Browsing by Author "Williams, Leon"

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    Advanced visual slam and image segmentation techniques for augmented reality
    (IGI Global, 2022-08-10) Jiang, Yirui; Tran, Trung Hieu; Williams, Leon
    Augmented reality can enhance human perception to experience a virtual-reality intertwined world by computer vision techniques. However, the basic techniques cannot handle complex large-scale scenes, tackle real-time occlusion, and render virtual objects in augmented reality. Therefore, this paper studies potential solutions, such as visual SLAM and image segmentation, that can address these challenges in the augmented reality visualizations. This paper provides a review of advanced visual SLAM and image segmentation techniques for augmented reality. In addition, applications of machine learning techniques for improving augmented reality are presented.
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    An agent-based model for improving museum design to enhance visitor experience.
    (Cranfield University, 2022-11) Ji, Yijing; Tran, Trung Hieu; Simon, Jude; Williams, Leon
    Museum experience is a multi-layered journey including ontological, sensory, intellectual, aesthetic, and social aspects. In recent years, the museum sector has faced a number of challenges in terms of the need to enhance the potential of the experience while maintaining authenticity and credibility. For public science communication in museums, exhibition is an important medium for connecting exhibits and visitors, and as such, the study of visitors' senses and behaviours under impact of various museum layout designs has become an important research direction. The purpose of this study is to explore the recall of visitors' memories in the exhibition space by integrating images, echoes and tactile senses, and then transform memories and interactions into their own experience and knowledge base. The impact of spatial design and other design elements on visitors' memories is also explored. We have conducted Agent-based simulation, by setting up virtual visitors, exhibition spaces and artefact based on real gallery spaces, as a time-saving and cost-saving method to improve exhibition interactivity and content coherence. Meanwhile, through the simulation of this novel way, visitors can observe and predict the interactive experience between visitors and the exhibition, so as to improve the curatorial team's research on tourist behaviour and spatial design scheme. Next, the simulated data on visitors' memory recall behaviour is compared with the actual observed data to explore the authenticity of visitors' behaviour in the simulated museum. The impact of this study is by integrating a variety of shared understandings between curators, exhibition management and participants, drawing on diverse information based on experience, practice and simulation. It seeks to provide future museum- oriented practitioners, particularly in small and medium-sized museum exhibition spaces, with a novel perspective and approach to observing or predicting the experience of visitors' sensory interactions within an exhibition. Furthermore, at the same time as enhancing the visitor’s exhibition experience, the content of exhibition story is fully transformed into its own knowledge accumulation.
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    Aspirational toilet user experiences: translating latent user needs into aspirational user experiences.
    (2018-01) Larsson, Jake; Williams, Leon; Rose, Tim
    What makes a product user experience aspirational? What do people truly want from their products? The aim of this research is to assess the implementation of latent needs to design an innovative aspirational product user experience. The thesis details reflective action-based research on the study of the design of an aspirational toilet user experience; a taboo subject that has little to no aspiration attributed to it. Toilets have not changed in the past 200 years and arguably the user experience is not considered aspirational. The reflections on an admittedly extreme case could in turn have implications for the other practitioners. Latent needs were elicited from 77 households in Kumasi Ghana to understand the motivations for acquiring a toilet while latent needs of the user experience were gathered from hackers online. The results suggest that the negative ‘shut away’ nature of a toilet means people do not attribute value to them while there is a universal fear of the invisibility of disease. The study resulted in the construction of a wellbeing monitoring toilet prototype that would change the meaning people attribute to toilets while beginning to satisfy the fear of disease. A final test was arranged where the improved user experience is shown to be more valuable and aspirational to users by questionnaire because the new concept affords new meaning beyond the utility that toilets currently provide. The reflections on the case study suggest that when implementing latent needs in the design of an aspirational product user experience, it is worth considering that what users say is not what they do and meaning is a dimension of innovation that is as important as technology.
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    Best practice indicators for new product development at universities
    (Cranfield University, 2014-02) Iglesias Bares, Belen; Williams, Leon; Impey, Susan A.
