The Principle of Circular and Cumulative Causation: Myrdal, Kaldor and Contemporary Heterodox Political Economy

The first main section studies the similarities and differences between the Myrdalian and Kaldorian CCC frameworks. The second section develops a general system model of integration between the two traditions. There is a large measure of continuity between the two CCC approaches; they complement each other. Myrdalian CCC concentrates on the social provisioning aspect of development, while Kaldorian CCC centres on demand-supply relationships linked to the manufacturing sector. Linking both CCC approaches in an integrative model enhances our understanding of development and growth dynamics, and contributes to the development of institutional-evolutionary political economy. The third section illustrates a contemporary application of CCC through an investigation of the dynamic forces expanding the scope, network interaction and conceptual-empirical edifice of heterodox political economy

Observations and models of thermal emission from natural and man made objects

This thesis is concerned with the investigation of the measurement of radiometric temperatures of various terrestrial surfaces, and the implementation and validation of a number of mathematical models to represent and predict the thermal behaviour of such surfaces under various conditions. Data can be acquired for radiation in a number of wavebands. Three radiometer systems built in Durham have been upgraded to allow measurements to be made in the 2-5pm and 8-14 µm wavebands. The refurbishment of these systems is described. An empirical model has been developed in Durham to describe the thermal behaviour of surfaces in terms of meteorological parameters. An experiment was carried out to determine the validity of this model for dealing with thermally light surfaces such as textiles. The analysis of the results from this investigation is presented. Detection modelling involves the production of mathematical models to describe the behaviour of all components in a system, including the surface under observation, atmosphere and the detector. A number of published detection models are discussed, together with other models which describe the behaviour of one particular component, and which could be combined to produce a detection model for a particular purpose. One particular detector/atmosphere model, SenSAT-3, is the subject of a detailed evaluation, with a view to integrating it with the Durham General Purpose Model for surface temperature to produce a complete detection model. The final chapter summarizes the current status of the work, and indicates possible directions for the future, including the development of a detection model based on the characteristics of the radiation thermometers installed in the Durham-built radiometers

Correlation of laboratory and installed drainage system solid transport measurements

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The transport of solids in 'horizontal' above ground drainage pipes was the subject of an investigation, based upon the measurement of both sterile 'model' solid velocity and 'live' waste load velocity, aimed at the establishment of a sound basis for the development of a comprehensive empirical drainage design method linked directly to installed drainage system solid transport measurements. Initial laboratory investigations were directed towards the assessment of various 'model' solid materials, with regard to comparative potential use with respect to drainage research. Results suggested a 'calibration' approach to the development of a design method to be a viable proposition, while a 'direct simulation' approach was found to be impracticable. Two installed branch drainage systems were monitored which served male and female W.C. cubicles in the entrance waiting-area of a large London hospital. A considerable body of data was compiled with respect to both facility usage patterns and drainage system loading. Transport performance data, classified according to waste load type, was processed to yield comparisons to the general form of relationships previously reported in relation to 'model' solid transport. It was concluded that the proportional rate of occurrence of the different types of waste load must be a prime consideration in any design method, and the premise that solid deposition should be avoided was confirmed. Solid transport mechanisms, as associated with each of the different types of 'live' waste load material and sterile 'model'. were detailed, and the relevance to 'live' waste load performance, of previous 'model' solid transport equations (which suggest 'linear' deceleration over substantial pipe lengths), was demonstrated. The study was concluded with the presentation of specific design performance recommendations, based upon the installed drainage system transport measurements, which data may be employed, initially, as the basis for a 'calibration' approach to laboratory based drainage research, and subsequently, as the basis for a comprehensive empirical drainage design method.The work reported was supported by D. H. S. S. Commission Number 981/-/188, and was conducted within the Department of Building Technology at Brunel University

Applying Model-Driven Engineering to Development Scenarios for Web Content Management System Extensions

