Reflections on Applied Computational Aerodynamics (ACA) My Journey on a Long and Winding Road in the Quest for Fully Effective ACA—A Bridge Too Far!
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Antony Jameson Professor (Research), Department of Aeronautics and Astronautics Stanford University Stanford, California
Antony Jameson Professor (Research), Department of Aeronautics and Astronautics Stanford University Stanford, California For exceptional contributions to algorithmic innovation and the development of computational fluid dynamic codes that have made important contributions to aircraft design. The author of 444 scientific papers, Antony Jameson has made major contributions to many fields of aerospace science and technology, especially to the areas of computational fluid dynamics (CFD), control theory, and aerodynamics. In the words of the International Journal of CFD (November 2005): “Antony Jameson has had a huge impact on the field of Computational Fluid Dynamics for over four decades, opening up new avenues of research and developing tools to solve problems once thought beyond reach. From the formulation of a problem, to the development of the numerical technology to solve it, to the implementation of that technology in efficient tools and the fluid dynamical interpretation of results, Jameson has impacted most aspects of CFD.” Jameson is also credited with major breaKthroughs in the area of aerodynamic shape optimization, showing how CFD and control theory can be combined to allow designers to calculate optimum wing shapes which minimize drag and maximize performance. Jameson incorporated his numerical algorithms in two series of CFD codes: “FLO” (for flow analysis) and “SYN,” (for aerodynamic design) and both have played critical roles in developing some of the world’s most well-Known jetliners, including Airbus’ 320 and 330, as well as Boeing’s 737-500, 737-700, 747-400, and the 777. His work has advanced the state of CFD, with some noting that “many of the advances were propelled by the understanding, the algorithm technology, and the codes that were created by Jameson.” Aircraft manufacturers have universally used his codes for their CFD needs. -
Criticalreading #Wickedproblem
#CRITICALREADING #WICKEDPROBLEM We have a “wicked problem” . and that is a fantastic, engaging, exciting place to start. Carolyn V. Williams1 I. INTRODUCTION I became interested in the idea of critical reading—“learning to evaluate, draw inferences, and arrive at conclusions based on evidence” in the text2—when I assumed that my students would show up to law school with this skill . and then, through little fault of their own, they did not. I have not been the only legal scholar noticing this fact. During the 1980s and 90s a few legal scholars conducted research and wrote about law students’ reading skills.3 During the 2000s, a few more scholars wrote about how professors can help develop critical reading skills in law students.4 But it has not been until the past few years or so that legal scholars have begun to shine a light on just how deep the problem of law students’ critical reading skills 1 Professor Williams is an Associate Professor of Legal Writing & Assistant Clinical Professor of Law at the University of Arizona, James E. Rogers College of Law. Thank you to Dean Marc Miller for supporting this Article with a summer research grant. Many thanks to the Legal Writing Institute for hosting the 2018 We Write Retreat and the 2018 Writers’ Workshop and to the participants at each for their comments and support of this project. A heartfelt thank you to Mary Beth Beazley, Kenneth Dean Chestek, and Melissa Henke for graciously providing comments on prior drafts of this Article. Thank you to my oldest Generation Z child for demonstrating independence and the desire to fix broken systems so that I know my solution is possible. -
Evolving the Oblique Wing
