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We report on the processing and characterization of high performance epitaxial manganite films grown on SrTiO3 and SrTiO3 buffered MgO substrates with a Tc tailored to room temperature. We have demonstrated that La1-xBaxMnO3 and La1-xSrxMnO3 epitaxial films on SrTiO3 buffered MgO substrate show significantly improved transport and magnetization properties in the vicinity of room temperature on ex situ annealing at 900 °C. Our results suggest that manganite films can be grown on either SrTiO3 or SrTiO3 buffered MgO substrates which can serve as template layer to integrate manganites onto appropriate semiconductors for device applications. [ABSTRACT FROM AUTHOR]

Spar Wingskin Joint (SWJ) comprises of a thin spar which overlaps and is co-cured to a thick wingskin by suitable adhesive materials. These joints are mostly used in integral modular fabrication of aircraft and fuselage wing structures usually made with curved laminated Fibre Reinforced Polymeric (FRP) composite panels. This paper deals with the analyses of initiation of adhesion failure and its propagation in SWJs subjected to transverse loadings using Finite Element Analyses (FEA) and fracture mechanics approach. Normal and shear stress distributions at different interfacial locations between the adherends and the adhesive have been evaluated. Tsai-Wu coupled stress failure criteria have been used to identify the location of onset of adhesion failure. The critical location for onset of adhesion failure has been found to be at the toe-end of the spar wingskin overlap region. Pre-embedded adhesion failure has been simulated at this location and Strain Energy Release Rate (SERR) components corresponding to Mode I, Mode II and Mode III of adhesion failure have been determined using the principle of Virtual Crack Closure Technique (VCCT). Rate of propagation of adhesion failure has been evaluated by sequential release of Multi-Point Constraint (MPC) and contact finite elements provided at the pre-embedded failure front. It has been observed that Mode I component of SERR primarily governs the process of adhesion failure propagation. The appropriate spar overlap length on the wingskin has been determined in order to prevent adhesion failure. Further, an attempt has been made to improve the structural integrity of the SWJ by reducing the stress concentration at the ends of spar and wingskin overlap. This has been achieved by obtaining a favourable stress distribution over the entire joint structure by using Functionally Graded Materials (FGM) in the spar and wingskin adherend instead of FRP composite panels. Exponential gradation indices have been used for material grading of the spar and wingskin adherends. It has been seen that peel and shear stresses and values of SERR components as well as total SERR reduce significantly by use of FGMs with suitable exponential material grading index. [ABSTRACT FROM AUTHOR]

The effect of Mo doping on the structural and dielectric properties has been investigated in detail for Co-Zn spinel ferrite. Solid state reaction technique has been used to prepare the CZMO. The structural analysis is performed using HRXRD technique which confirms the inverse spinel structure of the material. The frequency and temperature dependence of dielectric constant are studied which reveals that the dielectric dispersion is due to Maxwell-Wagner type polarization in agreement with Koop's phenomenological theory. The contribution of grain and grain boundary at high and low frequency respectively are evident in the dielectric constant. The variation of dielectric loss tangent with both the temperature and frequency has been studied. The room temperature and high frequency dielectric loss is observed to be very small. Also it is revealed that the dielectric loss tangent decreases with Mo substitution. [ABSTRACT FROM AUTHOR]

3D Finite Element Analyses have been carried out for Spar Wingskin Joints made with laminated Graphite Fibre Reinforced Plastic composites subjected to uniformly distributed transverse load. The delamination has been pre-embedded at the most likely location, i.e. in resin layer between the top and next ply of the fibre reinforced plastic laminated wingskin and near the spar overlap end. Multi-Point Constraint finite elements have been made use of at the vicinity of the delamination fronts. This helps in simulating the growth of the embedded delamination at both ends. The inter-laminar peel and shear stresses responsible for causing delamination damage have been evaluated. Strain energy release rate components corresponding to the Mode I (opening), Mode II (sliding) and Mode III (tearing) of delamination are determined using the principle of Virtual Crack Closure Technique. These are seen to be different and non-self-similar at the two fronts of the embedded delamination. Mode I Strain energy release rate ( G I ) primarily governs the process of delamination propagation. [ABSTRACT FROM AUTHOR]

Abstract: Using glance-monitoring technologies for on-road studies is an excellent way to investigate driver behaviors in an ecologically valid setting. Recent advances in glance-monitoring technologies have made it possible to conduct on-road studies of drivers’ glance behavior that heretofore were simply not possible. Yet it is not always easy to determine which glance-monitoring technology to use for a particular application. Here, we first identify the generic capabilities of the various glance-monitoring technologies. We then describe how particular glance-monitoring technologies have been used in the field to (a) identify the skill deficiencies of novice and older drivers, (b) evaluate the effectiveness of training programs that are designed to reduce deficits in these skills, and (c) address interface issues both inside (e.g., collision warning systems) and outside (e.g., yield markings) the vehicle. The limitations and advantages of on-road eye-tracking and the associated glance-monitoring technologies are identified throughout. A comparison, where possible, is made between the results of on-road eye-tracking studies of drivers’ behaviors and the results of those studies conducted in the laboratory. Overall, the use of appropriate on-road glance-monitoring technologies has greatly enhanced our theoretical understanding of why drivers behave the way they do, and this knowledge has paved the way for significant improvements in road user safety. [Copyright &y& Elsevier]

