bluuebunny/crossref_metadata_2025 huggingface dataset:
Flexible Body Grasping Simulation in ADAMS
Authors: Zhang Yu , Fu Zhong Jun , Liu Hui Fang
Published: January 2014

Analysis of Flexible Body is a difficult problem in system dynamics analysis. In the paper, the basic theory of ADAMS flexible body and some methods of adding flexible bodies to a model are introduced. And build a system simulation model. Through manipulator grasping tomatoes examples verify the effectiveness of ADAMS flexible body grasp simulation, provide stress and elastic deformation data basis for manipulator grasping flexible body.
Simulation and Experiment of Pressure Pipeline Weakness Monitoring Based on Optical Fiber Bragg Grating
Authors: Liu Yue Ming , Xia Zhong Cheng , Gao Xiao Liang
Published: January 2014

Pressure pipelines have been applied widely in the chemical industry, the petroleum enterprises and the electrical power plants. Leakage and explosion accidents happened frequently owing to the weakness of the pressure pipeline. To monitoring the pressure pipeline weakness, a novel method is presented by using optical FBG (FBG: Fiber Bragg Grating) sensors to carry on the real-time monitoring of the pressure piping surface strains. A typical pressure pipeline was fabricated with weak position of L shaped, Tee shaped and U shaped joints. The strains of the weak position were analyzed by the ANSYS software, and then the same weak positions were monitored by experimental method of FBG sensor. The FBG sensor was verified a feasible means to monitoring the pressure pipeline by comparing the ANSYS software results with the experimental results of FBG sensors.
Study on Prediction of Reduction Position Based on Solidification and Heat Transfer Model
Authors: Ren Ting Zhi , Shi Xue Liang , Jin Xin , Han Pei Pei
Published: January 2014

As one of the important parameters of dynamic soft reduction technology, reduction position seriously affects the using effect of this technology to decrease center segregation and porosity of continuous casting slabs. According to the actual production conditions, a two-dimensional solidification and heat transfer model was established. In order to obtain more accurate model, the heat transfer coefficient was amending by the pin shooting technique in measuring shell thickness. The laws of the effect of casting speed, superheat degree and specific water flow on reduction position were analyzed respectively and reduction positions were predicted in different working conditions based on the model. The experimental results show that the center segregation and porosity decreased obviously when it produces at the reduction position predicted by the model.
The Structural Optimization of the 110-Meter Aperture Reflector Antenna in Multi-Levels and Multi-Working Conditions
Authors: Kong Ling Hui , Qiu Yuan Ying , Ma Hong Bo
Published: January 2014

The nonlinear Sequential Quadratic Programming algorithm is adopted to optimize the large reflector antenna with 110-meter aperture. Firstly, an initial finite element model of the antenna is built with the parametric programming language APDL in ANSYS. Then, taking into account of two levels in size and shape and two working conditions in zenith and horizon, the structural optimal model is given with surface precision as the goal. Finally, a better structure satisfying the design requirements is obtained through the structural optimization in multi-levels and multi-working conditions.
Modeling and Development of Copper Wire Annealing Fuzzy Control System Based on Temperature Detecting
Authors: Xu Xue Jun , Lin Yong Zhong , Sun Hong Yang , Lu Yi Gen , Lv Tian
Published: January 2014

Copper wire continuous annealing is a key process of the cable production line. The accuracy of the temperature control directly determines whether the quality of copper wire meets the requirements. In this paper, the fuzzy-PI compound controller was selected and the structure of the annealing temperature fuzzy-PI control system was designed based on temperature measurement. Through the simulation of traditional PI control system and the improved Fuzzy-PI control system, the results show that the Fuzzy-PI controller is better than traditional PI controller. It verifies the feasibility and effectiveness of the Fuzzy -PI controller and proves that Fuzzy-PI algorithm can be successfully applied to the copper wire continuous annealing temperature control system.
The Analysis of Monitoring System of Wind Turbine
Authors: Cao Yan Hua , Cao Yang , Wu Guo Qing , Li Qiao Mei , Shi Yu Juan
Published: January 2014

Monitoring system of wind turbine is the guarantee of normal operation of the wind turbine. It has significance on the study, promotion and application of wind turbines. The research status of wind turbine monitoring system was mainly elaborated. The structure of wind turbine monitoring system was analyzed. The monitoring systems based on VB, VC, configuration software and LabVIEW have been made a comparison. And several further research directions of the wind turbine monitoring system have been proposed.
Design and MATLAB Simulation of a Composite PID Controller for EPS Test-Benches
Authors: Mai Yun Fei , Liu Shao Long , Ding Wen Jing
Published: January 2014

For the problems that exist in EPS composite test-benches, PID control laws are expounded, a composite PID controller is designed, which is integrated with multiple advanced PID control algorithms (variable-integral PID algorithm, PID algorithm with filters, partial derivative PID algorithm, PID algorithm with dead zone), and it is simulated by MATLAB. The simulation results show that the improvement of accuracy and the impacts mitigation of the nonlinearity and external electromagnetic interferences are achieved well through the composite PID controller, and there is practical significance.
Solar Underwater Glider Robot of Viscous Hydrodynamic Numerical Calculation
Authors: Zhang Yu , Wang Lei , Liu Hui Fang
Published: January 2014

