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System Of Systems (Sos) Architecture For Digital Manufacturing Cybersecurity, Lirim Ashiku, Cihan H. Dagli Aug 2019

System Of Systems (Sos) Architecture For Digital Manufacturing Cybersecurity, Lirim Ashiku, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Technology advancements of real time connectivity and computing powers has evolved the way people manage activities triggering heavy reliance on smart devices. This has reshaped the ability to memorize crucial information, instead accumulate the information into devices allowing real-time fingertip access when needed. Inability to access such information when needed is routinely assumed with device malfunctioning bypassing the probability of compromise, but what if the information is now being accessed by adversaries depriving the data-owner access to crucial information? Cyber manufacturing systems are not immune from these issues. It is possible to approach this problem as generating SoS meta-architecture. In …

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Bioactive Glass Fiber Fabrication Via A Combination Of Sol-Gel Process With Electro-Spinning Technique, Malvika Nagrath, Adel Alhalawani, Alireza Rahimnejad Yazdi, Mark R. Towler Aug 2019

Bioactive Glass Fiber Fabrication Via A Combination Of Sol-Gel Process With Electro-Spinning Technique, Malvika Nagrath, Adel Alhalawani, Alireza Rahimnejad Yazdi, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

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Transportation Planning For Automated Vehicles -- Or Automated Vehicles For Transportation Planning?, Shane Ray Epting Aug 2019

Transportation Planning For Automated Vehicles -- Or Automated Vehicles For Transportation Planning?, Shane Ray Epting

Arts, Languages and Philosophy Faculty Research & Creative Works

In recent years, philosophical examinations of automated vehicles have progressed far beyond initial concerns over the ethical decisions that pertain to programming in the event of a crash. In turn, this paper moves in that direction, focusing on the motivations behind efforts to implement driverless vehicles into urban settings. The author argues that the many perceived benefits of these technologies yield a received view of automated vehicles. This position holds that driverless vehicles can solve most if not all urban mobility issues. However, the problem with such an outlook is that it lends itself to transportation planning for automated vehicles, …

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Generalizing Multiple Access Wiretap And Wiretap Ii Channel Models: Achievable Rates And Cost Of Strong Secrecy, Mohamed Nafea, Aylin Yener Aug 2019

Generalizing Multiple Access Wiretap And Wiretap Ii Channel Models: Achievable Rates And Cost Of Strong Secrecy, Mohamed Nafea, Aylin Yener

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, new two-user multiple access wiretap channel models are studied. First, the multiple access wiretap channel II with a discrete memoryless main channel under different wiretapping scenarios is introduced. The wiretapper, as in the classical wiretap channel II model, chooses a fixed-size subset of the channel uses, in which it obtains noise-free observations of one of the codewords: a deterministic function, e.g., superposition, of the two codewords or each of the two codewords. A fourth wiretapping scenario is considered, in which the wiretapper, in each position it chooses, decides to observe either one of the codewords or both …

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A Region-Based Deep Learning Algorithm For Detecting And Tracking Objects In Manufacturing Plants, Muhammad Monjurul Karim, David Doell, Ravon Lingard, Zhaozheng Yin, Ming-Chuan Leu, Ruwen Qin Aug 2019

A Region-Based Deep Learning Algorithm For Detecting And Tracking Objects In Manufacturing Plants, Muhammad Monjurul Karim, David Doell, Ravon Lingard, Zhaozheng Yin, Ming-Chuan Leu, Ruwen Qin

Computer Science Faculty Research & Creative Works

In today's competitive production era, the ability to identify and track important objects in a near real-time manner is greatly desired among manufacturers who are moving towards the streamline production. Manually keeping track of every object in a complex manufacturing plant is infeasible; therefore, an automatic system of that functionality is greatly in need. This study was motivated to develop a Mask Region-based Convolutional Neural Network (Mask RCNN) model to semantically segment objects and important zones in manufacturing plants. The Mask RCNN was trained through transfer learning that used a neural network (NN) pre-trained with the MS-COCO dataset as the …

