Ciência e Natura最新文献_第2页

Comparative analysis of deterministic and reliability-based structural optimization methods 确定性和可靠性结构优化方法的比较分析

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x74335

Carla Simone de Albuquerque, Mauro de Vasconcellos Real

{"title":"Comparative analysis of deterministic and reliability-based structural optimization methods","authors":"Carla Simone de Albuquerque, Mauro de Vasconcellos Real","doi":"10.5902/2179460x74335","DOIUrl":"https://doi.org/10.5902/2179460x74335","url":null,"abstract":"Optimization is the act of obtaining the best possible result under established conditions. Usually, the optimization of a structural design is done considering the structure's dimensions, the materials' properties, and the loads as deterministic values. This way, the optimization process can lead to a more economical design without guaranteeing that this structure is safe. In practice, there are always uncertainties about the final dimensions of the built structure, material properties, and loads. Then, the need arises to use design optimization techniques based on reliability to guarantee a project that is both economical and safe. This objective is achieved by including uncertainties in the optimization process. This article evaluates the parameters that determine the global minimum of the optimization methods DDO (Deterministic Design Optimization) and RBDO (Reliability-Based Design Optimization). This work aims to compare the structural optimization methods of DDO and RBDO through an example. The results are obtained through the codes of the methods implemented in the Python language and show that when comparing the two optimization methods, the presence of uncertainties alters the optimal solution.","PeriodicalId":348075,"journal":{"name":"Ciência e Natura","volume":"25 31","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138624350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Parameter estimation in the pollutant dispersion problem with Physics-Informed Neural Networks 利用物理信息神经网络对污染物扩散问题进行参数估计

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x74615

Roberto Mamud Guedes da Silva, Helio dos Santos Migon, A. S. Silva Neto

引用次数: 0

Optimization of reinforced concrete structures using population-based metaheuristic algorithms 利用基于群体的元启发式算法优化钢筋混凝土结构

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x74927

Rodrigo Reis Amaral, Lamartini Fontana Barazzutti, Herbert Martins Gomes

{"title":"Optimization of reinforced concrete structures using population-based metaheuristic algorithms","authors":"Rodrigo Reis Amaral, Lamartini Fontana Barazzutti, Herbert Martins Gomes","doi":"10.5902/2179460x74927","DOIUrl":"https://doi.org/10.5902/2179460x74927","url":null,"abstract":"For many industrial activities, ideal projects are achieved by comparing the solution of alternative projects with those already executed. The feasibility of solutions plays an important role in these activities. For example, the underlying objective (cost, profit, etc.) estimated for each project solution is calculated and the best solution is adopted. This is the usual procedure followed by many constructors due to time and resource limitations. However, in many cases, this method is followed simply by a lack of knowledge of existing optimization procedures. In this context, a comparative study of population-based metaheuristic algorithms applied to a case study of a reinforced concrete beam design reinforced with a polymer matrix with carbon fibers will be presented. Evolutionary algorithms have the ability to determine the optimal values of the design variables without disregarding the restrictions on ACI-318 and ACI-440 standards while minimizing the reinforcement area for each beam (cost). The comparative study shows that not all presented algorithms violated design constraints. In addition, it can be said that the values found for the design variables present a low dispersion around the mean value of the objective function.","PeriodicalId":348075,"journal":{"name":"Ciência e Natura","volume":" 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138611906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A preliminary study on the application of the two-space nonperiodic asymptotic homogenization method to the EEG forward problem with continuously differentiable coefficient 将双空间非周期性渐近均质化方法应用于具有连续可变系数的脑电图前向问题的初步研究

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x75138

Roberto Martins da Silva Décio Júnior, A. De Cezaro, Leslie Darien Pérez Fernández, Julián Bravo Castillero

引用次数: 0

Analysis of the calibration and validation of hydrodynamic simulations with TELEMAC-3D model of the Patos Lagoon 帕托斯泻湖 TELEMAC-3D 模型流体力学模拟的校准和验证分析

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x75144

Nágila Veiga Adrião Monteiro, Juliana Costi, Pablo Dias da Silva, Elisa Helena Leão Fernandes, Liércio André Isoldi

