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Sequential deposition method of TiO2/CH3NH3PbI3 films for solar cell application

IOP Conference Series: Materials Science and engineering 2019年第1期659卷

作者： A E R T P Oliveira F Bonatto A K Alves C Fragassa Post-Graduation Program in Mining Metallurgy and Materials Engineering (PPGE3M) Federal University of Rio Grande do Sul Osvaldo Aranha 99 90035-190 Porto Alegre Brazil InterDepartmental Centre for Industrial Research on Advanced Applications in Mechanical Engineering & Materials Technology Alma Mater Studiorum University of Bologna viale Risorgimento 2 40136 Bologna Italy

Seeking to study innovative solar cell compositions with the goal to reach the highest energy efficiency level attainable, the aim of this study was to develop a route to obtain a solar cell composed by hybrid perovskite (CH3NH3PbI3) using a sequential deposition method through the techniques of spin-coating and immersion. Initially, the deposition of PbI2 thin film of was performed on a FTO/glass substrate coated with TiO2, which was subsequently converted into perovskite crystals through spin coating using a CH3NH3I solution. The influence of the PbI2 layer thickness on the formation of CH3NH3PbI3 crystals was evaluated. The hydrophilic characteristic of TiO2 affects the distribution of the crystals nucleation sites, since PbI2 possesses a non-polar liquid characteristic. The characterization of the perovskite thin films showed that thickness affects directly the bandgap and the surface morphology, revealing the presence of dendritic structures and acicular crystals. Both growth and coverage increased for thinner layers of PbI2. It was also possible to observe an increased uniformity in the film for smaller PbI2 layers.

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Computing derivatives in interval type-2 fuzzy logic systems trained by steepest descent method for fault classification in a switch machine

Computing derivatives in interval type-2 fuzzy logic systems...

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IEEE International Conference on Fuzzy Systems (FUZZ-IEEE)

作者： Eduardo P. de Aguiar Renan P. F. Amaral Marley M. B. R. Vellasco Moisés V. Ribeiro Industrial and Mechanical Engineering Departmant and Electrical Engineering Post-Graduation Program Federal University of Juiz de Fora Juiz de Fora/MG Brazil Electrical Engineering Department Pontifical Catholic University of Rio de Janeiro Rio de Janeiro/RJ brazil

ISBN: (纸本)9781509060351

A switch machine is an electromechanical device that allows railway trains to be guided from one track to another. Among all possible faults that can occur in a switch machine, the three mains ones are: lack of lubrication, lack of adjustment and malfunction of a component. Aiming to classify these faults, an important contribution of this work is to address the height type-reduction and interval singleton type-2 fuzzy logic system derivatives. The computational simulations are performed with real data set provided by a Brazilian company of the railway sector. The obtained results are compared with other models reported in the literature (Bayes theory, multilayer perceptron neural network and type-1 fuzzy logic system), demonstrating the effectiveness of the proposed classifier and revealing that the proposal is able to properly handle with uncertainties associated with the measurements and with the data that are used to tune the parameters of the model. In addition, the convergence speed and performance analysis show that the proposed interval singleton type-2 fuzzy logic system is attractive for classifying faults in a switch machine.

关键词： Fuzzy logic Switches Feature extraction Mathematical model Lubrication Training Uncertainty

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The effect of energy efficiency increase on a PV plant with a non-conventional energy storage system income

The effect of energy efficiency increase on a PV plant with ...

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Power Electronic and Drive Systems and Technologies Conference (PEDSTC)

作者： Ali Moallemi Luiz Machado Ricardo Nicolau Nassar Koury Fabricio Jose Pacheco Pujatti Program of Post-Graduation in Mechanical Engineering Federal University of Minas Gerais (UFMG) Belo Horizonte Program of Post-Graduation in Mechanical Engineering Universidade Federal de Minas Gerais Belo Horizonte MG BR

This Photovoltaic (PV) plants are widely used to produce power in either large or small scales all around the world. In addition, compressed air energy storage (CAES) system has attracted considerable attention as one of the most efficient candidates for large scales energy storage applications in the recent years. In this work, detailed energy and exergy analysis of a 100 MWp grid connected PV plant equipped with a CAES system is carried out. The PV plant is assumed to be located in Brazil. The formulations related to the first and the second laws of thermodynamic for all components as well as detailed solar engineering formulations for both the PV farm and the solar heating unit are presented. The performance of the power plant is comprehensively investigated for one entire year in real circumstances. The results revealed that the annual average exergy and energy efficiencies of the power plant are 17.9% and 16.2%, respectively and for 1% energy efficiency enhancement the power plant, the annual income increases almost 4 million USD.