This paper deals with the evaluation of inter-laminar stresses in the adhesive layer existing between the lap and the strap adherends of lap shear joints (LSJ) made with curved lami-nated fibre reinforced plastic (FRP) composite panels for varied embedded delaminations between the first and second plies of the strap adherend. Non-linear finite element analyses have been carried out using contact and multi point constraint (MPC) elements. The use of contact elements ensures avoidance of inter-penetration of delaminated surfaces. Sequential release of MPC elements facilitates computation of individual modes of Strain Energy Release Rates (SERR). The effects of varied delamination lengths on variations of peel and inter-laminar shear stresses and different modes of SERR are seen to be very significant. Their variations on both the delamination fronts, for each size of the delamination, are found to be much different from each other indicating different propagation rates at the two delamination fronts. The structural integrity of the LSJ in the presence of delamina-tions, thus, can be predicted with adaptive finite element (FE) simulations. It is further seen that the peak stress magnitudes and SERRs are higher in the LSJs made with curved FRP composite panels as compared to the flat laminates. This may be due to the stiffening effects induced by the curvature geometry of the curved composite panels. [ABSTRACT FROM AUTHOR]

Abstract: In-vehicle music retrieval systems are becoming more and more popular. Previous studies have shown that they pose a real hazard to drivers when the interface is a tactile one which requires multiple entries and a combination of manual control and visual feedback. Voice interfaces exist as an alternative. Such interfaces can require either multiple or single conversational turns. In this study, each of 17 participants between the ages of 18 and 30 years old was asked to use three different music retrieval systems (one with a multiple entry touch interface, the iPod™, one with a multiple turn voice interface, interface B, and one with a single turn voice interface, interface C) while driving through a virtual world. Measures of secondary task performance, eye behavior, vehicle control, and workload were recorded. When compared with the touch interface, the voice interfaces reduced the total time drivers spent with their eyes off the forward roadway, especially in prolonged glances, as well as both the total number of glances away from the forward roadway and the perceived workload. Furthermore, when compared with driving without a secondary task, both voice interfaces did not significantly impact hazard anticipation, the frequency of long glances away from the forward roadway, or vehicle control. The multiple turn voice interface (B) significantly increased both the time it took drivers to complete the task and the workload. The implications for interface design and safety are discussed. [Copyright &y& Elsevier]

Abstract: This paper deals with the analysis of active constrained layer damping (ACLD) of laminated cylindrical composite shells using vertically and obliquely reinforced 1–3 piezoelectric composite materials as the material of the constraining layer of the ACLD treatment. A finite element model has been developed for analyzing the ACLD of laminated symmetric and antisymmetric cross-ply and angle-ply composite shells integrated with the patches of such ACLD treatment. Both in-plane and out-of-plane actuation of the constraining layer of the ACLD treatment has been utilized for deriving the finite element model. The analysis revealed that the vertical actuation dominates over the in-plane actuation. Particular emphasis has been placed on investigating the performance of the patches when the orientation angle of the piezoelectric fibers of the constraining layer is varied in the two mutually orthogonal vertical planes. The analysis revealed that the vertically reinforced 1–3 piezoelectric composites which are in general being used for the distributed sensors can be potentially used for the distributed actuators of high-performance light-weight smart cylindrical shells. [Copyright &y& Elsevier]

This paper deals with the analysis of vertically reinforced 1-3 piezoelectric composite materials as the material for the distributed actuator of smart laminated composite plates. A simple micromechanics model has been derived to predict the effective elastic and piezoelectric coefficients of these piezoelectric composites which are useful for the three dimensional analysis of smart structures. The main concern of this study is to investigate the performance of a layer of this vertically reinforced 1-3 piezoelectric composite material as the constraining layer of the active constrained layer damping (ACLD) treatment. A finite element model has been developed for analyzing the active constrained layer damping of laminated symmetric and antisymmetric cross-ply and angle-ply composite plates integrated with the patches of such ACLD treatment. Both in-plane and out-of-plane actuation of the constraining layer of the ACLD treatment have been utilized for deriving the finite element model. The analysis revealed that the vertical actuation dominates over the in-plane actuation. Particular emphasis has been placed on investigating the performance of the patches when the orientation angle of the piezoelectric fibers of the constraining layer is varied in the two mutually orthogonal vertical planes. Also, the effect of different boundary conditions on the performance of the patches has been studied. The analysis revealed that the vertically reinforced 1-3 piezoelectric composites which are in general being used for the distributed sensors can be potentially used for the distributed actuators of high performance light-weight smart structures. [ABSTRACT FROM AUTHOR]

Abstract: The maximum efficiency of a transmission line is a concern from design and operation viewpoints. Today varieties of flexible AC transmission system (FACTS) devices are being included to enhance system stability and to improve power transfer capability. In this paper, the influence of different FACTS devices on maximum efficiency is studied. The equivalent A B C D constants of transmission system, which include different shunt and/or series FACTS devices at different locations of transmission line, are formulated to evaluate the maximum efficiency. Simulations on maximum transmission efficiency are performed for a 500kV system. [Copyright &y& Elsevier]

Abstract: We report on the observation of room-temperature ferromagnetism in epitaxial (Zn,Mn)O films grown by a pulsed-laser deposition technique using high-density targets. The X-ray, microscopic, spectroscopic and magnetic properties of target material containing 6at.% of Mn and films were compared. The target shows the presence of large clusters exhibiting paramagnetic behavior. However, ferromagnetic properties were observed in (Zn,Mn)O films grown at a substrate temperature of 500°C and with an oxygen partial pressure of 1mTorr. Although, crystalline quality of the film improves with increasing substrate temperature, the ferromagnetism becomes weaker. [Copyright &y& Elsevier]

