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Full-Text Articles in Engineering

Spectral Clustering For Electrical Phase Identification Using Advanced Metering Infrastructure Voltage Time Series, Logan Blakely Jan 2019

Spectral Clustering For Electrical Phase Identification Using Advanced Metering Infrastructure Voltage Time Series, Logan Blakely

Dissertations and Theses

The increasing demand for and prevalence of distributed energy resources (DER) such as solar power, electric vehicles, and energy storage, present a unique set of challenges for integration into a legacy power grid, and accurate models of the low-voltage distribution systems are critical for accurate simulations of DER. Accurate labeling of the phase connections for each customer in a utility model is one area of grid topology that is known to have errors and has implications for the safety, efficiency, and hosting capacity of a distribution system. This research presents a methodology for the phase identification of customers solely using …


Application Of Improved Feature Selection Algorithm In Svm Based Market Trend Prediction Model, Qi Li Jan 2019

Application Of Improved Feature Selection Algorithm In Svm Based Market Trend Prediction Model, Qi Li

Dissertations and Theses

In this study, a Prediction Accuracy Based Hill Climbing Feature Selection Algorithm (AHCFS) is created and compared with an Error Rate Based Sequential Feature Selection Algorithm (ERFS) which is an existing Matlab algorithm. The goal of the study is to create a new piece of an algorithm that has potential to outperform the existing Matlab sequential feature selection algorithm in predicting the movement of S&P 500 (^GSPC) prices under certain circumstances. The two algorithms are tested based on historical data of ^GSPC, and Support Vector Machine (SVM) is employed by both as the classifier. A prediction without feature selection algorithm …


From Drought To Food-Energy-Water-Security Nexus: An Assessment Of Food Insecurity In The Middle East, Maysoun Ayad Hameed Jan 2019

From Drought To Food-Energy-Water-Security Nexus: An Assessment Of Food Insecurity In The Middle East, Maysoun Ayad Hameed

Dissertations and Theses

Drought is an extreme climate phenomenon that happens slowly and periodically threatens the environmental and socio-economic sectors. Developing countries have experienced crucial conditions in meeting the needs for food, energy, and water security. Natural disasters contribute as risky sources of food insecurity and vulnerability in the Middle East. This dissertation presents a country-level review and quantitative assessment of the current issues associated with the Food-Energy-Water-Security (FEWS) Nexus in the Middle East. In this study, sixteen countries in the Middle East are chosen, namely, Arabian Peninsula, Iran, Syria, Lebanon, Israel, Palestine, Egypt, and Turkey. The most recent datasets are used to …


Good Similar Patches For Image Denoising (Poster), Si Lu Jan 2019

Good Similar Patches For Image Denoising (Poster), Si Lu

Computer Science Faculty Publications and Presentations

Patch-based denoising algorithms like BM3D have achieved outstanding performance. An important idea for the success of these methods is to exploit the recurrence of similar patches in an input image to estimate the underlying image structures....


Bigger Tides, Less Flooding: Effects Of Dredging On Barotropic Dynamics In A Highly Modified Estuary, David K. Ralston, Stefan Talke, W. Rockwell Geyer, Hussein A. M. Al-Zubaidi, Christopher K. Sommerfield Jan 2019

Bigger Tides, Less Flooding: Effects Of Dredging On Barotropic Dynamics In A Highly Modified Estuary, David K. Ralston, Stefan Talke, W. Rockwell Geyer, Hussein A. M. Al-Zubaidi, Christopher K. Sommerfield

Civil and Environmental Engineering Faculty Publications and Presentations

Since the late nineteenth century, channel depths have more than doubled in parts of New York Harbor and the tidal Hudson River, wetlands have been reclaimed and navigational channels widened, and river flow has been regulated. To quantify the effects of these modifications, observations and numerical simulations using historical and modern bathymetry are used to analyze changes in the barotropic dynamics. Model results and water level records for Albany (1868 to present) and New York Harbor (1844 to present) recovered from archives show that the tidal amplitude has more than doubled near the head of tides, whereas increases in the …


Evaluation Of Shared Space To Reduce Traffic Congestion, Kimley Frosch, David Martinelli, Avinash Unnikrishnan Jan 2019

Evaluation Of Shared Space To Reduce Traffic Congestion, Kimley Frosch, David Martinelli, Avinash Unnikrishnan

