Recent Submissions

  • The Role of Intangible Human Factors in Business Success in South Asian Ethnic Minority Small Businesses

    Harding, Nancy H.; Williams, Jannine; Cornelius, Nelarine; Wallace, James; Haq, Muhibul (University of BradfordFaculty of Management and Law, 2016)
    Extant scholarship has paid considerable attention to exploring the impact of people-dependent intangible resources on business success but in large organisations only. Research about the role of these resources in small businesses, in general, and in ethnic minority small businesses, in particular, is scarce. The current study attempts to narrow this gap. Since it is impossible to study all the ethnic minority small businesses, this study uses a case study strategy that focuses on South Asian ethnic minority small businesses that deal in fashion. The study adopts a qualitative research methodology, it uses the semi-structured in-depth interview method to collect data, and it espouses an inductive thematic technique for coding/analysis of the data. Five overarching themes emerged from the interview data. These are: business success; compassionate customer service; relationships; knowledge, experience, training and education; and ethnic culture and the wider economic and political environment. Discussion of these themes leads to the formation of the culture-induced entrepreneurship model. According to this model, the continued success of these businesses is driven by the ethnic culture, while the existence of these businesses helps to maintain the culture in return. However, overdependence on the coethnic base might risk the future success of these businesses. This thesis concludes by highlighting its theoretical contributions to the culturalist view and the mixed embeddedness model of ethnic minority entrepreneurship and small business literature. The implications of this study for researchers, practitioners, and policy-makers, as well as its limitations and the possible future research paths, are also discussed.
  • The role of photoreceptors in human skin physiology; potential targets for light-based wound healing treatments. Identification of opsins and cryptochromes and the effect of photobiomodulation on human skin and in cultured primary epidermal keratinocytes and dermal fibroblasts

    Thornton, M. Julie; Botchkarev, Vladimir A.; Castellano-Pellicena, Irene (University of BradfordCentre for Skin Sciences, Faculty of Life Sciences, 2017)
    The positive effect of photobiomodulation in wound healing has previously been reported, however there is a considerable lack of knowledge regarding the molecular mechanisms involved, and no consensus on light parameters. Cytochrome c oxidase (CCO) is established as the main photoreceptor in cells, but light also induces nitric oxide (NO), production of reactive oxygen species (ROS) and activation of ion channels. Emerging new molecular targets include the GPCRs opsins (OPNs) and the circadian clock transcription factors, cryptochromes (CRYs). Localisation of OPN1-SW, OPN3, OPN5, CRY1 and CRY2 was seen in female facial and abdominal human skin. Furthermore, expression of these photoreceptors was retained in primary epidermal keratinocytes and dermal fibroblasts in culture; both cell types expressed OPN1-SW, OPN3, CRY1 and CRY2, at the mRNA and protein level. OPN2 was only expressed in cultured dermal fibroblasts, while in line with in situ expression, OPN5 was only expressed in cultured keratinocytes. The photoreceptor-expressing cultured epidermal keratinocytes demonstrated a dose- and wavelength- dependent response in both metabolic activity and cell migration in a scratch-wound assay. Specifically, low dose (2 J/cm2) blue light (447 nm) increased metabolic activity, but it did not impact keratinocyte migration. In contrast, high dose (30 J/cm2) blue light had no effect on metabolism, but inhibited migration of epidermal keratinocytes. Red light (655 nm) at 30 J/cm2 stimulated metabolic activity but did not modulate migration, while a higher dose of 60 J/cm2 had no effect on keratinocyte metabolic activity. In order to study OPN3 and CRY1 function, they were silenced in keratinocytes using siRNA; additionally 8 μM KL001 was used to stabilize CRY1. KL001 inhibited migration, and induced KRT1 and KRT10, an effect which was abrogated by knockdown of OPN3. Interestingly, knockdown of OPN3 upregulated CRY1 expression, while KL001 upregulated OPN3 expression, indicating a regulation by OPN3 of the molecular epidermal clock. Low levels of blue light increased early differentiation of epidermal keratinocytes, which was mediated by OPN3 and circadian clock mechanisms. However, low levels of blue light decreased keratinocyte DNA synthesis, which was mediated by circadian clock independently of OPN3. Translation of parameters ex vivo showed increasing re-epithelialisation and induction of OPN3 and CRY1 expression following exposure to 2 J/cm2 of blue light; however high doses of blue light inhibited re-epithelialisation. Red light, also increased re-epithelialisation, but had no effect on OPN3 or CRY1 expression. In conclusion, photoreceptors are expressed in human skin and they mediate DNA synthesis, migration and differentiation of epidermal keratinocytes. Furthermore, low dose of blue light interacts with OPN3 to induce epidermal differentiation, through the regulation of the circadian clock. A better understanding of the molecular mechanisms behind the photobiomodulation response in vitro will help to develop light based therapies for human wound healing. Interestingly, selected light parameters translated to human ex vivo skin showed a beneficial effect of low doses of blue (2 J/cm2) and red (30 J/cm2) light in re-epithelialisation.
  • Functional Investigation of Dual αvβ3 and αllbβ3 Integrin Inhibition in Haematological and Solid Tumour Models

