The Theory of Zero-Suppressed BDDs and the Number of Knight's Tours

Zero-suppressed binary decision diagrams (ZBDDs) have been introduced by Minato [14–17] who presents applications for cube set representations, fault simulation, timing analysis and the n-queens problem. Here the structural properties of ZBDDs are worked out and a generic synthesis algorithm is presented and analyzed. It is proved that ZBDDs can be at most by a factor n + 1 smaller or larger than ordered BDDs (OBDDs) for the same function on n variables. Using ZBDDs the best known upper bound on the number of knight's tours on an 8 × 8 chessboard is improved significantly.     

包装行业教育的未来

作为战略因素的包装工业 近年来,整个包装工业的地位突然有了巨大的提高,尤其是在亚洲,如中国.     

The method of angular lines to solve cylindrical electromagnetic boundary-value problems

A method for solving cylindrical electromagnetic boundary-value problems is presented. The method is semidiscrete. The wave equation is written in cylindrical coordinates and a differential-discretizing process is used in angular direction, and in the radial direction the analytic solutions are used. The new method is called the method of angular lines (MAL). To confirm the validity of MAL Dirichlet- and Neumann-type boundary-value problems of a two-dimensional scalar wave equation are investigated. The results show good agreement with previously published results. Advantages and disadvantages of the method are discussed. © 1995 John Wiley & Sons, Inc.     

Current oscillations due to filamentary double injection in diodes with deep levels

Current oscillations occurring in the positive differential resistance region of the d.c. I–V characteristics of Au-compensated n-type silicon pin diodes have been investigated. The experimental results strongly suggest that the current oscillations are caused by the formation of unstable filaments prior to the occurrence of stable filaments which are connected with the negative differential resistance region typical for double injection diodes with deep levels. On the basis of this model the degree of modulation could be increased up to 30% in our diodes.