Civil and Environmental Engineering Faculty Publications and Presentations

Pedestrian and vehicle interactions often lead to conflicts that bring about safety, traffic congestion, and priority or right of way issues. Common methods used in the past to combat said issues have largely relied on the principle of separating the motions of pedestrians and vehicles by means of bridges, tunnels, signals, and access restrictions. A different approach known as shared space aims to solve the same problems with a less structured and defined environment which instead places more reliance on human interaction and perception. Although it has been used in multiple scenarios across Europe with success, instances of shared spaces …


The Tides They Are A-Changin’: A Comprehensive Review Of Past And Future Nonastronomical Changes In Tides, Their Driving Mechanisms And Future Implications, Ivan D. Haigh, Mark D. Pickering, J.A. Mattias Green, Brian K. Arbic, Arne Arns, Soenke Dangendorf, David Hill, David A. Jay, Multiple Additional Authors Jan 2019

The Tides They Are A-Changin’: A Comprehensive Review Of Past And Future Nonastronomical Changes In Tides, Their Driving Mechanisms And Future Implications, Ivan D. Haigh, Mark D. Pickering, J.A. Mattias Green, Brian K. Arbic, Arne Arns, Soenke Dangendorf, David Hill, David A. Jay, Multiple Additional Authors

Civil and Environmental Engineering Faculty Publications and Presentations

Scientists and engineers have observed for some time that tidal amplitudes at many locations are shifting considerably due to non-astronomical factors. Here we review comprehensively these important changes in tidal properties, many of which remain poorly understood. Over long geological time-scales, tectonic processes drive variations in basin size, depth, and shape, and hence the resonant properties of ocean basins. On shorter geological time-scales, changes in oceanic tidal properties are dominated by variations in water depth. A growing number of studies have identified widespread, sometimes regionally-coherent, positive and negative trends in tidal constituents and levels during the 19th, 20th and early …


Investigate An Appropriate Spatial Resolution For Large-Scaled Pedestrian Travel Demand Model, Qin Zhang, Kelly Clifton, Rolf Moeckel Jan 2019

Investigate An Appropriate Spatial Resolution For Large-Scaled Pedestrian Travel Demand Model, Qin Zhang, Kelly Clifton, Rolf Moeckel

Civil and Environmental Engineering Faculty Publications and Presentations

An appropriate spatial resolution plays a significant role in any travel demand models. It directly impacts the level of detail of model input data, outcomes, and sensitivities (Castiglione et al., 2014; Moeckel and Donnelly, 2015). Compared to motorized or bicycle travel, pedestrian trips occur over a shorter travel distance and they are sensitive to environmental conditions at a much finer grain. Thus, it is important for models to set an appropriate spatial resolution to capture variations in walking conditions, leading to better representation of pedestrian demand over space (Gehrke and Clifton, 2014).


Observational Method And Coding Framework For Analyzing The Functionality Of Unprotected Bicycle Lanes, Cat Silva, Kelly Clifton, Rolf Moeckel Jan 2019

Observational Method And Coding Framework For Analyzing The Functionality Of Unprotected Bicycle Lanes, Cat Silva, Kelly Clifton, Rolf Moeckel

Civil and Environmental Engineering Faculty Publications and Presentations

This research evaluates how well unprotected bicycle lanes function as dedicated travel lanes for bicyclists. Two types of bicycle lanes are included in this study, including on-street bicycle lanes demarcated with painted lines on the vehicular roadway and bicycle lanes at-grade with, and immediately adjacent to, the pedestrian sidewalk. Specifically, the research is focused on how people behave and interact on street segments with these facilities in place. To assess how, and how well, these types of bicycle lanes function for the bicyclists using them, an observational method is deployed to record, document, and analyze people’s behavior and interactions. A …


Neuromechanical Model Of Rat Hindlimb Walking With Two-Layer Cpgs, Kaiyu Deng, Nicholas Szczecinski, Dirk Arnold, Emanuel Andrada, Martin Fischer, Roger Quinn, Alexander J. Hunt Jan 2019

Neuromechanical Model Of Rat Hindlimb Walking With Two-Layer Cpgs, Kaiyu Deng, Nicholas Szczecinski, Dirk Arnold, Emanuel Andrada, Martin Fischer, Roger Quinn, Alexander J. Hunt

