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Articles 931 - 960 of 3445
Full-Text Articles in Engineering
Early Assessment Of Burn Severity In Human Tissue With Multi-Wavelength Spatial Frequency Domain Imaging, Chien Sing Poon
Early Assessment Of Burn Severity In Human Tissue With Multi-Wavelength Spatial Frequency Domain Imaging, Chien Sing Poon
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Burn injuries such as thermal burns, which are caused by contact with flames, hot liquids, hot surfaces, and other sources of high heat as well as chemical burns and electrical burns, affects at least 500,000 people in the United States, to which 45,000 of them require medical treatment and 3,500 of them result in death. It has also been reported that in the United States alone, fire results in a death approximately every three hours and an injury every 33 minutes. Early knowledge about burn severity can lead to improved outcome for patients. In this study, the changes in optical …
On The Experimental Evaluation Of Loss Production And Reduction In A Highly Loaded Low Pressure Turbine Cascade, Philip Steven Bear
On The Experimental Evaluation Of Loss Production And Reduction In A Highly Loaded Low Pressure Turbine Cascade, Philip Steven Bear
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Improvements in turbine design methods have resulted in the development of blade profiles with both high lift and good Reynolds lapse characteristics. An increase in aerodynamic loading of blades in the low pressure turbine section of aircraft gas turbine engines has the potential to reduce engine weight or increase power extraction. Increased blade loading means larger pressure gradients and increased secondary losses near the endwall. Prior work has emphasized the importance of reducing these losses if highly loaded blades are to be utilized. The present study analyzes the secondary flow field of the front-loaded low-pressure turbine blade designated L2F with …
Optical Redox Imaging Of Metabolic Activity, Syed Anwar Hyder Zaidi
Optical Redox Imaging Of Metabolic Activity, Syed Anwar Hyder Zaidi
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Fluorescence imaging can be used to determine tissue metabolism, which is an indication of the cellular functionality. Metabolic contrast is useful for the early detection of several medical conditions such as cancer, diabetes, lung diseases etc. This study aims to use fluorescence imaging to quantify NADH and FAD, which are cellular metabolic indicators. A parameter known as Redox ratio, can be used to study metabolic state of several tissue types and disease states. To quantify the Redox ratio, three fluorescence imaging systems were optimized to measure the fluorescence signal from NADH and FAD. The first system was a camera based …
Distributed Rule-Based Ontology Reasoning, Raghava Mutharaju
Distributed Rule-Based Ontology Reasoning, Raghava Mutharaju
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The vision of the Semantic Web is to provide structure and meaning to the data on the Web. Knowledge representation and reasoning play a crucial role in accomplishing this vision. OWL (Web Ontology Language), a W3C standard, is used for representing knowledge. Reasoning over the ontologies is used to derive logical consequences. A fixed set of rules are run on an ontology iteratively until no new logical consequences can be derived. All existing reasoners run on a single machine, possibly using multiple cores. Ontologies (sometimes loosely referred to as knowledge bases) that are automatically constructed can be very large. Single …
Customizable 3-D Virtual Gi Tract Systems For Locating, Mapping, And Navigation Inside Human Gastrointestinal Tract, Megha Dattatrey Dalvi
Customizable 3-D Virtual Gi Tract Systems For Locating, Mapping, And Navigation Inside Human Gastrointestinal Tract, Megha Dattatrey Dalvi
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One of the critical challenges of wireless capsule endoscopy examination is to find the exact position of the capsule in the Gastrointestinal Tract (GI) tract so as to correctly and accurately spot the position of the intestinal diseases. Creating a 3D virtual GI tract system could significantly improve the capsule endoscopy operations. The virtual human model, such as the BioDigital Human, has been credited as Google Earth for the human body, which provides us medically accurate virtual body and organ structures. However, it only assembles a “Standard” human body. The problem is: there is only one earth, but billions of …
