Engineering Commons^™

Development Of Models For The Velocity-Pressure Gradient Correlations In Incompressible Wall-Bounded Planar Turbulent Flows Using Multiple Linear Regression, Juampablo E. Heras Rivera

Mechanical Engineering ETDs

In this thesis, the multiple linear regression method is applied to clarify terms and their coefficients in data-driven models for velocity/pressure-gradient (VPG) correlations in the Reynolds stress transport equations. Additionally, a method for developing universal linear models for the VPG correlations with unchanging coefficients when complex conditions arise in a flow is introduced. The generated models were assessed using residual analysis to ensure an appropriate level of accuracy. Data from direct numerical simulation in an incompressible fully-developed turbulent channel flow at Re_tau = 392 with an adverse pressure gradient is used in the study as the data source.

A High-Strength Precipitation Hardened Cobalt-Free High-Entropy Alloy, Matthew Luebbe, Jiaqi Duan, Fan Zhang, Jonathan Poplawsky, Hans Pommeranke, Maalavan Arivu, Andrew Hoffman, Mario F. Buchely, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Recent Studies on Precipitation-Hardened High-Entropy Alloys (HEAs) Demonstrate their High Strength and Thermal Stability, Making Them Promising Materials for High-Temperature Structural Applications Such as Nuclear Reactors. However, Many Existing HEAs Contain Cobalt (Co), Which is Unsuitable for Nuclear Applications Because of the Long-Term Activation Issue of Co. Co is Also Expensive and Considered a Critical Material for Other Applications. Therefore, It is Desired to Exclude Co from the Composition. a Co-Free (Fe_0.3Ni_0.3Mn_0.3Cr_0.1)88Ti₄Al₈ HEA Was Developed and Studied in This Work. in Contrast to Previous Co-Free HEAs, This Alloy is …

Deficit Irrigation Management For Irrigated Corn In Nebraska: Economically Viable?, Lia Nogueira, Cory Walters, Emily O'Donnell, E. Wesley F. Peterson, Suat Irmak

Cornhusker Economics

In this study we determine the economic value of deficit irrigation management using both technological and methodological advancements. The use of soil moisture probes represents the technological improvement. We provide improvements in the methodology as follows. Regarding data, we employ a field-size study, instead of plots, where the irrigation decision is determined by the moisture level in the soil measured through a soil moisture probe. Regarding the understanding of the yield response to water, although we examine the commonly used quadratic function, we improve upon this specification by also examining an alternative response function, the linear response stochastic plateau. Our …

Research On Workshop Logic Modeling And Simulation Based On Finite State Machine, Mingyuan Liu, Jiaxiang Xie, Hao Wu, Jianlin Fu, Guofu Ding

Journal of System Simulation

Abstract: Discrete manufacturing is common in aircraft, ships, electronic equipment, automobile and other manufacturing industries. To ensure the correctness and flexibility of the modeling and simulation process of discrete manufacturing workshops, a logical modeling and simulation method for the production process of discrete manufacturing workshop is proposed. Based on the theory of discrete event dynamic systems and finite-state machines, the attributes and behaviors of the key elements of the discrete manufacturing workshop are abstracted into a unified logic model, and the function of various elements are realized through inheritance. A production process simulation algorithm is designed for the unified model …

Dynamics Modeling And Online Prediction Of Energy Consumption Of Discrete Manufacturing System, Wei Chen, Yan Wang, Zhicheng Ji

Journal of System Simulation

Abstract: Aiming at the traditional energy consumption modeling methods of discrete manufacturing system being difficult to adapt to the complexity and variability of working conditions, an online dynamic energy consumption modeling method based on real-time data is proposed. The energy consumption affecting factors are determined by analyzing the operation mechanism of the discrete manufacturing system and equipment. An online sequential extreme learning machine algorithm that can dynamically adjust the number of hidden layer nodes is proposed to construct the energy consumption model. The real-time data can update the model quickly. Bernstein's inequality is introduced to improve the model data screening …

Research Progress Of Opponent Modeling Based On Deep Reinforcement Learning, Haotian Xu, Long Qin, Junjie Zeng, Yue Hu, Qi Zhang

