Aplicação da metodologia numérica “fast bounds crack” para uma estimativa eficiente da evolução do tamanho de trinca

A significant part of the life of a mechanical component occurs, the crack propagation stage in fatigue. Currently, it is had several mathematical models to describe the crack growth behavior. These models are classified into two categories in terms of stress range amplitude: constant and variable. In general, these propagation models are formulated as an initial value problem, and from this, the evolution curve of the crack is obtained by applying a numerical method. This dissertation presented the application of the methodology "Fast Bounds Crack" for the establishment of upper and lower bounds functions for model evolution of crack size. The performance of this methodology was evaluated by the relative deviation and computational times, in relation to approximate numerical solutions obtained by the Runge-Kutta method of 4th explicit order (RK4). Has been reached a maximum relative deviation of 5.92% and the computational time was, for examples solved, 130,000 times more higher than achieved by the method RK4. Was performed yet an Engineering application in order to obtain an approximate numerical solution, from the arithmetic mean of the upper and lower bounds obtained in the methodology applied in this work, when you don’t know the law of evolution. The maximum relative error found in this application was 2.08% which proves the efficiency of the methodology "Fast Bounds Crack".

A rehabilitation intervention to promote physical recovery following intensive care: a detailed description of construct development, rationale and content together with proposed taxonomy to capture processes in a randomised controlled trial.

Background: increasing numbers of patients are surviving critical illness, but survival may be associated with a constellation of physical and psychological sequelae that can cause on going disability and reduced health-related quality of life. Limited evidence currently exists to guide the optimum structure, timing, and content of rehabilitation programmes. There is a need to both develop and evaluate interventions to support and expedite recovery during the post-ICU discharge period. This paper describes the construct development for a complex rehabilitation intervention intended to promote physical recovery following critical illness. The intervention is currently being evaluated in a randomised trial (ISRCTN09412438; funder Chief Scientists Office, Scotland). Methods: the intervention was developed using the Medical Research Council (MRC) framework for developing complex healthcare interventions. We ensured representation from a wide variety of stakeholders including content experts from multiple specialties, methodologists, and patient representation. The intervention construct was initially based on literature review, local observational and audit work, qualitative studies with ICU survivors, and brainstorming activities. Iterative refinement was aided by the publication of a National Institute for Health and Care Excellence guideline (No. 83), publicly available patient stories (Healthtalkonline), a stakeholder event in collaboration with the James Lind Alliance, and local piloting. Modelling and further work involved a feasibility trial and development of a novel generic rehabilitation assistant (GRA) role. Several rounds of external peer review during successive funding applications also contributed to development. Results: the final construct for the complex intervention involved a dedicated GRA trained to pre-defined competencies across multiple rehabilitation domains (physiotherapy, dietetics, occupational therapy, and speech/language therapy), with specific training in post-critical illness issues. The intervention was from ICU discharge to 3 months post-discharge, including inpatient and post-hospital discharge elements. Clear strategies to provide information to patients/families were included. A detailed taxonomy was developed to define and describe the processes undertaken, and capture them during the trial. The detailed process measure description, together with a range of patient, health service, and economic outcomes were successfully mapped on to the modified CONSORT recommendations for reporting non-pharmacologic trial interventions. Conclusions: the MRC complex intervention framework was an effective guide to developing a novel post-ICU rehabilitation intervention. Combining a clearly defined new healthcare role with a detailed taxonomy of process and activity enabled the intervention to be clearly described for the purpose of trial delivery and reporting. These data will be useful when interpreting the results of the randomised trial, will increase internal and external trial validity, and help others implement the intervention if the intervention proves clinically and cost effective.

Low-Volatility Anomaly in Helsinki Stock Exchange

International research shows that low-volatility stocks have beaten high-volatility stocks in terms of returns for decades on multiple markets. This abbreviation from traditional risk-return framework is known as low-volatility anomaly. This study focuses on explaining the anomaly and finding how strongly it appears in NASDAQ OMX Helsinki stock exchange. Data consists of all listed companies starting from 2001 and ending close to 2015. Methodology follows closely Baker and Haugen (2012) by sorting companies into deciles according to 3-month volatility and then calculating monthly returns for these different volatility groups. Annualized return for the lowest volatility decile is 8.85 %, while highest volatility decile destroys wealth at rate of -19.96 % per annum. Results are parallel also in quintiles that represent larger amount of companies and thus dilute outliers. Observation period captures financial crisis of 2007-2008 and European debt crisis, which embodies as low main index annual return of 1 %, but at the same time proves the success of low-volatility strategy. Low-volatility anomaly is driven by multiple reasons such as leverage constrained trading and managerial incentives which both prompt to invest in risky assets, but behavioral matters also have major weight in maintaining the anomaly.

