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Cytoplasmic Dynein Binding, Run Length, And Velocity Are Guided By Long-Range Electrostatic Interactions, Lin Li, Joshua Alper, Emil Alexov Aug 2016

Cytoplasmic Dynein Binding, Run Length, And Velocity Are Guided By Long-Range Electrostatic Interactions, Lin Li, Joshua Alper, Emil Alexov

Publications

Dyneins are important molecular motors involved in many essential biological processes, including cargo transport along microtubules, mitosis, and in cilia. Dynein motility involves the coupling of microtubule binding and unbinding to a change in the configuration of the linker domain induced by ATP hydrolysis, which occur some 25 nm apart. This leaves the accuracy of dynein stepping relatively inaccurate and susceptible to thermal noise. Using multi-scale modeling with a computational focusing technique, we demonstrate that the microtubule forms an electrostatic funnel that guides the dynein’s microtubule binding domain (MTBD) as it finally docks to the precise, keyed binding location on …

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Current Sheet Flapping Motions In The Tailwind Flow Of Magnetic Reconnection, Mingyu Wu, Quanming Lu, Martin Volwerk, Zoltán Vörös, Xuanye Ma, Shui Wang Aug 2016

Current Sheet Flapping Motions In The Tailwind Flow Of Magnetic Reconnection, Mingyu Wu, Quanming Lu, Martin Volwerk, Zoltán Vörös, Xuanye Ma, Shui Wang

Publications

The feature and origin of current sheet flapping motions are one of most interesting issues of magnetospheric dynamics. In this paper we report the flapping motion of the current sheet detected in the tailward flow of a magnetic reconnection event on 7 February 2009. This flapping motion with frequency about 12 mHz was accompanied by magnetic turbulence. The observations by the tail‐elongated fleet of five Time History of Events and Macroscale Interactions during Substorms probes indicate that these flapping oscillations were rather confined within the tailward flow than were due to a global process. This flapping motion could be due …

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Completeness Of The Nearby White Dwarf Sample: Let Us Count The Ways, Terry D. Oswalt, Jay Holberg, Edward M. Sion Jul 2016

Completeness Of The Nearby White Dwarf Sample: Let Us Count The Ways, Terry D. Oswalt, Jay Holberg, Edward M. Sion

Publications

We have recently extended our ongoing survey of the local white dwarf population, effectively doubling the sample volume. Based upon the latest distance determinations, Holberg et al. (2016) estimated the present 20 pc and 25 pc samples were about 86 and 68 percent complete, respectively. Here we examine how the completeness of the 25 pc sample depends upon other observables such as apparent magnitude, proper motion, photometric color index, etc. The results may provide additional clues to why “Sirius-Like systems” are underrepresented in the extended 25 pc sample and how additional nearby single white dwarf stars may be found.

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The Influence Of Model Resolution On The Simulated Sensitivity Of North Atlantic Tropical Cyclone Maximum Intensity To Sea Surface Temperature, Sarah Strazzo, James Elsner, Timothy Larow, Hiroyuki Murakami, Michael Wehner, Ming Zhao Jul 2016

The Influence Of Model Resolution On The Simulated Sensitivity Of North Atlantic Tropical Cyclone Maximum Intensity To Sea Surface Temperature, Sarah Strazzo, James Elsner, Timothy Larow, Hiroyuki Murakami, Michael Wehner, Ming Zhao

Publications

No abstract provided.

