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2019

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Impulse Measurements Of Electric Solid Propellant In An Electrothermal Ablation-Fed Pulsed Plasma Thruster, Matthew S. Glascock, Joshua L. Rovey, Kurt A. Polzin Jan 2019

Impulse Measurements Of Electric Solid Propellant In An Electrothermal Ablation-Fed Pulsed Plasma Thruster, Matthew S. Glascock, Joshua L. Rovey, Kurt A. Polzin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Electric solid propellants are advanced solid chemical rocket propellants that can be controlled (ignited, throttled and extinguished) through the application and removal of an electric current. These propellants are also being considered for use in the ablative pulsed plasma thruster. In this paper, the performance of an electric solid propellant operating in an electrothermal ablation-fed pulsed plasma thruster was investigated using an inverted pendulum micro-Newton thrust stand. The impulse bit and specific impulse of the device using the electric solid propellant were measured for short-duration test runs of 100 pulses and longer-duration runs to end-of-life, at energy levels of 5, …

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Electric Solid Propellant Ablation In An Arc Discharge, Matthew S. Glascock, Joshua L. Rovey, Kurt A. Polzin Jan 2019

Electric Solid Propellant Ablation In An Arc Discharge, Matthew S. Glascock, Joshua L. Rovey, Kurt A. Polzin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Electric solid propellants are advanced solid chemical rocket propellants that can be controlled (ignited, throttled, and extinguished) through the application and removal of an electric current. Electric solid propellants are also being considered for pulsed arc ablation electric thrusters, such as the pulsed plasma thruster. The focus of this work is the electrical and ablation characteristics of electric solid propellant within an arc discharge. Arc discharges of 5–20 J per pulse were created within a cylindrical cavity, and results for the electric solid propellant are compared with polytetrafluoroethylene (PTFE), which is a traditional propellant in ablative pulsed plasma thrusters. The …

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Atomistic Simulations Of Nanoindentation Response Of Irradiation Defects In Iron, M. Mustafa Azeem, Qingyu Wang, Muhammad Zubair Jan 2019

Atomistic Simulations Of Nanoindentation Response Of Irradiation Defects In Iron, M. Mustafa Azeem, Qingyu Wang, Muhammad Zubair

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Radiation response of a material is a consequence of defects' evolution in any radiation damage event. The radiation-induced defects can significantly alter the mechanical properties of a material. Radiation damage initiates from incident neutron by bombardment on solid material causing production and evolution of Frenkel defects. Since voids are formed due to aggregation of a large number of vacancies that cause dimensional changes and hence irradiation-induced swelling. In order to characterize the effect of irradiation defects, we have performed molecular dynamics (MD) simulations to investigate nanoindentation response of point defects and voids in Fe and their effects on mechanical parameters. …

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Introduction To The Special Issue: Increasing Space For Families On The Margins, Lynn H. Turner Jan 2019

Introduction To The Special Issue: Increasing Space For Families On The Margins, Lynn H. Turner

College of Communication Faculty Research and Publications

No abstract provided.

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Infant Baptism, William B. Godbey Jan 2019

Infant Baptism, William B. Godbey

William B. Godbey

No abstract provided.

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A Brief Overview Of The Christian Endeavor Society, Brian Clifford Hull Jan 2019

A Brief Overview Of The Christian Endeavor Society, Brian Clifford Hull

Books

No abstract provided.

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“But How Could We Sing A Song Of The Lord In A Foreign Land?” An Esl/Esp Class For Catholic Immigrants, Mary C. Tillotson Jan 2019

“But How Could We Sing A Song Of The Lord In A Foreign Land?” An Esl/Esp Class For Catholic Immigrants, Mary C. Tillotson

Master's Theses and Doctoral Dissertations

The U.S. Catholic population has a larger proportion of immigrants than the U.S. population at large. The majority of Catholic immigrants come from Latin America and are not native speakers of English. In this qualitative study, I interviewed nine Catholic immigrants from Latin America to better understand their experiences of navigating their Catholic faith in the United States and the role an English-as-a-second-language (ESL) class could play in helping them successfully adjust to United States Catholicism. Findings suggest that, beyond a general ESL class, an English-for-specific-purposes class, capitalizing on the universality of Catholicism and specialized for Catholic prayer, liturgy, sacraments, …

