Engineering Commons^™

Modeling Study Of Si3N4 Waveguides On A Sapphire Platform For Photonic Integration Applications, Diandian Zhang, Shui-Qing Yu, Gregory J. Salamo, Richard A. Soref, Wei Du

Electrical Engineering and Computer Science Faculty Publications and Presentations

Sapphire has various applications in photonics due to its broadband transparency, high-contrast index, and chemical and physical stability. Photonics integration on the sapphire platform has been proposed, along with potentially high-performance lasers made of group III–V materials. In parallel with developing active devices for photonics integration applications, in this work, silicon nitride optical waveguides on a sapphire substrate were analyzed using the commercial software Comsol Multiphysics in a spectral window of 800~2400 nm, covering the operating wavelengths of III–V lasers, which could be monolithically or hybridly integrated on the same substrate. A high confinement factor of ~90% near the single-mode …

Performance And Enhanced Efficiency Induced By Cold Plasma On Sapo-34 Membranes For Co2 And Ch4 Mixtures, Fnu Gorky, Vashanti Storr, Grace Jones, Apolo Nambo, Jacek B. Jasinski, Maria L. Carreon

Chemical Engineering Faculty Publications and Presentations

In this study, we investigate the influence of cold-plasma-induced enhanced performance and efficiency of SAPO-34 membranes in the separation of CO₂ and CH₄ mixtures. Placing the herein presented research in a broader context, we aim to address the question of whether cold plasma can significantly impact the membrane performance. We subjected SAPO-34 membranes to plasma mild disturbances and analyzed their performance in separating CO₂ and CH₄. Our findings reveal a notable enhancement in membrane efficiency and sustained performance when exposed to cold plasma. The pulsed plasma separation displayed improved structural integrity, and the experimental results …

Training Uav Teams With Multi-Agent Reinforcement Learning Towards Fully 3d Autonomous Wildfire Response, Bryce Hopkins

All Theses

As climate-exacerbated wildfires increasingly threaten landscapes and communities, there is an urgent and pressing need for sophisticated fire management technologies. Coordinated teams of Unmanned Aerial Vehicles (UAVs) present a promising solution for detection, assessment, and even incipient-stage suppression – especially when integrated into a multi-layered approach with other recent wildfire management technologies such as geostationary/polar-orbiting satellites and CCTV detection networks. However, there remains significant challenges in developing the necessary sensing, navigation, coordination, and communication subsystems that enable intelligent UAV teams. Further, federal regulations governing UAV deployment and autonomy pose constraints on real-world aerial testing, creating a disconnect between theoretical research …

Divergence Measures And Aggregation Operators For Single-Valued Neutrosophic Sets With Applications In Decision-Making Problems, Surender Singh, Sonam Sharma

Neutrosophic Systems with Applications

Single-valued neutrosophic sets (SVNSs) facilitate the representation of uncertain information more extensively than conventional methods. The study of divergence measures of SVNSs is important due to their applications in different areas like multi-criteria decision-making (MCDM), pattern recognition, cluster analysis, machine learning, etc., In this paper, we introduce a divergence measure for SVNSs. The suggested divergence measure is applied to cluster analysis for the classification of imprecise data. For establishing the reasonability and advantage of the suggested divergence measure in a clustering problem over the existing measures, a comparative assessment is also presented. Furthermore, we introduce, an inferior ratio method for …

Path-Choice-Constrained Bus Bridging Design Under Urban Rail Transit Disruptions, Yiyang Zhu, Jian Gang Jin, Hai Wang

Research Collection School Of Computing and Information Systems

Although urban rail transit systems play a crucial role in urban mobility, they frequently suffer from unexpected disruptions due to power loss, severe weather, equipment failure, and other factors that cause significant disruptions in passenger travel and, in turn, socioeconomic losses. To alleviate the inconvenience of affected passengers, bus bridging services are often provided when rail service has been suspended. Prior research has yielded various methodologies for effective bus bridging services; however, they are mainly based on the strong assumption that passengers must follow predetermined bus bridging routes. Less attention is paid to passengers’ path choice behaviors, which could affect …

