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Developing a compositional ontology alignment framework for unifying business and engineering domainsAzzam, Said Rabah January 2012 (has links)
In the context of the Semantic Web, ontologies refer to the consensual and formal description of shared concepts in a domain. Ontologies are said to be a way to aid communication between humans and machines and also between machines for agent communication. The importance of ontologies for providing a shared understanding of common domains, and as a means for data exchange at the syntactic and semantic level has increased considerably in the last years. Therefore, ontology management becomes a significant task to make distributed and heterogeneous knowledge bases available to the end users. Ontology alignment is the process where ontology from different domains can be matched and processed further together, hence sharing a common understanding of the structure of information among different people. This research starts from a comprehensive review of the current development of ontology, the concepts of ontology alignments and relevant approaches. The first motivation of this work is trying to summarise the common features of ontology alignment and identify underdevelopment areas of ontology alignment. It then works on how complex businesses can be designed and managed by semantic modelling which can help define the data and the relationships between these entities, which provides the ability to abstract different kinds of data and provides an understanding of how the data elements relate. The main contributions of this work is to develop a framework of handling an important category of ontology alignment based on the logical composition of classes, especially under a case that one class from a certain domain becomes a logic prerequisites (assumption) of another class from a different domain (commitment) which only happens if the class from the first domain becomes valid. Under this logic, previously un-alignable classes or miss-aligned classes can be aligned in a significantly improved manner. A well-known rely/guarantee method has been adopted to clearly express such relationships between newly-alignable classes. The proposed methodology has be implemented and evaluated on a realistic case study.
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Analysis of human electrocardiogram for arrhythmia auto-classification and biometric recognition systems using analytic and autoregressive modeling parametersAlhamdi, Mustafa January 2015 (has links)
The electrocardiogram is a skin surface measurement of the electrical activity of the heart over time. This activity is detected by electrodes attached to the surface of the skin and recorded or displayed by an external medical device. Doctors use electrocardiograms to detect and diagnose conditions such as arrhythmias (abnormal heart rhythms) and myocardial infarctions (heartattacks). The work described in this thesis investigates the system designed for two primary applications, electrocardiogram classification system based on autoregressive models which identifies normal (healthy) from abnormal (unhealthy) electrocardiogram signals and the electrocardiogram biometric system based on analytic and modeling features which identifies each person individually from his or her electrocardiogram. In recent years, a number of signal processing techniques have been used to design electrocardiogram signal auto-classification and biometric identification systems. electrocardiogram classification and biometric systems implemented in this thesis are compared with a number of other recently described techniques and methods to identify electrocardiogram signals. The aim of any designed electrocardiogram classification and biometric system described in this work is to achieve high accuracy rate when identifying electrocardiograms. Electrocardiogram classification and biometric systems consists of four major stages, pre-processing of electrocardiogram signal, QRS complex detection, feature extraction and classification algorithms. Each of those steps are discussed and explained in separate chapters with variety of techniques and methods employed to achieve each step. Developed systems based on autoregressive models to design electrocardiogram classification and biometric achieved accurate correct classification rate with high level of productivity due to the small number of extracted parameters using autoregressive models. The proposed electrocardiogram classification and biometric systems of this work achieved 100 % correct classification rate in identifying normal from abnormal electrocardiogram signals and each person individually from his or her electrocardiogram signal. In this work, it has been proven that autoregressive models can represent electrocardiogram signals with 91 % accuracy and matching between the original electrocardiogram signal and the modeled signal.
