Matemática

La Ingeniería Industrial juega actualmente un rol esencial en el monitoreo de procesos que siguen la metodología Six Sigma. Las Cartas de Control Estadístico permiten monitorearlos periódicamente. La velocidad de su respuesta es evaluada mediante la Longitud de Corrida y merece atención especial, juega un papel determinante en la búsqueda de una carta que se ajuste a las características de producción. La elevada dispersión y marcada asimetría de la Longitud de Corrida hacen que la Variabilidad Total (Coeiciente de Variación) no describa adecuadamente la dispersión de aquella longitud. En publicaciones anteriores, los autores propusieron variabilidades laterales acordes a cada estado del proceso. El objetivo del trabajo es evaluar cuantitativamente las ventajas de su uso. El método empleado fue el análisis de la razón variabilidad lateral/variabilidad total en cartas seleccionadas. Los resultados alcanzados evidencian tales ventajas, se hacen más notorias en el uso de muestras y en el interés por los corrimientos grandes en la media del proceso. Se ilustran dos casos donde se destacan las diferencias entre los criterios convencional y no convencional para evaluar la velocidad de respuesta de una carta.

La Ingeniería Industrial juega actualmente un rol esencial en el monitoreo de procesos que siguen la metodología Six Sigma. Las Cartas de Control Estadístico permiten monitorearlos periódicamente. La velocidad de su respuesta es evaluada mediante la Longitud de Corrida y merece atención especial, juega un papel determinante en la búsqueda de una carta que se ajuste a las características de producción. La elevada dispersión y marcada asimetría de la Longitud de Corrida hacen que la Variabilidad Total (Coeiciente de Variación) no describa adecuadamente la dispersión de aquella longitud. En publicaciones anteriores, los autores propusieron variabilidades laterales acordes a cada estado del proceso. El objetivo del trabajo es evaluar cuantitativamente las ventajas de su uso. El método empleado fue el análisis de la razón variabilidad lateral/variabilidad total en cartas seleccionadas. Los resultados alcanzados evidencian tales ventajas, se hacen más notorias en el uso de muestras y en el interés por los corrimientos grandes en la media del proceso. Se ilustran dos casos donde se destacan las diferencias entre los criterios convencional y no convencional para evaluar la velocidad de respuesta de una carta.

Aim: This study was carried out to investigate the antioxidant and antimicrobial activities of essential oil from the aerial part of Caralluma europaea and to evaluate the synergistic potential between essential oil and antibiotics. Methodology: The chemical composition, antioxidant, antimicrobial activities and synergetic interaction between antimicrobial agents and essential oil isolated by hydrodistillation from the aerial part of C. europaea were evaluated. The chemical composition was analyzed by a Gas Original Research Article

Hairy vetch (Vicia villosa ssp. villosa Roth) is native of Europe and Western Asia and it is the second most cultivated vetch worldwide. Hairy vetch is used as forage species in semiarid environments and as a legume cover crop in sub-humid and humid regions. Being an incompletely domesticated species, hairy vetch can form spontaneous populations in a new environment. These populations might contain novel and adaptive traits valuable for breeding. Niche occupancy based on geographic occurrence and environmental data of naturalized populations in central Argentina showed that these populations were distributed mainly on disturbed areas with coarse soil texture and alkaline-type soils. Low rainfall and warm temperatures during pre-and post-seed dispersal explained the potential distribution under sub-humid and semiarid conditions from Pampa and Espinal ecoregions. Conversely, local adaptation along environmental gradients did not drive the divergence among recently established Argentinian (AR) populations. The highest genetic diversity revealed by microsatellite analysis was observed within accessions (72%) while no clear separation was detected between AR and European (EU) genotypes, although naturalized AR populations showed strong differentiation with the wild EU accessions. Common garden experiments were conducted in 2014-16 in order to evaluate populations' germination, flowering, and biomass traits. European cultivars were characterized by low physical seed dormancy (PY), while naturalized AR accessions showed higher winter biomass production. Detected variation in the quantitative assessment of populations could be useful for selection in breeding for traits that convey favorable functions within specific contexts.

