for Journals by Title or ISSN
for Articles by Keywords

Publisher: SciELO   (Total: 715 journals)

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

        1 2 3 4 | Last   [Sort by number of followers]   [Restore default list]

Showing 1 - 200 of 715 Journals sorted alphabetically
ABCD. Arquivos Brasileiros de Cirurgia Digestiva     Open Access   (Followers: 2, SJR: 0.207, CiteScore: 1)
ACIMED     Open Access   (Followers: 1)
Acta Agronómica     Open Access  
Acta Amazonica     Open Access   (Followers: 5, SJR: 0.36, CiteScore: 1)
Acta Bioethica     Open Access   (SJR: 0.196, CiteScore: 0)
Acta Botanica Brasilica     Open Access   (Followers: 3, SJR: 0.325, CiteScore: 1)
Acta botánica mexicana     Open Access   (Followers: 1, SJR: 0.212, CiteScore: 0)
Acta Cirurgica Brasileira     Open Access   (SJR: 0.395, CiteScore: 1)
Acta Limnologica Brasiliensia     Open Access   (Followers: 3, SJR: 0.28, CiteScore: 1)
Acta Literaria     Open Access   (Followers: 3, SJR: 0.1, CiteScore: 0)
Acta Medica Colombiana     Open Access   (Followers: 1)
Acta Médica Costarricense     Open Access   (Followers: 2)
Acta Neurológica Colombiana     Open Access   (Followers: 2)
Acta Ortopédica Brasileira     Open Access   (Followers: 1, SJR: 0.343, CiteScore: 1)
Acta Paulista de Enfermagem     Open Access   (Followers: 2, SJR: 0.275, CiteScore: 1)
Acta Pediátrica Costarricense     Open Access   (Followers: 1)
Acta Scientiarum. Agronomy     Open Access   (Followers: 7, SJR: 0.431, CiteScore: 1)
Acta zoológica mexicana     Open Access  
Actualidades Biológicas     Open Access   (Followers: 1)
African Human Rights Law J.     Open Access   (Followers: 18)
African Natural History     Open Access   (Followers: 2, SJR: 0.198, CiteScore: 1)
Afro-Asia     Open Access  
Ágora - studies in psychoanalytic theory     Open Access   (Followers: 3, SJR: 0.132, CiteScore: 0)
Agricultura Tecnica     Open Access   (Followers: 5)
Agrociencia     Open Access   (Followers: 1, SJR: 0.2, CiteScore: 0)
Agrociencia Uruguay     Open Access  
Agronomía Mesoamericana     Open Access  
Aisthesis     Open Access   (Followers: 6, SJR: 0.106, CiteScore: 0)
Alea : Estudos Neolatinos     Open Access   (Followers: 2, SJR: 0.1, CiteScore: 0)
Alfa : Revista de Linguística     Open Access  
Alpha (Osorno)     Open Access   (SJR: 0.138, CiteScore: 0)
Ambiente & sociedade     Open Access   (Followers: 3, SJR: 0.235, CiteScore: 0)
Ambiente & Agua : An Interdisciplinary J. of Applied Science     Open Access   (Followers: 1, SJR: 0.263, CiteScore: 1)
Ambiente Construído     Open Access   (Followers: 1)
América Latina en la historia económica     Open Access   (Followers: 2, SJR: 0.134, CiteScore: 0)
Anais Brasileiros de Dermatologia     Open Access   (Followers: 3, SJR: 0.52, CiteScore: 1)
Anais da Academia Brasileira de Ciências     Open Access   (Followers: 2, SJR: 0.418, CiteScore: 1)
Anais do Museu Paulista : História e Cultura Material     Open Access   (Followers: 1)
Anales de Medicina Interna     Open Access   (Followers: 1)
Anales del Instituto de la Patagonia     Open Access  
Anales del Sistema Sanitario de Navarra     Open Access   (Followers: 1, SJR: 0.157, CiteScore: 0)
Análise Psicológica     Open Access   (Followers: 1, SJR: 0.16, CiteScore: 0)
Análise Social     Open Access   (Followers: 2, SJR: 0.16, CiteScore: 0)
Andean geology     Open Access   (Followers: 9, SJR: 0.674, CiteScore: 1)
Antipoda. Revista de Antropología y Arqueología     Open Access   (Followers: 5, SJR: 0.135, CiteScore: 0)
Anuario Colombiano de Historia Social y de la Cultura     Open Access   (SJR: 0.1, CiteScore: 0)
