992 resultados para platform studies


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In a 2-yr multiple-site field study conducted in western Nebraska during 1999 and 2000, optimum dryland corn (Zea mays L.) population varied from less than 1.7 to more than 5.6 plants m(-2), depending largely on available water resources. The objective of this study was to use a modeling approach to investigate corn population recommendations for a wide range of seasonal variation. A corn growth simulation model (APSIM-maize) was coupled to long-term sequences of historical climatic data from western Nebraska to provide probabilistic estimates of dryland yield for a range of corn populations. Simulated populations ranged from 2 to 5 plants m(-2). Simulations began with one of three levels of available soil water at planting, either 80, 160, or 240 mm in the surface 1.5 m of a loam soil. Gross margins were maximized at 3 plants m(-2) when starting available water was 160 or 240 mm, and the expected probability of a financial loss at this population was reduced from about 10% at 160 mm to 0% at 240 mm. When starting available water was 80 mm, average gross margins were less than $15 ha(-1), and risk of financial loss exceeded 40%. Median yields were greatest when starting available soil water was 240 mm. However, perhaps the greater benefit of additional soil water at planting was reduction in the risk of making a financial loss. Dryland corn growers in western Nebraska are advised to use a population of 3 plants m(-2) as a base recommendation.

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With recent advances in molecular biology, it is now possible to use the trace amounts of DNA in faeces to non-invasively sample endangered species for genetic studies. A highly vulnerable population of approximately 100 great bustards (Otis tarda) exists in Morocco necessitating the use of non-invasive protocols to study their genetic structure. Here we report a reliable silica-based method to extract DNA from great bustard faeces. We found that successful extraction and amplification correlated strongly with faeces freshness and composition. We could not extract amplifiable DNA from 30% of our samples as they were dry or contained insect material. However 100% of our fresh faecal samples containing no obvious insect material worked, allowing us to assess the levels of genetic variation among 25 individuals using a 542 bp control region sequence. We were able to extract DNA from four out of five other avian species, demonstrating that faeces represents a suitable source of DNA for population genetics studies in a broad range of species.

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Esta dissertação apresenta o desenvolvimento de uma plataforma multimodal de aquisição e processamento de sinais. O projeto proposto insere-se no contexto do desenvolvimento de interfaces multimodais para aplicação em dispositivos robóticos cujo propósito é a reabilitação motora adaptando o controle destes dispositivos de acordo com a intenção do usuário. A interface desenvolvida adquire, sincroniza e processa sinais eletroencefalográficos (EEG), eletromiográficos (EMG) e sinais provenientes de sensores inerciais (IMUs). A aquisição dos dados é feita em experimentos realizados com sujeitos saudáveis que executam tarefas motoras de membros inferiores. O objetivo é analisar a intenção de movimento, a ativação muscular e o início efetivo dos movimentos realizados, respectivamente, através dos sinais de EEG, EMG e IMUs. Para este fim, uma análise offline foi realizada. Nessa análise, são utilizadas técnicas de processamento dos sinais biológicos e técnicas para processar sinais provenientes de sensores inerciais. A partir destes, os ângulos da articulação do joelho também são aferidos ao longo dos movimentos. Um protocolo experimental de testes foi proposto para as tarefas realizadas. Os resultados demonstraram que o sistema proposto foi capaz de adquirir, sincronizar, processar e classificar os sinais combinadamente. Análises acerca da acurácia dos classificadores utilizados mostraram que a interface foi capaz de identificar intenção de movimento em 76, 0 ± 18, 2% dos movimentos. A maior média de tempo de antecipação ao movimento foi obtida através da análise do sinal de EEG e foi de 716, 0±546, 1 milisegundos. A partir da análise apenas do sinal de EMG, este valor foi de 88, 34 ± 67, 28 milisegundos. Os resultados das etapas de processamento dos sinais biológicos, a medição dos ângulos da articulação, bem como os valores de acurácia e tempo de antecipação ao movimento se mostraram em conformidade com a literatura atual relacionada.

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This article examines the formative platform of the Congress of Panama of 1826. It seeks to support the hypothesis that the nature and scope of the first test of integration in the Western Hemisphere depended critically on the platform created by Simón Bolívar and other Latin American Independence heroes from the Declaration of Independence of Venezuela in 1810 until the last bilateral agreement of 1826. In that respect, it corroborates the Latin American Identity of the initiative.

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The relation between patient and physician in most modern Health Care Sys- tems is sparse, limited in time and very in exible. On the other hand, and in contradiction with several recent studies, most physicians do not rely their patient diagnostics evaluations on intertwined psychological and social nature factors. Facing these problems and trying to improve the patient/physician relation we present a mobile health care solution to im- prove the interaction between the physician and his patients. The solution serves not only as a privileged mean of communication between physicians and patients but also as an evolutionary intelligent platform delivering a mobile rule based system.

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The relation between patient and physician in most modern Health Care Systems is sparse, limited in time and very inflexible. On the other hand, and in contradiction with several recent studies, most physicians do not rely their patient diagnostics evaluations on intertwined psychological and social nature factors. Facing these problems and trying to improve the patient/physician relation we present a mobile health care solution to improve the interaction between the physician and his patients. The solution serves not only as a privileged mean of communication between physicians and patients but also as an evolutionary intelligent platform delivering a mobile rule based system.

