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Performance Improvement of Discrete-time Linear Control Systems Subject to Varying Sampling Rates Using the Tikhonov Regularization Method

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International Journal of Automation and computing 2020年第3期17卷 453-463页

作者： Fernando Agustin Pazos Anibal Zanini Amit Bhaya department of Electronics and Telecommunication Engineering State University of Rio de JaneiroRua São Fransciso Xavier 524Rio de Janeiro 20550-900Brazil Universidad de Buenos Aires-ITHES-UBA-CONICET Departamento de Ingenieria QuimicaPabellón de IndustriasCiudad UniversitariaBuenos Aires C1428EGAArgentina department of Electrical Engineering Federal University of Rio de JaneiroPEE/COPPE/UFRJRio de Janeiro 21945-970Brazil

Methods to stabilize discrete-time linear control systems subject to variable sampling rates,i.e.,using state feedback controllers,are well known in the *** recent works address the use of the Tikhonov regularization method,originally designed to attenuate the noise effects on ill-posed problems,with the aim of improving performance and stabilizing approximately controllable dynamical *** by these works,we propose the use of a feedback controller designed using the Tikhonov method to regularize discrete-time linear systems subject to varying sampling *** goal is to minimize an error function,thus improving the performance of the closed loop system and reducing the possibility of *** examples show the effectiveness of the proposed method.

关键词： Discrete-time switched systems Tikhonov regularization varying sampling rates discrete-time control systems networked control systems

dendritic spine density changes and homeostatic synaptic scaling:a meta-analysis of animal studies

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Neural Regeneration Research 2022年第1期17卷 20-24页

作者： Thiago C.Moulin Danielle Rayêe Helgi B.Schiöth Functional Pharmacology Unit Department of NeuroscienceUppsala UniversityUppsalaSweden Institute of Medical Biochemistry Federal University of Rio de JaneiroRio de JaneiroBrazil Institute of Biomedical Sciences Federal University of Rio de JaneiroRio de JaneiroBrazil department of Ophthalmology and Visual Sciences Albert Einstein College of MedicineNYUSA Institute for Translational Medicine and Biotechnology Sechenov First Moscow State Medical UniversityMoscowRussia

Mechanisms of homeostatic plasticity promote compensatory changes of cellular excitability in response to chronic changes in the network *** type of plasticity is essential for the maintenance of brain circuits and is involved in the regulation of neural regeneration and the progress of neurodegenerative *** of the most studied homeostatic processes is synaptic scaling,where global synaptic adjustments take place to restore the neuronal firing rate to a physiological range by the modulation of synaptic receptors,neurotransmitters,and ***,despite the comprehensive literature on the electrophysiological properties of homeostatic scaling,less is known about the structural adjustments that occur in the synapses and dendritic *** this study,we performed a meta-analysis of articles investigating the effects of chronic network excitation(synaptic downscaling)or inhibition(synaptic upscaling)on the dendritic spine density of *** results indicate that spine density is consistently reduced after protocols that induce synaptic scaling,independent of the intervention ***,we discuss the implication of our findings to the current knowledge on the morphological changes induced by homeostatic plasticity.

关键词： chronic inhibition chronic stimulation dendritic spines downscaling excitability homeostatic plasticity spine density synaptic scaling upscaling

Assessment of the demarcation Method for Federal Riverine and Accreted Lands: Case Study of the rio de janeiro state Section of the South Paraíba River

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Journal of Water Resource and Protection 2019年第11期11卷 1313-1326页

作者： Jussara Stutz Oliveira Mô nica de Aquino Galeano Massera da Hora Marcos Aurélio V. de Freitas Programa de Planejamento Energético da COPPE Rio de Janeiro Federal University Rio de Janeiro Brazil Environmental Water Resources Laboratory Department of Agricultural and Environmental Engineering Fluminense Federal University Niteroi Rio de Janeiro Brazil

This study analyzes the demarcation method of riverine and accreted land of the Brazilian Federal Heritage department and proposes the incorporation of the flow rate corresponding to the recurrence interval of two years, as recommended by the state Environmental Institute of the state of rio de janeiro. The case study of the rio de janeiro section of the Paraiba do Sul River was investigated, and the results indicate that the Federal Heritage department’s method does not consider the ongoing anthropization of the river, caused mainly by the construction and operation of hydroelectric plants. In addition, it was observed that the limnimetric scales of the studied gauging stations are influenced by constant changes in the riverbed and by riverbank occupation, making it difficult to estimate the ordinary flood level. The study concludes by suggesting the adoption of a flow rate with a recurrence interval of two years and the simulation of the runoff conditions for demarcation of the average ordinary flood line.

