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Evaluation of Impairment Caused by MPEG Video Frame Loss

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Engineering（科研） 2017年第5期9卷 493-503页

作者： Carlos Alexandre Gouvea da Silva guilherme Fernandes de Souza Miguel Joao guilherme Sauer Carlos Marcelo Pedroso Department of Electrical Engineering Federal University of ParanaCuritibaBrazil

This article presents a study on the impact of video frame losses on the quality perceived by users. Video compression standards, such as MPEG, use a sequence of frames called Group of Pictures (GOP), which is a video compression method which a frame is expressed in terms of one or more neighboring frames. This dependence between frames impacts directly in the quality because a loss of a reference frame prevents the decoding of other frames in GOP, thereby reducing the user-perceived quality. The assessment of quality in this article is estimated by Peak Signal Noise Ratio (PSNR), which compares the original and the received images. Computer simulations were used to show that the degradation on the quality may vary for different patterns of GOPs and type of lost frames.

关键词： MPEG-4 Video Streaming PSNR Frame Loss

Crohn's disease in one mixed-race population in Brazil

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World Journal of Gastroenterology 2007年第33期13卷 4489-4492页

作者： Genoile Oliveira Santana Luiz guilherme Costa Lyra Tamara Celi Almeida Santana Lidiane Bianca dos Reis Jorge Carvalho Guedes Maria Betania Toralles André Castro Lyra Gastrohepatology Unit Federal University of Bahia Brazil Gastrohepatology Unit Hospital San Rafael BahiaBrazil Gastrohepatology Unit Federal University of Bahia Brazil Department of Medicine Federal University of Bahia Brazil Gastrohepatology Unit Hospital San Rafael BahiaBrazil Department of Medicine Federal University of Bahia Brazil Gastrohepatology Unit Federal University of Bahia Brazil Department of Medicine Federal University of Bahia Brazil Genetic Unit Federal University of Bahia Brazil

AIM： To evaluate the classification and severity of Crohn＇s disease in different racial groups. METHODS： Patients with Crohn＇s disease from the outpatient clinic of the University Hospital Prof. Edgard Santos were enrolled in the study. This hospital is a reference centre for inflammatory bowel disease. Race was determined using self-identification. The Vienna＇s classification was applied for all subjects. The severity of Crohn＇s disease was determined according to the number of surgical procedures, hospital admissions in the last year and treatment with steroids and immunosuppressors. Statistical analysis was calculated using t test for means,χ^2 or F for proportions. A P value 〈 0.05 was considered to be significant. RESULTS： Sixty-five patients were enrolled. Non-white patients were more frequently diagnosed with Crohn＇s disease in the age less than 40 years than white patients. The behaviour of disease was similar in both groups with a high frequency of the penetrating form. There was a tendency for non-white patients to have a greater frequency of hospital admissions in the last year compared to white subjects. Non-whites also had a higher rate of colonic and upper gastrointestinal involvement, and were also more frequently on treatment with immunossupressors than white patients although this difference was not statistically significant. CONCLUSION： Non-white patients with Crohn＇s disease had an earlier diagnosis and appeared to have had a more severe disease Dresentation than white patients.

关键词： Racial group Brazil Race Inflammatory bowel disease Crohn's disease

Friction Analyses of Dimple-Structured Surface

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Journal of Mechanics Engineering and Automation 2016年第6期6卷 269-276页

作者： Rodrigo Lima Stoeterau Andreas Janssen guilherme Mallmann Deptartment of Mechatronic Engineering and Mechanical Systems Lab. of Surface Phenomenon University of S~o Paulo SaoPaulo 05508-970 Brazil Fraunhoffer Institute for Production Technology Aachen 52074 Germany

