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The combined effects of temperature, background noise and lighting on the non-physical task performance of university studentsPronk, Laura January 2008 (has links)
This thesis examines the effects of temperature, background noise and lighting on the mood and performance of university students through laboratory study. These variables are considered in the context of the various building regulations and requirements that educational spaces are subject to. Such results are useful for those involved in the design of educational spaces, acting as an extension to existing standards. A preliminary study was conducted to examine the suitability of using a withinsubjects design, the results of which demonstrate that between-subject methodologies can be more suitable. This finding was used to design a full factorial between-subject methodology. Results showed that noise was the most important variable for mood, with increased sound pressure levels being associated with more negative mood description. Students did not have to find a background noise distressing in order for their mood to be affected by it. Lighting was found have different types of negative effects in both the dim and bright condition, where bright light interfered with language fluency, and dim lighting was associated with concentration errors. Temperature is influential to students' assessment of environment comfort.
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The development, implementation, and application of Demand Side Management and control (DSM+c) algorithm for integrating micro-generation system within built environmentHong, Jun January 2009 (has links)
Recent legislation and building regulations aim to reduce the energy demands of buildings and include renewable and low carbon based micro-generation technologies. Due to the intermittent nature of renewable energy systems and fluctuating demand profiles at the domestic level, matching the demand with a volatile supply of low operating efficiency, as is the case with some low carbon energy systems, at the local level, becomes a big challenge for the widespread implementation of zero/low carbon energy systems. The research undertaken centres on the potential exploitation of demand side resources to provide the solutions to the issues addressed above. This thesis focuses on the development, implementation, and application of a bottom-up Demand Side Management and control (DSM+c) algorithm to create greater flexibility in demand and better facilitate the integration of renewable and low carbon energy technologies within the built environment, without significantly compromising user satisfaction. This DSM+c algorithm can be applied to both strategic and operational levels. The strategic level DSM+c algorithm is suitable for the development and analysis of DSM approaches. The measures of load shifting and demand side control are available to specify the DSM options upon loads. The results, in terms of demand/supply match, energy export/import, and environmental impact etc., before and after having applied DSM+c algorithm upon loads, are quantified when linked with Renewable (RE) & Low Carbon (LC) energy supply systems. The DSM+c algorithm at strategic level has been embedded within a decision support platform, MERIT. MERIT is a demand-supply matching tool for assessing the feasibility of renewable energy systems. This allows engineers to develop appropriate demand supply control strategies. The operational level DSM+c algorithm is capable of controlling loads based on the available supply at a certain time, through the assistance of information gathered from simulation or via real-time measurement. The control impact of the operational level DSM+c algorithm upon internal environmental parameters can be quantified. A virtual platform for implementing the DSM+c algorithm is established, within which the information of demand, supply, and internal environmental parameters, are obtained through simulation and input to carry out the process of the DSM+c algorithm. Furthermore, an Internet-enabled Energy System (IE-ES) platform for implementing these control actions upon individual loads in a practical environment has been developed. Finally two types of case studies are presented respectively, showing how the DSM+c algorithm plays a key role within the whole decision-making procedure in a project and how it is applied to an individual appliance at operational level. The thesis concludes with recommendations of potential applications for this work and prospective further development.
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Earth-air heat exchangers and their potential for low-energy cooling of buildings in the UKAhmed, Abdullahi January 2009 (has links)
There is global effort to reduce the emission of greenhouse gases that causes global climate change, of which significant percentage is related to buildings. Uses of passive and low-energy strategies for indoor thermal environmental control are being explored by researchers to reduce the operational energy consumption in bUildings. One of these options is the use of thermal mass of the ground as a heat source or heat sink for cooling and heating of indoor spaces in bUildings. Earth-air heat exchanger (EAHX) is a subterranean ventilation system that can be used to pre-coollpre-heat building ventilation air supply. Due to the ground's thermal mass, the daily fluctuation of ambient extremes is dampened with increasing depth below the ground surface. Therefore soil temperature at 1 m depth and below is always lower than ambient temperature in summer and higher than ambient temperature in winter. The application of EAHX and knowledge of their performance is scarce under UK climatic and soil conditions. This research therefore aims to evaluate the potential of using EAHX in the UK for cooling buildings in summer. Critical literature review has been undertaken on the performance of EAHX in different climatic conditions and the various approaches to the thermal analysis of EAHX. It reveals that the system has potential for building cooling applications in a variety of conditions. A standalone simulation tool has been developed using the Transient System Simulation Environment (TRNSYS). Building models using different mechanical ventilation strategy have also been developed to enable integrated evaluation of the performance of EAHX on indoor thermal comfort conditions and building cooling loads. Data of climatic and soil parameters required for the thermal analysis of EAHX have been determined for different regions in the UK. Integrated thermal simulations of EAHX system have been conducted using the developed building models and the determined soil and climate conditions. Monitoring data from an existing project incorporating EAHX have been analysed and results have been discussed. Parametric study of EAHX has been carried out for three locations, representing the regional climate span of the UK, in order to evaluate the range of thermal performance of the system. Data of various performance indicators have been established to provide the necessary information for the evaluation of the system potential in different locations. This research has established the thermal performance and the characteristics of the important parameters for the design of EAHX system in the UK. The outcomes are significant in contributing to a better understanding of the system's thermal behaviour and in predicting the thermal performance for building cooling application. As a future work, based upon the data generated by this research, there is a need to develop a full database of the performance data for different configurations of EAHX and at different locations around the country. There is also a need for integrated design tool to evaluate the dynamic thermal performance of EAHX system when integrated with other ventilation strategies.
