Engineering Commons^™

Analysis Of Pilot-Induced-Oscillation And Pilot Vehicle System Stability Using Uas Flight Experiments, Tanmay K. Mandal, Yu Gu

Faculty & Staff Scholarship

This paper reports the results of a Pilot-Induced Oscillation (PIO) and human pilot control characterization study performed using flight data collected with a Remotely Controlled (R/C) unmanned research aircraft. The study was carried out on the longitudinal axis of the aircraft. Several existing Category 1 and Category 2 PIO criteria developed for manned aircraft are first surveyed and their effectiveness for predicting the PIO susceptibility for the R/C unmanned aircraft is evaluated using several flight experiments. It was found that the Bandwidth/Pitch rate overshoot and open loop onset point (OLOP) criteria prediction results matched flight test observations. However, other criteria …

Development Of Chemical Process Design And Control For Sustainability, Shuyun Li, Gaurav Mirlekar, Gerardo J. Ruiz-Mercado, Fernando V. Lima

Faculty & Staff Scholarship

This contribution describes a novel process systems engineering framework that couples advanced control with sustainability evaluation for the optimization of process operations to minimize environmental impacts associated with products, materials and energy. The implemented control strategy combines a biologically-inspired method with optimal control concepts for finding more sustainable operating trajectories. The sustainability assessment of process operating points is carried out by using the U.S. EPA’s Gauging Reaction Effectiveness for the ENvironmental Sustainability of Chemistries with a multi-Objective Process Evaluator (GREENSCOPE) tool that provides scores for the selected indicators in the economic, material efficiency, environmental and energy areas. The indicator scores …

Coal Quality Management Model For Dome Storage (Ds-Cqmm), M. A. Badani-Prado, V. Kecojevic, D. Bogunovic

Faculty & Staff Scholarship

Coal quality (ash, sulphur, moisture, and heating value) is one of the fundamental concerns for both coal mines and power plants. In order to deliver uniform coal quality to the power plant, there is a need for realtime monitoring of coal quality from the mine to the coal stockpiles. The specific problem represents the process of stacking the coal inside an enclosed facility such as a dome. The objective of this research was to develop a custom-made and integrated coal quality management model for dome storage (DS-CQMM). The DS-CQMM merges existing technology in surface mines, such as coal analysers, together …

Latest Advances In The Generation Of Single Photons In Silicon Carbide, Albert Boretti, Lorenzo Rosa

Faculty & Staff Scholarship

: The major barrier for optical quantum information technologies is the absence of reliable single photons sources providing non-classical light states on demand which can be easily and reliably integrated with standard processing protocols for quantum device fabrication. New methods of generation at room temperature of single photons are therefore needed. Heralded single photon sources are presently being sought based on different methods built on different materials. Silicon Carbide (SiC) has the potentials to serve as the preferred material for quantum applications. Here, we review the latest advances in single photon generation at room temperatures based on SiC.

Modeling And Optimization Of High-Performance Polymer Membrane Reactor Systems For Water–Gas Shift Reaction Applications, Andrew J. Radcliffe, Rajinder P. Singh, Kathryn A. Berchtold, Fernando V. Lima

Faculty & Staff Scholarship

In production of electricity from coal, integrated gasification combined cycle plants typically operate with conventional packed bed reactors for the water-gas shift reaction, and a Selexol process for carbon dioxide removal. Implementation of membrane reactors in place of these two process units provides advantages such as increased carbon monoxide conversion, facilitated CO2 removal/sequestration and process intensification. Proposed H2-selective membranes for these reactors are typically of palladium alloy or ceramic due to their outstanding gas separation properties; however, on an industrial scale, the cost of such materials may become exorbitant. High-performance polymeric membranes, such as polybenzimidazoles (PBIs), present themselves as low-cost …

Glidar: An Opengl-Based, Real-Time, And Open Source 3d Sensor Simulator For Testing Computer Vision Algorithms, John O. Woods, John A. Christian

Faculty & Staff Scholarship

3D sensors such as LIDARs, stereo cameras, time-of-flight cameras, and the Microsoft Kinect are increasingly found in a wide range of applications, including gaming, personal robotics, and space exploration. In some cases, pattern recognition algorithms for processing depth images can be tested using actual sensors observing real-world objects. In many situations, however, it is common to test new algorithms using computer-generated synthetic images, as such simulations tend to be faster, more flexible, and less expensive than hardware tests. Computer generation of images is especially useful for Monte Carlo-type analyses or for situations where obtaining real sensor data for preliminary testing …

