Energy consumption on systems that have a continuous power source is tightly-related to both the computing time of an application and its required CPU load. Considering the scope of HPC applications which commonly hav...
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For water-cooled stator bar of power generator, leaks of water at the copper strand brazing location will reduce dramatically its insulation resistance. Therefore, the insulation resistance measurement is an important...
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For water-cooled stator bar of power generator, leaks of water at the copper strand brazing location will reduce dramatically its insulation resistance. Therefore, the insulation resistance measurement is an important and simple test to perform in the periodic maintenance program. The temperature has an important effect on the insulation resistance. To correctly trend the insulation resistance of the winding, a correction factor has to be applied. This paper describes experimental data performed on both dry and wet epoxy-mica insulation from bars removed from an operating generator. The results are compared with different correction models. They show an important difference of the temperature coefficient between the dry and wet bar.
The use of recommender systems is widespread in several everyday systems. People are now exposed to different offerings, based on their interests, in order to anticipate decisions. However, in a different way recommen...
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The use of recommender systems is widespread in several everyday systems. People are now exposed to different offerings, based on their interests, in order to anticipate decisions. However, in a different way recommender systems for accessibility domain require further studies and researches. In order to provide resources for people with special needs, we developed the Vulcanus, a recommender system designed for people with disabilities, offering access to resources according user's needs. The recommender system approaches concepts from ubiquitous computing, such as user profiles, context awareness, trails management, and similarity analysis. Vulcanus uses two different approaches: resources patterns and categories patterns; where different systems can use it, for example as a Web Service. Vulcanus was evaluated in different scenarios. These scenarios used more than 800 thousands of trails that simulate wheelchair users using resources along six months. The obtained results show that both approaches are able to provide relevant recommendations, providing resources that in fact can support users' needs.
Research regarding stroke indicates that short elapsed time between accident and treatment can be fundamental to allow saving patient's life and avoid future sequels. This paper describes a model for monitoring an...
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Research regarding stroke indicates that short elapsed time between accident and treatment can be fundamental to allow saving patient's life and avoid future sequels. This paper describes a model for monitoring and rescue victims in situations of possible stroke occurrence. It uses stroke symptoms that can be monitored by mobile equipment, ambient intelligence and artificial neural networks. The model is independent from human operation and applications or third parties devices, therefore adding facilities to increase the quality of life for people with stroke sequel, due to constant monitoring and follow-up provided, allowing the stroke patient to consider a recovery period with greater autonomy. A prototype based on free software platforms was developed, in order to assess the accuracy and the time elapsed between the prototype to detect and to send an alert. The results indicate a positive outlook for the work continuity.
New information and communication technologies enable a better management of the available resources in a smart city. Leaders need tools to analyze data for better decisions, anticipate problems and resolve them proac...
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The use of electronic medias for payment has been increasingly adopted, instead of employing money in currency paper or check directly. Considering this electronic funds transfer (EFT) scenario, we developed a model c...
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ISBN:
(纸本)9781450324694
The use of electronic medias for payment has been increasingly adopted, instead of employing money in currency paper or check directly. Considering this electronic funds transfer (EFT) scenario, we developed a model called GetLB which comprises not only a completely new and efficient scheduler but also a cooperative communication infrastructure for handling heterogeneous and dynamic environments. The scientific contribution consists of a scheduling heuristic that combines static data from transactions and dynamic one from processing nodes to overcome the limitations of Round-Robin. Besides the GetLB's description, this article also presents a prototype evaluation by using both traces and configurations obtained with a real EFT company. Copyright 2014 ACM.
Periods in the soybean summer cycle that are sensitive to the occurrence of high temperatures were studied. An analysis was performed on the variability of soybean yields associated with crop canopy temperatures durin...
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Periods in the soybean summer cycle that are sensitive to the occurrence of high temperatures were studied. An analysis was performed on the variability of soybean yields associated with crop canopy temperatures during key development periods. A land surface temperature (LST) data series from MODIS (Moderate Resolution Imaging Spectroradiometer) on the Aqua satellite was processed between 2003 and 2012 that covered the entire state of Rio Grande do Sul, in Brazil. Enhanced vegetation index (EVI) data from MODIS on the Terra satellite were used to monitor the LST during different phenological stages. Spatially interpolated maps of soybean yield distributions were generated using data obtained from Instituto Brasileiro de Geografia e Estatística (IBGE) at state and municipality levels. The results indicate that canopy-LST occurrence in mid-February, during the grain filling, is most correlated to yield reduction (R2 = 0.82 and RMSD = 14.4%). At the state level, the average yield is 2003 kg·ha-1 with a standard deviation of 308 kg·ha-1. The overall average of the canopy-LST is 305.0 K (31.8°C) with a standard deviation of 1.9 K. The slope of the downward linear relationship between canopy-LST and yield was -28.7%. These results indicate that monitoring heat wave events can provide important information for characterising agriculture vulnerability.
