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Phenomenological model for torsional galloping of an elastic flat plate due to hydrodynamic loads

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Journal of Hydrodynamics 2014年第1期26卷 57-65页

作者： fernandes antonio carlos ARMANDEI Mohammadmehdi Department of Naval and Ocean Engineering COPPE/UFRJ

This study investigates the torsional galloping phenomenon, an instability type flow-induced oscillation, in an elastic stru-cture due to hydrodynamic loads into the water current. The structure applied here is a rectangular flat plate with an elastic axis in its mid-chord length. The elasticity is provided by torsion spring. The flat plate has only one degree of freedom which is rotation in pure yaw about its axis. It is observed that as the current speed is higher than a critical velocity, the flat plate becomes unstable. The instability leads to torsional galloping occurrence, as a result of which the flat plate begins to yaw about the elastic axis. By testing two different chord lengths each with several torsion spring rates, the flat plate behavior is investigated and three different responses are recognized. Then, a phenomenological model is developed with the original kernel in the form of the van der Pol-Duffing equa-tion. The model explains these three responses observed experimentally.

关键词： torsional galloping flow-induced oscillation phenomenological model van der Pol-Duffing equation

Stability analysis of the fluttering and autorotation of flow-induced rotation of a hinged flat plate

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Journal of Hydrodynamics 2013年第5期25卷 755-762页

作者： MIRZAEISEFAT Sina fernandes antonio carlos Department of Naval Architecture and Marine Engineering University of Michigan COPPE/UFRJ Federal University of Rio de Janeiro

This work describes investigations performed on the interaction of uniform current and freely rotating plate about a fixed vertical axis. Fluttering and autorotation are two different motions that may occur during the flow induced rotation. The dimensional analysis proves that the motion in flow induced rotation motion is governed essentially by the dimensionless moment of inertia and Reynolds number. Certain combinations define the stability boundaries between fluttering and autorotation. Fluttering is oscillation of body about a vertical axis and the autorotation is a name given to the case when the body turns continuously about the vertical axis First, the loads and moment coefficients are calculated by experiments and streamline theory for different angles of attack for a fixed fiat plate. Then for dynamic case, a bifurcation diagram is presented based on experiments to classify different motion states of flow induced rotation. Finally, a dynamical model is proposed for stability analysis of flow induced rotation of a flat plate.

关键词： flow-induced rotation autorotation fluttering stability analysis

Effect of Noisy Fitness in Real-Time Strategy Games Player Behaviour Optimisation Using Evolutionary Algorithms

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Journal of Computer Science & Technology 2012年第5期27卷 1007-1023页

作者： antonio M. Mora antonio Fernndez-Ares Juan J. Merelo Pablo García-Snchez carlos M. fernandes Computer Architecture and Technology Department University of Granada Institute for Systems and Robotics Technical University of Lisbon

This paper investigates the performance and the results of an evolutionary algorithm （EA） specifically designed for evolving the decision engine of a program （which, in this context, is called bot） that plays Planet Wars. This game, which was chosen for the Google Artificial Intelligence Challenge in 2010, requires the bot to deal with multiple target planets, while achieving a certain degree of adaptability in order to defeat different opponents in different scenarios. The decision engine of the bot is initially based on a set of rules that have been defined after an empirical study, and a genetic algorithm （GA） is used for tuning the set of constants, weights and probabilities that those rules include, and therefore, the general behaviour of the bot. Then, the bot is supplied with the evolved decision engine and the results obtained when competing with other bots （a bot offered by Google as a sparring partner, and a scripted bot with a pre-established behaviour） are thoroughly analysed. The evaluation of the candidate solutions is based on the result of non-deterministic battles （and environmental interactions） against other bots, whose outcome depends on random draws as well as on the opponents＇ actions. Therefore, the proposed GA is dealing with a noisy fitness function. After analysing the effects of the noisy fitness, we conclude that tackling randomness via repeated combats and reevaluations reduces this effect and makes the GA a highly valuable approach for solving this problem.

关键词： real-time strategy game genetic algorithm noisy fitness player behaviour optimisation parameter adaptation

Structural and functional differences in the brains of patients with MCI with and without depressive symptoms and their relations with Alzheimer's disease:an MRI study

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Psychoradiology 2023年第1期3卷 182-192页

作者： Rodolfo Dias Chiari-Correia Vitor Tumas antonio carlos santos carlos Emesto G Salmon Department of Neurosciences and Behavioral Sciences Ribeirao Preto Medical SchoolUniversity of Sao Paulo3900 Bandeirantes AvenueRibeirao Preto SP14040-900Brazil Department of Medical Imaging Hematology and Clinical OncologyRibeirao Preto Medical SchoolUniversity of Sao Paulo3900 Bandeirantes AvenueRibeirao Preto SP14040-900Brazil Department of Physics Faculty of PhilosophySciences and LettersUniversity of Sao Paulo3900 Bandeirantes AvenueRibeirao Preto SP14040-900Brazil