Augment Hololens’ Body Recognition And Tracking Capabilities Using Kinect, Krishna Chaithanya Mathi
Augment Hololens’ Body Recognition And Tracking Capabilities Using Kinect, Krishna Chaithanya Mathi
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In this thesis, we are primarily interested in exploring the HoloLens technologies for medical practices. Particularly, we will address the limitation of HoloLens’ capability in human body sensing, recognition and tracking. We will then introduce and demonstrate the use of Kinect to augment HoloLens’ sensory and processing capabilities in order to produce time and space-synchronized immersive environment with both virtual body and real body of the same patient for supporting distributed medical collaborations. Specifically, we are looking at a distributed solution in which we are collecting the patient body data from Kinect, followed by body recognition and position/motion tracking processing …
Novel Cost And Space Efficient Range Of Motion And Gait Analysis Systems, Rutvik Bharatkumar Patel
Novel Cost And Space Efficient Range Of Motion And Gait Analysis Systems, Rutvik Bharatkumar Patel
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In this thesis, we have explored the use of the latest motion tracking technologies, as evident by Microsoft Xbox Kinect’s motion tracking capabilities, in combination with 3D digital human modeling and animation, multi-modality image capturing and processing, and fusion, to design a new generation of low-cost range of motion and gait analysis solutions that overcome the limitation of existing tools. The proposed solutions and our prototype systems have demonstrated accurate measurements and reliable analysis outcome compared to current clinic practices, with significantly reduced complexity and cost. Furthermore, it eliminates the need for expensive effort for pre- and post- processing of …
Adaptive Power Analog-To-Digital Interface For Digital Systems, Todd S. Grimes
Adaptive Power Analog-To-Digital Interface For Digital Systems, Todd S. Grimes
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Today many consumer, industrial, and military electronic systems are digital in nature and are utilized for multiple applications. Many of these systems were designed to be portable and generally have limited capabilities because of size, weight, and power requirements. The last several decades have seen the push for more power efficient electronics. Thus, researchers and scientists investigated advanced process technologies and more power efficient circuit implementations. This research is concerned with classes of applications intended to operate over long periods of time with a low duty cycle, but are subject to bursts of information, requiring high processing capabilities. Specifically, this …
On The Discovery Of Social Roles In Large Scale Social Systems, Derek Doran
On The Discovery Of Social Roles In Large Scale Social Systems, Derek Doran
Computer Science and Engineering Faculty Publications
The social role of a participant in a social system is a label conceptualizing the circumstances under which she interacts within it. They may be used as a theoretical tool that explains why and how users participate in an online social system. Social role analysis also serves practical purposes, such as reducing the structure of complex systems to relationships among roles rather than alters, and enabling a comparison of social systems that emerge in similar contexts. This article presents a data-driven approach for the discovery of social roles in large scale social systems. Motivated by an analysis of the present …
Flight Physician - November, 2015, Civil Aviation Medical Association
Flight Physician - November, 2015, Civil Aviation Medical Association
Browse all Civil Aviation Medical Association Newsletters
A twenty-one page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.
