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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.

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Abiotic stress on seed germination and plant growth of Zeyheria tuberculosa

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Journal of Forestry Research 2023年第5期34卷 1511-1522页

作者： Robson Luis silva de Medeiros Rinaldo Cesar de Paula joao Vitor Oliveira de Souza joao Pedro Peixoto Fernandes department of Agricultural Sciences School of Agricultural and Veterinarian SciencesSao Paulo State University(Unesp)14884-900JaboticabalSao PauloBrazil

Zeyheria tuberculosa(Vell.)Bureau ex *** among the Brazilian flora threatened with *** has high-quality wood and can be used to recover herbicidecontaminated ***,abiotic stresses can harm seed germination and seedling development under adverse conditions and need to be understood to improve autochthonous or indigenous biodiversity conservation and strengthen reforestation *** study evaluated the effects of temperature,water and saline stress on *** seed germination and water stress on seedling *** laboratory experiments evaluated germination under:(1)different temperatures(20,25,30,35 and 40℃);(2)different water potentials simulated with polyethylene glycol(PEG6000)at 25 and 30℃;and,(3)different osmotic potentials simulated with NaCl at 25 and 30℃.In addition,a greenhouse experiment subjected seedlings to five water regimes(20%,35%,50%,65%and 80%of maximum substrate water holding capacity).In the laboratory,seedling biometry and germination were evaluated,while physiological and morphological parameters were assessed in the *** potential of seeds increased at 25 and 30℃.Germination and vigor decreased as water and saline stresses *** tolerance thresholds for water and salt stresses were-0.6 and-0.4 MPa,*** the greenhouse,the most restrictive water regimes reduced seedling physiological and morphological *** development was compromised at moisture levels below50%field capacity.

关键词： Bignoniaceae Climate change Ipê-felpudo Ipê-preto Water stress

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development of a Methodology for determination and Analysis of Thermal Displacements of Machine Tools Using Finite Elements Method and Artificial Neural Network

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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.

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Fractionation of rare earth and other trace elements in crabs,Ucides cordatus,from a subtropical mangrove affected by fertilizer industry

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Journal of Environmental Sciences 2017年第4期29卷 69-76页

作者： Alice bosco-Santos Wanilson Luiz-silva Emmanoel Vieira da silva-Filho Monique Dias Corrêa de Souza Elton Luiz Dantas Margareth Sugano Navarro State University of Campinas (UNICAMP) Institute of Geosciences Department of Geology and Natural Resources Campinas Sao Paulo 13083870 Brazil . Fluminense Federal University (UFF) Institute of Chemistry Department of Geochemistry Niteroi Rio de Janeiro 24900970 Brazil University of Brasília(UnB) Institute of Geosciences Department of Geology Brasflia Distrito Federal 70910900 Brazil

Fractionation of rare earth elements（REE） and other trace metal concentrations（Th, U, Cd,Cr, Cu, Ni, Pb, and Zn） between mangrove sediments and claw muscles and shells of male crabs（Ucides cordatus） from a subtropical estuary highly impacted by fertilizer industry activities was investigated. This is the first record of REE distribution in these organisms,and the results showed higher accumulations of these metals, U and Th in shells, probably related to the replacement of Ca during molting. Contents of Cd, Cr and Ni were similar in both tissues, but Cu, Zn and Pb were mostly accumulated in the claw muscle with concentrations above those considered safe for human consumption according to the Brazilian legislation. REE fractionation was different in the analyzed tissues being softer in the shells. The results provided evidences that the water absorbed during molting controls the chemistry of REE in shells. In contrast, the chemistry of REE in the claw muscle, in which was observed preferential absorption of light REE, is controlled by diet. REE fractionation obtained for the claw muscles was closely correlated to the observed in the contaminated substrate and in materials related to the production of phosphate fertilizers（contamination source）, which supports their transference to this Ucides cordatus tissue without fractionation by the ingestion of sediments. Our results showed the potential use of crab tissues for monitoring REE and trace element sources in mangrove areas, with claw muscle exhibiting the contaminant source fingerprint.