Anuario de Historia Regional y de las Fronteras     Open Access  
Apuntes : Revista de Estudios sobre Patrimonio Cultural - J. of Cultural Heritage Studies     Open Access   (Followers: 6)
Archivos de Medicina Veterinaria     Open Access   (Followers: 1, SJR: 0.194, CiteScore: 0)
Archivos de Neurociencias     Open Access   (Followers: 3, SJR: 0.111, CiteScore: 0)
Archivos de Pediatria del Uruguay     Open Access   (Followers: 3)
Archivos de Zootecnia     Open Access   (Followers: 1, SJR: 0.202, CiteScore: 0)
Archivos Españoles de Urología     Open Access   (SJR: 0.178, CiteScore: 0)
Argos     Open Access   (Followers: 1)
ARQ     Open Access   (Followers: 4, SJR: 0.113, CiteScore: 0)
Arquitectura y Urbanismo     Open Access   (Followers: 3)
Arquivo Brasileiro de Medicina Veterinária e Zootecnia     Open Access   (SJR: 0.248, CiteScore: 0)
Arquivos Brasileiros de Cardiologia     Open Access   (Followers: 1, SJR: 0.381, CiteScore: 1)
Arquivos Brasileiros de Endocrinologia e Metabologia     Open Access  
Arquivos Brasileiros de Oftalmologia     Open Access   (SJR: 0.518, CiteScore: 1)
Arquivos de Gastroenterologia     Open Access   (Followers: 1, SJR: 0.396, CiteScore: 1)
Arquivos de Medicina     Open Access  
Arquivos de Neuro-Psiquiatria     Open Access   (SJR: 0.448, CiteScore: 1)
Arquivos do Instituto Biológico     Open Access   (Followers: 1)
Arquivos Internacionais de Otorrinolaringologia     Open Access  
ARS     Open Access   (Followers: 3)
Atenea (Concepción)     Open Access   (SJR: 0.112, CiteScore: 0)
Atmósfera     Open Access   (Followers: 2, SJR: 0.449, CiteScore: 1)
Audiology - Communication Research     Open Access   (Followers: 9)
Avaliação : Revista da Avaliação da Educação Superior (Campinas)     Open Access  
Avances en Odontoestomatologia     Open Access   (Followers: 1, SJR: 0.105, CiteScore: 0)
Avances en Periodoncia e Implantología Oral     Open Access   (Followers: 1)
Bakhtiniana : Revista de Estudos do Discurso     Open Access   (SJR: 0.103, CiteScore: 0)
BAR. Brazilian Administration Review     Open Access   (Followers: 1, SJR: 0.137, CiteScore: 0)
Biota Neotropica     Open Access   (SJR: 0.381, CiteScore: 1)
Biotecnología Aplicada     Open Access   (SJR: 0.146, CiteScore: 0)
Biotecnología en el Sector Agropecuario y Agroindustrial     Open Access  
Boletim de Ciências Geodésicas     Open Access   (SJR: 0.188, CiteScore: 0)
Boletim do Museu Paraense Emílio Goeldi. Ciências Humanas     Open Access   (Followers: 1, SJR: 0.238, CiteScore: 0)
Boletin Chileno de Parasitologia     Open Access  
Boletín de Filología     Open Access  
Boletín de la Sociedad Botánica de México     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Boletín de la Sociedad Geológica Mexicana     Open Access   (SJR: 0.291, CiteScore: 1)
Boletín del Museo Chileno de Arte Precolombino     Open Access   (Followers: 1, SJR: 0.233, CiteScore: 0)
Bosque     Open Access   (Followers: 2, SJR: 0.29, CiteScore: 1)
Bragantia     Open Access   (Followers: 2, SJR: 0.555, CiteScore: 1)
Brazilian Archives of Biology and Technology     Open Access   (Followers: 3, SJR: 0.281, CiteScore: 1)
Brazilian Dental J.     Open Access   (Followers: 2, SJR: 0.476, CiteScore: 1)
Brazilian J. of Biology     Open Access   (Followers: 3, SJR: 0.523, CiteScore: 1)
Brazilian J. of Chemical Engineering     Open Access   (Followers: 4, SJR: 0.395, CiteScore: 1)
Brazilian J. of Food Technology     Open Access   (Followers: 3, SJR: 0.206, CiteScore: 0)