NASA AERONAUTICS BOOK SERIES A I 3 A 1 A 0 2 H D IS R T A O W RY T A Bruce I. Larrimer MANUSCRIP . Bruce I. Larrimer Library of Congress Cataloging-in-Publication Data Larrimer, Bruce I. Thinking obliquely : Robert T. Jones, the Oblique Wing, NASA's AD-1 Demonstrator, and its legacy / Bruce I. Larrimer. pages cm Includes bibliographical references. 1. Oblique wing airplanes--Research--United States--History--20th century. 2. Research aircraft--United States--History--20th century. 3. United States. National Aeronautics and Space Administration-- History--20th century. 4. Jones, Robert T. (Robert Thomas), 1910- 1999. I. Title. TL673.O23L37 2013 629.134'32--dc23 2013004084 Copyright © 2013 by the National Aeronautics and Space Administration. The opinions expressed in this volume are those of the authors and do not necessarily reflect the official positions of the United States Government or of the National Aeronautics and Space Administration. This publication is available as a free download at http://www.nasa.gov/ebooks. Introduction v Chapter 1: American Genius: R.T. Jones’s Path to the Oblique Wing .......... ....1 Chapter 2: Evolving the Oblique Wing ............................................................ 41 Chapter 3: Design and Fabrication of the AD-1 Research Aircraft ................75 Chapter 4: Flight Testing and Evaluation of the AD-1 ................................... 101 Chapter 5: Beyond the AD-1: The F-8 Oblique Wing Research Aircraft ....... 143 Chapter 6: Subsequent Oblique-Wing Plans and Proposals ....................... 183 Appendices Appendix 1: Physical Characteristics of the Ames-Dryden AD-1 OWRA 215 Appendix 2: Detailed Description of the Ames-Dryden AD-1 OWRA 217 Appendix 3: Flight Log Summary for the Ames-Dryden AD-1 OWRA 221 Acknowledgments 230 Selected Bibliography 231 About the Author 247 Index 249 iii This time-lapse photograph shows three of the various sweep positions that the AD-1's unique oblique wing could assume. -
Supersonic Biplane Design Via Adjoint Method A
SUPERSONIC BIPLANE DESIGN VIA ADJOINT METHOD A DISSERTATION SUBMITTED TO THE DEPARTMENT OF AERONAUTICS AND ASTRONAUTICS AND THE COMMITTEE ON GRADUATE STUDIES OF STANFORD UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Rui Hu May 2009 c Copyright by Rui Hu 2009 All Rights Reserved ii I certify that I have read this dissertation and that, in my opinion, it is fully adequate in scope and quality as a dissertation for the degree of Doctor of Philosophy. (Antony Jameson) Principal Adviser I certify that I have read this dissertation and that, in my opinion, it is fully adequate in scope and quality as a dissertation for the degree of Doctor of Philosophy. (Robert W. MacCormack) I certify that I have read this dissertation and that, in my opinion, it is fully adequate in scope and quality as a dissertation for the degree of Doctor of Philosophy. (Gianluca Iaccarino) Approved for the University Committee on Graduate Studies. iii Abstract In developing the next generation supersonic transport airplane, two major challenges must be resolved. The fuel efficiency must be significantly improved, and the sonic boom propagating to the ground must be dramatically reduced. Both of these objec- tives can be achieved by reducing the shockwaves formed in supersonic flight. The Busemann biplane is famous for using favorable shockwave interaction to achieve nearly shock-free supersonic flight at its design Mach number. Its performance at off-design Mach numbers, however, can be very poor. This dissertation studies the performance of supersonic biplane airfoils at design and off-design conditions. -
Generation Times of E. Coli Prolong with Increasing Tannin Concentration While the Lag Phase Extends Exponentially
plants Article Generation Times of E. coli Prolong with Increasing Tannin Concentration while the Lag Phase Extends Exponentially Sara Štumpf 1 , Gregor Hostnik 1, Mateja Primožiˇc 1, Maja Leitgeb 1,2 and Urban Bren 1,3,* 1 Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor 2000, Slovenia; [email protected] (S.Š.); [email protected] (G.H.); [email protected] (M.P.); [email protected] (M.L.) 2 Faculty of Medicine, University of Maribor, Maribor 2000, Slovenia 3 Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Koper 6000, Slovenia * Correspondence: [email protected]; Tel.: +386-2-2294-421 Received: 18 November 2020; Accepted: 29 November 2020; Published: 1 December 2020 Abstract: The current study examines the effect of tannins and tannin extracts on the lag phase duration, growth rate, and generation time of Escherichia coli.Effects of castalagin, vescalagin, gallic acid, Colistizer, tannic acid as well as chestnut, mimosa, and quebracho extracts were determined on E. coli’s growth phases using the broth microdilution method and obtained by turbidimetric measurements. E. coli responds to the stress caused by the investigated antimicrobial agents with reduced growth rates, longer generation times, and extended lag phases. Prolongation of the lag phase was relatively small at low tannin concentrations, while it became more pronounced at concentrations above half the MIC. Moreover, for the first time, it was observed that lag time extensions follow a strict exponential relationship with increasing tannin concentrations. This feature is very likely a direct consequence of the tannin complexation of certain essential ions from the growth medium, making them unavailable to E. -
