Molecular motifs for additives that retard PEO crystallization

We investigate the influence of several bifunctional phenol additives (resorcinol: RES, hydroquinone: HYD, p‐hydroxybenzoic acid: PHBA, and p‐nitrophenol: PNP) on the crystallization of matrix polymer, polyethyleneoxide. We employ solid state Nuclear Magnetic Resonance spectroscopy (NMR), Differential Scanning Calorimetry (DSC), optical microscopy, and Small Angle X‐ray Scattering (SAXS) to investigate crystallization of the additivated PEO and compare with Density Functional Theory (DFT) calculations of additive‐PEO interactions. Additive‐polymer interactions are a function of the functional groups on the additive. Temperature‐dependent spherulitic growth rate measurements from optical microscopy and SAXS lamellar long spacings indicate a distinct trend in the effect of additives on PEO crystallization. Change in PEO crystallization is most pronounced with PNP, followed by PHBA and finally RES and HYD. This trend correlates qualitatively with the binding energies of additive‐PEO interactions from DFT studies. Our results suggest that DFT calculations might be a useful screening tool to evaluate the influence of additives on polymer crystallization. POLYM. ENG. SCI., 57:857–864, 2017. © 2016 Society of Plastics Engineers     

Transport of aromatic solvents through nitrile rubber/epoxidized natural rubber blend membranes

The sorption and diffusion behavior of a series of aromatic solvents through blends of nitrile rubber (NBR) and epoxidized natural rubber (ENR) have been studied in the temperature range of 28–70°C. The effect of blend ratio, penetrant size and temperature on the transport properties was investigated. The relationship between the diffusion behavior and the morphology of the system was examined. Different transport parameters such as diffusion coefficient, permeability coefficient and swelling ratio have been calculated. Experimental permeability coefficients were compared with various theoretical models. The van't Hoff relation was used to compute the thermodynamic parameters.     

Effect of full and partial-bed configuration on carbon removal performance of biological aerated filters

A comparative study to explore the characteristics of partially and fully packed biological aerated filters (BAFs) in the removal of carbon pollutant, reveals that the partial-bed reactor can perform comparably well with the full-bed reactor. The organic removal rate was 5.34 kg COD m(-3) d(-1) at Organic Loading Rates (OLR) 5.80+/-0.31 kg COD m(-3) d(-1) for the full-bed, and 5.22 kg COD m(-3) d(-1) at OLR 5.79+/-0.29 kg COD m(-3) d(-1) for the partial-bed. In the partial-bed system, where the masses of biomass were only 41-51% of those of the full-bed, the maximum carbon removal limit was still between 5 to 6 kg COD m(-3) d(-1). At organic loadings above 5.0 kg COD m(-3) d(-1), the carbon removal capacity in both systems was limited by the mass and activity of microorganisms. The SRT in the full and partial-bed reactors was primarily controlled by the biomass loss in the effluent and during backwash operation. The SRT was reduced from 20.08 days at OLR 4.18+/-0.20 kg COD m(-3) d(-1) to 7.62 days at OLR 5.80+/-0.31 kg COD m(-3) d(-1) in the full-bed, and from 7.17 days to 4.21 days in the partial-bed. After all, SRT values in the partial-bed were always lower than those in the full-bed.     

Preparation and mechanical properties of crosslinked 1,2,3‐triazole‐polymers as potential propellant binders

Thirteen triazole polymers were prepared as potential rocket propellant binders by the reactions of various diacetylenes and diazides. The reaction of E300 dipropiolate ( 1 ) with diazide ( 2 ) obtained from tetraethylene glycol was selected to study the effects of concentration of the tetraacetylene functionalized crosslinker ( 3 ) on the mechanical properties of resulting triazole polymers. The modulus of the polymers increased, whereas the strain (% elongation at failure) decreased with increasing percentage of crosslinker. The resulting triazole polymers also showed that the desired mechanical properties could be obtained by adjusting the crosslinker concentration during the polymerization. Addition of 43 wt % aluminum filler did not significantly affect the strain. The modulus of these triazole polymers was comparable with typical polyurethane elastomeric matrices for rocket propellants. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

White-light interferometry with polarization phase-shifter at the input of the interferometer

Abstract

In white-light interferometry the surface profile is determined by measuring the fringe contrast function of the white-light interferogram. One of the techniques proposed for the measurement of the fringe contrast function is the use of the phase shifting technique with the help of an achromatic phaseshifter. The available phase-shifters employ a rotating polarization component at the output end of the interferometer. Using a rotating polarization component at the input end, rather than at the output end, has certain advantages. In this paper we investigate a rotating half-wave plate phase-shifter at the input end for its applications to a white-light interferometer.     