{"title":"Analysis of the calibration and validation of hydrodynamic simulations with TELEMAC-3D model of the Patos Lagoon","authors":"Nágila Veiga Adrião Monteiro, Juliana Costi, Pablo Dias da Silva, Elisa Helena Leão Fernandes, Liércio André Isoldi","doi":"10.5902/2179460x75144","DOIUrl":"https://doi.org/10.5902/2179460x75144","url":null,"abstract":"This work presents the analysis of the calibration and validation of the computational model for two configurations of the Jetties of the Rio Grande Barra for hydrodynamic studies of the Patos Lagoon and the continental shelf of southern Brazil. The model used was TELEMAC-3D, which solves the three-dimensional Navier-Stokes equations, considering the hydrostatic hypothesis, to describe the dynamics of free surface geophysical fluids. We developed two finite element triangular meshes, with about 75.000 elements and seven sigma levels. The numerical domain reaches depths up to 2.427 m, with fluvial and oceanic liquid boundaries. The horizontal turbulence model adopted was Smagorinsky and the vertical model of mixing length. Current velocity data obtained from December 2005 were used for calibration, varying the coefficient of wind friction, horizontal and vertical velocity diffusion, and the salinity tracer. The coefficient of wind influence was the factor that most influenced the model results. The calculated Relative Mean Absolute Error was 0.383 dn. for surface and 0.167 dn. for depth, rated good and excellent, respectively. For validation, we evaluated the model performance on reproducing the salinity behavior, related to the depth of the environment, in January 2017. The calculated Root Mean Square Error was 7.37 dn. and the Relative Mean Absolute Error was 0.228 dn., rating the model performance as good. These variances between metrics is uniformly acceptable for real models. Salt transport is a complex phenomenon and depends on both advective and diffusive transport. Thus, it is possible to conclude that he proposed computational model is able to reproduce a complex phenomenon reliably.","PeriodicalId":348075,"journal":{"name":"Ciência e Natura","volume":" 15","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138609865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Avaliação numérica do desempenho térmico de trocador de calor solo-ar em habitação de interesse social nas zonas bioclimáticas brasileiras ZB 3 e ZB 4 对巴西 ZB 3 和 ZB 4 生物气候区社会住房中土壤-空气热交换器的热性能进行数值评估

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x74487

Paula Wrague Moura, L. R. Leite, Márcio Wrague Moura, Luiz Alberto Oliveira Rocha, Elizaldo Domingues dos Santos, Ruth da Silva Brum, Liércio André Isoldi

{"title":"Avaliação numérica do desempenho térmico de trocador de calor solo-ar em habitação de interesse social nas zonas bioclimáticas brasileiras ZB 3 e ZB 4","authors":"Paula Wrague Moura, L. R. Leite, Márcio Wrague Moura, Luiz Alberto Oliveira Rocha, Elizaldo Domingues dos Santos, Ruth da Silva Brum, Liércio André Isoldi","doi":"10.5902/2179460x74487","DOIUrl":"https://doi.org/10.5902/2179460x74487","url":null,"abstract":"O Trocador de Calor Solo-Ar (TCSA) é um dispositivo onde o ar ambiente externo é resfriado ou aquecido ao circular dentro de dutos enterrados no solo, podendo trazer benefícios no sentido de reduzir o consumo de energia e proporcionar condições de conforto térmico. Esse sistema tem sido empregado em diversos países e em diferentes contextos climáticos, porém, pouco explorado no Brasil. A utilização dessa tecnologia em conjunto às estratégias bioclimáticas favorece as edificações, aumentando sua eficiência energética. Esse estudo tem como objetivo avaliar o desempenho térmico de um TCSA conjuntamente a parâmetros de otimização da envoltória da edificação, em duas zonas bioclimáticas brasileiras e propor estratégias que potencializem a eficiência energética nas edificações. O estudo consiste na validação e verificação de um modelo computacional e nas avaliações térmicas de uma habitação de interesse social (HIS), no qual serão modificadas, combinadas e investigadas características de orientação solar, envelope térmico e a instalação de um TCSA, derivando-o em modelos propostos. Essas avaliações foram realizadas através de simulação dinâmica com o programa EnergyPlus™. Os resultados demonstraram que a instalação de um TCSA em uma HIS trazem melhorias no desempenho térmico dos ambientes, contribuindo, assim, para que projetos futuros possam contar com referências e parâmetros validados.","PeriodicalId":348075,"journal":{"name":"Ciência e Natura","volume":" 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138613223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of EAHE through a coupled mathematical model solved by Laplace transform and Gaver-Stehfest algorithm 通过拉普拉斯变换和 Gaver-Stehfest 算法求解的耦合数学模型分析 EAHE

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x74745

Felipe Augusto Silva Martins, G. J. Weymar, Igor da Cunha Furtado, F. Tumelero, Ruth da Silva Brum, R. Quadros, Daniela Buske

