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Assessment Of Climate Change Impact On The Annual Maximum Flood In An Urban River In Dublin, Ireland, Arunima Sarkar Basu, Laurence William Gill, Francesco Pilla, Bidroha Basu Jan 2022

Assessment Of Climate Change Impact On The Annual Maximum Flood In An Urban River In Dublin, Ireland, Arunima Sarkar Basu, Laurence William Gill, Francesco Pilla, Bidroha Basu

Publications

Hydrological modelling to address the problem of flood risk corresponding to climate change can play an important role in water resources management. This paper describes the potential impact of climate change on an urban river catchment using a physically based hydrological model called Soil Water Assessment Tool (SWAT). The study area considered is the Dodder River basin located in the southern part of Dublin, the capital city of Ireland. Climate projections from three regional climate models and two representative concentration pathways (RPC 4.5 and RCP 8.5) were used to evaluate the impact of flooding corresponding to different climate change scenarios. …


On-Site Analyses As A Decision Support Tool For Dredging And Sustainable Sediment Management, Bruno Lemière, Valérie Laperche, Arjan Wijdeveld, Marco Wensveen, Richard Lord, Alasdair Hamilton, Laurence Haouche, Mathieu Henry, Joe Harrington, Branislav Batel, Pascal Lehette Jan 2022

On-Site Analyses As A Decision Support Tool For Dredging And Sustainable Sediment Management, Bruno Lemière, Valérie Laperche, Arjan Wijdeveld, Marco Wensveen, Richard Lord, Alasdair Hamilton, Laurence Haouche, Mathieu Henry, Joe Harrington, Branislav Batel, Pascal Lehette

Publications

Beneficial use of dredged sediments, either in harbours or waterways, is based on their potential as alternative resources. Such sediments can be considered as bulk materials for industrial needs, which is predicated on their current waste status or meeting end-of-waste constraints. They also can be an integral part of beneficial use projects using sediments as a bulk component, including civil engineering and landscaping. This is particularly important for beneficial use projects focusing on climate change effects mitigation, such as flood protection works, coastline defence or littoral urban areas redevelopment. When dredged sediment is used as a bulk material, its acceptability …


Maximum Profit Facility Location And Dynamic Resource Allocation For Instant Delivery Logistics, Darshan Chauhan, Avinash Unnikrishnan, Stephen D. Boyles Jan 2022

Maximum Profit Facility Location And Dynamic Resource Allocation For Instant Delivery Logistics, Darshan Chauhan, Avinash Unnikrishnan, Stephen D. Boyles

Civil and Environmental Engineering Faculty Publications and Presentations

Increasing e-commerce activity, competition for shorter delivery times, and innovations in transportation technologies have pushed the industry toward instant delivery logistics. This paper studies a facility location and online demand allocation problem applicable to a logistics company expanding to offer instant delivery service using unmanned aerial vehicles or drones. The problem is decomposed into two stages. During the planning stage, the facilities are located, and product and battery capacity are allocated. During the operational stage, customers place orders dynamically and real-time demand allocation decisions are made. The paper explores a multi-armed bandit framework for maximizing the cumulative reward realized by …


Highway Stormwater Runoff On-Site Treatment Using Bioslope With New Media Of Biochar Amended Topsoils, Ahmed I. Yunus Jan 2022

Highway Stormwater Runoff On-Site Treatment Using Bioslope With New Media Of Biochar Amended Topsoils, Ahmed I. Yunus

College of Graduate Studies: Theses & Dissertations

Georgia Department of Transportation (GDOT) has constructed various treatment facilities on its right-of-way (ROW) to collect and treat highway stormwater runoff, emphasizing total suspended solids (TSS) removal. The permit performance goal set by the Georgia Environmental Protection Division (EPD) is 80% TSS removal. Current stormwater best management practice (BMP) treatment facilities include complex and permanent infrastructures such as bioslope, bioretention basins, sand filters, infiltration trenches, and grass channels. Among these BMPs, bioslope has been becoming more popular due to its applicability for roadway embankments and areas with limited ROW constraints. It removes pollutants effectively by physical filtration and chemical adsorption …


Analysis Of Spatial Discrepancies Between 76-Foot Close Range Photogrammetric And Terrestrial-Lidar Models, Abdoul K. Ouangre Jan 2022