Hydrodynamic coefficients of solar underwater glider robot are one of the important indicators to measure its maneuverability. Based on solar underwater glider robot, using ANSYS CFX software simulate analysis, and through the MATLAB data fitting to body hydrodynamic coefficients. Drawing hydrodynamic coefficient curves for the robot is the critical study of underwater robot hydrodynamics, its shape optimization for subsequent theoretical data is important.
Research Methods of Determining the Dot Transfer Function of Multicolor Printer
Authors: He Song Hua , Zhang Gang , Chen Qiao , Zhao Zi Qi , Duan Jiang
Published: January 2014

Y_N model-based printer forward characterization, considering the influence of the physical dot gain and optical dot gain, it needs to determine the effective ink dot percentages and the factor n of Yule-Nielson model through single-channel ink limit and nonlinear optimal method. Based on the foregoing, we can determinate the dot transfer function of multicolor printer. Before Y_N model formula factor n and effective dot percentage being determined, it needs to get the sample by printing each primary color inks foot ladder. However, transferring ink to the substrate occurs obvious physical dot gain issues, while the paper absorbing ink ability is limited, so firstly implementing single channel ink quantity control for printer becomes particularly important. Considering the problem of the optical dot gain resulting model accuracy misfit, Y_N model introduces a parameter factor n to correction.
Adhesion of Streptococcus mutans on Different Types of Orthodontic Elastic O-Rings
Authors: Aung Yadana , Luppanapornlarp Suwannee , Thaweboon Sroisiri , Boonpratham Supatchai , Dechkunakorn Surachai , Thaweboon Boonyanit
Published: January 2014

Objective: The aim of this study was to evaluate the adhesion ofStreptococcus mutans (S. mutans)on different types of orthodontic elastic O-rings.
Investigation of Microstructural Changes after Solution Annealing Treatment in a Duplex Stainless Steel
Authors: Cronemberger Maria E.R. , de Mendonça Renato , Maestrelli Sylma Carvalho , Campos Maria Gabriela Nogueira , Ramos Erika C. Trindade , Mariano Neide A.
Published: January 2014

This work investigates the microstructural changes developed during the solution annealing treatment under different conditions for the steel UNS S31803. The studied material was submitted to solution anneal at 1100°C for 30, 120 and 240 min, followed by cooling in water, air and furnace. The results evaluation was based on micrographic analysis and the results showed the influence of treatment period and cooling rates in distribution and morphology of austenitic phase. It was observed the same morphology of austenitic phase in all treatment conditions, however, the volume fraction of this phase increased with the treatment period increase, and further refinement with lower cooling rates. It was found that the solution treatment by longer period with the lower cooling rate significantly enhanced the intermetallic phases transformation. The intermetallic phases precipitation could be detected when the samples were solution-treated for 120 and 240 min and cooled at furnace.
Microstructural Characterization of CP Steel Used in Automotive Industry
Authors: Dias Erica , Horimoto Laís , dos Santos Pereira Marcelo
Published: January 2014

This study aims to characterize the microstructure of the complex phase steel (CP). Using the conventional and colored metallographic analysis with 3% Nital etchant, sodium metabisulfite 10% and LePera. Techniques were applied in this work of optical microscopy, using, besides the lighting in bright field, dark field illumination of the reverse contrast in bright field illumination, the method of polarized light, which generates colorful contrast, providing a complementary identification phases present in the microstructure, and the system by differential interference contrast (DIC). The results obtained by metallography CP indicates that the steel has a microstructure composed of ferrite, retained austenite, bainite and martensite and precipitates arranged in a refined and complex morphology. Besides bright field illumination others optical microscopys techniques such as dark field illumination were applied.
Electrodeposition of Polypyrrole Films on 2024 Aluminum Alloy in Phosphoric Acid Solution
Authors: Liu A.S. , Xavier Thiago Henrique Andrade , Cintra E.P , Cho L.Y.
Published: January 2014

Polypyrrole was synthesized onto aluminum surfaces by electrochemical polymerization technique using pyrrole monomer and phosphoric acid in aqueous medium. The influence of applied potential on the morphology of the films was studied by Scanning electron microscopy (SEM). The films displayed a cauliflower-like structure consisting of micro-spherical grains. This structure is related to dopant intercalation in the polymeric chain. The efficiency of these polymeric films to protecting aluminum alloy against corrosion was investigated by potentiodynamic polarization curves. It was also observed that the polymer roughness depend on the applied potential.
Infra-Red Spectroscopy Analysis of Malva Fibers
Authors: Monteiro Sergio Neves , Margem Frederico Muylaert , Margem Jean Igor , de Souza Martins Lucas Barbosa , Oliveira Caroline Gonçalves , Oliveira Michel Picanço
Published: January 2014