Web content management systems (WCMSs) such as WordPress, Joomla or Drupal have established themselves as popular platforms for instantiating dynamic web applications. Using a WCMS instance allows developers to add additional functionality by implementing installable extension packages. However, extension developers are challenged by dealing with boilerplate code, dependencies between extensions and frequent architectural changes to the underlying WCMS platform. These challenges occur in frequent development scenarios that include initial development and maintenance of extensions as well as migration of existing extension code to new platforms. A promising approach to overcome these challenges is represented by model-driven engineering (MDE). Adopting MDE as development practice, allows developers to define software features within reusable models which abstract the technical knowledge of the targeted system. Using these models as input for platform-specific code generators enables a rapid transformation to standardized software of high quality. However, MDE has not found adoption during extension development in the WCMS domain, due to missing tool support. The results of empirical studies in different domains demonstrate the benefits of MDE. However, empirical evidence of these benefits in the WCMS domain is currently lacking. In this work, we present the concepts and design of an MDE infrastructure for the development and maintenance of WCMS extensions. This infrastructure provides a domain-specific modelling language (DSL) for WCMS extensions, as well as corresponding model editors. In addition, the MDE infrastructure facilitates a set of transformation tools to apply forward and reverse engineering steps. This includes a code generator that uses model instances of the introduced DSL, an extension extractor for code extraction of already deployed WCMS extensions, and a model extraction tool for the creation of model instances based on an existing extension package. To ensure adequacy of the provided MDE infrastructure, we follow a structured research methodology. First, we investigate the representativeness of common development scenarios by conducting interviews with industrial practitioners from the WCMS domain. Second, we propose a general solution concept for these scenarios including involved roles, process steps, and MDE infrastructure facilities. Third, we specify functional and non-functional requirements for an adequate MDE infrastructure, including the expectations of domain experts. To show the applicability of these concepts, we introduce JooMDD as infrastructure instantiation for the Joomla WCMS which provides the most sophisticated extension mechanism in the domain. To gather empirical evidence of the positive impact of MDE during WCMS extension development, we present a mixed-methods empirical investigation with extension developers from the Joomla community. First, we share the method, results and conclusions of a controlled experiment conducted with extension developers from academia and industry. The experiment compares conventional extension development with MDE using the JooMDD infrastructure, focusing on the development of dependent and independent extensions. The results show a clear gain in productivity and quality by using the JooMDD infrastructure. Second, we share the design and observations of a semi-controlled tutorial with four experienced developers who had to apply the JooMDD infrastructure during three scenarios of developing new (both independent and dependent) extensions and of migrating existing ones to a new major platform version. The aim of this study was to obtain direct qualitative feedback about acceptance, usefulness, and open challenges of our MDE approach. Finally, we share lessons learned and discuss the threats to validity of the conducted studies

Investigating the Weddell Sea Anomaly using TIE-GCM

The ionosphere is a region of Earth’s upper atmosphere that is embedded in the thermosphere and parts of the exosphere and mesosphere. The ionosphere is a layer of electrons and electrically charged atoms and molecules that are created by atmospheric absorption of solar radiation. It is subdivided into many layers but for this report, only the F-layer will be of interest. In the F-layer, extreme ultraviolet (EUV) solar radiation ionizes atomic oxygen and in this layer, an intriguing feature occurs. This feature involves an anomalous evening phenomenon over a fixed geographic location, where the electron density during the nighttime is more than twice as large than at noon. This phenomenon takes place during the summer and is visible in the southern hemisphere. This intriguing phenomenon is known as the Weddell Sea Anomaly (WSA). In an effort to understand this anomalous phenomenon, we investigated whether the Thermosphere-Ionosphere-Electrodynamic General Circulation Model (TIE-GCM) could successfully replicate the WSA observations. TIE-GCM is available for runs-on-request at the Community Coordinated Modeling Center (CCMC). Using the CCMC, we preformed TIE-GCM model runs for the conditions foreseeable for the development of the WSA. MATLAB was used to illustrate output data from TIE-GCM. The data obtained from TIE-GCM was also compared and contrasted to other empirical based model data such as: Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) and Mass-Spectrometer-Incoherent-Scatter (MSIS) E-90 for further investigation of TIE-GCM’s ability to replicate the WSA

Metalogic and the psychology of reasoning.