The Following Paper Posted Here Is Not the Official IEEE Published Version
The following paper posted here is not the official IEEE published version. The final published version of this paper can be found in the Proceedings of the IEEE International Conference on Communication, Volume 3:pp.1490-1494 Copyright © 2004 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Investigation and modeling of traffic issues in immersive audio environments Jeremy McMahon, Michael Rumsewicz Paul Boustead, Farzad Safaei TRC Mathematical Modelling Telecommunications and Information Technology Research University of Adelaide Institute South Australia 5005, AUSTRALIA University of Wollongong jmcmahon, [email protected] New South Wales 2522, AUSTRALIA [email protected], [email protected] Abstract—A growing area of technical importance is that of packets being queued at routers. distributed virtual environments for work and play. For the This is an area that has not undergone significant research audio component of such environments to be useful, great in the literature. Most of the available literature regarding emphasis must be placed on the delivery of high quality audio synchronization in multimedia relates to synchronizing audio scenes in which participants may change their relative positions. with video playout (e.g. [5], [6], [7]) and / or requires a global In this paper we describe and analyze an algorithm focused on maintaining relative synchronization between multiple users of synchronization clock such as GPS (e.g. -
Chapter 04 Lecture
Chapter 04 Lecture 1 A GLIMPSE OF HISTORY German physician Robert Koch (1843–1910) Studied disease-causing bacteria; Nobel Prize in 1905 Developed methods of cultivating bacteria Worked on methods of solid media to allow single bacteria to grow and form colonies Tried potatoes, but nutrients limiting for many bacteria • Solidifying liquid nutrient media with gelatin helped • Limitations: melting temperature, digestible • In 1882, Fannie Hess, wife of associate, suggested agar, then used to harden jelly INTRODUCTION Prokaryotes found growing in severe conditions Ocean depths, volcanic vents, polar regions all harbor thriving prokaryotic species Many scientists believe that if life exists on other planets, it may resemble these microbes Individual species have limited set of conditions Also require appropriate nutrients Important to grow microbes in culture Medical significance Nutritional, industrial uses 4.1. PRINCIPLES OF BACTERIAL GROWTH Prokaryotic cells divide by binary fission Cell gets longer and One cell divides into two, two DNA replicates. into four, 48, 816, etc… Exponential growth: population DNA is moved into each future daughter doubles each division cell and cross wall forms. Generation time is time it takes to double Varies among species Cell divides into two cells. Environmental conditions Exponential growth has important consequences Cells separate. 10 cells of food-borne pathogen in potato salad at picnic can become 40,000 cells in 4 hours Daughter cells 4.1. PRINCIPLES OF BACTERIAL GROWTH Growth can be calculated n Nt = N0 x 2 Nt = number of cells in population at time t N0 = original number of cells in population n = number of divisions Example: pathogen in potato salad at picnic in sun Assume 10 cells with 20 minute generation time N0 = 10 cells in original population n = 12 (3 divisions per hour for 4 hours) n 12 Nt = N0 x 2 = 10 x 2 Nt = 10 x 4,096 Nt = 40,960 cells of pathogen in 4 hours! 4.1. -
Pannexin 1 Transgenic Mice: Human Diseases and Sleep-Wake Function Revision