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Passenger Obesity And Regional Aircraft Performance For The Most Corpulent States In The Usa, Douglas D. Boyd Jul 2016

Passenger Obesity And Regional Aircraft Performance For The Most Corpulent States In The Usa, Douglas D. Boyd

Publications

Obesity affects over 25% of Americans; however, prescribed FAA standard passenger weights for US airlines are based on data compiled 15 years ago. Since increased passenger weight degrades aircraft performance and may lead to a loss of control, the hypothesis herein is that passenger weight under-estimation for states with high obesity rates could potentially lead to a runway overrun or the inability to out climb rising terrain. In terms of the employed methodology, current person weights for the ten most obese states were determined using nationwide data adjusted for state ethnicity. Performance degradation for regional aircraft was assessed by accelerate-stop …

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An Active-Learning Approach To Teaching Tough Topics: Personal Jurisdiction As An Example, Cynthia M. Ho, Angela Upchurch, Susan Gilles Jul 2016

An Active-Learning Approach To Teaching Tough Topics: Personal Jurisdiction As An Example, Cynthia M. Ho, Angela Upchurch, Susan Gilles

Publications

No abstract provided.

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Growth Of Unsteady Wave Groups By Shear Flows, Shahrdad Sajjadi, Julian Hunt, Frederique Drullion Jul 2016

Growth Of Unsteady Wave Groups By Shear Flows, Shahrdad Sajjadi, Julian Hunt, Frederique Drullion

Publications

A weakly nonlinear theory has been proposed and developed for calculating the energy- transfer rate to individual waves in a group. It is shown what portion of total energy- transfer rate, over the envelope of wave group, affects individual waves in the group. From this an expression for complex phase speed of individual waves is calculated. It is deduced that each wave in a group does not grow at the same rate. It is shown that the critical layer is no longer symmetrical compared with the ideal monochromatic waves. This asymmetry causes the critical layer height to be lower over …

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Growth Of Groups Of Wind Generated Waves, Frederique Drullion, Shahrdad Sajjadi Jul 2016

Growth Of Groups Of Wind Generated Waves, Frederique Drullion, Shahrdad Sajjadi

Publications

In this paper we demonstrate numerical computations of turbulent wind blowing over group of waves that are growing in time. The numerical model adopted for the turbulence model is based on differential second-moment model that was adopted for growing idealized waves by Drullion & Sajjadi (2014). The results obtained here demonstrate the formation of cat's-eye which appear asymmetrically over the waves within a group.

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Guidelines For Assessment And Instruction In Statistics Education (Gaise) College Report 2016, Robert Carver, Michelle Everson, John Gabrosek, Nicholas Horton, Robin Lock, Megan Mocko, Allan Rossman, Ginger Holmes Roswell, Paul Velleman, Jeffrey Witmer, Beverly Wood Jul 2016

Guidelines For Assessment And Instruction In Statistics Education (Gaise) College Report 2016, Robert Carver, Michelle Everson, John Gabrosek, Nicholas Horton, Robin Lock, Megan Mocko, Allan Rossman, Ginger Holmes Roswell, Paul Velleman, Jeffrey Witmer, Beverly Wood

Publications

In 2005 the American Statistical Association (ASA) endorsed the Guidelines for Assessment and Instruction in Statistics Education (GAISE) College Report. This report has had a profound impact on the teaching of introductory statistics in two- and four-year institutions, and the six recommendations put forward in the report have stood the test of time. Much has happened within the statistics education community and beyond in the intervening 10 years, making it critical to re-evaluate and update this important report. For readers who are unfamiliar with the original GAISE College Report or who are new to the statistics education community, the full …

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Aviation And Cybersecurity: Opportunities For Applied Research, Jon Haass, Radhakrishna Sampigethaya, Vincent Capezzuto Jul 2016

Aviation And Cybersecurity: Opportunities For Applied Research, Jon Haass, Radhakrishna Sampigethaya, Vincent Capezzuto

Publications

Aviation connects the global community and is moving more people and payloads faster than ever. The next decade will experience an increase in manned and unmanned aircraft and systems with new features and unprecedented applications. Cybertechnologies—including software, computer networks, and information technology—are critical and fundamental to these advances in meeting the needs of the aviation ecosystem of aircraft, pilots, personnel, passengers, stakeholders, and society. This article discusses current and evolving threats as well as opportunities for applied research to improve the global cybersecurity stance in the aviation and connected transportation industry of tomorrow.