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Gis Analysis Of The Mid-Nineteenth Century Emigration Of The Old Lutherans From Prussia, Joel Seewald Jan 2019

Gis Analysis Of The Mid-Nineteenth Century Emigration Of The Old Lutherans From Prussia, Joel Seewald

Master's Theses and Doctoral Dissertations

The Old Lutherans constituted fewer than 20% of the Germans who emigrated from Prussia between 1835 and 1854. In this study, more than 483 cities and villages of origin of 6,911 Old Lutherans were mapped. These origins were in the central provinces of Brandenburg, Pomerania, Posen, Saxony, and Silesia. More emigrants came from Pomerania overall and during every time period except 1849-54. The areas with the most emigrants were north central Pomerania, northern Brandenburg, southeast Brandenburg, and western Silesia. Emigrant destinations were primarily America and Australia. American destinations included New York, Wisconsin, and Texas, but the state that many went …

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Life In The Noodles, Junnan Xia Jan 2019

Life In The Noodles, Junnan Xia

Theses

One day, a Chinese international student, Zhou Yu, is considering his going home to China, since he doesn’t have a good life in America. That day, when Yu is in the supermarket shopping, he sees his ex-girl friend, Chen Xue. Xue is friendly and asks Yu to come to her home and she wants to treat Yu a bowl of noodles, which is her special treat that she made for Yu before. Yu struggles but finally he is moved by Xue’s great passion. When they arrived at Xue’s place, they start to eat and talk. Xue is curious about Yu’s …

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The Successful Transition Of Black Men At Historically White Universities, Regina M. George Jan 2019

The Successful Transition Of Black Men At Historically White Universities, Regina M. George

Master's Theses and Doctoral Dissertations

There is something going on with Black men in America who go to college. As university enrollment has become more diverse with all ethnic and economic groups attending in greater numbers, as Black women are graduating at unprecedented rates, as postsecondary education becomes an increasingly significant employment requirement, the persistence to graduation rate of Black men as a group is among the lowest. Historically White institutions of higher education seek to ensure academic success and increase 4-6 year graduation rates for all students. Perhaps Black men can inform the process and lift everyone with their knowledge. This is a qualitative …

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An Experimental Approach That Assesses In-Situ Micro-Scale Damage Mechanisms And Fracture Toughness In Thermoplastic Laminates Under Out-Of-Plane Loading, H. Wafai, A. Yudhanto, G. Lubineau, R. Yaldiz, N. Verghese Jan 2019

An Experimental Approach That Assesses In-Situ Micro-Scale Damage Mechanisms And Fracture Toughness In Thermoplastic Laminates Under Out-Of-Plane Loading, H. Wafai, A. Yudhanto, G. Lubineau, R. Yaldiz, N. Verghese

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Studying the response of laminated composites under out-of-plane loading routinely involves mechanical tests, such as quasi-static indentation or impact. The phenomenology during these tests is so complex that it is difficult to identify different material properties related to each failure mechanism (damage mode). We aim at providing an experimental approach, which is practical and fast, for assessing the in-situ micro-scale damage mechanism and extracting the fracture toughness in thermoplastic laminates under out-of-plane loading. To this end, we developed a dedicated, micro-scale, three-point bending (micro-3PB) test fitted inside a scanning electron microscope (SEM). In a single experiment, we were able: (i) …

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Synthesis And Study Of The Micellization Behavior Of A Dual Temperature- And Ph-Responsive Paa-B-Pnipam Block Copolymer, Ehsan Zarshenas Moghadam Jan 2019

Synthesis And Study Of The Micellization Behavior Of A Dual Temperature- And Ph-Responsive Paa-B-Pnipam Block Copolymer, Ehsan Zarshenas Moghadam

