An algorithm for network dimensioning under reliability considerations

In this paper we introduce a new methodology to adjust link capacities in circuit switched networks taking into account the costing policy and reliability considerations. This methodology, which is an extension of previous work on reliability evaluation using routing models, is based on a cyclic decomposition algorithm which alternates between a routing subproblem and a link capacity adjustment subproblem. The proposed procedure, which is shown to converge to a global optimum for the dimensioning/routing problem, has been tested on a 14 undirected arc problem for various levels of link failure probability. The numerical results are extremely satisfactory and they demonstrate the usefulness of the proposed method for proper network dimensioning.     

一种实用的尺寸精度查询及标注系统

介绍了以AutoCAD为平台开发的尺寸精度查询及标注系统，给出了系统的结构和主要功能模块的实现方法，实现了系统与AutoCAD的无缝集成，该系统的开发既解决了尺寸精度查询及标注的自动化问题，又为AutoCAD增添了新的功能，更利于进一步发挥CAD的优越性。     

面向尺寸标注的多面体机械零件基本结构分析

根据机械零件计算机辅助造系统提供的信息，对机械零件的基本组成、属性及其尺寸标注原理进行了详尽的分析，给出了零件中基本几何特征的尺寸定位原理和方法，建立了相应的尺寸标注基本数据模型，并已在作者开发的机械智能ＣＡＤ系统中实现。     

一种WCDMA混合业务容量估算方法

WCDMA空中接口能够支持语音和各种数据业务。由于各种业务具有各自的业务特性和QoS要求．业务的混合使得空中接口容量的估算过程变得更为复杂。基于无线资源共享策略计算阻塞概率的方法，提出了一种适合WCDMA混合业务容量估算的方法，同时考虑了非理想功控的影响。通过估算实例表明该方法加快了WCDMA估算速度，并能提供足够的精度。     

基于形体分析的零件尺寸自动标注

采用面向对象的方法建立零件尺寸信息模型,描述面向尺寸标注的零件数据,进而给出了零件尺寸自动标注算法,以及尺寸标注知识的表达方法.详细讨论了算法中基于零件拓扑结构与特征成形等的形体分析,图元尺寸自动生成与特征关联尺寸及冗余尺寸等的识别优化,以及基于特征包围盒的尺寸布局等关键步骤的实现.设计开发了零件尺寸自动标注系统,通过在航空发动机涡轮盘等零件工程制图中的应用,证明该方法能够高效生成准确性高、符合规范且排列整齐的零件尺寸.     

Drawing Recognition for Automatic Dimensioning of Shear-Walls

IntroductionAutomatic drawing for engineering projects is animportant butdifficultproblem for computer- aidedstructural design.In recent years,great progresshas been made in the automatic drawing of beamsand columns,but very little progress has beenmade in the automatic drawing of shear- wallsbecause the dimensioning of shear- walls cannot beautomated.　In dimensioning shear- walls by hand,theengineers can easily decide where to place thedimension lines and texts,but the process cannotbe easil…     

An analytical design method of thin,isotropic press-fit retention sleeve for surface-mounted permanent magnet drives

Electric drives with surface-mounted permanent magnets feature magnet retention sleeves found in the air gap between the rotor and the stator. The design of these components, whose thickness affects the size of the magnetic air gap, has thus significant implications for the overall drive performance. The present work proposes a systematic analytical method for the mechanical design of press-fit retention sleeves for surface-mounted permanent magnet drives. The model relies on the premise that the sleeve is thin and mounted on a much stiffer rotor-magnet assembly. This leads to the assumption of constant thickness before and after the interference fit, as well as the only significant deformation being the hoop extension of the sleeve induced by the press fit. The proposed design method allows for rapid estimations of such sleeve parameters as the thickness and effective overlap, providing critical design points to be verified by subsequent high fidelity approaches. Accordingly, finite-element analysis results are provided as verification of the analytical approach, demonstrating very good agreement between the two approaches.     

Contribution de la logique floue à la représentation des dimensions des pièces d'un ensemble mécaniqueFuzzy logic contribution to the representation of mechanical assembly pieces

The cotation process of a mechanical assembly is a long and complex step of the design. The piece dimensions are often modeled with 2D vectors or torsors. A new representation based on fuzzy logic is presented in this article. The calculus methods of fuzzy dimensions are examined and an application to the extreme positions of a rod-crank system with uncertain dimensions is also presented. To cite this article: C. Lelu, M. Dahan, C. R. Mecanique 330 (2002) 133–140.     

模具零件工程图的孔特征识别与分组统计

提出了面向模具零件工程图的孔特征识别与分组统计方法,采用特征识别实现了尺寸功能语义的再现,基于此进一步实现了孔系的自动分组统计.该方法在AutoCAD软件中利用VisualLISP得到实现.测试结果表明所提出的算法可以很好地解决尺寸完整性问题,完善了模具零件尺寸自动标注功能.     

AutoCAD中图纸空间的尺寸标注

讨论了在AutoCAD中将三维实体转换成二维视图后，有关图纸空间中的线性尺寸和圆弧尺寸的标注问题。