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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

An assessment of corrosion and erosion-corrosion behaviour of austenitic cast iron and surface coatings for pump applications

Xu, Hanchang January 2001 (has links)
No description available.
22

Influences on the food-storing behaviour of the grey squirrel : an investigation into social cognition

Hopewell, Lucy Joanne January 2008 (has links)
This thesis investigated whether a food-storing mammal, the eastern grey squirrel (Sciurus carolinensis), uses social cognitive skills in relation to its caching behaviour and explored whether social cognition really is a specialized adaptation that differs from other cognition by examining how social and non-social learning differ. The influence of social factors on the natural caching behaviour of wild squirrels was studied in the field and the effects of conspecific presence on specific aspects of caching behaviour (learning, memory and recovery) were investigated by testing captive squirrels in the laboratory on social learning and one-trial learning tasks. The squirrels were found to be able to learn by observing a conspecific and learned to make a logical choice more readily than an illogical one. They showed no such bias in a comparable non-social task. They responded flexibly to the presence of conspecifics both in the wild and in the laboratory but the results can be interpreted in terms of responses to observable cues rather than as evidence of higher cognitive skills. In total, this thesis suggests that squirrels use unsophisticated social cognitive strategies in relation to their caching but, the difference found in learning under social and non-social conditions suggests that, although not a highly social species, grey squirrels are particularly prepared to form certain associations with social cues. This offers some support to the theory that factors other than social complexity may lead to the development of the ability to process social information highly effectively.
23

Arquitectura capucha da província da Piedade

Medinas, Vítor Joaquim Fialho January 1994 (has links)
No description available.
24

Sand sources, volumes and movement patterns on Wreck Beach, Vancouver, British Columbia

Pool, Meridith Ines January 1975 (has links)
Along Wreck Beach the existing headland cliffs are eroding and receding under attack from terrestrial and marine agents. Valuable property is being lost and nearby structures endangered. Remedial measures were undertaken in the summer of 1974 to halt wave erosion along the cliff base. A rock groin and sand—gravel protective beach scheme was only partially success ful during the following year. To design an adequate protection system for the cliffs wind and wave effects need to be deter mined to fully understand the resulting sand movement patterns. Understanding the processes affecting Wreck Beach is the first step in controlling them. Methods used to investigate sand movement included field coverage of the study area in photographic form as well as instrument cross—sectioning over a two year period. These data were correlated with historical wind records and predictions from wave refraction diagrams to determine seasonal movement onto and off the beach face and the cyclic progression of sandbars in the longshore current direction. Annual sand trans port volumes, sand supply sources and amounts contributed are outlined. In designing a protection scheme in which longshore trans port requirements must be considered the information and calcu lations suggests that the Fraser River North Arm could amply provide the longshore transport supply requirements. However, some means in addition to the present natural processes must be available to bring this sand into a range where wind gen erated wave activity can incorporate it into the existing Wreck Beach system. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
25

Evaluating Grey-box Models in Highly and Slightly Correlated Imbalanced Data Sets

