Engineering Commons^™

Modeling Overdraft-Driven Nitrate Transport In Shallow Wells For Mitigation And Scenario Planning, Jonathan Cronk

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

In Nebraska, average nitrate concentrations in groundwater have doubled since 1974, making water quality management more important than ever. As droughts, heat waves, and floods become more common climate events, understanding their impacts will be necessary to make informed management decisions. Emerging literature describes that drought correlates to an increase in the concentration of nitrate-N at domestic and irrigation wells, however the relative contributions of the mechanisms thought to be responsible is currently unknown.

This research assessed the impact of recharge and pumping rate changes as two mechanisms affecting nitrate-N concentration during drought, assessed the relationship between well depth and …

A One-Dimensional Analysis Of A Microbial Fuel Cell For Efficient Acetate Removal And Power Density Output, David Rouhani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Microbial fuel cells (MFCs) are electrochemical devices that utilize microorganisms to convert organic matter into electrical energy. MFCs have been discussed to have potential application for sustainable wastewater treatment due to their ability to generate electricity while simultaneously treating contaminated water. To optimize MFC performance, numerical models can be used to understand the complex electrochemical and biological processes occurring in the system. In this study, a numerical model was developed to simulate the performance of MFCs under varying operating conditions and to investigate the performance of a MFC for treating wastewater fuel. More specifically, the MFC was modeled to oxidize …

Simulation And Experiment Of An Intelligent Control Model For The Cleaning Of A Rice-Wheat Combine Harvester, Qing Jiang, Rujing Wang

Journal of System Simulation

Abstract: Modeling and simulation of cleaning intelligent control according to the changes of cleaning loss rate and trash content rate is the focus of research and hot issues of intelligent control of rice-wheat combine harvester. A method for acquiring knowledge of the experts' experience and knowledge is constructed based on the flow chart of cleaning control, and a cleaning intelligent control knowledge base for the intelligent control of the field operation environment based on the production rule is proposed. Based on the principle of human-simulating intelligent control, a knowledge inference algorithm for adaptive selection of cleaning regulation strategy is …

Wind Power Primary Frequency Regulation Simulation Based On Wind Speed Prediction Model, Zhenyu Zhao, Xu Ma, Geriletu Bao

Journal of System Simulation

Abstract: To furtherly improve the accuracy of wind speed prediction, considering the coupled comprehensive features of data internal structure external influencing factors, and the characteristics of wind turbines power, a BP-ARIMA combined prediction model is constructed and the wind speed of wind farms is simulated. Compared with the actual data, the high prediction accuracy of the model is verified. Bases on the curve of typical power characteristic of wind turbine, the optimal configuration of energy storage device capacity and the stability of wind turbine are considered, and the MATLAB-SIMULINK platform is applied to simulate the primary frequency regulation of …

On The Use Of High-Frequency Surface Wave Oceanographic Research Radars As Bistatic Single-Frequency Oblique Ionospheric Sounders, Stephen R. Kaeppler, Ethan S. Miller, Daniel Cole, Teresa Updyke

CCPO Publications

We demonstrate that bistatic reception of high-frequency oceanographic radars can be used as single-frequency oblique ionospheric sounders. We develop methods that are agnostic of the software-defined radio system to estimate the group range from the bistatic observations. The group range observations are used to estimate the virtual height and equivalent vertical frequency at the midpoint of the oblique propagation path. Uncertainty estimates of the virtual height and equivalent vertical frequency are presented. We apply this analysis to observations collected from two experiments run at two locations in different years, but utilizing similar software-defined radio data collection systems. In the first …

Raising Dielectric Permittivity Mitigates Dopant-Induced Disorder In Conjugated Polymers, Meenakshi Upadhyaya, Michael Lu-Díaz, Subhayan Samanta, Muhammad Abdullah, Keith Dusoe, Kevin R. Kittilstved, Dhandapani Venkataraman, Zlatan Akšamija

