Staff publications (SAS)

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  • ItemOpen Access
    Using discrete event simulation to investigate engineering product service strategies
    (2010-09-16) Ball, Peter D.; Alabdulkarim, Abdullah; Cuthbert, Rachel; Thorne, Alan
    As companies develop business models based on service provision through engineering products the role of information becomes increasingly important to achieving high levels of service performance. One approach to achieving higher levels of service performance is to deploy sensing technology in the product to provide the service operation with diagnostic and prognostic information. Simulation modelling techniques are able to capture operational performance of complex systems involving product and information flows and are therefore appropriate to modelling such service provision. This paper documents work carried out in this area and demonstrates the application of simulation when providing a service through engineered products. It would seem logical that receiving increasing product performance information would enable higher levels of service performance to be achieved. The work here shows how performance can be captured and the circumstances in which diagnostic and prognostic information is beneficial as well as when it has little effect.
  • ItemOpen Access
    Enablers and barriers to innovation activities in call centres
    (2009-06-15) Smith, Marisa K.; Ball, Peter D.; van der Meer, Robert
    Call centres have an operating model that aim to reduce costs - this has led to both customers and employees having issues with the current model. This has led to the view that contact centres are not entities in which innovation would occur. This paper identifies the barriers and enablers to innovation activities within call centres and discusses the implications of these to the wider service context.
  • ItemOpen Access
    Simulation of oxy-combustion co-firing coal and biomass with ASU and steam turbine using Aspen Plus
    (International Centre for Sustainable Carbon, 2013-05) Jurado Pontes, Nelia; Gohari Darabkhani, Hamidreza; Oakey, John
  • ItemOpen Access
    Zero carbon manufacturing through process flow modelling
    (2012-10-16) Despeisse, Melanie; Ball, Peter; Evans, Steve; Levers, Andy
    The pressure on natural resources and emerging environmental legislation are leading manufacturers to adopt solutions to reduce their environmental impact, thereby becoming more sustainable, while enhancing competitiveness. Current approaches in this area are fragmented and clustered around technologies rather than around processes that link the technologies together. There is a need to better understand material, energy and waste (MEW) flows, as well as the interaction between processes in a manufacturing facility from a systemic viewpoint. This paper presents an approach using process flow modelling in order to help manufacturers to identify potential improvements to progress towards competitive sustainable manufacturing. Ultimately they could reach zero carbon manufacturing (ZCM) by having zero material resource degradation, zero net energy demand and zero waste across the system.
  • ItemOpen Access
    Resilience to evolving drinking water contamination risks: a human error prevention perspective
    (Elsevier, 2013-06-21) Tang, Yanhong; Wu, Shaomin; Pollard, Simon J. T.; Hrudey, Steve E.
    Human error contributes to one of the major causes of the prevalence of drinking water contamination incidents. It has, however, attracted insufficient attention in the cleaner production management community. This paper analyzes human error appearing in each stage of the gestation of 40 drinking water incidents and their causes, proposes resilience-based mechanisms and tools within three groups: consumers, drinking water companies, and policy regulators. The mechanism analysis involves concepts and ideas from behavioral science, organizational culture, and incentive analysis. Determinants for realizing cleaner drinking water system are identified. Future efforts and direction for embedding resilience into drinking water risk management are suggested. This paper contributes to identifying a framework and determinants of resilience-oriented management mechanisms for cleaner drinking water supply, and, is essential for ensuring the successful practice of managing drinking water contamination risks. It harmonizes the two fields of risk management and resilience thinking, and provides a new insight for implementing effective actions in drinking water-related sectors.
  • ItemOpen Access
    Plausible future scenarios for the UK food and feed system - 2015 and 2030. Report for the UK Food Standards Agency
    (Cranfield University, Institute for Environment, Health, Risk and Futures (IEHRF), 2014-06) Garnett, Kenisha; Delgado, João; Lickorish, Fiona; Medina-Vayá, Ángel; Magan, Naresh; Shaw, Hayley; Rathé, Anna; Chatterton, Julia; Prpich, George; Pollard, Simon; Terry, Leon A
    The report describes the key drivers of the wider environment which informed the development of the scenarios. There are case studies of three representative food types, which illustrate how the scenarios may be used to explore triggers for change in food production and supply in the next 20 years, and what the emerging food safety implications might be under each scenario.