The growing interest for natural materials as an environmentally friendly alternative for the substitution of energy intensive and non-sustainable synthetic materials, has motivated the use of lignocellulosic fibers as reinforcement of polymer composites. The malva fiber, a relatively unknown lignocellulosic fiber with potential for composite reinforcement, still needs to be characterized for possible engineer applications. Therefore, the present work analyzed the malva fiber by means of Fourier Transform Infra-red (FTIR) spectroscopy. The malva fiber FTIR spectrum revealed main absorption bands typical of any lignocellulosic fiber. However, some specific bands as well as bands broadening and intensity suggested particular activities for functional molecular groups in the malva fiber.
Charpy Impact Tests in Epoxy Matrix Composites Reinforced with Continuous Sisal Fiber
Authors: Monteiro Sergio Neves , Margem Frederico Muylaert , Camposo Pereira Artur , Simonassi Noan , Oliveira Michel Picanço
Published: January 2014

The objective of this work was to investigate the toughness behavior of epoxy matrix composites reinforced with up to 30% in volume of long, continuous and aligned sisal fibers by means of Charpy impact tests. The addition of sisal fibers results in a visible improvement in the energy absorption ability of the composites. Macroscopic observation of the post-impacted specimens and the SEM fracture analysis showed that longitudinal rupture through the sisal fiber interface with the epoxy matrix is the main mechanism for the higher toughness attended by these composites.
Alternative Coconut Fiber Surface Treatments Methods for the Development of Polymeric Matrix Composites
Authors: Yamane Fabíola Ottoboni , da Silva Mara Lucy Aparecida , França Dener Israel , Mantuvanelli Murilo Vichietti , Thomazini Daniel , Gelfuso Maria Virgínia
Published: January 2014

The coconut fibers are an abundant source of natural materials, renewable, high-availability, accessibility and biodegradable. This great interest in developing and using materials made from renewable sources occurred mainly in response to the global attention for the use of natural products and the preservation of the environment. In this paper, coconut fibers received different surface treatments, environmentally friendly, based on high values of temperature and pressure. The coconut fibers were characterized by FTIR, SEM, water absorption, weight loss and wetting angle. The results indicated that the methods were effective, changing the chemical composition of the fiber as well as their surface morphology and raising the hydrophobic character. Thus, the compatibility between the fiber and the polymeric matrix should be increased, providing the application of these new fibers in the development of composite materials.
Influence of Speed of Processing in the Mechanical and Thermomechanical Properties of Polyamide 6 / Organoclay Nanocomposite
Authors: da Paz Renê Anísio , Araújo E.M. , Pessan L.A. , Melo T.J.A. , Leite A.M.D. , Passador F.R.
Published: January 2014

The improvement in the properties of nanocomposites is achieved with a load volume fraction of up to 10% due to the very high ratio of the load aspect. Moreover, they have the advantage of being processed with conventional equipment and techniques (extrusion, injection, etc.) used for polymers. In order for the clay to be uniformly dispersed in the polymer and there to be good interaction with the polymer matrix, superficial treatments of the clays with organic salts are essential for it to become organophilic, and, thus the material obtained has better performance. In this study, it was evaluated the influence of two speeds (100 and 200 rpm) of processing and thermo mechanical properties of nanocomposites with 3% of bentonite clay prepared with two speeds and two threads. The nanocomposites showed better properties as compared to properties of polyamide 6, especially the samples heated at screw speed of 100 rpm.
Influence of TiO2 Crystalline Structure on Dielectric Resonator Properties from ZnO-Nb2O5-TiO2 Ceramic System for Use in Telecommunications
Authors: Nono Maria do Carmo Andrade , Castro Pedro José , Rangel Elizete G.L. , Mineiro Sergio Luiz
Published: January 2014

This paper presents an investigation of the correlation between dielectric properties and microstructure and TiO2 crystalline-phase characteristics (rutile and anatase) in ZnO-TiO2-Nb2O5 system ceramics. Such ceramics were produced from powder mixtures of zinc oxide, niobium oxide and titanium oxide. Powder mixtures were compressed by pressing (100 MPa uniaxial and 300 MPa isostatic) and sintered at 1100, 1200 and 1250 °C. The sintered ceramics were characterized on the crystalline phases, density and microstructure and microwave frequencies. As for the microwave dielectric properties, dielectric constant, quality factor and thermal coefficient in the temperature range from-20 to 50 °C were measured. The results showed that the type of titanium oxide structure (rutile or anatase) causes influence on the type and quantity of crystalline phases in relative density of sintered ceramics and, consequently in their dielectric properties measurements.
Effect of Oxygen Content during Sintering on the Losses of MnZn Ferrites
Authors: Real Janasi Susilene , Lázaro-Colán Victoria A. , Landgraf Fernando J.G. , de Campos Marcos Flavio
Published: January 2014

The magnetic properties of MnZn ferrites are highly influenced by the partial oxygen pressure during sintering. In this work MnZn ferrites with different chemical compositions were pressed in a toroidal form and sintered at 1290 °C for 6 h at different oxygen pressures. X ray diffraction using K-edge radiation of Fe, Zn and Mn were performed in order to identify the atomic preference in the MnZn ferrite spinel structure, by means of Rietveld analysis. Magnetic losses were measured at 25 °C and 100 °C (200mT, 100 kHz). The high temperature loss decreased with the increase of oxygen content during sintering whereas at room temperature this effect was opposite. The losses behavior as function of frequency was analyzed according the loss separation model.
Characterization and Study of the Moisture Expansion of Ceramic Blocks from Ceramic Masses Incorporated with Kaolin and Granite Wastes
Authors: Mendonça Ana M.G.D. , Chaves Alexsandra Cristina , Neves Gelmires Araújo , de Lima Santana Lisiane Navarro
Published: January 2014