    It is public domain that the development of new products is a crucial activity for business success. Since new product development (NPD) is only conceived as a process within the industry environment, nearly all of the studies on this topic are empirically driven. The most important, and common ones, are based on surveys that look for the habits, methods, and approaches of the best performers, in order to distil NPD best practice. Academics and practitioners generally agree that the environment at small new ventures may differ significantly from the NPD environment at large and medium sized firms. Nevertheless, the advantages attributed to the NPD best practice at large and medium sized companies may also benefit small organisations, including university projects. However, the application of this best practice within university projects needs more exploration. This gap in the knowledge should be investigated since cooperating with external partners a key trend in NPD. Here, the scientist’s expertise and the extensive resources of research universities can make them excellent partners. This study aspires to answer the question “Is new product development at universities performed properly?”. It addresses this debate by carrying out a systematic review, a content analysis, and a benchmarking performance in order to identify six indicators that are associated with higher degree of NPD success in the university environment. Subsequently, empirical data regarding the use of those practices at universities is collected using a questionnaire, then the data is analysed statistically. The results report an alignment of the NPD executed at universities with the NPD best practice indicators. The fulfillment is also compared with industry execution. Finally, the NPD best practice indicators, particularly those that universities perform noticeably better or worse than industry, are discussed. The study provides a tool-questionnaire to organisations interested in assessing outsourced NPD processes (particularly those performed at universities). The results obtained with this tool can be benchmarked with the industry and universities’ data. This study also allows teams engaged in NPDs at universities to determine the weaknesses (i.e. methods and practices that are not usually applied) in this specific environment.
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    Characterisation of blackwater from human transportation systems equipped with vacuum toilets and controlled emissions tanks and its impact on solid/liquid separation technologies
    (Elsevier, 2024-09) Jadhav, N; Brown, T; Williams, Leon; Pidou, Marc
    The first ever detailed characterisation of blackwater from human transportation systems equipped with vacuum toilets and Controlled Emissions Tanks (CET) revealed a stream that is very concentrated in salts and nutrients when compared to other blackwater sources. Escherichia Coli (E. coli) levels in the blackwater characterised were comparatively lower than the range reported for septic tanks, for example. Suspended solids were significantly lower than the levels found in pit latrines, but closely comparable to those reported for gravity toilets. The average COD of 3566 ± 2049 mg/L was typically lower than in pit latrines and gravity flush toilets. These findings then show that the characteristics of the blackwater from human transportation systems are directly impacted by a combination of the low flush vacuum toilets, storage in the CET, and different behaviour for passengers with increased usage for urination over defecation when compared to common uses of toilets. Such factors collectively dictate the nature of the blackwater and require that a solid/liquid separation technology for further processing is fundamentally robust in operation. The greater solids pulverisation, largely resulting from vacuum flushing combined with the storage environment, reduces the suitability of centrifugal and settling technologies whilst making filtration the most suitable option.
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    Conceptual energy and water recovery system for self-sustained nano membrane toilet
    (Energy Conservation and Management, 2016-08-12) Hanak, Dawid P.; Kolios, Athanasios; Onabanjo, Tosin; Wagland, Stuart Thomas; Patchigolla, Kumar; Fidalgo Fernandez, Beatriz; Manovic, Vasilije; McAdam, Ewan J.; Parker, Alison; Williams, Leon; Tyrrell, Sean; Cartmell, Elise
    With about 2.4 billion people worldwide without access to improved sanitation facilities, there is a strong incentive for development of novel sanitation systems to improve the quality of life and reduce mortality. The Nano Membrane Toilet is expected to provide a unique household-scale system that would produce electricity and recover water from human excrement and urine. This study was undertaken to evaluate the performance of the conceptual energy and water recovery system for the Nano Membrane Toilet designed for a household of ten people and to assess its self-sustainability. A process model of the entire system, including the thermochemical conversion island, a Stirling engine and a water recovery system was developed in Aspen Plus®. The energy and water recovery system for the Nano Membrane Toilet was characterised with the specific net power output of 23.1 Wh/kgsettledsolids and water recovery rate of 13.4 dm3/day in the nominal operating mode. Additionally, if no supernatant was processed, the specific net power output was increased to 69.2 Wh/kgsettledsolids. Such household-scale system would deliver the net power output (1.9–5.8 W). This was found to be enough to charge mobile phones or power clock radios, or provide light for the household using low-voltage LED bulbs.