International Journal of Molecular Sciences Article Pannexin 1 Transgenic Mice: Human Diseases and Sleep-Wake Function Revision Nariman Battulin 1,* , Vladimir M. Kovalzon 2,3 , Alexey Korablev 1, Irina Serova 1, Oxana O. Kiryukhina 3,4, Marta G. Pechkova 4, Kirill A. Bogotskoy 4, Olga S. Tarasova 4 and Yuri Panchin 3,5 1 Laboratory of Developmental Genetics, Institute of Cytology and Genetics SB RAS, 630090 Novosibirsk, Russia; [email protected] (A.K.); [email protected] (I.S.) 2 Laboratory of Mammal Behavior and Behavioral Ecology, Severtsov Institute Ecology and Evolution, Russian Academy of Sciences, 119071 Moscow, Russia; [email protected] 3 Laboratory for the Study of Information Processes at the Cellular and Molecular Levels, Institute for Information Transmission Problems, Russian Academy of Sciences, 119333 Moscow, Russia; [email protected] (O.O.K.); [email protected] (Y.P.) 4 Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia; [email protected] (M.G.P.); [email protected] (K.A.B.); [email protected] (O.S.T.) 5 Department of Mathematical Methods in Biology, Belozersky Institute, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia * Correspondence: [email protected] Abstract: In humans and other vertebrates pannexin protein family was discovered by homology to invertebrate gap junction proteins. Several biological functions were attributed to three vertebrate pannexins members. Six clinically significant independent variants of the PANX1 gene lead to Citation: Battulin, N.; Kovalzon, human infertility and oocyte development defects, and the Arg217His variant was associated with V.M.; Korablev, A.; Serova, I.; pronounced symptoms of primary ovarian failure, severe intellectual disability, sensorineural hearing Kiryukhina, O.O.; Pechkova, M.G.; loss, and kyphosis. -
A Theory for the Age and Generation Time Distribution of a Microbial Population
Journal of Mathematical Biology 1, 17--36 (1974) by Springer-Verlag 1974 A Theory for the Age and Generation Time Distribution of a Microbial Population J. L. Lebowitz* and S. I. Rubinow, New York Received October 9, 1973 Summary A theory is presented for the time evolution of the joint age and generation time distribution of a microbial population. By means of the solution to the fundamental equation of the theory, the effect of correlations between the generation times of mother and daughter cells may be determined on the transient and steady state growth stages of the population. The relationships among various generation time distributions measured under different experimental circumstances is clarified. 1. Introduction A striking property of microbial populations, even when grown under constant environmental conditions, is the great variability of the generation times of individual members of the population, illustrated in Fig. 1. The cause of this variability remains an important unsolved biological problem. The variability is generally ascribed to intrinsic variable factors associated with cell growth and maturation, culminating in division [1]. Prescott [2] has suggested that the variability stems from variability in the initial state of a newborn cell, where initial state means cell weight, number of mitochondria, microsomes, etc. Variability in the initial state of the chromosome is likewise a fundamental feature of the Cooper-Helmstetter model for chromo- some replication in E. coli [3]. In both of these views, the generation time is determined at birth. * Also Physics Department, Belfer Graduate School of Sciences, Yeshiva University, New York, NY 10019, U.S.A. Journ. -
Causemap: Fast Inference of Causality from Complex Time Series
CauseMap: fast inference of causality from complex time series M. Cyrus Maher1 and Ryan D. Hernandez2,3,4 1 Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA 2 Department of Bioengineering and Therapeutic Sciences, USA 3 Institute for Human Genetics, USA 4 Institute for Quantitative Biosciences (QB3), University of California, San Francisco, CA, USA ABSTRACT Background. Establishing health-related causal relationships is a central pursuit in biomedical research. Yet, the interdependent non-linearity of biological systems renders causal dynamics laborious and at times impractical to disentangle. This pursuit is further impeded by the dearth of time series that are suYciently long to observe and understand recurrent patterns of flux. However, as data generation costs plummet and technologies like wearable devices democratize data collection, we anticipate a coming surge in the availability of biomedically-relevant time series data. Given the life-saving potential of these burgeoning resources, it