Fuel-Saving Route Planning With Data-Driven And Learning-Based Approaches: A Systematic Solution For Harbor Tugs, Shengming Wang, Xiaocai Zhang, Jing Li, Xiaoyang Wei, Hoong Chuin Lau, Bing Tian Dai, Binbin Huang Huang, Zhe Xiao, Xiuju Fu, Zheng Qin

Research Collection School Of Computing and Information Systems

In recent years, there are trends toward cleaner port environments through enforcement by imposed legislation. Transit optimisation of fuel-based port service boats like harbour tugs has emerged as a critical task to reduce fuel consumption and carbon emission. In this paper, an innovative learning-based method, comprising a Reinforcement Learning (RL) model together with a fuel consumption prediction model, was proposed to formulate fuel-saving transit routes. Firstly, an ensemble model is established by combining a Long Short-Term Memory (LSTM) model with a Multilayer Perceptron (MLP) model, predicting fuel use based on tugboat movement and environment factors. Subsequently, an innovative RL based …

Enabling Sustainable Freight Forwarding Network Via Collaborative Games, Pang Jin Tan, Shih-Fen Cheng, Richard Chen

Research Collection School Of Computing and Information Systems

Freight forwarding plays a crucial role in facilitating global trade and logistics. However, as the freight forwarding market is extremely fragmented, freight forwarders often face the issue of not being able to fill the available shipping capacity. This recurrent issue motivates the creation of various freight forwarding networks that aim at exchanging capacities and demands so that the resource utilization of individual freight forwarders can be maximized. In this paper, we focus on how to design such a collaborative network based on collaborative game theory, with the Shapley value representing a fair scheme for profit sharing. Noting that the exact …

Frameworks For The Techno-Economic Assessment Of Membrane-Based Bioprocessing Platforms, Juan Jose Romero Conde

All Dissertations

This dissertation describes developing and implementing computational frameworks for simulating and optimizing purification processes in the biopharmaceutical industry. The framework performs techno-economic analyses to establish value propositions for new process alternatives, especially membrane technologies. Initially, the focus is developing a framework capable of simulating monoclonal antibody (mAb) capture using membrane and resin media in multi-column chromatography (MCC) platforms for continuous manufacturing. Subsequently, the impact of capture MCC is compared against other intensification strategies in established mAb manufacturing facilities. Finally, the framework application expands to simulate the purification of adeno-associated virus (AAV) vectors for gene therapy.

Chapter 2 details the framework …

Understanding And Tuning Magnetism In Van Der Waals-Type Metal Thiophosphates, Rabindra Basnet, Jin Hu

Physics Faculty Publications and Presentations

Over the past two decades, significant progress in two-dimensional (2D) materials has invigorated research in condensed matter and material physics in low dimensions. While traditionally studied in three-dimensional systems, magnetism has now been extended to the 2D realm. Recent breakthroughs in 2D magnetism have attracted substantial interest from the scientific community, owing to the stable magnetic order achievable in atomically thin layers of the van der Waals (vdW)-type layered magnetic materials. These advances offer an exciting platform for investigating related phenomena in low dimensions and hold promise for spintronic applications. Consequently, vdW magnetic materials with tunable magnetism have attracted significant …

Cubic Soft Ideals On B-Algebra For Solving Complex Problems: Trend Analysis, Proofs, Improvements, And Applications, Muhammad Saeed, Hafiz Inam Ul Haq, Mubashir Ali

Neutrosophic Systems with Applications

In this paper, we introduce the concepts of cubic soft (CS) algebra, CS o-subalgebra, and CS ideals within the framework of B-algebra. We provide comprehensive characterizations of these new structures, elucidating their unique properties and interrelationships. Specifically, we present detailed conditions under which a CS subalgebra can be classified as a closed CS ideal. Our analysis explores the intricate relationships among closed cubic soft ideals, cubic soft subalgebras, and cubic soft o-subalgebras. By doing so, we aim to provide a deeper understanding of how these structures interact and coexist within the broader context of B-algebra The findings offer significant insights …

