Multi-q Pattern Classification of Polarization Curves

Several experimental measurements are expressed in the form of one-dimensional profiles, for which there is a scarcity of methodologies able to classify the pertinence of a given result to a specific group. The polarization curves that evaluate the corrosion kinetics of electrodes in corrosive media are an application where the behavior is chiefly analyzed from profiles. Polarization curves are indeed a classic method to determine the global kinetics of metallic electrodes, but the strong nonlinearity from different metals and alloys can overlap and the discrimination becomes a challenging problem. Moreover, even finding a typical curve from replicated tests requires subjective judgement. In this paper we used the so-called multi-q approach based on the Tsallis statistics in a classification engine to separate multiple polarization curve profiles of two stainless steels. We collected 48 experimental polarization curves in aqueous chloride medium of two stainless steel types, with different resistance against localized corrosion. Multi-q pattern analysis was then carried out on a wide potential range, from cathodic up to anodic regions. An excellent classification rate was obtained, at a success rate of 90%, 80%, and 83% for low (cathodic), high (anodic), and both potential ranges, respectively, using only 2% of the original profile data. These results show the potential of the proposed approach towards efficient, robust, systematic and automatic classification of highly non-linear profile curves.Comment: 12 pages, 7 figure

Horizontal Pressures in Cylindrical Metal Silos and Comparison with Different International Standards

The focus of this research was to evaluate the horizontal pressures on a cylindrical metal silo of corrugated walls and flat bottom with 1.82m diameter and 5.4m high, and to compare the values with those obtained theoretically by the ISO 11697, EP 433 and AS 3774 standards. The silo was symmetrically filled and constant speed with wheat cv. soft red for two different height/diameter ratios (H/D) and was unloaded through three orifices with a diameter of 71.6mm, one concentric and two eccentrics. Horizontal pressures were measured on the walls of the silo at three positions using hydraulic type pressure cells. The results showed that shortly after the start of the unloading, there was a mass flow above the quota of H/D = 1.2, whereas below this quota funnel flow occurred. It can be said that the EP 433 standard was more appropriate to predict horizontal pressures in silos in H/D ratio = 1.0, with eccentric unloading. For the H/D ratio = 1.5, AS 3774 standard was the one that produced values closer to the experimental

Electron waves in chemically substituted graphene

We present exact analytical and numerical results for the electronic spectra and the Friedel oscillations around a substitutional impurity atom in a graphene lattice. A chemical dopant in graphene introduces changes in the on-site potential as well as in the hopping amplitude. We employ a T-matrix formalism and find that disorder in the hopping introduces additional interference terms around the impurity that can be understood in terms of bound, semi-bound, and unbound processes for the Dirac electrons. These interference effects can be detected by scanning tunneling microscopy.Comment: 4 pages, 7 figure

Magnetic resonance imaging of the temporomandibular joint acquired using different parameters