We report on the synthesis of Nd:YAG nanoparticles by the coprecipitation technique and the optimum conditions for the processing of transparent ceramics. The powders prepared by the coprecipitation technique display significantly less agglomeration of crystallites, indicating higher sinterability. The crystallite size dependence on the calcinations temperature suggests the optimum temperature of 1100 °C, at which phase purity of the YAG nanopowder with the highest sinterability can be obtained. We have demonstrated that the optimum temperature for the vacuum-sintering is about 1785 °C for the uniaxially pressed samples to obtain transparent ceramic with uniform particle size of about 5–7 μm, and above this temperature, enormously large grain growth occurs, and facilitates large pores formation in the intergrain region that makes the ceramic fragile at the grain boundary. [Copyright &y& Elsevier]

Spline wavelet (SW) is an optimum wavelet among the various existing wavelets which possesses some superior properties like regularity, best approximation and compactness at a given order over other conventional bases. In this paper a novel integrated approach for power quality data compression using the SW transform (SWT) and neural network is presented and its performance is assessed in terms of compression ratio (CR), mean square error and percentage of energy retained in the reconstructed signals. Varieties of power quality events including voltage sag, swell, momentary interruption, harmonics, transient oscillation and voltage fluctuation are used to test the performance of the proposed approach. Computer simulation results indicate that the proposed scheme offers superior compression performance compared to the conventional discrete cosine transform (DCT) and the discrete wavelet transform (DWT)-based approaches. [Copyright &y& Elsevier]

We report on the fabrication of Ni/Al2O3/Si and textured Ni/Al2O3/Si3N4 multilayers containing Ni nanoparticles that exhibit significantly improved results. The secondary phases arising from thermal reaction between Ni and Si can be remarkably suppressed with increasing layers of Al2O3 and deposition of Ni/Al2O3 multilayers on Si3N4 substrates. Atomic force microscopy shows the formation of large as well as nanoclusters of Ni when grown on Si, whereas textured Ni nanoparticles are formed on Si3N4 substrates. The magnetization measurements on Ni/Al2O3/Si containing a single buffer layer of Al2O3 shows higher coercivity field with magnetic nanowire-like behavior, whereas with several Al2O3 alternate layers almost a superparamagnetic-like behavior is observed. However, significantly improved magnetic hysteresis was observed in textured Ni/Al2O3/Si3N4 multilayers due to preferred alignment of Ni nanocrystallites. [Copyright &y& Elsevier]

YBa2Cu3Oy samples with varying Y2BaCuO5 (211) second-phase concentrations have been prepared using the submicron-sized 211 precursors by a powder melting process method and their critical current density (Jc), flux pinning and microstructure have been investigated. The microstructural observations show that most 211 particles in the sample are submicron in diameter (as small as 300 nm), which can work as effective pinning centers. Jc in low fields increases monotonously with increasing the 211 concentration. A high irreversibility field above 7 T at 77 K in H∥c is observed in these samples. A very high Jc value of 1.6×105 A/cm2 at 77 K in self-field has been achieved in the sample with 25% 211 addition. A plateau-region of Jc versus field (as high as 60 000 A/cm2 at 77 K) is also obtained, which is very promising for applications. In addition, the scaling of pinning force as a function of the reduced field gives a peak position of 0.33 which is an indication of pinning provided by normal conducting 211 particles. [Copyright &y& Elsevier]

Radial basis function neural networks (RBFNN) and fuzzy neural networks (FNN) are finding increasing attention as AI techniques. Power systems protection is a complex task in which AI techniques are successfully employed. Minimal RBFNN (MRBFNN) is a newer version of neural network that provides a minimum number of neurons using the sequential learning and pruning strategy. On the other hand, the fuzzy neural network, using a pruning strategy, yields fewer fuzzy rules. These new techniques are employed for the protection of a power network having a thyristor-controlled series capacitor (TCSC) which introduces further complexity into the protection problem. A comparison of the two new schemes is also outlined. [ABSTRACT FROM AUTHOR]

A series of highly dense Ho-doped La0.67Ca0.33MnO3 (LCMO) bulk ceramic samples were processed in the temperature range 1450 to 1600 °C and performed transport measurement (temperature down to 5 K and magnetic field up to 7 T). The effect of sintering time and temperature on transport properties are reported here. The magnetization and resistance decreased as sintering temperature is increased. Surface structure and morphology were studied by XRD, SEM and TEM. XRD pattern showed the monophasic orthorhombic structure of the sample sintered within the above temperature range for a sintering period of 20 h. It is surprising and interesting to observe that at certain critical doping level transition temperature is increased significantly indicating its potential use in CMR-based device technology above room temperature. In this paper, we report that critical optimization of sintering parameter is very important to achieve enhanced transport and magnetic properties. [Copyright &y& Elsevier]

Magnetic properties of single crystalline and dense polycrystalline MgB2 prepared under high pressure have been investigated in a wide field range through local and global magnetization measurements using micro-Hall probe and SQUID magnetometer. The lower critical field, Hc1, measured by Hall probe shows a BCS-like temperature dependence and can be fitted by two-gap model. Field dependence of magnetic critical current density is quite different for single and polycrystalline samples. There is only one pinning force peak for bulk sample, whereas there are two pinning force peaks for single crystalline sample. The upper critical field, Hc2, and the irreversibility field, Hirr, have been measured with magnetic field parallel and perpendicular to the boron sheets and the anisotropy ratio of Hc2 is estimated to be about 3. [Copyright &y& Elsevier]

Magnetic properties of single crystalline and dense polycrystalline MgB2 prepared under high pressure have been investigated in a wide field range through local and global magnetization measurements using micro-Hall probe and SQUID magnetometer. The lower critical field, Hc1, measured by Hall probe shows a BCS-like temperature dependence and can be fitted by two-gap model. Field dependence of magnetic critical current density is quite different for single and polycrystalline samples. There is only one pinning force peak for bulk sample, whereas there are two pinning force peaks for single crystalline sample. The upper critical field, Hc2, and the irreversibility field, Hirr, have been measured with magnetic field parallel and perpendicular to the boron sheets and the anisotropy ratio of Hc2 is estimated to be about 3. [ABSTRACT FROM AUTHOR]

Studies flux pinning in melt-processed ternary (Nd-Eu-Gd) and Nd-based superconductors. Critical current density measurements; Transport properties; Partial vortex entanglement.