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Plasma Transport Driven By The Rayleigh-Taylor Instability, X. Ma, P. A. Delamere, A. Otto Jun 2016

Plasma Transport Driven By The Rayleigh-Taylor Instability, X. Ma, P. A. Delamere, A. Otto

Publications

Two important differences between the giant magnetospheres (i.e., Jupiter's and Saturn's magnetospheres) and the terrestrial magnetosphere are the internal plasma sources and the fast planetary rotation. Thus, there must be a radially outward flow to transport the plasma to avoid infinite accumulation of plasma. This radial outflow also carries the magnetic flux away from the inner magnetosphere due to the frozen‐in condition. As such, there also must be a radial inward flow to refill the magnetic flux in the inner magnetosphere. Due to the similarity between Rayleigh‐Taylor (RT) instability and the centrifugal instability, we use a three‐dimensional RT instability to …

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Gw151226: Observation Of Gravitational Waves From A 22-Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Jun 2016

Gw151226: Observation Of Gravitational Waves From A 22-Solar-Mass Binary Black Hole Coalescence, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5 σ. The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 to 450 …

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Search For Transient Gravitational Waves In Coincidence With Short-Duration Radio Transients During 2007-2013, B. P. Abbott, K. Gill, B. Hughey, D. Stiles, M. Szczepańczyk, M. Zanolin, Et Al. Jun 2016

Search For Transient Gravitational Waves In Coincidence With Short-Duration Radio Transients During 2007-2013, B. P. Abbott, K. Gill, B. Hughey, D. Stiles, M. Szczepańczyk, M. Zanolin, Et Al.

Publications

We present an archival search for transient gravitational-wave bursts in coincidence with 27 single pulse triggers from Green Bank Telescope pulsar surveys, using the LIGO, Virgo and GEO interferometer network. We also discuss a check for gravitational-wave signals in coincidence with Parkes Fast Radio Bursts using similar methods. Data analyzed in these searches were collected between 2007 and 2013. Possible sources of emission of both short-duration radio signals and transient gravitational-wave emission include starquakes on neutron stars, binary coalescence of neutron stars, and cosmic string cusps. While no evidence for gravitational-wave emission in coincidence with these radio transients was found, …

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Observing Gravitational-Wave Transient Gw150914 With Minimal Assumptions, B. P. Abbott, K. Gill, B. Hughey, M. Szczepańczyk, M. Zanolin, Et Al. Jun 2016

Observing Gravitational-Wave Transient Gw150914 With Minimal Assumptions, B. P. Abbott, K. Gill, B. Hughey, M. Szczepańczyk, M. Zanolin, Et Al.

Publications

The gravitational-wave signal GW150914 was first identified on September 14, 2015, by searches for short-duration gravitational-wave transients. These searches identify time-correlated transients in multiple detectors with minimal assumptions about the signal morphology, allowing them to be sensitive to gravitational waves emitted by a wide range of sources including binary black hole mergers. Over the observational period from September 12 to October 20, 2015, these transient searches were sensitive to binary black hole mergers similar to GW150914 to an average distance of ∼600  Mpc. In this paper, we describe the analyses that first detected GW150914 as well as the parameter estimation …

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Characterization Of Transient Noise In Advanced Ligo Relevant To Gravitational Wave Signal Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al. Jun 2016

Characterization Of Transient Noise In Advanced Ligo Relevant To Gravitational Wave Signal Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

On September 14, 2015, a gravitational wave signal from a coalescing black hole binary system was observed by the Advanced LIGO detectors. This paper describes the transient noise backgrounds used to determine the significance of the event (designated GW150914) and presents the results of investigations into potential correlated or uncorrelated sources of transient noise in the detectors around the time of the event. The detectors were operating nominally at the time of GW150914. We have ruled out environmental influences and non-Gaussian instrument noise at either LIGO detector as the cause of the observed gravitational wave signal.

