Engineering Commons^™

Sensitivity Analysis Of Data-Driven Groundwater Forecasts To Hydroclimatic Controls In Irrigated Croplands, Alessandro Amaranto, Francesca Pianosi, Dimitri Solomatine, Gerald Corzo-Perez, Francisco Munoz-Arriola

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In the last decades, advancements in computational science have greatly expanded the use of artificial neural networks (ANNs) in hydrogeology, including applications on groundwater forecast, variable selection, extended lead-times, and regime-specific analysis. However, ANN-model performance often omits the sensitivity to ob- servational uncertainties in hydroclimate forcings. The goal of this paper is to implement a data-driven modeling framework for assessing the sensitivity of ANN-based groundwater forecasts to the uncertainties in observational inputs across space, time, and hydrological regimes. The objectives are two-folded. The first objective is to couple an ANN model with the PAWN sensitivity analysis (SA). The second objective …

Biological Systems Engineering, Asmaa Abdella, Fernando Segato, Mark R. Wilkins

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The present work studied the optimization of aeration rate, agitation rate and oxygen transfer and the use of various batch fermentation strategies for xylanase production from a recombinant Aspergillus nidulans strain in a 3 L stirred tank reactor. Maximum xylanase production of 1250 U/mL with productivity of 313 U/mL/day was obtained under an aeration rate of 2 vvm and an agitation rate of 400 rpm using batch fermentation. The optimum volumetric oxygen transfer coefficient (kLa) for efficient xylanase production was found to be 38.6 h1. Fed batch mode and repeated batch fermentation was also performed with kLa was 38.6 h1. …

Supercritical Carbon Dioxide Based Heat Exchanger On The Martian, Sarah Guinn

Discovery Day - Prescott

The use of supercritical carbon dioxide (sCO2) in power cycles has been fairly new in the last decade. Due to this, there is a lack in research for both terrestrial and extraterrestrial applications. The purpose of this project is to utilize sCO2 as a working fluid and design and optimize a Brayton Cycle based heat exchanger on the Martian surface. Due to the lack of water on Mars, this research will provide a stronger analysis of planetary based drycooling processes in low atmospheric pressure and colder temperatures. We have been conducting an in-depth analysis of the heat exchanger by modeling …

Interactions Between 2d Halide Perovskite Materials And Methylamine, Elizabeth Cutlip

19th Annual Celebration of Undergraduate Research and Creative Activity (2020)

Halide perovskites offer exciting potential as photovoltaic materials and simply as semiconductors. Specifically, their structural tunability has become of greater interest as researchers begin to search for novel ways to tune the materials to achieve improved solar cell stability or to target new applications. One potential technology which halide perovskites could enable is dynamically switchable photovoltaic windows, windows which a user can transition between photovoltaically active (dark) and non-photovoltaic (transparent). We build toward this goal in this work by investigating the intercalation and deintercalation of methylamine gas into 2-dimensional Ruddlesden-Popper phase halide perovskites. As has been shown with methylammonium lead …

Optimization Of Vinyl Flooring Packaging, Devon Holloway, Dominique Donahue, Edafe Oyibo, Fatemeh Mafikouhini

Senior Design Project For Engineers

Mohawk Industries, Inc. is one of the leading flooring manufacturers of the world. Mohawk supplies various types of flooring to various markets around the world like the contiguous United States and Southeast Asia. A significant aspect of Mohawk that allows the organization to supply quality flooring products to various markets around the world is their packaging. Recently however, the company has been experiencing damages to their packages being shipped to Southeast Asia, specifically their vinyl flooring packaging. As a result, this team was created with goal in mind of formulating a solution to eliminate the damaging of vinyl flooring packaging …

Thermal Modeling Of Additive Manufacturing Using Graph Theory: Validation With Directed Energy Deposition, Jordan Severson

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

Metal additive manufacturing (AM/3D printing) offers unparalleled advantages over conventional manufacturing, including greater design freedom and a lower lead time. However, the use of AM parts in safety-critical industries, such as aerospace and biomedical, is limited by the tendency of the process to create flaws that can lead to sudden failure during use. The root cause of flaw formation in metal AM parts, such as porosity and deformation, is linked to the temperature inside the part during the process, called the thermal history. The thermal history is a function of the process parameters and part design.