Analysis Of Camera Arrays Applicable To The Internet Of Things, Jiachen Yang, Ru Xu, Zhihan Lv, Houbing Song

Faculty & Staff Scholarship

The Internet of Things is built based on various sensors and networks. Sensors for stereo capture are essential for acquiring information and have been applied in different fields. In this paper, we focus on the camera modeling and analysis, which is very important for stereo display and helps with viewing. We model two kinds of cameras, a parallel and a converged one, and analyze the difference between them in vertical and horizontal parallax. Even though different kinds of camera arrays are used in various applications and analyzed in the research work, there are few discussions on the comparison of them. …

Genotoxic Effects Of Synthetic Amorphous Silica Nanoparticles In The Mouse Lymphoma Assay, Esref Demir, Vincent Castranova

Faculty & Staff Scholarship

Synthetic amorphous silica nanoparticles (SAS NPs) have been used in various industries, such as plas-tics, glass, paints, electronics, synthetic rubber, in pharmaceutical drug tablets, and a as food additive in many processed foods. There are few studies in the literature on NPs using gene mutation approaches in mammalian cells, which represents an important gap for genotoxic risk estimations. To fill this gap, themouse lymphoma L5178Y/Tk+/−assay (MLA) was used to evaluate the mutagenic effect for five different concentrations (from 0.01 to 150 g/mL) of two different sizes of SAS NPs (7.172 and 7.652 nm) and a fine collodial form of silicon …

On Micro-Buckling Of Unidirectional Fiber-Reinforced Composites By Means Of Computational Micromechanics, Nestor D. Barulich, Luis A. Godoy, Ever J. Barbero

Faculty & Staff Scholarship

Micro-buckling of unidirectional fiber-reinforced composites is investigated in this paper by means of an explicit representation of a geometrically imperfect fiber within the context of kinematical and material non-linear behavior. Two types of fiber imperfections are considered: a helicoidal shape, identified as 3D imperfection; and a sinusoidal plane shape (2D imperfection). Both imperfection models are characterized by a maximum misalignment angle of the fiber with respect to the ideal or perfect configuration, as is usually considered in this field. A total of 816 cases were computed in terms of imperfection type (either 2D or 3D), fiber volume fraction, fiber arrangement …

Autonomous Close Formation Flight Control With Fixed Wing And Quadrotor Test Beds, Caleb Rice, Yu Gu, Haiyang Chao, Trenton Larrabee, Srikanth Gururajan, Marcello Napolitano, Tanmay Mandal, Matthew Rhudy

Faculty & Staff Scholarship

Autonomous formation flight is a key approach for reducing energy cost and managing traffic in future high density airspace. The use of Unmanned Aerial Vehicles (UAVs) has allowed low-budget and low-risk validation of autonomous formation flight concepts. This paper discusses the implementation and flight testing of nonlinear dynamic inversion (NLDI) controllers for close formation flight (CFF) using two distinct UAV platforms: a set of fixed wing aircraft named “Phastball” and a set of quadrotors named “NEO.” Experimental results show that autonomous CFF with approximately 5-wingspan separation is achievable with a pair of low-cost unmanned Phastball research aircraft. Simulations of the …

Compensation For Cross-Coupled Dynamics Of Dual Twisted-String Actuation Systems, Lei Jiang, Yuejuan Li, Marvin H. Cheng

Faculty & Staff Scholarship

Twisted-string actuation devices have been adopted in various robotic systems due to their advantages of compact size and simple structure. To precisely control the displacement of such devices, a dual-direction actuating mechanism, which provides both extension and contraction of two strings simultaneously, must be implemented. Due to the physical properties of twisted string, the actuator has problems of nonlinear length variation and cross-coupled relationships between two strings. In this study, two controllers (PID-FC and LQR-FC) were synthesized with the consideration of cross-coupling dynamics between the two axes. The experimental results demonstrate the performance of both tracking and synchronization responses of …

A Novel Energy-Efficient K-Coverage Algorithm Based On Probability Driven Mechanism Of Wireless Sensor Networks, Chuanfeng Li, Zeyu Sun, Huihui Wang, Houbing Song

Faculty & Staff Scholarship

In the process of fulfilling ��-coverage over target nodes, a large quantity of redundant data may be produced, which will cause network congestion, reduce communication efficiency, impair coverage quality, and exhaust network energy quickly. To solve this problem, the paper proposes an Energy-Efficient k-Coverage Algorithm (EEKCA), which attempts to construct a network coverage model by utilizing the relative positions of nodes. Through analyzing the model, the coverage expectations for nodes in the monitored area and the minimum number of nodes required for full coverage are computed. As for power consumption, the paper presents an energy shifting function between working nodes …