Studies the magnetization of NdBa[sub 2]Cu[sub 3]O[sub y] single superconducting crystals with various oxygen contents. Irreversibility field as a function of temperature; Reduced field dependence of critical current density; Normalized flux pinning force.

Presents an alternative approach for the protection of power transmission lines using a minimal radial basis function neural network (MRBFNN). Use of a sequential learning procedure to determine the optimum number of neurons in the hidden layer without resorting to trial and error; Adjustment of network parameters using a variant of extended Kalman filter.

Presents a novel fuzzy network approach for transmission system distance relaying scheme. Details on the neural network architecture; Application of pruning strategy for redundant fuzzification neurons elimination; Use of back propagation algorithm for the system training; Relevance of the method in power system fault determination.

Photoionization cross-sections and recombination rate coefficients are presented for the L-shell ground-state fine-structure levels 2s[sup 2]2p[sup 4] [sup 3]P[sub 2,0,1] of Fe xix. Several sets of calculations including relativistic effects are carried out: (i) Breit–Pauli R-matrix (BPRM), (ii) relativistic distorted-wave (RDW), and (iii) a semirelativistic calculation. Non-relativistic LS-coupling calculations are also performed for comparison. The BPRM calculations employ a configuration-interaction target representation for Fe xx consisting of 12 LS terms (23 fine-structure levels), as in the recently reported BPRM calculations by Donnelly et al. The background cross-sections in all three sets of present calculations agree with one another, but differ considerably from those of Donnelly et al. Owing to much more extensive resonance structures in the present BPRM calculations, the sum of the corresponding recombination rate coefficients for the [sup 3]P[sub 2,0,1] levels is up to 50 per cent higher than the LS rates at low temperatures but comparable for higher temperatures; this is in contrast to the results of Donnelly et al. who obtained the LS rates to be higher than their BPRM results by about a factor of 2. Reasons for these discrepancies are discussed. [ABSTRACT FROM AUTHOR]

Presents an apparent impedance calculation procedure for distance relaying of transmission line involving Flexible AC Transmission Systems devices, particularly the unified power flow controller (UPFC). Impact of the presence of the UPFC on the trip boundaries; Other factors influencing the trip boundary; Ideal trip characteristics.

Describes a method for estimating power system frequency in the presence of random noise and distortions using an extended complex Kalman filter. Development of a complex voltage vector using alpha-beta-transform; Computation of the true state of the model; Nonlinear filter; Results of computer simulation tests.

Studies the flux pinning behavior of ternary melt-processed (Nd-Eu-Gd)Ba[sub 2]Cu[sub 3]O[sub y] superconductors with varying defect concentrations using magnetotransport and magnetization measurements. Proof for the existence of additional pinning centers from a weaker superconducting phase.

A study was undertaken to investigate the rate of dissolution of the various Phosphorus (P) sources in an alluvial soil of Bihar under an incubation experiment in the laboratory for 35 days with 5 treatments viz., Control; RP (Rock Phosphate) @ 100% of the RDP (Recommended Dose of Phosphorus); 100% of RDF (Recommended Dose of Fertilizer NPK); REC (Rock phosphate Enriched Compost) @ 100% of the RDP and 50% RDP+REC @ 50% of the RDP. The P release pattern was determined for every treatment at a sampling interval of 7 days. The integrated treatment involving REC and P-fertilizer (50:50) performed better than other treatments. This combination released greater labile P (16.14 mgkg−1), Fe-Al-bound P (74.48 mgkg−1), and Ca bound P (147.04 mgkg−1) in soil. It could be concluded that enriched compost (50%) along with the reduced application (50%) of inorganic P fertilizer could be very helpful in supplementing the P requirement of plants by increasing its release and availability under naturally P deficient conditions. [ABSTRACT FROM AUTHOR]

Adhesive bonding techniques have increased its application in automobile industries. The most common bonded joint configuration is the lap-shear joint, which when subjected to loading shows a differential substrate straining at the overlap ends. One of the methods to improve its performance is by introducing a reverse bent angle to the adherends at the overlap area. In this paper, the parameters which affect the strength of the reverse bend joints are found out by conducting experiments on different specimens. A detailed study was carried out showing the trends in the joint performance by varying the input parameters. Preformed angle at the overlap area, overlap length, ultimate tensile strength and modulus of the substrates have shown significant effect on the improvement of strength. For most of the adherends used in the automotive industries it has been found that a 10 degree preformed reverse bend joint consistently showed a 15 percent improvement in the strength compared to the traditional lap-shear joint. A model was developed based on Artificial Neural Networking system identification methods to predict the optimum joint configuration based on the given input parameters. This can be used to design high-performance adhesive bonded joints for parts and assemblies in automotive and aerospace industries. [ABSTRACT FROM AUTHOR]

