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Image Processing Procedures For Analysis Of Electron Back Scattering Patterns, N. C. Krieger Lassen, D. Juul Jensen, K. Conradsen

Scanning Microscopy

At present, computer-aided Electron Back Scattering Pattern (EBSP) analysis often requires large amounts of operator time if statistically reliable measurements are needed. This paper presents ways to automatically detect and localize bands in EBSPs and thereby enable fully automatic EBSP analysis. The main focus will be on a procedure using a modified Hough transform by which more than 12 bands in a typical EBSP can be detected and localized. This procedure seems as effective and reliable for extracting the bands of EBSPs as any human operator. The performance of this procedure is compared with that of other image processing procedures.

On Descartes' Presuppositionless Philosophy, W. Tyler Johnson

Undergraduate Honors Capstone Projects

The history of human thought seems to be a quest for truth. Each looking for some evidence of a higher law, the biologist looks at living tissue, the chemist looks in the molecule, and the physicist looks inside the atom while the mathematician looks beyond matter and the theist looks toward God. Uncertainty and ignorance have traditionally been despised and rejected in favor of Knowledge and Rigor by all such scientists. Rene Descartes is commonly understood to be the father of this modernism as he was the first to replace the Church and its authoritarianism with a belief in the …

Calculation Of Barriers To Proton Transfer Using Variations Of Multiconfiguration Self‐Consistent‐Field Methods. Ii. Configuration Interaction, K. Luth, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Various means are tested of including additional electron correlation into multiconfiguration self‐consistent‐field (MCSCF) methods for computing proton transfer potentials in HF₂⁻, H₇N₂⁺, H₃O₂⁻, and H₅O₂⁺. Configuration interaction allowing single excitations (CIS) and configuration interaction with single + double excitations (CISD) calculations are performed following MCSCF expansion of the wave function using various different MCSCF reference wave functions. The CISD results are excellent, being fairly independent of choice of reference space although it is important that the occupied orbitals be balanced between the …

Coverage Dependence Of K Adsorption On Si(100)—2× 1 By Core-Level Photoemission, D. Mark Riffe, G. K. Wertheim, P. H. Citrin, J. E. Rowe

All Physics Faculty Publications

Using core-level photoemission, a coverage-dependent transition in the adsorption of K on Si(100)2×1 is observed. Below ∼0.25 monolayers, a single adsorption is occupied, the asymmetry of the Si-dimer reconstruction is enhanced, and no more than ∼0.05e is transferred from K to Si. Above this coverage, multiple sites are occupied, the dimer configuration becomes more symmetric, and the K overlayer becomes increasingly metallic. These findings resolve a number of conflicting studies of this system.

Simulating Ion Microtomography Data For Improving Reconstruction Quality, A. J. Antolak, A. E. Pontau

Scanning Microscopy

Ion Microtomography (IMT) provides quantitative, fine resolution density imaging of samples for materials characterization. Reconstructed tomographic images are obtained by application of a filtered backprojection algorithm to the collected data. The attainable resolution and data acquisition rate are affected by several parameters. These include the number of ions measured per spot, using either the mean or median residual energy, utilizing Bragg additivity, changing the number of rays or the number of projections and oversampling the data. A tomography simulation computer program is described and used to study the contributions from these effects on the numerical reconstruction of an array of …

Finite Thermal Diffusivity At Onset Of Convection In Autocatalytic Systems: Continuous Fluid Density, J. W. Wilder, Boyd F. Edwards, D. A. Vasquez

All Physics Faculty Publications

The linear stability of exothermic autocatalytic reaction fronts is considered using the viscous thermohydrodynamic equations for a fluid with finite thermal diffusivity. For upward front propagation and a thin front, the vertical thermal gradient near the front is reminiscent of the Rayleigh-Bénard problem of a fluid layer heated from below. The problem is also similar to flame propagation, except that here the front propagation speed is limited by catalyst diffusion rather than by activation kinetics. For small density changes in a laterally unbounded system, the curvature dependence of the front propagation speed stabilizes perturbations with short wavelengths λ<λ_c, …

Structural Artifacts And Advantages Of Cytocentrifugation Of Cells As Viewed By Scanning Electron Microscopy, Mário N. D. Peão, Artur P. Águas, Carlos Moreira De Sá, Nuno R. Grande

