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Journal of Mechanics Engineering and Automation 2014年第6期4卷 488-498页

作者： Romualdo Figueiredo de Sousa Fracisco Augusto Vieira da Silva Joao Bosco Aquino Silva jose carlos de lima junior department of Mechanical Engineering Federal University of Paraiba Joao Pessoa 58051-900 Brazil

In the processes of manufacturing, MT （machine tools） plays an important role in the manufacture of work pieces with complex and high dimensional and geometric accuracy. Much of the errors of a machine tool are those which are thermally induced which are from internal and external heat sources acting on the machine. In this paper, a methodology for determining and analyzing the thermal deformation of machine tools using FEM （finite element method） and ANN （artificial neural networks） is presented. After modeling the machine using FEM is defined the location of the heat sources, it is possible to obtain the temperature gradient and the corresponding thermal deformation at predetermined periods. Results obtained with simulations using the software NX.7.5 showed that this methodology is an effective tool in determining the thermal deformation of the machine, correlating the temperature reading at strategic points with volumetric deformation at the tool tip. Therefore, the thermal analysis of the errors in the pair tool part can be established. After training and validation process, the network will be able to make the prediction of thermal errors just stating the temperature values of specific points of each heat source, providing a way for compensation of thermally induced errors.

关键词： Thermal displacement machine tool finite element method artificial neural network.

Application of NURBS for Obtaining Free Form Curves and Surfaces in Spur and Helical Gears by Using CMM （Coordinate Measurement Machine）

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Journal of Mechanics Engineering and Automation 2014年第5期4卷 432-440页

作者： Luiz Henrique Melo Silva Nobrega Verilton Nunes da Silva jose carlos de lima junior Joao Bosco de Aquino Silva Igor Lucena Peixoto Andrezza Rafael Franklin Alves Silva department of Mechanical Engineering Federal University of Paraiba Jo6o Pessoa 58051-900 Brazil department of Mechanical Engineering Federal Institute of Bahia SimOes Filho 43700-000 Brazil Informatics Center Federal University of Paraiba Jo6o Pessoa 58051-900 Brazil department of Mechanical Engineering Federal Institute of Paraiba Jo6o Pessoa 58900-000 Brazil

Currently, engineering processes require reduced manufacturing time and low cost, in addition to the growing demand for workpieces with high accuracy. Workpieces with complex geometries and free forms has been a common practice in industries from different sectors such as： automotive, aeronautics, bioengineering among others. One way to satisfy the market requirements satisfactorily is making measurements more efficient to make the production process faster, in other words, it is necessary to make the inspection system more accurate and flexible. The coordinate measuring evolved over the past three decades and today it is the technology that best meets the requirements of modem manufacturing through CMMs （coordinate measurement machines）. The CMMs are important tool for design, fabrication and inspection of manufactured products, also used in the application of reverse engineering. These machines are also used by engineers in order to produce an accurate digital model in a virtual space for later use in CAD （computer-aided design）/CAM （computer-aided manufacturing）. It is worth mentioning that the accuracy of the modeling process of given piece depends on the number of control points that are captured on the workpiece surface. Consequently, the laser inspection systems are the best tools for use in reverse engineering, but more expensive when compared to contact measurement systems that use the TTP （touch trigger probe）, also used by CMMs. In this case, this paper aims to present an approach based on NURBS （non-uniform rational B-splines） to obtain free form curves and surfaces from a group of points obtained by using a contact sensor, the touch trigger probe. NURBS is an important mathematical tool and consists of generalizations of Bezier curves and surfaces and B-splines. The approach proposed in this paper can be applied for obtaining free form curves and surfaces in spur and helical gears. Experimental results obtained by measuring spur gears showed that the NU

关键词： Coordinate measurement machine touch trigger probe NURBS reverse engineering.

Autoregressive spatial analysis and individual tree modeling as strategies for the management of Eremanthus erythropappus

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Journal of Forestry Research 2016年第3期27卷 595-603页

作者： Henrique Ferraco Scolforo jose Roberto Soares Scolforo jose Marcio de Mello Anto nio carlos Ferraz Filho Diogo Francisco Rossoni Thiza Falqueto Altoe Antonio Donizette Oliveira Renato Ribeiro de lima department of Forest Science Federal University of Lavras PO Box: 3037 Lavras MG 37200-000 Brazil department of Statistics State University of Maringa Av. Colombo 5.790 Jd. Universitario Bloco E90 Maringa PR 87020-900 Brazil department of Statistics Federal University of Lavras PO Box: 3037 Lavras MG 37200-000 Brazil

