Construction companies are operating within an increasingly competitive environment. Work often has to be tendered for on a very low profit basis. If the tender is too high, work is lost. If too low the contract may be won, but the job completed at a loss, unless more effective working methods can be found. Plans are used throughout the construction industry to allocate resources and schedule work. Yet, the planning tools used; Gantt chart, PERT and Queuing theory to name but a few, represent jobs as if they are static in duration, which in the complex, dynamic construction environment are clearly inappropriate. The EPSRC fuelled interest in developing a simulation methodology by suggesting that the construction industry could be considered similar to the traditional manufacturing industry. The manufacturing industry faced similar production dilemmas, work was completed but using inefficient resource configurations, causing bottlenecks, increased work-in-progress leading to higher costs. To reduce number of problems the manufacturing industry sought to utilise and develop a planning technique that had the capacity for modelling the dynamic nature of the industry. Discrete-event simulation enables the problems associated with manufacturing to be anticipated and minimised, as opposed to constantly fire-fighting. Since using simulation has accrued such impressive benefits within the manufacturing industry it is therefore not without credence to believe that the construction industry could also obtain saving from embracing this management tool. Simulation has been applied to model a number of scenarios within the construction industry. Similarities between the applications were sought and an area for further development was identified. A problem was modeled using the most frequently encountered simulation paradigms found in the manufacturing and construction industries, 'Activity cycle' and 'Process based'. Of the two methodologies, 'Process based' was selected for the development of further models. A conclusion drawn from the research is that simulation is not being utilized within the construction industry due to the perception that it requires an excessive use of resources. The research project identified that the model building process may be simplified through the development of generic simulation modules. These generic modules enable a simulation model to be developed quickly and easily by a non-simulation practitioner. The generic modules can be connected to represent the layout of an earthmoving operation. A host of scenarios can thus be modeled with the minimum of time and effort. To ensure that only significant data and process logic was collected and included within the modules the experimental methodology factor analysis was employed. Using this experimental technique, the relationship between and significance of ten different factors were established. Further experiments were performed on the most significant factors establishing an appropriate level of detail for those factors. It was beyond the scope of this thesis to develop modules for every conceivable construction process. Therefore, a methodology is given documenting the development of the chosen construction processes.

Excessive ammonia (NH3) emission, originating largely from agriculture, can affect water, air and soil quality, and through these, endanger ecosystem and human health. Since NH3 emission is strongly dependent on temperature and also influenced by other meteorological variables, the question arises: how will NH3 emission alter in a changing climate? A way to address this question and predict the subsequent environmental consequences is to construct meteorology-driven models of NH3 emission from every agricultural source. Furthermore, NH3 emission is a highly localised and dynamic process. The focus of this thesis is NH3 emission from grazing. In the first stage a new process-based model for NH3 emission from a urine patch was developed. The GAG model (Generation of Ammonia from Grazing) is capable of simulating the TAN (total ammoniacal nitrogen) and the water content of the soil under a urine patch and also soil pH dynamics. In the second stage, GAG was applied to the scale of a grazed field, combining multiple simulations of the patch-scale model including both urine-affected and unaffected (“clean”) areas. The modelled NH3 fluxes were found to be in good agreement with the observations for both model types. The sensitivity of NH3 flux was assessed to various soil physical and chemical parameters for both the patch and the field scale models. It was found that ammonia volatilization from a urine patch could be influenced by the possible restart of urea hydrolysis after a rain event as well as carbon-dioxide emissions from the soil. Over the field scale, it was shown that the temporal evolution of the NH3 exchange flux was dominated by the NH3 emission from the patches within the field. The results also suggested that NH3 fluxes over the field in a given day could be considerably affected by the NH3 emission from urine patches deposited several days earlier. In the last stage of the work, a comprehensive sensitivity analysis was carried out with a special focus on temperature, for both versions of the GAG model. It was shown that due to the different governing dynamics over the patch and the field scale, the temperature-dependence of NH3 exchange is stronger over the field scale. It was also concluded that the temperature-dependence of NH3 exchange is stronger if the sinks of NH3 are stronger within the system. Finally, it was found, that Q10, a widely-used metric to express the relative increase of trace gas emissions over a range of 10 °C, is influenced by the length of the period of investigation and the initial value of the temperature range.

No description available.

No description available.

