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Articles 1531 - 1560 of 12164

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Rigidly Foldable Thick Origami Using Designed-Offset Linkages, Robert J. Lang, Nathan Brown, Brian Ignaut, Spencer P. Magleby, Larry L. Howell Mar 2023

Rigidly Foldable Thick Origami Using Designed-Offset Linkages, Robert J. Lang, Nathan Brown, Brian Ignaut, Spencer P. Magleby, Larry L. Howell

Faculty Publications

We present new families of thick origami mechanisms that achieve rigid foldability and parallel stacking of panels in the flat-folded state using linkages for some or all of the hinges between panels. A degree-four vertex results in a multi-loop eight-bar spatial mechanism that can be analyzed as separate linkages. The individual linkages are designed so that they introduce offsets perpendicular to the panels that are mutually compatible around each vertex. This family of mechanisms offers the unique combination of a planar unfolded state, parallel-stacked panels in the flat folded state, and kinematic single-degree-of-freedom motion from the flat- unfolded to the …

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On The Modeling Of A Contact-Aided Cross-Axis Flexural Pivot, Pietro Bilancia, Giovanni Berselli, Spencer P. Magleby, Larry L. Howell Mar 2023

On The Modeling Of A Contact-Aided Cross-Axis Flexural Pivot, Pietro Bilancia, Giovanni Berselli, Spencer P. Magleby, Larry L. Howell

Faculty Publications

This paper reports the study of a planar Cross-Axis Flexural Pivot (CAFP) comprising an additional contact pair. The proposed device turns useful for applications requiring a revolute joint that behaves differently when deflecting clockwise/anti-clockwise. The presence of the contact pair reduces the free length of one flexures, resulting in a considerable increment of the overall joint stiffness. The pivot behaviour is investigated, for different load cases, via the ChainedBeam-Constraint Model (CBCM), namely an accurate method to be applied in large deflection problems. A framework comprising Matlab and ANSYS is developed for testing the CAFP performances in terms of rotational stiffness, …

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A Design Approach To Fully Compliant Multistable Mechanisms Employing A Single Bistable Mechanism, Yanjie Gou, Guimin Chen, Larry L. Howell Mar 2023

A Design Approach To Fully Compliant Multistable Mechanisms Employing A Single Bistable Mechanism, Yanjie Gou, Guimin Chen, Larry L. Howell

Faculty Publications

A fully compliant multistable mechanism is a monolithic structure that is capable of staying at multiple positions without power input, and has many applications including switches, valves, positioners. However, it is difficult to design such a mechanism because of the complexities of the multistable behavior, the practical stress limits and the buckling constraints. This paper discusses the design approach for fully compliant multistable mechanisms which employs a single bistable mechanism and several end-effectors connected in series. The force-displacement characteristics of the end-effectors are derived using the pseudo-rigid-body model. The design approach to the fully compliant multistable mechanism is provided to …

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Kinetostatic And Dynamic Modeling Of Flexure-Based Compliant Mechanisms: A Survey, Mingxiang Ling, Larry L. Howell, Junyi Cao, Guimin Chen Mar 2023

Kinetostatic And Dynamic Modeling Of Flexure-Based Compliant Mechanisms: A Survey, Mingxiang Ling, Larry L. Howell, Junyi Cao, Guimin Chen

Faculty Publications

Flexure-based compliant mechanisms are becoming increasingly promising in precision engineering, robotics and other applications due to the excellent advantages of no friction, no backlash, no wear, and minimal requirement of assembly. Because compliant mechanisms have inherent coupling of kinematic- mechanical behaviors with large deflections and/or complex serial-parallel configurations, the kinetostatic and dynamic analyses are challenging in comparison to their rigid-body counterparts. To address these challenges, a variety of techniques have been reported in a growing stream of publications. This paper surveys and compares the conceptual ideas, key advances, applicable scopes and open problems of the state-of-the-art kinetostatic and dynamic modeling …

