轴承套圈端面磨削方法与加工质量的关系

双端面磨削是轴承行业普遍采用的一种加工方法.本文通过对双端面磨削的加工机理进行分析,指出不同的加工方法对产品质量的影响是不同的;同时对比分析两种磨削方式的优劣,针对不同的产品,提供了合理加工方法的选择途径.     

基于PLM系统多专业的BOM多视图应用

该文以某公司实施项目为例,针对其产品变化快、衍生多的特性,提出优化实施方案,通过PLM系统实现BOM多视图管理,达到BOM数据准确性和一致性,减少重复劳动,权责清晰,变更得到有效管理,提高产品开发效率。从发现问题到解决痛点一一列举,为同行业企业数字化转型升级之路提供参考。     

产品生命周期中的单/多层BOM表示与应用

在产品生命周期中，BOM作为描述产品结构与配置关系的表单，以多视图形式描述了产品形态的变化过程。许多文献对产品生命周期中BOM的某一视图或某几个视图进行了表述，但对产品生命周期BOM全过程的演进与内在联系，还缺少详尽的研究。本文提出一种面向产品生命周期管理的单层BOM基本视图和多层BOM表达技术，揭示了产品生命周期中BOM多视图的内在联系，并在汽车产品的生命周期管理中得到应用。     

五角棱镜的角度制造误差对波前测量的影响

从光学平行差入手,导出了有角度制造误差的五角棱镜的像方坐标系和作用矩阵,分析了角度制造误差引起的扫描激光束转向的波前误差,提出了调整五角棱镜的依据,有利于减小角度制造误差对大口径透镜望远镜波前测量的影响。     

基于分析法的平行度误差计算机数据处理

利用计算机对误差测量数据进行处理,可以提高形状和位置误差评定精度,提高数据处理速度.提出了基于分析法的按最小包容区域准则评定直线度误差和平行度误差的设计思想和基本算法,用VC 开发了误差评定软件,给出了关键部分程序代码.通过应用实例,验证了该算法的可行性和正确性.     

液浮靶标靶板的设计与实验

为了设计光轴一致性检测中用于基准光轴空间角监测的液浮空间角靶标,确定了液浮靶板选择原则。首先,利用流体力学对靶板在浮液中的横摇固有周期进行了分析;然后,结合谐振等相关知识,分析了靶板横摇固有周期与浮液震荡周期不同比值下,靶板的稳定情况;最后,确定了靶板横摇固有周期应大于浮液震荡周期的靶板选择原则。通过对不同厚度的圆柱形靶板及半球形靶板的分析,选择横摇固有周期较大的半球形靶板,并通过实验验证了所确定的靶板选择原则的正确性。     

细粒度并行与多线程计算

为实现高性能有必要采用细粒度的并行，但必须解决其中增大的通信开销问题。多线程计算不仅用来实现细粒度的并行，合理的调度策略还有助于隐藏通信延迟。但其中存在着线程切换开销的问题，多线程处理器可能是一种解决办法。     

一个VLIW体系结构的单片多处理机

本介绍一个采用ＶＬＩＷ超长指令字体系结构的高性能单片多处理机，在这个体系结构中采用流水寄存器堆来消除循环程序内的数据相关，从而使程序能够在指令级以极高的并行度并行运行。模拟实验结果表明这个体系结构具有很高的运算速度和很好的性能价格比。     

Parallel context-sensitive compilation

The searching power of massively parallel associative computers is an under used and under investigated capability that can be used to facilitate software development. This paper describes the development of a context sensitive compiler for pattern-matching languages using that searching power. The described compiler was implemented on the STARAN parallel computer and the compiled OPS5 programs were also executed on the STARAN obtaining an estimated throughput of 6000 rules per second. The described compilation of production rules into equivalent procedural rules is completely data parallel, with the degree of parallelism depending on the number of tokens in the program being compiled. During any one step of the context-sensitive analysis, the entire program is processed in constant time.     

Architectural support for inter-stream communication in an MSIMD system

This paper considers hardware support for the exploitation of control parallelism on data parallel architectures. It is well known that data parallel algorithms may also possess control parallel structure. However, the splitting of control leads to data dependency and synchronization issues that were implicitly handled in conventional SIMD architectures. These include synchronization of access to scalar and parallel variables, and synchronization for parallel communication operations. We propose a sharing mechanism for scalar variables and identify a strategy which allows synchronization of scalar variables between multiple streams. The techniques considered are based on a bit-interleaved register file structure which allows fast copy between register sets. Hardware cost estimates and timing analyses are provided, and comparison with an alternate scheme is presented. The register file structure has been designed and simulated for the HP 0.8μm CMOS process, and circuit simulation indicates access times are less than six nanoseconds. In addition, the impact of this structure on system performance is also studied.