873 resultados para Support Vector Machines and Naive Bayes Classifier
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Previous research points to the importance of both kin and non-kin ties within social networks as sources of social support. This study examines the kin and non-kin providers of specific types of support to dual-parent low-income Australian families caring for young children. The study highlights the importance of family and friends as support providers. Study Participants tended to rely on family, including parents, siblings and other family members, and friends for emotional and information support. Parents also tended to provide material and practical support. While neighbors and community agencies offered some emotional and information support, overall, these sources were minimal. (C) 2002 Wiley Periodicals, Inc.
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Fiji disease (FD) of sugar cane caused by Fiji disease virus (FDV) is transmitted by the planthopper Perkinsiella saccharicida Kirkaldy (Hemiptera: Delphacidae). FD is effectively managed by using resistant cultivars, but whether the resistance is for the vector or for the Virus is Unknown. This knowledge would help develop a rapid and reliable glasshouse-based screening method for disease resistance. Sugar cane cultivars resistant, intermediate, and susceptible to FD were screened in a glasshouse, and the relationship between vector preferences and FD incidence was studied. Cultivar preference by nymphs increased with an increase in cultivar susceptibility to FD, but the relationship between adult preference and FD resistance was not significant. There was a positive correlation between the vector population and FD incidence, and the latent period for symptom expression declined with the increase in the vector populations. FD incidence in the glasshouse trial reflected the field-resistance status of sugar cane cultivars with known FD-resistance scores. The results suggest that resistance to FD in sugar cane is mediated by cultivar preference of the plant-hopper vector.
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In 2002, an integrated basic science course was introduced into the Bachelor of Dental Sciences programme at the University of Queensland, Australia. Learning activities for the Metabolism and Nutrition unit within this integrated course included lectures, problem-based learning tutorials, computer-based self-directed learning exercises and practicals. To support student learning and assist students to develop the skills necessary to become lifelong learners, an extensive bank of formative assessment questions was set up using the commercially available package, WebCT®. Questions included short-answer, multiple-choice and extended matching questions. As significant staff time was involved in setting up the question database, the extent to which students used the formative assessment and their perceptions of its usefulness to their learning were evaluated to determine whether formative assessment should be extended to other units within the course. More than 90% of the class completed formative assessment tasks associated with learning activities scheduled in the first two weeks of the block, but this declined to less than 50% by the fourth and final week of the block. Patterns of usage of the formative assessment were also compared in students who scored in the top 10% for all assessment for the semester with those who scored in the lowest 10%. High-performing students accessed the Web-based formative assessment about twice as often as those who scored in the lowest band. However, marks for the formative assessment tests did not differ significantly between the two groups. In a questionnaire that was administered at the completion of the block, students rated the formative assessment highly, with 80% regarding it as being helpful for their learning. In conclusion, although substantial staff time was required to set up the question database, this appeared to be justified by the positive responses of the students.
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The HCI community is actively seeking novel methodologies to gain insight into the user’s experience during interaction with both the application and the content. We propose an emotional recognition engine capable of automatically recognizing a set of human emotional states using psychophysiological measures of the autonomous nervous system, including galvanic skin response, respiration, and heart rate. A novel pattern recognition system, based on discriminant analysis and support vector machine classifiers is trained using movies’ scenes selected to induce emotions ranging from the positive to the negative valence dimension, including happiness, anger, disgust, sadness, and fear. In this paper we introduce an emotion recognition system and evaluate its accuracy by presenting the results of an experiment conducted with three physiologic sensors.
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The real Cloud and Ubiquitous Manufacturing systems require effectiveness and permanent availability of resources, their capacity and scalability. One of the most important problems for applications management over cloud based platforms, which are expected to support efficient scalability and resources coordination following SaaS implementation model, is their interoperability. Even application dashboards need to easily incorporate those new applications, their interoperability still remains a big problem to override. So, the possibility to expand these dashboards with efficiently integrated communicational cloud based services (cloudlets) represents a relevant added value as well as contributes to solving the interoperability problem. Following the architecture for integration of enriched existing cloud services, as instances of manufacturing resources, this paper: a) proposes a cloud based web platform to support dashboard integrating communicational services, and b) describe an experimentation to sustain the theory that the effective and efficient interoperability, especially in dynamic environments, could be achieved only with human intervention.
