Search results for " optimization."
showing 10 items of 2333 documents
Strategic sharing of a costly network
2012
We study minimum cost spanning tree problems for a set of users connected to a source. Prim’s algorithm provides a way of finding the minimum cost tree mm. This has led to several definitions in the literature, regarding how to distribute the cost. These rules propose different cost allocations, which can be understood as compensations and/or payments between players, with respect to the status quo point: each user pays for the connection she uses to be linked to the source. In this paper we analyze the rationale behind a distribution of the minimum cost by defining an a priori transfer structure. Our first result states the existence of a transfer structure such that no user is willing to …
The closed-form solution for a family of four-dimension nonlinear MHDS
2008
In this article we propose a method for solving a general class of four-dimension nonlinear modified Hamiltonian dynamic systems in closed form. This method may be used to study several intertemporal optimization problems sharing a common structure, which involves unbounded technological constraints as well as multiple controls and state variables. The method is developed by solving the first-order conditions associated with the planner's problem corresponding to the Lucas [1988. On the mechanics of economic development. Journal of Monetary Economics 22, 3-42] two-sector model of endogenous growth, and allows for explicitly showing the transitional dynamics of the model. Despite the externa…
Household debt and labor market fluctuations
2011
Abstract The co-movements of labor productivity with output, total hours, vacancies and unemployment have changed since the mid 1980s. This paper offers an explanation for the sharp break in the fluctuations of labor market variables based on endogenous labor supply decisions following the mortgage market deregulation. We set up a search model with efficient bargaining and financial frictions, in which impatient borrowers can take an amount of credit that cannot exceed a proportion of the expected value of their real estate holdings. When borrowers' equity requirements are low, the impact of a positive technology shock on the marginal utility of consumption is strengthened, which in turn re…
Sectoral policies cause incoherence in forest management and ecosystem service provisioning
2022
Various national policies guide forest use, but often with competing policy objectives leading to divergent management paradigms. Incoherent policies may negatively impact the sustainable provision of forest ecosystem services (FES), and forest multifunctionality. There is uncertainty among policymakers about the impacts of policies on the real world. We translated the policy documents of Finland into scenarios including the quantitative demands for FES, representing: the national forest strategy (NFS), the biodiversity strategy (BDS), and the bioeconomy strategy (BES). We simulated a Finland-wide systematic sample of forest stands with alternative management regimes and climate change. Fin…
SURATRAM - Intelligent Transport System for freight management in urban areas
2022
The project developed in the framework of this thesis is part of a more global and ambitious research program that aims at proposing a new type of goods management system in urban centers. In order to do so, the project aims to approach the management of goods from a systemic point of view, by integrating the management into the field of Intelligent Goods Transport Systems (ITS). This systemic vision of the management of goods in urban areas requires the use of electric and autonomous vehicles to ensure the tasks of delivery and collection of goods. In addition, these vehicles will be able to use the existing public transport network of the cities to move from an urban distribution center (…
Enhanced flexible algorithm for the optimization of slot filling factors in electrical machines †
2020
The continuous development in the field of industrial automation and electric mobility has led to the need for more efficient electrical machines with a high power density. The improvement of electrical machines’ slot filling factors is one of the measures to satisfy these requirements. In recent years, this topic has aroused greater interest in the industrial sector, since the evolution of the winding technological manufacturing processes allows an economically sustainable realization of ordered winding arrangements, rather than random ones. Moreover, the manufacture of electrical machines’ windings must be preceded by an accurate design phase in which it is possible to evaluate the maximu…
Optimal Operating Point Calculation for Medium Voltage Distribution Systems
2007
The paper deals with the calculation of the optimal working point of a distribution system, equipped with several distributed generators, able to operate also autonomously, i.e. disconnected from the main grid. When connected to the main grid, it appears in general convenient to assign the slack bus role to the bus that represents such a connection. The problem becomes more complex when maximum power transfer constraints through the connection must be taken into account. The adequate slack bus treatment is even more important when the optimal operating condition must refer to the condition subsequent to an intentional or unintentional disconnection from the main grid. The paper presents an …
Passive congregation based particle swam optimization (pso) with self-organizing hierarchical approach for non-convex economic dispatch
2017
This paper proposes a passive congregation based PSO with self-organizing hierarchical algorithm approach for solving the economic dispatch problem of power system, where some of the units have prohibited operating zones. This Algorithm is known to perform better than conventional gradient based optimization methods for non-convex optimization problems. Conventional PSO algorithm is a population based heuristic search, employing problem of premature convergence. In this work, an innovative approach based on the concept of passive congregation based PSO with self-organizing hierarchical approach is employed to overcome the problem of premature convergence in classical PSO method.
Econo- Environmental Dispatch Solutions for Power Systems Integrated with Renewable Energy Resources
2020
Due to the global initiatives for sustainable energy supply, the electric grids are increasingly integrated with environment-friendly and renewable energy resources. Hence, the power dispatch strategies are to be timely modified by incorporating the environmental aspects of generation along with the economic considerations. In this paper, we propose such an Econo- Environmental dispatch (EED) system for a power grids, which are integrated with renewable energy sources. The EED problem is formulated with two objective functions which aims at minimizing the unit cost of generation as well as minimizing the emissions caused during the power production. For attaining these objectives, cost and …
Training Artificial Neural Networks With Improved Particle Swarm Optimization
2020
Particle Swarm Optimization (PSO) is popular for solving complex optimization problems. However, it easily traps in local minima. Authors modify the traditional PSO algorithm by adding an extra step called PSO-Shock. The PSO-Shock algorithm initiates similar to the PSO algorithm. Once it traps in a local minimum, it is detected by counting stall generations. When stall generation accumulates to a prespecified value, particles are perturbed. This helps particles to find better solutions than the current local minimum they found. The behavior of PSO-Shock algorithm is studied using a known: Schwefel's function. With promising performance on the Schwefel's function, PSO-Shock algorithm is util…