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2021

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Articles 5101 - 5130 of 9983

Full-Text Articles in Engineering

Exploration Of The Sludge Biodiesel Pathway, Zachary Christman May 2021

Exploration Of The Sludge Biodiesel Pathway, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Wastewater sludge is an overlooked source of fat, oil, and grease (FOG) that could be converted into biodiesel. The United States produces about 8 million tons of sludge per year. The disposal cost for this amount of sludge is about 2 billion US dollars. The widespread availability and low cost of sludge compared to other biodiesel raw materials make it an economical choice for a renewable fuel. Using sludge as a raw material can produce 25 to 30 mg per gram of fatty acid methyl ester (FAME); the main component of biodiesel. Sludge biodiesel has the potential of transforming a …


The Correlation Between Poverty, Water Quality, Community Health, And Education In Guatemala And Tanzania, Jessica R. Besnier May 2021

The Correlation Between Poverty, Water Quality, Community Health, And Education In Guatemala And Tanzania, Jessica R. Besnier

Senior Honors Projects, 2020-current

This paper explores the relationship between poverty, water quality, community health, and education in Tanzania and Guatemala. These metrics will allow for a thorough analysis of the relationships between the countries and will determine their impact on the other aspects in these two countries. While Guatemala and Tanzania are very different countries, they share many things in common such as inequalities among different groups, having many different groups of indigenous people, having most people living in rural areas, and are located on a coast. Also, they share similarities regarding poverty, water quality, community health, and education. By looking into these …


The Effect Of Nanostructures In Aluminum Alloys Processed Using Additive Manufacturing On Microstructural Evolution And Mechanical Performance Behavior, Rachel Boillat, Sriram Praneeth Isanaka, Frank W. Liou May 2021

The Effect Of Nanostructures In Aluminum Alloys Processed Using Additive Manufacturing On Microstructural Evolution And Mechanical Performance Behavior, Rachel Boillat, Sriram Praneeth Isanaka, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper reviews the status of nanoparticle technology as it relates to the additive manufacturing (AM) of aluminum-based alloys. A broad overview of common AM processes is given. Additive manufacturing is a promising field for the advancement of manufacturing due to its ability to yield near-net-shaped components that require minimal post-processing prior to end-use. AM also allows for the fabrication of prototypes as well as economical small batch production. Aluminum alloys processed via AM would be very beneficial to the manufacturing industry due to their high strength to weight ratio; however, many of the conventional alloy compositions have been shown …


Physical Layer Security Of The Internet Of Things: Modeling And Analysis, Ali Alsadi May 2021

Physical Layer Security Of The Internet Of Things: Modeling And Analysis, Ali Alsadi

Theses and Dissertations

Motivated by the fifth generation of mobile networks, the Internet of Things (IoT) has emerged as one of the most promising and interesting technologies that are currently evolving IoT, which is expected to be deployed on a large-scale beyond 2020. However, this technology's main drawback is the security issue due to the variety of network access technologies and the wireless medium's nature. Thus, in the last decade, considerable efforts were expended to address this issue. However, much of the work has focused on the data link and upper layers, and much less attention has been given to the physical layer …


Machine Learning Applied To Colloidal Properties Of Perfluorocarbon Nanoemulsions For Imaging In Ards/Ali, Marco Hosfeld May 2021

Machine Learning Applied To Colloidal Properties Of Perfluorocarbon Nanoemulsions For Imaging In Ards/Ali, Marco Hosfeld

Electronic Theses and Dissertations

Acute Respiratory distress Syndrome (ARDS) and Acute Lung Injury (ALI) are inflammatory lung pathologies consisting of non-hydrostatic pulmonary edema leading to hypoxia and impaired gas exchange in the lungs. ARDS/ALI is both difficult to study and treat as it is not in itself a specific pathology but rather a syndrome consisting of many pathologies that vary case by case. It is, however, consistently characterized by an explosive acute inflammatory response in the lung parenchyma leading to hypoxia. Although time has seen to an increase in the understanding of ARDS/ALI, the mortality rate remains in the range of 30-50%. For these …


Is The Walking Pattern Similar Between Slope Walking And Obstacle Negotiation?, Jiani Lu May 2021

