Digital Commons Network^™

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 …

Investigating The Impact Of Seawater Intrusion On The Operation Cost Of Groundwater Supply In Island Aquifers, Weijiang Yu, Domenico Baù, Alex S. Mayer, Lauren K. Mancewicz, Mohammadali Geranmehr

Michigan Tech Publications

Managing fragile island freshwater resources requires identifying pumping strategies that trade off the financial cost of groundwater supply against controlling the seawater intrusion (SWI) associated with aquifer pumping. In this work, these tradeoffs are investigated through a sensitivity analysis conducted in the context of an optimization formulation of the groundwater management problem, which aims at minimizing the groundwater supply operation cost associated with groundwater pumping and desalination treatment, subject to constraints on SWI control, as quantified by the water table drawdown over the well (∆s), the reduction in freshwater volume (∆FV) in the aquifer, or the salt mass increase (∆SM) …

Channel Morphology Of A Leaky Coastal Plain River: The Congaree River, Sc 1884-2022, William Nicholas Logan

Theses and Dissertations

Downstream changes in river planform can be associated with changes in geologic controls and often signal changes in channel geometry, bed slope, or bed material grain size. While previous studies documented downstream trends in channel geometry and planform for a variety of rivers, there is a gap in the literature on spatial and temporal trends in channel geometry on the fluvial part of Coastal Plain rivers, i.e., the not-tidally influenced part. The literature highlights the existence of crevasse splays in natural levees that allow floodplain inundation below bankfull conditions as unique feature of channels and floodplains in the Coastal Plain. …

Construction Aspects And Seismic Analysis Of Typical Buildings In Dolpo, Lhakpa Tsering

Independent Study Project (ISP) Collection

This study delves into the construction aspects and seismic analysis of typical buildings in the challenging terrain of Dolpo, situated within the Himalayan mountain range. Dolpo's unique geological and geographical characteristics, combined with its susceptibility to seismic activity, make it crucial to investigate and understand the dynamics of construction in this remote region. The research explores traditional and contemporary building practices, aiming to elucidate the interplay between construction methodologies and seismic resilience. Through a comprehensive examination of the geological context, structural design, and seismic vulnerability, this study contributes valuable insights to inform the development of robust and earthquake-resistant building strategies …

Electric Freight Transportation System Planning And Truck Operation Optimizations, Xuanke Wu

Theses and Dissertations

The substantial demand for fossil fuel consumption is a significant contributor to greenhouse gas emissions, drawing considerable public attention to health and environmental problems. As a result, vehicle electrification is currently recognized as the most effective approach to reduce CO2 emissions from transportation. However, compared to traditional fossil fuel-powered vehicles, electric vehicles have notable disadvantages, including higher upfront purchasing price, longer recharging time, and most significantly, lower driving ranges. All these challenges can potentially result in increased overall operational costs for logistics companies. This thesis proposes a comprehensive optimization modeling framework for electric freight transportation system planning and operations with …

Erosion Resistant Rock Shoulder, Chung R. Song, Richard L. Wood, Basil Abualshar, Mark O'Brien, Bashar Al-Nimri, Mitra Nasimi

Nebraska Department of Transportation: Research Reports

Highway shoulder rocks are exposed to continuous erosion force due to unexpected floodings caused by climate change. The evaluation methods of the erosion resistance of highway shoulder rocks are not currently well-developed. This study developed a new large-scale testing device, the University of Nebraska-Lincoln Erosion Testing Bed (UNLETB), which has the capability of testing the shoulder gravels. Different gradations were tested using UNLETB, and the results distinguished a high-resistant group and a low-resistant group. The low resistant group was treated with different binding agents: Ammonium Lignosulfonate (LIGNO10), Soybean Soap Stock, and DirtGlue. The treated samples showed better erosion resistance based …

An Effective Model For Dynamic Properties Of Local Soils And Their Influence On Seismic Response Of A Typical Reinforced Concrete Building, Kaveh Zehtab

