Engineering Commons^™

Numerical Simulation Of Mechanical Performance For Anti‑Collision Steel Pontoon, Han Xiaolei, Wang Bo, Li Weidong

Journal of China & Foreign Highway

Anti-collision steel pontoo n has good plasticity and energy absorption properties in ship-bridge collision.To explore the factors affecting the anti-collision performance of the anti-collision pontoon,a collision model composed of ship,anti-collision pontoon,and pier system was built based on finite element software Ansys/LS-DYNA.The collision mechanism and process were numerically simulated,and the effects of connection type between anti-collision pontoon and pier,peak angle of pontoon,and anti-collision pontoon stiffness on the collision force of the pier were investigated.The three-stage division method of collision force curve was put forward.The analysis shows that the fixed inwall of the anti-collision steel pontoon and connection to the pier surface …

Deformation And Damage Characteristics Of A Newly Operated Tunnel Caused By Above Foundation Pit Construction, Liu Jiqiang, Zhu Min, Hao Kun, Chen Dengwei, Chen Xiangsheng

Journal of China & Foreign Highway

The construction of foundation pits in granite residual soil layers is prone to causing upheaval deformation and structural damage in shield tunnels below.Based on the engineering case of a newly operated metro tunnel collinear with the above long-distance deep foundation pit in Shenzhen,a three-dimensional finite element model was established to investigate the variation law of the heave and horizontal convergence of the shield tunnel caused by the deep foundation pit excavation.The correlation between the longitudinal stress of the lining structure and the damage was analyzed.The results indicate that the tunnel deformation caused by foundation pit unloading is primarily vertical heave,accompanied …

Dynamic Response Rules Of Adjacent Buildings To Blasting Construction In Shallow Buried Tunnels, Luo Yanping, Li Jigang, Wang Sheng, Zeng Bin, Lai Jinxing, Feng Zhihua, Qiu Junling

Journal of China & Foreign Highway

In order to study the dynamic response rule of overlying buildings during blasting construction in shallow buried tunnels,the urban tunnel in Fuzhou was taken as the engineering background,and the on-site monitoring and Ansys/LS-DYNA simulation were used to analyze the structural response of overlying buildings.The monitoring results show that the building is most obviously affected by blasting in the vertical direction and has an obvious elevation amplification effect,and the maximum vibration velocity is 2.45 cm/s.The vibration velocity in all directions gradually decreases and tends to be stable with the increase in explosion center distance and decays rapidly when the explosion center …

Deflection Basin Characteristics Of Distressed Roads Under Moving Load, Cai Yingchun, Xie Shenjian

Journal of China & Foreign Highway

The deflection basins of roads under moving load imply the distress information of subgrade and pavement.Therefore,how to use the information of deflection basins under moving load to rapidly test road distresses non-destructively has received much attention.In this paper,the finite element model of semi-rigid base asphalt pavement was established.By setting different types and degrees of finite element distress models,the continuous changes of surface deflection basins under moving load were analyzed.The results show that when the load moves to the distress area,the center deflection value of surface deflection basins in each distress model will become larger.When transverse cracks appear in the pavement …

Curing Mechanism And Influencing Factors Of Cement Mixing Piles Reinforcing Peat Soil, Feng Rongxian, Zhong Gaibing, Liu Liang, Liang Jianyuan, Gu Meixiang

Journal of China & Foreign Highway

The cement mixing pile is used to reinforce the deep peat soil foundation in Malaysia's east coast railway construction.The key in this project is to determine the cement mix proportion and additives.Considering the high organic matter content and strong environmental acidity of coastal peat soil,physical and mechanical tests of peat soil and laboratory uniaxial compression tests of cement soil under different mix proportions and influencing factors were conducted.Test results show that the mean compressive strength decreases by 0.35 MPa with the increase in cement-water from 0.5 to 0.9.Adding mineral powder gives a relatively poor curing effect while adding fly ash …

Safety Of Optimized Concrete Median Barrier Without Planting Soil, Zhong Chunyao, Ma Qing, Li Yangfan, Gong Shuai, Liu Siyuan, Yan Shuming

Journal of China & Foreign Highway

In order to study the safety of optimized concrete median barrier without planting soil,the technology combining computer simulation,sled test,and full-scale impact test of real vehicles was adopted for analysis and verification.In addition,a scheme was proposed to improve the anti-overturning ability of the barrier without planting soil by strengthening the supporting block,and the scheme of setting a 20 cm-high supporting block between the barrier walls was optimized.The safety of the barrier scheme was evaluated by taking the most unfavorable large truck as an example.The results show that the protection level of the optimized concrete median barrier without planting soil is SAm, …