关键词： Rare earth elements Trace metals Fertilizer contamination Crabs

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Appropriateness of the study of iron deficiency anemia prior to referral for small bowel evaluation at a tertiary center

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World Journal of Gastroenterology 2017年第24期23卷 4444-4453页

作者： Jaime Pereira Rodrigues Rolando Pinho Joana silva Ana Ponte Mafalda Sousa joao Carlos silva joao Carvalho department of Gastroenterology Centro Hospitalar Vila Nova de Gaia/EspinhoRua Conceicao FernandesVila Nova de Gaia

To evaluate the adequacy of the study of iron deficiency anemia (IDA) in real life practice prior to referral to a gastroenterology department for small bowel evaluation. METHODSAll consecutive patients referred to a gastroenterology department for small bowel investigation due to iron deficiency anemia, between January 2013 and december 2015 were included. Both patients referred from general practitioners or directly from different hospital departments were selected. Relevant clinical information regarding prior anemia workup was retrospectively collected from medical records. An appropriate pre-referral study was considered the execution of esophagogastroduodenoscopy (EGD) with Helicobacter pylori (H. pylori) investigation, colonoscopy with quality standards (recent, total and with adequate preparation) and celiac disease (CD) screening (through serologic testing and/or histopathological investigation). RESULTSA total of 77 patients (58.4% female, mean age 67.1 ± 16.7 years) were included. Most (53.2%) patients were referred from general practitioners, 41.6% from other hospital specialties and 5.2% directly from the emergency department. The mean pre-referral hemoglobin concentration was 8.8 ± 2.0 g/dL and the majority of anemias had microcytic (71.4%) and hypochromic (72.7%) characteristics. 77.9% of patients presented with an incomplete pre-referral study: EGD in 97.4%, with H. pylori investigation in 58.3%, colonoscopy with quality criteria in 63.6%, and CD screening in 24.7%. Patients with an appropriate study at the time of referral were younger (48.7 ± 17.7 vs 72.3 ± 12.3 years, P dertaken in 72.7% of patients, with a more frequent evaluation in patients with a quality colonoscopy at referral (78.6% vs 23.8%); P ded as the likely cause of IDA was small bowel angioectasia (18.2%) but additional causes were also found in the upper and lower ga

关键词： Iron deficiency anemia Colonoscopy Celiac disease Esophagogastroduodenoscopy Helicobacter pylori Small bowel

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Assessing tree crown fire damage integrating linear spectral mixture analysis and supervised machine learning on Sentinel-2 imagery

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International Journal of Digital Earth 2023年第1期16卷 3162-3198页

作者： Giandomenico de Luca Giuseppe Modica joao M.N.silva Salvatore Praticò JoséM.C.Pereira Dipartimento di Agrari1 Universitàdegli Studi Mediterranea di Reggio Calabri1Reggio Calabri1Italy Dipartimento di Scienze veterinarie Universitàdegli Studi di Messin1Messin1Italy Forest Research Centre School of AgricultureUniversity of LisbonLisbonPortugal

Crown fire damage is a mixture of three principal fire-related components:charred material,scorched foliage,and unaltered green *** study estimated the abundance of these physical alterations in two immediate post-fire Mediterranean forest contexts(Portugal and Italy)by applying linear spectral mixture analysis(LSMA)on Sentinel-2 *** tree crowns fire damage was subsequently mapped,integrating fractional abundance information in a random forest(RF)algorithm,comparing the accuracy resulting from the adoption of generic or image spectral libraries as the primary investigative *** image-derived endmembers resulted in more effectiveness in terms of fire-related components abundance quantification(LMSAderived RMSEderived information was *** environmental heterogeneity of the two study areas affected the fire severity gradients,with a prevalence of the charred(PT)(45–46%)and green class(IT)(44–53%).Post-fire temporal monitoring was initialized by applying the proposed strategies,and the preliminary results showed a positive recovery trend in forest vegetation from the first year following the fire event,with a reduced charcoal predominance and an increasing proportion of green components.