    Sheldrake, Helen M.; Patterson, Laurence H.; Elsharif, Amal A.M. (University of BradfordInstitute of Cancer Therapeutics, Faculty of Life Sciences, 2018)
    Invasion and metastasis of cancer is the leading cause of increased mortality. In addition, haematological malignancies (leukaemia and lymphoma) are a significant cause of morbidity and mortality in both children and adults. Therefore, new treatments which will inhibit cancer progression are required. Integrin adhesion receptors, particularly the RGD-binding integrin subfamily comprising αvβ3, αvβ5, αvβ6, αvβ8, αllbβ3, α5β1, α8β1 and αvβ1 are related to progress and spread of cancer and poor prognosis. Because of the importance of integrin biology in the regulation of cancer dissemination, the integrin receptors are being utilised as targets to regulate cancer progression. The goal of this study was to develop a dual αvβ3/ αIIbβ3 expressing model for testing integrin antagonists. Expression of αv, αIIb, and β3 integrin subunits was characterised using immunofluorescence and flow cytometry in a panel of cell lines. After characterising the expression of αv, αIIb and β3 integrin subunits in inducible and natural expression models (K562 and MCF-7 cells respectively), functional tests for cellular adhesion, detachment and migration were determined. Phorbol 12-myristate 13-acetate (PMA)-treated K562 cells showed increased adhesion on fibrinogen compared to untreated cells. Adhesion of cancer cells (K562 ± PMA and MCF-7) to fibrinogen was inhibited and detachment was induced by the known β3 antagonists, cRGDfV and GR104453. Migration of cancer cells (K562 without PMA and MCF-7) was inhibited by combination of the known β3 antagonists. A panel of 12 novel small molecules developed in the ICT was investigated for cytotoxicity and activity in the validated function assays. ICT9055 was the most potent antagonist in inhibition of cell adhesion, migration, and inducing cell detachment. The data presented in this thesis had selected models and assays for evaluating small molecule integrin antagonists and identified ICT9055 as a promising molecule to develop for further preclinical evaluation.
  • Molecular interactions in pharmaceutical preformulation and supramolecular complexes. Structural properties governing drug-plasma protein binding and investigation of amino acids co-crystals

    Paradkar, Anant R.; Liu, Xiangli; Kamble, Sharad R. (University of BradfordSchool of Biomedical Sciences and Pharmacy, Faculty of Life Sciences, 2018)
    The study of pharmaceutical preformulation includes the evaluation of pharmacokinetic, pharmacodynamic and physicochemical properties of the drug molecules that aid the formulation. However, it has a limited role in determining drug dosage optimisation in the formulation. The study of drug-Plasma Protein Binding (PPB), and the lipophilicity, solubility, and ionic behaviours of the desired drug molecules addresses the gap and enhances our undertraining related to the behaviour of the drug molecules in the body. The High-Performance Liquid Chromatography (HPLC) technique was used in the current study to assess drug-PPB interaction. Using Michael Abraham’s ‘Linear Free Energy Relationship’ (LFER) method, two major plasma proteins namely, Human Serum Albumin as HSA and α-1-Acid Glycoprotein as AGP, were used and the structural properties governing drug-plasma protein binding was determined. This is the first time that the effect of ionised species on PPB has been quantitatively evaluated. In addition, the molecular interactions also play a key role in the supramolecular complexes of co-crystals. The project also evaluated the co-crystallisation process and its effect on physicochemical properties of the drug. In the current study, amino acids (AAs) have been observed to be a prominent source of coformers. The AAs showed co-crystals formation with carboxylic acids, nonsteroidal anti-inflammatory drug (NSAID) and citric acid which overcome the hygroscopicity problems and improved the physical stability issues during storage. This study has also identified a new formulation which is helpful for improvement in the stability of effervescent tablets at various relative humidity (RH) conditions which will reduce the manufacturing cost associated with the production of effervescent tablets.
  • Punching shear of concrete flat slabs reinforced with fibre reinforced polymer bars

