Thèses : « 35L70 »

1

Mokhtari, Yacine. « Stabilisation et contrôle de quelques systèmes hyperboliques ». Electronic Thesis or Diss., Bourgogne Franche-Comté, 2021. http://www.theses.fr/2021UBFCD024.

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Cette thèse est consacrée à l’étude de deux problèmes issus de la théorie du contrôle des EDP. Dans un premier temps, on étudie le comportement asymptotique de la solution du système de von Kàrmàn viscoélastique unidimensionnel avec retard. On montre que ce dernier est bien posé dans un espace fonctionnel convenable en utilisant la méthode de Faedo-Galerkin. Pour établir notre résultat de stabilité, on utilise la méthode de Lyapunov en construisant une fonctionnelle adéquate. Dans un deuxième temps, on étudie le problème de la contrôlabilité et de la stabilisation par le bord pour l’équation des ondes unidimensionnelle dans un domaine non cylindrique. Pour la contrôlabilité, on utilise la méthode des caractéristiques pour construire l’unique solution du problème. Nous sommes alors capables de donner l’expression explicite du contrôle pour lequel le système atteint le point d’équilibre après un certain temps. De plus, on montre que ce temps est optimal. Pour la stabilisation, nous fournissons une condition nécessaire et suffisante pour que l’énergie du système décroisse à un taux prédéterminé. De plus, l’influence de la géométrie du domaine et l’influence d’un amortisseur dépendant du temps sont clarifiées. Dans un troisième temps, on étudie la contrôlabilité par le bord de deux ´équations d’ondes couplées par un couplage d’ordre un avec coefficients qui dépendent de l’espace et du temps. On fournit une condition nécessaire et suffisante pour la contrôlabilité exacte en haute fréquences dansle cas général et pour la continuation unique dans le cas cascade
This thesis is devoted to the study of two problems related to the theory of control of PDE.In a first time, we study the asymptotic behavior of the solution to the one-dimensional viscoelastic von Kàrmàn system with delay. We prove that the latter system is well-posed in a suitable functional space using the Faedo-Galerkin method. To establish our stability result, we employ the Lyapunov method by using a suitable candidate functional.In a second time, we study the problem of boundary controllability and stabilization for the one-dimensional wave equation in non-cylindrical domains. For the controllability, one uses the characteristics method to build the unique solution. We will then be able to give the explicit expression of the controls for which the system reaches the equilibrium point after a certain time. Moreover, we show that this time is optimal.For the stabilization, we provide a necessary and sufficient condition that guarantees the energy decay at any desired rate. In addition, the influences of the domain geometry and time-dependent feedback are clarified. In a third time, we study the boundary controllability of two coupled one-dimensional wave equations with first-order coupling terms with coefficients depending on space and time. We give a necessary and sufficient conditions for both exact controllability in high frequency in the general case and for the unique continuation in the cascade case

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2

Wright, Len Tiu. « A comparative study of the marketing strategies of American, British and Japanese companies in the UK market ». Thesis, University of Warwick, 1991. http://wrap.warwick.ac.uk/35770/.

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This thesis presents the product of the research into the comparative marketing strategies of competing American, British and Japanese companies in the UK market. These companies were drawn from the audio/hi-fl, ball bearing, machine tools, microwave ovens and photocopier industries. A. The aims of the research were: i) to investigate and compare a matched sample of subsidiaries of the three national parent companies to discover whether there were significant differences in the way that these subsidiaries went about their business of marketing; ii) to identify which marketing applications, supported by behavioural and organisational differences, contributed to the achievement of effective marketing strategies; iii) to examine headquarters-subsidiary relationships regarding the extent of overseas headquarter's support for its UK subsidiary's marketing operations; and iv) to discover whether there were any pointers to change which would be beneficial in the marketing organisation or operations of UK firms seeking to improve their marketing strategies and performances in these industries. Suitable hypotheses indicated by possible gaps in the literature review were prepared for investigation and testing in order to achieve these aims. The literature review discussed in this thesis also highlighted the difficulties faced by UK firms and the challenges posed by overseas companies in the changed international business conditions from the 1980s to 1991.

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Delcourt-Lancon, Alice. « Electrochemical analysis supported by macro and microelectrode array ». Thesis, Durham University, 2011. http://etheses.dur.ac.uk/3570/.

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The purpose of this project was to investigate cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) analytical techniques for enantioselective sensing at both a macroelectrode and a microelectrode array. The scale of the electrochemical cell was reduced from macro to micro dimensions to improve both the electroanalytical detection and the efficient use of chemicals. A microdevice was fabricated using photolithography and plasma bonding and consisting of a microelectrode array (MEA) of 306 microelectrodes, each with a diameter of 45 µm supported by a polydimethylsiloxane (PDMS) slab engraved with microfluidic channels. The electroanalytical performances of the microdevice were characterised using cyclic voltammetry and it was established that the metallisation process influenced the surface roughness of the electrode, and also affected the final response of the array. The microdevice was used for flow injection analysis using chronoamperometry and provided the capability to detect small changes of analyte concentration. The selective electro-oxidation of phenylethanol catalysed by TEMPO and (-)-sparteine at a macroelectrode and MEA was investigated. The CV analysis showed a reproducible selective oxidation in favour of the (-)-phenylethanol enantiomer. The performances of the electrodes were enhanced to improve their enantioselective capability, and to extend their application to biosensors by functionalising their surface with Self-Assembled Monolayers (SAM). The electrodes were modified with glutathione and cysteine chiral molecules to investigate their ability to recognise the proline enantiomers using EIS analysis. The electron transfer rate of the ferricyanide analyte at the cysteine monolayer was less in the presence of D proline than it was in the presence of L-proline, indicating the selective penetration of the enantiomer through the monolayer. The properties of the macroelectrode and MEA were extended to biological applications by modifying their surfaces with thiolated single stranded DNA.

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Hakimi, Hamid. « The interation of lipopolysaccharide with human spermatozoa : particular relevance to Chlamydia trachomatis ». Thesis, University of Sheffield, 2005. http://etheses.whiterose.ac.uk/3570/.

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Chlamydia trachomatis is an obligate intracellular bacterium which causes the most prevalent sexually transmitted bacterial infection throughout the world. According to the World Health Organization, at least 90 million chlamydial infections are detected annually worldwide. While the role of C. trachomatis in female infertility is well established, data revealing that this organism cause male infertility are still controversial. In this study the effect of "home-made" C. trachomatis LPS and two LPS fractions, lipid A and Kdo on human spermatozoa were investigated in detail. The effect of heated C. trachomatis elementary bodies (EBs) on the viability of spermatozoa and the potency of C. trachomatis LPS in comparison with three LPSs from the Enterobacteriaceae family were also studied. Treatment of spermatozoa with heated-EBs caused a significant increase in sperm death rate and revealed that the toxic component of EB was LPS which is a heat-stable complex. Incubation of spermatozoa with chlamydial LPS showed that this LPS at a concentration of 0.1 pg/m1 induced significant death of spermatozoa, whereas LPSs from E. coli, Kpneumoniae, and S. marcescens, did so only at 50 µg/ml. The effect of the two main LPS fractions of C. trachomatis, lipid A and Kdo, on spermatozoa was also investigated. A small amount of lipid A was isolated from chlamydial LPS and Kdo was purchased. Spermatozoa were treated with these fractions separately. Kdo was shown to be as spermicidal as lipid A, however, unlike lipid A, Kdo was not affected by anti-CD14 antibody or polymyxin B. In an attempt to clarify the mechanism of interaction of chlamydial LPS with spermatozoa and the role of the TLR pathway and TNF-a production, an experimental model using HeLa and THP-1 cell lines was prepared. Because of a lack of a sufficient amount of chlamydial lipid A, lipid A like Kdo was also obtained commercially. While chlamydial LPS and commercial lipid A were able to signal via TLR2 and/or TLR4 in transfected HeLa cells and to induce TNF-a production in THP-1 cells, Kdo failed either to signal through TLRs or stimulate TNF-a secretion. Finally, the role of chlamydial LPS, lipid A or Kdo in ROS production which could potentially induce sperm death, and the mechanism of sperm death induced by these fractions were also studied. In this investigation, spermatozoa were pre- incubated with five ROS scavengers; ascorbic acid, catalase, reduced glutathione, superoxide dismutase (SOD), and a-tocopherol, prior to treatment with the above- mentioned fractions. ROS scavengers used in this investigation neutralised the spermicidal activity of the fractions. It is suggested that these fractions possibly induce their pathogenic effect via ROS production. Results from an annexin V/PI binding assay and quantitation of caspase-3 activity in spermatozoa stimulated with chlamydial LPS, Kdo, and lipid A revealed that LPS and its fractions induced sperm apoptosis which was primarily caspase-mediated. In a hypothetical model which is shown in chapter 6, we illustrate how chlamydial LPS exerts its spermicidal activity which is via CD14, possibly TLRs, ROS production and finally apoptosis induction.

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Dalai, Farhad N. « Towards an analytic theorization of colour-coded object relations ». Thesis, University of East London, 2001. http://roar.uel.ac.uk/3570/.