Efeito dos dias da semana na volatilidade do índice S&P 500: Um estudo empírico

Mestrado em Contabilidade e Análise Financeira,

ESSAYS ON THE WTO ACCESSION, HOUSEHOLD INCOME AND MULTIDIMENSIONAL POVERTY: EVIDENCE FROM CHINA

In the course of integrating into the global market, especially since China’s WTO accession, China has achieved remarkable GDP growth and has become the second largest economy in the world. These economic achievements have substantially increased Chinese incomes and have generated more government revenue for social progress. However, China’s economic progress, in itself, is neither sufficient for achieving desirable development outcomes nor a guarantee for expanding peoples’ capabilities. In fact, a narrow emphasis on GDP growth proves to be unsustainable, and may eventually harm the life quality of Chinese citizens. Without the right set of policies, a deepening trade-openness policy in China may enlarge social disparities and some people may further be deprived of basic public services and opportunities. To address these concerns, this dissertation, a set of three essays in Chapters 2-4, examines the impact of China's WTO accession on income distribution, compares China’s income and multidimensional poverty reduction and investigates the factors, including the WTO accession, that predict multidimensional poverty. By exploiting the exogenous variation in exposure to tariff changes across provinces and over time, Chapter 2 (Essay 1) estimates the causal effects of trade shocks and finds that China’s WTO accession has led to an increase in average household income, but its impacts are not evenly distributed. Households in urban areas have benefited more significantly than those in rural areas. Households with members working in the private sector have benefited more significantly than those in the public sector. However, the WTO accession has contributed to reducing income inequality between higher and lower income groups. Chapter 3 (Essay 2) explains and applies the Alkire and Foster Method (AF Method), examines multidimensional poverty in China and compares it with income poverty. It finds that China’s multidimensional poverty has declined dramatically during the period from 1989-2011. Reduction rates and patterns, however, vary by dimensions: multidimensional poverty reduction exhibits unbalanced regional progress as well as varies by province and between rural and urban areas. In comparison with income poverty, multidimensional poverty reduction does not always coincide with economic growth. Moreover, if one applies a single measure ─ either that of income or multidimensional poverty ─ a certain proportion of those who are poor remain unrecognized. By applying a logistic regression model, Chapter 4 (Essay 3) examines factors that predict multidimensional poverty and finds that the major factors predicting multidimensional poverty in China include household size, education level of the household head, health insurance coverage, geographic location, and the openness of the local economy. In order to alleviate multidimensional poverty, efforts should be targeted to (i) expand education opportunities for the household heads with low levels of education, (ii) develop appropriate geographic policies to narrow regional gaps and (iii) make macroeconomic policies work for the poor.

Minimalist Hardware Architectures for Agent Tracking and Guidance

The philosophy of minimalism in robotics promotes gaining an understanding of sensing and computational requirements for solving a task. This minimalist approach lies in contrast to the common practice of first taking an existing sensory motor system, and only afterwards determining how to apply the robotic system to the task. While it may seem convenient to simply apply existing hardware systems to the task at hand, this design philosophy often proves to be wasteful in terms of energy consumption and cost, along with unnecessary complexity and decreased reliability. While impressive in terms of their versatility, complex robots such as the PR2 (which cost hundreds of thousands of dollars) are impractical for many common applications. Instead, if a specific task is required, sensing and computational requirements can be determined specific to that task, and a clever hardware implementation can be built to accomplish the task. Since this minimalist hardware would be designed around accomplishing the specified task, significant reductions in hardware complexity can be obtained. This can lead to huge advantages in battery life, cost, and reliability. Even if cost is of no concern, battery life is often a limiting factor in many applications. Thus, a minimalist hardware system is critical in achieving the system requirements. In this thesis, we will discuss an implementation of a counting, tracking, and actuation system as it relates to ergodic bodies to illustrate a minimalist design methodology.

