No abstract

A successful circular economy can only exist when it relies solely on renewable energy sources. The adoption of resilient business models and the consequent redesign of legislation on all sectors are essential to ensure sustainable economic growth. Wind energy can offer clean and renewable energy with a low environmental impact. Nevertheless, waste in end of life composite materials resulting from wind turbines is a problem that needs to be addressed. Composite materials are commonly used in wind turbines due to their excellent mechanical properties, matched by low weight. Notably, the recycling technologies of such materials is limited. Material flows and estimations of end of life materials are of great importance and will convince stakeholders that markets for recycling composites are viable investments.

No abstract

Genetic variation at eleven gene loci coding for enzymes has been studied in sympatric Greek island populations of Drosophila melanogaster and D. simulans. Only two enzyme loci indicate an absolute interspecific difference. In D. melanogaster, the average number of alleles per locus was 2.37, the mean proportion of polymorphic loci 0.818, and the mean heterozygosity 0.156. The corresponding values in D. simulans were 2.09, 0.455, and 0.173 respectively. The average heterozygosity was found to be higher in the Greek island population of D. simulans than in the Hawaiian population studied by others; allelic differences were observed as well. The coefficient of genetic identity (Nei's I) between the two sibling species was found to be 0.566. A comparison of genetic similarity among Greek, American (U.S.A.) and Japanese D. melanogaster populations, estimated on the basis of allelie frequencies for nine enzymic loci, showed little difference between the populations, giving an average genetic similarity of 0.965.

The current paper presents an inclusive survey about the AC to DC and DC to DC converters for brushed DC Motor Drives. An essential number of different AC to DC and DC to DC topologies and control techniques, applied on the brushed DC motor drives are presented. This extensive literature review exposes advantages, disadvantages and limitations besides giving the basic operating principles of various topologies and control techniques.