The objectives of this study were to apply statistical techniques to discriminate fertilization treatments of Eremanthus erythropappus（DC.） Mac *** autoregressive modeling, and to develop individual tree models for diameter and crown area（CA） projection to define management strategies for candeia plantations subjected to different fertilization treatments. This is an important tree species originating from the Brazilian Atlantic Rain forest and Savannah biomes, intensively used in the cosmetic industry. Nonetheless, to date, research has not addressed the management of natural stands or plantations of the species. Our experiment was located in Baependi, Minas Gerais, Brazil, and comprised of four randomized blocks and 13 treatments. The treatments consisted of 12 different regimes of fertilization plus a control. Each sample plot was composed of 50 plants plus two border plants in a planting spacing of 2.5 9 2.0 m and undergoing pruning at 5 and 6 years of age. Starting in the second year, total tree height（H） and circumference（at 1.30 m from the ground or breast height, CBH） were measured every 6 months. Starting in the fifth year CA was measured. Tree growth varied by fertilization *** were detected by using an autoregressive approach, considering that standard statistical methods were not powerful enough to detect significant *** growth groups were formed, and maximum growth was obtained for treatment 10（NPK, 8-28-16）. Management guidelines are provided based on individual tree models for different fertilization levels.

关键词： Management strategies Candeia Fertilization level Brazil Crown area

SIR model applied in dynamics of COVID-19 contagion in S˜ao Lu´ıs-MA,Brazil

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International Journal of Modeling, Simulation, and Scientific Computing 2021年第3期12卷 99-111页

作者： Felix Silva Costa Italo jose lima de Sousa jose Adson Reis Santos department of Mathematics and Informatics State University of Maranhao Sao Luıs MA 65054-970Brazil

The dynamics of COVID-19 contagion investigated in S˜ao Lu′ıs-MA,Brazil,is based on the SIR model.S˜ao Lu′ıs was the first city in Brazil to implement the lockdown to control the *** SIR model’s definition and properties are presented in addition to the ways of estimating its *** estimation of their values is due to a database released on the Maranh˜ao State Health department website during the period March 20 to July 2,*** analysis of the proliferation of the disease shows the evolution of the COVID-19 in the *** graphs illustrate that result.

关键词： COVID-19 population dynamics SIR model

Integrated risk management: a Petrobras application in offshore well construction safety to minimize critical emergency disconnections

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Petroleum Science 2018年第2期15卷 421-431页

作者： Claudio Benevenuto de Campos lima Pedro Esteves Aranha jose Francisco Tebaldi de Castro Gilson Brito Alves lima Augusto Borella Hougaz Felipe de Souza Terra Petrobras department of Production Engineering Federal Fluminense University

In order to avoid mistakes and to save a great deal of time in analysis, an innovative methodology was developed that can analyze the well operations and rig characteristics involved to define the best emergency disconnect sequence （EDS） available. A solution was developed based on the characteristics of the rigs and blowout preventers （BOPs）, and six variables were considered that directly affect the choice of EDS. All possible combinations of 64 scenarios were analyzed, and the priority of choice of the EDS was defined empirically. This paper presents an approach to EDS risk management and examples of exposure time （time without riser safety margin and shear capability） for the same well, which can be lowered from 13% to 0.1%. The impact of this reduction is related to the ability of the BOP to cut some of the heavy casings, in addition to improved availability of EDS modes. This implementation opened up many possibilities for the performance of risk exposure analysis, enabling comparison of several BOP configurations of contracted rigs and selection of the best options. This innovative approach allowed a better management of the rig schedules, prioritizing safety aspects and making it possible to allocate the fleet in a systematic way.

关键词： Well safety Safety barriers Emergency disconnect sequence (EDS) Well control Kick Well design

An overview of the endogenous and environmental factors related to the Coffea arabica flowering process

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Beverage Plant Research 2021年第1期1卷 106-121页

作者： Marlon Enrique López Iasminy Silva Santos Raphael Ricon de Oliveira AndréAlmeida lima carlos HenriqueCardon Antonio Chalfun-junior Laboratory of Plant Molecular Physiology Plant Physiology SectorDepartment of BiologyFederal University of LavrasLavras-Minas GeraisBrazil37200-900