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A study of the implementation of quality management systems (QMS) within the Kuwaiti manufacturing industryAl-Khadher, Abdullah M. Kh. M. January 2015 (has links)
The intended contribution and unifying purpose of this research was to identify the enablers and barriers affecting the implementation of quality management systems (QMS) within the Kuwaiti industrial context. This was achieved by assessing the current practices adopted by a number of manufacturing firms in Kuwait and then the gaps or areas that need to be filled were measured. QMS is defined as an organisation’s structure, responsibilities, processes, procedures and resources which guide and control an organisation with regard to quality in order to constantly improve the effectiveness and efficiency of its performance. QMS enables businesses to minimise undesired impacts on the processes while maximising the effectiveness and efficiency of those processes that deliver products or services to end-users. This PhD research focuses on identifying the general state of the manufacturing sector within Kuwaiti Small, Medium and Large Enterprises (KSMLEs) and analyses links, enablers and barriers related to the implementation of QMS by linking the possible effects of culture. The research was carried out using a case study as well as the mixed methods approach involving the use of both quantitative and qualitative research methods. In the first instance a single case study organisation involving a large sized enterprise within the Kuwaiti manufacturing sector was researched into as a pilot study. This helped in refining both the quantitative survey questionnaire and the qualitative interview questions. Thereafter, for the quantitative approach, a total of 192 valid responses out of 308 received data sets involving KSMLEs that included three different levels of management (top, middle and shop floor) were generated using physical and online-surveys, the target participants being managers working in the industrial sector in Kuwait. The qualitative research design included twenty-five interviews involving twenty-five KSMLEs, also at different management levels (six top, six middle and thirteen shop floor managers) in the manufacturing sector in Kuwait. Findings from this study confirmed that leaders and managers of the manufacturing sector in Kuwait are actively engaged with customers. However, they lack the process of delegating tasks and empowering of people. Findings further suggest that firms’ strategy must focus on appreciating cultural aspects such organisational culture, investing in employees, developing training programmes, and addressing community and social responsibility. This study contributes to the body of knowledge on QMS and provides a viable framework (model) that was over time developed through an iterative series of revisions, literature review, a case study and expert views. The new model designed and proposed in this thesis is called the Kuwait Quality Culture Model (KQCM). This model portrays the importance of culture along with other factors in the initiation and the implementation of QMS, particularly in Arabic culture. Overall findings confirm the researcher expectation that QMS performance (managing people, policy & strategy, partnerships & resources, and culture) is positively associated to commitment and leadership of top management and those managers at different levels stress on the importance and necessity of internal communication channels. Moreover, employees’ empowerment and relevant processes (people, policy & strategy, partnerships & resources, and culture) are crucial in implementing any quality practices. Furthermore, culture was found to be a vital factor as it plays an important role in the implementation of QMS in Kuwait. Finally, when implemented, the study confirmed that KQCM results (people, customers and society) would lead to better organisational performance.
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A context-aware framework for personalised recommendation in mobile environmentsYeung, Kam Fung January 2011 (has links)
Context-awareness has become an essential part in various personalised applications such as mobile recommeder systems and mobile information retrieval. Much progress has been made in context-aware applications. However there is a lack of general framework for supporting the rapid development of context-aware applications and enabling the sharing and dissemiation of context information across different applications
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Novel nano-particulate/polymer treatment systems for masonry enhancement and protectionMacMullen, James January 2012 (has links)
Fundamental issues associated with addressing the UK housing shortage problem are climate change and the lack of usable building space. Conservation of old buildings, maintaining green land and a country filled with single walled older properties mean that the UK government has to retrofit existing older building stock. This would make a significant impact on reducing the carbon footprint of each household as well as to alleviate energy supply problems. The investigation of novel zinc oxide and titanium dioxide nanoparticulates in aqueous silane/siloxane oil-in-water (O/W) emulsions for practical exterior facade applications is presented. An initial emulsion was developed and optimised before further improvement through nanoparticulate incorporation was achieved. Nanoparticulates of zinc oxide and titanium dioxide were dispersed respectively using ultrasonication in n-isooctyltriethoxysilane before being incorporated into a base emulsion. Once formulations were optimised, applied studies and fundamental assessment of these emulsions were conducted. The aim of the work presented was to produce a practical facade emulsion that could be used in the retrofitting of existing building stock or for heritage remedial treatments. Initial research indicated that water was the governing factor in a diverse range of facade degradation mechanisms; improving water repellence, thermal envelope efficiency while reducing biofouling was recognised as being of key interest in this field. The study gives insight into aqueous water repellent emulsions, nanoparticulate integration by commercially practical means, and assessment of the attributes exhibited by such treatments. Rheological and morphological characterisation concluded that a gelled network structure is produced by the incorporation of the fabricated nanoparticulate colloids. The emulsions retained shear-thinning characteristics, ideal for deep treatment penetration to be achieved for porous silicate substrates. Accelerated ageing tests showed that the nanoparticulate emulsions were substantially more thermodynamically