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Articles 92641 - 92670 of 197988

Full-Text Articles in Engineering

14-05 Development Of Decision Support Tools To Assess Pedestrian And Bicycle Safety: Development Of Safety Performance Functions, Valerian Kwigizile, Jun-Seok Oh, Ron Van Houten, Keneth Morgan Kwayu Nov 2016

14-05 Development Of Decision Support Tools To Assess Pedestrian And Bicycle Safety: Development Of Safety Performance Functions, Valerian Kwigizile, Jun-Seok Oh, Ron Van Houten, Keneth Morgan Kwayu

Transportation Research Center Reports

While a number of studies have developed Safety Performance Functions (SPFs) for motorized traffic, there has been a very limited focus on developing SPFs for non-motorized traffic. Lack of exposure measures for pedestrians and bicyclists has been cited often as the obstacle to developing reliable SPFs. This project aimed at developing statewide SPFs for bicyclists and pedestrians at urban intersections. The SPFs developed can be used as a decision supporting tool for planners and practitioners in prioritizing areas for safety improvements. In order to capture crash patterns despite, a carefully designed sampling approach was implemented and improvements on other aspects …


Ev Workplace Charging Energy Use And Cost Case Study, Florida Solar Energy Center, Richard Raustad Nov 2016

Ev Workplace Charging Energy Use And Cost Case Study, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

Efforts to increase the availability of plug-in electric vehicle (PEV) charging stations have focused on expanding public charging stations, promoting charging at the workplace and using charging stations as a shopping incentive for retail stores. This report examines the costs and energy uses to provide the charging service. Rapidly charging a PEV requires expensive electric equipment and can lead to high operating costs due to electrical demand charges. This project presents results from a detailed case study for 5 PEV chargers where the charger electricity costs are a part of a facilities electric bill. Also presented are options for minimizing …


Usu Students Outshine Peers In National Scholarship Challenge | College Of Engineering, Usu College Of Engineering Nov 2016

Usu Students Outshine Peers In National Scholarship Challenge | College Of Engineering, Usu College Of Engineering

College of Engineering News

News Release – LOGAN, UTAH, Nov. 15, 2016 – Students and faculty at Utah State University’s College of Engineering are celebrating an unusual success. This fall, eight engineering students received prestigious scholarship awards from the American Nuclear Society – a significant accomplishment considering USU does not have a nuclear engineering program.

But the university is no stranger to the topic. Two engineering researchers here recently received major research funding from the U.S. Department of Energy totaling $5.8 million, and several other engineering faculty at USU are considered top experts in nuclear engineering fields.


Interaction Between The Stress Phase Angle (Spa) And The Oscillatory Shear Index (Osi) Affects Endothelial Cell Gene Expression, Ronny Amaya, Limary M. Cancel, John M. Tarbell Nov 2016

Interaction Between The Stress Phase Angle (Spa) And The Oscillatory Shear Index (Osi) Affects Endothelial Cell Gene Expression, Ronny Amaya, Limary M. Cancel, John M. Tarbell

Publications and Research

Hemodynamic forces play an important role in the non-uniform distribution of atherosclerotic lesions. Endothelial cells are exposed simultaneously to fluid wall shear stress (WSS) and solid circumferential stress (CS). Due to variations in impedance (global factors) and geometric complexities (local factors) in the arterial circulation a time lag arises between these two forces that can be characterized by the temporal phase angle between CS and WSS (stress phase angle±SPA). Asynchronous flows (SPA close to -180Ê) that are most prominent in coronary arteries have been associated with localization of atherosclerosis. Reversing oscillatory flows characterized by an oscillatory shear index (OSI) that …


Quantum Dot Band Gap Investigations, John Ryan Peterson Nov 2016

Quantum Dot Band Gap Investigations, John Ryan Peterson

Student Works

Improving solar panel efficiency has become increasingly important as the world searches for cheap renewable energy. Recent developments in the industry have focused on multi-layer cells, some of which use semiconducting dyes to absorb light in place of crystalline solids. In this paper, I characterize various dyes recently synthesized for use in solar panels. These dyes contain semiconducting nanoparticles enclosed primarily by the protein ferritin to limit particle size. The band gaps were measured using either optical absorption spectroscopy or measuring the photoluminescence spectrum, depending on the type of semiconductor. The results indicate that both manganese oxide and lead sulfide …


Automatic Segmentation Of Coronal Holes In Solar Images And Solar Prediction Map Classification, Venkatesh Jatla Nov 2016

