Palmas de Monte Alto, Brazil
Palmas de Monte Alto, Brazil

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Rodrigues M.O.D.,Federal University of Tocantins | Dos Santos A.C.,Federal University of Tocantins | Junior O.S.,Federal University of Tocantins | Sousa L.F.,Federal University of Tocantins | De Faria A.F.G.,University of Tocantins
Semina:Ciencias Agrarias | Year: 2017

The aim of this study was to investigate the effect of nitrogen (N) concentration during the establishment period of Mombasa grass (Panicum maximum Jacq.). The experiment was conducted using four different N concentrations (0, 30, 60 and 90 kg N/ha) during the establishment period in order to evaluate the effect of nitrogen on the plant. These effects were assessed using different indexes, including the efficiency of nitrogen use and agricultural, physiological and nutritional efficiencies. We also determined the total dry matter and nitrogen accumulation in the plant. The recovery of applied N and the agronomic efficiency of Mombasa grass were found to be greater with increasing N concentrations, and all indexes tested were found to be affected by the concentration of applied N. Based on the indexes studied, 90 kg N/ha was found to be most suitable for Mombasa grass during the establishment period.


Monteiro C.D.C.,IFTO Federal Institute of Education | Gondim P.R.D.L.,University of Brasilia | Rios V.D.M.,University of Tocantins
International Conference on Advanced Communication Technology, ICACT | Year: 2010

Handoff in a distributed IEEE 802.11 Wireless LAN network is a source of significant amount of problems on the video transmission environment. The visual quality of video streaming applications is lowered when stations are in handoff status. In this paper we introduce an architecture of a session proxy (SP), which tries to preserve the quality of the streaming video upon each handoff between access points. We have evaluated thresholds of RSSI and Loss Frame Rate (LFR) for deciding the moment when the handoff process shall begin. Our solution performance was evaluated in a testbed implementation for MPEG-4 video-on-demand with one video server (VLS) and two FreeBSD based access points supporting Mobile IP, DHCP Server and IAPP approach.


De Miranda Rios V.,University of Tocantins | De Lira Gondim P.R.,University of Brasilia | De Castro Monteiro C.,Federal Institute of Education
International Conference on Advanced Communication Technology, ICACT | Year: 2012

Two proposals are presented in this study in an attempt to solve the problem of network selection, which are based on fuzzy logic techniques and methods of decision making. The first proposal uses a combination of the fuzzy method with two MADM (Multiple Attribute Decision Making) methods, the AHP (Analytic Hierarchy Process) and the GRA (Grey Relational Analysis), whereas the latter uses only the fuzzy logic technique. The two are compared with each other and with a third proposal, which uses a combination of AHP method along with a cost function. The results show that the two proposals presented in this paper are more efficient to sort and select the best access network compared to the third one. © 2012 GIRI.


De Miranda Rios V.,University of Tocantins | De Castro Monteiro C.,Fecleral Institute of Education | Cunha V.C.,University of Brasilia
International Conference on Advanced Communication Technology, ICACT | Year: 2014

This article presents two proposals in order to solve the problem of choosing the best access network available in the environment where the user is located. One based on a combination of fuzzy logic technique with two decision-making methods, AHP (Analytic Hierarchy Process) and GRA (Grey Relation Analysis), and the other based only on fuzzy logic technique. In order to demonstrate the effectiveness of these proposals, they were compared with a third one, of the authors in [7], which uses a combination of AHP method with a cost function. The obtained results show that the two proposals presented in this paper are more efficient in sorting and selecting the best access network when compared to the third. © 2014 Global IT Research Institute (GIRI).


Rambo M.K.D.,University of Tocantins | Ferreira M.M.C.,University of Campinas | Amorim E.P.,Embrapa Cassava and Fruits
Chemometrics and Intelligent Laboratory Systems | Year: 2016

The physical-chemical composition of multiple biomasses can be predicted from one single calibration model instead of compositional prediction conducted by individual models. In this work, multi-product models, involving banana, coffee and coconut samples were built by partial least square regression (PLS) for ten different chemical constituents (total lignin, klason lignin, acid insoluble lignin, acid soluble lignin, extractives, moisture, ash, glucose, xylose and total sugars). The developed PLS models show satisfactory results, with relative error (RE%) less than 20.00, except for ash and xylose models; ratio performance deviation (RPD) values above 4.4 and range error ratio (RER) values above 4.00. This means that all models are qualified for screening calibration. Principal component analysis (PCA) was useful to demonstrate the possibility and the rationale for combining three biomass residues into one calibration model. The results have shown the potential of NIR in combination with chemometrics to quantify the chemical composition of feedstocks. © 2016 Elsevier B.V..