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Ao longo dos tempos tem existido um avanço, nas empresas, dirigido à preocupação com o bemestar dos trabalhadores, adotando por isso medidas preventivas. A formação especializada em Medicina do Trabalho é indispensável para o exercício de atividades de prevenção dos riscos profissionais e de promoção da saúde. A postura corporal pode ser definida como a posição e a orientação global do corpo e membros relativamente uns aos outros. Qualquer desvio na forma da coluna vertebral pode gerar solicitações funcionais prejudiciais que ocasionam um aumento de fadiga no trabalhador e leva ao longo do tempo a lesões graves. Cada vez mais surgem doenças profissionais provocadas pela adoção de más posturas, na realização de tarefas diárias dos trabalhadores. A boa postura corporal é uma tarefa específica que representa uma interação complexa entre a função biomecânica e neuromuscular. No presente plano de dissertação foram estudados diferentes classificadores tendo como objetivo classificar boas e más posturas corporais de trabalhadores em contexto de trabalho. Assim foram estudados diferentes classificadores de machine learnig, redes neuronais artificiais, support vector machine, árvores de decisão, análise discriminante, regressão logística, treebagger e naíve bayes. Para treino de classificadores foi realizada a aquisição tridimensional da postura da espinha a 100 pessoas, passando por uma parametrização e treino de diferentes classificadores para a determinação automática do tipo de postura corporal. O classificador que obteve melhor desempenho foi o Treebagger com uma classificação para True Positive de 93,3% e True Negative de 96,2%.
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Previous studies (1982,1987) have emphasized the superiority of sylvatic vector species over domestic species as xenodiagnostic agents in testing hosts with acute or chronic infections by T. cruzi "Y" stock. The present study, which is unique in that it contains data on both infectivity rates produced by the same stock in 11 different vector species and also the reaction of the same vector species to seven different parasite stocks, establishes the general validity of linking efficiency of xenodiagnosis to the biotope of its agent. For example, infectivity rates produced by "São Felipe" stock varied from 82.5% to 98.3% in sylvatic vectors but decreased to 42.5% to 71.3% in domestic species. "Colombiana" stock produced in the same sylvatic vectors infectivity rates ranging from 12.5% to 45%. These shrank to 5%-22.5% in domestic bugs. The functional role of the biotope in the vector-parasite interaction has not been eluddated. But since this phenomenon has been observed to be stable and easy to reproduce, it leads us to believe that the results obtained are valid. Data presented also provide increasing evidence that the infectivity rates exhibited by bugs from xenodiagnosis in chronic hosts, are parasite stock specific. For example, infectivity rates produced by "Berenice", "Y", "FL" and "CL" varied in R. neglectus from 26.3% to 75%; in P. megistus from 56.3% to 83.8%; in T. sordida from 28.8% to 58.8% in T. pseudomaculata from 41.3% to 66.3% and in T. rubrovaria from 48.8% to 85%. Data from xenodiagnosis in the same hosts, carrying acute infections by the same parasite stocks, gave the five sylvatic vectors a positive rating of approximately 100%, thus suggesting that the heavy loads of parasites circulating in the acute hosts obscured the characteristic interspecific differences for the parasite stock. Nonetheless these latter were revealed in the same hosts with chronic infections stimulated by very low numbers of the same parasite stocks. Certain observations here described lead us to speculate as to the possibility of further results from other parasite stocks, allowing the association of the infectivity rates produced in bugs by different parasite stocks with the isoenzymic patterns revealed by these stocks.
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In recent years, Power Systems (PS) have experimented many changes in their operation. The introduction of new players managing Distributed Generation (DG) units, and the existence of new Demand Response (DR) programs make the control of the system a more complex problem and allow a more flexible management. An intelligent resource management in the context of smart grids is of huge important so that smart grids functions are assured. This paper proposes a new methodology to support system operators and/or Virtual Power Players (VPPs) to determine effective and efficient DR programs that can be put into practice. This method is based on the use of data mining techniques applied to a database which is obtained for a large set of operation scenarios. The paper includes a case study based on 27,000 scenarios considering a diversity of distributed resources in a 32 bus distribution network.
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Liver steatosis is a common disease usually associated with social and genetic factors. Early detection and quantification is important since it can evolve to cirrhosis. In this paper, a new computer-aided diagnosis (CAD) system for steatosis classification, in a local and global basis, is presented. Bayes factor is computed from objective ultrasound textural features extracted from the liver parenchyma. The goal is to develop a CAD screening tool, to help in the steatosis detection. Results showed an accuracy of 93.33%, with a sensitivity of 94.59% and specificity of 92.11%, using the Bayes classifier. The proposed CAD system is a suitable graphical display for steatosis classification.
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Dissertação para obtenção do grau de Mestre em Engenharia Informática
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Liver steatosis is mainly a textural abnormality of the hepatic parenchyma due to fat accumulation on the hepatic vesicles. Today, the assessment is subjectively performed by visual inspection. Here a classifier based on features extracted from ultrasound (US) images is described for the automatic diagnostic of this phatology. The proposed algorithm estimates the original ultrasound radio-frequency (RF) envelope signal from which the noiseless anatomic information and the textural information encoded in the speckle noise is extracted. The features characterizing the textural information are the coefficients of the first order autoregressive model that describes the speckle field. A binary Bayesian classifier was implemented and the Bayes factor was calculated. The classification has revealed an overall accuracy of 100%. The Bayes factor could be helpful in the graphical display of the quantitative results for diagnosis purposes.
