The Effects of IT Management on Technology Process Integration

This study examines the impacts of technology management on organization-wide technology integration in an education setting. It uses survey questionnaire responses from education administrators in the southwest region of the United States to evaluate the relationship between technology management and technology integration. Results show technology management significantly and positively influences organization-wide technology integration, infrastructure, and training in an education setting. Additional findings support prior research in other areas that suggest technology-related training and infrastructure positively influence organization-wide technology integration. In a post hoc analysis, we found that training and infrastructure partially mediate the relationship between technology management and technology integration. These findings provide insight into how to achieve technology integration that is relevant to managers, educational agencies, and policy-makers who help develop and implement plans for organizational technology integration. Theoretical and practical implications also are discussed.     

Temperature Dependence of Hardness in Yttria-Stabilized Zirconia Single Crystals

The temperature dependence of hardness and microcracking in single-crystal 9.5-mol%-Y₂O₃-fully-stabilized cubic-ZrO₂ was studied as a function of orientation. Crack lengths increased with increased temperature up to 500°C; above 800°C, no cracks were found, indicating an indentation brittle-to-ductile transition of ∼800°C. The temperature dependence of hardness was reduced around 500°C. Etching studies to delineate the plastic zone around and below indents identified the operative slip systems. The role of dislocations and their interactions within the plastic zone on the hardness and indentation fracture behavior of cubic-ZrO₂ are discussed.     

Numerical and experimental studies of bubble growth during the microcellular foaming process

A new experimental technique for studying the dynamics of bubble growth in thermoplastics using scanning electron microscopy is developed. The influence of temperature, saturation pressure, molecular weight, and the nature of physical blowing agent are investigated. The experimental results show that, the above, process variables control the growth of foams during processing. The existing Newtonian model for the growth of a single bubble in an infinite amount of polymer has been modified to account for the non-Newtonian effects by modeling the polymer as a power law fluid. The experimental data has been compared with the appropriate viscoelastic cell model which considers the growth of closely spaced spherical bubbles during the foaming process. The simulation results indicate that the predictions of the cell model are in qualitative agreement with the trends of the experimental data and the quantitative agreement is reasonable. The cell model also gives an equilibrium radius which agrees with the experimental data. Other viscous models do not predict the equilibrium radius of the bubble and underpredict the experimental data.     

Microstructural Evolution in Near-Eutectic Yttrium Silicate Compositions Fabricated from a Bulk Melt and as an Intergranular Phase in Silicon Nitride

Near-eutectic composition Y₂O₃─SiO₂ melts were formed as bulk samples or as an intergranular phase in Si₃N₄. Upon cooling to room temperature the bulk material partially crystallized to γ-Y₂-Si₂O₇ whereas the intergranular phase was glass. On heat-treating at 1500°C the bulk material transformed to γ-Y₂Si₂O₇ whereas the intergranular glass crystallized first to γ-Y₂Si₂O₇ and then to β-Y₂Si₂O₇. Possible reasons for the different behavior are discussed.     

Elucidation of the effects of competitive adsorption of Cland Br ions on the initial stages of Pt surface oxidation by means of electrochemical nanogravimetry

At anodically polarized Pt electrodes in aqueous H₂SO₄ solution, Cl⁻ and Br⁻ ions are adsorbed competitively with the oxygen species that is deposited between 0.8 and 1.1 V, RHE, forming the initial stage of anodic oxide-film generation at Pt anodes. The Cl⁻ adsorption leads to selective and progressive blocking of the first 50% of coverage by O species at the Pt surface with increasing Cl⁻ concentration (commencing at 10⁻⁷ M) while relatively little effect is seen on the place-exchanged Pt/O→O/Pt lattice that is formed beyond 1.10 V, except at Cl⁻ concentrations greater than 10⁻¹ M, where evolution of Cl₂ commences and hence interferes. The states of co-adsorbed Cl and O-containing species, and their relative surface coverages, determine the nature of the electrocatalytic surface on which anodic Cl₂ evolution takes place. How this selective blocking behavior arises has not previously been well understood. In the present paper, complementary applications of the electrochemical quartz crystal nanobalance (EQCN) technique with cyclic voltammetry are brought to bear on this matter and provide new results at high levels of sensitivity and reproducibility which help to elucidate the competitive and selective chemisorption effects of Cl⁻ at Pt anodes. The results obtained with Cl⁻ ions exhibit some peculiarities which comparative experiments on Br⁻ adsorption help to rationalize.     

