Showing papers by "Cranfield University published in 2002"
TL;DR: The formation, control and recovery of struvite from primarily municipal wastewater and other waste streams are reviewed and treatment options for control and technologies for recovery are discussed.
832 citations
TL;DR: Establishing a general model to describe membrane fouling in such a process is made extremely difficult by the inherent heterogeneity of the biomass matrix, which is highly heterogeneous and includes living microorganisms.
Abstract: Membrane bioreactors (MBRs), in which membranes are applied to biological wastewater treatment for biomass separation, provide many advantages over conventional treatment. However, membrane fouling in MBRs restricts their widespread application because it reduces productivity and increases maintenance and operating costs. Recently much research and development has taken place to investigate, model, and control membrane fouling processes. However, unified and well-structured theories on membrane fouling are not currently available because of the complexity of the biomass matrix, which is highly heterogeneous and includes living microorganisms. Membrane fouling in MBR systems can be reversible (i.e., removable by physical washing) or irreversible (removable by chemical cleaning only), and can take place on the membrane surface or into the membrane pores. Although establishing a general model to describe membrane fouling in such a process is made extremely difficult by the inherent heterogeneity of the syste...
714 citations
TL;DR: The research reported in this paper seeks to address the gap in the literature by presenting data that describes the forces that shape the evolution of the measurement systems used by different organisations.
Abstract: The effectiveness of performance measurement is an issue of growing importance to industrialists and academics alike. Many organisations are investing considerable amounts of resource implementing measures that reflect all dimensions of their performance. Consideration is being given to what should be measured today, but little attention is being paid to the question of what should be measured tomorrow. Measurement systems should be dynamic. They have to be modified as circumstances change. Yet few organisations appear to have systematic processes in place for managing the evolution of their measurement systems and few researchers appear to have explored the question, what shapes the evolution of an organisation’s measurement system? The research reported in this paper seeks to address this gap in the literature by presenting data that describes the forces that shape the evolution of the measurement systems used by different organisations.
590 citations
TL;DR: In this article, the authors describe a scenario where the philosophy of "one size fits all" does not apply to pipeline design, implementation, and control, and the issues underlying the appropriate matching of pipelines to marketplace needs under conditions of demand volatility and price pressure are examined.
Abstract: The issues underlying the appropriate matching of pipelines to marketplace needs under conditions of demand volatility and price pressure are examined. The authors describe a scenario where the philosophy of “one size fits all” does not apply to pipeline design, implementation, and control. Research conducted by the authors and others is used to show how appropriate global supply chain strategies can be developed contingent upon market characteristics and which seek simultaneously to achieve higher levels of customer responsiveness at less total cost to the supply chain as a whole. The selection of the right strategy within a supply chain lends itself to a taxonomic approach. We find that three dimensions (leading to eight possible configurations) are adequate for this purpose. These key dimensions are product characteristics, demand characteristics and replenishment lead-time.
499 citations
TL;DR: A mass balance was conducted at full scale across the whole sewage treatment plant in order to identify a stream to conduct bench-scale struvite crystallisation studies, and the most suitable stream was identified as the centrifuge liquors.
466 citations
TL;DR: The use of near-infrared Raman spectroscopy to interrogate epithelial tissue biochemistry and hence distinguish between normal and abnormal tissues was investigated and principal component fed linear discriminant models demonstrated excellent group separation, when tested by cross-validation.
