CAN时分信息和优先级晋升实时调度策略

基于事件触发和静态优先级的CAN网络在网络负载较大时,通信的实时性难以保证.为此研究了时分信息和优先级晋升信息实时调度策略,并给出了相关策略在应用中的改进和算法实现.     

工业控制系统中可靠性设计的研究

本文主要阐述了在工业生产控制系统中,可靠性设计中的热设计、电磁防护设计、机械防震设计,提出了可靠性设计中应当注意的问题,以及一些解决问题的方案和办法.热设计中应当主要注意温度,电磁防护设计中应当主要注意屏蔽和接地,机械防震设计中应当主要注意防震.     

利用仿真软件优化电磁场与电磁波教学

针对电磁场与电磁波课程理论公式复杂、相关概念模型抽象的特点,结合长期积累的教学经验,利用软件仿真将电磁场定理模型、分布特性可视化,简化推导计算过程,优化课程结构、节省课时的同时提高了教学效果。     

悬浮液进样-火焰原子吸收光谱法测定茶叶中的微量铬

将茶叶悬浮于琼脂胶体中制成悬浮液 ,直接喷入空气 -乙炔火焰 ,用火焰原子吸收光谱法测定茶叶中的微量铬 ,方法简便、快速、灵敏度和精密度高、测定结果与用灰化法处理样品一致 ,检验表明 ,两种样品前处理方法之间无显著性差异。相对标准偏差为 3.4 %～ 6 .1% ,加标回收率为 95 .7%～ 10 3.8 %。     

非炭黑橡胶补强填料的应用研究进展

介绍非炭黑橡胶补强填料白炭黑、粘土、碳酸钙和短纤维的应用研究进展。白炭黑以其优良的补强性能成为最主要的白色、透明补强填充剂。白炭黑与硅烷偶联剂并用于轮胎胎面胶中，在降低轮胎滚动阻力的同时可改善轮胎的耐磨性和抗湿滑性。粘土／橡胶纳米复合材料具有良好的加工性能、优异的物理性能及阻隔性能等，广泛用于轮胎内胎、气密层、胶带、胶鞋等制品。碳酸钙尤其是超细活性碳酸钙已成为性能较好、白度高的橡胶补强填充剂之一，随着橡胶制品向品种齐全、用途广泛和色彩丰富方向发展，其应用将更加广泛。短纤维补强橡胶复合材料既具有橡胶的弹性，又有纤维的强度和刚度，制品具有高强度、高模量、耐撕裂、抗溶胀等优良性能，其复合材料已用于轮胎胎圈包布胶、三角胶、内衬层和胎面及胶管和输送带等产品。     

Deformation and failure study of surrounding rocks of dynamic pressure roadways in deep mines

In order to understand the change rules of stress-displacement in surrounding rocks of dynamic pressure roadways in deep mines and to obtain a theoretical basis for analyses of roadway stability and designs of support,we established a coupling equation of adjacent rock strength,mining stress and supporting resistance on the basis of an elastic-plastic theory of mechanics.We obtained an analytical solution for stress and displacement distribution of elastic and plastic regions in surrounding rock of dynamic pressure roadway..Based on this theory,we have analyzed the changes in stress-displacement in elastic and plastic regions of surrounding rocks of dynamic pressure roadways in the Haizi Coal Mine.The results show that:1) radial and tangential stress change violently within the first 4 m from the inner surface of a roadway after excavation;radial stress increases while tangential stress decreases within a range of about 6 m from the inner surface of the roadway as a function of q3;2) radial and tangential stress increase with an increase in the mining pressure coefficient k;the increase in the rate of tangential stress is greater than that of radial stress;3) the radial displacement of the inner surface of roadways decreases with an increase in q3,provided that k remains unchanged.     

电磁领域中复超越方程的遗传算法求解方法

将遗传算法与参数跟踪策略有效结合,跟踪过程中进行搜索域压缩与位移操作,形成了一种功能强大的新算法,可成功应用于电磁领域中各种各样复超越方程的高精度求解问题.在算法实现过程中,使用参数跟踪策略有效地缩小了搜索区域,保证了解的单一性,提高了运算速度;使用动态搜索域提高了解的精度;应用三阶差商公式预估新的搜索中心,使运算速度得以进一步提高.应用本文发展的算法详细求解了终端短路法测量材料的复介电常数时得到的复超越方程和部分填充矩形波导的特征方程,计算结果表明该算法能够轻松地解决复超越方程中的多值问题,解集完备性好,算法鲁棒性强.     

Electroless nickel plating on the surface of carbon fibers

The electroless nickel plating on the surface of carbon fibers was prepared by pretreating the carbon fibers in order to increase their conductivity,and consequently enhance the EMI shielding effectiveness of the composites.The relationship between the performance of depositing coat and pH value,temperature,reaction time and the way of agitation was studied.Results show that the depositing quality is stable under pH between 4.5 and 5.0,temperature between 75 ℃ and 85 ℃,reaction time for 10 min and air agitation.The uniform and compact nickel layer deposited on carbon fibers was proved by XRD and SEM,and the electrical resistivity of carbon fibers with nickel coating was tested.Results indicate that the electrical resistivity of carbon fibers with electroless nickel plating is decreased by an order of magnitude compared with that of carbon fibers.It means that nickel coating can greatly improve the electromagnetic interference shielding properties of carbon fibers.     

基于自学习规则和改进贝叶斯结合的问题分类*

根据对中文问题的分析可知,问题中的疑问词和中心词等关键词对问题所属类型起着决定性的作用。提出利用自学习方法建立疑问词—类别和疑问词+中心词—类别两种规则,并结合改进贝叶斯模型的问题分类方法。该方法充分利用了关键词对分类的贡献。实验结果表明,该分类方法有很大的改进,准确率达到了84%。     

一种故障管理系统的层次化结构设计*

基于故障管理基本原理,提出了一种故障管理系统的层次化结构设计方案,分析了该层次化结构的基本特征,并研究了该结构在高端服务器上的实现技术。实际应用表明,该结构具有可行性,基于该结构实现的故障管理系统可较好地提高服务器可靠性。