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1	Electrical Characterization and Modeling of Plated Through Holes in Organic Substrate Cheng, Hung-Hsiang 12 July 2007 (has links) This thesis focuses on the structures of plated through holes in organic substrate, and discusses the high-frequency electrical characteristics of various plated through hole structures. This thesis consists of four parts. The first part introduces various kinds of vias in multilayer substrate. This content includes substrate drilling processes and capabilities, and discussions on plated through hole structures and their manufacture concerns. The second part focuses on actual measurement of plated through holes, and introduces high-frequency double-side probing technique. The difference from traditional high-frequency coplanar probing measurement is also discussed. The third part focuses on the high-frequency simulation by full-wave software ¡V Ansoft HFSS, and discusses the effects of various excited source and model structures on simulations. Part4 focuses on developing the broadband equivalent circuit model based on the physical structures, and discusses the electrical characterization of different plated through holes, and provides the related design concept. Plated Through Holes Double-side Measurement Equivalent Circuit Model
2	Interval Matching and Control for Hexahedral Mesh Generation of Swept Volumes Shepherd, Jason F. 01 April 1999 (has links) (PDF) Surface meshing algorithms require certain relationships among the number of intervals on the curves that bound the surface. Assigning the number of intervals to all of the curves in the model such that all relationships are satisfied is called interval assignment. Volume meshing algorithms also require certain relationships among the numbers of intervals on each of the curves on the volume. These relationships are not always captured by surface meshing requirements. This thesis presents a news technique for automatically identifying volume constraints. In this technique, volume constraints are grouped with surface constraints and are solved simultaneously. A sweepable volume has source, target and linking surfaces. The technique described in this thesis uses graph algorithms to identify independent, parallel sets of linking surfaces, and determine if they correspond to through-holes or blind-holes. For blind-holes, the algorithm generates constraints that prevent the hole from being too deep in interval parameter space and, thus, penetrating opposite target surfaces. For each linking set, the adjoining source and target surfaces are partially ordered by the structure of the linking set. A small set of representative paths for each linking set is found, and the representative paths for all linking sets are gathered and distilled by Gaussian elimination into a small set of constraints. Interval Matching Control Hexahedral Mesh Generation Swept Volumes Surface Algorithms Curves Model Assignment Relationships Sweep Linking Through-holes Blind-Holes Constraints Civil and Environmental Engineering

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Electrical Characterization and Modeling of Plated Through Holes in Organic Substrate

Interval Matching and Control for Hexahedral Mesh Generation of Swept Volumes