Khandelwal, Aashish S. January 2010 (has links)
No description available.
26

Brain cortical variability, software, and clinical implications

Mikhael, Shadia S. January 2018 (has links)
It is essential to characterize and quantify naturally occurring morphometric changes in the human brain when investigating the onset or progression of neurodegenerative disorders. The aim of this thesis is to characterize the properties and measure the performance of several popular automated magnetic resonance image analysis tools dedicated to brain morphometry. The thesis begins with an overview of morphometric analysis methods, followed by a literature review focusing on cortical parcellation protocols. Our work identified unanimous protocol weaknesses across all packages in particular issues when addressing cortical variability. The next chapters present a ground truth dataset and a dedicated software to analyse manually parcellated data. The dataset (https://datashare.is.ed.ac.uk/handle/10283/2936) includes 10 healthy middle-aged subjects, whose metrics we used as reference against automated tools. To develop the ground truth dataset, we also present a manual parcellation protocol (https://datashare.is.ed.ac.uk/handle/10283/3148) providing step-by-step instructions for outlining three cortical gyri known to vary with ageing and dementia: the superior frontal gyrus, the cingulate gyrus and the supramarginal gyrus. The software, Masks2Metrics (https://datashare.is.ed.ac.uk/handle/10283/3018), was built in Matlab to calculate cortical thickness, white matter surface area, and grey matter volume from 3D binary masks. Characterizing these metrics allowed further understanding of the assumptions made by software when creating and measuring anatomical parcels. Next, we present results from processing the raw T1-weighted volumes in the latest versions of several automated image analysis tools-FreeSurfer (versions 5.1 and 6.0), BrainGyrusMapping, and BrainSuite (version 13a)- against our ground truth. Tool repeatability for the same system was confirmed as multiple runs yielded identical results. Compared to our ground truth, the closest results were generated by BrainGyrusMapping for volume metrics and by FreeSurfer 6.0 for thickness and surface area metrics. In conclusion, our work sheds light on the significance of clearly detailed parcellation protocols and accurate morphometric tools due to the implications that they both will have. We therefore recommend extra caution when selecting image analysis tools for a study, and the use of independent publicly available ground truth datasets and metrics tools to assist with the selection process.
27

Proposta de um instrumento de medição e avaliação do programa Lean em empresa do segmento químico: segundo abordagem do MDE, base Lesat & Baldrige / Proposal for an instrument of measurement and evaluation of Lean Program in a chemical company: according approach of BDM, basis Lesat & Baldrige

Soares Junior, Epaminondas Rodrigues [UNESP] 26 August 2016 (has links)
Submitted by EPAMINONDAS RODRIGUES SOARES null (soaresep@ig.com.br) on 2016-09-15T12:24:24Z No. of bitstreams: 1 Tese_Epa_15092016.pdf: 3559715 bytes, checksum: f9c8d9306fde4e031595ddab51bed217 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-15T18:40:37Z (GMT) No. of bitstreams: 1 soares_erj_dr_guara.pdf: 3559715 bytes, checksum: f9c8d9306fde4e031595ddab51bed217 (MD5) / Made available in DSpace on 2016-09-15T18:40:37Z (GMT). No. of bitstreams: 1 soares_erj_dr_guara.pdf: 3559715 bytes, checksum: f9c8d9306fde4e031595ddab51bed217 (MD5) Previous issue date: 2016-08-26 / Esta pesquisa teve o objetivo de diagnosticar o nível de maturidade de diversas unidades produtivas de uma empresa do ramo químico e se elas poderiam ser consideradas Classe Mundial, identificando os pontos fortes e fracos da gestão de cada uma das fábricas analisadas, visando buscar oportunidades de melhoria em seu Sistema de Gestão. O método científico utilizado, as limitações da pesquisa e implicações, os resultados de investigação e pesquisa são exploratórios. O estudo foi feito por meio de uma pesquisa tipo Survey por análise combinada inicialmente qualitativa e em seguida quantitativa, referente ao grau de maturidade das empresas analisadas, utilizando-se do método de Análise de Correlação Grey. Referente ao método de pesquisa, foi utilizado o questionário combinado do LAI Enterprise Self-assessment Tool (Lesat) do Massaussuchets Institute of Technology (MIT) e Baldrige Performance Excellence Program do National Institute of of Standards and Techonology (NIST) do United States Department of Commerce, aplicados ao Método de Diagnóstico de Empresas (MDE). Pesquisas futuras podem ser realizadas em estudos de correlação entre um número maior de empresas de manufatura de outros segmentos. Este estudo amplo e com diversidade de organizações proporcionará um melhor entendimento do nível maturidade das organizações. A contribuição do estudo está na capacidade de diagnosticar o nível de maturidade da organização pesquisada. Avaliar se a aplicação das ferramentas do MDE, Lesat, Baldrige e Grey System entre as diversas fábricas de uma empresa do ramo químico pesquisadas têm sido capazes de identificar os pontos fortes e fracos desta organização. O estudo resultou na identificação de uma forma sistêmica de orientar a necessidade de novos projetos e ações para apoiar e elaborar o planejamento estratégico da empresa química pesquisada. / This research had the purpose to diagnose the level of maturity of the several production plants in a chemical industry and evaluate if they could be consider World Class, in order to identify the strengths and weaknesses of the management of each of the analyzed factories, to identify opportunities for improvement in its Management System. The scientific method used, research limitations and implications, the results of investigation and research are exploratory. This study done through a survey type Survey combined qualitative analysis initially and then quantitative, concerning the degree of maturity of the factories analyzed, using Grey Correlation analysis method. Concerning the study method was the combined questionnaire LAI Enterprise Self-assessment Tool (Lesat) of Massachusetts Institute of Technology (MIT) and Baldrige Performance Excellence Program of the National Institute of Standards and Technology (NIST) of the United States Department of Commerce, using the Business Diagnostic Method (BDM). Future research can be carry out and correlation studies among a larger number of other branches manufacturing companies can be perform. A larger study with a diversity of organizations will provide a better understanding of the maturity level of the organizations. The contribution of this study is in the ability to diagnose the organization's maturity level. Evaluate if the application of BDM, Lesat & Baldrige and Grey System tools between the different factories inside a chemical company surveyed have been able to identify the strengths and weaknesses of this organization. The study resulted in the identification of a systemic way to guide the need for new projects and initiatives to support and develop the strategic planning of the chemical company researched.
28

