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in this paper, the problem studied is the sizing of a charging station for electric vehicles, i.e., the choice of the number and type of chargers to be installed in parking located in a smart building. In this context, based on the existing literature, the sizing problem has been formulated as a cost minimization problem considering the quality of service, i.e., minimizing the dissatisfaction rate. The optimization study simultaneously considers the overall investment cost function and the dissatisfaction rate as conflicting objective functions. Then, the proposed optimization model is analyzed and solved using genetic algorithms. These algorithms have provided qualified results that can be presented as solutions for investors in this field.

Reduced Beam Section (RBS) connections are a new type of connection which have been used in steel moment-resisting frames since the 1994 Northridge earthquake. This study is primarily aimed at analyzing the effects of suitable web stiffeners on preventing the deterioration effect of the hysteresis curve for RBS connections. Results of more than 183 nonlinear finite element analyses on different IPE sections with radius cut, straight cut, and drilled-flange RBS connection showed that different web stiffeners considerably contribute to the enhancement of seismic performance of RBS connections. In this research, the effects of factors such as the geometry and the number of the stiffeners, the distance between the stiffener and column side, and the length and thickness of the stiffener on the seismic performance of RBS connections were also studied.

This paper studies the thermal effect on dynamic stability of single-walled carbon nanotubes (SWCNTs) embedded in polymer matrix in low and high temperatures under impact loads. To this end, we present a nonlocal elastic shell model including thermal and small-size effects. Further, numerical calculations are presented for SWCNTs. Results show that the increasing in temperature field has the effect of increasing the dynamic buckling loads at low or room temperature. However, this effect leads to decrease the dynamic buckling loads at high temperature. In addition, it is observed that nonlocal dynamic buckling loads increase by an increase in the Neperian frequency.

Abstract: This work presents numerical simulation results for molten nickel and zirconia (YZS) droplets impacting on different microscale-patterned surfaces of silicon. The numerical simulation clearly showed the effect of surface roughness and solidification on the shape of the final splat, as well as the pore creation beneath the sprayed material. Simulations were performed using computational fluid dynamic software, SimDrop. The code uses a three-dimensional finite-difference algorithm solving the full Navier-Stokes equation, including heat transfer and phase change. A volume of fluid (VOF) tracking algorithm is used to track the droplet-free surface. Thermal contact resistance at the droplet-substrate interface is also included in the model. Specific attention is paid to the simulation of droplet impact under plasma spraying conditions. Droplet sizes ranged from 15 to 60 microns with initial velocities of 70-250 m/s. Substrate surfaces were patterned with regular arrays of cubes 1-3 μm high, spaced either 1 μm or 5 μm from each other. Different splat morphologies produced by simulations are compared with those obtained from the experiment conducted under the same impact and surface conditions.

A novel biopolymer‐based superabsorbent hydrogel was synthesized through chemical crosslinking by graft copolymerization of partially neutralized acrylic acid onto the hydrolyzed collagen, in the presence of a crosslinking agent and a free radical initiator. The Taguchi method, a robust experimental design, was employed for the optimization of the synthesis reaction based on the swelling capacity of the hydrogels. This method was applied for the experiments and standard L16 orthogonal array with three factors and four levels were chosen. The critical parameters that have been selected for this study are crosslinker (N,N′‐methylene bisacrylamide), initiator (potassium persulfate), and monomer (acrylic acid) concentration. From the analysis of variance of the test results, the most effective factor to control equilibrium swelling capacity was obtained and maximum water absorbency of the optimized final product was found to be 500 g/g. The surface morphology of the gel was examined using scanning electron microscopy. Furthermore, the sorption capacity of the hydrogel toward bivalent metal ions was evaluated. Therefore, the hydrogel may be considered as a candidate to develop as an efficient biopolymer‐based chelating hydrogel for water treatment. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4878–4885, 2006