3 resultados para Potential of zero charge

em Instituto Politécnico do Porto, Portugal


Relevância:

100.00% 100.00%

Publicador:

Resumo:

This manuscript analyses the data generated by a Zero Length Column (ZLC) diffusion experimental set-up, for 1,3 Di-isopropyl benzene in a 100% alumina matrix with variable particle size. The time evolution of the phenomena resembles those of fractional order systems, namely those with a fast initial transient followed by long and slow tails. The experimental measurements are best fitted with the Harris model revealing a power law behavior.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fractional calculus (FC) is currently being applied in many areas of science and technology. In fact, this mathematical concept helps the researches to have a deeper insight about several phenomena that integer order models overlook. Genetic algorithms (GA) are an important tool to solve optimization problems that occur in engineering. This methodology applies the concepts that describe biological evolution to obtain optimal solution in many different applications. In this line of thought, in this work we use the FC and the GA concepts to implement the electrical fractional order potential. The performance of the GA scheme, and the convergence of the resulting approximation, are analyzed. The results are analyzed for different number of charges and several fractional orders.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The concepts of smart city and social innovation in combination with the increasing use of ICT by citizens and public authorities could enhance the involvement of people on the decisions that directly affect their daily life. A case study approach was adopted to illustrate the potential of civic crowdfunding for increasing the participation and collaboration between citizens, firms and government. The analysis of two exemplary cases shows that civic crowdfunding platforms could be used by public administration to engage communities in the search of solutions to local problems. Likewise, it could be used to reinforce the community ties and to leverage the bonds among the stakeholders and the partners of the community ecosystem.