8,270 research outputs found
An investigation of genetic algorithm-based feature selection techniques applied to keystroke dynamics biometrics
Due to the continuous use of social networks, users can be vulnerable to online situations such as paedophilia treats. One of the ways to do the
investigation of an alleged pedophile is to verify the legitimacy of the genre that
it claims. One possible technique to adopt is keystroke dynamics analysis. However, this technique can extract many attributes, causing a negative impact on
the accuracy of the classifier due to the presence of redundant and irrelevant
attributes. Thus, this work using the wrapper approach in features selection using genetic algorithms and as KNN, SVM and Naive Bayes classifiers. Bringing
as best result the SVM classifier with 90% accuracy, identifying what is most
suitable for both bases
O DIREITO À SAÚDE E A JUDICIALIZAÇÃO: apontamentos sobre o acesso
RESUMO: O presente trabalho tem como objetivo apresentar com caráter exploratório, a ser desenvolvida no processo de doutoramento em Serviço Social, em curso no Programa de Pós-graduação em Serviço Social da Universidade do Estado do Rio de Janeiro. A proposta busca discorrer sobre como o acesso à saúde, no nível de alta complexidade do Sistema Único de Saúde, em uma instituição de tratamento de pacientes com câncer, tem sido vivenciado e enfrentado pela população, em um contexto de implantação de um Sistema Estadual de Regulação (SER) e quais são os entraves experimentados pela população que transladam para o Judiciário competências da esfera Executiva de poder. O cotidiano profissional revela nos momentos de atendimento ao paciente que ingressa por via judicial, que este muitas vezes se apresenta como último recurso para garantia do tratamento, trazendo à reflexão, ainda, questões concernentes aos direitos individual e coletivo à saúde
Flow of low viscosity Boger fluids through a microfluidic hyperbolic contraction
In this work we focus on the development of low viscosity Boger fluids and assess their elasticity analyzing the flow through a microfluidic hyperbolic contraction. Rheological tests in shear and extensional flows were carried out in order to evaluate the effect of the addition of a salt (NaCl) to dilute aqueous solutions of polyacrylamide at 400, 250, 125 and 50 ppm (w/w). The rheological data showed that when 1% (w/w) of NaCl was added, a significant decrease of the shear viscosity curve was observed, and a nearly constant shear viscosity was found for a wide range of shear rates, indicating Boger fluid behavior. The relaxation times, measured using a capillary break-up extensional rheometer (CaBER), decreased for lower polymer concentrations, and with the addition of NaCl. Visualizations of these Boger fluids flowing through a planar microfluidic geometry containing a hyperbolic contraction, which promotes a nearly uniform extension rate at the centerline of the geometry, was important to corroborate their degree of elasticity. Additionally, the quantification of the vortex growth upstream of the hyperbolic contraction was used with good accuracy and reproducibility to assess the relaxation time for the less concentrated Boger fluids, for which CaBER measurements are difficult to perform
Do procurement rules impact infrastructure investment efficiency ? an empirical analysis of inversao das fases in Sao Paulo state
As a means to reduce delays in public works implementation, a number of Brazilian states have recently reformed their procurement rules allowing contractor price proposals to be assessed before the technical evaluation of submitted bids is undertaken (in a procedure known as inversao das fases). In order to evaluate the effects of such reform, this paper adopts a difference-in-differences methodology to compare the procurement performance of Sao Paulo state (a reformer state) and Minas Gerais'(a non-reformer state) largest water and sewage utility along three efficiency dimensions: (i) procurement process duration; (ii) likelihood of complaint resolution litigation; and (iii) prices paid to contractors. The analysis finds that the reform is associated with a 24 day reduction in the duration of procurement processes for large projects and a 7 percentage point drop in the likelihood of court challenges irrespective of project size. Although both effects are economically important, only the latter is statistical significant. Finally, the paper finds no evidence of an effect of the procurement reform on prices paid.Government Procurement,E-Business,Public Sector Corruption&Anticorruption Measures,Contract Law,Investment and Investment Climate
Nanogel formation of polymer solutions flowing through porous media
A gelation process was seen to occur when Boger fluids made from aqueous solutions of polyacrylamide (PAA) and NaCl flowed through porous media with certain characteristics. As these viscoelastic fluids flow through a porous medium, the pressure drop across the bed varies linearly with the flow rate, as also happens with Newtonian fluids. Above a critical flow rate, elastic effects set in and the pressure drop grows above the low-flow-rate linear regime. Increasing further the flow rate, a more dramatic increase in the slope of the pressure drop curve can be observed as a consequence of nanogel formation. In this work, we discuss the reasons for this gelation process based on our measurements using porous media of different sizes, porosity and chemical composition. Additionally, the rheological properties of the fluids were investigated for shear and extensional flows. The fluids were also tested as they flowed through different microfluidic analogues of the porous media. The results indicate that the nanogel inception occurs with the adsorption of PAA molecules on the surface of the porous media particles that contain silica on their surfaces. Subsequently, if the interparticle space is small enough a jamming process occurs leading to flow-induced gel formation
The role of environmental awareness
