921 resultados para self-organized critical


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Numerical modelling is a valuable tool for simulating the fundamental processes that take place during a heating. The models presented in this paper have enabled a quantitative assessment of the effects of initial pile temperature, pile size and mass and coal particle size on the development of a heating. All of these parameters have a certain criticality in the coal self-heating process.

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El rol de la mujer dentro de la sociedad ha sido y aún es un tema de mucha controversia. Incluso en nuestra sociedad, se suscitan debates sobre si les está permitido a las mujeres ocupar ciertos ámbitos laborales que han estado siempre dominados por una fuerte presencia masculina, como es el caso del ámbito político. Además, en muchos países aún ni siquiera están reconocidos los derechos de las mujeres, y mientras que, en otras culturas, a pesar de que la ley vela por los derechos humanos sin importar la raza, la religión o el género, la realidad es que incluso en las culturas más desarrolladas existe desigualdad de género y estereotipos que afectan el desenvolvimiento de la mujer. Sin embargo, a pesar de que aun la desigualdad de género está presente en la sociedad, es innegable que la situación actual es mucho más positiva para la implicación de las mujeres incluso dentro de ámbitos de la sociedad, que décadas atrás sería impensable, como la política. En esta línea, toda esta situación ha suscitado el interés de muchos investigadores y lingüistas, que han dedicado tiempo a investigaciones sobre las relaciones entre discurso y género, y sobre la representación mediática de mujeres que tienen cierta influencia en el ámbito público, y cómo la desigualdad de género afecta su imagen pública. Si bien es cierto, durante mucho tiempo el ámbito de la política ha estado dominado por presencia masculina, ahora la situación ha cambiado. En las últimas décadas, se ha hecho evidente una gran presencia de mujeres dentro de la política, mujeres que a comparación de la situación vivida décadas atrás, ahora tienen la posibilidad de presentarse incluso como candidatas a la presidencia, como es el caso de Hillary Clinton. En este sentido muchas corrientes feministas han contribuido en gran medida a esta nueva situación. Ahora bien, en vista de toda esta situación, el presente estudio de investigación intentará dar respuesta a las siguientes preguntas. ¿Hasta qué punto los estereotipos de género están aún presentes en la sociedad? ¿La representación mediática de una figura política está realmente basada en su conducta y en su actividad discursiva, o está influida por esquemas e ideas preconcebidas de género? Teniendo en cuenta que hoy en día hay una mayor presencia femenina dentro del ámbito político, una de mis hipótesis iniciales es que la situación de los estereotipos de género ha disminuido. Además, se espera que la forma en la que Hillary Clinton se representa a sí misma como una mujer y como una política esté menos perjudicada por estos esquemas. El objetivo de este estudio es, primeramente, llevar a cabo un análisis sobre diez discursos de Hillary Clinton, desde el 15 de junio de 2015, fecha en la que Hillary Clinton lanzo su candidatura a la presidencia, hasta el 26 de abril de 2016, para a través de este análisis poder identificar como Hillary Clinton se caracteriza a sí misma en sus discursos políticos, y asimismo identificar si los esquemas convencionales sobre género afectan su auto representación. Con este objetivo, el enfoque de este estudio se va a centrar en análisis cuantitativos y cualitativos sobre la frecuencia de palabras, seguido de un análisis crítico del discurso sobre la auto representación de Hillary en sus discursos. Además, siguiendo la línea de investigación de Tannen (1996), se realizará un análisis sobre los usos de los pronombres “nosotros” y “yo”, para adquirir una mayor perspectiva sobre esta situación. Seguidamente, teniendo en cuenta que los medios de comunicación reflejan ideologías sociales, este estudio ha sido también diseñado para analizar diez artículos de noticias sobre los discursos previamente analizados de Hillary Clinton. De esta manera, se examinará si los estereotipos de género están presentes en la representación mediática de Hillary Clinton, para seguidamente analizar si la interpretación mediática de la candidata a la presidencia está realmente relacionada con los discursos analizados o, si por lo contrario están influidos por estereotipos y esquemas de género. Para cumplir con este objetivo, los datos recopilados para este corpus consisten en exactamente diez artículos que reporten sobre los discursos estudiados en el primer análisis, y la actuación de Hillary Clinton. Estos artículos fueron recogidos de cuatro de los periódicos más importantes de los Estados Unidos, que son New York Times, Wall Street Journal, Los Angeles times y The Washington Post. En este caso el análisis estará centrado en la frecuencia de palabras y en el uso de reporting verbs, siguiendo la línea de investigación de Caldas – Coulthard (1995). Se espera que el presente estudio pueda servir para mayores investigaciones sobre cuestiones de género, y de esta manera contribuir a la creación de teorías que puedan explicar mejor la situación de las mujeres dentro de la política. Para finalizar, aún queda mucho que investigar en esta disciplina, e incluso más por descubrir

