Chaotic Mixing in Microchannels Via Low Frequency Switching Transverse Electroosmotic flow Generated on Integrated Microelectrodes
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DWF-Healing Lessons
UC Berkeley UC Berkeley Electronic Theses and Dissertations Title Healing Lessons: Urban High School Teachers Learning to Teach Black Youth with Post- Traumatic Stress Disorder Permalink https://escholarship.org/uc/item/9d39k1kv Author Ferreira, Dawn Williams Publication Date 2012 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California Healing Lessons: Urban High School Teachers Learning to Teach Black Youth with Post-Traumatic Stress Disorder By Dawn Ligaya Custodio Williams Ferreira A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Education in the Graduate Division of the University of California, Berkeley Committee in charge: Professor Jabari Mahiri, Chair Professor Na’ilah Suad Na’sir Professor Malo André Hutson Spring 2012 Healing Lessons: Urban High School Teachers Learning to Teach Black Youth with Post-Traumatic Stress Disorder © Dawn Ligaya Custodio Williams Ferreira, 2012 Abstract Healing Lessons: Urban High School Teachers Learning to Teach Black Youth with Post-Traumatic Stress Disorder By Dawn Ligaya Custodio Williams Ferreira Doctor of Philosophy in Education University of California, Berkeley Professor Jabari Mahiri, Chair Significant research reveals that youth who reside in neighborhoods of high crime and violence can often be exposed to external stressors that result in Post-Traumatic Stress Disorder (PTSD). These youths are disproportionately Black, and this condition often goes untreated. Consequently, their challenges with PTSD can surface and have tremendous impacts on teaching and learning at the schools they attend. These impacts include severe problems with academic achievement and discipline. The site of this research is a public, urban continuation high school in Northern California where many students exhibit symptoms of PTSD. -
Mixing, Chaotic Advection, and Turbulence
Annual Reviews www.annualreviews.org/aronline Annu. Rev. Fluid Mech. 1990.22:207-53 Copyright © 1990 hV Annual Reviews Inc. All r~hts reserved MIXING, CHAOTIC ADVECTION, AND TURBULENCE J. M. Ottino Department of Chemical Engineering, University of Massachusetts, Amherst, Massachusetts 01003 1. INTRODUCTION 1.1 Setting The establishment of a paradigm for mixing of fluids can substantially affect the developmentof various branches of physical sciences and tech- nology. Mixing is intimately connected with turbulence, Earth and natural sciences, and various branches of engineering. However, in spite of its universality, there have been surprisingly few attempts to construct a general frameworkfor analysis. An examination of any library index reveals that there are almost no works textbooks or monographs focusing on the fluid mechanics of mixing from a global perspective. In fact, there have been few articles published in these pages devoted exclusively to mixing since the first issue in 1969 [one possible exception is Hill’s "Homogeneous Turbulent Mixing With Chemical Reaction" (1976), which is largely based on statistical theory]. However,mixing has been an important component in various other articles; a few of them are "Mixing-Controlled Supersonic Combustion" (Ferri 1973), "Turbulence and Mixing in Stably Stratified Waters" (Sherman et al. 1978), "Eddies, Waves, Circulation, and Mixing: Statistical Geofluid Mechanics" (Holloway 1986), and "Ocean Tur- bulence" (Gargett 1989). It is apparent that mixing appears in both indus- try and nature and the problems span an enormous range of time and length scales; the Reynolds numberin problems where mixing is important varies by 40 orders of magnitude(see Figure 1). -
Chapter 3. Society and the Individual at the Dawn of the Twenty-First
CHAPTER 3 Society and the Individual at the Dawn of the Twenty-First Century Toni C. Antonucci1,*, Lisa Berkman2,*, Axel Börsch-Supan3,*, Laura L. Carstensen4,*, Linda P. Fried5,*, Frank F. Furstenberg6,*, Dana Goldman7,*, James S. Jackson1,*, Martin Kohli8,*, S. Jay Olshansky9,*, John Rother10,*, John W. Rowe11,*, and Julie Zissimopoulos7,* *MacArthur Foundation Research Network on an Aging Society, 1Department of Psychology, University of Michigan, Ann Arbor, MI, USA, 2Harvard Center for Population and Development Studies, Harvard University, Cambridge, MA, USA, 3Munich Center for the Economics of Aging, University of Munich, Germany, 4Department of Psychology, Stanford University, Stanford, CA, USA, 5Mailman School of Public Health, Columbia University, New York, NY, USA, 6Department of Sociology Department, University of Pennsylvania, Philadelphia, PA, USA, 7Schaeffer Center for Health Policy and Economics, University of Southern California, Los Angeles, CA, USA, 8Bremen International Graduate School of Social Sciences, European University Institute, San Domenico di Fiesole, Italy, 9School of Public Health, University of Illinois at Chicago, Chicago, IL, USA, 10National Coalition on Health Care, Washington DC, WA, USA, 11Department of Health Policy & Management, Mailman School of Public Health, Columbia University, New York, NY, USA K.W. Schaie & S.L. Willis (Eds) DOI: http://dx.doi.org/10.1016/B978-0-12-411469-2.00003-0 Handbook of the Psychology of Aging, Eighth edition. 41 © 20162015 Elsevier Inc. All rights reserved. 42 3. SOCIETY AND THE INDIVIDUAL at THE DAWN OF THE TWENTY-FIRST CENTURY OUTLINE Introduction 42 Work and Retirement 50 Policies and Practices 52 A Comment on Lifespan Psychology 43 Family Life 53 Health and Health Care 44 Policies and Practices 56 Policies and Practices 46 Summary and Conclusions 58 Education 48 Policies and Practices 49 References 58 INTRODUCTION future is perilous, and we do not aim to do so. -