The study of moisture expansion (ME) in ceramic products has been object of research in the past few years, especially in UFCG. The ME is the increase of the dimensions of the ceramic materials by adsorption of water, it occurs slowly and is relatively small, being able to compromise the adherence of the ceramic plates to the subfloor, lead to the cracking of the glaze and conduct to the appearance of cracks in bricks, if the tensions generated by the deformation contained in the pieces exceed the limit resistance of the materials. Aiming to contribute with this research, this study aimed to characterize the alternative ceramic masses from ceramic blocks, seeking to determinate their influence in the development of the moisture expansion phenomenon. Compositions were formulated through the design of simplexes network mixtures technique. The specimens were conformed by uniaxial pressing at 20 MPa, dried in an oven at 110 °C and fired at temperatures of 800°, 900° and 1000 °C. After firing the MEs were determined by boiling and immersion. The results showed that the higher the percentage of granite waste in the formulation, lower the ME.
Study of Temperature Sintering by Microwave Energy in Ferrites Ni0,5Zn0,5Fe2O4
Authors: Diniz Verônica Cristina Souza , Vieira Débora A. , Kiminami Ruth Herta Goldsmith Aliaga , Cornejo Daniel , de Melo Costa Ana Cristina Figueiredo
Published: January 2014

This study proposes to evaluate the influence of the variation of sintering temperature on microstructural characteristics and magnetic ferrite Ni0,5Zn0,5Fe2O4sintered by microwave energy. The samples were sintered at 900, 1000, 1100 and 1200°C for exposure time of 10 minutes, with rate 50°C/minutes and characterized by density and porosity, X-ray diffraction, scanning electron microscopy and magnetic measurements. The results indicate that the values of density and apparent porosity were 4.2, 4.5, 4.4 and 4.5 g/cm3and 3.4, 2.1, 2.2 and 2.4% for the sintering temperatures of 900, 1000, 1100 and 1200°C respectively. The formation of the ferrite phase Ni0,5Zn0,5Fe2O4been identified for all conditions of sintering, with grain sizes of 52, 62, 71 and 58nm and saturation magnetization values of 63, 68, 69 and 27 emu/g to temperatures sintering 900, 1000, 1100 and 1200°C respectively.
Thermal Activation of Palygorskite at Different Temperatures
Authors: Cruz Magalhães Xavier Katiane , do Socorro Ferreira Santos Maria , Santos Maria Rita de Morais Chaves , Benvindo Luz Adão , Leite Brasileiro Luzana , Nunes Cordeiro Carvalho Maria Wilma , Silva Filho Edson Cavalcanti
Published: January 2014

The palygorskite or attapulgite is a mineral clay that has a fibrous morphology with porous crystalline structure, hydrated of type 2:1, which is constituted by layer-shaped strips with two tetrahedral layers connected by a central octahedral layer through the sharing of common oxygens [. It presents in its structure low surface charge, high magnesium content and high specific surface area. This mineral clay together with the sepiolite belong to the class of fibrous clay minerals [.
Synthesis and Characterization of Biocompatible Fe3O4 for Use in Cell Hyperthermia
Authors: Sampaio da Silva Fernanda A. , Rojas Edwin E. G. , Rodrigues Girley F. , da Silva Bruno F.A. , de Campos Marcos Flavio
Published: January 2014

Malignant tumors are caused by uncontrolled multiplication of cells in the body. It is possible to stop the growth of atypical cells by overheating (hyperthermia). By the magnetization process of magnetite nanoparticles, energy is dissipated as heat (Joule effect), producing increase of temperature. This causes the rupture of cancer cells. In this work, magnetic nanoparticles were synthesized by coprecipitation method and coated by biocompatible material (chitosan or castor oil). The samples showed required characteristics of nanocrystallinity, superparamagnetism and biocompatibility. This was deduced from hysteresis curve, thermal analysis and X-ray Diffraction data. Thus, the nanocomposite exhibits excellent features for use in vivo.
Microstructural Evolution of a F138 Austenitic Stainless Steel after Deformation by ECAP and HPT
Authors: Kliauga Andrea Madeira , Sordi Vitor Luiz , Dobatkin Sergey V.
Published: January 2014