Mechanical and Materials Engineering Faculty Publications and Presentations

This work demonstrates a neuromechanical model of rat hindlimb locomotion undergoing nominal walking with perturbations. In the animal, two types of responses to perturbations are observed: resetting and non-resetting deletions. This suggests that the animal locomotor system contains a memory-like organization. To model this phenomenon, we built a synthetic nervous system that uses separate rhythm generator and pattern formation layers to activate antagonistic muscle pairs about each joint in the sagittal plane. Our model replicates the resetting and non-resetting deletions observed in the animal. In addition, in the intact (i.e., fully afferented) rat walking simulation, we observe slower recovery after …


Modeling Changes In Public Transit And Private-For-Hire Usage When Implementing A Spatial Tax, Ty Lazarchik Jan 2019

Modeling Changes In Public Transit And Private-For-Hire Usage When Implementing A Spatial Tax, Ty Lazarchik

REU Final Reports

Private-for-Hire (PfH) transportation options, such as Uber, Lyft, and taxicabs, are consistently growing in popularity. With this expanded utilization, cities are struggling to maintain usage of their public transit systems. While PfH transportation has been heavily researched, there is a need to further study how its effects on transit usage may be minimized. In this paper, previous work in traffic modeling and analysis of transit and PfH differences are expanded to develop an agent-based decision model in order to simulate and analyze the effectiveness of implementing a location-based tax in and around the city center of Portland, Oregon. The results …


Overview Of Homechem: House Observations Of Microbial And Environmental Chemistry, Delphine K. Farmer, Marina E. Vance, Jon P. D. Abbatt, Andrew Abeleira, Michael R. Alves, Richard Corsi, Peter F. Decarlo, Allen H. Goldstein, Vicki H. Grassian, Lea Hildebrandt Ruiz, Jose L. Jimenez, Tara Kahan, Multiple Additional Authors Jan 2019

Overview Of Homechem: House Observations Of Microbial And Environmental Chemistry, Delphine K. Farmer, Marina E. Vance, Jon P. D. Abbatt, Andrew Abeleira, Michael R. Alves, Richard Corsi, Peter F. Decarlo, Allen H. Goldstein, Vicki H. Grassian, Lea Hildebrandt Ruiz, Jose L. Jimenez, Tara Kahan, Multiple Additional Authors

Mechanical and Materials Engineering Faculty Publications and Presentations

The House Observations of Microbial and Environmental Chemistry (HOMEChem) study is a collaborative field investigation designed to probe how everyday activities influence the emissions, chemical transformations and removal of trace gases and particles in indoor air. Sequential and layered experiments in a research house included cooking, cleaning, variable occupancy, and window-opening. This paper describes the overall design of HOMEChem and presents preliminary case studies investigating the concentrations of reactive trace gases, aerosol particles, and surface films. Cooking was a large source of VOCs, CO2, NOx, and particles. By number, cooking particles were predominantly in the ultrafine mode. Organic aerosol dominated …


Planning For Change In The Electric Power Industry: A Primer For Transactive Energy Scenario Development, Joshua Binus Jan 2019

Planning For Change In The Electric Power Industry: A Primer For Transactive Energy Scenario Development, Joshua Binus

Engineering and Technology Management Faculty Publications and Presentations

The electric power industry and its associated infrastructures (a.k.a. "the grid") are evolving from centrally planned, organized, and operated networks of players, technologies, and resources to systems of systems that are increasingly digitized and distributed in their operation and innovative capacity. Subsequently, strategic planners and technology managers associated with the electric power industry are faced with a range of scenarios to evaluate, including one that considers the emergence of commercialized transactive energy systems in the coming ten-year time horizon. The crafting of a transactive energy scenario can help inform technology innovation and management efforts that benefit consumers, electricity providers, and …


Technological Cooperation Network In Biotechnology Analysis Of Patents With Brazil As The Priority Country, Cristiano Goncalves Pereira, Rodrigo Ribeiro Da Silva, Joao Ricardo Lavoie, Geciane Silveira Porto Jan 2019

Technological Cooperation Network In Biotechnology Analysis Of Patents With Brazil As The Priority Country, Cristiano Goncalves Pereira, Rodrigo Ribeiro Da Silva, Joao Ricardo Lavoie, Geciane Silveira Porto