The Effect Of A Reversible Shear Transformation On Plastic Deformation Of An Amorphous Solid, Nikolai V. Priezjev
The Effect Of A Reversible Shear Transformation On Plastic Deformation Of An Amorphous Solid, Nikolai V. Priezjev
Mechanical and Materials Engineering Faculty Publications
Molecular dynamics simulations are performed to investigate the plastic response of a model glass to a local shear transformation in a quiescent system. The deformation of the material is induced by a spherical inclusion that is gradually strained into an ellipsoid of the same volume and then reverted back into the sphere. We show that the number of cage-breaking events increases with increasing strain amplitude of the shear transformation. The results of numerical simulations indicate that the density of cage jumps is larger in the cases of weak damping or slow shear transformation. Remarkably, we also found that, for a …
Analysis Of A Clinically Failed, Mechanically Intact, Reconstructive Compression Plate, Bharadwaj Cheruvu, Sunil Karmacharya, Richard T. Laughlin, Tarun Goswami
Analysis Of A Clinically Failed, Mechanically Intact, Reconstructive Compression Plate, Bharadwaj Cheruvu, Sunil Karmacharya, Richard T. Laughlin, Tarun Goswami
Biomedical, Industrial & Human Factors Engineering Faculty Publications
A reconstructive orthopedic bone plate was submitted for analysis. Traditional failure analysis methods were used to assess the mode of the plate failure. Metallographic investigation of the plate was carried out in this report. Since limited data was available in the literature and clinical data related to subject demography, date of removal as well as reasons for removal unknown, in depth analysis was not possible. However, the plate was received in in-tact condition with minor biological deposits and scratches, it is speculated that the failure of the plate may have been due to biological/clinical reasons, likely infection, rejecting the device …
Stay Awhile And Listen: User Interactions In A Crowdsourced Platform Offering Emotional Support, Derek Doran, Samir P. Yelne, Luisa Massari, Maria-Carla Calzarossa, Latrelle D. Jackson, Glen Moriarty
Stay Awhile And Listen: User Interactions In A Crowdsourced Platform Offering Emotional Support, Derek Doran, Samir P. Yelne, Luisa Massari, Maria-Carla Calzarossa, Latrelle D. Jackson, Glen Moriarty
Computer Science and Engineering Faculty Publications
Internet and online-based social systems are rising as the dominant mode of communication in society. However, the public or semi-private environment under which most online communications operate under do not make them suitable channels for speaking with others about personal or emotional problems. This has led to the emergence of online platforms for emotional support offering free, anonymous, and confidential conversations with live listeners. Yet very little is known about the way these platforms are utilized, and if their features and design foster strong user engagement. This paper explores the utilization and the interaction features of hundreds of thousands of …
Safety And Efficacy Results Of Switch From Imiglucerase To Velaglucerase Alfa Treatment In Patients With Type 1 Gaucher Disease, Deborah Elstein, Atul Mehta, Derralynn A. Hughes, Pilar Giraldo, Joel Charrow, Laurie Smith, Suma P. Shankar, Thomas N. Hangartner, Yune Kunes, Nan Wang, Eric Crombez, Ari Zimran
Safety And Efficacy Results Of Switch From Imiglucerase To Velaglucerase Alfa Treatment In Patients With Type 1 Gaucher Disease, Deborah Elstein, Atul Mehta, Derralynn A. Hughes, Pilar Giraldo, Joel Charrow, Laurie Smith, Suma P. Shankar, Thomas N. Hangartner, Yune Kunes, Nan Wang, Eric Crombez, Ari Zimran
Biomedical, Industrial & Human Factors Engineering Faculty Publications
Gaucher disease (GD) is a lysosomal storage disorder; symptomatic patients with type 1 GD need long-term disease-specific therapy of which the standard of care has been enzyme replacement therapy (ERT). Thirty-eight of 40 patients (aged 9–71 years) clinically stable on ERT with imiglucerase, safely switched to a comparable dose of velaglucerase alfa (units/kg) during TKT034, a 12-month, open-label clinical study, and for 10–50 months in an extension study. The most common adverse events (AEs) judged to be drug-related in the extension were fatigue and bone pain. No drug-related serious AEs were reported. No AEs led to study withdrawal. At 24 …
Velaglucerase Alfa (Vpriv) Enzyme Replacement Therapy In Patients With Gaucher Disease: Long-Term Data From Phase Iii Clinical Trials, Derralynn A. Hughes, Derlis Gonzalez, Elena A. Lukina, Atul Mehta, Madhulika Kabra, Deborah Elstein, Isaac Kisinovsky, Pilar Giraldo, Ashish Bavdekar, Thomas N. Hangartner, Nan Wang, Eric Crombez, Ari Zimran
Velaglucerase Alfa (Vpriv) Enzyme Replacement Therapy In Patients With Gaucher Disease: Long-Term Data From Phase Iii Clinical Trials, Derralynn A. Hughes, Derlis Gonzalez, Elena A. Lukina, Atul Mehta, Madhulika Kabra, Deborah Elstein, Isaac Kisinovsky, Pilar Giraldo, Ashish Bavdekar, Thomas N. Hangartner, Nan Wang, Eric Crombez, Ari Zimran
Biomedical, Industrial & Human Factors Engineering Faculty Publications