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A Cprbm-Based Method For Large-Deflection Analysis Of Contact-Aided Compliant Mechanisms Considering Beam-To-Beam Contacts, Mohui Jin, Benliang Zhu, Jiasi Mo, Zhou Yang, Xianmin Zhang, Larry L. Howell Mar 2023

A Cprbm-Based Method For Large-Deflection Analysis Of Contact-Aided Compliant Mechanisms Considering Beam-To-Beam Contacts, Mohui Jin, Benliang Zhu, Jiasi Mo, Zhou Yang, Xianmin Zhang, Larry L. Howell

Faculty Publications

Contact-aided compliant mechanisms (CCMs) utilize contact to achieve enhanced functionality. The contact phenomenon of CCMs increases the difficulties of their analysis and design, especially when they exhibit beam-to-beam contact. Considering the particularity of CCMs analysis, which is more about the mechanisms’ deformation, this paper presents a numerical method to analyze the large deflection and stress of the CCMs considering beam-to-beam contacts. Based on our previous work on beam-to-rigid contact, the large deformation of general beams in CCMs is modeled by using the chained pseudo-rigid-body model (CPRBM). An approximation based on the geometric information of CPRBM is proposed in this paper …

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An Origami-Based Medical Support System To Mitigate Flexible Shaft Buckling, Brandon Sargent, Jared Butler, Kendall Seymour, David Bailey, Brian D. Jensen, Spencer P. Magleby, Larry L. Howell Mar 2023

An Origami-Based Medical Support System To Mitigate Flexible Shaft Buckling, Brandon Sargent, Jared Butler, Kendall Seymour, David Bailey, Brian D. Jensen, Spencer P. Magleby, Larry L. Howell

Faculty Publications

This paper presents the development of an origami-inspired support system (the OriGuide) that enables the insertion of flexible instruments using medical robots. Varying parameters of a triangulated cylindrical origami pattern were combined to create an effective highly-compressible anti-buckling system that maintains a constant inner diameter for supporting an instrument and a constant outer diameter throughout actuation. The proposed origami pattern is composed of two repeated patterns: a bistable pattern to create support points to mitigate flexible shaft buckling and a monostable pattern to enable axial extension and compression of the support system. The origami-based portion of the device is combined …

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Design Of Regular 1d, 2d, And 3d Linkage-Based Tessellations, Alden D. Yellowhorse, Nathan Brown, Larry L. Howell Mar 2023

Design Of Regular 1d, 2d, And 3d Linkage-Based Tessellations, Alden D. Yellowhorse, Nathan Brown, Larry L. Howell

Faculty Publications

Linkage origami is one effective approach for addressing stiffness and accommodating panels of finite size in origami models and tessellations. However, successfully implementing linkage origami in tessellations can be challenging. In this work, multiple theorems are presented that provide criteria for designing origami units or cells that can be assembled into arbitrarily large tessellations. The application of these theorems is demonstrated through examples of tessellations in two and three dimensions.

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Developable Mechanisms On Right Conical Surfaces, Lance P. Hyatt, Spencer P. Magleby, Larry L. Howell Mar 2023

Developable Mechanisms On Right Conical Surfaces, Lance P. Hyatt, Spencer P. Magleby, Larry L. Howell

Faculty Publications

An approach for designing developable mechanisms on a conical surface is presented. By aligning the joint axes of spherical mechanisms to the ruling lines, the links can be created in a way that the mechanism conforms to a conical surface. Terminology is defined for mechanisms mapped onto a right cone. Models are developed to describe the motion of the mechanism with respect to the apex of the cone, and connections are made to cylindrical developable mechanisms using projected angles. The Loop Sum Method is presented as an approach to determine the geometry of the cone to which a given spherical …

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Deployable Convex Generalized Cylindrical Surfaces Using Torsional Joints, Todd G. Nelson, Jared T. Burton, Curtis G. Nelson, Luis M. Baldelomar Pinto, Zhicheng Deng, Larry L. Howell Mar 2023