Analysis Of Spatial Discrepancies Between 76-Foot Close Range Photogrammetric And Terrestrial-Lidar Models, Abdoul K. Ouangre

College of Graduate Studies: Theses & Dissertations

This study presents an analysis of the accuracy of a 3D model generated by two different methods. In the first method, the 3D model is generated via Laser Scanning. In the second method, the 3D model is generated via Close-range Photogrammetry from a drone flying at 76 feet above the ground. Photogrammetry is a photo-based technique that uses images to generate 3D models of objects where distances could be extracted from. Close-range photogrammetry is the approach of generating a 3D model from a camera placed anywhere between 1 foot and 1000 feet relative to the object. Terrestrial LiDAR is the …


Surrogate-Assisted Machine Learning Method For Reliability-Based Continuum Topology Optimization, Thu Van Huynh Jan 2022

Surrogate-Assisted Machine Learning Method For Reliability-Based Continuum Topology Optimization, Thu Van Huynh

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis proposes an efficient reliability-based topology optimization (RBTO) method that advantageously decouples cross-entropy (CE) method with Gaussian process regression (GPR) model, termed as CE-GPR. The method iteratively performs the bi-directional evolutionary structural optimization (BESO) with deterministic parameters based on the most probable point (MPP) underpinning limit-state functions iteratively updated by the active learning reliability evaluation process. The GPR model approximates the spectrum of LSFs under random parameters, and hence enables a low-cost CE method for failure probability approximation. The expected feasibility function (EFF) is maximized using the CLPSO to systematically refine the GPR model by adding new (intelligent) learning …


Towards An Artificial Intelligence Based Decision Support System To Evaluate Various Transit Projects, Patricio F. Vicuna Jan 2022

Towards An Artificial Intelligence Based Decision Support System To Evaluate Various Transit Projects, Patricio F. Vicuna

Dissertations and Theses

This dissertation addressed a subset of the Transit Network Design Problem (Transit-NDP), where the main evaluation parameter is the impact of various transit projects – Bus Lines, Tram, Light Rail, Rail – on the Network Travel Time (NTT) of the vehicles. The NTT is estimated using the static four-step travel demand model (trip generation, trip distribution, modal split, and traffic assignment). A set of five metaheuristic models were developed and implemented for this specific Transit-NDP, namely, Simulated Annealing (SA)-VISUM, Simulated Annealing-Random Forest Regression Model (SA-RF), Tabu Search (TS)-Random Forest (TS-RF), SA-RF-TS-VISUM, SA-RF-VISUM. These models were evaluated using two test networks …


Evaluation Of Snow And Streamflow In The National Water Model With Analysis Using Machine Learning, Engela Sthapit Jan 2022

Evaluation Of Snow And Streamflow In The National Water Model With Analysis Using Machine Learning, Engela Sthapit

Dissertations and Theses

Snow has great influence on land-atmosphere interactions and snowmelt from the mountains is a vital water source for downstream communities dependent on snow fed lakes, rivers and streams. This study explored the snow and streamflow prediction capabilities of process-based numerical prediction and data-driven machine learning models.

The overall goal of this study was to understand the deficiencies in the NOAA’s National Water Model (NWM) to represent snow, subsequently streamflow, and recognize the areas where it could be improved for future model developments. The goal was also to evaluate if the recent advancements in machine learning techniques is useful for predicting …


Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi Jan 2022

Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi

Dissertations and Theses

There has been a recent evolvement in the field of remote sensing after increase of number satellites and sensors data which could be fused to produce new data and products. These efforts are mainly focused on using of simultaneous observations from different platforms with different spatial and temporal resolutions. The research dissertation aims to enhance the synergy use of active and passive microwave observations and examine the results in detection land freeze and thaw (FT) predictions. Freeze thaw cycles particularly in high-latitude regions have a crucial role in many applications such as agriculture, biogeochemical transitions, hydrology and ecosystem studies. The …


A Citizen-Science Approach For Urban Flood Risk Analysis Using Data Science And Machine Learning, Candace Agonafir Jan 2022

A Citizen-Science Approach For Urban Flood Risk Analysis Using Data Science And Machine Learning, Candace Agonafir

