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Multimedia Tools and Applications - The medical image processing has become indispensable with an increased demand for systematic and efficient detection of brain tumor in a short period of time....  相似文献   
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The software-defined network (SDN) is one of the network architectures, in which the data plane and control plane is divided from each other, and the network can be handled using a sensibly centralized controller and this method is adopted to reconfigure the wireless sensor network automatically. In this article, to implement the SDN in MANET, in which control nodes can be chosen in SDN dynamically for the activation of MANET function to allocate the works to other mobile nodes to the base station. However, in the field of mobile ad hoc networks, the network lifetime, and battery lifetime is one of the major problems and the energy consumption can play a significant rule for the transmission of data in the SDN. Therefore, in this article, particle swarm optimization (PSO) based CGSR (cluster-head gateway switch routing protocol) algorithm with fuzzy rules is proposed to increase the network lifetime of battery powered mobile nodes by reducing the energy consumptions of each node in software-defined MANET. In this proposed method, a routing method that can permit various mobile nodes with low battery power to transmits the data from source node to base station. We design a PSO based CGSR routing protocol by selecting the routing mobile nodes using fuzzy rules for packet transmission. In CGSR process, the formation of cluster and selection of cluster head is executed depending on the particle swarm optimization method. This proposed routing protocol can be used to enhance the battery lifetime by extension of the network lifetime with numerical analysis for efficient route node selection.  相似文献   
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The sawdust (SD) waste generated in the timber industry was converted to a low‐cost activated carbon (SDAC) using a simpler and cheaper activation process, single‐step steam pyrolysis activation. The possibility of utilizing SDAC for the removal of lead (Pb(II)) in the absence of ligands and nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA) chelated Pb(II) complexes from the liquid phase was examined and the results were compared with those for commercial activated carbon (CAC). SDAC shows a high adsorption capacity for Pb(II) and Pb(II) chelates compared with CAC. The extent of adsorption of Pb(II) and Pb(II) chelates on activated carbons was found to be a function of solution pH and species distribution of Pb(II) and Pb(II) chelates. The optimum pH range for the removal of Pb(II) in the absence of ligands by SDAC was 6.5–8.0, whereas its maximum removal by CAC was observed at pH 6.5. In the presence of ligands, the extent of Pb(II) adsorption was enhanced in the pH range 2.0–5.0 and was reduced significantly in the pH range 6.0–8.0. The maximum uptake of Pb(II) chelates for both carbons was observed at pH 5.0. Kinetic models such as pseudo‐first‐order, pseudo‐second‐order and pore diffusion were tested to investigate the adsorption mechanism. Batch kinetic studies showed that the adsorption of Pb(II) from aqueous solutions with and without ligands could be best described by a psuedo‐first‐order model for both carbons. The effect of pH on the adsorption isotherms of Pb(II) and Pb(II) chelates was also investigated. The applicability of the Langmuir and Freundlich isotherms, established for various initial concentrations of the adsorbate and for different pH values, was tested at 30 °C. Copyright © 2003 Society of Chemical Industry  相似文献   
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A random search method, Optimized Step-Size Random Search (OSSRS), for function minimization is proposed. In this method the step-size is determined by fitting a quadratic for the function value in terms of the step-size in each of the random directions. The random direction is generated using a pseudorandom number generator with a normal distribution of zero mean and a given standard deviation.  相似文献   
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Values of hour excretion of vitamins B1, B2, B6 and PP with urine in children of 9-13 years, studied under conditions of normal consumption of these vitamins, were estimated considering the correlation between the vitamins B concentration in blood and excretion of their metabolites with urine as well as using these parameters dependence on content of the vitamins in daily ration; for this purpose 35 adult persons and 31 children of both sexes were examined. Normal rate of riboflavin excretion with urine constituted 10-11 micrograms/h in children of this age, while of thiamine-11-12 micrograms/h. Under conditions of normal thiamine consumption, activity of erythrocyte transketolase, measured after preinactivation of transaldolase, exceeded 35 mumol/h/I ml of erythrocytes. Rates of excretion with urine of 4-pyridoxic acid and I-methyl nicotinamide were similar both in children and in adult persons and were equal to more than 40 micrograms/h and 400-600 micrograms/h, respectively.  相似文献   
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