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Probing Surface Characteristics Of Rare Earth Minerals Using Contact Angle Measurements, Atomic Force Microscopy, And Inverse Gas Chromatography, Mostafa Khodakarami, Lana Z. Alagha, Daniel J. Burnett Aug 2019

Probing Surface Characteristics Of Rare Earth Minerals Using Contact Angle Measurements, Atomic Force Microscopy, And Inverse Gas Chromatography, Mostafa Khodakarami, Lana Z. Alagha, Daniel J. Burnett

Mining Engineering Faculty Research & Creative Works

Rare earth minerals (REMs) such as bastnaesite, monazite, and xenotime are of considerable significance since they are the main commercial sources for rare earth elements (REEs) with cutting-edge applications. Fundamental understanding of surface properties of REMs is essential to identify the reactions taking place at different interfaces to develop more robust technologies for the recovery of REEs. The goal of this study is to provide a comprehensive investigation on the surface energy characteristics of bastnaesite and xenotime, as the primary sources of light and heavy rare earth elements, respectively. Crystal's orientation of REMs was identified using surface X-ray diffraction analysis, …

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Computational Fluid Dynamic Simulation Of Inhaled Radon Dilution By Auxiliary Ventilation In A Stone-Coal Mine Laneway And Dosage Assessment Of Miners, Bin Zhou, Ping Chang, Guang Xu Aug 2019

Computational Fluid Dynamic Simulation Of Inhaled Radon Dilution By Auxiliary Ventilation In A Stone-Coal Mine Laneway And Dosage Assessment Of Miners, Bin Zhou, Ping Chang, Guang Xu

Mining Engineering Faculty Research & Creative Works

Inhaled radon status in the laneways of some Chinese stone-coal mines is a cause of concern. In this study, computational fluid dynamics simulations were employed to investigate three flowrates of the dilution gas (2.5, 5, and 7.5 m3/s) and radon distributions at realistic breathing levels (1.6, 1.75, and 1.9 m). The results showed that there are obvious jet-flow, backflow, and vortex zones near the heading face, and a circulation flow at the rear of the laneway. A high radon concentration area was found to be caused by the mining machinery. As the ventilation rate increased, the radon concentrations …

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Joint Manufacturing And Onsite Microgrid System Control Using Markov Decision Process And Neural Network Integrated Reinforcement Learning, Wenqing Hu, Zeyi Sun, Y. Zhang, Y. Li Aug 2019

Joint Manufacturing And Onsite Microgrid System Control Using Markov Decision Process And Neural Network Integrated Reinforcement Learning, Wenqing Hu, Zeyi Sun, Y. Zhang, Y. Li

Mathematics and Statistics Faculty Research & Creative Works

Onsite microgrid generation systems with renewable sources are considered a promising complementary energy supply system for manufacturing plant, especially when outage occurs during which the energy supplied from the grid is not available. Compared to the widely recognized benefits in terms of the resilience improvement when it is used as a backup energy system, the operation along with the electricity grid to support the manufacturing operations in non-emergent mode has been less investigated. In this paper, we propose a joint dynamic decision-making model for the optimal control for both manufacturing system and onsite generation system. Markov Decision Process (MDP) is …

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An Analysis Of The Evolving Intellectual Structure Of Health Information Systems Research In The Information Systems Discipline, Langtao Chen, Aaron Baird, Detmar W. Straub Aug 2019

An Analysis Of The Evolving Intellectual Structure Of Health Information Systems Research In The Information Systems Discipline, Langtao Chen, Aaron Baird, Detmar W. Straub

Business and Information Technology Faculty Research & Creative Works

The rapid evolution of health information systems (Health IS) research has led to many significant contributions. However, while the Health IS subset of information systems (IS) scholarship has considerably grown over the past two decades, this growth has led to questions regarding the current intellectual structure of this area of inquiry. In an effort to more fully understand how Health IS research has contributed to the IS discipline, and what this may mean for future Health IS research in the IS domain, we conduct an in-depth evaluation of Health IS research published in mainstream IS journals. We apply citation analysis, …