Aided Design Method And Application Of Rutting Prevention And Maintenance In Asphalt Pavement Based On Digital Holographic 3d Detection, Wang Jingfei, Wang Wang, Xu Xinquan, Huang Zhijian, Ti Jing, Yao Yanru

Journal of China & Foreign Highway

As one of the common diseases of asphalt pavement,rutting has significant impacts on the service life and traffic safety of the pavement.Mild rutting in asphalt pavement during preventive maintenance can lead to increased use of maintenance materials due to rutting deformation.Accurately calculating the amount of materials needed to fill rutting in maintenance designs is of great significance for ensuring maintenance quality and efficiency.Based on the requirements of maintenance engineering,this paper analyzed the problems in maintenance designs that use traditional methods and the data they generate for rutting detection.A design method was proposed for rutting prevention and maintenance in asphalt pavement,assisted …

Electronic Properties Of Group-Iii Nitride Semiconductors And Device Structures Probed By Thz Optical Hall, Nerijus Armakavicius, Philipp Kühne, Alexis Papamichail, Hengfang Zhang, Sean Knight, Axel Persson, Vallery Stanishev, Jr-Tai Chen, Plamen Paskov, Mathias Schubert, Vanya Darakchieva

Department of Electrical and Computer Engineering: Faculty Publications

Group-III nitrides have transformed solid-state lighting and are strategically positioned to revolutionize high-power and high-frequency electronics. To drive this development forward, a deep understanding of fundamental material properties, such as charge carrier behavior, is essential and can also unveil new and unforeseen applications. This underscores the necessity for novel characterization tools to study group-III nitride materials and devices. The optical Hall effect (OHE) emerges as a contactless method for exploring the transport and electronic properties of semiconductor materials, simultaneously offering insights into their dielectric function. This nondestructive technique employs spectroscopic ellipsometry at long wavelengths in the presence of a magnetic …

A Smart Energy Monitoring System Using Esp32 Microcontroller, Ehab Bayoumi

Mechanical Engineering

Gaza’s electrical deficit has resulted in the rise of new energy suppliers that sell power from private generators at higher prices. Consumers have challenges because they cannot tell whether their energy originates from the utility or private generators, resulting in unexpectedly large bills owing to a lack of an electronic monitoring system. This study fills this gap by developing a low-cost IoT energy monitoring system that provides real-time information on energy use (hourly, daily, and monthly) to assist consumers in managing their usage and ex penditures. An ESP32 microcontroller is used in the system to gather data from energy meters, …

Enhancing The Performance Of Interdependent Stormwater Drainage And Roadway Systems Under Future Conditions, Chao Ye

USF Tampa Graduate Theses and Dissertations

Flooding can cause extensive and devastating damage to human properties, including damage to homes, businesses, infrastructure systems, and personal belongings and it has become a threatening challenge during the past decades due to the massive damage brought to communities, infrastructures, and ecosystems. As climate change intensifies, the frequency and severity of flooding issues are expected to increase, exacerbating the existing flooding risks for vulnerable communities. Various approaches of modeling, optimizing, and designing for multiple levels of flooding problems have been adopted to deal with flooding control studies and research to alleviate the flooding risks on multiple levels of communities. This …

How Do Preservice Teachers Learn To Teach Integrated Computational Thinking?: Evidence From Planning, Enactment, And Reflection, Rachael Dektor, Samuel Severance, Kip Téllez

Journal of Computer Science Integration

This study examines pre-service teachers’ (PSTs) beliefs and understandings about computational thinking (CT) integration and lesson implementation over time. Utilizing a design-based research approach, 3 PSTs led the co-design of integrated CT lessons with support from researchers and enacted these CT integrated lessons with K-5 students. All PSTs participated in a whole-group CT workshop and engaged in one-on-one lesson design sessions with a researcher. We utilized a grounded theory approach to qualitatively analyze pre-surveys, semi-structured interviews, and video data of three PSTs enacting their lessons. We found that PSTs’ initial beliefs about CT instruction – including the importance of it …

The Role Of Spontaneous Activity In Maturation Of The Calyx Of Held Nerve Terminal And Its Synaptic Target In The Medial Nucleus Of The Trapezoid Body, Daniel Tatsuo Heller