A F138 austenitic stainless steel was solution heat treated, deformed by equal-channel angular pressing (ECAP) at 25, 100, 200, and 300°C. The equivalent strain was ~0.7 per pass and the applied equivalent strain varied from 0.7 to 4.2. The same material was also deformed by high pressure torsion (HPT) at 300 and 480°C, applying 6GPa pressure and 5 turns; the equivalent strain was ~ 4.5 at r/2 and ~5.2 at the vicinity of the disk edge. Microstructure evolution was observed by transmission electron microscopy (TEM) electron back-scattered diffraction (EBSD) and X ray diffraction. The effect of severe plastic deformation was studied at 25 and 300°C: at 25°C further deformation led to the formation of grain subdivision inside deformation bands and the onset of new grains formation after 2 ECAE passes. The deformation at 300 and 400°C up to 6 passes lead to the formation of recrystallized grains of the order of 100 nm size.
Employment of Response Surface Methodology for Optimization of the Portland Cement Mechanical Resistance
Authors: Oliveira Danielle Nascimento Silva , Neves Gelmires Araújo , Bezerra Ulisses Targino , Chaves Alexsandra C. , Lira B. Silveira
Published: January 2014

For this workmixtureswere madewith three types ofPortland cement (CPII,CPIII, and CPIV), which were chosen because theyexhibit: good mechanical properties,lower heat ofhydrationgeneratedin the reaction, greater impermeability, greater resistance to environmentsaggressive.The objectwas to improve themechanical strengthofcementpasteswith the helpof experimental design. Ten different compositionswere prepared, which were tested forcompressivestrengthat 1 and14 days ofcuring. The results illustrated that the first day; the composition showed that the best result was composed of 50% of CP II and 50% of CP III. Already at 14 days, a paste made with 100% of CP III showed better results followed by composition made with 50%CP II and CP III 50%.
Study on Physical and Mechanical Properties of PHB Biocomposites with Rice Hull Ash
Authors: Alberti Leila Denise , Souza Osvaldo Francisco , Bucci Doris Zwicker , Barcellos Ivonete Oliveira
Published: January 2014

The development of biodegradable polymer composites is a promising alternative for obtaining environmentally friendly materials. The aim of this study was to develop polyhidroxybutyrate (PHB) composites with rice husk ashes and evaluate mechanical properties by tensile tests, determining stress and elongation at break and modulus of elasticity, flexural strength test and Izod impact tests, as well as density and hardness. The composites showed impact strength up to 25% greater than the polymeric material containing only PHB. Also for the testing of tensile strength in bending showed significant improvements in the composites up to 15%. The results indicate that the ash as filler in PHB is viable for applications in materials that already use the PHB in pure form, considering the technical aspects studied (processing and properties) and the environment, since in most tests there was a gain or maintenance of properties when compared to PHB.
Alumina Matrix Composites Produced by Water-Based Tape Casting
Authors: Amadio Tatiane Mattos , Neto João B. Rodrigues , Hotza Dachamir
Published: January 2014

This work aimed to develop an alumina composite reinforced with polycrystalline alumina fibers to increase the mechanical properties of the product. A water-based processing was carried out, replacing the use of toxic and flammable organic solvents. The forming technique used was tape casting, which in addition to reliability and low cost, enables to make thin, flat tapes. The parameters for the tape casting process were: gap between the blades of 350 μm and casting speed of 12 cm/min. The process was optimized through a rheological study and alumina suspension with 50 wt.% solids was used. The slurry showed a pseudoplastic behavior and a high value of thixotropy. Several methods for separation and processing of the fibers were tested and a scattering using a specially designed support was the most efficient option. The tapes were thermopressed at 65°C and 30 MPa. The tensile test of green tapes showed a significant increase of the mechanical resistance for fiber-reinforced tapes, which was also dependent on fiber orientation.
Application of Clays in Composition of Asphaltic Masses
Authors: Ramalho Pinto Eric , Ravanelli Costa Jéssica , Teixeira Dias Michele , de Amorim Pedro Lopes Lucas , Mariano Neide Aparecida , Maestrelli Sylma Carvalho
Published: January 2014

The inclusion of alternative materials in the composition of asphaltic masses aims to solve the problems arising from the disposal, in the environment, of industrial waste discarded; however, to ensure that such inclusion doesn't damage the characteristics and properties of the asphaltic mass, it is necessary that the mixtures, composed by mineral aggregates, PAC and filler, are previously submitted to the standardized essay. It is known that the filler is mainly responsible for the absorption of the PAC and that, the greater the amount of the PAC utilized on the asphaltic mass, the bigger the costs. Thus the characteristics of the filler, as well the rate of packing of the constituents of the asphaltic mass affects directly the cost and properties of the final product. Given the previous subject, in this work it was aimed to study the effect of the addition of low plasticity clay and peat in the final properties of the asphaltic masses.
Evaluation of the Physico-Mechanical Properties of Concretes Containing Pet and Crushed Sand
Authors: Aquino José Lourenço Santos , Morais C.R.S.
Published: January 2014

The practice of sustainability in construction occupies an increasing prominent position in order to preserve the environment. Considering the environmental impacts caused by waste generation, the use of PET bottle flaks and crushed sand in partial substitution of conventional sand used in concretes is proposed. The aim of this work was to formulate concrete compositions with 1:3 and 1:4 mixtures containing varied water/cement factors and 5, 10, 15 and 20% content of PET wastes and gravel powder. The raw materials were characterized by physico-chemical tests. The formulations were subjected to slump tests and the hardened concrete to absorption, void index and simple compressive strength, with curing of 7 and 28 days, tests. The granulometric analysis allowed the calculation of the fineness modulus, which was 1.50, 3.25 and 0.64 for the crushed sand, gravel and PET respectively. The decrease in the strength with the increase in the PET content in the composite was observed, though, in some mixtures the values indicate the possibility of using this concrete in structural elements.
Study of Mechanical Behavior of Components of Duplex Steel by Using of X-Ray Diffraction Technique
Authors: Monin V.I. , Lopes R.T. , Turibus Sergio Nolêto , Blas J.C.G. , Assis J.T.
Published: January 2014

