Symbolic dynamic filtering for image analysis: theory and experimental validation

Recent literature has reported the theory of symbolic dynamic filtering (SDF) of one-dimensional time-series data and its various applications for anomaly detection and pattern recognition. This paper extends the theory of SDF in the two-dimensional domain, where symbol sequences are generated from image data (i.e., pixels). Given the symbol sequence, a probabilistic finite state automaton (PFSA), called the D-Markov machine, is constructed on the principles of Markov random fields to incorporate the spatial information in the local neighborhoods of a pixel. The image analysis algorithm has been experimentally validated on a computer-controlled fatigue test apparatus that is equipped with a traveling optical microscope and ultrasonic flaw detectors. The surface images of test specimens, made of a polycrystalline alloy, are analyzed to detect and quantify the evolution of fatigue damage. The results of two-dimensional SDF analysis are in close agreement with those obtained from analysis of one-dimensional time-series data from the ultrasonic sensor, which are simultaneously generated from the same test specimen.     

Effect of lanthanum doping on electrical and electromechanical properties of Ba1−x La x TiO3

The effect of lanthanum doping is studied on ferroelectric properties of Ba_1- x _La xTiO₃ withx = 0.0005, 0.001, 0.003 prepared through solid state sintering route. Dielectric and impedance spectroscopic studies have been carried out. The tetragonal distortion of the unit cell decreased and ferroelectric transition temperature,T _cincreased with the increase of lanthanum content. Combined impedance and admittance spectroscopy was used to analyse impedance data. The electromechanical parameters were calculated from the resonant and anti-resonant frequencies from vector admittance plots. The electromechanical coefficients for Ba_1−xLa_xTiO₃ withx = 0.003 were found to be much larger than that of pure barium titanate.     

A Framework to Implement Supply and Demand Side Contingency Management in Reliability Assessment of Restructured Power Systems

This paper presents a framework to implement supply and demand side contingency management in the reliability assessment of hybrid power markets. A model for the independent system operator (ISO) to coordinate reserve and load curtailment bids for contingency states is introduced to balance reliability worth and reliability cost. The load curtailments and generation re-dispatch for a contingency state are determined based on minimizing the market interruption cost using an optimization technique. A nonsequential Monte Carlo simulation technique based on this framework has been proposed to evaluate the customer reliability of restructured power systems with the hybrid market model. The modified IEEE Reliability Test System (RTS) is used to illustrate the proposed technique     

Be better or be merry: How mood affects self-control.

In 6 studies, the authors tested whether the effect of mood on self-control success depends on a person's accessible goal. We propose that positive mood signals a person to adopt an accessible goal, whereas negative mood signals a person to reject an accessible goal; therefore, if a self-improvement goal is accessible, happy (vs. neutral or unhappy) people perform better on self-control tasks that further that goal. Conversely, if a mood management goal is accessible, happy people abstain from self-control tasks because the tasks are incompatible with this goal. This pattern receives consistent support across several self-control tasks, including donating to charity, demonstrating physical endurance, seeking negative feedback, and completing tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Progress towards marketable earth-abundant chalcogenide solar cells

Kesterite-related photovoltaic materials are considered a promising alternative to CdTe and Cu(In,Ga)(S,Se)₂ absorbers, primarily because they are not reliant on scarce elements such as indium and tellurium or the heavy metal cadmium. Recently, we reported a performance breakthrough for this materials class, reaching by a simple hydrazine-based deposition technique 9.6% power conversion efficiency for Cu₂ZnSn(S,Se)₄ devices (40% improvement over vacuum-based methods). Here, more detailed characterization for a hydrazine-prepared device shows the potential of this technology for further efficiency improvement. We also present initial device results for Cu₂ZnSn(S,Se)₄ films deposited using a mixed water-hydrazine-based solvent, yielding devices with 8.1% efficiency.     

