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91.
R Basheer JE Sherin CB Saper JI Morgan RW McCarley PJ Shiromani 《Canadian Metallurgical Quarterly》1997,17(24):9746-9750
We investigated the effects of sleep on wake-induced c-fos expression in the cerebral cortex of rats and c-fos-lacZ transgenic mice. In the cortex of rats, the levels of c-Fos, detected both by immunocytochemistry and Western blot, remained high during 6 or 12 hr of enforced wakefulness but declined rapidly (within 1 hr) with increasing time of recovery sleep. Similarly, in the transgenic mice in which lacZ expression is driven from the c-fos promoter, beta-galactosidase activity was high after enforced wakefulness and declined with increasing amounts of sleep. These results suggest that the decrease in c-Fos protein in cortical neurons during sleep may be attributable to cessation of c-fos expression, activation of a process that degrades the wake-induced c-Fos, or both. 相似文献
92.
Multiple Resource-Constrained Scheduling Using Branch and Bound 总被引:7,自引:0,他引:7
This paper focuses upon the problem of assigning feasible start times to a set of activities making up a project, static job shop, or static flowship type schedules under two constraint sets: (1) no activity may be started until all activities technologically established as its predecessor set have been completed, and (2) the total resource requirements of all activities in process at any time in the schedule must not exceed the level of availability for each of the multiple resource classes. The solution procedure used for these problems is branch and bound, and the resulting complete schedules are optimized with an objective of minimizing the completion time of the entire set of activities. Computational results on tests conducted on a number of randomly generated problem sets with up to 60 activities and six resource classes are presented. 相似文献
93.
94.
Thermal-Lens Study on the Distance-Dependent Energy Transfer from Rhodamine 6G to Gold Nanoparticles
B. Rajesh Kumar N. Shemeena Basheer Achamma Kurian Sajan D. George 《International Journal of Thermophysics》2013,34(10):1982-1992
A study on energy transfer from the Rhodamine 6G (donor) to gold nanoparticles (acceptor) is investigated using a laser-based dual-beam thermal-lens technique. The nanoparticles are observed to quench the intrinsic fluorescence of the dye molecule via a nonradiative energy transfer mechanism. The influence of nanoparticle concentration $(0.09\,\hbox {nM}\,\hbox {to}\,0.24\,\hbox {nM})$ on the energy transfer mechanism with Rhodamine 6G $(1\;\upmu \hbox {M})$ is investigated. Analysis of the results indicates that the energy transfer efficiency is high (more than 50 %) in the presence of nanoparticles and the efficiency is enhanced with an increase in the nanoparticle concentration. The distance between the nanoparticle and dye molecule is evaluated on the basis of the nanomaterial surface energy transfer model. The thermal-lens studies probe the nonradiative path of de-excitation of the excited molecule, and the comparison between this technique and the conventional fluorescence method in measuring the distance as well as the energy-transfer efficiency clearly indicates that the thermal-lens technique is a complementary approach to study the energy-transfer mechanism between a donor and an acceptor. 相似文献
95.
Basheer Noaman Hussein Nasri Sulaiman R. K. Raja Ahmad Mohammad Hamiruce Marhaban 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(6):577-584
In this paper, a particle swarm optimization (PSO) method is proposed to design an optimal robust fuzzy logic controller (FLC). The objective of this paper is to design a nonlinear optimal robust controller for the single axis magnetic levitation system with high accuracy. PSO algorithm is applied to search globally optimal parameters of FLCs. Three different FLCs are designed. First, proportional derivative (PD)‐like FLC. Second, the FLC is based on the PSO algorithm to find the optimal range of the eight linguistic membership functions (FLC1 with PSO algorithm). Finally, the FLC is based on the PSO algorithm to find the optimal range and shape of the four linguistic membership functions (FLC2 with PSO algorithm). The performances of three different FLCs are compared. Simulation results show that PSO‐based optimal FLCs find the optimal range and shape of the four linguistic membership functions and achieved better performance than the other proposed controllers, minimizing 48 fuzzy rules. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
96.