关键词： Solar heating Power generation Storage tanks Reservoirs Thermodynamics Radiation effects

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Uncertainty evaluation on aperture area measurement for radiometric traceability

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Journal of Physics: Conference Series 2018年第8期1065卷

作者： P B Costa W S Barros F O Baldner Department of Mechanical Engineering Federal University of Minas Gerais Av. Antonio Carlos 6627 Campus Pampulha Belo Horizonte/MG - Brazil Dimensional Laboratory National Institute of Metrology Quality and Technology (Inmetro) Av. Nossa Senhora das Graças 50 Xerém Duque de Caxias/RJ - Brazil Fluminense Federal University Post-Graduation Program on Mechanical Engineering - UFF-PGMEC Rua Passo da Patria 156 Niterói/RJ Brazil

In computer vision applications one of important step, when the aim of the system is to obtain a measurement result, is the uncertainty of measurement evaluation. Involving image processing and analysis for measurement requires a specific study of all input quantities and its contribution for expanded uncertainty. In this paper will be described all contributions and how each one affect the measurement result, including contributions from algorithms of image processing. Finally this work compares the uncertainty obtained with a previous result from Monte Carlo simulation for analysis validation.

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Assessment of Trabecular Bones Microarchitectures and Crystal Structure of Hydroxyapatite in Bone Osteoporosis with Application of the Rietveld Method

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Procedia engineering 2015年 110卷 8-14页

作者： J.M.D.A. Rollo R.S. Boffa R. Cesar D.C. Schwab T.P. Leivas University of São Paulo – São Carlos School of Engineering Materials Engineering Department São Carlos ZIP CODE 13566-590 Brazil Interunits Post Graduation Program – Materials Engineering Department EESC FMRP IQSC USP ZIP CODE 13566-590 Brazil Mechanical Engineering Post Graduation Program EESC USP ZIP CODE 13566-590 Brazil DCS English Consultancy Services ZIP CODE 13560-230 São Carlos – Brazil* Hospital das Clínicas São Paulo ZIP CODE 5403-000 Brazil

The term crystal structure is understood as a set of atoms periodically distributed in space, forming a lattice. The composite material, bone, contains an organic part consisted of collagen and an inorganic part consisted predominantly of hydroxyapatite crystals, having the molecular formula Ca 10 (PO4) 6 (OH) 2 in its unit cell. The crystal structure of hydroxyapatite can indicate the trabecular bone quality, by the identification of crystallite size, microhardness, microstrain and ratio of calcium and phosphorus in bones of three types: normal, osteopenic or osteoporotic. Osteoporosis is defined by the National Institute of Health as a skeletal disorder characterized by compromised bone strength and increased risk of fracture. Dried trabecular bones of vertebrae L1 columns of nine human cadavers from the São Paulo City Morgue were used. Before sample collection, they were pre-divided into three groups: normal, osteopenic or osteoporotic, through quantitative ultrasound of the calcaneus. The characterization of the three types of bones was made by electron microscopy scanning, microanalysis by energy dispersive spectrometry, microhardness and powder X-ray diffraction with application of the Rietveld method. The results showed a decrease of the crystallite size, hardness, ratio of calcium and phosphorus, trabecular number and bone density and an increase in microstrain values suggesting greater fragility and disruption in the crystalline structure of hydroxyapatite in osteopenic and osteoporotic bone. Microstructural characterization of hydroxyapatite crystals in dry trabecular bone could differentiate the three types of bones (normal, osteopenic and osteoporotic) and supplement assessment of osteoporosis, with an emphasis on bone quality.

关键词： Crystal structure Hydroxyapatite Human bone Osteopenia Osteoporosis Rietveld Refinenmen

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The Effect of Adding Ni and Sn to Pd Catalysts on the Direct Ethanol Fuel Cell Performance

The Effect of Adding Ni and Sn to Pd Catalysts on the Direct...

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2014 International Conference on Energy, Environment and Materials engineering(EEME 2014)

作者： A.M.SHEIKH E.L.SILVA P.S.CORREA T.L.MENEZES C.F.MALFATTI Department of Mechanical Engineering South Valley University Corrosion Research Laboratory (LAPEC) Post-graduation Program in MiningMetallurgical and Materials Engineering Faculdade da Serra Gaúcha – FSG

Direct ethanol fuel cells DEFCs can convert chemical energy from ethanol electrooxidation directly to *** significant challenge for DEFC is the need for highly active surface catalysts for ethanol oxidation reaction *** this work,the impregnation-reduction method is used to synthesize binary Pd Ni and Pd Sn catalysts supported on functionalized carbon（Vulcan XC-72） with HNO to accelerate the EOR in alkaline electrolyte.X-ray diffraction XRD,cyclic voltammetry CV,and chronoamperometry CA tests were undertaken to characterize the structure and to evaluate the electrochemical performance of different *** was observed that Pd-Sn catalyst has achieved good alloying results enhancing the EOR activity;however the addition of Ni to Pd was even higher though synthesizing Pd and Ni has not proved strong alloying,and the best results were observed for the PdNi/C catalyst.