Journal of System Simulation

Abstract: Deep reinforcement learning is an agent modeling method with both deep learning feature extraction ability and reinforcement learning sequence decision-making ability, which can make up for the depleted non-stationary adaptation, complex feature selection and insufficient state-space representation ability of traditional opponent modeling. The deep reinforcement learning-based opponent modeling methods are divided into two categories, explicit modeling and implicit modeling, and the corresponding theories, models, algorithms and applicable scenarios are sorted out according to the categories. The applications of deep reinforcement learning-based opponent modeling techniques on different fields are introduced. The key problems and future development are summarized to provide …

Adaptive Correction Tracking Algorithm Based On Detector And Locator Fusion, Yecai Guo, Cheng Liu

Journal of System Simulation

Abstract: In order to avoid tracking failure caused by occlusion, rotation and other factors in complex dynamic scenes, an adaptive correction tracking algorithm based on detector and locator fusion is proposed. The locator trains a convolutional neural network (CNN) filter for location estimation by extracting the deep features of target. The CNN filter adds two layers of shallow features to the three layers of the convolution features of original CF2 algorithm, which enhances the extraction of target texture information. The detector calculates the confidence score by extracting histogram of oriented gradient(HOG) feature of target and combining the context information. …

Cross-Domain Text Sentiment Classification Based On Auxiliary Classification Networks, Na Ma, Tingxin Wen, Xu Jia, Xiaohui Li

Journal of System Simulation

Abstract: To align exactly the texts with same sentiment polarities of source and target domains, and to enlarge the feature difference of different sentiment texts as much as possible, a domain adaptation model with weighted adversarial networks is proposed. A new structured classification network consisting of a main classification network and an auxiliary classification network is proposed, in which the main classification network is used to perform supervised learning on the labeled texts of the source domain, and the auxiliary classification network is used to improve the distinguishability of the text features. A calculation method of multiple adversarial network weights …

Trajectory Control Of Crawler Robot Based On Lstm And Smc, Dongyang Liu, Wenwen Zha, Liang Tao, Cheng Zhu, Lichuan Gu, Jun Jiao

Journal of System Simulation

Abstract: Trajectory tracking is an important part of mobile robot control technology and possesses prospect. Highly nonlinear dynamic characteristics are the main obstacles of controller design. A SMC method based on LSTM and quasi-sliding mode is proposed. The kinematics model and dynamics model of the tracked vehicle are given, and the sliding mode control system is established based on the dynamics model. LSTM network based on deep learning method is designed to control and compensate the unknown interference items, reduce the influence of external interference, and reduce the tremor phenomenon by combining the advantages of LSTM network and quasi-sliding …

Multi-Agent Cooperative Combat Simulation In Naval Battlefield With Reinforcement Learning, Ding Shi, Xuefeng Yan, Lina Gong, Jingxuan Zhang, Donghai Guan, Mingqiang Wei

Journal of System Simulation

Abstract: Due to the rapidly-changed situations of future naval battlefields, it is urgent to realize the high-quality combat simulation in naval battlefields based on artificial intelligence to comprehensively optimize and improve the combat effectiveness of our army and defeat the enemy. The collaboration of combat units is the key point and how to realize the balanced decision-making among multiple agents is the first task. Based on decoupling priority experience replay mechanism and attention mechanism, a multi-agent reinforcement learning-based cooperative combat simulation (MARL-CCSA) network is proposed. Based on the expert experience, a multi-scale reward function is designed, on which a naval …

I-Nicemo Enhanced Algorithm Based On Intersection Angel Geometry, Yifan He, Yulin He, Yongda Cai, Zhexue Huang

Journal of System Simulation

Abstract: To exactly determine the number of cluster centers and correctly identify the candidate cluster centers, an I-niceMO enhanced(I-niceMOEn) algorithm based on intersection angel geometry is proposed. As many distributions of intersection angles and distances as possible between observation points and data points are utilized to recognize the candidate cluster centers to avoid the neglection of cluster centers. The spectral clustering algorithm is used to automatically merge the candidate cluster centers according to the eigenvalues of Laplacian matrices. The number of final cluster centers is determined by the number of merged candidate cluster centers. The number of clusters can be …

