关于Erdōs猜想的推广(英文)

本文证明了关于不相交覆盖系的Erdos猜想的如下推广形式:设g,为Z上的周期函数,正整数n为其正则周期(即n_为其周期且有n_次本原单位根u使得,s=1,2,…k.如果n_1,…,n_k的最小公倍数不是周期函数g=g_1+…+g_的最小正周期,则必有s,t(1≤s,t≤k)使得n_=n_且g≠g.     

镗刀的设计计算

本文论述了固定式镗刀当小刀头轴线与镗杆轴线的夹角小于９０°时，刀孔上平面高于径向平面，在巳知镗刀工作时所需各几何角度时，小刀头上各几何角度的设计计算。利用矢量及座标转换原理，为镗刀几何角度的设计计算推导出了一套精确的计算公式。这对保证镗刀的合理几何角度，提高镗刀的耐用度有重要的意义。     

可化为不含时等效哈密顿量子体系的几何相研究

本文研究了可化为不含时等效哈密顿的量子体系的几何位相问题，给出了处理这一问题的一个新的方法。     

渐开线型插齿刀CAD／CAM几何模型的新探讨

本文针对渐开线型插齿刀设计的传统方案近似性，提出了一种新的设计方案，并推导了相应的ＣＡＤ／ＣＡＭ几何模型，再结合实例表证了新方案的可行性和本文模型的可靠性。     

鱼眼镜头光学设计

鱼眼镜头的视场高达180°或超过180°,可以作为全景电影的摄影和放映镜头,本文介绍了它的结构型式的发展,讨论了它的成象理论,给出了适合它的理想象高公式和光栏球差公式,最后提供了一个实例。     

准精度法解装配尺寸链

本文针对装配尺寸链反计算通常所采用方法的局限性,以公差与配合国家标准中有关标准公差的规定为依据,提出了新的解算方法.     

Geometric integration methods for general nonlinear dynamic equation based on Magnus and Fer expansions

Ithasbeenknownforalongtimethatthesolu tionofthefollowingdifferentialequation :U· =A(t)U ,　U(t0 ) =I ,(1)whereA (t)standsforasufficientlysmoothn×nmatrixorlinearoperator ,canlocallybewrittenintheform[1]U(t ,t0 ) =eΩ(t,t0 ) ,(2 )whereΩisobtainedasaninfiniteseriesΩ(t ,t0 ) =∑∞k =1Ωk(t,t0 ) . (3)Eqs .(2 )and (3)constitutetheso calledMagnusex pansionofthesolutionofthedifferentialequation(1) .EachtermΩkintheseries (3)isamultiplein tegralofcombinationsofnestedcommutators ,anditcanbeobtain…     

Approximation of NURBS Curves and Surfaces Using Adaptive Equidistant Parameterlzatlons

Non-uniform rational B-spline (NURBS) curves and surfaces are very important tools for modelling curves and surfaces. Several important details, such as the choice of the sample points, of the parameterization, and of the termination condition, are however not well described. These details have a great influence on the performance of the approximation algorithm, both in terms of quality as well as time and space usage. This paper described how to sample points, examining two standard parameterizations: equidistant and chordal. A new and local parameterization, namely an adaptive equidistant model, was proposed, which enhances the equidistant model, Localization can also be used to enhance the chordal parameterizatfon, For NURBS surfaces, one must choose which direction will be approximated first and must pay special attention to surfaces of degree 1 which have to be handled as a special case.     

余半单Hopf代数的素数维余表示

设k是特征为0的代数闭域,H为k上的有限维余半单Hop f代数.首先证明了如果H具有型l∶1 m∶2 1∶3 …,则3整除H的维数;其次证明了如果H具有型l∶1 m∶2 … 1∶p …,且H没有9维的单子余代数,则p整除H的维数,其中p为素数.     

藏药"喁"中粗多糖提取和含量分析

本文建立了藏药“喁”中粗多糖含量测定的方法.采用水提醇沉的方法提取粗多糖,酚-硫酸法测定样品中粗多糖的含量.结果发现“喁”中粗多糖收率为16.16%,其中总糖含量为67.90%.