914 research outputs found
Real Time Leak Isolation in Pipelines Based on a Time Delay Neural Network
In this paper, the one leak isolation problem in a water pipeline is tackled using a Time Delay Neural Network. This scheme comes as an alternative to achieve better computing performance since the classical model-based methods usually have high workloads due to the pipe mathematical model complexity compared with the leak dynamics speed. The Neural Network structure could have better time performance exploiting the parallel architecture of some electronics devices like an FPGA. The authors propose a scheme where, due to the difficulty in obtaining training data from a real pipeline, a mathematical model is used to generate synthetic training data. Such training data is obtained using different leak magnitudes and leak positions and it is also corrupted by random noise in order to emulate real data pipe. Finally, to show the potentiality of this method, some results are presented by using real-noisy databases coming from a pipeline prototype.Following the classical leak diagnosis hypothesis, only flow and pressure sensor at both ends of the aqueducts are used for the treatment.ITESO, A.C
Food Relocation Behavior, Nests, and Brood Balls of Canthon quinquemaculatus Laporte de Castelnau (Coleoptera: Scarabaeidae: Scarabaeinae)
Individuals of Canthon quinquemaculatus Laporte de Castelnau rolled balls up to 4 m from the food source. Stealing balls was common. Male headstand position was observed at the entrance of chambers containing a rolled ball and a female. Nests were shallow, telecoprid, and compound. Male and female cooperate, and parental care is performed (Nesting Pattern V). A total of 23 brood balls from five nesting chambers were obtained from terraria. The brood balls display a protuberance that is separated from the provision chamber by a partition of soil material. An egg chamber that lacks an organic lining is located at the base of the protuberance. At the roof of the egg chamber, there is an aeration conduit that ends in a filter composed of loose soil. The carrion provisions contain a high percentage of soil material. Some brood balls have larval fecal pellets in the external surface of the wall. Egg chamber separated from provisions, lack of an organic lining coating the egg chambers, ejection of larval fecal pellets, and loose soil filters are typical characters of brood balls made by necrophagous Scarabaeinae. The first three characters might reflect a set of adaptive characters of the necrophagous species to their food. These characters might be useful to distinguish fossil brood balls constructed by necrophagous Scarabaeinae from those constructed by coprophagous species.Fil: Cantil, Liliana Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Sánchez, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Dinghi, Pablo Adrián. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Grupo de Investigación en Filogeografía y Filogenias Moleculares; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Genise, Jorge Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin
Cyclopentadienyl yttrium complexes with the [{Ti(η5-C5Me5)(μ-NH)}3(μ3-N)] metalloligand
The reactivity of the yttrium trichloride complex [Cl3Y{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] (2) with a variety of main-group metal cyclopentadienyl reagents [M(C5H3R1R2)] (M = Li, Na, K, Tl) or [Mg(C5H5)2] has been investigated. Treatment of 2 with one equivalent of [Na(C5H5)] or [K(C5H4SiMe3)] gives the monocyclopentadienyl derivatives [(η5-C5H4R)Cl2Y{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] (R = H (3), SiMe3 (4)). Analogous reaction of 2 with lithium [Li(C5H3R1R2)] or thallium [Tl(C5H5)] reagents (1 or 2 equivalents) leads to complexes [(η5-C5H3R1R2)2Y(μ-Cl)2M{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] (M = Li, R1 = R2 = H (5), R1 = H, R2 = SiMe3 (6), R1 = R2 = SiMe3 (7); M = Tl, R1 = R2 = H (8)). Complex 2 reacts with [Mg(C5H5)2] to yield the ionic compound [(μ-Cl)3Mg2{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}2][{Y(η5-C5H5)2Cl}2(μ-Cl)] (9). In contrast to the metathesis of chloride ligands, the reaction of 2 with the lithium indenyl derivative [Li(C9H7)] at room temperature produces C9H8 and the precipitation of [Li(μ-Cl)3Y{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] (10). Crystallization of 10 in pyridine affords the lithium-free [Cl2(py)2Y{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] (11) complex. The X-ray crystal structures of 6 and 11 have been determined.Ministerio de Economía y Competitividad de España, Universidad de Alcal
Automated Readability Assessment for Spanish e-Government Information
This paper automatically evaluates the readability of Spanish e-government websites. Specifically, the websites
collected explain e-government administrative procedures. The evaluation is carried out through the analysis of
different linguistic characteristics that are presumably associated with a better understanding of these resources.