关键词： Federal Heritage department Limnimetric Scales Average Ordinary Flood Level

Correlation between Intestinal Health and Coccidiosis Prevalence in Broilers during Different Seasons of the Year in Brazil from 2012 to 2018

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Food and Nutrition Sciences 2024年第3期15卷 179-198页

作者： Fabio Luis Gazoni Gabriela Miotto Galli Marcel Manente Boiago Lenita Moura Stefani Aline Zampar Marco A. Juárez-Estrada Guillermo Tellez-Isaias Aleksandro S. da Silva Animal Health and Reproduction Veterinary Medicine Graduate Program Federal University of Santa Maria (UFSM) Santa Maria Brazil Animal Science Graduate Program Federal University of Rio Grande do Sul (UFRGS) Porto Alegre Brazil Animal Science Graduate Program Santa Catarina State University (UDESC) Chapecó Brazil departamento de Medicina y Zootecnia de Aves Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional Autonoma de Mexico Ciudad Universitaria Ciudad de Mexico Mexico department of Poultry Science Division of Agriculture University of Arkansas Fayetteville AR USA

Coccidiosis is a disease caused by intracellular protozoan parasites, specifically belonging to the genus Eimeria. These parasites target the gastrointestinal tract in different types of hosts, causing sores in the intestinal lining. The presence of these lesions reduces the animal’s ability to digest and absorb nutrients, significantly impacting their overall performance. The current study aimed to explore the potential correlation between seasonal variations and the incidence of Eimeria spp-induced lesions in broiler chickens’ gastrointestinal tracts in Brazil from 2012 to 2018. A total of 8,607 broiler chickens, aged 14 to 42 days, were sampled from 103 poultry integrated companies in Brazil to conduct intestinal health examinations. The sampling process involved selecting 3 to 6 chickens from each poultry house for examination. The assessment included various abnormalities such as shedding of intestinal cells and excessive fluid and mucus presence, thickening and tension of the intestines, food movement, roughened mucosal surface resembling a Turkish towel in the small intestine, tissue death, duodenal inflammation, intestinal inflammation, gizzard erosion, presence of worms and bedding material, and ingestion of mealworms. During the seasons, winter exhibited the highest average occurrence of Eimeria maxima microorganisms at 52.83%, with E. acervulina following closely at 26.42% in second place. In spring, E. maxima had an occurrence of 11.31%, while in fall, E. tenella had the lowest occurrence at 6.74%. When analyzing the seasonal occurrence of Eimeria, it was observed that E. maxima micro was more common during winter compared to summer (P = 0.0491). However, no discernible variation was observed in the occurrence of the remaining species across different seasons. Research findings suggest that subclinical coccidiosis is most prevalent during the winter season in Brazil. Likewise, clinical disease caused by E. acervulina is also prevalent during this time. I

关键词： Eimeria Epidemiology Intestinal Pathology Broiler Chickens Brazil

Experimental salt cavern in offshore ultra-deep water and well designevaluation for CO_(2) abatement

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International Journal of Mining Science and Technology 2019年第5期29卷 641-656页

作者： Alvaro Maia da Costa Pedro V.M.Costa Antonio C.O.Miranda Mariana B.R.Goulart Okhiria D.Udebhulu Nelson F.F.Ebecken Ricardo C.Azevedo Sérgio M.de Eston Giorgio de Tomi Andre B.Mendes Julio R.Meneghini Kazuo Nishimoto Claudio Mueller Sampaio Camila Brandao Alexandre Breda university of Sao Paulo(USP) Sao Paulo 01000-000Brazil Modecom-Technology in Geomechanics and Computing Modeling Rio de Janeiro 27570-000Brazil department of Civil and Environment Engineering University of Brasília(UnB)Brasília 70000-000Brazil COPPE Federal University of Rio de JaneiroRio de Janeiro 27570-000Brazil Technology Division of Shell Shell BrazilRio de Janeiro 27570-000Brazil