Automatic Segmentation Of Coronal Holes In Solar Images And Solar Prediction Map Classification, Venkatesh Jatla

Electrical and Computer Engineering ETDs

Solar image analysis relies on the detection of coronal holes for predicting disruptions to earth’s magnetic field. The coronal holes act as sources of solar wind that can reach the earth. Thus, coronal holes are used in physical models for predicting the evolution of solar wind and its potential for interfering with the earth’s magnetic field. Due to inherent uncertainties in the physical models, there is a need for a classification system that can be used to select the physical models that best match the observed coronal holes. The physical model classification problem is decomposed into three subproblems. First, the …


Antimonide-Based Superlattice Membranes For Infrared Applications, Seyedeh Marziyeh Zamiri Nov 2016

Antimonide-Based Superlattice Membranes For Infrared Applications, Seyedeh Marziyeh Zamiri

Electrical and Computer Engineering ETDs

Semiconductor membranes offer an interesting materials and device development platform due to their ability to integrate dissimilar materials through a print, stamp and transfer process. There is a lot of interest in integrating antimonide based type-II superlattices (T2SL) onto inexpensive substrates, such as Si, to not only undertake fundamental studies into the optical, electronic and structural properties of the superlattices but also to fabricate wafer-level infrared (IR) photodetectors. An effective approach to transfer type-II superlattice membranes (T2SL-M) onto alternate substrates is based on membrane release from the native GaSb substrate followed by the transfer to a new host substrate. In …


Fabrication Of High Performing Pemfc Catalyst-Coated Membranes With A Low Cost Air-Assisted Cylindrical Liquid Jets Spraying System, Xiong Peng, Travis Omasta, William Rigdon, William E. Mustain Nov 2016

Fabrication Of High Performing Pemfc Catalyst-Coated Membranes With A Low Cost Air-Assisted Cylindrical Liquid Jets Spraying System, Xiong Peng, Travis Omasta, William Rigdon, William E. Mustain

Faculty Publications

In this work, a low cost air-assisted cylindrical liquid jets spraying (ACLJS) system was developed to prepare high-performance catalyst-coated membranes (CCMs) for proton exchange membrane fuel cells (PEMFCs). The catalyst ink was flowed from a cylindrical orifice and was atomized by an air stream fed from a coaxial slit and sprayed directly onto the membrane, which was suctioned to a heated aluminum vacuum plate. The CCM pore architecture including size, distribution and volume can be controlled using various flow parameters, and the impact of spraying conditions on electrode structure and PEMFC performance was investigated. CCMs fabricated in the fiber-type break-up …


Investigation Of Self-Organizing Traffic Signal Control With Graphical Signal Performance Measures, Christopher M. Day, Darcy M. Bullock Nov 2016

Investigation Of Self-Organizing Traffic Signal Control With Graphical Signal Performance Measures, Christopher M. Day, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

Adaptive signal control is the subject of an increasing amount of research, as well as development and implementation. Most existing adaptive control systems achieve coordination by applying system control as a constraining layer on top of local control. Some researchers have suggested that, with the right local-control logic, coordination might be achieved as an dynamically emergent phenomenon without the need for a management layer. This paper explores the potential of a self-organizing signal control algorithm using a variety of performance measures. First, the initially reported algorithm performance is reproduced in an idealized environment; next, the algorithm is applied in a …


Novel Magnetic Nanostructures For Enhanced Magnetic Hyperthermia Cancer Therapy, Zohreh Nemati Porshokouh Nov 2016

Novel Magnetic Nanostructures For Enhanced Magnetic Hyperthermia Cancer Therapy, Zohreh Nemati Porshokouh

USF Tampa Graduate Theses and Dissertations

In this dissertation, I present the results of a systematic study on novel multifunctional nanostructure systems for magnetic hyperthermia applications. All the samples have been synthesized, structurally/magnetically characterized, and tested for magnetic hyperthermia treatment at the Functional Materials Laboratory of the University South Florida. This work includes studies on four different systems: (i) Core/shell Fe/γ-Fe2O3 nanoparticles; (ii) Spherical and cubic exchange coupled FeO/Fe3O4 nanoparticles; (iii) Fe3O4 nano-octopods with different sizes; (iv) High aspect ratio FeCo nanowires and Fe3O4 nanorods.

