Measurement of permittivity and dielectric loss in 2,4-dimethyl substituted pyridine using microwave cavity spectrometer and time domain reflectometer

Microwave cavity spectrometer and time domain reflectometer is used to measure the permittivity and dielectric loss at different temperatures in 2,4-dimethyl substituted pyridine. The observed data of the width of resonance profile and the shift in the resonance frequency have been analyzed using Slater perturbation equations for cavity spectrometer. The dielectric parameters measured from the time domain reflectometer as a function of time at different temperatures have been transformed to frequency domain to obtain the permittivity and dielectric loss. The observed values of the permittivity and dielectric loss at 9.0 GHz are fitted in Slater's perturbation equations to obtain the form factor, which represents interactions. The relaxation time has been evaluated at different temperatures using the ratio of width and twice of frequency shift and thermodynamical parameters have been determined. This experimental study provides fruitful information about the bulk properties of 2,4-dimethyl substituted pyridine.     

Generalized features for electrocorticographic BCIs

This paper studies classifiability of electrocorticographic signals (ECoG) for use in a human brain-computer interface (BCI). The results show that certain spectral features can be reliably used across several subjects to accurately classify different types of movements. Sparse and nonsparse versions of the support vector machine and regularized linear discriminant analysis linear classifiers are assessed and contrasted for the classification problem. In conjunction with a careful choice of features, the classification process automatically and consistently identifies neurophysiological areas known to be involved in the movements. An average two-class classification accuracy of 95% for real movement and around 80% for imagined movement is shown. The high accuracy and generalizability of these results, obtained with as few as 30 data samples per class, support the use of classification methods for ECoG-based BCIs.     

Analysis of FRFT Based MMSE Receiver for MIMO Systems

In this paper, fractional Fourier transform based minimum mean squared error (MMSE) receiver is analyzed and compared with the time and frequency domain MMSE receivers in a multi-antenna environment. The distribution of SINR at the output of the receiver is used for calculating the bit error probability and the results are verified by comparison with the results obtained by Monte Carlo simulations.     

Fuzzy Logic Based Multi-criteria Intelligent Forward Routing in VANET

Wireless Personal Communications - Vehicular ad-hoc network have the capability for enhancing the road safety using intelligent transportation system by communicating with each other (V–V) as...     

Solutions to a class of linear-quadratic-Gaussian (LQG) stochastic team problems with nonclassical information

We consider a stochastic dynamic team problem with two controllers and nonclassical information, which can be viewed as the transmission of a garbled version of a Gaussian message over a number of noisy channels under a fidelity criterion. We show that the optimum solution (under a quadratic loss functional) consists of linearly transforming the garbled message to a certain (optimum) power level P^* and then optimally decoding it by using a linear transformation at the receiving end. The power level P^* is determined by the solution of a fifth order algebraic equation. The paper also discusses an extension of this result to the case when the channel noise is correlated with the input random variable, and shows that for the single channel case the optimum solution is again linear.     

A generalized fault simulator for combinational logic circuits

A generalized approach to the design of fault simulator using a library of simulation primitives is presented in this paper. A comprehensive set of simulation primitives has been developed using C programming language on the IBM PC. This library of simulation primitives has been used in realizing a fault simulator for automatic test pattern generation in combinational logic circuits. The fault simulator employs a combination of random pattern generation, concurrent fault simulation and the FAN algorithm for generating the complete set of test vectors to cover all the faults in the fault dictionary of the circuit under test. The library of simulation primitives is general enough to facilitate the development of fault simulators using any other test algorithms such as DALG or PODEM.     

Dynamically vulcanized blends of polypropylene and ethylene‐octene copolymer: Comparison of different peroxides on mechanical,thermal, and morphological characteristics

Thermoplastic vulcanizates (TPVs) are prepared by the dynamic vulcanization process, where crosslinking of an elastomer takes place during its melt mixing with a thermoplastic polymer under high shear. TPVs based on polypropylene (PP) with different grades of ethylene‐octene copolymers (EOC) were prepared with a coagent assisted peroxide crosslinking system. The effect of dynamic vulcanization and influence of various types and concentrations of peroxide were mainly studied on the basis of the mechanical, thermal, and morphological characteristics. Three structurally different peroxides, namely dicumyl peroxide (DCP), tert‐butyl cumyl peroxide (TBCP), and di‐tert‐butyl peroxy isopropyl benzene (DTBPIB) were investigated. The mechanical properties of the TPVs are primarily determined by the extent of crosslinking in the EOC and the degree of degradation in the PP phase. Among all peroxides used DCP gives best overall properties with low‐molecular‐weight EOC, whereas TBCP shows best property level with high‐molecular‐weight EOC‐based TPVs. These can be explained on the basis of the molecular characteristics of EOC and the nature of the peroxide used. Differential scanning calorimetery (DSC) and morphological analysis reveal that PP and EOC are a thermodynamically immiscible system. The melting endotherm was studied to determine the influence of various peroxides on crystallinity of the PP phase. Tensile fracture patterns were also analyzed to study the failure mechanism of the samples. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Fluidized bed film coating of cohesive Geldart group C powders

