Reconstructing low-energy housing using ‘systems of practice’.

The residential sector accounts for a third of energy use in the UK (DECC, 2014b) and generates fifteen percent of greenhouse gas emissions (DECC, 2014c). Lowenergy housing is therefore critical to meeting climate change mitigation targets (DECC, 2011). New homes are required to be carbon-neutral by 2016, presenting a considerable challenge to the housing industry (DCLG, 2006). Addressing this ambition remains shaped by the ‘techno-rational paradigm’, where energy savings rely on optimal design, technological diffusion and ‘correct’ use. In contrast, this thesis understands technologies and ‘behaviours’ as connected through social practices, which interrelate in dynamic ‘systems of practice’. Housing policy, newly built homes, and domestic practices are critical to governing low-energy housing transformations, yet initiatives consistently fail to account for inter-connections between these different practices. Whilst interventions are attempted, they frequently go awry, or operate in unexpected ways. Developing a systems of practice analysis, this thesis analyses implementation of the Code for Sustainable Homes (CSH) - a building energy performance standard introduced to drive ‘a step-change in sustainable home building practice’ (DCLG, 2006). A Norfolkbased affordable housing scheme, accredited as carbon-neutral, forms the focus of this mixed-methods case-study. The research identifies that householders incorporate energy-efficient building materials and renewable technologies in ways that frequently fail to mesh with designers’ assumptions. Housing professionals also struggle to modify ingrained ‘ways of doing’. Importantly, these actors and their practices are enabled, or constrained, by connections within and across broader practice systems. This has important governance implications. Research and policy should therefore: (i) conceptually map the housing system delimiting the network of involved actors and agents, and identifying pivotal links for target practices or interventions, (ii) generate multi-actor and multi-pronged interventions and join up distributed sources of evidence, and (iii) attend to how interventions generate reactions, interactions and resistances across the practice system

Thermodynamic Losses in a Gas Spring: Comparison of Experimental and Numerical Results

Reciprocating-piston devices can be used as high-efficiency compressors and/or expanders. With an optimal valve design and by carefully adjusting valve timing, pressure losses during intake and exhaust can be largely reduced. The main loss mechanism in reciprocating devices is then the thermal irreversibility due to the unsteady heat transfer between the compressed/expanded gas and the surrounding cylinder walls. In this paper, pressure, volume and temperature measurements in a piston-cylinder crankshaft driven gas spring are compared to numerical results. The experimental apparatus experiences mass leakage while the CFD code predicts heat transfer in an ideal closed gas spring. Comparison of experimental and numerical results allows one to better understand the loss mechanisms in play. Heat and mass losses in the experiment are decoupled and the system losses are calculated over a range of frequencies. As expected, compression and expansion approach adiabatic processes for higher frequencies, resulting in higher efficiency. The objective of this study is to observe and explain the discrepancies obtained between the computational and experimental results and to propose further steps to improve the analysis of the loss mechanisms

Entrepreneurship Skills: Literature and Policy Review

BIS research paper no. 23

Urinary volatile organic compounds for the detection of prostate cancer

© 2015 Khalid et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The aim of this work was to investigate volatile organic compounds (VOCs) emanating from urine samples to determine whether they can be used to classify samples into those from prostate cancer and non-cancer groups. Participants were men referred for a trans-rectal ultrasound-guided prostate biopsy because of an elevated prostate specific antigen (PSA) level or abnormal findings on digital rectal examination. Urine samples were collected from patients with prostate cancer (n = 59) and cancer-free controls (n = 43), on the day of their biopsy, prior to their procedure. VOCs from the headspace of basified urine samples were extracted using solid-phase micro-extraction and analysed by gas chromatography/mass spectrometry. Classifiers were developed using Random Forest (RF) and Linear Discriminant Analysis (LDA) classification techniques. PSA alone had an accuracy of 62-64% in these samples. A model based on 4 VOCs, 2,6-dimethyl-7-octen-2-ol, pentanal, 3-octanone, and 2-octanone, was marginally more accurate 63-65%. When combined, PSA level and these four VOCs had mean accuracies of 74% and 65%, using RF and LDA, respectively. With repeated double cross-validation, the mean accuracies fell to 71% and 65%, using RF and LDA, respectively. Results from VOC profiling of urine headspace are encouraging and suggest that there are other metabolomic avenues worth exploring which could help improve the stratification of men at risk of prostate cancer. This study also adds to our knowledge on the profile of compounds found in basified urine, from controls and cancer patients, which is useful information for future studies comparing the urine from patients with other disease states

An investigation of heat transfer losses in reciprocating devices

The paper presents a detailed computational-fluid-dynamic study of the thermodynamic losses associated with heat transfer in gas springs. This forms part of an on-going investigation into high-efficiency compression and expansion devices for energy conversion applications. Axisymmetric calculations for simple gas springs with different compression ratios and using different gases are first presented, covering Peclet numbers that range from near-isothermal to near-adiabatic conditions. These show good agreement with experimental data from the literature for pressure variations, wall heat fluxes and the so-called hysteresis loss. The integrity of the results is also supported by comparison with simplified models. In order to mimic the effect of the eddying motions generated by valve flows, non-axisymmetric computations have also been carried out for a gas spring with a grid (or perforated plate) of 30% open area located within the dead space. These show significantly increased hysteresis loss at high Peclet number which may be attributed to the enhanced heat transfer associated with grid-generated motions. Finally, the implications for compressor and expander performance are discussed.This work was supported by the UK Engineering and Physical Sciences Research Council (EPSRC), Grant EP/J006246/1. It was performed using the Darwin Supercomputer of the University of Cambridge High Performance Computing Service, provided by Dell Inc. using Strategic Research Infrastructure Funding from the Higher Education Funding Council for England and funding from the Science and Technology Facilities Council