关键词： Post-fire assessment fire severity post-fire vegetation recovery random forest(RF) scikit-learn fraction image extraction spectral unmixing endmembers crown fire damage mapping fully constrained least squares pixel purity index

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HEMITHYROIdeCTOMY PERFORMED WITH ACUPUNCTURE ANESTHESIA:A CASE REPORT

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Journal of Integrative Medicine 2014年第3期 312-313页

作者： joao bosco silva Ana Moreira joao Padovani Rassen Saidah Rio Preto Medical School

Purpose: To observe the procedure of hemithyroidectomy performed using only acupuncture ***: Female, 68 years old, thyroid nodule, signed a consent ***: Points needled: PC6, LI4, LI18, Yintang and Dumai *** performed in the first three pairs of points, frequency of 5 Hz, in the mode of continuous wave for a period of 10 min, high *** these 10 min, intensity was fully decreased, the frequency was changed to 100 Hz, the wave was changed to disperse-dense, and intensity was increased again, now for 20 *** received only 5 mL of 2% lidocaine applied with insulin needle in the area of the incision; it was the only medication that the patient received in the procedure because acupuncture was shown to be ineffective for anesthesia of the ***: Surgery was performed in a conventional manner carefully because the method allows analgesia and not full anesthesia, and the patient may have the sense of touch and *** remained awake and communicative and venous access was maintained just for an *** procedure took 75 min, 30 min of analgesic induction and 45 min of surgery, which drew attention for its little *** patient, who was awake and communicative, just reported discomfort in the operated area, mainly due to manipulation and prolonged neck *** received 1 g of cefazolin, 100 mg of ketoprofen and 1 g of dipyrone, the standard procedure of *** surgery, she immediately went to the room and was released the next ***: Comparing with the conventional surgery(intubation, risk of nerve injury, recovery), our method has great *** limitations, a prolonged induction time and a cooperative patient who knows acupuncture and is confident in the technique was *** may be an optimal option to that kind of patient who may not undergo the conventional anesthesia.

关键词： HEMITHYROIdeCTOMY PERFORMED WITH ACUPUNCTURE ANESTHESIA

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MULTIOBJECTIVE ROUTING IN MULTISERVICE MPLS NETWORKS WITH TRAFFIC SPLITTING-A NETWORK FLOW APPROACH

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Journal of Systems Science and Systems Engineering 2015年第4期24卷 389-432页

作者： Rita Girao-silva Jose Craveirinha joao Climaco M.Eugenia Captivo department of Electrical and Computer Engineering University of Coimbra Polo ⅡPinhal de Marrocos P-3030-290 Coimbra Portugal Institute of Computers and Systems Engineering of Coimbra(INESC-Coimbra)R.Antero de Quental 199 P-3000-033 Coimbra Portugal Centro de Investigacao Operacional Faculdade de CienciasUniversidade de Lisboa Campo GrandeBloco C6Piso 4 P-1749-016 Lisboa Portugal

A multiobjective routing model for Multiprotocol Label Switching networks with multiple service types and traffic splitting is presented in this paper. The routing problem is formulated as a multiobjective mixed-integer program, where the considered objectives are the minimization of the bandwidth routing cost and the minimization of the load cost in the network links with a constraint on the maximal splitting of traffic trunks. Two different exact methods are developed for solving the formulated problem, one based on the classical constraint method and another based on a modified constraint method. A very extensive experimental study, with results on network performance measures in various reference test networks and in randomly generated networks, is also presented and its results are discussed.

关键词： Routing models multiobjective optimization telecommunication networks network flowapproach traffic splitting

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Yet Another Intelligent Code-Generating System： A Flexible and Low-Cost Solution

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Journal of Computer Science & Technology 2018年第5期33卷 940-965页

作者： joao Fabricio Filho Luis Gustavo Araujo Rodriguez Anderson Faustino da silva department of Informatics State University of Maringd Maringd-PR 87020-900 Brazil Federal University of Technology -- Parand Campo Mourao-PR 87301-899 Brazil