Biology of the Grey-headed gull Larus cirrocephalus in South Africa.

McInnes, Alistair McIntyre. 26 November 2013 (has links)
The biology of the Grey-headed Gull was studied between 2004 and 2005 in South Africa's Gauteng, KwaZulu-Natal and Northern Cape provinces. Grey-headed Gulls have a widespread but patchy distribution in South Africa, occurring both inland and at the coast. Their largest population is centred on Gauteng, where the species appears to be a relatively recent colonizer and where the current breeding population is estimated at 2185 breeding pairs (the largest in South Africa). There is evidence that the species has also increased in other parts of South Africa, especially at Port Elizabeth in the Eastern Cape. The majority of coastal birds are found in KwaZulu-Natal and there is strong evidence for regular movements of adult birds between Durban and Lake St Lucia. By contrast, little evidence was found for a putative large-scale, regular movement between Gauteng and KwaZulu-Natal. The breeding biology of the Grey-headed Gull was studied at four sites in Gauteng and at Lake St Lucia's Lane Island during 2004 and 2005. The distance between the Gauteng sites ranges from 1.7 km, between Lakefield Pan and Korsman's Bird Sanctuary, to 25.3 km, between Bonaero Park and Modderfontein Pan. The approximate distance between Gauteng and Lake St Lucia is 460 km. The mean clutch size at all sites was 2.42 eggs and the mean incubation period was 24.9 days. Parental investment in incubation was approximately equal between the sexes while males spent more time in attendance and participated in more aggressive encounters. Empirical growth curves are given for mass, wing, culmen, head and foot morphometrics of Grey-headed Gull chicks. Intraspecific variation in breeding parameters reveal significant differences between sites, including: highly synchronous laying at Lake St Lucia; the largest eggs and fastest growing chicks at Gauteng's Modderfontein Pan (a small, peripheral colony); and the smallest eggs and slowest growing chicks at Gauteng's Lakefield Pan (a large, 'core' colony). Possible reasons for these differences include the relative localities of each site in terms of feeding opportunities, high levels of predation by African Fish Eagle's at Lane Island, and density dependent factors operating on the large colonies within the core population on Gauteng's East Rand. Overall daily egg survival was comparatively high for all sites in Gauteng and low for Lane Island nests. Morphometric, plumage and bare-parts data from a sample of trapped and resighted birds are used to age, sex and determine the timing and duration of moult in the Greyheaded Gull. Six age classes were identified and, for all measurements, males were significantly larger than females. The mean duration of primary moult was 136 days between October and January and there were two waves of secondary moult. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
29