Civil & Environmental Engineering Theses & Dissertations

This dissertation presents an effective model to determine the dynamic properties of local soils and their impact on the seismic response of a typical mid-height reinforced concrete building. The results of the study suggest that the use of global models and empirical relationships for the dynamic properties of soils may not consider the effects of unique stress conditions on the cyclic response of the foundation soil. The study also investigates the seismic response of a site in central Adapazarı, Turkey, where four- to seven-story buildings suffered significant damage during the 1999 Kocaeli earthquake. A new model is presented that combines …

Lithium Extraction From Aqueous Solution Using Magnesium Doped Lithium Ion-Sieve Composite, Ujjwal Pokharel

Civil & Environmental Engineering Theses & Dissertations

This study focused on the development of a magnesium doped ion-sieve composite to extract lithium from an aqueous solution using adsorption process. The extraction process will provide a sustainable alternative to the currently practiced solar evaporation/concentration method which is very slow (takes 24 months) and water intensive. Currently, most of the lithium in the world comes from the mining of lithium or from the evaporative extraction process from the brine. Additionally, the Salton Sea area geothermal brines are recognized as potentially important domestic sources of lithium. Lithium concentration in geothermal brines from the Salton Sea area is reported to be …

System Dynamic Modeling To Study The Impact Of Construction Industry Characteristics And Associated Macroeconomic Indicators On Workforce Size And Labor Retention Rate, Tamima Elbashbishy, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Limited skilled labor has been one of the greatest challenges facing the construction industry. The COVID-19 pandemic has further exaggerated the already strained construction labor market, leading to an additional negative impact. One of the major contributors to skilled labor shortages in construction is the issue of labor retention. Overall, this is a complex and dynamic situation that requires effective and efficient simulation-based techniques to capture the interdependent relationships that affect the performance of the construction labor market. This paper fills this knowledge gap. To this end, the authors used a multistep research methodology that involved (1) identifying factors that …

Semi-Annual Progress Report #12, Missouri University Of Science And Technology. Inspire - University Transportation Center

Semi-Annual Progress Reports

No abstract provided.

Designing A Model Of Solar Photovoltaic Water Pumping System For Off-Grid Localities In Tanzania, Imani Mruma

Tanzania Journal of Engineering and Technology (TJET)

Modeling of photovoltaic (PV) water pumping system for rural water localities is vital especially in these modern days, in Tanzania. This is due to the rise of high number of solar-powered rural water projects constructed lacking appropriate design. The fate result into poor and substandard projects delivering below expectations. Kikombo Solar Water Project situated in Dodoma; Tanzania is one among poorly designed solar project chosen as a case study to validate proposed model. The main problem of Kikombo project is unsatisfactory amount of water from domestic points to satisfy population demand. This matter has been raised by pumping-station attendants and …

Assessment Of Spatial Variability Of Groundwater Potential Using Remote Sensing And Gis-Based-Criteria Evaluation For Dar Es Salaam, Tanzania, Augustina Alexander

Tanzania Journal of Engineering and Technology (TJET)

Groundwater is an important resource for the continuous provision of water supply in both urban and rural areas. Lack of enough knowledge about the spatial variability of groundwater potential zones (GWPZS) has a negative impact on groundwater extraction development and management and may result into over exploitation. In this study, analytic hierarchy approach (AHP)-coupled with multi criteria decision analysis (MCDA) and GIS techniques were employed to integrate hydrogeological, geological as well as topographical data to assess spatial variability of groundwater potential zones of Dar es Salaam city. Seven thematic layers such as lithology, slope, land-use, lineament, drainage, soil, and rainfall …

Vulnerable Road User Safety: Data Collection, Analysis, And Countermeasures, Anahita Kakhani

Theses and Dissertations

The safety of pedestrians and bicyclists (vulnerable road users) has become a paramount global concern, especially with a 53% and 31% surge in related crashes over the past decade in the U.S. Despite transportation agencies implementing various safety measures to address this issue, the number of severe injuries among these road users continues to climb annually. This underscores the urgent need for innovative methodologies and technologies to pinpoint the factors compromising their safety. To do so, this study aimed to introduce and employ techniques and countermeasures to gain deeper insight into risks faced by vulnerable road users. This study includes …

Modeling Leaf-Level Transpiration: Exploring The Consequences Of Assumed Saturated Vapor Pressure In Leaves, Danlyn L. Brennan

Dissertations and Theses

Understanding the dynamics of water transport through leaf intercellular airspaces (IAS) and its impact on transpiration is crucial for accurate predictions of plant water use and ecosystem response to changing climates. This study investigates the implications of assuming undersaturation of water vapor in the IAS for transpiration predictions and explores potential modifications to standard modeling approaches.

