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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.
11

Friends with Benefits: Other Regard in Epicurean Ethics

Baird, William P 11 August 2011 (has links)
Friendship and hedonism are both major components of Epicureanism. I attempt to relieve the tension that seems to follow from endorsing both of these. I argue that Epicurean friendships require valuing a friend’s well-being in the same way as one’s own and that embarking on such friendships is what David Schmidtz terms a maieutic end – one that is achieved by taking on a new set of ends. This conception fits with other-regarding concern that is espoused throughout the Epicurean texts discussing friendship and, as I argue, remains consistent with other psychological and ethical commitments of Epicureanism.
12

Friends with Benefits: Other Regard in Epicurean Ethics

Baird, William P 11 August 2011 (has links)
Friendship and hedonism are both major components of Epicureanism. I attempt to relieve the tension that seems to follow from endorsing both of these. I argue that Epicurean friendships require valuing a friend’s well-being in the same way as one’s own and that embarking on such friendships is what David Schmidtz terms a maieutic end – one that is achieved by taking on a new set of ends. This conception fits with other-regarding concern that is espoused throughout the Epicurean texts discussing friendship and, as I argue, remains consistent with other psychological and ethical commitments of Epicureanism.
13

Moderating Factors of Co-occurring GD/IGD and ENDS Use among College Students

Mitchell, Hannah G., Kromash, Rachelle H., Ginley, Meredith K. 01 April 2021 (has links)
Introduction: Research has found extensive similarities between symptoms of gaming disorder/Internet gaming disorder (GD/IGD) and symptoms of other addictive disorders, including the presence of cravings, tolerance, and inability to stop despite adverse consequences (Müller & Montag, 2017). Significant associations between GD/IGD and financial strain, occupational difficulties, sleep deprivation, malnutrition, obesity, and the development and/or exacerbation of other mental illness have been found, contributing to growing concern over the detrimental impact of GD/IGD (Kohorst et al., 2018). Video gaming is also associated with increased use of substances, including nicotine as found in electronic nicotine delivery systems (ENDS; Cranwell et al., 2016). The harmful consequences of ENDS use may exacerbate the health risks associated with GD/IGD, especially in connection to sleep, nutrition, and mental health. There is extensive overlap between the demographic and psychosocial characteristics of typical video gamers and typical users of ENDS, including being young, male, highly impulsive, sensation-seeking, and having a diagnosis of attention-deficit hyperactivity disorder (ADHD), which may account for the rates of concurrent dependence (Von der Heiden et al., 2019; Mathews, 2019). However, definitive characteristics of individuals demonstrating symptoms of both GD/IGD and ENDS dependency remain unknown. The present study aims to explore the demographic and psychological associations of co-occurring symptoms of GD/IGD and ENDS dependency. Method:Participants (n = 2,174) were college students age 18-24 (M=19.25) recruited as part of a multi-university study examining psychological variables within young adults. Participants completed a battery of self-report questions assessing for demographic characteristics, symptoms of ADHD, and level of impulsivity and sensation seeking as measured by the Adult ADHD Self-Report Scale, Brief Sensation Seeking Scale, and Barratt Impulsiveness Scale Version 11, respectively. ENDS dependency was evaluated through the PROMIS E-cigarette Dependence Scale, and GD/IGD was measured by the Video Game Dependency Scale. Pearson correlations, chi-square tests, MANCOVAS, and moderation analyses were used to evaluate this data. Results:Results found that 7.3% of the sample met criteria for probable ENDS dependency, 4.7% of the sample endorsed symptoms of GD/IGD dependency, and 1.4% of the sample endorsed both dependencies. Age, gender, and race/ethnicity were all associated with increased risk of concurrent GD/IGD and ENDS dependency. The moderating effect of ADHD symptoms on the relation between GD/IGD and ENDS dependency was significant, ΔR2 = .067, F(1, 1036) = 24.75, p < .001, indicating that the relation between GD/IGD and ENDS dependency was stronger when participants endorsed more symptoms of ADHD. Impulsivity and sensation seeking also had significant interaction effects on the relation between ENDS dependency and GD/IGD. Conclusion:Ultimately, there is ample evidence that ENDS dependency and GD/IGD occur at significant levels on college campuses. Heightened impulsivity and sensation seeking and the diagnosis of ADHD significantly correspond with increased rates of GD/IGD and ENDS dependency. These results are supported by prior research findings that impulsivity and sensation seeking are risk factors for many behavioral health concerns, including engagement in risky sexual behaviors and substance addiction. Future research examining protective factors and treatment of co-occurring GD/IGD and ENDS dependency is warranted. References: Cranwell, J., Whittamore, K., Britton, J., & Leonardi-Bee, J. (2016). Alcohol and tobacco content in UK video games and their association with alcohol and tobacco use among young people. Cyberpsychology, Behavior and Social Networking, 19(7), 426-434. https://doi.org/10.1089/cyber.2016.0093 Kohorst, M. A., Warad, D. M., Nageswara Rao, A. A., & Rodriguez, V. (2018). Obesity, sedentary lifestyle, and video games: The new thrombophilia cocktail in adolescents. Pediatric Blood & Cancer, 65(7), e27041. Mathews, C. L., Morrell, H. E. R., & Molle, J. L. (2019). Video game addiction, ADHD symptomatology, and video game reinforcement. The American Journal of Drug and Alcohol Abuse, 45(1), 67-76. https://doi.org/10.1080/00952990.2018.1472269 Müller, M., & Montag, C. (2017). The relationship between internet addiction and alcohol consumption is influenced by the smoking status in male online video gamers. Clinical Neuropsychiatry: Journal of Treatment Evaluation, 14(1), 34–43. Von der Heiden, J. M., Braun, B., Müller, K. W., & Egloff, B. (2019). The association between video gaming and psychological functioning. Frontiers in Psychology, 10, 17-31. https://doi.org/10.3389/fpsyg.2019.01731
14