Rambo M.K.D.,University of Campinas | Rambo M.K.D.,University of Tocantins | Schmidt F.L.,University of Campinas | Ferreira M.M.C.,University of Campinas
Talanta | Year: 2015

The present study aims to identify the renewable resources available in Brazil such as açai seed, coconut husks, coffee husks, rice husks, eucalyptus sawdust, grass, soy peel, bamboo, banana stems and banana stalks. To identify such renewable energy sources, samples were examined for their physical and chemical characteristics using X-ray diffraction (XRD), proximate and ultimate analyses, thermogravimetric analysis (TGA), calorific value determination, near-infrared (NIR) spectroscopy, UV spectroscopy, high-pH anion-exchange chromatography (HPAEC-PAD) and accelerated solvent extraction (ASE). Among the biomasses, açai and coffee exhibited higher total sugar content, 67.70% and 62.55%, respectively. Sawdust exhibited low ash, along with the highest calorific value and lignin content. The highest glucose contents were observed in bamboo (44.65%) and sawdust (38.80%). The maximum yield for the bioproducts levulinic acid (LA), formic acid (FA) and furfural were estimated; açai exhibited the highest yield of LA and FA, while coffee exhibited the best furfural yield. All of these properties indicate that the residues are potential candidates for bioenergy production. © 2015 Elsevier B.V. All rights reserved.


Rambo M.K.D.,University of Campinas | Rambo M.K.D.,University of Tocantins | Alves A.R.,Sugarcane Research Center | Garcia W.T.,Sugarcane Research Center | Ferreira M.M.C.,University of Campinas
Talanta | Year: 2015

Near infrared (NIR) spectroscopy was used to determine the content of Klason lignin, acid-soluble lignin, total lignin, extractives, ash, acid-insoluble residue, glucose, xylose, rhamnose, galactose, arabinose, mannose and total sugars in coconut residues. The samples were analyzed at several processing stages: wet unground (WU), dried unground (DU) and dried and sieved (DS). Partial least squares models were built, and the models for the analytes exhibited R2>0.80, with the exceptions of rhamnose, arabinose, galactose, mannose and ash from all fractions, and the lignin content from the WU fraction, which were predicted poorly (R2<0.70). There were some significant differences between the models for the main lignocellulosic components at the various stages of biomass. These results proved that NIR spectroscopy is useful for analysis at biorefineries, and it can be used as a faster and more economical alternative to the standard methods. © 2015 Elsevier B.V. All rights reserved.


Malfatti S.M.,University of Tocantins | Yepes I.,University of Tocantins
Proceedings - 2014 16th Symposium on Virtual and Augmented Reality, SVR 2014 | Year: 2014

An exergame can be defined as a software application that combines electronic games and exercises, in which the player uses his body movements to interact with a virtual world. This paper describes the design and application of an exergame called Virtual Bike by which is possible to capture the movements that the player do on a real bycicle using a Kinect sensor. © 2014 IEEE.


PubMed | Sugarcane Research Center, University of Tocantins and University of Campinas
Type: | Journal: Talanta | Year: 2015

Near infrared (NIR) spectroscopy was used to determine the content of Klason lignin, acid-soluble lignin, total lignin, extractives, ash, acid-insoluble residue, glucose, xylose, rhamnose, galactose, arabinose, mannose and total sugars in coconut residues. The samples were analyzed at several processing stages: wet unground (WU), dried unground (DU) and dried and sieved (DS). Partial least squares models were built, and the models for the analytes exhibited R(2)>0.80, with the exceptions of rhamnose, arabinose, galactose, mannose and ash from all fractions, and the lignin content from the WU fraction, which were predicted poorly (R(2)<0.70). There were some significant differences between the models for the main lignocellulosic components at the various stages of biomass. These results proved that NIR spectroscopy is useful for analysis at biorefineries, and it can be used as a faster and more economical alternative to the standard methods.


PubMed | University of Tocantins and University of Campinas
Type: | Journal: Talanta | Year: 2015

The present study aims to identify the renewable resources available in Brazil such as aai seed, coconut husks, coffee husks, rice husks, eucalyptus sawdust, grass, soy peel, bamboo, banana stems and banana stalks. To identify such renewable energy sources, samples were examined for their physical and chemical characteristics using X-ray diffraction (XRD), proximate and ultimate analyses, thermogravimetric analysis (TGA), calorific value determination, near-infrared (NIR) spectroscopy, UV spectroscopy, high-pH anion-exchange chromatography (HPAEC-PAD) and accelerated solvent extraction (ASE). Among the biomasses, aai and coffee exhibited higher total sugar content, 67.70% and 62.55%, respectively. Sawdust exhibited low ash, along with the highest calorific value and lignin content. The highest glucose contents were observed in bamboo (44.65%) and sawdust (38.80%). The maximum yield for the bioproducts levulinic acid (LA), formic acid (FA) and furfural were estimated; aai exhibited the highest yield of LA and FA, while coffee exhibited the best furfural yield. All of these properties indicate that the residues are potential candidates for bioenergy production.

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