    Ashour, Ashraf F.; Lam, Dennis; Sheehan, Therese; Al Ajami, Abdulhamid (University of BradfordFaculty of Engineering and Informatics, 2018)
    Fibre reinforcement polymers (FRP) are non-corrodible materials used instead of conventional steel and have been approved to be an effective way to overcome corrosion problems. FRP, in most cases, can have a higher tensile strength, but a lower tensile modulus of elasticity compared to that of conventional steel bars. This study aimed to examine flat slab specimens reinforced with glass fibre reinforced polymer (GFRP) and steel bar materials for punching shear behaviour. Six full-scale two-way slab specimens were constructed and tested under concentric load up to failure. One of the main objectives is to study the effect of reinforcement spacing with the same reinforcement ratio on the punching shear strength. In addition, two other parameters were considered, namely, slab depth, and compressive strength of concrete. The punching shear provisions of two code of practises CSA S806 (Canadian Standards 2012) and JSCE (JSCE et al. 1997) reasonably predicted the load capacity of GFRP reinforced concrete flat slab, whereas, ACI 440 (ACI Committee 440 2015) showed very conservative load capacity prediction. On the other hand, a dynamic explicit solver in nonlinear finite element (FE) modelling is used to analyse a connection of column to concrete flat slabs reinforced with GFRP bars in terms of ultimate punching load. All FE modelling was performed in 3D with the appropriate adoption of element size and mesh. The numerical and experimental results were compared in order to evaluate the developed FE, aiming to predict the behaviour of punching shear in the concrete flat slab. In addition, a parametric study was created to explore the behaviour of GFRP reinforced concrete flat slab with three parameters, namely, concrete strength, shear load perimeter to effective depth ratio, and, flexural reinforcement ratio. It was concluded that the developed models could accurately capture the behaviour of GFRP reinforced concrete flat slabs subjected to a concentrated load. Artificial Neural Networks (ANN) is used in this research to predict punching shear strength, and the results were shown to match more closely with the experimental results. A parametric study was performed to investigate the effects of five parameters on punching shear capacity of GFRP reinforced concrete flat slab. The parametric investigation revealed that the effective depth has the most substantial impact on the load carrying capacity of the punching shear followed by reinforcement ratio, column perimeter, the compressive strength of the concrete, and, the elastic modulus of the reinforcement.
  • Hybrid Modelling and Optimisation of Oil Well Drillstrings

    Bryant, David; Li, Jian-Ping; Rahmanian, Nejat; Alkaragoolee, Mohammed Y.A. (University of BradfordFaculty of Engineering and Informatics, 2018)
    The failure of oil well drillstrings due to torsional and longitudinal stresses caused by stick-slip phenomena during the drilling operation causes great expense to industry. Due to the complicated and harsh drilling environment, modelling of the drillstring becomes an essential requirement in studies. Currently, this is achieved by modelling the drillstring as a torsional lumped model (which ignores the length of the drillstring) for real-time measurement and control. In this thesis, a distributed-lumped model including the effects of drillstring length was developed to represent the drillstring, and was used to simulate stick-slip vibration. The model was developed with increasing levels of detail and the resultant models were validated against typical measured signals from the published literature. The stick-slip model describes the friction model that exists between the cutting tool and the rock. Based on theoretical analysis and mathematical formulation an efficient and adaptable model was created which was then used in the application of a method of species conserving genetic algorithm (SCGA) to optimise the drilling parameters. In conclusion, it was shown that the distributed-lumped model showed improved detail in predicting the transient response and demonstrated the importance of including the drillstring length. Predicting the response of different parameters along the drillstring is now possible and this showed the significant effect of modelling the drillcollar. The model was shown to better represent real system and was therefore far more suited to use with real time measurements.
  • A Mixed Methods Study Investigating the Community Pharmacist’s Role in Palliative Care

    Morgan, Julie; Blenkinsopp, Alison; Miller, Elizabeth J. (University of BradfordSchool of Pharmacy and Medical Sciences, Faculty of Life Sciences, 2017)
    There is little research investigating factors that facilitate or inhibit timely access to palliative care medicines from community pharmacies. Though palliative care is recognised within the UK government’s strategy and community pharmacists are considered to have a role it is uncertain to what extent this aim is incorporated into local practice. This thesis uses mixed methods to investigate the time taken to access palliative care medication from five community pharmacies in one area of England. The effect of prescription errors, stock availability and other factors is examined. Furthermore, semi-structured interviews with five community pharmacists and eleven other healthcare professionals explore medication access and the community pharmacist’s role in palliative care using the Framework method. Stock availability led to delays with one in five customers going to more than one pharmacy to get urgently required palliative care medications. Legal prescription errors were more common on computer generated prescriptions but did not lead to delays. Three subthemes were identified in accessing palliative care medicines: environment and resources; communication and collaboration; skills and knowledge. The community pharmacist’s role in palliative care was limited due to reluctance from other healthcare professionals to share information, poor access to patient records and lack of integration into the primary healthcare team. This study highlights implications for professionals, commissioners and providers to improve services for those trying to access palliative medication. Community pharmacies remain a largely untapped resource for supporting patients, relatives and carers towards the end of life in both cancer and other advanced life-limiting diseases.
  • The Role of Polycomb Repressive Complex 2 in Epidermal Homeostasis and Hair Growth