  • ItemOpen Access
    Assessment of land cover change in north eastern Nigeria 1986 to 2005
    (Canadian Center of Science and Education, 2013-11-22) Garba, Samuel; Brewer, Timothy R.
    Environmental disturbance such as drought, overgrazing, and increase in population in north eastern Nigeriaover the years has led to degradation, shortage of land and water resources and sometimes violent conflict amongcommunities. Land cover change provides a vital means of understanding and managing these problems. Thusthis research provided an assessment of how tree, shrub grass, bare ground and urban land cover changed from1986 to 2005. NigeriaSat-1 and Landsat images were used with data obtained from field survey for the landcover classifications. Change in the land covers were analysed according to persistence, swapping, net loss andgain. Uncertainties were analysed by confusion matrices. The overall accuracies of the classifications used forthe analysis are between 60% and 75%. The transition and change accuracies are between 45% and 60%.Approximately 60% of the area of study remained unchanged during the period. Of the remainder,approximately 11% of the area interchanged between shrub grass and bare ground. The most unstable categorywas shrub grass and was also the source of misclassification. The changes in general concurred with theperception of change in the area and gave some insight on the change that occurred.
  • ItemOpen Access
    Renewable energy, landfill gas and EfW: now, next and future
    (C I W M Business Services Ltd, 2010-02) Adu-Gyamfi, K. A.; Villa, Raffaella; Coulon, Frederic
    The United Kingdom (UK) has traditionally used landfill disposal as the predominant method of waste management. However, landfilling is unsustainable due to its harmful effects on the environment and public health. Under the Euorpean Union (EU) landfill directive, member nations are now required to divert biodegradable municipal waste (BMW) from landfills. The UK has also committed to the EU Renewable Energy Directive, which binds it to sourcing at least 15% of its energy mix from renewables by 2020. To meet these targets, the UK has to support alternative waste management options whilst achievingconsiderable deployment of renewables. This research considers the development of energy from waste (EfW) technologies and their potential contribution to UK's renewable energy targets. This study identifies the use of biomethane as road transport fuel and small-scale EfW deployment at community level as applications with huge potential benefits for the UK. These two options are easily Implemetable and could provide substantial savings in greenhouse gas (GHG) emissions. This study concludes that, depending on the pace of investment and availability of suitable feedstock, EfW technologies can contribute up to 50% of UK renewables target by 2020.
  • ItemOpen Access
    Highly linear, compact and cost-effective sensor probes for displacement measurements using range-resolved interferometry
    (EUSPEN, 2021-06-10) Kissinger, Thomas; Wiseman, Kieran B.; Tatam, Ralph P.
    We demonstrate a novel approach for interferometric displacement and vibration sensing using range-resolved interferometry (RRI). The concept exploits the ability of RRI to reject the signal contributions due to multiple reflections that would otherwise lead to high levels of periodic non-linearity errors, allowing the use of very compact and cost-effective sensor heads based on gradient index (GRIN) lenses, with the presented approach thought to be widely applicable across many precision engineering applications.
  • ItemOpen Access
    Controlled porosity alumina structures for ultra-precision hydrostatic journal bearings
    (American Ceramic Society, 2010-11-04) Durazo-Cardenas, Isidro; Stephenson, D. J.; Corbett, John
    A series of fine grade alumina powders has been used in combination with maize starch granules to produce porous structures for porous hydrostatic journal bearing applications. A comprehensive series of tests was conducted to characterize porosity in terms of density, pore size and permeability. Successful processing of quality journal bearing components has been demonstrated for preferred combinations of alumina size and starch content, using fixed processing parameters. The new porous ceramic bearings showed consistent and reproducible properties and are suitable for a wide range of higher precision engineering applications. The porous ceramic bearing processing route has also proved to be low cost and environmentally sound.