Abstract: The use of near-infrared Raman spectroscopy to interrogate epithelial tissue biochemistry and hence distinguish between normal and abnormal tissues was investigated. Six different epithelial tissues from the larynx, tonsil, oesophagus, stomach, bladder and prostate were measured. Spectral diagnostic models were constructed using multivariate statistical analysis of the spectra to classify samples of epithelial cancers and pre-cancers. Tissues were selected for clinical significance and to include those which develop into carcinoma from squamous, transitional or columnar epithelial cells. Rigorous histopathological protocols were followed and mixed pathology tissue samples were discarded from the study. Principal component fed linear discriminant models demonstrated excellent group separation, when tested by cross-validation. Larynx samples, with squamous epithelial tissue, were separated into three distinct groups with sensitivities ranging from 86 to 90% and specificities from 87 to 95%. Bladder specimens, containing transitional epithelial tissue, were separated into five distinct groups with sensitivities of between 78 and 98% and specificities between 96 and 99%. Oesophagus tissue can contain both squamous and columnar cell carcinomas. A three group model discriminated the columnar cell pathological groups with sensitivities of 84–97% and specificities of 93–99%, and an eight group model combining both columnar and squamous tissues in the oesophagus was able to discriminate pathologies with sensitivities of 73–100% and specificities of 92–100%. It is likely that any overlap between pathology group predictions will have been due to a combination of the difficulty in histologically distinguishing between pre-cancerous states and the fact that there is no biochemical boundary from one pathological group to the next, i.e. there is believed to be a continuum of progression from the normal to the diseased state. Copyright © 2002 John Wiley & Sons, Ltd.
452 citations
TL;DR: In this paper, the authors investigated the success and failure of performance measurement system design interventions in ten companies and found three important differences between companies that proceeded to implement the measures agreed during the process and those that did not.
Abstract: This paper investigates the success and failure of performance measurement system design interventions in ten companies. In each case, the senior management team was facilitated through a management process to redesign their performance measurement systems. Analysis of the initial pilot case studies suggested three important differences between companies that proceeded to implement the measures agreed during the process and those that did not. Post intervention semi‐structured interviews with the directors and managers directly involved revealed two main perceived drivers of implementation and four perceived factors that block implementation. The results are of specific interest for performance measurement system implementation but have wider implications for our view of management commitment in change management.
447 citations
TL;DR: An assessment of currently available models for predicting concentrations of veterinary medicines entering surface waters indicated that for sulfachloropyridazine, the methods provide reasonable estimates, predicted concentrations being within a factor of two of the maximum measured concentrations.
430 citations
TL;DR: In this paper, the advantages and disadvantages of various thermal barrier coating (TBC) systems are discussed, with the aim of custom designing a TBC system to be both strain tolerant and have a low thermal conductivity.
Abstract: This paper reviews the advantages and disadvantages of various thermal barrier coating (TBC) systems, with the aim of custom designing a TBC system to be both strain tolerant and have a low thermal conductivity. Methods of heat transfer within zirconia based ceramics are discussed, including the influence of coating microstructure and ceramic composition. It is shown the addition of dopant atoms (colouring) is effective in reducing ‘phonon’ transport and that layered microstructures are effective in reducing ‘photon’ transport. Advanced processing, using EB-PVD coating methods has allowed both coloured and layered ceramic coatings to be produced. Measured thermal conductivities of 1.0 W mK −1 have been achieved using these methods, much lower than current commercial EB-PVD coatings at 1.5–1.9 W mK −1 .
412 citations
TL;DR: The simulation of diffuse reflectance spectra of skin is simulated by assuming a wavelength-independent scattering coefficient for the different skin tissues and using the known wavelength dependence of the absorption coefficient of oxy- and deoxyhaemoglobin and water to convert reflected intensity.
Abstract: We have simulated diffuse reflectance spectra of skin by assuming a wavelength-independent scattering coefficient for the different skin tissues and using the known wavelength dependence of the absorption coefficient of oxy- and deoxyhaemoglobin and water. A stochastic Monte Carlo method is used to convert the wavelength-dependent absorption coefficient and wavelength-independent scattering coefficient into reflected intensity. The absorption properties of skin tissues in the visible and near-infrared spectral regions are estimated by taking into account the spatial distribution of blood vessels, water and melanin content within distinct anatomical layers. The geometrical peculiarities of skin histological structure, degree of blood oxygenation and the haematocrit index are also taken into account. We demonstrate that when the model is supplied with reasonable physical and structural parameters of skin, the results of the simulation agree reasonably well with the results of in vivo measurements of skin spectra.
402 citations
TL;DR: An international survey of outsourcing contrasts current practice between US and European companies as discussed by the authors, identifying US companies as pursuing more value adding sourcing strategies while European companies are more focused on gaining economies of scale through outsourcing.
