Two-Dimensional Scalar Differential Equations For Transversely Varying Thickness Modes In Piezoelectric Plates And Applications In Acoustic Wave Resonator Sensors,
2014
University of Nebraska-Lincoln
Two-Dimensional Scalar Differential Equations For Transversely Varying Thickness Modes In Piezoelectric Plates And Applications In Acoustic Wave Resonator Sensors, Huijing He
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Generalizations are made for three types of well-known and widely used twodimensional scalar differential equations in the literature describing transversely varying thickness modes in piezoelectric plate resonators. They are for singly-rotated quartz plates, doubly-rotated quartz plates, and plates of crystals of class 6mm with the c-axis along the plate thickness, respectively. The purpose of the generalizations is to include the effects of surface mechanical loads such as mass layers or fluids for resonator -based acoustic wave sensor applications. Surface acoustic impedance is introduced to take into account various surface loads in a general manner for time-harmonic motions. Both unelectroded and …
Modular And Cooperative Medical Devices And Related Systems And Methods,
2014
Lincoln, NE
Modular And Cooperative Medical Devices And Related Systems And Methods, Shane M. Farritor, Mark Rentschler, Amy Lehman
Department of Mechanical and Materials Engineering: Faculty Publications
The various embodiments disclosed herein relate to modular medical devices, including various devices with detachable modular components and various devices with pivotally attached modular components. Additional embodiments relate to procedures in which various of the devices are used cooperatively. Certain embodiments of the medical devices are robotic in vivo devices.
Lightweight Uav Launcher,
2014
California Polytechnic State University - San Luis Obispo
Lightweight Uav Launcher, Ben Miller, Christian Valoria, Corinne Warnock, Jake Coutlee
Mechanical Engineering
This report discusses the design, construction, and testing of a lightweight, portable UAV launcher. There is a current need for a small team of soldiers to launch a US Marine Tier II UAV in a remote location without transport. Research was conducted into existing UAV launcher designs and the pros and cons of each were recorded. This research served as a basis for concept generation during the initial design development stage. It was required that the design weigh less than 110 lbs, occupy a smaller volume than 48" x 24" 18" in its collapsed state, be portable by a single …
Detecting Rule Of Balance In Photography,
2014
Portland State University
Detecting Rule Of Balance In Photography, Uyen T. Mai, Feng Liu
Student Research Symposium
Rule of Balance is one of the most important composition rules in photography, which can be used as a standard for photo quality assessment. The rule of balance states that images with evenly distributed visual elements are visually pleasing and thus are highly aesthetic. This work presents a method to automatically classify balanced and unbalanced images. Detecting the rule of balance requires a robust technique to locate and analyze important objects and visual elements, which involves understanding of the image content. Since semantic understanding is currently beyond the state of the art in computer vision, we employ the saliency maps …
Waste Heat Reclamation For Commercial Use,
2014
California Polytechnic State University - San Luis Obispo
Waste Heat Reclamation For Commercial Use, Andrew Webber
Liberal Arts and Engineering Studies
The purpose of this project was to capture waste heat to raise the temperature of groundwater for commercial applications.
Passive Biaxial Mechanical Properties And In Vivo Axial Pre-Stretch Of The Diseased Human Femoropopliteal And Tibial Arteries,
2014
University of Nebraska Medical Center
Passive Biaxial Mechanical Properties And In Vivo Axial Pre-Stretch Of The Diseased Human Femoropopliteal And Tibial Arteries, Alexey Kamenskiy, Iraklis I. Pipinos, Yuris A. Dzenis, Clay Lomneth, Syed A. Jaffar Kazmi, Nicholas Y. Phillips, Jason N. Mactaggart
Department of Mechanical and Materials Engineering: Faculty Publications
Surgical and interventional therapies for atherosclerotic lesions of the infrainguinal arteries are notorious for high rates of failure. Frequently, this leads to expensive reinterventions, return of disabling symptoms, or limb loss. Interaction between the artery and repair material likely plays an important role in reconstruction failure, but data describing the mechanical properties and functional characteristics of human femoropopliteal and tibial arteries are currently not available. Diseased superficial femoral (SFA, n=10), popliteal (PA, n=8), and tibial arteries (TA, n=3) from 10 patients with critical limb ischemia were tested to determine passive mechanical properties using planar biaxial extension. All …
Methods, Systems, And Devices For Surgical Access And Inserton,
2014
University of Nebraska - Lincoln
Methods, Systems, And Devices For Surgical Access And Inserton, Tom Frederick, Shane Farritor, Jack Mondry, Eric Markvicka, Dmitry Oleynikov, Jacob Greenburg
Department of Mechanical and Materials Engineering: Faculty Publications
The various embodiments herein relate to systems, devices, and/or methods relating to Surgical procedures, and more specifically for accessing an insufflated cavity of a patient and/or positioning Surgical systems or devices into the cavity.
