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Additive Manufacturing Of Glass Using A Filament Fed Process, Junjie Luo Jan 2017

Additive Manufacturing Of Glass Using A Filament Fed Process, Junjie Luo

Doctoral Dissertations

"There are many scientific and engineering applications of glass including optics, communications, electronics, and hermetic seals, there has been minimal research towards the Additive Manufacturing (AM) of transparent glass parts. The special thermal and optical properties of glasses make them hard to be printed using conventional AM techniques. In this dissertation, two different AM techniques for glass AM were developed, Selective Laser Melting (SLM) and filament fed process.

Semi-transparent parts were printed with SLM process. However, the filament fed process was found to be more robust and promising for printing optically transparent glass parts. Therefore, this dissertation is focused on …


Uface: Your Universal Password No One Can See, Nicholas Steven Hilbert Jan 2017

Uface: Your Universal Password No One Can See, Nicholas Steven Hilbert

Masters Theses

"With the advantage of not having to memorize long passwords, facial authentication has become a topic of interest among researchers. However, since many users store images containing their face on social networking sites, a new challenge emerges in preventing attackers from impersonating these users by using these online photos. Another problem with most current facial authentication protocols is that they require an unencrypted image of each registered user's face to compare against. Moreover, they might require the user's device to execute computationally expensive multiparty protocols which presents a problem for mobile devices with limited processing power. Finally, these authentication protocols …


Cloth-Air Partitioning Of Oxybenzone, Jonathan T. Hill Jan 2017

Cloth-Air Partitioning Of Oxybenzone, Jonathan T. Hill

Masters Theses

"Clothing has been proven to be a significant accumulator of chemicals from the air. Semi-volatile organic compounds (SVOCs) have a high affinity towards textiles, and measuring the equilibrium partition coefficient between cloth and air (Kcloth-air) for SVOCs is crucial in predicting human exposure to these compounds. This study aims to quantify Kcloth-air for oxybenzone to contribute to a larger human exposure experiment carried out at the Technical University of Denmark (DTU). Kcloth-air for oxybenzone was calculated using data collected from the exposure chamber at DTU and from performing extractions of oxybenzone in fabric samples from the …


Well Log Interpretation And 3d Reservoir Property Modeling Of Maui-B Field, Taranaki Basin, New Zealand, Aziz Mennan Jan 2017

Well Log Interpretation And 3d Reservoir Property Modeling Of Maui-B Field, Taranaki Basin, New Zealand, Aziz Mennan

Masters Theses

"Maui-B is one of the largest hydrocarbon-producing fields in the Taranaki Basin. Many previous works have estimated reservoir volume. This study uses 3D property modeling, which is one of the most powerful tools to characterize lithology and reservoir fluids distribution through the field. This modeling will help in understanding the reservoir properties and enhancing the production by selecting the best location for future drilling candidates. In this study, 3D seismic, core, and well log data were used to build and define a structural model, facies analysis, and petrophysical parameters. After well log interpretation and petrophysical parameter calculations, each parameter was …


Faculty Senate Minutes Dec. 14, 2016 (Special Meeting), Missouri University Of Science And Technology Faculty Senate Dec 2016

Faculty Senate Minutes Dec. 14, 2016 (Special Meeting), Missouri University Of Science And Technology Faculty Senate

Minutes & Agendas

No abstract provided.


Computational Modelling For Phase Transformation Prediction In Super-Invar Alloys: Analytical And Experimental Data, Alexander S. Zhilin, Valeria R. Ramazanova, Joseph William Newkirk, Tarak A. Amine, Deborah Alvarenga Dec 2016

Computational Modelling For Phase Transformation Prediction In Super-Invar Alloys: Analytical And Experimental Data, Alexander S. Zhilin, Valeria R. Ramazanova, Joseph William Newkirk, Tarak A. Amine, Deborah Alvarenga

Materials Science and Engineering Faculty Research & Creative Works

The possibility of using computational modelling to predict phase transformation processes has been shown while examining super-invar samples. Due to the complicity of phase transformation processes in these alloys the correlation between modelling and experimental work has been described. Modelling allows basic background of composition behavior to be predicted but it doesn`t give the real structure components.


