REPARAÇÃO E REABILITAÇÃO DE ESTRUTURAS PORTUÁRIAS COM REDUZIDO IMPACTO AMBIENTAL: O CASO DO PORTO DE ABRIGO DA ILHA DO PORTO SANTO (MADEIRA, PORTUGAL) [ Repair and rehabilitation of harbor structures with reduced environmental impact: The case of the shelter harbor of Porto Santo Island (Madeira, Portugal) ]

RESUMO: Neste trabalho, são descritas e analisadas as diversas soluções implementadas nas obras de reparação e reabilitação do porto de abrigo da Ilha do Porto Santo, no Arquipélago da Madeira, Portugal. São focados os aspectos essenciais envolvidos nos trabalhos de reabilitação, como o enquadramento climático e geográfico, os estudos preliminares realizados, a caracterização das obras e a solução de reabilitação implementada, que contribuiu para a redução do seu impacto ambiental, assim como a ordem de trabalhos e os meios necessários à sua execução. São também apresentados os resultados da aplicação da metodologia simplificada de cálculo das dimensões e do peso dos blocos de proteção e do enrocamento, bem como da espessura das diferentes camadas por estes formadas, sendo ainda discutidos os aspectos mais e menos positivos desses trabalhos de reabilitação portuária.ABSTRACT: In this paper, the different solutions implemented in the repair and rehabilitation works of the shelter harbor of Porto Santo Island, in the Archipelago of Madeira, Portugal are described and analyzed. The essential aspects involved in the rehabilitation works are focused, such as the climatic and geographical framework, the preliminary studies carried out, the characterization of the works and the rehabilitation solution implemented, which contributed to the reduction of their environmental impact, as well as the task schedule and the means for its execution. The results of the application of the simplified methodology for calculating the dimensions and weight of the protection blocks and the rockfill, as well as the thickness of the different layers formed by them are also presented, and the most positive and the less positive aspects of these harbor rehabilitation works are also discussed.

The Reduction of Directed Cyclic Graph for Task Assignment Problem

In this paper, a directed cyclic graph (DCG) is proposed as the task graph. It is undesirable and impossible to complete the task according to the constraints if the cycle exists. Therefore, an effort should be done in order to eliminate the cycle to obtain a directed acyclic graph (DAG), so that the minimum amount of time required for the entire task can be found. The technique of reducing the complexity of the directed cyclic graph to a directed acyclic graph by reversing the orientation of the path is the main contribution of this study. The algorithm was coded using Java programming and consistently produced good assignment and task schedule.