141 research outputs found
Fuzzy Quasi-Metric Spaces: Bicompletion, Contractions on Product Spaces, and Applications to Access Predictions
Desde que L.A. Zadeh presentó la teoría de conjuntos difusos en 1965, esta se ha usado en una amplia serie de áreas de las matemáticas y se ha aplicado en una gran variedad de escenarios de la vida real. Estos escenarios cubren procesos complejos sin modelo matemático sencillo tales como dispositivos de control industrial, reconocimiento de patrones o sistemas que gestionen información imprecisa o altamente impredecible.
La topología difusa es un importante ejemplo de uso de la teoría de L.A. Zadeh. Durante años, los autores de este campo han buscado obtener la definición de un espacio métrico difuso para medir la distancia entre elementos según grados de proximidad.
El presente trabajo trata acerca de la bicompletación de espacios casi-métricos difusos en el sentido de Kramosil y Michalek. Sherwood probó que todo espacio métrico difuso admite completación que es única excepto por isometría basándose en propiedades de la métrica de Lévy. Probamos aquí que todo espacio casi-métrico difuso tiene bicompletación usando directamente el supremo de conjuntos en [0,1] y límites inferiores de secuencias en [0,1] en lugar de usar la métrica de Lévy.
Aprovechamos tanto la bicompletitud y bicompletación de espacios casi-métricos difusos como las propiedades de los espacios métricos difusos y difusos intuicionistas para presentar varias aplicaciones a problemas del campo de la informática.
Así estudiamos la existencia y unicidad de solución para las ecuaciones de recurrencia asociadas a ciertos algoritmos formados por dos procedimientos recursivos. Para analizar su complejidad aplicamos el principio de contracción de Banach tanto en un producto de casi-métricas no-Arquimedianas en el dominio de las palabras como en la casi-métrica producto de dos espacios de complejidad casi-métricos de Schellekens.
Estudiamos también una aplicación de espacios métricos difusos a sistemas de información basados en localidad de accesos.Castro Company, F. (2010). Fuzzy Quasi-Metric Spaces: Bicompletion, Contractions on Product Spaces, and Applications to Access Predictions [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8420Palanci
The bicompletion of fuzzy quasi-metric spaces
Extending the well-known result that every fuzzy metric space, in the sense of Kramosil and Michalek, has a completion which is unique up to isometry, we show that every KM-fuzzy quasi-metric space has a bicompletion which is unique up to isometry, and deduce that for each KM-fuzzy quasi-metric space, the completion of its induced fuzzy metric space coincides with the fuzzy metric space induced by its bicompletion. © 2010 Elsevier B.V.Supported by the Spanish Ministry of Science and Innovation, under Grant MTM2009-12872-C02-01.Castro Company, F.; Romaguera Bonilla, S.; Tirado Peláez, P. (2011). The bicompletion of fuzzy quasi-metric spaces. Fuzzy Sets and Systems. 166(1):56-64. https://doi.org/10.1016/j.fss.2010.12.004S5664166
On Yager and Hamacher t-Norms and Fuzzy Metric Spaces
Recently, Gregori et al. have discussed (Fuzzy Sets Syst 2011;161:2193 2205) the so-called strong fuzzy metrics when looking for a class of completable fuzzy metric spaces in the sense of George and Veeramani and state the question of finding a non-strong fuzzy metric space for a continuous t-norm different from the minimum. Later on, Gutíerrez-García and Romaguera solved this question (Fuzzy Sets Syst 2011;162:91 93) by means of two examples for the product and the Lukasiewicz
t-norm, respectively. In this direction, they posed to find further examples of nonstrong fuzzy metrics for continuous t-norms that are greater than the product but different from minimum. In this paper, we found an example of this kind. On the other hand, Tirado established (Fixed Point Theory 2012;13:273 283) a fixed-point theorem in fuzzy metric spaces, which was successfully used to prove the existence and uniqueness of solution for the recurrence equation associated with the probabilistic divide and conquer algorithms. Here, we generalize this result by using a class
