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Full-Text Articles in Engineering

Through-Ice Acoustic Source Tracking Using Vision Transformers With Ordinal Classification, Steven Whitaker, Andrew Barnard, George D. Anderson, Timothy C. Havens Jun 2022

Through-Ice Acoustic Source Tracking Using Vision Transformers With Ordinal Classification, Steven Whitaker, Andrew Barnard, George D. Anderson, Timothy C. Havens

Michigan Tech Publications

Ice environments pose challenges for conventional underwater acoustic localization techniques due to theirmultipath and non-linear nature. In this paper, we compare different deep learning networks, such as Transformers, Convolutional Neural Networks (CNNs), Long Short-Term Memory (LSTM) networks, and Vision Transformers (ViTs), for passive localization and tracking of single moving, on-ice acoustic sources using two underwater acoustic vector sensors. We incorporate ordinal classification as a localization approach and compare the results with other standard methods. We conduct experiments passively recording the acoustic signature of an anthropogenic source on the ice and analyze these data. The results demonstrate that Vision Transformers are …


Mobile-Polypnet: Lightweight Colon Polyp Segmentation Network For Low-Resource Settings, Ranit Karmakar, Saeid Nooshabadi Jun 2022

Mobile-Polypnet: Lightweight Colon Polyp Segmentation Network For Low-Resource Settings, Ranit Karmakar, Saeid Nooshabadi

Michigan Tech Publications

Colon polyps, small clump of cells on the lining of the colon, can lead to colorectal cancer (CRC), one of the leading types of cancer globally. Hence, early detection of these polyps automatically is crucial in the prevention of CRC. The deep learning models proposed for the detection and segmentation of colorectal polyps are resource-consuming. This paper proposes a lightweight deep learning model for colorectal polyp segmentation that achieved state-of-the-art accuracy while significantly reducing the model size and complexity. The proposed deep learning autoencoder model employs a set of state-of-the-art architectural blocks and optimization objective functions to achieve the desired …


Probabilistic Multi-Objective Inverse Analysis For Damage Identification Using Piezoelectric Impedance Measurement Under Uncertainties, Kai Zhou, Yang Zhang, Qi Shuai, Jiong Tang Jun 2022

Probabilistic Multi-Objective Inverse Analysis For Damage Identification Using Piezoelectric Impedance Measurement Under Uncertainties, Kai Zhou, Yang Zhang, Qi Shuai, Jiong Tang

Michigan Tech Publications

Piezoelectric impedance sensing is promising for highly accurate damage identification because of its high-frequency active interrogative nature and simplicity in data acquisition. To fully unleash the potential, effective inverse analysis is needed in order to pinpoint the damage location and identify the severity. The inverse analysis, however, may be underdetermined since there exists a very large number of unknowns (i.e., locations and severity levels) to be solved in a finite element model but only limited measurements are available in actual practice. To uncover the true damage scenario, an inverse analysis strategy built upon the multi-objective optimization, which aims at matching …


Kernel Matrix-Based Heuristic Multiple Kernel Learning, Stanton R. Price, Derek T. Anderson, Timothy C. Havens, Steven R. Price Jun 2022

Kernel Matrix-Based Heuristic Multiple Kernel Learning, Stanton R. Price, Derek T. Anderson, Timothy C. Havens, Steven R. Price

Michigan Tech Publications

Kernel theory is a demonstrated tool that has made its way into nearly all areas of machine learning. However, a serious limitation of kernel methods is knowing which kernel is needed in practice. Multiple kernel learning (MKL) is an attempt to learn a new tailored kernel through the aggregation of a set of valid known kernels. There are generally three approaches to MKL: fixed rules, heuristics, and optimization. Optimization is the most popular; however, a shortcoming of most optimization approaches is that they are tightly coupled with the underlying objective function and overfitting occurs. Herein, we take a different approach …


Climate Projections Over The Great Lakes Region: Using Two-Way Coupling Of A Regional Climate Model With A 3-D Lake Model, Pengfei Xue, Xinyu Ye, Jeremy S. Pal, Philip Y. Chu, Miraj Kayastha, Chenfu Huang Jun 2022

Climate Projections Over The Great Lakes Region: Using Two-Way Coupling Of A Regional Climate Model With A 3-D Lake Model, Pengfei Xue, Xinyu Ye, Jeremy S. Pal, Philip Y. Chu, Miraj Kayastha, Chenfu Huang