stable than the emulsion control while also being physically more stable due to surfactant-particulate stabilisation mechanisms of the polar phases. From further investigation it was also found that hydroxyl terminated siloxane could be integrated into these emulsions, helping to improve the ‘green credentials’ of such systems through the replacement of conventionally used trimethoxy terminated siloxanes, that release harmful methanol upon curing, thus substitution is preferential and in line with current European policy. Treatments improved thermal envelope efficiency of structures through the reduction of retained water in various forms including rising damp. Assessment was carried out using model houses exposed to various temperature and humidity scenarios under controlled heating. The findings showed that water was the root cause of heat loss and thus a key parameter when considering the improvement of a structures’ carbon footprint. These treatments allow water vapour to permeate out of a structure passively, reducing internal humidity issues including microbiological degradation and health related problems experienced by occupants. Investigation of bioreceptivity conducted though an 8 week algal culture streaming study concluded that treatments with <0.1wt% of the aforementioned nanoparticulates could reduce biofouling through photo-induced sanitisation. Furthermore, it was also found that while water repellence may vary at the facade interface due to the respective metal oxides photocatalytic nature, substrate interior water contact angles should remain high due to the absence of UV light. This is of key importance as it implies that simultaneous antifouling and rising damp remediation may be achieved by such treatments. One of the major advantages of the treatments presented is that they do not effectively alter the aesthetics of the substrate, unlike photo-induced ‘self-cleaning’ coatings that turn the facade white. In addition, these treatments are not susceptible to problems related to the cracking or chipping of coated surfaces, allowing them to provide better protection. From the above points it is clear that these treatments are the next paradigm in facade protection, complying with current social, ecological, political and industrial needs. This study presents the inception, development and investigation of key attributes and mechanisms of these novel treatments while showing critically that such emulsion treatments are practical with great potential to enhance the lives of UK residents.
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An intelligent monitoring system to predict potential catastrophic incidentsPainting, Andrew David January 2014 (has links)
This dissertation identified a gap in research for an intelligent monitoring system to monitor various indicators within complex engineering industries, in order to predict the potential situations that may lead to catastrophic failures. The accuracy of prediction was based upon lessons learnt from historic catastrophic incidents. These incidents are normally attributed to combinations of several minor errors or failures, and seldom occur through single point failures. The new system to monitor, identify and predict the conditions likely to cause a catastrophic failure could improve safety, reduce down time and prioritise funding. This novel approach involved the classification of ten common traits that are known to lead to catastrophe, based on six headings used by the Health and Safety Executive and four headings used in Engineering Governance. These were weight averaged to provide a ‘state’ condition for each asset, and amalgamated with a qualitative fault tree representation of a known catastrophic failure type. The information on current ‘state’ was plotted onto a coloured 2D surface graph over a period of time to demonstrate one particular visual tool. The research demonstrated that it was possible to create the monitoring system within Microsoft Excel and to run Visual Basic programs alongside Boolean logic calculations for the fault tree and the predictive tools, based upon the trend analysis of historic data. Another significant research success was the development of a standardised approach to the investigation of incidents and the dissemination of information.
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Pedestrians counting and event detection in crowded environmentShbib, Reda January 2015 (has links)
Crowd density estimation and pedestrian counting are becoming an area of interest such as assessing the social effect and impact between small groups of people within a crowd. Still, existing experimental crowd analyses performed by operators are time consuming. Generally, human controllers are engaged to achieve this task, however, more and more, visual surveillance are becoming an essential need, it is a hard task to watch and study all recorded video due to the huge number of cameras being installed. Currently, image-processing field has attracted all academic and research to develop automatic counting and monitoring algorithms. In this thesis, some novel contributions in different fields are presented: pedestrian counting, event detection, and queue monitoring. Firstly, this thesis presents an original contribution in the pedestrian counting domain. In recent years, many of proposed counting techniques have used global features to estimate crowd density. In this thesis, a new approach has been introduced to replace global image features by the low level- features, which are specific to individuals and clusters within the crowd. Thus, the total number of pedestrians is the summation of all clusters, which construct the crowd. Experimental results through different datasets showed that low-level features have performed better than global features. In addition to the pedestrian counting, this thesis presents another contribution in the area of pedestrian flow monitoring through the developing of a virtual door algorithm, in which pedestrians are counted while they are passing through a proposed virtual count line. Important features have been extracted from the region of interest. Discriminant features are detected, and optical flow of these points are assembled .The proposed system assembles optical flow in the trajectory direction in a discrete group of extracted feature points. Finally, this thesis presents a novel technique for estimating queue parameters, such as number of entrance, leaving and the frequency, in order to obtain a clear picture about the queue traffic and flow. Therefore, in order to obtain these parameters, the proposed pedestrian counting and virtual door approach have been integrated together. Experimental results conducted demonstrate that the proposed system is strong to real-life environments.