  • ItemOpen Access
    Climate change and the changing water cycle: new Indian and UK-India collaborative research initiatives
    (OMICS International, 2012-05-21) Remesan, Renji
    The possible effects of climate change on India’s surface and ground water resources would impart huge pressure on existing water management strategies in coming decades and so. Recent studies shows that the per capita annual water availability in India has considerably reduced from 1820 m3 (2001 statistics) to 1703.6 m3 (2005 statistics) in a limited periods; and this value is very close to the water stress threshold value of 1700 m3 [1]. India is the largest ground water user in world (230 cubic kilometers per year; which is more than quarter of the global total) which covers more than 85% of drinking water supplies and more than 60% of agriculture water are depending on the ground water reserve [2]. As some of the recent studies have highlighted the fact that nearly 29 percent of groundwater blocks in the country fall under the semi-critical, critical, or overexploited categories, the Planning Commission of India has constitute an expert group to identify sustainable management strategies for groundwater use and to provide technical support to enhance outcomes management interventions.
  • ItemOpen Access
    Photochemical growth of silver nanoparticles on c- and c+ domains on PZT thin films
    (American Chemical Society, 2007-06-23) Dunn, Steve; Jones, Paul M.; Gallardo, Diego E.
    The photochemical growth of silver nanoparticles on the negative domains of lead zirconate titanate thin films is reported. A sample of highly [100] orientated lead zirconate titanate, with a ratio of 30:70, that was 65−70 nm thick grown on Pt-coated MgO was poled by use of piezoresponse force microscopy to produce defined regions of surface positive and negative polarization. A comparison between the growth of silver nanoparticles on the surface of the lead zirconate titanate when illuminated with two sources of super band gap UV is given. In both cases the wavelength of illumination leads to growth on the positive domains but only illumination with a Honle H lamp, with a high photon output over 250−200 nm, caused significant growth of silver nanoparticles on the negative domain. The deposition on the negative domain is explained in terms of changed band bending due to the excitation of electrons into the conduction band, the rate of decay to the ground state, and dimensions of the ferroelectric film. The rate of deposition of silver nanoparticles on the negative domains is approximately half that on the positive domains.
  • ItemOpen Access
    Understanding the implications of service contracting in product-service businesses
    (The Operational Research Society, 2012-12) Phumbua, Sarocha; Tjahjono, Benny
    Service contracting has been adopted in several industries especially for high value assets with long life time. Such a contract typically specifies asset usage information, availability or capability of the contracted assets required by customers, and the scope of services the manufacturers are obliged to support the assets. Consequently, such a contract imposes major risks to the manufacturers. This paper aims to explore approaches that be used to assist manufacturers to model service contracts in order to understand the risk and reward prior to committing a contract with customer. The work described in the paper involves the development of a simulation model from a case of the ship building industry. The use of the model in aiding contracting decisions is demonstrated through three experiments conducted at the case company. The outcomes have demonstrated the potential of the approaches in practice and contributed to the Product-Service Systems modelling paradigm.
  • ItemOpen Access
    Biological treatment and thickening with a hollow fibre membrane bioreactor
    (Elsevier Science B.V., Amsterdam., 2014-07-01T00:00:00Z) Zsirai, T.; Wang, Z-Z.; Gabarrón, S.; Connery, K.; Fabiyi, M.; Larrea, A.; Judd, Simon J.
    Aerobic operation of an immersed hollow fibre membrane bioreactor, treating municipal wastewater supplemented with molasses solution, has been studied across mixed liquor suspended solids (MLSS) concentrations between 8 and 32 g L-1, the higher concentrations being normally associated with thickening operations. Only a marginal loss in membrane permeability was noted between 8 and 18 g L-1 when operation was conducted without clogging. The sustainable operational flux attainable above 18 g L-1 was highly dependent upon both the MLSS concentration and the state of the membrane. A temperature-corrected flux of 28 L m-2 h-1 (LMH) was sustained for 18 h at an MLSS of 8 g L-1 using membranes close to initial their virgin-state permeability. This value decreased to around 14 LMH at 20 g L-1 and 5 LMH at 32 g L-1 MLSS for an aged membrane whose permeability had been recovered following clogging. Below the threshold flux operation without significant clogging was possible, such that the membrane permeability could be recovered with a chemically enhanced backflush (CEB). Above this flux clogging took place at a rate of around 7-14 g solids per m2 membrane per m3 permeate volume passed irrespective of the MLSS concentration. The permeability of the unclogged membrane was depressed and could not be recovered using a standard CEB, indicative of irrecoverable pore clogging. The outcomes corroborated previously reported observations concerning the deleterious long-term impacts of clogging, and confirmed the critical importance of operation at a sustainable flux value
  • ItemOpen Access
    Knowledge based environment to support product design validation
    (Elsevier Science B.V., Amsterdam., 2012-02-01T00:00:00Z) Al-Ashaab, Ahmed; Molyneaux, M.; Doultsinou, A.; Brunner, B.; Martínez, E.; Moliner, F.; Santamaría, V.; Tanjore, D.; Ewers, P.; Knight, G.