Engineering and Technology Management Faculty Publications and Presentations

Purpose – The establishment of partnerships between companies, government and universities aims to enhance innovation and the technological development of institutions. The biotechnology sector has grown in recent years mainly driven by its cooperative business model. Compared to other countries, this sector is slowly advancing in Brazil, with delays in science, technology and innovation, especially in the private sector. This paper aims to examine, through social network analysis, the collaborative networks between institutions that filed patents in biotechnology – medicinal preparations from plants – whose inventions had Brazil as the priority country. Design/methodology/approach – The study of technological cooperation using …


A Preliminary Strategic Framework For Enhancing The Sustainability Of International Technology Transfer: The Case Of Libya, Rafaa Ibrahim Khalifa, Maoloud Dabab, Husam Barham Jan 2019

A Preliminary Strategic Framework For Enhancing The Sustainability Of International Technology Transfer: The Case Of Libya, Rafaa Ibrahim Khalifa, Maoloud Dabab, Husam Barham

Engineering and Technology Management Faculty Publications and Presentations

International Technology Transfer (ITT) has played a crucial role not only in the industrial growth of developing countries but also in enhancing the competitiveness of their enterprises in the global market. Libya is a North African country that is currently shifting from a strictly petroleum/mineral based economy to a broad-based economy competing with distinct advantages through selecting, planning, and adopting the right technology for the domestic market. This significant transition requires strategic access to global technology transfer. In this paper, a preliminary strategic framework is designed to enhance the sustainability of the ITT process from international donators to the Country …


Cybersecurity Planning For Artificial Intelligent Systems In Space, Gary Langford, Lucas Beaulieu, Jeffery Carpenter, Ian Watkins, Brock Marsh, Teah Heidorn, Chris Chase Jan 2019

Cybersecurity Planning For Artificial Intelligent Systems In Space, Gary Langford, Lucas Beaulieu, Jeffery Carpenter, Ian Watkins, Brock Marsh, Teah Heidorn, Chris Chase

Engineering and Technology Management Faculty Publications and Presentations

CubeSats continue to proliferate and are an excellent low-cost method of remote sensing. A key piece of intelligent systems is sensory input, data storage, and data communications. With the continued miniaturization of technology, CubeSats will increase their sensory inputs with future miniaturization and enhance their robustness for autonomous operations if data and communications are secure. These futures inspire an intelligent system solution to on-orbit communications. This paper explores a dual-microprocessor approach to improve hardware cybersecurity of intelligent systems, with a view toward intensional intelligence as a means of adjudicating access to sensitive data onboard the CubeSat. With enhanced cybersecurity, Artificial …


Capital Efficiency For Development Stage Biotech-Based Firms: An Ipo Perspective, Mark J. Ahn, Amir Shaygan Jan 2019

Capital Efficiency For Development Stage Biotech-Based Firms: An Ipo Perspective, Mark J. Ahn, Amir Shaygan

Engineering and Technology Management Faculty Publications and Presentations

Access to multiple tranches of capital is critical for predominantly no revenue development stage biotech firms. While financing needs are monotonically increasing over multiple years in the product development approval cycle, the market for high risk, milestone driven biotech investment is significantly more volatile than the financial markets as a whole. In this paper, we analyzed the role and relative importance of global biotech IPOs, as well as other sources of capital such as strategic alliances, for research and development funding. We also explored and assessed the degree of mismatch between the access to capital, operational efficiencies, and how firms …


No-Reference Image Denoising Quality Assessment, Si Lu Jan 2019

No-Reference Image Denoising Quality Assessment, Si Lu

Computer Science Faculty Publications and Presentations

A wide variety of image denoising methods are available now. However, the performance of a denoising algorithm often depends on individual input noisy images as well as its parameter setting. In this paper, we present a noreference image denoising quality assessment method that can be used to select for an input noisy image the right denoising algorithm with the optimal parameter setting. This is a challenging task as no ground truth is available. This paper presents a data-driven approach to learn to predict image denoising quality. Our method is based on the observation that while individual existing quality metrics and …


Monitored Indoor Environmental Quality Of A Mass Timber Office Building: A Case Study, Jason Stenson, Suzanne L. Ishaque, Aurélie Laguerre, Andrew Loia, Georgia Maccrone, Ignace Mugabo, Dale Northcutt, Mariapaola Riggio, Andre Barbosa, Elliott T. Gall, Kevin Van Den Wymelenberg Jan 2019

