Media Culture 2020: Collaborative Teaching and Blended Learning Using Social Media and Cloud-Based Technologies

ERIC Educational Resources Information Center

Vickers, Richard; Field, James; Melakoski, Cai

2015-01-01

In 2013 five universities from across Europe undertook an innovative project "Media Culture 2020", combining skills and forces to develop new practices that would face the challenge of the convergence of digital media, taking full advantage of social media and cloud-based technologies. The aim of the Media Culture 2020 project was to…

Adolescent Sex and Mass Media: A Developmental Approach.

ERIC Educational Resources Information Center

Chapin, John R.

2000-01-01

Media critics point to adolescents' exposure to "sexy" television and popular music. Developmental transitions lead to increased information seeking, and developmental tasks force adolescents to find information sources other than their parents, implying a link between sexy media and adolescent development. Media research informed by knowledge of…

7 CFR 3201.78 - Blast media.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 15 2013-01-01 2013-01-01 false Blast media. 3201.78 Section 3201.78 Agriculture... Items § 3201.78 Blast media. (a) Definition. Abrasive particles sprayed forcefully to clean, remove... qualifying biobased blast media. By that date, Federal agencies that have the responsibility for drafting or...

7 CFR 3201.78 - Blast media.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 15 2014-01-01 2014-01-01 false Blast media. 3201.78 Section 3201.78 Agriculture... Items § 3201.78 Blast media. (a) Definition. Abrasive particles sprayed forcefully to clean, remove... qualifying biobased blast media. By that date, Federal agencies that have the responsibility for drafting or...

Advanced Magnetic Materials Methods and Numerical Models for Fluidization in Microgravity and Hypogravity

NASA Technical Reports Server (NTRS)

Atwater, James; Wheeler, Richard, Jr.; Akse, James; Jovanovic, Goran; Reed, Brian

2013-01-01

To support long-duration manned missions in space such as a permanent lunar base, Mars transit, or Mars Surface Mission, improved methods for the treatment of solid wastes, particularly methods that recover valuable resources, are needed. The ability to operate under microgravity and hypogravity conditions is essential to meet this objective. The utilization of magnetic forces to manipulate granular magnetic media has provided the means to treat solid wastes under variable gravity conditions by filtration using a consolidated magnetic media bed followed by thermal processing of the solid wastes in a fluidized bed reactor. Non-uniform magnetic fields will produce a magnetic field gradient in a bed of magnetically susceptible media toward the distributor plate of a fluidized bed reactor. A correctly oriented magnetic field gradient will generate a downward direct force on magnetic media that can substitute for gravitational force in microgravity, or which may augment low levels of gravity, such as on the Moon or Mars. This approach is termed Gradient Magnetically Assisted Fluidization (G-MAFB), in which the magnitude of the force on the fluidized media depends upon the intensity of the magnetic field (H), the intensity of the field gradient (dH/dz), and the magnetic susceptibility of the media. Fluidized beds based on the G-MAFB process can operate in any gravitational environment by tuning the magnetic field appropriately. Magnetic materials and methods have been developed that enable G-MAFB operation under variable gravity conditions.

Impact Load Behavior between Different Charge and Lifter in a Laboratory-Scale Mill

PubMed Central

Yin, Zixin; Zhu, Zhencai; Yu, Zhangfa; Li, Tongqing

2017-01-01

The impact behavior between the charge and lifter has significant effect to address the mill processing, and is affected by various factors including mill speed, mill filling, lifter height and media shape. To investigate the multi-body impact load behavior, a series of experiments and Discrete Element Method (DEM) simulations were performed on a laboratory-scale mill, in order to improve the grinding efficiency and prolong the life of the lifter. DEM simulation hitherto has been extensively applied as a leading tool to describe diverse issues in granular processes. The research results shown as follows: The semi-empirical power draw of Bond model in this paper does not apply very satisfactorily for the ball mills, while the power draw determined by DEM simulation show a good approximation for the measured power draw. Besides, the impact force on the lifter was affected by mill speed, grinding media filling, lifter height and iron ore particle. The maximum percent of the impact force between 600 and 1400 N is at 70–80% of critical speed. The impact force can be only above 1400 N at the grinding media filling of 20%, and the maximum percent of impact force between 200 and 1400 N is obtained at the grinding media filling of 20%. The percent of impact force ranging from 0 to 200 N decreases with the increase of lifter height. However, this perfect will increase above 200 N. The impact force will decrease when the iron ore particles are added. Additionally, for the 80% of critical speed, the measured power draw has a maximum value. Increasing the grinding media filling increases the power draw and increasing the lifter height does not lead to any variation in power draw. PMID:28773243

Impact Load Behavior between Different Charge and Lifter in a Laboratory-Scale Mill.

PubMed

Yin, Zixin; Peng, Yuxing; Zhu, Zhencai; Yu, Zhangfa; Li, Tongqing

2017-07-31

The impact behavior between the charge and lifter has significant effect to address the mill processing, and is affected by various factors including mill speed, mill filling, lifter height and media shape. To investigate the multi-body impact load behavior, a series of experiments and Discrete Element Method (DEM) simulations were performed on a laboratory-scale mill, in order to improve the grinding efficiency and prolong the life of the lifter. DEM simulation hitherto has been extensively applied as a leading tool to describe diverse issues in granular processes. The research results shown as follows: The semi-empirical power draw of Bond model in this paper does not apply very satisfactorily for the ball mills, while the power draw determined by DEM simulation show a good approximation for the measured power draw. Besides, the impact force on the lifter was affected by mill speed, grinding media filling, lifter height and iron ore particle. The maximum percent of the impact force between 600 and 1400 N is at 70-80% of critical speed. The impact force can be only above 1400 N at the grinding media filling of 20%, and the maximum percent of impact force between 200 and 1400 N is obtained at the grinding media filling of 20%. The percent of impact force ranging from 0 to 200 N decreases with the increase of lifter height. However, this perfect will increase above 200 N. The impact force will decrease when the iron ore particles are added. Additionally, for the 80% of critical speed, the measured power draw has a maximum value. Increasing the grinding media filling increases the power draw and increasing the lifter height does not lead to any variation in power draw.

Social Experiments

ERIC Educational Resources Information Center

Slover-Linett, Cheryl; Stoner, Michael

2010-01-01

Earlier this year, CASE formed a social media task force to explore what educational institutions are trying to achieve with social media presence and learn about social media engagements at member institutions. CASE, in partnership with mStoner and Slover Linett Strategies, in June launched a benchmarking survey on social media in advancement by…

Online, Tuned In, Turned On: Multimedia Approaches to Fostering Critical Media Health Literacy for Adolescents

ERIC Educational Resources Information Center

Begoray, Deborah L.; Banister, Elizabeth M.; Wharf Higgins, Joan; Wilmot, Robin

2014-01-01

The commercial media is an influential sociocultural force and transmitter of health information especially for adolescents. Instruction in critical media health literacy, a combination of concepts from critical health literacy and critical media literacy, is a potentially effective means of raising adolescents' awareness about commercial media…

Characteristics of undulatory locomotion in granular media

NASA Astrophysics Data System (ADS)

Peng, Zhiwei; Pak, On Shun; Elfring, Gwynn J.

2016-03-01

Undulatory locomotion is ubiquitous in nature and observed in different media, from the swimming of flagellated microorganisms in biological fluids, to the slithering of snakes on land, or the locomotion of sandfish lizards in sand. Despite the similarity in the undulating pattern, the swimming characteristics depend on the rheological properties of different media. Analysis of locomotion in granular materials is relatively less developed compared with fluids partially due to a lack of validated force models but recently a resistive force theory in granular media has been proposed and shown useful in studying the locomotion of a sand-swimming lizard. Here we employ the proposed model to investigate the swimming characteristics of a slender filament, of both finite and infinite length, undulating in a granular medium and compare the results with swimming in viscous fluids. In particular, we characterize the effects of drifting and pitching in terms of propulsion speed and efficiency for a finite sinusoidal swimmer. We also find that, similar to Lighthill's results using resistive force theory in viscous fluids, the sawtooth swimmer is the optimal waveform for propulsion speed at a given power consumption in granular media. The results complement our understanding of undulatory locomotion and provide insights into the effective design of locomotive systems in granular media.

Drag force scaling for penetration into granular media.

PubMed

Katsuragi, Hiroaki; Durian, Douglas J

2013-05-01

Impact dynamics is measured for spherical and cylindrical projectiles of many different densities dropped onto a variety non-cohesive granular media. The results are analyzed in terms of the material-dependent scaling of the inertial and frictional drag contributions to the total stopping force. The inertial drag force scales similar to that in fluids, except that it depends on the internal friction coefficient. The frictional drag force scales as the square-root of the density of granular medium and projectile, and hence cannot be explained by the combination of granular hydrostatic pressure and Coulomb friction law. The combined results provide an explanation for the previously observed penetration depth scaling.

Force law in material media, hidden momentum and quantum phases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kholmetskii, Alexander L., E-mail: alkholmetskii@gmail.com; Missevitch, Oleg V.; Yarman, T.

We address to the force law in classical electrodynamics of material media, paying attention on the force term due to time variation of hidden momentum of magnetic dipoles. We highlight that the emergence of this force component is required by the general theorem, deriving zero total momentum for any static configuration of charges/currents. At the same time, we disclose the impossibility to add this force term covariantly to the Lorentz force law in material media. We further show that the adoption of the Einstein–Laub force law does not resolve the issue, because for a small electric/magnetic dipole, the density ofmore » Einstein–Laub force integrates exactly to the same equation, like the Lorentz force with the inclusion of hidden momentum contribution. Thus, none of the available expressions for the force on a moving dipole is compatible with the relativistic transformation of force, and we support this statement with a number of particular examples. In this respect, we suggest applying the Lagrangian approach to the derivation of the force law in a magnetized/polarized medium. In the framework of this approach we obtain the novel expression for the force on a small electric/magnetic dipole, with the novel expression for its generalized momentum. The latter expression implies two novel quantum effects with non-topological phases, when an electric dipole is moving in an electric field, and when a magnetic dipole is moving in a magnetic field. These phases, in general, are not related to dynamical effects, because they are not equal to zero, when the classical force on a dipole is vanishing. The implications of the obtained results are discussed.« less

Writing and Digital Media

ERIC Educational Resources Information Center

van Waes, Luuk, Ed.; Leijten, Marielle, Ed.; Neuwirth, Chris, Ed.

2006-01-01

Digital media has become an increasingly powerful force in modern society. This volume brings together outstanding European, American and Australian research in "writing and digital media" and explores its cognitive, social and cultural implications. In addition to presenting programs of original research by internationally known…

Effects of Sterilizing Agents on Microorganisms

DTIC Science & Technology

1963-03-01

light increases with the incubation of Escherichia coli at 15, but the rate of in- 85. ESTUDIO DE LOS EFECTOS QUE PRODUCE duction of mutations...between the deoxyribonucleic acid content of a cell and its response to irradiation: 5-fluor- 86. ESTUDIO DE LOS EFECTOS QUE PRODUCE ouracil treated...EFFECTS OF ULTRAVIOLET LIGHT ON 84. ESTUDIO DE LOS EFECTOS QUE PRODUCE BACTERIA. III. ALTERATIONS IN THE LA LUZ ULTRAVIOLETA SOBRE LAS PHYSIOLOGICAL

Power with Social Media: A Nursing Perspective.

PubMed

Milton, Constance L

2016-04-01

Power is an emanating force typically associated with personal relationships. With the expanding capacities and utilization of social media, power with media is an emerging ethical concern to the discipline of nursing. The author here discusses potential ethical meanings and implications of power with social media while utilizing technology in future nurse practice and education. © The Author(s) 2016.

Media as Nexus of Practice: Remaking Identities in "What Not to Wear"

ERIC Educational Resources Information Center

Wohlwend, Karen E.; Medina, Carmen L.

2012-01-01

In this conceptual piece, we examine media as a nexus of a traditional schooling pedagogy and performance pedagogy to make visible how their overlapping elements produce media's pervasive educative force but also to gain a deeper understanding of the complexities of using media in educational contexts. Nexus analysis examines a fashion makeover…

KSC-2015-1206

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Jason Townsend, NASA's deputy social media manager, addresses the audience of a NASA Social held at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

The effect of different environmental factors on force degradation of three common systems of orthodontic space closure.

PubMed

Oshagh, Morteza; Khajeh, Farzaneh; Heidari, Somayeh; Torkan, Sepideh; Fattahi, Hamid Reza

2015-01-01

Different environmental conditions, such as high temperature or exposure to some chemical agents, may affect the force decay of different methods of space closure during orthodontic treatment. The aim of this in vitro study was to evaluate the force decay pattern in the presence of tea as a popular drink in some parts of the world and two mouthwashes that are usually prescribed by the orthodontist once the treatment is in progress. Elastic chain (EC), nickel-titanium (Ni-Ti) closed coil spring and tie-back (TB) method were used as the means of space closure. The specimens were placed in five different media: Hot tea, hot water (65°), chlorhexidine mouthwash, fluoride mouthwash and the control group (water at 37°). The specimens were stretched 25 mm and the elastic force of three systems was measured at the beginning of the study, after 24 h, after 1 week and after 3 weeks. One-way ANOVA was used to compare the results between the groups and Duncan test was carried out to compare the sets of means in different groups (P ≤ 0.05). Tea increases the force decay in the EC and TB groups. Oral mouthwashes also resulted in more rapid force decay than the control group. EC and Ni-Ti groups were not much affected in the presence of oral mouthwashes. Regarding the immersion media, TB method showed the biggest variation in different media and Ni-Ti coil spring was least affected by the type of media.

The effect of different environmental factors on force degradation of three common systems of orthodontic space closure

PubMed Central

Oshagh, Morteza; Khajeh, Farzaneh; Heidari, Somayeh; Torkan, Sepideh; Fattahi, Hamid Reza

2015-01-01

Background: Different environmental conditions, such as high temperature or exposure to some chemical agents, may affect the force decay of different methods of space closure during orthodontic treatment. The aim of this in vitro study was to evaluate the force decay pattern in the presence of tea as a popular drink in some parts of the world and two mouthwashes that are usually prescribed by the orthodontist once the treatment is in progress. Materials and Methods: Elastic chain (EC), nickel-titanium (Ni-Ti) closed coil spring and tie-back (TB) method were used as the means of space closure. The specimens were placed in five different media: Hot tea, hot water (65°), chlorhexidine mouthwash, fluoride mouthwash and the control group (water at 37°). The specimens were stretched 25 mm and the elastic force of three systems was measured at the beginning of the study, after 24 h, after 1 week and after 3 weeks. One-way ANOVA was used to compare the results between the groups and Duncan test was carried out to compare the sets of means in different groups (P ≤ 0.05). Results: Tea increases the force decay in the EC and TB groups. Oral mouthwashes also resulted in more rapid force decay than the control group. EC and Ni-Ti groups were not much affected in the presence of oral mouthwashes. Conclusion: Regarding the immersion media, TB method showed the biggest variation in different media and Ni-Ti coil spring was least affected by the type of media. PMID:25709675

Historical Development of Media Systems. I. Japan. Communication and Society 1.

ERIC Educational Resources Information Center

Ito, Shinichi; And Others

This report presents an insight into indigenous media forms and the introduction of modern media in Japan, and follows media development through the war and occupation to the present day. The report discusses (1) the birth of the newspaper in Japan, (2) control laws and regulations, (3) press policy under the allied forces' occupation of Japan,…

Mass Media Forces in Our society. Second Edition.

ERIC Educational Resources Information Center

Voelker, Francis H.; Voelker, Ludmila A.

The primary purpose of this book is to help the public become more aware and critical in their selection and appraisal of the media. Part 1 consists of a single essay by Theodore Peterson that gives a historical perspective on the development of the mass media in the United States. Part 2 deals with the print and electronic media: magazines, photo…

Impacto del Seguro Popular en el gasto catastrófico y de bolsillo en el México rural y urbano, 2005–2008

PubMed Central

Sosa-Rubí, Sandra G; Salinas-Rodríguez, Aarón; Galárraga, Omar

2016-01-01

Objetivo Estimar el efecto del Seguro Popular (SP) sobre la incidencia del gasto catastrófico en salud (GCS) y sobre el gasto de bolsillo en salud (GBS) en el mediano plazo. Material y métodos Con base en la Encuesta de Evaluación del Seguro Popular (2005–2008), se analizaron los resultados del efecto del SP en la cohorte rural para dos años de seguimiento (2006 y 2008) y en la cohorte urbana para un año (2008). Resultados A nivel conglomerado no se detectaron efectos del SP. A nivel hogar se encontró que el SP tiene un efecto protector en el GCS y en el GBS en consulta externa y hospitalización en zonas rurales; y efectos significativos en la reducción de GBS en consulta externa en zonas urbanas. Conclusiones El SP se muestra como un programa efectivo para proteger a los hogares contra gastos de bolsillo por motivos de salud en el mediano plazo. PMID:22282205

Enhanced solar evaporation of water from porous media, through capillary mediated forces and surface treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Canbazoglu, F. M.; Fan, B.; Kargar, A.