Brazilian J. of Medical and Biological Research     Open Access   (SJR: 0.611, CiteScore: 2)
Brazilian J. of Microbiology     Open Access   (Followers: 3, SJR: 0.63, CiteScore: 2)
Brazilian J. of Oceanography     Open Access   (Followers: 1, SJR: 0.425, CiteScore: 1)
Brazilian J. of Oral Sciences     Open Access   (Followers: 1, SJR: 0.131, CiteScore: 0)
Brazilian J. of Physical Therapy     Open Access   (SJR: 0.802, CiteScore: 2)
Brazilian J. of Plant Physiology     Open Access   (Followers: 3, SJR: 1.178, CiteScore: 3)
Brazilian J. of Veterinary Research and Animal Science     Open Access   (Followers: 8, SJR: 0.225, CiteScore: 0)
Brazilian Oral Research     Open Access  
Brazilian Political Science Review     Open Access   (Followers: 1)
Caderno CRH     Open Access   (Followers: 3, SJR: 0.233, CiteScore: 0)
Caderno de Estudos     Open Access  
Cadernos CEDES     Open Access   (Followers: 1, SJR: 0.119, CiteScore: 0)
Cadernos de Pesquisa     Open Access   (Followers: 2, SJR: 0.183, CiteScore: 0)
Cadernos de Saúde Pública     Open Access   (Followers: 1, SJR: 0.568, CiteScore: 1)
Cadernos de Tradução     Open Access  
Cadernos Metrópole     Open Access   (Followers: 1)
Cadernos Nietzsche     Open Access  
Cadernos Pagu     Open Access   (SJR: 0.356, CiteScore: 0)
Cadernos Saúde Coletiva     Open Access   (Followers: 1)
Caldasia     Open Access   (SJR: 0.195, CiteScore: 0)
Calidad en la educación     Open Access   (Followers: 1)
Cerâmica     Open Access   (Followers: 5, SJR: 0.186, CiteScore: 0)
CES Medicina     Open Access  
Chilean J. of Agricultural Research     Open Access   (Followers: 1, SJR: 0.377, CiteScore: 1)
Chungara (Arica) - Revista de Antropologia Chilena     Open Access   (Followers: 1, SJR: 0.565, CiteScore: 1)
Ciência & Educação (Bauru)     Open Access  
Ciência & Saúde Coletiva     Open Access   (Followers: 2, SJR: 0.566, CiteScore: 1)
Ciência Animal Brasileira     Open Access   (Followers: 1, SJR: 0.216, CiteScore: 0)
Ciência da Informação     Open Access   (Followers: 1, SJR: 0.121, CiteScore: 0)
Ciencia del suelo     Open Access   (Followers: 2)
Ciência e Agrotecnologia     Open Access   (SJR: 0.383, CiteScore: 1)
Ciencia e Cultura     Open Access   (Followers: 1)
Ciencia e investigación agraria     Open Access   (Followers: 1, SJR: 0.211, CiteScore: 0)
Ciencia forestal en México     Open Access  
Ciência Rural     Open Access   (Followers: 2, SJR: 0.337, CiteScore: 1)
Ciencia y Enfermeria - Revista Iberoamericana de Investigacion     Open Access   (Followers: 3, SJR: 0.158, CiteScore: 0)
Ciencias Marinas     Open Access   (Followers: 2, SJR: 0.414, CiteScore: 1)
Ciencias Psicológicas     Open Access  
Cirugia Plastica Ibero-Latinoamericana     Open Access   (SJR: 0.166, CiteScore: 0)
CLEI Electronic J.     Open Access  
Clínica y Salud     Open Access   (SJR: 0.173, CiteScore: 0)
Clinics     Open Access   (SJR: 0.536, CiteScore: 1)
CoDAS     Open Access   (SJR: 0.267, CiteScore: 0)
Computación y Sistemas     Open Access   (SJR: 0.226, CiteScore: 1)
Comuni@cción     Open Access  
Comunicación y sociedad     Open Access   (Followers: 2, SJR: 0.327, CiteScore: 0)
Contaduría y Administración     Open Access   (SJR: 0.219, CiteScore: 0)
Contexto Internacional     Open Access  
Convergencia     Open Access   (Followers: 3, SJR: 0.196, CiteScore: 0)
Correo Científico Médico     Open Access  
Corrosão e Protecção de Materiais     Open Access  
Crop Breeding and Applied Biotechnology     Open Access   (Followers: 3, SJR: 0.609, CiteScore: 1)
Cuadernos de Economía     Open Access   (Followers: 2)