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The aim of the thesis is a psychoanalytic and group analytic theorization of racism in general and colourracism in particular in the clinical context in Britain. Following a critical survey of the notion of race, it is suggested that of more significance than race, is the activity of racialization in which the notions of black and white play a central role. The definition of racism proposed is that racism is any use of the idea of race as an organizing principle. Next, explanations of racism are extracted from the theories of Freud, Klein, Fairbairn and Winnicott. This is followed by a critical review of the literature on racism and prejudice found in the main psychoanalytic journals. It is found that the psychoanalytic take on racism is limited in what it can achieve because it is too internalist and individualistic, and so cannot take account of the group phenomenon of racism. The study then gives abbreviated accounts of engagements with racism in the works of Adorno, Kovel, Wolfenstein, Fanon, Rustin and de Zulueta. The thesis now turns its attention from the level of the individual to the level of the group. The group analytic theory of S.H. Foulkes is introduced, in particular his description of the social unconscious. The ideas of Norbert Elias are used to extend group analytic theory to generate a psycho-social theory in which the structures of society are shown to be reproduced in the structure of psyches. The argument continues, that if society is colour-coded, then so is the psyche. Next, the semantic history of the terms black and white in the English language was traced. This included the use of these terms in the Authorized Version of the Bible. It was found that many of the associations with blackness which are taken to be timeless - death, anger, etc. - occur in the last few hundred years. The semantic evidence shows, that before blackness and whiteness could became the servants of racism, they were cathected with negativity and positivity. Following this they were increasingly used as parts-of-names as a way of signalling the value and status of the named. From the 1600's, the confluence of an increasing sense of negativity with the notion of blackness, the naming of non-European "thems' as black, when combined with the labelling of emotions and behaviours progressively designated as disagreeable as black, give credence to the idea that societies and psyches were being divided in colour-coded ways. A general theory of difference was developed based on the work of Matte-Blanco (bilogic), Foulkes (social unconscious), Elias (power-relations) and Winnicott (identity formation). The model of human beings that is generated by this theorization is one in which the forms of psyche are predicated on the forms of society, with the two in a recursive relationship to each other. Components of this model include an alternative model of the unconscious, and a problematizing of the notion of the whole. This theory was applied to the territory of race and racism. The resulting theory of racism is an integration of insights from three domains - the cognitive, the emotional and the sociological. Thus racism can no longer thought of as primarily a result of splitting and projection, but as a complex psycho-social phenomenon that is driven by the pragmatics of the power-relations in the world. Whilst psychological mechanisms play a critical role in this process, they are not elevated as causal agencies. Finally, some indication is given of the resulting modifications required of the practices of psychotherapy - in particular it is argued that the notion of the transference needs to be extended to include the historical relations between groups of people.

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Bhandari, Kalyan. « The role of tourism in the expression of nationalism in Scotland ». Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3570/.

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Tourism like ‘nation’ is a ‘cultural’ concept. In many cases tourism has played a role in the expression of the ‘nation’ and helps solidify the common heritage, cultural kinship, a sense of common identity and belonging. In Scotland, the imagery formed by tourism has helped in the identification of the Scottish nation. This thesis is concerned with the interaction of tourism with the Scottish nation and examines how persistently the touristic heritage of Scotland represents its cultural identity, national image and distinctive characteristics. The main quest was to discover if tourism in Scotland is an expression of nationalism. This was investigated at tourism attractions at three levels - national, regional and personal - with particular reference to the central belt and the southwest region of Scotland. Qualitative research methodology was applied and data were collected through a variety of sources that included a questionnaire survey, interviews, participant observation, field observation and notes, and other unobtrusive and library-based sources. The evidence from this study shows that tourism plays a dominant and meaningful role in the manifestation of Scottish culture and national identity. The findings of this study suggested that the use of images and icons of Scottish cultural heritage in tourism strongly promotes and advances Scottish cultural distinctiveness and identity at all the three levels. At the national level, the presentation of Scottish cultural heritage to tourists in Edinburgh strongly resonates with the ideals of nationalists. At the regional level, the images of Robert the Bruce and Robert Burns in the southwest region in tourism are strong markers of Scottish nationhood. At the personal level, the Scottish heritage of ancestry for genealogical tourists is a strong means to reflect on their identity and cultural roots: for them, touring Scotland is one of the ways to express their ‘national’ feeling and a means to articulate their ‘homeland’ nationalism. These findings reiterated that the touristic heritage of Scotland has elements that closely correspond with the identity of the Scottish nation. Being dominated by heritage attractions, tourism in Scotland is a narrative of its past and the present, through which it mediates the nation, and advances its national sense through recreation, authentication and touristification of its cultural heritage. This study helps us gain a deeper insight into the coherency between the idea of tourism, history, heritage, authenticity, a sense of identity and cultural roots: that can be helpful in understanding the nation from the perspective of tourism. The knowledge from this study can be helpful to the agencies involved in the development and management of tourism and cultural heritage of Scotland.

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Finlay-Smits, Susanna. « Life as engineerable material : an ethnographic study of synthetic biology ». Thesis, London School of Economics and Political Science (University of London), 2016. http://etheses.lse.ac.uk/3570/.

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Synthetic biology is an emerging hybrid discipline that aims to apply an engineering approach to biology, in order to render biology controllable, predictable, and ultimately engineerable. Herein I explore synthetic biology as a project to control life at the molecular level through the lens of an ethnographic study of a newly formed academic synthetic biology research centre. Within this overarching narrative, I tease out two main stories regarding the field. First, I explore the topic of disciplinarity, investigating the work being done to establish synthetic biology as a hybrid discipline. Drawing on the ideas of repertoire, doability, and epistemic cultures, I explore the conflicts and compromises inherent in the attempt to form a hybrid discipline out of biology and engineering. I describe the strategies being employed to bridge this epistemic cultural divide, and the challenges in doing so. Second, I explore the work being done to bring the goals of the discipline to fruition. Synthetic biology’s dream of rendering biology engineerable is rooted in a reductionistic vision of life. This approach to biology raises both practical and conceptual issues. Thus, in exploring this story I address both the practical day-to-day work of synthetic biologists attempting to apply an engineering approach to biology, and the challenges these synthetic biologists face in conceptualising the products of that work. Third, I draw these stories together and show that synthetic biology is one among many disciplines emerging at the intersection of biology and engineering. I suggest that this fertile, if complicated, disciplinary crossroads may be the site of a conceptual shift in the way we ‘do’ and think about biology and ultimately, life.

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Cook, Dee M. « Rich law, poor law : differential response to tax and supplementary benefit fraud ». Thesis, Keele University, 1988. http://eprints.keele.ac.uk/3570/.

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People who (in relation to their personal taxation) defraud the Inland Revenue and people who (in relation to their supplementary benefit payments) defraud the Department of Health and Social Security are similarly engaged in economic crimes which result in loss to the public purse. These crimes provoke differential political, official, judicial and public responses. Differential response to tax and supplementary benefit fraud can neither be explained by reference to qualitative differences in the commission of the illegal acts involved, nor by the crude suggestion that differential regulation of tax and benefit fraud is nothing more than a conspiracy of the rich against the poor. Rather, such differential response derives from the different combinations of legal, economic, social and ideological histories of these two forms of fraud. In this thesis, analysis of these differential and combinatory histories centres on the material conditions and ideological discourses within which differential response is made possible. In addition the vocabularies of motive offered for both the commission and regulation of tax and supplementary benefit fraud are analysed. These analyses together reveal that differential and shifting material and ideological conditions create different opportunities and justifications for both tax and supplementary benefit fraud. At the same time they also enable policy makers continually to change the modes of regulation of both types of crime. The bulk of the thesis is aimed at demonstrating how and why knowledges about taxation and welfare are not immutable but are forever open to deconstruction and challenge.

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Hardie, Rebecca. « (U-Th)/He Thermochronology of the Ottawa Embayment, Eastern Canada : the Temperature-time History of an Ancient, Intracratonic Rift Basin ». Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35070.

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The Ottawa Embayment is a intracratonic rift basin that preserves a unique and eventful history through deep time. Its evolution records opening of the Iapetus Ocean with the break-up of Rodinia, followed by the formation of a continental passive margin, trapping siliciclastic sediments eroded from the adjacent Grenville Province. Samples were collected from a transect across the crystalline rift flank and through the embayment. We investigate the influence of crystallinitiy and non-ideal crystal chapes on He diffusion and resulting zircon (U-Th)/He age with the use of zircon (U-Th)/He thermochronometry, raman spectroscopy and x-ray micro-computed tomography. We then integrate our thermochronology data with regional geology to utilize multi-sample numerical modelling to improve our understanding of the thermal history of the Ottawa Embayment and the evolution of intracratonic rift basins. The works collected within define a comprehensive temperature-time history for the basin and rift flank from the Late-Mesoproterozoic to present day.

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McFadden, Taylor. « Investigating the Effects of Physical Activity Counselling on Depressive Symptoms, Affect and Physical Activity in Female Undergraduate Students with Depression : A Multiple Baseline Single-Subject Design ». Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35270.

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Background: In Canada, women aged 15-24 report the highest rate of depression, an age group which represents a significant proportion of undergraduate students (Hanlon, 2012). Although pharmacology remains the primary treatment for depression, it may not be the most sufficient (Stanton et al., 2014). Physical activity has been demonstrated to have a large and significant antidepressant effect in individuals with depression (Schuch et al., 2016), though what remains challenging is identifying the most effective way to activate this population. Physical Activity Counselling (PAC) has been shown in research to effectively increase levels of physical activity (Fortier et al., 2011). However, the effects of PAC have not been considered in a population of female students with depression specifically. Purpose: To investigate the effects of PAC on depressive symptoms, affect and physical activity in female undergraduate students with depression. Methods: Five female undergraduate students with depression received two months of PAC from a registered Kinesiologist. The study followed a multiple baseline, single-subject design in which measures were taken during four study phases: baseline, intervention, end point and follow-up. Data was collected, including daily objective measures of physical activity, using accelerometers, and self-reported measures of depressive symptoms, positive affect, negative affect and physical activity, using online surveys administered every second day. Results: Visual analyses revealed that depressive symptoms decreased and self-reported physical activity increased from baseline throughout subsequent study phases in all five participants, as hypothesized. Statistical analyses supported these results. Estimated effect sizes of grouped averages indicated that decreases in depressive symptoms from baseline throughout each study phase ranged from small to large, while increases in self-reported physical activity were in the medium to large range. Conclusions: Findings of this study provide initial support for Physical Activity Counselling as a potential strategy to increase physical activity levels and reduce depression among female undergraduate students with depression. Future research is recommended on this important topic.

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Martin, Taylor. « Urban Vulnerability : Bridging Systems and People-Centred Approaches in Dawei, Tanintharyi Region, Myanmar ». Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35370.

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This research discusses urban vulnerability to environmental change in Dawei, Myanmar through the analysis of the exposure and sensitivity of urban systems. The scope of this research attempts to encompass the complexity of multi-scalar relationships between the exposure and sensitivity of urban systems and wider supporting ecological systems to climatic and non-climatic shocks and stresses. Moreover, this research aims to bridge systems and people-centred approaches by considering the existing sensitivity of vulnerable populations living in Dawei through the use of two case studies. Specifically, an urban livelihoods approach was used to consider the entitlements, priorities, and capacities of households to cope with shocks and stress given existing challenges. The analysis of findings have been presented according to nested scales, beginning with the macro-level in the consideration of the exposure of urban socio-ecological systems; the meso-level through the analysis of the differential exposure and sensitivity of two communities living in Dawei in light of access to urban infrastructure and services; and lastly, the micro-level through the analysis of household sensitivity through the application of a livelihoods approach.