Monitored Indoor Environmental Quality Of A Mass Timber Office Building: A Case Study, Jason Stenson, Suzanne L. Ishaque, Aurélie Laguerre, Andrew Loia, Georgia Maccrone, Ignace Mugabo, Dale Northcutt, Mariapaola Riggio, Andre Barbosa, Elliott T. Gall, Kevin Van Den Wymelenberg

Mechanical and Materials Engineering Faculty Publications and Presentations

A broad range of building performance monitoring, sampling, and evaluation was conducted periodically after construction and spanning more than a year, for an occupied office building constructed using mass timber elements such as cross-laminated timber (CLT) floor and roof panels, as well as glue-laminated timber (GLT) beams and columns. This case study contributes research on monitoring indoor environmental quality in buildings, describing one of the few studies of an occupied mass timber building, and analyzing data in three areas that impact occupant experience: indoor air quality, bacterial community composition, and floor vibration. As a whole, the building was found to …


Improvement Of The Tribological Characteristics Of Aisi 8620, 8640 And 52100 Steels Through Thermo-Reactive Treatments, Rafael Magalhães Triani, Fábio Edson Mariani, Lucas Fuscaldi De Assis Gomes, Pedro Gabriel Bonella De Oliveira, George E. Totten, Luiz Carlos Casteletti Jan 2019

Improvement Of The Tribological Characteristics Of Aisi 8620, 8640 And 52100 Steels Through Thermo-Reactive Treatments, Rafael Magalhães Triani, Fábio Edson Mariani, Lucas Fuscaldi De Assis Gomes, Pedro Gabriel Bonella De Oliveira, George E. Totten, Luiz Carlos Casteletti

Mechanical and Materials Engineering Faculty Publications and Presentations

The production of vanadium and niobium carbides (VC and NbC) layers on AISI 8620, 8640, and 52100 steels may increase hardness and wear resistance of substrates. Thermochemical treatments were performed at 1000 °C for 2 and 4 h. The characterization of the treated samples was carried out by means of Knoop microhardness tests, “calotest” type microadhesive wear test, layer adhesion test according to VDI 3198 standard, and X-ray diffraction. Compact and uniform layers of VC and NbC were obtained in all treatments, with hardness up to 2500 HK and microadhesive wear resistance far superior to that of the substrates, indicating …


Plasma-Enhanced Chemical Vapor Deposition Of Acetylene On Codeposited Bimetal Catalysts Increasing Graphene Sheet Continuity Under Low-Temperature Growth Conditions, Joshua Tracy, Otto Zietz, Samuel Olson, Jun Jiao Jan 2019

Plasma-Enhanced Chemical Vapor Deposition Of Acetylene On Codeposited Bimetal Catalysts Increasing Graphene Sheet Continuity Under Low-Temperature Growth Conditions, Joshua Tracy, Otto Zietz, Samuel Olson, Jun Jiao

Mechanical and Materials Engineering Faculty Publications and Presentations

Here, we report a novel method for low-temperature synthesis of monolayer graphene at 450 °C on a polycrystalline bimetal Ni-Au catalyst. In this study, low-temperature chemical vapor deposition synthesis of graphene was performed at 450 °C on codeposited Ni-Au which shows successful monolayer graphene formation without an extra annealing process. The experimental results suggest that electron beam codeposition of bimetal catalyst is the key procedure that enables the elimination of the pre-growth high-temperature annealing of the catalyst prior to graphene synthesis, an indispensable process, used in previous reports. The formation was further improved by plasma-assisted growth in which the inductively …


Accumulation Of Di-2-Ethylhexyl Phthalate From Polyvinyl Chloride Flooring Into Settled House Dust And The Effect On The Bacterial Community, Samantha Velazquez, Chenyang Bi, Jeff Kline, Susie Nunez, Richard Corsi, Ying Xu, Suzanne L. Ishaque Jan 2019

Accumulation Of Di-2-Ethylhexyl Phthalate From Polyvinyl Chloride Flooring Into Settled House Dust And The Effect On The Bacterial Community, Samantha Velazquez, Chenyang Bi, Jeff Kline, Susie Nunez, Richard Corsi, Ying Xu, Suzanne L. Ishaque

