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Analysis of a Large Grounding System and Subsequent Field Test Validation Using the Fall of Potential Method  [PDF]
Huan Huang, Hualin Liu, Hong Luo, Hao Du, Yi Xing, Yexu Li, Farid P. Dawalibi, Haijun Zhou, Longhai Fu
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B240
Abstract:

This paper examines various aspects of the design process and subsequent field test measurements of a large and complex substation grounding system. The study and measurements show that soil layering and lead interference can have a significant impact on the appropriate test location that yields the exact substation ground impedance. Applying a specific percentage rule such as the 61.8% rule for uniform soils to obtain the true ground impedance may lead to unacceptable errors for large grounding systems. This poses significant problems when attempting to validate a design based on raw test data that are interpreted using approximate methods to evaluate substation ground impedance, and determine ground potential rise (GPR), touch and step voltages. Advanced measurement methodologies and modern software packages were used to obtain and effectively analyze fall of potential test data, compute fault current distribution, and evaluate touch and step voltages for this large substation. Fault current distribution between the grounding system and other metallic paths were computed to determine the portion of fault current discharged in the grounding system. The performance of the grounding system, including its GPR and touch and step voltages, has been accurately computed and measured, taking into account the impedance of the steel material used of the ground conductors and circulating currents within the substation grounding system.

Ant and termite mound coinhabitants in the wetlands of Santo Antonio da Patrulha, Rio Grande do Sul, Brazil
Diehl, E.;Junqueira, L. K.;Berti-Filho, E.;
Brazilian Journal of Biology , 2005, DOI: 10.1590/S1519-69842005000300008
Abstract: this paper reports on ant and termite species inhabiting the mounds (murundus) found in three wetland sites in santo antonio da patrulha. ants and termites were found in 100% of the mounds of two sites and in 20% of those in the third site. colonies of camponotus fastigatus were found inhabiting all the mounds, while colonies of brachymyrmex sp., linepithema sp., pheidole sp., and/or solenopsis sp. were collected in less than 30% of the mounds. in the mounds of the three sites, colonies of anoplotermes sp. and/or aparatermes sp. termites were found together with the ant colonies. another cohabiting termite species, cortaritermes sp., was found only in the mounds of one site. the results suggest that c. fastigatus is the species building the mounds, with the other species, whether ants or termites, being the inquilines.
Uso e diversidade de plantas medicinais em Santo Antonio do Leverger, MT, Brasil
Amorozo, Maria Christina de Mello;
Acta Botanica Brasilica , 2002, DOI: 10.1590/S0102-33062002000200006
Abstract: this work describes an ethnobotanical survey of medicinal plants in santo antonio do leverger municipality, mato grosso state, brazil and estimates the diversity of species with therapeutic use. adult dwellers, male and female, were interviewed and plant gathering undertaken with their assistance. voucher specimens were deposited at the herbarium rioclarense (hrcb). 228 species were identified, belonging to 73 families; 56% of the species grow spontaneously in natural and anthropically modified habitats, 41% are cultivated and 3% are purchased. diversity indexes are among the highest ones reported in literature for medicinal plants in other tropical areas. richness and diversity of spontaneous species may mirror to certain extent environmental richness and diversity, whereas for cultivated species, these measures could be linked to socio-cultural factors enhancing introduction of new plants and use information from outside the area. it is suggested that when traditional communities become more exposed to society at large, species number and knowledge about their use may at first increase, by foreign input; but, with the socio-economic changes that come about over time, plants used for therapeutic aims will be limited to the cultivated species and cosmopolite weeds.
The Research on Grounding Protection for 110kV Resistance Grounding Distribution System  [PDF]
Shan Sun, Guo Zeng, Xiaozang He, Yanping Lv, Xinyi Li
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B168
Abstract:

Using the neutral grounding method by the resistance in 110 kV system, it can limit the voltage sag and short circuit current when one-phase grounding fault occurred, but it will change the sequence of the network structure and parameters. This paper analyzes the size and distribution of zero sequence voltage and current when one-phase grounding fault occurred in the 110 kV resistance grounding system, and puts forward the grounding protection configuration setting principle of this system combining the power supplying characteristics of 110 kV distribution network. In a reforming substation as an example, the grounding protection of 110 kV lines and transformer have been set and calculated.

