Transmission network expansion planning considering repowering and reconfiguration

Transmission expansion planning (TEP) is a classic problem in electric power systems. In current optimization models used to approach the TEP problem, new transmission lines and two-winding transformers are commonly used as the only candidate solutions. However, in practice, planners have resorted to non-conventional solutions such as network reconfiguration and/or repowering of existing network assets (lines or transformers). These types of non-conventional solutions are currently not included in the classic mathematical models of the TEP problem. This paper presents the modeling of necessary equations, using linear expressions, in order to include non-conventional candidate solutions in the disjunctive linear model of the TEP problem. The resulting model is a mixed integer linear programming problem, which guarantees convergence to the optimal solution by means of available classical optimization tools. The proposed model is implemented in the AMPL modeling language and is solved using CPLEX optimizer. The Garver test system, IEEE 24-busbar system, and a Colombian system are used to demonstrate that the utilization of non-conventional candidate solutions can reduce investment costs of the TEP problem. (C) 2015 Elsevier Ltd. All rights reserved.

Artificial immune networks Copt-aiNet and Opt-aiNet applied to the reconfiguration problem of radial electrical distribution systems

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Nasalance during use of pharyngeal and glottal place of production

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Kehre: verdade e linguagem em Heidegger

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Pensamento, linguagem e língua escrita segundo a epistemologia genética: processos e construções análogos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A aprendizagem do desenho e da escrita: uma experiência com ideogramas japoneses no ensino fundamental

The aim of this paper is to gather research information and studies posted about the importance of social environment in the development of symbolic systems on children. Languages verbal, visual and written are interrelated representation systems, although each one has its own characteristics and elements. The objective of this paper is to elucidate the importance of linking the various existing types of language and therefore the importance of a coordinate approach also in the teaching-learning situations of these systems. The work also intends to disclose how thin is the line that separates writing of drawing, both of them as representative systems. As well as to show how visual information and language are intrinsically linked as thought happens by the connections between them. The work includes the report of an activity with Japanese ideograms done in the author's teacher's training at formal education. It also approaches pictographic, creative and poetic aspects of ideograms that brings up new ways of thinking and representing symbolically just like the methods of artistic language