汽车半主动悬架系统的高精度模糊控制

对于时变非线性的汽车半主动悬架系统,本文选用二元双线性插值模糊控制算法,在未经优化的控制规则作用下,进行仿真实验,表现出响应快、舒适性、平顺性与安全性兼具的特点,得到了与相关文献相近或更好的控制效果.     

端午节的历史传承与当代复兴

端午节在战国时代初步形成,源于古人虔诚的原始信仰。原始信仰是当时节俗传承的足够动力。魏晋时期原始信仰比以前淡化了,端午节传承的原初动力也消弱了,这时人们加入了纪念屈原等历史人物传说来解释端午习俗,为端午节增加了新的文化内涵和习俗。但是由于端午节习俗不重视家庭团聚和祭祀祖先,在契合儒家文化方面不很显著,因而在魏晋以后的儒教时代出现了传承动力不足的问题。到现代社会,端午习俗面临传承危机。但经研究可见到,端午习俗包含着适合现代文化的丰富要素,可以进行适应现代社会的调适、更新。在重视非物质文化遗产保护的社会背景下,它更有了复兴的契机和动力。     

推广的双向积分不等式及其应用

对一类开型的最佳两点积分法则:ba∫f(t)dt=b-a2[f(3a+b4)+f(a+3b4)]+R(f),通过构造函数p1(t),p3(t),导出了两点积分法则上下误差界的双向积分不等式,并得到了相应的最佳上下误差界;另外,考虑到两点积分法则的一个扰动,这个扰动后的法则优越于原始的积分法则;最后,给出了这些结果在数值积分中的应用。     

双J管在ESWL中的应用及护理

目的探讨双J管在ESWL中的临床效果及护理措施.方法将400例肾、输尿管结石(结石大小1.5～3.5cm)病人随机分为治疗组200例,在体外冲击碎石(ESWL)前经膀胱镜插入双J管;对照组200例不插入双J管,所有病人均行ESWL治疗.结果治疗组病人有12例(6%)发生石巷,对照组26例(13%)发生石巷两组治疗后比较则显著率及(P<0.05).结论在ESWL前放置双J管,配合护理人员密切观察病情,精心护理,可明显降低石巷的发生率,减少碎石并发症.     

Mechanism of surface texture evolution in pure copper strips subjected to double rolling

Developing ultra-thin copper foils with different surface roughness and microstructure has important significance for improving the service performance and reducing the production cost of high-end circuit boards. In this paper,pure copper strips with initial cube texture were subjected to a double rolling process(deformation amount ranges from 50% to 95%),and the surface textures evolution law and mechanism of doublerolled strips were studied by an X-ray diffraction technique. The results show that when a deformation amount increased from 50% to 70%,the grains of two surfaces rotate away from the cube orientation,and the formed textures of two surfaces mainly consisted of C,S and B orientation components. The orientation density values for these three components on bright surface only had slight difference; the orientation density values for C and S components were much larger than that for B components on a matt surface. When the deformation amount increased to 90%,the increase extents of orientation density values for C and S components were obviously larger than that for B components on a bright surface; the increase extents of orientation density values for these three components were almost the same on the matt surface. It has been found that when deformation amount reaches 95%,the grains orientation of bright surface were relatively concentrated,and the orientation density value for C texture obviously increased to 11.68 and that for B texture was only 3.15; the grains orientation of matt surface were relatively dispersed,and the orientation density value for C texture increased to 9.26 and that for B texture obviously increased to 6.35,and the density values of these two textures had less difference. For the condition of strong compressive and shear stress on the bright surface,grains were mainly rotating to C texture orientation; compared with the bright surface,"semi-free" deformation condition on the matt surface is beneficial to promote much more grains to rotate to the B texture orientation.     

大学物理实验分层次教学模式的构建

培养学生的基本实验素质是大学物理实验教学的主要目标之一,本文对如何利用基础性物理实验所具有实验难度低、实验时效高的特点,通过设计合理的教学模式,达到培养学生的动手能力和激发学生的创新意识的教学目标进行了探讨。     

数字PD-PID控制的打号机随动系统

介绍了碳素行业电极打号机电气传动装置随动系统的组成,分析了采用数字双模(PD-PID)控制器的工作原理并给出了程序框图.通过1 a多的运行实践证明,本系统具有稳态精度高、定位准确、无振荡、快速性好等静、动态优良控制性能.     

通过双循环矩阵改进的基于纠错码的身份认证方案

目前所有的公钥密码方案都基于大整数分解或离散对数难题,这些困难问题在量子计算机中都可以在多项式时间内求解,因此所有的公钥方案都将面临危险,而基于纠错码的密码方案可以抵抗量子计算机的攻击,所以很有必要研究基于纠错码的身份认证方案。Stern身份认证方案总体来说很不错,但其公钥太大,达到150 Kbit;Veron提出一种改进的方案,目的也在于减少Stern方案中的公钥,在Veron方案中,Veron用生成矩阵来替代校验矩阵,使得所构造的公钥大大减小,但是其基于的安全性GSD问题没有得到很好地证明。现采用双循环矩阵来解决Stern方案中的密钥太大的问题,就是通过双循环矩阵把私钥嵌入到公钥中。这样做的好处有两点:1所基于的安全性是已被证明为安全的循环码;2改进以后,公钥只有347bit,而私钥大小也只有694 bit。并且分析所构造方案的安全性,将其归结到双循环线性条件下的SD问题。因为使用循环结构,使得实现起来比较容易并且效率很高。这些特点使得方案在轻量级结构的场合具有广阔的应用前景,比如手持终端,云存储环境下的数字签名等场合。     

基于单片机的数控恒流源设计

介绍一种针对工企业应用中电磁阀门开启度大小,而设计的具有手动与自动两种控制方式的,内嵌式数控恒流源电路.     

跟踪式尖顶型聚光光伏发电的研究

采取主动和被动相结合的方式分别控制方位角和仰角的自动跟踪,结合不需解决散热问题的尖顶型聚光方式,设计制造低成本和高可靠性的跟踪式尖顶型聚光光伏发电装置,使光伏发电量理论上增加1．9倍,较大地降低光伏发电成本,是实用的能够产业化推广的跟踪式聚光光伏发电技术．同时,通过分析实测发电数据,得出跟踪式聚光发电更适合建在直射光成分含量较多的地方．