Volitionstheorie der Gesundheitserziehung

Es werden neue theoretische Überlegungen vorgetragen, die dazu beitragen können, die gesundheitspädagogische Forschung zu stimulieren und die Praxis der Gesundheitserziehung zu beeinflussen. Dabei werden Phasen des Selbstregulationsprozesses, der zu einem Risikoverhalten oder Gesundheitsverhalten führt, unterschieden. Die anfängliche Motivationsphase ist durch das Abwägen zwischen Alternativen gekennzeichnet und schließt mit einer Zielintention ab. In der nachfolgenden Volitionsphase geht es um die Umsetzung einer Absicht in einem Handlungsversuch sowie um die Aufrechterhaltung des Gesundheitsverhaltens gegen Widerstände. Auch hier erweist sich die Kompetenzerwartung als eine wichtige Einflußgröße. Abschließend werden Konsequenzen für die Gesundheitserziehung diskutiert. (DIPF/Orig.)

Quantitative Derivation of Effective Evolution Equations for the Dynamics of Bose-Einstein Condensates

This thesis proves certain results concerning an important question in non-equilibrium quantum statistical mechanics which is the derivation of effective evolution equations approximating the dynamics of a system of large number of bosons initially at equilibrium (ground state at very low temperatures). The dynamics of such systems are governed by the time-dependent linear many-body Schroedinger equation from which it is typically difficult to extract useful information due to the number of particles being large. We will study quantitatively (i.e. with explicit bounds on the error) how a suitable one particle non-linear Schroedinger equation arises in the mean field limit as number of particles N → ∞ and how the appropriate corrections to the mean field will provide better approximations of the exact dynamics. In the first part of this thesis we consider the evolution of N bosons, where N is large, with two-body interactions of the form N³ᵝv(Nᵝ⋅), 0≤β≤1. The parameter β measures the strength and the range of interactions. We compare the exact evolution with an approximation which considers the evolution of a mean field coupled with an appropriate description of pair excitations, see [18,19] by Grillakis-Machedon-Margetis. We extend the results for 0 ≤ β < 1/3 in [19, 20] to the case of β < 1/2 and obtain an error bound of the form p(t)/Nᵅ, where α>0 and p(t) is a polynomial, which implies a specific rate of convergence as N → ∞. In the second part, utilizing estimates of the type discussed in the first part, we compare the exact evolution with the mean field approximation in the sense of marginals. We prove that the exact evolution is close to the approximate in trace norm for times of the order o(1)√N compared to log(o(1)N) as obtained in Chen-Lee-Schlein [6] for the Hartree evolution. Estimates of similar type are obtained for stronger interactions as well.

Desenvolvimento de equipamento para medir os intervalos R-R

This study aimed to develop a device to measure RR intervals, which have high correlation with the values of the gold standard device of electrocardiograph (ECG), by the time domain and frequency domain indices. To this end, a study was conducted with 18 students of Jiu-Jitsu, males with 35.5 ± 8.6 years, at least a weekly frequency of 3 times and one year training. The location was at the academy Gracie Barra de Curitiba PR. They underwent an examination at rest for a period of 7 minutes and then the results were converted into heart rate variability (HRV) and analyzed by the indexes in the time domain and the frequency domain. The results were compared statistically using the Pearson test and intraclass correlation (ICC) and according to them proves to be viable the development of this equipment, which is highly correlated and excellent reproducibility for measuring the RR intervals.

Produção de biodiesel de blendas dos óleos de mamona e arroz em escala piloto

A utilização do óleo de mamona como matéria-prima para produção de biodiesel mostra-se inviável na combustão interna do motor devido sua natureza química incomum que lhe confere especificações acima do permitido nas especificações técnicas da legislação nacional brasileira. Desta forma, a blenda com óleo de arroz refinado (OM:OA) qualifica o biodiesel atendendo a legislação nacional, além de corrigir a elevada acidez do óleo bruto de mamona prejudicial ao processo de transesterificação homogênea básica. No presente estudo realizou-se a produção de biodiesel etílico em escala piloto a partir de blendas de óleo bruto de mamona e óleo refinado de arroz em dois processos: o primeiro processo adotando a mistura direta dos dois óleos e o segundo processo pela esterificação antecipada do óleo bruto de mamona. Ambos os processos foram aplicados visando tanto definir os critérios de processo (acidez inicial) quanto o cumprimento das especificações técnicas (viscosidade e densidade). A produção em escala piloto (200 litros/batelada) foi realizada na Usina Demonstrativa para Produção de Biodiesel – BIOSUL (Edital FINEP, 2005) da Universidade Federal do Rio Grande - FURG utilizando em ambos os processos transesterificação, com hidróxido de sódio, e esterificação com ácido sulfúrico. Os processos apresentaram resultados satisfatórios, sendo o processo de mistura direta (Processo A) o que obteve melhores rendimentos (94,04%, blenda 20:80) enquanto que o processo de pré- esterificação (Processo B) foi aquele que proporcionou a maior fração de óleo de mamona na blenda (80,36%, 33:67). Os resultados para o Processo A de glicerol livre, monoacilgliceróis, diacilgliceróis, triacilgliceróis e de glicerol total foram, respectivamente, de 1,322 %, 6,092 %, 1,000 %, 0,884 e 3,152%. Neste estudo foi comprovada a viabilidade do processamento, em batelada, de blendas dos óleos de mamona e arroz. O óleo de mamona bruto pode ser utilizado em até 30% produzindo biodiesel dentro da legislação, verificando-se assim a viabilidade do uso da mamona na produção de biocombustíveis.

