A novel multilayer AAA model for integrated applications

Neural Computing and Applications - Nowadays, one of the problems in current authentication, authorization and accounting (AAA) model is lack of accurate roadmap of access management in integrated...     

Polystyrene-attached graphene nanolayers by reversible addition-fragmentation chain transfer polymerization: a grafting from epoxy groups with various densities

Graphene oxide was chemically functionalized with a modifier synthesized from coupling reaction of ethylenediamine and 2-(dodecylthiocarbonothioylthio)-2-methylpropionic acid in low and high graft densities. Then, the modified graphenes were used in grafting from reversible addition-fragmentation chain transfer polymerization of styrene. Successful synthesis and grafting of modifier was approved by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy (FTIR). Also, FTIR, X-ray photo electron spectroscopy, and Raman spectroscopy were used to confirm the successful grafting of modifier moieties. Molecular weight and polydispersity index of attached polystyrene chains were studied by size exclusion chromatography. Thermogravimetric analysis was used to investigate the degradation temperatures, char contents, and graft ratios. Weight ratio of modifier in modified graphenes is calculated to be 4.93 × 10^?2 and 12.23 × 10^?2 for low and high graft densities. Also, molar ratio of modifier is 121.22 and 300.71 μmol/g respectively. Scanning electron and transmission electron microscopies show that graphite layers with flat surface were wrinkled during the oxidation process and also polystyrene-grafted graphenes are observed as opaque layers.     

Sonification and interaction design in computer games for visually impaired individuals

Multimedia Tools and Applications - Video games are changing how we interact and communicate with each other. They can provide an authentic and collaborative platform for building new communities...     

Comprehensive numerical study of molecular diffusion effects and Eddy Dissipation Concept model in MILD combustion

Moderate or Intense Low-oxygen Dilution (MILD) combustion is a clean combustion technology with high thermal efficiency and low levels of emissions. In this paper, by employing Adelaide Jet-in-Hot-Co-flow (AJHC), several approaches are examined to increase the numerical solution accuracy. First, molecular diffusion effects are investigated in MILD combustion. Second, adjusting the Eddy Dissipation Concept (EDC) coefficients is comprehensively discussed, and finally, the reaction fraction coefficient and EDC formulation are investigated. The results show that the effect of enthalpy transport caused by molecular diffusion on the energy equation must be considered in the low oxygen concentration regions. Also, the maximum temperature in the MILD region can be kept constant by adjusting EDC coefficients. Furthermore, it is shown that applying the reaction fraction factor increases the accuracy of the numerical solution in the MILD region.     

BLARK for multi-dialect languages: towards the Kurdish BLARK

In this paper we introduce the Kurdish BLARK (Basic Language Resource Kit). The original BLARK has not considered multi-dialect characteristics and generally has targeted reasonably well-resourced languages. To consider these two features, we extended BLARK and applied the proposed extension to Kurdish. Kurdish language not only faces a paucity in resources, but also embraces several dialects within a complex linguistic context. This paper presents the Kurdish BLARK and shows that from Natural language processing and computational linguistics perspectives the revised BLARK provides a more applicable view of languages with similar characteristics to Kurdish.     

Evolutionary boundary constraint handling scheme

The performance of an optimization tool is largely determined by the efficiency of the search algorithms used in the process as well as the proper handling of complex constraints. From the implementation point of view, an important part of task ensuring an efficient algorithm to work to its best capability is to handle the boundary constraints properly and effectively. As most studies in the literature have focused on the development of algorithms and performance evaluation and comparison of optimization algorithms, this crucial step has not been explored very well, and consequently only limited studies have been carried out in this field. This paper intends to propose a simple and yet efficient evolutionary scheme for handling boundary constraints. The simplicity of this approach means that the proposed scheme is very easy to implement and thus can be suitable for many applications. We demonstrate this approach with an efficient algorithm, differential evolution, and we also compare it with other boundary constraint handling approaches for a wide set of benchmark problems. Based on statistical parameters and especially mean values, the results obtained by the evolutionary scheme are better than the best known solutions obtained by the existing methods.     