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Machine Learning Methodology Review For Computational Electromagnetics, He Ming Yao, Lijun Jiang, Huan Huan Zhang, Wei E.I. Sha Aug 2019

Machine Learning Methodology Review For Computational Electromagnetics, He Ming Yao, Lijun Jiang, Huan Huan Zhang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

While machine learning is revolutionizing every corner of modern technologies, we have been attempting to explore whether machine learning methods could be used in computational electromagnetic (CEM). In this paper, five efforts in line with this direction are reviewed. They include forward methods such as the method of moments (MoM) solved by the artificial neural network training process, FDTD PML (perfectly matched layer) using the hyperbolic tangent basis function (HTBF), etc. There are also inverse problems that use the deep ConvNets for the effective source reconstruction and subwavelength imaging in the far-field. Benchmarks are provided to demonstrate the feasibility of …

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People's Self-Reported Encounters Of Perceiving Mind In Artificial Intelligence, Daniel Burton Shank, Alexander Gott Aug 2019

People's Self-Reported Encounters Of Perceiving Mind In Artificial Intelligence, Daniel Burton Shank, Alexander Gott

Psychological Science Faculty Research & Creative Works

This article presents the data from two surveys that asked about everyday encounters with artificial intelligence (AI) systems that are perceived to have attributes of mind. In response to specific attribute prompts about an AI, the participants qualitatively described a personally-known encounter with an AI. In survey 1 the prompts asked about an AI planning, having memory, controlling resources, or doing something surprising. In survey 2 the prompts asked about an AI experiencing emotion, expressing desires or beliefs, having human-like physical features, or being mistaken for a human. The original responses were culled based on the ratings of multiple coders …

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Computational Study Of The Ro-Vibrational Spectrum Of Co-Co₂, Eduardo Castro-Juarez, Xiao-Gang Wang, Tucker Carrington Jr., Ernesto Quintas-Sánchez, Richard Dawes Aug 2019

Computational Study Of The Ro-Vibrational Spectrum Of Co-Co₂, Eduardo Castro-Juarez, Xiao-Gang Wang, Tucker Carrington Jr., Ernesto Quintas-Sánchez, Richard Dawes

Chemistry Faculty Research & Creative Works

An accurate ab initio ground-state intermolecular potential energy surface (PES) was determined for the CO-CO2 van der Waals dimer. The Lanczos algorithm was used to compute rovibrational energies on this PES. For both the C-in and O-in T-shaped isomers, the fundamental transition frequencies agree well with previous experimental results. We confirm that the in-plane states previously observed are geared states. In addition, we have computed and assigned many other vibrational states. The rotational constants we determine from J = 1 energy levels agree well with their experimental counterparts. Planar and out-of-plane cuts of some of the wavefunctions we compute …

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Enhanced Flocculation Using Drinking Water Treatment Plant Sedimentation Residual Solids, Sandhya Rao Poleneni, Enos Inniss, Honglan Shi, John Yang, Bin Hua, Joseph Clamp Aug 2019

Enhanced Flocculation Using Drinking Water Treatment Plant Sedimentation Residual Solids, Sandhya Rao Poleneni, Enos Inniss, Honglan Shi, John Yang, Bin Hua, Joseph Clamp

Chemistry Faculty Research & Creative Works

Inefficient removal of total organic carbon (TOC) leads to the formation of carcinogenic disinfection by-products (DBPs) when a disinfectant is added. This study is performed in an effort to develop a simple, non-invasive, and cost-effective technology that will effectively lower organic precursors by having water utilities reuse their treatment residual solids. Jar tests are used to simulate drinking water treatment processes with coagulants-aluminum sulfate (alum), poly-aluminum chloride (PACl), and ferric chloride and their residual solids. Ten coagulant-to-residual (C/R) ratios are tested with water from the Missouri River at Coopers Landing in Columbia, MO versus alluvial ground waters. This treatment results …

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Strategic Gift Giving In Vendor Relationships: The Gift Of Cognitive Regard, Cecil Eng Huang Chua, Cheng Chen, Ji-Ye Mao Aug 2019