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    Conceptual environmental impact assessment of a novel self-sustained sanitation system incorporating a Quantitative Microbial Risk Assessment approach
    (Elsevier, 2018-05-26) Anastasopoulou, Aikaterini; Kolios, Athanasios; Somorin, Tosin; Sowale, Ayodeji; Jiang, Ying; Fidalgo, Beatriz; Parker, Alison; Williams, Leon; Collins, Matt; McAdam, Ewan; Tyrrel, Sean
    In many developing countries, including South Africa, water scarcity has resulted in poor sanitation practices. The majority of the sanitation infrastructures in those regions fail to meet basic hygienic standards. This along with the lack of proper sewage/wastewater infrastructure creates significant environmental and public health concerns. A self-sustained, waterless “Nano Membrane Toilet” (NMT) design was proposed as a result of the “Reinvent the Toilet Challenge” funded by the Bill and Melinda Gates Foundation. A “cradle-to-grave” life cycle assessment (LCA) approach was adopted to study the use of NMT in comparison with conventional pour flush toilet (PFT) and urine-diverting dry toilet (UDDT). All three scenarios were applied in the context of South Africa. In addition, a Quantitative Microbial Risk Assessment (QMRA) was used to reflect the impact of the pathogen risk on human health. LCA study showed that UDDT had the best environmental performance, followed by NMT and PFT systems for all impact categories investigated including human health, resource and ecosystem. This was mainly due to the environmental credits associated with the use of urine and compost as fertilizers. However, with the incorporation of the pathogen impact into the human health impact category, the NMT had a significant better performance than the PFT and UDDT systems, which exhibited an impact category value 4E + 04 and 4E + 03 times higher, respectively. Sensitivity analysis identified that the use of ash as fertilizer, electricity generation and the reduction of NOx emissions were the key areas that influenced significantly the environmental performance of the NMT system.
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    Contextualising household water consumption patterns in England: a socio-economic and socio-demographic narrative
    (Elsevier, 2023-02-02) Abu-Bakar, Halidu; Williams, Leon; Hallett, Stephen H.
    Water utilities strive to achieve a sustainable reduction in per capita consumption (PCC) by optimising their peak demand management strategies. Socioeconomic (SE) and socio-demographic (SD) characteristics have been proven to correlate with PCC. However, the full extent to which these characteristics underpin peak demand and PCC is yet to be fully understood. Previous work used medium resolution smart meter data from 10,000 households to discover and characterise temporal consumption patterns that underpin peak demand, identifying four distinct clusters of households, namely "Evening Peak" (EP), Late Morning Peak (LM), Early Morning Peak (EM) and Multiple Peak (MP). Using survey results, "Acorn household classification", household occupancy and UK population and household attribute data, this study attempts to draw a correlation between the four clusters and known variables of the participating households. Results have revealed a strong correlation between many endogenous attributes (particularly housing, occupancy, age, number of children and household income) and households' consumption patterns underpinning peak demand. Some 56% of families in privately rented housing show EP characteristics compared with 22% owner-occupiers and 9% social renters. EP households with teenage boys have 37% higher per household consumption (PHC) than average, while EM families with teenage girls use 47% more water in early morning showers than average.
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    Data for the paper "A Straightforward Route to Sensory Device Selection for IoT Systems"
    (Cranfield University, 2018-07-31 11:15) Jones, Paul; Lonne, Quentin; De Almeida Talaia, Pedro; Leighton, Glenn; G. Botte, Gerardine; Mutnuri, Srikanth; Williams, Leon
    Paper abstract: The Internet of Things allows for remote management and monitoring of many aspects of everyday life at the individual and industrial levels. However, designing these systems within constraints of cost and operational context can be a real challenge. The sensor network must be strategically designed, which means selecting the most appropriate sensors to collect a specific measurement in a specific environment and then optimizing their deployment and utilization. To facilitate sensor selection, we propose a straightforward, color-coded, three-sieve selection tool and demonstrate the efficacy of this method through real-life exemplars. The selection tool could be applied to other kinds of technologies, as well.