of continuous t-norms known as ω-Yager t-norms.The second author acknowledges the support of the Ministry of Economy and Competitiveness of Spain under grant MTM2012-37894-C02-01 and the support of Universitat Politecnica de Valencia under grant PAID-06-12-SP20120471.Castro Company, F.; Tirado Peláez, P. (2014). On Yager and Hamacher t-Norms and Fuzzy Metric Spaces. International Journal of Intelligent Systems. 29:1173-1180. https://doi.org/10.1002/int.21688S1173118029Sherwood, H. (1966). On the completion of probabilistic metric spaces. Zeitschrift f�r Wahrscheinlichkeitstheorie und Verwandte Gebiete, 6(1), 62-64. doi:10.1007/bf00531809Gregori, V. (2002). On completion of fuzzy metric spaces. Fuzzy Sets and Systems, 130(3), 399-404. doi:10.1016/s0165-0114(02)00115-xGregori, V., Morillas, S., & Sapena, A. (2010). On a class of completable fuzzy metric spaces. Fuzzy Sets and Systems, 161(16), 2193-2205. doi:10.1016/j.fss.2010.03.013Gutiérrez García, J., & Romaguera, S. (2011). Examples of non-strong fuzzy metrics. Fuzzy Sets and Systems, 162(1), 91-93. doi:10.1016/j.fss.2010.09.017Yager, R. R. (1980). On a general class of fuzzy connectives. Fuzzy Sets and Systems, 4(3), 235-242. doi:10.1016/0165-0114(80)90013-5Castro-Company, F., & Tirado, P. (2012). Some classes of t-norms and fuzzy metric spaces. doi:10.1063/1.4756272George, A., & Veeramani, P. (1994). On some results in fuzzy metric spaces. Fuzzy Sets and Systems, 64(3), 395-399. doi:10.1016/0165-0114(94)90162-7Hadžić, O., & Pap, E. (2001). Fixed Point Theory in Probabilistic Metric Spaces. doi:10.1007/978-94-017-1560-7Klement, E. P., Mesiar, R., & Pap, E. (2000). Triangular Norms. Trends in Logic. doi:10.1007/978-94-015-9540-
Avance de la colección de Fernando Fernández de Velasco: del taller de Velázquez a Jacinto Meléndez
Recull de part dels estudis i comunicacions presentades al Congreso Internacional de Historia de la Pintura de Época Moderna. De Miguel Ángel a Goya, celebrat a Lleida (CIHPEM-Lleida 2013), del 18 al 20 de novembre de 2013.Esta selección de textos, a modo de pequeño corpus de soluciones y problemas de la historia de la pintura del período conocido como Edad Moderna, recoge parte de los estudios y comunicaciones presentados en el Congreso Internacional de Historia de la Pintura de Época Moderna. De Miguel Ángel a Goya celebrado en Lleida (CIHPEM-Lleida 2013), del 18 al 20 de noviembre de 2013. Dicho encuentro se inscribía dentro del ámbito de actuación científica del grupo de investigación ACEM para favorecer contactos, intercambios y sinergias entre algunos de los mejores especialistas, nacionales e internacionales, y paralelamente fijar lecturas o miradas con la pintura italiana, que sigue siendo, en toda Europa, el paradigma histórico del arte de la época moderna. En este sentido, podemos destacar, por ejemplo, las aportaciones de Gianluigi Colalucci, Carmen Garrido, Jaime García-Máiquez, Mauro Natale, Nicola Spinosa o Edoardo Villata
Study of Bacterial Community Composition and Correlation of Environmental Variables in Rambla Salada, a Hypersaline Environment in South-Eastern Spain
We studied the bacterial community in Rambla Salada in three different sampling
sites and in three different seasons and the effect of salinity, oxygen, and pH.
All sites samples had high diversity and richness (Rr > 30). The diversity indexes
and the analysis of dendrograms obtained by DGGE fingerprint after applying
Pearson’s and Dice’s coefficient showed a strong influence of sampling season. The
Pareto-Lorenz (PL) curves and Fo analysis indicated that the microbial communities
were balanced and despite the changing environmental conditions, they can preserve
their functionality. The main phyla detected by DGGE were Bacteroidetes (39.73%),
Proteobacteria (28.43%), Firmicutes (8.23%), and Cyanobacteria (5.14%). The majority
of the sequences corresponding to uncultured bacteria belonged to Bacteroidetes
phylum. Within Proteobacteria, the main genera detected were Halothiobacillus and
Roseovarius. The environmental factors which influenced the community in a higher
degree were the salinity and oxygen. The bacteria belonging to Bacteroidetes and
Proteobacteria were positively influenced by salinity. Nevertheless, bacteria related to Alpha- and Betaproteobacteria classes and phylum Firmicutes showed a positive
correlation with oxygen and pH but negative with salinity. The phylumCyanobacteria were
less influenced by the environmental variables. The bacterial community composition
of Rambla Salada was also studied by dilution-to-extinction technique. Using this
method, 354 microorganisms were isolated. The 16S sequences of 61 isolates
showed that the diversity was very different to those obtained by DGGE and with
those obtained previously by using classic culture techniques. The taxa identified by
dilution-to-extinction were Proteobacteria (81.92%), Firmicutes (11.30%), Actinobacteria
(4.52%), and Bacteroidetes (2.26%) phyla with Gammaproteobacteria as predominant
class (65.7%). The main genera were: Marinobacter (38.85%), Halomonas (20.2%),
and Bacillus (11.2%). Nine of the 61 identified bacteria showed less than 97%
sequence identity with validly described species and may well represent new taxa.
