917 resultados para Top-down Control


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This thesis applies a hierarchical latent trait model system to a large quantity of data. The motivation for it was lack of viable approaches to analyse High Throughput Screening datasets which maybe include thousands of data points with high dimensions. High Throughput Screening (HTS) is an important tool in the pharmaceutical industry for discovering leads which can be optimised and further developed into candidate drugs. Since the development of new robotic technologies, the ability to test the activities of compounds has considerably increased in recent years. Traditional methods, looking at tables and graphical plots for analysing relationships between measured activities and the structure of compounds, have not been feasible when facing a large HTS dataset. Instead, data visualisation provides a method for analysing such large datasets, especially with high dimensions. So far, a few visualisation techniques for drug design have been developed, but most of them just cope with several properties of compounds at one time. We believe that a latent variable model (LTM) with a non-linear mapping from the latent space to the data space is a preferred choice for visualising a complex high-dimensional data set. As a type of latent variable model, the latent trait model can deal with either continuous data or discrete data, which makes it particularly useful in this domain. In addition, with the aid of differential geometry, we can imagine the distribution of data from magnification factor and curvature plots. Rather than obtaining the useful information just from a single plot, a hierarchical LTM arranges a set of LTMs and their corresponding plots in a tree structure. We model the whole data set with a LTM at the top level, which is broken down into clusters at deeper levels of t.he hierarchy. In this manner, the refined visualisation plots can be displayed in deeper levels and sub-clusters may be found. Hierarchy of LTMs is trained using expectation-maximisation (EM) algorithm to maximise its likelihood with respect to the data sample. Training proceeds interactively in a recursive fashion (top-down). The user subjectively identifies interesting regions on the visualisation plot that they would like to model in a greater detail. At each stage of hierarchical LTM construction, the EM algorithm alternates between the E- and M-step. Another problem that can occur when visualising a large data set is that there may be significant overlaps of data clusters. It is very difficult for the user to judge where centres of regions of interest should be put. We address this problem by employing the minimum message length technique, which can help the user to decide the optimal structure of the model. In this thesis we also demonstrate the applicability of the hierarchy of latent trait models in the field of document data mining.

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The present thesis is located within the framework of descriptive translation studies and critical discourse analysis. Modern translation studies have increasingly taken into account the complexities of power relations and ideological management involved in the production of translations. Paradoxically, persuasive political discourse has not been much touched upon, except for studies following functional (e.g. Schäffner 2002) or systemic-linguistic approaches (e.g. Calzada Pérez 2001). By taking 11 English translations of Hitler’s Mein Kampf as prime examples, the thesis aims to contribute to a better understanding of the translation of politically sensitive texts. Actors involved in political discourse are usually more concerned with the emotional appeal of their message than they are with its factual content. When such political discourse becomes the locus of translation, it may equally be crafted rhetorically, being used as a tool to persuade. It is thus the purpose of the thesis to describe subtle ‘persuasion strategies’ in institutionally translated political discourse. The subject of the analysis is an illustrative corpus of four full-text translations, two abridgements, and five extract translations of Mein Kampf. Methodologically, the thesis pursues a top-down approach. It begins by delineating sociocultural and situative-agentive conditions as causal factors impinging on the individual translations. Such interactive and interpersonal factors determined textual choices. The overall textual analysis consists of an interrelated corpus-driven and corpus-based approach. It demonstrates how corpus software can be fruitfully harnessed to discern ‘ideological significations’ in the translated texts. Altogether, the thesis investigates how translational decision-makers attempted to position the source text author and his narrative in line with overall rhetorical purposes.

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We report two functional magnetic resonance imaging (fMRI) experiments which reveal a cortical network activated when perceiving coloured grids, and experiencing the McCollough effect (ME). Our results show that perception of red-black and green-black grids activate the right fusiform gyrus (area V4) plus the left and right lingual gyri, right striate cortex (V1) and left insula. The ME activated the left anterior fusiform gyrus as well as the ventrolateral prefrontal cortex, and in common with colour perception, the left insula. These data confirm the critical role of the fusiform gyrus in actual and illusory colour perception as well as revealing localized frontal cortical activation associated with the ME, which would suggest that a 'top-down' mechanism is implicated in this illusion.