Type 1 Gaucher disease is an inherited lysosomal enzyme deficiency with variable age of symptom onset. Common presenting signs include thrombocytopenia, anemia, hepatosplenomegaly, bone abnormalities, and, additionally in children, growth failure. Fifty-seven patients aged 3–62 years at the baseline of two phase III trials for velaglucerase alfa treatment were enrolled in the single extension study. In the extension, they received every-other-week velaglucerase alfa intravenous infusions for 1.2–4.8 years at 60 U/kg, although 10 patients experienced dose reduction. No patient experienced a drug-related serious adverse event or withdrew due to an adverse event. One patient died following a convulsion that was …
Diffusion Of A Janus Nanoparticle In An Explicit Solvent: A Molecular Dynamics Simulation Study, Ali Kharazmi, Nikolai V. Priezjev
Diffusion Of A Janus Nanoparticle In An Explicit Solvent: A Molecular Dynamics Simulation Study, Ali Kharazmi, Nikolai V. Priezjev
Mechanical and Materials Engineering Faculty Publications
Molecular dynamics simulations are carried out to study the translational and rotational diffusion of a single Janus particle immersed in a dense Lennard-Jones fluid. We consider a spherical particle with two hemispheres of different wettabilities. The analysis of the particle dynamics is based on the time-dependent orientation tensor, particle displacement, as well as the translational and angular velocity autocorrelation functions. It was found that both translational and rotational diffusion coefficients increase with decreasing surface energy at the nonwetting hemisphere, provided that the wettability of the other hemisphere remains unchanged. We also observed that in contrast to homogeneous particles, the nonwetting …
Toe Joint Replacement Models, Tarun Goswami, Allison L. Van Horn, Alexander O. Sheets
Toe Joint Replacement Models, Tarun Goswami, Allison L. Van Horn, Alexander O. Sheets
Biomedical, Industrial & Human Factors Engineering Faculty Publications
In various embodiments, provided are implantable devices for replacing all or a portion of a metatarsophalangeal joint, comprising (i) a metatarsal component comprising a Substan tially convex bearing Surface; or (ii) a phalanx component comprising a Substantially concave bearing Surface; or (iii) both. In various embodiments, also provided are methods of treating hallux Valgus by replacing all or a portion of a meta tarsophalangeal joint with one or more of the provided implantable devices.
Flight Physician - May, 2015, Civil Aviation Medical Association
Flight Physician - May, 2015, Civil Aviation Medical Association
Browse all Civil Aviation Medical Association Newsletters
A seventeen page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.
Where Do We Develop? Discovering Regions For Urban Investment In Senegal, Derek Doran, Andrew Fox, Veena Mendiratta
Where Do We Develop? Discovering Regions For Urban Investment In Senegal, Derek Doran, Andrew Fox, Veena Mendiratta
Computer Science and Engineering Faculty Publications
The rate of urbanization in developing countries, defined as the speed with which a population shifts from rural to urban areas, is among the highest in the world. The disproportionate number of citizens that live in a small numbers of cities places incredible pressure on the largest cities in these countries, which may already be faced with limited resources, weak industrialization, and underdeveloped infrastructures. Urban planning researchers as well as policy makers have suggested that governments in developing countries make capital investments within and surrounding smaller cities to attract citizens away from large urban centers, thereby lowering the pressure placed …
Oculomotor Neurocircuitry, A Structural Connectivity Study Of Infantile Nystagmus Syndrome, Nasser H. Kashou, Angelica R. Zampini
Oculomotor Neurocircuitry, A Structural Connectivity Study Of Infantile Nystagmus Syndrome, Nasser H. Kashou, Angelica R. Zampini
Biomedical, Industrial & Human Factors Engineering Faculty Publications
Infantile Nystagmus Syndrome (INS) is one of the leading causes of significant vision loss in children and affects about 1 in 1000 to 6000 births. In the present study, we are the first to investigate the structural pathways of patients and controls using diffusion tensor imaging (DTI). Specifically, three female INS patients from the same family were scanned, two sisters and a mother. Six regions of interest (ROIs) were created manually to analyze the number of tracks. Additionally, three ROI masks were analyzed using TBSS (Tract-Based Spatial Statistics). The number of fiber tracks was reduced in INS subjects, compared to …
Wright State University's Celebration Of Research, Scholarship And Creative Activities Book Of Abstracts From Friday, April 10, 2015, Wright State University Office Of Undergraduate Research And Stemm Activities
Wright State University's Celebration Of Research, Scholarship And Creative Activities Book Of Abstracts From Friday, April 10, 2015, Wright State University Office Of Undergraduate Research And Stemm Activities
Celebration of Undergraduate & Graduate Research, Scholarship, and Creative Activities Materials
The student abstract booklet is a compilation of abstracts from students' oral and poster presentations at Wright State University's fifth annual Celebration of Research, Scholarship and Creative Activities on April 10, 2015.