Duplex stainless steel is a material that attracts great interest of different branches of engineering and industry because of its combination of good structural and mechanical characteristics and high corrosion resistance. The microstructure of duplex steel presents an example of composite material with approximately equal amounts of austenite and ferrite phases. Physical and mechanical properties of these components are different so their behaviors under loading are different too. Therefore it is important to analyze the distribution of applied stress between ferrite and austenite phases of duplex steel. The analysis of stress distribution was made by X-ray diffraction technique. X-ray diffraction method allows separate measuring of stresses in each phase and determination of others mechanical characteristics as Young ́s modulus, yield stress of ferrite and austenite both in elastic and plastic region. In presented paper the samples of duplex steel after rolling were loaded by calibrated springs; using of Cr-Kα radiation allows carrying out of stress measurements in ferrite and austenite phases of duplex stainless steel.
Characterization of a Water Clearing Treatment Residue and Its Application as Clay Ceramic Addition
Authors: de Oliveira Carolina Nascimento , Babisk Michelle Pereira , Vernilli Fernando , Candido Veronica Scarpini , Monteiro Sergio Neves , Vieira Carlos Mauricio Fontes
Published: January 2014

The addition of industrial residues into common red clay ceramic has been, from many decades, an alternative of using other low cost raw materials and, more recently, as an environmentally correct destination for polluting substances. An important residue, known as yellow sludge, is that generated at the water clearing stage (WCS) of a treatment plant by some heavy industries such as an integrated steel making. Since this yellow sludge residue is normally disposed in ways that pollutes water bodies, the objective of the present work was to characterize a WCS yellow sludge and investigate its addition into clay ceramics. The residue was characterized by X-ray fluorescence, particle size distribution and scanning electron microscopy. The addition was carried out up to 7.5 wt% followed by firing at 800oC. The added ceramics were evaluated in terms of water absorption, linear shrinkage, dry apparent density and flexural rupture strength. It was found that the residue addition does not practically alter the ceramic technical properties.
Evaluation of Structural and Morphological Characteristics of the System Ni1-xZnxFe2O4 Obtained by Combustion Reaction
Authors: Braga Aluska do Nascimento Simões , Gomes Filho Alberto Correia , Neiva Laédna Souto , Silva Tamiris Rodrigues , Oliveira João Bosco Lucena , Gama Lucianna
Published: January 2014

The synthesis by combustion reaction stands as an alternative technique for preparing powders with high purity level, nanometric particle size and low cost. Therefore, this study had as objective the synthesis and characterization of ferrite powders with nominal composition NI1-xZnxFe2O4(x = 0.6, 0.7 and 0.8 mol) prepared by combustion reaction using urea as fuel. The influence of the quantity of zinc in the final characteristics of the powders was also investigated. The powders were characterized by X-ray diffraction (XRD), nitrogen adsorption (BET) and scanning electron microscopy (SEM). All compositions resulted in nanometric powders of Ni-Zn ferrites with direct formation of the inverse spinel phase, showing the effectiveness of the synthesis method applied. The increase of zinc's concentration caused an increase in surface area, ranging 4 m2g-1from 23 m2g-1. And the SEM micrographs show that the powders have thinner particle morphology with increasing zinc content.
Study of Nanoferrites Ni0,5Zn0,5Fe2O4 and Ni0,1Cu0,4Zn0,5Fe2O4 as Catalysts in the Methyl Transesterification of Soybean Oil
Authors: Dantas Joelda , Santos J.R.D. , Silva F.N. , Silva A.S. , Costa A.C.F.M.
Published: January 2014

Research with emphasis on substitution of energy sources used in worldwide for renewable energy undoubtedly indicates that the use of biodiesel would be an option to increase the income in rural areas, reduction in oil derivatives spending and also new opportunities for job creation. Soon, in purpose to contribute with the research growth, this research proposes to evaluate the new catalysts performance as nanoferrites Ni0,5Zn0,5Fe2O4 (pure) and Ni0,1Cu0,4Zn0,5Fe2O4 (doped with 0.4 mol of Cu2+) in transesterification reactions of soybean oil methyl. For both samples were synthesized by chemical method in the stoichiometry of the combustion reaction, using urea as a fuel source and a resistance heating coil. During synthesis were measured time and combustion temperature. Later they were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), textural analysis (BET) and subjected to catalytic tests bench. The reaction conditions used in the transesterification were: 10 g of oil, 2 h reaction time, molar ratio of 1:20 oil and alcohol, 4% (w/w) of catalyst and reaction temperature of 160°C. Finally, the reaction product was characterized for conversion into methyl esters by gas chromatography. Results has shown only the presence of the inverse spinel phase, characteristic of Ni-Zn ferrite for both samples, with crystallite size of 26 and 29 nm, respectively. The thermogravimetric analysis has shown that samples are thermally stable, with a weight loss of 4.9 and 3.7%, respectively. The surface area and particle size were 48.89 m2g-1 and 23 nm, and 18.06 m2g-1 and 62 nm, respectively. The conversion results obtained by the transesterification reaction were 13 and 50% Ni0,5Zn0,5Fe2O4 and Ni0,1Cu0,4Zn0,5Fe2O4, respectively, indicating that sample with presence of copper was 26% more effectively, thus being one promising catalyst for the transesterification reaction, which aims to obtain biodiesel.
Artificial Neural Network Assisted Digital Image Processing to Determine the Hydrophobicity of Polymeric Materials
Authors: Thomazini Daniel , de Resende Raphael Ulisses Costa De Resende , Gueratto Daniel Henrique , Gelfuso Maria Virginia
Published: January 2014