A Real-Time Iot-Based Data Acquisition And Monitoring System For Photovoltaic Applications, Adam Barbosa, Hamza Mubarak, Fazel Mohammadi, Mohammad J. Sanjari, Mehrdad Saif

Electrical & Computer Engineering and Computer Science Faculty Publications

The transition to low-carbon energy systems, driven by climate change and fossil fuel scarcity, highlights technologies, such as Photovoltaic (PV) technology, for sustainable energy generation. This paper focuses on enhancing the efficiency of PV monitoring systems by leveraging Internet of Things (IoT) technology for accurate and real-time monitoring of essential parameters, such as voltage, current, and output power. Significant gaps in cost-effective and reliable IoT integration for PV monitoring are addressed, with an emphasis on predictive modeling. In this regard, a low-cost real-time IoT-based data acquisition and monitoring system for PV systems, as a proof of concept for future endeavors …

Smart Automatic Modal Hammer Predictor–Corrector Approach For Accurate Excitation Of Dynamical Systems, Mohammad Nasr

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

This research introduces an innovative solution that revolutionizes the study of linear and nonlinear dynamical systems—a smart automatic modal hammer. With its affordability and intelligent capabilities, this automatic modal hammer becomes an invaluable tool for research and industry, enabling repeatable strikes with precise force control. This system's significance becomes particularly evident when studying nonlinear systems, which heavily rely on the excitation level for their dynamics. By offering a cost-effective design this proposed system proves to be robust in accelerating research on nonlinear dynamics, providing researchers with an efficient and accessible means to delve deeper into these complex systems. The proposed …

Studies Of Exotic Electronic, Optical, And Electrochemical Properties In Nanoparticle Assembly And Graphene, Jay Min Lim

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

It is well known that exotic properties and phenomena emerge as structural dimensions shrink to nanoscales. We self-assembled one-dimensional chains of gold nanoparticles in solution and quantified the growth process by monitoring the redshift of localized surface plasmon resonance (LSPR). Curiously, the redshift stopped while the chains continued to rearrange as manifested by gradual reduction in the LSPR peak. Using electromagnetic simulations, we quantitatively explained the phenomena as a rapid “addition-polymerization” followed by a sharp transition to “condensation-process.” Next, recognizing the significant electric field enhancement in the interparticle gap, a photoluminescent-active Eu³⁺ ion was used to probe Surface-Enhanced Photoluminescence …

Physics-Informed Machine Learning Methods For Inverse Design Of Multi-Phase Materials With Targeted Mechanical Properties, Yunpeng Wu

All Dissertations

Advances in machine learning algorithms and applications have significantly enhanced engineering inverse design capabilities. This work focuses on the machine learning-based inverse design of material microstructures with targeted linear and nonlinear mechanical properties. It involves developing and applying predictive and generative physics-informed neural networks for both 2D and 3D multiphase materials.

The first investigation aims to develop a machine learning method for the inverse design of 2D multiphase materials, particularly porous materials. We first develop machine learning methods to understand the implicit relationship between a material's microstructure and its mechanical behavior. Specifically, we use ResNet-based models to predict the elastic …

Effortless Mindfulness Toolkit: Easy Meditation Scripts To Begin Each Class., Brett Whysel

Open Educational Resources

The Effortless Mindfulness in the Classroom Toolkit is an open educational resource designed to create happier classrooms, boost student engagement, and foster a sense of community through brief, effective mindfulness exercises. This comprehensive toolkit provides educators with everything they need to seamlessly integrate mindfulness practices into their teaching routines, regardless of prior experience. The toolkit includes introductory slides, 15 ready-to-use meditation scripts, and accompanying audio recordings, covering a variety of mindfulness techniques such as focused breathing, body scans, and loving-kindness meditations. Each meditation is paired with a reflective prompt to deepen student engagement and reinforce the benefits of mindfulness. Additionally, …

