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A phased approach to enable hybrid simulation of complex structures

Earthquake Engineering and Engineering Vibration 2014年第S1期13卷 63-77页

作者： Billie f.Spencer Jr. Chia-Ming Chang Thomas M.frankie Daniel A.Kuchma pedro f.silva Adel E.Abdelnaby Department of Civil Engineering University of Illinois at Urbana-Champaign Nathan M.& Anne M.Newmark Endowed Chair Earthquake Engineering Research &Test Center Guangzhou University Associate Professor Wiss JanneyElstner AssociatesInc. Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign Department of Civil and Environmental Engineering George Washington University Department of Civil Engineering University of Memphis Assistant Professor

Hybrid simulation has been shown to be a cost-effective approach for assessing the seismic performance of structures. In hybrid simulation,critical parts of a structure are physically tested,while the remaining portions of the system are concurrently simulated computationally,typically using a finite element model. This combination is realized through a numerical time-integration scheme,which allows for investigation of full system-level responses of a structure in a cost-effective manner. However,conducting hybrid simulation of complex structures within large-scale testing facilities presents significant challenges. for example,the chosen modeling scheme may create numerical inaccuracies or even result in unstable simulations; the displacement and force capacity of the experimental system can be exceeded; and a hybrid test may be terminated due to poor communication between modules(e.g.,loading controllers,data acquisition systems,simulation coordinator). These problems can cause the simulation to stop suddenly,and in some cases can even result in damage to the experimental specimens; the end result can be failure of the entire experiment. This study proposes a phased approach to hybrid simulation that can validate all of the hybrid simulation components and ensure the integrity largescale hybrid simulation. In this approach,a series of hybrid simulations employing numerical components and small-scale experimental components are examined to establish this preparedness for the large-scale experiment. This validation program is incorporated into an existing,mature hybrid simulation framework,which is currently utilized in the Multi-Axial full-Scale Sub-Structuring Testing and Simulation(MUST-SIM) facility of the George E. Brown Network for Earthquake Engineering Simulation(NEES) equipment site at the University of Illinois at Urbana-Champaign. A hybrid simulation of a four-span curved bridge is presented as an example,in which three piers are experimentally controlle

关键词： hybrid simulation seismic performance evaluation phased approach curved bridge MUST-SIM facility

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Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking

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Defence Technology（防务技术） 2024年第7期37卷 62-68页

作者： Luís Quinto pedro Pinheiro Sergio B.Goncalves Ivo Roupa Paula Simoes Miguel Tavares da silva CINAMIL Academia MilitarInstituto Universitario MilitarLisbonPortugal IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational *** exoskeletons have been developed recently to address these challenges,presenting various limitations that affect their operational or everyday *** article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metabolic costs during walking,seeking to identify a force element that could be applied to the target *** on the 6-min walk test,twenty-nine subjects participated in the study using three different force *** results indicate that it is possible to reduce metabolic expenditure while using the developed ***,the comfort and range of motion results verify the exoskeleton's suitability for use in uneven terrain and during extended ***,the choice of the force element should be tailored to each user,and the control system should be adjustable to optimise the exoskeleton's performance.

关键词： Ankle passive exoskeleton Metabolic cost reduction Dual-use exoskeleton Gait Biomechanics

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Determination of critical state line(CSL)for silty-sandy iron ore tailings subjected to low-high confining pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1684-1695页

作者： Nilo Cesar Consoli João Vítor de Azambuja Carvalho Alexia Cindy Wagner Hugo Carlos Scheuermann filho Inácio Carvalho pedro Pazzoto Cacciari João Paulo de Sousa silva Civil Engineering Universidade Federal do Rio Grande do SulPorto AlegreRS90035-190Brazil Exploration and Mineral Projects-Mineral Development Centre VALE S.A.Santa LuziaMG33040-900Brazil Department of Civil Geological and Mining EngineeringPolytechnique MontrealQuebecH3C 3A7Canada