Background:The mild cognitive impairment(MCI)stage among elderly individuals is very complex,and the level of diagnostic accu-racy is far from *** studies have tried to improve the’MCI due to Alzheimer’s disease(AD)’classification by further stratifying these patients into ***-related symptoms may play an important role in helping to better define the MCI stage in elderly ***:In this work,we explored functional and structural differences in the brains of patients with nondepressed MCI(nDMCI)and patients with MCI with depressive symptoms(DMCI),and we examined how these groups relate to AD atrophy patterns and cognitive ***:Sixty-five participants underwent MRI exams and were divided into four groups:cognitively normal,nDMCI,DMCI,and *** compared the regional brain volumes,cortical thickness,and white matter microstructure measures using diffusion tensor imaging among ***,we evaluated changes in functional connectivity using fMRI ***:In comparison to the nDMCI group,the DMCI patients had more pronounced atrophy in the hippocampus and ***,DMCI patients had asymmetric damage in the limbic-frontal white matter ***,two medial pos-terior regions,the isthmus of cingulate gyrus and especially the lingual gyrus,had high importance in the structural and functional differentiation between the two ***:It is possible to differentiate nDMCI from DMCI patients using MRI techniques,which may contribute to a better charac-terization of subtypes of the MCI stage.

关键词： mild cognitive impairment depressive disorders Alzheimer’s Disease neuroimaging

Towards an integrated risk analysis security framework according to a systematic analysis of existing proposals

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Frontiers of Computer Science 2024年第3期18卷 199-216页

作者： antonio santos-OLMO Luis Enrique SÁNCHEZ David G.ROSADO Manuel A.SERRANO carlos BLANCO Haralambos MOURATIDIS Eduardo FERNÁNDEZ-MEDINA GSyA Research Group University of Castilla-La ManchaCiudad Real 13071Spain Institute for Analytics and Data Science University of EssexColchester CO43SQUK Alarcos Research Group University of Castilla-La ManchaCiudad Real 13071Spain ISTR Research group Department of Computer Science and ElectronicsUniversity of CantabriaSantander 39005Spain

The information society depends increasingly on risk assessment and management systems as means to adequately protect its key information *** availability of these systems is now vital for the protection and evolution of ***,several factors have led to an increasing need for more accurate risk analysis *** are:the speed at which technologies evolve,their global impact and the growing requirement for companies to *** analysis processes must consequently adapt to these new circumstances and new technological *** objective of this paper is,therefore,to present the results of an exhaustive analysis of the techniques and methods offered by the scientific community with the aim of identifying their main weaknesses and providing a new risk assessment and management *** analysis was carried out using the systematic review protocol and found that these proposals do not fully meet these new *** paper also presents a summary of MARISMA,the risk analysis and management framework designed by our research *** basis of our framework is the main existing risk standards and proposals,and it seeks to address the weaknesses found in these *** is in a process of continuous improvement,as is being applied by customers in several European and American *** consists of a risk data management module,a methodology for its systematic application and a tool that automates the process.

关键词： information security management security system security risk assessment and management

Prevalence and risk factors for acquired long QT syndrome in the emergency department:a retrospective observational study

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World Journal of Emergency Medicine 2023年第6期14卷 454-461页

作者： Diogo de Almeida fernandes Guilherme de Freitas Camoes Diana Ferreira Carolina Queijo carlos Fontes-Ribeiro Lino Gongalves Rui Pina Natalia antonio Department of Cardiology Coimbra Hospital and University Centre(CHUC)Coimbra 3000-075Portugal Department of Internal Medicine Coimbra Hospital and University Centre(CHUC)Coimbra 3000-075Portugal Faculty of Medicine University of CoimbraCoimbra 3000-370Portugal Institute for Clinical and Biomedical Research Faculty of MedicineUniversity of CoimbraCoimbra 3000-548Portugal

BACKGROUND: Long QT syndrome(LQTS) is a heterogeneous syndrome that may be congenital or, more frequently, acquired. The real-world prevalence of acquired LQTS(aLQTS) in the emergency department(ED) remains to be determined. The aim of this study was to determine prevalence of aLQTS and its impact on symptoms on ED ***: Electrocardiograms(ECG) of 5,056 consecutively patients admitted in the ED of a tertiary hospital between January 28th and March 17th of 2020 were reviewed. All patients with aLQTS were included. Clinical data with a focus on QT prolonging drugs and clinical factors were recorded. Statistical comparison was made between the groups with and without corrected QT(QTc) interval greater than 500 ms(value that is considered severely increased).RESULTS: A total of 383 ECGs with prolonged QTc were recognized, corresponding to a prevalence of aLQTS at admission of 7.82%. Patients with aLQTS were more commonly men(53.3%) with an age of(73.49±14.79) years old and QTc interval of(505.3±32.4) ms. Only 20.4% of these patients with aLQTS were symptomatic. No ventricular arrhythmias were recorded. Patients with QT interval greater than 500 ms were more frequently female(59.5%;P<0.001) and were more frequently on QT prolonging drugs(77.3%;P=0.025). Main contributing factor was intake of antibiotics(odds ratio [OR] 4.680) followed by female gender(OR 2.473) and intake of antipsychotics(OR 1.925).CONCLUSION: aLQTS is particularly prevalent in the ED. Female patients on antibiotics and antipsychotics are at particularly high risk. Efforts must be made to avoid, detect and treat aLQTS as early as possible.

