Engineering Commons^™

Multi-Factor Optimization Of Bio-Methanol Production Through Gasification Process Via Statistical Methodology Coupled With Genetic Algorithm, Amin Hedayati Moghaddam, Morteza Esfandyari, Dariush Jafari, Hossein Sakhaeinia

Department of Civil and Environmental Engineering: Faculty Publications

This work innovatively explores the bio-methanol production process, conducts comprehensive analyses, develops statistical models, and optimizes operational conditions, contributing valuable insights to the field of sustainable energy production from biomass. Accordingly, bio-methanol production from biomass through gasification route was investigated and simulated using Aspen Plus software. The effects of operational parameters on energy duty of gasification reactor and the methanol production rate in syngas to methanol reactor were investigated. The parameters affecting the process performance including temperature, pressure, and steam/feed ratio were examined using the response surface methodology (RSM) by central composite design (CCD) technique. Analysis of variance (ANOVA) was …

Multi-Factor Optimization Of Bio-Methanol Production Through Gasification Process Via Statistical Methodology Coupled With Genetic Algorithm, Amin Hedayati Moghaddam, Morteza Esfandyari, Dariush Jafari, Hossein Sakhaeinia

Department of Civil and Environmental Engineering: Faculty Publications

This work innovatively explores the bio-methanol production process, conducts comprehensive analyses, develops statistical models, and optimizes operational conditions, contributing valuable insights to the field of sustainable energy production from biomass. Accordingly, bio-methanol production from biomass through gasification route was investigated and simulated using Aspen Plus software. The effects of operational parameters on energy duty of gasification reactor and the methanol production rate in syngas to methanol reactor were investigated. The parameters affecting the process performance including temperature, pressure, and steam/feed ratio were examined using the response surface methodology (RSM) by central composite design (CCD) technique. Analysis of variance (ANOVA) was …

Applications Of Agent-Based Modeling (Abm) In Enhancing Facility Operation And Management, Ali Khodabandelu, Jee Woong Park

Civil and Environmental Engineering and Construction Faculty Research

Agent-based modeling (ABM), as a relatively new simulation technique, has recently gained in popularity in the civil engineering domain due to its uniquely advantageous features. Among many civil engineering applications, ABM has been applied to facility operation and management, such as energy consumption management, as well as the enhancement of maintenance and repair processes. The former studies used ABM to manage energy consumption through simulating human energy-related behaviors and their interactions with facilities, as well as electrical, heating, and cooling systems and appliances, while the latter used ABM to enhance maintenance process through facilitating coordination, negotiation, and decision making between …

An Agent-Based Framework For Investigating Safety-Productivity Tradeoff Of Construction Laborers Considering Risk-Taking Behavioral Heterogeneity, Ali Khodabandelu, Jee Woong Park, Seyedmohsen Kheyrandish

Civil and Environmental Engineering and Construction Faculty Research

Construction laborers and crews play a critical role in achieving a safe and productive construction site. Many past research studies used top-down approaches/perspectives for studying the impact of laborers' performance on overall construction site outputs with limited flexibility in accounting for laborers' various characteristics. However, the recent reap in computational advances allowed applications of bottom-up architectures, which can potentially incorporate heterogeneous characteristics of laborers' individual behavioral and decision-making features effectively. Accordingly, agent-based modeling (ABM), as a tool to leverage a bottom-up methodological approach, has been widely adopted by recent research. Existing literature investigated the influence of changes in laborers' behaviors …

Integration Of Material Characterization, Thermoforming Simulation, And As-Formed Structural Analysis For Thermoplastic Composites, Philip M. Bean, Roberto A. Lopez-Anido, Senthil Vel

Civil Engineering Faculty Scholarship

An improved simulation-based thermoforming design process based on the integration of material characterization and as-formed structural analysis is proposed. The tendency of thermoplastic composites to wrinkle during forming has made simulation critical to optimized manufacturing, but the material models required are complex and time consuming to create. A suite of experimental methods has been developed for measurement of several required properties of the molten thermoplastic composite. These methods have the potential to enhance thermoplastic composites manufacturing by simplifying and expediting the process. These material properties have been verified by application to thermomechanical forming predictions using commercial simulation software. The forming …