The disposal of filtered tailings in high dry stacks can induce particle breakage,changing the material's behaviour during the structure's *** grading changes influence material properties at the critical state,and this is not mature for intermediate artificial soils(tailings)in a broad range of confining *** this paper,it aims to describe the behaviour of iron ore tailings in a spectrum of confining pressures broader than the reported in previous studies.A series of consolidated drained(CD)triaxial tests was carried out with confining pressures ranging from 0.075 MPa to 120 *** results show that the amount of breakage plays an essential role in the response of iron ore *** existence of curved critical state line(CSL)in both specific volume(ν)-logarithm of mean effective stress(p′)and deviatoric stress(q)-mean effective stress(p′)planes,and different responses in the deviatoric stress-axial strain-volumetric strain curves were *** inverse S-shaped equation was proposed to represent the silty-sandy tailings'behaviour up to high pressures onν-lnp′*** proposed equation provides a basis for enhancing constitutive models and considers the evolution of the grading up to severe loading *** adjustment considered three regions with different responses associated with particle breakage at different pressure levels.

关键词： Tailings Iron ore tailings dry stacking Silty-sandy material Critical state soil mechanics High confining pressures Particle breakage

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Comparison of Surgical Techniques Used in Treating Acromioclavicular Dislocation in Patients Participating in Sports: A Systematic Review

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Open Journal of Orthopedics 2024年第1期14卷 41-52页

作者： Walter Hugo Brandão Nascimento Paulo Renan Matos Sucupira Cunha João pedro Pimentel Abreu Lethycia Pereira Rosa Kamilly Iêda silva Veigas Rodrigo Martins silva Caetano Orthopedic and Trauma Surgeon Brazilian Army Rio de Janeiro Brazil Orthopedic and Trauma Surgeon S&atildeo Luís Brazil Scholarship Holder National Council for Scientific and Technological Development (CNPq) S&atildeo Luís Brazil School of Medicine Federal University of Maranh&atildeo (UFMA) S&atildeo Luís Brazil Orthopedic and Trauma Surgeon Shoulder and Elbow Surgery Specialist University Hospital of the Federal University of Maranh&atildeo (HUUFMA/EBSERH) S&atildeo Luís Brazil

Introduction: The acromioclavicular joint is a superficial diarthrodial joint that surrounds the medial articular facet of the acromion and the distal portion of the clavicle. Due to its anatomy and biomechanics, it is highly susceptible to trauma and in young men who play contact sports, acromioclavicular dislocation is common. This article aimed to systematically review the literature and compare the surgical techniques used in the treatment of acromioclavicular dislocation in patients who practice sports. Methods: This systematic review was conducted according to the International Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Eligible studies for this systematic review included articles in English or Spanish published between 2013 and 2023, which mention the occurrence of acromioclavicular dislocation during sports practices. Additionally, only studies that addressed the surgical treatment of acromion-clavicular dislocation and contained original data on the topic were included. Results: We found 144 eligible studies after searching the LILACS and PubMed databases. Based on the inclusion and exclusion criteria and the reviewers’ consensus, we selected four studies for the systematic review. 133 patients with AC joint displacement were evaluated. Mean Age: approximately 31.90 years. 81.92 of these injuries occurred during sports practice. Surgical Procedures Used: titanium plates fixation (49 patients), arthroscopy (24), single tunnel technique (30) and coracoid sling technique (30). The results of the visual analog scale and Constant-Murley scores varied between the techniques used. Twenty-two complications after surgical treatment were identified. Conclusion: A significant variability of operative techniques can be used in the surgical approach of acromioclavicular dislocation, such as arthroscopy, single tunnel, coracoid sling and titanium plates. Although it presented excellent functional results compared to the other three tech

关键词： Acromioclavicular Joint Shoulder Dislocation Surgical Procedure Postoperative Complications Postoperative Care

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Hydroelectrolytic and Energetic Replenisher in Horses Undergoing Marcha Training

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Open Journal of Veterinary Medicine 2024年第8期14卷 203-216页

作者： José D. Ribeiro filho Bruna M. Ribeiro Micheline O. silva Samuel R. Alves Anaïs C. Benitez Waleska M. f. Dantas Marcel f. B. Avanza Raffaella B. C. Teixeira pedro Ancelmo N. Ermita Laice A. silva Rinaldo B. Viana Hélio C. Manso filho Department of Veterinary Federal University of Viosa Viosa Brazil Institute of Studies of the Wet Tropic Federal University of Southern and Southeastern Par Xinguara Brazil Department of Veterinary Clinic and Surgery Federal University of Minas Gerais Belo Horizonte Brazil Institute of Animal Health and Production Federal Rural University of Amazonia Belm Brazil Zootecnics Department Federal Rural University of Pernambuco Recife Brazil