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We address the important bioinformatics problem of predicting protein function from a protein's primary sequence. We consider the functional classification of G-Protein-Coupled Receptors (GPCRs), whose functions are specified in a class hierarchy. We tackle this task using a novel top-down hierarchical classification system where, for each node in the class hierarchy, the predictor attributes to be used in that node and the classifier to be applied to the selected attributes are chosen in a data-driven manner. Compared with a previous hierarchical classification system selecting classifiers only, our new system significantly reduced processing time without significantly sacrificing predictive accuracy.

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This paper outlines, using evidence from several case studies, the use of alternative forms of manufacturing strategy processes. Our investigation shows that the manufacturing strategy development practices of manufacturers are evolving in many directions; we found several alternatives to the formal top-down planning process. Manufacturers use one or more of the following alternatives with or without the top-down manufacturing strategy process: a coherent pattern of actions; manufacturing/process improvement programs; or the pursuit of core manufacturing capabilities. It appears that the various manufacturing strategy development processes may be tied to the strategic role of manufacturing in a company. This paper offers a framework that captures the relationship between the strategic role of manufacturing and the process of manufacturing strategy development. An in-depth case from a UK company illustrates the evolving forms of manufacturing strategy development processes.

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Studying the case of a young French rapper called Kamini, the authors show how the viral diffusion of a new creative product, such as a song, radically changes traditional meaning-making processes. Instead of the top-down approach in which product positioning is carefully constructed and transferred to consumers, marketers are faced with a bottom-up trend in which consumers increasingly participate in blogs and online forums to talk about products (thus, creating and diffusing meaning) before any marketing action is undertaken. Our study aims to understand the interactions and tensions between market forces that result from this pro-active role of the consumer.

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Sales leadership research has typically taken a leader-focused approach, investigating key questions from a top-down perspective. Yet considerable research outside sales has advocated a view of leadership that takes into account the fact that employees look beyond a single designated individual for leadership. In particular, the social networks of leaders have been a popular topic of investigation in the management literature, although coverage in the sales literature remains rare. The present paper conceptualizes the sales leadership role as one in which the leader must manage a network of simultaneous relationships; several types of sales manager relationships, such as the sales-manager-to-top-manager and the sales-manager-to-sales manager relationships, have received limited attention in the sales literature to date. Taking an approach based on social network theory, we develop a conceptualization of the sales manager as a "network engineer," who must manage multiple relationships, and the flows between them. Drawing from this model, we propose a detailed agenda for future sales research. © 2012 PSE National Educational Foundation. All rights reserved.

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There is a disconnection between the top-down, elite, nature of sports mega-events and the ostensible redistributive and participatory sustainable development agendas staked out by BINGOs (Business-based International Non-Governmental Organizations) such as the contemporary International Olympic Committee (IOC). Focusing specifically on the London 2012 Summer Olympic and Paralympic Games, we argue that, for all the environmental technology advances offered by sports mega-events, their dominant model remains one of a hollowed-out form of sustainable development. Despite significant technical and methodological innovations in environmental stewardship, the development model of the London Olympics remains predicated on the satisfaction of transnational investment flows. We discuss what this means for claims about the staging of a ‘green’ Olympic Games.

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Purpose of review: It has recently been argued that the future of intensive care medicine will rely on high quality management and teamwork. Therefore, this review takes an organizational psychology perspective to examine the most recent research on the relationship between teamwork, care processes, and patient outcomes in intensive care. Recent findings: Interdisciplinary communication within a team is crucial for the development of negotiated shared treatment goals and short-team patient outcomes. Interventions for maximizing team communication have received substantial interest in recent literature. Intensive care coordination is not a linear process, and intensive care teams often fail to discuss how to implement goals, trigger and align activities, or reflect on their performance. Despite a move toward interdisciplinary team working, clinical decision-making is still problematic and continues to be perceived as a top-down and authoritative process. The topic of team leadership in intensive care is underexplored and requires further research. Summary: Based on findings from the most recent research evidence in medicine and management, four principles are identified for improving the effectiveness of team working in intensive care: engender professional efficacy, create stable teams and leaders, develop trust and participative safety, and enable frequent team reflexivity.