This paper proposes an investigation of the effects of laser engineering surface with dimple operating under lubrication. Dimples with semi-spherical geometry, with 100 μm in diameter and 25 μm in depth, were Laser-machined on the surfaces of high speed steel AISI H 13 discs, with three different distribution densities applied over the surface. Pin-on-disc experiments were performed by using counter bodies made with AISI 440C and Tungsten carbide ISO K20 pins. The experiments provided data information on the influence of dimple distribution on the coefficient of friction. Numerical simulations were performed to understand the influence of the pin and disc surface roughness on the contact problem. The results suggest that the design of dimple-structured surfaces rely on nine main parameters： material contact pair and its respective hardness, Young Modulus, the roughness of the surfaces, the dimple design, the dimple distribution, the load applied, the velocity and the type of lubricant. A better performance can be obtained from a compromise solution over these parameters, and the dimple concentration has a dominance over the other parameters. The best results were obtained with a lower concentration of dimples, under higher speed and load. Numerical simulations can also be used as a design tool, supporting decisions regarding shape and distribution of the dimples and material selections for the contact pair.

关键词： Structured surface dimples numeric simulation.

Applying Digital Image Processing to Evaluate a Extraction Method of Cartographic Features in Digital Images

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Journal of Earth Science and Engineering 2012年第4期2卷 241-246页

作者： Erivaldo Antonio da Silva guilherme Pina Cardim Cartography Department Faculty of Science and Technology Sao Paulo State University S6o Paulo 19060 900 Brazil Computer Science Department Faculty of Science and Technology Sao Paulo State University Sao Paulo 19060 900 Brazil

A topic studied in cartography is to make the extraction of cartographic features that provide the update of cartographic maps more easily. For this reason many automatic routines were created with the intent to perform the features extraction. Despite of all studies about this, some features cannot be found by the algorithm or it can extract some pixels unduly. So the current article aims to show the results with the software development that uses the original and reference image to calculate some statistics about the extraction process. Furthermore, the calculated statistics can be used to evaluate the extraction process.

关键词： Remote sensing cartographic features extraction evaluate process digital image processing.

The influence of porosity on tablet subdivision

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Particuology 2020年第6期18卷 192-196页

作者： Maira T.Teixeira Livia L.Sa-Barreto Izabel C.Silva Tais Gratieri guilherme M.Gelfuso Ricardo N.Marreto Mariana Landin Marcilio Cunha-Filho Laboratory of Food Drugs and Cosmetics(LTMAC)University of Brasilia(UnB)70910-900 BrasiliaDFBrazil Laboratory of Nanosystems and Drug Delivery Devices(NanoSYS) Federal University of GoiasGoianiaGO.Brazil Departamento de Farmacologia Farmacia y Tecnologia Farmaceutica1+D Farma Group(Gl-1645)Universidade de Santiago de CompostelaSpain

A tablet microstructure,especially the porosity,is a crucial parameter that influences the mechanical ***,tablet subdivisions were studied as a functi on of tablet *** tablets were manufactured in the presenee of different diluents,namely microcrystalline cellulose,LudipressR,or lactose ***,the add让ion of Camphor was investigated,which was thereafter sublimated with a view of obtaining tablets having varying degrees of *** assays were corre lated to the subdivision performs *** increase in porosity reduced the hardness and increased the tablet friability,adversely impacting the *** all the excipients,an increase in relative porosity>90%represented the threshold level from which an inadequate subdivision *** in crease in tablet porosity led to a reduction in mechanical resista nee,which,combined with a heterogeneous and disc on tinuous distribution of pores within the matrix,resulted in poor subdivision *** trolling tablet porosity is an important consideration when designing tablets having a subdivision purpose.

关键词： Tablet subdivision Porosity Mass variation Mass loss Friability Hardness

利用本地和侵入胎生鱼类（Poeciliidae,Teleostei）进行城市河流污染的综合生物学评估

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利用本地和侵入胎生鱼类（Poeciliidae,Teleostei）进行城市河流...

