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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
651

Design synthesis of multistable equilibrium systems

King, Carey Wayne 28 August 2008 (has links)
Not available / text
652

Appealing to intuitions

Langkau, Julia January 2013 (has links)
This thesis is concerned with the ontology, epistemology, and methodology of intuitions in philosophy. It consists of an introduction, Chapter 1, and three main parts. In the first part, Chapter 2, I defend an account of intuitions as appearance states according to which intuitions cannot be reduced to beliefs or belief-like states. I argue that an account of intuitions as appearance states can explain some crucial phenomena with respect to intuitions better than popular accounts in the current debate over the ontology of intuitions. The second part, Chapters 3 to 5, is a reply to Timothy Williamson's (2004, 2007) view on the epistemology and methodology of intuitions. The practice of appealing to the fact that we have an intuition as evidence from thought experiments has recently been criticised by experimental philosophers. Williamson argues that since thought experiments reliably lead to knowledge of the content of our intuition, we can avoid this criticism and the resulting sceptical threat by appealing to the content of the intuition. I agree that thought experiments usually lead to knowledge of the content of our intuition. However, I show that appealing to the fact that we have an intuition is a common and useful practice. I defend the view that for methodological reasons, we ought to appeal to the fact that we have an intuition as initial evidence from thought experiments. The third part, Chapter 6, is devoted to a paradigm method involving intuitions: the method of reflective equilibrium. Some philosophers have recently claimed that it is trivial and could even accommodate scepticism about the reliability of intuitions. I argue that reflective equilibrium is not compatible with such scepticism. While it is compatible with the view I defend in the second part of the thesis, more specific methodological claims have to be made.
653

Effect of micro-gravity on the microstructural evolution during liquid phase sintering

Tewari, Asim 05 1900 (has links)
No description available.
654

The relationship between balance and functional outcomes of subacute in-patient rehabilitation in stroke patients

Tsang, Yuen., 曾苑. January 2004 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
655

IDENTIFICATION OF INTERMEDIATE PHASES FORMED BY DIFFUSION IN THE BORON - NICKEL SYSTEM

Giancola, John Robert January 1968 (has links)
No description available.
656

Competitive supply chain and revenue management : four essays

Zhao, Xuan 05 1900 (has links)
This dissertation includes four independent essays. Essay one (chapter two) considers a two-echelon, two-supply chain (SC) system in which manufacturers supply a generic product to their exclusive retailers, who then use service level and retail price to compete for heterogeneous consumers. We question: how do varied consumer preferences get reflected not only in differentiated products/services, but through them to the choice of SC structure that delivers them? We find that SCs can strategically manipulate the product/service strategy and SC structure to hedge themselves from horizontal competition. The key finding is that in a market where consumers have stronger diminishing marginal utility on service, then less differentiated products/services will be observed, and only decentralized supply chains can be the market equilibrium. This is in contrast to the well-known result in marketing that choosing vertical integration is always a Nash equilibrium, and that choosing decentralization can only be a Nash equilibrium when product substitutability is high. Essay two (chapter three) explores the classical revenue management problem in a competitive context, with both price and seat inventory competition. The main question is how should management make strategic marketing (pricing) and operational (seat allocation) decisions in such a competitive market? Do the conventional approaches (models and algorithms based on a monopoly market) give us the appropriate strategies? We find that in a market where price competition dominates, managers should set a lower price and safety protection level for full fare customers than in a monopoly or alliance market. In a market where seat inventory competition dominates, managers should set a higher price and safety protection level than a monopoly or alliance would. Interestingly, in a market where the two levels of competition are more evenly matched, managers should set a lower price and a higher safety protection level than a monopoly. We also explore the effect of the degree of competition and the market structure on the strategic decisions, and whether there is a first adopter advantage or second adopter disadvantage with revenue management. Essay three aims to extend the understanding of the Newsvendor model to a competitive framework. In a market with both price and inventory competition, newsvendors can gain customers with price and secure the sales with availability. We find that the newsvendors should adjust their inventory (safety stock or total inventory) and pricing strategies responsively to the nature of the competitive market. The profits of the newsvendors and their suppliers are also different under different competitive contexts. Both the Nash equilibrium strategy and the players' profits are influenced by the demand correlation and variability, but in different ways under different competitive scenarios. These observations provide some theoretical basis for the strategic selection made by newsvendors operating in certain competitive markets. Essay four (chapter five) explores the issue of competitors cooperating. It is a commonplace observation that even the most competitive firms often find it in their best interests to cooperate. An example of cooperation in operations management is when two supply chains agree in advance to transship or 'pool' surplus product for use by another. The alternative is to let their customers switch unsatisfied demand to a competitor. Which is preferable, and how does such a preference depend on the many parameters, prices, the nature of competition, the degree of competition, wholesale prices etc? To get answers, we study a stylized model under three market environments: a market with an exogenous retail price, an endogenous retail price, and with price competition. The summary answer is that strong price competition between substitutable goods should lead to caution in signing transshipment contracts. But with little price competition and particularly where retailers are free to set the transshipment price, then transshipment is probably the way to go. We also address the issue of an optimal transshipment price in each scenario, and compare the Nash equilibrium strategies between competing and transshipping.
657

