343 research outputs found
TRADE AGREEMENTS, COMPETITION, AND THE ENVIRONMENT: GRIDLOCK AT THE CROSSROADS
Environmental Economics and Policy, International Relations/Trade,
Antigone
Thesis (M.A.)--Boston University
Bibliography at end of Section II
Antigone
Thesis (M.A.)--Boston University
Bibliography at end of Section II
Observations on Economic Adulteration of High-Value Food Products: The Honey Case
The paper highlights the issue of economic adulteration of high-value food products and provides a context for discussion and analysis based on experiences with the U.S. honey industry. Perspectives on economic adulteration are identified, trends relevant to the issue of economic adulteration are discussed, and industry opinions on economic adulteration of honey are summarized. The paper is based on research funded by the National Honey Board to provide a platform for industry dialogue on the need for a quality-assurance program.Agribusiness,
Quadratic metric-affine gravity
We consider spacetime to be a connected real 4-manifold equipped with a
Lorentzian metric and an affine connection. The 10 independent components of
the (symmetric) metric tensor and the 64 connection coefficients are the
unknowns of our theory. We introduce an action which is quadratic in curvature
and study the resulting system of Euler-Lagrange equations. In the first part
of the paper we look for Riemannian solutions, i.e. solutions whose connection
is Levi-Civita. We find two classes of Riemannian solutions: 1) Einstein
spaces, and 2) spacetimes with metric of a pp-wave and parallel Ricci
curvature. We prove that for a generic quadratic action these are the only
Riemannian solutions. In the second part of the paper we look for
non-Riemannian solutions. We define the notion of a "Weyl pseudoinstanton"
(metric compatible spacetime whose curvature is purely Weyl) and prove that a
Weyl pseudoinstanton is a solution of our field equations. Using the
pseudoinstanton approach we construct explicitly a non-Riemannian solution
which is a wave of torsion in Minkowski space. We discuss the possibility of
using this non-Riemannian solution as a mathematical model for the graviton or
the neutrino.Comment: 25 pages, LaTeX2
Theology, News and Notes - Vol. 20, No. 04
Theology News & Notes was a theological journal published by Fuller Theological Seminary from 1954 through 2014.https://digitalcommons.fuller.edu/tnn/1048/thumbnail.jp
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ADVANCED TECHNOLOGIES FOR STRIPPER GAS WELL ENHANCEMENT
As part of Task 1 in the Advanced Technologies for Stripper Gas Well Enhancement, Schlumberger--Holditch Reservoir Technologies (H-RT) has partnered with two Appalachian Basin producers, Great Lakes Energy (formerly Range Resources) and Belden and Blake Corporation, to develop methodologies for the identification and enhancement of stripper wells with economic upside potential. These industry partners have provided data for over 700 wells in northwestern Pennsylvania. Phase 1 goals of this project are to develop and validate methodologies that can quickly and cost-effectively identify wells with enhancement potential. We are currently in the final stages of developing and testing our new Access/Excel based software and processing this well data to generate a list of potential candidate wells that can be used in Phase 2 to validate these methodologies
Modeling Micro-porous Surfaces for Secondary Electron Emission Control to Suppress Multipactor
This work seeks to understand how the topography of a surface can be engineered to control secondary electron emission (SEE) for multipactor suppression. Two unique, semi-empirical models for the secondary electron yield (SEY) of a micro-porous surface are derived and compared. The first model is based on a two-dimensional (2D) pore geometry. The second model is based on a three-dimensional (3D) pore geometry. The SEY of both models is shown to depend on two categories of surface parameters: chemistry and topography. An important parameter in these models is the probability of electron emissions to escape the surface pores. This probability is shown by both models to depend exclusively on the aspect ratio of the pore (the ratio of the pore height to the pore diameter). The increased accuracy of the 3D model (compared to the 2D model) results in lower electron escape probabilities with the greatest reductions occurring for aspect ratios less than two. In order to validate these models, a variety of micro-porous gold surfaces were designed and fabricated using photolithography and electroplating processes. The use of an additive metal-deposition process (instead of the more commonly used subtractive metal-etch process) provided geometrically ideal pores which were necessary to accurately assess the 2D and 3D models. Comparison of the experimentally measured SEY data with model predictions from both the 2D and 3D models illustrates the improved accuracy of the 3D model. For a micro-porous gold surface consisting of pores with aspect ratios of two and a 50% pore density, the 3D model predicts that the maximum total SEY will be one. This provides optimal engineered surface design objectives to pursue for multipactor suppression using gold surfaces. © 2017 Author(s)
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