Multimodal Spontaneous Emotion Corpus For Human Behavior Analysis, Zheng Zhang, Jeffrey M. Girard, Yue Wu, Xing Zhang, Peng Liu, Umur Ciftci, Shaun Canavan, Michael Reale, Andrew Horowitz, Huiyuan Yang, Jeffrey F. Cohn, Qiang Ji, Lijun Yin Dec 2016

Multimodal Spontaneous Emotion Corpus For Human Behavior Analysis, Zheng Zhang, Jeffrey M. Girard, Yue Wu, Xing Zhang, Peng Liu, Umur Ciftci, Shaun Canavan, Michael Reale, Andrew Horowitz, Huiyuan Yang, Jeffrey F. Cohn, Qiang Ji, Lijun Yin

Computer Science Faculty Research & Creative Works

Emotion is expressed in multiple modalities, yet most research has considered at most one or two. This stems in part from the lack of large, diverse, well-annotated, multimodal databases with which to develop and test algorithms. We present a well-annotated, multimodal, multidimensional spontaneous emotion corpus of 140 participants. Emotion inductions were highly varied. Data were acquired from a variety of sensors of the face that included high-resolution 3D dynamic imaging, high-resolution 2D video, and thermal (infrared) sensing, and contact physiological sensors that included electrical conductivity of the skin, respiration, blood pressure, and heart rate. Facial expression was annotated for both …


Birth Mass Is The Key To Understanding The Negative Correlation Between Lifespan And Body Size In Dogs, Rong Fan, Gayla R. Olbricht, Xavior Baker, Chen Hou Dec 2016

Birth Mass Is The Key To Understanding The Negative Correlation Between Lifespan And Body Size In Dogs, Rong Fan, Gayla R. Olbricht, Xavior Baker, Chen Hou

Mathematics and Statistics Faculty Research & Creative Works

Larger dog breeds live shorter than the smaller ones, opposite of the mass-lifespan relationship observed across mammalian species. Here we use data from 90 dog breeds and a theoretical model based on the first principles of energy conservation and life history tradeoffs to explain the negative correlation between longevity and body size in dogs. We found that the birth/adult mass ratio of dogs scales negatively with adult size, which is different than the weak interspecific scaling in mammals. Using the model, we show that this ratio, as an index of energy required for growth, is the key to understanding why …


Toward Transparency And Broader Safeguards Conclusion: A Closer Look At The Proposed Saudi’S Civilian Nuclear Power Program, Thaqal Alhuzaymi, Ayodeji Babatunde Alajo Dec 2016

Toward Transparency And Broader Safeguards Conclusion: A Closer Look At The Proposed Saudi’S Civilian Nuclear Power Program, Thaqal Alhuzaymi, Ayodeji Babatunde Alajo

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

The higher the transparency of any civilian nuclear power program, the higher the chance of attracting and securing the long-term foreign nuclear cooperation. For newcomer states, securing nuclear cooperation is essential for successful deployment and implementation of nuclear power program. Complying with an acceptable types of safeguards commitment/protocols plays a major role in increasing transparency. The determination of transparency primarily relies on the presence of sensitive nuclear isotopes–as defined under IAEA’s safeguards–with a nuclear facility. Kingdom of Saudi Arabia (KSA) is considering the deployment of civilian nuclear power program with a projected nuclear capacity ~18 gigawatt-electric (GWe) by 2032-40. The …


Enhancements In Localized Classification For Uterine Cervical Cancer Digital Histology Image Assessment, Peng Guo, Haidar A. Almubarak, Koyel Banerjee, R. Joe Stanley, L. Rodney Long, Sameer K. Antani, George R. Thoma, Rosemary E. Zuna, Shelliane R. Frazier, Randy Hays Moss, William V. Stoecker Dec 2016

