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991.
992.
993.
María Elena Escuderos Marino Uceda Sebastián Sánchez Antonio Jiménez 《European Journal of Lipid Science and Technology》2007,109(5):536-546
At present, two systems have been usually used to identify olive oil aroma: the official panel test, according to the European Union Regulation [1], and the gas chromatographic method and its improvements. However, both types of techniques have two principal disadvantages: They need a long time for analysis and cannot be applied on‐line. Recently, there has been increasing interest in the development of a new device, the so‐called “electronic nose”. The aim of this work is to perform both a review of these techniques used for olive oil sensory analysis and their advantages and disadvantages. 相似文献
994.
David Vallet Frank Hopfgartner Martin Halvey Joemon M. Jose 《Signal, Image and Video Processing》2008,2(4):289-306
In this paper, we present a novel approach to aid users in the difficult task of video search. We use a graph based model
based on implicit feedback mined from the interactions of previous users of our video search system to provide recommendations
to aid users in their search tasks. This approach means that users are not burdened with providing explicit feedback, while
still getting the benefits of recommendations. The goal of this approach is to improve the quality of the results that users
find, and in doing so also help users to explore a large and difficult information space. In particular we wish to make the
challenging task of video search much easier for users. The results of our evaluation indicate that we achieved our goals,
the performance of the users in retrieving relevant videos improved, and users were able to explore the collection to a greater
extent. 相似文献
995.
Amaya Romero Agustín Garrido Antonio Nieto-Mrquez Paula Snchez Antonio de Lucas Jos Luis Valverde 《Microporous and mesoporous materials》2008,110(2-3):318-329
In order to study the influence of the metal phase in the carbon yield and structural characteristics of carbon nanofibers (CNFs) synthesized by CVD over supported catalysts, different catalysts were prepared using iron, cobalt and nickel as active metal and zeolites Y and mordenite as support. The results showed that the metal precursor produced a great influence on the catalytic activity, fact that could be explained in according to the different solubility of carbon in the metals or in the differences in the diffusion and segregation of carbon through the metal particles. Characterization data of the solid carbon products revealed unique structures and textural properties as well as crystalline conditions on function of metal used. Additionally, support-metal interaction was evaluated, where experiments with similar nickel load over Y and mordenite zeolites were carried out, finding higher carbon yields and more ordered structures when Y zeolite was used. 相似文献
996.
Alan M.M. de Lima Roberto Schirru Fernando Carvalho da Silva José Antonio Carlos Canedo Medeiros 《Annals of Nuclear Energy》2008
The core of a nuclear Pressurized Water Reactor (PWR) may be reloaded every time the fuel burn-up is such that it is not more possible to maintain the reactor operating at nominal power. The nuclear core fuel reload optimization problem consists in finding a pattern of burned-up and fresh-fuel assemblies that maximize the number of full operational days. This is an NP-Hard problem, meaning that complexity grows exponentially with the number of fuel assemblies in the core. Moreover, the problem is non-linear and its search space is highly discontinuous and multi-modal. 相似文献
997.
998.
In this paper, model predictive control (MPC) is applied to the Italian 80 MWth experimental accelerator driven system (XADS), referring to a simple, non-linear model for the dynamic simulation of the plant, which has been developed and described in a previous work [A. Cammi, L. Luzzi, A.A. Porta, M.E. Ricotti, Prog. Nucl. Energ. 48 (2006) 578], in order to describe the interactions among the different subsystems: i.e., the accelerator-core coupling, the lead bismuth eutectic (LBE) primary system, the secondary system with diathermic oil and air coolers batteries, which reject the thermal power to the environment. Hereinafter, a model predictive controller is proposed, with the objective to minimize the difference between the average temperature of the diathermic oil and its reference value, while also minimizing the variations of the control input, which is the air coolers mass flow rate. The dynamic response of the LBE-XADS has been evaluated with reference to a reduction of 20% in the reactor power from nominal load conditions: this transient is very demanding for the overall plant, nevertheless the obtained results indicate the effectiveness of the proposed controller. 相似文献
999.
Antonio C. Silva Sonia Mello-Castanho Francisco Guitian Isabel Montero Antonio Esteban-Cubillo Isabel Sobrados Jesus Sanz Jose S. Moya 《Journal of the American Ceramic Society》2008,91(4):1300-1305
In the present investigation, a glassing process for galvanic waste (GW) incorporation with a high chemical stability is presented. Glasses with up to 50 wt% of galvanic solid waste by modifications in the basic composition of soda–lime–borosilicate glasses were prepared. After fusing at temperatures up to 1300°C, the glasses were characterized by inductively coupled plasma, scanning electron microscopy/energy-dispersive X-ray spectroscopy, high-temperature microscopy, transmission and reflected light microscopy, nuclear magnetic resonance, X-ray photoelectron spectroscopy, and X-ray diffraction methods. The chemical stability was evaluated by hydrolytic attack assays. Glasses containing up to 40 wt% of GW with a very high chemical stability, similar to bottle glasses, were obtained. 相似文献
1000.
Childers Donald G. Fischler Ira S. Boaz Timothy L. Perry Nathan W. Arroyo A. Antonio 《IEEE transactions on bio-medical engineering》1986,(12):1069-1075
We report on the effect of electrode placement and number of electrodes on the classification of single trial event related potentials (ERP's). The subjects read propositions relating fictitious people and their occupations while ERP's were recorded. The subjects decided if the proposition was correct or incorrect and responded as per instructions. The single trial, multichannel ERP data were classified using various methods, e. g., hold-out, leave-one-out, resubstitution. Several other factors were examined to determine their effect on ERP classification, including taking a majority vote among channels, using the single best channel, and averaging the data across channels for a single ERP. The results from other experiments are compared to those presented here. 相似文献