In particular, we demonstrated the enhancement of the heating …


Material Selection Shape Factors For Compliant Arrays In Bending, David T. Fullwood, Todd G. Nelson, Jared T. Bruton, Nathan E. Rieske, M. Patrick Walton, Larry L. Howell Nov 2016

Material Selection Shape Factors For Compliant Arrays In Bending, David T. Fullwood, Todd G. Nelson, Jared T. Bruton, Nathan E. Rieske, M. Patrick Walton, Larry L. Howell

Faculty Publications

Similar to the general class of metamaterials, compliant arrays (CAs) are engineered from an array of subelements that combine to produce a response that is typically not available from a at panel made of a single material. As such, analysis and design of CA systems requires the integration of both the material and geometrical properties of the array. This paper proposes a convenient and efficient method of combining these essential elements using analytically derived shape factors for bending modes. The approach is validated experimentally, and used to demonstrate large regions of previously inaccessible property combinations in material selection charts that …


Searching Neuroimaging Biomarkers In Mental Disorders With Graph And Multimodal Fusion Analysis Of Functional Connectivity, Hao He Nov 2016

Searching Neuroimaging Biomarkers In Mental Disorders With Graph And Multimodal Fusion Analysis Of Functional Connectivity, Hao He

Electrical and Computer Engineering ETDs

Mental disorders such as schizophrenia (SZ), bipolar (BD), and major depression disorders (MDD) can cause severe symptoms and life disruption. They share some symptoms, which can pose a major clinical challenge to their differentiation. Objective biomarkers based on neuroimaging may help to improve diagnostic accuracy and facilitate optimal treatment for patients. Over the last decades, non-invasive in-vivo neuroimaging techniques such as magnetic resonance imaging (MRI) have been increasingly applied to measure structure and function in human brains. With functional MRI (fMRI) or structural MRI (sMRI), studies have identified neurophysiological deficits in patients’ brain from different perspective. Functional connectivity (FC) analysis …


Development Of In Vivo Systems For Detecting And Studying Ribosome Inhibition By Small Molecules, Shijie Huang Nov 2016

Development Of In Vivo Systems For Detecting And Studying Ribosome Inhibition By Small Molecules, Shijie Huang

Chemistry and Chemical Biology ETDs

The ribosome is the quintessential antibacterial drug target, with many structurally and mechanistically distinct classes of antibacterial agents acting by inhibiting ribosome function. Detecting and quantifying ribosome inhibition by small molecules and investigating their binding modes and mechanisms of action are critical to antibacterial drug discovery and development efforts. To develop a ribosome inhibition assay that is operationally simple, yet provides direct information on the drug target and the mechanism of action, we have developed engineered E. coli strains harboring an orthogonal ribosome controlled green fluorescent protein reporter that produce fluorescent signal when the O-ribosome is inhibited. As a proof …


Fokker-Planck-Based Acceleration For Sn Equations With Highly Forward Peaked Scattering In Slab Geometry, Japan K. Patel Nov 2016

Fokker-Planck-Based Acceleration For Sn Equations With Highly Forward Peaked Scattering In Slab Geometry, Japan K. Patel

Nuclear Engineering ETDs

Short mean free paths are characteristic of charged particles. High energy charged particles often have highly forward peaked scattering cross sections. Transport problems involving such charged particles are also highly optically thick. When problems simultaneously have forward peaked scattering and high optical thickness, their solution, using standard iterative methods, becomes very inefficient. In this dissertation, we explore Fokker-Planck-based acceleration for solving such problems.


Advanced Stochastic Collocation Methods For Polynomial Chaos In Raven, Paul W. Talbot Nov 2016

Advanced Stochastic Collocation Methods For Polynomial Chaos In Raven, Paul W. Talbot

Nuclear Engineering ETDs

As experiment complexity in fields such as nuclear engineering continually increases, so does the demand for robust computational methods to simulate them. In many simulations, input design parameters and intrinsic experiment properties are sources of uncertainty. Often small perturbations in uncertain parameters have significant impact on the experiment outcome. For instance, in nuclear fuel performance, small changes in fuel thermal conductivity can greatly affect maximum stress on the surrounding cladding. The difficulty quantifying input uncertainty impact in such systems has grown with the complexity of numerical models. Traditionally, uncertainty quantification has been approached using random sampling methods like Monte Carlo. …


Approaches For Capturing Time-Varying Functional Network Connectivity With Application To Normative Development And Mental Illness, Barnaly Rashid Nov 2016

Approaches For Capturing Time-Varying Functional Network Connectivity With Application To Normative Development And Mental Illness, Barnaly Rashid