Consequently, the first step …

Service Provisioning And Security Design In Software Defined Networks, Mohamed Rahouti

USF Tampa Graduate Theses and Dissertations

Information and Communications Technology (ICT) infrastructures and systems are being widely deployed to support a broad range of users and application scenarios. A key trend here is the emergence of many different "smart" technology paradigms along with an increasingly diverse array of networked sensors, e.g., for smart homes and buildings, intelligent transportation and autonomous systems, emergency response, remote health monitoring and telehealth, etc. As billions of these devices come online, ICT networks are being tasked with transferring increasing volumes of data to support intelligent real-time decision making and management. Indeed, many applications and services will have very stringent Quality of …

Theoretical Investigation Of Fundamental Cathode Processes In Metal-02 Batteries, Saurin Hiren Rawal

LSU Doctoral Dissertations

In this thesis we theoretically explore the different fundamental phenomena associated with metal-air batteries (where the metal can be Li, Na or K) using first principles density functional theory. We start by investigating the adsorption of the starting reactants/primary intermediates i.e. metal superoxides and superoxide anion on Au(111) and Au(211). We elucidate the influence of electric fields and the importance of including explicit solvents on the adsorption energy of these intermediates. We show that these effects are considerable and should be included for future reaction modeling of these batteries. Following this we investigate the reaction of M⁺ and O …

Simulation And Verification Of Phase Change Materials For Thermal Energy Storage, Marwan Mosubah Belaed

USF Tampa Graduate Theses and Dissertations

Greenhouse gas (GHG) emissions have a global impact on world economies and the ecosystem. Scientific assessment of GHG emissions is an issue that requires immediate action from key decision-makers and influencers. A comprehensive review of the impact of climate change and its dire consequences on daily life is illustrated in this dissertation. The most common technique to lower GHG emissions in the atmosphere is by switching GHG emission sources to zero-emission sources such as solar energy, wind energy, bioenergy, and geothermal power. Recently, all these technologies have made significant progress in lowering capital operation costs and their cycle efficiencies. This …

Multiphysics Computational Model Of Fluid Flow And Mass Transfer In Aneurysm, Tanja Cupac

Graduate Student Research Symposium

The abdominal aortic aneurysm (AAA) mostly affects men between the ages 65-85 and is very common with more than 3 million cases in the United States per year. AAA is defined as the weakening of the arterial wall producing a blood-filled bulge in the body’s largest blood vessel. AAA is progressive, asymptomatic, and can eventually lead to rupture which is a catastrophic event leading to massive internal bleeding and possibly death. Of the males within this age range, 1-3% will die from this disease. About 75% of AAA cases will be characterized by the development of an intraluminal thrombus (ILT). …

A System Dynamics Model Of Supply-Side Issues Influencing Beef Consumption In Nigeria, Kelechukwu G. Odoemena, Jeffrey P. Walters, Holger Maximilian Kleemann

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

The per capita consumption of beef in Nigeria is reducing amidst a rising population that is dependent on beef as a major source of animal protein. In this paper, a system dynamics (SD) model was developed with the aim of testing exploratory policies aimed at reversing this trend. The simulations of various policy tests showed that, of all the policies tested, having a higher carcass yield seems to be the most efficient solution, but its feasibility faces some steep biological and ecological challenges. However, a combination of policies that cuts across the land–cattle–market nexus is necessary to obtain a consumption …

When Optimal Isn’T Optimal, Robin Burk

Operations Management Presentations

Whether you’re an operations manager, a financial executive, an engineer, or an analyst, chances are you’ve been taught to optimize the outcomes of your decisions. And taken in a vacuum, that makes a good deal of sense. But as the new discipline of complex adaptive networks shows, in our heavily interconnected, interdependent world optimizing can introduce hidden vulnerabilities to surprisingly expensive failures. In this webinar we’ll discuss examples of such failures and identify conditions for which a satisfactory but not optimal solution is the best approach overall.