Master's Theses and Doctoral Dissertations

Amphiphilic diblock copolymers are composed of hydrophilic and hydrophobic regions. When they are exposed to water, the hydrophobic blocks aggregate to form a hydrophobic core surrounded by hydrophilic regions outside to give a core-shell micelle. These micelles have many potential applications, such as a drug delivery system, surfactants, or nanoreactor. Many studies have been done to optimize the performance of these copolymers. In this thesis work, nine dual temperature- and pH-responsive poly(acrylic acid-block-N-isopropylacrylamide) (PAA-b-PNIPAM) diblock copolymers with different relative chain lengths of the hydrophobic and hydrophilic blocks were synthesized by reversible addition fragmentation chain transfer polymerization. The preliminary results showed …

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Thermodynamic And Transport Properties Of Hydroxylammonium Nitrate-Based Electric Solid Propellant Vapor, Matthew S. Glascock, Patrick D. Drew, Joshua L. Rovey Jan 2019

Thermodynamic And Transport Properties Of Hydroxylammonium Nitrate-Based Electric Solid Propellant Vapor, Matthew S. Glascock, Patrick D. Drew, Joshua L. Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Electric solid propellants are advanced solid chemical rocket propellants controlled by electric current. Electric solid propellants may also be used in an electric propulsion system, specifically, an ablative pulsed plasma thruster. Previous experiments with the electric solid propellant HIPEP suggest its ablation processes are similar to traditional propellant polytetrafluoroethylene (C2F4). Better understanding of the ablation and resulting propulsion performance of HIPEP requires a model of its vapor composition and transport properties. This paper reports on the development of such a model. The model was validated by comparing results for C2F4 with literature, which showed agreement with multiple models described. Transport …

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Experimental Investigation Of Mixtures Of 1-Ethyl-3-Methylimidazolium Ethyl Sulfate And Ethylammonium Nitrate With Electrospray Propulsion Applications, Mitchell J. Wainwright, Joshua L. Rovey, Shawn W. Miller, Benjamin D. Prince Jan 2019

Experimental Investigation Of Mixtures Of 1-Ethyl-3-Methylimidazolium Ethyl Sulfate And Ethylammonium Nitrate With Electrospray Propulsion Applications, Mitchell J. Wainwright, Joshua L. Rovey, Shawn W. Miller, Benjamin D. Prince

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Physical properties, performance metrics, and mass spectra of mixtures of two ionic liquids (1-ethyl-3-methylimidazolium ethyl-sulfate aka [Emim][EtSO4] and ethyl ammonium nitrate aka EAN) are investigated from the standpoint of electrospray propulsive characteristics. Spectra suggest that as the [Emim][EtSO4] mixture fraction increases, the intensity of [Emim][EtSO4] related species in the plume also increases, while the presence of EAN decreases. Spectra also show presence of both EAN proton transfer species and species related to chemical reaction of [EtSO4] and water. Despite the volatility of EAN, it emits stably into vacuum at low flow rates when mixed with 25% [Emim][EtSO4]. Spectra also show …

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Influence Of A Backward-Facing Step On Swept-Wing Boundary-Layer Transition, Jenna L. Eppink, Richard W. Wlezien, Rudolph A. King, Meelan Choudhari Jan 2019

Influence Of A Backward-Facing Step On Swept-Wing Boundary-Layer Transition, Jenna L. Eppink, Richard W. Wlezien, Rudolph A. King, Meelan Choudhari

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Experimental measurements were performed on a swept flat-plate model with an airfoil leading edge and imposed chordwise pressure gradient to determine the effects of a backward-facing step on transition in a low-speed stationary crossflow-dominated boundary layer. Detailed hot-wire measurements were performed for three step heights ranging from 36 to 49% of the boundary-layer thickness at the step and corresponding to subcritical, nearly critical, and critical cases. In general, the step had a small, localized effect on the growth of the stationary crossflow vortex, whereas the unsteady disturbance amplitudes increased with increasing step height. Intermittent spikes in instantaneous velocity began to …

