SLOM: a new measure for local spatial outliers

We propose a measure, spatial local outlier measure (SLOM), which captures the local behaviour of datum in their spatial neighbourhood. With the help of SLOM, we are able to discern local spatial outliers that are usually missed by global techniques, like “three standard deviations away from the mean”. Furthermore, the measure takes into account the local stability around a data point and suppresses the reporting of outliers in highly unstable areas, where data are too heterogeneous and the notion of outliers is not meaningful. We prove several properties of SLOM and report experiments on synthetic and real data sets that show that our approach is novel and scalable to large datasets. Sanjay Chawla is a Senior Lecturer in the School of Information Technologies at the University of Sydney. His research interests span the area of data mining and spatial database management. He is a co-author of the textbook “Spatial Databases: A Tour”, which is published by Prentice Hall. His research work has appeared in leading publications, including IEEE Transaction on Knowledge and Data Engineering and GeoInformatica. He received his Ph.D. in Mathematics from the University of Tennessee, USA. Pei Sun is currently a Ph.D. student in the School of Information Technology, Sydney University, Australia. His research interests include data mining and spatial database. He received his M.E. degree from the University of New South Wales, Sydney, Australia, in 2002 and a B.E. degree from Beijing Forestry University, China, in 1990.     

Swift heavy ion induced modifications of optical and microstructural properties of silver–fullerene C60 nanocomposite

In this paper, we study the optical and microstructural properties of silver–fullerene C₆₀ nanocomposite and their modifications induced by swift heavy ion irradiation. Silver nanoparticles embedded in fullerene C₆₀ matrix were synthesized by co-deposition of silver and fullerene C₆₀ by thermal evaporation. The nanocomposite thin films were irradiated by 120 MeV Ag ions at different fluences ranging from 1 × 10¹² to 3 × 10¹³ ions/cm². Optical absorption studies revealed that the surface plasmon resonance of Ag nanoparticles showed a blue shift of ～49 nm with increasing ion fluence up to 3 × 10¹³ ions/cm². Transmission electron microscopy and Rutherford backscattering spectroscopy were used to quantify particle size and metal atomic fraction in the nanocomposite film. Growth of Ag nanoparticles was observed with increasing ion fluence. Raman spectroscopy was used to understand the effect of heavy ion irradiation on fullerene matrix. The blue shift in plasmonic wavelength is explained by the transformation of fullerene C₆₀ matrix into amorphous carbon.     

Metal-matrix composites in ground transportation

Metal-matrix composites (MMCs) are used in a variety of automotive and other ground transp ortation applications. This article provides a brief overview of the major applications of MMCs in ground transportation. The main attractive features of MMCs are: high strength-to-weight ratio, enhanced mechanical and thermal properties over conventional materials, improved fatigue and creep characteristics, better wear resistance, and general tailorability of properties. Because the transportation industry is extremely cost-sensitive, reducing the manufacturing costs of MMC components will aid in the use of MMCs.     

Encapsulation of extract prepared from irradiated onion scales in alginate beads: a potential functional food ingredient

Onion scales were irradiated and the effects of irradiation on their bioactive properties were studied. The antioxidant and antibacterial activities of extract prepared from irradiated onion scales (upto 6 kGy) were comparable to the extract prepared from non-irradiated onion scales. OSE (0–6%) were encapsulated in 2% alginate beads. The beads containing 6% OSE had the highest a* and the lowest L* values as compared to neat beads that were prepared without OSE. The size of the beads reduced significantly from 2.42 mm (0% OSE) to 2.05 mm (6% OSE). The moisture content of neat (0% OSE) beads was 95.94% as compared to 93.86% in beads incorporated with 6% OSE. Alginate beads containing 6% OSE had the maximum swelling capacity. On basis of DPPH radical scavenging antioxidant assay it was observed that alginate beads containing 6% OSE showed the maximum antioxidant activity. In simulated gastric and intestinal fluid, the antioxidant activity of the beads containing OSE was retained. Irradiated minced chicken muscles containing 6% OSE alginate beads had lower TBARS value (2.0 mg MDA kg^?1 meat) as compared to 3.3 mg MDA kg^?1 meat for irradiated meat with 0% OSE. There was significant difference (almost 2 log cycle reduction) in the growth of Staphylococcus aureus, Pseudomonas fluorescens in chicken muscle during chilled storage when OSE encapsulated beads were incorporated. Hence, irradiation of onion scales and its encapsulation in alginate beads has a great potential as a functional ingredient in various food products.     

