An Introduction to pulp for Python Programmers

Pulp-or (referred to as pulp for the rest of this paper) is a linear programming framework in Python. Pulp is licensed under a modified BSD license. The aim of pulp is to allow an Operations Research (OR) practitioner or programmer to express Linear Programming (LP), and Integer Programming (IP) models in python in a way similar to the conventional mathematical notation. Pulp will also solve these problems using a variety of free and non-free LP solvers. Pulp models an LP in a natural and pythonic manner.This paper is aimed at the python programmer who may wish to use pulp in their code. As such this paper contains a short introduction to LP models and their uses

Artificial Intelligence Techniques for Automatic Reformulation and Solution of Structured Mathematical Models

Complex, hierarchical, multi-scale industrial and natural systems generate increasingly large mathematical models. Practitioners are usually able to formulate such models in their "natural" form; however, solving them often requires finding an appropriate reformulation to reveal structures in the model which make it possible to apply efficient, specialized approaches. The search for the "best" formulation of a given problem, the one which allows the application of the solution algorithm that best exploits the available computational resources, is currently a painstaking process which requires considerable work by highly skilled personnel. Experts in solution algorithms are required for figuring out which (formulation, algorithm) pair is better used, considering issues like the appropriate selection of the several obscure algorithmic parameters that each solution methods has. This process is only going to get more complex, as current trends in computer technology dictate the necessity to develop complex parallel approaches capable of harnessing the power of thousands of processing units, thereby adding another layer of complexity in the form of the choice of the appropriate (parallel) architecture. All this renders the use of mathematical models exceedingly costly and difficult for many potentially fruitful applications. The \name{} environment, proposed in this Thesis, aims at devising a software system for automatizing the search for the best combination of (re)formulation, solution algorithm and its parameters (comprised the computational architecture), until now a firm domain of human intervention, to help practitioners bridging the gap between mathematical models cast in their natural form and existing solver systems. I-DARE deals with deep and challenging issues, both from the theoretical and from an implementative viewpoint: 1) the development of a language that can be effectively used to formulate large-scale structured mathematical models and the reformulation rules that allow to transform a formulation into a different one; 2) a core subsystem capable of automatically reformulating the models and searching in the space of (formulations, algorithms, configurations) able to "the best" formulation of a given problem; 3) the design of a general interface for numerical solvers that is capable of accommodate and exploit structure information. To achieve these goals I-DARE will propose a sound and articulated integration of different programming paradigms and techniques like, classic Object-Oriented programing and Artificial Intelligence (Declarative Programming, Frame-Logic, Higher-Order Logic, Machine Learning). By tackling these challenges, I-DARE may have profound, lasting and disruptive effects on many facets of the development and deployment of mathematical models and the corresponding solution algorithms

The Characterisation of Porous Media

This thesis describes the characterisation of a range of sol-gel silicas, mainly by the physical techniques of NMR cryoporometry, density and imbibation measurements and Small Angle Neutron Scattering. The developments made to these techniques as part of this work include Construction of the frst full cool/warm cycle automated NMR cryoporometer, with continual pore size distribution graphing. Calibration of melting point constants with respect to gas-adsorption and neutron scattering. Detailed characterisation of the thermal properties of the cryoporometer. Development and measurement of the rst multi-dimensionally resolved pore size maps by NMR cryoporometry. Demonstration that simple density and imbibation measurements can, when combined with models, provide a wealth of information concerning the silicas. Development of novel continuous medium Monte-Carlo integration methods to calculate the solid-solid density correlation function for porous media, showing excellent agreement with experimental SANS results. In particular, with the second point, there has been an attempt to use SANS to provide an absolute calibration scale for pore size, nominally given by gas-adsorption

The characterisation of porous media

This thesis describes the characterisation of a range of sol-gel silicas, mainly by the physical techniques of NMR cryoporometry, density and imbibation measurements and Small Angle Neutron Scattering. The developments made to these techniques as part of this work include Construction of the frst full cool/warm cycle automated NMR cryoporometer, with continual pore size distribution graphing. Calibration of melting point constants with respect to gas-adsorption and neutron scattering. Detailed characterisation of the thermal properties of the cryoporometer. Development and measurement of the rst multi-dimensionally resolved pore size maps by NMR cryoporometry. Demonstration that simple density and imbibation measurements can, when combined with models, provide a wealth of information concerning the silicas. Development of novel continuous medium Monte-Carlo integration methods to calculate the solid-solid density correlation function for porous media, showing excellent agreement with experimental SANS results. In particular, with the second point, there has been an attempt to use SANS to provide an absolute calibration scale for pore size, nominally given by gas-adsorption

Air Traffic Management Abbreviation Compendium

As in all fields of work, an unmanageable number of abbreviations are used today in aviation for terms, definitions, commands, standards and technical descriptions. This applies in general to the areas of aeronautical communication, navigation and surveillance, cockpit and air traffic control working positions, passenger and cargo transport, and all other areas of flight planning, organization and guidance. In addition, many abbreviations are used more than once or have different meanings in different languages. In order to obtain an overview of the most common abbreviations used in air traffic management, organizations like EUROCONTROL, FAA, DWD and DLR have published lists of abbreviations in the past, which have also been enclosed in this document. In addition, abbreviations from some larger international projects related to aviation have been included to provide users with a directory as complete as possible. This means that the second edition of the Air Traffic Management Abbreviation Compendium includes now around 16,500 abbreviations and acronyms from the field of aviation