Multi-Objective Signal Timing Optimal Model For Rural-Urban Fringe Area Intersection, Xiaoyu Zhang, Chunfu Shao

Journal of System Simulation

Abstract: With the acceleration of the urbanization process in our country, the road traffic problems in the urban-rural fringe area are becoming serious. In order to improve the traffic efficiency, environmental benefits and traffic safety, a multi-objective optimal model for signal timing is established under the comprehensive consideration of several factors, such as the delay, capacity, number of stops and vehicle emissions. The genetic algorithm is used to solve the problem. A typical intersection is taken as the example for the analysis and the improved design schemes can be achieved and evaluated by the road traffic simulation. The …

2020 - The Twenty-Fourth Annual Symposium Of Student Scholars

Symposium of Student Scholars Program Books

The full program book from the Twenty-fourth Annual Symposium of Student Scholars, held on April 16, 2020. Includes abstracts from the presentations and posters.

Lightmap-Based Gi Collaborative Rendering System For Web3d Application, Shao Wei, Liu Chang, Jinyuan Jia

Journal of System Simulation

Abstract: For the real-time dynamic lighting rendering in low-end web environment, a view-independent collaborative real-time rendering system is presented. The whole system consists of a cloud renderer which produces the global illumination, a web renderer which computes the local illumination, and a scalable collaboration solution which takes the user behavior into account to adjust the range and frequency of the lighting computation. The cloud renderer computes the lighting data into the Lightmap, streams the Lightmap to the web client. After computing the direct light, the web renderer achieves the global illumination information by Sampling the Lightmap, and shows the …

Research On Modeling And Analyzing Method Of Task-Oriented Network Information System Of Systems, Zhu Tao, Weitai Liang, Songhua Huang, Jieyong Zhang

Journal of System Simulation

Abstract: As the catalyst and fusion agent of the system combat capability in the information age, the network information system of systems has been changing the form of information-based warfare and the mode of combat effectiveness generation. On the basis of studying the concept of the network information system of systems and introducing association mapping rules between tasks and systems, a new modeling and analyzing method of the network information system of systems with two dimensions and four networks, based on super-network and service-oriented characteristics, is proposed. The definitions of services information flow motif delay, the task execution accuracy …

Thinking On Digital Twin For Weapon System, Junhua Zhou, Junjie Xue, Heyu Li, Ji Hang, Tingyu Lin, Guoqiang Shi

Journal of System Simulation

Abstract: The main development process of the digital twin technology is reviewed and its necessity for the weapon system is put forward. The definition and composition of the digital twin for the weapon system is given and its application architecture and key technologies, such as the construction of the digital thread, bi-directional collaborative simulation and control, intelligent autonomous evolution, digital twin operation support based on the container-simulation-cloud, et al, are analyzed. The preliminary research and practice of some key technologies is expounded, and the future research directions are summarized and looked forward to.

Modeling And Propeller Location Optimization For Diving Propeller Vehicle, Jianjun Zhang, Yang Bing, Jinhui Wu, Yan Qiang

Journal of System Simulation

Abstract: Focus on the rapid physical exertion and the poor flexibility of diving propeller vehicle, a wearable diving propeller equipped with buoyancy control devices is proposed, and the position of the propeller in the device is optimized. The human body structure is regarded as a rigid body to establish a spatial 6-degree-of-freedom motion equation, and its surrounding hydrodynamic performance is analyzed. The hydrodynamic parameters in the model are obtained based on the FLUENT. The propeller position optimization model based on the minimum external force of rectilinear diving and slewing motions is established. The optimization results demonstrate that the optimized …

Research On Image Description Method Based On Neural Network, Kong Rui, Xie Wei, Lei Tai

