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GIS-Based Methodology for Crash Prediction on Single-Lane Rural Highways

Journal of Geographic Information System 2021年第2期13卷 98-121页

作者： Márcia Macedo Emilia Kohlman Rabbani Maria Maia Marlos Macedo Bianca Ferreira Post-Graduate Program in Civil Engineering UPE Recife Brazil Post-Graduate Program in Systems Engineering UPE Recife Brazil Graduate Program in Architecture and Urban Planning UNICAP Recife Brazil

Due to the need to update the current guidelines for highway design to focus on safety, this study sought to build an accident prediction model using a Geographic Information System (GIS) for single-lane rural highways, with a minimum of statistically significant variables, adequate to the Brazilian reality, and improve accident prediction for places with similar characteristics. A database was created to associate the accident records with the geometric parameters of the highway and to fill in the gaps left by the absence of geometric highway plans through geometric reconstitution or semi-automatic extraction of highways using satellite images. The Generalized Estimating Equation (GEE) method was applied to estimate the coefficients of the model, assuming negative distribution of the binomial error for the count of observed accidents. The accident frequency and annual average daily traffic (AADT) were analyzed, along with the spatial and geometric characteristics of 215 km of federal single-lane rural highways between 2007 and 2016. The GEE procedure was applied to two models having three variations of distinct homogeneous segmentation, two based on segments and one based on the kernel density estimator. To assess the effect of constant traffic, two more variations of the models using AADT as an offset variable were considered. The predominant correlation structure in the models was the exchangeable. The principal contributing factors for the occurrence of collisions were the radius of the horizontal curve, the grade, segment length, and the AADT. The study produced clear indicators for the design parameters of roadways that influence the safety performance of rural highways.

关键词： Roads GEE Single-Lane Rural Highways GIS Crash Prediction

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Analytical process of the energy efficiency in building improvement alternatives

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ENERGY REPORTS 2022年 8卷 31-37页

作者： Chanpichaigosol, Nuttapon Chaichana, Chatchawan Buachart, Chinnapat Tochaiwat, Kongkoon Rinchumphu, Damrongsak Chiang Mai Univ Graduated Doctorals Degree Program Energy Engn Fac Engn Chiang Mai 50200 Thailand Chiang Mai Univ Dept Mech Engn Fac Engn Chiang Mai 50200 Thailand Chiang Mai Univ Dept Civil Engn Fac Engn Chiang Mai 50200 Thailand Thammasat Univ Fac Architecture & Planning Pathum Thani 12121 Thailand Chiang Mai Univ Ctr Excellence Nat Disaster Management CENDIM Chiang Mai 50200 Thailand

Thailand has set criteria called Building Energy Code (BEC) for building energy conservation). It is set OTTV as a standard value. Only the total amount of heat transferred through the walls in each direction of the building is considered. However, this approach cannot indicate the energy consumption needs and consider additional building improvement costs to meet the standard. This study presents the building improvement guidelines for reducing energy consumption by considering the changing construction costs to determine the efficiency of the cost's impact and the changing energy values. These are the variables describing the interest for each alternative in terms of efficiencies and investment worthiness. Therefore, the building modelling created by Autodesk Revit and DesignBuilder is used to analyse the energy value, which needs calibration for Base Case Modelling. For the calibration, the past-3-year electricity consumption of the building is used, and the retroactive electricity value equals 55,920 kWh/year. In addition, comparing the energy consumption values obtained from the models, its value is 59,321 kWh/year, showing that the difference is only 5.73% before using the models to create the alternative cases. In this study, two alternative guidelines for decision-making of the building improvements are presented: (1) changing the building envelope from a single-layer to a double-layer brick wall, (2) adding the PU foam insulation and covering with gypsum board. The values of both alternatives regarding the effects on costs and changing energy consumption are 3.67 and 3.43 Wh/year/Bath, respectively. To conclude, the efficiency of the alternatives is quite similar, resulting in more remarkableness for the building improvement options. Thus, this can be used as a guideline for making decisions about building improvements in the future. (C) 2022 The Author(s). Published by Elsevier Ltd.