TL;DR: In this article, the authors have shown that small and medium-sized enterprises (SMEs) are rapidly adopting the Internet and e-commerce, however, there is little systematic research into how such companies are adopting.
Abstract: Research has shown that small and medium-sized enterprises (SMEs) are rapidly adopting the Internet and e-commerce. However, there is little systematic research into how such companies are adopting...
TL;DR: In this paper, molecularly imprinted polymers (MIPs) have attracted broad interest from scientists engaged in sensor development, which can be explained by the serious potentia of MIPs.
Abstract: Over the past two decades, molecularly imprinted polymers (MIPs) have attracted broad interest from scientists engaged in sensor development. This attention can be explained by the serious potentia ...
TL;DR: The small, rod-like mineral crystallites changed from a highly anisotropically strained state to one with significantly larger equidimensional crystals possessing little microstrain when heated to > 800 degrees C, discussing in the context of graft bone substitutes and surgical heating of bone.
TL;DR: The first empirical study to examine how the pressures of organizational agility impact upon the workforce is reported on, suggesting that agile workforces acquire the five capabilities of intelligence, competencies, collaboration, culture and information systems (IS).
Abstract: The notion of the agile workforce has been discussed as central to creating the agile organization, which achieves superior environmental responsiveness in contexts of turbulence and change. Previo...
TL;DR: A computational approach for the design of a molecularly imprinted polymer (MIP) specific for Cyanobacterial toxin microcystin-LR is presented, and it is anticipated that the polymer designed could be used in assays, sensors, and solid-phase extraction.
Abstract: A computational approach for the design of a molecularly imprinted polymer (MIP) specific for Cyanobacterial toxin microcystin-LR is presented. By using molecular modeling software, a virtual library of functional monomers was designed and screened against the target toxin, employed as a template. The monomers giving the highest binding energy were selected and used in a simulated annealing (molecular dynamics) process to investigate their interaction with the template. The stoichiometric ratio observed from the simulated annealing study was used in MIP preparation for microcystin-LR. The monomers were copolymerized with a cross-linker in the presence of the template. A control (blank) polymer was prepared under the same conditions but in the absence of template. A competitive assay with microcystin−horseradish peroxidase conjugate was optimized and used to evaluate the affinity and cross-reactivity of the polymer. The performance of the artificial receptor was compared to the performance of monoclonal an...
TL;DR: An overlay material was deposited by the Langmuir-Blodgett technique onto a single-mode optical fiber containing a long-period grating that exhibits characteristic attenuation bands in its transmission spectrum whose central wavelengths were observed to depend on the optical thickness of the overlay material.
Abstract: An overlay material was deposited by the Langmuir–Blodgett technique onto a single-mode optical fiber containing a long-period grating. The long-period grating exhibits characteristic attenuation bands in its transmission spectrum whose central wavelengths were observed to depend on the optical thickness of the overlay material, even for materials that have a refractive index higher than that of silica.
TL;DR: The results suggest that using differences in the volumetric proportions of secondary osteons versus interstitial bone, and the properties of these elements/structures in isolation may be a more accurate method of determining differences in elastic modulus of whole bone between individuals of various ages.
TL;DR: Taking from the viewpoint of clinicians and medical analysts, the potential of Raman spectroscopic techniques as new tools for biomedical applications is discussed and a path is proposed for the clinical implementation of these techniques.
Abstract: Raman spectroscopy has recently been applied ex vivo and in vivo to address various biomedical issues such as the early detection of cancers, monitoring of the effect of various agents on the skin, determination of atherosclerotic plaque composition, and rapid identification of pathogenic microorganisms. This leap in the number of applications and the number of groups active in this field has been facilitated by several technological advancements in lasers, CCD detectors, and fiber-optic probes. However, most of the studies are still at the proof of concept stage. We present a discussion on the status of the field today, as well as the problems and issues that still need to be resolved to bring this technology to hospital settings (i.e., the medical laboratory, surgical suites, or clinics). Taken from the viewpoint of clinicians and medical analysts, the potential of Raman spectroscopic techniques as new tools for biomedical applications is discussed and a path is proposed for the clinical implementation of these techniques.