Investigations into the Shear Strength Reduction method using distinct element models

Fournier, Mathew 11 1900 (has links)
This thesis reports a detailed investigation into the use of the Shear Strength Reduction (SSR) method to determine factor of safety values in discontinuum models using the Universal Distinct Element Code. The SSR method depends on the definition of failure within the model and two different criteria were compared: the numerical unbalanced force definition and a more qualitative displacement-monitoring based method. A parametric study was first undertaken, using a simple homogeneous rock slope, with three different joint networks representing common kinematic states. Lessons learned from this study were then applied to a more complex case history used for validation of the SSR method. The discontinuum models allow for the failure surface to propagate based on constitutive models that better idealize the rockmass than simpler methods such as limit equilibrium (e.g. either method of slices or wedge solutions) and even numerical continuum models (e.g. finite difference, finite element). Joints are explicitly modelled and can exert a range of influences on the SSR result. Simple elasto-plastic models are used for both the intact rock and joint properties. Strain-softening models are also discussed with respect to the SSR method. The results presented highlight several important relationships to consider related to both numerical procedures and numerical input parameters. The case history was modelled similar to how a typical forward analysis would be undertaken: i.e. simple models with complexities added incrementally. The results for this case generally depict a rotational failure mode with a reduced factor of safety due to the presence of joints within the rockmass when compared to a traditional limit equilibrium analysis. Some models with large persistence of steeply dipping joints were able to capture the actual failure surface. Softening models were employed in order to mimic the generation and propagation of joints through the rockmass in a continuum; however, only discontinuum models using explicitly defined joints in the model were able to capture the correct failure surface.
658

The econometric critique of applied General Equilibrium modeling: a comparative assessment with application to carbon taxes in Canada

McKitrick, Ross Ronald 11 1900 (has links)
Computable General Equilibrium (CGE) models are among the most influential tools in applied economics. In the past few years, however, some serious questions have been raised about the validity of these models. The core of the critique is that the parameter selection criteria and the functional forms used are at odds with contemporary standards of practice in econometrics. After surveying the relevant literature, which I refer to as the 'econometric critique', a formal summary of the case against standard CGE modeling is presented, as is an alternative econometric-based modeling strategy which answers the critique. I then work through a comparative CGE modeling experiment designed to assess the contrasting methods. It is found that the parameter selection rule influences model predictions in individual sectors, but industry- and economy-wide aggregates do not appear to be much affected by reparameterizing a CGE model according to econometric criteria. By contrast, the choice of functional forms affects not only industry-specific results, but aggregate results as well, even for small policy shocks. However flexible functional forms are difficult to implement in CGE models because global monotonicity must be maintained. In the second and third chapters, I adapt one of the models to analyze the effects of carbon taxes in Canada. I review an approach called 'double dividend' taxation, in which the revenues from carbon taxes are used to reduce the rates of other distortionary taxes, so an overall efficiency gain can potentially be realized whether or not the reduction in pollution improves welfare. This eliminates the need to measure benefits, and in an international context, would obviate the free-rider problem. I demonstrate the existence of a double dividend strategy for carbon taxation in Canada in the short run. In chapter three, however, a long run extension of the model shows that the double dividend does not persist over time. Nevertheless, choosing an efficient revenue-recycling option can significantly reduce the implementation cost of the carbon tax.
659