Cuadernos de Economia - Latin American J. of Economics     Open Access   (Followers: 2)
Cuadernos de Historia     Open Access   (Followers: 1)
Cuadernos de Historia de la Salud Publica     Open Access  
Cuadernos de Medicina Forense     Open Access   (Followers: 2, SJR: 0.1, CiteScore: 0)     Open Access   (SJR: 0.38, CiteScore: 0)
Cubo. A Mathematical J.     Open Access  
Cuicuilco     Open Access   (Followers: 1)
Cultivos Tropicales     Open Access   (Followers: 1)
Culturales     Open Access   (Followers: 3)
Dados - Revista de Ciências Sociais     Open Access   (SJR: 0.37, CiteScore: 0)
De Jure     Open Access   (Followers: 1)
DELTA : Documentação de Estudos em Lingüística Teórica e Aplicada     Open Access   (SJR: 0.133, CiteScore: 0)
Dementia & Neuropsychologia     Open Access   (Followers: 8, SJR: 0.205, CiteScore: 0)
Dental Press J. of Orthodontics     Open Access   (Followers: 2, SJR: 0.489, CiteScore: 1)
Desacatos     Open Access   (Followers: 1)
Desarrollo y Sociedad     Open Access   (Followers: 3, SJR: 0.109, CiteScore: 0)
Diálogo Andino - Revista de Historia, Geografía y Cultura Andina     Open Access   (SJR: 0.116, CiteScore: 0)
Diánoia     Open Access   (Followers: 1)
Dimensión Empresarial     Open Access  
Dynamis : Acta Hispanica ad Medicinae Scientiarumque Historiam Illustrandam     Open Access   (Followers: 2, SJR: 0.131, CiteScore: 0)
e-J. of Portuguese History     Open Access   (Followers: 2, SJR: 0.101, CiteScore: 0)
Eclética Química     Open Access   (Followers: 1)
Ecología en Bolivia     Open Access  
Economia Aplicada     Open Access   (SJR: 0.208, CiteScore: 0)
Economia e Sociedade     Open Access  
EconoQuantum     Open Access  
Educação & Sociedade     Open Access   (Followers: 3)
Educação e Pesquisa     Open Access   (Followers: 1, SJR: 0.163, CiteScore: 0)
Educação em Revista     Open Access  
Educación Matemática     Open Access  
Educación Médica     Open Access   (Followers: 1, SJR: 0.236, CiteScore: 0)
Educación Médica Superior     Open Access   (Followers: 1, SJR: 0.237, CiteScore: 0)
Educación y Educadores     Open Access  
Educar em Revista     Open Access  
EDUMECENTRO     Open Access  
En-Claves del pensamiento     Open Access   (Followers: 1, SJR: 0.194, CiteScore: 0)
Encuentros     Open Access  
Ene : Revista de Enfermería     Open Access  
Enfermería Global     Open Access   (Followers: 3, SJR: 0.165, CiteScore: 0)
Enfermería Nefrológica     Open Access   (Followers: 1, SJR: 0.198, CiteScore: 0)
Enfoques     Open Access  
Engenharia Agrícola     Open Access   (SJR: 0.305, CiteScore: 1)
Engenharia Sanitaria e Ambiental     Open Access   (SJR: 0.218, CiteScore: 0)
Ensaio Avaliação e Políticas Públicas em Educação     Open Access   (Followers: 1, SJR: 0.254, CiteScore: 0)
Entomologia y Vectores     Open Access   (Followers: 2)
Escritos de Psicología : Psychological Writings     Open Access   (Followers: 2)
Estudios Atacameños     Open Access   (Followers: 2, SJR: 0.446, CiteScore: 1)
Estudios Constitucionales     Open Access   (Followers: 5, SJR: 0.319, CiteScore: 0)
Estudios de Cultura Maya     Open Access   (Followers: 2, SJR: 0.272, CiteScore: 0)
Estudios de Economía     Open Access   (SJR: 0.121, CiteScore: 0)
Estudios de historia moderna y contemporánea de México     Open Access   (SJR: 0.101, CiteScore: 0)
Estudios Filologicos     Open Access   (SJR: 0.107, CiteScore: 0)
Estudios Fronterizos     Open Access   (Followers: 1)
Estudios internacionales     Open Access   (Followers: 5)
Estudios Pedagogicos (Valdivia)     Open Access   (Followers: 1, SJR: 0.338, CiteScore: 0)