Michigan Tech Publications

Warming trends in the Laurentian Great Lakes and surrounding areas have been observed in recent decades, and concerns continue to rise about the pace and pattern of future climate change over the world's largest freshwater system. To date, most regional climate models used for Great Lakes projections either neglected the lake-atmosphere interactions or are only coupled with a 1-D column lake model to represent the lake hydrodynamics. This study presents a Great Lakes climate change projection that has employed the two-way coupling of a regional climate model with a 3-D lake model (GLARM) to resolve 3-D hydrodynamics essential for large …


Climate Projections Over The Great Lakes Region: Using Two-Way Coupling Of A Regional Climate Model With A 3-D Lake Model, Pengfei Xue, Xinyu Ye, Jeremy S. Pal, Philip Y. Chu, Miraj Kayastha, Chenfu Huang Jun 2022

Climate Projections Over The Great Lakes Region: Using Two-Way Coupling Of A Regional Climate Model With A 3-D Lake Model, Pengfei Xue, Xinyu Ye, Jeremy S. Pal, Philip Y. Chu, Miraj Kayastha, Chenfu Huang

Michigan Tech Publications

Warming trends in the Laurentian Great Lakes and surrounding areas have been observed in recent decades, and concerns continue to rise about the pace and pattern of future climate change over the world's largest freshwater system. To date, most regional climate models used for Great Lakes projections either neglected the lake-atmosphere interactions or are only coupled with a 1-D column lake model to represent the lake hydrodynamics. This study presents a Great Lakes climate change projection that has employed the two-way coupling of a regional climate model with a 3-D lake model (GLARM) to resolve 3-D hydrodynamics essential for large …


Utilization Of Bayesian Optimization And Kwn Modeling For Increased Efficiency Of Al‐Sc Precipitation Strengthening, Kyle Deane, Yang Yang, Joseph Licavoli, Vu Nguyen, Santu Rana, Sunil Gupta, Svetha Venkatesh, Paul G. Sanders Jun 2022

Utilization Of Bayesian Optimization And Kwn Modeling For Increased Efficiency Of Al‐Sc Precipitation Strengthening, Kyle Deane, Yang Yang, Joseph Licavoli, Vu Nguyen, Santu Rana, Sunil Gupta, Svetha Venkatesh, Paul G. Sanders

Michigan Tech Publications

The Kampmann and Wagner numerical model was adapted in MATLAB to predict the precipitation and growth of Al3Sc precipitates as a function of starting concentration and heat‐treatment steps. This model was then expanded to predict the strengthening in alloys using calculated average precipitate number density, radius, etc. The calibration of this model was achieved with Bayesian optimization, and the model was verified against experimentally gathered hardness data. An analysis of the outputs from this code allowed the development of optimal heat treatments, which were validated experimentally and proven to result in higher final strengths than were previously observed. Bayesian optimization …


Antimicrobial Mechanisms Of Biomaterials: From Macro To Nano, Shounak Roy, Sanchita Sarkhel, Deepali Bisht, Samerender Nagam Hanumantharao, Smitha Rao, Amit Jaiswal Jun 2022

Antimicrobial Mechanisms Of Biomaterials: From Macro To Nano, Shounak Roy, Sanchita Sarkhel, Deepali Bisht, Samerender Nagam Hanumantharao, Smitha Rao, Amit Jaiswal

Michigan Tech Publications

Overcoming the global concern of antibiotic resistance is one of the biggest challenge faced by scientists today and the key to tackle this issue of emerging infectious diseases is the development of next-generation antimicrobials. The rapid emergence of multi-drug resistant microbes, superbugs and mutated strains of viruses have fueled the search for new and alternate antimicrobial agents with broad-spectrum biocidal activity. Biomaterials, ranging from macroscopic polymers, proteins, and peptides to nanoscale materials such as nanoparticles, nanotubes and nanosheets have emerged as effective antimicrobials. An extensive body of research has established the antibacterial and antiviral efficiencies of different types of biomaterials. …


The Tertiary Sequence Of Varkala Coastal Cliffs, Southwestern India: An Ideal Site For Global Geopark, K. S. Sajinkumar, M. Santosh, V. R. Rani, Subhash Anand, A. P. Pradeepkumar, Anil Chavan, K. P. Thrivikramji, P. V. Ramachandran Jun 2022