Bottleneck Drift Fluctuation Analysis Of Discrete Remanufacturing System Under Disturbance, Yongzhang Zhou, Yan Wang, Zhicheng Ji

Journal of System Simulation

Abstract: Considering comprehensively the influence of each production process on the bottleneck degree of discrete remanufacturing system, the interval bottleneck index matrix is established by collecting data repeatedly in the observation stage to obtain the comprehensive bottleneck index of equipment, which is used as the identification basis. Aiming at the volatility of bottleneck drift in the uncertain environment of discrete remanufacturing system, based on the interval bottleneck index matrix and comprehensive bottleneck index, a theoretical method of visual dynamic analysis including system sensitivity coefficient, machine sensitivity coefficient and bottleneck drift judgment model is established. The discrete event simulation case is …

Shared Subnet Synthesis And Application Of Object-Oriented Pres Net, Chuanliang Xia, Maibo Guo, Zhuangzhuang Wang, Yan Sun

Journal of System Simulation

Abstract: Focus on embedded system modeling, a solution to obtain a synthesized net via the shared subnet of an extended Petri net is proposed. Object-oriented technology and Petri net-based representation for embedded system (PRES net) are merged to obtain an object-oriented PRES net (OOPRES net). A method of synthesized operation of the shared subnet of OOPRES net is proposed, and the preservation of the liveness and boundedness of synthesized net system is studied. Taking the modeling analysis of intelligent transportation system as an example, the effectiveness of the synthesized method is verified. The method can provide an effective way for …

Construction Technology Of Hand Posture Dataset Based On Virtual Simulation Method, Jiaxin Chen, Guohui Zhou, Jianbai Yang

Journal of System Simulation

Abstract: Hand posture is an important carrier of human-computer interaction, and the acquisition and recognition of posture information largely depends on the hand posture dataset. Existing datasets can be divided into two categories, real datasets and synthetic datasets. As real data is limited by equipment, environment, and other factors, the classification of hand posture is insufficient and the annotation is mixed with a lot of manual errors. The existing synthetic data can solve the data scale problem of real data, but the synthetic hand posture volume is limited and with some unreasonable kinematic postures of which the data form are …

Research On Unmanned Swarm Combat System Adaptive Evolution Model Simulation, Zhiqiang Li, Yuanlong Li, Laixiang Yin, Xiangping Ma

Journal of System Simulation

Abstract: Aiming at the fact that the intelligent unmanned swarm combat system is mainly composed of large-scale combat individuals with limited behavioral capabilities and has limited ability to adapt to the changes of battlefield environment and combat opponents, a learning evolution method combining genetic algorithm and reinforcement learning is proposed to construct an individual-based unmanned bee colony combat system evolution model. To improve the adaptive evolution efficiency of bee colony combat system, an improved genetic algorithm is proposed to improve the learning and evolution speed of bee colony individuals by using individual-specific mutation optimization strategy. Simulation experiment on …

Atmospheric Corrosion Simulation Of Air Conditioning Heat Exchanger In Service Under Marine Environment, Huang Peng, Jun Wang, Li Qi, Zhidong Wu

Journal of System Simulation

Abstract: Aiming at the performance degradation of airconditioner heat exchanger caused by serious corrosion under marine environment, an atmospheric corrosion simulation method is studied to analyze and predict the influence on corrosion conditions of marine environment and working condition of air conditioner heat exchanger. From the acquisition of material parameters, the construction the model and the setting of boundary conditions, the atmospheric corrosion simulation process of air conditioner heat exchanger in service under marine environment is systematically introduced, and a method to verify the accuracy of the simulation model by using an artificially accelerated environmental test chamber is provided. From …

Validation And Development Of Top-Down Illumination For Optofluidic Biosensors, Matthew Marley Hamblin

Theses and Dissertations

Lab-on-a-chip devices are changing the way that medical testing is performed by allowing rapid testing with small samples. Optofluidic biosensors are a type of lab-on-a-chip device that use light excitation on a fluid sample. One such application of an optofluidic biosensor is a device that can detect antibiotic resistant bacteria by combining DNA from a sample with fluorescent beads, flowing that sample through a hollow channel, and shining laser light on the channel. If the bacteria tested for is present, the fluorescent beads will give off photons that can be detected as a positive signal. The main method for illumination …