Electrical and Computer Engineering Faculty Publication Series

Conjugated polymers need to be doped to increase charge carrier density and reach the electrical conductivity necessary for electronic and energy applications. While doping increases carrier density, Coulomb interactions between the dopant molecules and the localized carriers are poorly screened, causing broadening and a heavy tail in the electronic density-of-states (DOS). The authors examine the effects of dopant-induced disorder on two complimentary charge transport properties of semiconducting polymers, the Seebeck coefficient and electrical conductivity, and demonstrate a way to mitigate them. Their simulations, based on a modified Gaussian disorder model with Miller-Abrahams hopping rates, show that dopant-induced broadening of the …

Research On Multi-Objective Optimization Method Based On Model, Jianjun Liu, Guangya Si, Yanzheng Wang, Dachuan He

Journal of System Simulation

Abstract: There is a model-based algorithm for the optimization of multiple objective functions by means of black-box evaluation is proposed. The algorithm iteratively generates candidate solutions from a mixture distribution over the solution space and updates the mixture distribution based on the sampled solutions’ domination count, such that the future search is biased towards the set of Pareto optimal solutions. The proposed algorithm seeks to find a mixture distribution on the solution space so that each component of the mixture distribution is a degenerate distribution centered at a Pareto optimal solution and each estimated Pareto optimal solution is uniformly spread …

Modeling And Simulation Of Wx And Interference Display Of Aew Radar Simulator, Xiaojun Chu

Journal of System Simulation

Abstract: Three are two bottlenecks during training: irregular form display simulation of weather target and display simulation of electromagnetic interference in AEW radar training simulator. The weather target display was realized by building weather controlling model and irregular form of weather target based on Bezier Curve and path developed was simulated by VC++. Interference display of AEW radar was realized by building model of various interference patterns and rejecting operation was simulated by building operating model. A lot of difficulties of PPI for AEW radar training simulator were settled: such as random distribution of weather target, irregular form of …

Research And Simulation Of Cross Flow Heat Exchanger, Chengyun Wu, Guangwen Wang, Geping Li, Xudong Xin

Journal of System Simulation

Abstract: Based on cell concept, the lumped parameter method was applied and the parameters in single heat exchanger cell were deduced. Thereafter 1, 4, 9,100 cells heat exchanger simulation model was set up and the simulation error and its influencing factors were analyzed. To simplify the algorithm and increase the calculation speed, as well as improve the accuracy of cross flow heat exchanger, the simplified heat exchanger model was proposed and reviewed. The research results show that the calculation of simplified heat exchanger is precise and the algorithm is simple. The model could be widely applied in cross flow heat …

A Novel Path Loss Forecast Model To Support Digital Twins For High Frequency Communications Networks, James Marvin Taylor Jr

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

The need for long-distance High Frequency (HF) communications in the 3-30 MHz frequency range seemed to diminish at the end of the 20th century with the advent of space-based communications and the spread of fiber optic-connected digital networks. Renewed interest in HF has emerged as an enabler for operations in austere locations and for its ability to serve as a redundant link when space-based and terrestrial communication channels fail. Communications system designers can create a “digital twin” system to explore the operational advantages and constraints of the new capability. Existing wireless channel models can adequately simulate communication channel conditions with …

Memcapacitor Model Based On Memristor, Zhaohui Gan, Yuxin Wu, Jiang Min, Shiying Zhang

Journal of System Simulation

Abstract: After physical model discovery of memristor in HP lab, the researchers put forward the concept of memcapacitor according to circuit theory. However, the physical object of the memcapacitor has not been found so far. In order to research the memcapacitor, researchers often use other components and circuits to simulate a memcapacitor. After analyzing the existing model of memcapacitor, a new nonlinear transformation method is proposed to transform a memristor into a memcapacitor, by which a nonlinear model of memcapacitor based on the memristor is constructed. The Pspice simulation experiments showed that the model successfully simulated the basic characteristics of …

Research On Simulation Platform For Equipment System Analysis, Yuping Li, Shaojie Mao, Zhenqi Ju, Zhou Fang, Guoqiang Yan