Deployable Convex Generalized Cylindrical Surfaces Using Torsional Joints, Todd G. Nelson, Jared T. Burton, Curtis G. Nelson, Luis M. Baldelomar Pinto, Zhicheng Deng, Larry L. Howell

Faculty Publications

The ability to deploy a planar surface to a desired convex profile with a simple actuation can enhance foldable or morphing airfoils, deployable antennae and reflectors, and other applications where a specific profile geometry is desired from a planar sheet. A model using a system of rigid links joined by torsional springs of tailorable stiffness is employed to create an approximate curved surface when two opposing tip loads are applied. A system of equations describing the shape of the surface during deployment is developed. The physical implementation of the model uses compliant torsion bars as the torsion springs. A multidimensional …

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Fast-, Light-Cured Scintillating Plastic For 3d-Printing Applications, Brian G. Frandsen, Michael Febbraro, Thomas Ruland, Theodore W. Stephens, Paul A. Hausladen, Juan J. Manfredi, James E. Bevins Mar 2023

Fast-, Light-Cured Scintillating Plastic For 3d-Printing Applications, Brian G. Frandsen, Michael Febbraro, Thomas Ruland, Theodore W. Stephens, Paul A. Hausladen, Juan J. Manfredi, James E. Bevins

Faculty Publications

Additive manufacturing techniques enable a wide range of possibilities for novel radiation detectors spanning simple to highly complex geometries, multi-material composites, and metamaterials that are either impossible or cost prohibitive to produce using conventional methods. The present work identifies a set of promising formulations of photocurable scintillator resins capable of neutron-gamma pulse shape discrimination (PSD) to support the additive manufacturing of fast neutron detectors. The development of these resins utilizes a step-by-step, trial-and-error approach to identify different monomer and cross-linker combinations that meet the requirements for 3D printing followed by a 2-level factorial parameter study to optimize the radiation detection …

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Heat Set Creases In Polyethylene Terephthalate (Pet) Sheets To Enable Origami-Based Applications, Brandon Sargent, Nathan Brown, Brian D. Jensen, Spencer P. Magleby, William G. Pitt, Larry L. Howell Mar 2023

Heat Set Creases In Polyethylene Terephthalate (Pet) Sheets To Enable Origami-Based Applications, Brandon Sargent, Nathan Brown, Brian D. Jensen, Spencer P. Magleby, William G. Pitt, Larry L. Howell

Faculty Publications

Polyethylene terephthalate (PET) sheets show promise for application in origami-based engineering design. Origami-based engineering provides advantages that are not readily available in traditional engineering design methods. Several processing methods were examined to identify trends and determine the effect of processing of PET sheets on the crease properties of origami mechanisms in PET. Various annealing times, temperatures, and cooling rates were evaluated and data collected for over 1000 samples. It was determined that annealing temperature plays the largest role in crease response. An increase in the crystallinity of a PET sheet while in the folded state likely increases the force response …

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Membrane-Enhanced Lamina Emergent Torsional Joints For Surrogate Folds, Guimin Chen, Spencer P. Magleby, Larry L. Howell Mar 2023

Membrane-Enhanced Lamina Emergent Torsional Joints For Surrogate Folds, Guimin Chen, Spencer P. Magleby, Larry L. Howell

Faculty Publications

Lamina emergent compliant mechanisms (including origami-adapted compliant mechanisms) are mechanical devices that can be fabricated from a planar material (a lamina) and have motion that emerges out of the fabrication plane. Lamina emergent compliant mechanisms often exhibit undesirable parasitic motions due to the planar fabrication constraint. This work introduces a type of lamina emergent torsion (LET) joint that reduces parasitic motions of lamina emergent mechanisms (LEMs), and presents equations for modeling parasitic motion of LET joints. The membrane joint also makes possible one-way joints that can ensure origami-based mechanisms emerge from their flat state (a change point) into the desired …