USF Tampa Graduate Theses and Dissertations

Neural circuit formation is a complex process involving synergistic roles between neurons and glial cells regulated by coordinated genetic and molecular cues and activity-dependent mechanisms. The canonical pathway for synapse formation begins with neurogenesis and migration followed by axonal outgrowth and dendritic arborization allowing for the capture and formation of nascent synapses. These initial synaptic contacts are exuberant in nature ensuring proper neural connectivity and undergo a period of pruning of superfluous inputs followed by maturation and strengthening of the remaining contacts. This maturation includes pre- and postsynaptic specialization of the active zone, localization and clustering of ion channels, and …

Correction: Graph Theory And Graph Neural Network Assisted High-Throughput Crystal Structure Prediction And Screening For Energy Conversion And Storage, Joshua Ojih, Mohammed Al-Fahdi, Yagang Yao, Jianjun Hu, Ming Hu

Faculty Publications

Correction for ‘Graph theory and graph neural network assisted high-throughput crystal structure prediction and screening for energy conversion and storage’ by Joshua Ojih et al., J. Mater. Chem. A, 2024, 12, 8502–8515, https://doi.org/10.1039/D3TA06190F.

On page 8511 in section 3.2 of the published article, the text “The single values of bonding and antibonding for each structure are obtained by performing integration over COHP curves for each atomic pair as evaluated by the LOBSTER package” should have included citations to six references. The missing references are listed below as ref. 1–6.

The Royal Society of Chemistry apologises for …

Problem Solving / Javascript Programming, Sarah Zelikovitz, Orit D. Gruber

Open Educational Resources

This Lab Experiment focuses on JavaScript Programming. Upon completing the lab, you will be able to understand the following:

· The definition of Algorithmic Problem Solving.

· The role of JavaScript in web pages.

· The concept of Iteration in computer programming.

Design Of A Pick-And-Place Robot With Computer Vision And Optimized Sorting Algorithms, Dan Kilula

Student Theses and Dissertations

In computer science, the Multiple Travelling Salesman Problem (mTSP) is a special case of Travelling Salesmen where one salesman travels through a network of cities (end nodes) and goes back to the starting city (start node) rather than stopping at the targeted end node. Numerous search and optimization algorithms are used to find the most time-efficient path for the salesman to visit each node. In this work 3 optimization methods and algorithms such as linear programming and A* pathfinding are utilized and compared to solve the mTSP applied to a 3 degrees-of-freedom pick-and-place robot that uses computer vision to detect …

Probabilistic Estimation Of Cadence And Walking Speed From Floor Vibrations, Yohanna Mejiacruz, Juan M. Caicedo, Zhaoshuo Jiang, Jean M. Franco

Faculty Publications

Objective: This research aims to extract human gait parameters from floor vibrations. The proposed approach provides an innovative methodology on occupant activity, contributing to a broader understanding of how human movements interact within their built environment. Methods and Procedures: A multilevel probabilistic model was developed to estimate cadence and walking speed through the analysis of floor vibrations induced by walking. The model addresses challenges related to missing or incomplete information in the floor acceleration signals. Following the Bayesian Analysis Reporting Guidelines (BARG) for reproducibility, the model was evaluated through twenty-seven walking experiments, capturing floor vibration and data from Ambulatory Parkinson’s …

Automated Flood Prediction Along Railway Tracks Using Remotely Sensed Data And Traditional Flood Models, Abdul Rashid Zakaria, Thomas Oommen, Pasi Lautala

Michigan Tech Publications

Ground hazards are a significant problem in the global economy, costing millions of dollars in damage each year. Railroad tracks are vulnerable to ground hazards like flooding since they traverse multiple terrains with complex environmental factors and diverse human developments. Traditionally, flood-hazard assessments are generated using models like the Hydrological Engineering Center–River Analysis System (HEC-RAS). However, these maps are typically created for design flood events (10, 50, 100, 500 years) and are not available for any specific storm event, as they are not designed for individual flood predictions. Remotely sensed methods, on the other hand, offer precise flood extents only …

Lunar: Automated Input Generation And Analysis For Reactive Lammps Simulations, Josh Kemppainen, Jacob R. Gissinger, S. Gowtham, Gregory Odegard

Michigan Tech Publications

Generating simulation-ready molecular models for the LAMMPS molecular dynamics (MD) simulation software package is a difficult task and impedes the more widespread and efficient use of MD in materials design and development. Fixed-bond force fields generally require manual assignment of atom types, bonded interactions, charges, and simulation domain sizes. A new LAMMPS pre- and postprocessing toolkit (LUNAR) is presented that efficiently builds molecular systems for LAMMPS. LUNAR automatically assigns atom types, generates bonded interactions, assigns charges, and provides initial configuration methods to generate large molecular systems. LUNAR can also incorporate chemical reactivity into simulations by facilitating the use of the …