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Background: The Flexibility of Responses to Self-Critical Thoughts Scale (FoReST) is a questionnaire that was developed to assess whether people can be psychologically flexible when experiencing critical thoughts about themselves. This measure could have important application for evaluating third wave therapies such as Acceptance and Commitment Therapy (ACT) and Compassion Focused therapy (CFT). This study investigated the validity (concurrent, predictive and incremental), internal consistency and factor structure of the FoReST in a sample of people experiencing mental health difficulties. Method: A total of 132 individuals attending Primary Care and Community Mental Health Teams within NHS Greater Glasgow and Clyde (NHS GGC) and Psychological Therapy Teams within NHS Lanarkshire participated in this study. Participants completed a battery of assessments that included the FoReST and related measures of similar constructs (psychological flexibility, self-compassion and self-criticism) and measures of mental health and well-being. A cross-sectional correlational design was used. Results: An Exploratory factor analysis described an interpretable 2-factor structure within the items of the FoReST: unworkable action and experiential avoidance. The FoReST demonstrated good internal consistency ( = .89). Concurrent validity was supported through moderate to strong correlations with similar measures and moderate correlations with other mental health and well-being outcomes. Conclusions: The FoReST appears to be a valid assessment measure for using with individuals experiencing mental health difficulties. This new measure will be of use for practitioners using ACT, CFT and those integrating both, to help monitor the process of change in flexibility and self-critical thinking across therapy. Further longitudinal studies are required to assess the test-retest reliability of the FoReST.

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This study investigates the ‘self’ of six Irish working-class women, all parenting alone and all returned to the field of adult education. Bourdieu’s concepts of habitus, field and capital are the backdrop for the study of the ‘self’, which is viewed through his lens. This study commenced in September 2012 and concluded in August 2014, in a small urban educational setting in an Irish city. All of the women in the study are single parents, most of them did not complete second level education, and none of them had experienced adult or third level education. Their ages vary from 30 to 55 years. The study pursues the women’s motivations for returning to education, the challenges they faced throughout the journey, and their experiences, views and perspectives of Adult Education. The methodology chosen for this research is critical eethnography, and as an emerging ethnographer, I was able to view the phenomena from both an emic (inside) and an etic (outside) perspective. The critically oriented approach is a branch of qualitative research. It is a holistic and humanistic approach that is cyclical and reflective. The critical ethnographic case studies that developed are theoretically framed in critical theory and critical pedagogy. The data is collected from classroom observations (recorded in a journal) and interviews (both individual and group). The women's life experiences inform their sense of self and their capital reserves derive from their experience of habitus. It also attempts to understand the delivery of the programmes and how it can impact the journey of the adult learners. The analysis of the interviews, observations, field notes and reflective journals demonstrate what the women have to say about their new journey in adult education. This crucial information informs best practice for adult education programmes. This study also considers the complexity of habitus and the many forms of capital. The theme of adults returning to education and their disposition to this is one of the major themes of this study. Findings reflect this uncertainty but also underline how the women unshackled themselves of some of the constraints of a restricted view of self. Witnessing this new habitus forming was the core of their transformational possibility becoming real. The study provides a unique contribution to knowledge as it utilises Bourdieuian concepts and theories, not only as theoretical tools but as conceptual tools for analysis. The study examined transformative pedagogy in the field of adult education and it offers important recommendations for future policy and practice.

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Wormlike micelles formed by the addition to cetyltrimethylammonium bromide (CTAB) of a range of aromatic cosolutes with small molecular variations in their structure were systematically studied. Phenol and derivatives of benzoate and cinnamate were used, and the resulting mixtures were studied by oscillatory, steady-shear rheology, and the microstructure was probed by small-angle neutron scattering. The lengthening of the micelles and their entanglement result in remarkable viscoelastic properties, making rheology a useful tool to assess the effect of structural variations of the cosolutes on wormlike micelle formation. For a fixed concentration of CTAB and cosolute (200 mmol L(-1)), the relaxation time decreases in the following order: phenol > cinnamate> o-hydroxycinnamate > salicylate > o-methoxycinnamate > benzoate > o-methoxybenzoate. The variations in viscoelastic response are rationalized by using Mulliken population analysis to map out the electronic density of the cosolutes and quantify the barrier to rotation of specific groups on the aromatics. We find that the ability of the group attached to the aromatic ring to rotate is crucial in determining the packing of the cosolute at the micellar interface and thus critically impacts the micellar growth and, in turn, the rheological response. These results enable us for the first time to propose design rules for the self-assembly of the surfactants and cosolutes resulting in the formation of wormlike micelles with the cationic surfactant CTAB.

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We have considered a Bose gas in an anisotropic potential. Applying the the Gross-Pitaevskii Equation (GPE) for a confined dilute atomic gas, we have used the methods of optimized perturbation theory and self-similar root approximants, to obtain an analytical formula for the critical number of particles as a function of the anisotropy parameter for the potential. The spectrum of the GPE is also discussed.

