Long-Term Power Transmission Failures in Southeastern Brazil and the Geophysical Environment

2012 ◽  
Vol 33 (5) ◽  
pp. 973-989 ◽  
Author(s):  
Magda A. S. Duro ◽  
Pierre Kaufmann ◽  
Fernando C. P. Bertoni ◽  
Emilio C. N. Rodrigues ◽  
José Pissolato Filho
Keyword(s):  
Power Transmission ◽  
Southeastern Brazil ◽  
Transmission Failures

scholarly journals Trends in the Frequency of Intense Precipitation Events in Southern and Southeastern Brazil during 1960–2004

2011 ◽  
Vol 24 (7) ◽  
pp. 1913-1921 ◽  
Author(s):  
Mateus da Silva Teixeira ◽  
Prakki Satyamurty
Keyword(s):  
Extreme Rainfall ◽  
Southeastern Brazil ◽  
Extreme Rainfall Event ◽  
Southern Brazil ◽  
Extreme Rainfall Events ◽  
Rainfall Events ◽  
Annual Frequency ◽  
Long Term Trends ◽  
Increasing Trends

Abstract A new approach to define heavy and extreme rainfall events based on cluster analysis and area-average rainfall series is presented. The annual frequency of the heavy and extreme rainfall events is obtained for the southeastern and southern Brazil regions. In the 1960–2004 period, 510 (98) and 466 (77) heavy (extreme) rainfall events are identified in the two regions. Monthly distributions of the events closely follow the monthly climatological rainfall in the two regions. In both regions, annual heavy and extreme rainfall event frequencies present increasing trends in the 45-yr period. However, only in southern Brazil is the trend statistically significant. Although longer time series are necessary to ensure the existence of long-term trends, the positive trends are somewhat alarming since they indicate that climate changes, in terms of rainfall regimes, are possibly under way in Brazil.

Three new species of Collembola (Arthropoda: Hexapoda) from Central Brazilian shallow caves: side effects of long term application of environmental law on conservation

Zootaxa ◽  
2018 ◽  
Vol 4500 (1) ◽  
pp. 59 ◽  
Author(s):  
DOUGLAS ZEPPELINI ◽  
RONIERE A. BRITO ◽  
ESTEVAM C. A. LIMA
Keyword(s):  
New Species ◽  
Side Effects ◽  
Environmental Law ◽  
High Impact ◽  
Southeastern Brazil ◽  
Long Term Effects ◽  
The Law ◽  
Three New Species

Three new species of Collembola are described from small shallow caves in Southeastern Brazil: Arrhopalites glabrofasciatus sp. nov., Pseudosinella ambigua sp. nov. and Pseudosinella guanhaensis sp. nov. The species were found in surveys performed as part of the process to accomplish the permits for high impact enterprising. The change in the legislation is discussed and a suggestion is made to improve the process. The long term effects of the law resulted in the discovery of many new species and genera, most of them being (or to be) described. 

The Temporal-Spatial Evolution of the Southern Corridor of West-to-East Power Transmission Project in China

2014 ◽  
Vol 521 ◽  
pp. 485-489
Author(s):  
Hong Hao Fu ◽  
Guo Tian Cai ◽  
Dai Qing Zhao
Keyword(s):  
Power Supply ◽  
Power Plants ◽  
Power Transmission ◽  
Market Mechanism ◽  
Power Grids ◽  
Total Power ◽  
Spatial Process ◽  
Market Situation ◽  
Increasing Demand

This paper analyzes temporal and spatial process, and problems based on data between 1986 and 2010. Conclusions are as follows. Power supply of Guangdong relied more on distant outer-province power grids over time, not inner-province ones, close ones or independent power plants. This accelerating enlargement of power supply range could well satisfy its increasing power consumption. However, power production of western provinces couldnt simultaneously meet their own increasing demand and demand by Guangdong. Furthermore, total power transmission and electricity tariff were fixed by long-term framework agreements signed among governments, in which the transmission amount was too much while the tariff was too low, forcing the western provinces limiting their domestic demand without proper compensation. So the current enlarging trend of power supply range of Guangdong is unsustainable and its necessary to introduce power market mechanism through adjusting short-term total power transmission and power tariff according to the market situation.

scholarly journals The carbon sink of tropical seasonal forests in southeastern Brazil can be under threat

