IAM: an improved mapping on a 2-D network on chip to reduce communication cost and energy consumption

Photonic Network Communications - Based on the recent research, the communication cost has been the most important open issue in network on chip (NoC). In other words, the lower the communication...     

Computational Analysis of Injection-Velocity Effects on Dynamic Parameters of Unconfined Fuel-Vapor Clouds

A computational investigation is performed to study the effects of injection velocity on the main dynamic parameters of the fuel cloud released into the open atmosphere. The volume, shape, and growth rate of the cloud, turbulence intensity, as well as the distribution of fuel concentration, temperature gradient, and self-ignition induction time are the most important parameters determining the mode of combustion that propagates through the cloud. A modified KIVA-based program is employed to fulfill the calculations. Systems of equations are solved by a finite-volume method. The k-ɛ model and discrete droplet model are applied for modeling gas-phase turbulence and liquid spray, respectively. The fuel-injection velocity is shown to have a major effect on turbulence intensity and uniformity of the cloud. With increasing injection velocity, the detonable part of the cloud rotates sooner and faster, and there is less time for ignition. A comparison with experimental results is performed for validation. __________ Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 5, pp. 29–40, September–October, 2005.     

弯剪作用下螺栓角部连接的性能分析

研究了腹板角钢尺寸对双腹板顶底角钢的弯曲-转动性能影响。研究中采用了多个三维有限元模型,以其几何和材料特性作为影响参数。在这些模型中,所有的连接组件,如梁、柱、角钢及螺栓都采用实体单元建模。构件间的相互作用效应,如螺栓滑移和摩擦,采用表面接触算法建模。为更精确地评估连接件的性能,在栓杆上施加预拉力作为第一荷载。     

Microstructural evolution of a commercial ultrafine alumina powder densified by different methods

The densification and grain growth of bodies made from a commercial ultrafine alumina powder was investigated. The primary powder was initially subjected to dry (uniaxial cold pressing) and wet shaping (slip casting), followed by conventional (CS)-, two step (TSS)-, and microwave (MS) sintering to explore the effect of each series of treatments on the densification and microstructural evolution of the specimens. It was demonstrated that a uniform microstructure with higher density would be obtained using the wet shaping method. In addition, microwave sintering was found to be more effective into the densification of the specimens and in yielding a finer grain structure. It is believed that the high heating rate and effective particle packing are responsible for the improvements in these properties. On this basis, it was also demonstrated that the fracture toughness of the samples increased significantly through the application of microwave sintering.     

A comparison between microwave-assisted and thermally synthesized esterquat softeners used as textile softening agents

Triethanolamine-based esterquat softener was synthesized by two different methods, microwave irradiation and conventional thermal methods. FT-IR spectra and critical micelle concentration were employed to investigate chemical and physical properties of the synthesized softeners. Softening power, wettability, bending rigidity, yellowness, and anti-wrinkling properties of the synthesized softeners were also evaluated. It was found that microwave-synthesized softener posses better softening, wettability, and anti-wrinkling properties whilst shorter reaction time with higher yield, less cost, and higher purity of the synthesized product were the other advantages of this method over the conventional thermal method.     

RSM optimized self-cleaning nano-finishing on polyester/wool fabric pretreated with oxygen plasma

In this study, polyester/wool blended fabric was coated with titanium dioxide nanoparticles. To enhance the adsorption and loading of nanoparticles on wool and polyester fibers, the samples were pretreated by low-temperature oxygen plasma. Citric acid was used to fix the TiO₂ nanoparticles on the fibers. The self-cleaning property of the finished samples was tested under UV-A light. The effect of plasma treatment time besides the concentrations of TiO₂ nanoparticles and citric acid on the self-cleaning properties of the samples was analyzed and optimized using response surface methodology. The surface chemistry and morphology of the samples were studied using Attenuated total reflectance-fourier transform infrared spectorscopy (ATR-FTIR) and field emission scanning electron microscope, respectively. The results showed that plasma treatment has a great effect on the loading of the nanoparticles on the surface of the fibers and enhancing the self-cleaning properties of the finished samples. The plasma-treated samples showed better water absorbency, enhanced tensile strength and approximately the same handle compared to raw samples after coating with TiO₂ nanoparticles.     

Investigation of a flame holder geometry effect on flame structure in non-premixed combustion

In this paper the effect of flame holder geometry on flame structure is studied. The obtained numerical results using realizable k-? and β-PDF models show a good agreement with experimental data. The results show that increasing in flame holder length decreases flame length and increases flame temperature. Additionally, it is observed that flame lengths decrease by increasing in flame holder radius and increase for larger radii. Furthermore in various radii, the flame temperature is higher for smaller flame lengths. It was found that behavior of flame structure is mainly affected by the mass flow rate of hot gases that come near the reactant by the recirculation zone.     

Application of the adjoint multi-point and the robust optimization of shock control bump for transonic aerofoils and wings

A shock control bump (SCB) is a flow control method which uses a local small deformation in a flexible wing surface to considerably reduce the strength of shock waves and the resulting wave drag in transonic flows. Most of the reported research is devoted to optimization in a single flow condition. Here, both equally and variably weighted multi-point optimization and a robust adjoint optimization scheme are used to optimize the SCB. The numerical simulation of the turbulent viscous flow and a gradient-based adjoint algorithm are used to find the optimum location and shape of the SCB for two benchmark aerofoils. A multi-point optimization method under a constant-lift-coefficient constraint is implemented to find the optimum design of a two-dimensional (2D) SCB and it is observed that the general results are similar to other optimization algorithms. To show that these results are extendable to real three-dimensional (3D) cases, a 3D bump model with 11 parameters is introduced, and it is optimized using both single- and multi-point optimization procedures. Although the 3D flow structure involves much more complexity, the overall results are shown to be similar to the 2D case.     

Low-cost optical approach for noncontact predicting moisture content of apple slices during hot air drying

Absorption and scattering properties of product change as moisture content is reduced, but it has not been investigated how these changes are correlated. This study was aimed to measure and test the feasibility of using optical properties in predicting the moisture content of sliced apple samples during hot air drying. In this investigation, the noninvasive backscattering laser imaging technique at three wavelengths (650, 780, and 880?nm) and Farrell’s diffusion theory were used to determine absorption and reduced scattering coefficients. Artificial neural network model was applied to correlate the optical coefficients and moisture content of samples. The highest correlation between above-mentioned parameters was found at 780?nm. The best moisture content prediction result was obtained when absorption and reduced scattering coefficients were combined at three wavelengths with R_p?=?0.984. The results suggested that this method can be effectively used to predict the moisture content and control the drying process.     

Poly(N-isopropylacrylamide)-coated β-cyclodextrin–capped magnetic mesoporous silica nanoparticles exhibiting thermal and pH dual response for triggered anticancer drug delivery

In this research a novel controlled anticancer drug delivery system with dual pH and thermal responses was designed based on magnetic mesoporous silica nanoparticles that were anchored by β-cyclodextrin and coated by poly(N-isopropylacrylamide) (PNIPAM). Results demonstrated that the behavior of doxorubicin (anticancer drug) release depended on pH and temperature conditions. At endosomal pH (pH 5.5) the amount of drug release enhanced because the cap was removed from the pores. Furthermore, PNIPAM shell collapsed above the lower critical solution temperature and the releasing of drug increased. Thus, this nanocarrier would have the potential to be applied in the tumor therapy.