Journal of System Simulation

Abstract: With the development of equipment construction from platform-centric to network-centric, simulation analysis of equipment system is an important means and tool to support the transformation and development of equipment construction under the condition of multi-task joint operation. Starting from the requirement of system simulation analysis, a cloud-based equipment system simulation architecture is proposed to realize flexible and configurable simulation environment according to task requirements; and a high-performance simulation framework is conducted, which provides strong support for different application modes, such as parallel hyper-real-time and distributed simulation deduction. The unified description, organization and management method of model and data resources …

Survey Of Vision-Based Augmented Reality 3d Registration Technology, Shouming Hou, Han Ji, Yudong Zhang, Ziqiu Zhu

Journal of System Simulation

Abstract: Three-dimensional registration technology is one of the core technologies for augmented reality system implementation. In recent years, with the maturity of augmented reality hardware technology and the expansion of application fields, vision-based three-dimensional registration technology has received more attention and development. This paper introduces the basic principles and classification methods of 3D registration technology, focuses on the analysis of the principles and research status of three kinds of visual three-dimensional registration technology based on artificial identification, natural feature points and model.Furthermore, the defects and treatment methods of three visual registration technologies are discussed. The development prospect of visual 3D …

Survey On Modeling And Simulation Of Internet Public Opinion In China, Mingxin Zhang

Journal of System Simulation

Abstract: Modeling and Simulation of Internet public opinion can analyze the causes of public opinion and its transmission path, track and predict the trend of public opinion, so as to improve the ability of public opinion guidance for its control departments. This paper reviews and analyses the existing research on Modeling and simulation of Internet public opinion. From the point of view of research directions, the current research covers many directions, mainly including the evolution mechanism of Internet public opinion and the effectiveness of guidance mechanism. From the point of view of research methods, domestic research on Internet public opinion …

Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman

Chemistry Faculty Publications

The use of small unmanned aerial systems (sUAS) for meteorological measurements has expanded significantly in recent years. SUAS are efficient platforms for collecting data with high resolution in both space and time, providing opportunities for enhanced atmospheric sampling. Furthermore, advances in mesoscale weather research and forecasting (WRF) modeling and graphical processing unit (GPU) computing have enabled high resolution weather modeling. In this manuscript, a balloon-launched unmanned glider, complete with a suite of sensors to measure atmospheric temperature, pressure, and relative humidity, is deployed for validation of real-time weather models. This work demonstrates the usefulness of sUAS for validating and improving …

Generating Spectra Using Pca-Based Spectral Mixture Models, Joseph S. Makarewicz, Heather D. Makarewicz

Scholar Week 2016 - present

PCA-based spectra mixture models have been created for several laboratory mixture data sets. This presentation provides examples of spectra that were generated using PCA-based spectra mixture models.

Fractional-Order Memristor Model With Nonlinear Drift Function, Zhaohui Gan, Shiying Zhang, Yuxin Wu

Journal of System Simulation

Abstract: A memristor is a nonlinear resistor with memory. It is regarded as the fourth basic circuit elements. The fractional order model of memristor is an extension of integer order model for memristor. Some researchers have confirmed the existence of fractional order model for memristor, and the response characteristic of the fractional order model excited by different types of signals is analyzed. Based on the analysis of some existing integer order and fractional order models for memristor, a novel fractional order memristor model with nonlinear drift function is proposed, and the response characteristics of fractional order model for memristor with …

Method Research On Collaborative Simulation Of Multi-Resolution Models, Gaofeng Zhang, Yujie Ji

Journal of System Simulation

Abstract: The collaborative simulation of multi-resolution models is an effective method to meet the requirement of “wide-area confrontation and local high imitation” in combat simulation. The generalized supporting platform for multi-resolution models collaborative simulation is constructed, and the collaborative simulation mechanism with mirror entity and control right dynamic migration as core technology is proposed, which can effectively solve the problem of interconnection and homomorphic mapping between multi-resolution models, as well as collaborative operation consistency issues. Under the support of this technique, the joint operation among different resolution models in a tactical deduction simulation system is stable, efficient and consistent. This …