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Domingue, Jean-Laurent. « Nurses’ Knowledge, Attitudes and Documentation Practices in a Context of HIV Criminalization : A Secondary Subgroup Analysis of Data from California, Florida, New York, and Texas Nurses ». Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35570.

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Under international legal norms, HIV criminalization is considered to be an overly broad use of criminal law. In the United States, at least 33 states have HIV-specific criminal laws. Data from California, Florida, New York, and Texas nurses provided exemplars from different HIV-related criminal law approaches and the impact of those laws on nurses’ practices. Nurses who cared for patients who expressed fears or concerns about HIV criminalization or patients who had been arrested for HIV-related crimes were more likely to correctly identify the presence or absence of HIV-specific laws in the states where they practised, when compared to nurses who did not care for such patients. Lack of knowledge about HIV-related criminal laws may erode the nurse-patient relationship. Jurisdiction specific education should be created and offered to nurses in order to address this knowledge gap and protect the dignity of people living with HIV.

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Tekieh, Farideh. « Towards the Identification of Candidate Gene(s) for Fusarium Head Blight Resistance on the 7EL Chromosome of Thinopyrum elongatum : Design and Use of Genetic Markers ». Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35670.

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Triticum aestivum (bread wheat), one of the most globally important cereal crops, is vulnerable to fusarium head blight (FHB). The disease is mainly associated with the pathogen Fusarium graminearum and generates yield losses and mycotoxin contaminated grains with low quality. One possible solution to overcome this problem is the production of FHB resistant wheat varieties by crossing with strongly resistant germplasm from either wheat or closely related species. Thinopyrum elongatum is a wild grass that carries genetic resistance to FHB on the long arm of its chromosome 7E (7EL). In the first part of this research project, five Th. elongatum accessions were characterized for their response to F. graminearum infection. In the second part, BC1F4 progeny derived from the cross CS-ph1b × CS-7E(7D) were characterized to better define the 7E fragments introgressed into the 7D chromosome. Progeny were screened with a series of known 7E-specific genetic markers and for their FHB resistance. Among the 43 wheat plants tested, twelve FHB resistant progeny were shown to carry a similar, smaller 7EL introgressed fragment based on genetic marker screening. To characterize further the introgressed 7EL fragments, additional 7EL-specific markers as well as 7DL-specific markers for homoeologous wheat sequences were designed. As neither wheat nor Th. elongatum genomes were fully sequenced at the time, this made the designing procedure challenging; a cross-walking strategy between wheat and Th. elongatum draft genomic sequences was used. Twelve pairs of markers for homoeologous sequence regions of 7EL and 7DL chromosomes plus six individual 7EL- and four 7DL-specific markers were successfully designed. Nine novel 7EL-specific markers were associated with the smallest 7EL fragment carrying FHB resistance. That smallest introgressed 7EL fragment replaced approximately half of the 7DL chromosome, based on the absence of 7DL markers in some progeny. The novel 7EL- and 7DL-specific markers as well as the proposed genetic order for novel and previously designed markers contributed greatly to the characterization of the introgressed 7EL fragments in the 7DL chromosome. Further analysis of progeny from the next generations of these plants and from other families will be required to confirm the results and possibly obtain much smaller 7EL fragments.

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Yandt, Mark. « Characterization Techniques and Optimization Principles for Multi-Junction Solar Cells and Maximum Long Term Performance of CPV Systems ». Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35870.

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Two related bodies of work are presented, both of which aim to further the rapid development of next generation concentrating photovoltaic systems using high efficiency multi junction solar cells. They are complementary since the characterization of commercial devices and the systematic application of design principles for future designs must progress in parallel in order to accelerate iterative improvements. First addressed, is the field characterization of state of the art concentrating photovoltaic systems. Performance modeling and root cause analysis of deviations from the modeling results are critical for bringing reliable high value products to the market. Two complementary tools are presented that facilitate acceleration of the development cycle. The “Dynamic real-time I V Curve Measurement System…” provides a live picture of the current-voltage characteristics of a CPV module. This provides the user with an intuitive understanding of how module performance responds under perturbation. The “Shutter technique for noninvasive individual cell characterization in sealed concentrating photovoltaic modules,” allows the user to probe individual cell characteristics within a sealed module. This facilitates non-invasive characterization of modules that are in situ. Together, these tools were used to diagnose the wide spread failure of epoxy connections between the carrier and the emitter of bypass diodes installed in sealed commercial modules. Next, the optimization principals that are used to choose energy yield maximizing bandgap combinations for multi-junction solar cells are investigated. It is well understood that, due to differences in the solar resource in different geographical locations, this is fundamentally a local optimization problem. However, until now, a robust methodology for determining the influences of geography and atmospheric content on the ideal design point has not been developed. This analysis is presented and the influence of changing environment on the representative spectra that are used to optimize bandgap combinations is demonstrated. Calculations are confirmed with ground measurements in Ottawa, Canada and the global trends are refined for this particular location. Further, as cell designers begin to take advantage of more flexible manufacturing processes, it is critical to know if and how optimization criteria must change for solar cells with more junctions. This analysis is expanded to account for the differences between cells with up to 8 subcell bandgaps. A number of software tools were also developed for the Sunlab during this work. A multi-junction solar cell model calibration tool was developed to determine the parameters that describe each subcell. The tool fits a two diode model to temperature dependent measurements of each subcell and provides the fitting parameters so that the performance of multi-junction solar cells composed of those subcells can be modeled for real world conditions before they are put on-sun. A multi-junction bandgap optimization tool was developed to more quickly and robustly determine the ideal bandgap combinations for a set of input spectra. The optimization process outputs the current results during iteration so that they may be visualized. Finally, software tools that compute annual energy yield for input multi-junction cell parameters were developed. Both a brute force tool that computes energy harvested at each time step, and an accelerated tool that first bins time steps into discrete bins were developed. These tools will continue to be used by members of the Sunlab.

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Al-Bayti, Abdullah. « Vulnerability of Reinforced Concrete Columns to External Blast Loading ». Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35970.

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Reinforced concrete columns are essential elements that are responsible for overall strength and stability of structures. Loss of a column within a frame can cause progressive collapse. While some research has been conducted on blast performance of reinforced columns, primarily under far-field explosions, very limited work exists on the effects of close-in explosions. Dynamic response of concrete columns, in multi storey building, was investigated under close-in blast loads numerically, using FEM software LS-DYNA. A six-storey reinforced concrete building was selected for this purpose. Different standoff distance/charge mass combinations were used to investigate the failure modes of external building columns. Three different charge masses were used; i) backpack bomb having 22.67 kg (50 lbs) of TNT, ii) compact sedan car bomb with 227 kg (500 lbs) of TNT and iii) sedan car bomb with 454 kg (1000 lbs) of TNT. The explosives were placed at different distances relatively close to the structure, triggering different failure modes. Effects of transverse reinforcement and column location (edge versus corner column) were studied under different combinations of charge weight and standoff distance. Column response under dynamic blast load was identified as either local or global. The results show that the failure mode with backpack bombs located at small standoff distance is either local breaching or concrete scabbing. Direct shear failure occurred at column supports when higher charge masses were detonated at close distances. As the standoff distance increased the response changed from breaching or direct shear to diagonal tension and flexure. The column transverse reinforcement played a major role in controlling diagonal shear cracks and promoting flexural response. Hence, the amount and spacing of transverse reinforcement were observed to be important design parameters.

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Scott, Jennifer. « How instruction supportive of self-regulated learning might foster self-efficacy for students with and without learning disabilities during literacy tasks ». Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/35970.

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While self-efficacy (SE) and self-regulated learning (SRL) are key processes that are related to successful literacy performance, these are two areas where students often struggle, particularly students with learning disabilities (LD). Fortunately, research has identified instructional features that can be embedded in classrooms to support SRL. This study built from that research to investigate whether those SRL-supportive instructional features might also support students’ SE while working on literacy tasks in different kinds of classroom placements (inclusive, support, or pull-out). An instrumental qualitative case study design was used to examine the SE of seven intermediate students at different achievement levels, including three students with learning disabilities. Results revealed: (a) similarities across teachers working in different kinds of placements in their use of SRL-supportive instructional features, with some features being implemented with greater frequency and consistency, (b) relationships between environmental conditions and SE, such as the provision of choices, but also (c) the ways in which SE perceptions were mediated by students' perceptions of environmental conditions. Overall, cross-case analyses highlighted the complex, dynamic, and situated nature of SE, and identified ways in which environmental and personal factors interacted in students’ SE attributions. In closing the thesis, these results are considered in the context of previous research, and theoretical, methodological, and practical limitations, contributions and implications are outlined.

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Melton, Darryl C. « Remote sensing and validation of surface currents from HF radar ». Thesis, Monterey, California. Naval Postgraduate School, 1995. http://hdl.handle.net/10945/35170.

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Radial current data from the CODAR HF radar network around Monterey Bay, California, were analyzed for the period of August-December 1994. Previous studies in Monterey Bay used total vector current data. Long-term percent coverage maps showed that coverage decreased radially, vice range, from the site. Through statistical exarnination of radial current data from the Santa Crux and Point Piiios SeaSonde sites and the Moss Landing CODAR site, comparisons along and around the baseline between systems were used to assess system performance. Significant discrepancies were discovered in the directional information from the Point Pinos and Moss Landing sites. Point Pinos' error was approximately 10 counterclockwise and Moss Landing's error was approximately 5 counterclockwise. RMS differences among even the best correlated baseline pairs were approximately 15 cm/s. Data from the baseline was used to select vector currents when the baseline difference was less than 10 cm/s for comparisons with independent nearby moored current observations. This subsampled data did not show significantly better correlation with the moored data than the full data set. Analysis of the radial error estimates provided by the system algorithms determined that no correlation exists between absolute value difference of the radial velocities along the baselines between systems and these built in error estimates

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18

Miller, Christopher Giles. « Micropalaeontology (Conodonta, Ostracoda) across the Ludlow/Pridoli series boundary (Silurian) of Wales and the Welsh Borderland ». Thesis, University of Leicester, 1993. http://hdl.handle.net/2381/35070.