TL;DR: The cumulative prognostic index allows apportionment of patients with Dukes' B colon cancer into defined prognostic groups, which in turn could allow more objective selection of patients for adjuvant therapy, especially as part of clinical trials.
Abstract: Background and aims: There is a need for objective easily determined pathological prognostic parameters in Dukes9 B colon carcinoma to allow selection of such patients for further treatment as the role of adjuvant chemotherapy for these patients remains unclear. This study was initiated to assess the influence of pathological factors on prognosis in an unselected prospective series of Dukes9 B colonic cancer. Methods: The Gloucester Colorectal Cancer study, established in 1988, recruited more than 1000 cases. Meticulous pathological assessment of the 268 Dukes9 B colonic cancer resections in this series included evaluation of all pathological factors that could influence staging and prognosis. All patients entered a comprehensive follow up system. Results: Four pathologically determined factors—peritoneal involvement, venous spread (both submucosal and extramural), spread to involve a surgical margin, and perforation through the tumour—were independent prognostic factors in multivariate analysis. Combining these four factors into a simple cumulative scoring system generated clinically useful prognostic groups. Conclusions: The cumulative prognostic index allows apportionment of patients with Dukes9 B colon cancer into defined prognostic groups, which in turn could allow more objective selection of patients for adjuvant therapy, especially as part of clinical trials.
TL;DR: In this article, the authors review leadership praxis from the frames of wider spiritualities, link spirituality search with contemporary managerialist practices and survey the breadth of, and commonalities within, varied philosophic positions with regard to the spiritual search.
Abstract: Spirituality is a long‐neglected dimension in the leadership issue as it is in the psychological contract implicit in work organizations. Traditionally rooted in religion, there are wider spiritualities that the organizational actor can draw upon and a burgeoning literature on personal meaning and transformative leadership. This paper reviews leadership praxis from the frames of wider spiritualities, links spirituality search with contemporary managerialist practices and surveys the breadth of, and commonalities within, varied philosophic positions with regard to the spiritual search.
TL;DR: The study found that the use of e-commerce for responding to competitors, providing enhanced customer services and improving relations with suppliers was driving the uptake by smaller businesses to a greater extent than by their larger counterparts.
Abstract: This study compares the reasons why small and large companies are adopting electronic commerce (e-commerce) and compares the benefits realized from the adoption of e-commerce by these two groups of companies. Two surveys that were undertaken contemporaneously on the use of e-commerce by small and large companies in the UK were used as the empirical basis for this study. The study found that the use of e-commerce for responding to competitors, providing enhanced customer services and improving relations with suppliers was driving the uptake by smaller businesses to a greater extent than by their larger counterparts. Only in the area of improved operational efficiency did larger businesses express greater interest in adopting e-commerce. The study also found that smaller businesses believed that they had achieved greater benefits from their e-commerce services than had the larger firms in all areas explored.
TL;DR: In this paper, the authors examine previous literature for indications that gender may be important in explaining differences in impression management behaviors, and report findings from a survey and a qualitative study, showing that gender, especially combined with age and job level, is a differentiating factor in managers' inclinations to use particular IM behaviours.
Abstract: Little attention has been paid to the role which impression management (IM) of genuine and substantial talents and commitment plays in the careers of female and male managers seeking promotion. IM studies have largely investigated the supervisor/subordinate relationship, often with samples of business students in laboratory settings. In the Cranfield Centre for Developing Women Business Leaders, we have focused on the use of IM by practising managers. In this paper, we examine previous literature for indications that gender may be important in explaining differences in IM behaviours. We then report findings from a survey and a qualitative study, showing that gender, especially combined with age and job level, is a differentiating factor in managers' inclinations to use particular IM behaviours. Many women (and some men too) seem uncomfortable with using IM. Women do not always want to play "the organizational game" by the male-constructed unwritten rules, but prefer to trust good management and systems fairness for just rewards. Younger and junior level women managers often recognize that IM may be a useful tool but reject its use for themselves. Women seem to prefer to rely on extra high performance and commitment for visibility to their seniors rather than the networking, ingratiation and self-promotion strategies used more by males. An important consequence is that as ambitious young males use job-focused IM in addition to self and manager-focused strategies, this is likely to leave young women at a considerable disadvantage for promotion, if the strategies are successful.
