72 resultados para Distinction


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A broad survey of harmonic dynamics in AB(2) clusters with up to N = 3000 atoms is performed using a simple rigid ion model, with ionic radii selected to give rutile as the ground state structure for the corresponding extended crystal. The vibrational density of states is already close to its bulk counterpart for N similar to 500, with characteristic differences due to surfaces, edges and vertices. Two methods are proposed and tested to map the cluster vibrational states onto the rutile crystal phonons. The net distinction between infrared (IR) active and Raman active modes that exists for bulk rutile becomes more and more blurred as the cluster size is reduced. It is found that, in general, the higher the IR activity of the mode, the more this is affected by the system size. IR active modes are found to spread over a wide frequency range for the finite clusters. Simple models based on either a crude confinement constraint or surface pressure arguments fail to reproduce the results of the calculations. The effects of the stoichiometry and dielectric properties of the surrounding medium on the vibrational properties of the clusters are also investigated.

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Information retrieval in the age of Internet search engines has become part of ordinary discourse and everyday practice: "Google" is a verb in common usage. Thus far, more attention has been given to practical understanding of information retrieval than to a full theoretical account. In Human Information Retrieval, Julian Warner offers a comprehensive overview of information retrieval, synthesizing theories from different disciplines (information and computer science, librarianship and indexing, and information society discourse) and incorporating such disparate systems as WorldCat and Google into a single, robust theoretical framework. There is a need for such a theoretical treatment, he argues, one that reveals the structure and underlying patterns of this complex field while remaining congruent with everyday practice. Warner presents a labor theoretic approach to information retrieval, building on his previously formulated distinction between semantic and syntactic mental labor, arguing that the description and search labor of information retrieval can be understood as both semantic and syntactic in character. Warner's information science approach is rooted in the humanities and the social sciences but informed by an understanding of information technology and information theory. The chapters offer a progressive exposition of the topic, with illustrative examples to explain the concepts presented. Neither narrowly practical nor largely speculative, Human Information Retrieval meets the contemporary need for a broader treatment of information and information systems.

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Pulsed Laser Deposition (PLD) was used to make Au/(Ba0.5Sr0.5)TiO3/(La0.5Sr0.5) CoO3/MgO thin film capacitor structures. Functional properties were studied with changing BST thickness from similar to1265 nm to similar to63 nm. The dielectric constant was found to decrease, and migration of T-m (the temperature at which the dielectric constant is maximum) to lower temperatures occurred as thickness was reduced. Curie-Weiss plots of the as-obtained dielectric data, indicated that the Curie temperature was also systemmatically progressively depressed. Further, fitting to expressions previously used to describe diffuse phase transitions suggested increased diffuseness in transformation behaviour as film thickness decreased. This paper discusses the care needed in interpreting the observations given above. We make particular distinction between the apparent Curie-temperature derived from Curie-Weiss plots of as-measured data, and the inherent Curie temperature determined after correction for the interfacial capacitance. We demonstrate that while the apparent Curie temperature decreases as thickness decreases, the inherent Curie temperature is thickness independent. Thickness-invariant phase transition behaviour is confirmed from analysis of polarisation loops, and from examination of the temperature dependence of the loss-tangent. We particularly note that correction of data for interfacial capacitance does not alter the position of T-m. We must therefore conclude that the position of T-m is not related simply to phase transformation behaviour in BST thin films.

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In the popular mind, the concept of 'emigration' usually refers to people voluntarily leaving one country to go to another in search of a new and better life. It presupposes some degree of choice, although it is accepted that for many emigrants, such as those who left Ireland during the nineteenth century, there were few incentives to stay at home. Current scholarship on voluntary and forced movements of people demonstrates that the distinction between the categories of 'voluntary emigrant' and 'forced exile' is often blurred. Orm Overland's study of refugee communities in the United States highlights the fact that, although the differences between the 'emigrant' and the 'exile' may be clear in extreme cases, this is not always true, as there may be 'pressing political or economic reasons behind a decision to emigrate'. Migration scholars Jan Lucassen and Leo Lucassen also question the adequacy of conceptual models of migration based on what Lindsay Proudfoot and Dianne Hall refer to as the 'straightforward binarism between free and unfree emigration'. The questions raised by these scholars are very relevant to the study of Irish people who left their country during the second half of the nineteenth century immediately after they had been discharged from prison or from Dundrum. Their stories are discussed here against a background of substantial scholarship on emigration from Ireland and on the criminal justice system within Ireland. According to David Fitzpatrick, at least eight million men, women and children emigrated from Ireland between 1801 and 1921. This large-scale movement of people was generally characterised by the voluntary emigration of individuals who funded their own passages. However, it also included schemes of assisted emigration, funded variously by governments, landlords, the poor law authorities, earlier emigrants, and philanthropists. In addition, it included people who were transported from Ireland by means of the criminal justice system a practice that had originated in the seventeenth century. What is less well known is that after the end of transportation from Ireland to eastern Australia in 1853, to Bermuda in 1863 and to Western Australia in 1868, Irish convicts continued to be channelled towards emigration by being offered early release if they agreed to leave Ireland. These people, and especially the women among them, are the subject of this article.

