La desregulación de las cooperativas eléctricas no concesionarias en chile: san pedro de atacama como paradigma de referencia

Este trabajo afrontará el contexto general del sistema eléctrico y su incidencia en casos excepcionales, particularmente con empresas no concesionaras de distribución, poniendo énfasis en un caso referencial de carácter rural, la Cooperativa Eléctrica de San Pedro de Atacama y su desenvolvimiento normativo y fáctico frente a la desregulaciónThis paper will address the general context of the electrical system and its impact in exceptional cases, particularly with non-concessional distribution companies, with an emphasis on a benchmark case of rural character, the Electric Cooperative of San Pedro de Atacama and its factual development policy and against deregulation

A pointwise tracking optimal control problem for the stationary Navier--Stokes equations

We study a pointwise tracking optimal control problem for the stationary Navier--Stokes equations; control constraints are also considered. The problem entails the minimization of a cost functional involving point evaluations of the state velocity field, thus leading to an adjoint problem with a linear combination of Dirac measures as a forcing term in the momentum equation, and whose solution has reduced regularity properties. We analyze the existence of optimal solutions and derive first and, necessary and sufficient, second order optimality conditions in the framework of regular solutions for the Navier--Stokes equations. We develop two discretization strategies: a semidiscrete strategy in which the control variable is not discretized, and a fully discrete scheme in which the control variable is discretized with piecewise constant functions. For each solution technique, we analyze convergence properties of discretizations and derive a priori error estimates

Fragility and vulnerability analysis of deteriorating ordinary bridges using simulated ground-motion sequences

Highway bridges are critical components of the lifeline transport infrastructure in urban areas. They are designed with the expectation of not sustaining significant structural/non-structural damage after major earthquake-induced ground shaking. However, in the current structural performance-based assessment practice, the effects of a pre-damaged state during ground-motion sequences are often neglected. Additionally, environmentally induced deterioration mechanisms (e.g., steel rebar corrosion) may exacerbate the consequences of such ground-motion sequences on the seismic structural performance during the bridge design lifetime; yet such effects are commonly overlooked. This study proposes a computational methodology to derive state-dependent fragility and vulnerability relationships (i.e., explicitly depending on the damage state achieved by the bridge structure during a first shock) for bridge structures subjected to chloride-induced corrosion deterioration and ground-motion sequences. The methodology is demonstrated for a case-study ordinary bridge structure (representing a typical bridge vulnerability class in southern California) under seismic sequences assembled from the CyberShake 15.12 (hybrid) simulated ground-motion database. In the proposed approach, parameterised (i.e., dependent on the corrosion deterioration level) vector-valued probabilistic seismic demand models are developed for the bridge components (i.e., columns and shear keys). These models, calibrated through sequential cloud-based nonlinear time-history analyses, relate the dissipated hysteretic energy in the ground-motion sequence to a deformation-based engineering demand parameter induced by the first shock and a ground-motion intensity measure of the second shock for a given corrosion deterioration level. Fragility relationships are first derived for a single ground motion at the component-level; state-dependent fragility relationships are then derived by considering the additional damage induced by a second ground motion within the simulated sequence (structure-specific damage states are considered). Furthermore, a component-based simulation approach accounting for the correlations across the components’ response is utilised to derive fragility relationships at the system level (i.e., for the bridge structure). Finally, appropriate damage-to-loss models for ordinary bridges are used to derive state-dependent vulnerability relationships. The results demonstrate the significant impact of earthquake-induced ground-motion sequences and environmentally-induced corrosion deterioration, emphasising the necessity of accounting for this multi-hazard threat in the structural performance-based assessment of bridges. Relative variations up to 120% can be found in the system-level state-dependent fragility median values comparing the results for the bridge in pristine and deteriorated conditions

Bryophyte and lichen biomass and nitrogen fixation in a high elevation cloud forest in Cerro de La Muerte, Costa Rica

Cloud forests have been found to lose more nitrogen in stream discharge than they gain from atmospheric deposition. They also support a large diversity and biomass of tree epiphytes, predominately composed of cryptogams. Since cryptogam epiphytes harbor nitrogen fixing cyanobacteria, they may help make up for the nitrogen loss from ecosystems. We assessed cryptogam biomass on the ground, boles and branches in Quercus costaricensis dominated stands near the tree line in the Cordillera de Talamanca, Costa Rica. Nitrogen fixation was assayed using 15N2 uptake. Total cryptogam biomass was 2 977 kg ha−1, with 67% being found on the lower branches. Bryophytes and chlorolichens made up 53% and 44%, respec- tively, of the biomass. Half of the bryophyte mass was composed of the liverwort Plagiochila heterophylla, and 66% of the chlorolichen of Lobariella pallida. There were no significant differences in nitrogen fixation rates between the cryptogam species, with a mean rate of 5.04 µg N g−1 day−1 during the predominantly wet condition in the forest. The overall nitrogen input from fixation was 6.1 kg N ha−1 year−1, of which 78% came from bryophytes, 18% from chlorolichens, and 4% from cyanolichens. Only 2.0% of the fixation occurred in cryptogams on the ground, whereas 67%, 24%, and 7% occurred on the lower branches, boles, and upper branches, respectively. These results show that tree epiphytes constitute a significant source of nitrogen for these forests, due to the trees’ large surface area, and can make up for the nitrogen lost from these ecosystemsUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologíaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Biodiversidad y Ecología Tropical (CIBET

A posteriori error estimation for a PDE-constrained optimization problem involving the generalized Oseen equations