Scanning Microscopy

Cytocentrifugation of cell suspensions onto glass slides is a widely used procedure in contemporary cytology. We employed here scanning electron microscopy (SEM) to investigate putative morphological changes induced in cells submitted to cytocentrifugation. The fine structure of murine pleural exudate cells (macrophages mainly) processed by spinning was compared with that of similar cells treated without centrifugation (poly-L-lysine attachment of the cells to glass slides at 1 g). Cells of cytocentrifuged preparations showed a significant increase in diameter and smoothening of the cell surface as compared with the morphology of non-centrifuged cells. Cytocentrifugation also induced the formation of thin elongations coming …

Acquisition Hardware For Imaging, Peter Rez, J. K. Weiss, W. J. De Ruijter

Scanning Microscopy

In electron microscopy images can either be recorded in parallel (Transmission Electron Microscopy) or acquired as the variation in a signal as a probe is scanned over the specimen (Scanning Electron Microscopy). To extract the most information from an image requires that the best possible systems are used for acquiring image data. Ultimately, the limit to information capture is achieved when every electron from the scattering event of interest is recorded. The ideal system can be realised both for parallel recording with scientific grade CCD cameras, and for scanning microscopy with single electron counting electronics. The data rates from these …

Image Delocalisation And High Resolution Transmission Electron Microscopic Imaging With A Field Emission Gun, W. Coene, A. J. E. M. Jansen

Scanning Microscopy

The high spatial and temporal coherence of a field emission gun (FEG) increases the information limit of high-resolution transmission electron microscopes (HRTEM), but has also its implications on the localisation of the high resolution information in the image. In this paper, we present the results of a combined theoretical and experimental study of delocalisation in HRTEM. First, we derive a spatial frequency analysis of the delocalisation for crystal defects. Next, the delocalisation is studied from a real-space point of view, in terms of the impulse-response function, for which an instructive asymptotic mathematical analysis has been set up. Finally, we present …

Dolores River Basin Water Quality Study, Department Of Interior; Bureau Of Reclamation, Technical Service Center; Denver, Co

Elusive Documents

No abstract provided.

1991-1992 Annual Report, Various Authors

Annual Reports

No abstract provided.

Ultrahigh Vacuum Chamber For Synchrotron X-Ray Diffraction From Films Adsorbed On Single-Crystal Surfaces, Jr Dennison, S. K. Wang, S. N. Ehrlich

Journal Articles

An ultrahigh vacuum chamber has been developed for structural analysis of adsorbed films and single-crystal surfaces using synchrotron x-ray diffraction. It is particularly well suited for investigations of physisorbed and other weakly bound films. The chamber is small enough to transport and mount directly on a standard four-axis diffractometer and can also be used independently of the x-ray diffractometer. A low-current, pulse-counting, low-energy electron diffraction/Auger spectroscopy system with a position-sensitive detector enables in situ characterization of the film and substrate while the sample is located at the x-ray scattering position. A closed-cycle He refrigerator and electron bombardment heater provide controlled …

Optimum Trade Intervention In The Presence Of Multinationals, Hamid Beladi, Basudeb Biswas, Gopal Tribedy

Economic Research Institute Study Papers

This paper shows the non-optimality of the free trade policy in a labor-surplus economy where multinational corporations operate in the importable sector with distortions in the capital market. It then examines the welfare implications of alternative trade intervention policies. The paper illustrates that (a) a tariff and a production subsidy to the importable sector reduce welfare, while (b) an export subsidy and a production subsidy to the exportable sector enhance welfare. The optimum subsidy rates necessary to implement the outwardlooking trade policy are also derived in the paper.

Economic Freasibility Of A Processing Facility For "Spent" Laying Hens In Northern Utah, Deevon Bailey, T. F. Glover, Chris Fawson, G. W. Squires, J. L. Park

Economic Research Institute Study Papers

No abstract provided.

Objective Measurement Of The Visual Aspect Of Dry Sausage Slices By Image Analysis, A-C. Roudot, F. Duprat, M.-G. Grotte, G. O'Lidha

Food Structure

The visual aspect of food is a problem very often neglected for different reasons; one being the difficulty of modelling vision. However, it has been shown that , on simple synthetic images, automatic sorting in the same manner as human vision is possible.