The post-buckled coupled mode interaction behaviour of thin-walled members in compression using finite element simulation

Yidris, Noorfaizal January 2012 (has links)
The work of this thesis sets out to give a clearer in-depth understanding of the failure mechanics of thin-walled compression members which are associated with complex interactions between the different buckling modes during the loading process. This thesis employs the finite element method in order to examine the effect of the modelling techniques imposed at the section junctions of short struts and to investigate the influence of the local and global end conditions with regard to support and loading on the compressive response of various sections, i.e. I-sections, plain channel sections, box-sections, and lipped channel sections. The thesis also details appropriate finite element modelling strategies and solution procedures taking due account of the influence of material nonlinearity and geometrical imperfections for the determination of the coupled mode interactive response of thin-walled compression members. A detailed account of the complete loading history of the compression members from the beginning of loading through to final collapse is given in the thesis. This involves elastic local buckling, nonlinear elastic and elasto-plastic post-buckling interaction behaviour and yield propagation leading to the development of an appropriate failure mechanism which causes final collapse and unloading. A new finite element modelling strategy has been developed in the thesis with particular reference to being able to deal with the classical assumption of the stress-free in-plane boundary conditions existing at the section junctions of short length strut members during post-local buckling. Also, for fixed-ended columns, with particular reference to singly-symmetric plain channel sections, it has been shown that column deflections are initiated from the onset of local buckling for the case of the constituent plate elements of the section being locally rotationally constrained at their ends. Such columns should not therefore be considered as an overall bifurcation problem of the locally buckled member. In the case of the pinned and fixed-ended boundary conditions of the columns, the finite element simulations are shown to be able to accurately describe the rather different complex failure mechanics with a high degree of imperfection sensitivity being shown to be in evidence for the pin-ended case. Considerably good agreement has been shown to occur with the independent simulations of other researchers using the finite strip method of analysis, with the analytical solution procedures of others and with the findings from independent test work and this has provided confidence in the viability and usefulness of the modelling strategies and solution procedures developed in this thesis.
15

20–25 Gbit/s low-power inductor-less single-chip optical receiver and transmitter frontend in 28 nm digital CMOS