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Morphisms And Order Ideals Of Toric Posets, Matthew Macauley Jun 2016

Morphisms And Order Ideals Of Toric Posets, Matthew Macauley

Publications

Toric posets are in some sense a natural “cyclic” version of finite posets in that they capture the fundamental features of a partial order but without the notion of minimal or maximal elements. They can be thought of combinatorially as equivalence classes of acyclic orientations under the equivalence relation generated by converting sources into sinks, or geometrically as chambers of toric graphic hyperplane arrangements. In this paper, we define toric intervals and toric order-preserving maps, which lead to toric analogues of poset morphisms and order ideals. We develop this theory, discuss some fundamental differences between the toric and ordinary cases, …

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Cost Estimation Model For Pan Based Carbon Fiber Manufacturing Process, Amaninder Singh Gill, Darian Visotsky, Laine Mears, Joshua D. Summers Jun 2016

Cost Estimation Model For Pan Based Carbon Fiber Manufacturing Process, Amaninder Singh Gill, Darian Visotsky, Laine Mears, Joshua D. Summers

Publications

A polyacrilonitrile (PAN) based carbon fiber manufacturing cost estimation model driven by weight is presented in this study. One of the biggest limiting factors in the large scale use of carbon fiber (CF) in manufacturing is its high cost. The costs involved in manufacturing the carbon fiber have been formalized into a cost model in order to facilitate the understanding of these factors. This can play a key role in manufacturing CF in a cost effective method. This cost model accounts for the fixed and variable costs involved in all stages of manufacturing, in addition to accounting for price elasticity.

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Improved Tests Of Lorentz Invariance In The Matter Sector Using Atomic Clocks, H. Pihan-Le Bars, C. Guerlin, Q. G. Bailey, S. Bize, P. Wolf Jun 2016

Improved Tests Of Lorentz Invariance In The Matter Sector Using Atomic Clocks, H. Pihan-Le Bars, C. Guerlin, Q. G. Bailey, S. Bize, P. Wolf

Publications

For the purpose of searching for Lorentz-invariance violation in the minimal Standard-Model Extension, we perfom a reanalysis of data obtained from the 133Cs fountain clock operating at SYRTE. The previous study led to new limits on eight components of the ˜cµν tensor, which quantifies the anisotropy of the proton’s kinetic energy. We recently derived an advanced model for the frequency shift of hyperfine Zeeman transition due to Lorentz violation and became able to constrain the ninth component, the isotropic coefficient c˜TT, which is the least well-constrained coefficient of ˜cµν. This model is based on a second-order boost Lorentz transformation from …

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Gravity Sector Of The Sme, Q. G. Bailey Jun 2016

Gravity Sector Of The Sme, Q. G. Bailey

Publications

In this talk, the gravity sector of the effective field theory description of local Lorentz violation is discussed, including minimal and nonminimal curvature couplings. Also, recent experimental and observational analyses including solar-system ephemeris and short-range gravity tests are reviewed.

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Constraints On Sme Coefficients From Lunar Laser Ranging, Very Long Baseline Interferometry, And Asteroid Orbital Dynamics, C. Le Poncin-Lafitte, A. Bourgoin, A. Hees, S. Bouquillon, S. Lambert, Q. G. Bailey, Et Al. Jun 2016

Constraints On Sme Coefficients From Lunar Laser Ranging, Very Long Baseline Interferometry, And Asteroid Orbital Dynamics, C. Le Poncin-Lafitte, A. Bourgoin, A. Hees, S. Bouquillon, S. Lambert, Q. G. Bailey, Et Al.

Publications

Lorentz symmetry violations can be parametrized by an effective field theory framework that contains both General Relativity and the Standard Model of particle physics, called the Standard-Model Extension or SME. We consider in this work only the pure gravitational sector of the minimal SME. We present new constraints on the SME coefficients obtained from lunar laser ranging, very long baseline interferometry, and planetary motions.