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The manufacture, properties and characterisation of layered silicate reinforced spent polymer nanocompositesAldousiri, Barjas January 2011 (has links)
This research work deals with the manufacture, properties and characterisation of layered silicate (LS) reinforced novel spent polymer nanocomposites. Three different materials used for nanocomposites preparation were polyamide 12 (PA-12), DuraForm polyamide 11 (EX) and Glass Filled polyamide 12 (GF-12). Various concentrations (1, 3, 5 and 7 wt. %) of the layered silicates were dispersed in three different types of spent polyamide matrix by the melt compounding method, in order to investigate the effect of LS reinforcement on mechanical and thermal properties of spent polymer. The interlayer d-spacing, interlamellar structure and surface morphologies were investigated by wide angle x-ray diffraction (WXRD), transmission electron microscope (TEM) and scanning electron microscope (SEM), respectively. The tensile strength and modulus of the un-reinforced spent PA-12 samples were found to increase with the incorporation of LS. This improvement in the tensile strength and modulus appear to be directly related to the LS loading. Similarly, the flexural strength and modulus were found to increase significantly with incorporation of the LS reinforcement. Nanoindentation test results were used to evaluate the nanomechanical properties (i.e. hardness and modulus) of spent PA-12/nanocomposites. The results show that the hardness and modulus of LS reinforced spent PA-12 nanocomposites were higher compared to the un-reinforced spent PA-12 sample. Crystallisation temperature measured using DSC showed a gradual decrease as the LS loading increased. For spent PA-12 nanocomposites samples the melting temperature slightly increased with 1 and 3 wt. % of LS loading when compared with the unreinforced spent PA-12 sample. However, samples with 5 and 7 wt. % of LS have approximately the same melting temperature of the un-reinforced spent PA-12 sample. Glass transition temperature (Tg) of the spent PA-12 nanocomposites slightly decreased in comparison to the un-reinforced spent PA-12 sample. It was found that the incorporation of LS does not affect or improve the tensile strength and modulus of the spent EX nanocomposites. However, flexural strength and modulus for the spent EX nanocomposites are improved when compared with the un-reinforced spent EX sample. The nanoindentation results show that as the LS concentration increased up to 3 wt.%, the hardness and modulus were improved. Different levels of layered silicates dispersion as characterised by XRD, TEM and SEM correlated strongly with improvements in mechanical and thermal performances. The crystallisation temperature of spent EX and GF-12 nanocomposites samples shows gradual increases with increasing LS loading. The measured crystallisation temperature was approximately 6˚C higher for the spent EX nanocomposites samples than for the un-reinforced spent EX sample. Secondary heating of the un-reinforced spent EX sample and the nanocomposites samples resulted in an increase in melting temperature which corresponded to increasing LS loading. However, the melting temperature for all the spent GF-12 nanocomposites samples was similar to the one for the un-reinforced spent GF-12 sample. It was found that Tg values decreased with increased in LS loading for spent GF-12 samples. The presence of layered silicate did not contribute in improving tensile and flexural strength of spent GF-12 matrix. However, the hardness and elastic modulus were found to increase with increased layered silicates loading up to 7 wt.%.