Quantifying And Managing Anthropogenic And Drought Influences On Instream Temperatures, Abbygael Johnson

Student Research Symposium

The western US is currently experiencing effects of one of the worst droughts in 1200 years. These effects are evident in our rivers, as shown by broad scale reductions in baseflow. This lack of runoff combined with growing demands has resulted in the overallocation of the water contained within our rivers and reservoirs. Water temperature is the key factor in many biological, chemical, and physical processes, making it critical to the health of ecosystems . River temperatures are a function of many factors including weather and tree canopy, but also instream flow volumes and water residence time. When instream flows …

Understanding The Role Of A Putative Type I Polyketide Synthase In Chlorflavonin Biosynthesis, Ammar Mussaji

Student Research Symposium

Flavonoids are an important class of plant secondary metabolites with a variety of biological functions in the development processes of hosts. These molecules have also shown health-benefiting properties such as antioxidant and anti-inflammatory activities. As such, they are commonly used as pharmaceuticals and nutraceuticals. In plants, flavonoids are assembled through a type III polyketide synthase (PKS) and associated tailoring enzymes such as hydroxylase and glycosyltransferase. Some filamentous fungi also produce flavonoids, such as chlorflavonin from Aspergillus candidus. Chlorflavonin is a novel halogenated flavonoid found in nature reported to possess antifungal and anti-tuberculosis activity. Unlike plants, the biosynthetic process of flavonoids …

Glycosylation Of Anti-Tb Agent Chlorflavonin For Combating Mycobacterium Tuberculosis, Jie Ren

Student Research Symposium

More than two billion people were infected by the bacterial pathogen Mycobacterium tuberculosis (Mtb) in 2020. However, during the past 50 years, the first-line (isoniazid, delamanid, and rifampicin) and second-line (capreomycin, streptomycin, and cycloserine) therapies have remained unchanged with disadvantages such as long treatment periods and severe side effects. The slow development of anti-TB drugs cannot combat the fast development of drug resistant M. tuberculosis strains from multidrug-resistant (MDR) into extensively drug resistant (XDR), which further hinders the World Health Organization’s goal to end the global TB pandemic by the year 2035. Flavonoids are a type of natural product with …

Molecular Dynamics Simulations Of Liquid Crystal Elastomers, Nanang Mahardika

Student Research Symposium

This poster summarized the work on the Molecular Dynamics (MD) simulation of nematic Liquid Crystal Elastomers (LCE). The validations of the potential were performed by comparing the density and nematic to isotropic transition temperature. After the validation, the thermal properties of nematic LCE (glass transition temperature) and the spontaneous deformation were computed for different compositions of LCE. The results show that the MD simulation can capture the relatively large spontaneous deformation but obtain the different values of glass transition temperature with that of the experiment. Further studies will be conducted to investigate the influence of the polymerization process on the …

Electric Vehicle Charger Reliability Study, Conner Deppe

Student Research Symposium

The reliability of electric vehicle chargers is critical for the widespread adoption of EVs. To consumers, an indication of charging reliability is the unscheduled downtime of EV charging equipment. Unscheduled downtime brings the need for online EV health monitoring and remaining useful lifetime estimation technology. Though there are many different topologies and configurations for EV chargers, the core processing components remain the same. These components, known as silicon carbide MOSFETs, are important devices that provide better efficiency and power density than their silicon counterparts. In recent years, it is found that device on-resistance is a common indicator used in health …

Molecular Dynamics Simulations Of Liquid Crystal Elastomers, Nanang Mahardika

Student Research Symposium

Molecular Dynamics Simulations of Liquid Crystal Elastomers

Is The Pen Mightier Than The Computer? An Analysis Of Digital Natives’ Preference For Writing Tools, Dylan Ash, Landon Corbett, Jane Harvey, Clarissa Lloyd, Ellie Miller, Lauren Myers, Hannah Potter, William Spence, Mason Bodell, Avery Truman, Anna Tuite, Isabelle Vasquez, Nevaeh Villastrigo