        1 2 3 4 | Last   [Sort by number of followers]   [Restore default list]

Journal Cover
Engenharia Agrícola
Journal Prestige (SJR): 0.305
Citation Impact (citeScore): 1
Number of Followers: 0  

  This is an Open Access Journal Open Access journal
ISSN (Print) 0100-6916
Published by SciELO Homepage  [715 journals]

    • Abstract: ABSTRACT The bioclimatic architecture can contribute significantly to moderate thermal environment of agricultural installations, reducing the energy input used in the air conditioning. The present article presents the results of a diagnosis made in packing houses of table grapes, located in a semi - arid region in the Brazilian Northeast. The objective was to verify which strategies of the bioclimatic architecture were applied in the buildings, and also, to propose recommendations for future projects. The methodology consisted of the elaboration of a checklist, from the application of the Mahoney Method and the Brazilian Bioclimatic Zoning, considering Petrolina - PE climate. The checklist was applied in twenty-five packing houses, of three different sizes. It was concluded that the bioclimatic architectural strategies were applied in an isolated way in the buildings. Therefore, the bioclimatic architectural strategies were not effective in the thermal efficiency of the buildings, and the packing houses of small rural producers were the most inappropriate.

    • Abstract: ABSTRACT The objectives of this study were to evaluate the thermal comfort and the similitude between prototypes and reduced models, using non-conventional coverage with green roof and expanded clay aggregate, supported on wood frame structure. For this, were determined the Black Globe Temperature and Humidity Index (BGHI), the Human Discomfort Index (HDI), Effective Temperature (ET), Air Temperature (Tair) and Radiant Thermal Load (RTL), from March 2013 to December 2014. The results showed that there were no statistical differences to 5% significance in predicting heat indices between the prototypes and models. Observing all indexes simultaneously, it was observed that January was the month what led to the worst heat conditions, while June and July showed the worst cold conditions. It can be concluded that the use of reduced models is possible (1:2) compared to the prototype (1:1), with green roofs and expanded clay as covering element, for the prediction of thermal indexes, minimizing construction costs and use of spaces.

    • Abstract: ABSTRACT The assessment of land use and occupation is essential for predicting soil loss due to water erosion. The objective of this study was to determine criteria for monitoring soil loss in agricultural areas using the Universal Soil Loss Equation (USLE). Soil loss data were intersected with USLE factors and slope using geoprocessing techniques for the Samambaia River watershed, located in Cristalina, Goiás state, Brazil. A slope of 3% to 8% was found in approximately 50% of the study area. However, mean soil losses <10 t ha-1 year-1 were observed in slopes ≤ 3%, where the mean soil length (L) and slope steepness (S) were ≤2 and 0.2, respectively. The intersection of soil loss data with USLE factors was useful for identifying criteria for monitoring soil loss. The mean topographic factor (LS) in non-irrigated crops, pasture, and silviculture was 0.4 ± 0.4, 0.4 ± 0.7, and 2.2 ± 2.6, respectively. Therefore, LS values adequately indicated the type of land use and occupation considering that only silviculture could maintain soil losses below the tolerable limit of 10 t ha-1 year-1 for an LS mean of 2.2.

    • Abstract: ABSTRACT The objective of this study was to regionalize 7-day 10-year low flows, long-term annual mean, and 90% and 95% permanence flows from Piquiri (PR) river basin. The following regionalization methods were adopted: Traditional, Linear interpolation, Chaves, Modified linear interpolation, and Modified Chaves. The equations obtained by the Traditional method, adding main river length or drainage density as independent variables, significantly improved R2 equations value. Streamflow forecasting by Linear Interpolation and Chaves methods were as good as those provided by the Traditional Method, thus, these methods could be applied to Piquiri River basin, especially when drainage area is the only available spatial information.

    • Abstract: ABSTRACT Net radiation (Rn) of reference surface is important information that has many applications, but its measurement is rare due to the high cost of the sensor and the complexity involved on the measurement. Therefore, estimate Rn from another variable is desirable, as from solar radiation (Rs); however, standard methods used are complex, making interesting the use of simplified methodologies. Considering these aspects, the present study aimed to set two empirical methods to estimate Rn from Rs for Dourados region, Mato Grosso do Sul, Brazil. One method was based on mathematical modeling (Gauss Method). The other one was a more simplified and practical approach (Practical Method) comprising the determination of fixed monthly conversion factors. It was used daily Rs data of a 12-years database. With these, there were estimated Rn values by the standard method recommended by FAO. Gauss Method was set using Table Curve 2D 5.01 software. Modeling consisted in defining the values of the equation parameters. On Practical Method, we developed monthly coefficients of the ratio Rn/Rs. In order to validate both methods it was measured Rs and Rn during two years using high precision sensors. Both estimating methods showed satisfactory results, with relative mean absolute error values lower than 5.8%.

    • Abstract: ABSTRACT Evaporation rates in reservoirs influence the volume of water available for multiple uses. Thus, the objective of this study was to estimate the evaporation rates and the evaporated volumes per unit time in the Tucuruí-PA and Lajeado-TO reservoirs based on the methods in Linacre (1993), Kohler et al. (1955), Morton (1983), Bruin & Keijman (1979) and Penman (1948) method was adopted as the standard. The mean annual evaporation rates in the Tucuruí and Lajeado reservoirs, estimated by the Penman method, were similar, with values of 1,784 mm and 1,882 mm, respectively. None of the alternative analyzed methods could be used to estimate the mean annual evaporation in the Tucuruí and Lajeado reservoirs and could not replace the Penman method. However, the Linacre (1993) and Bruin & Keijman (1979) methods could be used to estimate monthly evaporation during the dry season in Tucuruí. The mean evaporated volume per unit time and the mean net evaporated volume per unit time in the Tucuruí reservoir correspond to 120% and 50%, respectively, of the total water demand in the Tocantins-Araguaia region, while the mean evaporated volume per unit time and the mean net evaporated volume per unit time in the Lajeado reservoir correspond to 120% and 50%, respectively, of the total water demand in the basin.

