1,196 research outputs found
Gas generators produce hydrogen-rich fuel
Resulting fuel, which is produced from gasoline and water, can be burned by gasoline engines with significantly reduced pollution and improved fuel economy
Economic Evaluation of Soybean Fungicide Seed Treatments
The effect of nine different fungicide seed treatments for soybeans were tested from 2004 to 2007 at Keiser, Stuttgart, and Hope, Arkansas. While seedling emergence was effective across all treatments, only three treatments showed statistically significant differences in partial returns, defined as gross revenue minus seed and seed treatment costs. Comparisons of the regret a producer would experience as a result of non-optimal seed treatment suggested that broad spectrum seed treatment could enhance profitability by an average of $32 per acre with similar treatment recommendations across a range of seeding rates, output prices and study conditions.Crop Production/Industries, Production Economics,
Koopman Operator and its Approximations for Systems with Symmetries
Nonlinear dynamical systems with symmetries exhibit a rich variety of
behaviors, including complex attractor-basin portraits and enhanced and
suppressed bifurcations. Symmetry arguments provide a way to study these
collective behaviors and to simplify their analysis. The Koopman operator is an
infinite dimensional linear operator that fully captures a system's nonlinear
dynamics through the linear evolution of functions of the state space.
Importantly, in contrast with local linearization, it preserves a system's
global nonlinear features. We demonstrate how the presence of symmetries
affects the Koopman operator structure and its spectral properties. In fact, we
show that symmetry considerations can also simplify finding the Koopman
operator approximations using the extended and kernel dynamic mode
decomposition methods (EDMD and kernel DMD). Specifically, representation
theory allows us to demonstrate that an isotypic component basis induces block
diagonal structure in operator approximations, revealing hidden organization.
Practically, if the data is symmetric, the EDMD and kernel DMD methods can be
modified to give more efficient computation of the Koopman operator
approximation and its eigenvalues, eigenfunctions, and eigenmodes. Rounding out
the development, we discuss the effect of measurement noise
Hydrogen rich gas generator
A process and apparatus is described for producing a hydrogen rich gas by injecting air and hydrocarbon fuel at one end of a cylindrically shaped chamber to form a mixture and igniting the mixture to provide hot combustion gases by partial oxidation of the hydrocarbon fuel. The combustion gases move away from the ignition region to another region where water is injected to be turned into steam by the hot combustion gases. The steam which is formed mixes with the hot gases to yield a uniform hot gas whereby a steam reforming reaction with the hydrocarbon fuel takes place to produce a hydrogen rich gas
Experimental verification of computer spray-combustion models
Analytical model formulation, representing performance of spray-combustion device, is based on understanding of atomization, mixing, vaporization, and combustion which occurs in device. Report lists results of correlations of computed values with values obtained from experiments with rocket combustor. Technique offers excellent method for evaluating validity and ranges of applicability of combustion models
A Physics-Based Approach to Unsupervised Discovery of Coherent Structures in Spatiotemporal Systems
Given that observational and numerical climate data are being produced at
ever more prodigious rates, increasingly sophisticated and automated analysis
techniques have become essential. Deep learning is quickly becoming a standard
approach for such analyses and, while great progress is being made, major
challenges remain. Unlike commercial applications in which deep learning has
led to surprising successes, scientific data is highly complex and typically
unlabeled. Moreover, interpretability and detecting new mechanisms are key to
scientific discovery. To enhance discovery we present a complementary
physics-based, data-driven approach that exploits the causal nature of
spatiotemporal data sets generated by local dynamics (e.g. hydrodynamic flows).
We illustrate how novel patterns and coherent structures can be discovered in
cellular automata and outline the path from them to climate data.Comment: 4 pages, 1 figure;
http://csc.ucdavis.edu/~cmg/compmech/pubs/ci2017_Rupe_et_al.ht
An experimental correlation of the nonreactive properties of injection schemes and combustion effects in a liquid-propellant rocket engine. Part II. Instrumentation, experimental apparatus, and experimental techniques
Apparatus, techniques, and instrumentation for experimental correlation of nonreactive injection schemes and combustion effects in liquid propellant rocket engin
Hydrogen rich gas generator
A process and apparatus is described for producing a hydrogen rich gas from liquid hydrocarbons and water by means of the steam reforming process using a partial oxidation approach
On the evolution of advanced propulsion systems for spacecraft
Use of earth-storable propellants in unmanned spacecraft propulsion systems for flights to near planets and moo
Chirale Lactole, IV. Selektivitäten bei Acetalisierungsreaktionen enantiomerenreiner Lactole am Beispiel von Octahydro-8,9,9-trimethyl-5,8-methano-2H-1-benzopyran-2-ol
Eine Synthese für das Lactol 1 wird beschrieben und seine Eignung als Reagens zur Racemattrennung an einigen Beispielen gezeigt. Aufgrund einer Röntgenstruktur und konformationsanalytischer Überlegungen wird eine allgemeine Regel erarbeitet, nach welcher die Absolutkonfiguration acyclischer Alkyl-aryl-carbinole aus dem Verlauf der Acetalisierungsreaktion eines enantiomerenreinen Lactols mit dem racemischen Alkohol vorhergesagt werden kann
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