Grey Optimization For Uncertainty Modeling In Water Resources Systems

Karmakar, Subhankar 06 1900 (has links)
In this study, methodologies for modeling grey uncertainty in water resources systems are developed, specifically for the problems in two identified areas in water resources: waste load allocation in streams and floodplain planning. A water resources system is associated with some degree of uncertainty, due to randomness of hydrologic and hydraulic parameters, imprecision and subjectivity in management goals, inappropriateness in model selection, inexactness of different input parameters for inadequacy of data, etc. Uncertainty due to randomness of input parameters could be modeled by the probabilistic models, when probability distributions of the parameters may be estimated. Uncertainties due to imprecision in the management problem may be addressed by the fuzzy decision models. In addition, some parameters in any water resources problems need to be addressed as grey parameters, due to inadequate data for an accurate estimation but with known extreme bounds of the parameter values. Such inexactness or grey uncertainty in the model parameters can be addressed by the inexact or grey optimization models, representing the parameters as interval grey numbers. The research study presented in this thesis deals with the development of grey and fuzzy optimization models, and the combination of the two for water resources systems decision-making. Three grey fuzzy optimization models for waste load allocation, namely (i) Grey Fuzzy Waste Load Allocation Model (GFWLAM), (ii) two-phase GFWLAM and (iii) multiobjective GFWLAM, and a Grey Integer Programming (GIP) model for floodplain planning, are developed in this study. The Grey Fuzzy Waste Load Allocation Model (GFWLAM) for water quality management of river system addresses uncertainty in the membership functions for imprecisely stated management goals of the Pollution Control Agency (PCA) and dischargers. To address the imprecision in fixing the boundaries of membership functions (also known as membership parameters), the membership functions themselves are treated as imprecise in the model and the membership parameters are expressed as interval grey numbers. The conflict between the fuzzy goals of PCA and dischargers is modeled using the concept of fuzzy decision, but because of treating the membership parameters as interval grey numbers, in the present study, the notion of ‘fuzzy decision’ is extended to the notion of ‘grey fuzzy decision’. A terminology ‘grey fuzzy decision’ is used to represent the fuzzy decision resulting from the imprecise membership functions. The model provides flexibility for PCA and dischargers to specify their aspirations independently, as the membership parameters for membership functions are interval grey numbers in place of a deterministic real number. In the solution, optimal fractional removal levels of the pollutants are obtained in the form of interval grey numbers. This enhances the flexibility and applicability in decision-making, as the decision-maker gets a range of optimal solutions for fixing the final decision scheme considering technical and economic feasibility of the pollutant treatment levels. The methodology is demonstrated with the case studies of a hypothetical river system and the Tunga-Bhadra river system in Karnataka, India. Formulation of GFWLAM is based on the approach for solving fuzzy multiple objective optimization problem using max-min as the operator, which usually may not result in a unique solution. The two-phase GFWLAM captures all the alternative optimal solutions of the GFWLAM. The solution technique in the Phase 1 of two-phase GFWLAM is the same as that of GFWLAM. The Phase 2 maximizes upper bounds and minimizes lower bounds of decision variables, keeping the optimal value of goal fulfillment level same as obtained in the Phase 1. The two-phase GFWLAM gives the unique, widest, intervals of the optimal fractional removal levels of pollutant corresponding to the optimal value of goal fulfillment level. The solution increases the widths of interval-valued fractional removal levels of pollutants by capturing all the alternative optimal solutions and thus enhances the flexibility and applicability in decision-making. The model is applied to the case study of Tunga-Bhadra river system, which shows the existence of multiple solutions when the GFWLAM is applied to the same case study. The width of the interval of optimal fractional removal level plays an important role in the GFWLAM, as more width in the fractional removals implies a wider choice to the decision-makers and more applicability in decision-making. The multiobjective GFWLAM maximizes the width of the interval-valued fractional removal levels for providing a latitude in decision-making and minimizes the width of goal fulfillment level for reducing the system uncertainty. The multiobjective GFWLAM gives a new methodology to get a satisfactory deterministic equivalent of a grey fuzzy optimization problem, using the concept of acceptability index for a meaningful ranking between two partially or fully overlapping intervals. The resulting multiobjective optimization model is solved by fuzzy multiobjective optimization technique. The consistency of the solution is verified by solving the problem with fuzzy goal programming technique. The multiobjective GFWLAM avoids intermediate submodels unlike GFWLAM, so that the solution from a single deterministic equivalent of the GFWLAM adequately covers all possible situations. Although the solutions obtained from multiobjective GFWLAM provide more flexibility than those of the GFWLAM, its application is limited to grey fuzzy goals expressed by linear imprecise membership functions only, whereas GFWLAM has the capability to solve the model with any monotonic nonlinear imprecise membership functions also. The methodology is demonstrated with the case studies of a hypothetical river system and the Tunga-Bhadra river system in Karnataka, India. The Grey Integer Programming (GIP) model for floodplain planning is based on the floodplain planning model developed by Lund (2002), to identify an optimal mix of flood damage reduction options with probabilistic flood descriptions. The model demonstrates how the uncertainty of various input parameters in a floodplain planning problem can be modeled using interval grey numbers in the optimization model. The GIP model for floodplain planning does not replace a post-optimality analysis (e.g., sensitivity analysis, dual theory, parametric programming, etc.), but it provides additional information for interpretation of the optimal solutions. The results obtained from GIP model confirm that the GIP is a useful technique for interpretation of the solutions particularly when a number of potential feasible measures are available in a large scale floodplain planning problem. Though the present study does not directly compare the GIP technique with sensitivity analysis, the results indicate that the rigor and extent of post-optimality analyses may be reduced with the use of GIP for a large scale floodplain planning problem. Application of the GIP model is demonstrated with the hypothetical example as presented in Lund (2002).
30