Strategic Gift Giving In Vendor Relationships: The Gift Of Cognitive Regard, Cecil Eng Huang Chua, Cheng Chen, Ji-Ye Mao

Business and Information Technology Faculty Research & Creative Works

Increasing competition in the IT vendor landscape means it is increasingly difficult for vendors to sustain themselves by competing on price. Thus, many vendors desire to become strategic partners with their clients to thereby acquire a secure monopoly-like position on IT services. How should vendors do so? We argue one way is via the strategic distribution of gifts. This research unpacks one particularly effective gift type- the gift of cognitive regard through a qualitative analysis of a client-vendor relationship. This gift type has five properties: (1) Known Effortfulness, (2) Deep cognitive understanding, (3) Inalienability, (4) Nontransferrability, and (5) Contract temporality …

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A Displacement Controlled Fatigue Test Method For Additively Manufactured Materials, Mohammad Masud Parvez, Yitao Chen, Sreekar Karnati, Connor Coward, Joseph William Newkirk, Frank W. Liou Aug 2019

A Displacement Controlled Fatigue Test Method For Additively Manufactured Materials, Mohammad Masud Parvez, Yitao Chen, Sreekar Karnati, Connor Coward, Joseph William Newkirk, Frank W. Liou

Materials Science and Engineering Faculty Research & Creative Works

A novel adaptive displacement-controlled test setup was developed for fatigue testing on mini specimens. In property characterization of additive manufacturing materials, mini specimens are preferred due to the specimen preparation, and manufacturing cost but mini specimens demonstrate higher fatigue strength than standard specimens due to the lower probability of material defects resulting in fatigue. In this study, a dual gauge section Krouse type mini specimen was designed to conduct fatigue tests on additively manufactured materials. The large surface area of the specimen with a constant stress distribution and increased control volume as the gauge section may capture all different types …

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A Framework Of Integrating Manufacturing Plants In Smart Grid Operation: Manufacturing Flexible Load Identification, Md. Monirul Islam, Zeyi Sun, Wenqing Hu, Cihan H. Dagli Aug 2019

A Framework Of Integrating Manufacturing Plants In Smart Grid Operation: Manufacturing Flexible Load Identification, Md. Monirul Islam, Zeyi Sun, Wenqing Hu, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

In the deregulated electricity markets run by Independent System Operator (ISO), a two-settlement (day-ahead and real-time) process is typically used to determine the electricity price to the end-use customers at different buses. In the day-ahead settlement, the demand is predicted at each bus based on the previous consumption behavior of the consumers and thus, Locational Marginal Price (LMP) can be determined and shared to the consumers. A significant gap is usually observed between the planned and real-time demands due to the uncertainties of the weather (temperature, wind-speed etc.), the intensity of business, and everyday activities. Therefore, a large price variation …

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Infrared Glass–Ceramics With Multidispersion And Gradient Refractive Index Attributes, Laura Sisken, Myungkoo Kang, Johann M. Veras, Charmayne Lonergan, Andrew Buff, Anupama Yadav, Devon Mcclane, Cesar Blanco, Clara Rivero-Baleine, Theresa S. Mayer, Kathleen A. Richardson Aug 2019

Infrared Glass–Ceramics With Multidispersion And Gradient Refractive Index Attributes, Laura Sisken, Myungkoo Kang, Johann M. Veras, Charmayne Lonergan, Andrew Buff, Anupama Yadav, Devon Mcclane, Cesar Blanco, Clara Rivero-Baleine, Theresa S. Mayer, Kathleen A. Richardson

Materials Science and Engineering Faculty Research & Creative Works

Infrared (IR) glass–ceramics (GCs) hold the potential to dramatically expand the range of optical material solutions available for use in bulk and planar optical systems in the IR. Current material solutions are limited to single- or polycrystalline materials and traditional IR-transparent optical glasses. GCs that can be processed with spatial control and extent of induced crystallization present the opportunity to realize an effective refractive index variation, enabling arbitrary gradient refractive index elements with tailored optical function. This work discusses the role of the parent glass composition and morphology on nanocrystal phase formation in a multicomponent chalcogenide glass. Through a two-step …