    A knowledge-based environment to support product design validation of refresh projects (projects with minor changes in comparison with previous ones) has been developed. This was achieved by capturing the relation between the design change of refresh projects with their required physical tests and the historical data of previous projects. The refresh projects constitute the majority, around 60%, of the total number of projects in the collaborating company. The knowledge-based environment framework (Knowledge-Based Environment to Support Product Design Validation - KBE-ProVal) has been implemented on the Product Lifecycle Management Platform, called Teamcenter. The KBE-ProVal development was based on the standardisation of the existing related documents while maintaining the traceability of the decision making process. This implementation will avoid repeating unnecessary and costly physical product tests, thus reducing time and costs for these refresh projects
  • ItemOpen Access
    Towards a harmonisation of the soil map of Africa at the continental scale
    (Elsevier, 2013-12-31T00:00:00Z) Dewitte, Olivier; Jones, Arwyn; Spaargaren, Otto; Breuning-Madsen, Henrik; Brossard, Michel; Dampha, Almami; Deckers, Jozef; Gallali, Tahar; Hallett, Stephen H.; Jones, Robert J. A.; Kilasara, Method; LeRoux, Pieter; Michéli, Erika; Montanarella, Luca; Thiombiano, Lamourdia; van Ranst, Eric; Yemefack, Martin; Zougmore, Robert
    In the context of major global environmental challenges such as food security, climate change, fresh water scarcity and biodiversity loss, the protection and the sustainable management of soil resources in Africa are of paramount importance. To raise the awareness of the general public, stakeholders, policy makers and the science community to the importance of soil in Africa, the Joint Research Centre of the European Commission has produced the Soil Atlas of Africa. To that end, a new harmonised soil map at the continental scale has been produced. The steps of the construction of the new area-class map are presented, the basic information being derived from the Harmonized World Soil Database (HWSD). We show how the original data were updated and modified according to the World Reference Base for Soil Resources classification system. The corrections concerned boundary issues, areas with no information, soil patterns, river and drainage networks, and dynamic features such as sand dunes, water bodies and coastlines. In comparison to the initial map derived from HWSD, the new map represents a correction of 13% of the soil data for the continent. The map is available for downloading.
  • ItemOpen Access
    Improving changeover time: a tailored SMED approach for welding cells
    (Elsevier BV, 2013-06-24T00:00:00Z) Guzmán, Ferradás P; Salonitis, Konstantinos
    Short changeover times have always been critical in manufacturing business. Set-up duration reduction initiatives have been associated with Shingós ‘Single Minute Exchange of Die' (SMED) method. Although a great number of companies have initiated SMED, some failed on implementation. The main reason is that strict application of Shingós SMED methodology is not the most efficient way to reduce set-up times in all situations. In the present study a tailored methodology is presented that has been developed specifically for an automotive supplier. The validation of the proposed method was done through implementation on an industrial welding cell for a period of four months. The main finding is that in addition to SMED tailored methodology, appropriate strategy definition and preparatory activities are key enablers for success. That includes project targets and timescale definition, selection of the appropriate team and coordinator, allocation of specific roles and responsibilities to each team member, training of team and shop floor staff on the new methodology and changeover standards. By implementing the new tailored SMED improvement programme, the company achieved 33% reduction on changeover time.
  • ItemOpen Access
    Establishing an agenda for social studies research in marine renewable energy
    (Elsevier Science B.V., Amsterdam., 2014-02-12T00:00:00Z) Kerr, S.; Watts, L.; Colton, J.; Conway, F.; Hull, A.; Johnson, K.; Jude, Simon R.; Kannen, A.; MacDougall, S.; McLachlan, C.; Potts, T.; Vergunst, J.