We derive globally reliable a posteriori error estimators for a linear-quadratic optimal control problem involving the generalized Oseen equations as state equations; control constraints are also considered. The corresponding local error indicators are locally efficient. The assumptions under which we perform the analysis are such that they can be satisfied for a wide variety of stabilized finite element methods as well as for standard finite element methods. When stabilized methods are considered, no a priori relation between the stabilization terms for the state and adjoint equations is required. If a lower bound for the inf-sup constant is available, a posteriori error estimators that are fully computable and provide guaranteed upper bounds on the norm of the error can be obtained. We illustrate the theory with numerical examples

Fragility Analysis of Deteriorating Bridge Components Subjected to Simulated Ground-Motion Sequences

This study assesses the impact of corrosion deterioration on the seismic performance of bridge components during a sequence of ground motions. Specifically, a simplified methodology is proposed to derive state-dependent fragility relationships for bridge components (i.e., relationships that explicitly depend on the damage state achieved by the component during a first shock) subjected to chloride-induced corrosion deterioration and simulated ground-motion sequences. Specifically, vector-valued probabilistic seismic demand models are derived for various corrosion levels. Those models relate the dissipated hysteretic energy in the sequence to a deformation-based engineering demand parameter induced by the first shock and a ground-motion intensity measure of the second shock, calibrated via sequential cloud-based time-history analyses. For each corrosion level, fragility relationships are first derived for a single ground motion; state-dependent fragility relationships are then derived by considering the additional damage induced by a second ground motion within the simulated sequence (structure-specific damage states are considered). Finally, continuous functional models are developed from the analysis results to assemble fragility relationships at a given corrosion level. The results demonstrate the significant impact of environmental deterioration in seismic-prone regions, emphasising the necessity of accounting for deteriorating effects in current practice

Maximum–norm a posteriori error estimates for an optimal control problem

We analyze a reliable and efficient max-norm a posteriori error estimator for a control-constrained, linear–quadratic optimal control problem. The estimator yields optimal experimental rates of convergence within an adaptive loop. © 2019, Springer Science+Business Media, LLC, part of Springer Nature

La descripción del inmueble y la discordancia registral

The object of the article is to determine whether current legislative requirements prevent the existence of doubtful ownership rights due to imprecise or lacking identification of the property. In the event that they do not prevent it, we ask the following questions: Can the Real Estate Registrar register a title that has as its object a property whose area and/or boundaries differ from those defined in previous registrations of the property, or accede to a request for rectification of the same. Could the Registrar provide a solution to this situation through qualification of the registration? Does legitimization extend to the identification of the property? Faced with such questions, our working hypothesis is that the Real Estate Registrar can and should be the main architect of coordination between the physical reality and its representation, since title, registration and survey (if one exists) are the means by which the reality outside the register is represented. Whenever a registration is intended, the Registrar must assess the legality of the instrument through qualification of the registration, because in a constitutive registration system, such as exists in Chile, in every circumstance, even simple description of the property, the Registrar must verify that the legally established requirements are met, including the identification, location and delimitation of the propertyEl artículo ofrece un análisis para determinar si las exigencias legislativas vigentes evitan la existencia de derechos dudosos derivados de la falta o imprecisa identificación del inmueble. En el caso de que no lo impidan, se cuestiona sobre si ¿puede el Conservador de Bienes Raíces inscribir un título que tiene por objeto un bien raíz cuya superficie y/o deslindes difieren de aquellos que aparecían consignados en las inscripciones correlativas anteriores, o bien una solicitud de rectificación de estos? ¿Podría el Conservador dar solución a esta situación a través de la calificación registral? ¿Se extiende la legitimización a la identificación del inmueble? Frente a tales cuestionamientos, la hipótesis de trabajo es la siguiente: Conservador de Bienes Raíces puede y debe ser el principal artífice de la coordinación entre la realidad física y su representación, pues tanto el título, el Registro y el Catastro (si se llega a establecer uno) son los medios de representación de la realidad extrarregistral. Siempre que se pretenda una inscripción, el Conservador debe valorar la legalidad del instrumento a través de la calificación registral, pues en un sistema de inscripción constitutiva, como el nuestro, a cada circunstancia, aunque sea descriptiva del inmueble, el Conservador debe verificar que se reúnen los requisitos legalmente establecidos, entre otros, la identificación, ubicación y delimitación del inmuebleO artigo visa determinar se as exigências legislativas atuais impedem a existência de direitos duvidosos decorrentes da falta ou imprecisão da identificação do imóvel. Caso não impeçam isso, surge a questão se o Registro de Imóveis pode registrar um título cujo objeto é um imóvel cuja área de superfície e/ou limites diferem daqueles que apareceram nos registros correlatos anteriores, ou um pedido de retificação dos mesmos? O Registro pode resolver essa situação através da qualificação do registro? A legitimação se estende à identificação do imóvel? Diante destas questões, surge a hipótese de que o Registrador Imobiliário pode e deve ser o principal arquiteto da coordenação entre a realidade física e sua representação, já que o título, o Registro e o Cadastro (se for estabelecido) são os meios de representação da realidade extra-registral. Sempre que uma inscrição for solicitada, o Conservador deve avaliar a legalidade do instrumento através da qualificação do registro, pois em um sistema de inscrição constitutiva, como o nosso, o Conservador deve verificar se os requisitos legalmente estabelecidos são atendidos, entre outros, a identificação, localização e delimitação do imóvel, mesmo que seja descritivo do imóvel