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241.
In the case of heavily reinforced concrete structural members, bundled bars are required rather than spaced bars. The use of spliced bundled bars is necessary when available bar lengths are limited. No design recommendations regarding the use of bundled or spliced bundled FRP bars are available. The results of four-point flexural testing of nine concrete beams reinforced with spliced bundled CFRP bars are presented herein. The effects of the type of bundle and splice length on the bond strength of bundled CFRP bars are investigated. Based on the experimental results, a procedure for determining the critical splice length of FRP bars is presented and the corresponding values of bond stresses can be predicted. Moreover, the ultimate strength analysis method is used to predict the maximum stress in spliced bundled CFRP bars. Finally, comparisons with the existing recommendations regarding the use of bundled steel bars and the recommended modifications for bundled CFRP bars are presented. 相似文献
242.
As a component of Wireless Sensor Network (WSN), Visual-WSN (VWSN) utilizes cameras to obtain relevant data including visual recordings and static images. Data from the camera is sent to energy efficient sink to extract key-information out of it. VWSN applications range from health care monitoring to military surveillance. In a network with VWSN, there are multiple challenges to move high volume data from a source location to a target and the key challenges include energy, memory and I/O resources. In this case, Mobile Sinks(MS) can be employed for data collection which not only collects information from particular chosen nodes called Cluster Head (CH), it also collects data from nearby nodes as well. The innovation of our work is to intelligently decide on a particular node as CH whose selection criteria would directly have an impact on QoS parameters of the system. However, making an appropriate choice during CH selection is a daunting task as the dynamic and mobile nature of MSs has to be taken into account. We propose Genetic Machine Learning based Fuzzy system for clustering which has the potential to simulate human cognitive behavior to observe, learn and understand things from manual perspective. Proposed architecture is designed based on Mamdani’s fuzzy model. Following parameters are derived based on the model residual energy, node centrality, distance between the sink and current position, node centrality, node density, node history, and mobility of sink as input variables for decision making in CH selection. The inputs received have a direct impact on the Fuzzy logic rules mechanism which in turn affects the accuracy of VWSN. The proposed work creates a mechanism to learn the fuzzy rules using Genetic Algorithm (GA) and to optimize the fuzzy rules base in order to eliminate irrelevant and repetitive rules. Genetic algorithm-based machine learning optimizes the interpretability aspect of fuzzy system. Simulation results are obtained using MATLAB. The result shows that the classification accuracy increase along with minimizing fuzzy rules count and thus it can be inferred that the suggested methodology has a better protracted lifetime in contrast with Low Energy Adaptive Clustering Hierarchy (LEACH) and LEACH-Expected Residual Energy (LEACH-ERE). 相似文献
243.
We characterized 12 isolates of Streptococcus pneumoniae with various levels of susceptibility of penicillin and extended-spectrum cephalosporins by antimicrobial susceptibility patterns, serotypes, ribotypes, chromosomal DNA restriction patterns by pulsed-field gel electrophoresis, multilocus enzyme electrophoresis patterns, penicillin-binding protein (PBP) profiles, and DNA restriction endonuclease cleavage profiles of pbp1a, pbp2x, and pbp2b. Seven cefotaxime-resistant (MIC, > or = 2 micrograms/ml) serotype 23F isolates were related on the basis of ribotyping, pulsed-field gel electrophoresis, and multilocus enzyme electrophoresis, but they had two slightly different PBP patterns: one unique to strains for which the MIC of penicillin is high (4.0 micrograms/ml) and one unique to strains for which the MIC of penicillin is low (0.12 to 1.0 micrograms/ml). The pbp1a and pbp2x fingerprints were identical for the seven isolates; however, the pbp2b fingerprints were different. An eighth serotype 23F isolate with high-level resistance to cephalosporins was not related to the other seven isolates by typing data but was a variant of the widespread, multiresistant serotype 23F Spanish clone. The PBP profiles and fingerprints of pbp1a, pbp2x, and pbp2b were identical to those of the Spanish clone isolate. An additional serotype 6B isolate with high-level resistance to cephalosporins had unique typing profiles and was unrelated to the serotype 23F cephalosporin-resistant isolates but was related on the basis of genetic typing methods to a second serotype 6B isolate that was cephalosporin susceptible. The serotype 6B isolates had different PBP profiles and fingerprints for pbp1a, but the fingerprints for pbp2x and pbp2b were the same. 相似文献
244.