La colecistectomía laparoscópica en el Hospital Vicente Corral Moscoso de Cuenca, 1994-2008

Antecedentes. La colecistectomía laparoscópica (CL, Cole-Lap) es el tratamiento de elección en la patología biliar benigna, la que presenta una elevada incidencia en nuestra ciudad y país. En el hospital Vicente Corral, cirujanos en formación y docentes, han participado en el desarrollo de esta técnica desde su inicio. Objetivo. Describir y compartir la experiencia de 14 años de colecistectomía laparoscópica en el Hospital Vicente Corral M. Métodos. Se presenta la casuística descriptiva y retrospectiva de 2.200 pacientes intervenidos por colecistectomía laparoscópica desde mayo de 1994 hasta enero 2008. Resultados. De 2.200 CL, el 79% son de sexo femenino, con promedio de edad de 43 años, con diagnóstico intraoperatorio de colecistitis crónica litiásica en el 82%. Se presentaron complicaciones entre mayores y menores en el 38%, las perforaciones de vesícula con salida de la bilis y las hemorragias provenientes de la arteria cística fueron las más frecuentes. La lesión de la vía biliar principal se registró en el 0.12%. En las 100 primeras cirugías se presentaron 25 complicaciones, mientras que en las 100 últimas fueron 34. El tiempo operatorio promedio fue de 35 minutos en el 2008. Discusión. La colecistectomía laparoscópica demuestra, en nuestro estudio, ser un procedimiento seguro y efectivo en pacientes con colecistitis calculosa aguda o crónica.

Współczesna debata telewizyjna a konflikt destruktywny

W artykule dowodzi się tezy, że współczesne debaty publiczne, emitowane w telewizji (takie jak emitowany od 2004 roku w TVP2 program Jana Pospieszalskiego „Warto rozmawiać”), są zdarzeniami komunikacyjnymi zasadzonymi na konflikcie destruktywnym, a więc takim, który wg L. Kriesberga, nastawiony jest nie na problem wywołujący frustrację, ale jest manifestacją agresji, a celem sporu staje się nie pokonanie różnic dzielących strony, ale pokonanie oponenta. Wynika to z sytuacji komunikacyjnej debaty telewizyjnej i nastawienia w pierwszej kolejności na zdobycie uwagi, a potem zaspokajanie potrzeb odbiorcy sekundarnego – widza. Podporządkowane są temu takie elementy, jak wybór tematu debaty, jej scenariusz, dobór uczestników, a w dalszej kolejności ich zachowania werbalne i niewerbalne. W rezultacie, w debacie telewizyjnej złamane zostają typowe dla debaty konstruktywnej reguły i strategie, i zastąpione zostają zachowaniami typowymi dla konfliktu destruktywnego, takimi jak: brak otwartości na argumenty drugiej strony, nastawienie na pokonanie antagonisty, niechęć do szukania innych rozwiązań, jak tylko moja wygrana - twoja przegrana, działania nastawione na prowokację i podważanie wiarygodności partnera, przenoszenie ciężaru debaty ze sprawy na osobę, posługiwanie się argumentacją niemerytoryczną, niezgoda na konstruowanie wspólnego stanowiska. Taki wzorzec debaty telewizyjnej, która stała się pośpieszną, bezproduktywną prezentacją rozbieżnych stanowisk, nie prowadzącą do żadnych konkluzji, nastawioną najwyżej na obrażenie rozmówcy i dostarczenie widzowi krótkotrwałych emocji, buduje powszechne przekonania o niemożności dialogu i porozumienia w dyskursie publicznym i dominującym w nim antagonizmie.

Aplicación de la econometría espacial para el análisis de la miseria en los municipios del Departamento de Antioquia.

