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Galo J.M.,State University of Maringá | Streit-Junior D.P.,Federal University of Rio Grande do Sul | Sirol R.N.,Companhia Paulista de Forca e Luz CPFL | Ribeiro R.P.,State University of Maringá | And 3 more authors.
Brazilian Journal of Biology | Year: 2011

The objective of this research was to verify the presence of spermatic abnormalities on semen of Brycon orbignyanus after cryopreservation. Semen was collected from ten four-year-old males who presented secondary reproductive characteristics for migrating fish. Sperm was evaluated for motility, vigor and spermatic morphology before and after cryopreservation. A cryoprotectant solution was made of 20 mL of yolk egg, 5.0 g of glucose and dimethyl sulfoxide diluted in distilled water (10 mL: 90 mL). The diluted semen (1:3, semen:solution) was submitted to nitrogen steam for 24 hours and then to liquid nitrogen (-196 °C) for 60 days. Cryopreservation decreased the percentage of normal spermatozoa from 62.20% to 54.60%. Consequently, the percentage of spermatozoa with secondary abnormalities increased from 8.50% to 15.00%. However, there was no difference in primary abnormalities. Both spermatic motility and vigor were decreased in cryopreserved semen compared with fresh semen. In conclusion, cryopreservation of semen of B. orbignyanus increased the percentage of secondary abnormalities and decreased the spermatic motility and vigor.

De Oliveira P.S.,University of Sao Paulo | Biasotto E.,University of Sao Paulo | Lima M.A.A.,University of Sao Paulo | Vieira J.C.M.,University of Sao Paulo | And 5 more authors.
IEEE Power and Energy Society General Meeting | Year: 2011

This paper presents a methodological analysis to increase the power transfer capability of an overhead distribution line, by changing the rated voltage from 34.5 kV to 69 kV. The distribution line chosen for analysis was modeled on ATP software, using ATPDraw interface, and was submitted to various electromagnetic transients. From the overvoltage values observed in the simulations, new computer analysis were performed using the software FLUX®, which is based on the finite element theory. FLUX® was employed to evaluate the behavior of the electrical field in different pole types of the distribution line, considering the wood crossarms and ceramic insulators. Thus, this study evaluates the computer simulations carried out and points out which poles and crossarms of the original 34.5 kV line are already able to operate on 69 kV, without changing the overhead line spacing. © 2011 IEEE.

Crispino F.,FDTE Foundation for the Technological Development of the Engineering Sciences | Magrini L.C.,FDTE Foundation for the Technological Development of the Engineering Sciences | Ogiboski L.,FDTE Foundation for the Technological Development of the Engineering Sciences | Nicoli S.,FDTE Foundation for the Technological Development of the Engineering Sciences | And 3 more authors.
2010 IEEE/PES Transmission and Distribution Conference and Exposition: Latin America, T and D-LA 2010 | Year: 2011

This paper describes the research and development results of a multi-technology and multi-platform system for the interpretation and analysis of the protection tripping in distribution substations. As part of the project it was developed a system for the analytical interpretation of the protection in order to generate tripping diagnosis of protection relays in power distribution substations. The system was designed to be suitable to different relays technologies (from electromechanical to digital), to different manufacturers and also to different communication protocols. The system get local information from the substation and data from protection relays, using a rule-based expert system (CLIPS). The purpose of the system is to analyze and interpret protection equipment tripping in a distribution substation. The system may be an important tool to assist in analyzing tripping protection events. It can provide diagnosis for proper parameterization of protection relays tripping curves. The system also recognize which function of the protection relay was activated as well as other characteristics such as the operating time, fault type with its currents, voltages and phases involved. The system may also analyze if the circuit breaker responded properly to trip commands. The laboratory results presented were obtained from different protection relays of different types, different manufacturers and different communication protocols. In addition, to simulate faults, it was used a relay testing equipment. The protection relays were arranged to simulate a feeder bay of a distribution substation, thus allowing the configuration of different power system faults for different types of relays. © 2011 IEEE.

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