Enhancing Serviceability And Resiliency Of Transportation Networks Based On Topological Credentials And Systematic Design Interventions, Md Ashraf Ahmed

FIU Electronic Theses and Dissertations

Recent advancements in network science showed that the topological credentials (i.e., rank of relative importance) of network components (such as nodes and links), carry significant implications as it is critical to know which components contribute the most to the overall network performance. For transportation networks, critical components (roads, bridges) may become inaccessible for adjacent traffic due to day-to-day congestion or external disruptions (i.e., man-made or natural hazards) that significantly reduce the level of service. Hence, topological credentials of critical network components based on their connectivity need to be assessed to enhance the serviceability, i.e., improved travel time experience as well …

Energy Harvesting For Self-Powered Sensors For Smart Transportation Infrastructures, Anil K. Agrawal, Mohsen Amjadian, Hani Nassif

Civil Engineering Faculty Publications and Presentations

In this research project, an Electromagnetic Energy Harvesting System (EMEHS) is developed for harvesting the kinetic energy of ambient and traffic-induced vibrations and carry out a detailed feasibility study and impacts of such system for application on transportation infrastructures. The proposed EMEHS utilizes the innovative concept of creating array of large number of small permanent magnets through certain optimization criteria to achieve strong and focused magnetic field in a particular orientation. When these magnets are attached to a flexible sub-system and placed close to the copper coil, ambient and traffic-induced vibration of the sub-system induces eddy current in copper the …

Network Modeling Of Hurricane Evacuation Using Data-Driven Demand And Incident-Induced Capacity Loss Models, Yuan Zhu, Kaan Ozbay, Kun Xie, Hong Yang, Ender Foruk Morgul

Civil & Environmental Engineering Faculty Publications

The development of a hurricane evacuation simulation model is a crucial task in emergency management and planning. Two major issues affect the reliability of an evacuation model: one is estimations of evacuation traffic based on socioeconomic characteristics, and the other is capacity change and its influence on evacuation outcome due to traffic incidents in the context of hurricanes. Both issues can impact the effectiveness of emergency planning in terms of evacuation order issuance, and evacuation route planning. The proposed research aims to investigate the demand and supply modeling in the context of hurricane evacuations. This methodology created three scenarios for …

Safety Considerations For All Road Users On Edge Lane Roads, Michael Williams, Marcial Lamera, Aleksander Bauranov, Carole Voulgaris, Anurag Pande

Mineta Transportation Institute

Edge lane roads (ELRs), also known as advisory bike lanes or advisory shoulders, are a type of shared street where two-way motor vehicle (MV) traffic shares a single center lane, and edge lanes on either side are preferentially reserved for vulnerable road users (VRUs). This work comprises a literature review, an investigation of ELRs’ operational characteristics and potential road user interactions via simulation, and a study of crash data from existing American and Australian ELRs.

The simulation evaluated the impact of various factors (e.g., speed, volume, directional split, etc.) on ELR operation. Results lay the foundation for a siting criterion. …

Modeling Operational Performance Of Urban Roads With Heterogeneous Traffic Conditions, Swapneel R. Kodupuganti, Sonu Mathew, Srinivas S. Pulugurtha

Mineta Transportation Institute

The rapid growth in population and related demand for travel during the past few decades has had a catalytic effect on traffic congestion, air quality, and safety in many urban areas. Transportation managers and planners have planned for new facilities to cater to the needs of users of alternative modes of transportation (e.g., public transportation, walking, and bicycling) over the next decade. However, there are no widely accepted methods, nor there is enough evidence to justify whether such plans are instrumental in improving mobility of the transportation system. Therefore, this project researches the operational performance of urban roads with heterogeneous …

An Agent-Based Model To Study Competitive Construction Bidding And The Winner's Curse, Amr Elsayegh, Cihan H. Dagli, Islam H. El-Adaway

Engineering Management and Systems Engineering Faculty Research & Creative Works

Reverse auction theory is the basis for competitive construction bidding process. The lowest bid method is utilized for selecting contractors in public projects. The winning contractor having the lowest bid value could be cursed when the submitted bid value results in negative profits. This is caused by many factors such as the contractor's estimation accuracy and markup. This is addressed in this paper by providing a model simulating the construction competitive bidding and the occurrence of the winner's curse. To this end, the authors show the extent to which the winner's curse affects the status of contracting companies. The objectives …