Journal of System Simulation

Abstract: The automatic recognition and automatically describing image content is an important research direction to the artificial intelligence to connect the computer vision and the natural language processing. A method of describing the image content is proposed to generate the natural language by using the deep neural network model. The model consists of a convolutional neural network (CNN) and a recurrent neural network (RNN). The CNN is used to extract features of the input image to generate a fixed-length feature vector, which initializes the RNN to generate the sentences. Experimental results on the MSCOCO image description dataset show the syntactic …

Multi-Objective Dynamic Programming Algorithm Of Energy-Efficient Scheduling For Tow-Train, Xinyan Zhang, Yuqing Zhou

Journal of System Simulation

Abstract: To balance the performance and energy consumption of the mixed-model assembly lines effectively, a multi-objective energy-saving scheduling method for the tow-train is proposed. The energy-saving objective is introduced into the traditional material handling scheduling model for the tow-train and a multi-objective mixed integer programming model is constructed with two objective functions of minimizing the maximum line-side inventory and the total energy consumption. A forwards multi-objective dynamic programming based on the time window and dominance rules is presented to obtain the Pareto solutions: the definition for new states is given to obtain the Markov property, the time window and dominance …

Design Of Space-Based Surveillance Distributed Simulation System For Space Targets, Zhang Yang, Qingbo Gan, Yuan Hong, Jiangliang Fu, Chengming Sun

Journal of System Simulation

Abstract: Following the wide application of the HLA in the aerospace system simulation, the space-based surveillance distributed simulation system for the space targets based on the HLA is designed. In the infrastructure design level, the hierarchical structure including data layer, model layer and mission layer are designed. In the system design level, the simulation control members, space-based surveillance member, space target member, optical payload member, and visual simulation member are divided and confirmed. The orbit dynamics and maneuvering model, attitude dynamics and control model, payload pointing and optical imaging model are established. In system implement level, the …

One Design Mode Of Highly Configurable Modular Simulation System, Chunsheng Hu, Chengdong Xu, Penfei Zhang

Journal of System Simulation

Abstract: The computer simulation technology is an essential verification way to the design, construction and application optimization of the modern complex system. Following the continuous growing complexity of the system, the higher requirement on the configurability of the simulation system is needed to face the rapidly change. Based on the analysis on the configurability and some coupling factors with the adverse effect, a design mode of highly configurable and open and easy to expend modular simulation system is proposed. The results show that, despite the cost of some real-time performance, the design mode can realize the high configurability of the …

Modeling And Simulation Of Locating Water Resources For Forest Fire Extinguishing, Guoxiong Zhou, Li Tong, Aibin Chen, Mingfang He

Journal of System Simulation

Abstract: At the time of the forest fire, the effective water resource position is a good assistance to the firefighters to put out the fire. Taking a state-owned tree-farm, Huangfeng Bridge as an example in You Xian, an approach is proposed to optimally locate and determine the water resources to extinguish the forest fires, which uses the barycenter of a Weighted Voronoi Diagram and is generated dynamically via Cellular Automata and locally optimized by Alternative Location and Allocation algorithm. In order to reduce the low ratio impact of the water resource to the high fire risk areas, a barycenter model …

Cost-Efficiency Analysis Of Weapon System Portfolios For Effect Based Operation, Zhong Lin, Mingan Tong, Zhang Jian, Jianhai Liang

Journal of System Simulation

Abstract: In considertion of the cost-efficiency analysis of weapon system mainly for the target based operation, the uncertainties about preferences and possible interactions of different weapon systems, a cost-efficiency analysis method weapon system portfolios for effect based operation is presented. The framework of weapon system assignment for effect based operation is presented, the Bayesian network is used to build up the connection between effects and targets, and the cost-efficiency analysis model based on robust portfolio optimization is carried out. In view of the combinatorial explosion, the approximation algorithm based on the Tchebycheff norm and the linear integer programming is proposed …

System Dynamics And Multi-Agent Simulation Research On Ground Combatpersonnel Attrition, Xiaoxiong Hao, Jianwei Ma, Zhaohui Huang, Yungui Wang