The Tertiary Sequence Of Varkala Coastal Cliffs, Southwestern India: An Ideal Site For Global Geopark, K. S. Sajinkumar, M. Santosh, V. R. Rani, Subhash Anand, A. P. Pradeepkumar, Anil Chavan, K. P. Thrivikramji, P. V. Ramachandran

Michigan Tech Publications

Varkala, along the southwestern coast of Peninsular India, has a unique place in Indian geology and geomorphology due to the presence of coastal lateritic cliffs, which exposes the entire Mio-Pliocene sequence of Warkalli Formation, and is declared as the type area. Stratigraphically, this formation exposes carbonaceous clay with lenses of lignite and sticks of marcasite, followed by variegated clays and sandstone. The presence of variegated lithounits endows beauty to these cliffs. Varkala cliffs, edging the Arabian Sea, run for a length of 7.5 km. These cliffs, together with confined beaches, made Varkala a popular tourist destination. Several geodiversity spots within …


The Role Of Regional Connections In Planning For Future Power System Operations Under Climate Extremes, Ana Dyreson, N. Devineni, S. W.D. Turner, T. De Silva M, A. Miara, N. Voisin, S. Cohen, J. Macknick Jun 2022

The Role Of Regional Connections In Planning For Future Power System Operations Under Climate Extremes, Ana Dyreson, N. Devineni, S. W.D. Turner, T. De Silva M, A. Miara, N. Voisin, S. Cohen, J. Macknick

Michigan Tech Publications

Identifying the sensitivity of future power systems to climate extremes must consider the concurrent effects of changing climate and evolving power systems. We investigated the sensitivity of a Western U.S. power system to isolated and combined heat and drought when it has low (5%) and moderate (31%) variable renewable energy shares, representing historic and future systems. We used an electricity operational model combined with a model of historically extreme drought (for hydropower and freshwater-reliant thermoelectric generators) over the Western U.S. and a synthetic, regionally extreme heat event in Southern California (for thermoelectric generators and electricity load). We found that the …


Comparison Of Performance Of Self-Expanding And Balloon-Expandable Transcatheter Aortic Valves, Hoda Hatoum, Milad Samaee, Janarthanan Sathananthan, Stephanie Sellers, Maximilian Kuetting, Scott M. Lilly, Abdul R. Ihdayhid, Philipp Blanke, Jonathon Leipsic, Vinod H. Thourani, Lakshmi Prasad Dasi Jun 2022

Comparison Of Performance Of Self-Expanding And Balloon-Expandable Transcatheter Aortic Valves, Hoda Hatoum, Milad Samaee, Janarthanan Sathananthan, Stephanie Sellers, Maximilian Kuetting, Scott M. Lilly, Abdul R. Ihdayhid, Philipp Blanke, Jonathon Leipsic, Vinod H. Thourani, Lakshmi Prasad Dasi

Michigan Tech Publications

Objective: To evaluate the flow dynamics of self-expanding and balloon-expandable transcatheter aortic valves pertaining to turbulence and pressure recovery. Transcatheter aortic valves are characterized by different designs that have different valve performance and outcomes. Methods: Assessment of transcatheter aortic valves was performed using self-expanding devices (26-mm Evolut [Medtronic], 23-mm Allegra [New Valve Technologies], and small Acurate neo [Boston Scientific]) and a balloon-expandable device (23-mm Sapien 3 [Edwards Lifesciences]). Particle image velocimetry assessed the flow downstream. A Millar catheter was used for pressure recovery calculation. Velocity, Reynolds shear stresses, viscous shear stress, and pressure gradients were calculated. Results: The maximal velocity …


Me-Em Enewsbrief, June 2022, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University Jun 2022

Me-Em Enewsbrief, June 2022, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical Engineering-Engineering Mechanics eNewsBrief

No abstract provided.


