A complete natural deduction system for the relational calculus

A relational calculus is a formal system in which relation is the fundamental concept. The simplest relational calcu1us, that of ordinary binary relations, was introduced by Tarski in [4]. Tarski's system is essentially an algebra in which the operations are the usual Boolean operations (on sets of ordered pairs) together with the two special operations converse (denoted by u) and composition (denoted by ";" or by juxtaposition)

A proposal to conduct a Caribbean plate project involving the application of space technology to the study of Caribbean geology

The Caribbean plate project is designed to improve current understanding of geological resources and geological hazards within the Caribbean region. Models of mineral occurrence and genesis (including energy resources) on a regional scale, which contribute to nonrenewable resource investigations. Models of lithospheric stress and strain on a regional scale, which contribute to forecasting geological hazards such as earthquakes and major volcanic eruptions are developed. Geological information is synthesize, and research tools provided by space technology the study of the Earth's crust are used. The project was organized in a thematic fashion, to focus on specific geological aspects of the Caribbean plate which are considered to be key factors in developing the types of models described. The project adopts a synoptic perspective in seeking to characterize the three dimensional structure, composition, state of stress, and evolution of the entire Caribbean plate. Geological information derived from analysis of space acquired data is combined with information provided by conventional methods to obtain insight into the structure, composition, and evolution of the Earth's crust. In addition, very long baseline interferometry and laser ranging techniques, which are also based upon the use of space technology, obtain information concerning crustal motion that, in turn, provides insight into the distribution and localization of crustal stress

Programming constructs for nonprocedural languages

In this paper how a pure denotative (nonprocedural) language based on the lambda calculus can be provided with purely denotative analogs of the various constructs - such as while loops, blocks, case statements and the like - of conventional imperative structured programming languages. They can be simulated quite adequately using only two simple tools: phrases, which are compound expressions not unlike blocks, and pronouns, special variables not unlike keywords between which certain relationships are 'understood' to hold

Lucid : a formal system for writing and proving programs

Lucid is both a programming language and a formal system for proving properties of Lucid programs. The programming language is unconventional in many ways, although programs are readily understood as using assignment statements and loops in a 'structured' fashion. Semantically, an assignment statement is really an equation between 'histories', and a whole program is simply an unordered set of such equations. From these equations, properties of the program can be derived by straightforward mathematical reasoning, using the Lucid formal system. The rules of this system are mainly those of first order logic, together with extra axioms and rules for the special Lucid functions. This paper formally describes the syntax and semantics of programs and justifies the axioms and rules of the formal system

The Influence of Royce on the philosophy of Gabriel Marcel

The purpose of this study is to examine the nature of the influence of the philosophy of Josiah Royce (1855-1916) upon me thought of Gabriel Marcel (1889- ). In following the development of Marcel's philosophy it is possible to see how his acquaintance with Royce's philosophy was the intellectual counterpart to the influence on him of his experience as a Red Cross worker during the Great War. Royce's peculiar style of idealism was both the point of contact with Marcel's Idealist background and the source of inspiration for his new philosophical condition. Marcel's main concern was to establish a philosophy of personal relationships which would distinguish personal knowledge from empirical knowledge. He achieved this in his notion of inter subjectivity, with its distinction between I-it relationships and the I-thou encounters. The latter are the realm of all personal values such as fidelity, love and hope. From an analysis of Marcel's study of Royce, made during the Great War, one can see how Marcel was impressed by Royce, particularly by his theory of interpretation. From a survey of both Marcel's notion of inter subjectivity and Royce's theory of interpretation common alms and Interests are clearly seen. But the main Influence of Royce's Work stems from Royce's theory of triadic relations, which made it possible for Marcel to reinstate the central Importance of personal values

Ohio Women Writers Inspire in YA: A Study of Three Authors, their Most Recent Young Adult Texts, and their Paths to Publication

In this project, I will explore the world of YA literature and publishing with a focus on three female authors, Dr. Julie Drew, Rachele Alpine, and Colleen Clayton, and will use their most recently published young adult literature books to further reinforce my research. I will focus on how those texts fit into or go against the current canon of YAL, what common themes these stories touch on, how an adolescent reader might relate to the story and the characters, and other nuances of the texts

Computer-assisted diagnosis of wireless-capsule endoscopic images using neural network based techniques

Computerised processing of medical images can ease the search of the representative features in the images. The endoscopic images possess rich information expressed by texture. In this paper schemes have been developed to extract texture features from the texture spectra in the chromatic and achromatic domains for a selected region of interest from each colour component histogram of images acquired by the new M2A Swallowable Capsule. The implementation of advanced learning-based schemes and the concept of fusion of multiple classifiers have been also adopted in this paper. The preliminary test results support the feasibility of the proposed methodology

Introduction to the Baire space

This report reproduces the chapter 0 of my PhD dissertation, "Reducibility and determinateness on the Baire Space" . I have produced it as a Warwick Theory of Computation report because infinite games and the computational approach to topology presented here is, I feel, very relevant to computer science. The basic connection between topology and computability, explained in section E, is as follows: a function from the Baire space to itself is continuous if it can be computed by a continuously operating numeric 'filter' which has access to a countably infinite database. It used to be thought that infinite computations (not to mention infinite games) were of little relevance to practical computing, which (it was thought) was inherently finitary. The emergence of the dataflow model of computation (among other factors) has changed all this; computer scientists are now keenly interested in the behaviour and properties of continuously operating (nonterminatinq) devices. The entire history of the input to, or output from, such a device will normally be an infinite sequence of finite objects. Such a history can be 'coded up' as an infinite sequence of natural numbers; i.e., as an element of the Baire Space. The study of this space could therefore prove to be as important in computer science as it has already proved to be in (say) statistics. Of course I make no claims to have discovered the material presented here. It has been known for many years now that "computability" and "continuity" are closely related. However, I hope that this report will in a small way help to popularise the 'topological' approach to computation. I would like to thank John Addison for Introducing me to the 'operational' approach to topology. Readers interested in the dissertation itself are referred to Theory of Computation report no 44, which ls a collection of the more important parts

A Complementary Approach for Adaptive and Adaptable Hypermedia: Intensional Hypertext

In this paper we describe a methodology and an authoring/publishing tool for adaptable Web documents (user-determined adaptable Web pages) as a complementary approach to Adaptive Hypermedia. Our approach is based on intensional logic, the logic of assertions and expressions, which vary over a collection of contexts or possible worlds. In our approach the contexts are sets of values for parameters which specify the current user profile as supplied by the current Web page URL, and the latest user input. The author produces generic (multi-version) source in the form of HTML with extra markup delimiting parts that are sensitive (in various ways) to the parameters. This source (in what we call Intensional Markup Language) is translated into a Perl-like language called ISE (Intensional Sequential Evaluator). To generate the appropriately adapted individual pages, the server runs the ISE program in the appropriate context. The program produces HTML that, when displayed in the user's browser, is rendered into the desired adaptation of the requested page. Although this intensional approach was originally designed to work without any explicit user model, we can extend it (and make the documents adaptive as well as adaptable) simply by incorporating a user model that monitors the user and computes some of the profile parameters