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A method for evaluating energy-related low-carbon improvement options for urban high density social housingDwyer, Scott Michael January 2009 (has links)
No description available.
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'Towards Sustainable Flooring Systems:An Investigation of Novel Materials' : Towards Sustainable Design and Manufacture ofTextile Flooring ProductsCarter, Diane Tracy January 2007 (has links)
'The EngD research project will be to develop innovative materials andflooring to migrate the textile flooring products towards the company's vision of sustainability. This will involve a holistic consideration ofthe supply chain from sourcing renewable raw materials, improving/re-engineering production processes, refurbishment, recycling, downcycling and disposal. The initial project will be to undertake afeasibility study to investigate the technical/market opportunities open to the company including benchmarking against competitors in the flooring market.' This report describes the preliminary investigation into developing innovative flooring solutions. This project is based at Interface Europe, Shelf Mills, which currently manufactures carpet tiles. Its aim is to move flooring through the next paradigm shift to industrial ecology. The initial part of the project is to examine the industry at present. The early literature review looks at current products in the market place and their perceived benefits and disadvantages. The current manufacturing methods are reviewed in order to fully understand the way in which the industry has developed. The history of Interface Europe is discussed in order to understand the driving force for change within the industry and the changes that are required. The structure of corporate Interface is also discussed in order to understand the author's position and the way in which new products may be bought about and tested.
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The transmission of sound between rooms interconnected by a ventilation ductMackenzie, Robin K. January 1974 (has links)
No description available.
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Quantitative fire risk assessment by combining deterministic fire models with automatic event tree analysisAkashah, Farid Wajdi January 2011 (has links)
Risk assessment is an integral part of the decision making process within the built environment especially with the adoption of performance-based regulations in place of prescriptive-based regulations. This dissertation examines risk assessment methods, identifying problems within the current methods available. Specifically, this dissertation defines gaps in current quantitative risk assessment where there is a need for event tree analysis, a component of quantitative risk assessment, to be improved. The dissertation also examines agent-based modelling and some of its applications across different industries. Agent based modelling has lead to a development of a novel methodology to automate the process of producing event trees for fire risk assessment. The fire risk methodology provides the risk curve for a set of scenarios by developing a software package combining the use of a) deterministic models i.e. fire zone models, b) probabilistic models i.e. Monte Carlo model, and c) an agent-based model including uncertainty analysis. The present fire risk methodology has been applied to two case studies. The first case study involves the application of the methodology to assess the benefit of installing two different options of fire safety systems in a warehouse. The second case study is the application of the methodology to a two-storey dwelling house where its flexibility and its ability to perform uncertainty analysis is further examined. These applications of the methodology to the case studies show the methodology flexibility to be applied within different fire risk assessment domains. Finally, recommendations are made to further develop the methodology to include components such as structural risk assessment module and evacuation assessment module.
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Solar thermal storage using phase change material for space heating in residential buildingsGates, Jonathan Roger January 2009 (has links)
In 2007 the domestic sector was responsible for 27% of all energy consumed by final users in the UK, yet only 1.5% of this energy was met by renewables. The utilisation of renewable energy systems such as active solar water heating with Phase Change Material (PCM) thermal storage, offers vast potential for reducing energy use and CO2 emissions in the domestic energy sector in the UK. Previous research indicated that the incorporation of PCMs in underfloor heating had the potential to make energy savings, but their use in combination with renewable energy had not been explored in the UK. Consequently this was identified as a gap in the current knowledge that the current research would fill. A shortage was also identified in real life performance data on PCM space heating system performance in the UK. The current work successfully addresses this shortfall in data and in doing so provides a significant contribution to knowledge in the area of using solar thermal storage for space heating of residential buildings. An in depth literature review was undertaken as part of the research programme, which identified the key shortcomings in existing PCM based thermal storage systems for space heating. An underfloor space heating system for residential buildings was therefore developed that addresses the weaknesses of the existing systems highlighted in the literature review. The system stores solar thermal energy during the day and then uses this to provide space heating in the evening, thus addressing the problem of matching solar availability to demand. An experimental approach was adopted for the study as numerous researchers (Kauranen et al., 1991, Hasnian, 1998, Kenisarin and Mahkamov, 2007), have demonstrated the unreliability of manufacturer's published thermophysical properties of PCM. Therefore, this research chose to adopt an experimental model approach instead of a mathematical modelling approach. A model consisting of a full size solar collector 4m2 in area and a PCM filled underfloor heating panel was constructed in the laboratory. A methodology was developed to measure the performance of the key modules which allowed the performance of the system to be evaluated. The experimental data indicated that it was possible to use a low flow rate of 2.52 litres per minute, without a detrimental effect on the performance of the PCM panel. The use of a low flow rate minimises parasitic losses and produces significant energy savings in comparison to the use of higher flow rates. The experimental results indicated that the system was able to provide adequate thermal comfort with a maximum floor heat emission of 158 W/m using a flow rate temperature of 50°C. Comparisons of the annual space heating energy of the developed integrated system versus a wet central heating system in the UK revealed a significant reduction of energy use and associated CO2 emissions by as much as 52%.
