地下水渗流对基坑侧压力的影响

为研究地下水渗流对基坑侧压力的影响,针对经典算法结果偏差较大的现象,从理论上分析了地下水渗流对基坑主动区侧压力和被动区侧压力的影响机理,考虑了地下水的渗流作用,采用有效应力原理,提出了计算基坑支护结构侧压力的新方法。实例分析结果表明,新方法的计算结果与实测值相符,更能反应工程实际情况。     

时间序列分析方法在股票市场中的应用

近年来预测股市的未来变化是一个热门的研究课题.文章从技术分析的角度出发,利用股票市场的基础数据作为研究的对象,建立相应的时间序列模型,并与BP网络算法比较,结果表明该时间序列方法对股市短期预测精度较高.     

基于可靠性分析的胚胎硬件容错策略选择方法

胚胎硬件的容错策略是影响阵列可靠性的重要因素, 可靠性分析可从理论上得到理想的容错策略和阵列布局, 为硬件优化设计提供目标. 胚胎硬件可靠性分析的传统模型仅考虑阵列布局结构, 视细胞为固定节点, 不考虑容错电路设计中细胞内部电路模块的变化, 未能全面反映电路设计的实际情况. 针对这一不足, 提出了新的可靠性模型, 将细胞内配置存储器和输入输出布线器电路的变化 情况引入到建模过程中, 经过实例仿真分析, 总结出了基于可靠性分析的容错策略选择方法和分析步骤, 给出了可指导如何选择容错策略选择的量化条件.     

A TiCx reinforced Fe (Al) matrix composite using in-situ reaction

A new Fe matrix composite reinforced by the in-situ generated TiCx grains was prepared using the element Fe and Ti3AlC2 powders as the starting materials.Several hot-pressing temperatures were tried for exploring the phase transformation behavior from Ti3AlC2 to TiC x.Microstructures of the hot-pressed product were observed and analyzed.A tensile test was carried out for the new composite material,and the fracture face was analyzed.The results showed that the starting Ti3AlC2 was wholly decomposed and transformed into submicron TiC x grains at the hotpressing temperature above 1100℃.Most of the Al ions escaped from Ti3AlC2 were aggregated at the grain boundary of Fe grains,but a small amount of Al ions could be absorbed by Fe and formed Fe(Al) alloy around the surface of Fe grains.The prepared material exhibited a higher tensile strength of about 660 MPa and a uniform deformation of about 7%.     

基于自抗扰控制的秒流量AGC研究

在传统秒流量AGC控制器的基础上,针对其系统非线性、时变及干扰因素多的特点,提出一种基于改进自抗扰控制的秒流量AGC控制方法。根据某四辊板带冷轧机各部分工作原理及相应的参数建立被控对象模型,并对传统秒流量AGC系统和基于改进自抗扰控制的秒流量AGC系统分别进行仿真分析。结果表明,基于改进自抗扰控制的秒流量AGC系统具有更好的动态响应、鲁棒性和抗干扰能力。     

基于Matlab的小世界网络仿真

本文基于Matlab软件实现小世界网络模型算法,并利用Pajek软件做出小世界网络的图像,为培养学生的数学建模能力提供了一个较好的案例。     

葫芦科作物离体雌核发育的研究进展

对葫芦科作物离体雌核发育的研究进行了综述,包括离体雌核发育的研究现状、以及基因型、胚囊发育时期、培养基、预处理、培养方式等因素对离体雌核发育的影响,并对离体雌核研究的发育趋势进行了预测.     

水流绕过二维方形障碍物的湍流数值模拟

采用了混合有限分析求解方法对湍流绕过二维方形障碍物进行了数值模拟,模拟雷诺应力项时采用了布辛涅斯克假定.采用了k-ε双层模型进行计算,通过与文献中的实验结果及数值计算结果的比较验证了本计算方法的有效性.模拟结果表明k-ε双层模型较壁面函数法预测湍流绕过方形障碍物时更为准确;障碍物高度及流动条件不变时(Re=1.4×104,H=1.0),随着方形障碍物长度的变化,障碍物上游的旋涡Ⅰ的长度基本上没有变化,而在障碍物的下游当L/H≥4时旋涡Ⅱ的长度也基本上保持不变.     

Research on characters of surrounding rock in complex geology conditions and supporting time

The methods combined by test, field monitoring and theoretical analysis were adopted to do the systemic research on the rock mass from micro-structure to macro-deformation, and rheological model of Jinchuan rock mass was established to discuss the reasonable supporting time. Resuhs show that supporting after suitable stress and displacement release can benefit for the long-term stability of surrounding rock.     

Dynamics of a qubit—TLS system under resonant microwave driving

We demonstrate the effect of different coupling strengths between a microscopic two-level system(TLS)and a microwave field on the dynamics of a qubit—TLS system when the bipartite system is subject to resonant microwave driving.Rabi beating with a different TLSmicrowave coupling strength is demonstrated in simulations.Entanglement,quantified by the concurrence between the qubit and TLS,both for pure states and mixed states,is simulated.When decoherence is considered,entanglement of the bipartite system oscillates with damping and exhibits entanglement sudden death and/or entanglement sudden death and revival.