The study aimed to assess the clinical, laboratory, and blood gas analysis of horses undergoing Marcha training and the effects of voluntary ingestion of hydroelectrolytic and energy replenishers after exercise. Eight horses of both genders aged between 5 and 10 years, were included in the study. The exercise consisted of a 10-min warm-up followed by 45 min uninterrupted Marcha on a flat dirt track in the morning. After exercise, the horses received one of the following treatments: Drinking water (control group);Hydroelectrolytic and energy replenisher containing sodium chloride, potassium chloride, calcium acetate, magnesium chloride, sodium citrate, dextrose, maltodextrin, and sucrose in three different concentrations (Replenishers A, B, and C). The horses were distributed across the four treatments in a 4 × 4 Latin Squares design using a Split-plot system with 48-hr intervals. Clinical and laboratory evaluations were conducted at four time points: T0 - 5 min before exercise;T1 - up to 5 min after exercise;T2 - 2 hr after starting treatment;and T4 - 4 hr after beginning treatment. Concentrations of urea, creatinine, lactate, phosphorus, and ionized calcium significantly changed after exercise. An increase in blood pH and a decrease in chloride concentrations were observed when replenishers B and C were offered after exercise. The replacements were ingested spontaneously by the animals in a volume greater than that of the control group (water). Replacement B was the most ingested by the animals, demonstrating its greatest potential.

关键词： Dehydration Electrolyte Replacement Exercise Rehydration Voluntary Intake

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Effect of radiative loss mechanisms on fIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.L silva L.A.O.Nunes S.M.Lima L.H.C.Andrade Optical and Photothermal Spectroscopy Group(GEOf) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(fIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the fIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)f_(5/2)→^(4)I_(9/2)/^(4)f_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

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t-SNE:A study on reducing the dimensionality of hyperspectral data for the regression problem of estimating oenological parameters

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Artificial Intelligence in Agriculture 2023年第1期7卷 58-68页

作者： Rui silva pedro Melo-Pinto CITAB-Centre for the Research and Technology of Agro-Environmental and Biological Sciences Inov4Agro-Institute for InnovationCapacity Building and Sustainability of Agri-Food ProductionUniversidade de Trás-os-Montes e Alto DouroQuinta dos PradosVila Real 5000-801Portugal Departamento de Engenharias Escola de Ciências e TecnologiaUniversidade de Trás-os-Montes e Alto DouroQuinta dos PradosVila Real 5000-801Portugal

In recent years there is a growing importance in using machine learning techniques to improve procedures in precision agriculture:in this work we perform a study on models capable of predicting oenological parameters from hyperspectral images of wine grape berries,a specially relevant topic to boost production tasks for ***,we explore the capabilities of a novel technique mostly used for visualization,t-Distributed Stochastic Neighbor Embedding(t-SNE),for reducing the dimensionality of the highly complex hyperspectral data and compare its performance with Principal Component Analysis(PCA)method,which despite the introduction of many nonlinear dimensionality reduction techniques over the years,had achieved the best results for real-world data across several studies in *** we explore the potential of Kernel t-SNE,an extension to the t-SNE method that allows for the usage of the technique in streaming data or online *** results show that,in a direct comparison,t-SNE achieves better metrics than PCA for most of the data sets in this work and that the regressor(Support Vector Regression,SVR)performs better with the t-SNE reduced features as inputs,accomplishing better predictions with lower error *** the results with current literature,our shallow learning model paired with t-SNE achieves either better or on par results than those reported,even competing with more advanced models that use deep learning techniques,which should propel the introduction of t-SNE in more studies that require dimensionality reduction.