    Botchkareva, Natalia V.; Mardaryev, Andrei N.; Asamaowei, Inemo E. (University of BradfordFaculty of Life Sciences, 2017)
    Polycomb repressive complex 2 (PRC2) catalyses the methylation of ‘Lys-27’ of histone H3, leading to transcriptional repression of target genes through its catalytic subunit Enhancer of zeste homolog 1/2 (EZH1/2). PRC2 functions as a critical regulator of stem cells in mouse embryonic and adult tissues. However, the role of PRC2 in human skin remains largely unknown. This study investigated the role of PRC2 in human epidermal homeostasis and hair growth. The expression of EZH2 was elevated in differentiating suprabasal layers of the human epidermis. Consistently, EZH1/2 expression and enzymatic activity was upregulated in differentiating primary human keratinocytes (NHEKs) in vitro. Inhibition of EZH2 and Embryonic ectoderm development (EED) in NHEKs stimulated the expression of differentiation-associated genes, therefore leading to their premature differentiation; while inhibition of EZH1/2 reduced cell proliferation and promoted apoptosis. Silencing of EZH2 in NHEKs induced complex changes in gene expression programmes, including the upregulation of terminal differentiation genes, such as Filaggrin. EZH2 expression was downregulated in aged keratinocytes accompanied with upregulation of senescence-associated genes, p16INK4A and p19INK4D, suggesting EZH2 involvement in epidermal aging. In human anagen hair follicle (HF), EZH2 was detected in stem and progenitor cells; and hair matrix keratinocytes. Silencing EZH2 in HFs accelerated anagen-catagen transition and retarded hair growth accompanied by decreased proliferation and increased apoptosis. Silencing EZH2 in outer root sheath keratinocytes resulted in upregulation of p14ARF and K15, suggesting EZH2 involvement in regulating proliferation and stem cell activity. Thus, this study demonstrates that PRC2-mediated repression is crucial for epidermal homeostasis and hair growth. Modulating the activities of PRC2 in skin might offer a new therapeutic approach for disorders of epidermal differentiation and hair growth.
  • An examination into the quality of regional trade institutions: The economic community of West African states (ECOWAS); a historical, theoretical and modelling perspective

    Jackson, Karen; Potts, David J.; Bah, Essa (University of BradfordDivision of Economics, Faculty of Social Science, 2017)
    This thesis examines the determinants of institutional quality and the process of convergence in the ECOWAS in order to inform policy about the region’s deep integration scheme. The first part of the thesis examines the historical changes that took place in the development of common institutions in West Africa in the pre-independence era. The findings demonstrated that the region exhibited some common institutions, including common currencies, standardised trade rules and protection of trade routes which facilitated regional and international trade. A single administration system helped in the effective implementation of the common institutions. Therefore, historical changes after independence led to the loss of some facets of these common institutions in West Africa. The second part examined determinants of institutional quality and the process of convergence using econometric analysis. The findings demonstrated that the process of convergence could be accelerated if WAMZ and WAEMU work together as one monetary zone under ECOWAS. Moreover, the findings also demonstrated that the level of development, state capacity, FDI, regional trade, history and regional trade partners institutional quality contain useful information in explaining the quality of institutions today. Therefore, ECOWAS’s deep integration goal would require improving some of these factors in order to facilitate the process of developing common institutions and improve their quality. In the long term, a single administration system akin to the colonial era and the Empires of Western Sudan would be desirable. This will require political commitment to do so. ECOWAS members should have the confidence that deep integration is feasible given that it existed in the region in the past.
  • The Impact of Oil Revenue on the Iranian Economy

    Jalilian, Hossein; Morvaridi, Behrooz; Olfati, Ronak (University of BradfordFaculty of Social Sciences, 2018)
    This study aims to identify the effects of oil income on economic growth in Iran over the period 1955-2014. The empirical literature indicates that countries with natural resources are growing more slowly than their counterparts. However, the results from this literature are far from conclusive, particularly in regard to the role played by oil-rich countries. Needless to say, this role depends on other factors as well, including the political situation in the country, the quality of institutions, and the efficacy of the financial system. Some empirical research has found that natural resources, particularly oil, can have a positive impact on the output of a country. although natural resources are not a factor of production in growth theories, studies have used different growth frameworks in order to discover whether having natural resources is a blessing or a curse. In line with recent studies, this work uses an augmented neoclassical growth model to develop a theoretical framework where oil enters the long-term output of the country through saving and investment. Overall, the results suggests that oil income has a positive impact on the level of output per capita in Iran. The findings of the econometric results are in line with the historical analysis of the study. Since different methods and proxies were used, a total of eight models were estimated. Interestingly, when PRIVY is used as an index of financial development, the result of the study changes and oil no longer has a significant impact on the economy. However, this can be translated to an inefficient allocation of credit to the private sector.
  • The Isolation of Human Rod and Cone Photoreceptor Activity combining Electroretinography and Silent Substitution Techniques