Szilàgyi, Làszlò, Belfiore, Guido, Henker, Ronny, Ellinger, Frank 29 May 2020 (has links)
The design of an analog frontend including a receiver amplifier (RX) and laser diode driver (LDD) for optical communication system is described. The RX consists of a transimpedance amplifier, a limiting amplifier, and an output buffer (BUF). An offset compensation and common-mode control circuit is designed using switched-capacitor technique to save chip area, provides continuous reduction of the offset in the RX. Active-peaking methods are used to enhance the bandwidth and gain. The very low gate-oxide breakdown voltage of transistors in deep sub-micron technologies is overcome in the LDD by implementing a topology which has the amplifier placed in a floating well. It comprises a level shifter, a pre-amplifier, and the driver stage. The single-chip frontend, fabricated in a 28 nm bulk-digital complementary metal–oxide–semiconductor (CMOS) process has a total active area of 0.003 mm² , is among the smallest optical frontends. Without the BUF, which consumes 8 mW from a separate supply, the RX power consumption is 21 mW, while the LDD consumes 32 mW. Small-signal gain and bandwidth are measured. A photo diode and laser diode are bonded to the chip on a test-printed circuit board. Electro-optical measurements show an error-free detection with a bit error rate of 10⁻¹² at 20 Gbit/s of the RX at and a 25 Gbit/s transmission of the LDD.
16

Dualidade de Poincaré e invariantes cohomológicos

Cellini, Caroline Paula [UNESP] 31 March 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-03-31Bitstream added on 2014-06-13T19:19:04Z : No. of bitstreams: 1 cellini_cp_me_sjrp.pdf: 781641 bytes, checksum: 70ed1b385d132f8255370c0014be09b4 (MD5) / Neste trabalho são abordados alguns aspectos da teoria de dualidade. Ele pode ser dividido em três partes principais. Na primeira demonstramos o teorema de Dualidade de Poincaré para variedades (sem bordo) orientáveis. Para tanto, fez-se necessário o uso do limite direto e cohomologia com suporte compacto. Na segunda definimos grupos de dualidade, em particular, grupo de dualidade de Poincaré, apresentamos alguns resultados e observações sobre a relação existente entre tais grupos e os grupos fundamentais de variedades asféricas fechadas, que é ainda um problema em aberto. Finalmente, alguns resultados envolvendo invariantes cohomológicos ends e grupos de dualidade são apresentados. / In this work we consider some aspects of duality theory. It can be divided in three principal parts. In the first we prove the Poincaré Duality theorem for orientable manifolds (without boundary). For that, it is necessary the use of the direct limit and cohomology with compact supports. In the second part we de¯ne duality groups, in particular, Poincaré duality groups, we introduce some results and observations about the relationship between such groups and fundamental groups of aspherical closed manifolds, that still is an open problem. Finally, some results envolving the cohomological invariant ends and duality groups are presented.
17

Difeomorfismos do plano com número de rotação de fins primos irracional / Diffeomorphisms of the plane with irrational prime ends rotation number

Barboza, Diego Pereira 26 February 2019 (has links)
O principal objetivo desta tese é estudar o número de rotação de fins primos de homeomorfismos planares que pertencem a uma classe de homeomorfismos H. Tal número de rotação é devido à Carathéordory e semelhante à teoria de Poincaré para homeomorfismos do crculo. Para todo irracional (0, 1), denotando por (h, U ) o número de rotação de fins primos de h H em U , com U a bacia de repulsão do infinito, construiremos um homeomorfismo h H satisfazendo (h, U ) = e que possui uma sela periódica com intersecção homoclnica transversal em U . Além disso, quando h é de classe C 2 e det(Dh| x ) < 1 em todo ponto, mostraremos que existe ponto periódico acessvel em U se, e somente se, (h, U ) é racional. Também será provado que, quando h é uma ferradura de Smale, o número de rotação (h, U ) é racional. Finalizando, provaremos que se for possvel a existência de um difeomorfismo C r , r 1, em um conjunto genérico a ser definido, com U = W u (p) para p uma sela homoclnica com intersecção transversal e tal que o número de rotação (h, U ) é irracional, necessariamente, h deve satisfazer uma propriedade que não é válida para ferraduras de Smale. / The main objective of this thesis is to study the prime ends rotation number of planar homeomorphisms belonging to a class of homeomorphisms H. Such rotation number is due to Carathéordory and similar to the Poincarés theory of homeomorphisms of the circle. For all irrational (0, 1), denoting by (h, U ) the prime end rotation number of h H in U , with U the infinity repulsion basin, we will construct a homeomorphism h H satisfying (h, U ) = and having a homoclinic saddle with transverse intersection in U . Also, when h is class C 2 and det (Dh| x ) < 1 at every point, we will show that there is accessible periodic point in U if, and only if, (h, U ) is rational. It will also be proved that when h is a Smales horseshoe, the rotation number (h, U ) is rational. To conclude, we will prove that if there exists a C r -diffeomorphism, in a generic set to be defined, with U = W u (p) for a saddle point p with transverse homoclinal intersection and such that the rotation number (h, U ) is irrational, then h must satisfy a property that is not valid for Smales horseshoes.
18