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MOTIVATION: G protein-coupled receptors (GPCRs) play an important role in many physiological systems by transducing an extracellular signal into an intracellular response. Over 50% of all marketed drugs are targeted towards a GPCR. There is considerable interest in developing an algorithm that could effectively predict the function of a GPCR from its primary sequence. Such an algorithm is useful not only in identifying novel GPCR sequences but in characterizing the interrelationships between known GPCRs. RESULTS: An alignment-free approach to GPCR classification has been developed using techniques drawn from data mining and proteochemometrics. A dataset of over 8000 sequences was constructed to train the algorithm. This represents one of the largest GPCR datasets currently available. A predictive algorithm was developed based upon the simplest reasonable numerical representation of the protein's physicochemical properties. A selective top-down approach was developed, which used a hierarchical classifier to assign sequences to subdivisions within the GPCR hierarchy. The predictive performance of the algorithm was assessed against several standard data mining classifiers and further validated against Support Vector Machine-based GPCR prediction servers. The selective top-down approach achieves significantly higher accuracy than standard data mining methods in almost all cases.

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Much of the research on visual hallucinations (VHs) has been conducted in the context of eye disease and neurodegenerative conditions, but little is known about these phenomena in psychiatric and nonclinical populations. The purpose of this article is to bring together current knowledge regarding VHs in the psychosis phenotype and contrast this data with the literature drawn from neurodegenerative disorders and eye disease. The evidence challenges the traditional views that VHs are atypical or uncommon in psychosis. The weighted mean for VHs is 27% in schizophrenia, 15% in affective psychosis, and 7.3% in the general community. VHs are linked to a more severe psychopathological profile and less favorable outcome in psychosis and neurodegenerative conditions. VHs typically co-occur with auditory hallucinations, suggesting a common etiological cause. VHs in psychosis are also remarkably complex, negative in content, and are interpreted to have personal relevance. The cognitive mechanisms of VHs in psychosis have rarely been investigated, but existing studies point to source-monitoring deficits and distortions in top-down mechanisms, although evidence for visual processing deficits, which feature strongly in the organic literature, is lacking. Brain imaging studies point to the activation of visual cortex during hallucinations on a background of structural and connectivity changes within wider brain networks. The relationship between VHs in psychosis, eye disease, and neurodegeneration remains unclear, although the pattern of similarities and differences described in this review suggests that comparative studies may have potentially important clinical and theoretical implications. © 2014 The Author.

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The present thesis examines Palestinian-Israeli peace initiatives as politically negotiated texts and their different Arabic, English and Hebrew language versions. Its aim is to make a contribution to a deeper understanding of the role of translation and recontextualization of politically negotiated texts in situations of ongoing contemporary conflict. In modern Translation Studies, although research exists on the translation of political texts following functional (e.g. Schäffner 2002) or systemic-linguistic (e.g. Calzada-Pérez 2001) approaches or applying narrative theory (Baker 2006), peace initiatives and politically negotiated texts are still a largely under-researched genre of political texts. The thesis – which takes 31 Arabic, English and Hebrew language versions of 5 different Palestinian-Israeli peace initiatives as its corpus – operates within the framework of product-oriented Descriptive Translation Studies (Lambert and Van Gorp 1985) and Critical Discourse Analysis (Fairclough 1992). For all of the peace initiatives analysed, there exist several language versions which were made available in different contexts by different institutions and for different readerships and purposes. The thesis pursues a top-down approach. It begins with presenting the socio-cultural and political contexts of the production of the original versions of the respective peace initiatives (the source texts) and their different language versions (target texts), focusing on their underlying functions and principles of audience design. It then moves to examine how the textual profiles of the language versions of peace initiatives reflect aspects of ideology, political affiliation and power relations at both the macro- and micro-structural levels. The final step is to account for these aspects in terms of socio-political and institutional conditions of the production of the translations. The overall textual analysis demonstrates that when translated, peace initiatives can be interpreted differently by different institutions in their attempt to promote their respective political interests and narratives. Also, it is very frequently that translations produced in one specific institutional context are recontextualised for use in another one. Such recontextualisation goes hand in hand with further textual amendments. To summarize, the thesis demonstrates how these translations – as products – are (re)framed and (re)contextualized in different institutional settings in order to serve different purposes. These texts, thus, play different roles in situations of ongoing contemporary conflict depending on the institutional context in which they are presented and the purposes they set to serve. These main findings make an original contribution to the discipline of Translation Studies in respect of emphasizing the need to study translations in their socio-political, historical and institutional contexts.

