Because of changing patterns of demand and advances in supporting technologies, distance education is a growing market in the higher education sector. Assuring and maintaining its quality is an important issue for those who deliver it. This requires the development of pedagogical design. The knowledge of how student learn is the basis to develop the theories of teaching. However, distance students' learning activities are invisible to the instructors and researchers, particularly those based in a comprehensive learning environment, such as a University. This has caused difficulties in improving pedagogy in distance education. This study aims to contribute new knowledge to deal with this dilemma: it is limited in scope to postgraduate level and the selected educational field is Built Environment studies. To do this requires a deep understanding of what distance education is, what main theories of pedagogy have been developed and applied, and how students learn within a distance learning environment in the selected field. By answering these questions, the key issues of understanding the distance learning experience can be identified, explored and tested. To achieve these objectives, a mixed methods strategy has been designed. The key elements of the distance learning experience are considered, starting with an instrumental case study and continuing with a questionnaire survey. The case study provided in-depth knowledge on how students learn in the distance learning environment. Based on the case study, it was proposed that metacognition is the key to distance learning success, and an understanding of how students use learning strategy is the way to obtain the required knowledge for pedagogical development in this particular educational field. The outcomes of the case study produced a model of the distance learning experience and further research focused on the issue of learning strategies. A questionnaire survey produced 151 valid responses. The findings include both qualitative and quantitative data in regard to what and how learning strategies were developed by the participants. Through cluster analysis of learning strategies, evaluation of the correlations of relevant learning experience, comparing the means of the main factors, and comprehensive analysis, the outcomes of this thesis provide new knowledge of learning strategies for distance education. In addition, based on the discussions around the purpose and effectiveness of learning strategy, student demands for relevant knowledge and the influences of multiple factors, this thesis argues that developed metacognitive capability can, in fact, be a positive advantage of distance learners over their conventional counterparts, provoking a change in perspective on distance learning and recommendations for pedagogical change.

Standing column wells (SCWs) have the potential to deliver much higher rates of heat transfer to geothermal heating and cooling systems in buildings via heat pumps than conventional vertical borehole heat exchange arrays. Its open-end column design with porous casing along the borehole (depending on the formation) encourages the flow of groundwater from the rock’s porous matrix into the well or the opposite way according to the hydraulic gradients. This approach induces a further heat transfer mechanism in addition to the conduction: it is advection. Advection induced by the groundwater movement due to the hydraulic gradient and the action of the well pump causes warmer water (in winter) and cooler (in summer) to be drawn into the well thus increasing heat transfer capacity. This is beneficial for SCWs to offer much higher heat transfer performance than other conventional approaches. The development of a numerical model for clusters of standing column wells is described in this thesis. The model is three-dimensional, dynamic and solves the governing equations using a finite volume discretisation scheme with a fully implicit algorithm. The slower acting field equations are solved using a wider time interval than that used for the faster acting well equations and the two sets of equations are coupled through the field equation source terms. A groundwater bleed feature is incorporated. The model has been validated thermally and hydraulically using existing field data. Two test cases have been applied to reveal the advantages of using SCWs in UK conditions, competing with the conventional closed-loop system of vertical borehole heat exchangers. The results of the applications suggest that SCWs can deliver substantially higher rates of heat transfer than conventional closed-loop borehole heat exchanger arrays, typically up to 250Wm-1, especially when groundwater bleed is operational. The results also confirm that a bleeding operation can offer up to 2.2K improvement (reduction) in the outlet well water temperature in summer and (increase) in the well water temperature in winter. Investigation results on borehole diameter confirm that a larger well borehole diameter would offer improved heat transfer performance in some cases, according to the relative change of the heat transfer coefficient. Analysis of borehole to borehole spacing seems to suggest that 5m is the most effective spacing of the three different spacing choices for this type of application. The results also show that SCW installation in London Clay performs less well than Magnesian Limestone and Old Red Sandstone; the latter two seem to be appropriate formation types to work with this type of application. The advantage of adopting multiple well arrangements (SCW clusters) over the use of single wells has also been confirmed. The important practical consequence of this is that far less geotechnical drilling is needed as the required borehole depth reduces substantially under multiple well arrangements. The results gathered from three different buildings also reveal that the balance between heating and cooling demands appears to have less impact on the mean formation temperature change than the large cooling application, which is beneficial to maintain a steady system performance over a long period of time. The results also suggest that the impact on the rock formation was very dominant in the first few years but it declined towards the end of the 5 year analysis period used in this work. The results from the CO2 emission analysis demonstrate that an annual carbon emission reduction of up to 46% can be achieved by using the geothermal system with SCWs instead of the conventional system consisting of a gas-fired condensing boiler and a conventional aircooled chiller. They also confirm that the balance between heating and cooling demands has a substantial impact on the carbon saving delivered by this technology.

This work deals with a "passive flow monitoring" technique which can be used to help determine the energy used by a building's heating system. The thesis first highlights the background and importance of energy monitoring in buildings. This work points out that energy monitoring is an important feature in the running of buildings today. In the past, the energy crisis in the 1970's made people aware of how important it was to have knowledge of how buildings consume energy. More recently, environmental issues have reinforced the importance of gaining good quality information on energy use in buildings. This thesis investigates the use of combined port flow characteristics/control signal relationships for three port control valves to predict system water flow rate in heating systems. A laboratory test rig was built and a range of three port valves were tested. A series of combined port flow characteristics/control signal relationships were developed from measurements from the test rig. Curve fit models were then applied to these relationships in the form of polynomial equations. Where practical relationships could not be measured for a valve, a theoretical valve model was derived. In order to validate the polynomial regression model and the mathematical model, the test rig was modified to take into account practical heating system characteristics. A series of flow characteristic results were produced from the modified test rig so that the performance of the two models (empirical and mathematical) could be evaluated. It was found that the empirical model performed well in predicting combined port flow ratios with RMS errors ranging between 2.73% and 6.54%. The mathematical model gave overall prediction errors between -2.63% and +9.25% which compare favourably with the performance of some flow meters. The work then goes on to present an energy use algorithm which incorporates the valve model (empirical or theoretical) for use in BEMS.

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