rock, which shows that the hydrocarbons were generated from a deep source-rock of high maturity around the tectonic belts of the Lenghu area. The analysis of the characteristics of carbon isotopes also shows that these isotopes of hydrocarbon compounds in the No.4 and No.5 tectonic belt are apparently heavier than those in the No.3 belt. The results of our research show that the hydrocarbons in the No.3 tectonic belt are mainly from a relatively rich sapropelic substance, while the hydrocarbons in the No.4 and No.5 tectonic belt originated mainly from organic matter of a rela-tively rich humic type substance.