Electrical and Computer Engineering ETDs

Since the beginning of medical science, the human brain has remained an unsolved puzzle; an illusive organ that controls everything- from breathing to heartbeats, from emotion to anger, and more. With the power of advanced neuroimaging techniques, scientists have now started to solve this nearly impossible puzzle, piece by piece. Over the past decade, various in vivo techniques, including functional magnetic resonance imaging (fMRI), have been increasingly used to understand brain functions. fMRI is extensively being used to facilitate the identification of various neuropsychological disorders such as schizophrenia (SZ), bipolar disorder (BP) and autism spectrum disorder (ASD). These disorders are …


Optimized Sizing And Placing Of Distributed Energy Resources (Ders) In An Island Microgrid Using Der-Cam, Bhuwan B. Bastola Nov 2016

Optimized Sizing And Placing Of Distributed Energy Resources (Ders) In An Island Microgrid Using Der-Cam, Bhuwan B. Bastola

Electrical and Computer Engineering ETDs

The electric grid at La Gomera, an island in the Canary archipelago, has been the subject of interest in optimized integration of Distributed Energy Resources (DERs) primarily because of high distribution losses and concerns about complying with emission regulations. Consequently, the utility that operates the island power system wishes to mitigate the problem with installation of renewable and distributed energy sources like PV and battery, which is the focus of this research.

Specifically, the focus of this thesis is to use Distributed Energy Resource - Customer Adoption Model (DER-CAM) to optimize the installation of PV and battery in terms of …


Strongly Enhanced And Directionally Tunable Second-Harmonic Radiation From A Plasmonic Particle-In-Cavity Nanoantenna, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha, Yat Hei Lo, Ming Fang, Weng Cho Chew, Wallace C.H. Choy Nov 2016

Strongly Enhanced And Directionally Tunable Second-Harmonic Radiation From A Plasmonic Particle-In-Cavity Nanoantenna, Xiaoyan Y.Z. Xiong, Li (Lijun) Jun Jiang, Wei E.I. Sha, Yat Hei Lo, Ming Fang, Weng Cho Chew, Wallace C.H. Choy

Electrical and Computer Engineering Faculty Research & Creative Works

Second-harmonic (SH) generation is tremendously important for nonlinear sensing, microscopy, and communication systems. One of the great challenges of current designs is to enhance the SH signal and simultaneously tune its radiation direction with a high directivity. In contrast to the linear plasmonic scattering dominated by a bulk dipolar mode, a complex surface-induced multipolar source at the doubled frequency sets a fundamental limit to control the SH radiation from metallic nanostructures. In this work, we harness a plasmonic hybridization mechanism together with a special selection rule governing the SH radiation to achieve the high-intensity and tunable-direction emission by a metallic …


A Dual Band 450lte/Gsm900 Pifa For Portable Devices, Abraham Loutridis, Kansheng Yang, Matthias John, Max Ammann Nov 2016

A Dual Band 450lte/Gsm900 Pifa For Portable Devices, Abraham Loutridis, Kansheng Yang, Matthias John, Max Ammann

Conference Papers

A dual band PIFA antenna for portable devices is presented. It operates in the 450 LTE (449 − 461 MHz) and GSM 900 (876 – 922 MHz) frequency bands. The proposed antenna which has a very compact size of 7 (0.01λ0) × 7 × 70 (0.1λ0) mm3 and is suitable to integrate in small envelopes, consists of two branches and a metallic patch. The low cost and easily fabricated antenna offers high total efficiency and gain in both bands. Measured and simulated results are provided.


Development Of An Anaerobic-Phototrophic Bioreactor System For Wastewater Treatment, Onur Yilmaz Ozcan Nov 2016

Development Of An Anaerobic-Phototrophic Bioreactor System For Wastewater Treatment, Onur Yilmaz Ozcan

USF Tampa Graduate Theses and Dissertations

For decades, mainstream domestic wastewater treatment has relied on activated sludge processes to remove organic matter, and on biological nutrient removal systems like the A2/O process to remove nutrients. Recently, membrane filtration was also added to the realm of possible technologies for domestic wastewater treatment, with aerobic membrane bioreactors (MBRs) becoming increasingly popular, especially for decentralized, and small to medium scale applications. However, the aerobic activated sludge and MBR processes, which are often combined with biological nutrient removal processes, have high energy costs associated with supplying oxygen to the process, and end up converting the organic matter into …