The transition of vegetative meristems to a reproductive state followed by floral development and flowering is a complex process regulated by many regulatory pathways that integrate(epi)genetic and environmental factors to guarantee the reproductive success in *** woody and perennial species,such as coffee trees,the extended life cycle reflects adaptive strategies,i.e.,two-year cycle,sequential flowering and bud latency during the winter,that ensure reproductive success in a variable *** dynamics of coffee flowering integrate multiple stimuli to induce morpho-physiological changes,especially during the reproductive *** discussed diverse stimuli which are directly and indirectly associated with molecular pathways related to the reproductive meristem transition and floral development until ***,we propose to redefine some concepts regarding coffee floral development,such as:i)a summary of genes possibly involved in the flowering pathways;ii)a new classification of buds by position in the node(B1-B4)to avoid misunderstandings with the uneven developmental stages;iii)comparative ABC model to Arabidopsis and tomato to allow evolutionary discussions of whorls development in Coffea *** this,we expect to collaborate to drive future studies towards coffee breeding and production,for example,improving floral bud activation,controlling the flowering time,anthesis synchronization to produce more homogeneous ripening fruits,reducing abortion or early flower openings,and increasing ***,we think that the explored relationship between physiological and molecular approaches during the coffee flowering may be extended to understand other tropical perennial species,especially those with asynchronous flowering behavior,and to understand evolutive aspects in Rubiaceae.

关键词： breeding process flowering

Complex derivatives valuation: applying the Least-Squares Monte Carlo Simulation Method with several polynomial basis

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Financial Innovation 2016年第1期2卷 1-14页

作者： Ursula Silveira Monteiro de lima carlos Patricio Samanez department of Industrial Engineering Pontifical Catholic University of Rio de JaneiroMarquês de São Vicente Street225/22453-900 GáveaRio de JaneiroBrazil

Background:This article investigates the Least-Squares Monte Carlo Method by using different polynomial basis in American Asian Options *** standard approach in the option pricing literature is to choose the basis *** comparing four different polynomial basis we show that the choice of basis interferes in the option's ***:We assess Least-Squares Method performance in pricing four different American Asian Options by using four polynomial basis:Power,Laguerre,Legendre and Hermite *** every American Asian Option priced,three sets of parameters are used in order to evaluate it ***:We show that the choice of the basis interferes in the option's price by showing that one of them converges to the option's value faster than any other by using fewer simulated *** the case of an Amerasian call option,for example,we find that the preferable polynomial basis is Hermite *** an Amerasian put option,the Power polynomial basis is *** empirical outcome is theoretically unpredictable,since in principle all basis can be indistinctly used when pricing the ***:In this article The Least-Squares Monte Carlo Method performance is assessed in pricing four different types of American Asian Options by using four different polynomial basis through three different sets of *** results suggest that one polynomial basis is best suited to perform the method when pricing an American Asian *** all basis can be indistinctly used when pricing the ***,our results does not confirm *** find that when pricing an American Asian put option,Power A is better than the other basis we have studied here whereas when pricing an American Asian call,Hermite A is better.

关键词： Complex derivatives valuation Least-Squares Monte Carlo Method Amerasian options Polynomial basis

A PCR and RFLP-based molecular diagnostic algorithm for visceral leishmaniasis

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Asian Pacific Journal of Tropical Medicine 2020年第2期13卷 62-70页

作者： Natalia Souza de Godoy Manoel Sebastiao da Costa lima-junior jose Angelo Lauletta Lindoso Vera Lucia Pereira-Chioccola Thelma Suely Okay Lucia Maria Almeida Braz Laboratorio de Parasitologia Médica Departamento de Moléstias Infecciosas e Parasitárias do Hospital das Clinicas HCFMUSPFaculdade de MedicinaUniversidade de Sao PauloSao PauloBrazil Laboratorio de Imunopatologia e Biologia Molecular-Instituto Aggeu Magalhaes/IAM-FIOCRUZ RecifeBrazil Laboratorio de Soroepidemiologia e Imunobiologia-FMUSP Sao PauloBrazil Laboratorio de Biologia Molecular de Parasitas e Fungos-Instituto Adolfo Lutz Sao PauloBrazil Laboratorio de Parasitologia-Instituto de Medicina Tropical de Sao Paulo-USP Sao PauloBrazil

