3,367 research outputs found
Productive Inclusion of Smallholder Farmers in Brazil?s Biodiesel Value Chain: Programme Design, Institutional Incentives and Stakeholder Constraints
One of the principal challenges in sustainable development, especially in developing countries, is to build institutions that generate positive environmental and social externalities by helping individuals to perceive a positive relationship between self-interest and ?the common good?. Collective engagement can enable individuals to overcome self-interestedness and work toward shared goals, but ?getting the institutions right? requires an understanding of how the particular set of market and non-market relationships really work for participants. In the context of the biodiesel value chain in Brazil, this paper explores how institutional arrangements need to evolve if they are to foster the productive and sustained inclusion of small farmers and promote sustainable innovation as a regional economic development strategy, one that helps reduce social vulnerability without increasing environmental risks. The paper uses the institutional analysis and design (IAD) framework, which looks at how actors are involved in repetitive situations affected by a biophysical world, a cultural world and a set of rules, in order to understand how different institutional structures can accommodate the power of both internal and exogenous forces that shape the trajectory of sustainable innovation. After a general overview of stakeholders and policy instruments in the biodiesel programme, the paper provides a brief institutional analysis of the interaction between actors and processes, with a view to offering insights into the current effectiveness of the programme as a sustainable rural development tool. (...)Productive Inclusion of Smallholder Farmers in Brazil?s Biodiesel Value Chain: Programme Design, Institutional Incentives and Stakeholder Constraints
Structured Linearization of Discrete Mechanical Systems for Analysis and Optimal Control
Variational integrators are well-suited for simulation of mechanical systems
because they preserve mechanical quantities about a system such as momentum, or
its change if external forcing is involved, and holonomic constraints. While
they are not energy-preserving they do exhibit long-time stable energy
behavior. However, variational integrators often simulate mechanical system
dynamics by solving an implicit difference equation at each time step, one that
is moreover expressed purely in terms of configurations at different time
steps. This paper formulates the first- and second-order linearizations of a
variational integrator in a manner that is amenable to control analysis and
synthesis, creating a bridge between existing analysis and optimal control
tools for discrete dynamic systems and variational integrators for mechanical
systems in generalized coordinates with forcing and holonomic constraints. The
forced pendulum is used to illustrate the technique. A second example solves
the discrete LQR problem to find a locally stabilizing controller for a 40 DOF
system with 6 constraints.Comment: 13 page
Evaluation of wave loads on a new type of perforated caisson
Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees.A new type of perforated breakwater has been tested combining the advantages of cylindrical geometry with stepped wave energy dissipation. Thus, the new type of caisson implies a significant reduction of maximum wave forces, as well as loads transmitted to the foundation in comparison with conventional vertical breakwater and other types of perforated caissons. Starting from a brief description of the model and test results, this paper describes the development of a methodology for the estimation of maximum wave loads on this type of breakwater, in order to become a generalisable tool for predesign purposes. Construction and installation constraints of this new type of caisson are also assessed. These need to be taken into account in order to keep some advantages from the proposed design, while noting the key factors from a practical point of view.Peer ReviewedPostprint (published version
Converging Underwater and FSO Ground Communication Links
We propose a new combined underwater-atmospheric optical communication link for providing a high speed optical connectivity between onshore and sumerge systems. New average BER expressions are derived when assuming amplify-and-forward (AF) relay.Universidad de Málaga. Campus de Excelencia Internacional AndalucÃa Tech
Complementarities Between Physical Modelling and Computational Fluid Dynamics for an Ecological Continuity Project
This study presents a comparison between physical modelling and computational fluid dynamics (CFD) for investigating ecological continuity of the Poutès dam modification project. Water depth and velocity measurements have been carried out in the whole physical model. A CFD model has been built based on the geometry of the physical model. Simulations were performed using the OpenFOAM software and the InterFoam solver. Water depths and velocities have been extracted from the numerical model and compared to measurements. The agreement is very good for water depths and quite good for velocities
How Is the Internet Changing Labor Market Arrangements? Evidence from Telecommunications Reforms in Europe
This paper exploits variations in the timing of telecommunications reforms across Europe to analyze the relationship between the rise of alternative work arrangements and the emergence of the Internet. The paper evaluates whether sectors that are technologically more dependent on information and communications technologies experienced disproportionately larger changes in their employment outcomes after telecommunications reforms were introduced. The main results point to a disproportionate increase in total employment, parttime work, and home-based work among information and communications technologies–intensive sectors after the implementation of telecommunications reforms. The analysis does not find a link between the incidence of temporary employment, selfemployment, second job holding, and telecommunications reforms. The main results are robust to several specifications.Centro de Estudios Distributivos, Laborales y Sociales (CEDLAS
How Is the Internet Changing Labor Market Arrangements? Evidence from Telecommunications Reforms in Europe
This paper exploits variations in the timing of telecommunications reforms across Europe to analyze the relationship between the rise of alternative work arrangements and the emergence of the Internet. The paper evaluates whether sectors that are technologically more dependent on information and communications technologies experienced disproportionately larger changes in their employment outcomes after telecommunications reforms were introduced. The main results point to a disproportionate increase in total employment, parttime work, and home-based work among information and communications technologies–intensive sectors after the implementation of telecommunications reforms. The analysis does not find a link between the incidence of temporary employment, selfemployment, second job holding, and telecommunications reforms. The main results are robust to several specifications.Centro de Estudios Distributivos, Laborales y Sociales (CEDLAS
La observación como estrategia básica para construir explicaciones en investigación cualitativa
Fil: Lahitte, Héctor Blas. División EtnografÃa. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Sánchez Vazquez, MarÃa José. Cátedra de MetodologÃa de la Investigación y de la Ética Aplicada a la PsicologÃa Facultad de PsicologÃa. Universidad Nacional de La Plata; Argentin
Ciencias del hombre e investigación
Fil: Sánchez Vazquez, MarÃa José. Cátedra de MetodologÃa de la Investigación y de la Ética Aplicada a la PsicologÃa. Facultad de PsicologÃa. Universidad Nacional de La Plata; ArgentinaFil: Lahitte, Héctor Blas. División EtnografÃa. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; Argentin
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