An efficient soft-computing technique for extraction of EEG signal from tainted EEG signal

Electroencephalography (EEG) is the recording of electrical activity of neurons within the brain and is used for the evaluation of brain disorders. But, EEG signals are contaminated with various artifacts which make interpretation of EEGs clinically difficult. In this research paper, we use a soft-computing technique called ANFIS (Adaptive Neuro-Fuzzy Inference System) for the removal of EOG artifact, combined EOG and EMG artifact. Improvement in the output signal to noise ratio and minimum mean square error are used as the performance measures. The outputs of the proposed technique are compared with the outputs of techniques such as neural network, based on ADALINE (Adaptive Linear Neuron) and adaptive filtering method, which makes use of RLS (Recursive Least Squares) algorithm through wavelet transform (RLS-Wavelet). The obtained results show that the proposed method could significantly detect and suppress the artifacts.     

Skin detection by dual maximization of detectors agreement for video monitoring

This paper presents an approach for skin detection which is able to adapt its parameters to image data captured from video monitoring tasks with a medium field of view. It is composed of two detectors designed to get high and low probable skin pixels (respectively, regions and isolated pixels). Each one is based on thresholding two color channels, which are dynamically selected. Adaptation is based on the agreement maximization framework, whose aim is to find the configuration with the highest similarity between the channel results. Moreover, we improve such framework by learning how detector parameters are related and proposing an agreement function to consider expected skin properties. Finally, both detectors are combined by morphological reconstruction filtering to keep the skin regions whilst removing wrongly detected regions. The proposed approach is evaluated on heterogeneous human activity recognition datasets outperforming the most relevant state-of-the-art approaches.     

Cuckoo search (CS)-NFC-based UPQC for compensating voltage sag of nonlinear load

In this paper, a cuckoo search (CS) algorithm-based neuro-fuzzy controller (NFC) is developed to improve the performance of unified power quality conditioner (UPQC). The CS algorithm is used for optimising the output of neural network (NN) so that the classification output of the NN is enhanced. The inputs of the networks are error and change of error voltage of the PQ issue signal of nonlinear load which are calculated by comparison with the reference signal. Next, the output of network, i.e. regulated (compensated) voltage, is optimised by the CS algorithm. From the output of CS, an optimum rule-based fuzzy interference system is developed and the PQ problem is compensated. The CS-NFC-based UPQC is implemented in MATLAB/Simulink and the PQ issue clearing performance is analysed. The PQ issue clearing performance of proposed UPQC is compared with traditional UPQC, NFC-UPQC, GA-NFC-UPQC and adaptive GA-NFC-UPQC. The CS-NFC-based UPQC controller has lesser error deviation of 2.8% with traditional UPQC, 2.12% with NFC, 1.7% with GA-NFC and 0.6% with adaptive GA-NFC.     

P — A logic — a compositional proof system for distributed programs

Summary This paper describes a compositional proof system called P-A logic for establishing weak total correctness and weak divergence correctness of CSP-like distributed programs with synchronous and asynchronous communication. Each process in a network is specified using logical assertions in terms of a presuppositionPre and an affirmationAff as a triple {Pre}S{Aff}. For purely sequential programs, these triples reduce to the familiar Hoare triples. In distributed programs, P-A triples allow the behaviour of a process to be specified in the context of assumptions about its communications with the other processes in the network. Safety properties of process communications, and progress properties such as finiteness and freedom from divergence can be proved. An extension of P-A logic allowing proof of deadlock freedom is outlined. Finally, proof rules for deriving some liveness properties of a program from its P-A logic specification are discussed; these properties have the form Q untilR, whereQ, R are assertions over communication traces. Other liveness properties may be derived from these properties using the rules of temporal logic. Paritosh Kulin Pandya received his Master's degree in Computer Science from the Indian Institute of Technology, Kanpur in 1982, and a Ph.D. from the Tata Institute of Fundamental Research in 1988 where he is currently employed. He has worked as a Research Officer in the Programming Research Group of the Oxford University from 1988 to 1991. Mathai Joseph has since 1985 been professor of Computer Science at the University of Warwick where he leads a group working on developing formal techniques for specifying and implementing realtime and fault-tolerant systems.Supported in part by Visiting Fellowships awarded by the Science and Engineering Research Council (research grant GR/D 90918) and the British Council