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Sociological assertions of religious vitality in Euro-American societies have developed a paradigm of spirituality in which, following earlier studies of the New Age, a distinction is drawn between external authority and self-authority. Methodologically and theoretically problematic, this paradigm diverts attention from people’s social practices and interactions, especially in relation to multiple religious authorities. Drawing upon ethnographic fieldwork with an English religious network, and building upon the work of Pierre Bourdieu, this paper considers situations in which multiple authorities tend to relativize each other. Conceptualizing this in terms of nonformativeness - the lack of authorities’ abilities formatively to shape religious identity, habitus, and competition over religious capital - a new understanding of individual secularization emerges that questions assertions of vitality.

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This article reviews some recent research on the development of temporal cognition, with reference to Weist's (1989) account of the development of temporal understanding. Weist's distinction between two levels of temporal decentering is discussed, and empirical studies that may be interpreted as measuring temporal decentering are described. We argue that if temporal decentering is defined simply in terms of the coordination of the temporal locations of three events, it may fail to fully capture the properties of mature temporal understanding. Characterizing the development of mature temporal cognition may require, in addition, distinguishing between event-dependent and event-independent thought about time. Experimental evidence relevant to such a distinction is described; these findings suggest that there may be important changes between 3 and 5 years in children's ability to think about points in time independently of the events that occur at those times.

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We apply all autobiographical memory framework to the Study of regret. Focusing oil the distinction between regrets for specific and general events we argue that the temporal profile of regret, usually explained in terms of the action-inaction distinction, is predicted by models of autobiographical memory. In two studies involving Participants in their sixties we demonstrate a reminiscence bump for general, but not for specific regrets. Recent regrets were more likely to be specific than general in nature. Coding regrets as actions/inactions revealed that general regrets were significantly more likely to be due to inaction while specific regrets were as likely to be clue to action as to inaction. In Study 2 we also generalised all of these findings to a group of participants in their 40s. We re-interpret existing accounts of the temporal profile of regret within the autobiographical memory framework, and Outline the practical and theoretical advantages Of Our memory-based distinction over traditional decision-making approaches to the Study of regret. (C) 2008 Elsevier Inc. All rights reserved.

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This paper begins by giving an overview of why and in which ways social psychological research can be relevant to peace. Galtung's (1969) distinction between negative peace (the absence of direct violence) and positive peace (the absence of structural violence, or the presence of social justice) is crossed with a focus on factors that are detrimental (obstacles) to peace versus factors that are conducive to peace (catalysts), yielding a two-by-two classification of social psychological contributions to peace, Research falling into these four classes is cited in brief, with a particular focus on four exemplary topics: support for military interventions as an obstacle to negative peace; antiwar activism as a catalyst of negative peace; ideologies legitimizing social inequality as an obstacle to positive peace; and commitment to human rights as a catalyst of positive peace. Based on this conceptual framework, the remaining six articles of the special issue

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Fairies and fairy tales continue to intrigue both academic and popular audiences. This article, while exploring the diverse approaches of recent scholars in this field, also raises disciplinary questions. Should the study of folklore and of the literary fairy tale be seen as separate research areas, one the preserve of the cultural historian and folklorist, the other the remit of the literary scholar? Can we even make a clear distinction in the nineteenth century between authored, literary fairy tales and orally collected supernatural folktales? If it is reductive to assume that the fairy tale can always be classified (and potentially dismissed) as children's literature, how might recent trends in Victorian studies suggest new ways of seeing and teaching the genre? Discussing the fairy tale in the context of debates over orality and authenticity, literature and science, all of these questions will be examined below.

