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Reynaldo Afonso Esteves; José Helvecio Martins; Wanyr Romero Ferreira. Viabilidade do reflorestamento com eucalipto para produção de carvão. Brazilian Journal of Development 2020, 6, 796 -805.
AMA StyleReynaldo Afonso Esteves, José Helvecio Martins, Wanyr Romero Ferreira. Viabilidade do reflorestamento com eucalipto para produção de carvão. Brazilian Journal of Development. 2020; 6 (1):796-805.
Chicago/Turabian StyleReynaldo Afonso Esteves; José Helvecio Martins; Wanyr Romero Ferreira. 2020. "Viabilidade do reflorestamento com eucalipto para produção de carvão." Brazilian Journal of Development 6, no. 1: 796-805.
In this article we respond to the comments made by Chavanne et al., who have questioned: (i) the name of the technique used; (ii) the ability of the system to determine both soil water content and salinity due to potential instrument biases and choice of sensor frequencies; and (iii) the procedure used to determine temperature effect on readings presented in the article “A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils” (Sensors 2015, 15, 25546–25563). We have carefully analyzed the arguments in the comment, and have concluded that they only partially affect the previous conclusions, as will be discussed in this reply. We show here that the findings and conclusions previously drawn are valid and supported by the many experiments previously conducted.
Alan Kardek Rêgo Segundo; Marco Jose Da Silva; Gustavo Medeiros Freitas; Paulo Marcos De Barros Monteiro; José Helvecio Martins. Reply to Comments: A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils, Sensors, 15, 25546–25563. Sensors 2018, 18, 1742 .
AMA StyleAlan Kardek Rêgo Segundo, Marco Jose Da Silva, Gustavo Medeiros Freitas, Paulo Marcos De Barros Monteiro, José Helvecio Martins. Reply to Comments: A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils, Sensors, 15, 25546–25563. Sensors. 2018; 18 (6):1742.
Chicago/Turabian StyleAlan Kardek Rêgo Segundo; Marco Jose Da Silva; Gustavo Medeiros Freitas; Paulo Marcos De Barros Monteiro; José Helvecio Martins. 2018. "Reply to Comments: A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils, Sensors, 15, 25546–25563." Sensors 18, no. 6: 1742.
The scarcity of drinking water affects various regions of the planet. Although climate change is responsible for the water availability, humanity plays an important role in preserving this precious natural resource. In case of negligence, the likely trend is to increase the demand and the depletion of water resources due to the increasing world population. This paper addresses the development, design and construction of a low cost system for measuring soil volumetric water content (θ), electrical conductivity (σ) and temperature (T), in order to optimize the use of water, energy and fertilizer in food production. Different from the existing measurement instruments commonly deployed in these applications, the proposed system uses an auto-balancing bridge circuit as measurement method. The proposed models to estimate θ and σ and correct them in function of T are compared to the ones reported in literature. The final prototype corresponds to a simple circuit connected to a pair of electrode probes, and presents high accuracy, high signal to noise ratio, fast response, and immunity to stray capacitance. The instrument calibration is based on salt solutions with known dielectric constant and electrical conductivity as reference. Experiments measuring clay and sandy soils demonstrate the satisfactory performance of the instrument.
Alan Kardek Rêgo Segundo; José Helvecio Martins; Paulo Marcos De Barros Monteiro; Rubens Alves De Oliveira; Gustavo Medeiros Freitas. A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils. Sensors 2015, 15, 25546 -25563.
AMA StyleAlan Kardek Rêgo Segundo, José Helvecio Martins, Paulo Marcos De Barros Monteiro, Rubens Alves De Oliveira, Gustavo Medeiros Freitas. A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils. Sensors. 2015; 15 (10):25546-25563.
Chicago/Turabian StyleAlan Kardek Rêgo Segundo; José Helvecio Martins; Paulo Marcos De Barros Monteiro; Rubens Alves De Oliveira; Gustavo Medeiros Freitas. 2015. "A Novel Low-Cost Instrumentation System for Measuring the Water Content and Apparent Electrical Conductivity of Soils." Sensors 15, no. 10: 25546-25563.
