Data communication between data terminal equipment and the JPL administrative data base management system

Approaches to enabling an installed base of mixed data terminal equipment to access a data base management system designed to work with a specific terminal are discussed. The approach taken by the Jet Propulsion Laboratory is described. Background information on the Jet Propulsion Laboratory (JPL), its organization and a description of the Administrative Data Base Management System is included

Ring-shear studies of till deformation: Coulomb-plastic behavior and distributed strain in glacier beds

A ring-shear device was used to study the factors that control the ultimate(steady) strength of till at high shear strains.Tests at a steady strain rate and at different stresses normal to the shearing direction yielded ultimate friction angles of 26.3° and 18.6° for tills containing 4% and 30% clay-sized particles, respectively Other tests at steady normal stresses and variable shear-strain rates indicated a tendency for both tills to weaken slightly with increasing strain rate. This weakening may be due to small increases in till porosity.These results provide no evidence of viscous behavior and suggest that a Coulomb-plastic idealization is reasonable for till deformation. However, viscous behavior has often been suggested on the basis of distributed shear strain observed in subglacial till. We hypothesize that deformation may become distributed in till that is deformed cyclically in response to fluctuations in basal water pressure. During a deformation event, transient dilation of discrete shear zones should cause a reduction in internal pore-water pressure that should strengthen these zones relative to the surrounding till, a process called dilatant hardening. Consequent changes in shear-zone position, when integrated over time, may yield the observed distributed strain

Frames over finite fields: Equiangular lines in orthogonal geometry

We investigate equiangular lines in finite orthogonal geometries, focusing specifically on equiangular tight frames (ETFs). In parallel with the known correspondence between real ETFs and strongly regular graphs (SRGs) that satisfy certain parameter constraints, we prove that ETFs in finite orthogonal geometries are closely aligned with a modular generalization of SRGs. The constraints in our finite field setting are weaker, and all but~18 known SRG parameters on $v \leq 1300$ vertices satisfy at least one of them. Applying our results to triangular graphs, we deduce that Gerzon's bound is attained in finite orthogonal geometries of infinitely many dimensions. We also demonstrate connections with real ETFs, and derive necessary conditions for ETFs in finite orthogonal geometries. As an application, we show that Gerzon's bound cannot be attained in a finite orthogonal geometry of dimension~5

Frames over finite fields: Equiangular lines in orthogonal geometry

We investigate equiangular lines in finite orthogonal geometries, focusing specifically on equiangular tight frames (ETFs). In parallel with the known correspondence between real ETFs and strongly regular graphs (SRGs) that satisfy certain parameter constraints, we prove that ETFs in finite orthogonal geometries are closely aligned with a modular generalization of SRGs. The constraints in our finite field setting are weaker, and all but~18 known SRG parameters on $v \leq 1300$ vertices satisfy at least one of them. Applying our results to triangular graphs, we deduce that Gerzon's bound is attained in finite orthogonal geometries of infinitely many dimensions. We also demonstrate connections with real ETFs, and derive necessary conditions for ETFs in finite orthogonal geometries. As an application, we show that Gerzon's bound cannot be attained in a finite orthogonal geometry of dimension~5

Avalanche Dynamics in Wet Granular Materials

We have studied the dynamics of avalanching wet granular media in a rotating drum apparatus. Quantitative measurements of the flow velocity and the granular flux during avalanches allow us to characterize novel avalanche types unique to wet media. We also explore the details of viscoplastic flow (observed at the highest liquid contents) in which there are lasting contacts during flow, leading to coherence across the entire sample. This coherence leads to a velocity independent flow depth at high rotation rates and novel robust pattern formation in the granular surface.Comment: 5 pages, 3 figures in color, REVTeX4, for smaller pdfs see http://angel.elte.hu/~tegzes/condmat.htm

Oxidized flavors in strawberry ice cream

At the time this project was initiated only a small amount of material had been published concerning this defect and even that was subject to considerable controversy. That the defect under consideration is important has been emphasized by other workers and needs no reiteration here. It was the opinion of the authors that the study should be made with ice cream manufactured in a commercial manner and from commercial products. This was done wherever possible. The objectives of the project were to attempt to determine which single factor or group of the following possible factors-oxidases in the fruit, copper and iron in the mix, strawberries and types of added solids - was responsible for the occurrence of the defect. It was likewise considered advisable to see whether or not such changes as occur in the fat, if the defect were a fat oxidation, were sufficient to cause detectable variations in the iodine, acetyl and Reichert- Meissl numbers of the fat of the ice cream

Results on Plasma Focusing of High Energy Density Electron and Positron Beams

We present results from the SLAC E-150 experiment on plasma focusing of high energy density electron and, for the first time, positron beams. We also discuss measurements on plasma lens-induced synchrotron radiation, longitudinal dynamics of plasma focusing, and laser- and beam-plasma interactions.Comment: LINAC 2000 paper No. THC13, Monterey, CA. Aug.21-25,2000, 3 pages, 2 figure

Improving undergraduate STEM education: The efficacy of discipline-based professional development

We sought to determine whether instructional practices used by undergraduate faculty in the geosciences have shifted from traditional teacher-centered lecture toward student-engaged teaching practices and to evaluate whether the national professional development program On the Cutting Edge (hereinafter Cutting Edge) has been a contributing factor in this change. We surveyed geoscience faculty across the United States in 2004, 2009, and 2012 and asked about teaching practices as well as levels of engagement in education research, scientific research, and professional development related to teaching. We tested these self-reported survey results with direct observations of teaching using the Reformed Teaching Observation Protocol, and we conducted interviews to understand what aspects of Cutting Edge have supported change. Survey data show that teaching strategies involving active learning have become more common, that these practices are concentrated in faculty who invest in learning about teaching, and that faculty investment in learning about teaching has increased. Regression analysis shows that, after controlling for other key influences, faculty who have participated in Cutting Edge programs and who regularly use resources on the Cutting Edge website are statistically more likely to use active learning teaching strategies. Cutting Edge participants also report that learning about teaching, the availability of teaching resources, and interactions with peers have supported changes in their teaching practice. Our data suggest that even one-time participation in a workshop with peers can lead to improved teaching by supporting a combination of affective and cognitive learning outcomes

Nutrition and its role in human evolution

Peer reviewedPostprin