43 research outputs found

    Valorización económica de áreas verdes en la ciudad de La Paz, Bolivia

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    Universidad Nacional Agraria La Molina. Escuela de Posgrado. Doctorado en Economía de los Recursos Naturales y el Desarrollo SustentableEl objetivo del presente trabajo es determinar el valor económico de las áreas verdes en la ciudad de La Paz, Bolivia para realizar análisis de política pública, a partir de la estimación de la demanda implícita por áreas verdes como atributos de entorno de las viviendas, expresada en una medida monetaria, para el año 2015. Se evalúa en términos económicos y monetarios los beneficios ambientales de las áreas verdes, sus implicaciones de política pública y sus efectos en el precio de las viviendas en la ciudad de La Paz. A partir de la identificación de unidades de vegetación por superficie de área verde de los diferentes parques públicos de la ciudad, se aplica el “método de precios hedónicos”, una metodología de valoración de bienes no mercadeables indirecta, destinada a vincular los precios de una vivienda en función de sus características y de los atributos ambientales de su entorno. Este método infiere valores ambientales del bien a través del precio de inmuebles diferentes bajo condiciones estructurales de la vivienda similares. Se encontró que un incremento del 100% en la característica unidades de vegetación por metro cuadrado de área verde, eleva el precio por metro cuadrado de la vivienda, en 7,04%. El precio promedio implícito de una unidad de vegetación por metro cuadrado de área verde es de US.21.05;valornoconstante,dadoqueelpreciodependedelniveldelacaracterıˊstica.Unincrementodel100. 21.05; valor no constante, dado que el precio depende del nivel de la característica. Un incremento del 100 % en la característica distancia al área verde más cercana a la vivienda, disminuye el precio de equilibrio por metro cuadrado construido de la vivienda en 6.80 %. No se encontraron trabajos similares que permitan realizar efectos de comparación tanto en el contexto latinoamericano como mundial por las características de las variables del estudio en cuestión.The objective of this paper is to determine the economic value of green areas in the city of La Paz, Bolivia to carry out public policy analysis, based on the estimation of the implicit demand for green areas as attributes of the housing environment, expressed in a monetary measure, for the year 2015. The environmental benefits of the green areas, their implications of public policy and their effects on the price of housing in the city of La Paz are evaluated in economic and monetary terms. From the identification of units of vegetation by area of green area of the different public parks of the city, the "hedonic price method" is applied, a methodology of valuation of indirect non-merchantable goods, destined to link the prices of a housing according to their characteristics and the environmental attributes of their environment. This method infers environmental values of the property through the price of different properties under similar structural housing conditions. It was found that a 100% increase in the characteristic units of vegetation per square meter of green area, increases the price per square meter of the house, by 7.04%. The implicit average price of one unit of vegetation per square meter of green area is US . 21.05; non-constant value, since the price depends on the level of the characteristic. An increase of 100% in the characteristic distance to the green area closest to the house, decreases the equilibrium price per built square meter of the house by 6.80%. We did not find similar works that allow comparison effects in the Latin American and global context due to the characteristics of the variables of the study in question.Tesi

    Optimization of existing equations using a new genetic programming algorithm: application to the shear strength of reinforced concrete beams

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    [Abstract] A method based on Genetic Programming (GP) to improve previously known empirical equations is presented. From a set of experimental data, the GP may improve the adjustment of such formulas through the symbolic regression technique. Through a set of restrictions, and the indication of the terms of the expression to be improved, GP creates new individuals. The methodology allows us to study the need of including new variables in the expression. The proposed method is applied to the shear strength of concrete beams. The results show a marked improvement using this methodology in relation to the classic GP and international code procedures.Ministerio de Ciencia e Innovación; BIA2007-60197Ministerio de Ciencia e Innovación; BIA2010-21551Xunta de Galicia; 08TMT005CTXunta de Galicia; 10TMT034

    Channel-Aware Energy Optimization of OFDM Receivers Using Dynamic Precision Scaling in FPGAs