A Fault-Tolerant Multiple Sensor Fusion Approach Applied To Uav Attitude Estimation, Yu Gu, Jason N. Gross, Matthew B. Rhudy, Kyle Lassak

Faculty & Staff Scholarship

A novel sensor fusion design framework is presented with the objective of improving the overall multisensor measurement system performance and achieving graceful degradation following individual sensor failures. The Unscented Information Filter (UIF) is used to provide a useful tool for combining information from multiple sources. A two-step off-line and on-line calibration procedure refines sensor error models and improves the measurement performance. A Fault Detection and Identification (FDI) scheme crosschecks sensor measurements and simultaneously monitors sensor biases. Low-quality or faulty sensor readings are then rejected from the final sensor fusion process. The attitude estimation problem is used as a case study …

An Energy-Efficient Skyline Query For Massively Multidimensional Sensing Data, Yan Wang, Wei Wei, Qingxu Deng, Wei Liu, Houbing Song

Faculty & Staff Scholarship

Cyber physical systems (CPS) sense the environment based on wireless sensor networks. The sensing data of such systems present the characteristics of massiveness and multi-dimensionality. As one of the major monitoring methods used in in safe production monitoring and disaster early-warning applications, skyline query algorithms are extensively adopted for multiple-objective decision analysis of these sensing data. With the expansion of network sizes, the amount of sensing data increases sharply. Then, how to improve the query efficiency of skyline query algorithms and reduce the transmission energy consumption become pressing and difficult to accomplish issues. Therefore, this paper proposes a new energy-efficient …

Best-Mac: Bitmap-Assisted Efficient And Scalable Tdma-Based Wsn Mac Protocol For Smart Cities, Ahmad Naseem Alvi, Safdar Hussain Bouk, Syed Hassan Ahmed, Muhammad Azfar Yaqub, Mahasweta Sarkar, Houbing Song

Faculty & Staff Scholarship

Smart cities have been envisioned during the last decade. Moreover, various projects have been initiated to bring this concept into reality. Smart city is basically an emergence of the existing and new Information and Communications Technologies (ICT) to make our living standard more safe and digitized. Wireless communications, such as sensors, actuators, intelligent transportation systems, and smart grids, have played a vital role in the dissemination of information under the given circumstances. Similarly, it is hard to declare any city as a smart city without taking benefits from wireless sensor networks (WSNs). However, with new requirements and delay sensitive applications, …

Anchor-Assisted And Vote-Based Trustworthiness Assurance In Smart City Crowdsensing, Maryam Pouryazdan, Burak Kantarci, Tolga Soyata, Houbing Song

Faculty & Staff Scholarship

Smart city sensing calls for crowdsensing via mobile devices that are equipped with various built-in sensors. As incentivizing users to participate in distributed sensing is still an open research issue, the trustworthiness of crowdsensed data is expected to be a grand challenge if this cloud-inspired recruitment of sensing services is to be adopted. Recent research proposes reputation-based user recruitment models for crowdsensing; however, there is no standard way of identifying adversaries in smart city crowdsensing. This paper adopts previously proposed vote-based approaches, and presents a thorough performance study of vote-based trustworthiness with trusted entities that are basically a subset of …

Internet Of Things And Big Data Analytics For Smart And Connected Communities, Yunchuan Sun, Houbing Song, Antonio J. Jara, Rongfang Bie

Faculty & Staff Scholarship

This paper promotes the concept of smart and connected communities SCC, which is evolving from the concept of smart cities. SCC are envisioned to address synergistically the needs of remembering the past (preservation and revitalization), the needs of living in the present (livability), and the needs of planning for the future (attainability). Therefore, the vision of SCC is to improve livability, preservation, revitalization, and attainability of a community. The goal of building SCC for a community is to live in the present, plan for the future, and remember the past. We argue that Internet of Things (IoT) has the potential …

Changing States Of Multistage Process Chains, Thorsten Wuest, Christopher Irgens, Klaus-Dieter Thoben