Mechanical and Materials Engineering Faculty Publications and Presentations

Di-2-ethylhexyl phthalate (DEHP) is a plasticizer used in consumer products and building materials, including polyvinyl chloride flooring material. DEHP adsorbs from material and leaches into soil, water, or dust and presents an exposure risk to building occupants by inhalation, ingestion, or absorption. A number of bacterial isolates are demonstrated to degrade DEHP in culture, but bacteria may be susceptible to it as well, thus this study examined the relation of DEHP to bacterial communities in dust. Polyvinyl chloride flooring was seeded with homogenized house dust and incubated for up to 14 days, and bacterial communities in dust were identified at …


Mechanics And Historical Evolution Of Sea Level Blowouts In New York Harbor, Praneeth Gurumurthy, Philip Orton, Stefan A. Talke, Nickitas Georgas, James F. Booth Jan 2019

Mechanics And Historical Evolution Of Sea Level Blowouts In New York Harbor, Praneeth Gurumurthy, Philip Orton, Stefan A. Talke, Nickitas Georgas, James F. Booth

Civil and Environmental Engineering Faculty Publications and Presentations

Wind-induced sea level blowouts, measured as negative storm surge or extreme low water (ELW), produce public safety hazards and impose economic costs (e.g., to shipping). In this paper, we use a regional hydrodynamic numerical model to test the effect of historical environmental change and the time scale, direction, and magnitude of wind forcing on negative and positive surge events in the New York Harbor (NYH). Environmental sensitivity experiments show that dredging of shipping channels is an important factor affecting blowouts while changing ice cover and removal of other roughness elements are unimportant in NYH. Continuously measured water level records since …


Spatial Fingerprinting Of Biogenic And Anthropogenic Volatile Organic Compounds In An Arid Unsaturated Zone, Christopher T. Green, Wentai Luo, Christopher H. Conaway, Karl B. Haase, Ronald J. Baker Jan 2019

Spatial Fingerprinting Of Biogenic And Anthropogenic Volatile Organic Compounds In An Arid Unsaturated Zone, Christopher T. Green, Wentai Luo, Christopher H. Conaway, Karl B. Haase, Ronald J. Baker

Chemistry Faculty Publications and Presentations

Subsurface volatile organic compounds (VOCs) can pose risks to human and environmental health and mediate biological processes. Volatile organic compounds have both anthropogenic and biogenic origins, but the relative importance of these sources has not been explored in subsurface environments. This study synthesized 17 yr of VOC data from the Amargosa Desert Research Site in Nevada with the goal of improving understanding of spatial and temporal variations that distinguish sources of VOCs from a landfill and from ambient sources including biogenic VOCs (bVOCs). Gas samples were collected from 1999 to 2016 from an array of shallow sample points (0.5- and …


Performance Of Plunge Depth Control Methods During Friction Stir Welding, Jinyoung Yoon, Cheolhee Kim, Sehun Rhee Jan 2019

Performance Of Plunge Depth Control Methods During Friction Stir Welding, Jinyoung Yoon, Cheolhee Kim, Sehun Rhee

Mechanical and Materials Engineering Faculty Publications and Presentations

Friction stir welding is a preferred solid state welding process for Al/Fe joints, and in friction stir lap welding, the plunge depth is the most critical parameter for joint strength. We compared three plunge depth control methods, namely conventional position control, offset position control, and deflection compensation control in the friction stir lap welding of 3 mm-thick Al 5083-O alloy over 1.2 mm-thick DP 590 steel. The desired plunge depth was 0.2 mm into the steel sheet. However, the pin did not reach the steel surface under conventional position control due to deflection of the vertical axis of the welding …


Simulation To Fabrication—Understanding The Effect Of Niaucu Alloy Catalysts For Controlled Growth Of Graphene At Reduced Temperature, Huahan Zhan, Bin Jiang, Otto Zietz, Samuel Olson, Jun Jiao Jan 2019

Simulation To Fabrication—Understanding The Effect Of Niaucu Alloy Catalysts For Controlled Growth Of Graphene At Reduced Temperature, Huahan Zhan, Bin Jiang, Otto Zietz, Samuel Olson, Jun Jiao