Chaos and Chaotic Fluid Mixing
Snapshots of modern mathematics № 4/2014 from Oberwolfach Chaos and chaotic fluid mixing Tom Solomon Very simple mathematical equations can give rise to surprisingly complicated, chaotic dynamics, with be- havior that is sensitive to small deviations in the ini- tial conditions. We illustrate this with a single re- currence equation that can be easily simulated, and with mixing in simple fluid flows. 1 Introduction to chaos People used to believe that simple mathematical equations had simple solutions and complicated equations had complicated solutions. However, Henri Poincaré (1854–1912) and Edward Lorenz [4] showed that some remarkably simple math- ematical systems can display surprisingly complicated behavior. An example is the well-known logistic map equation: xn+1 = Axn(1 − xn), (1) where xn is a quantity (between 0 and 1) at some time n, xn+1 is the same quantity one time-step later and A is a given real number between 0 and 4. One of the most common uses of the logistic map is to model variations in the size of a population. For example, xn can denote the population of adult mayflies in a pond at some point in time, measured as a fraction of the maximum possible number the adult mayfly population can reach in this pond. Similarly, xn+1 denotes the population of the next generation (again, as a fraction of the maximum) and the constant A encodes the influence of various factors on the 1 size of the population (ability of pond to provide food, fraction of adults that typically reproduce, fraction of hatched mayflies not reaching adulthood, overall mortality rate, etc.) As seen in Figure 1, the behavior of the logistic system changes dramatically with changes in the parameter A. -
Chaotic Mixing Induced Transitions in Reaction–Diffusion Systems Zolta´N Neufeld and Peter H
CHAOS VOLUME 12, NUMBER 2 JUNE 2002 Chaotic mixing induced transitions in reaction–diffusion systems Zolta´n Neufeld and Peter H. Haynes Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, United Kingdom Tama´sTe´l Eo¨tvo¨s University, Department of Theoretical Physics, H-1518 Budapest, Hungary ͑Received 6 November 2001; accepted 7 March 2002; published 20 May 2002͒ We study the evolution of a localized perturbation in a chemical system with multiple homogeneous steady states, in the presence of stirring by a fluid flow. Two distinct regimes are found as the rate of stirring is varied relative to the rate of the chemical reaction. When the stirring is fast localized perturbations decay towards a spatially homogeneous state. When the stirring is slow ͑or fast reaction͒ localized perturbations propagate by advection in form of a filament with a roughly constant width and exponentially increasing length. The width of the filament depends on the stirring rate and reaction rate but is independent of the initial perturbation. We investigate this problem numerically in both closed and open flow systems and explain the results using a one-dimensional ‘‘mean-strain’’ model for the transverse profile of the filament that captures the interplay between the propagation of the reaction–diffusion front and the stretching due to chaotic advection. © 2002 American Institute of Physics. ͓DOI: 10.1063/1.1476949͔ The problem of chemical or biological activity in fluid Equation ͑1͒ can be nondimensionalized by the transfor- flows has recently become an area of active research.1–8 mations Apart from theoretical interest this problem has a num- x tU v k ber of industrial9 and environmental10,11 applications. -
2020 Korean Books for Young Readers
2020 Korean Books for Young Readers Korean Board on Books for Young People (IBBY Korea) About Contents KBBY and this Catalog KBBY(Korean Board on Books for Young People) was founded in 1995 7 Korean Nominees for the Hans Christian Andersen Awards 4 as the Korea national section of the International Board on Books for Young People (IBBY). Korean Nominations for the IBBY Honour List 2020 12 To fulfill IBBY’s mission, KBBY works as a network of professionals from both home and abroad, collecting and sharing information on Korean Nominations for BIB 2019 14 children’s and juvenile literature. KBBY also works in close partnership with the other national sections of IBBY to contribute to promoting Korean Nominations for Silent Books 2019 22 cross-cultural exchange in children’s literature. Recent Picture Books Recommended by KBBY Since 2017 25 KBBY organizes international book exhibitions in collaboration with library networks, in efforts to share with the Korean audience the in- formation on global books generated through the awards and activ- Recent Chapter Books and Novels Recommended by KBBY Since 2017 37 ities of IBBY. Moreover, KBBY is committed to providing information on outstanding Korean children’s and juvenile literature with readers Recent Non-fiction Recommended by KBBY Since 2017 50 across the world. This catalog presents the Korean nominees of the Hans Christian An- dersen Awards, who have made a lasting impact on children’s litera- ture not only at home but also to the world at large. Also included is a collection of the Korean children’s books recommended by the book selection committee of KBBY: Korean nominations for the IBBY Honour List, BIB, Silent Books; recent picutre books, chapter books & novels, and non-finction books. -
