2,360 research outputs found
Overcoming the Westphalian Notion of Absolute Sovereignty : The Venezuelan Case with the Inter-American Convention of Human Rights
In 2012, Former Venezuelan President Hugo Chavez withdrew from the American Convention on Human Rights (ACHR or “the Convention”). He presented a letter issued by the Department of Foreign Affairs before the Secretary General of the Organization of American States (OAS). The denunciation became effective in 2013. Thereafter, no one could petition before the Inter-American Commission or the Inter-American Court (IACHR) to hold Venezuela accountable for human rights violations. Meanwhile, between 2014 and 2019, the government’s armed groups have killed more than 19,000 people
Monitoring of power system dynamics using a hybrid state estimator
Modern power systems are undergoing a transformation process where distributed energy re-sources together with complex load technologies are increasingly integrated. This, in addition to a sustained growth in electricity consumption and a lack of significant investment in trans-mission infrastructure, leads power systems to face with new stochastic operating behavior and dynamics and to operate under stressed conditions. Under such operating conditions, the occurrence of a potential disturbance may cause a partial or a total collapse. Therefore, in order to minimize the risk of collapses and their impact, new monitoring tools must be adopted, capable of providing the right conditions for dynamic wide-area monitoring.
The thesis presents a hybrid state estimator, that is a monitoring tool that combines fast synchronized phasor measurements with traditional measurements into a single scheme. It has the ability to estimate at high speed power system dynamics associated to slow and fast transient phenomena considering a reduced amount of phasor measurement units (PMUs). The developed scheme consists of two phases depending on the power system operating regime. In phase one the system is in stationary regime and bus voltages (magnitude and angle) together with related variables like power flows, current through lines, etc. are estimated by a static estimator at a low speed, which is determined by the supervisory control and data acquisition (SCADA) system. When a physical disturbance happens and the system is in transient regime phase two comes into operation. This time, two estimators work in sequence at high speed. First, a static state estimator is used to estimate bus voltages as soon as the synchronized phasor measurement set arrives. Then, a dynamic estimator is in charge of estimating dynamic states of all generators and motors in the system, even if the unit is not observed by a PMU. Full observability is re-stored through a novel data-mining based methodology, which defines, first, a PMU topology that allows monitoring the post-contingency bus voltage dynamics of the entire power system and, second, generates a number of bus voltage pseudo-measurements to extend the observability to the whole system
Sobre los aspectos biológicos de las respuestas pavlovianas dirigidas en el automoldeamiento
En el presente trabajo se aborda un problema importante que se le ha planteado a la Psicología del Aprendizaje Animal en las dos últimas décadas: la naturaleza de la respuesta automoldeada y su interpretación teórica. Desde la revisión, principalamente, de los trabajos efectuados con palomas, se determinan las características de dicha respuesta -tanto en sus aspectos condicionados como incondicionados- y se precisan los componentes que forman dichas cadenas conductuales, Finalmente, se sugieren para su interpretación teórica conceptos biológicos como el "desencadenamiento condicionado", los "sistemas de conducta" y la distinción estre "estímulos elicitantes y/o dirigentes"
Los reflejos condicionados según Howard Scott Liddell (1895-1962)
Si bien Howard Scott Liddell no forma parte de las figuras más importantes de la psicología estadounidense, realizó contribuciones significativas al estudio de los reflejos condicionados y las neurosis experimentales. Influido por el endocrinólogo escocés Sutherland Simpson, Liddell comenzó a estudiar el aprendizaje del laberinto en ovejas y cabras a las que se les había retirado quirúrgicamente la glándula tiroides. En estos experimentos, no se encontraron diferencias significativas en el aprendizaje del laberinto entre los animales tiroidectomizados y sus controles. Ello obligó a Liddell a buscar otros métodos y comenzó a utilizar la técnica de los refl ejos condicionados. En 1924, Liddell fundó y dirigió uno de los primeros laboratorios estadounidenses dedicado al estudio de este fenómeno en rumiantes. Nuestro trabajo, explorará los experimentos de Liddell que utilizaron esta técnica, así como sus ideas acerca de la naturaleza traumatizante de la misma. Finalizaremos mostrando que aunque Liddell utilizó el método de los reflejos condicionados nunca apoyó las propuestas fisiológicas realizadas por Pavlov. Muy al contrario, la base teórica de las ideas de Liddell estuvo en la teorías de W. B. Cannon.Although Howard Scott Liddell is not among the leading figures of American Psychology, his contributions to the study of conditioned reflex and experimental neurosis were significant. Under the influence of the Scottish endocrinologist Sutherland Simpson, Liddell started to study maze learning in sheep and goats without thyroids gland. These experiments did not find significant differences in learning between thyroidectomised and normal animals. Therefore, Liddell turned to the conditioned reflex method, and in 1924 he founded and directed one of the first American laboratories dedicated to the study of conditioned reflex in ruminants. In this paper, we will explore Liddell’s experiments and his ideas about the traumatizing nature of this technique. Finally, we will show that Liddell’s use of reflex conditioned method did not commit him to endorse Pavlov’s physiological ideas. On the contrary, Liddell’s ideas were based on the theory defended by W. B. Cannon.Ministerio de Educación y Ciencia SEJ2006-14090-C02-01/PSI
¿Existió un caso "Anna O." en la tradición pavloviana?