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The ostracod and conodont micropalaeontology of the Silurian Ludlow/Pridoli series boundary is documented from 88 localities across Wales and the Welsh Borderland. Fourteen multielement conodont species (two in open nomenclature), eight unassigned Ozarkodina elements and ten ostracod species (four in open nomenclature) are described from the Upper Whitcliffe and Downton Castle Sandstone formations and their lateral equivalents in Wales and the Welsh Borderland. A septimembrate prionodontid conodont apparatus Coryssognathus dubius (Rhodes, 1953) is reconstructed from discrete elements. Original calcareous valves of the ostracod Frostiella groenvalliana and moulds of open and partially open ostracod carapaces are described for the first time from the Welsh Basin. The Upper Whitcliffe Formation and its lateral equivalents are characterised by the ostracod Calcaribeyrichia torosa and the conodonts Ozarkodina confluens, Ozarkodina excavata, Panderodus serratus and Coryssognathus dubius. The Downton Castle Sandstone Formation and its lateral equivalents are characterised by the ostracods F. groenvalliana, Londinia arisaigensis, Londinia fissurata and Nodibeyrichia verrucosa. Conodont trends across the shelf area of the Welsh Borderland reflect an increasingly turbulent environment towards the top of the Ludlow Series. The sudden ostracod faunal change at the base of the Downton Castle Sandstone at Ludlow (shelf) contrasts with a gradual change at Long Mountain (basin) and parallels shelf-basin palynofacies changes. Variations in ostracod frequency, faunal composition and carapace preservation in the Downton Castle Sandstone Formation at Ludlow coincide with minor lithofacies variations. Local variations in the frequency of ostracods and land plant spores may be related to proximal channels delivering sediment off an irregularly prograding shoreline. Ostracod faunas correlate the base of the Downton Castle Sandstone across the Welsh Borderland to localities in E central Wales where bone beds are absent. Combined conodont and ostracod evidence suggests that the base of the Pridoli Series is concurrent with the base of the Downton Castle Sandstone Formation in Britain.

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Kuhlman, Philip Alan. « Characterisation of the actin-binding site of α-actinin ». Thesis, University of Leicester, 1993. http://hdl.handle.net/2381/35270.

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The alpha-actinin residues involved in the interaction of chicken smooth muscle alpha-actinin with F-actin were defined by co-sedimentation. Residues 120 to 140 of alpha-actinin were identified as essential with residues 141 to 159 and 1 to 107 contributing to the interaction. Temperature dependent binding and the lack of inhibition by high salt concentrations implicated hydrophobic interactions in the binding mechanism. Further characterisation of the binding interaction using stopped-flow techniques determined a K for the interaction of 0.82 muM at 15°C and 2.38 muM at 25°C. These techniques distinguished between the initial binding event and the subsequent bundling of the actin filaments. The consequences of bundling on the binding equilibrium are discussed. The role of the actin N-terminus as the initial docking site for alpha-actinin has been investigated using a peptide corresponding to this region of actin. The lack of any detectable interaction suggests that this region of actin does not interact with alpha-actinin. This is consistent with the mapping of the binding site for alpha-actinin on the opposite side to the N-terminus of the actin molecule. In addition to studying the binding mechanism the structure of the alpha-actinin actin-binding domain (ABD) was investigated. This domain of alpha-actinin is proposed to consist of two smaller sub-domains. Attempts to crystallise the ABD of alpha-actinin have failed due to the amphipathic nature of the domain. The alpha-actinin interaction with F-actin is proposed to be mediated by both electrostatic and hydrophobic forces. The interaction site is composed of distinct sites within the primary sequence. This model is similar to those proposed for the interaction of DNase I, myosin and gelsolin segment 1 with actin.

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Thomas, Daniel G. « The self-interaction of myosin ». Thesis, University of Leicester, 1992. http://hdl.handle.net/2381/35170.

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The first event in thick filament formation must be the interaction of one myosin monomer with another to give a dimer. The energetics of the parallel apposition of the rod portion of myosin were first considered by McLachlan and Karn (Nature 299: 226-231, 1982; J. Mol. Biol. 164: 605-626, 1983). They applied a simple 'point scoring' algorithm to the periodic charge distribution of the myosin rod and suggested that there are peaks in interaction energy when the stagger between parallel rods is close to 14.3 and 43nm. We have modelled the assembly process on a more detailed basis in an attempt to understand the factors governing the structure of the thick filament. We have taken into account both the hydrodynamic and electrostatic properties of myosin. It is likely that the final state of parallel apposition of the monomers is reached via intermediate states. We identify as a likely intermediate a structure in which two monomers are bound at a single point contact to form an extended dimer, and have computed the likelihoods of formation and the stabilities of different forms of this structure. We have also computed the energetics of the pathways leading to the more stable parallel dimer. Our results suggest that selectivity for a 14.3 nm axial stagger is inherent in the pathway for dimerisation but that it is a consequence of the kinetics rather than the energetics of the assembly process. We have identified rat cardiac myosin at minimal ionic strength as a system in which later steps in the assembly process are blocked; small myosin oligomers become stable structures rather than transient intermediates and so can be trapped and characterised. The structures found are in both qualitative and quantitative agreement with the computational predictions.

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Menon, Viju S. (Viju Sreedhara). « A constraint-based systems approach to line yield improvement in semiconductor wafer fabrication ». Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/35970.

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Moeckel, Curtis William. « Probabilistic turbine blade thermal analysis of manufacturing variability and toleranced designs ». Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35570.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2006.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 73-75).
Manufacturing variability is likely the primary cause of a large scatter in the life of gas turbine hot-section components. This research deals with schemes to improve robustness through tolerancing input parameters in ranges of the distributions which make non-conformances more likely. The need for probabilistic analysis to investigate this problem is substantiated due to differences which arise when input parameters vary at different levels, for example the engine-to-engine and blade-to-blade level. Specifically, the importance of blade-to-blade level input parameters relative to engine-to-engine level input parameters becomes increasingly important for larger numbers of blades in a row. A framework for calculating the potential number of prevented non-conformances and the corresponding cost savings associated with various tolerancing schemes is presented. Specifically this research investigates manufacturing variability and its effect on first-stage turbine blades through the use of a parametric CAD model, automated CAD regeneration software, and a parametric finite element thermal model. Probabilistic analysis is performed using Monte Carlo simulation on both the finite element model as well as response surfaces built from the finite element model.
(cont.) Blade-to-blade cooling flow variability, especially as a result of film-hole diameter variability in critical locations is identified as the most likely candidate for parameter tolerancing. More promising is a combined two-factor tolerancing scheme which additionally tolerances gas path temperature.
by Curtis William Moeckel.
S.M.

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DiPerna, Daniel T. « Sound scattering by cylinders of noncircular cross section ». Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/35370.

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Giam, Louise R. « Gallium Nitride (GaN) quantum dot layer formation ». Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35070.

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Inman, Samuel Walker. « Development of a high throughput 3D perfused liver tissue bioreactor ». Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35670.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
Includes bibliographical references (p. 125-127).
This thesis describes the development of a device designed for culturing liver tissue in a 3D perfused environment. Cells form tissue inside miniature channels of a scaffold, and the tissue is perfused with culture medium to create a culture microenvironment that has previously been described by the Griffith lab. In order to support this microenvironment, the reactor needs a pumping system, reservoirs and a controller. Previously, these have all been stand-alone components. This work focuses on the development of a new, integrated culture system. This system integrates 12 reactor microenvironments, reservoirs and pumping systems onto a single plate with a configuration modeled after standard multi-well plates. Each of the 12 bioreactor units utilize pneumatic pumps driven by a single external controller. This design offers substantial advantages over previous systems as it is far more user-friendly and can be used in a higher throughput capacity. The thesis describes the design and fabrication of the reactor and controller, including several models that were used during the development process. It also offers mechanical and biological characterizations of the device.
by Samuel Walker Inman.
S.M.

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Castelino, Judith Andrea. « Estimating mobility values from electroluminescence measurements on organic polymers ». Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/35470.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.
Includes bibliographical references (leaves 73-74).
by Judith Andrea Castelino.
M.Eng.

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Dunn, James. « High resolution X-ray spectroscopy of laboratory sources ». Thesis, University of Leicester, 1990. http://hdl.handle.net/2381/35870.

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A detailed programme of research is presented to design, build and operate a high resolution h?hz5000 curved crystal Johann-type x-ray spectrometer for the waveband below 13A. The spectrometer is used to observe line emission features from different laboratory x-ray sources. Characteristics of the Johann geometry are described with emphasis given to the properties of sensitivity, dispersion, resolving power and waveband. The tolerance of the instrumental parameters is defined for successful high spectral resolution operation. The key feature of the spectrometer is the unique crystal bending device which can generate a high quality cylindrical curvature of radius R=150?5000mm. The crystal focusing alignment and testing procedures are evaluated. Choice of crystals suitable for the observation programme is discussed together with analysis techniques for interpretation of the x-ray spectral line profiles. The instrument is optimised for time-integrated and time-resolved ion temperature measurements of UKAELA DITE Tokamak at the Culham Fusion Laboratory. X-ray line emission results from medium Z He-like and H-like impurity ions are presented for different plasma conditions. Density sensitive He-like and Li-like Aluminium ion satellite emission features are studied for intense transient laser produced plasmas at the Central Laser Facility, SERC Rutherford Appleton Laboratory. The peak plasma electron density of 0.1 time solid density is estimated from these line intensity ratios and is in good agreement with Stark line width measurements. X-ray emission from beam-foil interactions is observed on the Folded Tandem accelerator of the Nuclear Physics Department, Oxford University. The proposed improvement in the intrinsic spectral line broadening due to the accelerator is investigated by high resolution axial beam measurements of the He-like Silicon and H-like Neon n=2 transitions. The Lyman-a intensity ?-ratio and wavelength separation ?hFS is studied for the fine-structure of Hydrogenic Neon, Magnesium, Aluminium and Silicon. The fine-structure separation is compared with the Dirac theory and other experimental data, while the possible mechanisms giving rise to the non-statistical value of the ?-ratio are analysed.

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Byun, Jae-Woong. « New theoretical foreign direct investment (FDI) model : the Korean FDI in the European Union as a case study ». Thesis, University of Leicester, 1995. http://hdl.handle.net/2381/35470.

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Sousek, Nicholas D. « Enhancing grain marketing decisions : farm breakeven analysis and grain sales management ». Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/35770.