Dissertations and Theses

Street flooding is problematic in urban areas, where impervious surfaces, such as concrete, brick, and asphalt prevail, impeding the infiltration of water into the ground. During rain events, water ponds and rise to levels that cause considerable economic damage and physical harm. The main goal of this dissertation is to develop novel approaches toward the comprehension of urban flood risk using data science techniques on crowd-sourced data. This is accomplished by developing a series of data-driven models to identify flood factors of significance and localized areas of flood vulnerability in New York City (NYC). First, the infrastructural (catch basin clogs, …


Towards Simulation Of Complex Ocean Flows: Analysis And Algorithm For Computation Of Coupled Partial Differential Equations, Wenbin Dong Jan 2022

Towards Simulation Of Complex Ocean Flows: Analysis And Algorithm For Computation Of Coupled Partial Differential Equations, Wenbin Dong

Dissertations and Theses

The hybrid CFD models which usually consist of 2 sub-models, develop our capability to simulate many emerging problems with multiphysics and multiscale flows, especially for the coastal ocean flows interacted with local phenomena of interest. For most cases, the sub-models are connected with direct interpolation which is easy and workable. It becomes urgently needed to investigate the inner mechanism of such model integration as this simple method does not work well if the two sub-models are different in governing equations, numerical methods, and computational grids. Also, it can not treat complex flow structures as well as the balance in mass …


การออกแบบขนาดและรูปร่างของโครงถักสามมิติอย่างเหมาะสม ด้วยวิธีการปรับปรุงการเรียนรู้อย่างครอบคลุมเพื่อหาค่าเหมาะสมที่สุดของกลุ่มอนุภาคร่วมกับแบบจำลองการถดถอยของกระบวนการเกาส์เซียน, วรัญญา เจริญยิ่ง Jan 2022

การออกแบบขนาดและรูปร่างของโครงถักสามมิติอย่างเหมาะสม ด้วยวิธีการปรับปรุงการเรียนรู้อย่างครอบคลุมเพื่อหาค่าเหมาะสมที่สุดของกลุ่มอนุภาคร่วมกับแบบจำลองการถดถอยของกระบวนการเกาส์เซียน, วรัญญา เจริญยิ่ง

Chulalongkorn University Theses and Dissertations (Chula ETD)

บทความนี้นำเสนอหนึ่งในเครื่องมือการเรียนรู้ของเครื่อง คือวิธีการถดถอยของกระบวนการเกาส์เซียน (Gaussian process regression, GPR) ร่วมกับอัลกอริทึมการปรับปรุงการเรียนรู้อย่างครอบคลุมเพื่อหาค่าเหมาะสมที่สุดของกลุ่มอนุภาค (Enhanced Comprehensive Learning Particle Swarm Optimization, ECLPSO) เพื่อหาขนาดและรูปร่างที่เหมาะสมอย่างพร้อมกันของโครงถัก 3 มิติ ภายใต้แรงกระทำจากภายนอก เมื่อเทียบกับเทคนิคการออกแบบด้วยวิธีเมตา-ฮิวริสติก แนวทางนี้จะสามารถลดขั้นตอนในการวิเคราะห์โครงสร้างด้วยระเบียบวิธีไฟไนต์เอลิเมนต์ที่ใช้เวลานานได้ โดยเป็นการสร้างแบบจำลองการทำนายพฤติกรรมของโครงสร้าง จากชุดข้อมูลอินพุต เช่น ตำแหน่งพิกัดข้อต่อและขนาดชิ้นส่วน และข้อมูลเอาต์พุตที่สร้างโดยชุดข้อมูลการวิเคราะห์โครงสร้าง เช่น แรงภายในชิ้นส่วนและการเคลื่อนที่ของตำแหน่งข้อต่อ จากนั้นอัลกอริทึม ECLPSO จะดำเนินการร่วมกับแบบจำลอง GPR ที่มีการคาดคะเนการตอบสนองที่แม่นยำเพียงพอ ผลลัพธ์ที่ได้จากวิธีการที่นำเสนอ คือน้ำหนักรวมของโครงสร้างที่มีค่าต่ำที่สุด ซึ่งแสดงให้เห็นถึงความแม่นยำและประสิทธิภาพของอัลกอริทึม


An Analytical Network Process (Anp) Model For Choosing Optimal Public-Private Partnership (Ppp) Contract Types For Infrastructure Projects, Su Lae Yee Zaw Jan 2022