关键词： DEFC Ethanol oxidation Alkaline medium Pd catalyst

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Balancing a system using variable speed drivers

Balancing a system using variable speed drivers

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11th IFAC Workshop on Intelligent Manufacturing Systems, IMS 2013

作者： Natalia, Oliveira L. Cícero, De Paula A.B. Herman, Lepikson A. Post-Graduation Program in Mechatronics Federal University of Bahia Salvador Brazil Center of Technological Qualification in Industrial Automation Federal University of Bahia Salvador Brazil Mechanical Engineering Department Federal University of Bahia Salvador Brazil

ISBN: (纸本)9783902823335

Unbalanced mechanical systems are always of great concern to engineers because of, the implications on the reliability of the systems. This paper presents two approaches to handling the problem in mechanical systems equipped with electrical motors driven by variable speed drivers. The two methods are able to verify the imbalance of the system based on the cyclic load factor (CLF) and on the discrete Fourier transform (DFT), both using the torque signal obtained from the drive. Algorithms were developed to obtain the necessary parameters from the drive and then converted into ladder programs able to be embedded in the drivers so that real time balancing control can be achieved. Experimental results demonstrate the possibility of assisting the balancing of mechanical systems based on the developed algorithms. Among the advantages of maintaining a balanced system using the present approach is preventing equipment wear, increasing the useful life and reducing maintenance costs. © 2013 IFAC.

关键词： Discrete Fourier transforms

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Rational use of idleness in manufacturing cells 22

Rational use of idleness in manufacturing cells

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22nd International Conference on Production Research, ICPR 2013

作者： Coppini, Nivaldo Lemos Da Silva Lourenço, Wilson De Souza, Edson Melo Hassui, Amauri Carvalho, Alexandre Augusto Martins Industrial Engineering Post Graduation Program Nove de Julho University Avenida Francisco Matarazzo-612 São Paulo SP05001-100 Brazil College of Mechanical Engineering University of Campinas CP 6122 Campinas SP Brazil

Industrial environments are highly competitive. Factors such as: agility, flexibility, service delivery, quality and prices are competitive advantages sought by organizations. In this scenario, proposed optimizations that address such factors are of particular interest of planning process engineers. The procedure proposed in this work comes to search for net direct finance and market increasing of a given company, which could contribute to its healthy financial structure. This paper aims to propose to use the concepts of the theory of constraints and industrial costs. The research method can be considered as exploratory, since it uses traditional concepts of everyday factory. Based on the traditional concepts of costs, planning and production scheduling, this paper aims to propose a procedure to identify, analyze and stratify the idleness and costs that are inherent in the factory system. The high point of this research is because the use of machine idle time means the full utilization of all available factory system. When idleness of these machines is used, the result is net income for the company excepting only the raw material used.

关键词： Production control

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Hard Turning of Sintered Cemented Carbide Parts: A Shop Floor Experience

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Procedia CIRP 2013年 8卷 368-373页

作者： N.L. Coppini A.E. Diniz M. Bonandi E.M. De Souza E.A. Baptista College of Mechanical Engineering - University of Campinas CP 6122 – Campinas SP Brazil Nove de Julho University Industrial Engineering Post Graduation Program Av. Francisco Matarazzo 612 – Barra Funda São Paulo SP 05001- 100 Brazil

Machining hardened steel has been a recurring issue in the literature when tools with defined geometry cutting edges are used. It is well known the use of cemented carbides to produce cutting tools. It is also well known that this occurs before applying sintering process, to facilitate the production of special tools or specific kind of parts, which will be sintered later. What is not very known is the cutting of cemented carbides to produce special kind of parts used when high hardness, high compression resistance, high surface quality and tight tolerances are demanded. To meet such requirements is necessary to machine the pieces after sintering. Despite being a satisfactory alternative, the grinding process could not meet such requirements and, moreover, probably is more expensive. The purpose of this work is to develop an experience that, by gathering data from an industry shop floor that choose not to be identified, show the feasibility of turning sintered cemented carbide. The results showed that besides to be viable, turning process could machine workpieces with tight tolerances and excellent surface roughness.

关键词： Hard machining Turning vs Grinding Cemented Carbide

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Balancing a system using variable speed drivers

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IFAC Proceedings Volumes 2013年第7期46卷 122-127页

作者： Oliveira L. Natalia de Paula A.B. Cícero Lepikson A. Herman Post-graduation program in Mechatronics Federal University of Bahia Salvador Brazil (Tel: 71-3283-9471) Center of technological qualification in industrial automation Federal University of Bahia Salvador Brazil (Tel:71-3283-9755) Mechanical Engineering Department Federal University of Bahia Salvador Brazil

关键词： Balancing system Cyclic load factor Discrete Fourier transform Variable speed drivers

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