TL;DR: The data suggest that factors that regulate the distribution of bacteria in the subsoil operate at two scales, in contrast to one scale in the topsoil, and that bacterial patches are larger and more prevalent in theTopsoil.
Abstract: Very little is known about the spatial organization of soil microbes across scales that are relevant both to microbial function and to field-based processes. The spatial distributions of microbes and microbially mediated activity have a high intrinsic variability. This can present problems when trying to quantify the effects of disturbance, management practices, or climate change on soil microbial systems and attendant function. A spatial sampling regime was implemented in an arable field. Cores of undisturbed soil were sampled from a 3 × 3 × 0.9 m volume of soil (topsoil and subsoil) and a biological thin section, in which the in situ distribution of bacteria could be quantified, prepared from each core. Geostatistical analysis was used to quantify the nature of spatial structure from micrometers to meters and spatial point pattern analysis to test for deviations from complete spatial randomness of mapped bacteria. Spatial structure in the topsoil was only found at the microscale (micrometers), whereas evidence for nested scales of spatial structure was found in the subsoil (at the microscale, and at the centimeter to meter scale). Geostatistical ranges of spatial structure at the micro scale were greater in the topsoil and tended to decrease with depth in the subsoil. Evidence for spatial aggregation in bacteria was stronger in the topsoil and also decreased with depth in the subsoil, though extremely high degrees of aggregation were found at very short distances in the deep subsoil. The data suggest that factors that regulate the distribution of bacteria in the subsoil operate at two scales, in contrast to one scale in the topsoil, and that bacterial patches are larger and more prevalent in the topsoil.
01 Aug 2002
TL;DR: Early engine fault diagnosis was carried out based on manufacturer information supplied in a technica... as mentioned in this paper, which has a history almost as long as gas turbine development itself, and has been carried out in the field of diagnostics.
Abstract: Gas turbine diagnostics has a history almost as long as gas turbine development itself. Early engine fault diagnosis was carried out based on manufacturer information supplied in a technica...
TL;DR: Smart overlay coatings as mentioned in this paper are a functionally gradient coating system designed to provide high temperature corrosion protection over a wide range of operating conditions, such as high temperature oxidation and type I hot corrosion.
Abstract: Smart overlay coatings are a functionally gradient coating system designed to provide high temperature corrosion protection over a wide range of operating conditions. The SMARTCOAT design consists of a MCrAlY base, enriched first in chromium, then aluminium to provide a chemically graded structure. At elevated temperatures, above 900°C (1650°F), the coating oxidises to form a protective alumina scale. However, at lower temperatures this alumina scale does not reform rapidly enough to confer protection under type II hot corrosion conditions. The coating is therefore designed with an intermediate chromium-rich interlayer, which permits the rapid formation of chromia healing areas of type II corrosion damage. Laboratory and burner rig tests have been carried out on a series of developmental smart overlay coatings. These have shown that the development of an intermediate chromium-rich phase provides protection under low temperature hot corrosion conditions, while the aluminium-rich surface layer provides resistance to high temperature oxidation and type I hot corrosion. Thus, the single application of SMARTCOAT permits operation over a broad range of industrial and marine turbine conditions.
TL;DR: It is suggested that environmental stress factors, particularly water availability and temperature, and low fungicide doses may stimulate mycotoxin production by Fusaria in vitro and in wheat grain.