The central topic of the thesis is the relationship between logic and the cognitive psychology of reasoning. This topic is treated in large part through a detailed examination of the recent work of P. N. Johnson-Laird, who has elaborated a widely-read and influential theory in the field. The thesis is divided into two parts, of which the first is a more general and philosophical coverage of some of the most central issues to be faced in relating psychology to logic, while the second draws upon this as introductory material for a critique of Johnson-Laird's `Mental Model' theory, particularly as it applies to syllogistic reasoning. An approach similar to Johnson-Laird's is taken to cognitive psychology, which centrally involves the notion of computation. On this view, a cognitive model presupposes an algorithm which can be seen as specifying the behaviour of a system in ideal conditions. Such behaviour is closely related to the notion of `competence' in reasoning, and this in turn is often described in terms of logic. Insofar as a logic is taken to specify the competence of reasoners in some domain, it forms a set of conditions on the 'input-output' behaviour of the system, to be accounted for by the algorithm. Cognitive models, however, must also be subjected to empirical test, and indeed are commonly built in a highly empirical manner. A strain can therefore develop between the empirical and the logical pressures on a theory of reasoning. Cognitive theories thus become entangled in a web of recently much-discussed issues concerning the rationality of human reasoners and the justification of a logic as a normative system. There has been an increased interest in the view that logic is subject to revision and development, in which there is a recognised place for the influence of psychological investigation. It is held, in this thesis, that logic and psychology are revealed by these considerations to be interdetermining in interesting ways, under the general a priori requirement that people are in an important and particular sense rational. Johnson-Laird's theory is a paradigm case of the sort of cognitive theory dealt with here. It is especially significant in view of the strong claims he makes about its relation to logic, and the role the latter plays in its justification and in its interpretation. The theory is claimed to be revealing about fundamental issues in semantics, and the nature of rationality. These claims are examined in detail, and several crucial ones refuted. Johnson- Laird's models are found to be wanting in the level of empirical support provided, and in their ability to found the considerable structure of explanation they are required to bear. They fail, most importantly, to be distinguishable from certain other kinds of models, at a level of theory where the putative differences are critical. The conclusion to be drawn is that the difficulties in this field are not yet properly appreciated. Psychological explantion requires a complexity which is hard to reconcile with the clarity and simplicity required for logical insights

INVESTIGATION OF LANGMUIR PROBES IN NON-MAXWELLIAN PLASMA USING PARTICLE-IN-CELL (PIC) MODELING

This dissertation explores the development of a capability for simulating the plasma dynamics of Langmuir probes (LP) in complex plasmas where the velocity distributions are non-equilibrium and the electron energy spectrum is non-Maxwellian with respect to laboratory and space experiments. The results of this investigation are interpreted to give recommendations for design and use of LPs. This work is conducted using computational techniques to create the exact plasma conditions of the experimental testing environments. The investigations address the following topics: development of a technique to model non-Maxwellian physics, modification of a baseline-technique and optimization of it for this application, creation of three-dimensional PIC code to include non-Maxwellian physics, evaluation of effectiveness of enhanced PIC simulations, demonstration of use of enhanced PIC code to conduct and simulate LP experiments in non-ideal conditions such as in the EP thruster. Major results can be summarized as follows: PROBEPIC (PIC code) is modified for interpreting data obtained using an electrostatic-probe in an ion-beam to implement OML (thick-sheath) and SL (thin-sheath) current-collection theories. PROBEPIC was modified to model the non-Maxwellian plasmas, and test-cases are presented to validate the simulation against published empirical data. General equations for current-collection and I-V curves for cylindrical, planar and spherical LP in isotropic and anisotropic non-Maxwellian plasmas are examined. Distribution functions are introduced as a method of measuring the deviation from Maxwellian. Existing non-Maxwellian techniques (i.e., Druyvesteyn, bi-Maxwellian) were modified to model the environment around LP in an EP system. The EEDF has been investigated with LP to overcome some limitations of Druyvesteyn method. The EEDF changes from Druyvesteyn to bi-Maxwellian with decreasing pressure. Therefore, bi-Maxwellian method was also implemented in the system to obtain utmost results in modelling non-isotropic plasmas. This innovative model, which was then integrated into PROBEPIC, was used to simulate operation of LP in a series of validation and demonstration cases. The effective-Te, n, and Vp were obtained from the LP simulations, and I-V traces were created. The code can predict the high-energy ions, and experimental measurement of the EEDF, providing useful information for the development of a state-of-the-art new plasma and EP diagnostic capabilities