A Cool Brisk Walk Through Discrete Mathematics

A Cool Brisk Walk Through Discrete Mathematics - and its companion site allthemath - are completely-and-forever-free-and-open-source educational materials dedicated to the mathematics that budding computer science practitioners actually need to know. They feature the fun and addictive teaching of award-winning lecturer Dr. Stephen Davies of the University of Mary Washington in Fredericksburg, Virginia

Part grouping for efficient process planning

A framework to provide automated part grouping has been investigated in order to overcome the limitations found in existing part grouping techniques. The work is targeted at: exploration of criteria for feature-based part grouping to make the process planning activity efficient; determination of the optimal number of part families in the part grouping process; development of an experimental hybrid process planning system (HYCAPP); investigation of the effects of improved part grouping on manufacturing cell design. The research work has explored the creation of a feature-based component data model and manufacturing system capability data model, and checked the limitations inherent in existing part grouping techniques i.e. part grouping: around methods; based on part geometry; based on machining processes; and based on machines. [Continues.

Toward a Kripkean Concept of Number

Saul Kripke once remarked to me that natural numbers cannot be posits inferred from their indispensability to science, since we’ve always had them. This left me wondering whether numbers are objects of Russellian acquaintance, or accessible by analysis, being implied by known general principles about how to reason correctly, or both. To answer this question, I discuss some recent (and not so recent) work on our concepts of number and of particular numbers, by leading psychologists and philosophers. Special attention is paid to Kripke’s theory that numbers possess structural features of the numerical systems that stand for them, and to the relation between his proposal about numbers and his doctrine that there are contingent truths known a priori. My own proposal, to which Kripke is sympathetic, is that numbers are properties of sets. I argue for this by showing the extent to which it can avoid the problems that plague the various views under discussion, including the problems raised by Kripke against Frege. I also argue that while the terms ‘the number of F’s’, ‘natural number’ and ‘0’, ‘1’, ‘2’ etc. are partially understood by the folk, they can only be fully understood by reflection and analysis, including reflection on how to reason correctly. In this last respect my thesis is a retreat position from logicism. I also show how it dovetails with an account of how numbers are actually grasped in practice, via numerical systems, and in virtue of a certain structural affinity between a geometric pattern that we grasp intuitively, and our fully analyzed concepts of numbers. I argue that none of this involves acquaintance with numbers

Essentials of computing systems

Computers were invented to “compute“, i.e., to solve all sort of mathematical problems. A computer system contains hardware and systems software that work together to run software applications. The underlying concepts that support the construction of a computer are relatively stable. In fact, (almost) all computer systems have a similar organization, i.e., their hardware and software components are arranged in hierarchical layers (or levels) and perform similar functions. This book is written for programmers and software engineers who want to understand how the components of a computer work and how they affect the correctness and performance of their programs.Publishe

Placeable and localizable elements in translation memory systems

Translation memory systems (TM systems) are software packages used in computer-assisted translation (CAT) to support human translators. As an example of successful natural language processing (NLP), these applications have been discussed in monographic works, conferences, articles in specialized journals, newsletters, forums, mailing lists, etc. This thesis focuses on how TM systems deal with placeable and localizable elements, as defined in 2.1.1.1. Although these elements are mentioned in the cited sources, there is no systematic work discussing them. This thesis is aimed at filling this gap and at suggesting improvements that could be implemented in order to tackle current shortcomings. The thesis is divided into the following chapters. Chapter 1 is a general introduction to the field of TM technology. Chapter 2 presents the conducted research in detail. The chapters 3 to 12 each discuss a specific category of placeable and localizable elements. Finally, chapter 13 provides a conclusion summarizing the major findings of this research project

A Study of Hierarchical Concatenation Networks in the Area of Pattern Recognition

Hierarchical Concatenation Networks (HCN) are inspired by the way humans recognize patterns; i.e. by concatenating small features. In HCNs patterns are split into small parts, and then concatenated and activated in the network’s layers. The research in this thesis investigated and explored feature extraction methods, similarity measures, and classification using HCNs. Results indicate that HCNs can be used in automatic pattern recognition systems with better performance rate on the lower layer than the top layer

Transferring ecosystem simulation codes to supercomputers

Many ecosystem simulation computer codes have been developed in the last twenty-five years. This development took place initially on main-frame computers, then mini-computers, and more recently, on micro-computers and workstations. Supercomputing platforms (both parallel and distributed systems) have been largely unused, however, because of the perceived difficulty in accessing and using the machines. Also, significant differences in the system architectures of sequential, scalar computers and parallel and/or vector supercomputers must be considered. We have transferred a grassland simulation model (developed on a VAX) to a Cray Y-MP/C90. We describe porting the model to the Cray and the changes we made to exploit the parallelism in the application and improve code execution. The Cray executed the model 30 times faster than the VAX and 10 times faster than a Unix workstation. We achieved an additional speedup of 30 percent by using the compiler's vectoring and 'in-line' capabilities. The code runs at only about 5 percent of the Cray's peak speed because it ineffectively uses the vector and parallel processing capabilities of the Cray. We expect that by restructuring the code, it could execute an additional six to ten times faster