Equilibri de tronc predictor de la funció motora en l'emiplègic vascular

Duarte Oller, Esther 16 June 2006 (has links)
TRUNK BALANCE AS A PREDICTOR OF MOTOR OUTCOME IN PATIENTS WITH STROKE ABSTRACTBackground: The search for predictors of functional stroke outcome has always been matter of research in Physical Medicine and Rehabilitation. Outcome prediction at an early stage enables clinicians not only to inform patients and their families, but also to set realistic therapeutic goals. A lot of prognostic studies have evaluated several factors, which either individually or in combination claim to predict functional outcome in stroke. The Trunk Control Test (TCT) proposed by Collin & Wade administered at 6 weeks post-stroke is a predictor of the walking ability at 18 weeks. The TCT reliability and validity has been demonstrated in stroke patients, as well as its positive correlation with disability at hospital discharge from in-patient rehabilitation measured with the Functional Independence Measure (FIM). In a previous study, a predictive model which only includes the FIM and the TCT measured at admission of patients to a rehabilitation ward, predicts 66.5% of the variability of the functional level at discharge (total FIM). Objective: To develop an early model to predict motor function (disability, walking ability and balance)at 6 months, taking into account the TCT and other valid predictors evaluated in the first and second week after suffering a stroke.Patients and Methods: Seventy-five consecutive patients with first stroke who were admitted to a rehabilitation hospital were studied. Sex, age, the stroke type, urinary incontinence, the National Institutes of Health Stroke Scales (NIHSS) and the TCT scores (assessed at first and second week post-stroke) as independent variables. Motor function outcome at 6 months after stroke is defined by the use the Rankin score, the motor FIM and the Berg Balance Scale (BBS).Results: Older patients, women and those with initial urinary incontinence and lower TCT and NIHSS scores showed significantly worse motor outcomes at first and six months after the stroke (Rankin, motor FIM and BBS). A multiple regression reveals that only age and the TCT (at 14 days after stroke) accounts for the 61.1% of the variance in the motor FIM score at 6 months after stroke. When the TCT is registered at 7 days after stroke, age and the TCT accounts for the 51.7% of the motor FIM variance. A cluster analysis identifies 12 patients with low outcome scores: Rankin 4-5, motor FIM < 59 and BBS < 5. The ROC curves show a better prediction ability for the TCT than the NIHSS at 14 days after stroke. Logistic regression is used to predict the probability of achieving in this group with low motor scores. The TCT &#61603; 50 at 14 days after stroke is a significant predictive factor of poor motor outcome at 6 months after stroke (Sensibility 83.3%, Specificity 85.7%) (OR=30.0, 95% CI 4.7 - 247.3). The TCT &#61603; 24 at 7 days after stroke is a significant, but obviously worse predictive factor of poor motor outcome (Sensibility 66.7%, Specificity 89.3%) (OR=16.7, 95% CI 3.2 - 97.5). Discussion and conclusions: Age, sex, urinary incontinence, TCT and NIHSS scores are related with disability, balance and walking ability six months after the stroke. It is possible to approach to the motor functional outcome at 6 months after stroke by the early use of data easily recorded as age and the TCT. In this study the TCT even overcomes the NIHSS, a comprehensive neurological measure whose ability to predicts outcome has been well documented in stroke patients. The reproducibility of this model must be cross-validated in future studies. The TCT registered at 14 days provides better prediction values compared with those obtained at 7 days after stroke. This study shows that the TCT early administered predicts motor outcome at six months after