Numerical calculations of the steady-state, wind-driven currents in Lake Erie

Mathematical model for calculating steady-state, wind-driven currents in Lake Eri

Ecuaciones de diferencias mejoradas para ecuaciones diferenciales

Se presenta en este artículo una resena sobre el uso del método integral para derivar ecuaciones de diferencias a partir de ecuaciones diferenciales. El método se aplica a varios tipos de ecuaciones diferenciales ordinarias correspondientes a problemas de valores de contorno y a problemas de valores iniciales, ilustrándose la utilidad del método con varios ejemplos sencillos.Peer Reviewe

Numerical calculations of the wind driven currents in Lake Erie and comparison with measurements

Numerical analysis of steady state, wind driven currents in Lake Erie, using shallow lake mode

Early = Earliest?

Early query answering is the core issue of memory efficient query evaluation on data streams. The idea is to select and reject answer candidates as early as possible on the stream, so that they do not have to be stored in main memory. Since earliest query answering is unfeasible for XPath, as first no- ticed by Benedikt, Jeffrey and Ley-Wild in 2008, most exist- ing streaming algorithms for XPath approximate it in some early manner, while focussing on high time efficiency. Such approximations, however, spoil all theoretical guarantees on memory efficiency. In this paper, we prove that earliest query answering is indeed feasible for positive Forward XPath queries, which have neither unsatisfiable nor valid subqueries. The core in- sight is that a variant of Colmerauer's independence property can be proven for the corresponding fragment of the FXP tree logic. Based on this independence property, we can show that the early query answering algorithm from [13], which is based on a compiler from FXP to early nested word automata, is indeed earliest for all positive FXP0 queries with neither unsatisfiable nor valid subformulas. Further- more, this algorithm outperforms most previous algorithms for XPath evaluation on XML streams in time efficiency and coverage, as shown elsewhere. Available here.</p

Synthesis of MnFeO3 from the oxidate thermal decomposition of Mn(Fe(CN)5NO)*2H2O

On the basis of previous studies about the pentacyanonitrosylmetallates whose thermal decomposition generates different type of oxides, the Mn[Fe(CN)5NO]·2H2O was used as raw material to give FeMnO3. The decomposition was studied by Thermogravimetric (TGA-DTG) and Differential Thermal Analysis (DTA) under air atmosphere, between room temperature and 1200°C. IR spectroscopy and XRPD, refined by Rietveld analysis, were used to follow the process. The XRPD of the sample heated at different temperatures showed the following sequence: MnFe2O4 and (Mn,Fe)2O3 disordered bixbyte phases, until arriving to the final product, MnFeO3. Temperature programmed reduction (TPR) and EDS-EDAX analyses were used for the characterization, as well.En base a estudios previos sobre pentacianonitrosilmetalatos, cuya descomposición térmica genera diferentes tipos de óxidos, el compuesto Mn[Fe(CN)5NO]·2H2O fue elegido como materia prima para dar FeMnO3. La descomposición en atmósfera de aire, fue seguida por Análisis Termogravimétrico (TG-DTG) y Térmico Diferencial (ATD) hasta 1200ºC. Los productos en cada etapa de la descomposición, fueron caracterizados por Espectroscopia Infrarroja (FTIR) y Difracción de Rayos X (DRX) empleando el Método de Rietveld para el ajuste de los datos. El seguimiento por DRX en polvo, a diferentes temperaturas muestra los siguientes productos: MnFe2O4 y (Mn,Fe)2O3 (desordenada), hasta llegar a MnFeO3 como único producto final. Para la caracterización de estas fases se utilizaron además, las técnicas de Reducción a temperatura programada (TPR) y espectroscopía de emisión de rayos X (EDS).Fil: Lick, Ileana Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Soria, Delia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; Argentin

Co-Rh modified natural zeolites as new catalytic materials to oxidize propane and naphthalene from emission sources