Distribution heterogeneity of spots within an image is one important parameter for its characterization. A new algorithm was tested over simple numerical pictures that gave good agreement with visual appreciation. Images of twenty dry sausage slices were analyzed and different factors corresponding to aspect structure were calculated. Principal component analyst:s based on these factors all owed discrimination …

Segmentation Of Pores In Backscattered Images Of Sediments And Soils And Their Relationship To Domain Structure, M. W. Hounslow, N. K. Tovey

Scanning Microscopy

A new technique to quantify variations in pore structure across an image is described in this paper. The method involves several stages as the original images are rarely suitable for simple segmentation by the selection of a single threshold. The processing first involves the application of a Wiener filter to remove imaging artefacts and to sharpen the edge of void/particle contacts. This image reconstruction is followed by the selection of a global threshold based on the relative contrast method, to create a binary image separating the voids from the particles. Such an image can be used to evaluate pore structure …

Light Microscopy Measurements Of Ice Recrystallization In Frozen Corn Starch Pastes Using Isothermal Freeze Fixation, C. Ferrero, M. N. Martino, N. E. Zaritzky

Food Structure

Isothermal freeze fixation was used to analyze ice recrystallization by light microscopy in a 10 % (W/W) frozen corn starch paste during storage at temperatures in the range of -5 to -20 °C.

Different formulations were tested in order to obtain a suitable fixative for this method of indirect observation of the ice crystals. A solution of formaldehyde, ethanol and water (10:45:45 V:V) was selected because it minimized substitution-induced distortion and contraction of the matrix. The diffusion coefficients of the selected fixative in the frozen system were measured at different temperatures in conditions of unidirectional mass transfer in a semi …

Morphological Three-Dimensional Analysis, C. Gratin, F. Meyer

Scanning Microscopy

This paper presents the main results of our research on mathematical morphology for three-dimensional images. The first issue is to decide which grid must be used. The face-centred cubic grid and the centred cubic grid seem to be more suitable than the cubic grid in terms of possible rotations. For these two grids we derive the formulae for the basic Minkovski measures. Then we show through several examples that extension from 2D to 3D is straightforward for most transformations. The efficiency of direct 3D processing is illustrated by applications to filtering, overlapping particle separation and grey-scale image segmentation.

Su(3) X Su(2) X U(1)Su(3): The Residual Symmetry Of Conformal Gravity, James Thomas Wheeler

All Physics Faculty Publications

SUe 4) x SU(2) is shown to characterize the possible choices of spacetime metric constructible from the gauge fields of the conformal group. When this symmetry is broken by the choice of metric, exactly the SU(3) x SU(2) x U(l) symmetry of the standard model remains. The conformal group consists of Lorentz transformations, translations, inverse translations and dilations. Treated in the standard way, conformal symmetry fails as a unifying gauge group: dilations make the mass spectrum continuous, and the inverse translational gauge field is auxiliary. The theory reduces back to the Poincare group.

Imaging Deformed Proteins: Characterising The State Fully, W. O. Saxton

Scanning Microscopy

By analysing the positions of individual unit cells in the image of a distorted macromolecular crystal, it is possible to achieve considerably more than is achieved by the correlation averaging or unbending now widely practised. It is possible partly to compensate for individual molecular distortion; and it is possible to identify molecules in equivalent environments (which can be expected to be in equivalent states of strain), selective averaging of which yields images that show how strain is accommodated at the sub-molecular level. The possible presence of surface forces applied to the crystal by its support film complicates the analysis and …

The Watershed Transformation Applied To Image Segmentation, Serge Beucher

Scanning Microscopy

Image segmentation by mathematical morphology is a methodology based upon the notions of watershed and homotopy modification.This paper aims at introducing this methodology through various examples of segmentation in materials sciences, electron microscopy and scene analysis.

First, we defined our basic tool, the watershed transform. We showed that this transformation can be built by implementing a flooding process on a greytone image. This flooding process can be performed by using elementary morphological operations such as geodesic skeleton and reconstruction. Other algorithms are also briefly presented (arrows representation).

Then, the use of this transformation for image segmentation purposes is discussed. The …

Phase Space Methods In Image Formation Theory, Victor Castaño, Gustavo Vásquez-Polo, Ramón Gutiérrez-Castrejón

Scanning Microscopy

A review of the basic mathematical principles and properties of some phase space functions (Wigner and Ambiguity functions) is first presented in a more general mathematical context. Then, we deal in detail with three applications : image formation in optical systems (specifically cascading systems of lenses), image formation in Transmission Electron Microscopy, by taking advantage of some formal similarities with the previous examples and, finally, contrast transfer functions in Electron Microscopy in order to obtain 2-dimensional plots which provide information on the behavior of a transmission electron microscope. Also, the relations of these functions with other mathematical tools utilized in …

Agriculture Irrigation And Water Use, Rajinder S. Bajwa, William M. Crosswhite, John E. Hostetler, Olivia W. Wright, United States Department Of Agriculture, Economic Research Service

All U.S. Government Documents (Utah Regional Depository)

The 17 Western States, plus Arkansas, Florida, and Louisiana, account for 91 percent of all U.S. irrigated acreage, with the Western States alone contributing over 85 percent. This report integrates data on the distribution, characteristics, uses, and management of water resources from a wide variety of data sources. The report includes charts and tables on water use in irrigation; farm data comparing selected characteristics of irrigated and nonirrigated farms; and data on water application systems, sources of water, pump energy expenses by energy type, values of irrigated and nonirrigated land, and cash rents.

