1,426 research outputs found

    PARSEC PARAMETERIZATION METHODOLOGY FOR ENHANCING AIRFOILS GEOMETRY USING PSO ALGORITHM

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    The electromechanical generating system is mainly based on the characteristics wherein the turbine has to ”harvest” the energy of a working fluid. Thus, the engineering behind the blades, such as the geometry and construction, must be effectively consolidated to increase the overall turbine efficiency. This work aims to go further into the computational principles of modeling the turbine blades, precisely, the hydrokinetic turbine hydrofoil built by LEA (Engineering Laboratory and Environment - UNB). The study has a focus on designing and analyzing, through numerical studies of parameterization and optimization profiles, blades using computational tools such as MATLAB R2016b and XFOIL. In this case, the model study is part of the airfoil theory combined with the Particle Swarm Optimization technic (PSO), which are implemented to get a maximum utilization of the aerodynamic coefficient CL over CD of the blade. Furthermore, an optimal turbine blade geometry, set by PARSEC parameter, is found and compared with results obtained from the original hydrofoil, using the software of profile analysis XFOIL, to certify the mathematical method, proving its effectiveness to parameterize hydrodynamic profiles and optimize their geometries.Keywords: Hydrokinetic Turbine. Airfoils. Parameterization and Optimization. Parsec. PSO

    TRANSPORTE TRANSDÉRMICO DE NANOPARTÍCULAS METÁLICAS UTILIZANDO FONOFORESE: ESTUDOS ELETROQUÍMICOS

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    Existem diversos métodos de tratamento de doenças. Dentre eles, adesivos poliméricos contendo fármacos vêm sendo muito explorados por serem menos invasivos se comparados a outros métodos[1][2]. Nanopartículas de prata também são alvo de estudos devido a atividade antimicrobiana e cicatrizante que apresentam[3]. O trabalho teve como objetivo a avaliação da permeação de nanopartículas de prata através de uma membrana polimérica por meios eletroquímicos

    Herbicidas alachlor, pendimethalin e trifluralin na nodulação e crescimento inicial de plantas de amendoim

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    This work had the objective of evaluating the effect of the herbicides alachlor, pendimethalin and trifluralin on the initial growth of peanut plants (Arachis hypogaea L.) under greenhouse conditions for a period of thirty days as well as nodule number and dry weight for sixty days after the sowing period. The experiment was conducted at the Agronomy College of the Federal University ofBahia.The first experimental design was completely randomized with four treatments (control- rate zero; alachlor - 2.90 kg/ha, pendimethalin - 1.00 kg/haand trifluralin - 0.89 kg/ha) and three replieations. For each replication, plastie trays (70 em x 50 em x 10 em) were used with a yellow Latosol as the substrate and peanut seeds of the variety BRS 151-L 7 provided by EMBRAPA-CNPA. A seeond experiment was condueted with plastic pots of 5 kg, the same substrate, same treatments and experimental design with eight replieations. The following parameters were evaluated: seedling emergence, percentage of abnonnal seedlings and dead seeds, plant height, index of seedling emergenee velocity, root and shoot dry weight,number and dry weight of nodules. The results show that herbieides stimulate the initial nodulation of peanut plants, but reduce the pereentage of emergence, shoot dry weight and plant height. Therefore, the herbicides should be recommended with restrietions, for the studied eonditions. . Este trabalho teve como objetivos avaliar o efeito dos herbicidas alachlor, pendimethalin e trifluralin no crescimento inicial de plantas de amendoim (Arachis hypogaea L.) em casa de vegetação, por um período de trinta dias, e o número e massa seca dos nódulos após 60 dias do plantio. O experimento foi conduzido na casa de vegetação do Departamento de Química Agrícola e Solos da Escola de Agronomia da Uni versidade Federal da Bahia. O delineamento experimental do primeiro ensaio foi inteiramente casualizado, com quatro tratamentos e três repetições. Os tratamentos utilizados foram: alachlor (2,90 kg ha); pendimethalin (1,00 kg ha), trifluralin (0,89 kg ha) e testemunha. As parcelas foram constituidas de bandejas de plástico de 70 em x 50 em x 10 em, tendo como substrato um solo Latossolo amarelo álico coeso, utilizando-se sementes da variedade BRS 151- L7, oriundas da EMBRAPAlCNPA. No segundo ensaio, a unidade experimental constituiu-se de vasos plásticos de 5 kg com os mesmos tratamentos, substrato e delineamento experimental, com oito repetições. Avaliou-se os seguintes parâmetros: percentagem de emergência, plântulas anormais, sementes mortas, altura da planta, comprimento da raiz, índice de velocidade de emergência, massa seca da parte aérea e da raiz, número e massa seca de nódulos. Os herbicidas testados, apesar de estimularem a nodulação inicial das plantas de amendoim, reduzem a porcentagem de emergência, massa seca da parte aérea e altura das plantas, devendo ser recomendados com restrições nas condições estudadas.