关键词： Autodesk Revit DesignBuilder Energy consumption Energy simulation

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A frequency-domain approach for damage detection in welded structures

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FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES 2021年第4期44卷 1134-1148页

作者： Ronchei, Camilla Vantadori, Sabrina Carpinteri, Andrea Iturrioz, Ignacio Rodrigues, Roberto Issopo Scorza, Daniela Zanichelli, Andrea Univ Calabria Dept Civil Engn Arcavacata Di Rende Italy Univ Parma Dept Engn & Architecture Parco Area Sci 181-A I-43124 Parma Italy Univ Fed Rio Grande do Sul Mech Postgrad Program Porto Alegre RS Brazil Univ Naples Parthenope Dept Engn Naples Italy

The goal of the present paper is to apply a multiaxial fatigue criterion, formulated in frequency-domain, to welded components. In particular, the proposed procedure requires (i) to evaluate the stress field at the so-called hotspot and (ii) to compute the fatigue damage. A case study, represented by fillet-welded tubular T-joints under random loading, is examined to assess the validity of the above procedure in estimating the crack nucleation position. Finally, the above theoretical results are also compared with those derived by means of a similar procedure, which has recently been proposed by some of the present authors, but formulated in time-domain.

关键词： fillet-welded joints frequency-domain criterion hotspot approach multiaxial random fatigue

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Flexible cylinder flow-induced vibration

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PHYSICS OF FLUIDS 2022年第1期34卷 1-22页

作者： Ma, Leixin Lin, Ke Fan, Dixia Wang, Jiasong Triantafyllou, Michael S. MIT Dept Mech Engn Cambridge MA 02139 USA Shanghai Jiao Tong Univ Sch Naval Architecture Ocean & Civil Engn Dept Engn Mech Shanghai 200240 Peoples R China Queens Univ Dept Mech & Mat Engn Kingston ON K7M 3N9 Canada Westlake Univ Sch Engn Hangzhou 310024 Zhejiang Peoples R China MIT Sea Grant Coll Program Cambridge MA 02139 USA

In this paper, we conducted a selective review on the recent progress in physics insight and modeling of flexible cylinder flow-induced vibrations (FIVs). FIVs of circular cylinders include vortex-induced vibrations (VIVs) and wake-induced vibrations (WIVs), and they have been the center of the fluid-structure interaction (FSI) research in the past several decades due to the rich physics and the engineering significance. First, we summarized the new understanding of the structural response, hydrodynamics, and the impact of key structural properties for both the isolated and multiple circular cylinders. The complex FSI phenomena observed in experiments and numerical simulations are explained carefully via the analysis of the vortical wake topology. Following up with several critical future questions to address, we discussed the advancement of the artificial intelligent and machine learning (AI/ML) techniques in improving both the understanding and modeling of flexible cylinder FIVs. Though in the early stages, several AL/ML techniques have shown success, including auto-identification of key VIV features, physics-informed neural network in solving inverse problems, Gaussian process regression for automatic and adaptive VIV experiments, and multi-fidelity modeling in improving the prediction accuracy and quantifying the prediction uncertainties. These preliminary yet promising results have demonstrated both the opportunities and challenges for understanding and modeling of flexible cylinder FIVs in today's big data era.

关键词： Circular cylinders

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Adsorption of humic acid fractions by a magnetic ion exchange resin

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WATER SCIENCE AND TECHNOLOGY 2022年第7期85卷 2129-2144页

作者： Ding, Lei Wang, Dandan Li, Ling Jia, Yunhan Ma, Jiangya Wang, Feifei van der Hoek, Jan Peter Anhui Univ Technol Engn Res Ctr Biomembrane Water Purificat & Utiliza Minist Educ Maanshan 243002 Peoples R China Anhui Univ Technol Sch Civil Engn & Architecture Maanshan 243002 Peoples R China Shanghai Univ Sch Environm & Chem Engn Shanghai 200444 Peoples R China Delft Univ Technol Dept Water Management NL-2628 CN Delft Netherlands Waternet Res & Innovat Program NL-1096 AC Amsterdam Netherlands

