La pertinencia de la capacitación en el sector productivo. Análisis y resultados de la implementación del curso “Tecnología de los materiales Plásticos” (convenio UTN-FRAy la UOyEP)

El trabajo tiene por objeto describir la incumbencia de la vinculación entre la UTN-FRA y la UOyEP, en el marco de las relaciones entre universidad y empresa. Esta vinculación nació en el año 2002 y representa un ejemplo contundente sobre cómo desde los diferentes ámbitos –académicos, sindicales, industriales y empresariales– se pueden ejecutar políticas tendientes a la capacitación y a la especialización de los recursos necesarios para cumplimentar los requerimientos productivos de los distintos sectores. A estos fines, se hará un recorrido cronológico que dé cuenta de dichas relaciones, tomando como punto de referencia tanto a los indicadores internos como a los externos. En el primer caso se considerarán la cantidad de alumnos matriculados y egresados por año, desde el inicio de la institución. Los altibajos en la matrícula, las deserciones y los egresos servirán para interpretar las inflexiones del contexto en este ámbito. En el segundo caso se tomarán en consideración los siguientes factores: las fluctuaciones de la industria y las nuevas condiciones generadas por la crisis económica mundial del año 2008; las trabas a la capacitación de los obreros y por último, las políticas educativas que apuntan a fortalecer los vínculos generados por este tipo de instituciones

Delayed and time-variant patrolling strategies against attackers with local observation capabilities

Surveillance of graph-represented environments is an application of autonomous patrolling robots that received remarkable attention during the last years. In this problem setting, computing a patrolling strategy is a central task to guarantee an effective protection level. Literature provides a vast set of methods where the patrolling strategies explicitly consider the presence of a rational adversary and fully informed attacker, which is characterized by worst-case (for the patroller) observation capabilities. In this work, we consider an attacker that does not have any prior knowledge on the environment and the patrolling strategy. Instead, we assume that the attacker can only access local observations on the vertex potentially under attack. We study the definition of patrolling strategies under the assumption that the attacker, when planning an attack on a particular location, tries to forecast the arrivals of the patroller on that particular location. We model our patrolling strategies with Markov chains where we seek the generation of arrivals that are difficult to forecast. To this end we introduce time-variance in the transition matrix used to determine the patrollers movements on the graph-represented environment

Dilaton Quantum Cosmology with a Schrodinger-like equation

A quantum cosmological model with radiation and a dilaton scalar field is analysed. The Wheeler-deWitt equation in the mini-superspace induces a Schr\"odinger equation, which can be solved. An explicit wavepacket is constructed for a particular choice of the ordering factor. A consistent solution is possible only when the scalar field is a phantom field. Moreover, although the wavepacket is time dependent, a Bohmian analysis allows to extract a bouncing behaviour for the scale factor.Comment: 14 pages, 3 figures in eps format. Minors corrections, new figure

Perfect Fluid Quantum Anisotropic Universe: Merits and Challenges

The present paper deals with quantization of perfect fluid anisotropic cosmological models. Bianchi type V and IX models are discussed following Schutz's method of expressing fluid velocities in terms of six potentials. The wave functions are found for several examples of equations of state. In one case a complete wave packet could be formed analytically. The initial singularity of a zero proper volume can be avoided in this case, but it is plagued by the usual problem of non-unitarity of anisotropic quantum cosmological models. It is seen that a particular operator ordering alleviates this problem.Comment: 13 pages, 4 figures; Accepted for publication in Gen Relativ Gravi

Experimental observation of two-dimensional fluctuation magnetization in the vicinity of T_c for low values of the magnetic field in deoxygenated YBa_2Cu_3O_{7-x}

We measured isofield magnetization curves as a function of temperature in two single crystal of deoxygenated YBaCuO with T_c = 52 and 41.5 K. Isofield MvsT were obtained for fields running from 0.05 to 4 kOe. The reversible region of the magnetization curves was analyzed in terms of a scaling proposed by Prange, but searching for the best exponent $\upsilon$. The scaling analysis carried out for each data sample set with $\upsilon$=0.669, which corresponds to the 3D-xy exponent, did not produced a collapsing of curves when applied to MvsT curves data obtained for the lowest fields. The resulting analysis for the Y123 crystal with T_c = 41.5 K, shows that lower field curves collapse over the entire reversible region following the Prange's scaling with $\upsilon$=1, suggesting a two-dimensional behavior. It is shown that the same data obeying the Prange's scaling with $\upsilon$=1 for crystal with T_c = 41.5 K, as well low field data for crystal with $T_c$ = 52 K, obey the known two-dimensional scaling law obtained in the lowest-Landau-level approximation.Comment: 4 pages, 3 figure

Troubles with quantum anistropic cosmological models: Loss of unitarity

The anisotropic Bianchi I cosmological model coupled with perfect fluid is quantized in the minisuperspace. The perfect fluid is described by using the Schutz formalism which allows to attribute dynamical degrees of freedom to matter. A Schr\"odinger-type equation is obtained where the matter variables play the role of time. However, the signature of the kinetic term is hyperbolic. This Schr\"odinger-like equation is solved and a wave packet is constructed. The norm of the resulting wave function comes out to be time dependent, indicating the loss of unitarity in this model. The loss of unitarity is due to the fact that the effective Hamiltonian is hermitian but not self-adjoint. The expectation value and the bohmian trajectories are evaluated leading to different cosmological scenarios, what is a consequence of the absence of a unitary quantum structure. The consistency of this quantum model is discussed as well as the generality of the absence of unitarity in anisotropic quantum models.Comment: Latex file, 18 pages. To appear in General Relativity and Gravitatio