Integrating Deep Learning And Hydrodynamic Modeling To Improve The Great Lakes Forecast, Pengfei Xue, Aditya Wagh, Gangfeng Ma, Yilin Wang, Yongchao Yang, Tao Liu, Chenfu Huang May 2022

Integrating Deep Learning And Hydrodynamic Modeling To Improve The Great Lakes Forecast, Pengfei Xue, Aditya Wagh, Gangfeng Ma, Yilin Wang, Yongchao Yang, Tao Liu, Chenfu Huang

Michigan Tech Publications

The Laurentian Great Lakes, one of the world’s largest surface freshwater systems, pose a modeling challenge in seasonal forecast and climate projection. While physics-based hydrodynamic modeling is a fundamental approach, improving the forecast accuracy remains critical. In recent years, machine learning (ML) has quickly emerged in geoscience applications, but its application to the Great Lakes hydrodynamic prediction is still in its early stages. This work is the first one to explore a deep learning approach to predicting spatiotemporal distributions of the lake surface temperature (LST) in the Great Lakes. Our study shows that the Long Short-Term Memory (LSTM) neural network, …


Free-Decay Heave Motion Of A Spherical Buoy, Jacob K. Colling, Saeed Jafari Kang, Esmaeil Dehdashti, Salman Husain, Hassan Masoud, Gordon Parker May 2022

Free-Decay Heave Motion Of A Spherical Buoy, Jacob K. Colling, Saeed Jafari Kang, Esmaeil Dehdashti, Salman Husain, Hassan Masoud, Gordon Parker

Michigan Tech Publications

We examined the heave motion of a spherical buoy during a free-decay drop test. A comprehensive approach was adopted to study the oscillations of the buoy involving experimental measurements and complementary numerical simulations. The experiments were performed in a wave tank equipped with an array of high-speed motion-capture cameras and a set of high-precision wave gauges. The simulations included three sets of calculations with varying levels of sophistication. Specifically, in one set, the volume-of-fluid (VOF) method was used to solve the incompressible, two-phase, Navier–Stokes equations on an overset grid, whereas the calculations in other sets were based on Cummins and …


Virucidal N95 Respirator Face Masks Via Ultrathin Surface-Grafted Quaternary Ammonium Polymer Coatings, Mirco Sorci, Tanner D. Fink, Vaishali Sharma, Sneha Singh, Ruiwen Chen, Brigitte L. Arduini, Katharine Dovidenko, Caryn L. Heldt, Edmund F. Palermo, R Helen Zha May 2022

Virucidal N95 Respirator Face Masks Via Ultrathin Surface-Grafted Quaternary Ammonium Polymer Coatings, Mirco Sorci, Tanner D. Fink, Vaishali Sharma, Sneha Singh, Ruiwen Chen, Brigitte L. Arduini, Katharine Dovidenko, Caryn L. Heldt, Edmund F. Palermo, R Helen Zha

Michigan Tech Publications

N95 respirator face masks serve as effective physical barriers against airborne virus transmission, especially in a hospital setting. However, conventional filtration materials, such as nonwoven polypropylene fibers, have no inherent virucidal activity, and thus, the risk of surface contamination increases with wear time. The ability of face masks to protect against infection can be likely improved by incorporating components that deactivate viruses on contact. We present a facile method for covalently attaching antiviral quaternary ammonium polymers to the fiber surfaces of nonwoven polypropylene fabrics that are commonly used as filtration materials in N95 respirators via ultraviolet (UV)-initiated grafting of biocidal …


Semantic Segmentation To Extract Coronary Arteries In Invasive Coronary Angiograms, Chen Zhao, Robert Bober, Haipeng Ang, Jinshan Tang, Minghao Dong, Chaoyang Zhang, Zhuo He, Weihua Zhou, Et. Al. May 2022

Semantic Segmentation To Extract Coronary Arteries In Invasive Coronary Angiograms, Chen Zhao, Robert Bober, Haipeng Ang, Jinshan Tang, Minghao Dong, Chaoyang Zhang, Zhuo He, Weihua Zhou, Et. Al.

Michigan Tech Publications

Accurate semantic segmentation of each coronary artery using invasive coronary angiography (ICA) is important for stenosis assessment and coronary artery disease (CAD) diagnosis. In this paper, we propose a multi-step semantic segmentation algorithm based on analyzing arterial segments extracted from ICAs. The proposed algorithm firstly extracts the entire arterial binary mask (binary vascular tree) using a deep learning-based method. Then we extract the centerline of the binary vascular tree and separate it into different arterial segments. Finally, by extracting the underlying arterial topology, position, and pixel features, we construct a powerful coronary artery segment classifier based on a support vector …


Non-Reacting Spray Characteristics Of Gasoline And Diesel With A Heavy-Duty Single-Hole Injector, Tom Tzanetakis, Jaclyn Johnson, Henry Schmidt, William Atkinson, Jeffrey Naber May 2022