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    Design and commissioning of a multi-mode prototype for thermochemical conversion of human faeces
    (Elsevier, 2018-03-23) Jurado Pontes, Nelia; Somorin, Tosin; Kolios, Athanasios J.; Wagland, Stuart; Patchigolla, Kumar; Fidalgo, Beatriz; Parker, Alison; McAdam, Ewan; Williams, Leon; Tyrrel, Sean
    This article describes the design and commissioning of a micro-combustor for energy recovery from human faeces, which can operate both in updraft and downdraft modes. Energy recovery from faecal matter via thermochemical conversion has recently been identified as a feasible solution for sanitation problems in low income countries and locations of high income countries where access to sewage infrastructures is difficult or not possible. This technology can be applied to waterless toilets with the additional outcome of generating heat and power that can be used to pre-treat the faeces before their combustion and to ensure that the entire system is self-sustaining. The work presented here is framed within the Nano Membrane Toilet (NMT) project that is being carried out at Cranfield University, as part of the Reinvent the Toilet Challenge of the Bill and Melinda Gates Foundation. For this study, preliminary trials using simulant faeces pellets were first carried out to find out the optimum values for the main operating variables at the scale required by the process, i.e. a fuel flowrate between 0.4 and 1.2 g/min of dry faeces. Parameters such as ignition temperature, residence time, and maximum temperature reached, were determined and used for the final design of the bench-scale combustor prototype. The prototype was successfully commissioned and the first experimental results, using real human faeces, are discussed in the paper.
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    Design Principles for FES Concept Development
    (Cranfield University, 2013-10) Dakin, Samuel; Williams, Leon; Almond, Heather
    A variety of pathologies can cause injury to the spinal cord and hinder movement. A range of equipment is available to help spinal injury sufferers move their affected limbs. One method of rehabilitation is functional electrical stimulation (FES). FES is a technique where small electrical currents are applied to the surface of the user’s legs to stimulate the muscles. Studies have demonstrated the benefits of using this method and it has also been incorporated into a number of devices. The aim of the project was to produce a number of designs for a new device that uses FES technology. The project was completed in conjunction with an industrial partner. A review of the literature and consultation with industrial experts suggested a number of ways current devices could be improved. These included encouraging the user to lean forwards while walking and powering the device using a more ergonomic method. A group of designers were used to produce designs that allowed the user to walk with a more natural gait and avoided cumbersome power packs. The most effective of these designs were combined to form one design that solved both problems. A 3-dimensional model of this design was simulated using computer-aided design software. Groups of engineers, scientists and consumers were also invited to provide input on how a new device should function. Each of these groups provided a design that reflected their specific needs, depending on their experience with similar technology. Low level prototypes were produced of these designs. A group of designers were also used to design concepts for a functional electrical stimulation device based on an introduction given by industry experts. Each of the designs was presented to experienced professionals to obtain feedback. A set of guidelines were also produced during the project that instructed how to create the designs.
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    Developing engineering systems with stakeholder engagement
    (Cranfield University, 2022-05) Chapman, Harris Spencer; Smith, Heather; Williams, Leon
    The activities of the early stages of new product development (NPD) projects have a significant impact on its results. This is evident by the failures of outputs to meet expected levels of adoption being traced back to inadequate elicitation of requirements and validation of the need for the output itself. To address this, the development of consumer goods, software and large-scale construction projects have been shown to benefit from the early involvement of stakeholders in these outputs. However, few studies focus on how this early involvement of stakeholders might advance the development of engineering systems. Although studied in the context of complex products and systems (CoPS), which includes large-scale constructions, engineering systems differ significantly to these and other NPD project outputs. This is due to the absence of end-users, or the general public, being involved as such systems are often automated and hidden within other systems or infrastructure. Adhering to development frameworks prioritising technical maturation furthers this difference, although, like consumer products, a market needs to be addressed. To explore this phenomenon, a single case study of the beginning of a wastewater system NPD project is conducted and supported by studies that identify, engage and evaluate the extent stakeholders can affect its activities. The results support the need for a dedicated early stage for stakeholder engagement. This will help address the implications of findings evidencing problems engineering systems need to address so to achieve expected levels of adoption. Successfully incorporating this new stage whilst prototyping the engineering system itself requires further research. The contributions of this thesis challenge prioritising technical interests during early stages of development, demonstrate the extensive value of analysing qualitative data and support iterative and collaborative NPD approaches. Incorporating these findings will contribute to ensuring highly innovative engineering systems effectively address the needs of their salient stakeholders.
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    Development and prototype testing of a novel small-scale pyrolysis system for the treatment of sanitary sludge
    (Elsevier, 2022-12-31) Beik, Farhad; Williams, Leon; Brown, Tim; Wagland, Stuart T.