Coarse Cohomology with twisted Coefficients

Hartmann, Elisa 25 February 2019 (has links)
No description available.
19

Moral e política: o princípio da autonomia e o reino dos fins na Filosofia Kantiana / Moral and politics: the principle of autonomy and the kingdom of ends

Ruas, Gonçalo Nunes Barrilaro 06 February 2015 (has links)
O estudo do princípio da autonomia, conceito central na filosofia moral de Kant, permite compreender a origem da lei moral. A fórmula da autonomia prescreve que a lei moral é fruto da vontade e não depende de fatores externos: nós somos colegisladores de uma lei a que nos submetemos. A tese da unidade do imperativo categórico assevera que o imperativo categórico é uno e apenas um. Portanto, ao aplicar-se o imperativo categórico na política através da fórmula da lei universal estáse efetivamente a aplicar o princípio supremo da moralidade num contexto sócio político. A fórmula do reino dos fins faz com que esta associação seja mais presente, principalmente através da analogia entre súditos e soberanos de uma lei moral, que na política se dá através da relação entre chefe de Estado e cidadãos. Com o conceito de \'reino dos fins\' dá-se um passo em frente e a ideia de co-legislação é aplicada, segundo cremos, por um processo sócio-político na Paz Perpétua. Por sua vez, expõese o pensamento de vários autores que interpretam conceitos morais de um ponto de vista político. No entanto, nos afastamos dessa interpretação por reconhecermos que na Filosofia Moral kantiana não existe uma evidência suficiente para essa asserção. A relação é, por isso, inversa à proposta pela tradição construtivista: a moralidade está presente na Filosofia Política. Ela pode, com efeito, coincidir completamente com a política quando se trata dos princípios fundamentais da política. Ou pode servir como um impedimento a certas ações que, embora não sejam de teor moral, estejam em contradição com ela. Tal como acontece com os imperativos hipotéticos. A razão prudencial, pragmática ou técnica, deve dobrar seus joelhos perante a razão prática pura. Propõe-se, assim, um paralelo com conceitos desenvolvidos na Paz Perpétua, designadamente com a ideia de um modo de governo republicano (constituição republicana), onde os seus membros têm de participar de uma legislação, e com o político moral, considerado o agente responsável por aplicar a moral (razão prática pura). / The study of the principle of autonomy, a central concept in Kant\'s moral philosophy, allow us to understand the origin of the moral law. The formula of autonomy dictates that the moral law is the result of the will and does not depend on external factors: we are co-legislators of a law that we submit to ourselves. The thesis of the unity of the categorical imperative asserts that the categorical imperative is one and only one. Therefore, when applying the categorical imperative in politics through the formula of universal law is being effectively applied by the supreme principle of morality in a sociopolitical context. The formula of the kingdom of ends makes this association more present, mainly through the analogy between sovereigns and subjects of a moral law, which in politics is through the relationship between the head of state and citizens. With the concept of \'kingdom of ends\' a step ahead is done and the idea of co-legislation is applied, giving us, we believe, by a socio-political process in the Perpetual Peace. In turn, we expose the thought of many authors who interpret moral concepts from a political point of view. However, we drifted apart this interpretation because we recognize that in Kant\'s Moral Philosophy there isn\'t a strong evidence for this assertion. The relationship is, therefore, reverse to the proposal by the Constructivist tradition: the morality is present in Political Philosophy. It may, in fact, match completely with the politics when it comes to the fundamental principles of politics. Or can serve as a constraint to certain actions that, while not of moral content, are in contradiction with it. As occurs with the hypothetical imperatives. The prudential reason, pragmatic or technical, should double their \'knees\' before the pure practical reason. Therefore we propose a parallel with concepts developed in Perpetual Peace, namely the idea of a republican form of government (republican constitution), where its members have to participate in a common legislation, and the moral politician, considered the agent responsible for applying morale (pure practical reason).
20

