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Search Results: 1 - 10 of 3014 matches for " Amilvia Acosta "
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Densidad poblacional y estructura de grupo de Ateles hybridus brunneus (Primates: atelidae) en un fragmento de bosque aislado en el suroriente de antioquia, Colombia
Roncancio,Néstor J; García,Lina M; Acosta,Amilvia;
Mastozoolog?-a neotropical , 2010,
Abstract: there was a group of a. h. brunneus in an isolated forest fragment of 21 ha, with a density of 39 individuals/ km2 (95% ci = 21.3-72.9). this is the smallest area where high density is estimated to ateles. the group of a. h. brunneus was composed of nine individuals, being smaller than that recorded in other investigations. ateles has a fission-fusion social system, where groups are divided into subgroups. the average size group of four individuals per subgroup was not different from that reported in other investigations. the ratios male-female and female-immature were 1:0.67 and 1:2 respectively.
Néstor J. Roncancio,Lina M. García,Amilvia Acosta
Mastozoolog?-a neotropical , 2010,
Abstract: Se encontró un grupo de Ateles hybridus brunneus en un fragmento de bosque aislado de 21 ha, con una densidad de 39 individuos/km2 (IC95% = 21.3-72.9). Esta área es la más peque a donde se ha estimado alta densidad para Ateles. El grupo de A. h. brunneus estuvo compuesto por nueve individuos, grupo más peque o que el registrado en otras investigaciones. Ateles tiene un sistema social fisión-fusión, donde los grupos se dividen en subgrupos. El tama o promedio de subgrupo fue de cuatro individuos y no difiere del registrado en otras investigaciones. Las proporciones machos-hembras y hembras- inmaduros fueron 1:0.67 y 1:2 respectivamente.
Effects of Solar UV Radiation on Materials Used in Agricultural Industry in Salta, Argentina: Study and Characterization  [PDF]
Carlos Cadena, Delicia Acosta
Journal of Materials Science and Chemical Engineering (MSCE) , 2014, DOI: 10.4236/msce.2014.24001
Abstract: The current study presents the characterization of three types of materials after exposure to solar UV radiation. The selection of the materials is related to socio-economic aspects and rural activities in the northwest of Argentina (a.k.a. NOA). The objective was to establish a time parameter that allows estimating the durability of the materials according to their use. One of the materials is used as a protective cover (polyethylene film) of greenhouses, which are used for crop cultivation in the area. Another material is used in photovoltaic modules (PVMs), which are used to supply energy in isolated areas and the third material is sunscreen used by people that are exposed to UV radiation during rural activities. Degradation or deterioration of the materials was monitored using different spectroscopic assays: infrared was used to detect any structural changes in the material, X-rays were used for possible changes in the crystalline structure of the material, and spectral transmittance as this property is likely to be affected by changes in the structure of the material. The results showed that degradation of polyethylene seems to be related to the diminution in transparency and the loss of mechanical resistance with increasing exposure time. The decrease in transparency of one of the layers of a PVM caused a considerable decrease in the energy generated, whereas the sunscreens with a low sun protection factor (SPF) rapidly lost their protective properties and changed their photostability properties. Our results revealed a relationship between relative transmittance loss and exposure timse, which allows estimating the stability of different materials.
Furuta's Pendulum: A Conservative Nonlinear Model for Theory and Practise
J. á. Acosta
Mathematical Problems in Engineering , 2010, DOI: 10.1155/2010/742894
Abstract: Furuta's pendulum has been an excellent benchmark for the automatic control community in the last years, providing, among others, a better understanding of model-based Nonlinear Control Techniques. Since most of these techniques are based on invariants and/or integrals of motion then, the dynamic model plays an important role. This paper describes, in detail, the successful dynamical model developed for the available laboratory pendulum. The success relies on a basic dynamical model derived from Classical Mechanics which has been augmented to compensate the non-conservative torques. Thus, the quasi-conservative “practical” model developed allows to design all the controllers as if the system was strictly conservative. A survey of all the nonlinear controllers designed and experimentally tested on the available laboratory pendulum is also reported.
Vigencia de la filosofía de Kant en dos expresiones actuales de la inteligencia filosófica en América Latina: Arturo Andrés Roig y Franz J. Hinkelammert
Estudios de filosof?-a pr??ctica e historia de las ideas , 2006,
Abstract: currency of kant's philosophy in two recent expressions of the philosophical intelligence in latin america: arturo andrés roig and franz j. hinkelammert. when it is twohundred years of immanuel kant′s death (2004), to consider the currency of his philosophical thought means a categorial must, for those who are involved in the tradition of occidental philosophy. taking this into account, the next introduced is based on the currency of the philosopher of k?nigsberg from the consideration of two expressions of the philosophical intelligence in latin america: arturo andrés roig (mendoza, argentina,1922) y franz j.hinkelammert (emsdetten, germany,1931). the curriculums of investigation of the chosen authors in the search and developement of different topics, come, from the point of view of arguments, from, against and beyond kant, showing a particular currency of his philosophy within them. in arturo andrés roig′s thought, the topics of reference considered are: normativity of philosophical thought, philosophy of history, the explanation of an emergent morality and of a motivational aesthetics. from the theoretical production of franz j. hinkkelammert, we introduce: the criticism to utopical reason and the political realism, the outstanding criticism of the categorical frames of social thoughts, the trascendentality of the subject and the question of ethical universalism in the tension between ethics of responsability and the ethics of principles. it comes out from the previous topics that, in relation to kant′s abstrac universalism, these two samples of philosophical intelligence in latin america, are gathered in the foundation of a concrete universalism.