Hydrophobicity of polymeric insulators of high power transmission line is an important property because it is a good monitor of aging of polymeric outdoor insulator. An employee on the high-voltage transmission line makes this procedure during operation, which can lead to injuries and incorrect estimation of the insulator integrity. In this way, digital image processing is a promising and objective tool to analyze the polymer surface. In this study, two thousand pictures were taken from the wetted insulator surface and analyzed by artificial neural network assisted digital image processing. The neural network used is based on back-propagation method, and Haralicks descriptors were used to quantify the hydrophobic aspect of various polymeric aged surfaces.
Preparation and Characterization of A Composite Obtained through Ti (IV) and Phosphoric Acid
Authors: Cumba Loanda Raquel , Bicalho U.O. , Carmo D.R.
Published: January 2014

This paper describes the preparation and complementary characterization of a composite formed from the activation of titanium isopropoxide by phosphoric acid and deionized water (TiP).Techniques such as, X-ray diffraction (XRD), Raman , electronic (UV-vis) and Scanning electron microscopies (SEM) were used for characterization of this new composite formed. In the X-ray diffractogram of TIP was observed four intense peaks. A strong absorption was observed in the region 362-445 nm. The scanning electron microscopy of TiP, shows that the prepared material consists mostly of a cluster of spherical particles with diameters ranging from 2.35 to 2.60 μm.
Use of ultrasound to discern differences in Asian noodles prepared across wheat classes and between varieties
Authors: Diep Sally , Daugelaite Daiva , Strybulevych Anatoliy , Scanlon Martin , Page John , Hatcher Dave
Published: January 2014

Diep, S., Daugelaite, D., Strybulevych, A., Scanlon, M., Page, J. and Hatcher, D. 2014. Use of ultrasound to discern differences in Asian noodles prepared across wheat classes and between varieties. Can. J. Plant Sci. 94: 525–534. Nine wheat varieties, five Canada Western Red Spring (CWRS) and four Canada Prairie Spring Red (CPSR), grown at the same locations and composited by variety, were milled to yield 65% extraction flours, which were used to form yellow alkaline raw and cooked noodles. The CWRS flours were ∼2% higher in protein content than the CPSR varieties, with varieties within each class exhibiting a wide range in dough strength as determined by Farinograph dough development time and stability. The ultrasonic velocity and attenuation of the raw noodles were measured at 40 kHz in disk-shaped samples, enabling the longitudinal storage modulus, loss modulus and tan Δ to be determined. Significant differences (P=0.05) between classes and within a class were found to exist for all ultrasonic parameters. In general, the CPSR varieties generated the highest storage moduli values, the lowest loss moduli, and the lowest tan Δ values, indicating this class/varieties exhibited a more elastic (firmer) raw noodle than the CWRS varieties even at a 2% lower protein content. A significant correlation, r=0.72,0.70, P=0.03, was also found between raw noodle velocity and M”, respectively, with cooked noodle bite as determined by maximum cutting stress.
The Influence of Shared Mental Models Between the Cio and the Top Management Team on the Strategic Alignment of Information Systems: a Comparison Between Brazilian and us Companies
Authors: Reinhard Nicolau , Bigueti José Ricardo
Published: January 2014

The gap in the understanding between the chief information officer (CIO) and the management team (TMT) has been cited as a contributing factor to their often troubled relationship. The objective of this study is to examine the development of shared mental models (SMMs) between the CIO and TMT about the role of information systems in the organization. An SMM is conceptualized as a multidimensional construct spanning the dimensions of shared language and shared understanding. The study posits that knowledge exchange mechanisms and relational similarity between the CIO and TMT are key antecedents to the development of SMMs. SMMs between the CIO and TMT are expected to guide the strategic orientation of the organization and may influence strategic alignment and organizational outcomes. The model was tested via a field survey of CIO – TMT pairs using structural equation modeling. Results show that relational similarity and formal mechanisms of knowledge exchange (e.g., formal CIO membership in the TMT, CIO hierarchical level, and formal educational mechanisms by the CIO) are important to the development of SMMs. Contrary to expectations, informal social mechanisms of knowledge exchange and physical proximity were not significantly related to SMMs.
Cash Management Policies by Evolutionary Models: a Comparison Using the Miller-Orr Model
Authors: Moraes Marcelo Botelho da Costa , Nagano Marcelo Seido
Published: January 2014