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This paper investigates three case studies with regards their outsourcing initiatives from an Irish perspective, the benefits and problems they encountered, the contracts they have constructed, and where they have outsourced and the reasons behind them. The research took place over a period of two years, and the information for the case studies was gleaned from a number of sources including: published papers about the companies, the company websites, annual financial reports, the questionnaire they filled out, and interviews with key decision making personnel in the company. Follow up interviews were conducted where it was felt they were required. Key findings were that: it is very important to have the outsourcing initiative driven from the top down, and it is imperative to construct a contract that promotes a relationship based on mutual trust and respect, the use of Ireland for outsourcing, and the benefits and problem companies have experienced.

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Failure to detect patients at risk of attempting suicide can result in tragic consequences. Identifying risks earlier and more accurately helps prevent serious incidents occurring and is the objective of the GRiST clinical decision support system (CDSS). One of the problems it faces is high variability in the type and quantity of data submitted for patients, who are assessed in multiple contexts along the care pathway. Although GRiST identifies up to 138 patient cues to collect, only about half of them are relevant for any one patient and their roles may not be for risk evaluation but more for risk management. This paper explores the data collection behaviour of clinicians using GRiST to see whether it can elucidate which variables are important for risk evaluations and when. The GRiST CDSS is based on a cognitive model of human expertise manifested by a sophisticated hierarchical knowledge structure or tree. This structure is used by the GRiST interface to provide top-down controlled access to the patient data. Our research explores relationships between the answers given to these higher-level 'branch' questions to see whether they can help direct assessors to the most important data, depending on the patient profile and assessment context. The outcome is a model for dynamic data collection driven by the knowledge hierarchy. It has potential for improving other clinical decision support systems operating in domains with high dimensional data that are only partially collected and in a variety of combinations.

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The human and material cost of type 2 diabetes is a cause of increasing concern for health professionals, representative organisations and governments worldwide. The scale of morbidity and mortality has led the United Nations to issue a resolution on diabetes, calling for national policies for prevention, treatment and care. There is clearly an urgent need for a concerted response from all interested parties at the community, national and international level to work towards the goals of the resolution and create effective, sustainable treatment models, care systems and prevention strategies. Action requires both a 'bottom-up' approach of public awareness campaigns and pressure from healthcare professionals, coupled with a 'top-down' drive for change, via partnerships with governments, third sector (non-governmental) organisations and other institutions. In this review, we examine how existing collaborative initiatives serve as examples for those seeking to implement change in health policy and practice in the quest to alleviate the health and economic burden of diabetes. Efforts are underway to provide continuous and comprehensive care models for those who already have type 2 diabetes; in some cases, national plans extend to prevention strategies in attempts to improve overall public health. In the spirit of partnership, collaborations with governments that incorporate sustainability, long-term goals and a holistic approach continue to be a driving force for change. It is now critical to maintain this momentum and use the growing body of compelling evidence to educate, inform and deliver a long-term, lasting impact on patient and public health worldwide. © 2007 The Authors.