    McKeefry, Declan J.; Gilchrist, James M.; Maguire, John C. (University of BradfordDepartment of Optometry and Vision Science, 2017)
    Aims: The electroretinogram (ERG) can be used to independently assess the function of rod and cone photoreceptors within the human retina. The work in this thesis sought to investigate an alternative method of recording the ERG, using the silent substitution paradigm (Estevez and Spekreijse 1982). The aims are separated into two parts, firstly, the isolation and characterisation of the non-dark adapted rod photoreceptor response, and secondly, characterising the ERG response from L-, M- and S-cones. Methods: Rod, L-, M- and S-cone isolating as well as non-isolating sinusoidal flicker and transient square-wave stimuli were generated on a 4 primary LED ganzfeld stimulator to elicit ERGs from non-dark adapted participants with normal and compromised rod or cone function. Results: The results from the rod experiments showed that ERGs elicited by rod isolating silent substitution stimuli exhibit low-pass temporal frequency response characteristics with an upper response limit of 30Hz and saturate beyond 1000ph Td. Responses are optimal between 5 – 8 Hz and between 10-100 photopic Td. There is a significant correlation between the response amplitudes obtained with the silent substitution method and current standard clinical protocols. The results from the cone experiments showed that the L-, M- and S-cone stimulation produced ERGs with very different morphologies. L- and M-cone stimulation is of limited use as an objective measure of colour vision deficiency. Conclusion: Silent substitution provides an effective method for the isolation of human rod and cone photoreceptor function in subjects when stimuli are used within appropriate parameter ranges.
  • Young British Muslims in Higher Education: exploring the experiences and identities of Bradford students within a narrative framework

    Johnson, Sally E.; Alam, M. Yunis; Hussain, Ifsa (University of BradfordFaculty of Social Sciences, 2016)
    This research aims to explore the lived experiences of young British Muslims in higher education at the University of Bradford and the implications this has for the construction of their identities. The increased participation of Muslims in higher education has been hailed a major success story and is said to have enabled the forging of new, alternative, more empowering identities in comparison to previous generations. This thesis provides a new approach in exploring young British Muslims identity by focusing on the dynamics underling identity construction through the use of a pluralistic method to present an array of informants’ accounts of their experiences (Frost et al., 2011). Phase one of the research included qualitative ethnographic observations which were carried out at the University of Bradford City Campus and was chosen in order to capture the use of the various social settings by informants and to understand actions, practices and meanings people gave to issues relevant to the research. Moreover, phase one was used to identify diversity of experience and select participants for phase two, the more focused aspect of the study which involved narrative interviews. A generative narrative interview was conducted with five young Muslims and aimed to understand how students negotiated their identity as Muslims in Britain within the higher educational contexts. The research revealed that rather than Muslims utilising university as a place whereby they are able to forge new identities, as depicted in previous literature, higher education is a context which demands the negotiation of identities that both enabled and constrained.
  • Sanitation Realities in Peri-Urban Communities: Unfreedoms, Capabilities and the Conscious Mind - A Case of Chennai, India

    Anand, Prathivadi B.; Morvaridi, Behrooz; Immler, Ulrike S-HE (University of BradfordFaculty of Social Sciences, 2018)
    This thesis assesses sanitation realities experienced by peri-urban slum dwellers in Chennai, India, to investigate whether rapid economic growth translates into pervasive safe sanitation, otherwise a threat to human security. This is in line with the Sustainable Development Goals of ‘leaving no one behind’. The empirical methodology consists of qualitative comparative case studies approached through rapid appraisal. At least 5 interviews at each of the 10 different slum settlement locations within the Chennai Metropolitan area were conducted. Both the locations and the settlers were conveniently sampled. The settlements were chosen as they mostly lay in a rapidly urbanizing area. The selection of interviewee was determined by availability, yet leaning towards women who are more vulnerable when lacking safe sanitation facilities, and who are the primary caregivers in the household. The research found that out of the 10 settlements visited, 5 habitually practiced open defecation, as no sanitation facilities were available. Hence some settlers were restricted in their freedom to be safe from emotional or physical harm: threatened by dangerous pathogens released into the environment, and insecurities due to lack of privacy. Conceptually the thesis applies an understanding of how affecting influences in individual history and living environment impact upon an individual’s conscious mind, connecting the capability approach to consciousness research. The thesis argues how settlers, overlooked by public services, and subjected to the dangerous and humiliating practice of open defecation, are faced with mental health issues and a diminished likelihood to productively engage, and exercise agency for human growth.
  • Parameters of managerial effectiveness and development of third sector managers. An empirical study of HIV NGO managers in India

