Engineering Commons^™

Quasi 1d Modelling Of A Scramjet Engine Cycle Using Heiser-Pratt Approach, Asmaa Chakir

Theses and Dissertations

Scramjet engines are key for sustained hypersonic flights. Analytic models play a critical role in the preliminary design of a scramjet engine configuration. The objective of this research is to develop and validate a quasi-1D model for the scramjet engine encompassing inlet, isolator and combustor, to evaluate the impact of flight conditions and design parameters on the engine functionality. The model is developed assuming isentropic flow in the inlet with a single turn; modified Fanno-flow equations in the isolator that account for the area change of the core flow; and the combustor is modeled using Heiser-Pratt equations accounting for the …

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 …

A Two-Layer Continuous-Capillary Oxygen Transport Model: Development And Application To Blood Flow Regulation In Resting Skeletal Muscle., Keith C. Afas

Electronic Thesis and Dissertation Repository

In skeletal muscle (SM), the microcirculation distributes blood flow to capillary networks to meet local oxygen (O₂) demand. Experiments using intra-vital video microscopy (IVVM) have quantified blood flow and O₂ supply in capillary networks, and using an O₂ exchange chamber have measured local changes in blood flow believed due to O₂-dependent regulation. However, IVVM is unable to simultaneously measure capillary O₂ supply and SM O₂ content, implying the need for theoretical models to understand how flow regulation and SM oxygenation interact. In this thesis, a novel blood-tissue O₂ transport model using …

Effects Of Imu Sensor Location And Number On The Validity Of Vertical Acceleration Time-Series Data In Countermovement Jumping, Dianne Althouse

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Many devices are available for measuring the height of a CMJ. An inertial measurement unit (IMU) measures linear acceleration, orientation, and angular velocity. As an alternative to using IMU estimates of flight time, CMJ height could be estimated by integrating the IMU time-series signal for vertical acceleration to derive CMJ take-off velocity in order to track whole-body center of mass (WBCoM) movement, yet this approach would require valid IMU acceleration data. Thus, the purpose of this study was to quantify the effects of IMU sensor location and number on the validity of vertical acceleration estimation in CMJ. Thirty young adults …

Development And Testing Of A 1:70 Scale Model Wind Turbine Of The Iea Reference 15 Mw Floating Offshore System, Amber Parker

Electronic Theses and Dissertations

This thesis presents the development of a 1/70th scale performance-matched wind turbine intended for wind and wave basin model testing of commercially viable floating wind turbine structures based off of the International Energy Agency (IEA) Wind 15 MW design. The focus of this demonstration is to test active blade pitch response controls and to provide an experimental dataset for use by modelers and industry for future turbine improvements. Future research is planned to test the turbine in conjunction with an actively damping hull to test the interactions between the two control systems.

Outlined in this thesis are the methods of …

Live Access Control Policy Error Detection Through Hardware, Bryce Mendenhall

Graduate Theses and Dissertations

Access Control (AC) is a widely used security measure designed to protect resources and infrastructure in an information system. The integrity of the AC policy is crucial to the protection of the system. Errors within an AC policy may cause many vulnerabilities such as information leaks, information loss, and malicious activities. Thus, such errors must be detected and promptly fixed. However, current AC error detection models do not allow for real-time error detection, nor do they provide the source of errors. This thesis presents a live error detection model called LogicDetect which utilizes emulated Boolean digital logic circuits to provide …

Integrating Fire Responses To Combat Wildfires, Jonathan Leonard Badal

Electrical Engineering

Each year wildfires cause significant loss of property, worsen people’s health, and destroy multiple ecosystems. On average, a wildfire season costs anywhere from 7.6-62.8 billion dollars due to fire containment, repair, and restoration [1]. It can take decades to recover from the crippling loss of land and take even longer to fully restore it. However, with the implementation of a robust early detection system, these losses can be significantly reduced. The current process for identifying wildfires involves visual identification, phone call alerts, and media tools primarily driven by park rangers and public reporting. Unfortunately, this system is not preventative and …

System Performance Model And Control System For A Small-Scale Horizontal Axis Wind Turbine, Niko Banks

Master's Theses

Predicting the performance of wind turbines is a key part of the turbine design process and operation, as predictive models play a large role in determining potential power output and efficiency at different operating conditions to help maximize production. On small-scale wind turbines performance models become more complex, as the rotor aerodynamic performance depends not only on the tip speed ratio, but also on the flow Reynolds number. An accurate predictive model that includes this behavior on small-scale wind turbines can be used to find the optimal operating conditions for power output, and is also a critical component of the …

Law School News: National Housing Advocate Named To Lead Rwu's New Real Estate Initiatives 02/08/2022, Roger Williams University School Of Law

Life of the Law School (1993- )

No abstract provided.

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 …

Development Of Methane Emissions Model To Assess Fuel Recovery Potential At Gas Well Sites Using On Site Compression, Nicholas G. Lindenfeldar

Graduate Theses, Dissertations, and Problem Reports

The US natural gas production and consumption has increased 85.5% since 2005 primarily due to the unconventional production methods of horizontal drilling and hydraulic fracturing. Natural gas used as a fuel has a lower greenhouse gas (GHG) footprint than coal and petroleum due to lower Carbon Dioxide (CO₂) emissions when combusted. However, the “greener” benefit to natural gas may be consumed by leaks in production and transmission systems. Methane (CH₄), the primary hydrocarbon in natural gas, has an estimated Global Warming Potential (GWP) of 28-36 over 100 years, meaning it can absorb 28-36 more energy than …

Validation Of The Ambassador Questionnaire For Undergraduate Students Conducting Engineering Outreach, Melissa G. Kuhn, Shanan Chappell Moots, Joanna K. Garner

Center for Educational Partnerships Publications

Although K-12 engineering outreach commonly involves college students, the young professionals who act as ambassadors for their field are less likely to be studied than the students they serve. Yet, outreach activities may offer opportunities for undergraduate students to develop aspects of their professional selves. As there is currently no comprehensive measure that allows researchers, program evaluators, and outreach advisors to examine ambassadors' professional development and growth, this study sought to develop and validate an Ambassador Questionnaire (AQ). The multi-step process included the selection and adaptation of items from extant measures of engineering students' motivation, beliefs, professional skills, and perceptions …

A Framework For Designing Blockchain Systems In A Smart City Setting, Mohammad Alhefdi

All ETDs from UAB

As main characteristics of successful smart cities, the high demand for increased data security and accessibility and citizen engagement mean the role of blockchain technology has begun to increase. Nonetheless, blockchain technology also faces several challenges, which have slowed its adoption. In response, this dissertation introduces a framework for designing blockchain systems in a smart city setting and considers the smart city and blockchain challenges. Researchers have proposed several smart city models that study and analyze the complexity of smart cities to improve city security, functionality, services, and smartness. The proposed information-theoretical modeling approach to generate an innovated blockchain model …

A Framework For Enterprise Systems Based On Process Improvement, Abdulrahman Alharthi

All ETDs from UAB

We introduce a framework for enterprise systems based on process-centered analysis. Because technology has drastically altered many aspects of our lives, such as work, leisure, travel, government, and company interactions worldwide, companies must strategically consider the Internet of Things in order to thrive in the new economy. Tanik and Jololian offered early work in this area, and included an analysis of the T-Strategy introduced by R.T. Yeh et al. in their book “Zero-time.” Our approach builds on this decade-old work, and involves the introduction of information flow analysis to process improvement [1]. We have identified two key points: centralization and …