Non-Reacting Spray Characteristics Of Gasoline And Diesel With A Heavy-Duty Single-Hole Injector, Tom Tzanetakis, Jaclyn Johnson, Henry Schmidt, William Atkinson, Jeffrey Naber

Michigan Tech Publications

Gasoline compression ignition (GCI) is a promising combustion technology that could help alleviate the projected demand for diesel in commercial transport while providing a pathway to achieve upcoming CO2 and criteria pollutant regulations for heavy-duty engines. However, relatively high (i.e., diesel-like) injection pressures are needed to enable GCI across the entire load range while maintaining soot emissions benefits and managing heat release rates. There have only been a limited number of previous studies investigating the spray characteristics of light distillates with high-pressure direct-injection hardware under charge gas conditions relevant to heavy-duty applications. The current work aims to address this issue …


Energy Science & Engineering: 10 Years Of Excellence, Yun Hang Hu May 2022

Energy Science & Engineering: 10 Years Of Excellence, Yun Hang Hu

Michigan Tech Publications

No abstract provided.


Final Inversion Of The Midcontinent Rift During The Rigolet Phase Of The Grenvillian Orogeny, Eben B. Hodgin, Nicholas L. Swanson-Hysell, James M. Degraff, Andrew R.C. Kylander-Clark, Mark D. Schmitz, Andrew C. Turner, Yiming Zhang, Daniel A. Stolper May 2022

Final Inversion Of The Midcontinent Rift During The Rigolet Phase Of The Grenvillian Orogeny, Eben B. Hodgin, Nicholas L. Swanson-Hysell, James M. Degraff, Andrew R.C. Kylander-Clark, Mark D. Schmitz, Andrew C. Turner, Yiming Zhang, Daniel A. Stolper

Michigan Tech Publications

Despite being a prominent continental-scale feature, the late Mesoproterozoic North American Midcontinent Rift did not result in the break-up of Laurentia, and subsequently underwent structural inversion. The timing of inversion is critical for constraining far-field effects of orogenesis and processes associated with the rift’s failure. The Keweenaw fault in northern Michigan (USA) is a major thrust structure associated with rift inversion; it places ca. 1093 Ma rift volcanic rocks atop the post-rift Jacobsville Formation, which is folded in its footwall. Previous detrital zircon (DZ) U-Pb geochronology conducted by laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) assigned a ca. 950 Ma maximum …


Mechanobiology In The Comorbidities Of Ehlers Danlos Syndrome, Shaina P. Royer, Sangyoon J. Han Apr 2022

Mechanobiology In The Comorbidities Of Ehlers Danlos Syndrome, Shaina P. Royer, Sangyoon J. Han

Michigan Tech Publications

Ehlers-Danlos Syndromes (EDSs) are a group of connective tissue disorders, characterized by skin stretchability, joint hypermobility and instability. Mechanically, various tissues from EDS patients exhibit lowered elastic modulus and lowered ultimate strength. This change in mechanics has been associated with EDS symptoms. However, recent evidence points toward a possibility that the comorbidities of EDS could be also associated with reduced tissue stiffness. In this review, we focus on mast cell activation syndrome and impaired wound healing, comorbidities associated with the classical type (cEDS) and the hypermobile type (hEDS), respectively, and discuss potential mechanobiological pathways involved in the comorbidities.


Economic Feasibility Analysis Of Variable-Speed Pumps By Simulating 15 Multiple Water Distribution Systems, Conrad B. Truettner, Brian D. Barkdoll Apr 2022

Economic Feasibility Analysis Of Variable-Speed Pumps By Simulating 15 Multiple Water Distribution Systems, Conrad B. Truettner, Brian D. Barkdoll

Michigan Tech Publications

The UN Sustainability Goals address measures to reduce environmental pollution. Water distribution systems (WDSs) use electric energy, which pollutes the atmosphere through, at least partly, the burning of coal. This study simulates, through modeling, variable-speed pumps (VSPs) on 15 different real WDSs on the network solver EPANET and analyzes the payback period. An algorithm is introduced here to select the optimal pump speed pattern to save the most energy while satisfying the constrain of sufficient pressure at all times and all locations. It was found that five of the 15 systems operated unsuccessfully using a VSP, due to the VSP …