Abstract: Fusarium head blight of cereals has, in recent years, become one of the most important pre-harvest diseases worldwide. This paper examines the in vitro efficacy of fungicides to control Fusarium species in cereals and the efficacy in the field on both Fusarium infection of ripening ears as well as their impact on mycotoxin production. Field studies suggest that fungicides such as tebuconazole and metconazole give good control of both Fusarium infection of ears and control of deoxynivalenol (DON) production. However, azoxystrobin and related fungicides are less effective, and grain from treated crops has sometimes been found to have increased concentrations of DON and nivalenol. Studies of isolates of Fusarium culmorum from different parts of Europe showed that complex interactions occur between environmental factors, fungicide type and isolate in relation to growth inhibition and DON production. These studies confirmed the ineffectiveness of azoxystrobin and suggest that environmental stress factors, particularly water availability and temperature, and low fungicide doses may stimulate mycotoxin production by Fusaria in vitro and in wheat grain.
TL;DR: In this paper, the authors locates the position of spirituality in the learning debate and examines the relationship between who we are, our being, with what we do, our doing; and implies that organisational performance can be improved by attending to the spiritual richness of humanity.
Abstract: The growing focus on learning as being key to organisational success has raised the level of debate amongst practitioners and academics alike as to just what learning is Consideration of spiritual ideologies offers the opportunity to reflect upon such areas as: complexity and connectivity, the meaning and purpose of work, individual identity and sensemaking, community and collaborative behaviour, dialogue, moral leadership and wisdom Our spiritual capacity provides a deep foundation from which to explore and question our ontological assumptions This paper locates the position of spirituality in the learning debate; examines the relationship between who we are, our being, with what we do, our doing; and implies that organisational performance can be improved by attendance to the spiritual richness of humanity
TL;DR: In this article, the effect of resin and fiber properties on composite impact, compression after impact (CAI) and mode II energy release rate (GIIC) performance has been studied.
Abstract: The effect of resin and fibre properties on composite impact, compression after impact (CAI) and mode II energy release rate (GIIC) performance has been studied. Impact events were instrumented to record values of Pc, the critical load for initiation of impact damage. Impact response of the laminates was strongly influenced by the fracture toughness of the resin. In contrast, use of high strength and high stiffness fibres did not improve the resistance to impact. The differences in impact and CAI response of the laminates were largely a consequence of the impact damage created at the damage threshold, Pc, rather than of the differences in delamination growth. As a strong correlation was found between GIIC values measured by delamination tests, and those calculated from measurements of Pc, it is suggested that instrumented impact testing may be a more convenient way of determining GIIC in CFRP laminates than delamination tests.
TL;DR: It is found that the OCT imaging resolution is almost reduced exponentially with the increase of the probing depth as opposed to the claimed system resolution, demonstrating that optical clearing could be a useful tool to improve the imaging resolution when the light progressively penetrates the high scattering medium.
Abstract: Multiple scattering is a major source that limits light penetration into biotissues, thereby preventing visualization of the deep microstructures for high-resolution optical imaging techniques. The optical clearing approach is a new adventure in biomedical optics for manipulating the optical properties of tissue; for example, the scattering coefficient and the degree of forward scattering of photons, by the use of the chemical administration method in order to improve the optical imaging depth, particularly for the recently developed optical coherence tomography (OCT). This paper investigates systematically how the multiple scattering affects signal attenuation and localization in general, and how the alterations of optical properties of tissue enhance the optical imaging depth and signal localization in particular, by the use of Monte Carlo simulations through the separate considerations of the least scattered photons (LSP) and multiple scattered photons (MSP). The LSP are those photons that contribute to the precise OCT signal, i.e. localization, and the MSP are those that degrade the OCT signal. It is shown that with either the reduction of the scattering coefficient or the increase of the degree of forward scattering, signal localization and imaging depth for OCT is enhanced. Whilst the increase of the anisotropic factor of the medium is more efficient in improving signal localization, it introduces more scattering events for the photons travelling within the tissue for both the LSP and MSP. It is also found that the OCT imaging resolution is almost reduced exponentially with the increase of the probing depth as opposed to the claimed system resolution. We demonstrate that optical clearing could be a useful tool to improve the imaging resolution when the light progressively penetrates the high scattering medium. Experimental results are also presented to show intuitively how multiple scattering affects OCT signal profiles by the use of intralipid solution and healthy human whole blood, representing moderately and highly scattering media respectively.