An Analytical Network Process (Anp) Model For Choosing Optimal Public-Private Partnership (Ppp) Contract Types For Infrastructure Projects, Su Lae Yee Zaw

Chulalongkorn University Theses and Dissertations (Chula ETD)

With the rapid social and economic development, a great deal of expenditure is crucial for the nation's infrastructure development. Nevertheless, the governments of many developing nations have been experienced with the limited budget and technical inability to deliver effective public infrastructures. Public-private partnership (PPP) has been adopted as an alternative collaboration arrangement between the government and the private sector in many nations to overcome these challenges. PPP can be defined as a long-term contract between a public agency and a private entity for rendering public facilities, including design, construct, finance, operate, and manage the project. The PPP contract types can …


Cive 440: Reinforced Concrete Design I: Faculty-Led Inquiry Into Reflective And Scholarly Teaching (First) Course Portfolio, Chungwook Sim Jan 2022

Cive 440: Reinforced Concrete Design I: Faculty-Led Inquiry Into Reflective And Scholarly Teaching (First) Course Portfolio, Chungwook Sim

UNL Faculty Course Portfolios

This Faculty-led Inquiry into Reflective and Scholarly Teaching (FIRST) Course Portfolio documents the instructor’s teaching practices and student learning for Reinforced Concrete Design I (CIVE 440) course. The contents of this course portfolio captures the CIVE 440 course that was taught on the Lincoln campus during the semester of Fall 2022. CIVE 440 is a structural engineering design elective offered every year in the Department of Civil and Environmental Engineering on both Lincoln and Omaha campus at University of Nebraska-Lincoln (UNL). The course objective is to help students to be able to use theory and experience to proportion and detail …


Fish And Invertebrate Use Of Restored Vs. Natural Oyster Reefs In A Shallow Temperate Latitude Estuary, Jonathan H. Grabowski, Christopher J. Baillie, Adam Baukus, Rachael Carlyle, F. Joel Fodrie, Rachel K. Gittman, A. Randall Hughes, David L. Kimbro, Juhyung Lee, Hunter S. Lenihan, Sean P. Powers, Kevin Sullivan Jan 2022

Fish And Invertebrate Use Of Restored Vs. Natural Oyster Reefs In A Shallow Temperate Latitude Estuary, Jonathan H. Grabowski, Christopher J. Baillie, Adam Baukus, Rachael Carlyle, F. Joel Fodrie, Rachel K. Gittman, A. Randall Hughes, David L. Kimbro, Juhyung Lee, Hunter S. Lenihan, Sean P. Powers, Kevin Sullivan

University Faculty and Staff Publications

Coastal marine habitats continue to be degraded, thereby compelling largescale restoration in many parts of the world. Whether restored habitats function similarly to natural habitats and fully recover lost ecosystem services is unclear. In estuaries, oyster reefs have been degraded by multiple anthropogenic activities including destructive fishing practices and reduced water quality, motivating restoration to maintain oyster fisheries and other ecosystem services, often at relatively high cost. We compared fish and invertebrate communities on recently restored (0–1 year post-restoration), older restored (3–4 years post-restoration), and natural oyster reefs to determine if and when restored reefs support functionally similar faunal communities. …


Air Passenger Demand Forecast Through The Use Of Artificial Neural Network Algorithms, Juan Gerardo Muros Anguita, Oscar Díaz Olariaga Jan 2022

Air Passenger Demand Forecast Through The Use Of Artificial Neural Network Algorithms, Juan Gerardo Muros Anguita, Oscar Díaz Olariaga

International Journal of Aviation, Aeronautics, and Aerospace

Airport planning depends to a large extent on the levels of activity that are anticipated. In order to plan facilities and infrastructures of an airport system and to be able to satisfy future needs, it is essential to predict the level and distribution of demand. This document presents a short- and medium-term forecast of the demand for air passengers carried out through a specific case study (Colombia), in which the impact of the pandemic period due to COVID-19 on air traffic was taken into account. To make the forecast, an algorithm that implements techniques based on Artificial Neural Networks (ANN) …


Dynamic Modeling Of Inland Flooding And Storm Surge On Coastal Cities Under Climate Change Scenarios: Transportation Infrastructure Impacts In Norfolk, Virginia Usa As A Case Study, Yawen Shen, Navid Tahvildari, Mohamed M. Morsy, Chris Huxley, T. Donna Chen, Jonathan Lee Goodall Jan 2022