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Ionic Conductivity Behavior By Activated Hopping Conductivity (Ahc) Of Barium Aluminoborosilicate Glass–Ceramic System Designed For Sofc Sealing, M. J. Da Silva, W. M. Pontuschka, J. F. Bartolomé, P. Jasinski, J. Karczewski, Signo Tadeu Dos Reis Aug 2019

Ionic Conductivity Behavior By Activated Hopping Conductivity (Ahc) Of Barium Aluminoborosilicate Glass–Ceramic System Designed For Sofc Sealing, M. J. Da Silva, W. M. Pontuschka, J. F. Bartolomé, P. Jasinski, J. Karczewski, Signo Tadeu Dos Reis

Materials Science and Engineering Faculty Research & Creative Works

Non-conducting BaO-B2O3 -Al2O3 -SiO2 parent glasses designed for solid oxide fuel cell (SOFC) sealing applications were prepared using the melt-quenching technique. The glass formation region was determined according to phase equilibrium relations and was found to be in the composition range 70BaO-(x) Al2O3 -(10−x) B2O3 -20SiO2 where 3.0 < x < 6.0 wt.%. The conductivity values obtained conductivity ranged from 10 −5 to 10 −10 S/cm at temperatures between 600 and 850 °C. The batch compositions presented a threshold of dc conductivity near 70BaO wt% with a quasi linear behavior with the decrease of the BaO content. Different values of conduction activation energy were observed at temperatures above the glass transition temperature (T g ) (up to 700 °C), which were attributed to the thermal bond-breaking of non-bridging oxygen (NBO) defects. The experimental results of the electrochemical characterization by impedance spectroscopy of glass–ceramic interfaces with yttria-stabilized zirconia (YSZ) acting as solid ionic conductor electrolyte are presented and discussed.

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Detection Of Sensor Attacks In Uncertain Stochastic Linear Systems, Chandreyee Bhowmick, S. Jagannathan Aug 2019

Detection Of Sensor Attacks In Uncertain Stochastic Linear Systems, Chandreyee Bhowmick, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel attack detection scheme is developed for linear discrete-time systems with unknown dynamics that are subject to the additive process and output measurements noise. A novel stochastic adaptive observer is proposed to estimate the state vector in the presence of noisy sensor measurements and uncertain dynamics, and also to generate the innovation signal to detect attacks using a modified $\chi2} $ detector. It has been shown that the innovation signal, which is defined as the difference between the measured and the estimated output from the observer, has a Gaussian distribution with non-zero mean. The modified $\chi^ {2} $ detector …

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Neutrino Splitting For Lorentz-Violating Neutrinos: Detailed Analysis, G. Somogyi, I. Nandori, Ulrich D. Jentschura Aug 2019

Neutrino Splitting For Lorentz-Violating Neutrinos: Detailed Analysis, G. Somogyi, I. Nandori, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

Lorentz-violating neutrino parameters have been severely constrained on the basis of astrophysical considerations. In the high-energy limit, one generally assumes a superluminal dispersion relation of an incoming neutrino of the form E≈ |p ⃗|v , where E is the energy, p ⃗ is the momentum and v ₌ √(1+ δ) > 1. Lepton-pair creation due to a Cerenkov-radiation-like process (ν → ν + е-+e+) becomes possible above a certain energy threshold, and bounds on the Lorentz-violating parameter δ can be derived. Here, we investigate a related process, νi→ νi+ νf+ …

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Fabrication And Characterization Of Alₓcrcufeni₂ High-Entropy Alloys Coatings By Laser Metal Deposition, Wenyuan Cui, Xinchang Zhang, Lan Li, Yitao Chen, Tan Pan, Frank W. Liou Aug 2019

Fabrication And Characterization Of Alₓcrcufeni₂ High-Entropy Alloys Coatings By Laser Metal Deposition, Wenyuan Cui, Xinchang Zhang, Lan Li, Yitao Chen, Tan Pan, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