Is The Walking Pattern Similar Between Slope Walking And Obstacle Negotiation?, Jiani Lu

Theses & Dissertations

Studying biomechanical characteristics of human motion sheds light on the motor control strategies in the central nervous system. Slope walking and obstacle negotiation appear to have some similarities in control strategies based on subjective observation, but these two motions have never been compared objectively in biomechanics literature. This study aimed to investigate the similarities between obstacle negotiation and slope walking in kinematics and muscle activity. The similarities were determined by the correlation of the maximum heel elevation and muscle co-activation index between obstacle negotiation and inclined treadmill walking. The strength of correlation was compared in four different pairs of conditions: …


Class-Incremental Learning For Wireless Device Identification In Iot, Yongxin Liu, Jian Wang, Jianqiang Li, Shuteng Niu, Houbing Song May 2021

Class-Incremental Learning For Wireless Device Identification In Iot, Yongxin Liu, Jian Wang, Jianqiang Li, Shuteng Niu, Houbing Song

Publications

Deep Learning (DL) has been utilized pervasively in the Internet of Things (IoT). One typical application of DL in IoT is device identification from wireless signals, namely Noncryptographic Device Identification (NDI). However, learning components in NDI systems have to evolve to adapt to operational variations, such a paradigm is termed as Incremental Learning (IL). Various IL algorithms have been proposed and many of them require dedicated space to store the increasing amount of historical data, and therefore, they are not suitable for IoT or mobile applications. However, conventional IL schemes can not provide satisfying performance when historical data are not …


Human Powered Vehicle Capstone, Maya L. Washington, Ryan Apolonio, Marc Sunga, John Rettenmier, Dr. Allen Wilson May 2021

Human Powered Vehicle Capstone, Maya L. Washington, Ryan Apolonio, Marc Sunga, John Rettenmier, Dr. Allen Wilson

Honors Thesis

In the ASME Human Powered Vehicle Challenge (HPVC), students design, develop, construct, and test different designs of human-powered vehicles. The design utilizes two wheels, the rear of which is responsible for power transmission from a pedal crank and braking through a disc and caliper. The design also utilizes the front wheel fork wheel for steering. Steering and braking are controlled by two levers on the handlebars. To determine whether the design was sufficient, it was compared to the standards set by ASME, including maximum weight, minimum speed, minimum turning radius, minimum ride distance, load testing, harness verification, and a complete …


Centralized Thermal Stress Oriented Dispatch Strategy For Paralleled Grid-Connected Inverters Considering Mission Profiles, Luocheng Wang, Tiefu Zhao, Jiangbiao He May 2021

Centralized Thermal Stress Oriented Dispatch Strategy For Paralleled Grid-Connected Inverters Considering Mission Profiles, Luocheng Wang, Tiefu Zhao, Jiangbiao He

Electrical and Computer Engineering Faculty Publications

One of the major failure causes in the power modules comes from the severe thermal stress in power semiconductor devices. Recently, some local control level methods have been developed to balance the power loss, dealing with the harsh mission profile, in order to reduce the thermal stress. However, there is not any specific system level strategy to leverage these local control level methods responding to the multiple inverters situation. Besides, the impacts of these methods on the thermal cycle and lifetime of the power modules in the long-term time scale have not been evaluated and compared yet. Hence, in this …


Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes, Florida Solar Energy Center, Tanvir Khan May 2021

Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes, Florida Solar Energy Center, Tanvir Khan

FSEC Energy Research Center®

Existing evidence strongly suggests that viral infectious diseases can be transmitted via an airborne route across distances in indoor environments. Accordingly, the risk of airborne transmission within homes should be managed. The public health emergency associated with SARS-CoV-2 makes controlling airborne transmission of respired viruses in indoor environments critical, especially in poorly ventilated indoor environments. The effectiveness of engineering interventions requiring minor efforts that create a negative-pressure isolation zone (IZ) for a contagious person has yet to be tested for existing residential homes.