The optimization of high-quality melt-processed ternary (Nd-Eu-Gd)Ba[sub 2]Cu[sub 3]O[sub 7-δ] composite samples has been carried out to achieve the largest pinning. Our results suggest that the interaction between the twin planes and the fine second-phase precipitate forms a strongly pinned entangled vortex liquid in which vortices are correlated along the c axis. This pinned vortex liquid freezes into a glassy state at low temperature rendering high critical current density, J[sub c]. The maximum J[sub c] can be achieved in as-grown optimally annealed twinned sample with second phase precipitate without disturbing the twin influence. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have performed magnetic and transport measurements on La[sub 0.67]Ca[sub 0.33]MnO[sub 3] polycrystalline and partially melted samples. The magnetization and resistance decrease as sintering temperature is increased. The insulator-to-metal transition temperature is remarkably enhanced in the partially melted sample, enabling its possible applications at room temperature. The microscopic studies in melt samples show an excellent connectivity between grains, suggesting the enhancement of percolative transport by opening new conduction channels and the disappearance of magnetic phase boundary at elevated temperature by the ordering of Mn spins blocked at the grain boundary of sintered samples. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In the present study, numerical and experimental investigation of stress distribution pattern has been performed for thick walled nuclear rotor pipe joint of Alloy 617 and 10Cr steel. Hot wire Tungsten Inert Gas (HW-TIG) welding process has been adopted for multipass narrow groove welding since it yields better mechanical properties at low heat input than manual TIG welding and decreases the accumulation of residual stress significantly. The residual stress generated at the surface of the welded joint was evaluated experimentally using the Blind hole drilling technique (BHD), and consequently, the distribution of stresses along the thickness of the welded joint was masured using the Deep hole drilling (DHD) method. According to the findings, shrinkage at the HAZ area of the weld influences the stresses generated at the cylinder outer surface. The distribution of residual stresses in the weld region is driven mostly by the bending effect produced during the welding process. The influence of post weld heat treatment (PWHT) on residual stress distribution has also been investigated using both experimental and numerical approaches. Numerical investigations have been performed using ABAQUS finite element method. A 2D finite element model has been developed to simulate the welding process and the subsequent heat treatment, using coupled thermo-mechanical analysis. The residual stress results obtained from the numerical approach were validated with the experimentally obtained results and a good correlation has been found. The lumped pass model along with an equal density heat source has been implemented to minimize the computation complexity without affecting the accuracy of the simulated results. The obtained findings revealed that apart from weld centerline, hoop tensile residual stresses were higher around the buttered layer of Alloy 617 and 10Cr steel in an as-welded state. It has been found that nearly 80% of the stresses generated along the weld section have been released after PWHT. • Study of multi-pass dissimilar welded joint of rotor joint of Alloy 617 and 10Cr steel. • Experimental investigation of through thickness residual stresses in the DWJ using the deep hole drilling (DHD) method. • Evaluation of surface residual stresses using blind hole drilling (BHD) method. • Validation of experimental results using numerical analysis. [ABSTRACT FROM AUTHOR]

Abstract: Power system state estimation with exclusive utilization of synchronous phasor measurements demands that the system should be completely observable through PMUs only. To have minimum number of PMUs, the PMU placement issue in any network is an optimization problem. A three stage optimal PMU placement method is presented in this paper using network connectivity information. The method initially considers PMU in all buses of the network. Stage I and Stage II of the algorithm iteratively determine (i) less important bus locations from where PMUs are eliminated and (ii) strategically important bus locations where PMUs are retained. Stage III of the algorithm further minimizes the number of PMU using pruning operation. The set of PMUs obtained after Stage III is an optimal set of PMU locations for network observability. Proposed method is further extended for assuring complete observability under single PMU outage cases. Simulation results for IEEE 14-bus, 24-bus, 30-bus, 57-bus, 118-bus and New England 39-bus test systems are presented and compared with the existing techniques. Results show that the proposed method is simple to implement and accurate compared to other existing methods. [Copyright &y& Elsevier]

Abstract: Environmental contamination with Mycobacterium avium subsp. paratuberculosis (MAP) is thought to be one of the primary sources of infection for dairy cattle. The exact link between fecal shedding of MAP by individual cows and environmental contamination levels at the herd level was explored with a cross-sectional analysis of longitudinally collected samples on 3 dairy farms. Composite samples from multiple environmental sites in 3 commercial dairy herds in the Northeast US were cultured quarterly for MAP, providing 1131 samples (133 (11.8%) were culture-positive), and all adult animals in the herds were tested biannually by fecal culture (FC), for 6 years. Of the environmental sites sampled, manure storage areas and shared alleyways were most likely to be culture-positive. Environmental sample results were compared to FC results from either the concurrent or previous sampling date at both the herd and the pen level. At the herd level, a 1log unit increase in average fecal shedding increased the odds of a positive non-pen environmental sample by a factor of 6 and increased the average amount of MAP in non-pen samples by 2.9cfu/g. At the pen level, a 1log unit increase in average fecal shedding in the pen increased the odds of a positive environment by a factor of 2.4 and the average amount of MAP was increased by 3.5cfu/g. We were not able to model the relationship between non-pen environmental sample status and the distance between shedding animals and the sample''s location, and neighboring pens did not significantly affect the results of the pen-level analysis. The amount of MAP in pen-level samples and the probability of a pen testing positive for MAP were both positively but non-significantly correlated with the number of animals in the pen shedding >30cfu/g of MAP. At least 6 environmental samples met the criteria for the U.S. Voluntary Bovine Johne''s Disease Control Program on 47 of the 72 sampling dates; of these, 19 of the 47 FC-positive sampling dates were positive by the 6-sample environmental testing method, resulting in a herd sensitivity of 0.40 (95% CI: 0.26–0.54). None of the 3 FC-negative sampling dates produced positive environmental samples. Although environmental sampling can be used as a tool in understanding the level of MAP infection in a herd or pen, it did not appear to be a sensitive diagnostic method for herd positivity in these low prevalence herds, and its use may require caution. [Copyright &y& Elsevier]