Segac: Sample Efficient Generalized Actor Critic For The Stochastic On-Time Arrival Problem, Honglian Guo, Zhi He, Wenda Sheng, Zhiguang Cao, Yingjie Zhou, Weinan Gao

Research Collection School Of Computing and Information Systems

This paper studies the problem in transportation networks and introduces a novel reinforcement learning-based algorithm, namely. Different from almost all canonical sota solutions, which are usually computationally expensive and lack generalizability to unforeseen destination nodes, segac offers the following appealing characteristics. segac updates the ego vehicle’s navigation policy in a sample efficient manner, reduces the variance of both value network and policy network during training, and is automatically adaptive to new destinations. Furthermore, the pre-trained segac policy network enables its real-time decision-making ability within seconds, outperforming state-of-the-art sota algorithms in simulations across various transportation networks. We also successfully deploy segac …

Experimental And Computational Investigation Of Green Laser Propagation Through Turbulent Medium In A Water Tank, Richard Owusu Adansi

Open Access Theses & Dissertations

Turbulence medium poses significant challenges to the propagation of laser beams, impacting applications such as free-space optical communication, remote sensing, and laser weapons systems. Therefore, comprehending and mitigating turbulence effects are vital for enhancing the performance of these systems. Analysis of a strong turbulence impact on electromagnetic wave propagation requires extensive knowledge of the Earth's atmospheric and Oceanic phenomena and Maxwell's electromagnetic theory of light as a propagating wave of electric and magnetic fields. Optical systems' propagation often encounters Strong Turbulence, causing interference and diffraction. Nonetheless, light propagation through randomly fluctuating media has been an exciting and active area of …

Optimization Of Customer Service And Driver Dispatch Areas For On-Demand Food Delivery, Jingfeng Yang, Hoong Chuin Lau, Hai Wang

Research Collection School Of Computing and Information Systems

With the rapid development and popularization of mobile and wireless communication technologies, on-demand food delivery (OFD) platforms have been able to connect restaurants, customers, and drivers in real time, drastically changing dining and food delivery services. Motivated by the critical need for supply and demand management in the on-demand food delivery market, we focus on the optimization of customer service area and driver dispatch area for on-demand food delivery services. Specifically, for each restaurant, the platform needs to decide the (1) customer service area (CSA), i.e., the surrounding area within which customers can see the restaurant’s information and order food …

Enhancing Fuel Injection System Reliability Through Weibull Family Functions Analysis, Ali Nouri Qarahasanlou, Abbas Barabadi, Meisam Saleki, Ali Rahimazar, Parisa Rezakhania, Masoume Gholamia

Journal of Sustainable Mining

The efficient operation of heavy machinery is crucial to the success of mining and civil construction operations. To guarantee this performance, equipment performance is assessed using the Reliability Index, which analyzes failures to study the ability of a system to carry out its intended functions under predetermined conditions. On the other hand, the failure rate and operational environmental condition (such as management decisions, maintenance performance, etc., that are defined as “risk factors”) over the life cycle of industrial systems pose a significant challenge to reliability analysis. This paper proposes an approach to address these challenges by extending Weibull family functions …

Chemical Recycling Of Bio-Based Polyurethane Foams: Evaluating Bio-Based Glycols In Comparison To Petroleum-Based Glycols, Anirudh Thorbole Mr.