2016-08-15

The relative influence of the capillary, Marangoni, and hydrophobic forces in mediating the evaporation of water from carbon foam based porous media, in response to incident solar radiation, are investigated. It is indicated that inducing hydrophilic interactions on the surface, through nitric acid treatment of the foams, has a similar effect to reduced pore diameter and the ensuing capillary forces. The efficiency of water evaporation may be parameterized through the Capillary number (Ca), with a lower Ca being preferred. The proposed study is of much relevance to efficient solar energy utilization.

Joint Chiefs of Staff > Media

Science.gov Websites

Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Joint Staff Media News Videos Chairman's

Gulf Coast Ecosystem Restoration Task Force Meeting and Public Listening

Science.gov Websites

Data Media & News Publications Press Releases Story Archive Home Gulf Coast Ecosystem Restoration Task Force Meeting and Public Listening Session Gulf Coast Ecosystem Restoration Task Force Meeting and Title: Gulf Coast Ecosystem Restoration Task Force Meeting and Public Listening SessionDescription: The

HOW THE ARMY NATIONAL GUARD CAN LEVERAGE SOCIAL MEDIA TO INCREASE VISIBILITY AND RECRUTING

DTIC Science & Technology

2016-02-16

will research how each branch of service is using social media platforms to reach the desired audience and have a recommendation for the National...ensure the Air Force is reaching the right demographics for their target audience . The Air Force Recruiting Facebook page reflects what the advertising...outreach efforts that are distinct from—yet integral to—those of the Services. JAMRS creates a receptive recruiting environment by building awareness

Sexual misbehaviour in the Australian Defence Force.

PubMed

Williams, Angela; Ranson, David

2013-12-01

It is clear from recent media reporting that serious issues have come to light regarding sexual misbehaviour matters within the Australian Defence Force. Subsequent reviews have indicated that these behaviours appear to have been more widespread than the initial media reports suggested and a number of reviews have been undertaken to better understand the problem and address the concerns of victims, Defence command, government and the community. If these problems are not addressed, there is a risk that recruitment to the Defence Forces may become problematic. The strong command structures within the Defence Forces can both exacerbate these misbehaviours through entrenching secrecy and at the same time have the capacity to provide a powerful leadership message that can change attitudes and reduce such misbehaviours.

The War in Man; Media and Machines.

ERIC Educational Resources Information Center

Wilhelmsen, Frederick D.; Bret, Jane

The authors present a picture of contemporary man torn by conflicting forces, caught in a psychic house divided against itself, a victim of war between media and machines. Machines, they state, represent the rationalistic tradition which has brought man to the brink of psychic and social disaster. The media they see as offering hope--true…

New Media Literacy: From Classroom to Community.

ERIC Educational Resources Information Center

Carstarphen, Meta G.

Each new media revolution forces adjustments for both the producers of messages and the receivers of those messages. Integral to the communication process is an understanding of what it means to be literate in an eclectic communication environment and of how the new media may enhance or impede literacy. An important premise for this discussion is…

Forced imbibition through model porous media

NASA Astrophysics Data System (ADS)

Odier, Celeste; Levache, Bertrand; Bartolo, Denis

2016-11-01

A number of industrial and natural process ultimately rely on two-phase flow in heterogeneous media. One of the most prominent example is oil recovery which has driven fundamental and applied research in this field for decades. Imbibition occurs when a wetting fluid displaces an immiscible fluid e.g. in a porous media. Using model microfluidic experiment we control both the geometry and wetting properties of the heterogenous media, and show that the typical front propagation picture fails when imbibition is forced and the displacing fluid is less viscous than the non-wetting fluid. We identify and quantitatively characterize four different flow regimes at the pore scale yielding markedly different imbibition patterns at large scales. In particular we will discuss the transition from a conventional 2D-front propagation scenario to a regime where the meniscus dynamics is an intrinsically 3D process.

Money Laundering in China: Why PACOM Should Place High Priority on this Issue

DTIC Science & Technology

2012-10-06

Financial Action Task Force ( FATF ), a multi-national organization responsible for anti-money laundering (AML) regulation and enforcement standards...29, 2007, 7. www.fatf- gafi.org/media/ fatf /documents/reports/mer/MER%20China%20full.pdf Accessed on 12Sep12. 14 George W. Russell, “Dirty Money...Evaluation, 8 th Follow-up Report, Financial Action Task Force, February 17, 2012. www.fatf- gafi.org/media/ fatf /documents/reports/mer/Follow%20Up

Scaling down constriction-based (electrodeless) dielectrophoresis devices for trapping nanoscale bioparticles in physiological media of high-conductivity.

PubMed

Chaurey, Vasudha; Rohani, Ali; Su, Yi-Hsuan; Liao, Kuo-Tang; Chou, Chia-Fu; Swami, Nathan S

2013-04-01

Selective trapping of nanoscale bioparticles (size <100 nm) is significant for the separation and high-sensitivity detection of biomarkers. Dielectrophoresis is capable of highly selective trapping of bioparticles based on their characteristic frequency response. However, the trapping forces fall steeply with particle size, especially within physiological media of high-conductivity where the trapping can be dissipated by electrothermal (ET) flow due to localized Joule heating. Herein, we investigate the influence of device scaling within the electrodeless insulator dielectrophoresis geometry through the application of highly constricted channels of successively smaller channel depth, on the net balance of dielectrophoretic trapping force versus ET drag force on bioparticles. While higher degrees of constriction enable dielectrophoretic trapping of successively smaller bioparticles within a short time, the ETflow due to enhanced Joule heating within media of high conductivity can cause a significant dissipation of bioparticle trapping. This dissipative drag force can be reduced through lowering the depth of the highly constricted channels to submicron sizes, which substantially reduces the degree of Joule heating, thereby enhancing the range of voltages and media conductivities that can be applied toward rapid dielectrophoretic concentration enrichment of silica nanoparticles (∼50 nm) and streptavidin protein biomolecules (∼5 nm). We envision the application of these methodologies toward nanofabrication, optofluidics, biomarker discovery, and early disease diagnostics. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Microgravity effects on water flow and distribution in unsaturated porous media: Analyses of flight experiments

NASA Astrophysics Data System (ADS)

Jones, Scott B.; Or, Dani

1999-04-01

Plants grown in porous media are part of a bioregenerative life support system designed for long-duration space missions. Reduced gravity conditions of orbiting spacecraft (microgravity) alter several aspects of liquid flow and distribution within partially saturated porous media. The objectives of this study were to evaluate the suitability of conventional capillary flow theory in simulating water distribution in porous media measured in a microgravity environment. Data from experiments aboard the Russian space station Mir and a U.S. space shuttle were simulated by elimination of the gravitational term from the Richards equation. Qualitative comparisons with media hydraulic parameters measured on Earth suggest narrower pore size distributions and inactive or nonparticipating large pores in microgravity. Evidence of accentuated hysteresis, altered soil-water characteristic, and reduced unsaturated hydraulic conductivity from microgravity simulations may be attributable to a number of proposed secondary mechanisms. These are likely spawned by enhanced and modified paths of interfacial flows and an altered force ratio of capillary to body forces in microgravity.

The effectiveness of resistive force theory in granular locomotiona)

NASA Astrophysics Data System (ADS)

Zhang, Tingnan; Goldman, Daniel I.

2014-10-01

Resistive force theory (RFT) is often used to analyze the movement of microscopic organisms swimming in fluids. In RFT, a body is partitioned into infinitesimal segments, each of which generates thrust and experiences drag. Linear superposition of forces from elements over the body allows prediction of swimming velocities and efficiencies. We show that RFT quantitatively describes the movement of animals and robots that move on and within dry granular media (GM), collections of particles that display solid, fluid, and gas-like features. RFT works well when the GM is slightly polydisperse, and in the "frictional fluid" regime such that frictional forces dominate material inertial forces, and when locomotion can be approximated as confined to a plane. Within a given plane (horizontal or vertical) relationships that govern the force versus orientation of an elemental intruder are functionally independent of the granular medium. We use the RFT to explain features of locomotion on and within granular media including kinematic and muscle activation patterns during sand-swimming by a sandfish lizard and a shovel-nosed snake, optimal movement patterns of a Purcell 3-link sand-swimming robot revealed by a geometric mechanics approach, and legged locomotion of small robots on the surface of GM. We close by discussing situations to which granular RFT has not yet been applied (such as inclined granular surfaces), and the advances in the physics of granular media needed to apply RFT in such situations.

KSC-2015-1220

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Representatives of the social media were given the opportunity to ask questions from the experts of NASA's Soil Moisture Active Passive mission, or SMAP, at the NASA Social held at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

Analysis of capacitive force acting on a cantilever tip at solid/liquid interfaces

NASA Astrophysics Data System (ADS)

Umeda, Ken-ichi; Kobayashi, Kei; Oyabu, Noriaki; Hirata, Yoshiki; Matsushige, Kazumi; Yamada, Hirofumi

2013-04-01

Dielectric properties of biomolecules or biomembranes are directly related to their structures and biological activities. Capacitance force microscopy based on the cantilever deflection detection is a useful scanning probe technique that can map local dielectric constant. Here we report measurements and analysis of the capacitive force acting on a cantilever tip at solid/liquid interfaces induced by application of an alternating voltage to explore the feasibility of the measurements of local dielectric constant by the voltage modulation technique in aqueous solutions. The results presented here suggest that the local dielectric constant measurements by the conventional voltage modulation technique are basically possible even in polar liquid media. However, the cantilever deflection is not only induced by the electrostatic force, but also by the surface stress, which does not include the local dielectric information. Moreover, since the voltage applied between the tip and sample are divided by the electric double layer and the bulk polar liquid, the capacitive force acting on the apex of the tip are strongly attenuated. For these reasons, the lateral resolution in the local dielectric constant measurements is expected to be deteriorated in polar liquid media depending on the magnitude of dielectric response. Finally, we present the criteria for local dielectric constant measurements with a high lateral resolution in polar liquid media.

Citizen Airman Magazine > Home

Science.gov Websites

Past Issues Social Media Twitter Logo Youth aviation event sparks new energy - https://t.co/TJG3nKAs4D ! Just getting things setup! Facebook 76 Like Us Twitter 278 Follow Us YouTube Blog RSS Air Force Social Media Guide (PDF) USAF Social Media Sites About AFRC AFR Mission Briefing Mission Briefing AFR Snapshot

The Status of Mass Media Coverage of Campaign '80.

ERIC Educational Resources Information Center

Larson, Charles U.

Some of the similarities and differences in the news media coverage of the United States presidential campaign of 1980 are discussed in this paper. Among the differences related are the loss of the symbolic power of tbe primary elections, which forced the media to look for significant trends elsewhere; the mixture of politics with the…

Transition of torque pattern in undulatory locomotion due to wave number variation in resistive force dominated media

NASA Astrophysics Data System (ADS)

Ding, Yang; Ming, Tingyu

2016-11-01

In undulatory locomotion, torque (bending moment) is required along the body to overcome the external forces from environments and bend the body. Previous observations on animals using less than two wavelengths on the body showed such torque has a single traveling wave pattern. Using resistive force theory model and considering the torque generated by external force in a resistive force dominated media, we found that as the wave number (number of wavelengths on the locomotor's body) increases from 0.5 to 1.8, the speed of the traveling wave of torque decreases. When the wave number increases to 2 and greater, the torque pattern transits from a single traveling wave to a two traveling waves and then a complex pattern that consists two wave-like patterns. By analyzing the force distribution and its contribution to the torque, we explain the speed decrease of the torque wave and the pattern transition. This research is partially supported by the Recruitment Program of Global Young Experts (China).

Boys to Men: Entertainment Media. Messages about Masculinity: A National Poll of Children, Focus Groups, and Content Analysis of Entertainment Media.

ERIC Educational Resources Information Center

Heintz-Knowles, Katharine; Li-Vollmer, Meredith; Chen, Perry; Harris, Tarana; Haufler, Adrienne; Lapp, Joan; Miller, Patti

Boys are especially active users of media, and researchers have suggested that the cumulative impact of media, such as television, movies, and music videos, may make them some of the most influential forces in boys' lives. This report presents the findings of a national poll of 1,200 young people (ages 10 to 17) and focus groups in which boys…

The Information Revolution and International Communication

ERIC Educational Resources Information Center

Day, Donald L.

1975-01-01

As a result of the growth of media, the onrushing Information Revolution has forced man into a new era - an era in which the study of media and their effects is prerequisite to understanding interaction among people. (Author)

Defense.gov Special Report: CENTCOM

Science.gov Websites

U.S. Air Force National Guard U.S. Coast Guard All DOD Sites Military/DOD Social Media Sites Register : Email Email Icon: RSS Feeds RSS Feeds Icon: Widgets Widgets MORE SOCIAL MEDIA SITES »

Vibration damping of elastic waves in electrically conducting media subjected to high magnetic fields

NASA Technical Reports Server (NTRS)

Horwath, T. G.

1992-01-01

The propagation of vibrational energy in bulk, torsional, and flexural modes, in electrically conducting media can undergo strong attenuation if subjected to high magnetic fields in certain spatial arrangements. The reasons for this are induced Eddy currents which are generated by the volume elements in the media moving transversally to the magnetic field at acoustic velocities. In magnetic fields achievable with superconductors, the non-conservative (dissipative) forces are compared to the elastic and inertial forces for most metals. Strong dissipation of vibrational energy in the form of heat takes place as a result. A simplified theory is presented based on engineering representations of electrodynamics, attenuation values for representative metals are calculated, and problems encountered in formulating a generalized theory based on electrodynamics of moving media are discussed. General applications as well as applications specific to maglev are discussed.

Translation and Rotation of Transformation Media under Electromagnetic Pulse

PubMed Central

Gao, Fei; Shi, Xihang; Lin, Xiao; Xu, Hongyi; Zhang, Baile

2016-01-01

It is well known that optical media create artificial geometry for light, and curved geometry acts as an effective optical medium. This correspondence originates from the form invariance of Maxwell’s equations, which recently has spawned a booming field called ‘transformation optics’. Here we investigate responses of three transformation media under electromagnetic pulses, and find that pulse radiation can induce unbalanced net force on transformation media, which will cause translation and rotation of transformation media although their final momentum can still be zero. Therefore, the transformation media do not necessarily stay the same after an electromagnetic wave passes through. PMID:27321246

Translation and Rotation of Transformation Media under Electromagnetic Pulse.

PubMed

Gao, Fei; Shi, Xihang; Lin, Xiao; Xu, Hongyi; Zhang, Baile

2016-06-20

It is well known that optical media create artificial geometry for light, and curved geometry acts as an effective optical medium. This correspondence originates from the form invariance of Maxwell's equations, which recently has spawned a booming field called 'transformation optics'. Here we investigate responses of three transformation media under electromagnetic pulses, and find that pulse radiation can induce unbalanced net force on transformation media, which will cause translation and rotation of transformation media although their final momentum can still be zero. Therefore, the transformation media do not necessarily stay the same after an electromagnetic wave passes through.

Role of air-water interfaces in colloid transport in porous media: A review

NASA Astrophysics Data System (ADS)

Flury, Markus; Aramrak, Surachet

2017-07-01

Air-water interfaces play an important role in unsaturated porous media, giving rise to phenomena like capillarity. Less recognized and understood are interactions of colloids with the air-water interface in porous media and the implications of these interactions for fate and transport of colloids. In this review, we discuss how colloids, both suspended in the aqueous phase and attached at pore walls, interact with air-water interfaces in porous media. We discuss the theory of colloid/air-water interface interactions, based on the different forces acting between colloids and the air-water interface (DLVO, hydrophobic, capillary forces) and based on thermodynamic considerations (Gibbs free energy). Subsurface colloids are usually electrostatically repelled from the air-water interface because most subsurface colloids and the air-water are negatively charged. However, hydrophobic interactions can lead to attraction to the air-water interface. When colloids are at the air-water interface, capillary forces are usually dominant over other forces. Moving air-water interfaces are effective in mobilizing and transporting colloids from surfaces. Thermodynamic considerations show that, for a colloid, the air-water interface is the favored state as compared with the suspension phase, except for hydrophilic colloids in the nanometer size range. Experimental evidence indicates that colloid mobilization in soils often occurs through macropores, although matrix transport is also prevalent in absence of macropores. Moving air-water interfaces, e.g., occurring during infiltration, imbibition, or drainage, have been shown to scour colloids from surfaces and translocate colloids. Colloids can also be pinned to surfaces by thin water films and capillary menisci at the air-water-solid interface line, causing colloid retention and immobilization. Air-water interfaces thus can both mobilize or immobilize colloids in porous media, depending on hydrodynamics and colloid and surface chemistry.

Efectos Especiales de Anclaje (Estudio sobre Regresiones de Juicios Condicionales). Parte 1: Distincion entre Efectos Aditivos y Efectos Multiplicativos en el Fenomeno de Anclaje (Special Effects of Anchoring (Study on Regression of Conditional Judgements) Part 1: Distinction Between Additive Effects and Multiplicative Effects in the Phenomenon of Anchoring). Publication No. 17.

ERIC Educational Resources Information Center

Lopez Alonso, A. O.