Introduction: Magnetic resonance imaging (MRI) is considered the examination of choice for the diagnosis of abnormalities in the TMJ. Considering the difficulty in defining and standardizing the diagnostic criteria, and the need for more accurate and reliable diagnosis of conditions in the TMJ, the aim of the present study was to compare three different MRI parameters: T1-weighted, T2-weighted and proton density–weighted in the diagnosis of changes in the temporomandibular joint.Materials and Methods: Fifty magnetic resonance imaging examinations of the temporomandibular joint (100 temporomandibular joints) were conducted according to a protocol that evaluates disc position, disc function and bone abnormalities. The images were obtained bilaterally in parasagittal sections in closed and open mouth positions in the three studied parameters Three trained oral radiologists assessed all the images. Reliability of the intra- and inter-examiner response was analyzed using the concordance test (Fleiss’ kappa; α = 0.05).Results: The reliability of the response patterns between observers for different protocols varied from very good to good. Observers were less constant in their response patterns when assessing proton density–weighted images. There was very good agreement for disc morphology, cortical bone and bone structures/functions; however, there was wide variation for medullary bone marrow signs.Conclusion: T2-weighted imaging was found to be the best examination to assess the medullary bone. For evaluating of disc morphology, cortical bone and bone structures/functions, any protocol is indicated once the protocol does not interfere with the analysis.Magnetic resonance imaging (MRI) is considered the examination of choice for the diagnosis of abnormalities in the TMJ. Considering the difficulty in defining and standardizing the diagnostic criteria, and the need for more accurate and reliable diagnosis of conditions in the TMJ, the aim of the present study was to compare three different MRI parameters: T1-weighted, T2-weighted and proton density–weighted in the diagnosis of changes in the temporomandibular joint. Fifty magnetic resonance imaging examinations of the temporomandibular joint (100 temporomandibular joints) were conducted according to a protocol that evaluates disc position, disc function and bone abnormalities. The images were obtained bilaterally in parasagittal sections in closed and open mouth positions in the three studied parameters Three trained oral radiologists assessed all the images. Reliability of the intra- and inter-examiner response was analyzed using the concordance test (Fleiss’ kappa; α = 0.05). The reliability of the response patterns between observers for different protocols varied from very good to good. Observers were less constant in their response patterns when assessing proton density–weighted images. There was very good agreement for disc morphology, cortical bone and bone structures/functions; however, there was wide variation for medullary bone marrow signs. T2-weighted imaging was found to be the best examination to assess the medullary bone. For evaluating of disc morphology, cortical bone and bone structures/functions, any protocol is indicated once the protocol does not interfere with the analysis312103109Almăşan, O.C., Hedeşiu, M., Băciuţ, G., Leucuţa, D.C., Băciuţ, M., Disk and joint morphology variations on coronal and sagittal MRI in temporomandibular joint disorders (2013) Clinical Oral Investigations, 17 (4), pp. 1243-1250. , http://dx.doi.org/10.1007/s00784-012-0803-4, PMid:22868824Brooks, S.L., Brand, J.W., Gibbs, S.J., Hollender, L., Lurie, A.G., Omnell, K.A., Westesson, P.L., White, S.C., Imaging of the temporomandibular joint: A position paper of the American Academy of Oral and Maxillofacial Radiology (1997) Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontics, 83 (5), pp. 609-618. , PMid:9159823Cozzollino, F.A., Rapoport, A., Franzi, A.S., Souza, R.P., Pereirta, C.A.B., Dedivitis, R.A., Correlação entre os achados clínicos e imaginológicos nas disfunções temporomandibulares (2008) Radiologia Brasileira, 41 (1), pp. 13-17. , http://dx.doi.org/10.1590/S0100-39842008000100006Larheim, T.A., Westesson, P., Sano, T., Temporomandibular joint disk displacement: Comparison in asymptomatic volunteers and patients (2001) Radiology, 218 (2), pp. 428-432. , http://dx.doi.org/10.1148/radiology.218.2.r01fe11428, PMid:11161157Lopes, S.L., Costa, A.L., Cruz, A.D., Li, L.M., Almeida, S.M., Clinical and MRI investigation of temporomandibular joint in major depressed patients (2012) Dento Maxillo Facial Radiology, 41 (4), pp. 316-322. , http://dx.doi.org/10.1259/dmfr/27328352, PMid:22517997 PMCid:PMC3729006Manfredini, D., Bonnini, S., Stellini, E., Salmaso, L., Guarda-Nardini, L., Comparison of magnetic resonance imaging findings in temporomandibular joints of the two sides (2014) Clinical Oral Investigations, 18 (2), pp. 499-506. , http://dx.doi.org/10.1007/s00784-013-0984-5, PMid:23640716Sano, T., Yamamoto, M., Okano, T., Gokan, T., Westesson, P.L., Commom abnormalities in temporomandibular joint imaging (2004) Current Problems in Diagnostic Radiology, 33 (1), pp. 16-24. , http://dx.doi.org/10.1016/j.cpradiol.2003.09.001, PMid:14712198Schiffman, E.L., Truelove, E.L., Ohrbach, R., Anderson, G.C., John, M.T., List, T., Look, J.O., The research diagnostic criteria for temporomandibular disorders. I: Overview and methodology for assessment of validity (2010) Journal of Orofacial Pain, 24 (1), pp. 7-24. , PMid:20213028 PMCid:PMC3157055Sessle, B.J., A focus on the research diagnostic criteria for temporomandibular disorders (2009) Journal of Orofacial Pain, 23 (1), pp. 5-6. , PMid:19264031Styles, C., Whyte, A., MRI in the assessment of internal derangement and pain within the temporomandibular joint: A pictorial essay (2002) British Journal of Oral & Maxillofacial Surgery, 40 (3), pp. 220-228. , http://dx.doi.org/10.1054/bjom.2001.0757, PMid:12054713Tasaki, M.M., Westesson, P.L., Isberg, A.M., Ren, Y.F., Tallents, R.H., Classification and prevalence of temporomandibular joint disc displacement in patients and symptom-free volunteers (1996) American Journal of Orthodontics and Dentofacial Orthopedics, 109 (3), pp. 249-262. , http://dx.doi.org/10.1016/S0889-5406(96)70148-8Tasali, N., Cubuk, R., Aricak, M., Ozarar, M., Saydam, B., Nur, H., Tuncbilek, N., Temporomandibular joint (TMJ) pain revisited with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) (2012) European Journal of Radiology, 81 (3), pp. 603-608. , http://dx.doi.org/10.1016/j.ejrad.2011.01.044, PMid:21300493Wangsrimongkol, T., Manosudprasit, M., Pisek, P., Chowchuen, P., Chantaramungkorn, M., Temporomandibular joint growth adaptation and articular disc positional changes in functional orthopedic treatment: Magnetic resonance imaging investigation (2012) Journal of the Medical Association of Thailand, 95, pp. S106-S115. , PMid:2396162