Historia de las ideas e identidad
Estudios de filosof?-a pr??ctica e historia de las ideas , 2009,
Abstract: we focus on the history of ideas in america as a discipline and on its contributions to the elucidation of the question of identity of our america. in order to meet this fundamental objective, we use the periodization proposed by horacio cerutti guldberg from which the lines of reflection of the article are moving. we assume in its heuristic potential the tension and alternation between identity and modernization on which eduardo devés valdés builds his history of latin american thought of the twentieth century, discussing, from this interpretative framework, the history of ideas as an emergency of identity among modernist hegemonies, as well as its possible role between the critical theory and the single thought, especially when considering it -with arturo andrés roig- as the other side of the latin american philosophy. we characterize the consolidation and foundation stages paying special attention to the development of the question of identity, and dealing afterwards with the methodological renovation, understood as a deep epistemological conversion. we then consider the analytical deconstruction raised by javier sasso and the postmodern critic developed by santiago castro gómez, as well as the answers to both posed by arturo andrés roig. finally, we outline some contributions from the history of ideas to the question of the latin american identity in the present globalization context.
El cultivo del maíz, SU origen y clasificación. EL MAIZ en Cuba
Cultivos Tropicales , 2009,
Abstract: knowing about maize origin and classification as well as of the theories protecting crop evolutionary processes are subjects of great interest nowadays. this review presents an outlook of the most controversial theories in this regard and a debate on maize race classification in cuba, as well as the role of landraces related to in situ diversity preservation and generation
Finanzas y moneda internacionales al servicio del ser humano: Una propuesta desde la utopía
Polis (Santiago) , 2009, DOI: 10.4067/S0718-65682009000100011
Abstract: the article provides an interpretation of the current financial crisis as part of an economic crisis that has a series of synchronized facets, -apart from the financial, in environmental, energy, food, eventual- preludes of a deep one and prolonged civilizatory crisis. arguments the necessity not to reduce attention only to the current themes and to design a strategy that will permit to establish the structural bases for change, taking advantage of the current difficulties and the relative weaknesses of the world centers of power. it presents three proposals that aim toward the construction of a new and better international economic system, pillars on which a new world monetary and financial system can start its design: an international financial code; a world central bank, and an international court of arbitration of sovereign debt. it also proposses the need to rethink integrally the world organization of commerce (omc), as well as the creation of a world organization for environment and climatic change and to move ahead towards a universal statement of the rights of nature, just as ecuador's constituent assembly did. the object of this strategy that is barely outlined, is the good life of the people.
Los organizadores previos: Una estrategia de ense?anza para el logro de un aprendizaje significativo
Revista de la Facultad de Ingeniería Universidad Central de Venezuela , 2010,
Abstract: in the course general chemistry ii, faculty of engineering, university of carabobo, a traditional teaching methodology is used, which consists essentially of a repetition of concepts, definitions and theories. the main problem with this type of instruction is that students do not learn effectively, because when they are repeated only for knowledge of the evaluation processes, the result is low academic performance. in contrast to this situation we present as an alternative in the constructivist approach a student active in the educational process, which imposes a significant learning that enables the student to be linked to their environment. the objective of this study is to determine the effect of the use of advance organizers as a methodological strategy of education for achieving significant learning in the performance of students in general chemistry ii, faculty of engineering university of carabobo. the study is a quasi-experimental, and was developed by two groups, one experimental and one control, with pre-test and post-test. once the sample is selected, the advance organizers were applied to the experimental group to examine the effect of the treatment. then the respective results were compared using student ?t? test. the hypothesis test accepted the alternative hypothesis of the study, concluding that the implementation of advance organizers as a teaching strategy for achieving significant learning positively influenced the performance of students in general chemistry ii.
El sistema internacional del siglo XXI: Entre el terrorismo de Estado y la Democracia*
Utopìa y Praxis Latinoamericana , 2007,
Abstract: some reflections on the current meanings of ?the international?, prelude the approach of the international system in the xxi century as a matter. it is summarizely considered the interestate system and the one of the united nations, to focus the crisis of the latest in the current context. pointing at the state terrorism of the world dictatorship of national security, the option for the crisis of the international system seems to be placed in a state of democratic right, built in reference to the cosmopolitan substantive democracy as its main idea and in reference to the substantive human rights of allthe people and communities as its criteria.
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