Web报表打印技术研究

针对基于B/S结构的Web报表难以打印输出的问题,提供了一种简单实用的基于B/S结构的Web报表打印技术。该研究通过将微软的ASP技术和IE内置的浏览器控件WebBrowser进行结合生成,注重简单、容易使用。通过研究得了一种较为完善的可以完全定制的Web报表技术,代码简练、实用,特别适用于具备微软ASP的技术人员使用。     

基于LQR的粘弹性阻尼器参数优化方法

粘弹性阻尼器(VED)参数优化是VED设计中的一个重要问题。通常采用LQG最优控制进行参数优化,该方法需建立滤波器,将有色噪声转化为白噪声,需求结构的响应方差,比较复杂。采用等效刚度和等效阻尼力学模型,基于LQR控制优化理论提出了VED参数优化方法,将被动控制效果与主动控制效果逼近,通过矩阵初等变换,根据最小二乘法推导了VED的参数优化公式。计算实例表明所提出的方法是非常有效的。     

考虑饱和永磁伺服系统速度调节的设计与调整

针对经典控制理论设计的速度调节器与实际调试结果出入大，以及在速度阶跃过程中速度调节器的饱和问题，提出用线性二次型状态反馈的设计思想，实现伺服系统速度调节器的设计。在速度调节器饱和过程中，采用棒棒控制实现响应时间的最小化。为保证动态过程中系统速度调节器的平稳过渡，合理选择调节器的转换阀值，并引入速度微分反馈控制，可以在不影响系统响应快速性的前提下抑制超调与振荡。在电机速度阶跃过程中，加大系统动态过程中的限幅力矩，使系统的响应更快，响应时间更短。数字仿真和实验均证实了文中所做分析与设计的有效性。     

关于Jensen不等式的应用

利用凸函数的Jensen不等式为基础，证明其他的几个重要的不等式。     

Smith图合成规范化关系模式的法则与证明

本文介绍了基于Ｓｍｉｔｈ图的计算机辅助数据库设计的基础理论和由Ｓｍｉｔｈ图合成规范化关系模式的合成法则，给出了一个定理并证明了由合成法则得到的关系模式是完全规范化的。     

二次曲面的切平面

本文探讨了在没有给出椭球面、双叶双曲面,椭圆抛物面图形的条件下,过曲面外一给定直线作该曲面切平面和作与该曲面相切且与给定平面平行的切平面的问题。     

EMS报表系统中增加电网负荷考核功能的实施方案

为了加强对并网电厂的负荷及上网电量的考核,解决青海电网的考核统计问题,在EMS报表系统中增加电网负荷考核功能是解决问题的方法之一。文章指出了利用现有的电网调度自动化系统及报表管理系统进行电网负荷考核所在的问题及改进的必要性,介绍了方案的具体实施及实施后收到良好的效果,为电网的安全运行,并网电厂的调度管理提供了技术支持。     

Simulation of a DC Discharge in a Transverse Supersonic Gas Flow

This study is devoted to the investigation of a dc discharge in a transverse gas flow. It is shown that the discharge may exist in several forms depending on the gas flow velocity. The standard stationary discharge similar to a discharge in still gas is realized if the displacement rate of the plasma boundary exceeds the gas flow velocity. The displacement rate of the plasma boundary in a diffusion model is defined by the relation V _f = 2 , where D _a is the ambipolar diffusion coefficient, and _i is the frontal ionization frequency. Otherwise, the discharge assumes the form of two plasma wakes formed by the cathode and anode, respectively. The surface of the plasma wakes is oriented at an angle to the flow velocity C _s (sin = V _f /C _s ). If sin is smaller than the ratio of the discharge sustaining voltage in the stationary regime U _st to the breakdown voltage U _bk , the discharge transforms into the pulse–periodic form, when the formation of a structure of the cathode and anode plasma wakes is interrupted by a new gas breakdown. A numerical simulation of the discharge properties is performed. The numerical simulation results are compared to the experimental ones.     

The macromolecular polymers for the preparation of hydrodynamically balanced systems--methods of evaluation

Evaluation of macromolecular polymers used as excipients for the preparation of hydrodynamically balanced systems (HBS) was carried out. Hard gelatine capsules were filled with polymeric substances belonging to various chemical groups (chitosan, sodium alginate, hydroxypropylmethycellulose—HPMC). The following properties of the HBS were investigated: density, hydration, erosion and floating force. The solvent penetration process into the HBS was visualized using magnetic resonance imaging (MRI) technique. Densities of the HBS in hydrochloric acid (0.1 M) ranged from 0.37 g/cm³ to 0.71 g/cm³. Each polymer demonstrated different hydration/erosion abilities and floating properties. The maximum floating force (F_{float max}) for capsules size 0, ranged from 26.7 mN (sodium alginate) to 64.7 mN (chitosan). HBS formulations also varied in time to reach maximum floating force (T_{float max}). HPMC and sodium alginate formulation reached F_{float max} within half an hour after immersion, while in the case of chitosan formulations (deacetylation degree (d.d.) 66% and d.d. 93%), the time was 184 minutes and 218 minutes respectively. The floating properties of the dosage forms were reliant on type of the polymer and the medium—fasted state simulated gastric fluid (FaSSGF) or fed state simulated gastric fluid (FeSSGF). The size of the HBS influenced the floating force value. The mechanisms of erosion and swelling of the polymeric matrices play a dominant role in flotation of the dosage forms.