A linear relationship was found between judgements given by 160 subjects to 7 objects presented as single stimuli (alpha judgements) and judgements given to the same objects presented with a condition (gamma judgements). This relationship holds for alpha judgements and the gamma judgements that belong to a family of constant stimulus and varying…

Bipedal locomotion in granular media

NASA Astrophysics Data System (ADS)

Kingsbury, Mark; Zhang, Tingnan; Goldman, Daniel

Bipedal walking, locomotion characterized by alternating swing and double support phase, is well studied on ground where feet do not penetrate the substrate. On granular media like sand however, intrusion and extrusion phases also occur. In these phases, relative motion of the two feet requires that one or both feet slip through the material, degrading performance. To study walking in these phases, we designed and studied a planarized bipedal robot (1.6 kg, 42 cm) that walked in a fluidized bed of poppy seeds. We also simulated the robot in a multibody software environment (Chrono) using granular resistive force theory (RFT) to calculate foot forces. In experiment and simulation, the robot experienced slip during the intrusion phase, with the experiment presenting additional slip due to motor control error during the double support phase. This exaggerated slip gave insight (through analysis of ground reaction forces in simulation) into how slip occurs when relative motion exists between the two feet in the granular media, where the foot with higher relative drag forces (from its instantaneous orientation, rotation, relative direction of motion, and depth) remains stationary. With this relationship, we generated walking gaits for the robot to walk with minimal slip.

Adherence to the Otitis Media with Effusion Clinical Practice Guideline by Providers in a United States Air Force Medical Treatment Facility

DTIC Science & Technology

1999-05-07

making. The United States Agency for Health Care Policy and Research published the Otitis Media with Effusion (OME) in Young Children Clinical Practice...diagnosed with otitis media were audited using a checklist developed from the treatment algorithm. Twenty-three of these children had OME. Using summary...of pneumatic otoscopy and/or tympanometry to evaluate the tympanic membrane for OME and acute otitis media .

The Predictive Level of Social Media Addiction for Life Satisfaction: A Study on University Students

ERIC Educational Resources Information Center

Sahin, Cengiz

2017-01-01

Social media addiction is considered as a sort of Internet addiction. Individuals who spend too much time on social media have a desire to be notified of anything immediately, which can cause virtual tolerance, virtual communication and virtual problems. Behaviours that force the person into these actions can be explained as social media…

Past lessons and new uses of the mass media in reducing tobacco consumption.

PubMed

Erickson, A C; McKenna, J W; Romano, R M

1990-01-01

A review of mass media response to the smoking issue over the past 25 years reveals that sustained involvement of the broadcast and print media has served significantly to heighten public awareness and reduce smoking rates in the total U.S. population. Public service advertising has been an integral part of the smoking control movement from its outset, but today's intensely competitive media environment has forced health promoters to look beyond public service announcements in the development of total communication programs. Media advocacy--using the media to sharpen public awareness and mold public policy to serve the public interest, a technique derived from political campaigns--is emerging as a powerful tool in the smoking control movement. Its emphasis is on changing the entire social context of tobacco use in America, rather than the smoking behavior of people. Because media advocates' success pivots on their access to the media, they must be able both to create news and to react quickly to breaking news and unexpected events. The opportunistic, risk-taking nature of media advocacy requires that most efforts be waged at the State and local levels. An increasing number of State health departments and other organizations are using paid advertising to improve the frequency and reach of nonsmoking messages. Research verifies that paid media campaigns increase the target audience's exposure to smoking control messages, but planning and making efficient media purchases require sophistication and, of course, the necessary funds. Irrefutable medical evidence linking smoking to disease and addiction, combined with the powerful social force of the nonsmokers' rights movement, offer hope that a smoke-free society is an achievable goal. Success,however, will only be realized if tobacco control activists make use of the full range of mass media technologies to sustain and nourish this momentum.

Self-organization of granular media in airborne ultrasonic fields

NASA Astrophysics Data System (ADS)

Bobrovskaya, A. I.; Stepanenko, D. A.; Minchenya, V. T.

2012-05-01

The article presents results of experimental and theoretical studies of behaviour of granular media (powder materials) in airborne ultrasonic field created by flexurally-vibrating ring-shaped waveguide with resonant frequency in the range 20-40 kHz. Experiments show that action of acoustic radiation forces results in formation of ordered structures in the form of ultrathin walls (monolayers) with number corresponding to the number of ring nodal points. Action of secondary radiation forces (König forces) results in formation of collateral (secondary) walls situated nearby primary walls. Experimental observations are compared with results of modelling of acoustic radiation force field inside the ring by means of COMSOL Multiphysics and MathCad software. Results of the studies can be used in development of devices for ultrasonic separation and concentration of particles as well as for formation of ordered monolayers from spherical particles.

Defense.gov Special Report: The Cyber Domain - Security and Operations

Science.gov Websites

U.S. Air Force National Guard U.S. Coast Guard All DOD Sites Military/DOD Social Media Sites Register : Email Email Icon: RSS Feeds RSS Feeds Icon: Widgets Widgets MORE SOCIAL MEDIA SITES »

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Jason Townsend, NASA's Deputy Social Media Manager, reads questions submitted by online social media followers during a prelaunch media briefing for NASA's InSight mission, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

Past lessons and new uses of the mass media in reducing tobacco consumption.

PubMed Central

Erickson, A C; McKenna, J W; Romano, R M

1990-01-01

A review of mass media response to the smoking issue over the past 25 years reveals that sustained involvement of the broadcast and print media has served significantly to heighten public awareness and reduce smoking rates in the total U.S. population. Public service advertising has been an integral part of the smoking control movement from its outset, but today's intensely competitive media environment has forced health promoters to look beyond public service announcements in the development of total communication programs. Media advocacy--using the media to sharpen public awareness and mold public policy to serve the public interest, a technique derived from political campaigns--is emerging as a powerful tool in the smoking control movement. Its emphasis is on changing the entire social context of tobacco use in America, rather than the smoking behavior of people. Because media advocates' success pivots on their access to the media, they must be able both to create news and to react quickly to breaking news and unexpected events. The opportunistic, risk-taking nature of media advocacy requires that most efforts be waged at the State and local levels. An increasing number of State health departments and other organizations are using paid advertising to improve the frequency and reach of nonsmoking messages. Research verifies that paid media campaigns increase the target audience's exposure to smoking control messages, but planning and making efficient media purchases require sophistication and, of course, the necessary funds. Irrefutable medical evidence linking smoking to disease and addiction, combined with the powerful social force of the nonsmokers' rights movement, offer hope that a smoke-free society is an achievable goal.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2113681

E. coli interactions, adhesion and transport in alumino-silica clays.

PubMed

Wei, Houzhen; Yang, Guang; Wang, Boya; Li, Runwei; Chen, Gang; Li, Zhenze

2017-06-01

Bacterial adhesion and transport in the geological formation are controlled by their mutual complex interactions, which have been quantified by the traditional and extended Derjaguin-Landau-Verwey-Overbeek (DLVO) theory as well as direct atomic force microscopy (AFM) measurements. In this research, the DLVO forces calculated based on the independently determined bacterial and porous media surface thermodynamic properties were compared with those of AFM measurements. Although differences in the order of several magnitudes existed, forces obtained from both ways could explain the observations of E. coli attachment to alumino-silica clays evaluated in laboratory columns under saturated and steady-state flow conditions. E. coli deposition in alumino-silica clays was simulated using a two-site convection-dispersion transport model against E. coli transport breakthrough curves, which was then linked to the interactions forces. By exploring the differences of the two force measurements, it was concluded that the thermodynamic calculations could complement the direct force measurements in describing bacterial interactions with the surrounding environment and the subsequent transport in the porous media. Published by Elsevier B.V.

Low-resistive penetration in granular media

NASA Astrophysics Data System (ADS)

Darbois Texier, Baptiste; Ibarra, Alejandro; Melo, Fransisco

The quasi-static immersion of an intruder into a granular assembly requires a force that is several orders of magnitude larger than necessary in fluids under similar conditions. This occurs as a result of the progressive formation of a network composed of force chains, which simultaneously increase in size with intruder penetration. The present work shows that the resisting force for the immersion of an intruder into a granular material can be reduced by an order of magnitude with mechanical vibrations of small amplitude (A = 10 μm) and low frequency (f = 50-200 Hz). The effect of the vibrations characteristics and the intruder geometry on the drop of the resistive force were inspected experimentally. Thanks to flow visualizations, it has been shown that vibrations induce a local convection into the granular media leading to the modification of the network of force chains. Moreover, scaling arguments are developed in order to rationalize our observations and to predict under which circumstances the resistive force is reduced. Finally, the use of such a phenomenon in the animal kingdom and the technological world will be discussed.

How well can an amoeba climb?

PubMed Central

Fukui, Yoshio; Uyeda, Taro Q. P.; Kitayama, Chikako; Inoué, Shinya

2000-01-01

We report here our efforts to measure the crawling force generated by cells undergoing amoeboid locomotion. In a centrifuge microscope, acceleration was increased until amoebae of Dictyostelium discoideum were “stalled” or no longer able to “climb up.” The “apparent weight” of the amoebae at stalling rpm in myosin mutants depended on the presence of myosin II (but not myosins IA and IB) and paralleled the cortical strength of the cells. Surprisingly, however, the cell stalled not only in low-density media as expected but also in media with densities greater than the cell density where the buoyant force should push the amoeba upward. We find that the leading pseudopod is bent under centrifugal force in all stalled amoebae, suggesting that this pseudopod is very dense indeed. This finding also suggests that directional cell locomotion against resistive forces requires a turgid forward-pointing pseudopod, most likely sustained by cortical actomyosin II. PMID:10963666

Astronaut Virgil Grissom and family at Patrick AFB airport

NASA Image and Video Library

1961-07-21

S61-03687 (21 July 1961) --- Astronaut Virgil I. (Gus) Grissom and his family are shown at the airport at Patrick Air Force Base facing a crowd of news media representatives. Grissom is speaking into microphones for the news media. Photo credit: NASA

Radiological contrast media in the breastfeeding woman: a position paper of the Italian Society of Radiology (SIRM), the Italian Society of Paediatrics (SIP), the Italian Society of Neonatology (SIN) and the Task Force on Breastfeeding, Ministry of Health, Italy.

PubMed

Cova, Maria Assunta; Stacul, Fulvio; Quaranta, Roberto; Guastalla, Pierpaolo; Salvatori, Guglielmo; Banderali, Giuseppe; Fonda, Claudio; David, Vincenzo; Gregori, Massimo; Zuppa, Antonio Alberto; Davanzo, Riccardo

2014-08-01

Breastfeeding is a well-recognised investment in the health of the mother-infant dyad. Nevertheless, many professionals still advise breastfeeding mothers to temporarily discontinue breastfeeding after contrast media imaging. Therefore, we performed this review to provide health professionals with basic knowledge and skills for appropriate use of contrast media. A joint working group of the Italian Society of Radiology (SIRM), Italian Society of Paediatrics (SIP), Italian Society of Neonatology (SIN) and Task Force on Breastfeeding, Ministry of Health, Italy prepared a review of the relevant medical literature on the safety profile of contrast media for the nursing infant/child. Breastfeeding is safe for the nursing infant of any post-conceptional age after administration of the majority of radiological contrast media to the mother; only gadolinium-based agents considered at high risk of nephrogenic systemic fibrosis (gadopentetate dimeglumine, gadodiamide, gadoversetamide) should be avoided in the breastfeeding woman as a precaution; there is no need to temporarily discontinue breastfeeding or to express and discard breast milk following the administration of contrast media assessed as compatible with breastfeeding. Breastfeeding women should receive unambiguous professional advice and clear encouragement to continue breastfeeding after imaging with the compatible contrast media. • Breastfeeding is a well-known investment in the health of the mother-infant dyad. • Breastfeeding is safe after administration of contrast media to the mother. • There is no need to temporarily discontinue breastfeeding following administration of contrast media.

Children, Adolescents, and the Media.

PubMed

2013-11-01

Media, from television to the "new media" (including cell phones, iPads, and social media), are a dominant force in children's lives. Although television is still the predominant medium for children and adolescents, new technologies are increasingly popular. The American Academy of Pediatrics continues to be concerned by evidence about the potential harmful effects of media messages and images; however, important positive and prosocial effects of media use should also be recognized. Pediatricians are encouraged to take a media history and ask 2 media questions at every well-child visit: How much recreational screen time does your child or teenager consume daily? Is there a television set or Internet-connected device in the child's bedroom? Parents are encouraged to establish a family home use plan for all media. Media influences on children and teenagers should be recognized by schools, policymakers, product advertisers, and entertainment producers. Copyright © 2013 by the American Academy of Pediatrics.

How Older People Think about Images of Aging in Advertising and the Media.

ERIC Educational Resources Information Center

Bradley, Don E.; Longino, Charles F., Jr.

2001-01-01

A literature review documents distorted images of aging in mass media and advertising, including underrepresentation and stereotyping. Older consumers are dissatisfied with these images, and their growing purchasing power is forcing advertisers to make more effective appeals. (Contains 20 references.) (SK)

Protecting Children and Supporting Families.

ERIC Educational Resources Information Center

Wolf, Kathy Goetz, Ed.

1997-01-01

This serial "double issue" focuses on protecting children and supporting families through greater collaboration between child welfare services and family resource programs. The issue includes the featured articles: (1) "Making the Media a Constructive Force in Child Welfare" (Kathy Bonk), which discusses how the media and child welfare agencies…

Coverage That Counts.

ERIC Educational Resources Information Center

Moss, Nancy

1990-01-01

As the shrinking pool of applicants forces colleges to adapt new approaches to recruiting, media campaigns are emerging as an effective way to send key messages to target audiences. Media relations can lend credibility (news coverage is considered more credible than advertising); save money; reach targeted areas; and communicate key themes. (MLW)

Trolling New Media: Violent Extremist Groups Recruiting Through Social Media

DTIC Science & Technology

2015-12-01

MASTER OF ARTS IN SECURITY STUDIES (HOMELAND SECURITY AND DEFENSE) from the NAVAL POSTGRADUATE SCHOOL December 2015 Approved by...55 B. COUNTERTERRORISM EFFORTS ...................................................58 C. FUTURE AREAS OF STUDY ...Kuffar video .....................26 Figure 4. Player from Under Ash assaulting military forces .....................................32 Figure 5

Special Operations Forces During the Dhofar Insurgency and in Afghanistan: A Comparative Study for German Special Operations Forces

DTIC Science & Technology

2011-04-28

rebels’ communist atheism formed unity among the counterinsurgents at the tactical level. The British SOF and the host nation’s indigenous forces...government that first had to be established and now develops its legitimacy. The communist atheism and the Sultan’s restrictive Media campaign

Adherence to the Otitis Media with Effusion Clinical Practice Guideline By Providers in a United States Air Force Medical Treatment Facility

DTIC Science & Technology

1999-03-18

In the United States, office visits for otitis media increased by 150 percent between 1975 and 1990, to 24.5 million (annually), with children under...visits for otitis media , they also had the greatest increase in number of visits between 1975 and 1990: 224 percent. Of significance, is the increase in...expenditure. Gates (1996) estimated the costs to be about five billion dollars annually. Cost is not the only factor important in the management of otitis media with

Gas fluidized-bed stirred media mill

DOEpatents

Sadler, III, Leon Y.

1997-01-01

A gas fluidized-bed stirred media mill is provided for comminuting solid ticles. The mill includes a housing enclosing a porous fluidizing gas diffuser plate, a baffled rotor and stator, a hollow drive shaft with lateral vents, and baffled gas exhaust exit ports. In operation, fluidizing gas is forced through the mill, fluidizing the raw material and milling media. The rotating rotor, stator and milling media comminute the raw material to be ground. Small entrained particles may be carried from the mill by the gas through the exit ports when the particles reach a very fine size.

KSC-2014-3053

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Representatives of social media outlets are welcomed to Vandenberg Air Force Base in California for the launch of NASA's Orbiting Carbon Observatory-2, or OCO-2, by John Yembrick, NASA's social media manager. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

The importance of media roughness considerations for describing particle deposition in porous media

NASA Astrophysics Data System (ADS)

Jin, C.; Emelko, M.

2016-12-01

The morphology of media/collector surfaces (i.e., roughness) is one of the most important factors that has been recognized for decades; however, literature has been, for the most part, contradictory, non-mechanistic, and non-quantitative. A one-site kinetic model for attachment/detachment using a convection-diffusion model was used to evaluate particle deposition on collector surfaces in the packed beds. Rigorous controlled experiments addressing the impacts of surface roughness on particle deposition were conducted in parallel plate and packed bed systems; they demonstrated that a) surface roughness consistently influenced colloid deposition in a nonlinear, non-monotonic manner such that a critical roughness size associated with minimum particle deposition could be identified and b) collector surface roughness and background ionic strength concurrently influenced particle deposition. Excellent agreement between experimental data and numerical simulations was found when the most current knowledge representing hydrodynamic and interfacial forces associated with collector media roughness was represented. Although surface roughness also had a non-linear, non-monotonic impact on DLVO interaction energy at all separation distances, it was inadequate for describing and simulating particle deposition on surfaces with variable roughness. Notably, this work demonstrates that hydrodynamic effects can significantly alter particle deposition relative to expectations when only the DLVO force is considered. Moreover, the combined effects of hydrodynamics and interaction forces on particle deposition on rough, spherical media are not additive, but synergistic. Consideration of hydrodynamic contributions to particle deposition may help to explain discrepancies between model-based expectations and experimental outcomes and improve descriptions of particle deposition during physicochemical filtration in systems with non-smooth collector surfaces.