The number of bacteria in different samples, locations, and seasons were calculated
by CARD-FISH, ranging from 54.3 to 78.9% of the total prokaryotic population. Inconclusion, the dilution-to-extinction technique could be a complementary method to
classical culture based method, but neither gets to cultivate the major taxa detected by
DGGE. The bacterial community was influenced significantly by the physico-chemical
parameters (specially the salinity and oxygen), the location and the season of sampling.This research was supported by grants from the Dirección
General de Investigación Científica y Técnica (CGL2005-05947;
CGL2008-02399; CGL2011-25748), Ministerio de Economía y
Competitividad and from the Plan Andaluz de Invesigacion
(P07-CVI-03150; CVI06226), Spain
The deconstruction of the female character in Galdós: the case of Marianela and «La Peri»
El novelista canario Benito Pérez Galdós trazó en varias de sus obras un perfil canónico de la mujer española claramente diferenciado del atribuido, hasta el siglo XIX, por la tradición literaria en España. Esa construcción estética del personaje femenino implicó para el autor aportar la propuesta de un modelo literario y social nuevo, coincidente además con los postulados del republicanismo español de inicios del siglo XX, en el que militó. Para el escritor, la protagonista literaria debía trascender el papel convencional de esposa y madre hogareña hasta aportar estéticamente una proyección de futuro totalmente ajena al canon social vigente. Además, en toda su obra exploró y reinterpretó el papel de la mujer, tanto en la ficción narrativa y teatral como en el ensayo y el periodismo, hasta aportar modelos concretos como Marianela o «La Peri». En este trabajo se traza una lectura particular a partir de propuestas críticas contemporáneas, y se analiza la deconstrucción del personaje femenino galdosiano desde dos modelos singulares como las protagonistas de Marianela (1878) y Realidad (1889); asimismo se desarrolla un análisis de ambas obras a partir de las dimensiones física, psicológica y sociológica de sus protagonistas principales. La propuesta crítica de este trabajo se complementa con la contextualización del vínculo personal de Pérez Galdós con el transcurso político y social de su época, y con la relación del punto de vista aportado por el autor sobre la sociedad del momento como materia literaria y la pertenencia de la mujer a aquella.The Canarian novelist Benito Pérez Galdós depicted in several of his works a canonical profile of the Spanish woman unmistakably well differentiated from the one attributed, until the 19th century, by the literary tradition in Spain. This aesthetic construction of the female character implied for the author to contribute the proposal of a new literary and social model, also coinciding with the postulates of Spanish republicanism at the beginning of the 20th century, in which he militated. For the Canarian author, the female literary protagonist had to transcend the conventional role of the wife and homely mother to aesthetically provide a projection of the future totally alien to the current social canon. Furthermore, through all his literary work, he explored and reinterpreted the role of women both in narrative and theatrical fiction as well as in essays and journalism, to the point of providing specific models such as Marianela or «La Peri». In this work, the authors delineate a specific reading from contemporary critical proposals; as well as analyze the deconstruction of the Galdosian female character from two singular models such as the protagonists of Marianela (1878) and Realidad (1889); alongside the analysis of both works from the physical, psychological and sociological dimensions of their main protagonists. The critical proposal of this work is complemented by the contextualization of the personal bond of the writer of his studied works with the political and social course of his time, accompanied by the point of view provided by him on the society of the moment as a literary matter and the weight of women’s voice in it
The upper Valanginian of the Oliva section (Prebetic Zone, Valencia): facies analysis, biostratigraphy, C-isotope stratigraphy and organic geochemistry
The Upper Valanginian stratigraphic section of the sierra de la Oliva (Prebetic,
Valencia province) records a significant sedimentary episode which has
been named as ”Weissert Event”.This event is characterized by a positive excursion
in the δ13C profile, which have been considered to be linked to a
global perturbation in the carbon cycle, with environmental consequences
that have been the object of debate, especially the degree of oxygenation of
the sea bottom waters.We studied the sedimentary evolution during the late
Valanginian in a shallow platform setting, beginning with the drowning of
the early Valanginian carbonate platform, followed by a succession of shallowing-
upwards sequences, which define a general deepening-upward evolution.