Mechanism Of Tricalcium Silicate Hydration In The Presence Of Polycarboxylate Polymers, Rachel Cook, Hongyan Ma, Aditya Kumar

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Abstract: The early-age hydration of cement is inhibited in the presence of comb-shaped polycarboxylate ether (PCE) polymer -- a dispersant commonly added to control rheological properties of fresh cement paste. This study employs a series of microcalorimetry experiments and phase boundary nucleation and growth simulations to elucidate the effects of dosage and molecular architecture of PCE on hydration of tricalcium silicate (Ca₃SiO₅ or C₃S in cement notation), the dominant phase in cement. Results show that PCE -- regardless of its molecular architecture -- suppresses early-age hydration of C₃S. PCE-induced retardation becomes increasingly more …

Effects Of Moving Bottlenecks On Traffic Operations On Four-Lane Level Freeway Segments, Jianan Zhou

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The Highway Capacity Manual (HCM) was developed to provide capacity and level of service analyses for roadway facilities. Trucks may adversely affect the quality of traffic flow on a roadway. In HCM, the passenger car equivalent (PCE) of a truck, which represents the number of passenger cars that have an equivalent effect on traffic flow, is used to account for the impacts of trucks. However, in the past ten years rural freeways in the western rural U.S. have experienced conditions that lie outside the standard HCM conditions. Also, the current HCM truck PCEs may not be appropriate for the western …

Development Of Iowa Dot Combination Bridge Separation Barrier With Bicycle Railing, Chaz M. Ginger

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

The Iowa Department of Transportation typically builds separation barriers between vehicle and pedestrian/bicycle facilities when sidewalks or trails are present on vehicular bridges. Currently, Iowa DOT employs a combination bridge rail that utilizes a concrete parapet that previously had been successfully evaluated to National Cooperative Highway Research Program (NCHRP) Report 350 Test Level 4 (TL-4) criteria for these situations. While the parapet had been successfully evaluated, the combination bridge rail system as a whole had not been evaluated to any crash test standards. Iowa DOT desired that researchers at Midwest Roadside Safety Facility (MwRSF) design and test a combination bridge …

Investigating Students’ Perception Using Construction Management Simulations, Saeed Rokooei, James D. Goedert, Asregedew Woldesenbet

Department of Construction Engineering and Management: Faculty Publications

Today, construction programs are incorporating a wide variety of active learning methods in their curricula to improve student learning outcomes and induce a more knowledge retention rate. Simulations and educational games are one of the fast growing and effective active learning methods that have been implemented in many programs. However, there are few instances of such learning methods applied in construction programs and a limited number of research projects have been conducted to investigate short-term and long-term outcomes of these methods and applications. This paper presents construction students’ perceptions of tested simulations with regards to the features, knowledge gained, level …

Introduction To Water Resources Systems - University Of Colorado Boulder, Joseph Kasprzyk

All ECSTATIC Materials

This is the introductory lecture to a Water Resource Systems and Management class from Spring 2017 at the University of Colorado Boulder, by Joseph Kasprzyk. Learning goals include (i) defining integrated water resources management, (ii) identifying Colorado water management issues (ii) identifying how RiverWare simulation and optimization can be used to develop water plans (iii) use the HyMod model to perform rainfall-runoff modeling (iv) generating random parameter samples and understanding how parameter uncertainty affects model results.

Exploratory Assessment Of Roadway Infrastructure Adaptation To The Impacts Of Sea-Level Rise, Mostafa Batouli

FIU Electronic Theses and Dissertations

Transportation agencies in coastal urban areas face a significant challenge to enhance the long-term resilience of their networks to flooding and storm surge events exacerbated by sea level rise. The problem of sea-level rise adaptation is characterized by deep uncertainty that makes it complex to assess the value of adaptation investments. To enable informed adaptation decisions, the present study created a dynamic stochastic modeling framework based on the theoretical underpinnings of complex adaptive systems that integrates: (i) stochastic simulation of sea-level rise stressors based on the data obtained from downscaled climate studies pertaining to future projections of sea-level and precipitation; …

A System-Of-Systems Framework For Assessment Of Resilience In Complex Construction Projects, Jin Zhu