    Análise da gestão de resíduos sólidos em conjuntos habitacionais do Programa ‘Minha Casa, Minha Vida’ na cidade de Salvador, Bahia, Brasil

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    Esse artigo analisa a aderência do gerenciamento de resíduos sólidos (GRS) em condomínios construídos por meio do Programa Minha Casa Minha Vida às diretrizes da Política Nacional de Resíduos Sólidos (PNRS). A investigação foi realizada em oito conjuntos habitacionais na cidade de Salvador/BA por meio de análise documental, visitas técnicas e realização de entrevistas. Os condomínios investigados apresentam condições favoráveis à implantação do GRS conforme preconizado na PNRS, porque estão sendo implantados em grande número, são organizados na forma de condomínios, agrupam pessoas com renda per capita semelhantes e possuem áreas que podem ser usadas para implantação de práticas de manejo sustentável de resíduos como a compostagem. No entanto, verificou-se a existência de condições inadequadas de manejo e/ou desvio de função do Abrigo de Resíduo (AR) existente. Portanto, conclui-se que não há aderência do GRS às premissas da PNRS nos condomínios estudados, apesar das condições favoráveis. </p

    Análise da gestão de resíduos sólidos em conjuntos habitacionais do Programa ‘Minha Casa, Minha Vida’ na cidade de Salvador, Bahia, Brasil

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    Esse artigo analisa a aderência do gerenciamento de resíduos sólidos (GRS) em condomínios construídos por meio do Programa Minha Casa Minha Vida às diretrizes da Política Nacional de Resíduos Sólidos (PNRS). A investigação foi realizada em oito conjuntos habitacionais na cidade de Salvador/BA por meio de análise documental, visitas técnicas e realização de entrevistas. Os condomínios investigados apresentam condições favoráveis à implantação do GRS conforme preconizado na PNRS, porque estão sendo implantados em grande número, são organizados na forma de condomínios, agrupam pessoas com renda per capita semelhantes e possuem áreas que podem ser usadas para implantação de práticas de manejo sustentável de resíduos como a compostagem. No entanto, verificou-se a existência de condições inadequadas de manejo e/ou desvio de função do Abrigo de Resíduo (AR) existente. Portanto, conclui-se que não há aderência do GRS às premissas da PNRS nos condomínios estudados, apesar das condições favoráveis.

    Linkage disequilibrium and population structure in wild and cultivated populations of rubber tree (Hevea brasiliensis).