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Hydroxylammonium Nitrate Species In A Monopropellant Electrospray Plume, Mitchell J. Wainwright, Joshua L. Rovey, Shawn W. Miller, Benjamin D. Prince, Steven P. Berg Jan 2019

Hydroxylammonium Nitrate Species In A Monopropellant Electrospray Plume, Mitchell J. Wainwright, Joshua L. Rovey, Shawn W. Miller, Benjamin D. Prince, Steven P. Berg

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A mixture of 1-ethyl-3-methylimidazolium ethyl sulfate ([Emim][EtSO4]) and hydroxylammonium nitrate (HAN) is an energetic monopropellant potentially suitable in a multi-mode chemical-electric microtube-electrospray micro propulsion system. In this work, electrospray plume mass spectra are compared between the monopropellant mixture and neat [Emim][EtSO4]. This comparison clearly indicates new and additional species present in the plume due to the addition of HAN. Mass spectra from 20-600 amu/q were obtained over a variety of angles and flow rates from 2 pL/sec to 3 nL/sec in both cation and anion extraction modes. Mass spectrum dependence on flow rate and angular orientation agree qualitatively well with …

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[Chapter 1 From] Viral Modernism: The Influenza Pandemic And Interwar Literature, Elizabeth Outka Jan 2019

[Chapter 1 From] Viral Modernism: The Influenza Pandemic And Interwar Literature, Elizabeth Outka

Bookshelf

The influenza pandemic of 1918–1919 took the lives of between 50 and 100 million people worldwide, and the United States suffered more casualties than in all the wars of the twentieth and twenty-first centuries combined. Yet despite these catastrophic death tolls, the pandemic faded from historical and cultural memory in the United States and throughout Europe, overshadowed by World War One and the turmoil of the interwar period. In Viral Modernism, Elizabeth Outka reveals the literary and cultural impact of one of the deadliest plagues in history, bringing to light how it shaped canonical works of fiction and poetry. …

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[Introduction To] Constructing The Adolescent Reader In Contemporary Young Adult Fiction, Elisabeth Rose Gruner Jan 2019

[Introduction To] Constructing The Adolescent Reader In Contemporary Young Adult Fiction, Elisabeth Rose Gruner

Bookshelf

This book examines the way young adult readers are constructed in a variety of contemporary young adult fictions, arguing that contemporary young adult novels depict readers as agents. Reading, these novels suggest, is neither an unalloyed good nor a dangerous ploy, but rather an essential, occasionally fraught, by turns escapist and instrumental, deeply pleasurable, and highly contentious activity that has value far beyond the classroom skills or the specific content it conveys. After an introductory chapter that examines the state of reading and young adult fiction today, the book examines novels that depict reading in school, gendered and racialized reading, …

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[Introduction To] Animate Literacies: Literature, Affect, And The Politics Of Humanism, Nathan Snaza Jan 2019

[Introduction To] Animate Literacies: Literature, Affect, And The Politics Of Humanism, Nathan Snaza

Bookshelf

In Animate Literacies Nathan Snaza proposes a new theory of literature and literacy in which he outlines how literacy is both constitutive of the social and used as a means to define the human. Weaving new materialism with feminist, queer, and decolonial thought, Snaza theorizes literacy as a contact zone in which humans, nonhuman animals, and nonvital objects such as chairs and paper all become active participants. In readings of classic literature by Kate Chopin, Frederick Douglass, James Joyce, Toni Morrison, Mary Shelley, and others, Snaza emphasizes the key roles that affect and sensory experiences play in literacy. Snaza upends …

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[Introduction To] Soda Goes Pop: Pepsi-Cola Advertising And Popular Music, Joanna K. Love Jan 2019

[Introduction To] Soda Goes Pop: Pepsi-Cola Advertising And Popular Music, Joanna K. Love