Natural organic matter in waters varies in different fractions. To better understand the removal of different fractions by a magnetic ion exchange (MIEX) resin and the mechanism behind it, this study investigated adsorption kinetics, equilibrium and thermodynamics of humic acid (HA) fractions with different hydrophilic-hydrophobic properties and molecular weights on MIEX resin through a series of batch experiments. MIEX resin can effectively remove approximately 40% of hydrophilic and 30% of hydrophobic HA components, as well as approximately 44% of molecular weight (MW) <10 kDa to some degree. The removal efficiency of HA fractions by MIEX resin reduced with the increase of pH from 6 to 9. Adsorption kinetics of different HA fractions on MIEX resin fitted the pseudo-second-order model well. With the increase of MW of HA from <1 kDa to >10 kDa, the time to reach adsorption equilibrium reduced from 180 to 120 min. It took more time for the hydrophilic fractions (140 min) to reach the equilibrium than for hydrophobic HA fractions (120 min). The Sips model fitted the adsorption equilibrium data of HA fractions on MIEX resin well. It was revealed that the adsorption of HA fractions on MIEX resin was spontaneous, endothermic and an entropy driven process, and the chemisorption might dominate the adsorption of HA components on MIEX resin. This study is of great significance to the design of magnetic ion exchange resin reactors and the optimization of operational parameters for the removal of natural organic matter with different hydrophilic-hydrophobic properties and molecular weights in different water sources.

关键词： adsorption HA ion exchange MIEX resin molecular weight

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Shear-bond behavior of self-compacting geopolymer concrete to conventional concrete

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CONSTRUCTION AND BUILDING MATERIALS 2022年第0期321卷 126167-126167页

作者： Purwanto Ekaputri, Januarti Jaya Nuroji Indriyantho, Bobby Rio Han, Aylie Gan, Buntara Sthenly Univ Diponegoro Dept Civil Engn Semarang 50275 Indonesia Inst Teknol Sepuluh Nopember Dept Civil Engn Surabaya 60111 Indonesia Univ Diponegoro World Class Res Program Semarang 50275 Indonesia Nihon Univ Dept Architecture Coll Engn Koriyama Fukushima 9638642 Japan

The shear-bond behavior of two mechanically different concretes is fundamental when conducting external reinforcement, retrofitting, or repair. The two components are designed to possess full strain compatibility in sustaining the stress transfer between the two parts throughout the loading sequence. This work investigated the shear-bond behavior between conventional and self-compacting geopolymer concrete based on the push-off method. The influence of surface roughness on the bond behavior was studied, and a finite element model was constructed and validated to the experimental data. Surprisingly, the chemical bond characteristics of geopolymer concrete have little effect on the bond strength as compared to conventional concrete having the same compression strengths, but significantly influences the load-slip pattern of the interface. As expected, the bond strength was positively influenced by the interface roughness. All failure modes were unmistakably brittle. The strain deformation pattern generated from the finite element model underlined that large strains and stresses were present at the far ends in the interface, where initial cracking was detected in these regions. The study concluded that self-compacting geopolymer concrete is a perfect solution for older structure's external strengthening or retrofitting. This material has a better sustainable and a more environmentally friendly character.

关键词： Self-compacting geopolymer concrete Shear-bond Bond-strength Interface Roughness Finite element model

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Adaptive behaviour and air conditioning use in Brazilian residential buildings

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BUILDING RESEARCH AND INFORMATION 2021年第5期49卷 496-511页