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Master of Agribusiness
Department of Agricultural Economics
Daniel M. O'Brien
In recent years, the price volatility in agricultural commodity prices, as well as agricultural input costs, has drastically increased. Today’s famer is faced with difficult decisions concerning when to market their crop, as well as when to secure various inputs. An increase in information availability, coupled with increasing price fluctuations, can make these decisions even more difficult for producers. Although seasonal trends, forecasts, and technical market analysis can be helpful, market efficiency prevents accurate prediction of agricultural prices. Because marketing decisions can be difficult to make, the easiest decision for a producer to make is to not make one at all. However, failure to make sound risk management decisions can be extremely costly to a producer. There are two primary factors that impact a producer’s bottom line: cost of production and grain marketing decisions. Each producer has their own unique cost of production that changes throughout the year. Variable input costs can be volatile within a single growing year, and often the need for certain inputs changes. Marketing decisions and timing can be an even bigger factor in a producer’s gain or loss. Since price prediction is impossible, a producer’s time may be better spent focusing on information they can control. The purpose of this thesis was to test and evaluate a cost of production, crop insurance, and grain marketing calculator with a group of corn and soybean producers in Southeast Nebraska. It is hypothesized that providing customers with a multifaceted, integrated farm management and marketing decision making tool should help them be able to make more profitable risk management and marketing decisions. By knowing how factors as changing expenses impact cost of production and how grain sales impact revenues and profitability per acre, it is hypothesized that users will make more profitable farm management and marketing decisions. In October and November of 2014, twenty corn and soybean farmers were presented with the Grain Marketing Calculator. Grain sales in the 2014 and 2015 crop years were to be entered into the calculator by participating producers as they make their grain sales. Annual production history (APH), revenue protection insurance information, actual or expected yields, and total acres of each crop were entered into the calculator during the initial producer calculator rollout. Generalized costs were entered into the calculator prior to the producer rollouts. Participants were able to change the generalized costs to their actual costs if they chose to do so. Data were gathered from the participants using the Grain Marketing Calculator in March of 2015. Participants weighted average futures sales, weighted average cash sales, percent of APH sold, and percent of total production sold were collected. In March of 2015, the same information from another group of producers who did not use the Grain Marketing Calculator was collected. The two groups average results were compared to each other and regression analyses were done to determine statistical significance of the impact on the test groups’ results. At the end of the experiment, feedback was gathered from participants and improvements were suggested.

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Angeloni, Luiz Mario. « Polímeros obtidos a partir do biodiesel epoxidado dosóleos de oliva e soja : preparação e caracterização química e físico-química ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/35070.

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Este trabalho apresenta a obtenção de polímeros sintetizados a partir do biodiesel epoxidado do óleo de oliva (EEO) e soja (EES) utilizando anidrido ftálico (PH) como agente reticulante e 2-metil imidazol (2MI) como iniciador. Os materiais utilizados no processo de polimerização foram analisados por ressonância magnética nuclear de hidrogênio (RMN ¹H). A síntese foi realizada variando as proporções molares de biodiesel epoxidado (EEO ou EES) e anidrido ftálico, mantendo a fração molar do iniciador 2MI constante. Os polímeros foram caracterizados por cromatografia de permeação em gel (GPC), ressonância magnética nuclear de hidrogênio (RMN ¹H), espectroscopia na região do infravermelho com transformada de Fourier (FTIR), calorimetria exploratória diferencial (DSC) e análise termogravimétrica (TGA). Os polímeros derivados do óleo de soja apresentaram insolubilidade em clorofórmio, acetona, água, tetrahidrofurano, metanol e dimetilsulfóxido, impossibilitando as análises por GPC e RMN 1H. As massas molares dos polímeros derivados do óleo de oliva foram determinadas por GPC, apresentando valor máximo de 40.000 g.mol-1, e suas estruturas químicas avaliadas por RMN 1H. O estudo cinético da reação de polimerização foi realizado via DSC, determinando parâmetros cinéticos, tais como a energia de ativação, fator pré-exponencial e constante de velocidade, e termodinâmicos, como entalpia de formação (HTotal). Utilizou-se FTIR para caracterizar os grupos funcionais e TGA para avaliar o processo de termodegradação e realizar um novo tipo de tratamento térmico dos materiais obtidos.
This study presents polymers synthesized by using epoxidized biodiesel from olive (EEO) and soybean (ESS) oils, using phthalic anhydride (PH) as crosslinker and 2-methyl imidazole (2MI) as initiator. The materials used in the polymerization reactions were analyzed by nuclear magnetic resonance of hydrogen (¹H NMR). The synthesis was performed by varying the molar ratios of epoxidized biodiesel (EEO or ESS) and phthalic anhydride, keeping the mole fraction of initiator 2MI constant. The polymers were characterized by gel permeation chromatography (GPC), nuclear magnetic resonance of hydrogen (¹H NMR), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The polymers obtained from soybean oil showed insolubility in chloroform, acetone, water, tetrahydrofuran, methanol and dimethyl sulfoxide, precluding the analysis by GPC and ¹H NMR. The molar mass of polymers from olive oil was determined by GPC, with a maximum value of approximately 40.000 g.mol-1, and the chemical structures evaluated by ¹H NMR. The kinetic study of the polymerization reaction was carried out by DSC, determining kinetic parameters, such as the activation energy, pre-exponential factor and velocity rate constant, and thermodynamic as enthalpy of formation (HTotal). The Fourier transform infrared spectroscopy (FTIR) was used to characterize the functional groups. The thermogravimetric analysis (TGA) was used to evaluate the process of thermo-degradation process and additionally a new treat thermally the obtained polymeric materials.

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Bom, Nicolau Molina. « Propriedades físico-químicas de filmes finos de Al2O3 depositados por sputtering sobre Ge ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/35170.

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Nesta dissertação, foram investigadas as propriedades físico-químicas de filmes finos de óxido de alumínio (Al2O3). O Al2O3 foi depositado sobre substratos germânio (Ge) e silício (Si) por magnetron sputtering reativo, utilizando uma fonte DC pulsada, visando a produzir camadas com baixas quantidades de OH e H2O, em comparação àquelas produzidas pelo processo de deposição por camadas atômicas (ALD). Dados obtidos por espectroscopia de fotoelétrons (XPS) e perfis de concentração obtidos por reações nucleares ressonantes (NRP) evidenciaram a formação de uma camada de GeO2 sobre os substratos de Ge, durante o processo de deposição. Quando as amostras foram submetidas a tratamentos térmicos em atmosferas de Ar e forming gas, foi verificada a redução desse óxido. Foi observado que a camada de transição remanescente na interface é constituída essencialmente de germanatos de alumínio. O efeito dos principais contaminantes introduzidos pela técnica de ALD (água e/ou grupos hidroxila) foi investigado por meio de tratamentos térmicos em atmosferas de oxigênio (O2) e vapor d’água. Dados de NRP mostraram que a incorporação de O aumenta com a temperatura de tratamento e depende do gás empregado. Também observou-se que o O proveniente da fase gasosa interage fortemente com o substrato semicondutor de Ge, efeito não observado nas amostras de Si. Análises com técnicas por espalhamento de íons evidenciaram um aumento na concentração de Ge dentro da camada de Al2O3 e na superfície das amostras, efeito associado à oxidação do substrato de Ge. Essas observações podem ser explicadas pela dessorção de GeO resultante de reações químicas que ocorrem na interface dielétrico/substrato.
In this dissertation, physico-chemical properties of aluminum oxide (Al2O3) thin films were investigated. Al2O3 was deposited by pulsed DC reactive magnetron sputter on Germanium (Ge) and Silicon (Si) substrates aiming at producing layers with reduced OH and H2O content, in comparison with those produced by the atomic layer deposition (ALD) process. Photoelectron spectroscopy (XPS) and nuclear reaction profiling (NRP) evidenced the formation of a GeO2 layer during deposition of thin film. Thermal annealing in Ar and forming gas atmospheres reduced the amount of this oxide layer. The remaining transition layer consisted essentially of aluminum germanates. The effects of the main contaminants introduced by ALD techniques (water and/or hydroxyl groups) could be probed by exposing as-deposited samples to water vapor or oxygen (O2) atmospheres. NRP revealed that O incorporation increases with the thermal annealing temperature and also depends on the employed atmosphere. We also found that O from the gas phase strongly interacts with the Ge semiconductor substrate, effect not observed in Si samples. Ion scattering analyses evidenced an increase of Ge concentration throughout the Al2O3 dielectric layer and on the sample surface, associated with the oxidation of the Ge substrate. These findings are explained by GeO desorption resulting from chemical reactions occurring at the dielectric/Ge interface.

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Namburu, Visala. « Speech Coder using Line Spectral Frequencies of Cascaded Second Order Predictors ». Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35670.

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A major objective in speech coding is to represent speech with as few bits as possible. Usual transmission parameters include auto regressive parameters, pitch parameters, excitation signals and excitation gains. The pitch predictor makes these coders sensitive to channel errors. Aiming for robustness to channel errors, we do not use pitch prediction and compensate for its lack with a better representation of the excitation signal. We propose a new speech coding approach, Vector Sum Excited Cascaded Linear Prediction (VSECLP), based on code excited linear prediction. We implement forward linear prediction using five cascaded second order sections - parameterized in terms of line spectral frequency - in place of the conventional tenth order filter. The line spectral frequency parameters estimated by the Direct Line Spectral Frequency (DLSF) adaptation algorithm are closer to the true values than those estimated by the Cascaded Recursive Least Squares - Subsection algorithm. A simplified version of DLSF is proposed to further reduce computational complexity. Split vector quantization is used to quantize the line spectral frequency parameters and vector sum codebooks to quantize the excitation signals. The effect on reconstructed speech quality and transmission rate, of an increased number of bits and differently split combinations, is analyzed by testing VSECLP on the TIMIT database. The quantization of the excitation vectors using the discrete cosine transform resulted in segmental signal to noise ratio of 4 dB at 20.95 kbps, whereas the same quality was obtained at 9.6 kbps using vector sum codebooks.
Master of Science

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Wiseman, P. Eric. « Soil Carbon Dioxide Efflux Across Four Age Classes Of Plantation Loblolly Pine (Pinus taeda L.)On The Virginia Piedmont ». Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/35770.