关键词： Long QT syndrome Epidemiology Drug interactions Emergency department

Redemocratization,Social Movements and the Urban Protection of Rio de Janeiro

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Journal of Civil Engineering and Architecture 2018年第10期12卷 694-705页

作者： Claudio antonio santos Lima carlos Federal Rural University of Rio de Janeiro(UFRRJ) Seropédica23.897-000Brazil

The main goal of this article is to evaluate critically the urban protection bias in the legislative context of Rio de Janeiro,since the 1980s,when the redemocratization of the country took place,until the 2000s,marked by major sporting events and the distinction of a part of the city site as“cultural landscape of humanity”,granted by UNESCO(2012).During this period,new legal provisions for environmental protection appeared in Rio de Janeiro’s legislation,especially the instrument called the Cultural Environment Protection Area(APAC in Portuguese),which constituted a counterpoint to previous urban policies,characterized by urban plans that invariably proposed urban renewal,with a view to the adaptation of the city to the demands of the property and car industries *** aim here is to evaluate the use of the urban protection tool by the city hall and its distribution through the city site,identifying the different motivations that originated the urban protection initiatives,as well as respective political-administrative impacts.

关键词： Urban planning conservation areas cultural heritage

Inositol 1,4,5-trisphosphate receptor in the liver:Expression and function

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World Journal of Gastroenterology 2019年第44期25卷 6483-6494页

作者： Fernanda de Oliveira Lemos Rodrigo M Florentino antonio carlos Melo Lima Filho Marcone Loiola dos santos M Fatima Leite Department of Physiology and Biophysics Universidade Federal de Minas GeraisBelo HorizonteMinas Gerais 31270-901Brazil Department of Cell Biology Universidade Federal de Minas GeraisBelo HorizonteMinas Gerais 31270-901Brazil

The liver is a complex organ that performs several functions to maintain *** functions are modulated by calcium,a second messenger that regulates several intracellular *** hepatocytes and cholangiocytes,which are the epithelial cell types in the liver,inositol 1,4,5-trisphosphate(InsP3)receptors(ITPR)are the only intracellular calcium release *** isoforms of the ITPR have been described,named type 1,type 2 and type *** ITPR isoforms are differentially expressed in liver cells where they regulate distinct physiological *** in the expression level of these receptors correlate with several liver diseases and hepatic *** this review,we highlight how the expression level,modulation,and localization of ITPR isoforms in hepatocytes and cholangiocytes play a role in hepatic homeostasis and liver pathology.

关键词： Inositol 1,4,5-trisphosphate receptor Liver Calcium signaling Hepatocytes and cholangiocytes

Stochastic seismic inversion and Bayesian facies classification applied to porosity modeling and igneous rock identification

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Petroleum Science 2024年第2期21卷 918-935页

作者： Fábio Júnior Damasceno fernandes Leonardo Teixeira antonio Fernando Menezes Freire Wagner Moreira Lupinacci Exploratory Interpretation and Reservoir Characterization Group(GIECAR) Department of Geology and GeophysicsFederal Fluminense UniversityNiter oiRJ24210-346Brazil Petrobras Rio de JaneiroRJ20231-030Brazil National Institute of Science and Technology of Petroleum Geophysics(INCT-GP/CNPQ) Niter oiRJ24210-346Brazil

We apply stochastic seismic inversion and Bayesian facies classification for porosity modeling and igneous rock identification in the presalt interval of the santos Basin. This integration of seismic and well-derived information enhances reservoir characterization. Stochastic inversion and Bayesian classification are powerful tools because they permit addressing the uncertainties in the model. We used the ES-MDA algorithm to achieve the realizations equivalent to the percentiles P10, P50, and P90 of acoustic impedance, a novel method for acoustic inversion in presalt. The facies were divided into five: reservoir 1,reservoir 2, tight carbonates, clayey rocks, and igneous rocks. To deal with the overlaps in acoustic impedance values of facies, we included geological information using a priori probability, indicating that structural highs are reservoir-dominated. To illustrate our approach, we conducted porosity modeling using facies-related rock-physics models for rock-physics inversion in an area with a well drilled in a coquina bank and evaluated the thickness and extension of an igneous intrusion near the carbonate-salt interface. The modeled porosity and the classified seismic facies are in good agreement with the ones observed in the wells. Notably, the coquinas bank presents an improvement in the porosity towards the top. The a priori probability model was crucial for limiting the clayey rocks to the structural lows. In Well B, the hit rate of the igneous rock in the three scenarios is higher than 60%, showing an excellent thickness-prediction capability.

关键词： Stochastic inversion Bayesian classification Porosity modeling Carbonate reservoirs Igneous rocks