Abstract: Magnetic nanoparticles of CoFe2O4 have been synthesized under an applied magnetic field through a co-precipitation method followed by thermal treatments at different temperatures, producing nanoparticles of varying size. The magnetic behavior of these nanoparticles was investigated. As-grown nanoparticles demonstrate superparamagnetism above the blocking temperature, which is dependent on the particle size. One of the nanoparticles demonstrated a constricted magnetic hysteresis loop with no or small coercivity and remanence at low magnetic field. However, the loop opens up at high magnetic field. This magnetic behavior is attributed to the preferred Co ions and vacancies arrangements when the CoFe2O4 nanoparticles were synthesized under an applied magnetic field. Furthermore, this magnetic property is strongly dependent on the high temperature heat treatments that produce Co ions and vacancies disorder. [Copyright &y& Elsevier]

Dissimilar metal welds (DMW) of ferritic to austenitic stainless steel are broadly used in steam generators working in power generation industries. Frequent failure of DMWs from the heat-affected zone (HAZ) of the ferritic part necessitates structural integrity assessment of the DMWs in order to determine and extend the lifetime of these components. In this regard, typical DMWs of SA516–309L–304L and SA516–309L/308L–304L attributed to domestic reactors were fabricated under different welding conditions. The effects of conventional and narrow weld groove configurations, buttering layer, and varying buttering layer width on the through-thickness residual stress fields in the DMWs were investigated experimentally and with the help of numerical simulations. Results show that the narrow groove weld is beneficial in reducing the residual stresses in the weld zone. Incorporating an additional buttering layer in the narrow groove joint further reduced the residual stresses across the weld joint. A 6 mm thick buttering layer was found to be competent enough to minimize the residual stresses dispersed across the weld cross-section. • Narrow weld groove exhibits reduction in residual stresses in weld zone. • Additional buttering layer reduced the level of residual stresses across the weld zone. • A 6 mm thick buttering layer was found to be competent enough. [ABSTRACT FROM AUTHOR]

Abstract: AgInSe2 (AIS) films were grown on n-type Si substrates by the ultra-high-vacuum pulsed laser deposition technique from the AIS target synthesized from high-purity materials. The X-ray diffraction and microscopic studies of the films show that films are textured having terrace-like surface morphology. The optical studies of the films show that the optical band gap is about 1.24 eV. The electrical conductivity of AgInSe2/Si films shows excellent diode characteristics. The photoconductivity of the AgInSe2/Si device shows photocurrent of 2.8 mA at a bias-voltage of −1 V with an open circuit voltage of 0.15 V. This shows that AIS films are very good absorber material for solar cell technology. [Copyright &y& Elsevier]

We report on the precise determination of the lower critical field (Hc1) of the newly discovered superconductor MgB2 measured by Hall probe. Two polycrystalline samples with different grain sizes and one single crystalline sample are compared. By setting a small criterion for the first flux penetration into the sample, Hc1 was determined. Based on our measurements, MgB2 seems more similar to borocarbides and low-Tc superconductors, which follow BCS temperature dependence, than to high-Tc superconductors. Comparison with two-gap superconductivity is also made. [Copyright &y& Elsevier]

Examines the use of slantlet transform in determining power quality (PQ) events. Filterbank approaches for the discrete wavelet transform; Occurrence of PQ disturbances; Impact of short circuit faults on voltage sags.

In this paper, frequency dependent dielectric parameters of pure oils and nanofluids have been studied at different temperatures to investigate any improvement of the dielectric properties due to the presence of nanoparticles. In power transformers, mineral oil is popularly used as an insulating material. However, mineral oils have inherent drawbacks associated with fire hazards and environmental issues. So, as an alternative, vegetable oils are drawing more attention of the researchers in this field. But, pure vegetable oil exhibits weak dielectric properties to be used under high electric stresses. Considering the drawbacks, extensive research work is going on to improve the dielectric strength of eco-friendly vegetable oils by using nanoparticles as additives. In this work, nanoparticles (TiO 2 and Al 2 O 3) based mineral and vegetable (FR3) oil samples have been prepared in laboratory for investigation of their dielectric properties for use in high voltage equipment through frequency domain spectroscopy. The dielectric dissipation factors obtained from FDS measurement have been compared for the aforesaid liquids. Furthermore, frequency domain spectroscopy has been conducted on pure oils and nanofluids at different temperatures to study the effect of temperature on their dielectric properties. Based on the experimental results, LFD of the insulation has been investigated to obtain an idea about aging status of it. • TiO 2 and Al 2 O 3 based nanofluids have been prepared in laboratory. • Temperature effects on Dielectric properties of Mineral and vegetable oil based nanofluids upto 90 °C. • Frequency Domain Spectroscopy has been conducted for different nanofluids at different temperatures. • Corelation between tanδ losses and low frequency dispersion (ΔC) has been proposed. [ABSTRACT FROM AUTHOR]