To mitigate the risk of airborne virus transmission and maximize health protection for the population in existing …


Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes - Fact Sheet, Florida Solar Energy Center, Tanvir Khan May 2021

Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes - Fact Sheet, Florida Solar Energy Center, Tanvir Khan

FSEC Energy Research Center®

The FSEC Energy Research Center at the University of Central Florida performed research to test the effectiveness of interventions to isolate an ill person recovering from a contagious disease in a single-family home from the rest of the occupants in the home. Focus was placed on interventions requiring minor cost and effort on the part of the occupants.

DOE/GO-102021-5537, https://www.nrel.gov/docs/fy21osti/79519.pdf


Unveiling Women’S Needs And Expectations As Users Of Bike Sharing Services: The H2020 Diamond Project, Andrea Gorrini, Rawad Choubassi, Federico Messa, Wafaa Saleh, Augustus Ababio-Donkor, Maria Chiara Leva, Lorraine D'Arcy, Francesco Fabbri, David Laniado, Pablo Aragon May 2021

Unveiling Women’S Needs And Expectations As Users Of Bike Sharing Services: The H2020 Diamond Project, Andrea Gorrini, Rawad Choubassi, Federico Messa, Wafaa Saleh, Augustus Ababio-Donkor, Maria Chiara Leva, Lorraine D'Arcy, Francesco Fabbri, David Laniado, Pablo Aragon

Articles

Within the objectives of the H2020 DIAMOND project, the paper investigates women’s needs and expectations as users of the bike-sharing service managed by Syndicat Mixte Autolib et Velib Métropole in the territory of Paris Region-Petite Couronne (France). The paper presents a thematic literature review focused on gender inclusion in bike-sharing schemes. The proposed methodological approach is based on (i) Geographic Information Systems for the analysis of geolocated open datasets related to land, sociodemographic and mobility characteristics of the areas surrounding each docking stations. This was aimed at identifying a short list of suitable bike-sharing docking stations, which were further characterized …


Design Optimization Of A Pneumatic Soft Robotic Actuator Using Model-Based Optimization And Deep Reinforcement Learning, Mahsa Raeisinezhad, Nicholas Pagliocca, Behrad Koohbor, Mitja Trkov May 2021

Design Optimization Of A Pneumatic Soft Robotic Actuator Using Model-Based Optimization And Deep Reinforcement Learning, Mahsa Raeisinezhad, Nicholas Pagliocca, Behrad Koohbor, Mitja Trkov

Henry M. Rowan College of Engineering Departmental Research

We present two frameworks for design optimization of a multi-chamber pneumatic-driven soft actuator to optimize its mechanical performance. The design goal is to achieve maximal horizontal motion of the top surface of the actuator with a minimum effect on its vertical motion. The parametric shape and layout of air chambers are optimized individually with the firefly algorithm and a deep reinforcement learning approach using both a model-based formulation and finite element analysis. The presented modeling approach extends the analytical formulations for tapered and thickened cantilever beams connected in a structure with virtual spring elements. The deep reinforcement learning-based approach is …


Design Optimization Of A Pneumatic Soft Robotic Actuator Using Model-Based Optimization And Deep Reinforcement Learning, Mahsa Raeisinezhad, Nicholas Pagliocca, Behrad Koohbor, Mitja Trkov May 2021

Design Optimization Of A Pneumatic Soft Robotic Actuator Using Model-Based Optimization And Deep Reinforcement Learning, Mahsa Raeisinezhad, Nicholas Pagliocca, Behrad Koohbor, Mitja Trkov

Henry M. Rowan College of Engineering Departmental Research

We present two frameworks for design optimization of a multi-chamber pneumatic-driven soft actuator to optimize its mechanical performance. The design goal is to achieve maximal horizontal motion of the top surface of the actuator with a minimum effect on its vertical motion. The parametric shape and layout of air chambers are optimized individually with the firefly algorithm and a deep reinforcement learning approach using both a model-based formulation and finite element analysis. The presented modeling approach extends the analytical formulations for tapered and thickened cantilever beams connected in a structure with virtual spring elements. The deep reinforcement learning-based approach is …


Detecting A Heterogenous Sample Of Pigmented Melanoma Cell Lines Using Photoacoustic Flow Cytometry, Margaret Cappellano May 2021

Detecting A Heterogenous Sample Of Pigmented Melanoma Cell Lines Using Photoacoustic Flow Cytometry, Margaret Cappellano

