939 resultados para INFORMATION PROCESSING


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This dissertation covers two separate topics in statistical physics. The first part of the dissertation focuses on computational methods of obtaining the free energies (or partition functions) of crystalline solids. We describe a method to compute the Helmholtz free energy of a crystalline solid by direct evaluation of the partition function. In the many-dimensional conformation space of all possible arrangements of N particles inside a periodic box, the energy landscape consists of localized islands corresponding to different solid phases. Calculating the partition function for a specific phase involves integrating over the corresponding island. Introducing a natural order parameter that quantifies the net displacement of particles from lattices sites, we write the partition function in terms of a one-dimensional integral along the order parameter, and evaluate this integral using umbrella sampling. We validate the method by computing free energies of both face-centered cubic (FCC) and hexagonal close-packed (HCP) hard sphere crystals with a precision of $10^{-5}k_BT$ per particle. In developing the numerical method, we find several scaling properties of crystalline solids in the thermodynamic limit. Using these scaling properties, we derive an explicit asymptotic formula for the free energy per particle in the thermodynamic limit. In addition, we describe several changes of coordinates that can be used to separate internal degrees of freedom from external, translational degrees of freedom. The second part of the dissertation focuses on engineering idealized physical devices that work as Maxwell's demon. We describe two autonomous mechanical devices that extract energy from a single heat bath and convert it into work, while writing information onto memory registers. Additionally, both devices can operate as Landauer's eraser, namely they can erase information from a memory register, while energy is dissipated into the heat bath. The phase diagrams and the efficiencies of the two models are solved and analyzed. These two models provide concrete physical illustrations of the thermodynamic consequences of information processing.

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The approximation lemma is a simplification of the well-known take lemma, and is used to prove properties of programs that produce lists of values. We show how the approximation lemma, unlike the take lemma, can naturally be generalised from lists to a large class of datatypes, and present a generic approximation lemma that is parametric in the datatype to which it applies. As a useful by-product, we find that generalising the approximation lemma in this way also simplifies its proof.

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A behavioral mind-set refers to the effect of performing a behavior in one situation (e.g., deciding which animals jump higher, dolphins or sea lions) on the likelihood of performing a conceptually similar behavior in subsequent, unrelated situations (e.g., deciding which of two candies to purchase). It reflects the activation and persistence of procedural knowledge. My dissertation circumscribes the construct of a behavioral mind-set and proposes a theoretical framework describing how mind-sets operate as well as their cognitive and motivational determinants. Three sets of studies investigated the role of mind-sets in different domains. The first set of studies explored the influence of making comparative judgments on subsequent decision making. Specifically, I found that making comparative judgment in one situation activates a which-to-buy mind-set that increases the willingness to decide which of two products to purchase in a later situation without considering the option of not buying anything at all. This mind-set can be activated not only by stating preferences for one of two products but also by comparing the relative attractiveness of wild animals, comparing the animals with respect to physical attributes, and estimating how similar one object is to another. Furthermore, the mind-set, once activated, influences not only purchase intentions in hypothetical situations but the actual decisions to purchase one of different types of products that are on sale after the experiment. The second set of studies investigated whether generating supportive elaborations or counterarguments in one situation will influence people’s tendency to engage in similar behavior in a subsequent, unrelated situation. I found that making supportive elaborations in one situation gives rise to a bolstering mind-set that, once activated, increases participants’ disposition to generate supportive thoughts in response to persuasive communications that they receive later and, therefore, increases the effectiveness of persuasion. Correspondingly, generating opposing arguments in an initial situation activates a counterarguing mind-set that increases the tendency to argue against the persuasive communications and decreases its effectiveness. However, a counterarguing mind-set may increase the effectiveness of persuasion if the messages are difficult to be refuted. The third set of studies distinguished between the influence of motivation on consumer behavior and the influence of a mind-set that is activated by this motivation. Specifically, I found that appetitive motivation, which naturally increases people’s tendency to acquire food products, can give rise to a cognition-based acquisition mind-set that increases people’s disposition to acquire non-food products as well. This acquisition mind-set may persist even when the appetitive motivation that gave rise to it is satiated by eating. Moreover, the disposition to acquire non-food products is not mediated by the products’ attractiveness. The studies suggest that motivation and mind-sets may independently influence consumers’ evaluation of a product and their dispositions to acquire it. Motivation is more likely to influence product evaluations whereas a mind-set is more likely to influence consumers’ acquisition dispositions. In summary, a behavioral mind-set can be activated in the process of performing a behavior. And the mind-set may influence people’s subsequent behaviors in unrelated situations in which the activated procedure is applicable. Moreover, motivation to engage in one behavior could also elicit a cognition-based mind-set, which may change people’s subsequent behaviors.