Systemand Method For Controlling Motion Of Spacecrafts,
2014
University of Nebraska - Lincoln
Systemand Method For Controlling Motion Of Spacecrafts, Piyush Grover, Christian Andersson
Department of Mechanical and Materials Engineering: Faculty Publications
A motion of an object is controlled from a geostationary transit orbit (GTO) of an earth to an orbit of a moon. A first trajectory of the motion of the object is determined from an intermediate orbit of an earth to a neighborhood of a stable manifold of a first Lagrange point (L1). A second trajectory of the motion of the object is determined from the GTO to the intermediate orbit. A third trajectory of the motion of the object is determined from the neighborhood to the stable manifold to an L1 orbit, and a fourth trajectory of the motion …
Quality And Safety Of Minimally Invasive Surgery: Past, Present, And Future,
2014
University of Nebraska-Lincoln
Quality And Safety Of Minimally Invasive Surgery: Past, Present, And Future, Bernadette Mccrory, Chad A. Lagrange, M. S. Hallbeck
Department of Mechanical and Materials Engineering: Faculty Publications
Adverse events because of medical errors are a leading cause of death in the United States (US) exceeding the mortality rates of motor vehicle accidents, breast cancer, and AIDS. Improvements can and should be made to reduce the rates of preventable surgical errors because they account for nearly half of all adverse events within hospitals. Although minimally invasive surgery (MIS) has proven patient benefits such as reduced postoperative pain and hospital stay, its operative environment imposes substantial physical and cognitive strain on the surgeon increasing the risk of error. To mitigate errors and protect patients, a multidisciplinary approach is needed …
Measurement Of Hydrodynamic Force Generation By Swimming
Dolphins Using Bubble Dpiv,
2014
West Chester University
Measurement Of Hydrodynamic Force Generation By Swimming Dolphins Using Bubble Dpiv, Frank E. Fish, Paul Legac, Terrie M. Williams, Timothy Wei
Department of Mechanical and Materials Engineering: Faculty Publications
Attempts to measure the propulsive forces produced by swimming dolphins have been limited. Previous uses of computational hydrodynamic models and gliding experiments have provided estimates of thrust production by dolphins, but these were indirect tests that relied on various assumptions. The thrust produced by two actively swimming bottlenose dolphins (Tursiops truncatus) was directly measured using digital particle image velocimetry (DPIV). For dolphins swimming in a large outdoor pool, the DPIV method used illuminated microbubbles that were generated in a narrow sheet from a finely porous hose and a compressed air source. The movement of the bubbles was tracked …
Dynamic Fracture Analysis Of Polycarbonate By The Optical Method
Of Caustics,
2014
Peking University
Dynamic Fracture Analysis Of Polycarbonate By The Optical Method Of Caustics, Guiyun Gao, Zheng Li, Mehrdad Negahban
Department of Mechanical and Materials Engineering: Faculty Publications
Glassy polycarbonate (PC) is a widely used engineering material in industries, since it has high strength and toughness as well as good transparency. However, these advantages of PC can be suppressed by physical aging, especially its dynamic fracture toughness. In addition, the material properties of PC can be changed dramatically after large plastic compressive deformation, and it can show obvious orthotropic behavior. Here, the combined effect of aging and plastic compressive deformation on dynamic facture of PC was investigated by the optical method of caustics. The dynamic reflective method of caustics for orthotropic materials was developed here to study the …
Qualifying Composition Dependent P And N Self-Doping In Ch3Nh3Pbi3,
2014
University of Nebraska-Lincoln
Qualifying Composition Dependent P And N Self-Doping In Ch3Nh3Pbi3, Qi Wang, Yuchuan Shao, Haipeng Xie, Lu Lyu, Xiaoliang Liu, Yongli Gao, Jinsong Huang
Department of Mechanical and Materials Engineering: Faculty Publications
We report the observation of self-doping in perovskite. CH3NH3PbI3 was found to be either n- or p-doped by changing the ratio of methylammonium halide (MAI) and lead iodine (PbI2) which are the two precursors for perovskite formation. MAI-rich and PbI2-rich perovskite films are p and n self-doped, respectively. Thermal annealing can convert the p-type perovskite to n-type by removing MAI. The carrier concentration varied as much as six orders of magnitude. A clear correlation between doping level and device performance was also observed.