Void reactivity decomposition for the Sodium-cooled Fast Reactor in equilibrium fuel cycle

The Sodium-cooled Fast Reactor (SFR) is one of the most promising Generation IV systems with many advantages, but has one dominating neutronic drawback – a positive sodium void reactivity. The aim of this study is to develop and apply a methodology, which should help better understand the causes and consequences of the sodium void effect. It focuses not only on the beginning-of-life (BOL) state of the core, but also on the beginning of open and closed equilibrium (BOC and BEC, respectively) fuel cycle conditions. The deeper understanding of the principal phenomena involved may subsequently lead to appropriate optimization studies.     

Structural and Energetic Impact of Non-natural 7-Deaza-8-azaguanine, 7-Deaza-8-azaisoguanine,and Their 7-Substituted Derivatives on Hydrogen-Bond Pairing with Cytosine and Isocytosine

The impact of 7-deaza-8-azaguanine (DAG) and 7-deaza-8-azaisoguanine (DAiG) modifications on the geometry and stability of the G:C Watson–Crick (cWW) base pair and the G:iC and iG:C reverse Watson–Crick (tWW) base pairs has been characterized theoretically. In addition, the effect on the same base pairs of seven C7-substituted DAG and DAiG derivatives, some of which have been previously experimentally characterized, has been investigated. Calculations indicate that all of these modifications have a negligible impact on the geometry of the above base pairs, and that modification of the heterocycle skeleton has a small impact on the base-pair interaction energies. Instead, base-pair interaction energies are dependent on the nature of the C7 substituent. For the 7-substituted DAG-C cWW systems, a linear correlation between the base-pair interaction energy and the Hammett constant of the 7-substituent is found, with higher interaction energies corresponding to more electron-withdrawing substituents. Therefore, the explored modifications are expected to be accommodated in both parallel and antiparallel nucleic acid duplexes without perturbing their geometry, while the strength of a base pair (and duplex) featuring a DAG modification can, in principle, be tuned by incorporating different substituents at the C7 position.     

EFFECT OF THE DROPLET AGGLOMERATION ON THE DESIGN OF SPRAY DRYER TOWERS

ABSTRACT

The agglomeration of water droplets along the distance from the atomising nozzle was determind experimentally. The effect of the droplet agglomeration upon the required height of the spray dryer is computed for different nozzle sizes and different gas temperatures.     

Comparison of measured and calculated reaction rate distributions in an scwr-like test lattice

High resolution gamma-ray spectroscopy measurements were performed on 61 rods of an SCWR-like fuel lattice, after irradiation in the central test zone of the PROTEUS zero-power research reactor at the Paul Scherrer Institute in Switzerland. The derived reaction rates are the capture rate in ²³⁸U (C₈) and the total fission rate (F_tot), and also the reaction rate ratio C₈/F_tot. Each of these has been mapped rod-wise on the lattice and compared to calculated results from whole-reactor Monte Carlo simulations with MCNPX. Ratios of calculated to experimental values (C/E’s) have been assessed for the C₈, F_tot and C₈/F_tot distributions across the lattice. These C/E’s show excellent agreement between the calculations and the measurements. For the ²³⁸U capture rate distribution, the 1σ level in the comparisons corresponds to an uncertainty of ±0.8%, while for the total fission rate the corresponding value is ±0.4%. The uncertainty for C₈/F_tot, assessed as a reaction rate ratio characterizing each individual rod position in the test lattice, is significantly higher at ±2.2%. To determine the reproducibility of these results, the measurements were performed twice, once in 2006 and again in 2009. The agreement between these two measurement sets is within the respective statistical uncertainties.     

Preparation and evaluation of alpha-cellulose sulfate based new heterogeneous catalyst for production of biodiesel

Alpha-cellulose obtained from wood sawdust wastes in 29.0% yield was reacted with sulfuric acid to produce alpha-cellulose sulfate materials. These catalyst materials were characterized by Fourier transform infrared and specular reflectance-UV spectroscopy, scanning electron microscopy, and laser scattering particle size distribution. The concentration of sulfate groups on the cellulosic matrix was determined by turbidimetry. The obtained alpha-cellulose sulfates can be used as efficient heterogeneous catalysts for biodiesel production from palm oil when evaluated with methylation of palmitic acid and oleic acid as the model reaction. The density of sulfate functional groups on the alpha-cellulose sulfate materials was 2.18–16.74% wt/wt as determined by turbidimetry. Standardization of deployed alpha-cellulose sulfate catalysts was achieved using different ratios of alpha-cellulose and sulfate (1:0.5, 1:1, 1:2, and 1:4 m/v). Additionally, the Bronsted acid sites on the alpha-cellulose sulfate catalyst play a pivotal role in the catalytic process.     

Oxidation Behaviour of HVOF Sprayed NiCrAlY and NiCrAlY-20SiC Coatings on T-91 Boiler Tube Steel

Protection of Metals and Physical Chemistry of Surfaces - In present study, the high temperature oxidation behavior of HVOF sprayed NiCrAlY alloy coating and NiCrAlY–20SiC composite coating...