En 1929, Adolf Meyer invito a William Horsley Gantt a poner en marcha un laboratorio pavloviano en la Clínica Psiquiátrica Henry Phipps. En este laboratorio, Gantt inicio un programa de investigación acerca de los trastornos nerviosos en los perros que combinaba la metodología del reflejo condicional con la práctica de Meyer de preparar un ≪diagrama de la vida≫: observar y registrar todos los acontecimientos vitales importantes de un individuo. La influencia de Meyer en el estilo de investigación de Gantt no sólo es apreciable a nivel metodológico, el respeto del psiquiatra suizo hacia todas las posibilidades de interpretación también influyó en Gantt. El producto de todas estas influencias es palpable en su caso clínico más famoso, el caso Nick. En este trabajo, utilizamos materiales de archivo para explorar las experiencias de Gantt con Nick, su importancia para las propuestas de una psicopatología objetiva, y los esfuerzos creativos de un psicoanalista, Leon J. Saul, para interpretar la neurosis experimental de este animal.In 1929, Adolf Meyer invited William Horsley Gantt to establish a Pavlovian laboratory at the Henry Phipps Psychiatric Clinic. In this laboratory, Gantt launched a research program to investigate the nervous disturbances in dogs. This program combined the Pavlovian methodology of conditional reflex with Adolf Meyer’s practice of composing a ≪life chart≫ –of observing and recording every event in the life of an individual. Meyer´s influence on Gantt’s style of research is not only discernible on a methodological level: his precept of respect toward the different possibilities of interpretation also influenced his theoretical approach. The product of these converging influences is fully evident in Gantt’s most famous clinical case –that of Nick. In this paper, we use archival materials to explore Gantt’s experiences with Nick, their significance for Gantt’s proposal of an objective psychopathology, and the creative efforts of a psychoanalyst, Leon J. Saul, to interpret Nick’s experimental neurosis
Spatial spillovers in public expenditure on a municipal level in Spain
A key function of local governments is to provide a wide array of public services. The supply of these services has been found to create spatial spillovers among neighbouring municipalities. Although it is generally agreed that spillovers are present in models that explain government expenditures, their type—whether endogenous, exogenous or residual—and sign—whether positive or negative—remain ambiguous. In most cases, a subjective process is used to select the type of spatial regression model used in analysis, with mixed results. Per capita expenditures of ten subprogrammes (Security, Housing, Welfare, Environment, Social services, Employment promotion, Health, Education, Culture and Sport) are analysed for all Spanish municipalities with more than 5000 inhabitants in the 2010–2012 period. A Spatial Seemingly Unrelated Regression methodology in a panel framework is used to incorporate correlation between different subprogrammes and spatial dependence. Our results show that the three types of spatial effects are present. Furthermore, substantive dependence is positive in most cases, while negative residual dependence is observed in some.We gratefully acknowledge the contribution of three anonymous reviewers in helping us improve the quality of this paper. Prof. Fernando A. López , grateful for the financial support offered by the projects from Programa de Ayudas a Grupos de Excelencia de la Región de Murcia, Fundación Seneca (#19884-GERM-15) and Ministry of Economy and Competiveness (ECO2015-651758)
Global existence and exponential decay for hyperbolic dissipative relativistic fluid theories
We consider dissipative relativistic fluid theories on a fixed flat, compact,
globally hyperbolic, Lorentzian manifold. We prove that for all initial data in
a small enough neighborhood of the equilibrium states (in an appropriate
Sobolev norm), the solutions evolve smoothly in time forever and decay
exponentially to some, in general undetermined, equilibrium state. To prove
this, three conditions are imposed on these theories. The first condition
requires the system of equations to be symmetric hyperbolic, a fundamental
requisite to have a well posed and physically consistent initial value
formulation. The second condition is a generic consequence of the entropy law,
and is imposed on the non principal part of the equations. The third condition
is imposed on the principal part of the equations and it implies that the
dissipation affects all the fields of the theory. With these requirements we
prove that all the eigenvalues of the symbol associated to the system of
equations of the fluid theory have strictly negative real parts, which in fact,
is an alternative characterization for the theory to be totally dissipative.
Once this result has been obtained, a straight forward application of a general
stability theorem due to Kreiss, Ortiz, and Reula, implies the results above
mentioned.Comment: 10 pages, Late
- …