Modelos referentes ao padrão de variação temporal dos componentes de produtividade da cultura de feijão caracterizado por graus-dia .

Com o objetivo de caracterizar o padrão da variação de fitomassa seca de raízes, hastes, folhas e órgãos reprodutivos da cultura de feijão (Phaseolus vulgaris L.) em função do desenvolvimento relativo (ou número de graus-dia relativo) e de diferentes doses de nitrogênio, um experimento foi conduzido na área do Departamento de Produção Vegetal, Universidade de São Paulo, Piracicaba-SP, com a variedade cultivada lAC-Carioca Tybatá. Foi utilizado o delineamento inteiramente casualizado com quatro repetições e vinte e sete tratamentos, constituídos de combinações dos fatores doses de nitrogénio (O, 60 e 120 kg.ha) e épocas de avaliação (9 estádios/enológicos). Foram avaliados fitomassa seca de raízes (FSr), hastes (FSh), folhas (FSf), órgãos reprodutivos (FSor) e filomassa seca total (FST) em cada estádio fenológico. Foram ajustados dois tipos de modelo para cada órgão: um considerando a fitomassa seca absoluta e outro considerando a fitomassa seca relativa (relação entre o valor da fitomassa seca observada em cada época e o valor máximo observado de fitomassa seca), ambos em função do desenvolvimento relativo da cultura. Observou-se um padrão de variação sigmóide para FSor e FST. Para FSh e FSf, o padrão foi sigmóide até o ponto de máximo valor, com posterior declínio. Nas doses O e 120 kg.ha \' de N para FSr, o padrão foi semelhante ao da FSor e FST: na dose 60 kg.lia\', ocorreu declínio da fitomassa no final do ciclo. Concluiu-se que: (i) os modelos propostos são adequados para caracterizar a variação de fitomassa seca total, bem como, de raízes, hastes, folhas e órgãos reprodutivos durante o ciclo da cultura de feijão; (ii) o padrão de acúmulo de fitomassa seca, em termos absolutos, é influenciado pelas doses de N, porém, em termos relativos, é semelhante entre as doses de N para um mesmo órgão: e (iii) há relação entre fenologia e desenvolvimento relativo

Mitigating the effects of future climate on maize productivity.

