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Conceptualización de los Conocimientos de un Experto en la Monitorización del Funcionamiento de una Línea de Producción de las Pulpas de Frutas
Lima,J.L.;
Información tecnológica , 2004, DOI: 10.4067/S0718-07642004000200019
Abstract: this work presents the conceptualization and formal presentation of knowledge that an expert technician uses in monitoring the functioning of a fruit pulp production line. using ideal, the knowledge-based systems development methodology, conceptual models of the knowledge that an expert uses, was obtained. the models were graphically documented and the knowledge map of the task that the expert performs was obtained. the formalization of the conceptual knowledge model was carried out by means of hybrid model of frames and production systems, aiming at the accomplishment of an object-oriented programming. in conclusion, the knowledge conceptualization achieved is quite complete and detailed and the formalization carried out was useful in the case analyzed
Alternative dark energy models: an overview
Lima, J. A. S.;
Brazilian Journal of Physics , 2004, DOI: 10.1590/S0103-97332004000200009
Abstract: a large number of recent observational data strongly suggest that we live in a flat, accelerating universe composed of ~ 1/3 of matter (baryonic + dark) and ~ 2/3 of an exotic component with large negative pressure, usually named dark energy or quintessence. the basic set of experiments includes: observations from sne ia, cmb anisotropies, large scale structure, x-ray data from galaxy clusters, age estimates of globular clusters and old high redshift galaxies (ohrg's). it is now widely believed that such results provide the remaining piece of information connecting the inflationary flatness prediction (wt = 1) with astronomical observations. from a theoretical viewpoint, they have also stimulated the current interest for more general models containing an extra component describing this unknown dark energy, and simultaneously accounting for the present accelerating stage of the universe. in this review we present a simplified picture of the main results and discuss briefly some difficulties underlying the emerging dark energy paradigm.
Larval development of Austinixa bragantina (Crustacea: Brachyura: Pinnotheridae) reared in the laboratory
Lima, J? de Farias;
Zoologia (Curitiba) , 2009, DOI: 10.1590/S1984-46702009000100020
Abstract: the zoeal and megalopal stages of austinixa bragantina coelho, 2005, a small pinnotherid crab found in association with ghost shrimps callichirus major (say, 1818) and lepidophthalmus siriboia felder & rodrigues, 1993 in the northeastern region of the state of pará, brazil, were reared in the laboratory from hatching to the megalopal stage. the duration of the larval period from hatching to megalopa was 28 days and the mean of duration for each larval stage was 6, 5, 5, 6, and 6 days, respectively. in the present study, the zoeal and megalopal stages are described and illustrated in detail.
Conceptualización de los Conocimientos de un Experto en la Monitorización del Funcionamiento de una Línea de Producción de las Pulpas de Frutas Conceptualization of an Expert’s Knowledge in Monitoring a Fruit Pulp Production Line Operation
J.L. Lima
Información Tecnológica , 2004,
Abstract: En este trabajo se presenta la conceptualización y la representación formal de los conocimientos que utiliza un técnico experto en la monitorización del funcionamiento de una línea de elaboración de pulpas de frutas. Utilizando IDEAL, metodología de desarrollo de Sistemas Basados en Conocimientos, se obtuvieron los modelos conceptuales de los conocimientos que emplea el experto. Los modelos se documentaron en forma gráfica y se obtuvo el Mapa de Conocimientos de la tarea que realiza el experto. La formalización del modelo conceptual de conocimientos se realizó mediante un modelo híbrido de marcos con sistemas de producción, apuntando a la realización de una programación orientada a objetos. En conclusión, la conceptualización de conocimientos lograda es bastante completa y profunda y la formalización realizada es adecuada al caso analizado This work presents the conceptualization and formal presentation of knowledge that an expert technician uses in monitoring the functioning of a fruit pulp production line. Using IDEAL, the knowledge-based systems development methodology, conceptual models of the knowledge that an expert uses, was obtained. The models were graphically documented and the Knowledge Map of the task that the expert performs was obtained. The formalization of the conceptual knowledge model was carried out by means of hybrid model of frames and production systems, aiming at the accomplishment of an object-oriented programming. In conclusion, the knowledge conceptualization achieved is quite complete and detailed and the formalization carried out was useful in the case analyzed
Alternative dark energy models: an overview
Lima J. A. S.
Brazilian Journal of Physics , 2004,
Abstract: A large number of recent observational data strongly suggest that we live in a flat, accelerating Universe composed of ~ 1/3 of matter (baryonic + dark) and ~ 2/3 of an exotic component with large negative pressure, usually named Dark Energy or Quintessence. The basic set of experiments includes: observations from SNe Ia, CMB anisotropies, large scale structure, X-ray data from galaxy clusters, age estimates of globular clusters and old high redshift galaxies (OHRG's). It is now widely believed that such results provide the remaining piece of information connecting the inflationary flatness prediction (W T = 1) with astronomical observations. From a theoretical viewpoint, they have also stimulated the current interest for more general models containing an extra component describing this unknown dark energy, and simultaneously accounting for the present accelerating stage of the Universe. In this review we present a simplified picture of the main results and discuss briefly some difficulties underlying the emerging dark energy paradigm.