Grey Owl, les autochtones et la perception environnementale au Canada au début du XXe siècle / Grey Owl, les autochtones et la perception environnementale au Canada au début du 20e siècle / Grey Owl, les autochtones et la perception environnementale au Canada au début du vingtième siècle

Sähr, Sylvia 12 April 2018 (has links)
À travers l’analyse du discours environnemental de l’auteur et conférencier Grey Owl (1888 – 1938), ce mémoire constitue une étude de la perception environnementale des cultures autochtones et occidentales au Canada au début du XXe siècle. L’objectif est d’identifier la perception environnementale dans sa dépendance de l’état de la Nature, de l’époque et de la culture de l’individu et de la société. Avant-gardiste, Grey Owl intégrait des éléments des concepts de mode de vie durable et d’écotourisme dans son discours. Il représentait également l’ambivalence des sociétés occidentales envers la Nature. Sans sa transformation en Autochtone, cet Anglais aux cheveux longs n’aurait pu faire connaître au grand public la nécessité de sauver la Wilderness et les cultures autochtones. Il a contribué à l’image romantique créée des Autochtones par des Occidentaux. Encore aujourd’hui, longtemps après la colonisation, les Autochtones, peuples chers à Grey Owl, ressentent une perte d’identité. / Through an analysis of the environmental discourse of the author and speaker Grey Owl (1888 – 1938), this thesis studies the environmental perception of Native and Western cultures in Canada in the early 20th century. The objective is to identify the environmental perception in its dependency of the state of Nature, the epoch and the culture of the individual and the society. Avant-gardist, Grey Owl integrated elements of a sustainable way of life and ecotourism in his discourse. He too represented the ambivalence of Western societies to the Nature. Without his transformation into a Native, this Englishman with his long hair could not have made known the necessity of saving the wilderness and the native cultures to a wide audience. He contributed to the romantic image created from the Natives by the Western societies. Still today, long after the colonization, the Natives, peoples dear to Grey Owl, feel a loss of identity.

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