Literature Review On The Discrete Element Method In Asphalt Mixtures, Hui Yao, Mei Xu, Junfu Liu, Yu Liu, Jie Ji, Zhanping You Apr 2022

Literature Review On The Discrete Element Method In Asphalt Mixtures, Hui Yao, Mei Xu, Junfu Liu, Yu Liu, Jie Ji, Zhanping You

Michigan Tech Publications

Asphalt mixtures are commonly used in pavement engineering, especially for highway construction. The mechanism exploration and analysis of pavement distress are the main challenges for researchers and industry managers. Thereby, it is important to understand their properties and interaction mechanisms in asphalt mixtures. It is difficult to conduct some sophisticated or microscale tests in the laboratory, and numerical simulation and virtual tests can be solutions for these cases with low costs. The Discrete Element Method (DEM) is a promising tool for researchers to undertake these tasks. This paper mainly summarized and analyzed the research progress and development prospect of DEMs …


Wave-Optics Investigation Of Branch-Point Density, Jeffrey R. Beck, Jeremy Bos, Terry J. Brennan, Mark F. Spencer Apr 2022

Wave-Optics Investigation Of Branch-Point Density, Jeffrey R. Beck, Jeremy Bos, Terry J. Brennan, Mark F. Spencer

Michigan Tech Publications

We use wave-optics simulations to investigate branch-point density (i.e., the number of branch points within the pupil-phase function) in terms of the grid sampling. The goal for these wave-optics simulations is to model plane-wave propagation through homogeneous turbulence, both with and without the effects of a finite inner scale modeled using a Hill spectrum. In practice, the grid sampling provides a gauge for the amount of branch-point resolution within the wave-optics simulations, whereas the Rytov number, Fried coherence diameter, and isoplanatic angle provide parameters to setup and explore the associated deep-turbulence conditions. Via Monte Carlo averaging, the results show that …


Sources Of Hydrothermal Fluids Inferred From Oxygen And Carbon Isotope Composition Of Calcite, Keweenaw Peninsula Native Copper District, Michigan, Usa, Thomas Bodden, Theodore J. Bornhorst, Florence Bégué, Chad Deering Apr 2022

Sources Of Hydrothermal Fluids Inferred From Oxygen And Carbon Isotope Composition Of Calcite, Keweenaw Peninsula Native Copper District, Michigan, Usa, Thomas Bodden, Theodore J. Bornhorst, Florence Bégué, Chad Deering

Michigan Tech Publications

The Mesoproterozoic North American Midcontinent Rift hosts the world’s largest accu-mulation of native copper in Michigan’s Keweenaw Peninsula. During a regional metamorpho-genic‐hydrothermal event, native copper was deposited along with spatially zoned main‐stage minerals in a thermal high. This was followed by deposition of late‐stage minerals including minor copper sulfide. Inferences from the oxygen and carbon isotopic composition of main‐stage hydrothermal fluids, as calculated from 296 new and compiled isotopic measurements on calcite, are consistent with existing models that low‐sulfur saline native copper ore‐forming fluids were domi-nantly derived by burial metamorphic processes from the very low sulfur basalt‐dominated rift fill at …


A New Stefan Equation To Characterize The Evolution Of Thermokarst Lake And Talik Geometry, Noriaki Ohara, Benjamin M. Jones, Andrew D. Parsekian, Kenneth M Hinkel, Katsu Yamatani, Mikhail Kanevskiy, Rodrigo C. Rangel, Amy L. Breen, Helena Bergstedt Apr 2022

A New Stefan Equation To Characterize The Evolution Of Thermokarst Lake And Talik Geometry, Noriaki Ohara, Benjamin M. Jones, Andrew D. Parsekian, Kenneth M Hinkel, Katsu Yamatani, Mikhail Kanevskiy, Rodrigo C. Rangel, Amy L. Breen, Helena Bergstedt

Michigan Tech Publications

Thermokarst lake dynamics, which play an essential role in carbon release due to permafrost thaw, are affected by various geomorphological processes. In this study, we derive a three-dimensional (3D) Stefan equation to characterize talik geometry under a hypothetical thermokarst lake in the continuous permafrost region. Using the Euler equation in the calculus of variations, the lower bounds of the talik were determined as an extremum of the functional describing the phase boundary area with a fixed total talik volume. We demonstrate that the semi-ellipsoid geometry of the talik is optimal for minimizing the total permafrost thaw under the lake for …