stroke.EQUILIBRI DE TRONC: PREDICTOR DE LA FUNCIÓ MOTORA EN L'HEMIPLÈGIC VASCULAR RESUMIntroducció: La cerca de factors predictors del resultat funcional després de patir un ictus és objecte constant d'investigació en Medicina Física i Rehabilitació. Un pronòstic funcional en fases inicials permet al clínic informar als pacients i a la seva familia, però també establir objectius terapèutics realistes. Molts estudis han avaluat la capacitat predictora de diferents factors individual i combinadament. El Test de Control de Tronc (TCT) registrat a les 6 setmanes de l'ictus és un predictor de la capacitat de marxa a les 18 setmanes. La fiabilitat i validesa del TCT s'ha demostrat en pacients amb ictus, així com la seva correlació positiva amb la discapacitat a l'alta hospitalaria. Un model predictiu que inclou només el TCT i el Functional Independence Measure (FIM) registrats a l'ingrés en la unitat de rehabilitació d'hospitalització aguda prediu el 66.5% de la variabilitat del FIM a l'alta.Objectius: Conèixer la relació de les variables predictores amb els resultats de funció motora global al mes i als sis mesos de l'ictus. Construir un model de predicció precoç de la funció motora (discapacitat, capacitat de marxa i equilibri) als 6 mesos, tenint en compte el TCT i altres predictors vàlids avaluats en la primera i en la segona setmana després de patir l'ictus.Pacients i Mètode: estudi longitudinal i prospectiu en 75 pacients consecutius ingressats per un primer episodi d'ictus. Les variables independents van ser: edat, sexe, tipus d'ictus, incontinencia urinària, l'escala d'ictus National Institutes of Health Stroke Scales (NIHSS) i el TCT (recollits en la primera i segona setmanes de l'ictus). Els resultats de funció motora al mes i als 6 mesos de l'ictus es van definir amb l'escala de Rankin, la subescala motora del FIM i l'escala d'equilibri Berg Balance Scale (BBS).Resultats: els pacients de més edat, les dones i els que tenen incontinència urinària inicial i puntuacions més baixes de TCT i NIHSS són els que presenten significativament pitjors resultats de funció motora tant en el primer com en el sisè mes de l'ictus (Rankin, FIM motor i BBS). Una anàlisi de regressió múltipla determina que només amb l'edat i el TCT de la segona setmana s'explica el 61.1% de la variabilitat del FIM motor als 6 mesos de l'ictus. Quan el TCT es registra en el setè dia de l'ictus, l'edat i el TCT expliquen el 51.7% de la variabilitat del FIM motor. Una anàlisi de conglomerats identifica 12 pacients amb resultats baixos de funció motora: Rankin 4-5, FIM motor < 59 i BBS < 5. Les corbes ROC mostren que la millor capacitat predictora correspon al TCT de la segona setmana, per sobre del NIHSS. La probabilitat de tenir un mal resultat motor, es a dir, d'estar entre aquests 12 pacients es calcula mitjançant una anàlisi de regressió logística. Un TCT &#61603; 50 en la segona setmana de l'ictus és un factor predictiu de mal resultat motor als 6 mesos (Sensibilitat 83.3%, Especificitat 85.7%) (OR=30.0, IC 95% 4.7 - 247.3). Un TCT &#61603; 24 en la primera setmana també és un factor predictor significatiu, tot i que menys potent, de obtenir un mal resultat motor als 6 mesos (Sensibilitat 66.7%, Especificitat 89.3%) (OR=16.7, IC 95% 3.2 - 97.5).Conclusions: L'edat, el sexe, la incontinència urinària, el TCT i el NIHSS inicials són factors relacionats amb la discapacitat, equilibri i capacitat de marxa 6 mesos després de l'ictus. És possible aproximar-nos al resultat funcional motor als 6 mesos després de patir l'ictus amb la utilització precoç de dades de fácil recollida com l'edat i el TCT. El TCT recollit en fases inicials prediu el resultat motor als 6 mesos de l'ictus.
660

Studies on phase behaviour and surface properties of polymer systems.

Siow, Kok-Siong. January 1972 (has links)
No description available.

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