    Analoui, Farhad; Kazi, Shehnaz (University of BradfordPeace Studies and International Development, 2017)
    This unique and first-time research explores the parameters of effectiveness among HIV/AIDS and development NGO managers in India. The aim of this research has been investigate and explore how these managers perceive and view their own effectiveness at work. This research contextualises Analoui's Model (1999, 2002) of eight parameters of managerial effectiveness and three contextual factors, which explores and identifies the inter-relationship between the factors and causal influences which form the basis for their increased effectiveness. The methodology employed include qualitative semi-structured individual interviews with 16 NGOs managers and 2 focus-group interviews with 16 non-managerial staff. The results revealed a myriad of factors and influences concerning the NGO managers’ perception, managerial skills and competencies, organizations criteria for effectiveness, opportunities, demands and constraints involved, as well as the inter-organisational relationship and the dominant managerial philosophy of effectiveness. All the parameters of effectiveness and contextual factors of the Model (1999, 2002) apply and are suitable for this context, however, based on the main findings and in-depth discussions, the model has been adapted and modified in order to fit this unique and complex, highly diverse, holistic, multi-faceted and culturally specific context. The findings also indicate to numerous inter-linked factors both internally and externally of the NGOs and, include various training and development (T&D) needs for managers, with implications for the formation of adequate policies and implementation of relevant development programmes to improve and increase NGO managers effectiveness in India.
  • Adaptive Coded Modulation Classification and Spectrum Sensing for Cognitive Radio Systems. Adaptive Coded Modulation Techniques for Cognitive Radio Using Kalman Filter and Interacting Multiple Model Methods

    Sheriff, Ray E.; Al-Araji, S.R.; Hu, Yim Fun; Al-Juboori, Ahmed O.A.S. (University of BradfordFaculty of Engineering and Informatics, 2018)
    The current and future trends of modern wireless communication systems place heavy demands on fast data transmissions in order to satisfy end users’ requirements anytime, anywhere. Such demands are obvious in recent applications such as smart phones, long term evolution (LTE), 4 & 5 Generations (4G & 5G), and worldwide interoperability for microwave access (WiMAX) platforms, where robust coding and modulations are essential especially in streaming on-line video material, social media and gaming. This eventually resulted in extreme exhaustion imposed on the frequency spectrum as a rare natural resource due to stagnation in current spectrum management policies. Since its advent in the late 1990s, cognitive radio (CR) has been conceived as an enabling technology aiming at the efficient utilisation of frequency spectrum that can lead to potential direct spectrum access (DSA) management. This is mainly attributed to its internal capabilities inherited from the concept of software defined radio (SDR) to sniff its surroundings, learn and adapt its operational parameters accordingly. CR systems (CRs) may commonly comprise one or all of the following core engines that characterise their architectures; namely, adaptive coded modulation (ACM), automatic modulation classification (AMC) and spectrum sensing (SS). Motivated by the above challenges, this programme of research is primarily aimed at the design and development of new paradigms to help improve the adaptability of CRs and thereby achieve the desirable signal processing tasks at the physical layer of the above core engines. Approximate modelling of Rayleigh and finite state Markov channels (FSMC) with a new concept borrowed from econometric studies have been approached. Then insightful channel estimation by using Kalman filter (KF) augmented with interacting multiple model (IMM) has been examined for the purpose of robust adaptability, which is applied for the first time in wireless communication systems. Such new IMM-KF combination has been facilitated in the feedback channel between wireless transmitter and receiver to adjust the transmitted power, by using a water-filling (WF) technique, and constellation pattern and rate in the ACM algorithm. The AMC has also benefited from such IMM-KF integration to boost the performance against conventional parametric estimation methods such as maximum likelihood estimate (MLE) for channel interrogation and the estimated parameters of both inserted into the ML classification algorithm. Expectation-maximisation (EM) has been applied to examine unknown transmitted modulation sequences and channel parameters in tandem. Finally, the non-parametric multitaper method (MTM) has been thoroughly examined for spectrum estimation (SE) and SS, by relying on Neyman-Pearson (NP) detection principle for hypothesis test, to allow licensed primary users (PUs) to coexist with opportunistic unlicensed secondary users (SUs) in the same frequency bands of interest without harmful effects. The performance of the above newly suggested paradigms have been simulated and assessed under various transmission settings and revealed substantial improvements.
  • Development of National Drug Policy in the State of Kuwait

