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61.
Hend Omar Mohamed Enas Taha Sayed M. Obaid Yun-Jeong Choi Sung-Gwan Park Siham Al-Qaradawi Kyu-Jung Chae 《International Journal of Hydrogen Energy》2018,43(46):21560-21571
The poor wettability and high cost of the carbonaceous electrodes materials prohibited the practical applications of microbial fuel cells (MFCs) on large scale. Here, a novel nanoparticles of metal sheathed with metal oxide is electrodeposited on carbon paper (CP) to introduce as high-performance anodes of microbial fuel cell (MFC). This thin layer of metal/metal oxide significantly enhance the microbial adhesion, the wettability of the anode surface and decrease the electron transfer resistance. The investigation of the modified CP anodes in an air-cathode MFCs fed by various biocatalyst cultures shows a significant improving in the MFC performance. Where, the generated power and current density was 140% and 210% higher as compared to the pristine CP. Mixed culture of exoelectrogenic microorganism in wastewater exhibited good performance and generated higher power and current density compared to yeast as pure culture. The excellent capacitance with a distinctive nanostructure morphology of the modified-CP open an avenues for practical applications of MFCs. 相似文献
62.
Abdul Khalib Zahereel Ishwar Ehtiba Farij Omar Ahmad R. Badlishah Salim Naseer Sabri Rahman Mostafijur Li Mingfu 《Multimedia Tools and Applications》2018,77(21):28799-28816
Multimedia Tools and Applications - Adaptive Media Playout (AMP) controls adapt playout rate to prevent buffer outage and to reduce delay in playout. Most AMP techniques use buffer fullness or its... 相似文献
63.
Omar Rabbani Munshoor Ahmed Saqib Zia 《Computers & Mathematics with Applications》2019,77(12):3195-3211
This paper focuses on implementation of space–time CE/SE scheme for computing the transport of a passive pollutant by a flow. The flow model comprises of the Saint-Venant system of shallow water equations and the pollutant propagation is described by a transport equation. The one-dimensional and two-dimensional flow equations are numerically investigated using the CE/SE scheme. A number of test problems are presented to check the accuracy and efficiency of the proposed scheme. The results of CE/SE scheme are compared with the central scheme. Both the schemes are found to be in close agreement. However, our proposed CE/SE scheme accurately captures shocks and discontinuous profiles. 相似文献
64.
65.
The main aim of this experimental work is to find out possible improvement in thermal protective performance of firefighter protective clothing when subjected to different level of radiant heat flux density. Firefighter protective clothing normally consists of three layers: outer shell, moisture barrier and thermal liner. When thermal protective performance of firefighter protective clothing is enhanced, the time of exposure against radiant heat flux is increased, which will provide extra amount of time to firefighter to carry on their work without suffering from severe skin burn injuries. In this study, the exterior side of outer shell was coated with nano-silver metallic particle through magnetron sputtering technology. Coating of outer shell with nano-silver particles was performed at three level of thickness, i.e. 1, 2 and 3?µm, respectively. All the uncoated and silver coated specimens were then characterized on air permeability tester, Permetest and radiant heat transmission machine. It was observed that coating has insignificant difference on the air and water vapor permeability of specimen and a significant decline was recorded for the value of transmitted heat flux density Qc (kW/m2) and percentage transmission factor (%TF Qo) as compared to uncoated specimen when subjected to 10 kW/m2 and 20?kW/m2 indicating improvement of thermal protective performance. These values go on further reduction with increase in thickness of coating layer of nano-silver particles. 相似文献
66.
Omar Hernández-González Mondher Farza Tomas Ménard Mohammed M'Saad Rogelio Lozano 《International journal of systems science》2019,50(5):1089-1105
This paper proposes a new high gain observer for a class of non-uniformly observable nonlinear systems with coupled structure driven by sampled outputs. The considered class of systems is particularly constituted by several subsystems where each subsystem is associated to a subset of the output variables. The observer design is carried out through two steps. First, a high-gain observer is proposed in the continuous-time output case under the assumption that an adequate persistent excitation condition is satisfied by each subsystem. Then, the proposed observer is redesigned to handle the case of sampled outputs leading thereby to a continuous-discrete time observer. The latter property is achieved thanks to the approach pursued along the convergence analysis. The effectiveness of the proposed observer is emphasised in a realistic simulation framework involving a mathematical model of a quadrotor which is diffeomorphic to the proposed class of considered systems. 相似文献
67.
68.
Sajid Bashir Muhammad Naeem Adnan Ahmed Khan Syed Ismail Shah 《International Journal of Communication Systems》2010,23(1):109-124
The paper discusses a sequence detector based on univariate marginal distribution algorithm (UMDA) that jointly estimates the symbols transmitted in a multiple input multiple output (MIMO) communication system. While an optimal maximum likelihood detection using an exhaustive search method is prohibitively complex, it has been shown that sphere decoder (SD) achieves the optimal bit error rate (BER) performance with polynomial time complexity for smaller array sizes. However, the worst‐case complexity of SD is exponential in the problem dimensions, this brings in question its practical implementation for larger number of spatial layers and for higher‐order signal constellation. The proposed detector shows promising results for this overly difficult and complicated operating environment, confirmed through simulation results. A performance comparison of the UMDA detector with SD is presented for higher‐order complex MIMO architectures with limited average transmit power. The proposed detector achieves substantial performance gain for higher‐order systems attaining a near optimal BER performance with reduced computational complexity as compared with SD. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
69.
Intermetallic growth and ball shear behavior of annealed Cu wire bonds on Al have been studied. The shear strength of Cu ball
bonds decreased with time, and ductile fracture was the dominant failure mode from 125°C to 150°C. Al pad peel-off occurred
as the aging temperature was increased above 150°C. The overall Cu/Al intermetallic thickness exhibited parabolic behavior
as a function of time. A linear correlation was established between ball shear strength, metal peel-off occurrence, and intermetallic
growth. The Cu/Al intermetallic growth activation energy was 0.23 eV, and the intermetallics identified in the experiment
were CuAl2 and CuAl. 相似文献
70.
Martínez Viedma P Sobrino López A Ben Omar N Abriouel H Lucas López R Valdivia E Martín Belloso O Gálvez A 《International journal of food microbiology》2008,128(2):244-249
The effect of the broad spectrum cyclic antimicrobial peptide enterocin AS-48 combination with high-intensity pulsed-electric field (HIPEF) treatment (35 kV/cm, 150 Hz, 4 micros and bipolar mode) was tested on Salmonella enterica CECT 915 in apple juice. A response surface methodology was applied to study the bactericidal effects of the combined treatment. The process variables were AS-48 concentration, temperature, and HIPEF treatment time. While treatment with enterocin AS-48 alone up to 60 microg/ml had no effect on the viability of S. enterica in apple juice, an increased bactericidal activity was observed in combination with HIPEF treatments. Survival fraction was affected by treatment time, enterocin AS48 concentration and treatment temperature. The combination of 100 micros of HIPEF treatment, 30 microg/ml of AS-48, and temperature of 20 degrees C resulted in the lowest inactivation, with only a 1.2-log reduction. The maximum inactivation of 4.5-log cycles was achieved with HIPEF treatment for 1000 micros in combination with 60 microg/ml of AS-48 and a treatment temperature of 40 degrees C. Synergism between enterocin AS-48 and HIPEF treatment depended on the sequence order application, since it was observed only when HIPEF was applied in the presence of previously-added bacteriocin. The combined treatment could improve the safety of freshly-made apple juice against S. enterica transmission. 相似文献