作者： guilherme Gomes Silva 西北农林科技大学

学位级别：硕士

外来入侵物种正在日益取代本地物种,尤其是在人为转化或污染的栖息地中。这为我们提供了使用入侵物种作为生物污染评估指标的可能性。然而,对于相同的焦点物种,综合生物学评估还依赖于多种方法的应用来量化它们对污染的生理或细胞遗传... 详细信息

外来入侵物种正在日益取代本地物种,尤其是在人为转化或污染的栖息地中。这为我们提供了使用入侵物种作为生物污染评估指标的可能性。然而,对于相同的焦点物种,综合生物学评估还依赖于多种方法的应用来量化它们对污染的生理或细胞遗传学反应。当物种被限制在受污染或未受污染的地点时,这是具有挑战性的。本研究利用一小组新热带胎生鱼类(胎鳉科)对水质进行综合生物学评估。通过比较巴西城市乌贝兰迪亚城市及郊区受到工业和生活废水不同程度污染的河流,证明了这个科的两个成员可以作为评估水污染水平的指标。在严重污染的地方,Phalloceros caudimacula tus似乎已被入侵孔雀鱼(Poecilia reticulata)所取代。尽管如此,本研究证明这两种物种都可以用于评估重金属(铅,铜和铬)的生物积累性。环境(沉积物)浓度预测了物种间体细胞组织中的浓度(R2值介于0.74和0.96之间)。此外,使用细胞遗传学方法估算了水污染的遗传毒性作用,并发现了污染水平(多个变量,压缩为主成分)用来预测物种间核异常的发生(例如,微核细胞的频率)R2在0.69和0.83之间)。在城市和受污染的环境中都会出现的胎鳉鱼,使这个科的鱼成为主要的生物监测和评估水质的焦点生物。两种物种可以互换使用,以评估水污染的遗传毒性影响,这可能有助于将来在广泛的地理范围内进行比较分析,因为胎鳉鱼科的成员已在世界范围内入侵了热带和亚热带地区。

关键词：生物积累遗传毒性 Poecilia Phalloceros 城市生态

Proximal sensor-enhanced soil mapping in complex soil-landscape areas of Brazil

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Pedosphere 2021年第4期31卷 615-626页

作者： Sérgio H.G.SILVA David C.WEINDORF Wilson M.FARIA Leandro C.PINTO Michele D.MENEZES Luiz R.G.guilherme Nilton CURI Department of Soil Science Federal University of LavrasLavras 37200-000(Brazil) Department of Earth and Atmospheric Sciences Central Michigan UniversityMount Pleasant 48858(USA)

Portable X-ray fluorescence(pXRF) spectrometry and magnetic susceptibility(MS) via magnetometer have been increasingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many countries with tropical soils. The objective of this study was to use proximal soil sensor data associated with terrain variables at varying spatial resolutions to predict soil classes using the Random Forest(RF) algorithm. The study was conducted on a 316-ha area featuring highly variable soil classes and complex soil-landscape relationships in Minas Gerais State, Brazil. The overall accuracy and Kappa index were evaluated using soils that were classified at 118 sites, with 90 being used for modeling and 28 for validation. Digital elevation models(DEMs) were created at 5-, 10-, 20-, and 30-m resolutions using contour lines from two sources. The resulting DEMs were processed to generate 12 terrain variables. Total Fe, Ti, and SiO_(2) contents were obtained using pXRF, with MS determined via a magnetometer. Soil class prediction was performed using the RF algorithm. The quality of the soil maps improved when using only the five most important covariates and combining proximal sensor data with terrain variables at different spatial resolutions. The finest spatial resolution did not always provide the most accurate maps. The high soil complexity in the area prevented highly accurate predictions. The most important variables influencing the soil mapping were MS, Fe, and Ti. Proximal sensor data associated with terrain information were successfully used to map Brazilian soils at variable spatial resolutions.