    Clark, Brian J.; Alali, Khaled Y.A.A (University of BradfordFaculty of Life Sciences, 2016)
    This Thesis examines the benefits and usefulness of a National Drug Policy (NDP) for the developing of the Health Care System in Kuwait. The NDP is one of the most important structures of the Health System which can lead to improved health services by establishing guidelines, proposals and directives to organize, structure and regulate health legislation; it is of help to ensure the availability of quality, safety and efficacy in using medicines and it can reduce the irrational use of medicines. The NDP is a frame work between the government, schools and universities, media, health professionals, pharmaceutical industries and companies and public. It is cooperation between the public and private sectors to achieve the goal of access to good quality medicines for all. However there are many key factors which need to be examined before the National Drug Policy is introduced and these are considered the baseline for establishing a good policy, and includes; selection of essential drugs, affordability of drugs, drug financing, supply management, drug regulation, rational use of drugs, drugs registration, purchasing of drugs, health research and human resource development. During this research study from 2012 – 2015 several visits to the public and private health areas, were undertaken. At this time there were discussions with 121 health professionals and data was collected and this indicated that in Kuwait there are no such policies. This is despite the availability of financial means, specialized human resources and the existence of the ministerial decisions and regulations governing the health sector in both public and private, whether hospitals, health centers, pharmacies and health departments. In addition it is suggested that the process of a good NDP should be built around 3 main components which includes: 1.Development, 2. Implementation and 3. Monitoring and Evaluation. Therefore the establishing of a NDP without implementation and monitoring is not enough and does not achieve the desired results. The aim of this Thesis is to establish a NDP in the State of Kuwait. This policy is necessary for the State of Kuwait to ensure development an improvement of the Health Care System and ensure better health for population.
  • The Development of a Knowledge-Based Wax Deposition, Three Yield Stresses Model and Failure Mechanisms for Re-starting Petroleum Field Pipelines. Building on Chang and Boger’s Yield Stresses Model, Bidmus and Mehrotra’s Wax Deposition and Lee et al.’s Adhesive-Cohesive Failure Concepts to better Underpin Restart Operation of Waxy Crude Oil Pipelines

    Benkreira, Hadj; Fakroun, Abubaker A. (University of BradfordFaculty of Engineering and Informatics, 2017)
    Twenty years ago, Chang et al. (1998) introduced the three-yield stresses concept (dynamic, static and elastic limits) to describe yielding of waxy crude oils cooled below the wax appearance temperature (WAT). At the time, the limits in rheological instruments were such that they never actually measured the elastic-limit, a key fundamental property. Using modern instruments, this research succeeds in recording for the first time the entire yielding process down to stresses of 10-7 Pa and shear rate of 10-6 min-1 as a function of temperature, cooling rate and stress loading rate using two waxy oils of different origins and wax content. A four-yield stress model is established using derivative data (dynamic fluidity and failure acceleration). In addition, calorimetry (DSC) and microscopy (CPM) helped extract WAT, the gel and pour points and link gel crystal structure and its yielding and breakage to rheological properties. The yielding stresses measured rheologically were tested in laboratory pipelines at two diameter scales, 6.5mm and 13.5mm to compare stresses in uniform and non-uniform cooling. It is demonstrated that rheological instruments can only predict gel breaking pressure when the cooling rate is low, i.e. yielding at the pipe wall. A complementary heat transfer study was performed on a section of pipe statically cooled, both experimentally and theoretically to predict the gel front-liquid oil interface that develops in industrial pipeline where gel breaking occurs. This key information together with rheological data provide the means to predict accurately restart pressures of shut gelled pipelines that have eluded previous research.
  • Performance Modelling and Analysis of a New CoMP-based Handover Scheme for Next Generation Wireless Networks. Performance Modelling and Analysis for the Design and Development of a New Handover Scheme for Cell Edge Users in Next Generation Wireless Networks (NGWNs) Based on the Coordinated Multi-Point (CoMP) Joint Transmission (JT) Technique

    Kouvatsos, Demetres D.; Ahmed, Rana R. (University of BradfordFaculty of Engineering and Informatics, School of Electrical Engineering and Computer Science, 2017)
    Inter-Cell Interference (ICI) will be one of main problems for degrading the performance of future wireless networks at cell edge. This adverse situation will become worst in the presence of dense deployment of micro and macro cells. In this context, the Coordinated Multi-Point (CoMP) technique was introduced to mitigate ICI in Next Generation Wireless Networks (NGWN) and increase their network performance at cell edge. Even though the CoMP technique provides satisfactory solutions of various problems at cell edge, nevertheless existing CoMP handover schemes do not prevent unnecessary handover initialisation decisions and never discuss the drawbacks of CoMP handover technique such as excessive feedback and resource sharing among UEs. In this research, new CoMP-based handover schemes are proposed in order to minimise unnecessary handover decisions at cell edge and determine solution of drawbacks of CoMP technique in conjunction with signal measurements such as Reference Signal Received Power (RSRP) and Received Signal Received Quality (RSRQ). A combination of calculations of RSRP and RSRQ facilitate a credible decision making process of CoMP mode and handover mode at cell edge. Typical numerical experiments indicate that by triggering the CoMP mode along with solutions of drawbacks, the overall network performance is constantly increase as the number of unnecessary handovers is progressively reduced.
  • More than bones. An investigation of life, death and diet in later prehistoric Slovenia and Croatia