Polymer Aggregation Correlated Transition From Schottky-Junction To Bulk Heterojunction Organic Solar Cells,
2014
University of Nebraska–Lincoln
Polymer Aggregation Correlated Transition From Schottky-Junction To Bulk Heterojunction Organic Solar Cells, Bin Yang, Zhengguo Xiao, Jinsong Huang
Department of Mechanical and Materials Engineering: Faculty Publications
The fullerene-based organic Schottky-junction solar cells have recently attracted intensive research interest because of their unique electrical performance, such as significant photocurrent generation from excitons created in fullerenes and large open-circuit voltage (VOC) output induced by high Schottky-barrier height between the anode and the fullerene acceptor. This manuscript reports another remarkably appealing advantage that the fullerene-based Schottky-junction solar cells are more stable than the bulk heterojunction counterparts. The better stability is likely due to mitigative polymer photo-oxidation and/or little morphological change of active film in the aged Schottky-junction devices. The transition from Schottky-junction to bulk heterojunction appears at …
Phase Transitions In Mechanically Milled Mn-Al-C Permanent Magnets,
2014
University of Nebraska-Lincoln
Phase Transitions In Mechanically Milled Mn-Al-C Permanent Magnets, Michael J. Lucis, Timothy E. Prost, Xiujuan Jiang, Meiyu Wang, Jeffrey E. Shield
Department of Mechanical and Materials Engineering: Faculty Publications
Mn-Al powders were prepared by rapid solidification followed by high-energy mechanical milling. The rapid solidification resulted in single-phase ε. The milling was performed in both the ε phase and the τ phase, with the τ-phase formation accomplished through a heat treatment at 500 °C for 10 min. For the ε-milled samples, the conversion of the ε to the τ phase was accomplished after milling via the same heat treatment. Mechanical milling induced a significant increase in coercivity in both cases, reaching 4.5 kOe and 4.1 kOe, respectively, followed by a decrease upon further milling. The increase in coercivity was the …
Biomechanical Strain As A Trigger For Pore Formation In
Schlemm’S Canal Endothelial Cells,
2014
Imperial College London
Biomechanical Strain As A Trigger For Pore Formation In Schlemm’S Canal Endothelial Cells, Sietse T. Braakman, Ryan M. Pedrigi, A. Thomas Read, James A. E. Smith, W. Daniel Stamer, C. Ross Ethier, Darryl R. Overby
Department of Mechanical and Materials Engineering: Faculty Publications
The bulk of aqueous humor passing through the conventional outflow pathway must cross the inner wall endothelium of Schlemm’s canal (SC), likely through micron-sized transendothelial pores. SC pore density is reduced in glaucoma, possibly contributing to obstructed aqueous humor outflow and elevated intraocular pressure (IOP). Little is known about the mechanisms of pore formation; however, pores are often observed near dome-like cellular outpouchings known as giant vacuoles (GVs) where significant biomechanical strain acts on SC cells. We hypothesize that biomechanical strain triggers pore formation in SC cells. To test this hypothesis, primary human SC cells were isolated from three non-glaucomatous …
Altered Mechanobiology Of Schlemm’S Canal
Endothelial Cells In Glaucoma,
2014
Imperial College London
Altered Mechanobiology Of Schlemm’S Canal Endothelial Cells In Glaucoma, Darryl R. Overby, Enhua H. Zhou, Rocio Vargas-Pinto, Ryan M. Pedrigi, Rudolf Fuchshofer, Sietse T. Braakman, Ritika Gupta, Kristin M. Perkumas, Joesph M. Sherwood, Amir Vahabikashi, Quynh Dang, Jae Hun Kim, C. Ross Ethier, W. Daniel Stamer, Jeffrey J. Fredberg, Mark Johnson
Department of Mechanical and Materials Engineering: Faculty Publications
Increased flow resistance is responsible for the elevated intraocular pressure characteristic of glaucoma, but the cause of this resistance increase is not known. We tested the hypothesis that altered biomechanical behavior of Schlemm’s canal (SC) cells contributes to this dysfunction. We used atomic force microscopy, optical magnetic twisting cytometry, and a unique cell perfusion apparatus to examine cultured endothelial cells isolated from the inner wall of SC of healthy and glaucomatous human eyes. Here we establish the existence of a reduced tendency for pore formation in the glaucomatous SC cell—likely accounting for increased outflow resistance—that positively correlates with elevated subcortical …