    An innovative twin auger pyrolysis reactor for the intermediate conversion of partially wet sanitary faecal sludge generated on train toilets (mobile applications) is designed and successfully commissioned. The effects of operating temperature, feedstock feeding rates and moisture content and their interaction on the distribution and properties of product biofuels with the use of no carrier gas were assessed. Approximate yields of 50 %, 40 % and 10 % were observed for the biooil, syngas and biochar respectively at 500 °C. Meanwhile, the highest calorific value (HHV) of the syngas did not exceed 10 MJ/Nm3. Acidic compounds (10 % RPA) and nitrogen-containing hydrocarbons (18 % RPA) substituted the abundant species in biooil fraction at 500 °C with the lowest feed volumes of feedstock. Biochar presented the highest fixed carbon (58 %) and ash content (37 %) upon higher operating temperatures for the minimum and maximum volumes of feedstock. Interestingly, the retention of inorganics within the structure of char were observed. Meanwhile, the calorific value of the biochar reduced due to intensive reduction reactions at higher temperatures ranging to a minimum of 19 MJ/kg. Effects of reactor design and configuration on the pyrolytic products are discussed accordingly and further implications are provided. Overall, extensive further research for the end-use of pyrolytic products and the investigation of emissions, upon energy recovery or land-application of by-products are suggested.
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    Development of efficient data management and analytics tools for Intelligent sanitation network design.
    (Cranfield University, 2023-05) Jiang, Yirui; Tran, Trung Hieu; Williams, Leon
    According to the World Health Organisation, billions of people lack access to basic sanitation facilities and services, resulting in estimated 2.9 million cases of diseases and 95,000 deaths each year. This is because poor planning, design, maintenance, and access in traditional sanitation networks. Nowadays, intelligent sanitation systems leveraging the Internet of Things (IoT) technology can provide efficient and sustainable services, incorporating sensors, hardware, software, and wireless communication. Furthermore, advanced data analytics tools combined with the intelligent sanitation systems can provide a deeper insight into operations, make informed decisions, and enhance user experience, thereby improving sanitation services. The thesis provides a comprehensive review of literature on intelligent sanitation systems from both academic and industrial perspectives, with the objective of identifying recent advances, research gaps, opportunities, and challenges. Existing solutions for intelligent sanitation are fragmented and immature due to a lack of a unified framework and tool. To address these issues, the thesis introduces a generalised Sanitation-IoT (San-IoT) framework to manage sanitation facilities and a standardised Sanitation-IoT-Data Analytics (San-IoT-DA) tool to analyse sanitation data. The framework and tool can serve as a foundation for future research and development in intelligent sanitation systems. The San-IoT framework can enhance the connectivity, operability, and management of IoT-based sanitation networks. The San-IoT-DA tool is designed to standardise the collection, analysis, and management of sanitation data for providing efficient data processing and improving decision making. The feasibility of the proposed framework and tool was evaluated on a case study of the Cranfield intelligent toilet. The San-IoT framework has the potential to enable system monitoring and control, user health monitoring, user behaviour analysis, improve water usage efficiency, reduce energy consumption, and facilitate decision-making among global stakeholders. The San-IoT-DA tool can detect patterns, identify trends, predict outcomes, and detect anomalies. The thesis offers valuable insights to practitioners, academics, engineers, policymakers, and other stakeholders on leveraging IoT and data analytics to improve the efficiency, accessibility, and sustainability of the sanitation industry.
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    The development of the user interface of an innovative sanitation solution targeted at developing countries
    (Cranfield University, 2014-03) Tierney, Ross; Williams, Leon; Franceys, Richard
    Case Study Impact Statement. Around the World, 2.6 billion people do not have access to a toilet, leading to the deaths of 1.5 million children per year through associated diseases (Kone, 2012). Novel approaches to this problem are needed that utilise the latest research and technology to safely deal with human waste in developing countries. These new sanitation methods have to be carefully developed to meet the needs and aspirations of their target audience. The Bill and Melinda Gates Foundation are seeking to address this with an international competition called the ‘Reinvent the Toilet Challenge’. The winning entries from different universities will employ the latest technology and research to safely deal with the waste and to utilise the potential of the waste. Executive Summary. This thesis will provide academics and new product development (NPD) practitioners with a strategic methodology for a design-thinking based approach to design products for developing countries. This transfer of knowledge will be possible by discussing potential methods before selecting the most appropriate to utilise with the use of a Case Study to give context. The research will commence with a scoping phase to show methods of gaining understanding of the wider problem followed by approaches to down select and synthesise this information into appropriate project requirements. When clear direction has been established, the implementation and development can take place to produce an outcome to meet the project requirements. Suitable validation techniques will be used to ensure the success of the research. The Case Study that will be used is focused on the development of a user interface for a new sanitation system for developing countries. The system is being developed by Cranfield University, as part of the Reinvent the Toilet Challenge funded by the Bill and Melinda Gates Foundation.