Plastic Deformation Of A Model Glass Induced By A Local Shear Transformation, Nikolai V. Priezjev
Plastic Deformation Of A Model Glass Induced By A Local Shear Transformation, Nikolai V. Priezjev
Mechanical and Materials Engineering Faculty Publications
The effect of a local shear transformation on plastic deformation of a three-dimensional amorphous solid is studied using molecular dynamics simulations. We consider a spherical inclusion, which is gradually transformed into an ellipsoid of the same volume and then converted back into the sphere. It is shown that at sufficiently large strain amplitudes, the deformation of the material involves localized plastic events that are identified based on the relative displacement of atoms before and after the shear transformation. We find that the density profiles of cage jumps decay away from the inclusion, which correlates well with the radial dependence of …
Flight Physician - March, 2015, Civil Aviation Medical Association
Flight Physician - March, 2015, Civil Aviation Medical Association
Browse all Civil Aviation Medical Association Newsletters
An eleven page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.
Compensatory Enlargement Of Ossabaw Miniature Swine Coronary Arteries In Diffuse Atherosclerosis, Jenny Susana Choy, Tong Luo, Yunlong Huo, Thomas Wischgoll, Kyle Schultz, Shawn D. Teague, Michael Sturek, Ghassan S. Kassab
Compensatory Enlargement Of Ossabaw Miniature Swine Coronary Arteries In Diffuse Atherosclerosis, Jenny Susana Choy, Tong Luo, Yunlong Huo, Thomas Wischgoll, Kyle Schultz, Shawn D. Teague, Michael Sturek, Ghassan S. Kassab
Computer Science and Engineering Faculty Publications
Studies in human and non-human primates have confirmed the compensatory enlargement or positive remodeling (Glagov phenomenon) of coronary vessels in the presence of focal stenosis. To our knowledge, this is the first study to document arterial enlargement in a metabolic syndrome animal model with diffuse coronary artery disease (DCAD) in the absence of severe focal stenosis. Two different groups of Ossabaw miniature pigs were fed a high fat atherogenic diet for 4 months (Group I) and 12 months (Group II), respectively. Group I (6 pigs) underwent contrast enhanced computed tomographic angiography (CCTA) and intravascular ultrasound (IVUS) at baseline and after …
Computational Fluid Dynamics Simulation Of Intracranial Aneurysms - Comparing Size And Shape, Zifeng Yang, Hongtao Yu, George P. Huang, Ryan Schwieterman, Bryan Ludwig
Computational Fluid Dynamics Simulation Of Intracranial Aneurysms - Comparing Size And Shape, Zifeng Yang, Hongtao Yu, George P. Huang, Ryan Schwieterman, Bryan Ludwig
Mechanical and Materials Engineering Faculty Publications
Objective: To study the hemodynamics of an anatomic internal carotid artery aneurysm derived from a patient-specific model and then manipulate into two phantom morphologies: one growing uniformly by size and the other changing shape unevenly. Methods: The computational model of the saccular, internal carotid artery, aneurysm was constructed from 3D rotational, digitally subtracted, catheter angiography images. Computational fluid dynamics simulations were performed under pulsatile cardiac flow conditions. Velocity vectors, streamlines, pressure, and wall shear stress (WSS) and its variance distributions were quantitatively visualized. Results: The maximum pressure and WSS from the time-averaged distribution on the inside saccular surface of the …
Measuring Pulse Rate Variability During Motion Artifact With A Non-Contact, Multi-Imager Photoplethysmography System, Zachary Adam Kiehl
Measuring Pulse Rate Variability During Motion Artifact With A Non-Contact, Multi-Imager Photoplethysmography System, Zachary Adam Kiehl