Electronic Theses and Dissertations

Metastatic melanoma is the deadliest form of skin cancer, which is in part, attributed to its rapid aggression and lack of response to typical treatment methods. There are far too often cases where a lymph node biopsy does not detect the severity of the cancer, which in turn causes a lack of diagnosis until a mass can be visually detected on a scan, such as a PET, CT, or MRI. Once visible on a scan, the cancer is too progressive for successful treatment. To avoid this, we investigated how a blood sample can be used to negate a missed diagnosis, …


Diagnosis Of Melanoma Disease State From Patient Blood Samples Using Photoacoustic Flow Cytometry, Jacob Salvatore May 2021

Diagnosis Of Melanoma Disease State From Patient Blood Samples Using Photoacoustic Flow Cytometry, Jacob Salvatore

Electronic Theses and Dissertations

Approximately 1 in 50 Americans develop melanoma in their lifetime. Early detection of melanoma is pivotal to the survival of the patient, with a 99% survival rate for 5 or more years after an early diagnosis. Metastasis, or the spread of cancer, increases the chances of cancerous growth in other parts of the body. In this study, we propose the use of photoacoustic flow cytometry as a diagnostic of patient disease state, by closely monitoring the amount of circulating melanoma cells (CMCs) in a patient’s blood before and after chemotherapy treatments. Using this patient data, we were able to make …


Characterizing The Dormancy And Repair Of A Circumneutral Passive Remediation System Receiving Iron And Sulfate-Rich Amd, Garrett Struble May 2021

Characterizing The Dormancy And Repair Of A Circumneutral Passive Remediation System Receiving Iron And Sulfate-Rich Amd, Garrett Struble

Electronic Theses and Dissertations

The Wingfield Pines remediation system is a ~20-acre circumneutral, gravity-fed system constructed in 2009 to passively remediate Fe from an ~2000 gallon/minute effluent. In 2017, a fracture to the system’s underground cavern caused the AMD effluent to bypass the system, flowing directly into Chartiers Creek and leaving the system decommissioned between 2017-2019. Soil slurry and water samples were collected in the weeks prior to the system’s reinstalment in September 2019 through January 2020 in order to determine the effect of the repair on remediation efficiency and microbial community composition. This study acted as the first to describe the temporary decommissioning …


Smart E-Bike Conversion Kit And Helmet, Megan West, Marena Trujillo, Hossein Asghari May 2021

Smart E-Bike Conversion Kit And Helmet, Megan West, Marena Trujillo, Hossein Asghari

Honors Thesis

With many state governments across the United States implementing shutdowns to prevent the spread of COVID-19, many bike retailers have seen dramatic increases in bike sales. Electric bicycles (e-bikes) have become increasingly popular as the public searches for alternatives to public transportation. Unfortunately, e-bike users assume some risk by riding bikes that are faster than conventional bicycles. While kits to convert conventional bicycles to e-bikes exist, no “smart” e-bike/helmet kit specifically designed to keep the user safe is currently available on the market. To mitigate risks, a smart e-bike conversion kit with multiple novel safety features, including auditory and visual …


Modal Identification Of Gelatinous Structures Using Visio-Based Vibrometry, Kenneth Nwagu May 2021

Modal Identification Of Gelatinous Structures Using Visio-Based Vibrometry, Kenneth Nwagu

Honors College Theses

Gelatinous-based materials show promising uses in various fields such as tissue engineering and bioengineering. However, important structural characteristics such as natural frequencies and mode shapes of hydrogels and hydrogel-based objects are difficult to measure with conventional contact or non-contact-based techniques such as accelerometers and laser vibrometers. Solutions have been made by others using 3D laser imaging, x-ray imaging and ultrasound, but these are often expensive and have challenges in scenarios such as with translucent and small gelatinous objects. The goal of this research is to advance the state-of-the-art of characterizing structural properties of gelatinous materials by using vision based vibrometry. …


U-251mg Spheroid Generation Using A Scaffold Based Method Protocol, Lara Carroll, Brijesh K. Tiwari, James F. Curtin, Janith Wanigasekara May 2021

U-251mg Spheroid Generation Using A Scaffold Based Method Protocol, Lara Carroll, Brijesh K. Tiwari, James F. Curtin, Janith Wanigasekara