A biphasic approach for the study of lift generation in soft porous media

NASA Astrophysics Data System (ADS)

Wu, Qianhong; Santhanam, Sridhar; Nathan, Rungun; Wang, Qiuyun

2017-04-01

Lift generation in highly compressible porous media under rapid compression continues to be an important topic in porous media flow. Although significant progress has been made, how to model different lifting forces during the compression process remains unclear. This is mainly because the input parameters of the existing theoretical studies, including the Darcy permeability of the porous media and the viscous damping coefficient of its solid phase, were manually adjusted so as to match the experimental data. In the current paper, we report a biphasic approach to experimentally and theoretically treat this limitation. Synthetic fibrous porous materials, whose permeability were precisely measured, were subsequently exposed to sudden impacts using a porous-walled cylinder-piston apparatus. The obtained time-dependent compression of the porous media, along with the permeability data, was applied in two different theoretical models to predict the pore pressure generation, a plug flow model and a consolidation model [Q. Wu et al., J. Fluid Mech. 542, 281 (2005a)]. Comparison between the theory and the experiments on the pore pressure distribution proved the validity of the consolidation model. Furthermore, a viscoelastic model, containing a nonlinear spring in conjunction with a linear viscoelastic generalized Maxwell mechanical module, was developed to characterize the solid phase lifting force. The model matched the experimental data very well. The paper presented herein, as one of the series studies on this topic, provides an important biphasic approach to characterize different forces that contribute to the lift generation in a soft porous medium under rapid compression.

Children's Media Culture in the New Millennium: Mapping the Digital Landscape.

ERIC Educational Resources Information Center

Montgomery, Kathryn C.

2000-01-01

Describes technological, demographic, and market forces shaping the new digital media culture and the various Web sites being created for children and teens, explaining how heavily-promoted commercial sites overshadow educational sites. Discusses efforts to create safe Internet zones for children. Recommends actions to promote development of a…

NASA Social and Media Briefing on Next Mars Mission

NASA Image and Video Library

2018-05-03

News media and social media participants gathered at Vandenberg Air Force Base in Central California Thursday, May 3 to hear from NASA and its partners about the agency’s mission to study the interior of the Red Planet. NASA’s Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) is scheduled to launch May 5 on a United Launch Alliance Atlas V rocket, from Space Launch Complex 3 at Vandenberg.

Analyst Performance Measures. Volume 1: Persistent Surveillance Data Processing, Storage and Retrieval

DTIC Science & Technology

2011-09-01

solutions to address these important challenges . The Air Force is seeking innovative architectures to process and store massive data sets in a flexible...Google Earth, the Video LAN Client ( VLC ) media player, and the Environmental Systems Research Institute corporation‘s (ESRI) ArcGIS product — to...Earth, Quantum GIS, VLC Media Player, NASA WorldWind, ESRI ArcGIS and many others. Open source GIS and media visualization software can also be

Properties of pseudo magnetism acting between bodies

NASA Astrophysics Data System (ADS)

Deva, Anish; Baruah, Abhinav Ray; Sarma, Arun

A non-contact force has been found to be always acting between two bodies kept close to each other in different media. The properties of the force are different as compared to other non-contact forces such as gravitation and electrostatics, as was shown in our previous work. The aim of this paper is to find how the force behaves when two objects are brought near each other, one being completely immersed in the medium and the other kept just outside. The magnitude of the force in each medium has been calculated through experiments and then compared with each other. The discrepancies obtained between these magnitudes (10-5 N in water and 10-6 N in engine oil) and the varied oscillation patterns (amplitude and frequency) obtained from graphs have shown that the force behaves differently with different media. In general, the frequency of the force has been found to be of the order 10-2 Hz. The behaviour has also been found to depend on the nature of the material and shape of the object. This correlation has been ascertained by using a Gauss meter to measure the force acting between two objects and also that of an individual object. The polarity of the force i.e. whether attractive or repulsive, has been found to vary across the length of the objects and graphs have been plotted to demonstrate this property.

Fast algorithms for evaluating the stress field of dislocation lines in anisotropic elastic media

NASA Astrophysics Data System (ADS)

Chen, C.; Aubry, S.; Oppelstrup, T.; Arsenlis, A.; Darve, E.

2018-06-01

In dislocation dynamics (DD) simulations, the most computationally intensive step is the evaluation of the elastic interaction forces among dislocation ensembles. Because the pair-wise interaction between dislocations is long-range, this force calculation step can be significantly accelerated by the fast multipole method (FMM). We implemented and compared four different methods in isotropic and anisotropic elastic media: one based on the Taylor series expansion (Taylor FMM), one based on the spherical harmonics expansion (Spherical FMM), one kernel-independent method based on the Chebyshev interpolation (Chebyshev FMM), and a new kernel-independent method that we call the Lagrange FMM. The Taylor FMM is an existing method, used in ParaDiS, one of the most popular DD simulation softwares. The Spherical FMM employs a more compact multipole representation than the Taylor FMM does and is thus more efficient. However, both the Taylor FMM and the Spherical FMM are difficult to derive in anisotropic elastic media because the interaction force is complex and has no closed analytical formula. The Chebyshev FMM requires only being able to evaluate the interaction between dislocations and thus can be applied easily in anisotropic elastic media. But it has a relatively large memory footprint, which limits its usage. The Lagrange FMM was designed to be a memory-efficient black-box method. Various numerical experiments are presented to demonstrate the convergence and the scalability of the four methods.

Effect of sequential release of NAPLs on NAPL migration in porous media

NASA Astrophysics Data System (ADS)

Bang, Woohui; Yeo, In Wook

2016-04-01

NAPLs (Non-aqueous phase liquids) are common groundwater contaminants and are classified as LNAPLs (Light non-aqueous phase liquids) and DNAPLs (Dense non-aqueous phase liquids) according to relative density for water. Due to their low solubility in water, NAPLs remain for a long time in groundwater, and they pose a serious environmental problem. Therefore, understanding NAPLs migration in porous media is essential for effective NAPLs remediation. DNAPLs tend to move downward through the water table by gravity force because its density is higher than water. However, if DNAPLs do not have sufficient energy which breaks capillary force of porous media, they will just accumulate above capillary zone or water table. Mobile phase of LNAPLs rises and falls depending on fluctuation of water table, and it could change the wettability of porous media from hydrophilic to hydrophobic. This could impacts on the migration characteristics of subsequently-released DNAPLs. LNAPLs and DNAPLs are sometime disposed at the same place (for example, the Hill air force base, USA). Therefore, this study focuses on the effect of sequential release of NAPLs on NAPLs (in particular, DNAPL) migration in porous media. We have conducted laboratory experiments. Gasoline, which is known to change wettability of porous media from hydrophilic to intermediate, and TCE (Trichloroethylene) were used as LNAPL and DNAPL, respectively. Glass beads with the grain size of 1 mm and 2 mm were prepared for two sets of porous media. Gasoline and TCE was dyed for visualization. First, respective LNAPL and DNAPL of 10 ml were separately released into prepared porous media. For the grain size of 2 mm glass beads, LNAPL became buoyant above the water table, and DNAPL just moved downward through porous media. However, for the experiment with the grain size of 1 mm glass beads, NAPLs behaved very differently. DNAPL did not migrate downward below and just remained above the water table due to capillary pressure of porous media. To study the effect of subsequent release of NAPLs, as soon as LNAPL was released to porous medium with 1 mm of glass beads, being buoyant above water table, water table was lowered, which left residuals along the path of LNAPL. DNAPL was subsequently released. DNAPL was breaking through the water table now, which was opposed to only DNAPL release case. This study indicates that sequential release of NAPLs can leads to different migration characteristics of NAPLs, compared with the release of single phase NAPL into porous media.

76 FR 45280 - Notice of ACHP Quarterly Business Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-28

... of Chairman's Award III. Chairman's Report IV. ACHP Management Issues A. Credentials Committee Report... America's Great Outdoors D. ACHP Legislative Agenda E. Sustainability Task Force F. Web Site Update and Social Media G. Preservation Action Federal Preservation Task Force Report and Recommendations VI...

2D VARIABLY SATURATED FLOWS: PHYSICAL SCALING AND BAYESIAN ESTIMATION

EPA Science Inventory

A novel dimensionless formulation for water flow in two-dimensional variably saturated media is presented. It shows that scaling physical systems requires conservation of the ratio between capillary forces and gravity forces. A direct result of this finding is that for two phys...

Defects formation and wave emitting from defects in excitable media

NASA Astrophysics Data System (ADS)

Ma, Jun; Xu, Ying; Tang, Jun; Wang, Chunni

2016-05-01

Abnormal electrical activities in neuronal system could be associated with some neuronal diseases. Indeed, external forcing can cause breakdown even collapse in nervous system under appropriate condition. The excitable media sometimes could be described by neuronal network with different topologies. The collective behaviors of neurons can show complex spatiotemporal dynamical properties and spatial distribution for electrical activities due to self-organization even from the regulating from central nervous system. Defects in the nervous system can emit continuous waves or pulses, and pacemaker-like source is generated to perturb the normal signal propagation in nervous system. How these defects are developed? In this paper, a network of neurons is designed in two-dimensional square array with nearest-neighbor connection type; the formation mechanism of defects is investigated by detecting the wave propagation induced by external forcing. It is found that defects could be induced under external periodical forcing under the boundary, and then the wave emitted from the defects can keep balance with the waves excited from external forcing.

Shaping Student Activists: Discursive Sensemaking of Activism and Participation Research

ERIC Educational Resources Information Center

Taha, Diane E.; Hastings, Sally O.; Minei, Elizabeth M.

2015-01-01

As social media becomes a more potent force in society, particularly for younger generations, the role in activism has been contested. This qualitative study examines 35 interviews with students regarding their perceptions of the use of social media in social change, their perceptions of activists, and their level of self-identification as an…

Using Social Media to Support the Learning Needs of Future IS Security Professionals

ERIC Educational Resources Information Center

Neville, Karen; Heavin, Ciara

2013-01-01

The emergence of social media has forced educators to think differently about the way learning occurs. Students and practitioners alike are using new technologies to connect with peers/colleagues, share ideas, resources and experiences for extracurricular activities. The social business gaming platform considered in this study leverages the social…

Knowing the Past Affectively: Screen Media and the Evocation of Intergenerational Trauma

ERIC Educational Resources Information Center

Dragojlovic, Ana

2018-01-01

This article explores the relationship between the affective intensities of screen media and its potential to serve as an affective force for the transmission of intergenerational trauma. I explore how watching a documentary portraying historical atrocities that preceded the birth of the documentary's viewers yet affected their lives in profound…

The Mass Media Role in Terrorist Campaigns.

ERIC Educational Resources Information Center

Moore, Tim; Clavier, David E.

Terrorists seek recognition for their cause by using violence to create public fear which will force the government into repressive counter-measures. The mass media play a vital role in this strategy. News reports of terrorism may magnify the climate of fear, thereby augmenting the public's overreaction. Moreover, broadcast of terrorist acts may…

Using Social Media as a Tool for Learning: A Multi-Disciplinary Study

ERIC Educational Resources Information Center

Delello, Julie A.; McWhorter, Rochell R.; Camp, Kerri M.

2015-01-01

In order to explore the rich dynamics of using social media as a tool for learning within higher education classrooms, researchers across three disciplines: education, human resource development (HRD), and marketing, joined forces seeking ways to focus on learning through a retrospective analysis. Three concepts--engagement, community building,…

Analysis of physical activity mass media campaign design.

PubMed

Lankford, Tina; Wallace, Jana; Brown, David; Soares, Jesus; Epping, Jacqueline N; Fridinger, Fred

2014-08-01

Mass media campaigns are a necessary tool for public health practitioners to reach large populations and promote healthy behaviors. Most health scholars have concluded that mass media can significantly influence the health behaviors of populations; however the effects of such campaigns are typically modest and may require significant resources. A recent Community Preventive Services Task Force review on stand-alone mass media campaigns concluded there was insufficient evidence to determine their effectiveness in increasing physical activity, partly due to mixed methods and modest and inconsistent effects on levels of physical activity. A secondary analysis was performed on the campaigns evaluated in the Task Force review to determine use of campaign-building principles, channels, and levels of awareness and their impact on campaign outcomes. Each study was analyzed by 2 reviewers for inclusion of campaign building principles. Campaigns that included 5 or more campaign principles were more likely to be successful in achieving physical activity outcomes. Campaign success is more likely if the campaign building principles (formative research, audience segmentation, message design, channel placement, process evaluation, and theory-based) are used as part of campaign design and planning.

KSC-2014-3054

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Representatives from social media outlets participate in a NASA Social at Vandenberg Air Force Base in California for the launch of NASA's Orbiting Carbon Observatory-2, or OCO-2. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

Imaging of optically diffusive media by use of opto-elastography

NASA Astrophysics Data System (ADS)

Bossy, Emmanuel; Funke, Arik R.; Daoudi, Khalid; Tanter, Mickael; Fink, Mathias; Boccara, Claude

2007-02-01

We present a camera-based optical detection scheme designed to detect the transient motion created by the acoustic radiation force in elastic media. An optically diffusive tissue mimicking phantom was illuminated with coherent laser light, and a high speed camera (2 kHz frame rate) was used to acquire and cross-correlate consecutive speckle patterns. Time-resolved transient decorrelations of the optical speckle were measured as the results of localised motion induced in the medium by the radiation force and subsequent propagating shear waves. As opposed to classical acousto-optic techniques which are sensitive to vibrations induced by compressional waves at ultrasonic frequencies, the proposed technique is sensitive only to the low frequency transient motion induced in the medium by the radiation force. It therefore provides a way to assess both optical and shear mechanical properties.

Force, torque, linear momentum, and angular momentum in classical electr odynamics

NASA Astrophysics Data System (ADS)

Mansuripur, Masud

2017-10-01

The classical theory of electrodynamics is built upon Maxwell's equations and the concepts of electromagnetic (EM) field, force, energy, and momentum, which are intimately tied together by Poynting's theorem and by the Lorentz force law. Whereas Maxwell's equations relate the fields to their material sources, Poynting's theorem governs the flow of EM energy and its exchange between fields and material media, while the Lorentz law regulates the back-and-forth transfer of momentum between the media and the fields. An alternative force law, first proposed by Einstein and Laub, exists that is consistent with Maxwell's equations and complies with the conservation laws as well as with the requirements of special relativity. While the Lorentz law requires the introduction of hidden energy and hidden momentum in situations where an electric field acts on a magnetized medium, the Einstein-Laub (E-L) formulation of EM force and torque does not invoke hidden entities under such circumstances. Moreover, total force/torque exerted by EM fields on any given object turns out to be independent of whether the density of force/torque is evaluated using the law of Lorentz or that of Einstein and Laub. Hidden entities aside, the two formulations differ only in their predicted force and torque distributions inside matter. Such differences in distribution are occasionally measurable, and could serve as a guide in deciding which formulation, if either, corresponds to physical reality.

KSC-2015-1216

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Sam Thurman, deputy project manager for NASA's Soil Moisture Active Passive mission, or SMAP, addresses the audience of a NASA Social held at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

Robophysical study of jumping dynamics on granular media

NASA Astrophysics Data System (ADS)

Aguilar, Jeffrey; Goldman, Daniel I.

2016-03-01

Characterizing forces on deformable objects intruding into sand and soil requires understanding the solid- and fluid-like responses of such substrates and their effect on the state of the object. The most detailed studies of intrusion in dry granular media have revealed that interactions of fixed-shape objects during free impact (for example, cannonballs) and forced slow penetration can be described by hydrostatic- and hydrodynamic-like forces. Here we investigate a new class of granular interactions: rapid intrusions by objects that change shape (self-deform) through passive and active means. Systematic studies of a simple spring-mass robot jumping on dry granular media reveal that jumping performance is explained by an interplay of nonlinear frictional and hydrodynamic drag as well as induced added mass (unaccounted by traditional intrusion models) characterized by a rapidly solidified region of grains accelerated by the foot. A model incorporating these dynamics reveals that added mass degrades the performance of certain self-deformations owing to a shift in optimal timing during push-off. Our systematic robophysical experiment reveals both new soft-matter physics and principles for robotic self-deformation and control, which together provide principles of movement in deformable terrestrial environments.

Effect of ultrasonic stimulation on particle transport and fate over different lengths of porous media

NASA Astrophysics Data System (ADS)

Chen, Xingxin; Wu, Zhonghan; Cai, Qipeng; Cao, Wei

2018-04-01

It is well established that seismic waves traveling through porous media stimulate fluid flow and accelerate particle transport. However, the mechanism remains poorly understood. To quantify the coupling effect of hydrodynamic force, transportation distance, and ultrasonic stimulation on particle transport and fate in porous media, laboratory experiments were conducted using custom-built ultrasonic-controlled soil column equipment. Three column lengths (23 cm, 33 cm, and 43 cm) were selected to examine the influence of transportation distance. Transport experiments were performed with 0 W, 600 W, 1000 W, 1400 W, and 1800 W of applied ultrasound, and flow rates of 0.065 cm/s, 0.130 cm/s, and 0.195 cm/s, to establish the roles of ultrasonic stimulation and hydrodynamic force. The laboratory results suggest that whilst ultrasonic stimulation does inhibit suspended-particle deposition and accelerate deposited-particle release, both hydrodynamic force and transportation distance are the principal controlling factors. The median particle diameter for the peak concentration was approximately 50% of that retained in the soil column. Simulated particle-breakthrough curves using extended traditional filtration theory effectively described the experimental curves, particularly the curves that exhibited a higher tailing concentration.