Ferreira, L., Oliveira, T., & Neves, C. (2023). Consumer's intention to use and recommend smart home technologies: The role of environmental awareness. Energy, 263(Part C), 1-11. [125814]. https://doi.org/10.1016/j.energy.2022.125814 --- Funding: This work was supported by national funds through FCT (Fundação para a Ciência e a Tecnologia) under the project - UIDB/04152/2020 - Centro de Investigação em Gestão de Informação (MagIC).Environmental sustainability is gathering further importance in various fields, including our homes. Smart home technologies are increasingly contributing to more efficient energy consumption, but their adoption rate remains lower than expected. This study proposes a theoretical model based on the extended unified theory of acceptance and use of technology (UTAUT2) to explore the effects of environmental awareness on individual intentions and behaviour toward smart home technologies. Data collected from 255 individuals were used to test the research model. The findings provide meaningful insights for researchers, marketers, and policymakers, by highlighting newer environmental approaches to these technologies.publishersversionepub_ahead_of_prin
Carbonyl compounds in wine : factors related to presence and toxic effects
The objective of this study was to review technological and toxicological factors related to presence of carbonyl compounds found in wines, including acetaldehyde, formaldehyde, acrolein, ethyl carbamate (EC) and furfural. Acetaldehyde and formaldehyde may be formed through the ethanol and methanol oxidation, respectively. Acrolein may arise as a thermal degradation product of glycerol, amino acids, carbohydrates and triglycerides or by metabolic activity of microorganisms. In addition, acrolein and furfural are formed during wood combustion; therefore, these aldehydes may be present in raw materials due to the environmental contamination. Furfural is also a product of the Maillard reaction formed from sugars and amino acids, while ethyl carbamate occurs through the reaction between urea and ethanol. These compounds may react with SO2 and phenolic compounds to form non-volatile adducts, which positively modulates color stability, astringency and aroma in wine. However, when ingested through wine, electrophilic carbonyl compounds may form adducts with nucleophilic targets, such as DNA, resulting in genotoxicity along the gastrointestinal tract. Furthermore, carbonyl compounds induce the increase of reactive oxygen species and can trigger apoptosis, in addition to hepatocellular adenoma and carcinoma as a consequence of chronic hepatotoxicity. Neurodegenerative diseases may be related to the exposure to carbonyl compounds. Therefore, strategies to reduce the levels of these compounds should be studied in order to get the most out of the beneficial functional properties of wine consumption.O objetivo deste estudo foi revisar os fatores tecnológicos e toxicológicos relacionados à presença de compostos carbonílicos encontrados em vinhos, incluindo acetaldeído, formaldeído, acroleína, carbamato de etila (CE) e furfural. O acetaldeído e o formaldeído podem ser formados através da oxidação do etanol e do metanol, respectivamente. A acroleína pode surgir como um produto de degradação térmica de glicerol, aminoácidos, carboidratos e triglicerídeos ou pela atividade metabólica de microorganismos. Além disso, a acroleína e o furfural são formados durante a combustão da madeira. Portanto, esses aldeídos podem estar presentes nas matérias-primas devido à contaminação ambiental. O furfural é também um produto da reação de Maillard formado a partir de açúcares e aminoácidos, enquanto o carbamato de etila ocorre através da reação entre uréia e etanol. Estes compostos podem reagir com SO2 e compostos fenólicos para formar adutos não voláteis, que modulam positivamente a estabilidade da cor, adstringência e aroma no vinho. No entanto, quando ingeridos através do vinho, os compostos carbonílicos que são eletrofílicos podem formar adutos com alvos nucleofílicos, como o DNA, resultando em genotoxicidade ao longo do trato gastrintestinal. Além disso, os compostos carbonílicos também induzem o aumento de espécies reativas de oxigênio e podem desencadear a apoptose, além de adenoma e carcinoma hepatocelular como consequência da hepatotoxicidade crônica. Doenças neurodegenerativas podem estar relacionadas à exposição aos compostos carbonílicos. Com isso, estratégias para reduzir os níveis desses compostos devem ser estudadas para obter o máximo das propriedades funcionais benéficas do consumo de vinho
Ciclo de Debates: La Geopolítica de las Crisis, Conflictos y Procesos de Integración Regional.
El presente proyecto de extensión tiene por objetivo dar a conocer a la
comunidad académica y externa conocimientos básicos sobre las principales
crisis políticas, económicas y sociales, llevando en consideración las
geopolíticas de las principales guerras, conflicto, procesos de cooperación y de
integración regional que se desarrollan en el escenario internacional y regional
latinoamericano. Incentivando al debate de temas contemporáneos de filosofía
política, geopolítica, política y estrategia a partir de la exhibición de videos,
presentación de Slide con explicaciones didácticas por parte de docentes,
discentes y miembros del equipo del NEEGI (Núcleo de Estudios Estratégicos
Geopolítica e Integración Regional) y sus diversos observatorios. Además, son
debatidos temas contemporáneos de la política Nacional e Internacional, como
la crisis petrolífera y energética, el papel de los medios de comunicación en la
política, la cuestión de género y las relaciones sociales de poder, las crisis
políticas en América Latina y el papel de los países emergentes en la
gobernanza global. Se analizan las principales causas y consecuencias de las
grandes crisis, el papel y la influencia de las principales crisis políticas,
económicas y sociales contemporáneas. La metodología que se utiliza es
través del planeamiento y la organización de minicursos que son divulgados
por las diferentes redes sociales (Facebook, Instagram y blog), así como
carteles divulgando las diferentes temáticas presentadas. También se
procederá al apoyo y realización de eventos, palestras y debates relacionados
a las principales temáticas abordadas por el presente proyecto. En cuanto a los
resultados que se pretende alcanzar con la acción de extensión es de contribuir
para el debate y la difusión de conocimientos sobre la Política Internacional
contemporánea, con la finalidad de generar conciencia que nos permita pensar
en ideas para futuros proyectos estratégicos que nos ayuden a enfrentar o
apaciguar diversas realidades que enfrentamos en la actualidad
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