    • Abstract: ABSTRACT The aim of this study was to evaluate drip irrigation as a process, by monitoring the average flow applied by the emitter using tools of statistical quality control. Four kinds of drippers were selected, two inline labyrinth type and two online where one of the inline emitters was not self-compensating and the other, self-compensating emitter. The system was installed in the field and tested for 85 hours, using three kinds of treated domestic sewage effluents and tap water. The system was under statistical control when the emitters were new, however none of the drippers reaches the manufacturer's specification for average flow. The online drippers showed more dispersion for individual flow measurements and the non-self-compensating inline dripper was more accurately for this variable. After the end of experiment, irrigation process was not under statistical control for any kind of emitter. When using treated wastewater effluents for irrigation we recommend a first evaluation before 7 working hours, to implement appropriated correcting procedures to reduce clogging and as a result, maintain the process quality.
           RIVER BASIN

    • Abstract: ABSTRACT Hydrological models are becoming more and more widespread, mainly due to their capacity to simulate the impact of environmental changes on water resources. In this way, the aim of this study was to calibrate and validate the SWAT model for the soil and climatic conditions of the Mucuri River Basin, located in the Northeast region of the States of Minas Gerais, Brazil. The SWAT-CUP software module SUFI2 was used to analyze the sensitivity, calibration and validation of the model. The calibration was performed in an intermediate fluviometric station and the validation in five other located: three upstream, one downstream and one independent from the calibration point. It was evidenced for the study area that the parameters referring to the basic flow processes were more sensitive. The model obtained a good adjustment with an overestimate tendency of 15%. In general, the SWAT model, using SWAT-CUP was good and adequate in terms of its calibration performance and validation of the flow simulation in the Mucuri River Basin by the determination coefficients, Nash-Suttclife efficiency and percentage of trend.

    • Abstract: ABSTRACT Assess the physical quality of agricultural soils it is important to establish the management more adequate for plant growth. In this study, the soil water retention curve and S index as indicators of soil physical quality were evaluated in five integrated production systems in the following forestry arrangements: Eucalyptus in a single line, double line and triple line (Eucalyptus I, II and III respectively), Balsa in triple line and Teak triple line. The density and arrangement of forest trees influence the soil physical properties. Less soil water retention was observed in the Teak and Balsa wood systems in the layers 0-0.10 and 0.10-0.20 m. The field capacity, permanent wilting point, and available water were lower under the projection from the treetops, providing less soil water retention at this site. This position suffers more influence of the animal's footstep, having greater alterations on the soil structure. Integrated production systems showed poor soil structural quality based on the S index, averaging 0.034 and 0.035 for layers 0-0.10 and 0.10-0.20 m respectively.

    • Abstract: ABSTRACT This study demonstrates using remote sensing, geographic information systems and multivariate statistics to study water quality in an agricultural watershed. The monitoring of water quality in the watershed of Lontras's river in the southwestern region of the State of Paraná had been done in 2012 and 2013 with a multi-parameter probe in ten sites that were defined upstream and downstream watershed, during four different seasons. Mosaicked images were used from Google Earth, Digital Elevation Model and soil types of maps, defined as the explanatory variables. The definition of the areas of influence and multivariate statistical techniques, particularly the Redundancy Analysis (RDA), were used for the correlation between variables. In a spring area, located upstream watershed, the contribution on water quality variation has gotten smaller, when compared with the other monitoring sites. There was interference in water quality in downstream sites that has become greater due to the effects of diffuse pollution. The RDA enabled synthesizes the data variability structure and the relationship of multidimensional variables. These statistical techniques added to products resulting from the GIS contributed to a better understanding of the variation of water quality in the watershed.

    • Abstract: ABSTRACT Farmers are seeking pesticide treatments with lower application rates and higher travel speeds. However, this can lead to a poor quality of the application. The aim of this study was to evaluate the spray deposition on soybean crop and the droplet spectra using different application rates and speeds. The experiment was conducted in soybean (R5 stage), M 6410 IPRO variety. Six treatments involving two application rates (80 and 150 L ha-1) and three speeds (10, 15 and 20 km h-1) were evaluated through a self-propelled sprayer. A characterization study of the spray droplets was conducted through the evaluation of water sensitive papers. The spray deposition study was carried out. For this, a marker was added to the application to be detected by absorbance in spectrophotometry. The use of spray nozzles with higher nominal flow, as well as lower pressures, produced droplets of larger sizes. The application rate of 80 L ha-1 provided equal and higher spray retention in the lower and upper leaves of the plants, respectively. The three speeds did not influence the deposition on soybean plants.
  • Failure mode and effect analysis (FMEA) in mechanized harvest of sugarcane