This paper presents a proposal for an experimental salt cavern in offshore ultra-deep water for CO2 abatement,including the instrumentation plan and well conceptual design evaluated for carbon capture and storage(CCS)*** studies are based on applied computational mechanics associated with field experimentation that has contributed to the technical feasibility of the underground potash mine at the state of Sergipe in *** knowhow allowed the stability analysis of several salt caverns for brine production at the state of Alagoas in Brazil and to the drilling through stratified thick layers of salt of the pre-salt reservoirs in Santos ***,this knowledge has been applied in the design of onshore and offshore salt caverns opened by dissolution for storage of natural gas and *** geomechanical study,through the application of computational mechanics,of offshore giant salt caverns of 450 m high by 150 m in diameter,shows that one cavern can store about 4 billion Sm3 or 7.2 million tons of *** the construction of the giant cavern,which will be the first gas storage offshore in the world,it has been decided to develop an experimental one,with smaller size,to obtained field *** experimental cavern will allow the calibration of parameters to be used in the structural integrity analysis of the cavern and well for storage of natural gas which is rich in CO2 under high pressure.

关键词： Salt cavern Pre-salt reservoir Geomechanical study Carbon capture and storage

The Colider and Roosevelt olcanic rocks (sw amazonian craton): geochemistry and sm-nd isotope characteristics of a silicic large igneous province

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Acta Geochimica 2021年第6期40卷 1023-1049页

作者： Bruna Saar de Almeida Mauro César Geraldes Carlos Augusto Sommer Felipe Corrales Antonio Joāo Paes de Barros Universidade do Estado do rio de janeiro Rio de JaneiroBrazil university of Geneva GenevaSwitzerland Universidade Federal do rio Grande do Sul Rio Grande do SulBrazil METAMAT(Mato Grosso state Geological Survey) CuiabaBrazil

The volcanic rocks of the Colíder and Roosevelt formations are extensively exposed in the south-central portion of the Amazonian Craton where effusive and pyroclastic rocks have been *** units,topped by chemical sediments and oceanic facies as rhyolite and andesite lavas,rhyodacite,and porphyritic dacite,with frequent intercalations of pyroclastic and epiclastic ***-rock geochemistry for 55 samples of rhyolitic to andesitic composition suggests the involvement of fertile mantle-derived components with E-MORB to OIB *** analyzed rocks display calc-alkaline to shoshonitic affinity consistent with generation related to an active continental *** whole-rock Sm-Nd isotope data from selected felsic volcanic rocks of the Colíder and Roosevelt formations yield negative initial eNd values between–3 and–9,indicating the predominantly crustal nature of the parental magmas with early Archean to late Paleoproterozoic(ca.2.5–2.0 Ga)depleted mantle model ages.

关键词： Amazonian craton Geochemistry Sm-Nd isotopes Paleoproterozoic Volcanism

Kinetic Rates of the Fischer Tropsch Synthesis on a Co/Nb_2O_5 Catalyst

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Journal of Natural Gas Chemistry 2006年第4期15卷 307-312页

作者： Víctor R.Ahón Paulo L.C.Lage Carlos D.D.de Souza Fabiana M.Mendes Martin Schmal Federal university of rio de janeiro Programa de Engenharia Química COPPE/UFRJ C.P.6850221941-972Rio de JaneiroRJBrazil

The kinetics of the Fischer-Tropsch reaction over a Co/Nb2O5 catalyst in a fixed bed reactor was investigated experimentally. Experiments were carried out under isothermal and isobaric conditions （T=543 K, P=2.1 MPa） and under different conditions of several H2/CO feed molar ratio （0.49-4.79）, space velocities （0.2-3.8 h^-1）, mass of catalyst （0.3-1.5 g）, and CO conversion （10%-29%）. Synthesis gas conversion was measured and data were reduced to estimate the kinetic parameters for different Langmuir-Hinshelwood rate expressions. Differential and integral reactor models were used for the nonlinear regression of kinetics parameters. One of the rate equations could well explain the data. The hydrocarbon product distributions that were experimentally determined exhibited an unusual behavior, and a possible explanation was discussed.