Dynamic Modeling Of Inland Flooding And Storm Surge On Coastal Cities Under Climate Change Scenarios: Transportation Infrastructure Impacts In Norfolk, Virginia Usa As A Case Study, Yawen Shen, Navid Tahvildari, Mohamed M. Morsy, Chris Huxley, T. Donna Chen, Jonathan Lee Goodall

Civil & Environmental Engineering Faculty Publications

Low-lying coastal cities across the world are vulnerable to the combined impact of rainfall and storm tide. However, existing approaches lack the ability to model the combined effect of these flood mechanisms, especially under climate change and sea level rise (SLR). Thus, to increase flood resilience of coastal cities, modeling techniques to improve the understanding and prediction of the combined effect of these flood hazards are critical. To address this need, this study presents a modeling system for assessing the combined flood impact on coastal cities under selected future climate scenarios that leverages ocean modeling with land surface modeling capable …


Cal Poly Construction Management Summer Bootcamp 2022, Mason A. Heinse Jan 2022

Cal Poly Construction Management Summer Bootcamp 2022, Mason A. Heinse

Construction Management

The purpose of this paper is to outline the intent and key objectives of the Cal Poly Construction Management Summer Bootcamp. This project was developed through collaboration with Cal Poly Construction Management faculty and other contributors to create a multi-scope project with the objective of creating a summer bootcamp. The camp was proposed to assist the San Luis Obispo County Office of Education and the Central Coast Homebuilders Association with promoting skilled trades education in high schools. Local high schools currently implement the Building Industry Technology Academy (BITA) curriculum, which has proven difficult for students to enroll in or complete. …


Optimizing Exterior Lighting Illuminance And Spectrum For Human, Environmental, And Economic Factors., S. M. Simmons, Stuart Werner Baur, William L. Gillis, Devin Michael Burns, Heath Pickerill Jan 2022

Optimizing Exterior Lighting Illuminance And Spectrum For Human, Environmental, And Economic Factors., S. M. Simmons, Stuart Werner Baur, William L. Gillis, Devin Michael Burns, Heath Pickerill

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

With the recent widespread adoption of LED lighting in outdoor areas, numerous concerns have been raised about the potential for harmful effects on humans, animals, plants, and the night sky. These stem from the high blue light content of some LED bulbs and an incentive to increase lighting levels caused by higher efficiency and lower costs. While new lighting installations are often described as environmentally friendly due to their energy efficiency, factors such as light pollution are often neglected or not given enough weight. This research focuses on optimizing the design of exterior lighting for human, environmental, and economic factors …


Fan-Shaped Model For Generating The Anisotropic Catchment Area Of Subway Stations Based On Feeder Taxi Trips, Shiwei Liu, Yajuan Deng, Xianbiao Hu, Jiaxing Zhou, Jianming Chen Jan 2022

Fan-Shaped Model For Generating The Anisotropic Catchment Area Of Subway Stations Based On Feeder Taxi Trips, Shiwei Liu, Yajuan Deng, Xianbiao Hu, Jiaxing Zhou, Jianming Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The catchment areas of subway stations have always been considered as a circular shape in previous research. Although some studies show the catchment area may be affected by road conditions, public transportation, land use, and other factors, few studies have discussed the shape of the catchment area. This study focuses on analyzing the anisotropy of catchment areas and developing a sound methodology to generate them. Based on taxi global positioning system (GPS) data, this paper first proposes a data mining method to identify feeder taxi trips around subway stations. Then, a fan-shaped model is proposed and applied to Xi'an Metro …


Bcmnet: Cross-Layer Extraction Structure And Multiscale Downsampling Network With Bidirectional Transpose Fpn For Fast Detection Of Wildfire Smoke, Jiayong Li, Guoxiong Zhou, Aibin Chen, Chao Lu, Liujun Li Jan 2022

Bcmnet: Cross-Layer Extraction Structure And Multiscale Downsampling Network With Bidirectional Transpose Fpn For Fast Detection Of Wildfire Smoke, Jiayong Li, Guoxiong Zhou, Aibin Chen, Chao Lu, Liujun Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

