The importance of information localization in scene gist recognition.

People can recognize the meaning or gist of a scene from a single glance, and a few recent studies have begun to examine the sorts of information that contribute to scene gist recognition. The authors of the present study used visual masking coupled with image manipulations (randomizing phase while maintaining the Fourier amplitude spectrum; random image structure evolution [RISE]; J. Sadr & P. Sinha, 2004) to explore whether and when unlocalized Fourier amplitude information contributes to gist perception. In 4 experiments, the authors found that differences between scene categories in the Fourier amplitude spectrum are insufficient for gist recognition or gist masking. Whereas the global 1/f spatial frequency amplitude spectra of scenes plays a role in gist masking, local phase information is necessary for gist recognition and for the strongest gist masking. Moreover, the ability to recognize the gist of a target image was influenced by mask recognizability, suggesting that conceptual masking occurs even at the earliest stages of scene processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impact of Zinc oxide nanoparticles on eggplant (S. melongena): studies on growth and the accumulation of nanoparticles

The increasing use of nanoparticles and their occurrence in the environment has made it imperative to elucidate their impact on the environment. Although several studies have advanced the authors’ understanding of nanoparticle–plant interactions, their knowledge of the exposure of plants to nanoparticles and their effects on edible crop plants remain meager and is often paradoxical. The aim of this study was to increase their knowledge on the effect of zinc oxide (ZnO) nanoparticles on eggplant seed germination and seedling growth. ZnO nanoparticles had a negative effect on the growth of eggplant in plant tissue‐culture conditions, as the growth of seedlings decreased with the increase in the concentration of ZnO nanoparticles. In contrast, ZnO nanoparticles enhanced eggplant growth under greenhouse conditions. The accumulation of ZnO nanoparticles in various parts of eggplant was observed through scanning electron microscopy of both plant tissue‐culture and greenhouse‐raised eggplant seedlings. To the best of their knowledge, this is the first study to report on ZnO nanoparticle accumulation in eggplant and its effect on seed germination and seedling growth.Inspec keywords: crops, zinc compounds, scanning electron microscopy, II‐VI semiconductors, nanoparticles, agriculture, cellular biophysics, nanofabricationOther keywords: plant tissue‐culture, greenhouse‐raised eggplant seedlings, ZnO nanoparticle accumulation, seedling growth, ZnO nanoparticles, nanoparticle–plant interactions, zinc oxide nanoparticles, eggplant seed germination, eggplant growth, ZnO     

Axial mixing in a 15 cm diameter reciprocating plate bubble column

Axial dispersion coefficients (E) in the liquid phase have been measured by unsteady tracer response methods in a 15 cm internal diameter reciprocating plate bubble column, using air and water in countercurrent and cocurrent flow. The operating variables studied were amplitude (0.6–1.27 cm) and frequency (0–5 Hz) of reciprocation, and the superficial velocities of the liquid and gas phases and the spacing between plates. Three types of plate were studied; conventional Karr-type plates with perforation diameters 1.43 cm, plates with smaller (0.635 cm) perforations, and single-perforation (doughnut) plates with internal diameter 7 cm. Measured values of E ranged from about 1 cm²/s to a maximum of 116 cm²/s. In general, the plates with 0.635 cm perforations gave the smallest values of E while the largest values of E were obtained with the doughnut plates, due to vortex ring shedding. The single liquid phase data for the three types of plate were approximately consistent with the correlation of Stevens and Baird (1990). The gas-liquid flow results were interpreted in terms of several different hydrodynamic effects.     

Highly conductive buried n+ layers in lnp:fe created by MeV energy Si,S, and Si/S implantation for application to microwave devices

To obtain highly conductive buried layers in InP:Fe, MeV energy Si, S, and Si/ Simplantations are performed at 200°C. The silicon and sulfer implants gave 85 and 100 percent activation, respectively, for a fluence of 8 × 10¹⁴ cm⁻². The Si/S co-implantation also gave almost 100 percent donor activation for a fluence of 8 × 10¹⁴ cm⁻² of each species. An improved silicon donor activation is observed in the Si/S co-implanted material compared to the material implanted with silicon alone. The peak carrier concentration achieved for the Si/S co-implant is 2 × 10¹⁹ cm³. The lattice damage on the surface side of the profile is effectively removed after rapid thermal annealing. Multiple-energy silicon and sulfur implantations are performed to obtain thick and buried n⁺ layers needed for microwave devices and also hyper-abrupt profiles needed for varactor diodes.     

Intensity tunable optical limiting behaviour of an organic material 2-aminopyridinium succinate succinic acid single crystal

Journal of Materials Science: Materials in Electronics - A mixed solution of 2-aminopyridine and succinic acid, with a 1:1 molar ratio, was kept at room temperature to develop a 2-aminopridinium...     

Effect of Microstructure and Mechanical Properties of Al–Mg Alloy Processed by ECAP at Room Temperature and Cryo Temperature

This research primarily focuses on improving the strength of Al 5083 alloy by both the ECAP and Cryo ECAP methodology. Equal Channel Angular Pressing (ECAP) is one of the best technologies that enable the direct transformation of conventional macro grained metals into sub-micron, ultra-fine and nano grained materials. Fine grain size increases the strength and the fracture toughness of the material and provides the potential for super plastic deformation at moderate temperatures and at high strain rates. The microstructure evolution in Al 5083, subjected to Room Temperature ECAP and Cryo ECAP were analysed. ECAP was carried out using an optimized die with Channel angle ‘?’ = 90°and corner angle ‘Ψ’ = 20° through processing route A and C up to four passes. The results were thoroughly studied using TEM, SEM, and optical microscopic images. Initially the annealed sample had the grain size of 80 µm with the equi-axed grains. In Room Temperature, the hardness values and the mechanical strength were found to be increased from 88 to 410 HV and 306 to 453 MPa after four passes in route A and in route C the strength increased from 390 to 416 MPa after four ECAP passes. Moreover, in Cryo Condition, the sample was processed up to four ECAP passes at route A and route C. The hardness of 153 HV was obtained after four passes in route C and 164 HV obtained after four passes on route A. Additionally, fracture behaviour using SEM, grain size using TEM and crystallite size by X-ray diffraction studies were analyzed. It was observed that the Cryo ECAP showed marginal improvements in mechanical properties relative to the RT ECAP in case of Al 5083.     