关键词： Fischer-Tropsch natural gas kinetics selectivity

Occurrence of Antimicrobials in River Water Samples from Rural Region of the state of rio de janeiro, Brazil

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Journal of Environmental Protection 2016年第2期7卷 230-241页

作者： Mychelle Alves Monteiro Bernardete Ferraz Spisso Julia Rodrigues Martins Pastor dos Santos Rafaela Pinto da Costa Rosana Gomes Ferreira Mararlene Ulberg Pereira Talita da Silva Miranda Bárbara Rodrigues Geraldino de Andrade Luiz Antonio d’Avila Chemistry School/Federal university of rio de janeiro (EQ/UFRJ) Rio de Janeiro Brazil National Institute for Quality Control in Health/Oswaldo Cruz Foundation (INCQS/FIOCRUZ) Rio de Janeiro Brazil university Centre of Barra Mansa (UBM) Barra Mansa Brazil National of Institute of Cancer (INCA) Rio de Janeiro Brazil

The occurrence of antimicrobials in the aquatic environment and drinking water has raised the question of their impact on the environment and public health. Animal production is one of the most expressive activities of Brazilian agribusiness. In order to ensure the productivity and competitiveness of the sector, the use of drugs for therapeutic and prophylactic purposes is a common practice. Due to the continuous release of antimicrobials into the environment, the aim of this study was to compare the frequency of detection of tetracyclines and sulfonamides in surface water collected from rural areas in Lidice District of rio Claro, in the state of rio de janeiro, Brazil. An investigative study was conducted with 24 river water samples analyzed by high-performance liquid chromatography coupled to tandem mass spectrometry and the aim of this study was to determine residues of sulfonamides and tetracyclines based on the USEPA method 1694. The results indicated the presence of sulfamethoxazole and oxytetracycline concentrations at the ng·L-1 level. The applied method showed overall good performance with recoveries above 57%, method detection limits ≤ 7.17 ng·L-1, method quantification limits ≤ 23.90 ng·L-1 and good linearity.

关键词： Antimicrobial LC-MS/MS Surface Water Sulfonamides Tetracyclines

Effects of a 12-Week Recreational Soccer Program on Resting Metabolic Rate Among Adolescents with Obesity

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Journal of Science in Sport and Exercise 2023年第3期5卷 218-225页

作者： Isabela F.Soares Felipe A.Cunha Fabrício Vasconcellos Graduate Program in Exercise Science and Sports University of Rio de Janeiro StateRio de JaneiroBrazil Laboratory of Physical Activity and Health Promotion Institute of Physical Education and SportsUniversity of Rio de Janeiro StateRua São Francisco Xavier 524/sala 8121F-MaracanãRio de JaneiroRJ CEP:20550-013Brazil

Objectives The purpose of this study was to investigate the chronic effects of a 12-week recreational soccer program(RSP)on resting metabolic rate(RMR)in adolescents with *** Eighteen adolescents with obesity were assigned to RSP[n=10,age=13.8±1.5 years,body mass index(BMI)=30.7±5 kg/m^(2)]and control(n=8,age=14.9±1.4 years,BMI=32.5±4.1 kg/m^(2))*** underwent anthropometric,body composition,cardiorespiratory fitness and RMR assessments at baseline and *** 12-week RSP consisted of small-sided games with 60-min performed 3 times per *** Post-intervention,between-group differences due to RSP emerged for body mass(Δ:−15.1 kg,P=0.043),BMI(Δ:−4.7 kg,P=0.05),waist and hip circumferences(Δ:−14.6 and−16.6 cm,P=0.015 and P=0.017,respectively),fat mass(Δ:−8.7 kg,P=0.049)and VO2max(Δ:5.5 mL/kg/min,P=0.013).No significant differences were detected for the absolute and adjusted RMR for fat mass and fat-free mass at baseline and after 12 weeks for both RSP and control groups,although a marked downward trend of 27.6%for adjusted RMR was observed post-control(1915 vs.1386 kcal/day;Δ:−529 kcal/day).Conclusion A 12-week RSP was effective for improving anthropometric,body composition and cardiorespiratory fitness health markers in adolescents with obesity,but not for RMR.

关键词： Basal metabolism Energy expenditure Calorimetry Exercise training Body mass