Media, a President, and His Generals: How the Media Shaped Civil-Military Relations during the Mexican War

DTIC Science & Technology

2011-05-19

Francis Blair worked out of the White House as the newspaper editor of the Washington Globe . This media outlet served to promote Presidential policies...captured his position. After working out an agreement for parole from confinement, Scott defiantly rejoined the fight against the Red Coats. His heroic...General Taylor, “A little more grape , Captain Bragg,” referring to the skill of U.S. artillery fire against the numerically superior Mexican forces

Media and Influence

NASA Astrophysics Data System (ADS)

Bennett, William H.

The public information media provides information on current events (news), entertainment (programming), and opinions offered by trusted public sources (e.g., business, academic or religious spokespersons, journalists, and government officials). Consequently, it is a major force in shaping a populace's attitudes toward significant social issues and of great interest to intervention planners. The chapter attempts to provide modelers and intervention analysts alike with sufficient understanding of media mechanisms and current research that they can begin contributing to, and benefiting from this important area of study.

A Media Mix Test of Paid Radio Advertising for Armed Services Recruitment. Volume II.

DTIC Science & Technology

1976-05-01

This was a test of the effectiveness of paid radio recruiting advertising . The four active military services (Army, Navy, Air Force, Marine Corps...service, awareness and knowledge of specific programs and benefits offered by individual services and awareness of armed forces advertising . (Author)

A Media MIX Test of Paid Radio Advertising for Armed Services Recruitment. Volume 3. Addendum.

DTIC Science & Technology

1976-07-01

This was a test of the effectiveness of paid radio recruiting advertising . The four active military services (Army, Navy, Air Force, Marine Corps...service, awareness and knowledge of specific programs and benefits offered by individual services and awareness of armed forces advertising . (Author)

Common Bibliographic Standards for Baylor University Libraries. Revised.

ERIC Educational Resources Information Center

Scott, Sharon; And Others

Developed by a Baylor University (Texas) Task Force, the revised policies of bibliographic standards for the university libraries provide formats for: (1) archives and manuscript control; (2) audiovisual media; (3) books; (4) machine-readable data files; (5) maps; (6) music scores; (7) serials; and (8) sound recordings. The task force assumptions…

Air Force Reserve Command

Science.gov Websites

Page Get One Now AFR Mission and Vision Statement Social Media Facebook Logo #AlwaysThere Facebook Logo Technician job vacancies on USAJobs.gov 2017 AFR Modernization Book AFR Vision and Guiding Principles 2013 AFR Vision Update 2015 Contact Air Force Reserve AFRC Public Affairs AF Reserve Recruiting Service

32 CFR 865.3 - Application procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (DD Form 149) and http://www.e-publishing.af.mil/shared/media/epubs/AFPAM36-2607.pdf (Air Force...) The name under which the member served. (2) The member's social security number or Air Force service... term “counsel” includes members in good standing of the bar of any state, accredited representatives of...

32 CFR 865.3 - Application procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (DD Form 149) and http://www.e-publishing.af.mil/shared/media/epubs/AFPAM36-2607.pdf (Air Force...) The name under which the member served. (2) The member's social security number or Air Force service... term “counsel” includes members in good standing of the bar of any state, accredited representatives of...

32 CFR 865.3 - Application procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (DD Form 149) and http://www.e-publishing.af.mil/shared/media/epubs/AFPAM36-2607.pdf (Air Force...) The name under which the member served. (2) The member's social security number or Air Force service... term “counsel” includes members in good standing of the bar of any state, accredited representatives of...

32 CFR 865.3 - Application procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (DD Form 149) and http://www.e-publishing.af.mil/shared/media/epubs/AFPAM36-2607.pdf (Air Force...) The name under which the member served. (2) The member's social security number or Air Force service... term “counsel” includes members in good standing of the bar of any state, accredited representatives of...

Velocity Potential in Engineering Hydraulics versus Force Potential in Groundwater Dynamics

NASA Astrophysics Data System (ADS)

Weyer, K.

2013-12-01

Within engineering practice, the calculation of subsurface flow is dominated by the mathematical pseudo-physics of the engineer's adaptation of continuum methods to mechanics. Continuum mechanics rose to prominence in the 19th century in an successful attempt to solve practical engineering problems. To that end were put in place quite a number of simplifications in geometry and the properties of water and other fluids, as well as simplifications of Darcy's equation, in order to find reasonable answers to practical problems by making use of analytical equations. The proof of the correctness of the approach and its usefulness was in the practicability of results obtained. In the 1930s, a diametrically-opposed duality developed in the theoretical derivation of the laws of subsurface fluid flow between Muskat's (1937) velocity potential (engineering hydraulics) and Hubbert's (1940) force potential. The conflict between these authors lasted a lifetime. In the end Hubbert stated on one occasion that Muskat formulates a refined mathematics but does not know what it means in physical terms. In this author's opinion that can still be said about the application of continuum mechanics by engineers to date, as for example to CO2 sequestration, regional groundwater flow, oil sands work, and geothermal studies. To date, engineering hydraulics is best represented by Bear (1972) and de Marsily (1986). In their well-known textbooks, both authors refer to Hubbert's work as the proper way to deal with the physics of compressible fluids. Water is a compressible fluid. The authors then ignore, however, their own insights (de Marsily states so explicitly, Bear does not) and proceed to deal with water as an incompressible fluid. At places both authors assume the pressure gradients to be the main driving force for flow of fluids in the subsurface. That is not, however, the case. Instead the pressure potential forces are caused by compression initiated by unused gravitational energy not required to overcome the resistance to downward flow in penetrated rocks. As one of the consequences, the engineering hydraulics concept of buoyancy forces does not comply with physics. In general the vectorial forces within gravitationally-driven flow systems are ignored when using engineering hydraulics. Scheidegger (1974, p. 79) states, however, verbatim and unequivocally: 'It is thus a force potential and not a velocity potential which governs flow through porous media' (emphasis added). This presentation will outline the proper forces for groundwater flow and their calculations based on Hubbert's force potential and additional physical insights by Weyer (1978). REFERENCES Bear, J. 1972. Dynamics of Fluids in Porous Media. American Elsevier Publishing Company, Inc., New York, NY, USA. de Marsily, G. 1986. Quantitative Hydrogeology: Groundwater Hydrology for Engineers. Academic Press, San Diego, California, USA. Hubbert, M.K. 1940. The theory of groundwater motion. Journal of Geology 48(8): 785-944. Muskat, Morris, 1937. The flow of homogeneous fluids through porous media. McGraw-Hill Book Company Inc., New York, NY, USA Scheidegger. A.E., 1974. The physics of flow through permeable media. Third Edition. University of Toronto Press, Toronto, Ontario, Canada Weyer, K.U., 1978. Hydraulic forces in permeable media. Bulletin du B.R.G.M., Vol. 91, pp. 286-297, Orléans, France.

An Estimate of the Tidal Effects in the Dynamics of the Binary Galaxies

NASA Astrophysics Data System (ADS)

Junqueira, S.; de Freitas Pacheco, J. A.

1990-11-01

RESUMEN. Se ha estimado los efectos de marea en los pares dinamicos de galaxias elipticas. Para poder estudiar tales efectos hernos expandido el potencial gravitacional en potencias del cociente plr hasta en el orden 3 correspondientes a las fuerzas de marea. Hemos examina- do la influencia de este termino en el movimiento orbital. Se encon- tr6 el valor de M/LB = 10+7 (en unidades solares) para un ejemplo de 46 pares E-E usando Ia aproximaci6n de marea. De este resultado, no podemos concluir que existen alrededor de las galaxias halos grandes y obscuros. Hemos encontrado tambien que la suposici6n de masas puntuales es una buena aproximaci6n para el sistema fisico. Sin embargo, tal aproximaci6n sobreestima ligeramente el cociente masa-lurninosidad. ABSTRACT. In the present work we have estimated the tidal effects in the dynamics of pairs of elliptical galaxies. In order to study such effects we have expanded the gravitational potential in power of the ratio p/r up to order 3 corresponding to tidal forces. We examined the influence of this term in the orbital motion. The value of M/LB =lOi7 (in solar units) was found for a sample of 46 E-E pairs using the tidal approximation. From this result, we cannot conclude that large dark haloes exist around galaxies. We have also found that the assump- tion of point masses is a good approximation for the physical system. However, such an approximation overestimates slightly the mass-luminosity ratio. Keq wo't : GALAXIES-DYNAMICS

Media and Democracy: The Emergence of Commercial Broadcasting in the United States, 1927-1935.

ERIC Educational Resources Information Center

McChesney, Robert W.

1992-01-01

Presents U.S. broadcasting history as the interplay between powerful commercial forces and a broadcast reform movement that opposed commercial control of the industry. Suggests that broadcast reformers developed traditions of media criticism that are useful today. Describes the lack of debate preceding the Communications Act of 1934 as a weak spot…

The Games People Play: Information and Media Literacies in the Hunger Games Trilogy

ERIC Educational Resources Information Center

Latham, Don; Hollister, Jonathan M.

2014-01-01

Katniss Everdeen, the narrator and protagonist of Suzanne Collins' Hunger Games Trilogy, survives the grueling ordeal of forced participation in two games to the death through both physical prowess and mental agility. Both within and outside of the Games, she demonstrates information and media literacies. By becoming adept at interpreting and…

Air Education and Training Command > Home

Science.gov Websites

Media Guide (PDF) USAF Social Media Sites Basic Training Technical Training AF Recruiting Service Flying Air Education and Training Command Air Education and Training Command Join the Air Force Home News Our Experts Search Air Education and Training Command: Continuum of Learning AETC Strategic Plan Ask

Complaints and Troubles Talk about the English Language Skills of International Students in Australian Universities

ERIC Educational Resources Information Center

Haugh, Michael

2016-01-01

International students have continued to be the focus of simplistic stereotyping in media discourse where they are frequently identified as one of the forces behind declining academic standards in Australian universities. Their English language skills, in particular, have continued to be the focus of debate both in the mainstream media and in…

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

Jon Morse, director, Astrophysics Division at NASA Headquarters talks about the Kepler mission during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

Military Representation: The Theoretical and Practical Implications of Population Representation in the American Armed Forces

DTIC Science & Technology

1979-10-01

racism " even before the Vietnam casualty statistics received attention in the national news media. In...409 In theory , then, a highly unrepresentative (in statistical terms) force could be an "approximately representative" force. Depending on the balance...of Army representation." The six-month project appeared at the outset to be a well-defined, strictly "objective," statistical evaluation of

Wake Characteristics of a Flapping Wing Optimized for both Aerial and Aquatic Flight

NASA Astrophysics Data System (ADS)

Izraelevitz, Jacob; Kotidis, Miranda; Triantafyllou, Michael

2017-11-01

Multiple aquatic bird species (including murres, puffins, and other auks) employ a single actuator to propel themselves in two different fluid media: both flying and swimming using primarily their flapping wings. This impressive design compromise could be adopted by engineered implementations of dual aerial/aquatic robotic platforms, as it offers an existence proof for favorable flow physics. We discuss one realization of a 3D flapping wing actuation system for use in both air and water. The wing oscillates by the root and employs an active in-line motion degree-of-freedom. An experiment-coupled optimization routine generates the wing trajectories, controlling the unsteady forces throughout each flapping cycle. We elucidate the wakes of these wing trajectories using dye visualization, correlating the wake vortex structures with simultaneous force measurements. After optimization, the wing generates the large force envelope necessary for propulsion in both fluid media, and furthermore, demonstrate improved control over the unsteady wake.

KSC-2015-1221

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Col. Marc Del Rosario, commander of the 30th Space Wing Operations Group, addresses the audience of a NASA Social held for NASA's Soil Moisture Active Passive mission, or SMAP, at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

KSC-2015-1217

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Wendy Edelstein, instrument manager for NASA's Soil Moisture Active Passive mission, or SMAP, discusses the science and engineering of the mission with the audience of a NASA Social held at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

KSC-2015-1205

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Jared Entin, program scientist for NASA's Soil Moisture Active Passive mission, or SMAP, discusses the science and engineering of the mission with the audience of a NASA Social held at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

KSC-2015-1204

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Jared Entin, program scientist for NASA's Soil Moisture Active Passive mission, or SMAP, discusses the science and engineering of the mission with the audience of a NASA Social held at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

A Moral Panic? The Problematization of Forced Marriage in British Newspapers.

PubMed

Anitha, Sundari; Gill, Aisha K

2015-09-01

This article examines the British media's construction of forced marriage (FM) as an urgent social problem in a context where other forms of violence against women are not similarly problematized. A detailed analysis of four British newspapers over a 10-year period demonstrates that media reporting of FM constitutes a moral panic in that it is constructed as a cultural problem that threatens Britain's social order rather than as a specific form of violence against women. Thus, the current problematization of FM restricts discursive spaces for policy debates and hinders attempts to respond to this problem as part of broader efforts to tackle violence against women. © The Author(s) 2015.

USING SOIL AND OTHER PLANT GROWING MEDIA EFFECTIVELY. HORTICULTURE-SERVICE OCCUPATIONS, MODULE NO. 5.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. Center for Vocational and Technical Education.

ONE OF A SERIES DESIGNED TO PREPARE HIGH SCHOOL STUDENTS FOR HORTICULTURE SERVICE OCCUPATIONS, THIS MODULE HAS AS ITS MAJOR OBJECTIVE TO DEVELOP THE APPRECIATIONS, UNDERSTANDINGS, AND ABILITIES NEEDED TO USE PLANT GROWING MEDIA IN GROWING HORTICULTURAL PLANTS. IT WAS DEVELOPED BY A NATIONAL TASK FORCE ON THE BASIS OF DATA FROM STATE STUDIES.…

A Non-Blaming Chance and Action Approach to Therapy with Sexually Explicit Media Overuse: A Case Study

ERIC Educational Resources Information Center

Wernik, Uri

2012-01-01

In this clinical presentation a non-blaming, non-judgmental approach to overuse of sexually explicit media (SEM) is introduced. This approach normalizes the problem and sees it in the context of evolution and market forces. It is claimed that such an approach contributes to change and strengthens the therapeutic alliance. A new technique utilizing…

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

Debra Fischer, a professor of Astronomy at San Francisco State University, talks about the Kepler mission during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

Jim Fanson, Kepler project manager, right, talks about the Kepler mission as William Borucki, left, listens during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

ISIS and Social Media: The Combatant Commander’s Guide to Countering ISIS’s Social Media Campaign

DTIC Science & Technology

2015-06-07

temptation to use mirror imaging, or to try to fit ISIS into a simple, pre-determined ideological box. This is especially important when trying to design...fighters play an important role as willing suicide bombers and they also portray the image that the Islamic State stands as a transnational force of

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Stephanie Smith, Digital & Social Media Supervisor, Jet Propulsion Laboratory moderates a prelaunch media briefing for the NASA InSight mission, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

KSC-2014-3061

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Annmarie Eldering, Orbiting Carbon Observatory-2 deputy project scientist at NASA's Jet Propulsion Laboratory, discusses the observatory, or OCO-2, with representatives of social media outlets attending a NASA Social at Vandenberg Air Force Base in California. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

KSC-2014-3056

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Ralph Basilio, project manager for NASA's Orbiting Carbon Observatory-2 at NASA's Jet Propulsion Laboratory, briefs representatives of social media outlets on the observatory, or OCO-2, at a NASA Social held on Vandenberg Air Force Base in California. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

KSC-2014-3057

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Representatives from social media outlets are provided with a series of briefings on NASA's Orbiting Carbon Observatory-2, or OCO-2, at a NASA Social held on Vandenberg Air Force Base in California. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

KSC-2014-3055

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Ralph Basilio, project manager for NASA's Orbiting Carbon Observatory-2 from NASA's Jet Propulsion Laboratory, discusses the observatory, or OCO-2, with representatives of social media outlets attending a NASA Social at Vandenberg Air Force Base in California. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

KSC-2014-3058

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Ken Jucks, project executive for NASA's Orbiting Carbon Observatory-2 from NASA Headquarters, discusses the observatory, or OCO-2, with representatives of social media outlets attending a NASA Social at Vandenberg Air Force Base in California. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

KSC-2014-3060

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Randy Pollock, project architect for NASA's Orbiting Carbon Observatory-2, or OCO-2, from NASA's Jet Propulsion Laboratory, or JPL, and Pavani Peddada, OCO-2 engineer from JPL, discuss the observatory with representatives of social media outlets attending a NASA Social at Vandenberg Air Force Base in California. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

BACTERIOPHAGE AND MICROSPHERE TRANSPORT IN SATURATED POROUS MEDIA: FORCED-GRADIENT EXPERIMENT AT BORDEN, ONTARIO

EPA Science Inventory

A two-well forced-gradient experiment involving virus and microsphere transport was carried out in a sandy aquifer in Borden, Ontario, Canada. Virus traveled at least a few meters in the experiment, but virus concentrations at observation points 1 and 2.54 m away from the injecti...