Enhancements In Localized Classification For Uterine Cervical Cancer Digital Histology Image Assessment, Peng Guo, Haidar A. Almubarak, Koyel Banerjee, R. Joe Stanley, L. Rodney Long, Sameer K. Antani, George R. Thoma, Rosemary E. Zuna, Shelliane R. Frazier, Randy Hays Moss, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

Background: In previous research, we introduced an automated, localized, fusion-based approach for classifying uterine cervix squamous epithelium into Normal, CIN1, CIN2, and CIN3 grades of cervical intraepithelial neoplasia (CIN) based on digitized histology image analysis. As part of the CIN assessment process, acellular and atypical cell concentration features were computed from vertical segment partitions of the epithelium region to quantize the relative distribution of nuclei.

Methods: Feature data was extracted from 610 individual segments from 61 images for epithelium classification into categories of Normal, CIN1, CIN2, and CIN3. The classification results were compared against CIN labels obtained from two pathologists …


A Hypothesis Testing Approach For Topology Error Detection In Power Grids, Wei Biao Wu, Maggie X. Cheng, Bei Gou Dec 2016

A Hypothesis Testing Approach For Topology Error Detection In Power Grids, Wei Biao Wu, Maggie X. Cheng, Bei Gou

Computer Science Faculty Research & Creative Works

When the grid topology is changed due to incidents and the state estimator is not updated with the topological change, it is considered a topology error. In this paper, we develop a new method for detecting topology errors in power grids. The proposed method considers the measurement data as a nonstationary Gaussian process, explores the dependence structure of the underlying process. It detects errors by testing the hypothesis of whether the mean vector of a nonstationary Gaussian process is zero and does not rely on the convergence of the standard weighted least-squares (WLS) state estimation algorithm. It is very effective …


On The Vulnerabilities Of Voronoi-Based Approaches To Mobile Sensor Deployment, Novella Bartolini, Stefano Ciavarella, Simone Silvestri, Thomas La Porta Dec 2016

On The Vulnerabilities Of Voronoi-Based Approaches To Mobile Sensor Deployment, Novella Bartolini, Stefano Ciavarella, Simone Silvestri, Thomas La Porta

Computer Science Faculty Research & Creative Works

Mobile sensor networks are the most promising solution to cover an Area of Interest (AoI) in safety critical scenarios. Mobile devices can coordinate with each other according to a distributed deployment algorithm, without resorting to human supervision for device positioning and network configuration. In this paper, we focus on the vulnerabilities of the deployment algorithms based on Voronoi diagrams to coordinate mobile sensors and guide their movements. We give a geometric characterization of possible attack configurations, proving that a simple attack consisting of a barrier of few compromised sensors can severely reduce network coverage. On the basis of the above …


Mixed-Criticality Scheduling To Minimize Makespan, Sanjoy K. Baruah, Arvind Easwaran, Zhishan Guo Dec 2016

Mixed-Criticality Scheduling To Minimize Makespan, Sanjoy K. Baruah, Arvind Easwaran, Zhishan Guo

Computer Science Faculty Research & Creative Works

In the mixed-criticality job model, each job is characterized by two execution time parameters, representing a smaller (less conservative) estimate and a larger (more conservative) estimate on its actual, unknown, execution time. Each job is further classified as being either less critical or more critical. The desired execution semantics are that all jobs should execute correctly provided all jobs complete upon being allowed to execute for up to the smaller of their execution time estimates, whereas if some jobs need to execute beyond their smaller execution time estimates (but not beyond their larger execution time estimates), then only the jobs …


Ground-Penetrating Radar Water Content Mapping Of Golf Course Green Sand Layers, Barry J. Allred, Robert S. Freeland, Katherine R. Grote, Edward L. Mccoy, Luis R. Martinez, Debra L. Gamble Dec 2016