2020 ◽  
Vol 6 (51) ◽  
pp. eabd4548
Author(s):  
Vinícius Andrade Maia ◽  
Alisson Borges Miranda Santos ◽  
Natália de Aguiar-Campos ◽  
Cléber Rodrigo de Souza ◽  
Matheus Coutinho Freitas de Oliveira ◽  
...  
Keyword(s):  
Tropical Forests ◽  
Carbon Sink ◽  
Global Climate ◽  
Carbon Sources ◽  
Southeastern Brazil ◽  
Forest Sites ◽  
Tropical Seasonal Forest ◽  
Terrestrial Carbon Sink ◽  
Seasonal Forests

Tropical forests have played an important role as a carbon sink over time. However, the carbon dynamics of Brazilian non-Amazon tropical forests are still not well understood. Here, we used data from 32 tropical seasonal forest sites, monitored from 1987 to 2020 (mean site monitoring length, ~15 years) to investigate their long-term trends in carbon stocks and sinks. Our results highlight a long-term decline in the net carbon sink (0.13 Mg C ha−1 year−1) caused by decreasing carbon gains (2.6% by year) and increasing carbon losses (3.4% by year). The driest and warmest sites are experiencing the most severe carbon sink decline and have already moved from carbon sinks to carbon sources. Because of the importance of the terrestrial carbon sink for the global climate, policies are needed to mitigate the emission of greenhouse gases and to restore and protect tropical seasonal forests.

A Monte Carlo Model for Pitting Corrosion in Phosphor Bronze Tape Used in Underground Power Transmission Cables

CORROSION ◽  
10.5006/3347 ◽  
2020 ◽  
Vol 76 (1) ◽  
pp. 82-92
Author(s):  
Lixin Zhang ◽  
Simon Gill ◽  
Sivashangari Gnanasambandam ◽  
Maurizio Foresta ◽  
Jingzhe Pan ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Pitting Corrosion ◽  
Depth Distribution ◽  
Power Transmission ◽  
Monte Carlo Model ◽  
Probability Of Failure ◽  
Distribution Model ◽  
Pit Depth ◽  
Random Nature

Life of underground oil-filled power transmission cables used with phosphor bronze tapes is greatly reduced by pitting corrosion and hence accurate prediction of the pit growth in these tapes becomes essential. In the present work, the probability distribution of corrosion pit depth on phosphor bronze tapes is calculated using probabilistic Monte Carlo simulations and compared with the measured pit depth distribution on samples of broken tapes which have been in service for about 50 y. This Monte Carlo simulation is performed on every stable pit that nucleates, propagates, and repassivates on the metal surface. Due to the random nature of pitting corrosion, the probability of failure of this class of cables can be simulated based on the Monte Carlo model. This paper shows that the simulated pit depth distribution is very similar to the experimental data. The results demonstrate that the Monte Carlo model by Engelhardt and Macdonald can be effectively applied to long-term field data of phosphor bronze tapes, even over 50 y. In addition, the probability of failure due to pitting corrosion can be evaluated analytically, without need of conducting expensive and time-consuming experimental campaigns. Therefore, this probabilistic pit depth distribution model will be a powerful tool in the decision-making strategy for the replacement of underground power transmission cables near their end of life.

scholarly journals Assessing the validity of a food frequency questionnaire among low-income women in São Paulo, southeastern Brazil

2010 ◽  
Vol 26 (11) ◽  
pp. 2059-2067 ◽  
Author(s):  
Marly Augusto Cardoso ◽  
Luciana Yuki Tomita ◽  
Elaine Cristina Laguna
Keyword(s):  
Low Income ◽  
Food Frequency Questionnaire ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Sao Paulo ◽  
Southeastern Brazil ◽  
São Paulo ◽  
Food Frequency ◽  
Low Income Women