Bookshelf

From its 1939 “Nickel, Nickel” jingle to pathbreaking collaborations with Michael Jackson and Madonna to its pair of X Factor commercials in 2011 and 2012, Pepsi-Cola has played a leading role in drawing the American pop music industry into a synergetic relationship with advertising. This idea has been copied successfully by countless other brands over the years, and such commercial collaboration is commonplace today—but how did we get here? How and why have pop music aesthetics been co-opted to benefit corporate branding? What effect have Pepsi’s music marketing practices in particular had on other brands, the advertising industry, and popular …

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Enhanced Quantum Dots Spontaneous Emission With Metamaterial Perfect Absorbers, Wei Wang, Xiaodong Yang, Ting S. Luk, Jie Gao Jan 2019

Enhanced Quantum Dots Spontaneous Emission With Metamaterial Perfect Absorbers, Wei Wang, Xiaodong Yang, Ting S. Luk, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metamaterial perfect absorbers (PAs) made of a hexagonal array of holes on Ag-SiO 2 -Ag thin films have been realized and utilized to enhance the spontaneous emission rate and photoluminescence intensity of CdSe/ZnS quantum dots (QDs) spin-coated on the absorber top surface. Perfect absorption of incoming light occurs at the wavelength where the impedance is matched to that of the free space. When QDs strongly excite both the electric and magnetic resonances at this perfect absorption wavelength, a significant Purcell effect on the spontaneous emission process and enhanced radiative outcoupling of photoluminescence intensity are expected. For perfect absorbers with near-unity …

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Silence And The Second Wall, Zachary New, Ming Hsu Chen Jan 2019

Silence And The Second Wall, Zachary New, Ming Hsu Chen

Faculty Scholarship

No abstract provided.

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Propagating, Evanescent, And Complex Wavenumber Guided Waves In High-Performance Composites, Victor Giurgiutiu, Mohammad Faisal Haider Jan 2019

Propagating, Evanescent, And Complex Wavenumber Guided Waves In High-Performance Composites, Victor Giurgiutiu, Mohammad Faisal Haider

Faculty Publications

The study of propagating, evanescent and complex wavenumbers of guided waves (GWs) in high-performance composites using a stable and robust semi-analytical finite element (SAFE) method is presented. To facilitate understanding of the wavenumber trajectories, an incremental material change study is performed moving gradually from isotropic aluminum alloy to carbon fiber reinforced polymer (CFRP) composites. The SAFE results for an isotropic aluminum alloy plate are compared with the exact analytical solutions, which shows that N = 20 SAFE elements across the thickness provides <0.5% error in the highest evanescent wavenumber for the given frequency-wavenumber range. The material change study reveals that reducing the transverse and shear moduli moves the wavenumber solution towards one similar to composite material. The comparison of the propagating, evanescent and complex wavenumber trajectories between composites and aluminum alloy show that antisymmetric imaginary Lamb wave modes always exist in composites although they may not exist in isotropic aluminum alloy at some frequencies. The wavenumber trajectories for a unidirectional CFRP plate show that the range of real wavenumber is much smaller than in the isotropic aluminum alloy. For laminated CFRP composite plates (e.g., unidirectional, off-axis, transverse, cross-ply and quasi-isotropic laminates), the quasi Lamb wave and shear horizontal (SH) wave trajectories are also identified and discussed. The imaginary SH wave trajectories in laminated composites are distorted due to the presence of ±45 plies. The convergence study of the SAFE method in various CFRP laminates indicates that sufficient accuracy can always be achieved by increasing the number of SAFE elements. Future work will address the stress-continuity between composite layers.

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Symmetric Constitutionalism: An Essay On Masterpiece Cakeshop And The Post-Kennedy Supreme Court, Zachary S. Price Jan 2019

Symmetric Constitutionalism: An Essay On Masterpiece Cakeshop And The Post-Kennedy Supreme Court, Zachary S. Price

Faculty Scholarship

No abstract provided.

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Grace V. Whitaker: Advancing Refugee Rights Beyond The Credible Fear Interview, Richard A. Boswell, Elisa Vari Jan 2019

Grace V. Whitaker: Advancing Refugee Rights Beyond The Credible Fear Interview, Richard A. Boswell, Elisa Vari

Faculty Scholarship

No abstract provided.