Coercive Change of Religion in South Korea»
Coercive Change of Religion in South Korea» A report on the practice of kidnapping, confinement and forced de-conversion in South Korea. March 2020 Human Rights Without Frontiers 4 Coercive Change of Religion in South Korea By Willy Fautré Human Rights Without Frontiers 2020 No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from Human Rights Without Frontiers International or Bitter Winter. Requests for permission to make copies of any part of this publication should be sent to the address below. Human Rights Without Frontiers International Avenue d’Auderghem 61/16, 1040 Brussels, Belgium Tel. (+32) 2 345 61 45 Email: [email protected] – Website: https://hrwf.eu Table of Contents Foreword ................................................................................................................................... 1 PART I Introduction .................................................................................................................... 5 What is the Shincheonji Church? ................................................................................... 7 Family kidnappings and coercive de-conversion ........................................................... 9 ‘Anti-heretical counseling centers’ ............................................................................. 13 International conference in Seoul 2019 ...................................................................... -
Chaotic Mixing of Viscous Fluids
Why study fluid mixing - Context Mechanisms of mixing What is the speed of dye mixing in closed flows ? Mixing in open flows Chaotic mixing of viscous fluids Topological entanglement and transport barriers Emmanuelle Gouillart Joint Unit CNRS/Saint-Gobain, Aubervilliers Olivier Dauchot, CEA Saclay Jean-Luc Thiffeault, University of Wisconsin Why study fluid mixing - Context Mechanisms of mixing What is the speed of dye mixing in closed flows ? Mixing in open flows Outline 1 Why study fluid mixing - Context 2 Mechanisms of mixing 3 What is the speed of dye mixing in closed flows ? 4 Mixing in open flows Why study fluid mixing - Context Mechanisms of mixing What is the speed of dye mixing in closed flows ? Mixing in open flows Plan 1 Why study fluid mixing - Context 2 Mechanisms of mixing 3 What is the speed of dye mixing in closed flows ? 4 Mixing in open flows Why study fluid mixing - Context Mechanisms of mixing What is the speed of dye mixing in closed flows ? Mixing in open flows Fluid mixing is ubiquituous in the industry... Mixing step in many processes Low Reynolds number : no turbulence Closed (batch) or open flows Why study fluid mixing - Context Mechanisms of mixing What is the speed of dye mixing in closed flows ? Mixing in open flows ... or in the environment Why study fluid mixing - Context Mechanisms of mixing What is the speed of dye mixing in closed flows ? Mixing in open flows What we would like to know about fluid mixing Why study fluid mixing - Context Mechanisms of mixing What is the speed of dye mixing in closed flows ? Mixing in open flows What -
“The Social Cut of Black and Yellow Female Hip Hop” Erick Raven
“The Social Cut of Black and Yellow Female Hip Hop” Erick Raven University of Texas at Arlington May 2020 Abstract Korean female hip hop artists are expanding the definition of femininity in South Korea through hip hop. In doing so, they are following a tradition first established by Black female musical performers in a new context. Korean artists are conceiving and expressing, through rap and dance, alternative versions of a “Korean woman,” thus challenging and attempting to add to the dominant conceptions of “woman.” This Thesis seeks to point out the ways female Korean hip hop artists are engaging dominant discourse regarding skin tone, body type, and expression of female sexuality, and creating spaces for the development of new discourses about gender in South Korean society. Contents Introduction – Into the Cut ................................................ 1 Chapter I – Yoon Mi-rae and Negotiating the West and East of Colorism ............................................................. 12 Chapter II – The Performing Black and Yellow Female Body ................................................................................ 31 Chapter III – Performing Sexuality ................................. 47 Chapter IV – Dis-Orientation .......................................... 59 Conclusion .................................................................... 67 Works Cited .................................................................... 70 Introduction – Into the Cut Identities are performed discourse; they are formed when those who identify as a particular personality perform and establish a discourse in a particular social context. As George Lipsitz states, “improvisation is a site of encounter” (61). In South Korea, female Korean hip hop is the site of a social cut in dominant culture and has become a space of improvisation where new, counter-hegemonic identities are constructed and performed. In this Thesis, I argue that Korean female hip hop artists are enacting a social rupture by performing improvised identities. -