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Soil carbon dioxide efflux resulting from microbial and root respiration is a major component of the forest carbon cycle. We undertook this investigation to better understand the nature of soil carbon dioxide efflux of plantation loblolly pine, an important ecological and economical resource in the southeastern United States. Specifically, we hoped to learn how soil carbon dioxide efflux differs both spatially and temporally for four age classes of plantation loblolly pine on the Virginia piedmont. During a 12-month period, soil carbon dioxide efflux was repeatedly measured for four age classes of plantation loblolly pine using a dynamic, closed-chamber infrared gas analyzer. The age classes examined were 1- to 2-year-old, 4- to 6-year-old, 8- to 12-year-old, and 20- to 25-year-old stands. Mean soil carbon dioxide efflux rates measured during the 12-month study were 1.72, 2.58, 2.84, and 2.90 micromole/sq m/s for 1- to 2-year-old, 4- to 6-year-old, 8- to 12-year-old, and 20- to 25-year-old stands, respectively. Stand age had a significant effect on efflux rate during 10 of the 12 monthly sampling sessions. Additionally, mean efflux rates were consistently higher near the tree and a significant positional difference was detected during 8 of the 12 monthly sampling sessions. Mean soil carbon dioxide efflux rates, by position, for the 12-month study were 2.72 and 2.28 micromole/sq m/s for the near and away measurement positions, respectively. Based on monthly mean soil carbon dioxide efflux rates, annual carbon losses were estimated at 651, 976, 1074, and 1082 g C/sq m/yr for 1- to 2-year-old, 4- to 6-year-old, 8- to 12-year-old, and 20- to 25-year-old stands, respectively. Regression analysis was used to examine the influence of soil and climatic factors on seasonal changes in soil carbon dioxide efflux. The most influential factors affecting soil carbon dioxide efflux during the 12-month study were soil temperature, soil moisture, stand age, and measurement position. We believe respiring roots significantly influence soil carbon dioxide efflux of plantation loblolly pine and account for differences observed between stands of different ages as well as spatial differences observed within a given stand.
Master of Science

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Mannon, Adria G. « Preventing Oxidation of Dairy Powders Using Oxygen Removal Packaging ». Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/35970.

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Three types of dried milk (whole, nonfat, and buttermilk) were packaged in a modified atmosphere with a novel palladium-based oxygen removing catalyst and stored for eight weeks at 50Â°C. Powders stored in air with no catalyst and powders stored with the catalyst in an atmosphere modified to contain 5.7% hydrogen in nitrogen were evaluated by instrumental, chemical, and sensory methods. Hexanal concentrations were measured weekly using solid phase microextraction (SPME) and gas chromatography (GC) to compare the degrees of oxidation in the powders stored with the catalyst to those stored without it. Color changes were also monitored weekly using Hunterâ s L-, a-, and b-values. At the end of the eight-week period, a paired comparison sensory test was used to ascertain if the catalyst had an effect on odor. Anisidine values were also measured at this point to determine levels of oxidation in the powders. No significant difference was found in levels of oxidation between samples packaged with and without the catalyst in the modified atmosphere. At the end of eight weeks, the average hexanal concentration in the whole milk powder stored with the oxygen scavenger was 1.19 Â± 0.20 ppm, while the average hexanal concentration in the air-packed whole milk powder was 1.06 Â± 0.08 ppm. The average hexanal concentrations for the buttermilk stored with the catalyst and without were 0.84 Â± 0.18 and 0.79 Â± 0.15 ppm, respectively. In the nonfat milk powder, the sample stored with the catalyst had an average hexanal concentration of 0.91 Â± 0.14 ppm and the sample stored in air without the catalyst had an average hexanal concentration of 0.83 Â±0.20 ppm. Difference testing by volunteer sensory panelists also revealed no significant differences. It was expected that the milk powders stored with the catalyst in the modified atmosphere would have lower levels of oxidation and off-odors at the end of the eight weeks. However, the treatment ultimately resulted in no chemical or sensory differences. Thus, the catalyst proved ineffective in the given conditions. This could be due to a loss of the hydrogen required for the catalyst to function as time progressed or a lack of significant oxidation under the conditions employed.
Master of Science in Life Sciences

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Song, Xiaolan. « Modeling of Thermoplastic Composite Filament Winding ». Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/35370.

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Thermoplastic composite filament winding is an on-line consolidation process, where the composite experiences a complex temperature history and undergoes a number of temperature history affected microstructural changes that influence the structure's subsequent properties. These changes include melting, crystallization, void formation, degradation and consolidation. In the present study, models of the thermoplastic filament winding process were developed to identify and understand the relationships between process variables and the structure quality. These include models that describe the heat transfer, consolidation and crystallization processes that occur during fabrication of a filament wound composites structure.

A comprehensive thermal model of the thermoplastic filament winding process was developed to calculate the temperature profiles in the composite substrate and the towpreg temperature before entering the nippoint. A two-dimensional finite element heat transfer analysis for the composite-mandrel assembly was formulated in the polar coordinate system, which facilitates the description of the geometry and the boundary conditions. A four-node 'sector element' was used to describe the domain of interest. Sector elements were selected to give a better representation of the curved boundary shape which should improve accuracy with fewer elements compared to a finite element solution in the Cartesian-coordinate system. Hence the computational cost will be reduced. The second thermal analysis was a two-dimensional, Cartesian coordinate, finite element model of the towpreg as it enters the nippoint. The results show that the calculated temperature distribution in the composite substrate compared well with temperature data measured during winding and consolidation. The analysis also agrees with the experimental observation that the melt region is formed on the surface of the incoming towpreg in the nippoint and not on the substrate.

Incorporated with the heat transfer analysis were the consolidation and crystallization models. These models were used to calculate the degree of interply bonding and the crystallinity achieved during composite manufacture. Bonding and crystallinity developments during the winding process were investigated using the model. It is concluded that lower winding speed, higher hot-air heater nozzle temperature, and higher substrate preheating temperature yield higher nippoint temperature, better consolidation and a higher degree of crystallization. Complete consolidation and higher matrix crystallization will result in higher interlaminar strength of the wound composite structure.

Master of Science

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Kamat, Vineet Rajendra. « Enabling 3D Visualization of Simulated Construction Operations ». Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/35470.

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Simulation modeling and visualization can substantially help in designing complex construction operations and in making optimal decisions where traditional methods prove ineffective or are unfeasible. However, there has been limited use of simulation in planning construction operations due to the unavailability of appropriate visual communication tools that can provide users with a more realistic and comprehensible feedback from simulation analyses. Visualizing simulated construction operations in 3D can significantly help in establishing the credibility of simulation models. In addition, 3D visualization can provide valuable insight into the subtleties of construction operations that are otherwise non-quantifiable and presentable. New software development technologies emerge at incredible rates that allow engineers and scientists to create novel, domain-specific applications. This study capitalized on a computer graphics technology based on the concept of the "Scene Graph" to design and implement a general-purpose 3D Visualization System that is Simulation and CAD-software independent. This system, the "Dynamic Construction Visualizer", enables realistic visualization of modeled construction operations and the resulting products in 3D and can be used in conjunction with a wide variety of simulation tools. This thesis describes the "Dynamic Construction Visualizer" as well as the "Scene Graph" architecture and the Frame Updating algorithms used in its design.
Master of Science

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Vittes, Fernando J. « Optimizing The Performance Of A Chip Shooter Machine ». Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/35070.

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Process planning is an important and integral part of operating a printed circuit board (PCB) assembly system effectively. The focus of this research is to develop a new solution approach to determine the component placement sequence and feeder assignment for a turret style Chip Shooter machine often used in PCB assembly systems. This solution approach can be integrated into a process planning system to reduce assembly time and improve productivity. The Chip Shooter machine consists of three primary mechanisms: the turret head, a moving table, and the feeder carriage. These mechanisms move simultaneously in a cyclic manner to mount the components on the PCB. The mechanism with the longest movement time determines the placement time of a component. Therefore, the placement sequence of the components and the arrangement of the feeders in the feeder carriage directly affect the time required to mount all the components on a PCB. A placement time estimator function that accounts for the functional characteristic of the Chip Shooter machine is developed and is used to evaluate the performance of the solution approach presented in this research. The solution approach consists of a construction algorithm that uses a set of knowledge-based rules to construct an initial placement sequence and feeder assignment, and an improvement procedure to improve the initial solution. A case study is presented to validate the proposed solution approach. A Fuji CP4-3 machine and actual PCB data are used to test the performance of the proposed solution approach for different machine setup scenarios. The solutions obtained using the proposed solution approach are compared to those obtained using state of the art PCB assembly process optimization software. For all PCBs in the case study, the proposed solution approach yielded lower placement times than the commercial software, thus generating additional valuable production capacity.
Master of Science

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Garr, Andrew Lee. « Analysis of flour market segments : a study of how specialty products affect volume, sales dollars, and margin dollars ». Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35270.

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Master of Agribusiness
Department of Agricultural Economics
Andrew P. Barkley
The objectives of this thesis is to use regression models and market trends to determine whether the changing product mix of Ardent Mills has an impact on volume, sales dollars, and margin dollars. The results will be used to build a market analysis of Ardent Mills’ product mix strategy. Flour milling is a highly competitive industry. Ardent Mills is constantly looking to increase profits and become more valuable to its customers. Specialty products have created a new opportunity, but the opportunity costs must also be considered. Determining what new products to develop, where to manufacture them, and whether to create new capacity or convert existing capacity are difficult decisions that must be made. The data used in this thesis were collected from Ardent Mills’ sales records from June 1, 2014 through December 31, 2016. Type of product, sales volume, sales dollars, and margin dollars were collected for each month to be analyzed. The study determined that increasing the volume of whole wheat flour sales decreases white flour volume, total flour volume, white flour sales dollars, and total flour sales dollars. Increasing the volume of UltraGrain increases white flour sales dollars and total flour sales dollars. Increasing the volume of wheat-based specialty products increases the volume of white flour and the volume of total flour. As the demand for UltraGrain and wheat-based specialty products increases, the demand for white flour increases as well. Decreasing wheat prices have allowed for additional margin to be captured.

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Craig, Julie. « Economic feasibility of growing hops in Nebraska ». Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35370.