Message filters for hardening the Linux kernel

Various mechanisms for hardening the Linux kernel (for example, enforcing system call policies, device driver failure recovery, protection against exploitation of bugs in code) are proposed in the literature. The main problem with these mechanisms is that, they require changes in the kernel code leading to the possibility of introducing new bugs and hence increasing the testing time. We propose a message filter model as an extension to object‐oriented wrappers for the Linux kernel, to dynamically provide various filtering capabilities to the kernel. This model works as a comprehensive framework for specifying system call policies, handling device driver faults, protecting the kernel against exploits of bugs in code etc, without modifying the existing kernel code. This considerably reduces the possibility of creating new bugs in the kernel code. We have integrated policies for system call interception and device driver failure handling, into the Linux kernel (2.6.9), using message filter model. Our experiments show that the overhead due to our filter objects is very low, making it a useful mechanism for providing filtering capabilities to the Linux kernel. Copyright © 2010 John Wiley & Sons, Ltd.     

The Opportunity challenge: A benchmark database for on-body sensor-based activity recognition

There is a growing interest on using ambient and wearable sensors for human activity recognition, fostered by several application domains and wider availability of sensing technologies. This has triggered increasing attention on the development of robust machine learning techniques that exploits multimodal sensor setups. However, unlike other applications, there are no established benchmarking problems for this field. As a matter of fact, methods are usually tested on custom datasets acquired in very specific experimental setups. Furthermore, data is seldom shared between different groups. Our goal is to address this issue by introducing a versatile human activity dataset recorded in a sensor-rich environment. This database was the basis of an open challenge on activity recognition. We report here the outcome of this challenge, as well as baseline performance using different classification techniques. We expect this benchmarking database will motivate other researchers to replicate and outperform the presented results, thus contributing to further advances in the state-of-the-art of activity recognition methods.     

Structural,thermal, dielectric,nonlinear optical properties and DFT investigations of a novel material 2-(6-chloropyridin-3-yl)-N'-(2,3-dihydro-1,4-benzodioxin-6-ylmethylidene)acetohydrazide for optoelectronic applications

A new organic nonlinear optical (NLO) material 2-(6-chloropyridin-3-yl)-N'-(2,3-dihydro-1,4-benzodioxin-6-ylmethylidene)acetohydrazide (CDA) has been synthesized by reflux method. Single crystals were grown by slow evaporation technique and the crystal structure was elucidated by single crystal X-ray diffraction method. Density functional theory (DFT) calculations at B3LYP/6–31+?+?G(d, p) basis set was used to predict the molecular geometry and were carried out further to comprehend the electronic structure, vibrational spectra, natural bonding orbitals (NBO), frontier molecular orbitals (FMO) and molecular electrostatic potential (MEP). An optical transparency at the cut-off wavelength of 355 nm was determined by UV–Vis–NIR spectroscopy. Thermal behavior of CDA was studied by TGA/DTA analysis. The dielectric constant (ε), dielectric loss (tan δ) and AC conductivity as a function of frequency and temperature was studied. Second Harmonic Generation (SHG) efficiency of the CDA was determined using Kurtz and Perry powder technique and was 0.5 times greater than that of the KDP crystal. The third-order nonlinear optical properties were investigated in solution by Z-scan technique using a continuous wave (CW) DPSS laser at the wavelength of 532 nm. The title compound exhibited significant two-photon absorption (β?=?2.228?×?10–4 cm W^?1), nonlinear refraction (n₂?=?1.095?×?10–8 cm² W^?1) and optical limiting (OL threshold?=?2.511?×?103 W cm^?2) under the CW regime. The nonlinear optical parameters were calculated using time-dependent Hartree–Fock (TDHF) method. The overall obtained results suggested that the studied CDA molecule could be a potential NLO material for frequency generator, optical limiters and optical switching applications.

     

Structural,electrical and magnetic properties of cobalt ferrite with Nd3+ doping

A systematic study on the influence of Nd³⁺ substitution on structural,magnetic and electrical properties of cobalt ferrite nanopowders obtained by sol–gel auto-combustion routewas reported.The formation of spinel phasewas confirmed by X-ray diffraction(XRD)data,and percolation limit ofNd3?into the spinel lattice was also observed.Fourier transform infrared spectroscopy(FTIR)bands observed ≈580 and ≈390 cm^(-1 ) support the presence of Fe³⁺ at A andBsites in the spinel lattice.The variation in microstructure was investigated by scanning electronmicroscopy(SEM),and the average grain size varies from 5.3 to 3.3 lm.The substitution of Nd³⁺ significantly affects the formation of pores and grain size of cobalt ferrite.Room-temperature saturation magnetization and coercivity decrease from 60 to 30 mA·m²·g^-1 and 19.9–17.8 mT,respectively,with Nd³⁺ substitution increasing.These decreases in magnetic properties are explained based on the presence of non-magnetic nature of Nd³⁺ concentration and the dilution of super-exchange interaction in the spinel lattice.The room-temperature direct-current electrical resistivity increases with Nd³⁺ concentration increasing,which is due to the unavailability of Fe²⁺ at octahedral B sites.