Evaluating multimedia features and fusion for example-based event detection

Multimedia event detection (MED) is a challenging problem because of the heterogeneous content and variable quality found in large collections of Internet videos. To study the value of multimedia features and fusion for representing and learning events from a set of example video clips, we created SESAME, a system for video SEarch with Speed and Accuracy for Multimedia Events. SESAME includes multiple bag-of-words event classifiers based on single data types: low-level visual, motion, and audio features; high-level semantic visual concepts; and automatic speech recognition. Event detection performance was evaluated for each event classifier. The performance of low-level visual and motion features was improved by the use of difference coding. The accuracy of the visual concepts was nearly as strong as that of the low-level visual features. Experiments with a number of fusion methods for combining the event detection scores from these classifiers revealed that simple fusion methods, such as arithmetic mean, perform as well as or better than other, more complex fusion methods. SESAME’s performance in the 2012 TRECVID MED evaluation was one of the best reported.     

Characterization and Catalytic Behavior of VO x -CeO2 Catalysts for the Oxidative Dehydrogenation of Propane

A series of ceria-supported vanadium catalysts was prepared via impregnation of the support with an ammonium metavanadate solution. The 723 K calcined samples were tested for propane oxydehydrogenation (ODH) activity and selectivity. The sample exhibiting the highest propane conversion was found to be the ceria support material itself, although this showed essentially no selectivity towards propene. An optimum propene yield of 4.2% was obtained at 673 K for the 6 wt% V₂O₅-CeO₂ sample. Conversion decreased with increasing V loading which was attributed to the formation of cerium vanadate (CeVO₄). This phase was found in all samples after calcination, its abundance rising in proportion to the V loading. In the 6 wt% V₂O₅ catalyst hydrated surface VO_x species were present, although they underwent conversion to CeVO₄ at temperatures above 573 K. The low reducibility of these surface vanadates was linked to the oxidation activity. It is inferred that surface polyvanadate species are responsible for the selective ODH of propane with V-O-V and/or V-O-Ce being the active oxygen species.     

In vitro cytotoxicity of Manville Code 100 glass fibers: Effect of fiber length on human alveolar macrophages

Background  

Synthetic vitreous fibers (SVFs) are inorganic noncrystalline materials widely used in residential and industrial settings for insulation, filtration, and reinforcement purposes. SVFs conventionally include three major categories: fibrous glass, rock/slag/stone (mineral) wool, and ceramic fibers. Previous in vitro studies from our laboratory demonstrated length-dependent cytotoxic effects of glass fibers on rat alveolar macrophages which were possibly associated with incomplete phagocytosis of fibers ≥ 17 μm in length. The purpose of this study was to examine the influence of fiber length on primary human alveolar macrophages, which are larger in diameter than rat macrophages, using length-classified Manville Code 100 glass fibers (8, 10, 16, and 20 μm). It was hypothesized that complete engulfment of fibers by human alveolar macrophages could decrease fiber cytotoxicity; i.e. shorter fibers that can be completely engulfed might not be as cytotoxic as longer fibers. Human alveolar macrophages, obtained by segmental bronchoalveolar lavage of healthy, non-smoking volunteers, were treated with three different concentrations (determined by fiber number) of the sized fibers in vitro. Cytotoxicity was assessed by monitoring cytosolic lactate dehydrogenase release and loss of function as indicated by a decrease in zymosan-stimulated chemiluminescence.