U.S. Air Force > About Us > Observances

Science.gov Websites

Media Sites Site Registration Contact Us Search AF.mil: Highlights APIM-Rotator Womens History Month African American History Month posters African American History Month Asian American Pacific Islander . (U.S. Air Force photo by Staff Sgt. Will McCrary/Released). USAFE band member discovers family history

Defense.gov - Special Report: Travels with Lynn

Science.gov Websites

social media. Story Simulation Center Provides Taste of Combat MARINE CORPS BASE CAMP PENDELTON, Calif Force's battle simulation center at Marine Corps Base Camp Pendleton, Calif. Story 'Adaptable' U.S. Troops Visits Vandenberg Air Force Base and Los Angeles Lynn Visits Navy and Marine Bases About This Site DoD

32 CFR Appendix A to Part 631 - Armed Forces Disciplinary Control Board Procedures Guide

Code of Federal Regulations, 2013 CFR

2013-07-01

..., and law enforcement officials. (2) Housing part and enforcement authorities. (3) Health, and social... appropriate by the sponsoring command such as, news media, union representatives, and so forth. b. Invited... detrimental to the good order and discipline, health, morale, welfare, safety, and morals of Armed Forces...

32 CFR Appendix A to Part 631 - Armed Forces Disciplinary Control Board Procedures Guide

Code of Federal Regulations, 2011 CFR

2011-07-01

..., and law enforcement officials. (2) Housing part and enforcement authorities. (3) Health, and social... appropriate by the sponsoring command such as, news media, union representatives, and so forth. b. Invited... detrimental to the good order and discipline, health, morale, welfare, safety, and morals of Armed Forces...

32 CFR Appendix A to Part 631 - Armed Forces Disciplinary Control Board Procedures Guide

Code of Federal Regulations, 2012 CFR

2012-07-01

..., and law enforcement officials. (2) Housing part and enforcement authorities. (3) Health, and social... appropriate by the sponsoring command such as, news media, union representatives, and so forth. b. Invited... detrimental to the good order and discipline, health, morale, welfare, safety, and morals of Armed Forces...

32 CFR Appendix A to Part 631 - Armed Forces Disciplinary Control Board Procedures Guide

Code of Federal Regulations, 2010 CFR

2010-07-01

..., and law enforcement officials. (2) Housing part and enforcement authorities. (3) Health, and social... appropriate by the sponsoring command such as, news media, union representatives, and so forth. b. Invited... detrimental to the good order and discipline, health, morale, welfare, safety, and morals of Armed Forces...

32 CFR Appendix A to Part 631 - Armed Forces Disciplinary Control Board Procedures Guide

Code of Federal Regulations, 2014 CFR

2014-07-01

..., and law enforcement officials. (2) Housing part and enforcement authorities. (3) Health, and social... appropriate by the sponsoring command such as, news media, union representatives, and so forth. b. Invited... detrimental to the good order and discipline, health, morale, welfare, safety, and morals of Armed Forces...

Air Force Public Affairs - Can It Support Air Force Doctrine More Effectively.

DTIC Science & Technology

1987-04-01

government resources to operate, maintain and modernize its forces. * 3 In the early 1980’s movie about the first American astronauts, ’The Right... movie portrayed and also is true now. If you accept the premise that funding is what makes aircraft and missiles fly, then the emphasis is to gain...consists of divisions which are functionally aligned into Media Relations, Community Relations, Internal Information, and Security Review and Plans

XRAYS (eXamining Relevance of Articles to Young Survivors) Program Survey of Information Needs and Media Use by Young Breast Cancer Survivors and Young Women at High-Risk for Breast Cancer.

PubMed

Yi, Robin H Pugh; Rezende, Lisa F; Huynh, Julie; Kramer, Karen; Cranmer, Melissa; Schlager, Lisa; Dearfield, Craig T; Friedman, Susan J

2017-09-28

Women age 45 years or younger with breast cancer, or who are at high-risk for breast cancer due to previously having the disease or to genetic risk, have distinct health risks and needs from their older counterparts. Young women frequently seek health information through the Internet and mainstream media, but often find it does not address their particular concerns, that it is difficult to evaluate or interpret, or even misleading. To help women better understand media coverage about new research, Facing Our Risk of Cancer Empowered (FORCE) developed the CDC-funded XRAYS (eXamining Relevance of Articles to Young Survivors) program. To assure that the XRAYS program is responsive to the community's needs, FORCE launched a web-based survey to assess where young women seek information about breast cancer, and to learn their unmet information needs. A total of 1,178 eligible women responded to the survey. In general, the breast cancer survivors and high-risk women between ages 18-45 years who responded to this survey, are using multiple media sources to seek information about breast cancer risk, prevention, screening, and treatment. They place trust in several media sources and use them to inform their medical decisions. Only about one-third of respondents to this survey report discussing media sources with their health care providers. Current survey results indicate that, by providing credible information on the quality of evidence and reporting in media reports on cancer, XRAYS is addressing a key need for health information. Results suggest that it will be useful for XRAYS to offer reviews of articles on a broad range of topics that can inform decisions at each stage of risk assessment and treatment.

Propulsion via flexible flapping in granular media

NASA Astrophysics Data System (ADS)

Peng, Zhiwei; Ding, Yang; Pietrzyk, Kyle; Elfring, Gwynn J.; Pak, On Shun

2017-07-01

Biological locomotion in nature is often achieved by the interaction between a flexible body and its surrounding medium. The interaction of a flexible body with granular media is less understood compared with viscous fluids partially due to its complex rheological properties. In this work, we explore the effect of flexibility on granular propulsion by considering a simple mechanical model in which a rigid rod is connected to a torsional spring that is under a displacement actuation using a granular resistive force theory. Through a combined numerical and asymptotic investigation, we characterize the propulsive dynamics of such a flexible flapper in relation to the actuation amplitude and spring stiffness, and we compare these dynamics with those observed in a viscous fluid. In addition, we demonstrate that the maximum possible propulsive force can be obtained in the steady propulsion limit with a finite spring stiffness and large actuation amplitude. These results may apply to the development of synthetic locomotive systems that exploit flexibility to move through complex terrestrial media.

Reviewing and addressing the link between mass media and the increase in obesity among European children: The European Academy of Paediatrics (EAP) and The European Childhood Obesity Group (ECOG) consensus statement.

PubMed

Mazur, Artur; Caroli, Margherita; Radziewicz-Winnicki, Igor; Nowicka, Paulina; Weghuber, Daniel; Neubauer, David; Dembiński, Łukasz; Crawley, Francis P; White, Martin; Hadjipanayis, Adamos

2018-04-01

This study reviewed the link between social media and the growing epidemic of childhood obesity in Europe. A task force from the European Academy of Paediatrics and the European Childhood Obesity Group searched published literature and developed a consensus statement. It found that there was evidence of a strong link between obesity levels across European countries and childhood media exposure and that parents and society needed a better understanding of the influence of social media on dietary habits. Health policies in Europe must take account of the range of social media influences that promote the development of childhood obesity. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Social media guest listen as Bruce Banerdt, InSight principal investigator, NASA JPL, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

A Strategic Capability Review of the Georgian Armed Forces

DTIC Science & Technology

2012-12-14

Personnel Carrier AT Anti-Tank ATK Attack BCS Battle Command System BDA Battle Damage Assessment BDE Brigade BLOS Beyond Line of Site BN...and Azerbaijan to Turkey and further to the Europe. Informational Friendly There are several media agencies, both press and television, that can...provide relatively accurate information to the population. There are cases of accusations of government influencing media , by NGOs and journalists

Proceedings of the American Journalism Historians' Association Conference (Salt Lake City, Utah, October 5-7, 1993). Part III: Mass Media Studies.

ERIC Educational Resources Information Center

American Journalism Historians' Association.

The Mass Media section of the proceedings of this conference of journalism historians contains the following 10 papers: "Broadcast News, Cable TV and the Telcos: A Historical Examination of the Rhetorical Forces Affecting the Electronic Distribution of Information to the American Television Public" (John E. Craft and Frances R. Matera);…

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

Jim Fanson, Kepler project manager, at NASA's Jet Propulsion Laboratory in Pasadena, Calif. talks about the Kepler mission during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

William Borucki, principal investigator for Kepler Science at Ames Research Center, Moffett Field, Calif., talks about the Kepler mission during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

Jim Fanson, Kepler project manager, center, talks about the Kepler mission as William Borucki, left, and Debra Fischer, right, listen during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

The Media and the Image of War. Study Guide. Episode #724. America's Defense Monitor, Educational TV for the Classroom.

ERIC Educational Resources Information Center

Rizzo, Claudia

This program examines the series of myths generated by the media about war, peace, and the use of force. This episode explores the emergence of the popular interpretation of violence by "good" citizens who use violence to produce positive results during wartime. The study guide offers questions to use before viewing the video, questions to follow…

Perspectives on the '90s. Outlook Report.

ERIC Educational Resources Information Center

Sadowske, P. Sue, Ed.; Adrian, Judith G., Ed.

This report on forces influencing the future is designed to define the challenges that lie ahead and to help individuals develop plans to meet these challenges. It is based on the work of a team of "environmental scanners" who reviewed media, books, and academic research and discussed current issues with a variety of people to explore forces at…

A Computer Code for Dynamic Stress Analysis of Media-Structure Problems with Nonlinearities (SAMSON). Volume III. User’s Manual.

DTIC Science & Technology

NONLINEAR SYSTEMS, LINEAR SYSTEMS, SUBROUTINES , SOIL MECHANICS, INTERFACES, DYNAMICS, LOADS(FORCES), FORCE(MECHANICS), DAMPING, ACCELERATION, ELASTIC...PROPERTIES, PLASTIC PROPERTIES, CRACKS , REINFORCING MATERIALS , COMPOSITE MATERIALS , FAILURE(MECHANICS), MECHANICAL PROPERTIES, INSTRUCTION MANUALS, DIGITAL COMPUTERS...STRESSES, *COMPUTER PROGRAMS), (*STRUCTURES, STRESSES), (*DATA PROCESSING, STRUCTURAL PROPERTIES), SOILS , STRAIN(MECHANICS), MATHEMATICAL MODELS

KSC-2015-1219

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Dara Entekhabi, science team leader at the Massachusetts Institute of Technology in Cambridge, Massachusetts, and other experts discuss the science and engineering of NASA's Soil Moisture Active Passive mission, or SMAP, with the audience of a NASA Social held at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

KSC-2015-1218

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – Dara Entekhabi, science team leader at the Massachusetts Institute of Technology in Cambridge, Massachusetts, discusses the science and engineering of NASA's Soil Moisture Active Passive mission, or SMAP, with the audience of a NASA Social held at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

Microgravity Investigation of Capillary Driven Imbibition

NASA Astrophysics Data System (ADS)

Dushin, V. R.; Nikitin, V. F.; Smirnov, N. N.; Skryleva, E. I.; Tyurenkova, V. V.

2018-05-01

The goal of the present paper is to investigate the capillary driven filtration in porous media under microgravity conditions. New mathematical model that allows taking into account the blurring of the front due to the instability of the displacement that is developing at the front is proposed. The constants in the mathematical model were selected on the basis of the experimental data on imbibition into unsaturated porous media under microgravity conditions. The flow under the action of a combination of capillary forces and a constant pressure drop or a constant flux is considered. The effect of capillary forces and the type of wettability of the medium on the displacement process is studied. A criterion in which case the capillary effects are insignificant and can be neglected is established.

EL MANEJO DE LA BIODIVERSIDAD EN EL SIGLO XXI

Treesearch

ARIEL E. LUGO

2001-01-01

ser humano está transformando rápidamente el planeta Tierra (Meyer y Turner, 1994; Vitousek et al., 1997a). Su actividad tiene efectos globales que modifican el ambiente terrícola (Tabla I). Estos cambios, que comenzaron con la revolución industrial del siglo XIX, serán más notables en el siglo XXI en lo que se ha denominado la era Homogeocena donde el efecto dominante...

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Col. Michael Hough, Commander 30th Space Wing, Vandenberg Air Force Base, left, and 1st Lieutenant Kristina Williams, weather officer, 30th Space Wing, Vandenberg Air Force Base, discuss NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

Wave Propagation and Dynamic Load Transfer due to Explosive Loading in Heterogenous Granular Media with Microstructure

DTIC Science & Technology

1992-09-30

acknowledge the support of the Air Force Office of Scientific Research , Boiling Air Force Base, Washington D.C. under grant No. F49620-89-C-0091 and Major... applied to the present research program by constructing model granular assemblies of birefringent disks which were dynamically loaded by exploding a...Kirtland Air Force Base, on March 26, 1991. He gave us a seminar dealing with his research on micro- geomechanics , and we i presented and discussed several

The Role of Social Media in Crisis

DTIC Science & Technology

2012-06-01

affected regions to be shared with rescue organizations. • Members of social networking sites , such as Twitter and Facebook, spread messages and pleas...internet sites such as blogs, wikis, fora and community journalism. • The authorities monitored local and network news broadcasts, as well as internet...established a dedicated force to monitor and respond to them. Best Paper Award Paper 007: The Role of Social Media in Crisis Lessons From Past

The Worried Well: Strategies for Installation Commanders

DTIC Science & Technology

2005-01-01

require enlisting law enforcement personnel, members of the armed forces, pharmacists , veterinarians, and civilian volunteers to assist. Insights from...television, radio and print media protested that they may not view themselves as partners. They perceive of their role as the Fourth Estate, and have a...watchdog obligation.”52 In spite of the sometimes adversarial or skeptical Pilch—The Worried Well 26 posture that the media may feel their role

Virtual Social Networking and Interoperability in the Canadian Forces Netcentric Environment

DTIC Science & Technology

2009-07-01

as Facebook and Plaxo. 2.1.4 Media-type based social networks Flickr, YouTube , DeviantArt, Vimeo, etc. are all sites that encourage casual and...with content appreciation and criticism. The proportions and traffic generated by sites like YouTube are undeniable, being covered in the media as...1 Visit http://en.wikipedia.org/wiki/ AdSense for further references and a list of similar, competing services

Social Media Strategies for the United States Armed Forces: An Israeli Case Study

DTIC Science & Technology

2013-05-03

experiences a significant military failure. Discussion: The US military is facing pressure to adapt to a rapidly evolving information environment...Marine Corps, but as I explored the issue, it rapidly became apparent that the institutional structures that both enable and constrain social media use... rapidly changing nature of the information environment itself is causing drastic societal changes, with widespread effects on both individual and

Resonance Phenomena in Goupillaud-type Media

DTIC Science & Technology

2010-10-01

time-harmonic forcing function at one end, with the other end fixed. Analytical stress solutions are derived from a global system of recursion...relationships using z-transform methods, where the determinant of the resulting global system matrix |Am| in the z-space is a palindromic polynomial with real...media (35). The present treatment uses a global matrix method that is attributed to Knopoff (36), rather than the Thomsen-Haskell transfer matrix

Operational Commanders: It’s Time to Take Command...of the Media

DTIC Science & Technology

2003-02-03

media companies should only send experienced military reporters to cover U.S. forces. This policy may even raise the journalistic standards of...2. Security Classification Authority: 3. Declassification/Downgrading Schedule: 4. Distribution/Availability of Report : DISTRIBUTION STATEMENT A...Ausiello, USN 10.Type of Report : FINAL 11. Date of Report : 03 February 2003 12.Page Count: 20 12A Paper Advisor (if any): 13.Supplementary Notation

Maxwell Air Force Base

Science.gov Websites

Social Media Guide (PDF) USAF Social Media Sites 42nd Medical Group 42nd Medical Group Voting Assistance : Open 24 hours a day, seven days a week. - Kelly St. Gate: Open Mon-Fri, 6:00 a.m. - 6 p.m., closed weekends, holidays and AETC down days. - Day St. Gate: Open Mon-Fri, 6:00 a.m. - 2:00 p.m. inbound traffic

KSC-2014-3059

NASA Image and Video Library

2014-06-30

VANDENBERG AIR FORCE BASE, Calif. – Col. Keith Balts, 30th Space Wing commander at Vandenberg Air Force Base in California, and Michael "Mic" Woltman, senior vehicle systems engineer for the Launch Services Program at NASA's Kennedy Space Center in Florida, discuss the upcoming launch of NASA's Orbiting Carbon Observatory-2, or OCO-2, with representatives of social media outlets attending a NASA Social at Vandenberg. Launch of OCO-2 aboard a United Launch Alliance Delta II rocket from Space Launch Complex 2 is scheduled for 5:56 a.m. EDT on July 1. The social media users selected to attend the two-day event on June 30 and July 1 are given the same access as news media in an effort to align their experience with those of traditional media. OCO-2 is NASA’s first mission dedicated to studying atmospheric carbon dioxide, the leading human-produced greenhouse gas driving changes in Earth’s climate. OCO-2 will provide a new tool for understanding the human and natural sources of carbon dioxide emissions and the natural "sinks" that absorb carbon dioxide and help control its buildup. The observatory will measure the global geographic distribution of these sources and sinks and study their changes over time. To learn more about OCO-2, visit http://www.nasa.gov/oco2. Photo credit: NASA/Ben Smegelsky

Casimir effect for perfect electromagnetic conductors (PEMCs): a sum rule for attractive/repulsive forces

NASA Astrophysics Data System (ADS)

Rode, Stefan; Bennett, Robert; Yoshi Buhmann, Stefan

2018-04-01

We discuss the Casimir effect for boundary conditions involving perfect electromagnetic conductors, which interpolate between perfect electric conductors and perfect magnetic conductors. Based on the corresponding reciprocal Green’s tensor we construct the Green’s tensor for two perfectly reflecting plates with magnetoelectric coupling (non-reciprocal media) within the framework of macroscopic quantum electrodynamics. We calculate the Casimir force between two arbitrary perfect electromagnetic conductor plates, resulting in a universal analytic expression that connects the attractive Casimir force with the repulsive Boyer force. We relate the results to a duality symmetry of electromagnetism.