Abstract Ni-B coatings are promising materials for several applications in electronics, nuclear, automotive, aerospace, petrochemical and food industries owing to their exceptional mechanical and chemical properties such as, high hardness, high wear resistance and good corrosion resistance. However, the literature indicates that there is still significant scope for further improvement in properties of these coatings in order to improve their in-service performance and/or total service life. Considering this fact, a novel Ni-B-Tl 2 O 3 composite coatings has been developed via electrodeposition technique by reinforcing Tl 2 O 3 particles into the Ni-B matrix. The effect of addition of Tl 2 O 3 particles on the morphology, structure and electrochemical properties of Ni-B-Tl 2 O 3 coatings was investigated and compared with that of the Ni-B coatings. A substantial change on surface roughness, thermal properties, crystal structure, mechanical properties and corrosion resistance was observed due to the addition of Tl 2 O 3 particles to the Ni-B coatings. The as-deposited Ni-B coatings were found to be amorphous in nature, however the crystallinity of the composite coatings was significantly improved by the addition of the Tl 2 O 3 particles. Surface analyses showed an increase in surface roughness due to the addition of Tl 2 O 3 particles, which confirms the formation of fine and dense structures in both Ni-B and Ni-B- Tl 2 O 3 coatings. There is significant improvement in microhardness (by 80%) and elastic modulus (by 60%) of Ni-B-Tl2O 3 composite coatings as compared to Ni-B coatings mainly due to the addition of Tl 2 O 3 particles. Corrosion resistance was found to be improved significantly after the incorporation of Tl 2 O 3 into the Ni-B matrix which may be attributed to reduction in active area of Ni-B matrix. Highlights • Ni-B-Tl 2 O 3 composite coatings have successfully been electrodeposited. • Addition of Tl 2 O 3 has been observed to improve crystallinity of Ni-B coating. • Addition of Tl 2 O 3 has resulted in a significant change in surface morphology. • Ni-B-Tl 2 O 3 coating exhibited significant improvement in mechanical properties. • Ni-B-Tl 2 O 3 coating exhibited almost three times increase in corrosion resistance. [ABSTRACT FROM AUTHOR]

Toxoplasmosis is a worldwide zoonosis. The ingestion of uncooked/undercooked meat and consumption of water contaminated with Toxoplasma gondii oocysts excreted by felids are the main modes of transmission of this parasite. T. gondii has been reported in multiple cervid species; however, little is known of the parasite in North American elk ( Cervus canadensis ). In the present study, antibodies to T. gondii were detected in serum of wild elk from Pennsylvania collected during 2013–2016 by the modified agglutination test (MAT, cut-off 1:25); 221 of 317 (69.7%) had MAT titers of 1:25 in 19, 1:50 in 28, 1:100 in 34, and 1:200 or higher in 140. Thus most (44.1%) elk had relatively high titers. Seroprevalence was slightly higher in males (76.9%) than females (67.5%, not statistically significant, Chi-square tests, P < 0.0001) and was higher in adults (76.5%) than yearlings (46.4%, Odds ratio 3.82; 95% CL 1.72–8.47; P = 0.001) or calves (21.7%, Odds ratio 12.58; 95% CL 4.51–35.10; P < 0.0001). Annual seroprevalence was relatively stable throughout the period tested and ranged from 66.6% to 72.2%. Of the 101 elk harvested in 2016, hearts were bioassayed from 20 elk and tongues were bioassayed from 56; all tongue samples were negative. Viable T. gondii was isolated from hearts of two female elk, one of these was a seronegative adult and the other was a calf with no serum available for testing. Both T. gondii isolates were cultivated in cell culture and DNA derived from tachyzoites was characterized using the PCR-RFLP markers including SAG1, SAG2 (5′- 3′SAG2 and altSAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico. One isolate belongs to ToxoDB PCR-RFLP genotype #2 and the other is genotype #5. Both genotypes are frequently identified in animals in North America. [ABSTRACT FROM AUTHOR]

We have optimized Gd ion substitution in BiFeO 3 (BFO) and observed prominently change in structural, electrical and magnetic behavior of Bi 1+2x Gd 2x/2 Fe 1−2x O 3 ceramics synthesized through slow step sintering schedule. It is observed that with the increase in concentration of Gd (x=0.1), original structure of BFO is transformed from rhombohedral R 3 c space group to orthorhombic Pn 21 a space group. Surprisingly, unit cell volume is drastically contracted (35% for x=0.2) and the sintered specimen showed enhanced room temperature ferromagnetic behavior although the original BFO is normally G-type antiferromagnetic in nature at 643 K. It is expected that intrinsic chemical pressure within the bulk body built by the substitution of Gd in presence of excess bismuth greatly supported through unidirectional movement of electrical dipole moment with in each individual domain as a result of which suppression of leakage current with enhanced dielectric and ferroelectric hysteresis is observed. [ABSTRACT FROM AUTHOR]