At present, the wildfire smoke detection algorithm based on YOLOv3 has problems, such as low accuracy and slow detection speed. In this article, we propose a cross-layer extraction structure and multiscale downsampling network with bidirectional transpose FPN (BCMNet) for fast detection of wildfire smoke. First, a cross-layer extraction module, which combines linear feature multiplexing and receptive field amplification, is designed. It can improve the speed and accuracy of wildfire smoke detection. Second, a multiscale downsampling module with different convolution kernels and maximum pooling operation is designed to preserve the details of the image while downsampling. Then, a bidirectional transposed FPN …


Definition And Detection Of Hypervulnerabilities Using A Framework For Assessing Port Resilience, Katherine Smith, Rafael Diaz, Yuzhong Shen, Francesco Longo Jan 2022

Definition And Detection Of Hypervulnerabilities Using A Framework For Assessing Port Resilience, Katherine Smith, Rafael Diaz, Yuzhong Shen, Francesco Longo

VMASC Publications

Long term plans for maritime ports are identifying investments that will increase their capacity while decreasing their environmental footprint and operating costs. These changes are leading to increases in complexity at a time when leaner practices are driving investments to become more strategic. As such, this work proposes a generalized definition that allows a system or entity to be classified as exceedingly vulnerable by comparing it to other entities. This definition is developed from a set of definitions gathered from disparate fields. From this definition grounded in theory, the initial rules for complex system implementation are developed and demonstrated on …


Methodology To Treat Bottom Friction Losses For Modeling Wave Transformation From Deepwater To The Nearshore: An Application In Northeast Florida, Oscar Solisromero Jan 2022

Methodology To Treat Bottom Friction Losses For Modeling Wave Transformation From Deepwater To The Nearshore: An Application In Northeast Florida, Oscar Solisromero

UNF Graduate Theses and Dissertations

Designers and other practitioners confront a wide range of problems in the coastal zone, which often require long-term nearshore wave data. However, such data are usually quite scarce. Consequently, either wave measurements from buoys deployed in deep water, or archived deepwater wave hindcast information, must be utilized by rigorous, physics-based transformation to the site of interest using one of many available numerical models. A main issue in conducting such an effort is accounting for losses in wave energy due to bottom friction, for which establishing a suitable bed friction coefficient (Cf) can be problematic. In the present study, …


Maximum Likelihood Estimator Method To Estimate Flaw Parameters For Different Glass Types, Nabhajit Goswami Jan 2022

Maximum Likelihood Estimator Method To Estimate Flaw Parameters For Different Glass Types, Nabhajit Goswami

Dissertations, Master's Theses and Master's Reports

Glass is commonly used in architectural applications, such as windows and in-fill panels and structural applications, such as beams and staircases. Despite the popularity of structural glass use in buildings, an engineering design standard to determine the required component or member strength for design loads does not exist. Glass is a brittle material that lacks a well-defined yield or ultimate stress, unlike ductile materials. The traditional engineering methods used to design a ductile material cannot be used to design a glass component. Glass fails in tension primarily due to the presence of microscopic flaws present on the surface that acts …


Kinematics And Preliminary Fema P-695 Evaluation Of The Newz-Breakss Steel Boundary Frame With Buckling Restrained Brace Structural Fuses, Alexander M. Baker Jan 2022

Kinematics And Preliminary Fema P-695 Evaluation Of The Newz-Breakss Steel Boundary Frame With Buckling Restrained Brace Structural Fuses, Alexander M. Baker

Dissertations, Master's Theses and Master's Reports

Buckling Restrained Braced Frames (BRBFs) have become a popular seismic force resisting system (SFRS) due to their high ductility and energy dissipation. However, BRBFs are also susceptible to large residual drifts, which can make repair difficult. Efforts to reduce the residual drift of BRBFs typically involve special self-centering braces, or by using a dual system in tandem with the BRBF. This study proposes an alternative approach, in which a self-centering steel rocking frame is used as the boundary frame for the BRBF. The proposed system, called the NewZ-BREAKSS Buckling Restrained Braced Frame (NZ-BRBF) utilizes the recently proposed NewZ-BREAKSS (NZ) boundary …


A Three-Dimensional Fully Coupled Hydro-Mechanical Elasto-Plastic Model For Unsaturated Soils With Consideration Of Hysteresis Behavior, Beshoy Sami Moussa Riad Jan 2022

