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Limit Set (limit + set)
Selected AbstractsAsymmetric Abstraction and Allocation: The Israeli-Palestinian Water Pumping RecordGROUND WATER, Issue 1 2009Mark Zeitoun The increased attention given to international transboundary aquifers may be nowhere more pressing than on the western bank of the Jordan River. Hydropolitical analysis of six decades of Israeli and Palestinian pumping records reveals how ground water abstraction rates are as asymmetrical as are water allocations. The particular hydrogeology of the region, notably the variability in depth to ground water, variations in ground water quality, and the vulnerability of the aquifer, also affect the outcome. The records confirm previously drawn conclusions of the influence of the agricultural lobby in maintaining a supply-side water management paradigm. Comparison of water consumption rates divulges that water consumed by all sectors of the farming-based Palestinian economy is less than half of Israeli domestic consumption. The overwhelming majority of "reserve" flows from wet years are sold at subsidized rates to the Israeli agricultural sector, while very minor amounts are sold at normal rates to the Palestinian side for drinking water. An apparent coevolution of water resource variability and politics serves to explain increased Israeli pumping prior to negotiations in the early 1990s. The abstraction record from the Western Aquifer Basin discloses that the effective limit set by the terms of the 1995 Oslo II Agreement is regularly violated by the Israeli side, thereby putting the aquifer at risk. The picture that emerges is one of a transboundary water regime that is much more exploitative than cooperative and that risks spoiling the resource as it poisons international relations. [source] The steady states and convergence to equilibria for a 1-D chemotaxis model with volume-filling effectMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 1 2010Yanyan Zhang Abstract We consider a chemotaxis model with volume-filling effect introduced by Hillen and Painter. They also proved the existence of global solutions for a compact Riemannian manifold without boundary. Moreover, the existence of a global attractor in W1, p(,,,n), p>n, p,2, was proved by Wrzosek. He also proved that the ,-limit set consists of regular stationary solutions. In this paper, we prove that the 1-D stationary problem has at most an infinitely countable number of regular solutions. Furthermore, we show that as t,, the solution of the 1-D evolution problem converges to an equilibrium in W1, p, p,2. Copyright © 2009 John Wiley & Sons, Ltd. [source] Asymptotic convergence of p -Laplace equationswith constraint as p tends to 1MATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 9 2002Ken Shirakawa In this paper we treat the Euler,Lagrange equation of a functional including the p -Laplacian for 1 Limits of zeros of orthogonal polynomials on the circleMATHEMATISCHE NACHRICHTEN, Issue 12-13 2005Barry Simon Abstract We prove that there is a universal measure on the unit circle such that any probability measure on the unit disk is the limit distribution of some subsequence of the corresponding orthogonal polynomials. This follows from an extension of a result of Alfaro and Vigil (which answered a question of P. Turán): namely, for n < N , one can freely prescribe the n -th polynomial and N , n zeros of the N -th one. We shall also describe all possible limit sets of zeros within the unit disk. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Possible Environmental Factors Underlying Amphibian Decline in Eastern Puerto Rico: Analysis of U.S. Government Data ArchivesCONSERVATION BIOLOGY, Issue 4 2001Robert F. Stallard I examined changes in environmental conditions by examining time-series data sets that extend back at least into the 1980s, a period when frog populations were declining. The data include forest cover; annual mean, minimum, and maximum daily temperature; annual rainfall; rain and stream chemistry; and atmospheric-dust transport. I examined satellite imagery and air-chemistry samples from a single National Aeronautics and Space Administration aircraft flight across the Caribbean showing patches of pollutants, described as thin sheets or lenses, in the lower troposphere. The main source of these pollutants appeared to be fires from land clearing and deforestation, primarily in Africa. Some pollutant concentrations were high and, in the case of ozone, approached health limits set for urban air. Urban pollution impinging on Puerto Rico, dust generation from Africa ( potential soil pathogens), and tropical forest burning ( gaseous pollutants) have all increased during the last three decades, overlapping the timing of amphibian declines in eastern Puerto Rico. None of the data sets pointed directly to changes so extreme that they might be considered a direct lethal cause of amphibian declines in Puerto Rico. More experimental research is required to link any of these environmental factors to this problem. Resumen: Las pasadas tres décadas han visto grandes disminuciones poblacionales de especies de anfibios en altas elevaciones de Puerto Rico oriental, una región única en los trópicos húmedos debido al grado de monitoreo ambiental que se ha llevado a cabo mediante los esfuerzos de las agencias de gobierno de los Estados Unidos. Examiné los cambios en condiciones ambientales mediante el análisis de datos de series de tiempo que se extienden hasta los 1980s, un periodo en el que las poblaciones de ranas estaban declinando. Los datos incluyen cobertura forestal; temperatura diaria media, mínima y máxima anual; precipitación anual; química de la lluvia y arroyos; y el transporte atmosférico de polvo. Examiné imágenes de satélite y muestras de química del aire obtenidos de un solo vuelo de una nave de la NASA a lo largo del Caribe que mostraba parches de contaminantes descritas como capas delgadas de lentes en la inferior troposfera. La mayor fuente de contaminantes parece ser los incendios de tierras clareadas y la deforestación, principalmente en África. Algunas concentraciones de contaminantes fueron altas y en el caso del ozono, se aproximó a los límites de salud establecidos para aire urbano. La contaminación urbana afectando a Puerto Rico, la generación de polvo en África ( patógenos del suelo potenciales) y la quema de bosque tropical (contaminantes gaseosos) han incrementado durante las últimas tres décadas, superponiéndose con el periodo en que oturrieron las disminuciones de anfibios en Puerto Rico oriental. Ninguno de estos conjuntos de datos señaló directamente hacia cambios tan extremos que debieran ser considerados como una causa letal directa de las disminuciones en Puerto Rico. Se requiere de más investigación experimental que vincule a estos factores ambientales con este problema. [source] One class classifiers for process monitoring illustrated by the application to online HPLC of a continuous processJOURNAL OF CHEMOMETRICS, Issue 3-4 2010Sila Kittiwachana Abstract In process monitoring, a representative out-of-control class of samples cannot be generated. Here, it is assumed that it is possible to obtain a representative subset of samples from a single ,in-control class' and one class classifiers namely Q and D statistics (respectively the residual distance to the disjoint PC model and the Mahalanobis distance to the centre of the QDA model in the projected PC space), as well as support vector domain description (SVDD) are applied to disjoint PC models of the normal operating conditions (NOC) region, to categorise whether the process is in-control or out-of-control. To define the NOC region, the cumulative relative standard deviation (CRSD) and a test of multivariate normality are described and used as joint criteria. These calculations were based on the application of window principal components analysis (WPCA) which can be used to define a NOC region. The D and Q statistics and SVDD models were calculated for the NOC region and percentage predictive ability (%PA), percentage model stability (%MS) and percentage correctly classified (%CC) obtained to determine the quality of models from 100 training/test set splits. Q, D and SVDD control charts were obtained, and 90% confidence limits set up based on multivariate normality (D and Q) or SVDD D value (which does not require assumptions of normality). We introduce a method for finding an optimal radial basis function for the SVDD model and two new indices of percentage classification index (%CI) and percentage predictive index (%PI) for non-NOC samples are also defined. The methods in this paper are exemplified by a continuous process studied over 105.11,h using online HPLC. Copyright © 2010 John Wiley & Sons, Ltd. [source]
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