Photodegradation And Microencapsulation Of Organic Thermochromic Material For Application As Building Coating Envelope, Sushant Madhukar Nagare

USF Tampa Graduate Theses and Dissertations

Due to exponential urbanization, residential building electrical loads have increased over the past decades. Also, deforestation has led to increased urban heat island effects, due to which summer has been scorching and winter has become freezing. This further increases the load on generation due to the extensive use of heating and cooling systems. New techniques, such as cool building materials and green building concepts, compensate for the load. The building can be coated with a material that has heat reflectivity capability for summer and heat-trapping capability for winter. One such material is thermochromic, which turns white upon heating and black …

Advances In Model Reference Adaptive Control: Exploring Gain Scheduling, Scalability, And Time-Varying Command Following, Jesse Jaramillo

USF Tampa Graduate Theses and Dissertations

Feedback control architectures are fundamental for achieving a desired response in physical systems. A robust and reliable design must account for system uncertainties and exogenous disturbances, which may arise from phenomena such as modeling approximations, nonlinearities, degraded modes of operations, wind gusts, or structural impairments. Two widely recognized methods to mitigate the negative impact of uncertainties and disturbances are robust and adaptive control architectures. Specifically, robust control designs ensure stability by considering a worst-case scenario, which can potentially lead to suboptimal performance or steady-state errors depending on the nature of the uncertainty. In contrast, adaptive control designs offer the capability …

Work In Progress: Development Of A Bootcamp For Freshman Student Success During Covid-19 Transition, Noe Vargas Hernandez, Arturo A. Fuentes, Javier A. Ortega, Laura Benitez, Edna Orozco-Leonhardt

Mechanical Engineering Faculty Publications

Assessment results show that passing rates in introductory courses and retention rates of firstyear students in the College of Engineering and Computer Science at The University of X, a predominantly Hispanic Serving Institution (HSI), significantly dropped with the onset of COVID-19. These results and trends highlight the academic preparation of incoming students, particularly the new cohort of underrepresented Hispanic students from underserved and challenged communities in the region, who may not have the necessary skills (e.g., adaptability, persistence, and performance) for the rigor of engineering education. To address this challenge, an onboarding “boostcamp” was created for incoming and transfer students …

Board 294: Hsi Implementation And Evaluation Project: The Freshman Year Innovator Experience (Fyie): Bridging The Urm Gap In Stem, Noe Vargas Hernandez, Javier Ortega, Arturo A. Fuentes, Eleazar Marquez

Mechanical Engineering Faculty Publications

The Freshman Year Innovator Experience (FYIE) program at The University of X, a Minority Serving Institution (MSI), aims to enhance the freshman experience for incoming students by developing key academic success skills. The program is developing self-transformation skills in freshman mechanical engineering students to help them overcome academic and professional challenges exacerbated by the COVID-19 pandemic. FYIE participants are taking two courses simultaneously: Introduction to Engineering (Course A) and Learning Frameworks (Course B). In Course A, students will complete a 6-week engineering design project, and in Course B, they are completing a 6-week academic career path project. During these parallel …

Work In Progress: Teaching Engineering Students To Self-Transform: Parallelisms Between Product Innovation And Student Career Path Planning, Noe Vargas Hernandez, Javier Ortega, Arturo A. Fuentes, Eleazar Marquez

Mechanical Engineering Faculty Publications

Freshman engineering students can have a hard time transitioning to college. The freshman year is critical to the students’ academic success; in this year they learn basic skills and establish essential networks with other students, faculty, and resources. How can we help these freshman engineering students in this transition? We propose that freshman students can learn from the engineering design innovation process and apply it by analogy to the design of their academic pathways. There are multiple similarities between product innovation (i.e., technology) and the continuous academic challenges faced by the student. Engineers as designers and innovators have a vast …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Factors Influencing The Productivity And Technology Optimization Of Horizontal Wells For Moderately Deep Coalbed Methane In The Northern Zhengzhuang Block, Zhang Cong, Li Kexin, Jia Huimin, Zhang Wuchang, Yang Ruiqiang, Li Jun, Wang Qi, Hou Weiming

Coal Geology & Exploration

[Objective] Hydraulic fracturing of vertical wells was adopted during the early production of moderately deep coalbed methane (CBM) of the northern Zhengzhuang block in the Qinshui Basin, generally yielding low productivity and inefficiency. In contrast, single-casing fracturing of horizontal wells has increased the single-well production to 10‒50 times that of vertical wells, establishing horizontal wells as the dominant development well type. However, the horizontal wells differ greatly in CBM production. This study aims to determine the factors influencing the productivity of horizontal wells using staged fracturing for moderately deep CBM in the northern Zhengzhuang block and improve the production performance. …