作者： Ramos, Greici Lamberts, Roberto Abrahao, Karla C. F. J. Bandeira, Fernanda B. Barbosa Teixeira, Carla Fernanda de Lima, Mariana Brito Broday, Evandro Eduardo Castro, Adriana P. A. S. Leal, Lilianne de Queiroz De Vecchi, Renata De Zorzi, Lizia De Moraes Dornelles, Kelen A. Duarte, Silvia Faisca, Renata G. Fontenelle, Marilia Freitas, Thyago Atem, Camila Gregorio Grigoletti, Giane Maciel, Liliane de Moraes, Clelia Mendonca Mueller, Cecilia M. Sartori, Thais Silva, Barbara Silva, Caio da Silva, Marcelle Vilar Silveira, Ana Lucia Souza, Roberta V. G. Xavier, Antonio Augusto Univ Fed Santa Catarina Dept Civil Engn LabEEE Bldg Energy Efficiency Lab Florianopolis SC Brazil Univ Fed Minas Gerais Sch Architecture Grad Program Built Environm & Sustainable Heritag Belo Horizonte MG Brazil Univ Estadual Campinas Fac Civil Engn Architecture & Urbanism Campinas Brazil Univ Fed Sergipe Labcon Lab Environm Comfort Laranjeiras Brazil Fed Inst Ceara Dept Environm Engn Juazeiro Do Norte Brazil UTFPR Fed Univ Technol Ponta Grossa LabErgo Ergon Lab Ponta Grossa Parana Brazil Univ Estadual Campinas DAC Dept Architecture & Construct Campinas Brazil Univ Fed Campina Grande UACTA Dept Civil Engn Pomba Brazil Univ Ctr Serra Gaucha FSG Ctr Innovat & Technol Caxias Do Sul RS Brazil Univ Sao Paulo IAU Inst Architecture & Urbanism Sao Carlos Brazil Univ Paulista Fac Architecture & Urbanism Campus Santos Santos SP Brazil Fluminense Fed Univ Dept Civil Engn Niteroi RJ Brazil Fluminense Fed Univ Dept Architecture Niteroi RJ Brazil Ctr Higher Educ Palmas LABCA Environm Comfort Lab Palmas Brazil Filadelfia Univ Ctr Dept Architecture & Urbanism UniFil Londrina Parana Brazil Univ Fed Santa Maria LASAC Sustainabil Built Environm Lab Santa Maria RS Brazil Santo Agostinho Fac Montes Claros FASA Dept Architecture & Urbanism Montes Claros MG Brazil Univ Fed Sao Carlos Urban Engn Dept Urban Mobil Coordinating Bo Project & Pos Doc Araraquara City Hall Araraquara SP Brazil Belas Artes Univ Ctr Environm Comfort Sao Paulo Brazil Univ Brasilia Dept Architecture & Urbanism SICAC Computat Simulat Built Environm Gama Brazil UnB Univ Brasilia LACAM Lab Environm Control Brasilia DF Brazil Univ Fed Amapa Dept Exact & Technol Sci DCET Macapa Brazil Univ Fed Piaui DCCA Dept Civil Construct & Architecture Teresina Brazil Univ Fed Minas Gerais Labcon Lab Environm Comfort Grad Program Built Environm & Sustainable Heritag Technol Design Architecture & Urbanism Dept Belo Horizonte MG Brazil Univ Estadual Londrina UEL Dept Civil Engn Londrina

This paper aims to understand and characterize occupant behaviour from a perspective of air conditioner (AC) usage. Therefore, it analyses data collected via a questionnaire applied throughout the Brazilian territory, which resulted in 3,259 valid answers explored by non-parametric statistical methods. The main results obtained were: (i) 89% of interviewed occupants prefer naturally ventilated environments at home;(ii) their preference impacts their behaviour, as those who prefer naturally ventilated environments tend to ventilate their house instead of turning on the air conditioner;(iii) climate and family income influence the availability of appliances, i.e. 93.2% of the high-income groups have at least one AC at home in extremely hot climates;(iv) there are groups with a tendency of high AC use, especially those who use AC often, also use it for a longer period of time;and (v) there is a significant difference between the setpoint temperature used in different climates;for instance, the lowest setpoint temperature is used in the hottest climate. This paper intends to contribute to a better understanding of occupants' preferences and behavioural tendencies, especially in Brazilian residences and hot climates, while showing the influence of variables like family income and climate on such issues.

关键词： Thermal comfort air conditioning adaptive behaviour occupant behaviour

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Drag Forces after Thoracic Endovascular Aortic Repair. General Review of the Literature

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ANNALS OF VASCULAR SURGERY 2021年 75卷 479-488页

作者： Domanin, Maurizio Bissacco, Daniele Romarowsky, Rodrigo M. Conti, Michele Auricchio, Ferdinando Ferraresi, Marco Trimarchi, Santi Univ Milan Dept Hlth & Community Sci Milan Italy Fdn IRCCS Ca Grande Osped Maggiore Policlin Milan Milan Italy Univ Pavia Dept Civil Engn & Architecture Pavia Italy Univ Milan Teaching Sch Vasc Surg Vasc Surg Resident Program Milan Italy