Faculty & Staff Scholarship

Generally, a process describes a change of state of some kind (state transformation). This state change occurs from an initial state to a concluding state. Here, the authors take a step back and take a holistic look at generic processes and process sequences from a state perspective. The novel perspective this concept introduces is that the processes and their parameters are not the priority; they are rather included in the analysis by implication. A supervised machine learning based feature ranking method is used to identify and rank relevant state characteristics and thereby the processes’ inter- and intrarelationships. This is elaborated …

Carbon Dioxide Fluxes Reflect Plant Zonation And Belowground Biomass In A Coastal Marsh, Serena Moseman-Valtierra, Omar I. Abdul-Aziz, Jianwu Tang, Khandker S. Ishtiaq, Kate Morkeski, Jordan Mora, Ryan K. Quinn, Rose M. Martin, Katharine Egan, Elizabeth Q. Brannon, Joanna Carey, Kevin D. Kroeger

Faculty & Staff Scholarship

Coastal wetlands are major global carbon sinks; however, they are heterogeneous and dynamic ecosystems. To characterize spatial and temporal variability in a New England salt marsh, greenhouse gas (GHG) fluxes were compared among major plant-defined zones during growing seasons. Carbon dioxide (CO2) and methane (CH4) fluxes were compared in two mensurative experiments during summer months (2012–2014) that included low marsh (Spartina alterniflora), high marsh (Distichlis spicata and Juncus gerardiidominated), invasive Phragmites australis zones, and unvegetated ponds. Day- and nighttime fluxes were also contrasted in the native marsh zones. N2O fluxes were measured in parallel with CO2 and CH4 fluxes, but …

Accelerated Hyperspectral Unmixing With Endmember Variability Via The Sum-Product Algorithm, Charan Puladas

Browse all Theses and Dissertations

The rich spectral information captured by hyperspectral sensors has given rise to a number of remote sensing applications, ranging from vegetative assessment and crop health monitoring, to military surveillance and combatant identification. However, due to limited spatial resolution, multiple ground materials generally contribute, i.e. mix, to form the spectrum recorded for a single pixel. The unmixing problem considers the inverse problem of determining the underlying material spectra, called endmembers, from sensor measurements. While classical unmixing approaches were deterministic in nature and did not attempt to identify in-scene materials, recent methods use labeled training data to generate statistical models of endmember …

Novel Cell Killing Mechanism Of Hydroxyurea In The Fission Yeast Schizosaccharomyces Pombe And Its Implications In Improving Antifungal Therapy, Amanpreet Singh

Browse all Theses and Dissertations

Hydroxyurea (HU, also known as hydroxycarbamide) is a well known ribonucleotide reductase (RNR) inhibitor that depletes cellular deoxyribonucleoside triphosphates (dNTPs, the building blocks of DNA). Depleted dNTP pools inside the proliferating cells stalls ongoing DNA replication forks, leading to the activation of the well-conserved DNA replication checkpoint (also known as intra-S phase checkpoint) pathway. One of the major functions of the checkpoint pathway is to protect ongoing forks from collapsing. Stalled forks, if not protected by the checkpoint pathway, lead to DNA damage and ultimately cell death. Thus it is believed that DNA damage resulting from collapsed forks is the …

Creativity In Design Teams: The Influence Of Personality Traits And Risk Attitudes On Creative Concept Selection, Christine Toh, Scarlett Miller

Interdisciplinary Informatics Faculty Publications

Concept selection is recognized as a crucial component of the design process that largely involves informal group discussions within design teams. However, little is known about what factors affect the selection or filtering of creative ideas during this process. This is problematic because in order for innovation to occur, individuals must first identify and select the creative concepts developed in the early stages of design. However, prior research has shown that individuals tend to select conventional alternatives during this process due to the inherent risk associated with creative concepts. Therefore, the current study was developed to understand how personality traits, …

Unmanned Aerial Vehicle For Vertically Profiling Ultrafine Particle Distribution, Ahmed Almutawa, Ola Saadeh, Mudaher Alkhawajah, Grant Carey

Capstone Design Expo Posters

Recent epidemiologic studies show that ultrafine particles (UFPs) may play a definitive role in development of pulmonary and cardiovascular diseases, as well as cancer related mortality. In order to support the growing interest in understanding the effects of UFPs on human health, Dr. Chen has developed a miniaturized electronic ultrafine particle sizing device, or mini-eUPS. This device utilizes many of the functions of equipment currently used in laboratory environments to test and measure UFP levels in aerosols, but has been miniaturized to maximize mobility and ease of use. The small size and weight of the device allow a unique ability …

Transparent Furnace For Observing Electrochemical Separation Of Used Nuclear Fuel, Hoor Almazmi, Abbie Dewitte, Kelli Mckenna, Svetlana Ruseva