Zeinab Rezaeifar Rasheed Hussain Sangjin Kim Heekuck Oh 《Wireless Personal Communications》2017,92(3):1011-1028
Electric vehicles (EVs) can be considered as a revolution in the combustion industry with significant improvement in fuel utilization and decrease in pollution compared to combustion engines. However, by decreasing the size of the battery to reduce the cost, the frequency of charging EVs in a day increases. Therefore, to reduce the downtime required for charging EVs, wireless charging on the move can be an effective solution. In such a situation, paying for wireless charging on the move is an important issue. However, it can endanger the location privacy of users, since the EVs need to charge frequently in a day. In this paper, we first explain different methods of payment and problems with such payment methods in the case of wireless charging on the move. Then, we propose an efficient payment method based on ‘tokens’ for wireless charging on the move, which minimizes the communications between service providers and users during the charging process. The proposed scheme prevents users and service providers from cheating, and it is robust to support different values for the price. Finally, we compare it with other payment methods that have been proposed for plug-in electric vehicles. 相似文献
245.
Nadeem Zain Khan Zainullah Mir Usama Mir Umer Iftikhar Khan Shahnawaz Nadeem Hamza Sultan Junaid 《Multimedia Tools and Applications》2022,81(6):8429-8449
Multimedia Tools and Applications - Initially, the traffic-sign recognition was done using the conventional image processing techniques which are sluggish and can cause fatal delays in real-world... 相似文献
246.
ABSTRACT Two different methods have been applied for the determination of captopril, namely,(i) a direct mercurimetric method using standard mercuric nitrate solution and diphenyl carbazone as an end-point indicator (ii) a differential pulse (DP50) polarographic method based on the measurement of the polarographic current at the peak potential of - 0.25V vs. Ag/AgCl (Kcl Sat.) reference electrode using acetate buffer of pH U.6 as a supporting electrolyte containing 0.01% w/v gelatin as a maximum suppressor. The accuracy obtained for the mercurimetric method is 99.8±0.7% and 100.2±1.3% for the authentic captopril and its tablets respectively. For the polarographic method, the linearity between current and concentration holds for the concentration range 2 to 45 ppm under the experimental conditions employed with an accuracy of 99. 4±0.8% and 99.9±1.9% for the authentic captopril and its tablets respectively. 相似文献
247.
Usama M. Attia Jeffrey R. Alcock 《The International Journal of Advanced Manufacturing Technology》2011,52(1-4):183-194
Microsystem technologies require relatively strict quality requirements. This is because their functionalities are usually dependent on stringent requirements of dimensions, masses or tolerances. When mass-producing micro-components, e.g. replication of disposable microfluidic diagnostics devices, the consistency of the produced components could be significantly affected by process variability. The variability could be associated with a specific process parameter or could be a result of process noise. This paper presents a methodology to assess and minimise process variability in micro-injection moulding, an example of well-established mass-production techniques for micro-components. A design-of-experiments approach was implemented, where five process parameters were investigated for possible effects on the process variability of two components. The variability was represented by the standard deviation of the replicated part mass. It was found that melt temperature was a significant source of variability in part mass for one of the components, whilst the other was affected by unsystematic variability. Optimisations tools such as response surfaces and desirability functions were implemented to minimise mass variability by more than 40%. 相似文献
248.
249.
T. Saidani M. Zaabat M. S. Aida R. Barille M. Rasheed Y. Almohamed 《Journal of Materials Science: Materials in Electronics》2017,28(13):9252-9257
Zinc oxide thin films were deposited by sol gel technique on glass substrates using different precursors (zinc acetate, zinc nitrate and zinc chloride). In the present work we investigate the precursor nature influence on structural, morphological, optical, electrical properties and photocatalytic activity of ZnO thin films. For this purpose we have used X-rays diffraction (XRD), atomic force microscopy (AFM), UV–visible spectroscopy and Hall effect measurements for films characterization. The obtained results indicated that ZnO films properties are strongly influenced by the nature of the used precursor as reactant. Films photocatalytic activity was evaluated by the photo-degradation of methylene blue (MB) dissolved in aqueous solution under UV-A light. The obtained results indicated that ZnO thin films prepared from zinc acetate are more efficient than those prepared from zinc nitrate and zinc chloride. 相似文献
250.
Generally, wind to power conversion is calculated by assuming the quality of wind as measured with a Weibull probability distribution at wind speed during power generation. We build on this method by modifying the Weibull distributions to reflect the actual range of wind speeds and wind energy density. This was combined with log law that modifies wind speed based on the height from the ground, to derive the wind power potential at windy sites. The study also provides the Levelized cost of renewable energy and hydrogen conversion capacity at the proposed sites. We have also electrolyzed the wind-generated electricity to measure the production capacity of renewable hydrogen. We found that all the sites considered are commercially viable for hydrogen production from wind-generated electricity. Wind generated electricity cost varies from $0.0844 to $0.0864 kW h, and the supply cost of renewable hydrogen is $5.30 to $ 5.80/kg-H2. Based on the findings, we propose a policy on renewable hydrogen fueled vehicles so that the consumption of fossil fuels could be reduced. This paper shall serve as a complete feasibility study on renewable hydrogen production and utilization. 相似文献