To this end, texts from websites outside the government websites have been collected. These texts clarify the
procedures published on the Spanish Government"s websites. These websites constitute the part of the corpus
considered as the set of easy documents. The rest of the corpus has been completed with counterpart documents
from government websites. The text of the documents has been processed, and the difficulty is evaluated through
different classic readability metrics. At a later stage, automatic learning methods are used to apply algorithms to
predict the difficulty of the text. The results of the study show that government web pages show high values for
comprehension difficulty. This work proposes a new Spanish-language corpus of official e-government websites.
In addition, a large number of combined linguistic attributes are applied, which improve the identification of the
level of comprehensibility of a text with respect to classic metrics.Work supported by the Spanish Ministry of Economy, Industry and Competitiveness, (CSO2017-86747-R)
Successive Protonation and Methylation of Bridging Imido and Nitrido Ligands at Titanium Complexes
The reactions of nitrido complexes [{Ti(eta5-C5Me5)(mu-NH)}3(mu3-N)] (1) and [{Ti(eta5-C5Me5)}4(mu3-N)4] (2) with electrophilic reagents ROTf (R = H, Me; OTf = OSO2CF3) in different molar ratios have allowed the structural characterization of a series of titanium intermediates en route to the formation of the ammonium salts [NR4]OTf and [NR4][Ti(eta5-C5Me5)(OTf)4]. The treatment of the trinuclear imido-nitrido complex 1 with 5.5 equiv of triflic acid in toluene at room temperature led to the dinuclear complex [Ti2(eta5-C5Me5)2(mu-N)(NH3)(mu-O2SOCF3)2(OTf)] (3) and [NH4]OTf. Compound 3, along with the ammonium salts [NMe4]OTf and [NMe4][Ti(eta5-C5Me5)(OTf)4] (5), was also obtained in the reaction of 1 with 8 equiv of methyl triflate in toluene at 100 °C. The trinuclear complex [Ti3(eta5-C5Me5)3(mu-N)(mu-NH)2(mu-O2SOCF3)(OTf)] (4), an intermediate in the formation of 3, was isolated in the treatment of 1 with 4 equiv of MeOTf, although compound 4 was prepared in better yield by treatment of 1 with Me3SiOTf (2 equiv). Addition of a large excess of MeOTf or HOTf reagents to solutions of 3 resulted in the clean formation of ammonium salts [NR4][Ti(eta5-C5Me5)(OTf)4] (R = Me (5), H (6)). Treatment of the tetranuclear nitrido complex [{Ti(eta5-C5Me5)}4(mu3-N)4] (2) with 1 equiv of ROTf in toluene afforded the precipitation of the ionic compounds [{Ti(eta5-C5Me5)}4(mu3-N)3(mu3-NR)][OTf] (R = H (8), Me (9)), while a large excess of HOTf led to the formation of [{Ti(eta5-C5Me5)}4(mu3-N)3(mu3-NH)][Ti(eta5-C5Me5)(OTf)4(NH3)] (10) by rupture of a fraction of tetranuclear molecules. Complex 2 reacted with 1 equiv of [M(eta5-C5H5)(CO)3H] (M = Mo, Cr) via hydrogenation of one nitrido ligand to give the molecular derivative [{Ti(eta5-C5Me5)}4(mu3-N)3(mu3-NH)] (11) and [{M(eta5-C5H5)(CO)3}2], while a second 1 equiv of [M(eta5-C5H5)(CO)3H] produced the ionic compounds....Ministerio de Ciencia, Innovación y Universidades de España, Ministerio de Educación y Ciencia de España, Universidad de Alcal
Reactivity with Electrophiles of Imido Groups Supported on Trinuclear Titanium Systems
Several trinuclear titanium complexes bearingamido mu-NHR, imido mu-NR, and nitrido mu(n)-N ligands have been prepared by reaction of [{Ti(eta(5)-C5Me5)(mu-NH)}(3)(mu(3)-N)] (1) with 1 equiv of electrophilic reagents ROTf (R = H, Me, SiMe3; OTf = OSO2CF3). Treatment of 1 with triflic acid or methyl triflate in toluene at room temperature affords the precipitation of compounds [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-NH)(2)(mu-NH2)(OTf)] (2) or [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-NH)(mu-NH2)(mu-NMe)(OTf)](3). Complexes 2 and 3 exhibit a fluxional behavior in