This work aims to apply genetic algorithms (GA) and particle swarm optimization (PSO) to managing cash balance, comparing performance results between computational models and the Miller-Orr model. Thus, the paper proposes the application of computational evolutionary models to minimize the total cost of cash balance maintenance, obtaining the parameters for a cash management policy, using assumptions presented in the literature, considering the cost of maintenance and opportunity for cost of cash. For such, we developed computational experiments from cash flows simulated to implement the algorithms. For a control purpose, an algorithm has been developed that uses the Miller-Orr model defining the lower bound parameter, which is not obtained by the original model. The results indicate that evolutionary algorithms present better results than the Miller-Orr model, with prevalence for PSO algorithm in results.
Information Technology Management System: an Analysis on Computational Model Failures for Fleet Management
Authors: Oliveira Jayr Figueiredo de , Fernandes Marcelo Eloy , Lima Carlos Roberto Camello
Published: January 2014

This article proposes an information technology model to evaluate fleet management failure. Qualitative research done by a case study within an Interstate Transport company in a São Paulo State proposed to establish a relationship between computer tools and valid trustworthy information needs, and within an acceptable timeframe, for decision making, reliability, availability and system management. Additionally, the study aimed to provide relevant and precise information, in order to minimize and mitigate failure actions that may occur, compromising all operational organization base functioning.
IT Management Model for Financial Report Issuance and Regulatory and Legal Compliance
Authors: Moreira José Rogério Poggio , Da Silva Paulo Caetano
Published: January 2014

The development of information systems for financial report issuance must be adherent to the demands of the law and regulations that regulate the financial market. In order to perform this task, organizations need to implement control in the Information Technology (IT) area to maintain their systems´ conformity to laws and regulations. In the development of this work, it was found, through a state-of-art study, that there are no proposals contemplating the solution of this problem in its totality. In order to achieve this goal, in this paper it is presented a model for Information Technology management constituted by COBIT, ITIL and BPM management good practices, together with SOA and XBRL Technologies. This model is composed by 03 layers that aim at structuring the organization IT and business processes, besides defining a process for implementing SOA and integrating its Web services with XBRL language. One can expect this work to contribute to companies to decrease the negative impact coming from the lack of conformity with laws and regulations, through the creation of a corporative and IT environment that is flexible and more adaptable to changes, which may occur in legal demands, as well as improving the quality and reliability of financial report issuance.
Precipitation dominates fire occurrence in Greece (1900–2010): its dual role in fuel build-up and dryness
Authors: Xystrakis F. , Kallimanis A. S. , Dimopoulos P. , Halley J. M. , Koutsias N.
Published: January 2014

Abstract. Historical fire records and meteorological observations spanning over one century (1894–2010) were assembled in a database to collect long-term fire and weather data in Greece. Positive/negative events of fire occurrence on an annual basis were considered as the years where the annual values of the examined parameters were above (positive values) or below (negative values) the 95% confidence limits around the trend line of the corresponding parameter. To analyse the association of positive/negative events of fire occurrence with meteorological extremes, we proceeded with a cross-tabulation analysis based on a Monte Carlo randomization. Positive/negative values of total annual precipitation were randomly associated with the corresponding values of burned areas, and significant associations were observed for seasonal precipitation totals (spring and fire season). Fire season precipitation is the dominant factor coinciding with negative values of area burned, while years with high spring precipitation coincide with years with large areas burned. These results demonstrate the dual role of precipitation in controlling a fire's extent through fuel build-up and dryness. Additionally, there is a clear outperformance of precipitation-related variables compared with temperature-related weather revealing that, at least in Greece, total area burned at the national scale is controlled by precipitation totals rather than air temperature. This analysis improves our understanding of the underlying mechanisms of fire regimes and provides valuable information concerning the development of models relating fire activity to weather parameters, which are essential when facing a changing climate that may be associated with shifts in various aspects of the typical fire regimes of ecosystems. Our results may allow fire managers to more easily incorporate the effect of extreme weather conditions into long-term planning strategies. They contribute to the exploration of fire–climate relationships and may become more important if climate change scenarios are used to predict the occurrence of future extreme weather taking into consideration that climate change is discussed on the basis of changes of extremes rather than changes in means.
Power law statistics of force and acoustic emission from a slowly penetrated granular bed
Authors: Matsuyama K. , Katsuragi H.
Published: January 2014

Abstract. Penetration-resistant force and acoustic emission (AE) from a plunged granular bed are experimentally investigated through their power law distribution forms. An AE sensor is buried in a glass bead bed. Then, the bed is slowly penetrated by a solid sphere. During the penetration, the resistant force exerted on the sphere and the AE signal are measured. The resistant force shows power law relation to the penetration depth. The power law exponent is independent of the penetration speed, while it seems to depend on the container's size. For the AE signal, we find that the size distribution of AE events obeys power laws. The power law exponent depends on grain size. Using the energy scaling, the experimentally observed power law exponents are discussed and compared to the Gutenberg–Richter (GR) law.