Background: Despite the great evolution of endograft devices for thoracic endovascular aortic repair (TEVAR), threatening related complication such as graft migration and endoleaks still occur during follow up. The Drag Forces (DF), that is the displacement forces that play a role in graft migration and endoleaks caused by the blood flow against the thoracic graft, can be studied by means of Computational Fluid Dynamics (CFD). Method: A general review of papers found in current literature was performed. CFD studies available on the topic of thoracic aortic diseases and DF were analyzed. All anatomic, hemodynamics or graft related factors which could have an impact on DF were reported. Results: Different factors deeply influence DF magnitude in the different site of the Ishimaru's zones classification: angulation, tortuosity and length of the landing zone, graft diameter, length and deployment position, blood pressure, pulse waveform, blood viscosity and patient heart rate have been related to the magnitude of DF. Moreover, also the three-dimensional orientation of DF is emerging as a fundamental issue from CFD studies. DF can be divided in sideways and upward components. The former, even of higher magnitude in zone 0, maintain always an orthogonal orientation and does not change in any type of aortic arch;the latter result strictly related to the anatomic complexity of the aortic arch with values up to four times higher in zone 3. Conclusion: Different DF magnitude and orientation could explain how TEVAR have higher rate of migration and endoleaks when we face with more complex aortic anatomies. All these aspects should be foreseen during the planning of TEVAR procedure. In this field, collaboration between physicians and engineers is crucial, as both parts have a primary role in understanding and describing hidden aspects involved in TEVAR procedures.

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Laminated Solid Timber Slab with Transverse Prestressing Using the Strategy of Interleaved Vertical Displacement of Lamellae

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Journal of civil Engineering and architecture 2024年第4期18卷 186-198页

作者： Bianca Bispo dos Reis Jorge Daniel de Melo Moura Marcos Vinício de Camargo Everaldo Pletz Graduate Program in Architecture and Urbanism Londrina State UniversityJardim Portal de Versalhes 1Londrina 86057-970PRBrazil Department of Civil Engineering Federal Technological University of Paraná(UTFPR)Apucarana 86812-460PRBrazil Retired professor Department of Structural Engineering Londrina State UniversityLondrina 86057-970PRBrazil

This article presents a study on the structural behavior of transversely prestressed laminated timber slabs,focusing on an innovative approach:vertically misaligned *** misalignment,achieved by sliding vertically the wooden lamellae rather than aligning them,enhances the slab’s cross-section moment of inertia,thereby improving load-bearing capacity and *** involved two groups of structural size specimens:one with vertically aligned lamellae(control group)and the other with misaligned lamellae(study group).Results showed the study group exhibited 42%superior stiffness and 10%less load capacity compared to the *** typically occurred individually in the lamellae,particularly in those with defects or lower modulus of elasticity,concentrated in the middle third of the slabs’free span where tensile stresses *** a higher number of failed lamellae,the study group demonstrated promising *** of prestressing bar indicated no damage at all in the thread,suggesting potential for reducing bar *** findings offer crucial insights into applying these slabs in timber construction as well as to any kind of construction.

关键词： Transversal prestressed slabs wooden construction plantation wood flexural testing design methodology

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Prediction and Identification of Vulnerable Areas Due to Heavy Snowfall Using Machine Learning and K-Means Clustering with Rcp Scenarios

SSRN

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SSRN 2023年

作者： Song, Moon-Soo Yun, Hong-Sik Lee, Jae-Joon Yum, Sang-Guk Interdisciplinary Program in Crisis Disaster and Risk Management Sungkyunkwan University Suwon16419 Korea Republic of School of Civil Architectural Engineering & Landscape Architecture Sungkyunkwan University Suwon16419 Korea Republic of Department of Civil Engineering College of Engineering Gangneung-Wonju National University Gangneung25457 Korea Republic of

Heavy snowfall is a natural disaster that causes extensive damage in South Korea. Therefore, predicting heavy snowfall occurrence, identifying vulnerable areas, and establishing response plans to reduce risk are crucial. In this study, to predict heavy snowfall, meteorological, and geographic data from the past 30 years were collected, and four machine learning algorithms were trained and compared: multiple linear regression, support vector regression, random forest regressor (RFR), and extreme gradient boosting. We observed that the RFR model (R2 = 0.64) accurately predicted the occurrence of snowfall compared to other models. Representative concentration pathway (RCP) scenario data was input into the RFR model to generate prediction data up to 2100. Prediction results of more than 48.2 cm based on heavy snowfall events in the past 20 years were observed 17 times in RCP2.6, 19 times in RCP4.5, 16 times in RCP6.0, and 17 times in RCP8.5. Annual GIS-based snowfall images for the RCP8.5 scenario were classified using K-means clustering, grouped by vulnerable areas (Gangwon-do, Jeollabuk-do, northern Gyeonggi-do), and divided into five groups. Our study can aid decision-making on policies related to heavy snowfall disaster prevention standards, snow removal plans, budgeting, and the establishment of mid- to long-term climate change adaptation plans for government and public institutions. © 2023, The Authors. All rights reserved.

关键词： Machine learning

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