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    Abstract: Among rubber tree species, which belong to the Hevea genus of the Euphorbiaceae family, Hevea brasiliensis (Willd. ex Adr.de Juss.) Muell. Arg. is the main commercial source of natural rubber production worldwide. Knowledge of the population structure and linkage disequilibrium (LD) of this species is essential for the efficient organization and exploitation of genetic resources. Here, we obtained single-nucleotide polymorphisms (SNPs) using a genotyping-by-sequencing (GBS) approach and then employed the SNPs for the following objectives: (i) to identify the positions of SNPs on a genetic map of a segregating mapping population, (ii) to evaluate the population structure of a germplasm collection, and (iii) to detect patterns of LD decay among chromosomes for future genetic association studies in rubber tree. A total of 626 genotypes, including both germplasm accessions (368) and individuals from a genetic mapping population (254), were genotyped. A total of 77,660 and 21,283 SNPs were detected by GBS in the germplasm and mapping populations, respectively. The mapping population, which was previously mapped, was constructed with 1,062 markers, among which only 576 SNPs came from GBS, reducing the average interval between two adjacent markers to 4.4 cM. SNPs from GBS genotyping were used for the analysis of genetic structure and LD estimation in the germplasm accessions. Two groups, which largely corresponded to the cultivated and wild populations, were detected using STRUCTURE and via principal coordinate analysis. LD analysis, also using the mapped SNPs, revealed that non-random associations varied along chromosomes, with regions of high LD interspersed with regions of low LD. Considering the length of the genetic map (4,693 cM) and the mean LD (0.49 for cultivated and 0.02 for wild populations), a large number of evenly spaced SNPs would be needed to perform genome-wide association studies in rubber tree, and the wilder the genotypes used, the more difficult the mapping saturation

    Disinhibition in Frontotemporal Dementia and Alzheimer's Disease:A Neuropsychological and Behavioural Investigation

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    OBJECTIVE: Cognitive tests of inhibitory control show variable results for the differential diagnosis between behavioural variant of Frontotemporal Dementia (bvFTD) and Alzheimer's disease (AD). We compared the diagnostic accuracies of tests of inhibitory control and of a behavioural questionnaire, to distinguish bvFTD from AD. METHODS: Three groups of participants were enrolled: 27 bvFTD patients, 25 AD patients, and 24 healthy controls. Groups were matched for gender, education, and socio-economic level. Participants underwent a comprehensive neuropsychological assessment of inhibitory control, including Hayling Test, Stroop, the Five Digits Test (FDT) and the Delay Discounting Task (DDT). Caregivers completed the Barratt Impulsiveness Scale 11th version (BIS-11). RESULTS: bvFTD and AD groups showed no difference in the tasks of inhibitory control, while the caregiver questionnaire revealed that bvFTD patients were significantly more impulsive (BIS-11: bvFTD 76.1+9.5, AD 62.9+13, p < .001). CONCLUSIONS: Neuropsychological tests of inhibitory control failed to distinguish bvFTD from AD. On the contrary, impulsivity caregiver-completed questionnaire provided good distinction between bvFTD and AD. These results highlight the current limits of cognitive measures of inhibitory control for the differential diagnosis between bvFTD and AD, whereas questionnaire information appears more reliable and in line with clinical diagnostics

    Discovery of 74 new bright ZZ Ceti stars in the first three years of TESS

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    We report the discovery of 74 new pulsating DA white dwarf stars, or ZZ Cetis, from the data obtained by the Transiting Exoplanet Survey Satellite mission, from Sectors 1 to 39, corresponding to the first 3 cycles. This includes objects from the Southern hemisphere (Sectors 1–13 and 27–39) and the Northern hemisphere (Sectors 14–26), observed with 120 s- and 20 s-cadence. Our sample likely includes 13 low-mass and one extremely low-mass white dwarf candidate, considering the mass determinations from fitting Gaia magnitudes and parallax. In addition, we present follow-up time series photometry from ground-based telescopes for 11 objects, which allowed us to detect a larger number of periods. For each object, we analysed the period spectra and performed an asteroseismological analysis, and we estimate the structure parameters of the sample, i.e. stellar mass, effective temperature, and hydrogen envelope mass. We estimate a mean asteroseismological mass of 〈Msis〉 = 0.635 ± 0.015 M⊙, excluding the candidate low or extremely low-mass objects. This value is in agreement with the mean mass using estimates from Gaia data, which is 〈Mphot〉 = 0.631 ± 0.040 M⊙, and with the mean mass of previously known ZZ Cetis of 〈M*〉 = 0.644 ± 0.034 M⊙. Our sample of 74 new bright ZZ Cetis increases the number of known ZZ Cetis by ∼20 per cent
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