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71.
Michael Farnsworth Elhadj Benkhelifa Ashutosh Tiwari Meiling Zhu Mansour Moniri 《Memetic Computing》2011,3(3):175-197
The application of multi objective evolutionary algorithms (MOEA) in the design optimisation of microelectromechanical systems (MEMS) is of particular interest in this research. MOEA is a class of soft computing techniques of biologically inspired stochastic algorithms, which have proved to outperform their conventional counterparts in many design optimisation tasks. MEMS designers can utilise a variety of multi-disciplinary design tools that explore a complex design search space, however, still follow the traditional trial and error approaches. The paper proposes a novel framework, which couples both modelling and analysis tools to the most referenced MOEAs (NSGA-II and MOGA-II). The framework is validated and evaluated through a number of case studies of increasing complexity. The research presented in this paper unprecedentedly attempts to compare the performances of the mentioned algorithms in the application domain. The comparative study shows significant insights into the behaviour of both of the algorithms in the design optimisation of MEMS. The paper provides extended discussions and analysis of the results showing, overall, that MOGA-II outperforms NSGA-II, for the selected case studies. 相似文献
72.
H. M. M. Mansour Jannette W. Guirguis A. I. Abdelmageed S. A. Hager 《Annalen der Physik》1989,501(4):260-270
The purpose of the present work is to extend earlier nuclear matter calculations to study the properties of neutron matter. The binding energy per particle, symmetry energy, single particle potential, effective mass, and magnetic susceptibility are calculated using a modified Skyrme interaction. These are calculated as a function of the Fermi momentum kf in the range 0 < kf < 2 fm?1. Two sets of the interaction parameters are obtained by fitting the interaction parameters using the available information on neutron matter. Relativistic corrections to the order 1/c2 are also calculated. The relativistic corrections are very small and they increase as kf is increased. 相似文献
73.
Mohy S. Mansour Ayman M. Elbaz William L. Roberts Mohamed F. Zayed Mrinal Juddoo Bassem M. Akoush Alaa M. Khedr Hazem M. Al-Bulqini Assaad R. Masri 《Proceedings of the Combustion Institute》2021,38(2):2597-2606
Turbulent flames with compositionally inhomogeneous mixtures are common in many combustion systems. Turbulent jet flames with a circular nozzle burner were used earlier to study the impact of inhomogeneous mixtures, and these studies showed that the nozzle radius affects the flame stability. Accordingly, planar turbulent flames with inhomogeneous turbulent jet are created in a concentric flow slot burner (CFSB) to avoid this effect in the present study. The stability characteristics, the mixing field structure, and the flame front structure were measured, and the correlations between stability and the mixing field structure were investigated. The mixture fraction field was measured in non-reacting jets at the nozzle exit using highly resolved Rayleigh scattering technique, and the flame front was measured in some selected turbulent flames using high-speed Planar Laser-Induced Fluorescence (PLIF) of OH technique. The data show strong correlations between flame stability and the range of mixture fraction fluctuations. The flames are highly stabilized within a mixing field environment with the range of fluctuation in mixture fraction close to the range of the flammability limits. The mixing field structure is also illustrated and discussed using a mixing regime diagram and showed that the scatter of the data of the different cases is consistent with the classified mixing regimes. Lean flames are stabilized in the current slot burner. The flame front structure topology varies consistently from thin, small curvature at the low level of turbulence and higher equivalence ratio to more wrinkled, larger curvature, but a thicker structure at a higher level of turbulence and lower equivalence ratio. 相似文献
74.
Zahra Mohammadpour Zahra Sadat Hashemi Fatemeh Malekian Jebeli Sahel Ghasemzadeh Esfandyar Askari Mandana Akbary-Yekta Ramin Sarrami-Forooshani 《Particle & Particle Systems Characterization》2021,38(12):2100162
Iron oxychloride (FeOCl) is known for reactive oxygen species (ROS) generation through Fenton chemistry. The activity of FeOCl is preserved in the slightly acidic pH value of the tumor microenvironment (pH 6.5−6.9). Such property can be advantageous in biobased systems, where ROS generation can be modulated in slightly acidic conditions, which is characteristic of the solid tumor microenvironment. In the present study, BSA-stabilized FeOCl nanosheets (NSs) are synthesized and characterized by transmission electron microscope, Fourier transform infrared spectroscopy, zeta potential analysis, dynamic light scattering, and UV–vis spectroscopy. The morphology of the nanoparticles is flake-like, and their hydrodynamic diameter is around 200 nm. MTT, apoptosis assay, and trypan blue staining evaluate the toxicity of FeOCl NSs toward the 4T1 cell line. It is found that the toxicity of the NSs is higher in physiological conditions of solid tumors (pH 6.5, H2O2 100 × 10−6 m ) than in the conditions of healthy organs (pH 7.4). Specifically, cancer cells are in their late apoptotic stage by more than eight times higher at pH 6.5 than pH 7.4. The toxicity results are in agreement with the in vitro catalytic assay of the NSs. Therefore, the FeOCl NSs can be the building blocks for constructing chemodynamic therapy agents. 相似文献
75.