Uso e diversidade de plantas medicinais em Santo Antonio do Leverger, MT, Brasil  [cached]
Amorozo Maria Christina de Mello
Acta Botanica Brasilica , 2002,
Abstract: O presente trabalho tem como objetivo fazer o levantamento etnobotanico de plantas com usos terapêuticos no município de Santo Antonio do Leverger, MT, e estimar a diversidade de espécies usadas. Foram entrevistados residentes adultos de ambos os sexos, junto com os quais foram coletadas as plantas, depositadas no Herbarium Rioclarense (HRCB). Identificaram-se 228 espécies, pertencentes a 73 famílias; 56% delas crescem espontaneamente em ambientes naturais ou antropicamente modificados, 41% s o cultivadas e 3% s o compradas. Os índices de diversidade encontrados comparam-se aos mais altos registrados na literatura para plantas medicinais em outras áreas tropicais. A riqueza e diversidade das plantas espontaneas podem espelhar até certo ponto a riqueza e diversidade de espécies no ambiente, enquanto tais parametros para as espécies cultivadas estariam mais ligados a fatores sócio-culturais que promovam a introdu o de novas plantas e informa es de uso a partir de fontes externas. Sugere-se que quando comunidades tradicionais se tornam mais expostas à sociedade nacional, o número de espécies e o conhecimento acerca de seu uso podem sofrer inicialmente um acréscimo, por aportes externos; mas, com o aprofundamento do contato, e as mudan as sócio-econ micas decorrentes, a tendência será que as plantas usadas com fins terapêuticos restrinjam-se às espécies cultivadas e invasoras cosmopolitas.
Larvas de nematóides de importancia zoonótica encontradas em traíras (Hoplias malabaricus bloch, 1794) no município de Santo Antonio do Leverger, MT
Barros, L.A.;Moraes Filho, J.;Oliveira, R.L.;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2007, DOI: 10.1590/S0102-09352007000200042
Abstract: in order to investigate the prevalence of nematode larvae with zoonotical importance in trairas (hoplias malabaricus), necropsy exams were done 30 specimes from santo antonio do leverger, mato grosso, brazil. these fishes were collected during drought time and two different nematodes larvae were found - contracaecum sp. and eustrongylides sp. - presenting the following prevalence: contracaecum sp., 73% and eustrongylides sp., 33%.
Composition and trophic structure of the ichthyofauna from a stream downriver from Santo Antonio Falls in the Madeira River, Porto Velho, RO
Araújo, Túlio Raimundo de;Ribeiro, Ariana Cella;Doria, Carolina Rodrigues da Costa;Torrente-Vilara, Gislene;
Biota Neotropica , 2009, DOI: 10.1590/S1676-06032009000300001
Abstract: belmont stream is the main tributary of the madeira river in the area immediately downriver from the santo antonio fall. samplings were carried out using gill nets in the mouth of this stream between may 2005 and april 2006 and resulted in a list of 74 species. the analyses included values of composition, constancy of occurrence, species richness, abundance, catch per unit of effort and trophic structure about the ten most abundant species. characiformes and siluriformes were dominant order in the samples and curimatidae (popularly known as "branquinhas") was the most abundant family, represented by psectrogaster rutiloides (32.57% of the collected specimens), potamorhina altamazonica (10.72%), and potamorhina latior (7.79%). the most of species were considered accessory and accidental and richness suggests high values in the rising and high water. belmont maybe considered as a moderate richness when compared to those found for others amazon rivers. detritivorous fishes composed 60% of the assemblage and the constancy of the most abundant species of this family suggests belmont as an important area to these migratory fishes.
Grounding Systems for Power Supply Facilities  [PDF]
Vladimir Anatolevich Konusarov, Evgeniy Alekseevich Shutov, Tatyana Evgenievna Turukina
Energy and Power Engineering (EPE) , 2019, DOI: 10.4236/epe.2019.111001
Abstract: The goal of this work is creation of optimal grounding model at the substation 10/0.4 kV of the urban power distribution network. The electric current can pose a major threat to the man’s life and health. In addition to pose a threat for health, the rise of the short circuit, as a consequence of insulation faults, poses a threat to retirement of electric systems and fire risks. The reliable grounding system design has significant implications for protection of human being as well as for electrical facility protection. The set objective was performed on the base of analytical and software-based methods. Analytical method gives a qualitative indication at each step in analysis. It also allows evaluating the values effect on the result, but the method is not susceptible of tolerable accuracy, that is why analytical method serves as initial approximation in differentiating. Specified estimation can be performed in such software package as MATLAB or ETAP. Software-based estimation is based on the finite element method (FEM), the main advantage of which is the ability to create different forms of grounding and allows obtaining distribution graphs of the step potential on the earth’s surface and touch potential. The calculation results in comparison of analytical and software-based methods taking into account the grounding optimization. There are conclusions on the most effective ground network.
Necessity Of ABG Analysis In HPS
Kalantari M,Raeisosadat MA,Ahmadi J,Nahvi H
Tehran University Medical Journal , 2005,
Abstract: Background: The purpose of this study is to determine the incidence of electrolyte and ABG abnormalities in infants with HPS and also we evaluate other parameters of the study. Materials and Methods: This descriptive study covers 161 infants with HPS hospitalized in children Medical center of Tehran university underwent surgical repair from march 1996 to march 2002 . Results & Conclusion: The results indicated that Hypokalemic metabolic alkalosis had occurred in 40% of patients. The sex ratio was 3/1 =M/F and the most time of presentation was between 15t and 5st week and the most presenting sign was vomiting. Clinical icter happened to be found in 15% of patients. The incidence of accompanying anomalies was 9% and olive sign was palpable in 40%. The best way for evaluating and diagnosis was sonography. The mean period to begin postoperative feeding was 30 hours' no complication related to option was reported after operation.
Duas ou três coisas sobre Antonio Candido
Musse, Ricardo;
Trans/Form/A??o , 1995, DOI: 10.1590/S0101-31731995000100005
Abstract: the aim of this paper is to discuss the connection between two basic traces grounding the originality of antonio candido's literary criticism: firstly, its insertion into the mainstraim of "western marxism" and, secondly, into national (brasilian) tradition.
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