Planejamento probabilístico com becos sem saída / Probabilistic planning with dead-ends

Simão, Thiago Dias 06 March 2017 (has links)
Planejamento probabilístico lida com a tomada de decisão sequencial em ambientes estocásticos e geralmente é modelado por um Processo de Decisão Markoviano (Markovian Decision Process - MDP). Um MDP modela a interação entre um agente e o seu ambiente: em cada estágio, o agente decide executar uma ação, com efeitos probabilísticos e um certo custo, que irá produzir um estado futuro. O objetivo do agente MDP é minimizar o custo esperado ao longo de uma sequência de escolhas de ação. O número de estágios que o agente atua no ambiente é chamado de horizonte, o qual pode ser finito, infinito ou indefinido. Um exemplo de MDP com horizonte indefinido é o Stochastic Shortest Path MDP (SSP MDP), que estende a definição de MDP adicionando um conjunto de estados meta (o agente para de agir ao alcançar um estado meta). Num SSP MDP é feita a suposição de que é sempre possível alcançar um estado meta a partir de qualquer estado do mundo. No entanto, essa é uma suposição muito forte e que não pode ser garantida em aplicações práticas. Estados a partir dos quais é impossível atingir a meta são chamados de becos-sem-saída. Um beco-sem-saída pode ser evitável ou inevitável (se nenhuma política leva do estado inicial para a meta com probabilidade um). Em trabalhos recentes foram propostas extensões para SSP MDP que permitem a existência de diferentes tipos de beco-sem-saída, bem como algoritmos para resolvê-los. No entanto, a detecção de becos-sem-saída é feita utilizando: (i) heurísticas que podem falhar para becos-sem-saída implícitos ou (ii) métodos mais confiáveis, mas que demandam alto custo computacional. Neste projeto fazemos uma caracterização formal de modelos de planejamento probabilístico com becos-sem-saída. Além disso, propomos uma nova técnica para detecção de becos-sem-saída baseada nessa caracterização e adaptamos algoritmos de planejamento probabilístico para utilizarem esse novo método de detecção. Os resultados empíricos mostram que o método proposto é capaz de detectar todos os becos-sem-saída de um dado conjunto de estados e, quando usado com planejadores probabilísticos, pode tornar esses planejadores mais eficientes em domínios com becos-sem-saída difíceis de serem detectados / Probabilistic planning deals with sequential decision making in stochastic environments and is modeled by a Markovian Decision Process (MDP). An MDP models the interaction between an agent and its environment: at each stage, the agent decides to execute an action, with probabilistic effects and a certain cost which produces a future state. The purpose of the MDP agent is to minimize the expected cost along a sequence of choices. The number of stages that the agent acts in the environment is called horizon, which can be finite, infinite or undefined. An example of MDP with undefined horizon is the Stochastic Shortest Path MDP, which extends the definition of MDP by adding a set of goal states (the agent stops acting after reaching a goal state). In an SSP MDP the assumption is made that it is always possible to achieve a goal state from every state of the world. However, this is a very strong assumption and cannot be guaranteed in practical applications. States from which it is impossible to reach the goal are called dead-ends. A dead-end may be avoidable or unavoidable (when no policy leads from the initial state to the goal with probability one). Recent work has proposed extensions to SSP MDP that allow the existence of different types of dead-ends as well as algorithms to solve them. However, the detection of dead-end is done using: (i) heuristics that may fail to detect implicitly dead-ends or (ii) more reliable methods that require a high computational cost. In this project we make a formal characterization of probabilistic planning models with dead-ends. In addition, we propose a new technique for dead-end detection based on this characterization and we adapt probabilistic planning algorithms to use this new detection method. The empirical results show that the proposed method is able to detect all dead-ends of a given set of states and, when used withprobabilistic planners, can make these planners more efficient in domains with difficult to detect dead-ends.

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