A dynamic 1D soil-plant-atmosphere continuum using a stomatal optimization model (SPAC-SOT) framework was used to simulate the response of tree species, P. edulis, to prolonged drought and varying environmental conditions. Comparisons between two model assumptions (saturated vs. undersaturated IAS) reveal notable differences in …

Developing A Smart And Sustainable Public Transportation System: A Case Study In Camden, New Jersey, Zahra Vafakhah

Theses and Dissertations

The transportation sector is a major contributor to air pollution and Greenhouse Gas (GHG) emissions. As a significant source of emissions, public transportation presents an opportunity for mitigation through electrification. However, transitioning to an electric bus fleet necessitates substantial investments in bus procurement and charging infrastructure. To address the associated costs, this study introduces a mixed-integer linear mathematical model developed to optimize the location of on-route fast charging stations within bus networks. The central objective of this optimization formulation is to minimize the overall cost of establishing the charging infrastructure. The study employs a real-world case study focusing on a …

Evaluation Of Digital Twin Approaches For Thermal Modeling And Energy Optimization For Existing Buildings, Jason Bastie Muermann

Theses and Dissertations

Residential, commercial, and industrial building sectors in the United States were responsible for 42% of the nation’s consumption of 100.2 quadrillion BTUs of energy in 2019 [1]. 80% of the nation’s energy is sourced from fossil fuels, including coal, natural gas, and petroleum. Fossil fuels are known contributors to carbon emissions and climate change, making energy reduction vital. Consequently, New Jersey Department of Military and Veterans Affairs (NJDMAVA) is tasked with evaluating energy consumption and efficiency in all New Jersey Army National Guard (NJARNG) facilities, as mandated by TAG Policy Letter 18-5, Executive Order 13990, and the Energy Independence and …

Dual Activation Of Peroxymonosulfate Using Mnfe2O4/G‑C3N4 And Visible Light For The Efficient Degradation Of Steroid Hormones: Performance, Mechanisms, And Environmental Impacts, Kitipong Poomipuen, Chainarong Sakulthaew, Chanat Chokejaroenrat, Athaphon Angkaew, Kanidrawee Techauay, Thapanee Poompoung, Kanokwan Teingtham, Piyaporn Phansak, Piyangkun Lueangjaroenkit, Daniel D. Snow

Daugherty Water for Food Global Institute: Faculty Publications

Single activation of peroxymonosulfate (PMS) in a homogeneous system is sometimes insufficient for producing reactive oxygen species (ROS) for water treatment applications. In this work, manganese spinel ferrite and graphitic carbon nitride (MnFe₂O₄/g-C₃N₄; MnF) were successfully used as an activator for PMS under visible light irradiation to remove the four-mostdetected- hormone-contaminated water under different environmental conditions. The incorporation of g-C₃N₄ in the nanocomposites led to material enhancements, including increased crystallinity, reduced particle agglomeration, amplified magnetism, improved recyclability, and increased active surface area, thereby facilitating the PMS activation and electron …

Feasibility Study Of Pavement Rutting Evaluation Method Based On Driving Vibration, Zhang Jinxi, Wang Peirong, Cao Dandan, Ceng Jingxiang

Journal of China & Foreign Highway

To explore the intelligent detection and monitoring methods of pavement performance, this paper utilized the self-developed driving data collection app to collect vibration acceleration and other data of the pavement during driving, and carried out the feasibility study of evaluating the pavement rutting by driving vibration. Firstly, the collected vibration acceleration data was processed for noise reduction, and the driving vibration characteristics in different working conditions were analyzed. Secondly, seven time domain indicators with high correlation between vibration acceleration and the rutting were extracted as the initial set of indicators, and the seven indicators were downscaled into two independent principal …

Influence Of Shear Deformation On Manufacturing And Erection Alignment, Wang Jin, Chen Changsong