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Fire safety models for high-rise residential buildings in MalaysiaYatim, Yahya Mohamad January 2009 (has links)
This research investigated the effects of escape route design and specification, and time taken on evacuation process in high-rise residential buildings in Malaysia. The aim is to produce a fire safety model on how fire safety standards in high-rise residential buildings can be achieved by investigating the relationship between human behaviour and structural design, particularly escape route design and specification. In Malaysia, research on fire safety is very new, particularly research on provision of fire safety in high-rise residential buildings. The number of fire cases involved residential buildings is significantly high compared to other building types. Thus, escape routes in high-rise residential buildings should be designed and constructed to enable the occupants to evacuate the building as soon as fire has been detected. Mixed methodologies i.e. quantitative and qualitative methods were adopted in this research. There are three research methods adopted i.e. observation, simulation and questionnaire. Observations were carried out to identify any problems encountered and to develop the study models for further analysis. Investigations of the effects of escape route design and specification on evacuation process were carried out using specialist software, i.e. Simulex, which simulates the evacuation of people from the building. The aim is to study escape route specifications i.e. staircase, fire door and corridor. Questionnaire surveys were than carried out to investigate the occupant’s characteristics, behaviours, perceptions and motivation factors to evacuate the building. From this research, fire safety models proposed for high-rise residential buildings as follows, (1) Fire safety model to achieve fire safety standard in high-rise residential buildings, (2) Escape route designs and specifications, and, (3) Human behaviour model. There are five fire safety components that need to be enhanced i.e. (1) Fire Safety Awareness, (2) Fire Safety Design, (3) Fire Safety Equipments and Evacuation Skill, (4) Fire Safety Audit, and (5) Fire Safety Enforcement. Besides, there are four factors which highly influence the evacuation process, fire and casualty risk i.e.: (1) People behaviour – knowledge and experience, (2) building element and escape routes design, (3) active fire protection system, and (4) legislation and enforcement.
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Artificial hydraulic lime mortar obtained by calcining limestone and siliceous waste materialsZawawi, Rodiah January 2010 (has links)
This study was carried out to produce an artificial hydraulic lime for the repair and conservation of historic masonry. Hydraulic lime mortar is preferred to cement mortar and pure lime mortar for conservation work because it can set and harden in wet condition as well as allowing the old wall to breathe. These characteristics create a repaired mortar which is compatible with natural stone and ancient brickwork, as well as being a more sustainable material. The study focused on the properties of an artificial hydraulic lime mortar obtained by burning a binary mixture of limestone and siliceous waste material. Five raw meals were prepared from five siliceous waste materials obtained as by products from other industrial processes (fly ash, glass cullet powder, silica sand, crushed rock dust, and spent oil shale) with the amount of silica varying between 3 and 16 per cent. The raw meals were burned in an electric furnace at 974oC for 7 hours. The mortar was prepared by mixing hot slaked lime putty (water/lime ratio about 1.6) and ‘Gowrie’ sand at a lime/sand ratio of 1:3 by weight. The limes and lime mortar was prepared and tested according to BS EN 459-2:2001. The investigations carried out on the products are free lime analysis, strength test and microstructure examination. The results show that the most promising hydraulic lime is glass cullet lime, followed by crushed rock lime. The glass cullet lime can be classified as feebly hydraulic. The optimum combination of silica with lime in the glass cullet lime is occurred at 10% silica raw meal. The hydration of silicates in the glass cullet lime mortar of 5% silica raw meal is completed in 28 days of curing. High strength but low lime oxide depletion in the crushed rock lime mortar shows the mortar hardens due to the hydration of silicates and the chemical reaction between silica and slaked lime. The results show that the silica in fly ash, spent oil shale and silica sand requires temperatures higher than 974 degree Celsius to achieve significant reaction with lime. The results suggest that hydraulic lime of appropriate performance can be produced using traditional kiln at low cost. Keywords: artificial hydraulic lime, mortar, siliceous waste, cullet, crushed rock
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