In the UK, nearly half of the plants short listed for high conservation priority in the UK Biodiversity Action Plan are found in taxonomically complex groups. It is thought that a shift from species- to process-based conservation strategies, aimed at conserving the processes that generate diversity as opposed to simply the end product of these dynamic interactions, may benefit these groups. One group for which this strategy has been proposed is tetraploid Euphrasia. The underlying taxonomic complexity in this group is hypothesised to arise via breeding systems, hybridisation and local ecotypic adaptation. The goal of this thesis is to use morphological, ecological and molecular marker data to examine taxon limits and evolutionary processes in order to further understand the mechanisms involved in maintaining species boundaries and generating taxonomic complexity in tetraploid Euphrasia. This will not only make conservation in this group more effective, but will also provide a broader insight into some of the processes involved in plant speciation. A detailed study of two widespread, small flowered, tetraploid taxa, E. micrantha and E. scottica, showed that offspring are almost exclusively the result of self-fertilization. These taxa maintain distinctive morphologies, habitat preferences and chloroplast DNA variation throughout their range, suggesting that they represent coherent lineages within Scotland. As in other widespread inbreeding species, there are high levels of microsatellite differentiation among different populations of the same species. In northwest Scotland three complex populations of tetraploid Euphrasia were identified which comprised an array of many different morphs (recognised species, and putative hybrids). Analysis of chloroplast and microsatellite markers suggests that these different morphs represent distinct genetic groups. Within each site there is evidence both for habitat heterogeneity, and for association of morphs with this habitat variation. Intermediate morphs were not simple F1 hybrids, but are likely to have originated via hybridisation and subsequent selfing, surviving as independent recombinant lines, perhaps specialised for habitat types different from that of their progenitor parents. These stable morphs of hybrid origin could represent groups with adaptive potential that may result in the origin of a novel Euphrasia species. It will be important to further examine the processes involved in generating novel diversity in Euphrasia. For the time being, these complex populations must be recognised as sites requiring special protection within the context of a process-based conservation strategy.

Ecological sites and state-transition models (STMs) have become the preferred means of summarizing plant community dynamics on distinctive types of rangeland. Ecological sites classify rangeland types based on soil-geomorphic and climatic conditions capable of producing a known plant community, while a STM depicts the vegetation dynamics of an ecological site. STMs are usually based on expert opinion rather than site-specific data; however, if they are to gain credibility, STMs must accurately describe the processes that drive plant community dynamics. This study examined three ways of developing process-based STMs using three levels of commonly collected field data. We began by taking field inventories of three ecological sites already mapped in northwestern Utah: Loamy Bottom, Mountain Gravelly Loam, and Upland Loam. The Loamy Bottom site was ideal for developing a data-rich, process-based STM because 1) the site concepts were well-defined, 2) the site was easy to recognize, 3) potential states and transitions had already been hypothesized, and 4) the site was easily accessible. The Loamy Bottom study was designed to link plant community structural indicators to measurable indicators of ecological process. Principal components analysis and cluster analysis were used to classify 14 study plots into four distinct states. Simple linear regression showed relationships between perennial grass cover, perennial canopy gaps, and soil organic carbon. Analysis of variance (ANOVA) linked four general vegetation classes to soil stability measurements. The resulting STM describes the structure and function of four alternative states. The other two STMs, developed for the Mountain Gravelly Loam and Upland Loam ecological sites, used less-intensive data collection methods. Rangeland health assessments, used for the Upland Loam STM, are useful for refining initial ecological site and STM concepts, documenting states, hypothesizing transitions, and locating study locations for future research. Quantitative production and cover estimates, used for the Mountain Gravelly Loam STM, are useful for describing the structure of states, but structural indicators must be coupled with process measurements, as with the Loamy Bottom STM to understand the drivers of state change. A coordinated data collection effort is needed to produce STMs that accurately depict the plant community dynamics of ecological sites.

This paper reports on a research project in which a group of teachers in a pre-school teacher education programme based at a “satellite” study centre in a distant rural area used a student-centred learning approach as a means to bridge the distance in the social relationship. A qualitative approach was taken that aimed to develop a greater understanding of the teacher-student relationship through research questions addressing the student role, the learning process and the assessment process. A didactical design for process-based assessment was developed and structured into three phases involving questions about the students’ previous knowledge, reflections and learning. Data were collected through in-depth interviews. The material was analysed using inductive thematic analysis. The underpinning principles of power and control were helpful for understanding the social relations in the teacher-student relationship in this online context. The results indicate a conflict between the student-centred curriculum and traditional beliefs in the teacher-student relationship.