Mining And Validation Of Attacking Behavior In The Robocup 2d Simulation, Chen Bing, Zhang Heng, Zekai Cheng, Dong Peng, Lin Chao

Journal of System Simulation

Abstract: Robocup is an international academic competition which focuses on artificial intelligence and robotics. The 2D simulation is one of the earliest and most influential projects in Robocup. Attacking is the core behaviour of the simulated football game, as well as the attack recognition is considered as an important part in team-confrontations. This paper selects some active and contribution index of attacking, extracts lots of attacking behaviour data of the key agents, proposes two kinds of attacking patterns of 2D simulation, as ‘separate attack’ and ‘cooperative attack’, according to the human-player actions. The following simulation tests give the accuracy of …

Modeling And Simulation Of Difg Unit With Stator Inter-Turn Fault, Boqiang Xu, Liling Sun, Wenjuan Du

Journal of System Simulation

Abstract: The mathematical model of doubly fed induction generator (DFIG) with stator inter-turn fault, which presents itself as standard form state space equation, is deduced and established, for the first time. The corresponding simulation model, i.e. Matlab S-function block is developed and embedded in a Matlab built-in routine simulating DFIG unit comprising wind turbine, converter, related mechanical/electrical control and DFIG. The simulation model of DFIG unit with stator inter-turn fault is established, which is a beneficial extension of Matlab simulation. The stability of DFIG unit under the healthy and faulty conditions is analyzed by using simulation. The results show …

Fuel Flow Reduction Impact Analysis Of Drag Reducing Film Applied To Aircraft Wings, Damon Resnick, Chris Donlan, Nimish Sakalle, Cody Pinkerman

SMU Data Science Review

In this paper, we present an analysis of flight data in order to determine whether the application of the Edge Aerodynamix Conformal Vortex Generator (CVG), applied to the wings of aircraft, reduces fuel flow during cruising conditions of flight. The CVG is a special treatment and film applied to the wings of an aircraft to protect the wings and reduce the non-laminar flow of air around the wings during flight. It is thought that by reducing the non-laminar flow or vortices around and directly behind the wings that an aircraft will move more smoothly through the air and provide a …

Uav-Based Geotechnical Modeling And Mapping Of An Inaccessible Underground Site, Elizabeth Anne Russell

Graduate Theses & Non-Theses

Digital photogrammetry is becoming a more common method used for mapping geological and structural rock mass features in underground mining. The issue of capturing geological and structural data in inaccessible, unsupported areas of mines remains even when utilizing terrestrial photogrammetric methods; thus, geotechnical models of mines are left with incomplete datasets. Large unsupported underground voids, like stopes, have the potential to cause major failures, but by filling in the geotechnical data gaps in inaccessible areas, potential failures can be predicted through kinematic analysis of the area’s mapped discontinuities. Implementation of Unmanned Aerial Vehicles (UAVs) in underground mines and recent advances …

A Self-Organized Learning Model For Anomalies Detection: Application To Elderly People, Nicolas R. Verstaevel, Jean-Pierre George, Carole Bernon, Marie-Pierre Gleizes

SMART Infrastructure Facility - Papers

In a context of a rapidly growing population of elderly people, this paper introduces a novel method for behavioural anomaly detection relying on a self-organized learning process. This method first models the Circadian Activity Rhythm of a set of sensors and compares it to a nominal profile to determine variations in patients' activities. The anomalies are detected by a multi-agent system as a linear relation of those variations, weighted by influence parameters. The problem of adaptation to a particular patient then becomes the problem of learning the adequate influence parameters. Those influence parameters are self-adjusted, using feedback provided at any …

A Dynamic Behavioural Traffic Assignment Model With Strategic Agents, Johan Barthelemy, Timoteo Carletti

SMART Infrastructure Facility - Papers

Foresee traffic conditions and demand is a major issue nowadays that is very often approached using simulation tools. The aim of this work is to propose an innovative strategy to tackle such problem, relying on the presentation and analysis of a behavioural dynamic traffic assignment. The proposal relies on the assumption that travellers take routing policies rather than paths, leading us to introduce the possibility for each simulated agent to apply, in real time, a strategy allowing him to possibly re-route his path depending on the perceived local traffic conditions, jam and/or time already spent in his journey. The re-routing …