    To date, academic research relating to Marine Renewable Energy (MRE) has largely focused on resource assessment, technical viability and environmental impact. Experiences from onshore renewable energy tell us that social acceptability is equally critical to project success. However, the specific nature of the marine environment, patterns of resource distribution and governance means experiences from onshore may not be directly applicable to MRE and the marine environment. This paper sets out an agenda for social studies research linked to MRE, identifying key topics for future research: (i) economic impacts; (ii) wealth distribution and community benefits; (iii) communication and knowledge flow; (iv) consultation processes; (v) dealing with uncertainty; (vi) public attitudes; and (vii) planning processes. This agenda is based on the findings of the first workshop of ISSMER, an international research network of social scientists with interests in marine renewable energy. Importantly, this research agenda has been informed by the experiences of developers, regulators and community groups in Orkney. The Orkney archipelago, off the north coast of Scotland, is home to the most intense cluster of MRE research, development and deployment activity in the world today.
  • ItemOpen Access
    Carbon capture and biogas enhancement by carbon dioxide enrichment of anaerobic digesters treating sewage sludge or food waste
    (Elsevier Science B.V., Amsterdam., 2014-05-01T00:00:00Z) Bajón Fernández, Yadira; Soares, Ana; Villa, Raffaella; Vale, P.; Cartmell, Elise
    The increasing concentration of carbon dioxide (CO2) in the atmosphere and the stringent greenhouse gases (GHG) reduction targets, require the development of CO2 sequestration technologies applicable for the waste and wastewater sector. This study addressed the reduction of CO2 emissions and enhancement of biogas production associated with CO2 enrichment of anaerobic digesters (ADs). The benefits of CO2 enrichment were examined by injecting CO2 at 0, 0.3, 0.6 and 0.9M fractions into batch ADs treating food waste or sewage sludge. Daily specific methane (CH4) production increased 11-16% for food waste and 96-138% for sewage sludge over the first 24h. Potential CO2 reductions of 8-34% for sewage sludge and 3-11% for food waste were estimated. The capacity of ADs to utilise additional CO2 was demonstrated, which could provide a potential solution for onsite sequestration of CO2 streams while enhancing renewable energy production.
  • ItemOpen Access
    On-line measurement of soil properties without direct spectral response in near infrared spectral range
    (Elsevier Science B.V., Amsterdam., 2013-08-01T00:00:00Z) Marin-González, O.; Kuang, Boyan Y.; Quraishi, M. Z.; Munoz-Garcia, M. A.; Mouazen, Abdul Mounem
    So far, the majority of reports on on-line measurement considered soil properties with direct spectral responses in near infrared spectroscopy (NIRS). This work reports on the results of on-line measurement of soil properties with indirect spectral responses, e.g. pH, cation exchange capacity (CEC), exchangeable calcium (Ca-ex) and exchangeable magnesium (Mg-ex) in one field in Bedfordshire in the UK. The on-line sensor consisted of a subsoiler coupled with an AgroSpec mobile, fibre type, visible and near infrared (vis-NIR) spectrophotometer (tec5 Technology for Spectroscopy, Germany), with a measurement range 305-2200 nm to acquire soil spectra in diffuse reflectance mode. General calibration models for the studied soil properties were developed with a partial least squares regression (PLSR) with one-leave-out cross validation, using spectra measured under non-mobile laboratory conditions of 160 soil samples collected from different fields in four farms in Europe, namely, Czech Republic, Denmark, Netherland and UK. A group of 25 samples independent from the calibration set was used as independent validation set. Higher accuracy was obtained for laboratory scanning as compared to on-line scanning of the 25 independent samples. The prediction accuracy for the laboratory and on-line measurements was classified as excellent/very good for pH (RPD = 2.69 and 2.14 and r(2) = 0.86 and 0.78, respectively), and moderately good for CEC (RPD = 1.77 and 1.61 and r(2) = 0.68 and 0.62, respectively) and Mg-ex (RPD = 1.72 and 1.49 and r(2) = 0.66 and 0.67, respectively). For Ca-ex, very good accuracy was calculated for laboratory method (RPD = 2.19 and r(2) = 0.86), as compared to the poor accuracy reported for the on-line method (RPD = 1.30 and r(2) = 0.61). The ability of collecting large number of data points per field area (about 12,800 point per 21 ha) and the simultaneous analysis of several soil properties without direct spectral response in the NIR range at relatively high operational speed and appreciable accuracy, encourage the recommendation of the on-line measurement system for site specific fertilisation