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Modern factories are complex systems where advances in networking and information technologies are opening new ways towards higher efficiency. Such move is being driven by market rules with ever-increasing competition levels, in search for faster time-to-market, improved process yield, non-stop operations, flexible manufacturing and tighter supply-chain coupling. All these aims present a common requirement, i.e. a realtime flow of information, from the plant-floor up to the management, maintenance, suppliers and clients, to support accurate monitoring and control of the factory. This stresses the importance achieved by the communication infrastructure in modern manufacturing industry. This paper presents the authors view concerning the current trends in modern factory communication systems. It addresses the problems of seamlessly integrating different information flows with diverse requirements, mainly in terms of timeliness. In this aspect, the debate between event-triggered and time-triggered communication is revisited as well as the joint support for both types of traffic. Finally, a view of where factory communication systems are moving to is also presented, showing the impact of open and widely available technologies.
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In the past few years Tabling has emerged as a powerful logic programming model. The integration of concurrent features into the implementation of Tabling systems is demanded by need to use recently developed tabling applications within distributed systems, where a process has to respond concurrently to several requests. The support for sharing of tables among the concurrent threads of a Tabling process is a desirable feature, to allow one of Tabling’s virtues, the re-use of computations by other threads and to allow efficient usage of available memory. However, the incremental completion of tables which are evaluated concurrently is not a trivial problem. In this dissertation we describe the integration of concurrency mechanisms, by the way of multi-threading, in a state of the art Tabling and Prolog system, XSB. We begin by reviewing the main concepts for a formal description of tabled computations, called SLG resolution and for the implementation of Tabling under the SLG-WAM, the abstract machine supported by XSB. We describe the different scheduling strategies provided by XSB and introduce some new properties of local scheduling, a scheduling strategy for SLG resolution. We proceed to describe our implementation work by describing the process of integrating multi-threading in a Prolog system supporting Tabling, without addressing the problem of shared tables. We describe the trade-offs and implementation decisions involved. We then describe an optimistic algorithm for the concurrent sharing of completed tables, Shared Completed Tables, which allows the sharing of tables without incurring in deadlocks, under local scheduling. This method relies on the execution properties of local scheduling and includes full support for negation. We provide a theoretical framework and discuss the implementation’s correctness and complexity. After that, we describe amethod for the sharing of tables among threads that allows parallelism in the computation of inter-dependent subgoals, which we name Concurrent Completion. We informally argue for the correctness of Concurrent Completion. We give detailed performance measurements of the multi-threaded XSB systems over a variety of machines and operating systems, for both the Shared Completed Tables and the Concurrent Completion implementations. We focus our measurements inthe overhead over the sequential engine and the scalability of the system. We finish with a comparison of XSB with other multi-threaded Prolog systems and we compare our approach to concurrent tabling with parallel and distributed methods for the evaluation of tabling. Finally, we identify future research directions.
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Simulators are indispensable tools to support the development and testing of cooperating objects such as wireless sensor networks (WSN). However, it is often not possible to compare the results of different simulation tools. Thus, the goal of this paper is the specification of a generic simulation platform for cooperating objects. We propose a platform that consists of a set of simulators that together fulfill desired simulator properties. We show that to achieve comparable results the use of a common specification language for the software-under-test is not feasible. Instead, we argue that using common input formats for the simulated environment and common output formats for the results is useful. This again motivates that a simulation tool consisting of a set of existing simulators that are able to use common scenario-input and can produce common output which will bring us a step closer to the vision of achieving comparable simulation results.
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Portugal had only very few foresight exercises on the automobile sector, and the most recent one was a survey held in a project on work organisation systems in the automobile industry, its recent historical paths and the special strategies of location of companies (the WorTiS project). This involved several teams with different disciplinary backgrounds and from two Portuguese universities. The provisional main results of the first round of a Delphi survey held in Portugal on the automotive sector were already published, but a further analysis was not yet done. This foresight survey was done under the WorTiS project, developed in 2004 by IET – Research Centre on Enterprise and Work Innovation (at FCT-UNL), and financed by the Portuguese Ministry of Science and Technology. Some of this experience on foresight analysis is also been transferred to other projects, namely the WORKS project on work organisation restructuring in the knowledge society that received the support from EC and still is running. The majority of experts considered having an average of less knowledge in almost all the scenario topics presented. This means that information on the automotive industry is not spread enough among academics or experts in related fields (regional scientists, innovation economists, engineers, sociologists). Some have a good knowledge but in very specialised fields. Others have expertise on foresight, or macroeconomics, or management sciences, but feel insecure on issues related with futures of automobile sector. Nevertheless, we considered specially the topics where the experts considered themselves to have some knowledge. There were no “irrelevant” topics considered as such by the expert panel. There are also no topics that are not considered a need for co-operation. The lack of technological infrastructures was not considered as a hindered factor for the accomplishment of any scenario. The experts’ panel considered no other international competence besides US, Japan or Germany in these topics. Special focus will be made in this paper on the topic 2. Public policy and automobile industries, and more specifically on the technological and/or research policies issues, where one can specify the automobile’s role in transport policies with further implications like environment, safety, energy, mobility.