Objective:To determine an algorithm for molecular diagnosis of visceral leishmaniasis(VL)by kinetoplast DNA(kDNA)(RV1/RV2)and internal transcriber spacer(ITS1)(LITSR/L5.8 S)polymerase chain reaction(PCR),complemented by ITS 1 PCR restriction fragment length polymorphism(RFLP),using peripheral blood or bone marrow aspirate from patients with suspected ***:Biological samples were submitted to the gold standard for the diagnosis of VL and molecular diagnosis represented by ITS 1 PCR,kDNA PCR,and ITS 1 PCR *** samples were obtained from seven groups:groupⅠ,82 samples from patients with confirmed VL;groupⅡ,16 samples from patients under treatment for VL;groupⅢ,14 samples from dogs with canine visceral leishmaniasis(CVL);groupⅣ,a pool of six experimentally infected sandflies(Lutzomya longipalpis);group V,18 samples from patients with confirmed tegumentary leishmaniasis(TL)and groupsⅥandⅦwere from control groups without ***:The following gold standard and molecular examination results were obtained for each of the seven groups:groupⅠ:parasitologic and immunochromatographic tests showed a sensitivity of 76.3%(61 of 80)and 68.8%(55 of 80),respectively,and a sensitivity of 97.6%(80 of 82)and 92.7%(76 of 82)by ITS1 and kDNA PCR,*** ITS1 PCR RFLP(HaeⅢ)analysis of the 80 positive samples,52.5%(42 of 80)generated three fragments of 180,70,and 50 bp,corresponding to the pattern of Leishmania infantum infantum;groupⅡ:negative for the parasitologic methods and positive for IrK39(100%,16 of 16),presented 12.5%(2 of 16)of positivity by ITS 1 PCR and 25.0%(4 of 16)by kDNA PCR;groupⅢ:positive in the parasitologic and serologic tests(100%,14 of 14),presented 85.7%(12 of 14)of positivity by ITS1 PCR and kDNA ***1 PCR RFLP showed that 83.3%(10 of 12)of the canine samples contained parasites with profiles similar to ***;groupⅣpresented amplifications by ITS1 PCR and kDNA ***1 PCR products were analyzed by RFLP,generating a profile similar to

关键词： Leishmania infantum Molecular diagnosis Visceral leishmaniasis PCR RFLP

Air Quality Monitoring and Its Implication on the Environmental Licensing Process in Brazil

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Journal of Environmental Protection 2014年第1期5卷 1-8页

作者： jose carlos de Moura Xavier Wilson Cabral de Sousa junior department of Water Resources and Environmental Sanitation Aeronautics Institute of Technology(ITA)Sao Jose dos CamposBrazil Sao Paulo State Environmental Company(CETESB) Sao PauloBrazil

In the state of Sao Paulo, Brazil, public policies regarding the air quality aimed at the welfare of the population are strongly dependent on monitoring conducted by the Sao Paulo State Environmental Company (CETESB), which can be influenced by faulty monitors and equipment support and cuts in power supply, among others. A research conducted from 1998 to 2008 indicated that a significant portion of the air quality automatic stations in the state of Sao Paulo did not meet the criterion of representativeness of measurements of PM10, NO2, O3, CO and SO2 concentrations which resulted in the classification of some municipalities as the nonattainment area, a situation evidenced for PM10 and O3 parameters. The network unavailability for each parameter was estimated and compared with the monitoring networks operated in Canada and the UK. This paper discusses the implications of the lack of representativeness of measurements in the environmental licensing process of pollution sources from 2008, when by the effect of state law, municipalities have been qualified according to their air quality nonattainment level.

关键词： Air Quality Monitoring Public Policies Environmental Licensing

19-year remotely sensed data in the forecast of spectral models of the environment

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International Journal of Digital Earth 2021年第8期14卷 1040-1066页

作者： Fernando Saragosa Rossi carlos Antonio da Silva junior JoséFrancisco de Oliveira-Júnior Paulo Eduardo Teodoro Luciano Shozo Shiratsuchi Mendelson lima Larissa Pereira Ribeiro Teodoro Auana Vicente Tiago Guilherme Fernando Capristo-Silva State University of Mato Grosso(UNEMAT) Alta FlorestaMato GrossoBrazil department of Geography State University of Mato Grosso(UNEMAT)SinopMato GrossoBrazil cFederal University of Alagoas(UFAL) MaceióAlagoasBrazil dFederal University of Mato Grosso do Sul(UFMS) Chapadão do SulMato Grosso do SulBrazil eAgCenter School of PlantEnvironmentaland Soil SciencesLouisiana State University(LSU)Baton RougeLouisianaUSA fPostgraduate Program in Agronomy Federal University of Mato Grosso(UFMT)SinopMato GrossoBrazil

The aims of this study were:i)to compare no-till areas in two municipalities located in different regions of Brazil,along with the influence on CO_(2)Flux and GPP,and ii)to verify the difference between environmental factors followed by the trends of these variables regarding future scenarios(ARIMA time-series model number).The study was carried out in two areas with different latitudes in the municipalities of Sinop-MT and Passo Fundo-RS,both in Brazil.A time series of 19 years was performed with data acquired by remote sensing from the following satellites:i)Landsat-8(OLI and TIRS),and ii)TERRA/AQUA(MODIS).The results propound that the spectro-temporal variables are directly influenced by soil management and agricultural practices over the observation time,with a satisfactory correlation in future predictions of the variables for the next ten years,in which presented that the variation of GPP and albedo values for the two study sites would gradually increase until 2028 and the temperature remained constant between the range of its seasonality,and CO_(2)Flux tends to decrease in its seasonality,indicating a higher CO_(2) absorption.

关键词： ARIMA numerical modeling remote sensing orbital products tillage