Railnet: A Simulation Model For Operational Planning Of Rail Freight, Guillaume Michal, Nam N. Huynh, Nagesh Shukla, Albert Munoz, Johan Barthelemy

SMART Infrastructure Facility - Papers

In many rail networks, infrastructure constraints force the shared usage of lines between passenger and freight movements. Scheduling additional freight movements around existing passenger services and peak traffic based curfews presents significant challenges to commodity industries eager to increase export volumes. This paper addresses the problem of inserting additional freight movements in a constrained railway network. To this end, a railway operations planning model was developed to simulate and insert feasible rail movements in a non-periodic timetable. The simulation modelling platform developed in this paper is called RailNet, which simulates the existing railway network constraints and is capable of adding …

Individual-Level Simulation Model For Cost Benefit Analysis In Healthcare, Nagesh Shukla, Vu Lam Cao, Van Hoang Phuong, Marian D. Shanahan, Alison Ritter, Pascal Perez

SMART Infrastructure Facility - Papers

Illicit drug use creates significant burden at societal, family and personal levels. Every year substantial resources are allocated for treatment and the consequences of illicit drug use in Australia and around the world. Heroin is one of the major forms of illicit drugs. Several independent heroin treatment strategies or interventions exist and state-of-the art research demonstrates their efficacy and relative costeffectiveness. However, assessing total potential gains and burden from providing all treatment interventions or varying the mix of heroin treatments has never been attempted. This paper proposed an individual-level simulation model (ISM) which addresses net social benefit over a lifetime …

Case Study: A Model Based Systems Engineering (Mbse) Framework For Characterising Transportation Systems Over The Full Life Cycle, William R. Scott, Richard Fullalove, Gary Arabian, Allan P. Campbell

SMART Infrastructure Facility - Papers

Development of transport infrastructure has significant challenges including acquisition lag, phased evolution, multiple disparate stakeholders and environment-specific issues. The Asset Standards Authority (ASA) at TfNSW is introducing MBSE to address these challenges. Instrumental to the introduction is the development of a framework that structures the available data and provides guidance and traceability between the data sets. This framework combines the enterprise-level drivers with the lower level drivers such as standards to outline a generic conceptual design for a transport system. This conceptual design is then used to guide future system development. The outcome is future project information based on greater, …

Interest Detection In Image, Video And Multiple Videos: Model And Applications, Yuewei Lin

Theses and Dissertations

Interest detection is detecting an object, event, or process that draws attention. In this dissertation, we focus on interest detection in images, video and multiple videos. Interest detection in an image or a video is closely related to visual attention. However, the interest detection in multiple videos needs to consider all the videos as a whole rather than considering the attention in each single video independently.

Visual attention is an important mechanism of human vision. The computational model of visual attention has recently attracted a lot of interest in the computer vision community mainly because it helps find the objects …

Applying A Novel Combination Of Techniques To Develop A Predictive Model For Diabetes Complications, Mohsen Sangi, Khin Than Win, Farid Shirvani, Mohammad-Reza Namazi-Rad, Nagesh Shukla

Nagesh Shukla

No abstract provided.

A Stochastic And Flexible Activity Based Model For Large Population Application To Belgium, Johan Barthelemy, Philippe L. Toint

SMART Infrastructure Facility - Papers

The VirtualBelgium project aims at developing an understanding of the evolution of the Belgian population using agent-based simulations and considering various aspects of this evolution such as demographics, residential choices, activity patterns, mobility, etc. This simulation is based on a validated synthetic population consisting of approximately 10,000,000 individuals and 4,350,000 households located in the 589 municipalities of Belgium. The work presented in this paper focuses only on the mobility behaviour of such large populations and this is simulated using an activity-based approach in which the travel demand is derived from the activities performed by the individuals. The proposed model is …