Age of the Universe, Average Deceleration Parameter and Possible Implications for the End of Cosmology
J. A. S. Lima
Physics , 2007,
Abstract: A new expression to the total age of the Universe is derived in terms of the average deceleration parameter. This kinematic result holds regardless of the curvature of the universe as well as of the underlying gravity theory. It remains valid even in the context of brane-world motivated cosmologies. Since the present age parameter of the Universe is accurately adjusted to $H_0t_0 = 1$, it is shown that the time averaged value of the deceleration parameter is zero. This also means that the cosmic age today is exactly the one predicted by a relativistic flat cosmological model filled by K-matter, a fluid satisfying the equation of state $p = -{{1/3}}\rho$. By assuming the validity of this relation (in an average long time meaning), it is argued that the decelerating stages of the expansion must exactly be compensated by the accelerated phases, as if the observed Universe coasts forever. If this is true, the present accelerating stage must be followed by a subsequent decelerating phase as predicted by some recent scalar field and brane-world motivated cosmologies.
Thermodynamics of Decaying Vacuum Cosmologies
J. A. S. Lima
Physics , 1996, DOI: 10.1103/PhysRevD.54.2571
Abstract: The thermodynamic behavior of vacuum decaying cosmologies is investigated within a manifestly covariant formulation. Such a process corresponds to a continuous irreversible energy flow from the vacuum component to the created matter constituents. It is shown that if the specific entropy per particle remains constant during the process, the equilibrium relations are preserved. In particular, if the vacuum decays into photons, the energy density $\rho$ and average number density of photons $n$ scale with the temperature as $\rho \sim T^{4}$ and $n \sim T^{3}$. The temperature law is determined and a generalized Planckian type form of the spectrum, which is preserved in the course of the evolution, is also proposed. Some consequences of these results for decaying vacuum FRW type cosmologies as well as for models with ``adiabatic'' photon creation are discussed.
Cosmologies with Photon Creation and the 3K Relic Radiation Spectrum
J. A. S. Lima
Physics , 1996, DOI: 10.1023/A:1018850330860
Abstract: A new Planckian distribution for cosmologies with photon creation is derived using thermodynamics and semiclassical considerations. This spectrum is preserved during the evolution of the universe and compatible with the present spectral shape of the cosmic microwave background radiation(CMBR). Accordingly, the widely spread feeling that cosmologies with continuous photon creation are definitely ruled out by the COBE limits on deviation of the CMBR spectrum from blackbody shape should be reconsidered. It is argued that a crucial test for this kind of cosmologies is provided by measurements of the CMBR temperature at high redshifts. For a given redshift $z$ greater than zero, the temperature is smaller than the one predicted by the standard FRW model.
Alternative Dark Energy Models: An Overview
J. A. S. Lima
Physics , 2004, DOI: 10.1590/S0103-97332004000200009
Abstract: A large number of recent observational data strongly suggest that we live in a flat, accelerating Universe composed of $\sim$ 1/3 of matter (baryonic + dark) and $\sim$ 2/3 of an exotic component with large negative pressure, usually named {\bf Dark Energy} or {\bf Quintessence}. The basic set of experiments includes: observations from SNe Ia, CMB anisotropies, large scale structure, X-ray data from galaxy clusters, age estimates of globular clusters and old high redshift galaxies (OHRG's). Such results seem to provide the remaining piece of information connecting the inflationary flatness prediction ($\Omega_{\rm{T}} = 1$) with astronomical observations. Theoretically, they have also stimulated the current interest for more general models containing an extra component describing this unknown dark energy, and simultaneously accounting for the present accelerating stage of the Universe. An overlook in the literature shows that at least five dark energy candidates have been proposed in the context of general relativistic models. Since the cosmological constant and rolling scalar field models have already been extensively discussed, in this short review we focus our attention to the three remaining candidates, namely: a decaying vacuum energy density (or ${\bf \Lambda(t)}$ {\bf models}), the {\bf X-matter}, and the so-called {\bf Chaplygin-type gas}. A summary of their main results is given and some difficulties underlying the emerging dark energy paradigm are also briefly examined.
Note on Solving for the Dynamics of the Universe
J. A. S. Lima
Physics , 2001, DOI: 10.1119/1.1405506
Abstract: In a recent article, Faraoni proposed an alternative procedure to solve the Friedman-Lemaitre-Robertson-Walker (FLRW) cosmological equations. The basic result of that paper was obtained long ago through a different approach, which seems to be little known and deserves closer attention due to its pedagogical interest. The broad importance of this method is readily recognized by examining some additional cases not considered by Faraoni. Its instructive potential for introductory courses on cosmology has been positively verified by the author in many lectures during the last decade.
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