Journal of China & Foreign Highway

This paper aims to study the effect of shear deformation on the manufacturing and erection alignment of main girders of free cantilever erection steel box girder bridges and better design the state of bridge formation state. To this end, it calculated the shear stress coefficient of uniformity of the steel box girder’s cross-section by adopting the finite element method and conducted comparison with the solid model of the plate and shell units of the steel box girder. The results show that the shear stress coefficient of uniformity calculated by finite element software is accurate and reliable. Additionally, simple modeling indicates …

Study On Temperature Gradient Of Long-Span Single-Box Double-Chamber Box Girder Bridge, Yang Wenbin

Journal of China & Foreign Highway

In view of the complex temperature effect of the single-box double-chamber box girders, this paper aimed to carry out the temperature gradient study of box girder cross-sections by employing a short-tower single-box double-chamber cable-stayed bridge with span arrangement of (120+120) m. 21 temperature sensors were installed at the cross-sections of large-mileage closure sections, with the set collection frequency of one time per hour and a wireless collection module for data collection. Meanwhile, temperature observation was carried out for a period of 171 d to obtain the distribution law of the temperature gradient in cross-sections of the closure sections. The study …

Experimental Study On The Influence Of Cantilevered Sidewalk On The Wind Resistance Of A Cable-Stayed Bridge With Pk Girder, Yu Zhenghua

Journal of China & Foreign Highway

Bilateral box steel main girders are widely employed in large-span double-plane cable-stayed bridges. These bridges are characterized by low frequency, small damping, and relatively light mass, and their wind resistance stability is a key problem to be solved in bridge construction. By taking the Pingnan super major cable-stayed bridge with a main span of 636 m on Pingrong Expressway under construction as the research project, this paper built a finite element spatial model of the bridge and analyzed the structural modal characteristics. Meanwhile, it carried out the main girder segmental model of elastically suspended vortex vibration and chatter vibration wind …

Orthogonal Analysis Of Influential Factors In Construction Of Portal Pier Foundations Adjacent To Existing Railway, Li Minghua, Feng Jiahui, Han Wenjing

Journal of China & Foreign Highway

To study the influencing factors of portal pier foundation construction adjacent to existing railway, this paper adopted the orthogonal test method based on numerical simulation to study the influence of five factors on the existing railway, including the length of bored piles, construction sequence of bored piles, excavation depth of foundation pits of the bearing platform, length of steel sheet piles, and number of steel sheet piles. The results show that during the bored pile construction stage, the most important factor is the construction sequence of bored piles. Meanwhile, during the stage of foundation pit excavation and substructure construction, the …

Optimization Design Of Highway Tunnel Inner Contour Based On Simu Lated Annealing Algorithm, Zhang Qingwei

Journal of China & Foreign Highway

To optimize the inner contour design of road tunnels, this paper regarded the inner contour design of a road tunnel as an optimization problem in certain conditions. By taking the area optimization as the objective, it introduced the simulated annealing algorithm to solve the problem based on the calculation model building of the inner contour of a single-centered circle with an inverted arch, with a program written for verification and analysis. The results show that the optimization design scheme is feasible and can provide an idea way for the inner contour design of road tunnels.

Comparison Of Specifications For Highway Safety Audi Ts Of China ， The United States ， And Australia, Li Jie, Han Huanhuan, Li Jia, Ren Yabo, Gong Ruiming

Journal of China & Foreign Highway

Traffic safety is one of the three major problems of transportation. To build a transportation power, China has proposed the call of “facilitating the transportation development from pursuing the speed and scale to paying more attention to quality and safety”, and improving the audit specifications of road safety is an important basis for increasing the transportation safety level. This paper firstly introduced the background where China, the United States and Australia issued the audit specifications of road safety, and then compared the differences between the three countries in the aspects of the audit process for road safety, audit indexes and …

Research On A Hub Interchange Scheme Under Special Terrain Conditions, Wang Jie, He Yajun