Capstone Design Expo Posters

Electrochemical separation of used nuclear fuel (UNF) operating at 500°C is confined within a furnace, making it difficult for a visual observation. Thus, flow characteristic predictions from the furnace are often calculated through advanced computational modeling methods. Therefore, it is necessary to develop an innovative idea, combining mechanical and chemical skill sets to design and build a transparent furnace that provides a clear visualization that can later be coupled with an optical flow-visualization method, such as Laser Doppler Anemometry (LDA). Deliverables of the project include the complete design and illustration of the prototype operating up to 500°C. Challenges of the …

Electromechanical Robotic Platform For Patient Motion Management In Radiotherapy, Thomas Dwyer, Ross Cruikshank, Daniel Martinez, Melvin Rosario

Capstone Design Expo Posters

Head and neck cancer is often treated with radiation therapy. During this treatment, patient movement causes healthy cells to receive excessive radiological dose. We have designed an electromechanical robotic platform that enables compensation of patient movement during treatment. This project includes analysis of materials and motion of the system, design of the control system and model, and the functional prototype. The design of the robotic platform will be compatible with pre-existing head and mouth harnesses in order to keep a patient’s head steady while the patient’s headrest in motion. For radiotherapy, this system requires radio-compatible materials. Through the use of …

Continuously Expanding Mandrel, Cory Bleistein, Dylan Dawson, Anton Rabinky, Marshall Smith

Capstone Design Expo Posters

The purpose of this project was to develop a better, safer, more efficient system for Sealeze to manufacture spiral-wrapped strip brushes in a continuous fashion at a variable diameter. The end results produced a finalized drawing sheet for machining and production, numerous design variations within CAD drawings, and extensive mechanical evaluations and analyses proving the strength and capabilities of the proposed design. In production of these brushes, various different materials will be used for the core, backing, and filament, creating a need for a mandrel that will be strong enough to handle the most resiliant of materials while maintaining a …

Flow-Differential Pressure Test Rig, Stuart Jennings, David Keegan, Juan Ramonet, Nicholas Upton

Capstone Design Expo Posters

provider of filters for critical applications in various industries, Porvair Filtration Group often needs to validate the pressure drop across a given filter medium at various flow rates and to perform quality assurance prior to delivery. The Flow-Differential Pressure Test Apparatus will allow for a test cycle with significant savings in time and money for Porvair going forward.

The design uses high-purity deionized water as the test fluid and performs continual filtration to ensure consistent properties. Flow rates of 0-100 gallons per minute at pressures up to 100 psi gauge are achieved by controlling a pump with i) a variable-frequency …

People Counting In Open Spaces, Nick Reuter, Taylor Roberts, Chris Thomas

Capstone Design Expo Posters

The need addressed in this project is to accurately keep track of individuals in Richmond parks, and provide real-time actionable data for analysis and response. To do this, Satellite systems take pictures, perform object detection and send data to the Central Controller. Central Controller performs accuracy analysis and records end result. It also sends client commands to the satellite systems. Remote client gathers data from the central controller, and allows the user to change satellite system’s operation modes.

There were several constraints associated with the project 1) Supplied Power 2) Privacy protection 3) Number of satellite units (cost) 4) People …

Automatic Sorting Machine Using A Programmable Logic Controller, Tim Parker, Justin Webber, Josh Kirkham

Capstone Design Expo Posters

This project is designed to demonstrate the uses of programmable logic controllers (PLC’s). The end result of this project will be used to generate interest in VCU’s Industrial Controls classes with prospective students as well as employers. The project involves building a working demonstration showing how PLC’s are used to control manufacturing systems. This system will be mobile and able to be used in different locations including the PLC lab, where students in the Industrial Controls class can also use it to test their knowledge of PLC programming. The system consists of a conveyor belt and sensors that sorts different …

Rfid Based Navigation, Mengyu Bai, Andrew Sainz, So Kim

Capstone Design Expo Posters

The RFID (Radio Frequency Identification) based Navigation System is built and designed to allow both commercial and recreational drivers to know and monitor traffic patterns while on the road. By using the RFID based Navigation System, drivers will receive real time data to aid navigation which is a major benefit especially in an emergency situation. Further studies of the RFID technology will potentially open doors to the development of autonomous vehicles. The RFID based Navigation application is available for Android devices, and it presents drivers with real time, current data to aid navigation across a terrain in the shortest possible …