The energy spectra of three types of two-dimensional potentials(we will call them‘Davidson-like potentials’(DLPs)),characterized by four minima separated by barriers,are investigated.The predictions for spectra and wave functions are obtained by using the nine-point finite-difference method.For these potentials,with the existence of a single configuration,a transition of spectra,as a function of barrier height,is covered from tunneling splitting modes to fluctuations phenomena,with equal peaks wave functions,crossing to the spectra of purely anharmonic oscillator potentials(AOPs).A different type of phase transition occurs when two(or more)configurations coexist.With the change of the parameters,a transition of spectra is covered from coexistence phenomena of two distinct quantum tunneling modes to fluctuations phenomena,with unequal peaks wave functions,crossing to the spectra of purely AOPs.Using DLPs,a particular application of the coherent quadropole-octupole model to describe energy bands with alternating parity of the nuclei100Mo,146,148Nd,148,150Sm,220Ra,220,222Rn,and220,222Th is presented.The global parametrization of the model for the selected nuclei is achieved. 相似文献
76.
Marwa F. Mansour Ehab F. ElKady Nabawia M. El-Guindi Samir M. El-Moghazy Ann Van Schepdael 《Analytical letters》2017,50(11):1778-1802
Spectrophotometry was used with multivariate calibration to simultaneously determine compounds in mixtures. Two antidepressant mixtures were investigated: imipramine hydrochloride and chlordiazepoxide and nortriptyline hydrochloride and fluphenazine hydrochloride. Considerable spectral overlap and large differences in component concentrations were challenges. Since this type of analysis is often performed using complex algorithms, a simple strategy was used here for the simultaneous determination of both mixture components by classical least squares, principal component regression, and partial least squares. Experimental design was used to select the optimum parameters including the wavelength range, sampling interval, software, and derivative order. Accuracy was enhanced by proper wavelength selection. In addition, derivatives of the raw spectra improved the selectivity. The standard deviation, deviation of mean recovery from 100%, and prediction ability of the models were used as the responses. In respect to these terms, first-order derivatization of the spectra and a sampling interval of 1?nm provided the best results. In particular, the low concentration compounds in the mixtures (chlordiazepoxide and fluphenazine) were determined more accurately with precision lower than 3%. The strategy was used for the quality control of pharmaceuticals containing the mixtures without chemical pretreatment. 相似文献
77.
A reversed-phase dispersive liquid-liquid microextraction (RP-DLLME) method was developed for the preconcentration and direct HPLC determination of oleuropein in olive's processing wastewater (OPW) and olive leaves extracts. In conventional DLLME, the sedimented phase is a micro-drop of a chlorinated organic solvent that is not compatible with RP-HPLC. Therefore, solvent evaporation and reconstitution with an appropriate solvent is often required. In RP-DLLME, this problem was overcome by overturning the solvent polarity in the ordinary DLLME and replacing the organic solvent with water. A central composite chemometrics design was used for multivariate optimization of the effects of five different parameters influencing the extraction efficiency of the method. In the optimized conditions, a mixture of 1.4 mL of an ethyl acetate extract of sample and 40 μL water (pH 5.0) was rapidly injected into 5.3 mL of cyclohexane. After centrifugation of the formed cloudy mixture, a micro-drop of the aqueous phase was sedimented at the conical bottom of the centrifuge tube. This phase, that contained the preconcentrated and partially purified analyte, was directly injected into an RP-HPLC column for analysis. A mean extraction recovery of 102.5 (±4.5) % with enrichment factors exceeding 38, was obtained for five replicated analysis. The detection limit of the method (3σ) for OE was 0.02 μg L−1 for OPW and 2 × 10−3 mg kg−1 for olive leaves samples. The results showed that, RP-DLLME is a promising technique which is quick, easily operated and can be directly coupled to HPLC. 相似文献
78.
79.
Johannes Hatzl Toufik Mansour Mark Shattuck 《Journal of Mathematical Modelling and Algorithms》2011,10(2):193-203
Consider the set S of points in the plane consisting of the ordered pairs (i, j ), where
1 \leqslant i \leqslant m1 \leqslant i \leqslant m and
1 \leqslant j \leqslant n1 \leqslant j \leqslant n. A problem related to the study of segmentation evaluation of visual images concerns finding a permutation σ of the points of S for which the sum
?s ? Sd(s, s(s)) \sum\limits_{s \in S}d(s, \sigma(s)) 相似文献
80.
Ebrahim Hashemi 《Mediterranean Journal of Mathematics》2011,8(2):207-214
Let R be a ring with unity and M be a right R-module. The system M[x] forms a left near R[x]-module under addition and substitution operations. In this paper we extend the study of annihilator conditions on nearring
of polynomials to left near R[x]-module M[x], when M is a reduced Baer module. Also, we give a characterization of reduced modules. As a corollary we obtain some results of Birkenmeier
and Huang [3]. 相似文献
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