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LOPES-DOS-SANTOS, V. , CONDE-OCAZIONEZ, S. ; NICOLELIS, M. A. L. , RIBEIRO, S. T. , TORT, A. B. L. . Neuronal assembly detection and cell membership specification by principal component analysis. Plos One, v. 6, p. e20996, 2011.

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The biological immune system is a robust, complex, adaptive system that defends the body from foreign pathogens. It is able to categorize all cells (or molecules) within the body as self-cells or non-self cells. It does this with the help of a distributed task force that has the intelligence to take action from a local and also a global perspective using its network of chemical messengers for communication. There are two major branches of the immune system. The innate immune system is an unchanging mechanism that detects and destroys certain invading organisms, whilst the adaptive immune system responds to previously unknown foreign cells and builds a response to them that can remain in the body over a long period of time. This remarkable information processing biological system has caught the attention of computer science in recent years. A novel computational intelligence technique, inspired by immunology, has emerged, called Artificial Immune Systems. Several concepts from the immune have been extracted and applied for solution to real world science and engineering problems. In this tutorial, we briefly describe the immune system metaphors that are relevant to existing Artificial Immune Systems methods. We will then show illustrative real-world problems suitable for Artificial Immune Systems and give a step-by-step algorithm walkthrough for one such problem. A comparison of the Artificial Immune Systems to other well-known algorithms, areas for future work, tips & tricks and a list of resources will round this tutorial off. It should be noted that as Artificial Immune Systems is still a young and evolving field, there is not yet a fixed algorithm template and hence actual implementations might differ somewhat from time to time and from those examples given here.

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TORT, A. B. L. ; SCHEFFER-TEIXEIRA, R ; Souza, B.C. ; DRAGUHN, A. ; BRANKACK, J. . Theta-associated high-frequency oscillations (110-160 Hz) in the hippocampus and neocortex. Progress in Neurobiology , v. 100, p. 1-14, 2013.

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In economics of information theory, credence products are those whose quality is difficult or impossible for consumers to assess, even after they have consumed the product (Darby & Karni, 1973). This dissertation is focused on the content, consumer perception, and power of online reviews for credence services. Economics of information theory has long assumed, without empirical confirmation, that consumers will discount the credibility of claims about credence quality attributes. The same theories predict that because credence services are by definition obscure to the consumer, reviews of credence services are incapable of signaling quality. Our research aims to question these assumptions. In the first essay we examine how the content and structure of online reviews of credence services systematically differ from the content and structure of reviews of experience services and how consumers judge these differences. We have found that online reviews of credence services have either less important or less credible content than reviews of experience services and that consumers do discount the credibility of credence claims. However, while consumers rationally discount the credibility of simple credence claims in a review, more complex argument structure and the inclusion of evidence attenuate this effect. In the second essay we ask, “Can online reviews predict the worst doctors?” We examine the power of online reviews to detect low quality, as measured by state medical board sanctions. We find that online reviews are somewhat predictive of a doctor’s suitability to practice medicine; however, not all the data are useful. Numerical or star ratings provide the strongest quality signal; user-submitted text provides some signal but is subsumed almost completely by ratings. Of the ratings variables in our dataset, we find that punctuality, rather than knowledge, is the strongest predictor of medical board sanctions. These results challenge the definition of credence products, which is a long-standing construct in economics of information theory. Our results also have implications for online review users, review platforms, and for the use of predictive modeling in the context of information systems research.