Aeroelastic Response Of Wind Turbine Rotors Under Rapid Actuation Of Flap-Based Flow Control Devices, Muraleekrishnan Menon, Fernando L. Ponta Apr 2022

Aeroelastic Response Of Wind Turbine Rotors Under Rapid Actuation Of Flap-Based Flow Control Devices, Muraleekrishnan Menon, Fernando L. Ponta

Michigan Tech Publications

The largest commercial wind turbines today are rated at powers between 12 MW to 16 MW, with rotor diameters between 220 m to 242 m, which are expected to grow beyond 250 m in the near future. Economies-of-scale factors suggest the advantages of upscaling in rotor size to effectively harvest the wind potential. An increased emphasis on studies related to improvements and innovations in aerodynamic load-control methodologies has led researchers to focus on overcoming the bottlenecks in size upscaling. Though conventional pitch control is an effective approach for long-term load variations, their application to mitigate short-term fluctuations has limitations. This …


Overcoming Supply Disruptions During Pandemics By Utilizing Found Hardware For Open Source Gentle Ventilation, S. Oberloier, N. Gallup, J. M. Pearce Apr 2022

Overcoming Supply Disruptions During Pandemics By Utilizing Found Hardware For Open Source Gentle Ventilation, S. Oberloier, N. Gallup, J. M. Pearce

Michigan Tech Publications

This article details the design of an open source emergency gentle ventilator (gentle-vent) framework that can be used in periods of scarcity. Although it is not a medical device, the system utilizes a wide range of commonly-available components that are combined using basic electronics skills to achieve the desired performance. The main function of the gentle-vent is to generate a calibrated pressure wave at the pump to provide support to the patient's breathing. Each gentle-vent permutation was tested using a DIY manometer as it would be utilized in the field in low-resource settings and validated with an open source VentMon. …


Meteorite Impact Craters As Hotspots For Mineral Resources And Energy Fuels: A Global Review, S. James, Saranya R. Chandran, M. Santosh, A. P. Pradeepkumar, M. N. Praveen, K. S. Sajinkumar Apr 2022

Meteorite Impact Craters As Hotspots For Mineral Resources And Energy Fuels: A Global Review, S. James, Saranya R. Chandran, M. Santosh, A. P. Pradeepkumar, M. N. Praveen, K. S. Sajinkumar

Michigan Tech Publications

The ever-increasing recovery rate of natural resources from terrestrial impact craters over the last few decades across the globe offers new avenues for further exploration of mineral and hydrocarbon resources in such settings. As of today, 60 of the 208 terrestrial craters have been identified to host diverse resources such as hydrocarbons, metals and construction materials. The potential of craters as plausible resource contributors to the energy sector is therefore, worthy of consideration, as 42 (70%) of the 60 craters host energy resources such as oil, gas, coal, uranium, mercury, critical and major minerals as well as hydropower resources. Among …


Remote Sensing For Energy Resources: Introduction, K. S. Sajinkumar, Thomas Oommen Apr 2022

Remote Sensing For Energy Resources: Introduction, K. S. Sajinkumar, Thomas Oommen

Michigan Tech Publications

No abstract provided.


Insar As A Tool For Monitoring Hydropower Projects: A Review, J. Aswathi, R. B. Binoj Kumar, Thomas Oommen, E. H. Bouali, K. S. Sajinkumar Apr 2022

Insar As A Tool For Monitoring Hydropower Projects: A Review, J. Aswathi, R. B. Binoj Kumar, Thomas Oommen, E. H. Bouali, K. S. Sajinkumar

Michigan Tech Publications

This paper provides a review of using Interferometric Synthetic Aperture Radar (InSAR), a microwave remote sensing technique, for deformation monitoring of hydroelectric power projects, a critical infrastructure that requires consistent and reliable monitoring. Almost all major dams around the world were built for the generation of hydropower. InSAR can enhance dam safety by providing timely settlement measurements at high spatial-resolution. This paper provides a holistic view of different InSAR deformation monitoring techniques such as Differential Synthetic Aperture Radar Interferometry (DInSAR), Ground-Based Synthetic Aperture Radar (GBInSAR), Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR), Multi-Temporal Interferometric Synthetic Aperture Radar (MTInSAR), Quasi-Persistent Scatterer …