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This paper proposes a wireless EEG acquisition platform based on Open Multimedia Architecture Platform (OMAP) embedded system. A high-impedance active dry electrode was tested for improving the scalp- electrode interface. It was used the sigma-delta ADS1298 analog-to-digital converter, and developed a “kernelspace” character driver to manage the communications between the converter unit and the OMAP’s ARM core. The acquired EEG signal data is processed by a “userspace” application, which accesses the driver’s memory, saves the data to a SD-card and transmits them through a wireless TCP/IP-socket to a PC. The electrodes were tested through the alpha wave replacement phenomenon. The experimental results presented the expected alpha rhythm (8-13 Hz) reactiveness to the eyes opening task. The driver spends about 725 μs to acquire and store the data samples. The application takes about 244 μs to get the data from the driver and 1.4 ms to save it in the SD-card. A WiFi throughput of 12.8Mbps was measured which results in a transmission time of 5 ms for 512 kb of data. The embedded system consumes about 200 mAh when wireless off and 400 mAh when it is on. The system exhibits a reliable performance to record EEG signals and transmit them wirelessly. Besides the microcontroller-based architectures, the proposed platform demonstrates that powerful ARM processors running embedded operating systems can be programmed with real-time constrains at the kernel level in order to control hardware, while maintaining their parallel processing abilities in high level software applications.

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The Ambient Assisted Living (AAL) area is in constant evolution, providing new technologies to users and enhancing the level of security and comfort that is ensured by house platforms. The Ambient Assisted Living for All (AAL4ALL) project aims to develop a new AAL concept, supported on a unified ecosystem and certification process that enables a heterogeneous environment. The concepts of Intelligent Environments, Ambient Intelligence, and the foundations of the Ambient Assisted Living are all presented in the framework of this project. In this work, we consider a specific platform developed in the scope of AAL4ALL, called UserAccess. The architecture of the platform and its role within the overall AAL4ALL concept, the implementation of the platform, and the available interfaces are presented. In addition, its feasibility is validated through a series of tests.

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In the 70s, a new line of research focused on the study of the influence of the audit report on the decision process of investors, financial analysts and credit analysts. Notwithstanding the numerous studies that have been carried out, results have not been consistent. Given the above, and considering the lack, in Portugal, of a research of this nature, it seems urgent to carry out a study that allows the analysis of the use of the audit report, as well as its influence on the decision making process of Portuguese stakeholders. For that purpose, in the light of the positivist research paradigm, a questionnaire was designed, which was administered by mail and on the Survey Monkey platform to a sample of institutional investors, financial analysts and credit analysts. The statistical analysis of the data obtained was undertaken with resource to the Statistical Package for the Social Sciences and SmartPLS 2.0. Corroborating the literature review and the assumptions of the Agency Theory and the Stakeholder Theory, used in the theoretical framework of analysis, empirical evidence has shown that the audit report influences the decision of institutional investors, financial analysts and credit analysts, and that the opinion expressed in that document is the most determinant factor of this influence. In addition to this factor, it was found that the degree of utilization of the audit report, as well as the value ascribed to this document, determine its influence in the decision process of research groups studied. Only in the case of institutional investors, the results did not reveal a correlation between the utility ascribed to the audit report and the influence of this document in their decision making process. In turn, the statistical inference of the model explaining the degree of use of the audit report revealed that it is conditioned by the perceived quality of the information enclosed in the audit report, the utility assigned to the audit report on the decision process, as well as the relevance of the other sources of information used by stakeholders. Therefore, this study allowed proving the importance of the audit report to its users. As a result, we believe to have filled a gap in national literature and to have contributed to the enhancement of international literature. The importance that this document has for the development of any country is, therefore, shown, and it is urgent to maintain rigor in the selection of its staff, in the development of its standards, and especially in the development of audits. Moreover, we also consider that this research may contribute to the improvement of the audit report, insofar as it will help professional bodies to understand the information needs and perceptions of stakeholders.

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This paper studies the use of results oriented performance information (outputs and outcomes) by local elected politicians (aldermen) in top managers’ performance evaluation. The main goal is to understand the top managers’ performance evaluation process conducted by Portuguese aldermen and to identify the dominant evaluation style. In line with Bogt (2001), an exploratory field research was developed in three large municipalities: Porto, Braga and Matosinhos. We intend to answer the following research questions: to what extent are local politicians (aldermen) 1 using results information (about outputs and outcomes) to evaluate top managers’ performance? Do aldermen give any importance to quantitative output information and report them on current planning and control documents? Will the output performance information be used on performance evaluation in a different way concerning policy field (task orientation)? Based on the Hopwood evaluation styles (adapted from the private to the public sector by Bogt, 2001), we have found that the performance evaluation process of top managers is more featured by the ‘operations-conscious styles’ (or ‘implicit style’). Portuguese aldermen recognize the importance to quantify outputs and outcomes, but these days they focus on the information about activities and the realized operations when they evaluate performance. We haven´t found significant differences between different tasks (some exceptions for culture and environment areas). However, the municipality of Matosinhos paid more attention on quantitative performance information. This finding is reinforced by the quality of quantitative data on outputs reported on its management report. Generally speaking, aldermen are aware that more attention should be paid to quantitative information about results and performance, taking into account recent reforms introduced in Portuguese municipalities (PLG) on this field, but the ‘implicit’ style is dominant.

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LUDA is a research project of Key Action 4 "City of Tomorrow & Cultural Heritage" of the programme "Energy, Environment and Sustainable Development" within the Fifth Framework Programme of the European Commission

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Redescription of Culex (Melanoconion) oedipus Root and of Cx. (Mel.) plectoporpe Root, as well as the description of a new one, named Cx. (Mel.) rabelloi, are made. The material was collected in S.Paulo State, Southern Brazil. The descriptions include adults, pupal and larval stages, illustrating the morphological aspects and with pictures of breeding places. Some data about known distribution and bionomics are presented, remarking that all the three species seem to be closely associated with artificial manmade enviroments.