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A Field Study To Promote Undergraduate Student Learning Through Inquiry-Based Research, Thomas G. Henkel, James Paul, Debra T. Bourdeau Jun 2016

A Field Study To Promote Undergraduate Student Learning Through Inquiry-Based Research, Thomas G. Henkel, James Paul, Debra T. Bourdeau

Publications

The purpose of this study was to explore methods to promote effective undergraduate student learning through inquiry-based research in the classroom and to determine what the benefits of doing so might be. The study begins by outlining how undergraduate inquiry-based research increases the undergraduate student learning model and then lists steps to accomplish this process. The study outlines two options offered as a workable process to promote faculty and student inquiry-based in-class research. The first option is for undergraduate students to engage in inquiry-based research with the assistance of one-on- one mentoring by the instructor. The second option allows for …

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The White Dwarf Luminosity Function, Enrique Garcia-Berro, Terry D. Oswalt Jun 2016

The White Dwarf Luminosity Function, Enrique Garcia-Berro, Terry D. Oswalt

Publications

White dwarfs are the final remnants of low- and intermediate-mass stars. Their evolution is essentially a cooling process that lasts for ∼ 10 Gyr. Their observed properties provide information about the history of the Galaxy, its dark matter content and a host of other interesting astrophysical problems. Examples of these include an independent determination of the past history of the local star formation rate, identification of the objects responsible for the reported microlensing events, constraints on the rate of change of the gravitational constant, and upper limits to the mass of weakly interacting massive particles. To carry on these tasks …

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Prospects For Sme Tests With Experiments At Syrte And Lkb, C. Guerlin, H. Pihan-Le Bars, Q. G. Bailey, P. Wolf Jun 2016

Prospects For Sme Tests With Experiments At Syrte And Lkb, C. Guerlin, H. Pihan-Le Bars, Q. G. Bailey, P. Wolf

Publications

Preliminary work has been done in order to assess the perspectives of metrology and fundamental physics atomic experiments at SYRTE and LKB in the search for physics beyond the Standard Model and General Relativity. The first studies we identified are currently ongoing with the Microscope mission and with a Cs fountain clock. The latter brings significant improvement on the proton-sector coefficient cTT down to the 10−17 GeV level.

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Gaiseing Into The New Guidelines, Robert Carver, Megan Mocko, Jeffrey Witmer, Beverly Wood May 2016

Gaiseing Into The New Guidelines, Robert Carver, Megan Mocko, Jeffrey Witmer, Beverly Wood

Publications

The first GAISE College Report came out in 2005. Over the past ten years our discipline has changed in many ways, including but not limited to what type of data is easily available, the technology that we use, as well as how we teach students. In this presentation we will briefly start with how the new GAISE 2016 guidelines and goals have changed, including the two new emphases of statistical thinking: giving students experience with multivariable thinking and with the investigative process. So how do you start to implement these new ideas? In this presentation, we will demonstrate an activity …

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The Dawn–Dusk Asymmetry Of Ion Density In The Dayside Magnetosheath And Its Annual Variability Measured By Themis, Andrew P. Dimmock, Tuija I. Pulkkinen, Adnane Osmane, Katariina Nykyri May 2016

The Dawn–Dusk Asymmetry Of Ion Density In The Dayside Magnetosheath And Its Annual Variability Measured By Themis, Andrew P. Dimmock, Tuija I. Pulkkinen, Adnane Osmane, Katariina Nykyri

Publications

The local and global plasma properties in the magnetosheath play a fundamental role in regulating solar wind–magnetosphere coupling processes. However, the magnetosheath is a complex region to characterise as it has been shown theoretically, observationally and through simulations that plasma properties are inhomogeneous, non-isotropic and asymmetric about the Sun-Earth line. To complicate matters, dawn–dusk asymmetries are sensitive to various changes in the upstream conditions on an array of timescales. The present paper focuses exclusively on dawn–dusk asymmetries, in particularly that of ion density. We present a statistical study using THEMIS data of the dawn–dusk asymmetry of ion density in the …

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A Percentile-Based Power Method In Sas: Simulating Multivariate Non-Normal Continuous Distributions, Jennifer Koran, Todd C. Headrick May 2016

A Percentile-Based Power Method In Sas: Simulating Multivariate Non-Normal Continuous Distributions, Jennifer Koran, Todd C. Headrick

Publications

The conventional power method transformation is a moment-matching technique that simulates non-normal distributions with controlled measures of skew and kurtosis. The percentile-based power method is an alternative that uses the percentiles of a distribution in lieu of moments. This article presents a SAS/IML macro that implements the percentile-based power method.