High-entropy alloys (HEAs) are becoming new hot spots in the metallic materials community, which are defined to contain equiatomic or close-to-equiatomic compositions. HEAs can possess many interesting mechanical properties, and in particular, they have the great potential to be used as coating materials requiring high hardness and wear resistance. In this study, the feasibility of fabrication AlₓCrCuFeNi₂ (x=0,0.75) HEAs was investigated via laser metal deposition from elemental powders. The microstructure, phase structure, and hardness were studied by an optical microscope, scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS), electron backscatter diffraction (EBSD) and Vickers hardness tester. The bonding between the …

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Predictive Model For Thermal And Stress Field In Selective Laser Melting Process -- Part Ii, Lan Li, Lei Yan, Yitao Chen, Tan Pan, Xinchang Zhang, Wenyuan Cui, Aaron Flood, Frank W. Liou Aug 2019

Predictive Model For Thermal And Stress Field In Selective Laser Melting Process -- Part Ii, Lan Li, Lei Yan, Yitao Chen, Tan Pan, Xinchang Zhang, Wenyuan Cui, Aaron Flood, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Finite Element Analysis (FEA) is used to predict the transient thermal cycle and optimize process parameters to analyze these effects on deformation and residual stresses. However, the process of predicting the thermal history in this process with the FEA method is usually time-consuming, especially for large-scale parts. In this paper, an effective predictive model of part deformation and residual stress was developed for accurately predicting deformation and residual stresses in large-scale parts. An equivalent body heat flux proposed from the single layer laser scan model was imported as the thermal load to the layer by layer model. The hatched layer …

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Action Recognition In Manufacturing Assembly Using Multimodal Sensor Fusion, Md. Al-Amin, Wenjin Tao, David Doell, Ravon Lingard, Zhaozheng Yin, Ming-Chuan Leu, Ruwen Qin Aug 2019

Action Recognition In Manufacturing Assembly Using Multimodal Sensor Fusion, Md. Al-Amin, Wenjin Tao, David Doell, Ravon Lingard, Zhaozheng Yin, Ming-Chuan Leu, Ruwen Qin

Computer Science Faculty Research & Creative Works

Production innovations are occurring faster than ever. Manufacturing workers thus need to frequently learn new methods and skills. In fast changing, largely uncertain production systems, manufacturers with the ability to comprehend workers' behavior and assess their operation performance in near real-time will achieve better performance than peers. Action recognition can serve this purpose. Despite that human action recognition has been an active field of study in machine learning, limited work has been done for recognizing worker actions in performing manufacturing tasks that involve complex, intricate operations. Using data captured by one sensor or a single type of sensor to recognize …

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Chapter 2: 2d/3d Finite Element Spaces, Xiaoming He Aug 2019

Chapter 2: 2d/3d Finite Element Spaces, Xiaoming He

AOER Course Materials

No abstract provided.

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Inverse Design Of Long-Range Intensity Correlation In Scattering Media, M. Koirala, R. Sarma, H. Cao, Alexey Yamilov Aug 2019

Inverse Design Of Long-Range Intensity Correlation In Scattering Media, M. Koirala, R. Sarma, H. Cao, Alexey Yamilov

Physics Faculty Research & Creative Works

We demonstrate a possibility of using geometry to deterministically control nonlocal correlation of waves undergoing mesoscopic transport through a disordered waveguide. In case of nondissipative medium, we find an explicit relationship between correlation and the shape of the system. Inverting this relationship, we realize inverse design: we obtain specific waveguide shape that leads to a predetermined nonlocal correlation. The proposed technique offers an approach to coherent control of wave propagation in random media that is complementary to wave-front shaping.