New information and communication technologies enable a better management of the available resources in a smart city. Leaders need tools to analyze data for better decisions, anticipate problems and resolve them proac...
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New information and communication technologies enable a better management of the available resources in a smart city. Leaders need tools to analyze data for better decisions, anticipate problems and resolve them proactively. In this context, this article proposes a simulation tool to analyze the interaction of typical cities occurrences like criminal and police. The information of both occurrences, including their densities, are inserted and visualized on a city map. Each record is marked on the GPS point where it happened. From these inputs data, the interactions are modeled by Voronoi Diagrams. The occurrences change their position according to the size area of the opposite event. In this way, crimes runway from police and police catch crimes occurrences. As results, we show that a large increase of police actions will not influence quantitatively in the reduction of criminal occurrences out of a critical zone.
Elasticity is one of the key features of cloud computing. It allows applications to dynamically scale computing and storage resources, avoiding over- and under-provisioning. In high performance computing (HPC), initia...
Elasticity is one of the key features of cloud computing. It allows applications to dynamically scale computing and storage resources, avoiding over- and under-provisioning. In high performance computing (HPC), initiatives are normally modeled to handle bag-of-tasks or key-value applications through a load balancer and a loosely-coupled set of virtual machine (VM) instances. In the joint-field of Message Passing Interface (MPI) and tightly-coupled HPC applications, we observe the need of rewriting source codes, previous knowledge of the application and/or stop-reconfigure-and-go approaches to address cloud elasticity. Besides, there are problems related to how profit this new feature in the HPC scope, since in MPI 2.0 applications the programmers need to handle communicators by themselves, and a sudden consolidation of a VM, together with a process, can compromise the entire execution. To address these issues, we propose a PaaS-based elasticity model, named AutoElastic. It acts as a middleware that allows iterative HPC applications to take advantage of dynamic resource provisioning of cloud infrastructures without any major modification. AutoElastic provides a new concept denoted here as asynchronous elasticity, i.e., it provides a framework to allow applications to either increase or decrease their computing resources without blocking the current execution. The feasibility of AutoElastic is demonstrated through a prototype that runs a CPU-bound numerical integration application on top of the OpenNebula middleware. The results showed the saving of about 3 min at each scaling out operations, emphasizing the contribution of the new concept on contexts where seconds are precious.
Attaining reliable and timely agricultural estimates is very important everywhere, and in Brazil, due to its characteristics, this is especially true. In this study, estimations of crop production were made based on t...
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Attaining reliable and timely agricultural estimates is very important everywhere, and in Brazil, due to its characteristics, this is especially true. In this study, estimations of crop production were made based on the temporal profiles of the Enhanced Vegetation Index (EVI) obtained from Moderate Resolution Imaging Spectroradiometer (MODIS) images. The objective was to evaluate the coupled model (CM) performance of crop area and crop yield estimates based solely on MODIS/EVI as input data in Rio Grande do Sul State, which is characterized by high variability in seasonal soybean yields, due to different crop development conditions. The resulting production estimates from CM were compared to official agricultural statistics of Brazilian Institute of Geography and Statistics (IBGE) and the National Company of Food Supply (CONAB) at different levels from 2000/2001 to 2010/2011 crop years. Results obtained with CM indicate that its application is able to generate timely production estimates for soybean both at municipality and local levels. Validation estimates with CM at State level obtained R2 = 0.95. Combining all cropping years at municipality level, estimates were highly correlated to official statistics from IBGE, with R2 = 0.91 and RMSD = 10,840 tons. Spatially interpolated comparisons of yield maps obtained from the CM estimates and IBGE data also showed visual similarity in their spatial distribution. Local level comparisons were performed and presented R2 = 0.95. Implications of this work point out that time-series analysis of production estimates are able to provide anticipated spatial information prior to the soybean harvest.
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