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Statistical Modeling Of Defect Propensity In Manual Assembly As Applied To Automotive Electrical Connectors, Matthew Krugh, Kavit Antani, Laine Mears, Jörg Schulte May 2016

Statistical Modeling Of Defect Propensity In Manual Assembly As Applied To Automotive Electrical Connectors, Matthew Krugh, Kavit Antani, Laine Mears, Jörg Schulte

Publications

Assembly represents a significant fraction of overall manufacturing time and total manufacturing cost in the automotive industry. With increasing product complexity and variety, humans remain a cost effective solution to meet the needs of flexible manufacturing systems. This element necessitates a better understanding of the human role in manufacturing complexity. Presented herein is a framework for enumerating assembly variables correlated with the potential for quality defects, presented in the design, process, and human factors domain. A case study is offered that illustrates a method to identify variables and their effect on assembly quality for a manual assembly process.

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Assessing The Advantages Of Using Square Wave Signals For Particle Trapping In Carbon-Electrode Dielectrophoresis, Guillermo Contreras-Dávila, Jose I. Gomez-Quiñones, Victor H. Pérez-González, Rodrigo Martinez-Duarte May 2016

Assessing The Advantages Of Using Square Wave Signals For Particle Trapping In Carbon-Electrode Dielectrophoresis, Guillermo Contreras-Dávila, Jose I. Gomez-Quiñones, Victor H. Pérez-González, Rodrigo Martinez-Duarte

Publications

Here we present an improvement on the trapping efficiency of 3D carbon electrode Dielectrophoresis (carbonDEP) by using alternative signal geometries to the more traditional sine used to stimulate the electrodes. In particular, a square waveform is used. Theoretical analysis was based on the Root Mean Square (RMS) values and the Fourier Series Expansion of these signals. Computational modeling was performed to calculate the DEP force generated by the two signal waveforms and allowed for direct comparison. The trapping efficiency between square and sine signals was then determined experimentally. Given the same experiment characteristics, the use of square signals allows for …

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Local Standards For Sample Size At Chi, Kelly Caine May 2016

Local Standards For Sample Size At Chi, Kelly Caine

Publications

We describe the primary ways researchers can determine the size of a sample of research participants, present the benefits and drawbacks of each of those methods, and focus on improving one method that could be useful to the CHI community: local standards. To determine local standards for sample size within the CHI community, we conducted an analysis of all manuscripts published at CHI2014. We find that sample size for manuscripts published at CHI ranges from 1 -- 916,000 and the most common sample size is 12. We also find that sample size differs based on factors such as study setting …

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Shrinkage Analysis Of Carbon Micro Structures Derived From Su-8 Photoresist, Rucha Natu, Monsur Islam, Rodrigo Martinez-Duarte May 2016

Shrinkage Analysis Of Carbon Micro Structures Derived From Su-8 Photoresist, Rucha Natu, Monsur Islam, Rodrigo Martinez-Duarte

Publications

We present preliminary results for the analysis of shrinkage of 3D carbon posts obtained by the pyrolysis of SU-8 precursor structures, in a technique known as Carbon MEMS. Though the shrinkage in the carbon structures is highly reproducible, there is a strong dependence of this shrinkage on the initial dimensions of the SU-8 pillars. Our hypothesis is that the shrinkage depends upon the area available for degassing during carbonization. In this work, this idea is used to analyze shrinkage in cylindrical pillars. The results obtained are studied based on the ratio of lateral and top surface area available for degassing …

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