    Armit, Ian; Koon, Hannah E.C.; Buckberry, Jo; Nicholls, Rebecca A. (University of BradfordFaculty of Life Sciences, School of Archaeological and Forensic Science, 2017)
    The East Alpine region formed an important crossroads in later prehistoric Europe, through which ideas, people and objects flowed. This was particularly the case during the Late Bronze Age/ Early Iron Age, when an increasingly competitive society was evolving, with the formation of more complex social structures and the rise of ‘elites’. This has been evidenced in a shift in burial customs, from Urnfield-type cremation burial to the construction of tumuli and the adoption of elaborate inhumation burial. This multidisciplinary, multi-scalar approach to the analysis of human remains aims to explore the evolving structure, homogeneity and heterogeneity of communities inhabiting central and eastern Slovenia, and north-eastern Croatia, during the Late Bronze Age and Early Iron Age. The application of multiple methods, including the osteological analysis of cremated and non-cremated human remains, radiocarbon dating, stable isotope analysis (carbon, nitrogen, oxygen and strontium) and aDNA analysis has facilitated the exploration and interpretation of later prehistoric social structure and lifestyle. The use of carbon (from enamel carbonate and collagen) and nitrogen stable isotope analysis has highlighted important dietary distinctions between communities inhabiting this region and previous studies from elsewhere in contemporary Europe – specifically a high dependence on millet as a staple crop. This has been evidenced by δ13C values of between -17‰ and -15.3‰ from bone collagen. δ15N values of between 7.6‰ and 9.1‰ support this interpretation as they do not indicate the consumption of marine protein. Increased δ15N values of up to 13.5‰ from deciduous dentine have been interpreted as the influence of dietary and metabolic conditions, particularly in the presentation of an Infant exhibited palaeopathological evidence of severe metabolic disease. Complementary isotopic methods, including oxygen isotope ratios and enamel carbonate carbon, have also highlighted heterogeneity in childhood diet, reflecting the transition from a high lipid diet of breastmilk, to a diet of carbohydrates, indicative of weaning. In addition to these findings, the application of radiocarbon dating on cremated and nio-cremated human bone has expanded the current understanding of mortuary practices in this study area. Inhumation burial, previously thought synomemous with the Iron Age, has been now been identified throughout the Bronze Age at the cemetery of Obrežje. The application of this multi-scalar approach to combining and interpreting these data sets has allowed for the investigation of individual biographies, as well as regional trends. This research illustrates the advantages of bringing together multiple lines of evidence for the creation of informed interpretations regarding the life, death and diet of prehistoric peoples of the East Alpine region, and beyond.
  • Scheduling and Resource Efficiency Balancing. Discrete Species Conserving Cuckoo Search for Scheduling in an Uncertain Execution Environment

    Hu, Yim Fun; Li, Jian-Ping; Bibiks, Kirils (University of BradfordFaculty of Engineering and Informatics, 2017)
    The main goal of a scheduling process is to decide when and how to execute each of the project’s activities. Despite large variety of researched scheduling problems, the majority of them can be described as generalisations of the resource-constrained project scheduling problem (RCPSP). Because of wide applicability and challenging difficulty, RCPSP has attracted vast amount of attention in the research community and great variety of heuristics have been adapted for solving it. Even though these heuristics are structurally different and operate according to diverse principles, they are designed to obtain only one solution at a time. In the recent researches on RCPSPs, it was proven that these kind of problems have complex multimodal fitness landscapes, which are characterised by a wide solution search spaces and presence of multiple local and global optima. The main goal of this thesis is twofold. Firstly, it presents a variation of the RCPSP that considers optimisation of projects in an uncertain environment where resources are modelled to adapt to their environment and, as the result of this, improve their efficiency. Secondly, modification of a novel evolutionary computation method Cuckoo Search (CS) is proposed, which has been adapted for solving combinatorial optimisation problems and modified to obtain multiple solutions. To test the proposed methodology, two sets of experiments are carried out. Firstly, the developed algorithm is applied to a real-life software development project. Secondly, the performance of the algorithm is tested on universal benchmark instances for scheduling problems which were modified to take into account specifics of the proposed optimisation model. The results of both experiments demonstrate that the proposed methodology achieves competitive level of performance and is capable of finding multiple global solutions, as well as prove its applicability in real-life projects.

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