The difficulty of coating cohesive Geldart group C powders in a conventional fluidized bed is attributed to strong inter-particle force between fine particles leading to poor fluidization behavior. Dry coating approach involving deposition of nanosize particles on the surface of group C powders is considered to reduce the interparticle force and improve the fluidization behavior of fine powders. Polymer film coating at an individual particle level is achieved on these pre-coated fine powders in a commercially available spouting fluidized bed (MiniGlatt). The effect of operating conditions such as inlet air temperature, polymer concentration, polymer weight ratio, water percentage in solvent and spray rate of coating solution on the quality of film coating are investigated. Experimental results demonstrate that the quality of film coating goes down as polymer concentration in coating solution goes higher, whereas the lower inlet air temperature is found to enhance polymer film generation and coating quality. It is also observed that the higher polymer weight ratio promotes agglomeration without affecting the coating quality to a great extent. An optimum water ratio in acetone-water solvent as well as spray rate can be optimized to achieve superior coating quality with acceptable agglomeration ratio.Graphical abstractDry coating approach involving deposition of nanosize particles on the surface of group C powders is considered to reduce the interparticle force and improve the fluidization behavior of fine powders. Polymer film coating at an individual particle level is achieved on these pre-coated fine powders in a commercially available spouting fluidized bed (MiniGlatt). The effect of operating conditions such as inlet air temperature, polymer concentration, polymer weight ratio, water percentage in solvent and spray rate of coating solution on the quality of film coating are investigated. Experimental results demonstrate that the quality of film coating goes down as polymer concentration in coating solution goes higher, whereas the lower inlet air temperature is found to enhance polymer film generation and coating quality.

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Figure: SEM images of Aluminum-1 particles coated to investigate the effect of polymer concentration. (a, b) Spray rate 2.11 ml/min, polymer concentration 4%, inlet air temperature 40 °C, polymer weight ratio 4% and water in solvent 0%; (c, d) spray rate 2.11 ml/min, polymer concentration 16%, inlet air temperature 40 °C, polymer weight ratio 4% and water in solvent 0%.     

A Comparative Analysis of Acyl‐Homoserine Lactone Synthase Assays

Quorum sensing is cell‐to‐cell communication that allows bacteria to coordinate attacks on their hosts by inducing virulent gene expression, biofilm production, and other cellular functions, including antibiotic resistance. AHL synthase enzymes synthesize N‐acyl‐l ‐homoserine lactones, commonly referred to as autoinducers, to facilitate quorum sensing in Gram‐negative bacteria. Studying the synthases, however, has proven to be a difficult road. Two assays, including a radiolabeled assay and a colorimetric (DCPIP) assay are well‐documented in literature to study AHL synthases. In this paper, we describe additional methods that include an HPLC‐based, C?S bond cleavage and coupled assays to investigate this class of enzymes. In addition, we compare and contrast each assay for both acyl‐CoA‐ and acyl‐ACP‐utilizing synthases. The expanded toolkit described in this study should facilitate mechanistic studies on quorum sensing signal synthases and expedite discovery of antivirulent compounds.     

Microencapsulation of Cinnamon Oleoresin by Spray Drying Using Different Wall Materials

Microencapsulation of spice oleoresin is a proven technology to provide protection against degradation of sensitive components present therein. The present work reports on the microencapsulation of cinnamon oleoresin by spray drying using binary and ternary blends of gum arabic, maltodextrin, and modified starch as wall materials. The microcapsules were evaluated for the content and stability of volatiles, entrapped and total cinnamaldehyde content for six weeks. A 4:1:1 blend of gum arabic:maltodextrin:modified starch offered a protection, better than gum arabic as seen from the t_1/2; i.e., time required for a constituent to reduce to 50% of its initial value.