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    An empirical test of the influence of rural leadership on the willingness to participate in public affairs from the perspective of leadership identification
    (MDPI, 2023-10-12) Zhang, Mengjuan; Shi, Hongwei; Williams, Leon; Lighterness, Paul; Li, Mingxing; Khan, Asad Ullah
    The participation of villagers in rural public affairs is vital for the sustainable development of rural communities and the improvement of villagers’ quality of life. Various factors, including individual characteristics, village environment, social forces, and national policies, influence villagers’ willingness to participate. However, empirical research on the determinants of villagers’ participation in public affairs often overlooks the role of grassroots leadership. To address this gap, this study proposes a theoretical model examining the relationship between transformational leadership and villagers’ willingness to participate in public affairs. Using a sample of 438 villagers from Jiangsu Province in eastern China, structural equation modeling and regression are employed to analyze the data. The findings indicate that moral modeling, leadership charm, and personalized care directly impact villagers’ willingness to participate in public affairs or indirectly influence it through leadership identification, which acts as a mediator. Furthermore, shared vision enhances the positive relationship between leadership identification and villagers’ awareness of public affairs participation. These findings provide valuable insights for village cadres seeking to promote active participation in public affairs among villagers. Specifically, gaining recognition through virtuous conduct, capabilities, and strong cadre–villager relationships serves as a foundation for influencing villagers’ willingness to participate in public affairs, while shared vision plays a strategic role in mobilizing villagers based on their identification with leaders.
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    An empirical water consumer segmentation and the characterisation of consumption patterns underpinning demand peaks
    (Elsevier, 2021-07-18) Abu-Bakar, Halidu; Williams, Leon; Hallett, Stephen H.
    Characterising individual households’ consumption patterns reliably and ascertaining the extent to which these patterns change and how they underpin aggregate demand continues to present a challenge. This paper presents an empirical characterisation of household water consumption patterns, based on consumer segmentation, to improve the accuracy of demand forecasting and to develop both proactive and responsive water conservation strategies. Medium resolution smart metre data for 2019 for 10,000 households were analysed using Machine Learning (ML), revealing four household clusters whose significant differences are underpinned by a variety of indicators in their temporal consumption patterns. The clusters, labelled according to the predominant peak demand times of constituent households, are ‘Evening Peaks’ (EP), ‘Late Morning’ (LM), ‘Early Morning’ (EM) and ‘Multiple Peaks’ (EP). Some of the significant findings include the fact that on average households in EM only record one peak event in 24 h, compared with the MP clusters’ four peak events, with 2 in every 5 households in MP having a confirmed internal leak compared with 1 in every 5 for the other three clusters. A total of 31,788 Cubic metres (m3) was consumed, constituting a monthly mean of 2,649m3, equating to a per household consumption (PHC) of ~270 litres per household per day (l/h/d). Results also revealed the clusters’ distributed dominance of hourly demand and the most active clusters in different seasons. The paper concludes that identifying the significant differences characterising consumption patterns and their concomitant impact on network demand will not only serve to enhance demand forecasting and the prediction of geographical consumption hotspots but will also allow the delivery of targeted intervention measures according to households’ shared characteristics.
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    Energy recovery from human faeces via gasification: A thermodynamic equilibrium modelling approach
    (Elsevier, 2016-04-01) Onabanjo, Tosin; Patchigolla, Kumar; Wagland, Stuart Thomas; Fidalgo Fernandez, Beatriz; Kolios, Athanasios; McAdam, Ewan J.; Parker, Alison; Williams, Leon; Tyrrel, Sean; Cartmell, Elise
    Non-sewered sanitary systems (NSS) are emerging as one of the solutions to poor sanitation because of the limitations of the conventional flush toilet. These new sanitary systems are expected to safely treat faecal waste and operate without external connections to a sewer, water supply or energy source. The Nano Membrane Toilet (NMT) is a unique domestic-scale sanitary solution currently being developed to treat human waste on-site. This toilet will employ a small-scale gasifier to convert human faeces into products of high energy value. This study investigated the suitability of human faeces as a feedstock for gasification. It quantified the recoverable exergy potential from human faeces and explored the optimal routes for thermal conversion, using a thermodynamic equilibrium model. Fresh human faeces were found to have approximately 70–82 wt.% moisture and 3–6 wt.% ash. Product gas resulting from a typical dry human faeces (0 wt.% moisture) had LHV and exergy values of 17.2 MJ/kg and 24 MJ/kg respectively at optimum equivalence ratio of 0.31, values that are comparable to wood biomass. For suitable conversion of moist faecal samples, near combustion operating conditions are required, if an external energy source is not supplied. This is however at 5% loss in the exergy value of the gas, provided both thermal heat and energy of the gas are recovered. This study shows that the maximum recoverable exergy potential from an average adult moist human faeces can be up to 15 MJ/kg, when the gasifier is operated at optimum equivalence ratio of 0.57, excluding heat losses, distribution or other losses that result from operational activities.