A Three-Dimensional Fully Coupled Hydro-Mechanical Elasto-Plastic Model For Unsaturated Soils With Consideration Of Hysteresis Behavior, Beshoy Sami Moussa Riad

Doctoral Dissertations

"Unsaturated soils are often used as a construction material in transportation infrastructures; in which it is subjected to cyclic traffic loadings and/or seasonal wetting-drying cycles. While mechanical hysteresis is a common feature of soils in general, hydraulic hysteresis is associated with unsaturated soils. Most existing constitutive models paid limited attention to the mechanical and hydraulic hysteresis behavior of unsaturated soils. This research presents a three-dimensional model for unsaturated soils and a chemo mechanical model for saturated soils. The unsaturated soils’ model has the following characteristic features: (a) the hydraulic and mechanical behaviors are fully coupled under 3D conditions; (b) it …


Use Of Cellular Concrete For Air Convection Embankment To Protect Permafrost Foundation In Cold Regions, Hanli Wu Jan 2022

Use Of Cellular Concrete For Air Convection Embankment To Protect Permafrost Foundation In Cold Regions, Hanli Wu

Doctoral Dissertations

"Crushed-rock air convection embankment (ACE) has been used to mitigate thaw settlement, and pavement distresses caused by climatic extremes in permafrost regions for over three decades. However, the desired crushed rocks needed for ACE are not readily available in many areas of interior Alaska. Burdened by the need to ship suitable rocks to remote locations, the cost of constructing an ACE is often prohibitively high, which prevents its wide use in Alaska. An existing cementitious material, cellular concrete, may provide the solution.

This study intends to systematically characterize the heat transfer patterns of ACE and identify the performance benefits of …


Automatic Image-Based Sbfe Approach For Multiphase-Materials Topology Optimization Under Dynamic Loading, Rut Su Jan 2022

Automatic Image-Based Sbfe Approach For Multiphase-Materials Topology Optimization Under Dynamic Loading, Rut Su

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis presents the efficient topology optimization methods constructed within the state-of-the-art polygon scaled boundary finite element (SBFE) framework. The SBFE approach enables the discrete model construction of structures comprising of arbitrary curve geometry lying in 2D and/or 3D spaces. More explicitly, incorporated with quadtree (in 2D) and octree (3D) mesh refinements the automatic adaptive mesh scheme run within the polygon SBFE framework provides the cost-effective model generation allowing hanging nodes. These distinctive features present the developed SBFE approach well suiting as an underlying modeling framework for the topology design optimization of solids. The bi-directional evolutionary structural optimization (BESO) algorithm …


Source Apportionment Of Fine Particulate Matter Down To Nanoparticle In Bangkok By Positive Matrix Factorization (Pmf) Model, Thanaphum Manjantrarat Jan 2022

Source Apportionment Of Fine Particulate Matter Down To Nanoparticle In Bangkok By Positive Matrix Factorization (Pmf) Model, Thanaphum Manjantrarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research study investigated the sources of particulate matter with sizes ranging from less than 0.1 to larger than 10 microns in Bangkok by installing Nanosampler at three measurement stations (Ari, Din Daeng, and Bang Na) for one year (January 2021-December 2021). The collected samples were analyzed for ion species, carbon species, and elemental components to identify the chemical composition. The results were then used to classify the sources of air pollution using the Positive Matrix Factorization (PMF) model. The study indicated that particulate matter levels are highest from December to March and lowest from April to November. The average …


Assessment Of Emissions From Cement Plants Using Aermod Modeling, Atef I. Abdel-Gawad, Mahmoud Noureldeen, Hamada Mahmaoud, Asmaa S. Hamouda Jan 2022

Assessment Of Emissions From Cement Plants Using Aermod Modeling, Atef I. Abdel-Gawad, Mahmoud Noureldeen, Hamada Mahmaoud, Asmaa S. Hamouda

Applied Environmental Research

Coal combustion generates many gases and emissions which are harmful to public health and the environment. So, it is necessary to assess the health risks for the people living in the nearby cement plants that use coal as a fuel. In this article, a health risk assessment HRA was carried out concerning the air emissions from a cement plant in the heavy industry area located at Beni Suef governorate - Egypt. The article handles the assessment of the health risks for pollutants classified as non-carcinogenic i.e. sulfur dioxide - mercury and the health risks for pollutants classified as carcinogenic i.e. …