电导法测定乙酸解离常数实验数据处理软件设计

介绍了用电导法测定乙酸解离常数的实验原理和步骤,给出了用计算机对电导法测定乙酸解离常数的实验数据进行处理的软件设计方法,同时给出了用Visual FoxPro 6.0编写电导法测定乙酸解离常数的处理软件的基本结构和部分程序代码。     

边界对齐的平滑三维对称标架场

为了把广泛应用于网格四边形化和纹理合成的二维表面标架场拓展到三维,提出一种生成三维对称标架场的方法.不同于表面对称标架场(四对称方向场),二维标架场的对称性能用一个切平面的旋转角度来表示,而三维对称标架场的对称性却不能这样简单地表示.为了解决这个问题,利用球面函数来获得一个对称性表述,该表述对于绕任意一个轴的π/2旋转以及它们的复合是不变的.基于球面函数的表示可以获得一个有效的标架场光顺程度的度量,并以球面调和分析进行加速计算;基于一组边界约束,可以通过极小化这个度量函数来获得一个光顺的标架场,该标架场在表面上能很好地对齐法线.最后通过表面投影、流线追踪和奇异点来可视化这个标架场,并将这个光顺的标架场用于六面体网格生成,且讨论了它在生成高质量纯六面体网格方面的潜力,其与表面标架场在生成四边形网格方面的潜力是一致的.     

解剖学的数字化实验教学平台的构建探索

随着数字医学及数字医疗技术的迅速发展,针对高等医学院校解剖实验教学中存在的问题,如何提高解剖学教学质量,文章介绍了数字化解剖,并分析了数字化解剖实验室的特点,将云计算技术应用到管理数字化实验教学中。给出了基于云计算技术的数字化解剖实验教学平台解决方案,改革数字化解剖实验室,提出一种新的数字化解剖教学模式。     

抛光液温控装置结构设计及温度场分析

为精确控制超光滑表面抛光过程中抛光液的温度,根据温控基本原理设计温控装置结构.将用UG建立的温控装置模型导入GAMBIT中进行温度场分析.针对装置内部温度分布不均匀问题,对其结构进行优化：在装置内加入导热隔板将其分为工作区和调温区,制冷器被置于调温区内;将温控装置的外形结构加入过渡圆角.结果表明：优化后的温控装置形成内外环流,工作区温度波动范围为±0.01℃,温度分布均匀对称,满足高精度温控的恒温和匀温要求.     

中职学校的计算机上机实验课

通过分析当今社会对中职学校学生的要求和目前中职学校计算机上机实验课中存在的问题,探讨了如何提高中职学校的计算机上机实验课程的教学水平。并根据当前中职学生的状况和特点,结合平时的教学经验,提出一些教学观念。     

一种基于多项式的代理保护代理签名体制研究

文章首先分析了张青坡等人中提出的多项式形式的E1Gamal签名体制的安全缺陷,然后基于有限域上多项式的性质,提出了有限域上多项式形式代理保护代理签名方案;新的签名方案中,利用多项式进行签名权利的委托,并由改进的有限域上的多项式形式的E1Gamal签名体制生成代理签名。新方案的安全性基于离散对数的难解性。     

Intelligent control of doubly‐fed induction generator systems using PIDNNs

An intelligent control for a stand‐alone doubly‐fed induction generator (DFIG) system using a proportional‐integral‐derivative neural network (PIDNN) is proposed in this study. This system can be applied as a stand‐alone power supply system or as the emergency power system when the electricity grid fails for all sub‐synchronous, synchronous, and super‐synchronous conditions. The rotor side converter is controlled using field‐oriented control to produce 3‐phase stator voltages with constant magnitude and frequency at different rotor speeds. Moreover, the grid side converter, which is also controlled using field‐oriented control, is primarily implemented to maintain the magnitude of the DC‐link voltage. Furthermore, the intelligent PIDNN controller is proposed for both the rotor and grid side converters to improve the transient and steady‐state responses of the DFIG system for different operating conditions. Both the network structure and online learning algorithm are introduced in detail. Finally, the feasibility of the proposed control scheme is verified through experimentation. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

CLP(ℜ) and some electrical engineering problems

The Constraint Logic Programming Scheme defines a class of languages designed for programming with constraints using a logic programming approach. These languages are soundly based on a unified framework of formal semantics. In particular, as an instance of this scheme with real arithmetic constraints, the CLP() language facilitates and encourages a concise and declarative style of programming for problems involving a mix of numeric and non-numeric computation.In this paper we illustrate the practical applicability of CLP() with examples of programs to solve electrical engineering problems. This field is particularly rich in problems that are complex and largely numeric, enabling us to demonstrate a number of the unique features of CLP(). A detailed look at some of the more important programming techniques highlights the ability of CLP() to support well-known, powerful techniques from constraint programming. Our thesis is that CLP() is an embodiment of these techniques in a language that is more general, elegant and versatile than the earlier languages, and yet is practical.An earlier version of this paper appeared in the proceedings of the 4th International Conference on Logic Programming, Melbourne, May 1987. Much of this work was carried out while the authors were at Monash University, Melbourne, Australia.     

偏最小二乘回归在气温预测中的研究与应用

气温的预测要考虑多重气象因子,然而各气象因子间的多重相关性导致普通的多元回归模型失真,预测精度降低。为了解决以上问题,本研究采用偏最小二乘回归(Partial Least Squares Regression,简称PLS)建模,根据实际建模需要对算法进行改进。为了验证该模型,本研究以成都市10月份气温场为预报场,并结合成都市13个自动站气温数据,提取预报所需主要因子,进行PLS回归建模。实验表明该模型有较好的预测能力。