Current climate changes affect agricultural production. Crop management strategies can be used to mitigate these effects. This study was carried out to evaluate the use of crop and soil management strategies to mitigate the effects of future climate on maize yield in mesoregions of the state of Minas Gerais, Brazil. The CSM-CERESMaize model was used to simulate the effect of maize root system depth and of the amount of plant residue left on the soil surface by the previous crop in maize yield for different scenarios of change in precipitation and solar radiation. The decrease in rainfall volume reduced the average maize yield in some regions by more than 50%. The increase in solar radiation maize yield rise, while its reduction caused more than 20% yield drop in most regions. The management strategies evaluated have the potential to mitigate such effects

A GEOMORFOLOGIA NO CONTEXTO DO PLANEJAMENTO AMBIENTAL: ESTUDO DO USO E OCUPAÇÃO DA SERRA BARRA DO VENTO – SERRINHA/BA

O uso e ocupação das terras em ambiente semiárido pode intensificar o aparecimento de processos de degradação ambiental. Objetiva-se Analisar a interação das características geomorfológicas com o uso e a ocupação das terras na Serra Barra do Vento, contribuindo para o planejamento ambiental, a partir do processamento de imagens orbitais e atividade de campo. Este estudo justifica-se pela necessidade de entender a contribuição da geomorfologia no uso/ocupação em ambiente semiárido

Double Exchange Model for Magnetic Hexaborides

A microscopic theory for rare-earth ferromagnetic hexaborides, such as Eu(1-x)Ca(x)B6, is proposed on the basis of the double-exchange Hamiltonian. In these systems, the reduced carrier concentrations place the Fermi level near the mobility edge, introduced in the spectral density by the disordered spin background. We show that the transport properties such as Hall effect, magnetoresitance, frequency dependent conductivity, and DC resistivity can be quantitatively described within the model. We also make specific predictions for the behavior of the Curie temperature, Tc, as a function of the plasma frequency, omega_p.Comment: 4 pages, 3 figure

Horizontal pressures in cylindrical metal silos and comparison with different international standards

The focus of this research was to evaluate the horizontal pressures on a cylindrical metal silo of corrugated walls and flat bottom with 1.82m diameter and 5.4m high, and to compare the values with those obtained theoretically by the ISO 11697, EP 433 and AS 3774 standards. The silo was symmetrically filled and constant speed with wheat cv. soft red for two different height/diameter ratios (H/D) and was unloaded through three orifices with a diameter of 71.6mm, one concentric and two eccentrics. Horizontal pressures were measured on the walls of the silo at three positions using hydraulic type pressure cells. The results showed that shortly after the start of the unloading, there was a mass flow above the quota of H/D = 1.2, whereas below this quota funnel flow occurred. It can be said that the EP 433 standard was more appropriate to predict horizontal pressures in silos in H/D ratio = 1.0, with eccentric unloading. For the H/D ratio = 1.5, AS 3774 standard was the one that produced values closer to the experimental

Sistema automatizado para monitoramento de parâmetros abióticos em tempo real e aplicações na Agricultura de Precisão.

Neste artigo é apresentado o desenvolvimento de um sistema automatizado para análise espaço-temporal de seqüências de parâmetros abióticos de curto termo com dados coletados em tempo real por uma rede de sensores fixos inteligentes. Esse sistema pode ser dividido basicamente em duas partes: uma base de dados e uma interface que oferece aos usuários a possibilidade de acesso remoto aos dados armazenados através da Internet, utilizando um navegador. O sistema possibilita a visualização desses dados na forma de relatórios e na forma gráfica. O trabalho foi dirigido para ser uma ferramenta de auxílio na tomada de decisões em agricultura de precisão. Uma das aplicações previstas é o controle da irrigação espacialmente diferenciada.bitstream/CNPDIA/8731/1/BPD05_2003.pd