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Master of Agribusiness
Department of Agricultural Economics
Vincent R. Amanor-Boadu
Nationwide, the craft brew industry has enjoyed massive growth. Hops are an important ingredient in craft brew beer and rapid growth of this industry has created many opportunities to grow hops. Currently, hops production is concentrated in the Pacific Northwest. That is beginning to change with new hops acres being planted every year across the country. The study looks at how economically feasible it is to plant hops in Nebraska. Is there enough local demand? Finally, given that Nebraska’s weather is dramatically different than the Pacific Northwest, can hops flourish there? The research begins by assessing all costs associated with a starting a three acre hops operation. Estimated yield and income is projected for ten years to establish cash flow. Instances of hail, wind and tornados for Clay County Nebraska for the years 2006-2016 were calculated to determine a probability of those weather events occurring. The probability was then used to determine the effect it could have on yield of hops per year. In addition to cost of production, the study also documented the growth of Nebraska’s craft brew industry to establish demand for locally grown hops. The researched concluded that if production stayed constant and our discount rate at 5%, assuming prices remain where they are or higher, then it is economically feasible to grow hops in Nebraska. Wind, hail and tornadoes do pose a threat in the Midwest but their effect on yield is not enough to deter someone from planting hops there. Access to reliable capital to begin and sustain a hops operation appears to have a greater impact. In addition, Nebraska’s craft brew industry continues to expand rapidly suggesting a strong market for locally grown hops. This information is important for anyone who is considering planting a commercial hops yard. Given how expensive the start-up costs are and how labor intensive the crop is, this research can provide guidance to those seeking to add hops production to their new or existing farming operation.

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Zhang, Man. « Design, synthesis, and evaluation of bioactive molecules ; Chiral polyvinylpyrrolidones supported Cu/Au nanoclusters catalyzed cyclization of 5-substituted nona-1,8-dien-5-ols ». Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35470.

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Doctor of Philosophy
Department of Chemistry
Duy H. Hua
Small molecules are of great importance in drug discovery currently. The first three chapters discussed the design, synthesis and bio-evaluation of three different classes of small molecules and exploration of their biological targets. Triacsin C analogs were designed as long chain fatty acyl-CoA synthetase (ACSL) inhibitors for attenuating ischemia and reperfusion (I/R) injury. Oxadiazole derivatives were designed as T-type calcium channel inhibitors, which have potential application in the treatment of seizure and epilepsy. Tricyclic pyrone derivatives were reported as anti-Alzheimer lead compounds in previous research done by the Hua group. TP70 and CP2 were synthesized to explore their pharmacokinetics properties. Chapter 4 described chiral-substituted poly-N-vinylpyrrolidones (CSPVP) supported Cu/Au nanoclusters mediation of cyclization reaction of 5-substituted nona-1,8-dien-5-ols. A five-member cyclized lactone possessing a stereogenic tetrasubstituted carbon center was formed in a one-step Cu/Au nanoclusters-hydrogen peroxide oxidation reaction. This developed a novel and simple method to synthesize tetrasubstituted carbon stereogenic center. Drawbacks of the method in my initial study were low reaction yield and moderate enantioselectivity. The chemical yield and enantioselectivity have been significantly improved by introducing bulkier substitution in C3 and C4 positions of CSPVP according to the updates of ongoing research.

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Gajula, Hyma. « Effect of wheat bran on gluten network formation as studied through dough development, dough rheology and bread microstructure ». Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35570.

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Doctor of Philosophy
Department of Grain Science and Industry
Hulya Dogan
Jon M. Faubion
The overall hypothesis underlying this study is that the nature and extent of bran interactions with the gluten protein matrix play a dominant role in both 'in-process' dough and final product quality of whole grain baked goods. Therefore, the purposeful manipulation of those interactions should be able to minimize adverse processing or product characteristics resulting from bran inclusion/presence. The approach we took was to study the effects of bran milled to different particle sizes on dough development during and after dough mixing using fundamental rheology combined with traditional cereal chemistry approaches and x-ray microtomography (XMT). The research outcomes were used to create a better picture of how the bran is effecting the dough development and to suggest strategies that allow for the control of that effect. Study-I focused on characterization of the chemical properties, empirical rheological properties and baking performance of flours and dough with different bran contents from different sources. The development of dough microstructure and the resulting crumb texture in the presence of different bran were studied using XMT. HRW and SW bran additions resulted in higher water absorptions (WA) irrespective of the flour type and bran source. Fine bran caused slightly higher WA followed by coarse and as is bran. Both HRW and SW bran decreased the dough stability of HRW flour, while it improved the stability of SW flour doughs. Macro and microstructure of baked products were significantly affected both bran type and addition level. HRW bran added to HRW flour resulted in 8-23% decrease in loaf volume while SW bran added at the same level caused 3-11% decrease. XMT indicated that bran decreased the total number of air cells significantly. SW flour resulted in harder crumb texture than that of HRW flour breads. Overall, SW bran had less detrimental effects on mixing and baking performance of HRW flour. Study-II focused on specific bran particle size and composition on small and large deformation behavior of strong and weak flour doughs. Small deformation behavior was characterized using frequency and temperature sweep tests, while the large deformation behavior was studied using creep–recovery and uniaxial extensional testing. The results revealed that the rheological behavior of bran-enriched doughs depend on type of base flour, bran type, bran replacement level (0, 5, 10%), and the dough development protocol. Weak flour doughs benefited from inclusion of bran as inherently low peak height and stability of these doughs improved in the presence of bran. Temperature sweeps indicated a slight decrease in Gʹ and G" until around 55-60°C. In the same temperature range, presence of bran increased the moduli of composite four compared to that of the control flours. Creep compliance parameters indicated that both bran source and bran replacement had significant effect on maximum compliance (J[subscript max]) and elastic compliance (J[subscript e]). Finally, the bran type affected uniaxial extensional properties, maximum resistance (R[subscript max]) and elasticity (E), significantly independent from the type of base flour.

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42

Yousuf, Tariq bin. « Sustainability and replication of community-based composting : a case study of Bangladesh ». Thesis, Loughborough University, 2005. https://dspace.lboro.ac.uk/2134/35070.

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Solid waste management is a key concern for the local authorities in developing countries. The continued generation of solid waste, increasing waste management costs and scarcity of landfill space have compounded solid waste problems to a serious stage. Local authorities struggling to meet collection targets do not usually think of waste reduction and recycling. Composting is seen as one potential waste reduction strategy through the recycling of waste. As a result, a number of community-based composting projects have been piloted in the cities. Some projects have been successful in producing lasting impacts on the improvement of solid waste management. However, many projects could not support themselves or expand further when the external agencies discontinued their support. This thesis is an attempt to study the state of sustainability and replication potential of four community-based composting operations in Bangladesh.

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ZOUGBA, ISSIAKA. « Creazione e Condivisione di Valore in Ghana - un Approccio Strategico per il Business Sostenibile in un Paese in Via di Sviluppo ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2017. http://hdl.handle.net/10280/35570.

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Approcci strategici come lo shared value e il social impact vengono considerati strategie organizzative innovative in grado di ridurre il divario fra business e società facendo leva sulla sostenibilità. Seppur motivati da postulati promettenti, essi vengono spesso biasimati perché considerati scarsamente rilevanti o efficienti. La tesi analizza come alcune organizzazioni che hanno sottoscritto l’idea della creazione di valore condiviso siano in grado o meno di produrre benefici per loro stessi e per le comunità circostanti. Lo studio usa la metodologia del case study per indagare due multinazionali e quattro PMI in Ghana. La ricerca adotta un approccio multidisciplinare allo studio organizzativo e strategico per esaminare le insidie dell’azione strategica in Ghana. Essa analizza il modo in cui i principi socioeconomici locali condizionano le scelte strategiche e la performance organizzativa. Il contributo maggiore della tesi è l’introduzione di una versione rivisitata del sistema di azione concreto (Crozier e Friedberg), per identificare le strategie di creazione di valore condiviso e impatto sociale efficientemente radicate nel contesto. Inoltre, la ricerca dimostra che i principi socioeconomici locali sono dei meccanismi dinamici di resilienza messi in atto per mezzo di controllo, collusione, negoziazione e resistenza.
Strategic frameworks like shared value or social impact creation have been posited as innovative organizational strategies capable of mending the gap between business and society through inclusive sustainability. If their claims are promising, they still face much criticism concerning their relevance and effectiveness. The dissertation investigates how organizations which have endorsed the idea of shared value creation are efficient, or not, at yielding benefits for themselves and their host communities. It uses the case study methodology to explore four SMEs and two multinational companies in Ghana. The research builds on a multidisciplinary approach to organizational behavior and strategy to dig to ground the pitfalls of strategic action in Ghana, an epitome of the recent Africa Rising narrative. It scrutinizes the way local socioeconomic mores affect strategic choices and organizational performance. The major contribution of the thesis is to introduce a revisited version of Crozier and Friedberg’s concrete system of action for efficiently embedded strategies of shared value and social impact creation. With this, the work reveals that local socioeconomic mores are dynamic resilience mechanisms of control, collusion, bargaining, and/or resistance, which strategists must take account of in designing sustainable strategies, especially in Sub-Saharan Africa.

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ZOUGBA, ISSIAKA. « Creazione e Condivisione di Valore in Ghana - un Approccio Strategico per il Business Sostenibile in un Paese in Via di Sviluppo ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2017. http://hdl.handle.net/10280/35570.

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Approcci strategici come lo shared value e il social impact vengono considerati strategie organizzative innovative in grado di ridurre il divario fra business e società facendo leva sulla sostenibilità. Seppur motivati da postulati promettenti, essi vengono spesso biasimati perché considerati scarsamente rilevanti o efficienti. La tesi analizza come alcune organizzazioni che hanno sottoscritto l’idea della creazione di valore condiviso siano in grado o meno di produrre benefici per loro stessi e per le comunità circostanti. Lo studio usa la metodologia del case study per indagare due multinazionali e quattro PMI in Ghana. La ricerca adotta un approccio multidisciplinare allo studio organizzativo e strategico per esaminare le insidie dell’azione strategica in Ghana. Essa analizza il modo in cui i principi socioeconomici locali condizionano le scelte strategiche e la performance organizzativa. Il contributo maggiore della tesi è l’introduzione di una versione rivisitata del sistema di azione concreto (Crozier e Friedberg), per identificare le strategie di creazione di valore condiviso e impatto sociale efficientemente radicate nel contesto. Inoltre, la ricerca dimostra che i principi socioeconomici locali sono dei meccanismi dinamici di resilienza messi in atto per mezzo di controllo, collusione, negoziazione e resistenza.
Strategic frameworks like shared value or social impact creation have been posited as innovative organizational strategies capable of mending the gap between business and society through inclusive sustainability. If their claims are promising, they still face much criticism concerning their relevance and effectiveness. The dissertation investigates how organizations which have endorsed the idea of shared value creation are efficient, or not, at yielding benefits for themselves and their host communities. It uses the case study methodology to explore four SMEs and two multinational companies in Ghana. The research builds on a multidisciplinary approach to organizational behavior and strategy to dig to ground the pitfalls of strategic action in Ghana, an epitome of the recent Africa Rising narrative. It scrutinizes the way local socioeconomic mores affect strategic choices and organizational performance. The major contribution of the thesis is to introduce a revisited version of Crozier and Friedberg’s concrete system of action for efficiently embedded strategies of shared value and social impact creation. With this, the work reveals that local socioeconomic mores are dynamic resilience mechanisms of control, collusion, bargaining, and/or resistance, which strategists must take account of in designing sustainable strategies, especially in Sub-Saharan Africa.