关键词： magnetic susceptibility magnetometer portable X-ray fluorescence spectrometer soil class soil spatial analysis spatial resolution terrain variables

Cerium alleviates drought-induced stress in Phaseolus vulgaris

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Journal of Rare Earths 2020年第3期38卷 324-331页

作者： Olívia Graziela Gelioli Salgado Jéssica Cristina Teodoro Joyce Pereira Alvarenga Cynthia de Oliveira Teotonio Soares de Carvalho Débora Domiciano Paulo Eduardo Ribeiro Marchiori Luiz Roberto Guimaraes guilherme Department of Soil Science Federal University of LavrasCP 3037Campus UFLALavras37200-000Brazil Department of Biology Federal University of LavrasCP 3037Campus UFLALavras37200-000Brazil

Extreme drought events are expected to be one of the main challenges for tropical agriculture and,consequently,for global food *** this reason,it is urgent to develop strategies to increase water use efficiency,as well as to increase crops’ ability to cope with *** rare earth elements(REEs) are known to alleviate damages in plants under abiotic stresses,we hypothesized that addition of Ce^3+to nutrient solution would promote the growth of common bean,especially under simulated drought *** test this hypothesis,we conducted an experiment evaluating the effect of six Ce^3+concentrations on the development and physiological traits of common bean grown in nutrient solution under normal condition and under induced drought stress,caused by the addition of polyethylene glycol6000 to the nutrient *** results show that Ce^3+alleviates water stress in common bean plants,increasing their survival rate and *** addition,Ce^3+application increases photosynthesis rate,chlorophyll content and water use efficiency under water ***,we observe no significant effect of Ce^3+on plants growing under normal ***,Ce3+seems to be a promising attenuator of drought stress for common bean.

关键词： Water stress Polyethylene glycol Rare earth elements Cerium nitrate Mitigation Common bean

Does landscape context affect pollinationrelated functional diversity and richness of understory flowers in forest fragments of Atlantic Rainforest in southeastern Brazil?

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Ecological Processes 2020年第1期9卷 737-748页

作者： Karoline Baptista de Lima Patrícia Alves Ferreira Milton Groppo Renato Goldenberg Emerson Ricardo Pansarin Roxana Cardoso Barreto guilherme Peres Coelho Yago Barros-Souza Danilo Boscolo Biology Department Faculty of PhilosophySciences and LettersUniversity of São PauloRibeirão PretoSP 14040-901Brazil National Institute of Science and Technology in Interdisciplinary and Transdisciplinary Studies in Ecology and Evolution(IN-TREE) SalvadorBrazil Botany Department Biological Science SectorParanáFederal UniversityCuritibaPR 81531-970Brazil Botany Department Biological Science CenterPernambuco Federal UniversityRecifePE 50670-420Brazil Institute of Bioscience Rio Grande do Sul Federal UniversityPorto AlegreRS 90040-060Brazil Botany Department Federal University of São CarlosSão CarlosSP 13565-905Brazil.

Background:How landscape modifications affect functional diversity of floral characteristics pertinent to pollinators is poorly *** possess functional traits that sometimes coevolved with pollinators,crucial for the maintenance of both pollinator and plant *** evaluated how richness and functional diversity of available understory flowers respond to forest cover and landscape heterogeneity in a multiscale *** in bloom were sampled from 25 landscapes in the understory of Atlantic Forest fragments in *** were classified into functional groups regarding flower characteristics relevant to *** heterogeneity and forest cover were measured in buffers ranging from 200 to 2000 m from sampling units and their correlation with plant richness and functional diversity was assessed using generalized linear models and further model selection through Akaike’s second-order information ***:Plants’richness and functional diversity were affected negatively by forest *** former responded to forest cover at a regional scale while the latter responded at a local *** landscape heterogeneity increased richness and functional ***:Our results showed that forest cover and landscape heterogeneity are important to support biodiversity related to pollination,mostly due to the availability of diversified resources and nesting sites associated to different land-uses for pollinators and flowering plant *** findings should highlight,along with forest cover,landscape heterogeneity as an environmental management priority in rural tropical areas for mitigating the loss of plant biodiversity and enhancing ecosystem functioning.

关键词： Functional diversity Pollination Landscape heterogeneity Forest cover Understory plant community