Electronic Theses & Dissertations

The paradigm shift towards bio-based polyurethane foams (bio-PUF) has significantly increased post-consumer waste. To address this issue, this research represents a novel approach to enhance sustainable development in the recycling industry by replacing traditional petroleum-based glycols with sustainable bio-based alternatives. This study explores the glycolysis of bio-PUF using bio-based SG-522 glycol and polyethylene glycol (PEG) for comparison. The findings from this research as outlined, reveal no significant differences in depolymerization time between the two glycols, achieving proper depolymerization and high recovery yields of over 95% after solvent purification. Comprehensive FT-IR and NMR analyses confirmed the successful degradation of bio-PUF and …

Secondary Electron Yield Of Metals, Alloys, And Metal Oxides From First Principles Based Monte Carlo Simulations, Raul E. Gutierrez

Electrical and Computer Engineering ETDs

Density Functional Theory (DFT) based Monte Carlo (MC) simulations of the Sec-
ondary Electron Yield (SEY) of metals, alloys, and metal oxides are performed to
find material properties that could help reduce or influence the multipactor effect.
In order to accurately model the SEY of materials, knowledge of the frequency- and
momentum-dependent Energy Loss Function (qDepELF) is required. The qDepELF
is difficult to determine from experiment; however, it can be calculated from first
principles. The DFT-MC approach for simulating the secondary electron genera-
tion, propagation, and emission processes is described herein. Material properties,
which are calculated using DFT and used …

Effect Of Aging Temperature On Properties Of Sealant Under Field Construction Conditions, Liu Hanchao, Teng Xinhua, Zhang Jingyan, Zhang Kaihua, Lin Hui

Journal of China & Foreign Highway

In order to study the influence of short-term aging temperature on the properties of sealant,a sealant was prepared,and field construction conditions were simulated.The properties of the sealant before and after short-term aging at 180‒220 ℃ were tested.The viscoelastic properties,physicochemical properties,and microstructures of the sealant were studied,and the mechanism of property changes was discussed.The results show that the cone penetration and flow value of the aged sealant decrease,while the softening point and elastic recovery rate increase.Aging at high temperature (>180 ℃) for a short time and low temperature (160 ℃) for a long time will cause obvious property changes.The tensile …

Experimental Study On Capillary Water‑Holding Characteristics Of Loess Backfill In Ecological Ditches, Nan Yalin, Zhang Xiaoyu, Chen Hong, An Peng, Liu Kui, Camara Ibrahima Kalil

Journal of China & Foreign Highway

The municipal ecological ditches have the basic functions of accumulating water for infiltration in the rainy season and conserving moisture in the dry season.However，the design of loess backfill in ecological ditches is based on no evidence，which often leads to landscape vegetation drowning in the rainy season or dying in the dry season.For this reason，a study was carried out by remoulding loess with a small-size capillary water rise height test，a large-size water-holding characteristic model test，and an unsaturated numerical analysis.The results show that the final capillary water rise height of the soil column can reach 100 cm when the dry density is …

Research On Performance Of Coal Gangue Concrete, Wang Jiliang, Ma Wenhui, Xu Weidong, Lyu Zhigang

Journal of China & Foreign Highway

Coal gangue is an industrial solid waste produced in the process of raw coal mining.It has a large stock and a relatively low utilization rate.Using coal gangue as concrete aggregate can not only solve the environmental pollution caused by coal gangue storage but also make up for the shortage of natural sand and gravel resources，which opens up an effective way for the large-scale utilization of coal gangue.According to the application characteristics of coal gangue as concrete aggregate，the chemical component，mineral composition，and physical properties of coal gangue were systematically analyzed.The influence of coal gangue as aggregate on the working performance，mechanical properties，volume stability，and …

Experimental Study On Shear Performance Of Uhpc‑Nc Interface, Wan Zhiyong, Chen Jianping, He Shaohua, Huang Xu, Sun Xiangdong

Journal of China & Foreign Highway

Ultra-high performance concrete （UHPC） has great application prospects in engineering structure reinforcement.The reliability of the bonding properties at the interface between the new UHPC reinforcement layer and the old concrete structure is critical for ensuring the serviceability of the reinforced structures.To determine the influence of different interface treatments on the bonding properties at the interface between the UHPC and normal concrete （NC），six Z-shaped UHPC-NC bonding specimens were designed，and the bonding properties of the UHPC-NC with three different kinds of interface，namely smooth，chisel，chisel + reinforced，were investigated.In addition，nonlinear finite element models for the concrete interface were established to determine the distribution law of …