Ground-Penetrating Radar Water Content Mapping Of Golf Course Green Sand Layers, Barry J. Allred, Robert S. Freeland, Katherine R. Grote, Edward L. Mccoy, Luis R. Martinez, Debra L. Gamble

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Information on the spatial distribution of water content across the sand layer component of a golf course green can be important to golf course superintendents for evaluating drainage effectiveness and scheduling irrigation. To estimate the bulk volumetric water content of the sand layer at point locations across the green, a technique was developed that combined (1) depth (or thickness) of the sand layer measured with a steel shaft tile probe, (2) radar signal two-way travel time from the base of the sand layer obtained using a ground-penetrating radar (GPR) system with 900 MHz antennas, and (3) an empirical equation relating …


Dermal Uptake Directly From Air Under Transient Conditions: Advances In Modeling And Comparisons With Experimental Results For Human Subjects, G. C. Morrison, C. J. Weschler, G. Bekö Dec 2016

Dermal Uptake Directly From Air Under Transient Conditions: Advances In Modeling And Comparisons With Experimental Results For Human Subjects, G. C. Morrison, C. J. Weschler, G. Bekö

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

To better understand the dermal exposure pathway, we enhance an existing mechanistic model of transdermal uptake by including skin surface lipids (SSL) and consider the impact of clothing. Addition of SSL increases the overall resistance to uptake of SVOCs from air but also allows for rapid transfer of SVOCs to sinks like clothing or clean air. We test the model by simulating di-ethyl phthalate (DEP) and di-n-butyl phthalate (DnBP) exposures of six bare-skinned (Weschler et al. 2015, Environ. Health Perspect., 123, 928) and one clothed participant (Morrison et al. 2016, J. Expo. Sci. Environ. Epidemiol., 26, 113). The model predicts …


Cloud-Enhanced Robotic System For Smart City Crowd Control, Akhlaqur Rahman, Jiong Jin, Antonio Cricenti, Ashfaqur Rahman, Marimuthu Palaniswami, Tony Tie Luo Dec 2016

Cloud-Enhanced Robotic System For Smart City Crowd Control, Akhlaqur Rahman, Jiong Jin, Antonio Cricenti, Ashfaqur Rahman, Marimuthu Palaniswami, Tony Tie Luo

Computer Science Faculty Research & Creative Works

Cloud robotics in smart cities is an emerging paradigm that enables autonomous robotic agents to communicate and collaborate with a cloud computing infrastructure. It complements the Internet of Things (IoT) by creating an expanded network where robots offload data-intensive computation to the ubiquitous cloud to ensure quality of service (QoS). However, offloading for robots is significantly complex due to their unique characteristics of mobility, skill-learning, data collection, and decision-making capabilities. In this paper, a generic cloud robotics framework is proposed to realize smart city vision while taking into consideration its various complexities. Specifically, we present an integrated framework for a …


Shear Wave Velocity And Its Anisotropy Of Polymer Modified High-Volume Class-F Fly Ash-Kaolinite Mixtures, X. Kang, B. Bate Dec 2016

Shear Wave Velocity And Its Anisotropy Of Polymer Modified High-Volume Class-F Fly Ash-Kaolinite Mixtures, X. Kang, B. Bate

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigated the effects of polymers on the small-strain stiffness behavior of high-volume Class-F fly ash-kaolinite mixtures. The shear wave velocity (Vs) and its anisotropy of organically modified fly ash-kaolinite mixtures were evaluated using a self-developed floating wall type consolidometer bender element (BE) testing system. Both synthetic polymers [polyethylene oxide (PEO)] and biopolymers (xanthan gum and chitosan) were used to modify the stiffness of fly ash-kaolinite mixtures. Shear waves generated and received by bender elements were measured to quantify the small-strain stiffness of the organically modified fly ash-kaolinite mixtures in three orthogonal directions, i.e., vh, hv, and hh. The …