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Consider N sites randomly and uniformly distributed in a d-dimensional hypercube. A walker explores this disordered medium going to the nearest site, which has not been visited in the last mu (memory) steps. The walker trajectory is composed of a transient part and a periodic part (cycle). For one-dimensional systems, travelers can or cannot explore all available space, giving rise to a crossover between localized and extended regimes at the critical memory mu(1) = log(2) N. The deterministic rule can be softened to consider more realistic situations with the inclusion of a stochastic parameter T (temperature). In this case, the walker movement is driven by a probability density function parameterized by T and a cost function. The cost function increases as the distance between two sites and favors hops to closer sites. As the temperature increases, the walker can escape from cycles that are reminiscent of the deterministic nature and extend the exploration. Here, we report an analytical model and numerical studies of the influence of the temperature and the critical memory in the exploration of one-dimensional disordered systems.

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The concentration of hydrogen peroxide is an important parameter in the azo dyes decoloration process through the utilization of advanced oxidizing processes, particularly by oxidizing via UV/H2O2. It is pointed out that, from a specific concentration, the hydrogen peroxide works as a hydroxyl radical self-consumer and thus a decrease of the system`s oxidizing power happens. The determination of the process critical point (maximum amount of hydrogen peroxide to be added) was performed through a ""thorough mapping"" or discretization of the target region, founded on the maximization of an objective function objective (constant of reaction kinetics of pseudo-first order). The discretization of the operational region occurred through a feedforward backpropagation neural model. The neural model obtained presented remarkable coefficient of correlation between real and predicted values for the absorbance variable, above 0.98. In the present work, the neural model had, as phenomenological basis the Acid Brown 75 dye decoloration process. The hydrogen peroxide addition critical point, represented by a value of mass relation (F) between the hydrogen peroxide mass and the dye mass, was established in the interval 50 < F < 60. (C) 2007 Elsevier B.V. All rights reserved.

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Effective solids suspension is a necessary precondition for particle collection, and solids suspension is largely dependent on the hydrodynamics of the flotation cell. This study attempted to correlate the status of the suspension of apatite particles of different sizes in a Denver laboratory flotation cell versus the impeller rotational speed (N) adopted to operate the machine. The latter variable (N) influences the impeller capacity to lift the particles from the bottom of the tank and also to disperse them throughout the volume of the vessel. Such an impeller capacity can be characterized by the critical impeller speed for the accomplishment of solids off-bottom suspension (N(z)) and also by the velocity of the radial water flow discharged by the impeller (U) divided by the particle terminal settling velocity (U(s)). This way, the status of the suspension of apatite particles inside the flotation cell can be characterized by one of three categories: ""segregation"" (N/N(2) < 0.60 and U(s)/U > 0.08); ""suspension"" (0.60 <= N/N(2) < 1 and 0.06 < U(s)/U < 0.10); and ""dragging"" (N/N(2) >= 1 and U(s)/U <= 0.03). The range of impeller rotational speed (N), which was able to suspend the finest particles (D(p) = 90,mu m), was unable to suspend the coarsest particles (D(P) = 254 mu m). Conversely, the high value of N (N > 1,300 rpm), which is adequate to suspend the coarsest particles, may promote the entrainment of the finest particles to the froth layer.

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There are many industrial advantages of using mechanical multi-oxides mixtures to obtain ceramic parts by electrophoretic deposition (EPD). This is mainly because one could avoid complex chemical synthesis routes to achieve a desirable composition. However, EPD of these suspensions is not an easy task as well since many different surfaces are present, leading to unexpected suspension behavior. The particles surface potentials and interactions can, however, be predicted by an extension of the DLVO theory. Using this theory, one can control the suspension properties and particles distribution. The objective of this work was to apply the colloidal chemistry theories to promote the formation of a heterocoagulation between ZrO(2) and Y(2)O(3) particles in ethanol suspension to achieve a suitable condition for EPD. After identifying a condition where those particles had opposite surface charges and adequate relative sizes, heterocoagulation was observed at operational pH 7.5, generating an organized agglomerate with ZrO(2) particles surrounding Y(2)O(3), with a net zeta potential of -16.6 mV. Since the agglomerates were stable, EPD could be carried out and homogeneous deposits were obtained. The deposited bodies were sintered at 1600 A degrees C for 4 h and partially stabilized ZrO(2) could be obtained without traces of Y(2)O(3) second phases.

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The critical interaction initiating and perhaps perpetuating rheumatoid arthritis (RA) is the presentation of arthritogenic antigen to autoreactive T cells. In contrast to many organ-specific autoimmune diseases, no candidate autoantigens have yet been confirmed for RA. Here, Ranjeny Thomas and Peter Lipsky examine the role of dendritic cells in autoimmune disease, leading to the hypothesis that activation of T cells by endogenous self-peptides may be sufficient to initiate RA.