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Limits Of Extramobile And Intramobile Motion Of Cylindrical Developable Mechanisms, Jared Butler, Larry L. Howell, Spencer P. Magleby, Jacob Greenwood Mar 2023

Limits Of Extramobile And Intramobile Motion Of Cylindrical Developable Mechanisms, Jared Butler, Larry L. Howell, Spencer P. Magleby, Jacob Greenwood

Faculty Publications

Mechanisms that can both deploy and provide motions to perform desired tasks offer a multifunctional advantage over traditional mechanisms. Developable mechanisms (DMs) are devices capable of conforming to a predetermined developable surface and deploying from that surface to achieve specific motions. This paper builds on the previously identified behaviors of extramobility and intramobility by introducing the terminology of extramobile and intramobile motion, which define the motion of developable mechanisms while interior and exterior to a developable surface. The limits of motion are identified using defined conditions. It is shown that the more difficult of these conditions to kinematically predict may …

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Analysis Of The Rigid Motion Of A Conical Developable Mechanism, Mckell Woodland, Michelle Hsiung, Erin L. Matheson, C Alex Safsten, Jacob Greenwood, Denise M. Halverson, Larry L. Howell Mar 2023

Analysis Of The Rigid Motion Of A Conical Developable Mechanism, Mckell Woodland, Michelle Hsiung, Erin L. Matheson, C Alex Safsten, Jacob Greenwood, Denise M. Halverson, Larry L. Howell

Faculty Publications

We demonstrate analytically that it is possible to construct a developable mechanism on a cone that has rigid motion. We solve for the paths of rigid motion and analyze the properties of this motion. In particular, we provide an analytical method for predicting the behavior of the mechanism with respect to the conical surface. Moreover, we observe that the conical developable mechanisms specified in this paper have motion paths that necessarily contain bifurcation points which lead to an unbounded array of motion paths in the parameterization plane.

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Load-Displacement Characterization In Three Degrees Of Freedom For General Let Arrays, Nathan A. Pehrson, Pietro Bilancia, Spencer P. Magleby, Larry L. Howell Mar 2023

Load-Displacement Characterization In Three Degrees Of Freedom For General Let Arrays, Nathan A. Pehrson, Pietro Bilancia, Spencer P. Magleby, Larry L. Howell

Faculty Publications

Lamina emergent torsion (LET) joints for use in origami-based applications enables folding of panels. Placing LET joints in series and parallel (formulating LET arrays) opens the design space to provide for tunable stiffness characteristics in other directions while maintaining the ability to fold. Analytical equations characterizing the elastic load-displacement for general serial-parallel formulations of LET arrays for three degrees of freedom are presented: rotation about the desired axis, in-plane rotation, and extension/compression. These equations enable the design of LET arrays for a variety of applications, including origami-based mechanisms. These general equations are verified using finite element analysis and, to show …

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Nsf/Ieee-Tcpp Curriculum On Parallel And Distributed Computing For Undergraduates - Version Ii - Big Data, Energy, And Distributed Computing, Sushil Prasad, Charles Weems, Alan Sussman, Anshul Gupta, Trilce Estrada, Ramachandran Vaidyanathan, Sheikh Ghafoor, Krishna Kant, Craig Stunkel Mar 2023

Nsf/Ieee-Tcpp Curriculum On Parallel And Distributed Computing For Undergraduates - Version Ii - Big Data, Energy, And Distributed Computing, Sushil Prasad, Charles Weems, Alan Sussman, Anshul Gupta, Trilce Estrada, Ramachandran Vaidyanathan, Sheikh Ghafoor, Krishna Kant, Craig Stunkel

Faculty Publications

This special session will report on the updated NSF/IEEE-TCPP Curriculum on Parallel and Distributed Computing released in Nov 2020 by the Center for Parallel and Distributed Computing Curriculum Development and Educational Resources (CDER). The purpose of the special session is to obtain SIGCSE community feedback on this curriculum in a highly interactive manner employing the hybrid modality and supported by a full-time CDER booth for the duration of SIGCSE. In this era of big data, cloud, and multi- and many-core systems, it is essential that the computer science (CS) and computer engineering (CE) graduates have basic skills in parallel and …