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    International audienceTo reduce the energy consumption of Orthogonal Frequency-Division Multiplexing (OFDM) systems, a new variable word-length method is presented in this paper. A simulation based approach is used: the optimized fixed-point implementation of an OFDM receiver is found for different simulated channel conditions, depending on the Signal-to-Noise Ratio (SNR) and the channel type. During the execution, the receiver estimates the channel conditions and chooses the optimum word-length to decode the received information. A realistic energy consumption of the receiver is estimated with a library that contains the energy consumption of Field-Programmable Gate Array (FPGA) basic operators depending on the bit-width, obtained from experimental data. Up to 57% of the dynamic energy can be saved using this method

    Energy-Aware Computing via Adaptive Precision under Performance Constraints in OFDM Wireless Receivers

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    International audienceTo cope with rapid variations of channel parameters , wireless receivers are designed with a significant performance margin to reach a given Bit Error Rate (BER), even for the worst-case channel conditions. Indeed, one of the steps during the design phase is the choice of the architecture bit-width, and the smallest wordlength that ensures the correct behaviour of the receiver is usually chosen. In this paper, an adaptive precision OFDM receiver is proposed. Significant energy savings come from varying at run time processing bit-width, based on estimation of channel conditions, without compromising the BER constraints. To validate the energy savings, the energy consumption of basic operators has been obtained from real measurements for different bit-widths on a FPGA and a processor using soft SIMD. Results show that up to 63% of the dynamic energy consumption can be saved using this adaptive technique

    Dynamics of genetic variability in Anastrepha fraterculus (Diptera: Tephritidae) during adaptation to laboratory rearing conditions

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    BACKGROUND: Anastrepha fraterculus is one of the most important fruit fly plagues in the American continent and only chemical control is applied in the field to diminish its population densities. A better understanding of the genetic variability during the introduction and adaptation of wild A. fraterculus populations to laboratory conditions is required for the development of stable and vigorous experimental colonies and mass-reared strains in support of successful Sterile Insect Technique (SIT) efforts. METHODS: The present study aims to analyze the dynamics of changes in genetic variability during the first six generations under artificial rearing conditions in two populations: a) a wild population recently introduced to laboratory culture, named TW and, b) a long-established control line, named CL. RESULTS: Results showed a declining tendency of genetic variability in TW. In CL, the relatively high values of genetic variability appear to be maintained across generations and could denote an intrinsic capacity to avoid the loss of genetic diversity in time. DISCUSSION: The impact of evolutionary forces on this species during the adaptation process as well as the best approach to choose strategies to introduce experimental and mass-reared A. fraterculus strains for SIT programs are discussed.Fil: Scannapieco, Alejandra Carla. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Scannapieco, Alejandra Carla. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Remis, Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Laboratorio de Genética de la Estructura Poblacional; ArgentinaFil: Juri, Marianela Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Vera, María Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia. Cátedra Terapéutica Vegetal; ArgentinaFil: Segura, Diego Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Cladera, Jorge Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Lanzavecchia, Silvia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentin

    Genetics and biology of Anastrepha fraterculus: Research supporting the use of the sterile insect technique (SIT) to control this pest in Argentina