The low yield and high salinity of the water product have limited the use of directional solvent extraction desalination method to the treatment of only low salinity water. In this research, in situ ultrasound enhancement of octanoic acid solvent extraction desalination is reported. The pre-prepared 3.5% (w/w) of saltwater solution and octanoic acid were mixed at five different temperatures which resulted in two phases. The performance of extraction for each set was evaluated based on salinity, yield of the recovered water, and solvent residual in the product water. The calculated yield of pure water under the ultrasound effects was higher than that without the ultrasound. This is due to the role of ultrasound in weakening the intermolecular interaction to dissociate water from salt, increasing the solvent efficiency in extracting water. The recovered water salinity was lower by using the ultrasound which can be explained as result of increasing the water yield. 相似文献
97.
In situ TiB2 reinforced Al 6063 composites have been successfully synthesized through the chemical reaction between Al–10%Ti and Al–3%B master alloys in the Al 6063 alloy using liquid metallurgy route. The amount of TiB2 formed in the composite is estimated using gravimetric analysis. Mechanical properties in terms of microhardness, ultimate tensile strength and modulus of elasticity have been improved by 21%, 47% and 65% respectively in comparison with matrix alloy. Further, ductility in terms of percentage elongation of the composites was found to increase by about 368% when compared with the matrix alloy. The improvement in ductility may be associated with the grain refinement of the composite with an increase in the content of Al–3%B master alloy. 相似文献
98.
A. Riaz Ahamed P. Asokan S. Aravindan 《The International Journal of Advanced Manufacturing Technology》2009,44(5-6):520-528
Hybrid metal matrix composites are a class of material system, with two or more discrete particulate reinforcement. Notwithstanding their superior properties, their widespread application is constrained by the difficulty in machining them. Non-conventional processes such as electrical discharge machining can be applied to machine such composites. This work reports on the application of EDM to machine cast aluminum–silicon carbide–boron carbide and cast aluminum–silicon carbide–glass hybrid metal matrix composites and how the metal removal rate and surface finish vary in response to the various EDM parameters 相似文献
99.
A set of mobile devices that employs wireless transmission for communication is termed Mobile Ad hoc Networks (MANETs). Offering better communication services among the users in a centralized organization is the primary objective of the MANET. Due to the features of MANET, this can directly End-to-End Delay (EED) the Quality of Service (QoS). Hence, the implementation of resource management becomes an essential issue in MANETs. This paper focuses on the efficient Resource Allocation (RA) for many types of Traffic Flows (TF) in MANET. In Mobile Ad hoc Networks environments, the main objective of Resource Allocation (RA) is to process consistently available resources among terminals required to address the service requirements of the users. These three categories improve performance metrics by varying transmission rates and simulation time. For solving that problem, the proposed work is divided into Queue Management (QM), Admission Control (AC) and RA. For effective QM, this paper develops a QM model for elastic (EL) and inelastic (IEL) Traffic Flows. This research paper presents an AC mechanism for multiple TF for effective AC. This work presents a Resource Allocation Using Tokens (RAUT) for various priority TF for effective RA. Here, nodes have three cycles which are: Non-Critical Section (NCS), Entry Section (ES) and Critical Section (CS). When a node requires any resources, it sends Resource Request Message (RRM) to the ES. Elastic and inelastic TF priority is determined using Fuzzy Logic (FL). The token holder selects the node from the inelastic queue with high priority for allocating the resources. Using Network Simulator-2 (NS-2), simulations demonstrate that the proposed design increases Packet Delivery Ratio (PDR), decrease Packet Loss Ratio (PLR), minimise the Fairness and reduce the EED. 相似文献
100.
Ahanger Tariq Ahamed Tariq Usman Nusir Muneer Aldaej Abdulaziz Ullah Imdad Sulman Abdullah 《The Journal of supercomputing》2022,78(2):1783-1806
The Journal of Supercomputing - Rapid communication of viral sicknesses is an arising public medical issue across the globe. Out of these, COVID-19 is viewed as the most critical and novel... 相似文献