Urban heritage conservation and rapid urbanization : insights from Surat, India

Currently, heritage is challenged in the Indian city of Surat due to diverse pressures,  including rapid urbanization, increasing housing demand, and socio‐cultural and climate changes.  Where rapid demographic growth of urban areas is happening, heritage is disappearing at an  alarming rate. Despite some efforts from the local government, urban cultural heritage is being  neglected and historic buildings keep being replaced by ordinary concrete buildings at a worryingly  rapid pace. Discussions of challenges and issues of Surat’s urban area is supported by a qualitative  dataset, including in‐depth semi‐structured interviews and focus groups with local policy makers,  planners, and heritage experts, triangulated by observation and a photo‐survey of two historic  areas. Findings from this study reveal a myriad of challenges such as: inadequacy of urban  conservation management policies and processes focused on heritage, absence of skills, training,  and resources amongst decision makers and persistent conflict and competition between heritage  conservation needs and developers’ interests. Furthermore, the values and significance of Surat’s  tangible and intangible heritage is not fully recognized by its citizens and heritage stakeholders. A  crucial opportunity exists for Surat to maximize the potential of heritage and reinforce urban  identity for its present and future generations. Surat’s context is representative of general trends  and conservation challenges and therefore recommendations developed in this study hold the  potential to offer interesting insights to the wider planners and conservationists’ international  community.  This  paper  recommends  thoughtful  integration  of  sustainable  heritage  urban  conservation into local urban development frameworks and the establishment of approaches that  recognize the plurality of heritage values

S-curve characterisation of contractors' cash flow in Nigerian tertiary institutions TETFUND Projects

It was empirically established that 82% of businesses fail due to poor management of cash flow; and that just over half of businesses prepare cash flow projections and compare them with actual figure. The paper established the characteristics of contractors' cash flow handling TETFUND projects in Nigerian Tertiary Institutions with a view to improving financial control in construction using the S-Curve as a tool. The research was exploratory in which cash flow characteristics of three selected projects were established. Project records comprising of project profiles and cash flows were used to generate data for the study. The characteristics of the S-Curves of two of the projects depicted rapid initial start-up indicating engagement of many activities at the beginning, while the third project depicted slow start-up due to unavailability of results of soil test. Subsequently, all the projects recorded average progressions and toward the end, progress of all the projects became slow. All the projects were largely executed under negative net cash flows with one at loss. It is therefore recommended that S-Curve be employed in financial planning and management in executing TETFUND projects in order to project ahead financial commitments and implications required in executing projects. The major limitation of the research was restricted case studies due to confidentiality on financial data.Keywords: Cash Flows, Infrastructural Projects, S-Curve, Tertiary Institutions,TETFUN

Effect of Turbine Upstream Geometry on Pulsating Flow and Turbocharged Si-Engine Performance

The pulsating exhaust flow propagates through the exhaust line upon opening of exhaust valves while carrying a high amount of energy (high pressure and temperature). The amount of energy delivered to the turbine could be affected by turbine upstream geometry along with the propagation. Therefore, in this study, the impact of the turbine upstream geometry (diameter, length of exhaust runner, and exhaust manifold volume) on pulsating flow and engine & turbocharger has been investigated using 1D engine simulation packages, AVL-BOOST. A validated 1-liter 3-cylinder SI-engine model was utilized as a base engine model. The simulation captured how different geometry influences the pulsating pressure profile and the impact on system-level performance and behavior. The current research highlighted that the exhaust manifold volume is strongly associated with exhaust resistance, scavenging, pulsation, knocking, and fuel economy. By minimizing unnecessary volume in the exhaust manifold, it presents high potentials to improve low-speed torque (∼15 %), fuel consumption (∼2.4 %), brake thermal efficiency (∼1.4 %), scavenging and knock resistance against the baseline model.©2023 Springer. This is a post-peer-review, pre-copyedit version of an article published in International Journal of Automotive Technology. The final authenticated version is available online at: https://doi.org/10.1007/s12239-023-0044-3fi=vertaisarvioitu|en=peerReviewed

Three new species, lectotypifications and synonymisations in Millettia (Fabaceae: Faboideae) for Thailand

During preparation of the account of the genus Millettia (Fabaceae: Faboideae) for the Flora of Thailand, some new field collections and specimens from herbaria were found to represent three new species, and here they are described and illustrated with a distribution map. Lectotypes of Millettia names are designated for nine species, five new synonyms of Millettia are proposed and Millettia tecta is raised to species status

Lifestyle and embodied energy: A proposed hybrid analysis method for housing

This thesis set out to form a bridge between the disciplines of architectural history, social and women’s history, building technology and environmental assessment, by investigating changes to existing houses over time and linking these with changes in lifestyle and technology. Abstract The primary aim of this research is to establish a Hybrid Analysis Method for Housing (HAMH) as a vehicle for the investigation of the relationship between the environmental impact of the building materials in a house and the lifestyle of its inhabitants, both immediately after construction and in the present day. The HAMH incorporates both qualitative and quantitative analysis. The former relates to oral interviews with people who lived around the time the case study houses were first constructed, complemented by oral interviews covering the same questions with the present inhabitants of the case study houses. The quantitative part of the research is an investigation of the embodied energy of building materials invested in the case study houses since their construction