Student Research Symposium

Students in Honors 1320, History of Writing, investigated traditional, college-aged students and their preferred writing implements. Digital Natives--people born after 1980 who grew up with technology--are assumed to prefer digital writing implements such as computers, tablets, and Smartphones. Do they really tend to use digital implements, or do they use analog instruments such as pens and pencils? To find out, the researchers designed a Qualtrics survey to ask students about their use of digital and analog writing tools. A second data source were essays on the topic 'My Favorite Writing Implement,' which were analyzed on a spreadsheet, counting each instance …

Does Diet Effect The Brain?, Janna Hart

Student Research Symposium

Short-chain fatty acids are biomolecules produced from bacterial fermentation of dietary fiber in the gut. Short-chain fatty acids are used in the gut to supply energy and reduce inflammation but are also believed to have effects on the brain. While we do not know how short-chain fatty acids affect the brain and behavior, recent research has led to the idea of using dietary changes as a treatment for mental health disorders. In my research, we aimed to visualize where short-chain fatty acids act in the brain with a particular focus on neural immune cells called microglia and the neurons that …

"Challenging The Known." 16th Annual Research Week: Event Proceedings, University Of The Incarnate Word

Excellence Summit (Research Week) Archived Proceedings

Presentations of completed and ongoing research activity conducted by graduate students, undergraduate students, and faculty at University of the Incarnate Word. Includes poster, podium, visual arts, interactive demo, and creative and performing arts presentations. Coordinated and presented by the Office of Research and Graduate Studies.

One-Dimensional And Two-Dimensional Simulations Of Helical Homopolymers: A Comparative Analysis Of Energy Stabilization And Efficiency, Matthew Hooks, Nathan Roberts, Matthew Williams Ph. D.

Steeplechase: An ORCA Student Journal

The purpose of our work is to analyze the results of a two-dimensional parallel tempering simulation of a coarse-grained helical homopolymer. We aim to measure the efficiency of the simulation and apply this efficiency to the theoretical protein free energy landscape.The stable states for helical homopolymers will be analyzed using the folding funnel theory of free energy landscapes for given polymer configurations. The genesis of each simulation is defined by a randomly configured polymer; as time progresses, the energy of each structure decreases until equilibrium is reached. Data collected after equilibrium is reached is used to understand polymer behavior for …

Neutrosophic Marcos In Decision Making On Smart Manufacturing System, Nivetha Martin, Said Broumi, S. Sudha, R. Priya

Neutrosophic Systems with Applications

Business firms prefer software-based smart manufacturing systems to monitor and supervise all production activities in a decentralized manner. The choice of software decides the degree of manufacturing robustness. This paper proposes a neutrosophic-based MARCOS (Measurement of Alternatives and Ranking according to COmpromise Solution) method of MCDM with single-valued triangular neutrosophic numbers to solve the software selection problem. The proposed neutrosophic method is applied to hypothetical data to test the efficacy of the method. The results obtained using the proposed method are compared with crisp, fuzzy, and intuitionistic data representations, and suitable inferences are acquired. The proposed method has several industrial …

Application Of An Empirical Density Law Via Python For Aqueous Plutonium Nitrate Systems, Tara L. Robertson

Nuclear Engineering ETDs

A predictive density tool has been developed to reduce bias and uncertainty in nuclear criticality safety calculations for aqueous plutonium nitrate systems. Multiple methods to calculate the density were reviewed and an empirical method was selected for use. The selected method was then implemented into a Python tool to calculate the solution density and the atom densities for an MCNP6.2 input file.

The Python tool has been validated and verified against the International Handbook of Evaluated Criticality Safety Benchmark Experiments to predict densities within ± 2.6%. The capability to calculate and utilize densities from this tool is a large improvement …

Calibration And Use Of S3f Sensor For Normal And Shear Stress Measurements In Soil, Hussein Alqrinawi

LSU Master's Theses

Innovative sensors can provide new capabilities to monitor and understand the behavior of soil, rock, and geo-structures and help geotechnical engineers make informed decisions about the construction and maintenance of geo-structures. This study introduced, calibrated, and validated one such sensor, the Surface Stress Sensitive Film (S3F) point sensor, for both normal and shear stress measurements in soil along the soil-structure interface. The measurements of S3F sensor rely on the deformation of an elastic film that is monitored by a floating element embedded in the elastic film. This sensor provides measurements of the 3D deformation of the film which are converted …