Augmentation of heat transfer through passive techniques

The thermal performance of energy preservation systems is greatly improved by increasing miniaturization and boosting. These are imaginative (or Promethean) techniques to enhance heat transfer. Enhancement methods of heat transfer draw great attention in front of the industrial sector because of their ability to provide energy savings and raise the economic efficiency of thermal systems. Three techniques these methods are categorized; those are active, passive, and compound. Different types of components are used in passive methods because of the transfer/working fluid flow path to the enhancement of the heat transfer rate. In this article, the subject of the review was the passive heat transfer enhancement methods including inserts (conical strips, winglets, twisted tapes, baffles), porous materials, coil/helical/spiral tubes, rough surfaces (corrugated/ribbed surfaces), extended surfaces (fins) and nanofluids (mono and hybrid nanofluid). Recent passive heat transfer enhancement techniques are studied in this article as they are cost-effective and reliable, and also comparably passive methods do not need any extra power to promote the energy conversion systems' thermal efficiency than active methods. In the passive approaches, various components are applied to the heat transfer/working fluid flow path to improve the heat transfer rate. The passive heat transfer enhancement methods studied in this article include inserts (twisted tapes, conical strips, baffles, winglets), extended surfaces (fins), porous materials, coil/helical/spiral tubes, rough surfaces (corrugated/ribbed surfaces), and nanofluids (mono and hybrid nanofluid). From the pioneers' research work, it is clear that a lower twist ratio and lower pitch, lesser winglet angles can provide more heat transfer rate and a little bit more friction factor. In the case of nanofluids, a little bit of pumping power is enhanced. Finally, heat transfer enhancement is compared with the thermal performance factor, which is more than unity.     

Corrosion Behavior of Ti-Si-B-C Nanocomposite Hard Coating with Different Si Contents on 4130 Steel

Metallurgical and Materials Transactions A - Microstructural, mechanical and electrochemical properties of a Ti-Si-B-C nanocomposite coating with different Si percentages on 4130 steel were...     

Comparison of power generation of electrochemically active bacteria isolated from the biofilm of single chambered multi-electrode microbial fuel cell developed using Capra hircus rumen fluid

In the current study, a modified single chambered multi-electrode microbial fuel cell was constructed using carbon electrodes, which produced a maximum power density of 25 mW/m². Four electrochemically active bacteria were obtained from the biofilm of the single chambered microbial fuel cell operated with Capra hircus rumen fluid collected from a slaughter house. These bacteria were characterized using 16S rRNA analysis and have been identified as Cloacibacterium normanense strain RA1, Micrococcus luteus strain RA2, Diaphorobacter oryzae strain RA3, and Pseudomonas aeruginosa strain RA5. Cloacibacterium normanense strain RA1 showed a steady increase in power density till the 6th day and reached a maximum of 51 mW/m² on the same day. The electron transferability of anodic biofilm was studied using cyclic voltammetry. It was found that C. normanense strain RA1, D. oryzae strain RA3, and P. aeruginosa strain RA5 showed oxidation and reduction potential while M. luteus strain RA2 showed only reduction potential.     

Silver nanoparticles: Large scale solvothermal synthesis and optical properties

Silver nanoparticles have been successfully synthesized by a simple and modified solvothermal method at large scale using ethanol as the refluxing solvent and NaBH₄ as reducing agent. The nanopowder was investigated by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), UV-visible and BET surface area studies. XRD studies reveal the monophasic nature of these highly crystalline silver nanoparticles. Transmission electron microscopic studies show the monodisperse and highly uniform nanoparticles of silver of the particle size of 5 nm, however, the size is found to be 7 nm using dynamic light scattering which is in good agreement with the TEM and X-ray line broadening studies. The surface area was found to be 34.5 m²/g. UV-visible studies show the absorption band at ∼425 nm due to surface plasmon resonance. The percentage yield of silver nanoparticles was found to be as high as 98.5%.     

Study of electrical and microstructure properties of high dielectric hafnium oxide thin film for MOS devices

Hafnium oxide (HfO₂) has emerged as the most promising highkdielectric for MOS devices. As-deposited sputtered HfO₂ thin films have large number of defects resulting in increased oxide charge and leakage current. In this paper the effect of sputtering voltage, bias sputtering and post deposition thermal annealing is investigated. The I–V and C–V characteristics of the dielectric film are studied employing Al–HfO₂–Si MOS capacitor structure. It is found that oxide charge increases with increasing sputtering voltage. Thermal annealing in oxygen reduces the interface/oxide charges and leakage current. It is shown that applying substrate bias during film deposition leakage current is further reduced by an order of magnitude. The microstructure of thin film is examined by AFM. The reduction in surface roughness with bias sputtering is shown. The experimental results are presented and discussed for device application.