FIU Electronic Theses and Dissertations

Uncertainty is a major reason of low efficiency in construction projects. Traditional approaches in dealing with uncertainty in projects focus on risk identification, mitigation, and transfer. These risk-based approaches may protect projects from identified risks. However, they cannot ensure the success of projects in environments with deep uncertainty. Hence, there is a need for a paradigm shift from risk-based to resilience-based approaches. A resilience-based approach focuses on enhancing project resilience as a capability to cope with known and unknown uncertainty. The objective of this research is to fill the knowledge gap and create the theory of resilience in the context …

Development Of A Transition Between An Energy-Absorbing Concrete Barrier And A Rigid Concrete Buttress, Tyler Schmidt

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

From 2010 to 2015, MwRSF researchers developed the RESTORE barrier, which is a restorable MASH TL-4 median barrier with a steel and concrete rail supported by elastomer posts and steel skids. The research effort reported herein describes the initial development of a transition from the RESTORE barrier to a rigid TL-4 concrete buttress.

The previously-developed RESTORE barrier LS-DYNA model was validated against three full-scale vehicle crash tests. Several design concepts were generated through a series of brainstorming efforts. The primary transition concept consisted of a pin and loop connection between the RESTORE barrier and rigid concrete buttress, which was designed …

Water Resources Systems Analysis - University Of Texas San Antonio, Marcio Giacomoni

All ECSTATIC Materials

Systems Analysis methods use algorithmic and mathematical approaches for problem-solving. These are powerful methods that can be applied to solve complex design and management problems for water resources systems and other engineering areas. This class will focus on optimization methods, such as linear programming, integer programming, nonlinear programming, genetic algorithms, and dynamic programming, and their application to water resources systems. Advanced Systems Analysis methods, including sensitivity analysis, alternatives generation, and multi-objective optimization will be introduced to address the complexities associated with public sector decision-making. Course taught at University of Texas San Antonio.

Estimation Of Optimal Productivity In Labor-Intensive Construction Operations, Krishna Prasad Kisi

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

In an attempt to evaluate the efficiency of labor-intensive construction operations, project managers typically compare actual with historical productivity for equivalent operations. However, this approach toward examining productivity only provides a relative benchmark for efficiency and may lead to the characterization of operations as objectively efficient when in reality such operations might simply be comparably efficient.

Optimal productivity is the highest sustainable productivity achievable under good management and typical field conditions. Optimal productivity is useful in the determination of the absolute efficiency of construction operations because an accurate estimate of optimal labor productivity allows for the comparison of actual vs. …

Water Resources Systems Analysis - Colorado State University, Darrell Fontane

All ECSTATIC Materials

Applications of systems analysis, simulation and optimization techniques in water resources planning and management. Course taught at Colorado State University.

Railroad Capacity Tools And Methodologies In The U.S. And Europe, Hamed Pouryousef, Pasi Lautala, Thomas White

Michigan Tech Publications

A growing demand for passenger and freight transportation, combined with limited capital to expand the United States (U.S.) rail infrastructure, is creating pressure for a more efficient use of the current line capacity. This is further exacerbated by the fact that most passenger rail services operate on corridors that are shared with freight traffic. A capacity analysis is one alternative to address the situation and there are various approaches, tools, and methodologies available for application. As the U.S. continues to develop higher speed passenger services with similar characteristics to those in European shared-use lines, understanding the common methods and tools …

Inland Waterway Operational Model & Simulation Along The Ohio River, Doug Kreis, Roy E. Sturgill, Brian K. Howell, Christopher W. Van Dyke, D. Stephen Voss

Kentucky Transportation Center Research Report

The inland waterway system of the U.S. is a vital network for transporting key goods and commodities from the point of production to manufacturers and consumers. Shipping materials via the inland waterways is arguably the most economical and environmentally friendly option (compared to hauling freight by trains or railways). Despite the advantages the inland waterways enjoys over competing modes, key infrastructure – such as locks and dams, which help to control water levels on a number of rivers and make navigation possible – is declining. Limited funds have been allocated to make the necessary repairs to lock and dam facilities. …

Assessment Of Policies For Innovative Financing In Infrastructure Systems, Ali Mostafavi, Dulcy Abraham, Charlene Sullivan