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Pseudo-Periodic Natural Higgs Inflation, I. G. Marian, N. Defenu, Ulrich D. Jentschura, A. Trombettoni, I. Nandori Aug 2019

Pseudo-Periodic Natural Higgs Inflation, I. G. Marian, N. Defenu, Ulrich D. Jentschura, A. Trombettoni, I. Nandori

Physics Faculty Research & Creative Works

Inflationary cosmology represents a well-studied framework to describe the expansion of space in the early universe, as it explains the origin of the large-scale structure of the cosmos and the isotropy of the cosmic microwave background radiation. The recent detection of the Higgs boson renewed research activities based on the assumption that the inflaton could be identified with the Higgs field. At the same time, the question whether the inflationary potential can be extended to the electroweak scale and whether it should be necessarily chosen ad hoc in order to be physically acceptable are at the center of an intense …

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Radiative Transfer Distortions Of Lyman Α Emitters: A New Fingers-Of-God Damping In The Clustering In Redshift Space, Chris Byrohl, Shun Saito, Christoph Behrens Aug 2019

Radiative Transfer Distortions Of Lyman Α Emitters: A New Fingers-Of-God Damping In The Clustering In Redshift Space, Chris Byrohl, Shun Saito, Christoph Behrens

Physics Faculty Research & Creative Works

Complex radiative transfer (RT) of the Lyman α photons poses a theoretical challenge to galaxy surveys that infer the large-scale structure with Lyman α emitters (LAEs). Guided by RT simulations, prior studies investigated the impact of RT on the large-scale LAE clustering, and claimed that RT induces a selection effect which results in an anisotropic distortion even in real space but in an otherwise negligible effect in redshift space. However, our previous study, which relies on a full RT code run on the Illustris simulations, shows that the anisotropic selection effect was drastically reduced with higher spatial resolution. Adopting the …

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Cyber-Enabled Product Lifecycle Management: A Multi-Agent Framework, Vishwa V. Kumar, Avimanyu Sahoo, Frank W. Liou Aug 2019

Cyber-Enabled Product Lifecycle Management: A Multi-Agent Framework, Vishwa V. Kumar, Avimanyu Sahoo, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Trouble free use of a product and its associated services for a specified minimum period of time is a major factor to win the customer's trust in the product. Rapid and easy serviceability to maintain its functionalities plays a key role in achieving this goal. However, the sustainability of such a model cannot be promised unless the current health status of the product is monitored and condition-based maintenance is exercised. Internet of Things (IoT), an important connectivity paradigm of recent times, which connects physical objects to the internet for real-time information exchange and execution of physical actions via wired/wireless protocols. …

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Predictive Model For Thermal And Stress Field In Selective Laser Melting Process -- Part I, Lan Li, Lei Yan, Wenyuan Cui, Yitao Chen, Tan Pan, Xinchang Zhang, Aaron Flood, Frank W. Liou Aug 2019

Predictive Model For Thermal And Stress Field In Selective Laser Melting Process -- Part I, Lan Li, Lei Yan, Wenyuan Cui, Yitao Chen, Tan Pan, Xinchang Zhang, Aaron Flood, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

During the part forming in laser powder bed fusion process, thermal distortion is one big problem due to the thermal stress which is caused by the high cooling rate and temperature gradient. Therefore, it is important to know the effect of process parameters on thermal and stress evolution in the melt zone. In this paper, a 3D finite element model for Selective Laser Melting (SLM) process based on sequentially coupled thermo-mechanical field analysis was developed for accurately predicting thermal history and surface features, like distortion and residual stress. Temperature dependent material properties for performed material 304L stainless steel are incorporated …

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Attack Detection In Linear Networked Control Systems By Using Learning Methodology, Haifeng Niu, A. Sahoo, C. Bhowmick, S. Jagannathan Aug 2019

Attack Detection In Linear Networked Control Systems By Using Learning Methodology, Haifeng Niu, A. Sahoo, C. Bhowmick, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel learning-based attack detection scheme for linear networked control systems (NCS) is introduced. The class of attacks considered here tends to increase network induced delays and packet losses which affects the physical system dynamics. For the network side, an adaptive observer is proposed to generate the attack detection residual, which in turn is utilized to determine the onset of an attack when it exceeds a predefined threshold. The uncertain stochastic physical system dynamics as a result of network-induced delays of packet losses require an optimal Q-learning based event-triggered controller that optimizes the control policy and the event-triggering instants simultaneously. …

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