Mesh Addition Based On The Depth Image (Mabdi), Lucas E. Chavez Nov 2016

Mesh Addition Based On The Depth Image (Mabdi), Lucas E. Chavez

Mechanical Engineering ETDs

Many robotic applications utilize a detailed map of the world and the algorithm used to produce such a map must take into consideration real-world constraints such as computational and memory costs. Traditional mesh-based environmental mapping algorithms receive data from the sensor, create a mesh surface from the data, and then append the surface to a growing global mesh. These algorithms do not provide a computationally efficient mechanism for reducing redundancies in the global mesh. MABDI is able to leverage the knowledge contained in the global mesh to find the difference between what we expect our sensor to see and what …


Electrochemical Fabrication Of Energetic Thin Films, Jonathan J. Coleman Nov 2016

Electrochemical Fabrication Of Energetic Thin Films, Jonathan J. Coleman

Chemical and Biological Engineering ETDs

Current thermal battery heat sources suffer from slow reaction propagation rates and require extreme care when handling to protect from inadvertent ignition sources. Nanostructured intermetallic heat sources are strong candidates for improved heat sources as they have high enthalpy of reaction, are highly conductive before and after firing and are completely gasless reactions. Current fabrication methods of these heat sources rely on a PVD multistep layering process that is time and capital intensive, and cost prohibiting to their use. The composition and nanostructuring these films require can be provided with electrochemical codeposition, where the two components (aluminum and nickel) are …


Experimental Investigation Of Plasma Dynamics In Jets And Bubbles Using A Compact Coaxial Plasma Gun In A Background Magnetized Plasma, Yue Zhang Nov 2016

Experimental Investigation Of Plasma Dynamics In Jets And Bubbles Using A Compact Coaxial Plasma Gun In A Background Magnetized Plasma, Yue Zhang

Electrical and Computer Engineering ETDs

Numerous solar and astrophysical observations of jet- and bubble-like plasma structures exhibit morphological similarities, suggesting that there may be common plasma physics at work in the formation and evolution processes of these structures at different system scales. The ideal magnetohydrodynamics (MHD) provide the necessary theoretical basis for employing laboratory experiments to investigate key physical processes in nonlinear astrophysical and solar systems, especially when magnetic fields are present.

A coaxial magnetized plasma gun has been designed, installed, and operated in the HelCat linear device at the University of New Mexico. In Region I, a current-driven plasma jet is formed. The plasma …


Using Timing-Based Side Channels For Anomaly Detection In Industrial Control Systems, Stephen Dunlap, Jonathan W. Butts, Juan L. Lopez Jr., Mason J. Rice, Barry E. Mullins Nov 2016

Using Timing-Based Side Channels For Anomaly Detection In Industrial Control Systems, Stephen Dunlap, Jonathan W. Butts, Juan L. Lopez Jr., Mason J. Rice, Barry E. Mullins

Faculty Publications

The critical infrastructure, which includes the electric power grid, railroads and water treatment facilities, is dependent on the proper operation of industrial control systems. However, malware such as Stuxnet has demonstrated the ability to alter industrial control system parameters to create physical effects. Of particular concern is malware that targets embedded devices that monitor and control system functionality, while masking the actions from plant operators and security analysts. Indeed, system security relies on guarantees that the assurance of these devices can be maintained throughout their lifetimes. This paper presents a novel approach that uses timing-based side channel analysis to establish …


New Approaches For Estimating Hemispheric Lateralization From Resting State Fmri Data With Relationship To Age, Gender And Mental Disorders, Oktay Agcaoglu Nov 2016

New Approaches For Estimating Hemispheric Lateralization From Resting State Fmri Data With Relationship To Age, Gender And Mental Disorders, Oktay Agcaoglu

Electrical and Computer Engineering ETDs

Lateralization is specialization of the brain hemispheres in certain tasks, such as language, mathematics, cognition and motor skills. It is one of the most queried topics related to the human brain. After the invention of modern medical imaging techniques including functional magnetic resonance imaging (fMRI), scientific research about the human brain, including lateralization, gained huge momentum. There have been a remarkable numbers of studies about lateralization and most of these studies focused on investigating which part of the brain dominates in which tasks. However, there have been very few lateralization studies on brain intrinsic activity, i.e., resting state activity where …


Finite Element Simulation Of Pzt-Aided Interrogation Of Composite Laminates Exhibiting Damage, Amany Micheal, Yehia Bahei-El-Din Nov 2016

Finite Element Simulation Of Pzt-Aided Interrogation Of Composite Laminates Exhibiting Damage, Amany Micheal, Yehia Bahei-El-Din