Mechanical and Structural Behavior of Granular Material Packed Beds for Space Life Support System Applications

NASA Technical Reports Server (NTRS)

Malla, Ramesh B.; Anandakumar, Ganesh

2005-01-01

Long-term human mission to space, such as living in International Space Station (ISS), Lunar, and Martian bases, and travel to Mars, must m ake use of Advanced Life Support Systems (ALSS) to generate and recycle critical life supporting elements like oxygen and water. Oxygen Gen eration Assembly (OGA) and Water Processor Assembly (WPA), critical c omponents of ALSS, make use of series of granular material packed beds for generation and recycling of oxygen and water. Several granular m aterials can be used for generation, recycling, processing and recovery of oxygen and water. For example, they may include soft bed media, e.g. ion exchange resins for oxygen generation assembly and hard bed media such as, activated alumina, magchem (Magnesium oxide) and activa ted carbon to remove organic species like ethanol, methanol, and urea from wastewater in Water recovery/processing assembly. These beds are generally packed using a plate-spring mechanism to provide sufficien t compaction to the bed media throughout the course of operation. This paper presents results from an experimental study of a full-scale, 3 8.1 cm (15 inches) long and 3.7 cm (1.44 inches) diameter. activated alumina bed enclosed in a cylinder determining its force-displacement behavior, friction mobilizing force, and axial normal stress distribu tion under various axially applied loads and at different levels of packing. It is observed that force-displacement behavior is non-linear for low compaction level and becomes linear with increase in compaction of the bed media. Axial normal stress distribution along the length of the bed media decreased non-linearly with increase in depth from the loading end of the granular media. This paper also presents experimental results on the amount of particulates generated corresponding to various compaction levels. Particulates generated from each of the tests were measured using standard US sieves. It was found that the p articulates and the overall displacement of the bed media increased with decrease in initial compaction of the bed media. This effect could be attributed to the greater tendency for inter-particle sliding/rub bing due to smaller internal friction angles, as seen from the shear tests, at lesser initial compacted levels. Upon unloading, it was obse rved that there was no change in displacement (especially rebounding) in the bed media. This effect could be attributed to the fact that th e porous activated alumina particles fracture/break upon increase in applied load (during loading phase) and occupy void spaces in between the material grains; thereby leading to settling of the media. The lo ad-displacement curve becomes more linear with increase in initial compaction of the bed media. It is concluded that compaction considerabl y affects the load-displacement behavior of the bed media. A series of tests were also conducted on the packed bed media to determine the f orce required to mobilize the friction between the bed media and the housing cylinder. The results from these tests showed the existence of significant friction between the bed media and the encasing stainles s steel cylinder. Further, it was found that friction effects were more pronounced for media with higher initial compaction. Internal frict ion of the granular media was measured using direct shear apparatus. It was observed that the internal friction increased with increase in initial compaction of the bed media. In this study, a computational m odel (CM) is also developed using finite element software ANSYS to verify experimental results obtained for the distribution of the axial n ormal stress and axial displacement along the length of the full-scal e activated alumina bed media. In the computational model, the granular material is considered to have appropriate failure and frictional c ontact exists between the wall and the granular media. It is observed that the model predicts results closely with the experimental method. The compational results show that the axial normal stress distribution along the length of the activated alumina media decreases non-linea rly from the loading end and is negligible beyond a certain depth. Th is can be attributed to the existence of friction between the walls and the media and that the friction takes up most of the applied load.

Quantifying Loss of Acoustic Communication Space for Right Whales in and around a U.S. National Marine Sanctuary

DTIC Science & Technology

2012-01-01

buscan mejorar el manejo de los efectos acumulativos del ruido sobre especies marinas y sus hábitats. Palabras Clave: área marina protegida, especies...dependientes del sonido para comunicarse están poco entendidos. Buscamos desarrollar métodos para cuantificar los efectos del enmascaramiento de la comu... tiempo ( tiempo pico de alimentación). Utilizamos un conjunto de grabadoras acústicas autónomas, temporales, montadas en el fondo en el Santuario

Joint Chiefs of Staff > Media > Speeches

Science.gov Websites

Facebook on Flickr Joint Chiefs Army Chief of Staff Marine Corps Commandant Chief of Naval Operations Air Force Chief of Staff Chief of National Guard Bureau Biographies Directorates Directorates of Management introduce you to somebody. Right there is the chief of staff of the Air Force. Now, why am I - why am I

Phenomenological model of sintering of oxide nuclear fuel with doping admixtures

NASA Astrophysics Data System (ADS)

Baranov, V. G.; Devyatko, Yu. N.; Tenishev, A. V.; Khomyakov, O. V.

2015-12-01

It is shown that a change in the linear dimension of compacted UO2 in the sintering process is associated with its plastic yielding under the action of the forces of residual stress and capillary forces. From the curves of sintering of a fuel with doping admixtures in various gaseous media, its rate of creep is reduced.

[Media Studies: a diachronic and cross-curricular approach].

PubMed

Tomei, G; Di Giorgio, V; Tomei, F; Sancini, A

2011-01-01

Studies on Media have generated analysis and remarks involving many different disciplines. We have just entered the age of Mass Communication. Each media (papers, radio, movie, TV and web too) wants to interpret reality and offer it to its audience. Each message coming from media is sifted and proposed according to the structural and technical characteristics of the media itself (as M.McLuhan said "the medium is the message"). In time there have been interpretations in favour or against as well, as experts detractors or defenders of media; U Eco called them "apocalyptic" and "integrated". In Medicine there are many different pathologies referable to excessive or incorrect utilization of mass-media: obesity due to high-calorie intake caused by sedentary use of TV, anorexia caused by forced imitation of models created by media, anxiety and sleeping disorders in teen-agers caused by watching TV news. Research are being carried out on mental effort due to incorrect use of screen, similar to the research on VDU operators. Categories gathered from Cognitive Ergonomics are suggested to hypothesize models of correct use of media and maybe the capacity of getting free from the influence of media so that aware audience can have a conscious perspective and not the perception of reality based entirely on the use of any media.

Retrieving quantifiable social media data from human sensor networks for disaster modeling and crisis mapping

NASA Astrophysics Data System (ADS)

Aulov, Oleg

This dissertation presents a novel approach that utilizes quantifiable social media data as a human aware, near real-time observing system, coupled with geophysical predictive models for improved response to disasters and extreme events. It shows that social media data has the potential to significantly improve disaster management beyond informing the public, and emphasizes the importance of different roles that social media can play in management, monitoring, modeling and mitigation of natural and human-caused extreme disasters. In the proposed approach Social Media users are viewed as "human sensors" that are "deployed" in the field, and their posts are considered to be "sensor observations", thus different social media outlets all together form a Human Sensor Network. We utilized the "human sensor" observations, as boundary value forcings, to show improved geophysical model forecasts of extreme disaster events when combined with other scientific data such as satellite observations and sensor measurements. Several recent extreme disasters are presented as use case scenarios. In the case of the Deepwater Horizon oil spill disaster of 2010 that devastated the Gulf of Mexico, the research demonstrates how social media data from Flickr can be used as a boundary forcing condition of GNOME oil spill plume forecast model, and results in an order of magnitude forecast improvement. In the case of Hurricane Sandy NY/NJ landfall impact of 2012, we demonstrate how the model forecasts, when combined with social media data in a single framework, can be used for near real-time forecast validation, damage assessment and disaster management. Owing to inherent uncertainties in the weather forecasts, the NOAA operational surge model only forecasts the worst-case scenario for flooding from any given hurricane. Geolocated and time-stamped Instagram photos and tweets allow near real-time assessment of the surge levels at different locations, which can validate model forecasts, give timely views of the actual levels of surge, as well as provide an upper bound beyond which the surge did not spread. Additionally, we developed AsonMaps---a crisis-mapping tool that combines dynamic model forecast outputs with social media observations and physical measurements to define the regions of event impacts.

Swimming in a granular frictional fluid

NASA Astrophysics Data System (ADS)

Goldman, Daniel

2012-02-01

X-ray imaging reveals that the sandfish lizard swims within granular media (sand) using axial body undulations to propel itself without the use of limbs. To model the locomotion of the sandfish, we previously developed an empirical resistive force theory (RFT), a numerical sandfish model coupled to an experimentally validated Discrete Element Method (DEM) model of the granular medium, and a physical robot model. The models reveal that only grains close to the swimmer are fluidized, and that the thrust and drag forces are dominated by frictional interactions among grains and the intruder. In this talk I will use these models to discuss principles of swimming within these granular ``frictional fluids". The empirical drag force laws are measured as the steady-state forces on a small cylinder oriented at different angles relative to the displacement direction. Unlike in Newtonian fluids, resistive forces are independent of speed. Drag forces resemble those in viscous fluids while the ratio of thrust to drag forces is always larger in the granular media than in viscous fluids. Using the force laws as inputs, the RFT overestimates swimming speed by approximately 20%. The simulation reveals that this is related to the non-instantaneous increase in force during reversals of body segments. Despite the inaccuracy of the steady-state assumption, we use the force laws and a recently developed geometric mechanics theory to predict optimal gaits for a model system that has been well-studied in Newtonian fluids, the three-link swimmer. The combination of the geometric theory and the force laws allows us to generate a kinematic relationship between the swimmer's shape and position velocities and to construct connection vector field and constraint curvature function visualizations of the system dynamics. From these we predict optimal gaits for forward, lateral and rotational motion. Experiment and simulation are in accord with the theoretical prediction, and demonstrate that swimming in sand can be viewed as movement in a localized frictional fluid.

Systems approach used in the Gas Centrifuge Enrichment Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rooks, W.A. Jr.

A requirement exists for effective and efficient transfer of technical knowledge from the design engineering team to the production work force. Performance-Based Training (PBT) is a systematic approach to the design, development, and implementation of technical training. This approach has been successfully used by the US Armed Forces, industry, and other organizations. The advantages of the PBT approach are: cost-effectiveness (lowest life-cycle training cost), learning effectiveness, reduced implementation time, and ease of administration. The PBT process comprises five distinctive and rigorous phases: Analysis of Job Performance, Design of Instructional Strategy, Development of Training Materials and Instructional Media, Validation of Materialsmore » and Media, and Implementation of the Instructional Program. Examples from the Gas Centrifuge Enrichment Plant (GCEP) are used to illustrate the application of PBT.« less

Reconfigurable and non-volatile vertical magnetic logic gates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butler, J., E-mail: jbutl001@ucr.edu; Lee, B.; Shachar, M.

2014-04-28

In this paper, we discuss the concept and prototype fabrication of reconfigurable and non-volatile vertical magnetic logic gates. These gates consist of two input layers and a RESET layer. The RESET layer allows the structure to be used as either an AND or an OR gate, depending on its magnetization state. To prove this concept, the gates were fabricated using a multi-layered patterned magnetic media, in which three magnetic layers are stacked and exchange-decoupled via non-magnetic interlayers. We demonstrate the functionality of these logic gates by conducting atomic force microscopy and magnetic force microscopy (MFM) analysis of the multi-layered patternedmore » magnetic media. The logic gates operation mechanism and fabrication feasibility are both validated by the MFM imaging results.« less

Experimental study of forced convection heat transport in porous media

NASA Astrophysics Data System (ADS)

Pastore, Nicola; Cherubini, Claudia; Rapti, Dimitra; Giasi, Concetta I.

2018-04-01

The present study is aimed at extending this thematic issue through heat transport experiments and their interpretation at laboratory scale. An experimental study to evaluate the dynamics of forced convection heat transfer in a thermally isolated column filled with porous medium has been carried out. The behavior of two porous media with different grain sizes and specific surfaces has been observed. The experimental data have been compared with an analytical solution for one-dimensional heat transport for local nonthermal equilibrium condition. The interpretation of the experimental data shows that the heterogeneity of the porous medium affects heat transport dynamics, causing a channeling effect which has consequences on thermal dispersion phenomena and heat transfer between fluid and solid phases, limiting the capacity to store or dissipate heat in the porous medium.

Controlling Casimir force via coherent driving field

NASA Astrophysics Data System (ADS)

Ahmad, Rashid; Abbas, Muqaddar; Ahmad, Iftikhar; Qamar, Sajid

2016-04-01

A four level atom-field configuration is used to investigate the coherent control of Casimir force between two identical plates made up of chiral atomic media and separated by vacuum of width d. The electromagnetic chirality-induced negative refraction is obtained via atomic coherence. The behavior of Casimir force is investigated using Casimir-Lifshitz formula. It is noticed that Casimir force can be switched from repulsive to attractive and vice versa via coherent control of the driving field. This switching feature provides new possibilities of using the repulsive Casimir force in the development of new emerging technologies, such as, micro-electro-mechanical and nano-electro-mechanical systems, i.e., MEMS and NEMS, respectively.

Air-coupled acoustic radiation force for non-contact generation of broadband mechanical waves in soft media

NASA Astrophysics Data System (ADS)

Ambroziński, Łukasz; Pelivanov, Ivan; Song, Shaozhen; Yoon, Soon Joon; Li, David; Gao, Liang; Shen, Tueng T.; Wang, Ruikang K.; O'Donnell, Matthew

2016-07-01

A non-contact method for efficient, non-invasive excitation of mechanical waves in soft media is proposed, in which we focus an ultrasound (US) signal through air onto the surface of a medium under study. The US wave reflected from the air/medium interface provides radiation force to the medium surface that launches a transient mechanical wave in the transverse (lateral) direction. The type of mechanical wave is determined by boundary conditions. To prove this concept, a home-made 1 MHz piezo-ceramic transducer with a matching layer to air sends a chirped US signal centered at 1 MHz to a 1.6 mm thick gelatin phantom mimicking soft biological tissue. A phase-sensitive (PhS)-optical coherence tomography system is used to track/image the mechanical wave. The reconstructed transient displacement of the mechanical wave in space and time demonstrates highly efficient generation, thus offering great promise for non-contact, non-invasive characterization of soft media, in general, and for elasticity measurements in delicate soft tissues and organs in bio-medicine, in particular.

Air-coupled acoustic radiation force for non-contact generation of broadband mechanical waves in soft media

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ambroziński, Łukasz; AGH University of Science and Technology, Krakow 30059; Pelivanov, Ivan, E-mail: ivanp3@uw.edu

A non-contact method for efficient, non-invasive excitation of mechanical waves in soft media is proposed, in which we focus an ultrasound (US) signal through air onto the surface of a medium under study. The US wave reflected from the air/medium interface provides radiation force to the medium surface that launches a transient mechanical wave in the transverse (lateral) direction. The type of mechanical wave is determined by boundary conditions. To prove this concept, a home-made 1 MHz piezo-ceramic transducer with a matching layer to air sends a chirped US signal centered at 1 MHz to a 1.6 mm thick gelatin phantom mimicking softmore » biological tissue. A phase-sensitive (PhS)-optical coherence tomography system is used to track/image the mechanical wave. The reconstructed transient displacement of the mechanical wave in space and time demonstrates highly efficient generation, thus offering great promise for non-contact, non-invasive characterization of soft media, in general, and for elasticity measurements in delicate soft tissues and organs in bio-medicine, in particular.« less

Propulsion via flexible flapping in granular media

NASA Astrophysics Data System (ADS)

Peng, Zhiwei; Ding, Yang; Pietrzyk, Kyle; Elfring, Gwynn; Pak, On Shun

2017-11-01

Biological locomotion in nature is often achieved by the interaction between a flexible body and its surrounding medium. The interaction of a flexible body with granular media is less understood compared with viscous fluids partially due to its complex rheological properties. In this work, we explore the effect of flexibility on granular propulsion by considering a simple mechanical model in which a rigid rod is connected to a torsional spring that is under a displacement actuation using a granular resistive force theory. Through a combined numerical and asymptotic investigation, we characterize the propulsive dynamics of such a flexible flapper in relation to the actuation amplitude and spring stiffness, and we compare these dynamics with those observed in a viscous fluid. In addition, we demonstrate that the maximum possible propulsive force can be obtained in the steady propulsion limit with a finite spring stiffness and large actuation amplitude. These results may apply to the development of synthetic locomotive systems that exploit flexibility to move through complex terrestrial media. Funding for Z.P. and Y.D. was partially provided by NSFC 394 Grant No. 11672029 and NSAF-NSFC Grant No. U1530401.