Infrastructure System-of-Systems (I-SoS ) Research Group

Infrastructure systems are drivers of the economy in the nation. A dollar spent on infrastructure development yields roughly double the initial spending in ultimate economic output in the short term; and over a twenty-year period, and generalized ‘public investment’ produces an aggregated $3.21 of economic activity per $1.00 spent [1]. Thus, formulation of policies pertaining to infrastructure investment and development is of significance affecting the social and economic wellbeing of the nation. The aim of this policy brief is to evaluate innovative financing in infrastructure systems from two different perspectives: (1) through consideration of the current condition of infrastructure in …

Generic Incident Model For Investigating Traffic Incident Impacts On Evacuation Times In Large-Scale Emergencies, Andrew J. Collins, Peter Foytik, Erika Frydenlund, R. Michael Robinson, Craig A. Jordan

VMASC Publications

Traffic incidents cause a ripple effect of reduced travel speeds, lane changes, and the pursuit of alternative routes that results in gridlock on the immediately affected and surrounding roadways. The disruptions caused by the secondary effects significantly degrade travel time reliability, which is of great concern to the emergency planners who manage evacuations. Outcomes forecast by a generic incident model embedded in a microscopic evacuation simulation, the Real-Time Evacuation Planning Model (RtePM), were examined to quantify the change in time required for an emergency evacuation that results from traffic incidents. The incident model considered vehicle miles traveled on each individual …

Dynamics And Dislodgment From Pore Constrictions Of A Trapped Nonwetting Droplet Stimulated By Seismic Waves, Wen Deng, M. Bayani Cardenas

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Seismic waves affect fluid flow and transport processes in porous media. Therefore, quantitative understanding of the role of seismic waves in subsurface hydrodynamics is important for the development of practical applications and prediction of natural phenomena. We present a theoretical fluid dynamics model to describe how low-frequency elastic waves mobilize isolated droplets trapped in pores by capillary resistance. The ability of the theoretical model to predict the critical mobilization amplitudes (A_c) and the displacement dynamics of the nonwetting droplet are validated against computational fluid dynamics (CFD) simulations. Our theory has the advantage of rapid calculation of A_{c …}

The Impact Of Various Steel Stud Wall Frame Components On Energy Efficiency Analysis – Case Study, Aiyin Jiang

Construction Management Faculty Research and Scholarship

Steel stud framing is an excellent alternative to wood stud framing in residential construction. Steel framing is structurally sound, sustainable, and resistant to mold and insect infestation. However, the use of steel framing in the residential market remains low, due in large part to concerns on the thermal performance of steel. Over the past several years, engineers and constructors have increased the thermal resistance of steel stud walls through various wall assembly improvements, the impact of these components on energy efficiency is unclear. This study applies computer software to simulate the performance of various steel stud wall system assemblies. This …

Microsimulation Evaluation Of Eurocode Load Model For American Long-Span Bridges, Bernard Enright, Colm Carey, Colin Caprani

Articles

The ability to accurately predict traffic loading is essential for cost-effective bridge maintenance and repair programs. The traffic load model currently used in the United States for the design of long-span bridges was developed over three decades ago. In the meantime vehicle characteristics and traffic patterns have changed. The Eurocode for traffic loading is more recent, but was calibrated only for bridges up to 200 m long. In this work, Weigh-In-Motion traffic records from 11 different sites across Alabama are used to establish congested traffic loading. Traffic microsimulation is used to generate the congestion, based on the real traffic data. …

A Petri Net Simulation Model For Virtual Construction Of Earthmoving Operations, F. F. Cheng, Y. W. Wang, Yong Bai

Civil and Environmental Engineering Faculty Research and Publications

A common and extended Petri net simulation framework for virtual construction of earthmoving operations is developed to simulate dynamic changes of workflow and information flow in the earthmoving construction process and illustrate the constraint relationship between various operational equipment and construction restrictions. The proposed framework considers factors that influence earthmoving operations including randomness of construction activities, individual preference of equipment scheduling, and constraint relationship between equipment and construction environment. With the given equipment availability and project indirect cost, the framework can predict construction situation, equipment utilization rate, estimated duration and cost to achieve visualized and intelligent scheduling of virtual construction …