The current state of the art in water quality profiling is reviewed to lay a foundation in addressing concerns over poor data in developing countries which has not been adequately covered by previous models. A particular focus is made on Ogbese River, southwest Nigeria as a case study. A process-based model with data-filling capability is projected which transforms processes into an event as a reasonably easy way for assessing and predicting river-water quality in the event of constraints in data collection. The structure of the study involves: (i) hydrologic modelling, (ii) hydraulic load modelling and (iii) instream water quality modelling. The hydrologic modelling assesses and makes use of satellite based rainfall estimates subject to processing and reliability tests. A modification to the conceptual relationship of rainfall distribution frequency which makes the model output sensitive to the season was derived. The hydraulic load modelling integrates diffuse sources of pollutant as spatial data in combination with the catchment runoff. A distance decay weighing factor was introduced into the export coefficient to better determine the effective load delivered into the stream. The utility of the model, implemented on WASP platform, was demonstrated by showing how it can be used for scenario testing. Different modelling concepts were evaluated in view of their ability to produce predictions under changing circumstances using the predictions as guide to management. This study promotes a knowledge base in water quality processes by evaluation of the processes which lead to the end product rather than using data monitoring. The study structures understanding of the phenomena that characterises river water quality and tailors it towards regulatory applications and catchment planning. It, also, provides a sustainable strategy to predict the river water quality, evaluate the risks, and take proactive action in setting up an early warning system, for data-poor regions.

Current computing hardware supports parallelism at various levels. Conventional programming techniques, however, do not utilise efficiently this growing resource. This thesis seeks a better fit between software and current hardware while following a hardware-agnostic software development approach. This allows the programmer to remain focussed on the problem domain. The thesis proposes process-based problem decomposition as a natural way to structure a concurrent implementation that may also improve multicore utilisation and, consequently, run-time performance. The thesis presents four algorithms as case studies from the domain of string pattern matching and finite automata. Each case study is conducted in the following manner. The particular sequential algorithm is decomposed into a number of communicating concurrent processes. This decomposition is described in the process algebra CSP. Hoare's CSP was chosen as one of the best known process algebras, for its expressive power, conciseness, and overall simplicity. Once the CSP-based process description has brought ideas to a certain level of maturity, the description is translated into a process-based implementation. The Go programming language was used for the implementation as its concurrency features were inspired by CSP. The performance of the process-based implementation is then compared against its conventional sequential version (also provided in Go). The goal is not to achieve maximal performance, but to compare the run-time performance of an ``ordinary'' programming effort that focussed on a process-based solution over a conventional sequential implementation. Although some implementations did not perform as well as others, some did significantly outperform their sequential counterparts. The thesis thus provides prima facie evidence that a process-based decomposition approach is promising for achieving a better fit between software and current multicore hardware. / Thesis (PhD)--University of Pretoria, 2017. / Computer Science / PhD / Unrestricted

This thesis is based on a study of the development of education through theinnovative use of process-based assessment in technology-rich learningenvironments in teacher and nurse education. The study of process-basedassessment addresses the aim of creating a better understanding of the shiftin emphasis from teaching to learning with regard to theory and practice.The research questions address the use of process-based assessment, andhow the social relationships and issues of content can be understood intechnology-rich learning environments. A methodological approachinvolving design-based research was found to be especially applicable. Thestudy was designed in three iterative didactical design cycles for processbasedassessment in which the first and third cycles were analysed. Theempirical material comprises qualitative semi-structured interviews withteachers and students and questionnaires with students. The empiricalmaterial was analysed through inductive thematic analysis. The theoreticalanalyses in the comprising articles are mainly based on Bernstein’stheoretical framework for studying social relationships through concepts ofsymbolic power and control. For understanding change, with regard to theshift in emphasis from teaching to learning, the analysis is taken to a metalevelby applying Bernstein’s concept of pedagogical device.The results outline the shift in emphasis from teaching to learning fromboth a theoretical and practice perspective. Theoretically, the shift inemphasis from teaching to learning is based upon a shift in symbolic powerand control for teachers. In practice, the shift of symbolic power and controlbetween the teacher, student and content outline considerable overlapsbetween teacher-student, teacher-content and student-content. The overlapshighlight the empirical contribution in this thesis through the concept of“process” that is understood as a negotiation between teacher-student,teacher-content and student-content. The weakening symbolic powerrelationship made a multi-dimensional analysis of the teacher-studentcontentrelationship possible. Theoretically, the shift of symbolic poweroutlines a process of recontextualisation of a new discourse for teaching,learning and assessment. The multi-dimensional analysis highlights thetheoretical contributions to understanding the concept of discourse fromBernstein’s perspective through which the content and context create thediscourse. For practice, process-based assessment frames the notion ofdesigning for the unknown. Designing for the unknown is considered as aframework based upon a set of rules through which teachers and studentsadapt to a problematising approach in teaching, learning and assessment