Este artículo comprueba la existencia de autocorrelación espacial al considerar la proporción de personas que viven en situación de miseria en los municipios del departamento de Antioquia, Colombia. Para ello se utiliza el test I de Moran y se propone un algoritmo para descartar la posibilidad de que la dependencia espacial sea espuria. Los resultados demuestran la necesidad de tener en cuenta la econometría espacial para determinar la asignación óptima del gasto social, destinado a intervenir en forma efectiva la situación de miseria en los municipios del departamento de Antioquia

Coordinated pricing and inventory management

This dissertation mainly focuses on coordinated pricing and inventory management problems, where the related background is provided in Chapter 1. Several periodic-review models are then discussed in Chapters 2,3,4 and 5, respectively. Chapter 2 analyzes a deterministic single-product model, where a price adjustment cost incurs if the current selling price is changed from the previous period. We develop exact algorithms for the problem under different conditions and find out that computation complexity varies significantly associated with the cost structure. %Moreover, our numerical study indicates that dynamic pricing strategies may outperform static pricing strategies even when price adjustment cost accounts for a significant portion of the total profit. Chapter 3 develops a single-product model in which demand of a period depends not only on the current selling price but also on past prices through the so-called reference price. Strongly polynomial time algorithms are designed for the case without no fixed ordering cost, and a heuristic is proposed for the general case together with an error bound estimation. Moreover, our illustrates through numerical studies that incorporating reference price effect into coordinated pricing and inventory models can have a significant impact on firms' profits. Chapter 4 discusses the stochastic version of the model in Chapter 3 when customers are loss averse. It extends the associated results developed in literature and proves that the reference price dependent base-stock policy is proved to be optimal under a certain conditions. Instead of dealing with specific problems, Chapter 5 establishes the preservation of supermodularity in a class of optimization problems. This property and its extensions include several existing results in the literature as special cases, and provide powerful tools as we illustrate their applications to several operations problems: the stochastic two-product model with cross-price effects, the two-stage inventory control model, and the self-financing model.

BROMANCE : les paradoxes des stratégies homosociales

Depuis les années 2000, l’apparition du terme Bromance marque la culture populaire américaine. Cette notion est apparue pour définir les amitiés entre hommes au cinéma, à la télévision et sur Internet. Les films de Bromance, caractérisés par une multitude de scènes de déclaration d’amour entre hommes, traduisent bien cette nouvelle façon d’aborder l’amitié au masculin. À travers les définitions de la masculinité dans ces films, l’enjeu de l’hétérosexualité demeure omniprésent. Malgré la fragilisation de certains stéréotypes traditionnels liés au masculin, il n’en demeure pas moins que la notion de «vraie» masculinité persiste et demeure systématiquement liée à l’hétérosexualité des hommes qui partagent cette amitié particulière qu’on appelle Bromance. Dans cette optique, plusieurs stratégies se manifestent pour prouver la masculinité et donc l’hétérosexualité des protagonistes, mais l’une d’entre elles semble être au cœur de ces films. Cette stratégie s’incarne sous la forme d’une compétition entre hommes qui mise sur la capacité à performer un acte conventionnellement associé à l’homosexualité. Sur Internet, des vidéos qui prennent le nom « Gay Chicken » présentent des hommes qui s’embrassent et qui se touchent sans être dérangés ou ébranlés. C’est la capacité à être calme et en contrôle en restant insensible au corps d’un autre homme qui démontrerait le côté inébranlable de son hétérosexualité et donc de sa masculinité. C’est cet esprit du « Gay Chicken » qui se retrouve un peu partout dans l’univers des films de Bromance. Paradoxalement, ces nouveaux «modèles» d’homme doivent pouvoir à la fois incarner une masculinité plus flexible, plus ouverte et sensible, mais doivent également prouver leur virilité. Cette « masculinité contemporaine » brouille les cartes entre ce qui est viril et ce qui ne l’est pas, entre ce qui est féminin et ce qui ne l’est pas et entre ce qui est homosexuel et ce qui ne l’est pas. Les relations homosociales dans le cadre de Bromances présentent alors des opportunités indispensables pour prouver à tous la force de son hétérosexualité. Ce travail de recherche se penchera donc plus précisément sur les paradoxes d’une « masculinité contemporaine » intimement liée à l’orientation hétérosexuelle, par l’entremise de certains films issus de la culture populaire américaine associée à la Bromance. L’objectif est de montrer comment ces films sont des manifestations significatives d’une nouvelle forme d’affirmation identitaire masculine qui passe par des relations homosociales où les tensions et sous-textes homosexuels se multiplient et doivent être réprimés ou invalidés continuellement.