solution consisting of proton exchange between mu-NH2 and mu-NH groups, assisted by the triflato ligand, as could be inferred from a dynamic NMR spectroscopy study. Monitoring by NMR spectroscopy the reaction course. of 1 with MeOTf allows the characterization of the methylamido intermediate [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-NH)(2)(mu-NHMe)(OTf)] (4), which readily rearranges to give 3 by a proton migration from the NHMe amido group to the NH imido ligands. The treatment of 1 with 1 equiv ofMe3SiOTf produces the stable ionic complex [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-NH)(2)(mu-NHSiMe3)][OTf] (5) with a disposition of the nitrogen ligands similar to that of 4. Complex 5 reacts with 1 equiv of [K{N(SiMe3)(2)}] at room temperature to give [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-N)(mu-NH)(mu-NHSiMe3)] (6), which at 85 degrees C rearranges to the trimethylsilylimido derivative [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-NH)(2)(mu-NHSiMe3)] (7). Treatment of 7 with [K{N(SiMe3)(2)}] affords the potassium derivative [K{(mu(3)-N)(mu(3)-NH)(mu(3)-NiSMe3)Ti-3(eta(C5Me5)-C-5)(3)(mu(3)-N)}] (8), which upon addition of 18-crown-6 leads to the ion pair [K(18-crown-6)] [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-NH)(mu-NHSiMe3)] (9). The X-ray crystal structures of2, 5, 6, and 8 have been determined.Ministerio de Ciencia e Innovación de España, Comunidad de Madrid, Universidad de Alcalá, Ministerio de Educación y Ciencia de Españ
Homo and Heteropolymetallic Group 4 Molecular Nitrides
Ministerio de Economía y Competitividad de España, Universidad de Alcal
Electrophilic attack on trinuclear titanium imido-nitrido systems
Alkylation of [{Ti(eta(5)-C5Me5)(mu-NH)}(3)(mu(3)-N)] with MeOTf occurs at the imido ligands to produce the methylamido derivative [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-NH)(2)(mu-NHMe)(OTf)] which readily rearranges to form the methylimido complex [Ti-3(eta(5)-C5Me5)(3)(mu(3)-N)(mu-NH)(mu-NH2)(mu-NMe)(OTf)].Ministerio de Educación y Ciencia de España, Comunidad de Madrid, Universidad de Alcal
Identificación de hojas de plantas usando Vectores de Fisher
En este trabajo se propone el uso de descriptores locales codificados con el método de Vectores de Fisher para resolver el problema de clasificación de hojas de plantas usando imágenes. Se demuestra que con este enfoque se obtienen resultados de estado del arte en conjuntos de datos públicos, sin la necesidad de recurrir a la creación de nuevos descriptores visuales específicos para el problema, ni la necesidad de realizar ningún preprocesamiento de las imágenes a analizar.Sociedad Argentina de Informática e Investigación Operativa (SADIO
Caracterización de mezclas de concreto utilizadas en Sistemas industrializados de construcción de Edificaciones
Mediante ensayos de laboratorio se llevó a cabo una caracterización físico - mecánica de los diferentes concretos que se utilizan en los sistemas industrializados de construcción de edificaciones, haciendo un análisis comparativo del comportamiento de este tipo de mezclas a diferentes edades (horas y días). Adicionalmente se contrastaron las principales propiedades mecánicas de estos concretos especiales con las del concreto convencional (bombeable) usado en la construcción de placas de sistemas tradicionales. Por otro lado se llevaron a cabo ensayos de calorimetría sobre los concretos usados en los sistemas industrializados con el fin de relacionar el diferencial máximo de temperatura (ETmax), tomado del perfil térmico, con la resistencia máxima esperada de la mezcla. Finalmente se desarrolló un prototipo para determinar el esfuerzo de adherencia entre el acero de refuerzo y el concreto con el fin de establecer la evolución de este esfuerzo en el tiempo
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