On problem transformability in VLSI

The two basic performance parameters that capture the complexity of any VLSI chip are the area of the chip,A, and the computation time,T. A systematic approach for establishing lower bounds onA is presented. This approach relatesA to the bisection flow, . A theory of problem transformation based on , which captures bothAT ² andA complexity, is developed. A fundamental problem, namely, element uniqueness, is chosen as a computational prototype. It is shown under general input/output protocol assumptions that any chip that decides ifn elements (each with (1+)lognbits) are unique must have =(nlogn), and thus, AT²=(n ²log² n), andA= (nlogn). A theory of VLSI transformability reveals the inherentAT ² andA complexity of a large class of related problems.This work was supported in part by the Semiconductor Research Corporation under contract RSCH 84-06-049-6.     

Comparison analysis of formation and some characteristics of microplasma coatings on aluminum and titanium alloys

The electrolyte and parameters of high-voltage anodic-cathodic process, which enable one to apply rather thick (to 340 μm) oxide coatings to titanium alloys, are selected. Characteristics of the coating formation on aluminum and titanium alloys are compared. It is found that, on the titanium alloys, the stage of microarc discharges occurs only at relatively high anodic and cathodic components of the current density. The voltage chronograms and oscillograms also have pronounced specific features. Original Russian Text ? O.P. Terleeva, V.I. Belevantsev, A.I. Slonova, D.L. Boguta, V.S. Rudnev, 2006, published in Zashchita Metallov, 2006, Vol. 42, No. 3, pp. 292–299.     

小波变换在伺服焊枪电极位移曲线分析中的应用

电极位移曲线能够反映出点焊规范参数波动，是一个理想的监控参数。采用离散Daubechies4阶小波对电极位移曲线进行滤波处理，成功地将测量曲线分为电极位移趋势曲线、波动曲线。这两种曲线分别反映了点焊质量的整体质量优劣、过程一致性这两方面特征，提高了位移曲线表征焊接过程的能力，为伺服焊枪的点焊质量控制提供了准确、优良的数据基础。     

绝缘门极双极性晶体管（IGBT）在焊接逆变器中的应用

本文介绍绝缘门极双极性晶体管(IGBT)的基本结构、工作原理、开关特性以及在焊接逆变器中的应用。     

触觉式机器人焊缝跟踪方法

对机器人在焊缝自动跟踪方面进行了研究，介绍了机器人触觉的力传感器结构和使用方法。对力信号进行解耦及信号解算，有效地消除了机器人在工作过程中振动，抖动对力信号的污染，使机器人有能力自动识别，跟踪焊缝及焊枪位置修正，从而保证焊接质量。     

焊缝跟踪技术的研究与展望

本文回顾了电弧焊接的焊缝跟踪技术，并重点对该技术的发展趋势进行了介绍与分析，     

高温钎料PdCu-Ti在氧化铝陶瓷上的润湿性及界面反应

本文采用座滴法试验研究了合金系统ＰｄＣｕ－Ｔｉ在Ａｌ２Ｏ３上润湿性的变化规律，探讨了界面冶金及结合等行为，运用热力学理论对结果进行了分析，随Ｔｉ含量的增加及Ｐｄ含量的减少润湿角逐渐降低，Ｔｉ的加入使界面发生了一个双重变化；液相侧富氧，钛吸收层的生成及随后的固相侧氧化钛的生成，只有界面上生成一氧化钛，才能有较好的润湿行为和较强的结合力。     

从热滤渣中富集提取贵金属

介绍了减压蒸馏脱硫，熔炼富集，高温悬浮氯气浸出处理热滤渣的工艺。其综合利用好，元素硫脱除率〉９２％，贱金属浸出率〉９５％，贵金属回收率〉９９％。贵金属富集物可并入贵金属精炼分离工段处理。