Aim: This study was carried out to investigate the antioxidant and antimicrobial activities of essential oil from the aerial part of Caralluma europaea and to evaluate the synergistic potential between essential oil and antibiotics. Methodology: The chemical composition, antioxidant, antimicrobial activities and synergetic interaction between antimicrobial agents and essential oil isolated by hydrodistillation from the aerial part of C. europaea were evaluated. The chemical composition was analyzed by a Gas Original Research Article

Given an endofunctor T in a category C, a coalgebra is a pair (X, c) consisting of an object X and a morphism c : X → T (X). X is called the carrier and the morphism c is called the structure map of the T -coalgebra. The theory of coalgebras has been found to abstract common features of different areas like computer program semantics, modal logic, automata, non-wellfounded sets, etc. Most of the work on concrete examples, however, has been limited to the category Set. The work developed in this dissertation is concerned with the category Meas of measurable spaces and measurable functions. Coalgebras of measurable spaces are of interest as a formalization of Markov Chains and can also be used to model probabilistic reasoning. We discuss some general facts related to the most interesting functor in Meas,∆, that assigns to each measurable space, the space of all probability measures on it. We show that this functor does not preserve weak pullbacks or ω-limits, conditions assumed in man...

Nelson algebras are defined in [BM67] in terms of the language 〈∧,∨,→,∼, 1〉. In 1962, Diana Brignole [Bri65], solved the problem proposed by Antonio Monteiro, of giving an axiomatization of Nelson algebras in terms of the connectives ֌, ∧ and the constant 0 =∼ 1. In this work we present for the first time a complete proof of this fact, and also show the dependence and independence of some of the axioms proposed by Brignole.

Let $P(n)$ be the set of all posets with $n$ elements and $NIP(n)$ the set of non-isomorphic posets with $n$ elements. Let $P^{(j)}(n)$, $1\leq j\leq 2^n,$ be the number of all posets with $n$ elements possessing exactly $j$ antichains. We have determined the numbers $P^{(j)}(7),$ $1\leq j\leq 128$, and using a result of M. Ern\'e \cite{EM4}, we compute $|P(10)|$ without the aid of any computer program. We include the Hasse diagrams of all the non-isomorphic posets of $P(7)$.

Let $P(n)$ be the set of all posets with $n$ elements. Let $P^{(j)}(n)$, $1\leq j\leq 2^n,$ be the number of all posets with $n$ elements possessing exactly $j$ antichains. We have determined the numbers $P^{(j)}(7),$ $1\leq j\leq 128$, and using a result of M.~Ern\'e [Ern\'e, M., On the cardinalities of finite topologies and the number of antichains in partially ordered sets, Discrete Mathematics 35 (1981), 119-133.], we compute $|P(10)|$ without the aid of any computer program. We include the Hasse diagrams of all the non-isomorphic posets of $P(7)$. We also present formulas for the number of connected posets of certain forms, and use them to compute $|P(n)|$ with $1\le n\le 8$ by a different method.

Defeasible Logic Programming (DELP) is a formalism that extends declarative programming to capture defeasible reasoning. Its inference mechanism, upon a query on a literal in a program, answers by indicating whether or not it is warranted in an argumentation process. While the properties of DELP are well known, some of its basic elements can be redefined in order to shed light on some of the subtleties of the warrant process. We will discuss these alternative definitions and the cases in which they provide a better performance.

We provide a recursive construction of all the semi-Heyting algebras that can be defined on a chain with n elements. This construction allows us to count them easily. We also compare the formula for the number of semi-Heyting chains thus obtained to the one previously known.

The notions of symmetry and anonymity in strategic games have been formalized in different ways in the literature. We propose a combinatorial framework in which those notions are systematized, using group actions. The same framework is used to define partial symmetries in games. With this purpose, we introduce the notion of the role a player plays with respect to another one, and combinatorial relations between roles are studied. Building on them, we define relations directly between players, which provide yet another characterization of symmetry in games.

The Vakarelov construction of Nelson algebras up from Heyting ones is generalized to obtain De Morgan algebras from distributive lattices. Necessary and sufficient conditions for these De Morgan algebras to be Nelson algebras are shown, and a characterization of the join-irreducible elements in the finite case is given.Fil: Monteiro, Luiz F.. Universidad Nacional del Sur; ArgentinaFil: Viglizzo, Ignacio Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Matemática Bahía Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática Bahía Blanca; ArgentinaXIV Congreso Dr. Antonio A. R. MonteiroBahía BlancaArgentinaUniversidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática de Bahía Blanc

We present a category equivalent to that of semi-Nelson algebras. The objects in this category are pairs consisting of a semi-Heyting algebra and one of its filters. The filters must contain all the dense elements of the semi-Heyting algebra and satisfy an additional technical condition. We also show that in the case of dually hemimorphic semi-Nelson algebras, the filters are not necessary and the category is equivalent to that of dually hemimorphic semi-Heyting algebras.