Journal of System Simulation

Abstract: In order to study the law of the combat personnel attrition and guide the military medical logistics support, the relevant researches are systematically sorted out and the key questions are clarified. Based on Lanchester equation theory, a system dynamics model of the combat attrition process is established, and the consistency between the model conclusion and the historical experience is analyzed. A multi-agent model of the combat attrition process is also constructed, and the advantages and disadvantages of the two models are analyzed. The main conclusion is that the theoretical model’s outcomes of combat attrition are relatively consistent with the …

Modeling Method Of Emergency Response Based On Internal And External Areas Of Disaster Zone, Liang Wei, Yanyan Huang, Jianyu Wang

Journal of System Simulation

Abstract: The insufficient ability of the rescuers and the insufficient self-rescue ability of the victims are the two main reasons of the low efficiency in some conventional event emergency. An emergency response model which combines the rescue ability and the self-rescue ability is presented. The division of the internal and the external system in the disaster field is defined, the basic structure of the model and the emergency response process characteristics are described. MAS (multi-agent system) is used to describe the law of the emergency behavior. The synergistic rescue effect is simulated through an imaginary case. The results show that …

Simplification And Compression Service Construction Of 3d Model For Complex Products, Junjie Xue, Guoqiang Shi, Junhua Zhou, Huiyang Qu, Tao Luan, Ruiying Pu

Journal of System Simulation

Abstract: A simplification and compression (S&C) service construction method of the 3D model for the complex products is proposed. An improved method of the model data export and spatial index generation is adopted to preserve the assembly tree and label information of the model in the process of model S&C. An adaptive mesh simplification algorithm based on the mesh density is designed and implemented, and the meshes can be simplified adaptively on condition of satisfying the requirement of error for the geometric model. And a model data compression algorithm with the high compression ratio and efficiency is adopted to reduce …

Material Discovery And High Throughput Exploration Of Ru Based Catalysts For Low Temperature Ammonia Decomposition, Katherine Mccullough, Pei-Hua Chiang, Juan D. Jimenez, Jochen A. Lauterbach

Faculty Publications

High throughput experimentation has the capability to generate massive, multidimensional datasets, allowing for the discovery of novel catalytic materials. Here, we show the synthesis and catalytic screening of over 100 unique Ru-Metal-K based bimetallic catalysts for low temperature ammonia decomposition, with a Ru loading between 1–3 wt% Ru and a fixed K loading of 12 wt% K, supported on γ-Al2O3. Bimetallic catalysts containing Sc, Sr, Hf, Y, Mg, Zr, Ta, or Ca in addition to Ru were found to have excellent ammonia decomposition activity when compared to state-of-the-art catalysts in literature. Furthermore, the Ru content could be reduced to 1 …

Understanding Individual Color Perceptions Within Print And Digital Media, Morgan Haskins

Honors Theses

Color is a subjective attribute that is seen differently by each individual and this research is intended to build upon the subjective nature of color perceptions. This research aims to determine the effect of subjectivity on print and digital design and of extended gamut printing and effective color management on color perception. The significance of understanding color perception is directly applicable to consumer perception of designs using color. If designers want their brand to be immediately recognized and be positively accepted, they must be able to accurately reproduce their brand colors with little to no color difference and be able …

Time Domain Vertical Dynamics Model Of Electric Vehicle Considering Electric Motor Vibration, Guoying Tian, Pengyi Deng, Shulei Sun, Yiqiang Peng, Haiying Lu

Journal of System Simulation

Abstract: On the basis of considering the electric motor vibration, a time domain vertical dynamics model of the electric vehicle with 11 DOF is built, and the road roughness input model and the numerical method are given. Aiming at an electric passenger vehicle, the basic characteristics of the typical vehicle dynamics responses under the condition of the impulse and random road roughness inputs are calculated, the influence of the different mount stiffness, damping and motor mass on the motor and the vehicle vibration is analyzed under the condition of the impulse input. The results show that the proposed model is …