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Tutkimuksessa selvitetään turkulaisten peruskoulun päättöluokkalaisten urapohdintaeroja ja sitä, miten oppilaiden arviot opettajien ja oppilaanohjaajien toteuttamasta ohjauksesta ovat yhteydessä heidän urapohdintaansa. Tutkimuksen kohdejoukkona ovat ensi sijassa yleisopetusta antavien suomenkielisten peruskoulujen yhdeksäsluokkalaiset. Tutkimus on poikkileikkaustutkimus, jossa tarkastellaan oppilaiden kokemuksia ohjauksen saatavuudesta ja hyödyllisyydestä sekä urapohdinnasta peruskoulun päättyessä. Tutkimusaineisto koottiin yhteishaun jälkeen huhti–toukokuussa 2014. Vuoden 2004 perusopetuksen opetussuunnitelman perusteista johdettujen väittämien avulla selitetään urapohdinta-mittarin sisältämien muuttujien vaihtelua. Taustamuuttujina käytetään oppilaiden koti- ja koulutaustaa. Urapohdinta-mittari on johdettu CIP-teoriasta (Cognitive Information Processing) ja muokattu CTI-mittarista (Career Thoughts Inventory). Tutkimusaineisto (N = 887) on koottu Webropol-kyselyn avulla. Oppilaiden urapohdintaa mitattiin neljän summamuuttujien avulla. Mittariston 48 väittämästä muodostettiin urapohdinta-summamuuttuja. Tämän lisäksi urapohdinnan osa-alueita arvioitiin sitoutuminen-, epävarmuus- ja konflikti-summamuuttujan avulla. Sitoutuminen-summamuuttuja mittasi sitä, miten vaikeaksi oppilas koki yhteen ura- ja jatkokoulutusvalintaan sitoutumisen. Epävarmuus-summamuuttuja mittasi päätöksenteon epävarmuutta ja konflikti-summamuuttuja vaikeutta tasapainoilla omien ajatusten ja toisaalta merkittäviksi koettujen läheisten ajatusten välillä. Kaikkien opettajien ohjaustyön näkökulmasta parhaiten hyvää urapohdintatulosta, jatkokoulutukseen sitoutumista ja päätöksentekovarmuutta ennustivat oppilaan hyvät kokemukset yhteistoiminnasta, hänen myönteinen suhtautumisensa koulunkäyntiin ja opintosuoritukset. Myös itseohjautuvuus oli tilastollisesti merkitsevässä yhteydessä urapohdintaan. Itseohjautuvuus-summamuuttuja mittasi sitä, oliko oppilas kokenut, että ohjaukselle asetetut tavoitteet saavutettiin. Opettajien tulisi kiinnittää ohjauksessaan huomiota hiljaisiin ja vähän huomiota vaativiin oppilaisiin ja tukea kaikkien oppilaiden toimintakykyä. Opinto-ohjaajan taas tulisi panostaa oppilaan itsetuntemuksen kehittämiseen ja valmiuteen toimia suunnitelmallisesti. Toisen asteen nivelvaiheohjauksen painopiste tulisi siirtää päättöluokkaa varhaisemmaksi. Tutkimustulos ei tue ajatusta, että tehostettu oppilaanohjaus kohdennettaisiin opintomenestyksen mukaan, koska heikkoja urapohtijoita oli kaikissa keskiarvosanaluokissa. Opinto-ohjaajien tulisi panostaa tieto- ja viestintätekniikan hyödyntämiseen ja tehostaa koko koulun työelämäyhteistyötä.