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Finite element studies of femoroacetabular impingementHellwig, Felix Lutz January 2013 (has links)
Recently, femoroacetabular impingement (FAI) was introduced as a pathomechanical concept that could explain idiopathic cartilage and labral degeneration. FAI can be subdivided into three mechanisms: 'Cam'- and 'pincer'-type impingement and the 'contracoupe' mechanism. The suggested concept aims to create a link between retrospective findings of cartilaginous tissue degeneration and mild abnormal structural deformations of the hip joint. The theoretical concept focuses on abnormal articulation rather than increased axial-overloading. Although clinical evidence seems to be given, prospective biomechanical verification would be desirable to provide further justification for early joint reconstruction surgery. A comprehensive research program has been carried out to highlight elevated stresses, contact pressures, affected fluid-load support, abnormal articulation and increased femoral head motion evoked by mild to severe abnormal conditions of the hip joint. Contact pressure, stress distributions and femoral head motion, indicating joint stability, were studied using three dimensional finite element models of normal and abnormal hip joint conditions; the considered abnormal conditions included a varying degree of acetabular and femoral version and manifestation of femoral protrusions (hump) at the femoral head-neck junction. The cartilogenous tissues were considered as linear elastic isotropic materials. The highlighted abnormal articulation confirmed the suggested concept of FAI; the predicted abnormal stress and contact pressure distribution corresponded to clinical findings. The fluid-load support, solid-on-solid stress, stress components, within the solid extracellular matrix of the cartilaginous tissues, and total contact pressure were studied during normal and isolated 'cam'-type impinged articulation. The cartilogenous tissues were considered as linear biphasic orthotropic materials. While the maximum total contact pressure, predicted during distinct 'cam'-type impingement, did not exceed the maxima obtained for normal articulation, the fluid-load support was severely affected at the zone of impingement. Vigorous elevated solid-on-solid stresses found at the zone of impingement, suggest a local increase in the coefficient of friction, which might lead to cartilage wear and progresses to severe osteoarthritis.
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Development of a quality management model for Thai Small, Medium and Large Enterprises (SMLEs)Kluaypa, Prawate January 2013 (has links)
A quality management (QM) model is broadly accepted as a tool of managerial approaches in order to measure and improve the performance of the organisation. However, the existing QM models, such as the Thailand Quality Award (TQA), may not be appropriate to employ in Thai Small, Medium and Large Enterprises (SMLEs). Due to the TQA‟s vigorous requirements, there are only a few Thai companies that have achieved the TQA. Moreover, recent research studies on the QM model have focused on other Thai industries and not directly Thai SMLEs, whereas Thai SMLEs generate a lot of income for the country and require an effective QM model in order to improve their organisational performance continuously. The aim of this current research is to develop and evaluate a QM model for assessing organisational performance in Thai SMLEs. The research methodology used in this research involves two main studies. Firstly, the theoretical study aims to develop a conceptual QM model and a conceptual Confirmatory Factor Analysis (CFA) model. Secondly, the empirical study aims to validate a conceptual QM model to be an implemented QM model and to assess a conceptual CFA model to be an implemented CFA model in order to determine the weights of quality elements. An implemented QM model integrated with the weights of quality elements becomes a finalised QM model according to the aim of the research. The important findings of this research are the finalised QM model named as the Thai Small Medium and Large Enterprises Quality (TSMLEQ) model. The TSMLEQ model is composed of 14 elements and their weights: Leadership (53), Strategic Planning & Policy (75), Human Resource Management (71), Partnerships & Resources (69), Knowledge Management (71), Innovation Management (76), Technology Management (66), Process Management (81), Customer Satisfaction (78), Employee Satisfaction (70), Society Results (67), Business Performance Results (76), Continuous Improvement (78), and Measurement & Analysis (69). The main originality of this research compared to the previous study is the determination of the most and least important quality elements, which are Process Management and Leadership, respectively. In order to improve the performance of the organisation, the companies can use the TSMLEQ model as a self-assessment tool to evaluate the level of the quality management implementation. The self-assessment can engage the TQM programme within the companies because it supports as a baseline and path of continuous improvement. The criteria of self-assessment (or quality elements) of the TSMLEQ model are based on the concepts of TQM that are similar to the world-class performance criteria such as the Malcolm Baldrige National Quality Award (MBNQA) and the European Foundation for Quality Management (EFQM). The contributions of this research comprise three aspects. Firstly, Thai industry can be benefitted by adopting the results of this research in order to implement quality management effectively. Secondly, academics in quality management can deploy research methodology used in this research in order to develop a QM model for their research objectives. Thirdly, the findings of this research can be the source of the study of quality management in Thailand and other countries. Keywords: Quality management model, quality elements, Thai small medium and large enterprises, weights, exploratory factor analysis, confirmatory factor analysis
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