Arising Applications Of Ferroelectric Materials In
Photovoltaic Devices,
2014
University of Nebraska-Lincoln
Arising Applications Of Ferroelectric Materials In Photovoltaic Devices, Yongbo Yuan, Zhengguo Xiao, Bin Yang, Jinsong Huang
Department of Mechanical and Materials Engineering: Faculty Publications
The ferroelectric-photovoltaic (FE-PV) device, in which a homogeneous ferroelectric material is used as a light absorbing layer, has been investigated during the past several decades with numerous ferroelectric oxides. The FE-PV effect is distinctly different from the typical photovoltaic (PV) effect in semiconductor p–n junctions in that the polarization electric field is the driving force for the photocurrent in FE-PV devices. In addition, the anomalous photovoltaic effect, in which the voltage output along the polarization direction can be significantly larger than the bandgap of the ferroelectric materials, has been frequently observed in FE-PV devices. However, a big challenge faced by …
Electrospinning Applications Air Filtration And Superhydrophobic Materials,
2014
VCU
Electrospinning Applications Air Filtration And Superhydrophobic Materials, Negar Ghochaghi, Adetoun Taiwo
Graduate Research Posters
Electrospinning is a widely applicable technique that generates non-woven fibers in the micro and nano range. In this project two of its applications are highlighted namely filtration media and enhancement of wettability. The first project demonstrates that electrospinning can be used to produce new fiber filtration media with controlled microstructure. The bimodal and unimodal orthogonal and random filters were made and characterized against their filtration efficiency and pressure drop. Figure of Merit (FOM) was also calculated and discussed. It is shown that the FOM increases when the electrospun fibers are arranged into alternating layers of aligned course and fine fibers. …
Mode I Fracture Toughness Of Eight-Harness-Satin Carbon Cloth Weaves For Co-Cured And Post-Bonded Laminates,
2013
California Polytechnic State University, San Luis Obispo
Mode I Fracture Toughness Of Eight-Harness-Satin Carbon Cloth Weaves For Co-Cured And Post-Bonded Laminates, Josh E. Smith
Master's Theses
Mode I interlaminar fracture of 3k 8-Harness-Satin Carbon cloth, with identical fill and weft yarns, pre-impregnated with Newport 307 resin was investigated through the DCB test (ASTM D5528). Crack propagations along both the fill and weft yarns were considered for both post-bonded (co-bonded) and co-cured laminates. A patent-pending delamination insertion method was compared to the standard Teflon film option to assess its applicability to mode I fracture testing. The Modified Beam Theory, Compliance Calibration method, and Modified Compliance Calibration method were used for comparative purposes for these investigations and to evaluate the validity of the proposed Equivalent Stiffness (EQS) method. …
Ergonomichandle And Articulating Laparoscopictool,
2013
Lincoln, NE
Ergonomichandle And Articulating Laparoscopictool, M. Susan Hallbeck, Dmitry Oleynikov, Kathryn Done, Tim Judkins, Allison Dimartino, Jonathan Morse, Lawton N. Verner
Department of Mechanical and Materials Engineering: Faculty Publications
The present invention relates to a laparoscopic apparatus. The apparatus includes a handle having a body portion, a top surface, opposite bottom surface, a proximal and distal end. The top surface of the base is contoured to compliment the natural curve of the palm. The apparatus further includes a shaft projecting from the distal end of the handle. The shaft has a proximal and distal end. A control sphere is located on the handle. The control sphere can be moved by one or more of a user's fingers to indicate direction. An end effector is located at the distal end …