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Autonomous Single-Molecule Manipulation Based On Reinforcement Learning, Bernhard Ramsauer, Grant J. Simpson, Johannes J. Cartus, Andreas Jeindl, Victor García-López, James M. Tour, Leonhard Grill, Oliver T. Hofmann Mar 2023

Autonomous Single-Molecule Manipulation Based On Reinforcement Learning, Bernhard Ramsauer, Grant J. Simpson, Johannes J. Cartus, Andreas Jeindl, Victor García-López, James M. Tour, Leonhard Grill, Oliver T. Hofmann

Faculty Publications

Building nanostructures one-by-one requires precise control of single molecules over many manipulation steps. The ideal scenario for machine learning algorithms is complex, repetitive, and time-consuming. Here, we show a reinforcement learning algorithm that learns how to control a single dipolar molecule in the electric field of a scanning tunneling microscope. Using about 2250 iterations to train, the algorithm learned to manipulate the molecule toward specific positions on the surface. Simultaneously, it generates physical insights into the movement as well as orientation of the molecule, based on the position where the electric field is applied relative to the molecule. This reveals …

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Attochemistry Regulation Of Charge Migration, Aderonke S. Folorunso, François Mauger, Kyle A. Hamer, Denawakage D. Jayasinghe, Imam S. Wahyutama, Justin R. Ragains, Robert R. Jones, Louis F. Dimauro, Mette B. Gaarde, Kenneth J. Schafer, Kenneth Lopata Mar 2023

Attochemistry Regulation Of Charge Migration, Aderonke S. Folorunso, François Mauger, Kyle A. Hamer, Denawakage D. Jayasinghe, Imam S. Wahyutama, Justin R. Ragains, Robert R. Jones, Louis F. Dimauro, Mette B. Gaarde, Kenneth J. Schafer, Kenneth Lopata

Faculty Publications

Charge migration (CM) is a coherent attosecond process that involves the movement of localized holes across a molecule. To determine the relationship between a molecule's structure and the CM dynamics it exhibits, we perform systematic studies of para-functionalized bromobenzene molecules (X-C6H4-R) using real-time time-dependent density functional theory. We initiate valence-electron dynamics by emulating rapid strong-field ionization leading to a localized hole on the bromine atom. The resulting CM, which takes on the order of 1 fs, occurs via an X localized → C6H4delocalized → R localized mechanism. Interestingly, the hole contrast on the acceptor functional group increases with increasing electron-donating …

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Zero Torque Compliant Mechanisms Employing Pre-Buckled Beams, Pietro Bilancia, Samuel Porter Smith, Giovanni Berselli, Spencer P. Magleby, Larry L. Howell Mar 2023

Zero Torque Compliant Mechanisms Employing Pre-Buckled Beams, Pietro Bilancia, Samuel Porter Smith, Giovanni Berselli, Spencer P. Magleby, Larry L. Howell

Faculty Publications

The concept of a statically balanced mechanism with a single rotational degree of freedom is presented. The proposed device achieves static balancing by combining positive stiff- ness elements and negative stiffness elements within a nuclear domain. Two designs are discussed. The first is composed of an Archimedean spiral and two pinned-pinned pre-buckled beams. The overall mechanism is modeled via an analytical approach and the element dimensions are optimized. The optimal configuration is then tested through finite element analysis (FEA). A second approach replaces the spiral beam with elastic custom-shaped spline beams. An FEA optimization is performed to determine the shape …

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Conceptualizing Stable States In Origami-Based Devices Using An Energy Visualization Approach, Jacob Greenwood, Larry L. Howell, Alex Avila, Spencer P. Magleby Mar 2023

Conceptualizing Stable States In Origami-Based Devices Using An Energy Visualization Approach, Jacob Greenwood, Larry L. Howell, Alex Avila, Spencer P. Magleby