{"title":"Analysis of EAHE through a coupled mathematical model solved by Laplace transform and Gaver-Stehfest algorithm","authors":"Felipe Augusto Silva Martins, G. J. Weymar, Igor da Cunha Furtado, F. Tumelero, Ruth da Silva Brum, R. Quadros, Daniela Buske","doi":"10.5902/2179460x74745","DOIUrl":"https://doi.org/10.5902/2179460x74745","url":null,"abstract":"The earth-air heat exchangers (EAHEs) are devices that are shown to be a great alternative to assist in the thermal comfort of buildings, mainly due to their low energy cost. The proposed model considers the heat exchange between the soil, the duct and the air, generating coupled equations. This work seeks to employ and verify EAHE applications in two scenarios, first in a literature experiment and then in a EAHE application in Pelotas. In both scenarios, it is considered that the soil and air temperature functions are time dependent. The solution is obtained by applying the Laplace transform and for the inversion of the integral transform the numerical method known as the Gaver-Stehfest Algorithm was used. The obtained results show that the proposed model follows the behavior of the experimental data. In addition to the experimental data, the proposed model was compared with the analytical model by Nóbrega, where the results had a small variation (of 0.20 ºC between them) by considering the heat transfer process in the duct material, modeling a more close to the real situation.","PeriodicalId":348075,"journal":{"name":"Ciência e Natura","volume":"26 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138624368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Verification of structural reliability of a highway bridge in the state of Rio Grande do Sul 验证南里奥格兰德州一座公路桥的结构可靠性

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x73885

Vinicius Heidtmann Avila, Mauro de Vasconcellos Real

引用次数: 0

Computational model verification and numerical analysis of plate buckling due to combined loading 组合加载导致的板材屈曲的计算模型验证和数值分析

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x75137

G. R. Baumgardt, Mauro de Vasconcellos Real, Paulo Roberto de Freitas Teixeira, Elizaldo Domingues dos Santos, T. D. Silveira, Liércio André Isoldi

{"title":"Computational model verification and numerical analysis of plate buckling due to combined loading","authors":"G. R. Baumgardt, Mauro de Vasconcellos Real, Paulo Roberto de Freitas Teixeira, Elizaldo Domingues dos Santos, T. D. Silveira, Liércio André Isoldi","doi":"10.5902/2179460x75137","DOIUrl":"https://doi.org/10.5902/2179460x75137","url":null,"abstract":"Thin plates are structures widely used in different industries, due to their mechanical properties. They are often subjected to combined loading, which can cause an undesired phenomenon called buckling. In this sense, the present work analyzes the elasto-plastic buckling behavior of thin steel plates that are simply supported and subjected to in-plane uniaxial or biaxial compression combined with lateral pressure. To obtain the ultimate stress of the plates, a computational model was developed using the finite element method. Initially, the computational model was verified through previous numerical results from the literature. Then, a case study was carried out considering a rectangular plate geometry with an aspect ratio of b/a = 0.5 (where a and b are the length and width of the plate, respectively), under biaxial compression and varying the lateral loading from 0 to 0.152 MPa, aiming to analyze its elasto-plastic buckling behavior. The results indicated that the computational model was adequately verified. From the case study, it was inferred that the load step plays an important role in the numerical prediction accuracy of the elasto-plastic buckling mechanical behavior of plates In addition, the application of initial imperfection for small lateral pressures has little influence on ultimate stress, while for larger lateral pressures it does not generate influence.","PeriodicalId":348075,"journal":{"name":"Ciência e Natura","volume":" 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138615408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Application of constructal theory for the construction of an arrangement of heated blocks inserted in a channel subject to flows with forced convection 将构造理论应用于建造插入受强制对流影响的通道中的加热块排列结构

Ciência e Natura Pub Date : 2023-12-01 DOI: 10.5902/2179460x74568

Diego Mion do Carmo, Liércio André Isoldi, Luiz Alberto Oliveira Rocha, M. Errera, Elizaldo Domingues dos Santos

{"title":"Application of constructal theory for the construction of an arrangement of heated blocks inserted in a channel subject to flows with forced convection","authors":"Diego Mion do Carmo, Liércio André Isoldi, Luiz Alberto Oliveira Rocha, M. Errera, Elizaldo Domingues dos Santos","doi":"10.5902/2179460x74568","DOIUrl":"https://doi.org/10.5902/2179460x74568","url":null,"abstract":"This work shows an analysis of the construction of the geometric arrangement of blocks mounted on the surfaces of a channel subject to a laminar, incompressible flow, with forced convection in a two-dimensional domain. The construction is carried out through a construction function based on the system performance indicator, i.e., the heat transfer rate from the arrangement to the fluid flow. For the assembly of the arrangement, a methodology based on the principles of the Constructal Theory is used. To solve the convection problem, the mass, momentum and energy conservation equations are solved with the Finite Volume Method, more precisely using the FLUENT software. The objective of this work is to understand how the construction of the initial blocks of the array (N = 3 blocks) occurs in an area occupied by the channel in flows with forced convection and Reynolds and Prandtl numbers of ReH = 100 and Pr = 0.71. The best and worst cases for N = 2 led to an increase of 93.21% and 28.59%, respectively, compared to the N = 1 case. Results demonstrated that the construction that led to the best thermal performance was the configuration where there is the highest momentum between blocks (intensifying the convective heat transfer coefficient) and with the lowest interaction between the thermal boundary layers, which is in agreement with the principle of optimal distribution of imperfections.","PeriodicalId":348075,"journal":{"name":"Ciência e Natura","volume":" 88","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138613492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0