移动终端动态加载机制研究

随着移动终端系统深入发展,应用程序扩展能力已成为一个基本需求,中低端移动终端系统迫切需要一种机制能使系统在运行状态时动态添加模块。该文提出一种内存分配策略及基于虚拟函数表结构动态加载机制,给出了应用程序加载实现方法。实验结果表明:基于该机制所开发的加载器具有体积小,运行速度快,性能稳定等特点。     

混合装配线过程平衡研究与仿真

生产过程的混合装配线平衡问题,分为在确定条件下的最小生产循环单元的静态平衡问题和不确定条件修正过后的动平衡问题.针对确定工位条件下的混装生产线,构建其静态平衡模型,分析不确定因素,并以操作工人的操作时间不确定性为例,研究时间不确定性动态平衡.利用Flexsim软件,通过仿真进行了验证.相关实验验证了上述方法和结论的正确性.     

时延动态神经网络的稳定性分析

基于时延动态网络模型的优化计算易于收敛到非法解或局部极小解,以及其算法对模型参数和初始条件具有很强的依赖性等缺点,对时延动态神经网络的稳定性进行了深入地研究讨论,通过Razumikhin-type定理对时延动态神经网络的稳定性进行了分析研究.     

竖向恒载对框架结构动力稳定性影响研究

以框架结构为例,建立了结构动力稳定性分析的基本模型,提出了利用动力响应的敛散性来判断结构动力稳定性的具体方法.通过算例分析,给定不同的竖向恒载值,得到框架结构在水平动力荷载作用下的临界荷载值,结果表明,竖向恒载对动力稳定性有明显影响,但动力临界荷载与相应静力临界荷载的比值变化不大.     

Hot-compression behavior of Al-1Mn-1Mg alloy

The hot-compression of Al-1Mn-1Mg (mass fraction, %) alloy sample was carried out on a Gleeble-1500 thermo-simulator at deformation temperatures from 320 to 400 ℃ and strain rates from 0.1 to 10 s-1 by total strain of 1.4. Microstructure and texture evolution of the hot-compressed alloy were investigated by optical microscopy and X-ray diffraction analysis, respectively. The results show that the relationship among flow stress σ, deformation temperature T and strain rate ε can be expressed in the form of βσ...     

M-distinct算法改进：面向动态数据集重发布的隐私保护算法

M-distinct extension算法通过将数据添加、删除、更新三种情况分开处理,在删除情况下引入伪记录的概念,使得攻击者无法得出插入和删除数据之间的联系;另一方面提出事实：数据记录的不同属性在不同的发布用途中其信息权重并不相同,根据事实,引入属性权重的概念,减少算法在分配和划分两个阶段的循环次数,提高算法的效率。     

Dynamic surface control-backstepping based impedance control for 5-DOF flexible joint robots

A new impedance controller based on the dynamic surface control-backstepping technique to actualize the anticipant dynamic relationship between the motion of end-effector and the external torques was presented. Comparing with the traditional backstepping method that has “explosion of terms” problem, the new proposed control system is a combination of the dynamic surface control technique and the backstepping. The dynamic surface control (DSC) technique can resolve the “explosion of terms” problem that is caused by differential coefficient calculation in the model, and the problem can bring a complexity that will cause the backstepping method hardly to be applied to the practical application, especially to the multi-joint robot. Finally, the validity of the method was proved in the laboratory environment that was set up on the 5-DOF (degree of freedom) flexible joint robot. Tracking errors of DSC-backstepping impedance control that were 2.0 and 1.5 mm are better than those of backstepping impedance control which were 3.5 and 2.5 mm in directions X, Y in free space, respectively. And the anticipant Cartesian impedance behavior and compliant behavior were achieved successfully as depicted theoretically.     

高岭土/聚甲基丙烯酸甲酯核壳结构复合粒子对聚丙烯动态机械性能的影响

采用乳液聚合方法,以高岭土为核,甲基丙烯酸甲酯(MMA)为壳制备了具有核壳结构的共聚物。将制得共聚物与聚丙烯共混,用动态机械分析仪测试其共混物的动态机械性能,得出共混体系中温度与内耗因子的关系,温度与储能模量的关系以及温度与损耗模量的关系,并对所得的参数进行对比分析。研究表明,该种核壳结构的共聚物粒子与聚丙烯有很好的相容性,可以提高聚丙烯材料的阻尼性能,且可降低聚丙烯材料的玻璃化温度从而改善聚丙烯的柔韧性。     

供热网循环水泵效率的研究

城市供热系统是极其重要而复杂的大系统,为了提高系统的社会效益和经济效益,从大连北海热电集团热电联产供热管网的实际出发,运用了最小二乘法原理,对采暖循环水泵的性能数据进行曲线拟合,得出了水泵的真正运行状况,并且对使用单台水泵、双台并联或3台并联水泵3种不同情况下的水力工况水泵效率进行了比较和分析。结果表明,单纯地增加并列泵数量对增加流量并无显著变化,并且使并列泵的效率明显下降,只有认真进行严格地工况分析,找到最佳工况点,才能保证整个热系统正常运行。     

Deformation behavior and microstructure of an Al-Zn-Mg-Cu-Zr alloy during hot deformation

The hot deformation behavior and microstructures of Al-7055 commercial alloy were investigated by axisymmetric hot compression at temperatures ranging from 300°C to 450°C and strain rates from 10-2 to 10 s-1,respectively.Microstructures of deformed 7055 alloy were investigated by transmission electron microscopy (TEM).The dependence of peak stress on deformation temperature and strain rate can be expressed by the hyperbolic-sine type equation.The hot deformation activation energy of the alloy is 146 kJ/mol....