This study describes the validity of a food frequency questionnaire (FFQ) in 93 low-income women (20-65 years), participating in a case-control study in São Paulo, Brazil. Two FFQ (FFQ1 and FFQ2, 12 months apart) and three 24-hour dietary recalls (24hR) were conducted between 2003 and 2004 to estimate dietary intake during the past year. The Pearson correlation coefficients (crude, energy-adjusted and de-attenuated) were used for comparisons between FFQ and 24hR. The agreement between the methods was further examined by the Bland-Altman analysis. For the assessment of long-term reliability, the energy-adjusted intra-class correlation coefficients were mostly around 0.40, but higher for vitamin A and folate (0.50-0.56). Energy-adjusted, attenuation-corrected Pearson validity correlations between FFQ and DR ranged from 0.30-0.54 for macronutrients to 0.20-0.48 for micronutrients, with higher value for calcium (0.75). There were small proportions of grossly misclassified nutrient intakes, while Bland-Altman plots indicated that the FFQ is accurate in assessing nutrient intake at a group level.

scholarly journals Amphibians of the Parque Nacional da Restinga de Jurubatiba, a sandy coastal environment in southeastern Brazil

2019 ◽  
Vol 19 (2) ◽  
Author(s):  
Luiz Fernando Carmo ◽  
Ingrid Ribeiro Miguel ◽  
Pedro H. Pinna ◽  
Daniel Silva Fernandes ◽  
Manoela Woitovicz-Cardoso
Keyword(s):  
Rio De Janeiro ◽  
Coastal Environment ◽  
The State ◽  
Southeastern Brazil ◽  
Detailed Knowledge ◽  
Coastal Environments ◽  
Accurate Knowledge ◽  
First Time ◽  
Long Term Studies

Abstract: We provide an inventory checklist of the amphibians from Parque Nacional da Restinga de Jurubatiba (PNRJ), a sandy coastal environment in southeastern Brazil. As a result of three years of surveys, from August 2013 to June 2016, a total of 36 amphibians species were recorded - one Gymnophiona (Typhlonectidae) and 35 species of five anuran families: Bufonidae (2 species), Craugastoridae (1), Hylidae (21), Leptodactylidae (8), and Microhylidae (3). One specie is reported for the first time for the restinga ecosystem (Chthonerpeton braestrupi) and 24 species were recorded for the first time to the PNRJ. This result reinforces the importance of long-term studies for accurate knowledge of the biodiversity. Considering that the biodiversity of the fragments of the sandy coastal environments in the state of Rio de Janeiro is poorly known, the present study provided a more detailed knowledge about different aspects of the biodiversity in the PNRJ, contributing to the preservation of this threatened ecosystem.

Analysis on Influence of Complex Power Transmission Environment on Main Equipment Safety of JiuAn Substation

2013 ◽  
Vol 385-386 ◽  
pp. 1036-1039
Author(s):  
Tian Jiao Pu ◽  
Ai Zhong Tian ◽  
Zheng Fan ◽  
Ye Li ◽  
Dan Li
Keyword(s):  
Power Transmission ◽  
Heavy Load ◽  
Main Equipment ◽  
Equipment Safety ◽  
Transformer Substation ◽  
Complex Power ◽  
Depth Study ◽  
Electromagnetic Characteristics ◽  
The Impact

In the complex power transmission environment, the electromagnetic characteristics of the 500kV JiuAn transformer substation node will change, which will make an important impact on the main equipment of substation. This paper makes in-depth study on the impact of complex power transmission environment on the main equipment, such as high voltage, long-term heavy load, changes of run mode and forced outage. On this basis, PSCAD Software is used to simulate this model, and the simulation result is analyzed. It is significant to ensure the security of main equipment of JiuAn substation.

scholarly journals Frogs and toads of the Pedra Azul–Forno Grande Biodiversity Corridor, southeastern Brazil

Check List ◽  
2012 ◽  
Vol 8 (1) ◽  
pp. 102 ◽  
Author(s):  
Rachel Montesinos ◽  
Pedro L.V. Peloso ◽  
Diogo A. Koski ◽  
Aline P. Valadares ◽  
João Luiz Gasparini
Keyword(s):  
Threatened Species ◽  
The State ◽  
Mountain Region ◽  
Southeastern Brazil ◽  
Espírito Santo ◽  
Espirito Santo ◽  
State List

We conducted a long-term amphibian survey at the biodiversity corridor Pedra Azul-Forno Grande, in the mountain region of the state of Espírito Santo, Brazil. Sampling was conducted from April 2004 to October 2009 and we registered 43 species. Two species (Dendropsophus ruschii and Megaelosia apuana) are included in the state list of threatened species and Scinax belloni is included in the IUCN/GAA list. We provide color photographs for most species found in the region.

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