Articles

3D cell culture is a technique that is used to grow cells in vitro that will mimic an in vivo environment. 3D cell models are a helpful learning tool for researchers to better understand disease mechanisms and to explore different therapeutic properties of drugs. 3D cell cultures can be developed using patient derived cancer cells. Once they have been grown, these 3D cells can be used to screen for small molecule drugs or for genetic modification in for analysis of disease pathways or to predict drug treatments toxicity or efficacy. 3D cell cultures are a big step towards the more …


Decentralized Aggregation Design And Study Of Federated Learning, Venkata Naga Surya Sameeraja Malladi May 2021

Decentralized Aggregation Design And Study Of Federated Learning, Venkata Naga Surya Sameeraja Malladi

Master of Science in Software Engineering Theses

The advent of machine learning techniques has given rise to modern devices with built-in models for decision making and providing rich content to users. This typically involves processing huge volumes of data in central servers and sending updated models to end-user devices. There are two main concerns on this server architecture, one is the privacy of data that is being transferred to a central server and the other is volumes of data sent over the network for the model update. Federated Learning helps solve these problems by training models on local data within the device and aggregating the model with …


Real-Time Pm10 Emission Rates From Paved Roads By Measurement Of Concentrations In The Vehicle's Wake Using On-Board Sensors Part 2. Comparison Of Scamper, Traker™, Flux Measurements, And Ap-42 Silt Sampling Under Controlled Conditions, Dennis R. Fitz, Kurt Bullimer, Vic Etyemezian, Hampden D. Kuhns, John A. Gillies, George Nikolich, David E. James, Rodney Langston, Russell S. Merle Jr. May 2021

Real-Time Pm10 Emission Rates From Paved Roads By Measurement Of Concentrations In The Vehicle's Wake Using On-Board Sensors Part 2. Comparison Of Scamper, Traker™, Flux Measurements, And Ap-42 Silt Sampling Under Controlled Conditions, Dennis R. Fitz, Kurt Bullimer, Vic Etyemezian, Hampden D. Kuhns, John A. Gillies, George Nikolich, David E. James, Rodney Langston, Russell S. Merle Jr.

Civil and Environmental Engineering and Construction Faculty Research

Representative soil was evenly applied to an 800-m section of road surface. The test area was of sufficient length to allow for measurement at constant speeds of up to 72 km hr−1. SCAMPER and TRAKER™ mobile measurement vehicles made repeated test runs while an instrumented tower measured upwind-downwind horizontal PM10 flux. AP-42 methods were used to collect silt samples and calculate PM10 emission factors. Both silt loadings and vehicle speeds were varied during the experiment. Street sweeping the as-found roadway showed an initial rise in PM10 emission rates. Both TRAKER and SCAMPER measured rapid decay of PM10 emission rates after …


Device Development For Long-Term Systemic Oral Biologic Drug Delivery, Benjamin Wankum May 2021

Device Development For Long-Term Systemic Oral Biologic Drug Delivery, Benjamin Wankum

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

A biologic drug is a drug that is produced by a living organism. Biologic drugs are used to treat various medical conditions such as arthritis, diabetes, or certain forms of cancers due to their high potency and high selectivity of action. Drawbacks of biologics include their poor stability in the gastrointestinal tract and their poor absorption. In effect, this gives the drugs very low bioavailability and short therapeutic half-lives. To combat these obstacles, current delivery methods include subcutaneous injections at home or intravenous or intramuscular injections in a medical facility.

The overall scientific goal of the research was to utilize …


Pharyngeal Constriction As A Cause For Late Acquisition And Speech Sound Disorders Of Rhotic Sounds In English, Spanish, And French, Connor Mahon May 2021

Pharyngeal Constriction As A Cause For Late Acquisition And Speech Sound Disorders Of Rhotic Sounds In English, Spanish, And French, Connor Mahon

The Downtown Review: An Interdisciplinary Journal Written and Peer-Reviewed by Mandel Honors College Students at Cleveland State University

This paper attempts to explain why rhotic sounds are cross-linguistically late developing among the sound inventory of children. Included is a summary of the current literature regarding classification of rhotic sounds, an examination of the articulatory movement of the tongue root, and an overview of the clinical implications on the field of speech-language pathology. The evidence presented supports the hypothesis that pharyngeal constriction is characteristic of rhotic sounds in many languages, and that it is related to the relative late acquisition and higher rate of speech sound disorders, as seen in English, Spanish, and French.