Faculty Publications

In many origami-based applications, a device needs to be maintained in one or more fold states. The origami stability integration method (OSIM) presented in this paper pro- vides an approach for graphically combining various techniques to achieve stability. Existing stability techniques are also categorized into four groups based on whether they are intrinsic or extrinsic to the origami pattern and whether they exhibit gradual or non-gradual energy storage behaviors. These categorizations can help designers select appropriate techniques for their applications. The paper also contains de- sign considerations and resources for achieving stability. Finally, two case studies are presented that use …

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Bipolar Membrane Electrodialysis For Sustainable Utilization Of Inorganic Salts From The Reverse Osmosis Concentration Of Real Landfill Leachate, Hao-Ran Yang, Chi-Qian Zhang, Bing Li, Jia-Cheng Yang, Yu-Ming Zheng, Mohammad Younas, Zhi-Hua Zheng Mar 2023

Bipolar Membrane Electrodialysis For Sustainable Utilization Of Inorganic Salts From The Reverse Osmosis Concentration Of Real Landfill Leachate, Hao-Ran Yang, Chi-Qian Zhang, Bing Li, Jia-Cheng Yang, Yu-Ming Zheng, Mohammad Younas, Zhi-Hua Zheng

Faculty Publications

Developing an effective resource utilization method for landfill leachate reverse osmosis concentrate (LLRC) remains a challenge because of the high concentrations of inorganic salts and refractory organic compounds. This study applied a bipolar membrane electrodialysis (BMED) to separate inorganic salts from real LLRC while simultaneously reclaiming inorganic acids and bases. The performance of BMED was affected by operating parameters, such as operating voltage, membrane surface flow velocity, and initial acid-base concentration. With optimized operating parameters, the reclaimed acid-base concentrations, desalination rate, and current efficiency were higher with less energy consumption. Ultimately, 0.41 mol/L acids and 0.40 mol/L bases were reclaimed …

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Temporal Variability In Soil Organic Matter Accretion Rates In Coastal Deltaic Wetlands Under Changing Depositional Environments, Yadav Sapkota, Kehui Xu, Kanchan Maiti, Patrick Inglett, John R. White Mar 2023

Temporal Variability In Soil Organic Matter Accretion Rates In Coastal Deltaic Wetlands Under Changing Depositional Environments, Yadav Sapkota, Kehui Xu, Kanchan Maiti, Patrick Inglett, John R. White

Faculty Publications

The Mississippi River Deltaic Plain experiences high relative sea level rise, limited sediment supply, and high marsh edge erosion, leading to the substantial coastal wetland and stored soil organic matter (SOM) loss. The objective of this study was to understand the SOM accumulation rates over the past 1000 years related to the changes in the depositional environment in these highly eroding coastal wetlands. Soil cores (2 m) were collected from four sites in Barataria Basin, LA and analyzed for proportion of organic and mineral matter, total C, N, P, particle size, and stable isotopic composition (δ13C and δ …

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What Are The Most Effective Proxies In Identifying Storm-Surge Deposits In Paleotempestology? A Quantitative Evaluation From The Sand-Limited, Peat-Dominated Environment Of The Florida Coastal Everglades, Qiang Yao, Kam Biu Liu, Zhenqing Zhang, Erika Rodrigues, Marcelo Cohen, Kanchan Maiti, Yang Yang Mar 2023

What Are The Most Effective Proxies In Identifying Storm-Surge Deposits In Paleotempestology? A Quantitative Evaluation From The Sand-Limited, Peat-Dominated Environment Of The Florida Coastal Everglades, Qiang Yao, Kam Biu Liu, Zhenqing Zhang, Erika Rodrigues, Marcelo Cohen, Kanchan Maiti, Yang Yang