The effect of promoters on the CO<Subscript>2</Subscript> reforming activity and coke formation of nanocrystalline Ni/Al<Subscript>2</Subscript>O<Subscript>3</Subscript> catalysts prepared by microemulsion method

Mesoporous nanocrystalline nickel-alumina promoted catalysts with high surface area were prepared by microemulsion (ME) method and employed in dry reforming of methane reaction. The catalysts were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller surface area analysis (BET), temperature programmed reduction (TPR) and temperature programmed oxidation (TPO) techniques. The results showed that the prepared catalysts had high porosity with great surface area and small crystallite size. Among the K₂O, MgO, CaO and BaO promoters, the MgO promoter showed considerable effect on catalytic performance and coke suppression of catalyst.     

Amide–acid functional SiO2 nanocomposites based on new semi‐crystalline poly(ether‐sulfone‐amide): thermal,combustion and mechanical studies

New amide–acid functional SiO₂ nanoparticle (FSNP)‐reinforced semi‐crystalline aliphatic–aromatic poly(ether‐sulfone‐amide) (PESA) was synthesized using a solution method in dimethylformamide. The surfaces of SiO₂ nanoparticles were functionalized with phthalic anhydride, and subsequently PESA was synthesized using direct polymerization with good yield and desired molar mass. PESA / SiO₂ nanocomposites (PSNCs) were prepared with three different contents of FSNP and the morphology and mechanical, thermal and combustion properties of the PSNCs were studied. The results of X‐ray diffraction, field‐emission scanning electron microscopy and transmission electron microscopy showed a uniform dispersion for FSNP in the PESA matrix. According to the results of mechanical tests, the tensile strength and the Young's modulus of PESA were enhanced by FSNP loading. Thermogravimetric analysis and derivative thermogravimetry results showed a substantial improvement in thermal properties of PESA. The temperature at 5% mass loss was increased from 371.7 to 395.8 °C for the PSNC containing 8 mass% of FSNP, as well as the char yield being enhanced greatly, which was about 30% higher than that of neat PESA. Significant improvements in combustion properties were observed for PSNCs from microscale combustion calorimetry. The peak heat release rate showed an obvious improvement and decreased by about 57% compared to that of neat PESA on 8 mass% loading of FSNP. © 2016 Society of Chemical Industry     

Highly efficient synthesis of benzopyranopyridines via ZrP2O7 nanoparticles catalyzed multicomponent reactions of salicylaldehydes with malononitrile and thiols

ZrP₂O₇ nanoparticles as an efficient catalyst have been used for the preparation of benzopyrano[2,3-b]pyridines from the four-component condensation reaction of salicylalde-hydes, thiols, and 2 equiv. of malononitrile under reflux conditions in ethanol in excellent yields and short reaction times.     

Voice controlled wheelchairs: Fine control by humming

People without disabilities seamlessly control devices with their hands. Interestingly, their hands can perform coarse and fine control. Implementing smooth control for computerized systems is not straightforward and most of the time it is not intuitive either. Here we offer a solution to that problem: smooth control through humming. Voice commands have become ubiquitous in modern technology. Speech-to-text applications abound. Smooth control, on the other hand, has not been tackled yet. Here we design and implement a humming control technique, and demonstrate a hardware implementation with a powered wheelchair. Once actuated, the speed with which the chair moves will depend on the subtle variation on the fundamental frequency of the user's humming, acquired through an accelerometer measuring vocal cord vibration. We also discuss two signal processing techniques that handle commonly encountered issues when trying to resolve frequencies in real time data. The hardware implementation shows performance of 80% and higher in speech recognition for signal-to-noise ratio (SNR) higher than 8 dB and 100% in smooth control and frequency detection for all tested SNRs. We also discuss potential applications of smooth humming control to other assistive technology.