The δ13C profile records a positive excursion during the late Valanginian,
and the biomarker study has revealed the episodic development of
anoxia, coeval to the deposition of organic rich facies, occurred during the
episode of maximum deepening of the platform.This study has demonstrated
that the “Weissert Event” has been recorded in the Prebetic platform, and
that the environmental perturbations gave place to the occasional development
of anoxia in a context of high organic productivityLa sección estratigráfica del Valanginiense superior de la sierra de la
Oliva (Prebético, provincia de Valencia) registra un interesante episodio sedimentario
que ha sido denominado “Evento Weissert”. Este evento está
caracterizado por una excursión positiva en los valores del δ13C, que se considera
ligada a una perturbación global en el ciclo del carbono, cuyas consecuencias
ambientales son objeto de discusión, especialmente las condiciones
de oxigenación en los fondos marinos. El estudio presentado aquí
muestra la evolución sedimentaria del Valanginiense superior en un ámbito
de plataforma somera, que comienza con el drowning de la plataforma carbonatada
del Valanginiense inferior, y continúa con una sucesión de secuencias
de somerización, que en conjunto definen una evolución general de
profundización. El perfil de δ13C registra una excursión positiva durante el
Valanginiense superior, y el estudio de los biomarcadores ha puesto de manifiesto
el desarrollo puntual de anoxia, simultáneo al depósito de facies
ricas en materia orgánica, ocurrido en el momento de mayor profundización
de la plataforma. Este estudio demuestra que el denominado “EventoWeissert”
quedó reflejado en la plataforma Prebética, y que las perturbaciones
ambientales locales dieron lugar al desarrollo puntual de anoxia en un contexto
de elevada productividad orgánic
A fixed point theorem for preordered complete fuzzy quasi-metric spaces and an application
We obtain a fixed point theorem for a type of generalized contractions on preordered complete fuzzy quasi-metric spaces which is applied to deduce, among other results, a procedure to show in a direct and easy fashion the existence of solution for the recurrence equations that are typically associated to Quicksort and Divide and Conquer algorithms, respectively.The second and third named authors thank the supports of the Universitat Politecnica de Valencia, grant PAID-06-12-SP20120471, and the Ministry of Economy and Competitiveness of Spain, grant MTM2012-37894-C02-01.Castro Company, F.; Romaguera Bonilla, S.; Tirado Peláez, P. (2014). A fixed point theorem for preordered complete fuzzy quasi-metric spaces and an application. Journal of Inequalities and Applications. 2014(122):1-11. doi:10.1186/1029-242X-2014-122S111201412
Stratigraphy and chemostratigraphy of the Valanginian (pro parte) from Loma Solana, Sierra de Quípar (External Subbetic, Cehegín, Murcia)
The stratigraphy, biostratigraphy and geochemistry (C stable isotopes
and RSTE trace elements) of a succession of Valanginian age outcropping in
Loma Solana (External Subbetic) is presented. The succession is composed of
two local sections, one cropping out to the west of Cehegín (Murcia) and another
in the Garranchal gorge, to the SSW of this locality. The lithology consists
of marl and marlstone rhythmically interbedded, which is typical of the
Carretero Fm of the Subbetic. The ammonite zones and subzones of the middle-
late early Valanginian and the complete late Valanginian, except for the
lattermost part, have been identified, without any evidence of stratigraphic
discontinuity between the two local sections. The δ13C curve show a similar
shape to those of the same age obtained in other basins and the positive excursion
of the δ13C characterizing the Weissert episode of environmental
change (EECWeissert) has been identified. The RSTE, redox sensitive trace elements,
analyzed do not show any particular increase as is typical of anoxic
events and consequently conclude that anoxia due not exist in this part of
the Subbetic basin during this EECSe presenta el estudio estratigráfico, bioestratigráfico y geoquímico de
una sucesión del Valanginiense que aflora en Loma Solana (Subbético Externo).
Se trata de una sección compuesta de dos secciones parciales, una
de ellas levantada al oeste de Cehegín (Murcia) y la otra en el barranco del
Garranchal, al SSO de dicha localidad. La litología,margas y margocalizas en
alternancia rítmica, es la típica de la Fm. Carretero, a la que corresponde. Se
identifican las zonas y subzonas de ammonites de la parte media-alta del Valanginiense
inferior y de todo el Valanginiense superior, excepto la parte más
terminal del mismo, sin que se haya denotado discontinuidad alguna entre
una sección y otra. La curva de valores de δ13C muestra una forma similar
a la obtenida en otras cuencas para la misma edad y en ella se puede identificar
la excursión positiva del δ13C que caracteriza el episodioWeissert de
cambio ambiental. Los elementos traza analizados, sensibles a cambios en
las condiciones redox del medio sedimentario (elementos RSTE), no indican
que hubiera condiciones anóxicas en el mismo durante este episodio de cambio
ambienta
Creel fishing and acoustic tracking trials in the No-Take zone off Palamós-Roses (Northwester Mediterranean Sea) at 350-420 m depth
Postprint (published version
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