Application Of Sequential Quadratic Programming Method In Cable Force Adjustment Of Cable‑Stayed Bridges, Xu Yufeng, Zhu Mengyang, Chen Si, Xie Yunfei

Journal of China & Foreign Highway

When the construction of a cable-stayed bridge enters the completion stage，due to various factors，there is a certain error between the actual alignment and internal force of the structure and the theoretical completion state，and it is usually necessary to adjust the cable force.In order to calculate the cable force adjustment of a cable-stayed bridge in the adjustment stage，a method based on an influence matrix and sequential quadratic programming was proposed to solve the cable force adjustment.A large-span hybrid girder cable-stayed bridge was taken as the background，and the alignment and internal force response values of the structure with varying cable units were …

Protection Design Of Middle Piers Of Overpass Bridges Based On Double Protection Concept, Lyu Sizhong, Wang Xin, Guo Jianmin, Liu Siyuan, Li Yuxin, Yang Fuyu

Journal of China & Foreign Highway

The collision accident types of middle piers of overpass bridges were summarized and analyzed，and it was proven that anti-collision and anti-scratching were two important requirements of pier protection.Then，the new concept of double protection and corresponding technical schemes were put forward.The first protection adopted the way of setting concrete barriers or ship-shaped elevating members on the periphery of the pier to prevent vehicles from impacting the pier，and the second protection used the self-wrapped steel plate or aluminum foam plate to prevent vehicles from scratching the pier.The safety of the pier protection structure schemes was verified by computer simulation and unit test，and …

Research On Yolov 5‑Ganomaly Joint Algorithm For High‑Strength Bolt Detection, Xie Haibo, Zhu Weijun, Zhang Bi2, Zhang Dahai

Journal of China & Foreign Highway

High-strength bolt loosening detection of bridges faces problems such as heavy workload，small targets，many anomalies，and difficult collection.Therefore，this paper proposed a semi-supervised deep learning model，which could obtain the bolt loosening detection model even with a small number of negative samples and solve the problem of unbalanced model training samples.The accuracy of the YOLOv 5-CT model for bolt target detection reached 98.33%.By preprocessing bolt data，the reconstruction ability of bolt images by the Ganomaly model was improved.When the hidden space vector value was 100，the model had the highest SAUC and the best discriminant performance.In the model test stage，the threshold of abnormal fraction was set …

Experimental Study On Effect Of Temperature On Bound Water Adsorption And Deformation Of High Liquid Limit Soil, Zi Yinhui, Shen Xuning, Zhang Hao, Zhang Rui, Li Lu

Journal of China & Foreign Highway

In order to study the effect of temperature change on the bound water content adsorbed by high liquid limit clay and the deformation law of high liquid limit clay embankment，the high liquid limit clay in Hainan Province was selected as the primary research object and compared with the low liquid limit sand in Hunan Province.The effect of temperature on the bound water content adsorbed by high liquid limit clay was explored through a nuclear magnetic resonance test.In addition，the effect of temperature on the deformation of high liquid limit clay embankments was analyzed through the consolidation test with a temperature-controlled consolidometer.The …

Temperature And Strain Development Characteristics Of Tunnel Concrete Based On Double Grating Sensors, Fang Jianping, Zhang Mengxi, Yao Xiaonan

Journal of China & Foreign Highway

In order to better prevent tunnel concrete from cracking，the development law of concrete temperature and strain was studied.Based on the connection project of Sanjiang Middle Road in the Smart New City of Quzhou，a data acquisition system was established to monitor concrete temperature and strain on site.The defects of the traditional method that the temperature and strain monitoring are insensitive，and the monitoring data is discontinuous were overcome.In addition，the high-performance double grating temperature-strain sensor was used to simultaneously monitor the temperature and strain at the same position，and the temperature compensation method was used to overcome the influence of the ambient temperature on …