Mechanical and Materials Engineering Faculty Publications and Presentations

It is a significant challenge to grow large-scale, high quality, monolayer graphene at low temperature for the applications in industry, especially for the complementary metal oxide semiconductor fabrication process. To overcome this difficulty, we simulated the decomposition of acetylene (C2H2) on (100) surfaces of primarily nickel (Ni) catalysts with small mol fractions of gold (Au) and copper (Cu), using a 4 × 4 × 4 periodic supercell model. Based on the calculation of the reaction energies to decompose the C-H or C≡C bonds on different catalyst surfaces, a differential energy is proposed to clearly scale the decomposition difficulties such that …


Exploring And Expanding The One-Pixel Attack, Umairullah Khan, Walt Woods Jan 2019

Exploring And Expanding The One-Pixel Attack, Umairullah Khan, Walt Woods

Maseeh Summer Undergraduate Research Experience

In machine learning research, adversarial examples are normal inputs to a classifier that have been specifically perturbed to cause the model to misclassify the input. These perturbations rarely affect the human readability of an input, even though the model’s output is drastically different. Recent work has demonstrated that image-classifying deep neural networks (DNNs) can be reliably fooled with the modification of a single pixel in the input image, without knowledge of a DNN’s internal parameters. This “one-pixel attack” utilizes an iterative evolutionary optimizer known as differential evolution (DE) to find the most effective pixel to perturb, via the evaluation of …


Benchmarking And Evaluating The Efficiency Of Mass Transit Systems Based On Best Practice Using Data Envelopment Analysis, Jacqueline Nayame, Maoloud Dabab, Timothy Anderson Jan 2019

Benchmarking And Evaluating The Efficiency Of Mass Transit Systems Based On Best Practice Using Data Envelopment Analysis, Jacqueline Nayame, Maoloud Dabab, Timothy Anderson

Engineering and Technology Management Faculty Publications and Presentations

Public transit systems in the USA have been faced with mounting pressure to decrease their operating costs while at the same time expected to increase ridership and meeting multiple societal needs. The primary objective of this study is to measure the efficiencies of mass transit agencies based on best practice in the US, identify the influencing factors leading to their efficiencies, and how these strategies and policies can be used improve inefficiency in transit agencies. Using Data Envelopment Analysis (DEA) method, the study analyzed the mass performance of 334 transit agencies across the US using data from the national transit …


Using Homing, Synchronizing And Distinguishing Input Sequences For The Analysis Of Reversible Finite State Machines, Martin Lukac, Michitaka Kameyama, Marek A. Perkowski, Pawel Kerntopf Jan 2019

Using Homing, Synchronizing And Distinguishing Input Sequences For The Analysis Of Reversible Finite State Machines, Martin Lukac, Michitaka Kameyama, Marek A. Perkowski, Pawel Kerntopf

Electrical and Computer Engineering Faculty Publications and Presentations

A digital device is called reversible if it realizes a reversible mapping, i.e., the one for which there exist a unique inverse. The field of reversible computing is devoted to studying all aspects of using and designing reversible devices. During last 15 years this field has been developing very intensively due to its applications in quantum computing, nanotechnology and reducing power consumption of digital devices. We present an analysis of the Reversible Finite State Machines (RFSM) with respect to three well known sequences used in the testability analysis of the classical Finite State Machines (FSM). The homing, distinguishing and synchronizing …


Machine-Learning Based Three-Qubit Gate For Realization Of A Toffoli Gate With Cqed-Based Transmon Systems, Sahar Daraeizadeh, Shavindra Premaratne, Xiaoyu Song, Marek A. Perkowski, Anne Y. Matsuura Jan 2019

Machine-Learning Based Three-Qubit Gate For Realization Of A Toffoli Gate With Cqed-Based Transmon Systems, Sahar Daraeizadeh, Shavindra Premaratne, Xiaoyu Song, Marek A. Perkowski, Anne Y. Matsuura

Electrical and Computer Engineering Faculty Publications and Presentations

We use machine learning techniques to design a 50 ns three-qubit flux-tunable controlled-controlled-phase gate with fidelity of >99.99% for nearest-neighbor coupled transmons in circuit quantum electrodynamics architectures. We explain our gate design procedure where we enforce realistic constraints, and analyze the new gate’s robustness under decoherence, distortion, and random noise. Our controlled-controlled phase gate in combination with two single-qubit gates realizes a Toffoli gate which is widely used in quantum circuits, logic synthesis, quantum error correction, and quantum games.