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Non-contact imaging photoplethysmography is an exciting new field based on the principles of traditional photoplethysmography where viable signals can now be acquired without the use of contact equipment. Recent advances regarding non-contact imaging photoplethysmography have permitted a wide range of new possibilities focused on sensing the cardiopulmonary system. Physiological metrics such as pulse rate, respiration rate, and pulse rate variability can be obtained by current photoplethysmographic imaging methods. Although previous systems were challenged by head-motion artifacts, the mitigation of rigid head-motion artifacts has been demonstrated with a multi-imager design. This study investigated the feasibility and accuracy of pulse rate variability …
High-Efficiency Wideband Class-F Power Amplifier With Electronically Tunable Resonant Network, Alex D. Compton
High-Efficiency Wideband Class-F Power Amplifier With Electronically Tunable Resonant Network, Alex D. Compton
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This thesis presents a high-efficiency Class-F power amplifier (PA) operating from 30-88 MHz through the use of an electronically tunable resonant network. While conventional Class-F designs are limited to operation over less than an octave, the proposed design utilizes reconfigurable reactive elements in order to cover the entire VHF-FM frequency range. A real circuit implementation using GaN HEMT is designed and simulated, with the notable design considerations examined in detail. A minimum power added efficiency (PAE) of 71.7% is achieved across the band, at output powers = 49.2 dBm. This combination of high output power and high-efficiency operation across a …
Large Scene Sar Image Formation, Leroy A. Gorham
Large Scene Sar Image Formation, Leroy A. Gorham
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With new advances in digital signal processing technology, Synthetic Aperture Radar (SAR) systems are capable of collecting high resolution data over very large scenes. Well known image formation algorithms such as the polar format algorithm (PFA) create image artifacts in large images due to phase errors introduced by the algorithm. In this dissertation, we analyze the nature of these artifacts by comparing PFA to an exact imaging algorithm, the backprojection algorithm (BPA). First, we perform a novel phase error analysis by decomposing the PFA phase errors into constant, linear, and quadratic terms for arbitrary flight paths. Second, we utilize the …
Direct Optimization For Classification With Boosting, Shaodan Zhai
Direct Optimization For Classification With Boosting, Shaodan Zhai
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Boosting, as one of the state-of-the-art classification approaches, is widely used in the industry for a broad range of problems. The existing boosting methods often formulate classification tasks as a convex optimization problem by using surrogates of performance measures. While the convex surrogates are computationally efficient to globally optimize, they are sensitive to outliers and inconsistent under some conditions. On the other hand, boosting's success can be ascribed to maximizing the margins, but few boosting approaches are designed to directly maximize the margin. In this research, we design novel boosting algorithms that directly optimize non-convex performance measures, including the empirical …
Contrast Pattern Aided Regression And Classification, Vahid Taslimitehrani
Contrast Pattern Aided Regression And Classification, Vahid Taslimitehrani
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Regression and classification techniques play an essential role in many data mining tasks and have broad applications. However, most of the state-of-the-art regression and classification techniques are often unable to adequately model the interactions among predictor variables in highly heterogeneous datasets. New techniques that can effectively model such complex and heterogeneous structures are needed to significantly improve prediction accuracy. In this dissertation, we propose a novel type of accurate and interpretable regression and classification models, named as Pattern Aided Regression (PXR) and Pattern Aided Classification (PXC) respectively. Both PXR and PXC rely on identifying regions in the data space where …