Rocket Flight Simulation With Monte Carlo Uncertainty Analysis, Jonathan Wallace Drake May 2021

Rocket Flight Simulation With Monte Carlo Uncertainty Analysis, Jonathan Wallace Drake

Honors Capstone Projects and Theses

No abstract provided.


Robust Optimization With Recourse In Portfolio Management: Theory And Applications To Stocks And Projects, Hedieh Ashrafi, Aurelie Thiele May 2021

Robust Optimization With Recourse In Portfolio Management: Theory And Applications To Stocks And Projects, Hedieh Ashrafi, Aurelie Thiele

Operations Research and Engineering Management Theses and Dissertations

Many real-world decision problems in engineering and management have uncertain parameters. Robust optimization methodology takes into account the uncertainty in parameters of the model in the decision-making framework. In robust optimization methodology, we assume we do not know the probability distribution of parameters, and we have partial information about parameters. Portfolio management is one of those famous applications that have an uncertain environment. So, for this application, robust methodology would be a good choice. This dissertation contains three main works as the following:\\ In the first work, we provided the combination of European options and a robust optimization model to …


Modeling Hydraulic Fracturing Initiation And Propagation In Porous Rock Formationsl, Chang Huang May 2021

Modeling Hydraulic Fracturing Initiation And Propagation In Porous Rock Formationsl, Chang Huang

LSU Doctoral Dissertations

Hydraulic fracturing has long been introduced to the oil and gas industry since the early nineteenth century for both reservoir characterization and reservoir stimulation. Despite the progress made in the last two decades, many challenges still have not been tackled regarding not only the propagation problem but also the initiation problem due to its complexity. The dissertation is divided into two stages, i.e., before and after fracture initiation. The first stage of the research aimed at improving the accuracy in solving the poro-mechanical response of wellbore during fluid injection before a tensile fracture occurs, which is crucial to determine the …


Prestressed Concrete Slabs With Bonded And Unbonded Tendons, Jasmin Abdelhalim May 2021

Prestressed Concrete Slabs With Bonded And Unbonded Tendons, Jasmin Abdelhalim

Theses and Dissertations

Post-tensioning concrete technology increases the resistance of flexural concrete members. This technology allows for the production of slenderer sections, and sequentially less usage of material preserving the sustainability concept in construction engineering. Post-tensioning process can be done using bonded or unbonded steel tendons. The unbonded tendons are thought to have better resistance to corrosion for structures exposed to severe environmental conditions. The unbonded tendon’s steel strands are painted with grease and covered with plastic sheathing to prevent the moisture from reaching the steel strands thus they can provide high corrosion resistance. According to the ACI 318-19 and other codes of …


Silicon Valley 2.0 May 2021

Silicon Valley 2.0

In The Loop

The DePaul Innovation Development Lab is a collaborative ecosystem that joins business and academia in mutually beneficial, experimental enterprise. Students work in the techcentric think tank and consultancy that turns business problems into functional, testable software prototypes.


Etched-And-Regrown Diodes On M-Plane Gan For Next Generation Power Electronic Devices, Andrew A. Aragon May 2021

Etched-And-Regrown Diodes On M-Plane Gan For Next Generation Power Electronic Devices, Andrew A. Aragon

Electrical and Computer Engineering ETDs

Demand for next-generation power electronic devices is driven by continually evolving requirements of power systems. Devices utilizing III-nitride materials (GaN) and vertical selective-area doped architectures are advantageous due to their wide- bandgap, thermal management, small form-factor, and current handling.

Such devices incorporate junctions at multiple crystalline planes. Thus, effects of impurity contamination and etch damage are investigated on the m-plane (10-10) of GaN. Impurites (Si, O, and C) are shown to reduce blocking voltage (~ 102 ×) and increase forward leakage current (~ 104 ×) in regrown versus continuously-grown p-n diodes. Elevated deep level defects at Ec – …