Faculty Publications

Although many studies have attempted to reconstruct millennial-scale hurricane patterns using various proxy-based methods, it is still unclear what the most effective proxies are to identify storm surge deposits in different environmental settings. This study quantitatively compares the application of grain-size, loss-on-ignition, stable isotopes, X-ray fluorescence, and palynological proxies in paleotempestology from an organic-rich environment in the Florida Everglades. The nonparametric tests indicate that only 9 among the 27 parameters (mean diameter, %water, %organic, %carbonate, Ca, Sr, Ca/Ti, Cl/Br, and marine microfossils) exhibited significant differences between storm-surge and in situ deposits. The principal component analysis shows that five marine indicators …

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Stratification Breakdown By Fall Cold Front Winds Over The Louisiana Shelf In The Northern Gulf Of Mexico: A Numerical Experiment, Mohammad Nabi Allahdadi, Chunyan Li, Nazanin Chaichitehrani Mar 2023

Stratification Breakdown By Fall Cold Front Winds Over The Louisiana Shelf In The Northern Gulf Of Mexico: A Numerical Experiment, Mohammad Nabi Allahdadi, Chunyan Li, Nazanin Chaichitehrani

Faculty Publications

Cold fronts are meteorological phenomena that impact the northern Gulf of Mexico, mostly between the fall and spring seasons. On average, they pass the region every 3–7 days, with a duration ranging between 24 and 74 h. In the present study, a high-resolution FVCOM model with an unstructured mesh was used to simulate the effect of the fall cold front winds on water column mixing over the Louisiana shelf, which is often stratified in the summer, leading to hypoxia. Numerical experiments were conducted for October 2009, a period with five consecutive cold front events. Winds from an offshore station forced …

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Multi-Agent Optimal Control For Central Chiller Plants Using Reinforcement Learning And Game Theory, Shunian Qiu, Zhenhai Li, Zhihong Pang, Zhengwei Li, Yinying Tao Mar 2023

Multi-Agent Optimal Control For Central Chiller Plants Using Reinforcement Learning And Game Theory, Shunian Qiu, Zhenhai Li, Zhihong Pang, Zhengwei Li, Yinying Tao

Faculty Publications

To conserve building energy, optimal operation of a building’s energy systems, especially heating, ventilation and air-conditioning (HVAC) systems, is important. This study focuses on the optimization of the central chiller plant, which accounts for a large portion of the HVAC system’s energy consumption. Classic optimal control methods for central chiller plants are mostly based on system performance models which takes much effort and cost to establish. In addition, inevitable model error could cause control risk to the applied system. To mitigate the model dependency of HVAC optimal control, reinforcement learning (RL) algorithms have been drawing attention in the HVAC control …

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Recovery Of Aconitic Acid From Sweet Sorghum Plant Extract Using A Solvent Mixture, And Its Potential Use As A Nematicide, K. Thomas Klasson, Yunci Qi, Gillian O. Bruni, Tristan T. Watson, Bretlyn T. Pancio, Evan Terrell Mar 2023

Recovery Of Aconitic Acid From Sweet Sorghum Plant Extract Using A Solvent Mixture, And Its Potential Use As A Nematicide, K. Thomas Klasson, Yunci Qi, Gillian O. Bruni, Tristan T. Watson, Bretlyn T. Pancio, Evan Terrell

Faculty Publications

Trans-aconitic acid (TAA) is naturally present in sweet sorghum juice and syrup, and it has been promoted as a potential biocontrol agent for nematodes. Therefore, we developed a process for the extraction of aconitic acid from sweet sorghum syrup. The process economics were evaluated, and the extract was tested for its capability to suppress the motility of the nematodes Caenorhabditis elegans and Meloidogyne incognita. Aconitic acid could be efficiently extracted from sweet sorghum syrup using acetone:butanol:ethanol mixtures, and it could be recovered from this solvent with a sodium carbonate solution, with an overall extraction and recovery efficiency of 86%. The …

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Field Applications Of Zein As A Precise Nanoscale Delivery System For Methoxyfenozide, C. A.R. Bonser, C. Tamez, J. C. White, C. E. Astete, C. M. Sabliov, J. A. Davis Mar 2023