Underwater Image Enhancement Strategy With Virtual Retina Model And Image Quality Assessment, Yaomin Wang, Ruijie Chang, Ruinian, Bo He, Xunfei Liu, Jen Hwa Guo, Amaury Lendasse Nov 2016

Underwater Image Enhancement Strategy With Virtual Retina Model And Image Quality Assessment, Yaomin Wang, Ruijie Chang, Ruinian, Bo He, Xunfei Liu, Jen Hwa Guo, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

Underwater Image Enhancement is One of the Most Essential and Fundamental Tasks in Ocean Investigations Recent Years. in This Paper, We Made an Attempt to Develop One Adaptive Underwater Image Enhancement Approach with the Help of the Virtual Retina Model and the Image Quality Assessment (IQA). the Virtual Retina Model, Which Yields Comparatively High Correlation with the Human Vision System, is First Taken to Achieve Simultaneous Ambiguity Removing and Detail Enhancing of Single Image Due to the Specific Mechanisms of Different Retinal Sub-Layers. after This, an Adaptive Image Enhancement Strategy is Taken with One Kind of No-Reference Image Quality Assessment …


Underwater Non-Rigid 3d Shape Reconstruction Via Structure From Motion For Fish Ethology Research, Renzheng Che, Xiao Xu, Rui Nian, Bo He, Meimei Chen, Cheng Zhang, Amaury Lendasse Nov 2016

Underwater Non-Rigid 3d Shape Reconstruction Via Structure From Motion For Fish Ethology Research, Renzheng Che, Xiao Xu, Rui Nian, Bo He, Meimei Chen, Cheng Zhang, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

In This Paper, We Try to Develop a General Framework of 3d Shape Reconstruction Strategy with Extremely Rare Point Cloud Extracted for Fish Ethology Research. Particle Filter is First Taken to Focus on Fish Trajectory Tracking from Monocular Video Sequence. the Speeded Up Robust Features (Surf) Technique Will Be Adopted to Match the Same Tracking Fish Across the overlapping View Fields with More Stable and Accurate Features. Non-Rigid 3d Shape Reconstruction Will Be Finally Developed with the Help of Expectation Maximization (Em) Model and Linear Dynamical System (LDS). It is Shown from Our Simulation Experiment that the Developed Scheme of …


Reduced Order Models For Profiled Steel Diaphragm Panels, G. Bian, S. Torabian, B. W. Schafer Nov 2016

Reduced Order Models For Profiled Steel Diaphragm Panels, G. Bian, S. Torabian, B. W. Schafer

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The objective of this paper is to provide progress on development and validation of reduced order models for the in plane strength and stiffness of profiled steel panels appropriate for use in structural models of an entire building. Profiled steel panels, i.e, metal deck, often serve as a key distribution element in building lateral force resisting systems. Acting largely as an in-plane shear diaphragm, metal deck as employed in walls, roofs, and floors plays a key role in creating and driving three-dimensional building response. As structural modeling evolves from two-dimensional frameworks to fully three-dimensional buildings, accurate and computationally efficient models …


On The Direct Strength Design Of Cold-Formed Steel Columns Falling In Local-Distortional Interactive Modes, André Dias Martins, Dinar Camotim, Pedro Borges Dinis Nov 2016

On The Direct Strength Design Of Cold-Formed Steel Columns Falling In Local-Distortional Interactive Modes, André Dias Martins, Dinar Camotim, Pedro Borges Dinis

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper present and discusses proposals for the codification of efficient design approaches for cold-formed steel columns affected by local-distortional (L-D) interaction. These proposals, based on the Direct Strength Method (DSM), were developed, calibrated and validated on the basis of experimental and numerical (shell finite element) failure load data concerning columns with several cross-section shapes and obtained from investigations carried out by various researchers. Three types of L-D interaction are taken into account, namely “true L-D interaction”, “secondary local bifurcation L-D interaction” and “secondary distortional bifurcation L-D interaction”. Moreover, previously available DSM-based design approaches to handle column L-D interactive failures …