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Scattered: The Assimilation Of Sushi, The Internment Of Japanese Americans, And The Killing Of Vincent Chin, A Personal Essay, Frank Wu Jan 2019

Scattered: The Assimilation Of Sushi, The Internment Of Japanese Americans, And The Killing Of Vincent Chin, A Personal Essay, Frank Wu

Faculty Scholarship

In a personal Essay, Frank H. Wu discusses the acceptance of sushi in America as a means of analyzing the acceptance of Japanese Americans, before, during, and after World War II. The murder of Vincent Chin in Detroit in 1982 is used as a defining moment for Asian Americans, explaining the shared experiences of people perceived as "perpetual foreigners."

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Between Law And Diplomacy: The Conundrum Of Common Law Immunity, Chimene Keitner Jan 2019

Between Law And Diplomacy: The Conundrum Of Common Law Immunity, Chimene Keitner

Faculty Scholarship

Drawing the line between disputes that can be adjudicated in domestic (U.S.) courts and those that cannot has perplexed judges and jurists since the Founding Era. Although Congress provided a statutory framework for the jurisdictional immunities of foreign states in 1976, important ambiguities remain. Notably, in 2010, the U.S. Supreme Court held in Samantar v. Yousuf that the Foreign Sovereign Immunities Act (FSIA) does not govern suits against foreign officials unless the foreign state is the "real party in interest." This decision clarified, but did not fully resolve, conceptual and doctrinal questions surrounding the immunities of foreign officials whose conduct …

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A Common Law Perspective On The Supreme Court And Its Functions, Richard L. Marcus Jan 2019

A Common Law Perspective On The Supreme Court And Its Functions, Richard L. Marcus

Faculty Scholarship

The text presents different attributes of the Supreme Court in common law and civil law systems. The author claims that the question of design and function of a supreme court, while important, is no more significant than the issue of its institutional status and evolution, i.e. something one could refer to as “legal culture”. Neither the “common law camp”, nor the “civil law camp” turns out to be monolithic in this regard. The distinctive history of the US Supreme Court is presented through the perspective of its statutory and procedural supremacy, as well as its power of constitutional adjudication. The …

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The Second Decade Of Numeracy: Entering The Seas Of Literacy, H. L. Vacher Jan 2019

The Second Decade Of Numeracy: Entering The Seas Of Literacy, H. L. Vacher

Numeracy

This multipurpose editorial explores and tries to count the many types of literacy that are referred to by name in Wikipedia and Numeracy. Wikipedia’s Category:Literacy page identifies 44 kinds of literacy that are the subject of articles, ranging from numeracy and graphicacy to braille literacy and diaspora literacy. In addition, searching Google finds more than 30 adjective-literacy or noun-literacy collocations, including quantitative literacy, adult literacy, and document literacy, that do not have Wikipedia pages of their own but are mentioned on other Wikipedia pages. The sum puts this modest literacy count in line with the more than 70 bodies …

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Brave Spaces: Augmenting Interdisciplinary Stem Education By Using Quantitative Data Explorations To Engage Conversations On Equity And Social Justice, John R. Jungck, Jon Manon Jan 2019

Brave Spaces: Augmenting Interdisciplinary Stem Education By Using Quantitative Data Explorations To Engage Conversations On Equity And Social Justice, John R. Jungck, Jon Manon

Numeracy

In workshops and courses involving in-service teachers, participating teachers can engage in problem posing and exploration of difficult issues when they are asked to quantitatively model alternative scenarios, statistically analyze complex data, and visualize these data in multiple formats. Subsequent to these activities, discussions of sensitive issues, some even considered taboo in classrooms, can open up “brave spaces” in these teachers’ classrooms. Without coaching through elaborate facilitation strategies, the in-service teachers grappled openly with the nuances of such difficult issues and raised many alternatives involving quantitative reasoning as well as considering biological, cultural, economic, social, and political factors influencing social …

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