Natural zeolites as a raw material to prepare catalytic precursors for the oxidation reaction of linear and poly-aromatic hydrocarbons are reported in this work. The process consisted in the formation of mono- and bi-metallic species containing Co and Co-Rh on natural zeolite tuffs. The materials are analyzed by different physicochemical techniques and used as catalysts for propane and naphthalene oxidation in emissions sources. Comparatively, Rh-zeolites are the most active catalysts for propane conversion. In this case, the formation of mixed oxides seems to be conditioned by surface properties. It could also be suggested that the Rh incorporation on a non-active phase in bimetallic catalysts impacts the effectiveness of the system. In addition, the NO presence increases the activity of bimetallic materials. Rh-Co zeolite systems markedly influence the naphthalene combustion temperature. Whereas in the absence of a catalyst a conversion rate of 50% and 100% is reached at 430 C and 485 °C, respectively. It is interesting to observe that for RhCoCli-Mor and RhCoCli catalyst the 100% conversion is reached at 250 °C.Fil: Leguizamón Aparicio, María Silvia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Canafoglia, Maria Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Ocsachoque, Marco Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Lick, Ileana Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Botto, Irma Lia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica ; Argentin

Drawing Planar Graphs with Few Geometric Primitives

We define the \emph{visual complexity} of a plane graph drawing to be the number of basic geometric objects needed to represent all its edges. In particular, one object may represent multiple edges (e.g., one needs only one line segment to draw a path with an arbitrary number of edges). Let $n$ denote the number of vertices of a graph. We show that trees can be drawn with $3n/4$ straight-line segments on a polynomial grid, and with $n/2$ straight-line segments on a quasi-polynomial grid. Further, we present an algorithm for drawing planar 3-trees with $(8n-17)/3$ segments on an $O(n)\times O(n^2)$ grid. This algorithm can also be used with a small modification to draw maximal outerplanar graphs with $3n/2$ edges on an $O(n)\times O(n^2)$ grid. We also study the problem of drawing maximal planar graphs with circular arcs and provide an algorithm to draw such graphs using only $(5n - 11)/3$ arcs. This is significantly smaller than the lower bound of $2n$ for line segments for a nontrivial graph class.Comment: Appeared at Proc. 43rd International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2017

Reverse-correlating mental representations of sex-typed bodies: the effect of number of trials on image quality

Sex categorization is a critical process in social perception. While psychologists have long theorized that perceivers have distinct mental representations of men and women that help them to achieve efficient sex categorizations, researchers have only recently begun using reverse-correlation to visualize the content of these mental representations. The present research addresses two issues concerning this relatively new methodological tool. First, previous studies of reverse-correlation have focused almost exclusively on perceivers' mental representations of faces. Our study demonstrates that this technique can also be used to visualize mental representations of sex-typed bodies. Second, most studies of reverse-correlation have employed a relatively large number of trials (1000+) to capture perceivers' mental representations of a given category. Our study demonstrated that, at least for sex-typed representations of bodies, high quality reverse-correlation images can be obtained with as few as 100 trials. Overall, our findings enhance knowledge of reverse-correlation methodology in general and sex categorization in particular, providing new information for researchers interested in using this technique to understand the complex processes underlying social perception

Larval nematodes in stomach wall granulomas of smelt Osmerus eperlanus from the German North Sea coast

Occurrence of stomach wall granulomas in European smelt was studled at 6 locations along the German North Sea coast. Identification of larval nematodes inhabiting these granulomas is provided for the first time. Three species, isolated by pepsin-HC1 digestion, are involved: Hysterothylacium cf. cornutum, Cosmocephalus obvelatus and Paracuaria tridentata. 72% of all stomachs examined were affected. The ratio of number of granulomas to number of the 3 larval species free in the mesentery was 1:1.3. Differences in prevalences and intensities were significant among all locations. Granuloma abundance was highest in samples from the Elbe estuary decreasing in the other locations relative to their distance from the Elbe. There was no relationship between the number of larvae encapsulated on the stomach wall and the number of larval P decipjens in the musculature (r = 0.3). Host condition factor could not be related to number of granulomas. Smelt appaears to be an important transmitter of spiruroid nematode larvae to marine birds in this region