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A new bargaining set based on notions of both internal and external stability is developed in the context of endogenous coalition formation. It allows to make an explicit distinction between within-group and outside-group deviation options. This type of distinction is not present in current bargaining sets. For the class of monotonic proper simple games, the outcomes in the bargaining set are characterized. Furthermore, it is shown that the bargaining set of any homogeneous weighted majority game contains an outcome for which the underlying coalition structure consists of a minimal winning coalition and its complement.

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Changes to software requirements occur during initial development and subsequent to delivery, posing a risk to cost and quality while at the same time providing an opportunity to add value. Provision of a generic change source taxonomy will support requirements change risk visibility, and also facilitate richer recording of both pre- and post-delivery change data. In this paper we present a collaborative study to investigate and classify sources of requirements change, drawing comparison between those pertaining to software development and maintenance. We begin by combining evolution, maintenance and software lifecycle research to derive a definition of software maintenance, which provides the foundation for empirical context and comparison. Previously published change ‘causes’ pertaining to development are elicited from the literature, consolidated using expert knowledge and classified using card sorting. A second study incorporating causes of requirements change during software maintenance results in a taxonomy which accounts for the entire evolutionary progress of applications software. We conclude that the distinction between the terms maintenance and development is imprecise, and that changes to requirements in both scenarios arise due to a combination of factors contributing to requirements uncertainty and events that trigger change. The change trigger taxonomy constructs were initially validated using a small set of requirements change data, and deemed sufficient and practical as a means to collect common requirements change statistics across multiple projects.

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Decision-making requires the perception of relevant information variables that emerge from the player–environment interaction. The purpose of the present article is to empirically assess whether players’ decisional behavior about which type of pass to make is influenced by the spatio-temporal variable tau. Time series positional data of rugby players were analyzed from video footage taken in real match scenarios. The tau of the distance motion gap between attacker and defender was calculated, along with the duration of the next pass. Results revealed that the initial tau value predicted 64% of the variance found in pass duration. A qualitative distinction of tau dynamics between two periods of the approach between the attacker and the defender was also observed. We argue that the time-to-contact between the attacker and the defender may yield information about future pass possibilities. Additionally, the informational fields constraining attacker–defender interaction may be viewed as a convergent channeling of possibilities towards a single pass solution.

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Research has shown that people often do not claim labels associated with mental retardation or learning difficulties. We discussed the interpretation that this rejection is an example of a denial process, the purpose of which is to protect self-esteem. Alternative explanations for this lack of identification were offered, based on an understanding of the socially constructed nature of diagnostic labels and on the distinction between diagnostic labels and social categories. Some of the problems in using the label as a descriptive or explanatory resource are illustrated using quotes from a study in which people who have been labeled discussed the label.

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A survey of UK chartered counselling psychologists (N = 192) was carried out to investigate how they viewed their personal therapy. Eighty-four respondents completed questionnaires about their reasons and motivations for therapy, as well as its outcome and process. The results indicated that the majority (88%) were in favour of personal therapy as a training requirement. Most respondents rated the outcome and process of their personal therapy as positive, however 27% also reported some negative effects. A factor analysis of various components of personal therapy indicated that counselling psychologists made a distinction between three factors, i.e. learning about therapy itself, issues arising out of training and dealing with personal issues. Analyses of the data suggested that aims and motivation for therapy were related to dealing with personal issues, whereas these were not important for the other factors. Learning about therapy itself was related to the number of sessions: more specifically, chose who had more than the mandatory 40 sessions rated contributions of their personal therapy co understanding therapeutic relationships and processes more highly than those who had less. Initial sessions may be used by trainees to explore personal issues, leading to a preoccupation with the self, and learning about therapy per se may only occur once this has been dealt with.

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This article discusses the rule that criminal liability does not normally attach for the causing of emotional harm or mental distress in the absence of proof of a 'recognised psychiatric injury'. It considers what is involved in the diagnosis of psychiatric injury, and to what extent the difference between such injury and 'ordinary' mental distress is one of degree rather than one of kind. It reviews the situations in which the law already criminalises the infliction of emotional harm without proof of psychiatric injury, and assesses the policy arguments for drawing the distinction in the normal case. The article concludes that the law can and should adopt a more flexible approach to cases of this sort.