Nuevos Propósitos, Objetivos y Estrategias de la UTN frente al nuevo escenario mundial por la Pandemia

El desarrollo de este trabajo se enmarca en las actividades multidisciplinarias que la Universidad Tecnológica Nacional realiza sobre su accionar y proyección institucional como institución de Educación Superior Universitaria. Específicamente se describe, por un lado, las modificaciones organizacionales realizadas durante 2020, como proyección de las innovaciones permanentes que la UTN realiza; no obstante, se produjeron modificaciones al plan inicial como consecuencia de la pandemia por el COVID-19. Por el otro, se presentan parte de las investigaciones que se están llevando a cabo actualmente, en torno al análisis y planeamiento de un modelo de formación por competencias para la Reformulación del de la oferta académica en la UTN en avenencia con los lineamientos mundiales y todos los factores de cambios, sociales, tecnológicos, económicos y esencialmente humanos que necesariamente se deben proyectar, para la pertinencia de esta casa de estudios

Influência de aléias de leguminosas arbóreas na infestação de bicho-mineiro em cafeeiro.

O bicho-mineiro, Leucoptera coffeella (Guérin - Mèneville, 1842) (Lepidoptera: Lyonetiidae), é talvez a principal praga do cafeeiro (Coffea spp.) na atualidade, principalmente nas regiões de temperaturas mais elevadas e de maior déficit hídrico. Vários estudos indicam que a abundância e diversidade de insetos dentro de um campo podem estar intimamente relacionadas com a natureza da vegetação circundante. Considerando o exposto, foi objetivo deste trabalho observar o efeito de espécies de leguminosas arbóreas utilizadas como quebra-ventos (aléias) sobre os aspectos fitossanitários do cafeeiro. As leguminosas utilizadas foram: o Guandu (Cajanus cajan Millsp.), Bracatinga (Mimosa scabrella Benth.), Leucena (Leucaena leucocephala (Lam.) De Wit) e Acácia (Acacia mangium Willd.), plantadas perpendiculares ao sentido dos ventos predominantes. Os resultados parciais, obtidos em 2003, 2004, 2005 e 2006, mostram que a menor porcentagem de folhas com minas intactas foi observada nos cafeeiros sob Leucena e Guandu e também a menor porcentagem de minas predadas. Os cafeeiros sob Leucena e Guandu apresentaram nível de controle (NC) para o bicho-mineiro (30% de folhas minadas sem sinais de predação) no final de agosto enquanto que aqueles sob Acácia e Bracatinga foram semelhantes à testemunha e apresentaram NC bem mais cedo, no mês de junho

Assessment of soil physicochemical characteristics and As, Cu, Pb and Zn contamination in non-active mines at the Portuguese Sector of the

This study aimed to evaluate soil physicochemical characteristics (pH, electrical conductivity, organic matter, total N, and extractable P and K), and potentially toxic elements (As, Cu, Pb, and Zn), in non-active mines located in the Portuguese sector of the Iberian Pyrite Belt (IPB). A total of 70 sampling sites were surveyed at Aljustrel and Lousal, in areas already rehabilitated, and at São Domingos, where rehabilitation was only beginning. The soils at São Domingos were very heterogeneous, with extreme values for some properties (e.g., minimum soil pH 2.0 and maximum As concentration, 4382.8 mg kg1 dry weight basis (DW)). Aljustrel was the site that presented soils with a higher total As, Cu, Pb, and Zn concentration (median values: 441.5, 545.9, 1396.8, and 316.5 mg kg1 DW, respectively), above the soil quality guidelines values proposed by the Portuguese Environmental Agency (18, 230, 120, and 340 mg kg1 DW, respectively). A principal component analysis identified the most relevant soil properties to explain the data variance, which were the soil pH and Pb total concentration, followed by Cu and Zn total concentrations, allowing a separation of Aljustrel from the other mines. Pearson correlation coefficients revealed very strong associations between Pb and As, markedly found at higher concentrations in São Domingos, whereas Aljustrel had an elevated concentration of As and Pb, but also of Cu and Zn. It is evident the risk that persists in the Aljustrel mine area, which was not alleviated by the “dig, dump, and cover” techniques that were implemented to rehabilitate the area

Rendimento e perda de peso de bulbos de cebola cv. Texas Grano 502 PPR em diferentes espaçamentos de plantio.

Com o objetivo de avaliar o rendimento e as perdas de peso de bulbos de cebola armazenados em condições naturais, em diferentes espaçamentos de plantio, conduziu-se um experimento no período de abril a novembro de 1998 em Petrolina, PE. O delineamento experimental utilizado foi de blocos ao acoso no esquema fatorial 2x3, compreendendo dois espaçamentos entrelinhas (0, 10m e 0,15 m) e três espaçamentos entre plantas (0,10 m, 0,20 m e 0,30 m) e quatro repetições, sendo utilizada a cultivar Texas Grano 502 PRR. Foram avaliadas as produtividades comercial e não comercial, massa fresca e classificação de bulbos. As maiores produtividades comerciais de bulbos foram obtidas nos menores espaçaments entrelinhas e entre plantas. A massa fresca dos bulbos decresceu com o aumento nos espaçamentos entre plantas, enquanto que a perda de peso destes bulbos aumentou com o aumento nos espaçamentos entre plantas. As maiores percentagens de bulbos pequenos e médios foram registradas nos menores espaçamentos testados. Os espaçamentos de 0,15 m entrelinhas e 0,10 m entre plantas são os mais adequados para o cultivo da cultivar Texas Grano 502 PRR nas condições do Vale do São Francisco