A reliability study of the six western transmission lines maintained by EDELCA, the major power generation and transmission utility in Venezuela was completed. The main purpose of this paper was to ...estimate a set of reliability indices for each power transmission line, using probabilistic techniques such as the Markov approach and the state enumeration method for the load points system assessment. The study was performed by means of a comprehensible transmission system modeling only taking into account the assets of EDELCA from the National power system and using a reliable database specially designed. Furthermore, the adverse weather conditions were considered in terms of the regional lightning characteristics. The expected load curtailment and the expected energy not supplied indices were used to evaluate the reliability of four load points, considering until second order events. Finally, the overall performance of western transmission system of EDELCA is 99,923 %.
A complete reliability study of three large transmission substations of EDELCA, the major power generation and transmission utility in Venezuela was made.
EU coal regions Alves Dias, Patrícia; Kanellopoulos, Konstantinos; Medarac, Hrvoje ...
2018, Letnik:
29292
Journal Article
Odprti dostop
The European coal sector currently employs nearly half million people in direct and indirect activities. By 2030, it is estimated that around 160 000 direct jobs may be lost. Regional development ...based on a carefully planned restructuring process, to which renewable energy plays central role, will create new employment opportunities.
Consider a complex Hamiltonian system and an integral curve. In this paper, we give an effective and efficient procedure to put the variational equation of any order along the integral curve in ...reduced form provided that the previous one is in reduced form with an abelian Lie algebra. Thus, we obtain an effective way to check the Morales-Ramis-Simó criterion for testing meromorphic Liouville integrability of Hamiltonian systems.
The UV-initiative Hubble Space Telescope Treasury survey of Galactic globular clusters provides a new window into the phenomena that shape the morphological features of the horizontal branch (HB). ...Using this large and homogeneous catalog of UV and blue photometry, we demonstrate that the HB exhibits discontinuities that are remarkably consistent in color (effective temperature). This consistency is apparent even among some of the most massive clusters hosting multiple distinct sub-populations (such as NGC 2808, omega Cen, and NGC 6715), demonstrating that these phenomena are primarily driven by atmospheric physics that is independent of the underlying population properties. However, inconsistencies arise in the metal-rich clusters NGC 6388 and NGC 6441, where the discontinuity within the blue HB (BHB) distribution shifts ~1,000 K to 2,000 K hotter. We demonstrate that this shift is likely due to a large helium enhancement in the BHB stars of these clusters, which in turn affects the surface convection and evolution of such stars. Our survey also increases the number of Galactic globular clusters known to host blue-hook stars (also known as late hot flashers) from 6 to 23 clusters. These clusters are biased toward the bright end of the globular cluster luminosity function, confirming that blue-hook stars tend to form in the most massive clusters with significant self-enrichment.