Proposal For Codification Of A Dsm Design Approach For Cold-Formed Steel Short-To Intermediate Angle Columns, Pedro Borges Dinis, Dinar Camotim Nov 2016

Proposal For Codification Of A Dsm Design Approach For Cold-Formed Steel Short-To Intermediate Angle Columns, Pedro Borges Dinis, Dinar Camotim

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents a proposal for the codification of an efficient design approach for cold-formed steel short-to-intermediate equal-leg angle columns, consisting of a slight modification of a design approach developed by Dinis & Camotim (2015) and based on the Direct Strength Method (DSM). After (i) collecting the available experimental and numerical failure load data, comprising fixed-ended and pin-ended columns with several geometries (cross-section dimensions and length) and reported by various researchers, and (ii) briefly reviewing the mechanical reasoning behind the proposed procedures, the search for new/simpler expressions to provide the DSM design curves is addressed. Their merits are assessed through …


Wei-Wen Yu International Specialty Conference On Cold-Formed Steel Structures 2016: Recent Research And Developments In Cold-Formed Steel Structures, Wei-Wen Yu Center For Cold-Formed Steel Structures Nov 2016

Wei-Wen Yu International Specialty Conference On Cold-Formed Steel Structures 2016: Recent Research And Developments In Cold-Formed Steel Structures, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.


First-Order Generalized Beam Theory For Curved Members With Circular Axis, Nuno Peres, Rodrigo Gonçalves, Dinar Camotim Nov 2016

First-Order Generalized Beam Theory For Curved Members With Circular Axis, Nuno Peres, Rodrigo Gonçalves, Dinar Camotim

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents a first-order Generalized Beam Theory (GBT) formulation for thin-walled members with circular axis and undergoing complex global-distortional-local deformation. The fundamental equations are derived on the basis of the usual GBT kinematic assumptions (Kirchhoff, Vlasov and wall in-plane inextensibility), leading to a formulation able to retrieve accurate solutions with only a few cross-section deformation modes (cross-section DOFs). It is shown that the classic Winkler and Vlasov theories can be recovered from the derived formulation. A GBT-based finite element is use to analyze numerical examples illustrating the application and potential of the proposed formulation.


Stability Analysis Of Thin-Walled Members With Curved Cross-Section Parts: Inelastic Behavior, D. Jobbágy, S. Ádány Nov 2016

Stability Analysis Of Thin-Walled Members With Curved Cross-Section Parts: Inelastic Behavior, D. Jobbágy, S. Ádány

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

In this paper the buckling behavior of thin-walled members with cross-sections with curved parts is investigated. Due to the curved parts, shell-like buckling is a potential mode of failure. The objective of the research is to understand whether shell-like buckling behavior might be governing in practical cold-formed steel members. For this aim, numerical studies have been carried out, involving linear buckling analysis as well as nonlinear analysis with imperfections, by considering various cross-sections. Based on the results it is concluded that shell-like behavior might be critical in certain cases.


Advancing Bim For Cold-Formed Steel Structures, Adam Johnson, Roni Ramirez, Cheng Yu Nov 2016

Advancing Bim For Cold-Formed Steel Structures, Adam Johnson, Roni Ramirez, Cheng Yu

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper presents a research project aimed at advancing BIM for cold-formed steel (CFS) structures. The creation of the CFS family for Autodesk Revit is a handy solution for the lack of CFS members and information inside the Autodesk Revit libraries. Revit is one of the industry’s standard software for producing building information models. To overcome the disadvantages of not having CFS members in Revit, this research project focused on two phases to reach completion. Phase one consisted of developing a BIM library of industrial standard CFS members such as studs, tracks, and channels. Parameters were added to the members …


A Study Of Scattering From A Layer Of Random Discrete Medium With Hierarchical Equivalent Source Algorithm (Hesa), Chan Fai Lum, Fu Xin, Hong Tat Ewe, Li (Lijun) Jun Jiang Nov 2016