Modern compilers apply various code transformation algorithms to improve the quality of the target code. However, a complex problem is to determine which transformation algorithms must be utilized. This is difficult because of three reasons： a number of transformation algorithms, various combination possibilities, and several configuration possibil- ities. Over the last few years, various intelligent systems were presented in the literature. The goal of these systems is to search for transformation algorithms and thus apply them to a certain program. This paper proposes a flexible, low-cost and intelligent system capable of identifying transformation algorithms for an input program, considering the program＇s specific features. This system is flexible for parameterization selection and has a low-computational cost. In addition, it has the capability to maximize the exploration of available computational resources. The system was implemented under the Low Level Virtual Machine infrastructure and the results indicate that it is capable of exceeding, up to 21.36%, performance reached by other systems. In addition, it achieved an average improvement of up to 17.72% over the most aggressive compiler optimization level of the Low Level Virtual Machine infrastructure.

关键词： compiler code transformation iterative compilation knowledge representation machine learning

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Neoarchean atmospheric chemistry and the preservation of S-MIF in sediments from the São Francisco Craton

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Geoscience Frontiers 2022年第5期13卷 207-226页

作者： Alice bosco-Santos William Patrick Gilhooly Ⅲ Paola de Melo-silva Fotios Fouskas Amaury Bouyon João Gabriel Motta Mauricio Rigoni Baldim Wendell Fabricio-silva Pascal Philippot Elson Paiva Oliveira department of Geology and Natural Resources University of CampinasCampinasSP 13083855Brazil department of Earth Sciences Indiana University-Purdue University IndianapolisIndianapolisINUSA Institut de Physique du Globe de Paris Universitéde ParisCNRS-UMR 715475005 Paris Cedex 05France Vizlab-X-Reality and GeoInformatics Lab UNISINOSSão LeopoldoRS 93022-750Brazil Geosciences department Federal University of Mato GrossoCuiabáMTBrazil Geosciences Institute University of BrasiliaBrasíliaDistrito Federal 70910-900Brazil Institute of Geography and Geology University of Würzburg97074 WürzburgGermany Géosciences Montpellier Universitéde MontpellierCNRSUniversitédes AntillesMontpellierFrance Institute of Astronomy Geophysicsand Atmospheric SciencesUniversity of São PauloRua do Matão 1226São PauloBrazil

Sulfur mass-independent fractionation(S-MIF)preserved in Archean sedimentary pyrite is interpreted to reflect atmospheric *** ranges in Δ^(33)S that expanded into larger fractionations leading up to the Great Oxygenation Event(GOE;2.45–2.2 Ga)are disproportionately represented by sequences from the Kaapvaal and Pilbara *** patterns of S-MIF attenuation and enhancement may differ from the timing and magnitude of minor sulfur isotope fractionations reported from other cratons,thus obscuring local for global sulfur cycling *** expanding the Δ^(33)S record to include the relatively underrepresented São Francisco Craton in Brazil,we suggest that marine biogeochemistry affected S-MIF preservation prior to the *** an early Neoarchean sequence(2763–2730 Ma)from the Rio das Velhas Greenstone Belt,we propose that low δ^(13)Corg(ded iron formation reflect the marine diagenetic process of anaerobic methane *** overlying black shale(TOC up to 7.8%)with higher δ^(13)Corg(-33.4‰to-19.2‰)and expanded Δ^(33)S(2.3‰±0.8‰),recorded oxidative sulfur cycling that resulted in enhance preservation of S-MIF input from atmospheric sources of elemental *** sequence culminates in a metasandstone,where concomitant changes to more uniform δCorg(-30‰to--25‰),potentially associated with the RuBisCO I enzyme,and near-zero Δ^(33)S(-0.04‰to 0.38‰)is mainly interpreted as evidence for local oxygen *** placed in the context of other sequences worldwide,the Rio das Velhas helps differentiate the influences of global atmospheric chemistry and local marine diagenesis in Archean biogeochemical *** data suggest that prokaryotic sulfur,iron,and methane cycles might have an underestimated role in pre-GOE sulfur minor isotope records.

关键词： S-MIF preservation Archean atmospheric chemistry GOE São Francisco Craton

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