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81.
82.
Masoud Haveshki Mahboobeh Mohamadhasani 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(4):737-738
Jun et al. (Bull Korean Math Soc 35(1):53–61, 1998) introduced the notion of associative filters in lattice implication algebra and studied some of its properties. In this
paper, we show that there is no associative filter in lattice implication algebra. 相似文献
83.
Hamid Reza Rajabi Mojtaba Shamsipur Seied Mahdi Pourmortazavi 《Materials science & engineering. C, Materials for biological applications》2013,33(6):3374-3381
This work reports the first application of the ion imprinting technology for determination of potassium ion by precipitation polymerization method. Ion imprinted polymeric (IIP) nanoparticles were prepared by using dicyclohexyl 18C6 (DC18C6) as a K+ ion selective crown ether, in the acetonitrile–dimethylsulfoxide (3:1; v/v) mixture as porogen. The imprint potassium ion was removed from the polymeric matrix using 0.5 M HNO3. The scanning electron microscopy (SEM) micrographs showed colloidal nanoparticles of 60–90 nm in diameter and slightly irregular in shape. The obtained ion-imprinted particles for K+ showed selective recognition with rapid adsorption and desorption processes. It was found that imprinting results in increased affinity of the material toward K+ ion over other competitor metal ions with the same charge and/or close ionic radius. The synthesized IIP nanobeads were shown to be promising for solid-phase extraction coupled with flame photometry for determination of trace K+ ion in different water samples. 相似文献
84.
A practical population balance model was used to evaluate the bubble size distribution in a bubble column. In addition, the bubble size distribution in the bubble column was measured at different gas velocities by photography and analysis of the pictures. Four types of liquid, i.e., water and three petroleum‐based liquids, were used in the experiments. The gas phase was air. It was found that the existing models in the literature are not able to satisfactorily predict the experimentally measured bubble size distribution. The model can be corrected by applying a correction factor to the energy dissipation rate. The corrected model fits the experimental bubble size distribution considerably better than the existing models. The variation of this correction factor is reported for different systems at different gas velocities. 相似文献
85.
This paper presents a real-time system for pedestrian tracking in sequences of grayscale images acquired by a stationary camera. The objective is to integrate this system with a traffic control application such as a pedestrian control scheme at intersections. The proposed approach can also be used to detect and track humans in front of vehicles. Furthermore, the proposed schemes can be employed for the detection of several diverse traffic objects of interest (vehicles, bicycles, etc.) The system outputs the spatio-temporal coordinates of each pedestrian during the period the pedestrian is in the scene. Processing is done at three levels: raw images, blobs, and pedestrians. Blob tracking is modeled as a graph optimization problem. Pedestrians are modeled as rectangular patches with a certain dynamic behavior. Kalman filtering is used to estimate pedestrian parameters. The system was implemented on a Datacube MaxVideo 20 equipped with a Datacube Max860 and was able to achieve a peak performance of over 30 frames per second. Experimental results based on indoor and outdoor scenes demonstrated the system s robustness under many difficult situations such as partial or full occlusions of pedestrians 相似文献
86.
Analyzing data from well logs and seismic is often a complex and laborious process because a physical relationship cannot be established to show how the data are correlated. In this study, we will develop the next generation of “intelligent” software that will identify the nonlinear relationship and mapping between well logs/rock properties and seismic information and extract rock properties, relevant reservoir information and rules (knowledge) from these databases. The software will use fuzzy logic techniques because the data and our requirements are imperfect. In addition, it will use neural network techniques, since the functional structure of the data is unknown. In particular, the software will be used to group data into important data sets; extract and classify dominant and interesting patterns that exist between these data sets; discover secondary, tertiary and higher-order data patterns; and discover expected and unexpected structural relationships between data sets. 相似文献
87.