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Das Wort Transparenz ist aus den aktuellen, öffentlichen Debatten um Informationsfreiheit nicht mehr wegzudenken. Doch wer den Transparenzdiskurs ausschließlich auf politischer Ebene im Kontext von Whistleblowern, Wikileaks, NSA-Affäre oder Piraten-Partei verortet, verkennt, dass Transparenz, wie Han feststellt, als ein systematischer Zwang wirkt, der alle gesellschaftlichen Bereiche – also auch das Bildungswesen – erfasst und sie tiefgreifend verändert. [...] Die Hattie-Studie markiert hier einen besonderen Höhepunkt, da sie alle bisher veröffentlichten Studien an Umfang und Aufwand deutlich übertrifft und dabei den Anspruch erhebt, Lernen und Lehren sichtbar zu machen. Doch welches Recht hat der Sehende auf das Sichtbar-zu-Machende? Wer profitiert hier? Unter welchen Bedingungen kann der oder die Durch-Schaute diese Veräußerung des Selbst verweigern, d.h. seine bzw. ihre Undurchschaubarkeit geltend machen? Welche anthropologischen und gesellschaftlichen Konsequenzen folgen aus dem Anspruch, den Menschen durchschaubar zu machen? Und dürfen bzw. können wir die Preisgabe von Geheimnissen bedenkenlos fordern? Bevor diese Fragen rund um die Hattie-Studie erörtert werden, sei zum Zwecke eines tieferen Verständnisses zunächst nach der Herkunft dieses Transparenztraums und des damit verbundenen Strebens nach Durch-Sichtigkeit von Mensch und Gesellschaft gefragt. (DIPF/Orig.)

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Different types of network oscillations occur in different behavioral, cognitive, or vigilance states. The rodent hippocampus expresses prominentoscillations atfrequencies between 4 and 12Hz,which are superimposed by phase-coupledoscillations (30 –100Hz).These patterns entrain multineuronal activity over large distances and have been implicated in sensory information processing and memory formation. Here we report a new type of oscillation at near- frequencies (2– 4 Hz) in the hippocampus of urethane-anesthetized mice. The rhythm is highly coherent with nasal respiration and with rhythmic field potentials in the olfactory bulb: hence, we called it hippocampal respiration-induced oscillations. Despite the similarity in frequency range, several features distinguish this pattern from locally generatedoscillations: hippocampal respiration-induced oscillations have a unique laminar amplitude profile, are resistant to atropine, couple differentlytooscillations, and are abolished when nasal airflow is bypassed bytracheotomy. Hippocampal neurons are entrained by both the respiration-induced rhythm and concurrent oscillations, suggesting a direct interaction between endogenous activity in the hippocampus and nasal respiratory inputs. Our results demonstrate that nasal respiration strongly modulates hippocampal network activity in mice, providing a long-range synchronizing signal between olfactory and hippocampal networks.

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The biological immune system is a robust, complex, adaptive system that defends the body from foreign pathogens. It is able to categorize all cells (or molecules) within the body as self-cells or non-self cells. It does this with the help of a distributed task force that has the intelligence to take action from a local and also a global perspective using its network of chemical messengers for communication. There are two major branches of the immune system. The innate immune system is an unchanging mechanism that detects and destroys certain invading organisms, whilst the adaptive immune system responds to previously unknown foreign cells and builds a response to them that can remain in the body over a long period of time. This remarkable information processing biological system has caught the attention of computer science in recent years. A novel computational intelligence technique, inspired by immunology, has emerged, called Artificial Immune Systems. Several concepts from the immune have been extracted and applied for solution to real world science and engineering problems. In this tutorial, we briefly describe the immune system metaphors that are relevant to existing Artificial Immune Systems methods. We will then show illustrative real-world problems suitable for Artificial Immune Systems and give a step-by-step algorithm walkthrough for one such problem. A comparison of the Artificial Immune Systems to other well-known algorithms, areas for future work, tips & tricks and a list of resources will round this tutorial off. It should be noted that as Artificial Immune Systems is still a young and evolving field, there is not yet a fixed algorithm template and hence actual implementations might differ somewhat from time to time and from those examples given here.