Downloading the App and Where They Were Located, Which Can Be Used in the Future to Help
April 2017 Dear IMSA Students, Faculty, Staff, and Friends: This is IMSA's 30th year of leading in educational innovation and the 29th year of the Student Inquiry and Research Program (SIR)! Welcome to another year of profound investigation and discovery! In these pages, you will find exciting abstracts on a variety of fantastic studies done by IMSA's great minds. Our students are carrying out studies on topics including Alzheimer's Disease, the Soviet Great Terror, genetic “switches” for cancer, epidemiology, genetics, satellite tracking systems, environmental pollution, entrepreneurship, public opinion, engineering energy, climate change, high energy physics, supersymmetry, market dynamics, water filtration, love, language, machine learning, diabetic pain, black holes, neural networks, and many many more! The subjects reflect our students’ diverse interests and the broad research community that supports them. These studies have all happened during the past year in a variety of laboratories, real or virtual, on and off campus. Students were asked to not only learn a great deal about complex topics, but to contribute to them in meaningful ways. The presentations you hear today reflect the various stages of their work on a myriad of projects. This work could not happen without the tireless work of the many Research Mentors in the Student Inquiry and Research program. The mentors, whether they come from IMSA or external institutions, give their time and resources to the cause of aiding our students' growth. Many also involve their research teams in the mentoring and molding of our students. Their efforts directly working with students, as well as supporting the scheduling, negotiation, and execution of the SIR program, are invaluable. -
Parametric Investigation on Mixing in a Micromixer with Two-Layer Crossing Channels
Hossain and Kim SpringerPlus (2016) 5:794 DOI 10.1186/s40064-016-2477-x RESEARCH Open Access Parametric investigation on mixing in a micromixer with two‑layer crossing channels Shakhawat Hossain and Kwang‑Yong Kim* *Correspondence: [email protected] Abstract Department of Mechanical This work presents a parametric investigation on flow and mixing in a chaotic micro‑ Engineering, Inha University, Incheon 402‑751, Republic mixer consisting of two-layer crossing channels proposed by Xia et al. (Lab Chip 5: of Korea 748–755, 2005). The flow and mixing performance were numerically analyzed using commercially available software ANSYS CFX-15.0, which solves the Navier–Stokes and mass conservation equations with a diffusion–convection model in a Reynolds number range from 0.2 to 40. A mixing index based on the variance of the mass fraction of the mixture was employed to evaluate the mixing performance of the micromixer. The flow structure in the channel was also investigated to identify the relationship with mixing performance. The mixing performance and pressure-drop were evaluated with two dimensionless geometric parameters, i.e., ratios of the sub-channel width to the main channel width and the channels depth to the main channel width. The results revealed that the mixing index at the exit of the micromixer increases with increase in the channel depth-to-width ratio, but decreases with increase in the sub-channel width to main channel width ratio. And, it was found that the mixing index could be increased up to 0.90 with variations of the geometric parameters at Re 0.2, and the pressure drop was very sensitive to the geometric parameters. -
Laminar Mixing of High-Viscous Fluids by a Novel Chaotic Mixer
Laminar mixing of high-viscous fluids by a novel chaotic mixer S. M. Hosseinalipour*, P. R. Mashaei, M. E. J. Muslomani School of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran Article info: Abstract Received: 08/07/2016 In this study, an experimental examination of laminar mixing in a novel chaotic mixer was carried out by blob deformation method. The mixer was a circular Accepted: 17/11/2018 vessel with two rotational blades which move along two different circular paths Online: 17/11/2018 with a stepwise motion protocol. The flow visualization was performed by Keywords: coloration of the free surface of the flow with a material tracer. The effects of Chaotic mixer, significant parameters such as rotational speed of blades, blades length, and rotational speed amplitude on mixing efficiency and time were analyzed by Laminar flow, measuring of the area covered by the tracer. The results revealed that increasing Average rotational rotational speed intensifies stretching and folding phenomena; consequently, speed, better mixing is obtained. Also, a better condition in flow kinematic was Mixing index. provided to blend, as stepwise motion protocol with wider amplitude applied. A reduction in mixing time could be observed while the blades with longer length were used. In addition, it was also found that the promotion of mixing by rotational speed is more effective than that of two other parameters. The quantitative data and qualitative observations proved the potential of the proposed chaotic mixer in the wide range of industrial processes including chemical reaction and food processing in which laminar mixing is required.