Cultural Diversity & Adaptation: The Archaic, Anasazi, & Navajo Occupation Of The Upper San Juan Basin, United States Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

Recent work in the upper San Juan Basin has more than doubled the number of known, as well as excavated, sites. Without exception, this work has modified and expanded long-held views of the PaleoIndian, Archaic, Anasazi, and Navajo people who inhabited the area. The papers presented in this volume reflect these changes and represent the cutting edge of southwestern archaeology.

Statistical Considerations In Rangeland Monitoring, United States Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

This Technical Reference deals with the statistical aspects of rangeland monitoring and is intended to help the BLM range conservationist in planning, analyzing, interpreting, and evaluating monitoring studies. It is not a statistics cookbook and assumes a level of knowledge of statistical analysis comparable to what most college graduates are exposed to during their undergraduate training. The material covered in this Technical Reference is divided into five sections. Chapter 1 highlights the statistical topics required to analyze monitoring data and gives appropriate references. Chapter 2 addresses the underlying statistical issues of rangeland monitoring. Chapters 3 and 4 deal with the …

Tiger Team Assessment Of The Naval Petroleum And Oil Shale Reserves Colorado, Utah, And Wyoming, United States Department Of Energy

All U.S. Government Documents (Utah Regional Depository)

This report documents the Tiger Team Assessment of the Naval Petroleum and Oil Shale Reserves in Colordao, Utah, and Wyoming (NPOSR-CUW). NPOSR-CUW consists of Naval Petroleum Reserve Number 3 (NPR-3) located near Casper, Wyoming; Naval Oil Shale Reserve Number 1 (NOSR-1) and Naval Oil Shale Reserve Number 3 (NOSR-3) located near Rifle, Colorado; and Naval Oil Shale Reserve Number 2 (NOSR-2) located near Vernal, Utah, which was not examined as part of this assessment.

Selected Hydrologic Data For Cache Valley, Utah And Idaho, 1969-91, D. Michael Roark, Karen M. Hanson, U.S. Geological Survey

All U.S. Government Documents (Utah Regional Depository)

This report contains hydrologic data collected in Cache Valley from 1969 to 1991. The report area is in north-central Utah and southeast Idaho, within the Basin and Range physiographic province described by Fenneman (1931), and includes about 660 square miles. Most of the data in this report were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Divisions or Water Resources and Water Rights. Some of the data collected before 1969 were previously published by McGreevy and Bjorklund (1970). The purpose of this report is to provide hydrologic data for use by the general …

Effects Of Seeder Design And Seed Placement On Seedling Size And Cull Rates At Western Forest Nurseries, United States Department Of Agriculture, Forest Service

Forestry

Nursery plots sown with the Summit Precision Seeder and the Oyjord Seeder were compared with plots oversown and hand thinned to desired spacings. We studied 26 seedlots of nine conifer species at five Forest Service, U.S. Department of Agriculture, nurseries. Results varied with nursery, species, and seed characteristics. Thinned plots produced less clumping and fewer gaps between seedlings, but showed little or no difference in seedling size, nor in the number of acceptable seedlings.

A Partial Glossary Of Elk Management Terms, United States Department Of Agriculture, Forest Service

Forestry

This glossary helps define terms that have been misused during forest planning. Terms that were developed from research on the influences of timber sales and roads during the summer months have been used inappropriately when referring to winter range, hunting seasons, and other conditions. The glossary is based on the results of an "Elk Management Terminology Workshop" held at the University of Montana's Lubrecht Experimental Forest on April 3-4, 1990.

Plant Community Diversity After Herbicide Control Of Spotted Knapweed, United States Department Of Agriculture, Forest Service

Herbicides and Pesticides

Herbicides were applied to four west-central Montana sites with light to moderate spotted knapweed (Centaurea maculosa Lam.) infestations. Althought knapweed suppression was high, 2 years after the spraying the communities were not converted to grass monocultures. No large declines in plant diversity were caused by the herbicides, and small depressions were probably transitory. By the third year, diversity had increased.