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Antecedentes: el tema de calidad de la atención en salud hoy en día es clave, y urgente de conocer, entender y aplicar por el personal de salud y en particular para el profesional de Enfermería, para lograr la calidad en los servicios de salud es necesario el control, la evaluación objetiva y sistemática de la atención de enfermería ya que se han convertido en una prioridad dentro de la profesión, debido a que el consumidor demanda atención de calidad, existiendo un mayor compromiso con la responsabilidad directa ante él público. Objetivo: determinar la calidad de atención que presta el personal de enfermería del centro de salud “Cojitambo” y su relación con el nivel de satisfacción del usuario. Metodología: se trata de un estudio descriptivo de corte transversal que permitirá determinar la calidad de atención que presta el personal de enfermería del centro de salud “Cojitambo” y su relación con el nivel de satisfacción del usuario. Universo: para el tamaño de la muestra se considera una población infinita con una proporción de insatisfacción del 20% con un nivel de confianza del 96% y una precisión del 4%. Con estos valores el tamaño de la muestra a estudiar es de 385 pacientes. Como técnicas se utilizará la entrevista, observación directa e indirecta, como instrumento el formulario avalado por la Universidad Técnica Particular de Loja en la investigación realizada por el Dr. Carlos Arévalo previa a la obtención de la maestría en gerencias en salud para el desarrollo local, para procesar la información se utilizará los programas Excel, Word y SPSS, los datos serán analizados con estadística descriptiva y presentadas en tablas y gráficas. Uso de resultados: la presente investigación pretenderá obtener datos relacionados con la medición de la calidad de atención que brinda el personal de enfermería y el nivel de satisfacción del usuario que acude al centro de salud Cojitambo.

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Le traitement des émotions joue un rôle essentiel dans les relations interpersonnelles. Des déficits dans la reconnaissance des émotions évoquées par les expressions faciales et vocales ont été démontrés à la suite d’un traumatisme craniocérébral (TCC). Toutefois, la majorité des études n’ont pas différencié les participants selon le niveau de gravité du TCC et n’ont pas évalué certains préalables essentiels au traitement émotionnel, tels que la capacité à percevoir les caractéristiques faciales et vocales, et par le fait même, la capacité à y porter attention. Aucune étude ne s’est intéressée au traitement des émotions évoquées par les expressions musicales, alors que la musique est utilisée comme méthode d’intervention afin de répondre à des besoins de prise en charge comportementale, cognitive ou affective chez des personnes présentant des atteintes neurologiques. Ainsi, on ignore si les effets positifs de l’intervention musicale sont basés sur la préservation de la reconnaissance de certaines catégories d’émotions évoquées par les expressions musicales à la suite d’un TCC. La première étude de cette thèse a évalué la reconnaissance des émotions de base (joie, tristesse, peur) évoquées par les expressions faciales, vocales et musicales chez quarante et un adultes (10 TCC modéré-sévère, 9 TCC léger complexe, 11 TCC léger simple et 11 témoins), à partir de tâches expérimentales et de tâches perceptuelles contrôles. Les résultats suggèrent un déficit de la reconnaissance de la peur évoquée par les expressions faciales à la suite d’un TCC modéré-sévère et d’un TCC léger complexe, comparativement aux personnes avec un TCC léger simple et sans TCC. Le déficit n’est pas expliqué par un trouble perceptuel sous-jacent. Les résultats montrent de plus une préservation de la reconnaissance des émotions évoquées par les expressions vocales et musicales à la suite d’un TCC, indépendamment du niveau de gravité. Enfin, malgré une dissociation observée entre les performances aux tâches de reconnaissance des émotions évoquées par les modalités visuelle et auditive, aucune corrélation n’a été trouvée entre les expressions vocales et musicales. La deuxième étude a mesuré les ondes cérébrales précoces (N1, N170) et plus tardives (N2) de vingt-cinq adultes (10 TCC léger simple, 1 TCC léger complexe, 3 TCC modéré-sévère et 11 témoins), pendant la présentation d’expressions faciales évoquant la peur, la neutralité et la joie. Les résultats suggèrent des altérations dans le traitement attentionnel précoce à la suite d’un TCC, qui amenuisent le traitement ultérieur de la peur évoquée par les expressions faciales. En somme, les conclusions de cette thèse affinent notre compréhension du traitement des émotions évoquées par les expressions faciales, vocales et musicales à la suite d’un TCC selon le niveau de gravité. Les résultats permettent également de mieux saisir les origines des déficits du traitement des émotions évoquées par les expressions faciales à la suite d’un TCC, lesquels semblent secondaires à des altérations attentionnelles précoces. Cette thèse pourrait contribuer au développement éventuel d’interventions axées sur les émotions à la suite d’un TCC.