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51.
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   
52.
As(V) removal using carbonized yeast cells containing silver nanoparticles   总被引:1,自引:0,他引:1  
The present study involves the development of adsorbent containing silver nanoparticles for arsenate removal using silver reducing property of a novel yeast strain Saccharomyces cerevisiae BU-MBT-CY1 isolated from coconut cell sap. Biological reduction of silver by the isolate was deduced at various time intervals. The yeast cells after biological silver reduction were harvested and subjected to carbonization at 400 °C for 1 h and its properties were analyzed using Fourier Transform Infra-Red spectroscopy, X-ray diffraction, scanning electron microscope attached with energy dispersive spectroscopy and transmission electron microscope. The average size of the silver nanoparticles present on the surface of the carbonized silver containing yeast cells (CSY) was 19 ± 9 nm. The carbonized control yeast cells (CCY) did not contain any particles on its surface. As(V) adsorption efficiency of CCY and CSY was deduced in batch mode by varying parameters like contact time, initial concentration, and pH. Desorption studies were also carried out by varying the pH. The experimental data were fitted onto Langmuir and D-R Isotherms and Lagergren and pseudo second order kinetic models. The CSY was more efficient in arsenate removal when compared to CCY.  相似文献   
53.
Transdermal drug delivery has given cardinal contribution to medical practices. First-generation transdermal delivery of small, lipophilic, low-dose drugs and second-generation delivery systems using chemical enhancers, non-cavitational ultrasound and iontophoresis have also resulted in various clinical products provides added functionality. Third-generation delivery systems using microneedles, thermal ablation, microdermabrasion, electroporation and cavitational ultrasound targeting skin’s barrier layer of stratum corneum. Microneedles acquire pronounced intrigue in recent days. Currently, microneedles are advancing through clinical trials for delivery of macromolecules and vaccines, such as insulin, parathyroid hormone and influenza vaccine. The review explains about the concept of transdermal drug microneedle system comprising of microreservoir, micropumps, flow sensors, types of microneedles. Various researches carried out on these components of microneedle system is elaborately discussed in this review.  相似文献   
54.
The study of agglomerate strength is of vital importance in several industrial applications such as pharmaceutical, detergent and food manufacturing. Agglomerates could experience a size reduction during the production and handling processes due to collisions with other agglomerates or with the moving components and walls as well as during bulk flow due to shear deformation. In this analysis, we focus on the agglomerate damage due to oblique impact on walls, as this is a common damage process during, for example, pneumatic conveying and size reduction in pin mills.

Computer simulations have been carried out using Distinct Element Analysis, where the breakage characteristics of oblique impacts and the effect of the interparticle bond strength have been analysed. The procedure adopted here provides an isotropic and spherical agglomerate (uniform mass distribution and coordination number within radial segments of the agglomerate). The results indicate that the damage ratio (i.e. the number fraction of the broken bonds) depends on the normal component of the impact velocity only, i.e. the tangential component has little effect. However, the position of the clusters produced on impact does depend on the impact angle, which influences the pattern of breakage and in turn the size distribution of the large clusters.  相似文献   

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56.
We provide a response to a commentary by Wiers and Stacy (see record 2009-24669-003) on our model of the alcohol–behavior link (see record 2009-09537-002). Whereas Wiers and Stacy generally supported our model, they took issue with our conceptualization of the alcohol expectancy construct. We address the major concerns of Wiers and Stacy by demonstrating that our own view is consistent with basic cognitive scientific conceptualizations of the nature of associative and propositional reasoning within a dual-systems framework. In clarifying these issues, we maintain that although the predictions presented by Wiers and Stacy are important and useful in this area, they are predictions that can be derived from our original formulation of the alcohol–behavior link. We conclude that this kind of useful debate can only aid the generation of conceptually consistent and testable models that will advance the understanding of the alcohol–behavior link. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
Vehicle-to-Vehicle and Vehicle-to-Roadside communications are going to become an indispensable part of the modern day automotive experience. For people on the move, vehicular networks can provide critical network connectivity and access to real-time information. Infostations play a vital role in these networks by acting as gateways to the Internet and by extending network connectivity. In this context, an important question is “What is the minimum number of infostations that need to be deployed in an area in order to support vehicular applications?” Optimizing infostation density is vital to understanding and reducing the cost of deployment and management. In this paper, we examine the required infostation density in a highway scenario using different data dissemination models. We start from a simple analysis that captures the required density under idealized assumptions. These models are validated by an event-driven simulator. We then run detailed QualNet simulations on both controlled and realistic vehicular traces to observe the information density trends in practical environments, and consequently propose techniques to improve dissemination performance and reduce the required infostation density.  相似文献   
58.
Reviews the book, Generalized anxiety disorder: From science to practice by Michel J. Dugas and Melisa Robichaud (2006). The reviewers commend the authors for providing a comprehensive overview of GAD. Chapters include information on diagnosis, assessment techniques and treatment modules. Dugas and Robichaud refer to their treatment as primarily cognitive and emphasize the difference between their approach and other cognitive and cognitive-behavioural treatments for GAD. The treatment presented does not employ relaxation training or other strategies to reduce physical tension and overarousal. Rather, this treatment makes use of specific cognitive interventions with the understanding that physical and affective symptoms will decrease with corresponding reductions in excessive worry. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
The pH within individual organelles of the secretory pathway is believed to be an important determinant of their biosynthetic activity. However, little is known about the determinants and regulation of the pH in the secretory organelles, which cannot be readily accessed by [H+]-sensitive probes. We devised a procedure for the dynamic, noninvasive measurement of pH in the lumen of the endoplasmic reticulum in intact mammalian cells. A recombinant form of the B subunit of Shiga toxin, previously modified to include a carboxyl-terminal KDEL sequence and a pH-sensitive fluorophore, was used for a two-stage delivery strategy. Retrograde traffic of endogenous lipids was harnessed to target this protein to the Golgi complex, followed by retrieval to the endoplasmic reticulum (ER) by KDEL receptors. Immunofluorescence and immunoelectron microscopy were used to verify the subcellular localization of the modified B fragment. Fluorescence ratio imaging and two independent calibration procedures were applied to determine the pH of the ER in situ. We found that the pH of the endoplasmic reticulum is near neutral and is unaffected during agonist-induced release of calcium. The ER was found to be highly permeable to H+ (equivalents), so that the prevailing [H+] is susceptible to alterations in the cytosolic pH. Plasmalemmal acid-base transporters were shown to indirectly regulate the endoplasmic reticulum pH.  相似文献   
60.
The concept of implementation of Six Sigma methodology was pioneered at Motorola in the 1980s with the aim of reducing quality costs. Six Sigma methodology has evolved into a statistically oriented approach to process, product or service quality improvement. It is a business performance improvement strategy used to improve profitability, to drive out waste in business processes and to improve the efficiency of all operations that meet or exceed customers' needs and expectations. A performance level of Six Sigma equates to 3-4 defects per million opportunities, where sigma is a statistical measure of the amount of variation around the process average. The average sigma level for most companies is three sigma. The authors offer guidance as to how companies may achieve Six Sigma performance. Organisations that have adopted the principles and concepts of Six Sigma methodology have realised that once they have achieved Five Sigma quality levels the only way to surpass the Five Sigma quality level is to redesign their products, processes and services from scratch. These circumstances have led to the development of what we call today 'design for Six Sigma'. Design for Six Sigma is a powerful approach to designing products, processes and services in a cost-effective and simple manner, to meet the needs and expectations of the customer  相似文献   
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