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Botega Leonardo Castro de Souza Jéssica Oliveira Jorge Fábio Rodrigues Coneglian Caio Saraiva de Campos Márcio Roberto de Almeida Neris Vânia Paula de Araújo Regina Borges 《Universal Access in the Information Society》2017,16(4):889-902
Universal Access in the Information Society - Situation Assessment (SA) approaches aim to provide powerful resources to support decision makers in enhancing their Situational Awareness (SAW). The... 相似文献
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Martin Olazar Roberto Aguado María J San Jos Javier Bilbao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(5):469-476
An original reactor (a conical spouted bed reactor) is used for the kinetic study of Pinus insignis sawdust pyrolysis in the range 400–500 °C under the usual conditions of this reactor for pyrolysis in a continuous regime. The equipment meets the requirements for pyrolysis kinetic study (bed isothermality, high mass and heat transfer between phases and short residence time of gaseous products). The results of yield of products are evidence of the good performance of the conical spouted bed reactor for obtaining a liquid product, with a maximum yield of 70 wt% in the range 440–460 °C. © 2001 Society of Chemical Industry 相似文献
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Inge S. Fomsgaard Helle Johannesen Jorge Pitty Roberto Rugama 《The International journal of environmental studies》2013,70(3):175-198
Sediment samples were collected at 5 sites in the Nicaraguan estuary “El Naranjo” in July 94 and September 94. The samples were incubated with 14C‐maneb (0.08 μg.g‐1 dw sediment), and evolved 14CO2 and residual 14C‐ETU in soil were measured. Mineralization kinetics of I4C‐maneb was best described with kinetic models which include growth of microorganisms. The amounts of 14C‐maneb mineralized were highest at the sites closest to the mouth of the river. No significant differences in degradation between July and September were seen. After 67 days between 9.73 and 16.18% of added 14C had evolved as 14CO2 in the July samples and after 150 days between 11.18 and 27.37% of added 14C had evolved as 14CO2 from the September samples. When 4.61–8.20% of added I4C was found in the soil extract, 0.00–2.72% was 14C‐ETU. 相似文献
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Rafael Díaz Aurora Hernndez Roberto Quintana Carmen Cabrera Ericka Díaz 《Catalysis Today》2001,65(2-4):373-380
Methyl tert-butyl ether (MTBE) synthesis is nowadays carried out using resin catalysts. An alternative zeolitic catalyst is presented in this study. This catalyst presents better mechanical and thermal strength, as well as slightly better performance. It is capable of enduring temperatures that would deactivate resin catalyst. The microkinetic study presented below indicates the importance of temperature and molar feed ratio depending on the catalyst used. Activation energy was found to be 15.7 kcal/g mol. Reaction mechanism suggested involved adsorption of isobutylene on two active sites and methanol on one active site. 相似文献
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The temperature‐time sequences to maintain constant the concentration of one product in a two‐parallel (competitive) exothermic reaction system undergoing catalyst deactivation are analyzed. Kinetics is described by a power law model and linear particle deactivation. A computational algorithm and a parametric study for adiabatic packed bed reactors are presented. It is found that temperature‐time trajectories are strongly influenced by mean activity, and the selectivity. Experimental information for Hydrotreating of vacuum gas oil was obtained keeping constant desulfurization, while hydrocracking and denitrogenation are function of time. Trajectories and final operating temperature are predicted with error below 2% compared to real operation. 相似文献
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Francisco José García-Peñalvo Ricardo Colomo-Palacios Juan García Roberto Therón 《Expert systems with applications》2012,39(13):11468-11478
Ontology creation and management related processes are very important to define and develop semantic services. Ontology Engineering is the research field that provides the mechanisms to manage the life cycle of the ontologies. However, the process of building ontologies can be tedious and sometimes exhaustive. OWL-VisMod is a tool designed for developing ontological engineering based on visual analytics conceptual modeling for OWL ontologies life cycle management, supporting both creation and understanding tasks. This paper is devoted to evaluate OWL-VisMod through a set of defined tasks. The same tasks also will be done with the most known tool in Ontology Engineering, Protégé, in order to compare the obtained results and be able to know how is OWL-VisMod perceived for the expert users. The comparison shows that both tools have similar acceptation scores, but OWL-VisMod presents better feelings regarding user’s perception tasks due to the visual analytics influence. 相似文献
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Future science-driven landing missions, conceived to collect in situ data on regions of planetary bodies that have the highest potential to yield important scientific discoveries, will require a higher degree of autonomy. The latter includes the ability of the spacecraft to autonomously select the landing site using real-time data acquired during the descent phase. This paper presents the development of an Evolutionary Fuzzy Cognitive Map (E-FCM) model that implements an artificial intelligence system capable of autonomously selecting a landing site with the highest potential for scientific discoveries constrained by the requirement of soft landing in a region with safe terrains. The proposed E-FCM evolves its internal states and interconnections as a function of real-time data collected during the descent phase, therefore improving the decision process as more accurate information becomes available. The E-FCM is constructed using knowledge accumulated by planetary experts and it is tested on scenarios that simulate the decision process during the descent phase toward the Hyndla Regio on Venus. The E-FCM is shown to quickly reach conclusions that are consistent with what would be the choice of a planetary expert if the scientist were presented with the same information. The proposed methodology is fast and efficient and may be suitable for on-board spacecraft implementation and real-time decision making during the course of robotic exploration of the Solar System. 相似文献