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91.
The present study carries out measurements and evaluations of whole‐body vibration (WBV) exposure in drivers of a cargo vehicle composition, traveling under different conditions of roads and loading, to compare and assess the health risk through the various criteria provided by vibration exposure standards. Using the acceleration data measured in the seat, the WBV exposure of the drivers is evaluated according to the criteria provided by five standards: three different versions of ISO 2631 (Part 1, 1985 and 1997; Part 5, 2004), the European Directive 2002/44/EC and the new Brazilian regulation NR‐15 published in 2014. Comparisons investigating the differences between the standards are presented. The results of the experimental data indicate that the current version of the NR‐15 is more restrictive than the other standards considered in this paper. Thus, these results can contribute to improve the criteria used in the new NR‐15.  相似文献   
92.

In recent years, the phenomenon of eSports has been a growing trend and consequently, in addition to players, other groups of users, including coaches and analysts, took an interest in online video games and the data extracted from them. Among many types of video games, one of the most widely played is the MOBA (Multiplayer Online Battle Arena) League of Legend (LoL) game. Similary to traditional sports, players and coaches/analysts analyse all game events, such as, players’ movements, to understand how they play to define new strategies and improve their performance. Our main goal is to get a better understanding of which visualizations techniques are more adequate to handle this type of spatio-temporal information data, associated to player performance analysis in video games. To address this goal, we inquired players to identify the analytical questions they need to support for performance analysis and designed the VisuaLeague prototype for the visualization of in-game player trajectories, using animated maps, and events during a LoL match. This paper presents a user study to evaluate the adequacy of animated maps and the analytical strategies followed by players when using spatio-temporal data to analyse player performance. The results support the adequacy of using the animated maps technique to convey information to users in this context. Moreover, they also point out towards a high degree of importance given to the spatio-temporal components of the data for player performance analysis.

  相似文献   
93.
This paper presents a control algorithm for reducing heat losses caused by clouds in large solar fields. The formulation is based on a Mixed Logical Dynamical (MLD) representation of the solar field plus the application of a Practical Nonlinear Model Predictive Controller (PNMPC) for calculating the optimal control action. The main purpose of the controller is to deactivate fields with inlet temperature greater than outlet temperature and to manipulate the oil flow rate of the activated fields for tracking the reference of the outlet temperature. A simplified lumped parameters model is used for prediction and simulation of the solar fields.  相似文献   
94.
95.
We propose and evaluate a system for content-based visualization and exploration of music collections. The system is based on a modification of Kohonen’s Self-Organizing Map algorithm and allows users to choose the locations of clusters containing acoustically similar tracks on the music space. A user study conducted to evaluate the system shows that the possibility of personalizing the music space was perceived as difficult. Conversely, the user study and objective metrics derived from users’ interactions with the interface demonstrate that the proposed system helped individuals create playlists faster and, under some circumstances, more effectively. We believe that personalized browsing interfaces are an important area of research in Multimedia Information Retrieval, and both the system and user study contribute to the growing work in this field.  相似文献   
96.
Software and Systems Modeling - In recent years, there has been a growing interest in the use of reference conceptual models to capture information about complex and sensitive business domains...  相似文献   
97.
98.
Internet technologies are constantly evolving as well as the way people use them. Search engines help users to find higher and better relevant results to their searches. Cloud Computing is an evolution of the Internet services and provides a step further ecosystem that can be used to improve the search of more relevant results. Each search engine is based on different modules in order to retrieve the results expected by users using specific keywords. Social networks appear as a reliable Web technology that can directly support a content search. Several studies have been performed showing the growth of social networks in people lives. Using the cloud computing paradigm it is possible to propose a more scalable and efficient way to explore public information available on online social networks. This paper includes the analyses of several social networks services, available contents, cloud-crawlers, and information extraction. In order to collect relevant data from social networks, a social crawler on cloud is proposed. The new approach provides a cloud-based crawler for low-cost, effective, and personalized search models. Moreover, a new algorithm to rank Web documents is proposed and demonstrated. The proposed system is evaluated in comparison with the top Internet search engine, Google, its behavior is very promising, and it is ready for use.  相似文献   
99.
Internalization of biocompatible magnetic nanoparticles by red blood cells (RBCs) is a key issue for opportunities of new applications in the biomedical field. In this study, we used in vitro tests to provide evidences of magnetic nanoparticle internalization by mice red blood cells. The internalization process depends upon the nanoparticle concentration and the nanoparticle hydrodynamic radii. The cell internalization of surface-coated maghemite nanoparticles was indirectly tracked by Raman spectroscopy and directly observed using transmission electron microscopy. The observation of nanoparticle cell uptaking using in vitro experiments represents an important breakthrough for the application of nanomagnetism in diagnosis and therapy of RBC-related diseases.  相似文献   
100.
A new concentration procedure using an immunofiltration-based method is described. The approach enables quantitative determination of organic pollutants by filtering large volumes of sample through a poly(vinylidene difluoride) membrane where antibodies have been immobilized by passive adsorption. The analysis is based on a sequential competitive enzyme immunoassay. A wide range of sample volumes have been tested (0.2-5.0 mL) for each type of antibody. The improvement on the assay sensitivity and specificity achieved by means of this concentration procedure is discussed. Using this technique and the insecticide carbaryl as a model analyte, a concentration factor of at least 13 and a limit of detection of 4.75 ng/L are accomplished. The suitability of this methodology is demonstrated by the quantification of the insecticide in several types of water samples (bottled, estuarine, and physiological-saline solutions) with recoveries ranging between 102 and 111%. This method has proved to concentrate carbaryl directly, in an accurate way, for residue analysis without using organic solvents or any extraction process. Furthermore, this procedure offers the advantages of carrying out in the same system both preconcentration and quantitative determination of the analyte.  相似文献   
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