    • Abstract: ABSTRACT The quality control is used for the evaluation of processes and products, and it is important to detect and reduce variability and in operations management can be applied in mechanized harvesting of sugarcane billets. In this sense, this study aimed to identify critical quality indicators and, if necessary, to develop a continuous improvement plan for harvest of sugarcane billets. For the survey and definition of critical quality indicators the FMEA (Failure Mode and Effect Analysis) was applied, after the formation of the quality technical team. Evaluations of the collected variables were through control charts of individual values and the process capability indexes. There are 8 critical quality indicators in the billets harvesting process; the cutting height, the damage index, the percentage of non-viable buds and operating speed have greater importance for analysis due to the risk priority index and the easiness of obtaining data for analysis. The development of the improvement plan aims to reduce the variability due to crop billets, thus, making it able to perform the operation within the required quality standards.
           (Cucurbita moschata)

    • Abstract: ABSTRACT To maintain seed and soil quality of pumpkin, energy knowledge associated with processing and storage stages is strategic for the optimization of the thermodynamic processes needed for product stabilization. Thus, the objective of this study was to determine isosteric heat, differential entropy, and Gibbs free energy within a temperature range from 20 to 70° C, and relative air humidity levels between 10.75 and 85.11%. The study was based on empirical data for water activity determination. As a result, we verified that as moisture content decreased, the integral isosteric heat of the product increased from 2502.35 to 6231.17 kJ kg-1, differential entropy raised from 1.18 to 12.43 kJ kg-1 K-1, and Gibbs free energy ranged from -243.84 to -432.59 kJ kg-1. Thus, we concluded that the lower the water availability in seeds, the greater the energetic requirement for its removal, as there is a major interaction between water and the product (seeds), indicating an increasingly less spontaneous desorption process.
  • DRYING KINETICS OF BARU FRUITS (Dipteryx alata Vogel)

    • Abstract: ABSTRACT This study aimed to fit different mathematical models to the experimental data on drying of baru fruits (Dipteryx alata Vogel), determine and assess the effective diffusion coefficient, as well as obtain the activation energy and thermodynamic properties for the drying process under different air temperature conditions. Baru fruits with an initial moisture content of 0.429 ± 0.044 (dry basis, db) were dried in a forced air ventilation oven under four temperature conditions (40, 60, 80, and 100 °C) until reaching a moisture content of 0.065 ± 0.018 (decimal db). These data were fitted to mathematical models frequently used to represent the drying of vegetal products. The Logarithmic model presented the best fit to describe the phenomenon. The effective diffusion coefficient increased as temperature increased, being described by the Arrhenius equation, with an activation energy of 37.64 kJ mol-1. Enthalpy and entropy decreased, while Gibbs free energy increased as drying temperature increased.

    • Abstract: ABSTRACT This study aims to quantify the uncertainties associated to the parameters of a Gaussian spatial linear model (GSLM) and the assumption of normality residuals in the modeling of the spatial dependence of the soybean yield as a function of soil chemical attributes. The spatial bootstrap methods were used to determine the point and interval estimators associated with the model parameters. Hypothesis tests were carried out on the significance of the model parameters and the quantile-quantile probability plot was elaborated to verify the data normality. The uncertainties associated to the parameters of the spatial dependence structure were quantified and the potassium content, phosphorus content and soil pH covariates were significant to explain the soybean yield mean. These covariates were used in the elaboration of a new model, which provided the elaboration of a contour map of soybean yield. Analysis of the quantile-quantile plot indicated that soybean yield data follow a normal probability distribution.

    • Abstract: ABSTRACT Many studies have determined the concentration of trace elements in river sediments in Brazil. Notwithstanding, mercury assessments are scarce, especially because of exclusive extraction techniques and expensive analysis techniques. Still, this element is known for its toxicity, persistence, and bioaccumulation, making its presence in the environment an important factor for biota and human health. For this reason, the objective of this study was to determine the mercury concentration in the sediment of the Pelotas River basin, located on the border of the states of Santa Catarina and Rio Grande do Sul. The sediment was collected at eight locations of the Pelotas basin and, after drying, the mercury was quantified by atomic absorption spectrometry based on the Zeeman-background correction, coupled to a pyrolysis reactor. The mercury concentrations in the sediments of the Pelotas River varied from 40.5 ng g-1 to 62.0 ng g-1 and presented a positive correlation with the fraction of silt and clay. The concentrations of mercury found in sediments of the Pelotas River basin have a low probability of negatively affecting the biota. Nonetheless, given the persistence and bioaccumulation potential of this element, the aforementioned region needs further studies to quantify the risks it may cause on the local biota and human health.