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    Two species of true fruit flies (taxonomic family Tephritidae) are considered pests of fruit and vegetable production in Argentina: the cosmopolitan Mediterranean fruit fly (Ceratitis capitata Wiedemann) and the new world South American fruit fly (Anastrepha fraterculus Wiedemann). The distribution of these two species in Argentina overlaps north of the capital, Buenos Aires. Regarding the control of these two pests, the varied geographical fruit producing regions in Argentina are in different fly control situations. One part is under a programme using the sterile insect technique (SIT) for the eradication of C. capitata, because A. fraterculus is not present in this area. The application of the SIT to control C. capitata north of the present line with the possibility of A. fraterculus occupying the niche left vacant by C. capitata becomes a cause of much concern. Only initial steps have been taken to investigate the genetics and biology of A. fraterculus. Consequently, only fragmentary information has been recorded in the literature regarding the use of SIT to control this species. For these reasons, the research to develop a SIT protocol to control A. fraterculus is greatly needed. In recent years, research groups have been building a network in Argentina in order to address particular aspects of the development of the SIT for Anastrepha fraterculus. The problems being addressed by these groups include improvement of artificial diets, facilitation of insect mass rearing, radiation doses and conditions for insect sterilisation, basic knowledge supporting the development of males-only strains, reduction of male maturation time to facilitate releases, identification and isolation of chemical communication signals, and a good deal of population genetic studies. This paper is the product of a concerted effort to gather all this knowledge scattered in numerous and often hard-toaccess reports and papers and summarize their basic conclusions in a single publication.Fil: Cladera, Jorge Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Vilardi, Juan Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Ecología, Genética y Evolución. Genética de Población Aplicadas; ArgentinaFil: Juri, Marianela Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentina. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Ecología, Genética y Evolución. Genética de Población Aplicadas; ArgentinaFil: Paulin, Laura Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Ecología, Genética y Evolución. Genética de Población Aplicadas; ArgentinaFil: Giardini, M. Cecilia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Gómez Cendra, Paula Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Ecología, Genética y Evolución. Genética de Población Aplicadas; ArgentinaFil: Segura, Diego Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; ArgentinaFil: Lanzavecchia, Silvia Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    SEER: Safe Efficient Exploration for Aerial Robots using Learning to Predict Information Gain

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    We address the problem of efficient 3-D exploration in indoor environments for micro aerial vehicles with limited sensing capabilities and payload/power constraints. We develop an indoor exploration framework that uses learning to predict the occupancy of unseen areas, extracts semantic features, samples viewpoints to predict information gains for different exploration goals, and plans informative trajectories to enable safe and smart exploration. Extensive experimentation in simulated and real-world environments shows the proposed approach outperforms the state-of-the-art exploration framework by 24% in terms of the total path length in a structured indoor environment and with a higher success rate during exploration

    Enabling Large-scale Heterogeneous Collaboration with Opportunistic Communications

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    Multi-robot collaboration in large-scale environments with limited-sized teams and without external infrastructure is challenging, since the software framework required to support complex tasks must be robust to unreliable and intermittent communication links. In this work, we present MOCHA (Multi-robot Opportunistic Communication for Heterogeneous Collaboration), a framework for resilient multi-robot collaboration that enables large-scale exploration in the absence of continuous communications. MOCHA is based on a gossip communication protocol that allows robots to interact opportunistically whenever communication links are available, propagating information on a peer-to-peer basis. We demonstrate the performance of MOCHA through real-world experiments with commercial-off-the-shelf (COTS) communication hardware. We further explore the system's scalability in simulation, evaluating the performance of our approach as the number of robots increases and communication ranges vary. Finally, we demonstrate how MOCHA can be tightly integrated with the planning stack of autonomous robots. We show a communication-aware planning algorithm for a high-altitude aerial robot executing a collaborative task while maximizing the amount of information shared with ground robots. The source code for MOCHA and the high-altitude UAV planning system is available open source: http://github.com/KumarRobotics/MOCHA, http://github.com/KumarRobotics/air_router.Comment: 7 pages, 8 figure

    Active Metric-Semantic Mapping by Multiple Aerial Robots

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    Traditional approaches for active mapping focus on building geometric maps. For most real-world applications, however, actionable information is related to semantically meaningful objects in the environment. We propose an approach to the active metric-semantic mapping problem that enables multiple heterogeneous robots to collaboratively build a map of the environment. The robots actively explore to minimize the uncertainties in both semantic (object classification) and geometric (object modeling) information. We represent the environment using informative but sparse object models, each consisting of a basic shape and a semantic class label, and characterize uncertainties empirically using a large amount of real-world data. Given a prior map, we use this model to select actions for each robot to minimize uncertainties. The performance of our algorithm is demonstrated through multi-robot experiments in diverse real-world environments. The proposed framework is applicable to a wide range of real-world problems, such as precision agriculture, infrastructure inspection, and asset mapping in factories. A demo video can be found at https://youtu.be/S86SgXi54oU.Comment: ICRA 2023 (2023 International Conference on Robotics and Automation
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