Field Applications Of Zein As A Precise Nanoscale Delivery System For Methoxyfenozide, C. A.R. Bonser, C. Tamez, J. C. White, C. E. Astete, C. M. Sabliov, J. A. Davis

Faculty Publications

When insecticides are applied in the environment, much of the product does not reach the target pest. Biopolymeric nanoparticles as nanocarriers have the potential to improve insecticide efficacy by improving absorption, coverage, and permeability while protecting the insecticide active ingredient from abiotic conditions and extending efficacy through controlled release. We conducted a series of experiments using a biopolymeric nanoparticle synthesized from zein, a biodegradable maize protein, to compare efficacy of a nanodelivered hydrophobic insect growth regulator (methoxyfenozide) against a commercial formulation. Positively charged zein nanoparticles (empty and loaded with methoxyfenozide) were compared to the formulated product, Intrepid 2F, as a …

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Recent Advances And Challenges In Implementing Ipm Programmes In The Entomological Context Of Indian Agriculture, Ruchika Geedi, Gadi V.P. Reddy Mar 2023

Recent Advances And Challenges In Implementing Ipm Programmes In The Entomological Context Of Indian Agriculture, Ruchika Geedi, Gadi V.P. Reddy

Faculty Publications

Integrated pest management (IPM) programmes are based on using multiple methods to maintain nuisance insects below tolerant levels in crop fields. Recent advances in IPM in developed countries have incorporated biological pesticides, microbial products, semiochemicals, and beneficial insects, but few of such programmes have been successfully implemented in developing countries, such as India. Semiochemicals play critical roles as signals in various interspecific and intraspecific interactions between insects and plants, and among interacting insects, plants, and microbes. In India IPM programmes have included mechanical, chemical, cultural, and biological management strategies. However, among these methods, biological management has its own limitations. Indian …

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Initial Assessment Of The Toxicologic Effects Of Leachates From 3-Dimensional (3-D) Printed Objects On Sperm Quality In Two Model Fish Species, Matthew J. Schwing, Yue Liu, Jorge A. Belgodere, William T. Monroe, Terrence R. Tiersch, Ahmed Abdelmoneim Mar 2023

Initial Assessment Of The Toxicologic Effects Of Leachates From 3-Dimensional (3-D) Printed Objects On Sperm Quality In Two Model Fish Species, Matthew J. Schwing, Yue Liu, Jorge A. Belgodere, William T. Monroe, Terrence R. Tiersch, Ahmed Abdelmoneim

Faculty Publications

The use of 3-dimensional (3-D) printing is gaining popularity in life sciences and driving innovation in fields including aquatic sperm cryopreservation. Yet, little is known about the effects leachates from these objects may have on biological systems. In this study, we investigated if exposure to leachates from 3-D printed objects fabricated from different photo-curable resins could affect sperm quality in two model fish species, zebrafish (Danio rerio) and goldfish (Carassius auratus). Leachates were collected following contact periods of 10 min and 22 h with objects manufactured using a mask LCD resin printer and three different commercially available resins (i.e., standard, …

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A Fracture Multiscale Model For Peridynamic Enrichment Within The Partition Of Unity Method, Matthias Birner, Patrick Diehl, Robert Lipton, Marc Alexander Schweitzer Mar 2023

A Fracture Multiscale Model For Peridynamic Enrichment Within The Partition Of Unity Method, Matthias Birner, Patrick Diehl, Robert Lipton, Marc Alexander Schweitzer

Faculty Publications

Partition of unity methods are of domain decomposition type and provide the opportunity for multiscale and multiphysics numerical modeling. Different physical models can exist within a partition of unity method scheme for handling problems with zones of linear elasticity and zones where fractures occur. Here, the peridynamic model is used in regions of fracture and smooth partition of unity methods is used in the surrounding linear elastic media. Our method is novel in that we evolve the crack path using peridynamics and apply the partition of unity method to compute the elastic fields in the neighborhood of the crack tip. …

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