Model driven edge detection

Standard edge detectors fail to find most relevant edges, finding either too many or too few, because they lack a geometric model to guide their search. We present a technique that integrates both photometric and geometric models with an initial estimate of the boundary. The strength of this approach lies in the ability of the geometric model to overcome various photometric anomalies, thereby finding boundaries that could not otherwise be found. Furthermore, edges can be scored based on their goodness of fit to the model, thus allowing one to use semantic model information to accept or reject the edges.     

Multiperspective Approach to Exploring Comprehensive Cause Factors for Interface Issues

The severity of interface issues and the necessity of interface management (IM) have not received adequate recognition from both industry and academia. The understanding of interface issues is still insufficient and the proposed or employed measures are unilateral, which result in unsatisfactory IM performance in construction projects. After establishing IM’s importance in the construction industry, this paper presents a multiperspective approach that systematically explores comprehensive cause factors for various interface issues. From six interrelated perspectives, namely people/participants, methods/processes, resources, documentation, project management, and environment, hierarchical cause factors are identified and presented in a structured way. These cause factors are further converted into a series of interface management and control elements that allow for the development of an object data model and a systematic model-based IM strategy dealing with all interface issues. The multiperspective approach outperforms other research methods that analyze selected interface issues in a loose and isolated way. The findings contribute a holistic view of what causes interface issues as well as provide a solid theoretical basis for practitioners and researchers to seek all-around IM solutions.     

Multispecies in situ monitoring of a static internal combustion engine by near-infrared diode laser sensors

A multispecies near-infrared diode laser spectrometer has been constructed for measurements of carbon monoxide, carbon dioxide, and methane directly in the exhaust of a static internal combustion engine. A wavelength modulation-division multiplexing scheme was implemented for the two distributed feedback diode lasers. Gas concentration variations were observed for changes in operating conditions such as increasing and decreasing the throttle, adjusting the air-fuel ratio, and engine start-up.     

Lattice dynamics of the Zn-Mg-Sc icosahedral quasicrystal and its Zn-Sc periodic 1/1 approximant

Quasicrystals are long-range-ordered materials that lack translational invariance, so the study of their physical properties remains a challenging problem. Here, we have carried out inelastic-X-ray- and neutron-scattering experiments on single-grain samples of the Zn-Mg-Sc icosahedral quasicrystal and of the Zn-Sc periodic cubic 1/1 approximant, with the aim of studying the respective influence of the local order and of the long-range order (periodic or quasiperiodic) on lattice dynamics. Besides the overall similarities and the existence of a pseudo-gap in the transverse dispersion relation, marked differences are observed, the pseudo-gap being larger and better defined in the approximant than in the quasicrystal. This can be qualitatively explained using the concept of a pseudo-Brillouin-zone in the quasicrystal. These results are compared with simulations on atomic models and using oscillating pair potentials, and the simulations reproduce in detail the experimental results. This paves the way for a detailed understanding of the physics of quasicrystals.     

High resolution mapping of surface reduction in ceria nanoparticles

Surface reduction of ceria nano octahedra with predominant {111} and {100} type surfaces is studied using a combination of aberration-corrected Transmission Electron Microscopy (TEM) and spatially resolved electron energy-loss spectroscopy (EELS) at high energy resolution and atomic spatial resolution. The valency of cerium ions at the surface of the nanoparticles is mapped using the fine structure of the Ce M(4,5) edge as a fingerprint. The valency of the surface cerium ions is found to change from 4+ to 3+ owing to oxygen deficiency (vacancies) close to the surface. The thickness of this Ce(3+) shell is measured using atomic-resolution Scanning Transmission Electron Microscopy (STEM)-EELS mapping over a {111} surface (the predominant facet for this ceria morphology), {111} type surface island steps and {100} terminating planes. For the {111} facets and for {111} surface islands, the reduction shell is found to extend over a single fully reduced surface plane and 1-2 underlying mixed valency planes. For the {100} facets the reduction shell extends over a larger area of 5-6 oxygen vacancy-rich planes. This finding provides a plausible explanation for the higher catalytic activity of the {100} surface facets in ceria.     

Analysis of Deformed Oxide Layers Grown on Steel

The deformation of the oxide layer grown in ultra low carbon steel was studied by means of electron backscattered diffraction analyses. Samples of the steel were reheated for shorts periods of time at 1050 °C in a chamber designed to obtain thin scale layers before deforming them by plane strain compression at temperatures ranging from 650 to 1050 °C. Microstructural analyses showed that the oxide layer was made almost exclusively of wustite that is ductile when deformed above 900 °C. It is found that wustite develops texture components of the cube and rotated cube type while growing; these components rotate towards ??201?? {100} components once a certain degree of deformation is achieved. Undeformed ferrite close to the oxide layer shows weak ??201?? {100} components that rotate into weak rotated cube components when the substrate is deformed in the austenite range and to strong ??554?? {225} components when deformed in ferrite. Rolling trials carried out in an experimental mill showed similar trends.     

Melt Mixing of a Styrene/Butadiene Copolymer with an Aqueous Slurry of Zirconium Phosphate as a Route for the Preparation of Nanocomposites

The preparation of functional nanocomposites by dispersion of a synthetic lamellar α‐ZrP within a styrene/butadiene random copolymer during melt compounding is described. It is shown how the physical and chemical incompatibility of filler and polymer can be overcome, and problems arising from the low viscosity ratio between slurry and polymer matrix are discussed. The aqueous phase can easily be eliminated at the end of the process. The dispersion of the ZrP requires the use of intercalants, and alkylamines were used for this purpose. XRD and TEM are used to characterize the degree of organization of ZrP in the slurries and in the matrix. DMA helps to understand the origin of the limited reinforcing effect.

     

Finite element modeling for optimization of microwave heating of in‐shell eggs and experimental validation

Considering microwave (MW) heating as a viable alternative for in‐shell pasteurization of eggs, after the simulation of the MW heating process by using a finite element model, process optimization was carried out to determine the most effective procedure and design for the process. The varying parameters obtained by using different modeling techniques for MW heating of in‐shell eggs were optimized. Laboratory‐scale experimental trials were conducted to test the validity and effectiveness of the optimized parameters. The optimal parameters set forth were found to be more efficient in terms of heating time and uniformity. MW heating appeared to be a viable alternative for the pasteurization of in‐shell eggs. Copyright © 2011 John Wiley & Sons, Ltd.     

Purification and characterization of a new bacteriocin active against Campylobacter produced by Lactobacillus salivarius SMXD51

Strain SMXD51, isolated from chicken ceca and identified as Lactobacillus salivarius, produced a component that inhibits the growth of Gram-positive and Gram-negative bacteria and especially Campylobacter jejuni. The active peptide from the cell-free supernatant of Lb. salivarius SMXD51 was purified in three steps: (i) precipitation with 80% saturated ammonium sulfate, (ii) elution on a reversed phase SPE UPTI-CLEAN cartridge using different concentrations of acetonitrile, (iii) final purification by reversed phase HPLC on a C₁₈ column. The mode of action of this peptide of 5383.2 Da was identified as bactericidal, and its amino acid composition was established. This new bacteriocin SMXD51 appears potentially very useful to reduce Campylobacter in poultry prior to processing.