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ROSSI, STEFANO FABIO. « «SOLO CIÒ CHE FRUTTIFICA E' VERO» FENOMENO E STRUTTURA IN HEINRICH ROMBACH ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2017. http://hdl.handle.net/10280/35770.

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La tesi prende in considerazione l'opera di H.Rombach (1923-2004) come esempio di sviluppo di alcune tesi heideggeriane e recupero di una certa tradizione filosofica tedesca che proprio la grande fama di Heidegger ha contribuito a rendere non operativa.
The thesis takes into consideration the work of H. Rombach (1923-2004) as a development of some Heideggerian intuitions, along with the recovery of some aspects of the German philosophical tradition that the great fame of Heidegger has contributed to obscure

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ROSSI, STEFANO FABIO. « «SOLO CIÒ CHE FRUTTIFICA E' VERO» FENOMENO E STRUTTURA IN HEINRICH ROMBACH ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2017. http://hdl.handle.net/10280/35770.

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La tesi prende in considerazione l'opera di H.Rombach (1923-2004) come esempio di sviluppo di alcune tesi heideggeriane e recupero di una certa tradizione filosofica tedesca che proprio la grande fama di Heidegger ha contribuito a rendere non operativa.
The thesis takes into consideration the work of H. Rombach (1923-2004) as a development of some Heideggerian intuitions, along with the recovery of some aspects of the German philosophical tradition that the great fame of Heidegger has contributed to obscure

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Alba, Fernández Raúl. « Caracterización del sistema attB/attP-(FI)C31 para la producción de adenovirus gutless ». Doctoral thesis, Universitat Autònoma de Barcelona, 2007. http://hdl.handle.net/10803/3570.

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El Ad es el vector más utilizado en ensayos clínicos con humanos. Para evitar la respuesta inmune celular inducida por los Ad de 1ª y 2ª generación, se han generado los vectores de 3ª generación, también llamados gutless o helper dependientes. Para producir estos vectores se necesitan tres elementos fundamentales: un Ad gutless con un gen terapéutico o marcador de interés; un Ad helper que aporte las proteínas virales necesarias in trans y; una línea celular permisiva para la producción de Ad. Los Ad gutless, al no contener ninguna región viral codificante, no generan respuesta inmune celular y tienen una capacidad de hasta 36 Kpb. Se ha demostrado que la expresión de los genes que incorporan puede durar toda la vida del organismo. Sin embargo, si bien presentan grandes ventajas, su uso en ensayos clínicos con humanos todavía no ha sido viable debido a dos grandes inconvenientes: la contaminación por Ad helper y su producción a gran escala. Para solventar el problema de la contaminación por Ad helper, en este trabajo se propone un nuevo sistema de generación de Ad gutless basado en la recombinasa ?C31-attB/attP. Los Ad helper generados llevan flanqueada su señal ? por las secuencias attB/attP. ?C31 es una recombinasa unidireccional con lo que una vez realizada su función, al escindir la señal de empaquetamiento, evita la reacción inversa. Esta característica supone una ventaja frente a otras recombinasas como Cre ó FLPe. Sorprendentemente, al incorporar la secuencia attB entre el extremo ITR del Ad y su señal de empaquetamiento, los Ad helper generados alargan su ciclo viral hasta las 56-60 horas, sin embargo, ello no afecta la replicación eficiente del genoma viral y la producción de proteínas virales. Asimismo, se ha demostrado que tanto el proceso de empaquetamiento como el de la maduración de la partícula viral están afectados. Se ha observado que la clonación de una segunda señal de empaquetamiento en el extremo 3' normaliza los niveles de producción de los Ad controles, confirmando así que el genoma no queda retenido en ninguna región nuclear. Ensayos de EMSA han mostrado que diferentes proteínas celulares se unen a la secuencia attB y probablemente la unión de una de ellas impida el correcto empaquetamiento del genoma adenoviral. Por todo ello, el empaquetamiento diferencial por tiempo de los Ad helper-attB/attP generados ha sido aprovechado para la producción de Ad gutless acotando su producción a las 36 horas (tiempo en el que un Ad control completa su ciclo viral). Sin embargo, en las producciones de Ad gutless, los niveles de contaminación por Ad helper fueron elevados y éstos aumentaban significativamente en los sucesivos pasos de amplificación. El análisis del extremo 5' del Ad helper confirmó que éste recombinaba con el Ad gutless por la señal de empaquetamiento perdiendo las secuencias de recombinación y así su capacidad de empaquetarse más lentamente. Sin embargo, la inversión de la señal de empaquetamiento supuso la demostración de que este efecto es fácilmente evitable lo que convierte al Ad helper Ad5/FC31.Cre.?R en una buena herramienta para la producción de Ad gutless.
Adenovirus is the most used vector in human clinical trials. In order to overcome cellular inmune response evoked by first and second generation adenovirus, third generation, also called gutless or helper-dependent adenovirus have been generated. Gutless adenovirus production needs three basic elements: a gutless adenovirus with a therapeutic or marker gene; a helper adenovirus which provide all viral proteins in trans and; a permisive cell line to produce adenovirus. Gutless adenovirus, without any codificant viral region, don't evoke cellular inmune response and can incorporate DNA inserts up to 36 Kb. It has been reported that the expresion of incorporated genes can last the whole life of the organism. Nevertheless, its use in human clinial trials is not suitable due two important inconvenients: helper adenovirus contamination and up-scale processes. To solve helper adenovirus contamination problem, this present work propose a new adenovirus gutless generation system based on ?C31-attB/attP recombinase. Helper adenovirus generated have flanked its packaging signal (?) by attB/attP sequences. ?C31 is an unidirectional recombinase which avoid reverse reaction. This characteristic is an important advantage in front of other recombinases such as Cre or FLPe. Surprisingly, attB sequence incorporated between Ad-ITR and ? lengthens adenovirus cycle up to 56-60 hours, However, this effect don't affect efficient genome replication or protein shyntesis. Moreover, it has been shown that packaging and maturation processes are affected. It has been observed that the cloning of a second ? in the 3'-ITR normalize production levels in comparison to control adenvovirus, proving adenovirus genome is not trapped in any nuclear region. EMSA assays have shown different cellular proteins interact with attB sequence and likely the interaction of one of this cellular proteins impairs the correct packaging of adenovirus genome. For this reason, differential packaging in time of attB/attP-helper adenovirus generated have been used to produce gutless adenovirus limiting production times at 36 hours (time when control adenovirus finish its viral cycle) . However, in gutless adenovirus productions, helper adenovirus contamination levels were high and they increase significantly in the successive amplification steps. The 5' extreme analysis showed helper and gutless adenovirus recombine by their ? loosing recombination sequences and, in this way, helper adenovirus slow packaging capacity. Nevertheless, the inversion of ? showed this effect can be easily avoided which make Ad5/FC31.Cre.?R helper adenovirus a good tool for gutless adenovirus production.

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Dash, Manas Ranjan. « Thermo-mechanical durability assessment and microstructural characterization of 95.5Pb2Sn2.5Ag high temperature solder ». College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3570.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2006.
Thesis research directed by: Dept. of Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Barbeitos, Marcos Soares. « Variação de formas de crescimento de Montastraea cavernosa (Linnaeus, 1767) (Cnidaria, Anthozoa, Scleractinia) : uma abordagem modular ». Universidade Federal do Rio de Janeiro, 2000. http://hdl.handle.net/11422/3570.

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Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2018-01-31T00:18:00Z No. of bitstreams: 1 414933.pdf: 15896634 bytes, checksum: 6e86128ee7096bec949c9b616f290355 (MD5)
Made available in DSpace on 2018-01-31T00:18:00Z (GMT). No. of bitstreams: 1 414933.pdf: 15896634 bytes, checksum: 6e86128ee7096bec949c9b616f290355 (MD5) Previous issue date: 2000
CAPES
Animais clonais crescem por acréscimo de unidades funcionais (zoóides) as quais formam a colônia. A abordagem modular consiste em descrever a forma das colônias do ponto de vista do arranjo e tamanho dos módulos. A abordagem modular foi usada aqui para quantificar variações na forma de crescimento do coral Montastraea cavernosa a partir da mensuração do arranjo e áreas dos pólipos na face interna do tecido colonial. Foram coletadas 46 amostras no Parcel das Paredes (BA) e João Pessoa (PB). Os resultados mostraram que área dos pólipos é parcialmente explicada por fatores ligados ao espaçamento entre eles. Estes fatores variam com a forma da colônia e com a faixa de tamanho de pólipos considerada. Foi proposto um modelo conceitual hipotético para a relação entre a forma de crescimento colonial, o tamanho e a organização dos pólipos. São discutidas possíveis razões evolutivas para o modelo proposto e implicações deste para estudos morfométricos da espécie.
Clonal animals grow through addition of functional units (zooids), whose assemblage constitutes a colony. The modular approach consists in describing colony form from the arrangement and size of modules. The modular approach was used here to access variations in growth forms of the coral Montastraea cavernosa using the arrangement and the size of polyps in the inner face of the colonial of 46 samples collected in Parcel das Paredes (BA) and João Pessoa (PB). Results showed that area of the polyps is partially explained by factors related to the spacing among them. These factors vary with the form of the colony and with the range of polyp sizes being analyzed. A hypothetical conceptual model for the relationship among colonial growth forms, polyp sizes and organization is proposed. Possible evolutionary reasons for such a model are discussed as well as possible implications to morphometric studies of this species.

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Skornicka, Erin L. « The effect of blood collection methods on the expression of monocyte cellular adhesion molecules / ». Connect to online version, 1996. http://hdl.handle.net/1989/3570.

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