    • Abstract: ABSTRACT Aquatic sediments are widely used for the evaluation of anthropogenic contamination due to their ability to adsorb particles and contaminants, making them historical environmental archives. Therefore, the objective was to evaluate the contamination of the Pelotas River sediments, at the border between the states of Santa Catarina and Rio Grande do Sul, by organochlorine and organophosphorus compounds, determining the ecological risk. The evaluation was carried out with quarterly sediment collections in 8 points, totalizing four campaigns within one year, with the aid of the Peterson dredger. Among organochlorines, p'p'DDT stands out regarding environmental persistence, representing 53.23% of the contaminated samples, with values varying up to 0.158 ppb. As for the organophosphates, Methyl Parathion obtained larger representation with 48.4% of the contaminated samples, with concentrations ranging up to 2.42 ppb. The ecological risk of selected organochlorines demonstrated no problems associated with the biota. Regarding the organophosphates studied, Disulfoton presented a risk factor with significant potential for adverse effects on organisms. Therefore, the need for monitoring and sustainability in the use and application of pesticides is well known, aiming at environmental quality and the preservation of natural resources.

    • Abstract: ABSTRACT This study aimed to determine some transport parameters of potassium in soil columns by miscible displacement of effluent from a Sewage Treatment Plant (STP). This effluent was collected at different stages of treatment, and potassium chloride solutions were prepared with the same K pulse concentration as the effluent. They were used to conduct a miscible displacement experiment of potassium in soil columns of dystrophic Red Latosol. Both types of solutions contained concentrations of 30 and 32 mg L-1 of potassium. STANMOD software was used to obtain the retardation factor (R) and the Peclet number (Pe) from pore volume and relative concentration. Both retardation factor and solid-water partition coefficient of the soil showed significant results by ANOVA. When assessing KCl solutions, retardation factor was higher than that observed for the effluent, resulting in higher soil-solute interaction. The presence of other competitor cations in the effluent caused less potassium adsorption by the soil. Based on the results, potassium provided a greater groundwater pollutant potential when applied via effluent than solutions of potassium chloride with the same ion concentrations.

    • Abstract: ABSTRACT The aim of this study was to present and to evaluate methodologies for the estimation of soil resistance to penetration (RP) using artificial intelligence prediction techniques. In order to do so, a data base with values of physical-water characteristics of the soils available in the literature was used, and the performances of Artificial Neural Networks (ANN) and Support Vector Machines (SVM) were evaluated. The models generated from the ANNs were implemented through the multilayer perceptron with backpropagation algorithm of Matlab software, varying the number of neurons in the input and intermediate layers. For the procedure from SVM, the RapidMiner software was used, varying input variables, the kernel function and the coefficients of these functions. The efficiency of the techniques was analyzed by the ratio 1:1, and later, compared to the Busscher non-linear model (Busscher, 1990). The results showed that the artificial intelligence models (ANN and SVM) are efficient and have predictive capacity superior to the Busscher model, under data conditions of soils with textural classes and different, and similar managements, although with higher performance index values for conditions of soils of the same textural class exposed to the same management.

    • Abstract: ABSTRACT Phosphorus losses in runoff water and eroded sediment may increase the risk of eutrophication. Erosion prediction models can be used to assess and quantify nutrient losses and transport in different soil management scenarios. This study aimed to assess the performance of models to estimate the losses of available phosphorus in eroded sediments and assess their spatial variability pattern. The experiment was installed on a eutrophic Red Ultisol located in Tabapuã, northwestern São Paulo State, São Domingos Stream Watershed. Aiming at estimating and validating the models, measurements were made from 2007 to 2015 at 17 observation points (slopes), determining soil phosphorus content (Psoil), eroded sediments (Psed), and enrichment rate (ERsed). The models applied to estimate the enrichment rates of phosphorus in the eroded sediment and runoff are efficient when in use with the predictions of the model Water Erosion Prediction Project (WEPP). The enrichment rates obtained presented a Nash-Sutcliffe (NS) coefficient close to 1. Losses of soluble phosphorus in runoff above 0.02 mg L−1, a critical value for eutrophication, can be obtained in 81% of the watershed area with a probability higher than 75%.

    • Abstract: ABSTRACT Phosphorus losses in runoff water and eroded sediment may increase the risk of eutrophication. Erosion prediction models can be used to assess and quantify nutrient losses and transport in different soil management scenarios. This study aimed to assess the performance of models to estimate the losses of available phosphorus in eroded sediments and assess their spatial variability pattern. The experiment was installed on a eutrophic Red Ultisol located in Tabapuã, northwestern São Paulo State, São Domingos Stream Watershed. Aiming at estimating and validating the models, measurements were made from 2007 to 2015 at 17 observation points (slopes), determining soil phosphorus content (Psoil), eroded sediments (Psed), and enrichment rate (ERsed). The models applied to estimate the enrichment rates of phosphorus in the eroded sediment and runoff are efficient when in use with the predictions of the model Water Erosion Prediction Project (WEPP). The enrichment rates obtained presented a Nash-Sutcliffe (NS) coefficient close to 1. Losses of soluble phosphorus in runoff above 0.02 mg L−1, a critical value for eutrophication, can be obtained in 81% of the watershed area with a probability higher than 75%.
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
Home (Search)
Subjects A-Z
Publishers A-Z
Your IP address:
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-