A Study Of Scattering From A Layer Of Random Discrete Medium With Hierarchical Equivalent Source Algorithm (Hesa), Chan Fai Lum, Fu Xin, Hong Tat Ewe, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper is to present a new numerical method which can be used in computational electromagnetics in microwave remote sensing of random discrete medium embedded with irregular shape of scatterers. Current Radiative Transfer (RT) theoretical modeling is normally used to simulate wave propagation in the medium and wave scattering by basic shapes of scatterers, e.g., cylinder, disk, needle or sphere where the scattering of those scatterers was normally derived analytically with some assumption and approximation. To simulate the total backscattering coefficient from a layer of random medium, traditionally it was quite common that Mie phase matrix was used to compute …


Right-Hand Side Effect On The Convergence Of Integral Equation Based Systems, Qin S. Liu, Sheng Sun, Weng Cho Chew, Qi I. Dai, Li (Lijun) Jun Jiang Nov 2016

Right-Hand Side Effect On The Convergence Of Integral Equation Based Systems, Qin S. Liu, Sheng Sun, Weng Cho Chew, Qi I. Dai, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

A study of the right-hand side effect for an iterative solver is presented. The right-hand side determines whether a mode can be excited under certain excitation. Based on the matrix equation system Ā · x = b, different formulations are discussed including the electric field integral equation (EFIE), Calderón preconditioned EFIE with electro-quasi-static problems, and the magnetic integral equation (MFIE) with magneto-quasi-static problems. Detailed spectral analysis shows the importance of the weighted right-hand side effect in both the convergence and accuracy of iterative system.


Passive Rifting Of Thick Lithosphere In The Southern East African Rift: Evidence From Mantle Transition Zone Discontinuity Topography, Cory A. Reed, Kelly H. Liu, Patrick R. N. Chindandali, Belarmino Massingue, Hassan Mdala, Daniel Mutamina, Youqiang Yu, Stephen S. Gao Nov 2016

Passive Rifting Of Thick Lithosphere In The Southern East African Rift: Evidence From Mantle Transition Zone Discontinuity Topography, Cory A. Reed, Kelly H. Liu, Patrick R. N. Chindandali, Belarmino Massingue, Hassan Mdala, Daniel Mutamina, Youqiang Yu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To investigate the mechanisms for the initiation and early-stage evolution of the nonvolcanic southernmost segments of the East African Rift System (EARS), we installed and operated 35 broadband seismic stations across the Malawi and Luangwa rift zones over a 2 year period from mid-2012 to mid-2014. Stacking of over 1900 high-quality receiver functions provides the first regional-scale image of the 410 and 660 km seismic discontinuities bounding the mantle transition zone (MTZ) within the vicinity of the rift zones. When a 1-D standard Earth model is used for time-depth conversion, a normal MTZ thickness of 250 km is found beneath …


Mantle Structure Beneath The Incipient Okavango Rift Zone In Southern Africa, Youqiang Yu, Kelly H. Liu, Zhouchuan Huang, Dapeng Zhao, Cory A. Reed, Moikwathai Moidaki, Jianshe Lei, Stephen S. Gao Nov 2016

Mantle Structure Beneath The Incipient Okavango Rift Zone In Southern Africa, Youqiang Yu, Kelly H. Liu, Zhouchuan Huang, Dapeng Zhao, Cory A. Reed, Moikwathai Moidaki, Jianshe Lei, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Numerous investigations of the mature segments of the East African rift system (EARS) have significantly improved our understanding of the structure and processes associated with well-developed continental rifts. In contrast, knowledge of rifting processes at their early stage is still significantly limited. Here we present results from a teleseismic P-wave tomography investigation of the incipient Okavango rift zone (ORZ), which is located at the southwestern terminus of the EARS. P-wave relative travel-time residuals recorded by 17 recently deployed portable seismic stations were manually picked and inverted for three-dimensional upper-mantle and mantle transition-zone tomographic images beneath the ORZ and its adjacent …