Characteristics Of The Pore And Seepage System Of Deep Coalbed Methane In The Baijiahai Uplift, Junggar Basin, Xinjiang, Chen Heqing, Yang Zhaobiao, Li Daoqing, Xu Miaomiao, Liang Yuhui, Liu Changqing, Wang Yuqiang

Coal Geology & Exploration

[Objective] Xinjiang boasts abundant deep coalbed methane (CBM) resources, with Jurassic coal seams in the Baijiahai uplift of the Junggar Basin identified as a favorable target area for deep CBM exploration and exploitation. The pore and seepage system of deep CBM directly determines its recoverability. [Methods] Based on appraisal well Caimei 2-004H drilled the most recently in the Xinjiang oilfield in 2023, this study investigated in detail the pore and seepage system of coals in the Jurassic Xishanyao Formation in the Baijiahai uplift using scanning electron microscopy (SEM) observations, mercury injection capillary pressure (MICP), low-temperature liquid nitrogen adsorption, and carbon …

Impacts Of Observation Line Layout Morphology And Survey Point Missing On The Inversion Of Predicted Parameters Of Mining Subsidence, Guo Qingbiao, Yu Qing, Zheng Meinan, Luo Jin

Coal Geology & Exploration

[Objective] Accurate prediction parameters for mining subsidence are important basis for full cycle green coal mining, while inversion based on the subsidence data of observation lines serves as the main method to obtain these parameters. [Methods] To quantitatively analyze the impacts of the observation line layout morphology and survey point missing on the inversion of prediction parameters for mining subsidence, this study developed a probability integral model-based inversion method for these parameters using the chimpanzee optimization algorithm (ChOA). Using this method combined with digital simulation experiments, this study predicted subsidence parameters under six observation line morphologies and survey point missing …

Fracturing Evolutionary Law And Energy Utilization Efficiency Of Green Sandstones Under Different Loading Rates, Zhao Huanshuai, Pan Yongtai, Qiao Xin, Wang Xingyu, Yu Chao, Huang Jiacheng

Coal Geology & Exploration

[Objective] This study aims to explore the fracturing evolutionary laws and energy utilization efficiency of rocks under different loading rates is a pressing issue in the field of rock fragmentation and processing. [Methods] To this end, the microscopic parameters of green sandstones were calibrated based on laboratory tests, followed by the identification of relationships between the macro- and microscopic mechanical responses of the sandstones. Using Particle Flow Code (PFC), this study investigated the stress-strain curves and stress chain distribution of green sandstones under different loading rates. Then, based on the fracturing and crack characteristics, this study analyzed the fracturing evolutionary …

Hydrochemical Characteristics And Genetic Mechanism Of Geothermal Water In The Wandong Geothermal Area Along The Moxi Fault In Western Sichuan, Huang Xun, Zhang Yunhui, Li Xiao, Lyu Guosen, Guo Hongyang

Coal Geology & Exploration

[Objective] Geothermal energy exploitation is identified as a vital way to achieve the goals of peak carbon dioxide emissions and carbon neutrality. The Moxi fault, located in the southern segment of the Xianshuihe fault zone in western Sichuan, boasts abundant geothermal resources, serving as a significant area for subsequent geothermal energy exploitation. [Methods] This study investigated the hydrogeochemistry of the Wandong geothermal area along the Moxi fault, analyzed the water-rock interaction process in the area based on the hydrochemical correlation, and calculated the reservoir temperatures and the mixing ratios of cold and hot water using geothermometers and the silica-enthalpy mixing …

Experimental Study On The Mechanics And Deformation Failure Characteristics Of Multi-Source Coal-Based Solid Waste Cemented Backfill, Yang Ke, Zhang Jiqiang, He Xiang, Wei Zhen, Zhao Xinyuan

Coal Geology & Exploration

[Objective] In order to study the mechanical properties and deformation failure laws of multi-source coal-based solid waste cemented backfill (CBSWCB), the uniaxial compression, acoustic emission response and microstructure test experiments were carried out with 5 types of typical coal-based waste. [Methods] The factors influencing the uniaxial compressive strength of CBSWCB, as well as their interaction, were analyzed, and a four-dimensional spatial visualization model of the factors influencing the compressive strength based on their interactions was established. Besides, the mechanical evolution characteristics and macroscopic deformation failure laws under uniaxial compression conditions were elaborated by referring to the acoustic emission and microstructure …