Masoud Salavati-Niasari Faezeh Soofivand Ali Sobhani-Nasab Maryam Shakouri-Arani Masood Hamadanian Samira Bagheri 《Journal of Materials Science: Materials in Electronics》2017,28(20):14965-14973
In this work, CdTiO3 nanoparticles were synthesized through reaction between Cd(CH3COO)2.2H2O, Ti(OC4H9)4, trimesic acid as a new chelating agent and ethanol as solvent by Pechini sol–gel method. X-ray diffraction (XRD) patterns showed that CdTiO3 nanostructures have rhombohedral structure with diameter of about 35.61 nm. The structure, morphology and size of CdTiO3 nanoparticles were characterized by FT-IR, XRD, SEM and EDAX. The optical properties of the products were studied by DRS. Based on the results of experiments, it was found that temperature and time of calcination, pH and the solvent of reaction are important parameters for formation of CdTiO3 nanoparticles. Utilizing trimesic acid (benzene-1,3,5-tricarboxylic acid) as a new chelating agent for preparation of CdTiO3 nanostructures was initiative of this work. 相似文献
88.
Azam Sobhani Masoud Salavati-Niasari 《Journal of Materials Science: Materials in Electronics》2016,27(4):3271-3280
In this article, the synthesis and characterization of Co2P/Co nanocomposites are reported. Three kinds of precursors are studied: bis(salicylidene)cobalt(II) [Co(sal)2], bis(salicylate)cobalt(II) [Co(Hsal)2] and cobalt oxalate [Co(O4C2)·4H2O]. The cobalt(II) acetate tetrahydrate Co(CH3COO)2·4H2O is used as reference. The nanocomposites are prepared by thermal decomposition method using triphenylphosphine as a surfactant solvent and phosphorus precursor. A possible mechanism of the formation of the nanocomposites is put forward to explain the experimental observations. This is the first time that Co2P/Co nanocomposites are synthesized. To study the crystalline structure, composition, size, morphology and magnetic property of the products, characterization techniques including XRD, SEM, TEM, FT-IR and VSM are employed. 相似文献
89.
Mostafa Rajabi Mashhadi M. Hossein Javidi D. B. M. Sadegh Ghazizadeh 《Electrical Engineering (Archiv fur Elektrotechnik)》2011,93(3):117-126
Frequency control, as an ancillary service, is usually provided by generation reserves. Modern generating units have special
technical capabilities; e.g., their governor operation mode can be selected to be either active or passive, their ramp rate
can be selected to be either normal or fast, etc. On the other hand, generating units have some technical constraints; e.g.
some generating units cannot participate in primary frequency control at their capacity limits. In this paper, operational
capabilities and constraints of generating units are incorporated in a “simultaneous scheduling of energy and primary reserve”
problem. Furthermore, a heuristic iterative method (based on genetic algorithm) is proposed to obtain the optimal scheduling.
The impacts of capabilities and constraints on scheduling are investigated through simulation studies. Simulation results
depicts that taking these capabilities and constraints of generating units into account, not only reduces the total operational
cost of generating units, but also will end up with a feasible solution for the system, even in cases where the previously
proposed methods fail. 相似文献
90.
Abdolkarim Abbaspour Leila Baramakeh S. Masoud Nabavizadeh 《Electrochimica acta》2007,52(14):4798-4803
The electrocatalytic oxidation of guanine and DNA is demonstrated on a sol-gel coated carbon screen printed electrode modified with {MeReO(edt)}2 using cyclic and differential pulse voltammetric techniques. An oxidation peak at 370 mV was found, but no corresponding reduction peaks could be detected in the negative scan, which indicates that the oxidation of guanine is completely irreversible process. The oxidation peak potentials are shifted to more negative values with increasing pH. The utility of applying the sensor for determination of guanine and ss-DNA were investigated. The linear ranges were 0.19-10.8 and 0.45-7.8 μg ml−1 for guanine and DNA, respectively. Detection limits of 0.1 and 0.32 μg ml−1 were obtained for guanine and ss-DNA, respectively. 相似文献