• Tissue cyst formation in pork of 8 pigs was studied by mouse bioassay 7 and 14 days after infection with Toxoplasma gondii. • Bioassay of 5, 10, 50 g samples of meat revealed uneven distribution of tissue cysts. Among the meat sources of Toxoplasma gondii , pork is considered important in the epidemiology of toxoplasmosis in the USA. How soon after infection T. gondii forms tissue cysts in pork is unknown. In the present study, eight serologically negative ˜ 3 months old pigs were fed mouse tissues infected with VEG (Type III) strain of T. gondii and euthanized 7 (4 pigs) and 14 days (4 pigs) post-inoculation (p.i.). Meat from the right shoulder of each pig was bioassayed in mice for T. gondii tissue cysts by peptic digestion. From each pig, the shoulder muscle was cut at random spots into 5 g, 10 g and 50 g portions. Extreme care was taken to use different scalpels and forceps to minimize cross contamination among 17 samples (6 replicates of each 5 g and 10 g portions and 5 replicates of 50 g). From the four pigs euthanized at 7 days p.i., a composite of ˜ 200 g of leftover meat from each shoulder was bioassayed in cats and their feces were tested for oocyst excretion. All eight pigs developed T. gondii antibodies (modified agglutination test, MAT, 1: 80 or higher) and viable T. gondii was isolated from shoulder meat of each pig. All four cats fed pork from excreted T. gondii oocysts. The density of T. gondii , based on mouse infectivity, varied within 5–50 g samples each pig, and between pigs within the same group, day 7 versus day 14 p.i. There were no significant differences in mouse bioassay results obtained with day 7 versus day 14 infected pigs. Overall, the rate of isolation of T. gondii increased with sample size of meat bioassayed. Results demonstrate that tissue cysts are formed early in infection and they are unevenly distributed. [ABSTRACT FROM AUTHOR]

Cats are important in the epidemiology of toxoplasmosis because they are the only definitive hosts that excrete environmentally resistant Toxoplasma gondii oocysts. Little is known of feline toxoplasmosis in China and most of the literature is in Chinese. Here we summarized all published reports on feline toxoplasmosis in English and report first identification of oocyst excretion by naturally infected cats in China. Unfrozen tissues of 42 cats and feces of 360 cats from China were bioassayed in mice for isolation of T. gondii . Antibodies to T. gondii were found in 21 of 42 (50%) of cats by the modified agglutination test (cut-off 1:25). Viable T. gondii was isolated from tissues of eight of 21 seropositive but not from 21 seronegative (<1:25) cats. Viable T. gondii was isolated from feces of one cat. DNA derived from cell cultured tachyzoites of all nine T. gondii isolates was characterized by PCR–RFLP at 10 loci (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). Four genotypes were found; the genotypes of tissue isolates were ToxoDB #9 in six, ToxoDB #2 in one, and ToxoDB #17 in one. The fecal isolate was ToxoDB #1.To our knowledge, the present study is the first isolation of T. gondii from cat feces from China. [ABSTRACT FROM AUTHOR]

Highlights: [•] Regrowth of native oxides on GaAs surfaces was reduced by self-cleaning technique. [•] The thermal conversion of As–O into Ga–O reduction was evaluated. [•] The surface chemistry was studied the X-ray photoelectron spectroscopy. [•] The MOS capacitor of ZrO2/GaAs exhibits superior electrical characteristics. [•] The interfacial trap density was significantly reduced. [ABSTRACT FROM AUTHOR]

Abstract: The fabrication of condensed silica and mesoporous silica coated spinel CoFe2O4 and FeCo alloy magnetic nanocomposites are reported. The encapsulation of well-defined 5nm thick uniform silica layer on CoFe2O4 magnetic nanoparticles was performed. The formation of mesopores in the shell was a consequence of removal of organic group of the precursor through annealing. The NiO nanoparticles were loaded into the mesoporous silica. The mesoporous silica shells leads to a larger coercivity than that of pure CoFe2O4 magnetic nanoparticles due to the decrease of interparticle interactions and magneto-elastic anisotropy. In addition, the FeCo nanoparticles were coated by condensed and mesoporous silica. The condensed silica can protect the reactive FeCo alloy from oxidation up to 300°C. However, saturation magnetization of FeCo nanoparticles coated by silica after 400°C annealing is dramatically decreased due to the oxidation of the FeCo core. The mesoporous silica coated magnetic nanostructure loaded with NiO as a final product could be used in the field of biomedical applications. [Copyright &y& Elsevier]

Abstract: We report almost perfectly vertically aligned ZnO nanorod arrays synthesized by the hydrothermal route at considerably lower temperature on a sputtered Al:ZnO seed layer using different growth strategies. The nanorod arrays demonstrate remarkable alignment along the c-axis over a large area. Several barrier layers, such as ZnO, Al2O3, BaTiO3 and SiO2, were introduced to form the p-i-n junction to reduce the leakage current. The photocurrent is significantly reduced in nanorod arrays on AZO/SiO2/p-Si heterojunction due to multiple scattering phenomena from ZnO hexagonal facets associated with the nanorod arrays. This research may open up venues for various optical and opto-electronic applications where highly aligned nanostructures are desired. [Copyright &y& Elsevier]

Abstract: CuIn(1− x )Ga x Se2 (CIGS) thin films were prepared by one-step electro-deposition technique from a salt bath coupled with thiocyanate complex electrolytes followed by annealing in argon atmosphere at 300°C. The influence of deposition reduction potentials as well as the salt concentrations on the structure, morphology, composition and the optical properties were performed. A reproducible Cu–In–Ga–Se precursor layer deposition with consistent composition control was demonstrated. The as-deposited films exhibit an amorphous behavior; however the films displayed good crystallization after annealing. The films show very uniform and dense grain formation with platelet-like nanostructures. The optical properties of the films are modified due to annealing. The electrical conductivity measurements demonstrate that the transport mechanism is influenced by three different temperature regions: the ionization, extrinsic and intrinsic regions, respectively, as found in other semiconductors. However, the annealed films display downturn in conductivity at low temperature indicating that there may be trapping at localized sites or scattering of the free carriers, which may be attributed to the over growth and defect sites. The electro-deposition technique demonstrates promise of growing high-quality CIGS thin films. [Copyright &y& Elsevier]