is critical to invest in the development of open source software tools that are capable of drawing meaningful insight from vast amounts of time series data. Results. Here we present CauseMap, the first open source implementation of convergent cross mapping (CCM), a method for establishing causality from long time series data (&25 observations). Compared to existing time series methods, CCM has the advantage of being model-free and robust to unmeasured confounding that could otherwise induce spurious associations. CCM builds on Takens’ Theorem, a well-established result from dynamical systems theory that requires only mild assumptions. This theorem allows us to reconstruct high dimensional system dy- namics using a time series of only a single variable. -
File:Thinking Obliquely.Pdf
NASA AERONAUTICS BOOK SERIES A I 3 A 1 A 0 2 H D IS R T A O W RY T A Bruce I. Larrimer MANUSCRIP . Bruce I. Larrimer Library of Congress Cataloging-in-Publication Data Larrimer, Bruce I. Thinking obliquely : Robert T. Jones, the Oblique Wing, NASA's AD-1 Demonstrator, and its legacy / Bruce I. Larrimer. pages cm Includes bibliographical references. 1. Oblique wing airplanes--Research--United States--History--20th century. 2. Research aircraft--United States--History--20th century. 3. United States. National Aeronautics and Space Administration-- History--20th century. 4. Jones, Robert T. (Robert Thomas), 1910- 1999. I. Title. TL673.O23L37 2013 629.134'32--dc23 2013004084 Copyright © 2013 by the National Aeronautics and Space Administration. The opinions expressed in this volume are those of the authors and do not necessarily reflect the official positions of the United States Government or of the National Aeronautics and Space Administration. This publication is available as a free download at http://www.nasa.gov/ebooks. Introduction v Chapter 1: American Genius: R.T. Jones’s Path to the Oblique Wing .......... ....1 Chapter 2: Evolving the Oblique Wing ............................................................ 41 Chapter 3: Design and Fabrication of the AD-1 Research Aircraft ................75 Chapter 4: Flight Testing and Evaluation of the AD-1 ................................... 101 Chapter 5: Beyond the AD-1: The F-8 Oblique Wing Research Aircraft ....... 143 Chapter 6: Subsequent Oblique-Wing Plans and Proposals ....................... 183 Appendices Appendix 1: Physical Characteristics of the Ames-Dryden AD-1 OWRA 215 Appendix 2: Detailed Description of the Ames-Dryden AD-1 OWRA 217 Appendix 3: Flight Log Summary for the Ames-Dryden AD-1 OWRA 221 Acknowledgments 230 Selected Bibliography 231 About the Author 247 Index 249 iii This time-lapse photograph shows three of the various sweep positions that the AD-1's unique oblique wing could assume. -
Robert Jones
NATIONAL ACADEMY OF SCIENCES ROBERT THOMAS JONES 1910– 1999 A Biographical Memoir by WALTER G. VINCENTI Any opinions expressed in this memoir are those of the author and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoirs, VOLUME 86 PUBLISHED 2005 BY THE NATIONAL ACADEMIES PRESS WASHINGTON, D.C. ROBERT THOMAS JONES May 28, 1910–August 11, 1999 BY WALTER G. VINCENTI HE PLANFORM OF THE wing of every high-speed transport Tone sees flying overhead embodies R. T. Jones’s idea of sweepback for transonic and supersonic flight. This idea, of which Jones was one of two independent discoverers, was described by the late William Sears, a distinguished aerody- namicist who was a member of the National Academy of Sciences, as “certainly one of the most important discover- ies in the history of aerodynamics.” It and other achieve- ments qualify him as among the premier theoretical aero- dynamicists of the twentieth century. And this by a remarkable man whose only college degree was an honorary doctorate. Robert Thomas Jones––“R.T.” to those of us fortunate enough to be his friend––was born on May 28, 1910, in the farming-country town of Macon, Missouri, and died on Au- gust 11, 1999, at age 89, at his home in Los Altos Hills, California. His immigrant grandfather, Robert N. Jones, af- ter being in the gold rush to California, settled near Ma- con, where he farmed in the summer and mined coal in the winter. His father, Edward S. Jones, educated himself in the law and practiced law in Macon; while running for pub- lic office, he traveled the dirt roads of Macon county in a buggy behind a single horse.