1,845 research outputs found
Self-Referential Noise as a Fundamental Aspect of Reality
Noise is often used in the study of open systems, such as in classical
Brownian motion and in Quantum Dynamics, to model the influence of the
environment. However generalising results from G\"{o}del and Chaitin in
mathematics suggests that systems that are sufficiently rich that
self-referencing is possible contain intrinsic randomness. We argue that this
is relevant to modelling the universe, even though it is by definition a closed
system. We show how a three-dimensional process-space may arise, as a Prigogine
dissipative structure, from a non-geometric order-disorder model driven by,
what is termed, self-referential noise.Comment: 7 pages, Latex, 3 ps figures. Contribution to the 2nd International
Conference on Unsolved Problems of Noise, Adelaide 199
AC impedance analysis of polypyrrole thin films
The AC impedance spectra of thin polypyrrole films were obtained at open circuit potentials from -0.4 to 0.4 V vs SCE. Two limiting cases are discussed for which simplified equivalent circuits are applicable. At very positive potentials, the predominantly nonfaradaic AC impedance of polypyrrole is very similar to that observed previously for finite porous metallic films. Modeling of the data with the appropriate equivalent circuit permits effective pore diameter and pore number densities of the oxidized film to be estimated. At potentials from -0.4 to -0.3 V, the polypyrrole film is essentially nonelectronically conductive and diffusion of polymer oxidized sites with their associated counterions can be assumed to be linear from the film/substrate electrode interface. The equivalent circuit for the polypyrrole film at these potentials is that previously described for metal oxide, lithium intercalation thin films. Using this model, counterion diffusion coefficients are determined for both semi-infinite and finite diffusion domains. In addition, the limiting low frequency resistance and capacitance of the polypyrrole thin fims was determined and compared to that obtained previously for thicker films of the polymer. The origin of the observed potential dependence of these low frequency circuit components is discussed
Control of critical coupling in a ring resonator fiber configuration: application to wavelength-selective switching, modulation, amplification, and oscillation
By controlling the internal loss of a ring resonator near critical coupling, we demonstrate control of the transmitted power in a fiber that is coupled to the resonator. We also demonstrate wavelength-selective optical amplification and oscillation
Defining, Practicing, and Assessing Innovation by Minnesota’s Local Government
The purpose of the study was to examine, summarize, and categorize how leaders of select cities, counties, and school districts (kindergarten through 12th grade) in Minnesota define, practice, and assess innovation.
The significance of the study was two-fold: 1) the findings may add to the body of research regarding innovation in local government, and 2) may contribute to the understanding of innovations by local government officials.
The study engaged 81 local units of government (i.e., cities, counties and school districts – kindergarten through 12th grade) in the State of Minnesota via electronic survey. Of the 81 local units of government engaged 35 participated, which represented 26 cities, 2 counties, and 7 school districts.
The study and survey tool was designed in three parts comprised of: 1) Survey Participant Profile, 2) Innovation Practices and Types, and 3) Innovation Assessment Practices and Types.
The study contributes to the current body of research knowledge by providing new research on the defining, practice, and assessment of innovation within local units of government. The study ultimately may offer government leaders useable and valuable information about innovation in local government so that it may survive and thrive
Some physical properties and cation exchange capacities of soils from greens of four golf courses as compared to USGA Green section specifications
The purpose of this investigation was to determine and compare certain physical properties and cation exchange capacities at various depths of putting green soils from four golf courses in the Knoxville, Tennessee area. These golf courses were of different ages and types of green construction. This study also included a comparison of these same physical properties and CEC with a laboratory soil mixture of sand, silt, clay and organic matter prepared in accordance with USGA Green Section specifications which served as a standard of known and currently accepted soil property responses. The experimental data for this investigation were obtained by laboratory analysis of particle size distribution, organic matter con-tent, bulk density, aeration porosity, total porosity, percolation rates, available moisture holding capacity and cation exchange capacity. It was found that based on particle size distribution only Cobbly Nob golf course green soils were similar to the USGA standard. Fox Den golf course, although built with the aid of the USGA laboratory recom-mendations on components for putting green soil mixture, had putting green soils similar to those found in greens on Deane Hill and Cherokee golf course greens which were built without the aid of USGA laboratory recommendations. These three golf courses had putting green soils with much greater amounts of silt and clay and less total sand than the USGA standard or Cobbly Nob putting green soils. It was found that in the older greens on Deane Hill and Cherokee golf courses fine and very fine sand, silt and clay increased with increasing depth. Furthermore, the top few cm of all putting green soils were somewhat different to soil taken from lower depths, indicat-ing the use of different textured topdressing materials. Organic matter content tended to increase in the upper soil levels in all greens and with the greatest increase in the older greens. The USGA standard mixture was exceeded in organic matter content by the upper levels of the oldest greens only. Variations in particle size distribution and organic matter content among the soil samples were reflected in variations in aeration porosity, total porosity, percolation rate, available moisture holding capacity and CEC. It was found in this study that bulk density was not signifi-cantly different among soil samples. Aeration porosities, total porosities and percolation rates generally decreased as fine and very fine sand, silt and clay increased. The USGA standard and Cobbly Nob putting green soils were within accept-able ranges of aeration porosity, total porosity and percolation rate while all others were considerably lower. Available moisture holding capacity increased as amounts of organic matter, fine and very fine sand, silt and clay increased, however increases in organic matter caused the greatest increase. Cation exchange capacity increased as both clay and organic matter content increased although increases in organic matter resulted in the greatest increase
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