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    Enterprise resource planning system implementation and success measurement : case study of a small to medium sized enterprise
    (Cranfield University, 2014-03) Shaikh, N.; Williams, Leon; Mehnen, Jorn
    It is widely believed that major financial benefits can be achieved by organisations implementing Enterprise Resource Planning software. It is also believed that such systems are a time consuming and a costly endeavour which can result in loss of resource and eventually failure of implementation. Furthermore not all companies have the technical competence or financial stability to take such a risk. Alternatively companies can be more modular in their approach in implementing such solutions, adopting one module at a time: the one that suits them best according to their financial and technical situation and so gradually work towards Enterprise Resource Planning implementation. A measurement technique is also required to track progress, success and failure of such a process. As global trade routes become more affordable and the cost of shipping becomes marginalised compared to the overall cost of a product there is a direct impact on Small to Medium sized enterprises as they start competing with global businesses and not just locally. Enterprise Resource Planning or ERP's are one of the many tools that a company can utilise to enhance its efficiency and become more competitive however implementing such a technology is an expensive and risky undertaking. This thesis aims to outline the systems and technologies that a SME can utilise to achieve such a goal using open-source software infrastructure while reducing the expenses and risk involved. It also points out a more “one step at a time” approach to such implementations, hinting that you implement only what you can afford in terms of time and resource and then build towards a bigger system when time and cash prevails hence having a gradual improvement to the overall ecosystem. The observations derived in this paper are outputs of implementation of such technologies at a local SME acting as the case study. Results show that although such an approach can be helpful in bringing the development cost down, continuous efforts in improving the system and on-going systems support is required for the post-implementation phase to have a positive impact on the performance of the company.
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    An experimental investigation of the combustion performance of human faeces
    (Elsevier, 2016-07-27) Onabanjo, Tosin; Kolios, Athanasios; Patchigolla, Kumar; Wagland, Stuart Thomas; Fidalgo Fernandez, Beatriz; Jurado Pontes, Nelia; Hanak, Dawid P.; Manovic, Vasilije; Parker, Alison; McAdam, Ewan J.; Williams, Leon; Tyrrel, Sean F.; Cartmell, Elise
    Poor sanitation is one of the major hindrances to the global sustainable development goals. The Reinvent the Toilet Challenge of the Bill and Melinda Gates Foundation is set to develop affordable, next-generation sanitary systems that can ensure safe treatment and wide accessibility without compromise on sustainable use of natural resources and the environment. Energy recovery from human excreta is likely to be a cornerstone of future sustainable sanitary systems. Faeces combustion was investigated using a bench-scale downdraft combustor test rig, alongside with wood biomass and simulant faeces. Parameters such as air flow rate, fuel pellet size, bed height, and fuel ignition mode were varied to establish the combustion operating range of the test rig and the optimum conditions for converting the faecal biomass to energy. The experimental results show that the dry human faeces had a higher energy content (∼25 MJ/kg) than wood biomass. At equivalence ratio between 0.86 and 1.12, the combustion temperature and fuel burn rate ranged from 431 to 558 °C and 1.53 to 2.30 g/min respectively. Preliminary results for the simulant faeces show that a minimum combustion bed temperature of 600 ± 10 °C can handle faeces up to 60 wt.% moisture at optimum air-to-fuel ratio. Further investigation is required to establish the appropriate trade-off limits for drying and energy recovery, considering different stool types, moisture content and drying characteristics. This is important for the design and further development of a self-sustained energy conversion and recovery systems for the NMT and similar sanitary solutions.