牛顿环实验装置螺钉压力大小对曲率半径测量结果的探讨

研究牛顿环实验装置螺钉压力大小对平凸透镜曲率半径测量结果的影响。实验结果表明:在牛顿环的实验过程中,应把螺丝调整到合适的程度,使中心暗环直径在1~2 mm为宜。螺丝太松则导致平凸透镜和平板玻璃的触点不稳定,干涉条纹易受环境影响,使偶然误差增大。螺丝太紧则导致平凸透镜和平板玻璃之间弹力加大,使平凸透镜形变增大,导致中心斑增大,使测量系统误差增大。     

牛顿环现象及其应用

阐述了牛顿环干涉原理，解释了牛顿环实验图样和附加光程差对牛顿环图样的影响，并指出应用牛顿环现象可判断透镜表面凸凹、精确检验光学元件表面质量、测量透镜表面曲率半径和液体折射率。     

新型钢领钢丝圈系统

综述了几种新型的钢领钢丝圈系统，提出了将纳米和磁悬浮等高新技术应用于纺织器材的方法，并指出开发新型钢领结构是钢领钢丝圈系统的发展趋势。     

On algorithmically checking whether a Hilbert series comes from a complete intersection

It is not possible to determine from the Hilbert series whether a commutative -graded Noetherian algebra is a complete intersection. Nevertheless, the Hilbert series of a complete intersection satisfies very stringent conditions and we define a concept CI-type for formal power series, that embodies some of these necessary properties. This definition becomes interesting mainly for algebras that are not standard i.e. not generated in degree 1. For the class of formal power series that occur as the Hilbert series of -graded Noetherian Cohen–Macaulay algebras, the main result is a criterion for a series to be of CI-type, that is formulated in terms of properties of truncated power series. Hence it can be used as the basis for an algorithm that provides in a finite number of steps either a rational function expression of the formal power series, or the information that the truncated power series is not of CI-type. Also sample computations using this algorithm on some non-standard graded invariant algebras are described.     

环Fq+uFq++uk-1Fq上一类重根常循环码

记R=Fq+uFq++uk-1Fq,G=R[x]/,且是R中可逆元。定义了从Gn到Rtn的新的Gray映射,证明了J是G上长为n的线性的x-常循环码当且仅当(J)是R上长为tn的线性的-常循环码。使用有限环理论,获得了环R上长为pe的所有的(u-1)-常循环码的结构及其码字个数。特别地,获得了环F2m+uF上长为2e的(u-1)-常循环码的对偶码的结构及其码字个数。推广了环Z2a根负循环码的若干结果。     

牛顿环干涉装置的若干变异结构

综合牛顿环干涉装置的几种变异结构 ,分析了各干涉结构的干涉条件 ,并给出了它们的干涉条纹分布律的统一的数学表达     

Planning of WDM Ring Networks

The rapid introduction of wavelength division multiplexing (WDM) technology to cope with the increased bandwidth requirements of transmission networks has intensified the need for recovery mechanisms at the optical layer. A first step towards survivable optical networking will be seen through the introduction of optical rings. This paper presents different types of optical rings (dedicated and shared protection WDM rings) and the planning issues associated with these WDM rings. In particular, we give mathematical models as well as solution methods for the ring loading and wavelength assignment problem. We compare the wavelength requirement of dedicated and shared protection rings under scenarios with different demand patterns. We also discuss the influence of the WDM equipment cost, and present a mathematical model for the optimization of hybrid networks with both dedicated and shared protection rings.     

活塞环表面处理技术的研究现状及发展趋势

活塞环性能的优劣直接影响到内燃机的整体性能,随着现代内燃机的发展,对活塞环提出了越来越高的要求.阐述了现代活塞环表面处理技术如PVD与CVD镀膜、热喷涂钼涂层、等离子喷涂陶瓷涂层的技术特点,并与电镀铬、表面氮化进行对比,对它们的优缺点进行了分析.展望了现代活塞环表面处理技术的发展趋势.     

金属带式无级变速器钢环组的配合与张应力分布关系的研究

钢环组是金属带的关键组件之一,它的载荷分布关系到金属带的承载能力和使用寿命。本文分析了钢环组配合方式与其张应力分布的关系,提出了采用过盈配合组配钢环能使各层钢环均匀承载的方法,并得到了过盈量的求解算式。