Centre for Advanced Materials

Piezoelectricity has proved effective in capturing changes in structures caused by various damage mechanisms. In one approach, piezoelectric wafer active sensors (PWAS) are mounted on the surface of the host structure and utilized as both actuators and sensors to interrogate the structure and monitor its health. This is achieved by subjecting the PWAS to a transient electric pulse and reading the resulting voltage. Changes in the stiffness of the substrate due to structural damage affect the response of the PWAS, which could be correlated to integrity of the structure. Applying this technique to fibrous composite laminates encounters particular challenges due …


Teaching Consolidation: Case Study Of Preloading With Vertical Drains, Robb Moss, Judd King, Gregg Fiegel Nov 2016

Teaching Consolidation: Case Study Of Preloading With Vertical Drains, Robb Moss, Judd King, Gregg Fiegel

Civil and Environmental Engineering

This paper describes a ground improvement case study where preloading and prefabricated vertical drains (PVDs) were used to accelerate foundation settlements. The case study is used in a classroom setting with the learning objective of introducing engineering students to methods for estimating settlement of shallow foundations on compressible soils. The project site was developed for a corporate retail chain planning to open a new facility in San Luis Obispo, California. Up to 2.5 meters of fill were needed across much of the site to raise foundations and improvements above the flood elevation. Loads from the fill and the structure were …


Characteristics And Products Of The Reductive Degradation Of 3-Nitro-1,2,4-Triazol-5-One (Nto) And 2,4-Dinitroanisole (Dnan) In A Fe-Cu Bimetal System, Elsie Kitcher, Washington Braida, Agamemnon Koutsospyros, Julius Pavlov, Tsang-Liang Su Nov 2016

Characteristics And Products Of The Reductive Degradation Of 3-Nitro-1,2,4-Triazol-5-One (Nto) And 2,4-Dinitroanisole (Dnan) In A Fe-Cu Bimetal System, Elsie Kitcher, Washington Braida, Agamemnon Koutsospyros, Julius Pavlov, Tsang-Liang Su

Civil Engineering Faculty Publications

It has been shown previously that, under acidic conditions, 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4-dinitroanisole (DNAN) degrade in the presence of iron/copper bimetal particles; the reactions can be modeled by pseudo-first-order kinetics. This study investigates the reaction mechanisms of the degradation processes under different conditions. Batch studies were conducted using laboratory-prepared solutions and an industrial insensitive munition-laden (IMX) wastewater. The influence of parameters such as initial pH of the solution, copper/iron (Fe-Cu) contact, and solid/liquid ratio were systematically investigated to assess their impact on the reaction kinetics. These parameters were subsequently incorporated into pseudo-first-order decomposition models for NTO and DNAN. The activation …


Towards Learning And Verifying Invariants Of Cyber-Physical Systems By Code Mutation, Yuqi Chen, Christopher M. Poskitt, Jun Sun Nov 2016

Towards Learning And Verifying Invariants Of Cyber-Physical Systems By Code Mutation, Yuqi Chen, Christopher M. Poskitt, Jun Sun

Research Collection School Of Computing and Information Systems

Cyber-physical systems (CPS), which integrate algorithmic control with physical processes, often consist of physically distributed components communicating over a network. A malfunctioning or compromised component in such a CPS can lead to costly consequences, especially in the context of public infrastructure. In this short paper, we argue for the importance of constructing invariants (or models) of the physical behaviour exhibited by CPS, motivated by their applications to the control, monitoring, and attestation of components. To achieve this despite the inherent complexity of CPS, we propose a new technique for learning invariants that combines machine learning with ideas from mutation testing. …


Scalable Dashboard For Identifying Split Failures And Heuristic For Reallocating Split Times, Howell Li, Lucy Richardson, Christopher M. Day, James Howard, Darcy M. Bullock Nov 2016

Scalable Dashboard For Identifying Split Failures And Heuristic For Reallocating Split Times, Howell Li, Lucy Richardson, Christopher M. Day, James Howard, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

The three fundamental parameters of a traffic signal system are split, cycle, and offset. This paper describes the use of high-resolution data (a) to identify time periods during which split parameters may be insufficient and (b) to help practitioners identify opportunities for reallocating split time. A case study of seven corridors with 47 intersections is presented. A drill-down approach was developed to identify movements that could be improved by a reallocation of split times. A heuristic that can reallocate up to 5 seconds of underutilized green time on a competing phase was applied to those corridors. …