Journal of China & Foreign Highway

By combining the study process and conclusion of the interchange scheme of the Lugao hub as an important node of G4216 Jinyang-Ningnan Expressway Project, this paper discussed the ideas and methods of selecting the hub interchange shape under complex terrains and high functional requirements. It aimed to provide certain references for the design of hub interchange schemes in special Y-shaped terrain conditions. The Lugao hub interchange location is deeply cut by the Jinsha River and its branches, with narrow valley bottoms, extremely steep cross slopes, and harsh engineering construction conditions. Meanwhile, in the limited space, the specific requirements of the …

Structure Design Of Platform For Construction Of Inclined Pile Foundation On The Water Under Complex Hydrogeology Conditions, Cheng Tao, Fu Su, Deng Songtao

Journal of China & Foreign Highway

Based on the design of the pile foundation construction platform for the Yushan water intake in Daishan Port, this paper introduced the adoption of the support system combining the steel pile casing and steel pipe piles in complex hydrogeological conditions. Most of the pile foundations feature small embedded length and are inclined piles with weak lateral rigidity, and they cannot resist the horizontal loads such as wind-wave-current during the typhoon period. Therefore, this paper introduced several measures taken to improve the overall lateral stability of the platform. The first measure is to improve the boundary conditions of pile foundations by …

Study On Stability Analysis And Treatment Of A Expressway Landslide, Huang Hongchao

Journal of China & Foreign Highway

In highway construction of mountainous areas, landslides are easily triggered due to the complex geological conditions, thereby causing serious economic loss and even casualties. Therefore, the study of landslide treatment schemes has caught increasingly more attention from scholars. By taking the giant landslide treatment on a highway of southeastern Yunnan as an example, this paper analyzed the process and cause of giant landslide formation, and then conducted inverse calculations to determine the stability analysis parameters of landslides via combining the topography and geology and slope state before and after slope excavation. Finally, according to the calculation results of the residual …

Discussion On Treatment Scheme Of Soft Foundation Based On Cooperative Deformation Of Roadbed And Frame Structure, Liu Jizhong, Chen Kai, Yang Fengyu

Journal of China & Foreign Highway

In view of insufficient consideration of cooperative roadbed and structure deformation, by taking the soft foundation with frame structures in the fill roadbed as the research object, this paper adopted Midas GTS NX finite element analysis software to simulate the pavement settlement and plastic zone distribution of the soft foundation treated by cast-in-place piles. Considering that the stiffness difference between the roadbed and the frame structure can easily result in pavement cracking, a variable stiffness composite foundation treatment optimization scheme was proposed. This scheme coordinated the cooperative settlement and deformation of the roadbed and frame structure, and prevented the development …

Research On Effect Of Structural System On Static And Dyn Amic Stiffness Of Large-Span And Narrow Suspension Bridges, Song Songke, He Jiayong, Chen Qian, Du Taoming, Li Yongle, Yu Chuanjin

Journal of China & Foreign Highway

Large-span and narrow suspension bridges featuring flexible structures and low overall stiffness have prominent wind resistance problems. Structural static and dynamic stiffness is the basic parameter for wind resistance of long-span bridges. By taking a large-span and narrow suspension bridge as the research project, this paper comparatively analyzed the effects of parameters such as stiffened girder stiffness, main cable span ratio, main cable spacing, and lifting point width on the static and dynamic stiffness based on the theory of spatial cable segmental suspension lines and three-dimensional finite element models of bridges under multi-working condition systems. The results show that the …

Risk Assessment Calculation Of Layered Surrounding Rock Tunnel Based On Combination Weight-Eahp-Ncm Model Theory, Yang Yongbin, Wang Qing, Wang Yijun, Gao Weizheng, Li Yongliang

Journal of China & Foreign Highway

To accurately assess and calculate the structural stability of layered surrounding rock tunnels during construction, this paper firstly constructed a risk assessment index system for layered surrounding rock tunnels based on the consideration of factors of hydrogeology, structural surfaces, engineering, external forces, and topography and geomorphology. Based on the Delphi method (DELPHI) and entropy weight method (EWM), the combination of indicators was assigned. Based on the typical event samples and the mining of classical domains-joint domains of the assessment system, the extension analytic hierarchy process calculation model (EAHP) and normal cloud computing model (NCM) were built to assess the stability …