关键词： Hyperspectral images Dimensionality reduction Regression T-SNE Support vector machines Wine grape berries

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Validation and adaptation of the Physical Activity Enjoyment Scale (PACES) in fitness group exercisers

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Journal of Sport and Health Science 2020年第4期9卷 352-357页

作者： pedro Teques Luıs Calmeiro Carlos silva Carla Borrego N2i Polytechnic Institute of Maia Research CentreMaia 4475-690Portugal CIPER Interdisciplinary Centre for the Study of Human PerformanceCruz Quebrada 1499-002Portugal Abertay University School of Social and Health SciencesDundee DD11HGUK Polytechnic Institute of Santarem Sport Sciences School of Rio MaiorSantarem 2001-904Portugal CIEQV—Life Quality Research Center Santarem 2001-904Portugal

Background:Recently,Mullen et al.(2011)presented an 8-item version of the Physical Activity Enjoyment Scale(PACES)that provides a valid instrument for assessing enjoyment in physical *** present paper investigated the psychometric properties of a Portuguese adaptation of ***:After a process of back-to-back translation into Portuguese,395 members of fitness centers who ranged in age from 18 to 66 years(31.11§8.90,mean§SD)completed the translated version of the *** average,participants had 3.2 years of experience in fitness group classes and practiced for approximately 3.3 times per ***:An initial exploratory factor analysis(n=139)revealed a unidimensional structure with factor loadings ranging from 0.79 to *** also showed acceptable internal consistency.A confirmatory factor analysis in an independent sample(n=256)provided additional support for the unidimensional structure of the *** addition,moderate positive correlations between enjoyment and intrinsic and identified regulation,and moderate negative correlations between enjoyment and external and amotivation,demonstrate the convergent validity of the ***,measurement invariance between 2 independent samples was also ***:The 8-item Portuguese version of PACES is a valid and reliable instrument for measuring enjoyment of physical activity in Portuguese adult fitness exercisers,and it is therefore suitable to use as a measure of affect in exercise adherence interventions studies.

关键词： Confirmatory factor analysis Construct validity Enjoyment Exploratory factor analysis fitness Measurement invariance Self-determination theory

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Structural and photoluminescent properties of the MgGa_(2)O_(4):Co^(2+)ceramic compound revisited after two decades

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Journal of Advanced Ceramics 2015年第4期4卷 267-271页

作者： S.S.pedro M.A.f.M.DA silva A.LÓPEZ,L.P.SOSMAN Instituto de física Universidade do Estado do Rio de JaneiroRJ 20550-900Brazil

In this work,we revisit and show how the structural and photoluminescent properties of the MgGa_(2)O_(4) ceramic compound have been kept unchanged for more than two *** obtained results confirm the high quality,radiative efficiency,and chemical stability of this ceramic,proving that the material is a strong candidate to be used in optical device applications with relatively long useful life.

关键词： ceramic compound cobalt solid-state reaction photoluminescence

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Idiopathic sudden sensorineural hearing loss:Effectiveness of salvage treatment with low-dose intratympanic dexamethasone

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Journal of Otology 2021年第1期16卷 6-11页

作者： pedro Salvador francisco Moreira da silva Rui fonseca Department of Otorhinolaryngology Hospital Senhora da OliveiraGuimaraesPortugal

Objectives:To evaluate hearing outcome of salvage treatment with intratympanic steroids(ITS)in idiopathic sudden sensorineural hearing loss(ISSNHL)refractory to initial systemic steroid(SS)*** and methods:A retrospective medical chart review was conducted on 54 consecutive patients with ISSNHL refractory to *** treatment with a low dose intratympanic dexamethasone(4 mg/ml)was offered after one week of primary *** were divided into two groups:25 patients accepted ITS(treatment group)and 29 patients did not undergo additional treatment(control group).A pure tone average(PTA)gain of at least 10 dB was considered hearing ***:Hearing improvement rate was higher in ITS group compared to control group(40%vs.13.8%,p=0.035).A mean PTA improvement of 8.6±9.8 dB was observed in the ITS group and,whereas the control group had an average hearing gain of 0.7±2 dB(pficant hearing gain in ITS group at all tested frequencies compared to control group(pf the selected variables,identified intratympanic steroid treatment as the only independent prognostic factor for hearing improvement(OR=4.2,95%CI:1.1e15.7;p=0.04).Conclusion:Intratympanic low dose dexamethasone is effective in patients with incomplete hearing recovery after primary systemic steroid treatment.

关键词： Intratympanic Steroids Salvage Sudden sensorineural hearing loss Idiopathic

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