Elevated prices and lack of proper legislation and government incentives have been the main barriers in the development of the photovoltaic market in Brazil. In an attempt to overcome those barriers, a microgrid model was proposed and simulated. In the proposed microgrids, residential consumers are connected to each other to maximize the investment return by trading the surplus of generated energy among them. Different topologies and scenarios were studied from electrical energy and economic standpoints. Stochastic data of solar radiation were simulated for the city of Viçosa, Minas Gerais, Brazil, for the period of one year, considering the statistical behavior of a series over 20 years. The system output power and energy balance were calculated considering a model for photovoltaic generators and the radiation simulated data. By determining the generated energy and electrical needs of the microgrid members, the cash flow and economic feasibility were calculated. Sensitivity analyses were performed by varying economic parameters to determine situations where investment becomes feasible. This paper shows that microgrid contributes to improve the economics and the initial investments. The number of participants in a microgrid, the electricity and the equipment costs are important parameters to speed up the economic and technical feasibility process.
Gustavo Azevedo Xavier; Delly Oliveira Filho; José Helvecio Martins; Paulo Marcos De Barros Monteiro; Antônia Sônia Alves Cardozo Diniz. Simulation of Distributed Generation with Photovoltaic Microgrids—Case Study in Brazil. Energies 2015, 8, 4003 -4023.
AMA StyleGustavo Azevedo Xavier, Delly Oliveira Filho, José Helvecio Martins, Paulo Marcos De Barros Monteiro, Antônia Sônia Alves Cardozo Diniz. Simulation of Distributed Generation with Photovoltaic Microgrids—Case Study in Brazil. Energies. 2015; 8 (5):4003-4023.
Chicago/Turabian StyleGustavo Azevedo Xavier; Delly Oliveira Filho; José Helvecio Martins; Paulo Marcos De Barros Monteiro; Antônia Sônia Alves Cardozo Diniz. 2015. "Simulation of Distributed Generation with Photovoltaic Microgrids—Case Study in Brazil." Energies 8, no. 5: 4003-4023.
Durante o processo de criação de frangos de corte a fase inicial ou fase de aquecimento se caracteriza por ser este o período mais delicado devido à imaturidade fisiológica das aves. Desta forma, os fatores ambientais se destacam por inferir, de forma direta, no crescimento, no desempenho zootécnico e na mantança da vida desses animais. Objetivou-se, com base nessas considerações estudar, com este trabalho, o efeito de três diferentes sistemas de ventilação mínima (por pressão positiva, negativa e natural) sobre as variáveis ambientais (temperatura do ar, umidade relativa e velocidade do ar) de galpões de frangos de corte, durante a fase de aquecimento. De acordo com os resultados verificou-se que o sistema de aquecimento utilizado não foi satisfatório para manter a temperatura do ar e a umidade relativa dentro de padrões considerados adequados, expondo as aves, assim, a períodos de estresse térmico por frio. Em contrapartida, não ocorreram influências negativas em relação às taxas de ventilação aplicadas para os dois sistemas de ventilação positiva e negativa. A velocidade do ar também se manteve em níveis considerados não estressores para as aves, no período de aquecimento.
Irene Menegali; Ilda F. F. Tinôco; Cinara Da C. S. Carvalho; Cecília De F. Souza; José H. Martins. Comportamento de variáveis climáticas em sistemas de ventilação mínima para produção de pintos de corte. Revista Brasileira de Engenharia Agrícola e Ambiental 2013, 17, 106 -113.
AMA StyleIrene Menegali, Ilda F. F. Tinôco, Cinara Da C. S. Carvalho, Cecília De F. Souza, José H. Martins. Comportamento de variáveis climáticas em sistemas de ventilação mínima para produção de pintos de corte. Revista Brasileira de Engenharia Agrícola e Ambiental. 2013; 17 (1):106-113.
Chicago/Turabian StyleIrene Menegali; Ilda F. F. Tinôco; Cinara Da C. S. Carvalho; Cecília De F. Souza; José H. Martins. 2013. "Comportamento de variáveis climáticas em sistemas de ventilação mínima para produção de pintos de corte." Revista Brasileira de Engenharia Agrícola e Ambiental 17, no. 1: 106-113.