The role of evidence-based media advocacy in the promotion of tobacco control policies.

PubMed

Lane, Ch'uyasonqo H; Carter, Marina I

2012-06-01

This article discusses the role of evidence-based media advocacy in the promotion of tobacco control policies. Evidence is a driving force for campaigns seeking to implement a tobacco control policy. An effective campaign is based in evidence that demonstrates why a policy should be implemented, and what the potential benefits are. Media advocacy is the process of disseminating information through the communications media where the aim is to effect action, such as a change of policy, or to alter the public's view of an issue. Discussion focuses on: 1) the importance of, and methods for, collecting and communicating evidence and information to make it clear and usable for legislators, the media, and the public; and 2) the role of earned and paid media in advancing tobacco control issues. The discussion is made within the context of a specific advocacy example; in this case the 2010 campaign to increase the tobacco tax in Mexico.

Electromagnetic induction and radiation-induced abnormality of wave propagation in excitable media

NASA Astrophysics Data System (ADS)

Ma, Jun; Wu, Fuqiang; Hayat, Tasawar; Zhou, Ping; Tang, Jun

2017-11-01

Continuous wave emitting from sinus node of the heart plays an important role in wave propagating among cardiac tissue, while the heart beating can be terminated when the target wave is broken into turbulent states by electromagnetic radiation. In this investigation, local periodical forcing is applied on the media to induce continuous target wave in the improved cardiac model, which the effect of electromagnetic induction is considered by using magnetic flux, then external electromagnetic radiation is imposed on the media. It is found that target wave propagation can be blocked to stand in a local area and the excitability of media is suppressed to approach quiescent but homogeneous state when electromagnetic radiation is imposed on the media. The sampled time series for membrane potentials decrease to quiescent state due to the electromagnetic radiation. It could accounts for the mechanism of abnormality in heart failure exposed to continuous electromagnetic field.

Information Operations in Iraq: The Mufsiddoon versus the U.S. and Coalition Forces

DTIC Science & Technology

2008-04-01

language against him; 2) branding the enemy as mufsidoon committing hirabah; 3) making better use of the media (particularly the local Iraqi media); 4...strategy is branding the terrorists as mufsidoon committing hirabah. Words are critically important and the U.S. can make better use of the Arabic...credibility among the Iraqis; 2) convoluted approval procedures for 10; 3) unintentionally reinforcing AQI’s branding efforts; 4) not understanding

The Media’s Role in Combatting Terrorism

DTIC Science & Technology

1991-04-01

changed after the1972 Munich Olympics Massacre; from then on, the PLO was a force to be reckoned and negotiated with. For better or worse, Yasser Arafat...Coverage During Captivity," Political Communication and Persuation . Vol. 5, No. 4, 1988, p. 244. 12. Uri Ra’anan, Robert L. Pfaltzgraff, Jr., Richard H...Media: Problems, Solutions and Counterproblems." Political Communication and Persuation . Vol. 6, 4 November 1989, pp. 311-339. 12. Dilaura, Arnold E

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

Jim Fanson, Kepler project manager, at NASA's Jet Propulsion Laboratory in Pasadena, Calif. holds a model of the Kepler spacecraft as he talks about the Kepler mission during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

In Search of Hyperlocal News: An Examination of the Organizational, Technological and Economic Forces that Shape 21st Century Approaches to Independent Online Journalism

ERIC Educational Resources Information Center

Horning, Michael

2012-01-01

In recent years, many popular media reports have observed a new phenomenon in news known as hyperlocal online news. While some accounts suggest that hyperlocal is different from community news in that it focuses on news at the neighborhood level or on areas that are often less frequently covered by the mainstream media, little research has…

Visualizing and quantifying the crossover from capillary fingering to viscous fingering in a rough fracture

NASA Astrophysics Data System (ADS)

Chen, Yi-Feng; Fang, Shu; Wu, Dong-Sheng; Hu, Ran

2017-09-01

Immiscible fluid-fluid displacement in permeable media is important in many subsurface processes, including enhanced oil recovery and geological CO2 sequestration. Controlled by capillary and viscous forces, displacement patterns of one fluid displacing another more viscous one exhibit capillary and viscous fingering, and crossover between the two. Although extensive studies investigated viscous and capillary fingering in porous media, a few studies focused on the crossover in rough fractures, and how viscous and capillary forces affect the crossover remains unclear. Using a transparent fracture-visualization system, we studied how the two forces impact the crossover in a horizontal rough fracture. Drainage experiments of water displacing oil were conducted at seven flow rates (capillary number log10Ca ranging from -7.07 to -3.07) and four viscosity ratios (M=1/1000,1/500,1/100 and 1/50). We consistently observed lower invading fluid saturations in the crossover zone. We also proposed a phase diagram for the displacement patterns in a rough fracture that is consistent with similar studies in porous media. Based on real-time imaging and statistical analysis of the invasion morphology, we showed that the competition between capillary and viscous forces is responsible for the saturation reduction in the crossover zone. In this zone, finger propagation toward the outlet (characteristic of viscous fingering) as well as void-filling in the transverse/backward directions (characteristic of capillary fingering), are both suppressed. Therefore, the invading fluid tends to occupy larger apertures with higher characteristic front velocity, promoting void-filling toward the outlet with thinner finger growth and resulting in a larger volume of defending fluid left behind.

Social media guidelines and best practices: recommendations from the Council of Residency Directors Social Media Task Force.

PubMed

Pillow, Malford T; Hopson, Laura; Bond, Michael; Cabrera, Daniel; Patterson, Leigh; Pearson, David; Sule, Harsh; Ankel, Felix; Fernández-Frackelton, Madonna; Hall, Ronald V; Kegg, Jason A; Norris, Donald; Takenaka, Katrin

2014-02-01

Social media has become a staple of everyday life among over one billion people worldwide. A social networking presence has become a hallmark of vibrant and transparent communications. It has quickly become the preferred method of communication and information sharing. It offers the ability for various entities, especially residency programs, to create an attractive internet presence and "brand" the program. Social media, while having significant potential for communication and knowledge transfer, carries with it legal, ethical, personal, and professional risks. Implementation of a social networking presence must be deliberate, transparent, and optimize potential benefits while minimizing risks. This is especially true with residency programs. The power of social media as a communication, education, and recruiting tool is undeniable. Yet the pitfalls of misuse can be disastrous, including violations in patient confidentiality, violations of privacy, and recruiting misconduct. These guidelines were developed to provide emergency medicine residency programs leadership with guidance and best practices in the appropriate use and regulation of social media, but are applicable to all residency programs that wish to establish a social media presence.

Social Media Guidelines and Best Practices: Recommendations from the Council of Residency Directors Social Media Task Force

PubMed Central

Pillow, Malford T.; Hopson, Laura; Bond, Michael; Cabrera, Daniel; Patterson, Leigh; Pearson, David; Sule, Harsh; Ankel, Felix; Fernández-Frackelton, Madonna; Hall, Ronald V.; Kegg, Jason A.; Norris, Donald; Takenaka, Katrin

2014-01-01

Social media has become a staple of everyday life among over one billion people worldwide. A social networking presence has become a hallmark of vibrant and transparent communications. It has quickly become the preferred method of communication and information sharing. It offers the ability for various entities, especially residency programs, to create an attractive internet presence and “brand” the program. Social media, while having significant potential for communication and knowledge transfer, carries with it legal, ethical, personal, and professional risks. Implementation of a social networking presence must be deliberate, transparent, and optimize potential benefits while minimizing risks. This is especially true with residency programs. The power of social media as a communication, education, and recruiting tool is undeniable. Yet the pitfalls of misuse can be disastrous, including violations in patient confidentiality, violations of privacy, and recruiting misconduct. These guidelines were developed to provide emergency medicine residency programs leadership with guidance and best practices in the appropriate use and regulation of social media, but are applicable to all residency programs that wish to establish a social media presence. PMID:24578765

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

1st Lieutenant Kristina Williams, weather officer, 30th Space Wing, Vandenberg Air Force Base, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Col. Michael Hough, Commander 30th Space Wing, Vandenberg Air Force Base, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

Generational Theory: Implications for Recruiting the Millennials

DTIC Science & Technology

2006-03-10

basic forces of influence on an individual considering military service: Parents, technology , the New economy, education, and the media.72 Some of...affect this generation specifically. These five forces are all interconnected. For example, the rise in technology is driving the new economy...Parents are demanding more from education. Both technology and the new economy are requiring students who are better educated. And so on. When looking

Evaluation of DOD Contracts Regarding Combating Trafficking in Persons

DTIC Science & Technology

2010-01-15

involving sexual slavery, human trafficking, and debt bondage attracted media attention and motivated Congressional action. Prior to 2000, instances of...forced into prostitution in bars in South Korea frequented by U.S. military personnel. In 2004, reports chronicled allegations of forced labor and debt ... bondage against U.S. contractors in Iraq, leading to foreign embassy involvement. These incidents were contrary to U.S. Government policy regarding

The American Psychological Association Task Force assessment of violent video games: Science in the service of public interest.

PubMed

Calvert, Sandra L; Appelbaum, Mark; Dodge, Kenneth A; Graham, Sandra; Nagayama Hall, Gordon C; Hamby, Sherry; Fasig-Caldwell, Lauren G; Citkowicz, Martyna; Galloway, Daniel P; Hedges, Larry V

2017-01-01

A task force of experts was convened by the American Psychological Association (APA) to update the knowledge and policy about the impact of violent video game use on potential adverse outcomes. This APA Task Force on Media Violence examined the existing literature, including the meta-analyses in the field, since the last APA report on media violence in 2005. Because the most recent meta-analyses were published in 2010 and reflected work through 2009, the task force conducted a search of the published studies from 2009-2013. These recently published articles were scored and assessed by a systematic evidentiary review, followed by a meta-analysis of the high utility studies, as documented in the evidentiary review. Consistent with the literature that we reviewed, we found that violent video game exposure was associated with: an increased composite aggression score; increased aggressive behavior; increased aggressive cognitions; increased aggressive affect, increased desensitization, and decreased empathy; and increased physiological arousal. The size of the effects was similar to that in prior meta-analyses, suggesting a stable result. Our task force concluded that violent video game use is a risk factor for adverse outcomes, but found insufficient studies to examine any potential link between violent video game use and delinquency or criminal behavior. Our technical report is the basis of this article. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Guidelines for Finite Element Modeling of Acoustic Radiation Force-Induced Shear Wave Propagation in Tissue-Mimicking Media

PubMed Central

Palmeri, Mark L.; Qiang, Bo; Chen, Shigao; Urban, Matthew W.

2017-01-01

Ultrasound shear wave elastography is emerging as an important imaging modality for evaluating tissue material properties. In its practice, some systematic biases have been associated with ultrasound frequencies, focal depths and configuration, transducer types (linear versus curvilinear), along with displacement estimation and shear wave speed estimation algorithms. Added to that, soft tissues are not purely elastic, so shear waves will travel at different speeds depending on their spectral content, which can be modulated by the acoustic radiation force excitation focusing, duration and the frequency-dependent stiffness of the tissue. To understand how these different acquisition and material property parameters may affect measurements of shear wave velocity, simulations of the propagation of shear waves generated by acoustic radiation force excitations in viscoelastic media are a very important tool. This article serves to provide an in-depth description of how these simulations are performed. The general scheme is broken into three components: (1) simulation of the three-dimensional acoustic radiation force push beam, (2) applying that force distribution to a finite element model, and (3) extraction of the motion data for post-processing. All three components will be described in detail and combined to create a simulation platform that is powerful for developing and testing algorithms for academic and industrial researchers involved in making quantitative shear wave-based measurements of tissue material properties. PMID:28026760

Advanced Management Communication: An Elective Course in Corporate Communication.

ERIC Educational Resources Information Center

Argenti, Paul A.

1986-01-01

Proposes a college-level elective course in advanced management communication that would teach future managers how to communicate with shareholders, the media, financial analysts, and the labor force. (SRT)

Primed for death: Law enforcement-citizen homicides, social media, and retaliatory violence.

PubMed

Bejan, Vladimir; Hickman, Matthew; Parkin, William S; Pozo, Veronica F

2018-01-01

We examine whether retaliatory violence exists between law enforcement and citizens while controlling for any social media contagion effect related to prior fatal encounters. Analyzed using a trivariate dynamic structural vector-autoregressive model, daily time-series data over a 21-month period captured the frequencies of police killed in the line of duty, police deadly use of force incidents, and social media coverage. The results support a significant retaliatory violence effect against minorities by police, yet there is no evidence of retaliatory violence against law enforcement officers by minorities. Also, social media coverage of the Black Lives Matter movement increases the risk of fatal victimization to both law enforcement officers and minorities. Possible explanations for these results are based in rational choice and terror management theories.

Primed for death: Law enforcement-citizen homicides, social media, and retaliatory violence

PubMed Central

Bejan, Vladimir; Hickman, Matthew; Pozo, Veronica F.

2018-01-01

We examine whether retaliatory violence exists between law enforcement and citizens while controlling for any social media contagion effect related to prior fatal encounters. Analyzed using a trivariate dynamic structural vector-autoregressive model, daily time-series data over a 21-month period captured the frequencies of police killed in the line of duty, police deadly use of force incidents, and social media coverage. The results support a significant retaliatory violence effect against minorities by police, yet there is no evidence of retaliatory violence against law enforcement officers by minorities. Also, social media coverage of the Black Lives Matter movement increases the risk of fatal victimization to both law enforcement officers and minorities. Possible explanations for these results are based in rational choice and terror management theories. PMID:29320548

Aeroacoustics. [analysis of properties of sound generated by aerodynamic forces

NASA Technical Reports Server (NTRS)

Goldstein, M., E.

1974-01-01

An analysis was conducted to determine the properties of sound generated by aerodynamic forces or motions originating in a flow, such as the unsteady aerodynamic forces on propellers or by turbulent flows around an aircraft. The acoustics of moving media are reviewed and mathematical models are developed. Lighthill's acoustic analogy and the application to turbulent flows are analyzed. The effects of solid boundaries are calculated. Theories based on the solution of linearized vorticity and acoustic field equations are explained. The effects of nonuniform mean flow on the generation of sound are reported.

The Joint Chiefs of Staff Video Collections

Science.gov Websites

Senior Enlisted Advisor Joint Staff History Joint Staff Inspector General Joint Staff Structure Origin of J8 | Force Structure, Resources & Assessment Contact Home : Media : Videos Featured Videos Gen

Distribution and Recovery of Crude Oil in Various Types of Porous Media and Heterogeneity Configurations

NASA Astrophysics Data System (ADS)

Tick, G. R.; Ghosh, J.; Greenberg, R. R.; Akyol, N. H.

2015-12-01

A series of pore-scale experiments were conducted to understand the interfacial processes contributing to the removal of crude oil from various porous media during surfactant-induced remediation. Effects of physical heterogeneity (i.e. media uniformity) and carbonate soil content on oil recovery and distribution were evaluated through pore scale quantification techniques. Additionally, experiments were conducted to evaluate impacts of tetrachloroethene (PCE) content on crude oil distribution and recovery under these same conditions. Synchrotron X-ray microtomography (SXM) was used to obtain high-resolution images of the two-fluid-phase oil/water system, and quantify temporal changes in oil blob distribution, blob morphology, and blob surface area before and after sequential surfactant flooding events. The reduction of interfacial tension in conjunction with the sufficient increase in viscous forces as a result of surfactant flushing was likely responsible for mobilization and recovery of lighter fractions of crude oil. Corresponding increases in viscous forces were insufficient to initiate and maintain the displacement of the heavy crude oil in more homogeneous porous media systems during surfactant flushing. Interestingly, higher relative recoveries of heavy oil fractions were observed within more heterogeneous porous media indicating that wettability may be responsible for controlling mobilization in these systems. Compared to the "pure" crude oil experiments, preliminary results show that crude oil with PCE produced variability in oil distribution and recovery before and after each surfactant-flooding event. Such effects were likely influenced by viscosity and interfacial tension modifications associated with the crude-oil/solvent mixed systems.

Countering Strategic Preclusion: The Requirement for Truly Global Reach in the 21st Century

DTIC Science & Technology

2012-06-01

Website, http://www.618tacc. amc.af.mil/shared/ media /document/AFD-110602-022.pdf (accessed 24 May 2012). The inter-theater airlift support to Operation...Crisis,” Pacific Air Forces Official Website, http://www.pacaf. af.mil/shared/ media /document/AFD-110330-077.pdf [accessed 24 May 2012...Reconnaissance Office (NRO), which lists as one of its key functions providing targeting and BDA support to military operations. These are

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

William Borucki, principal investigator for Kepler Science at Ames Research Center, Moffett Field, Calif., second from left, is seen through a television camer monitor as he talks about the Kepler mission during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

Via Dialogue or Messaging: How Air Force Public Affairs Is Leveraging Social Media

DTIC Science & Technology

2010-12-01

or “blogs”; (2) content-sharing sites (e.g., YouTube, Flickr, Wikis); (3) Micro-blogs (Twitter, Google Buzz); and (4) Social networking sites (e.g...aforementioned categories of social media (blogs, content sharing, micro-blogs, social networking sites , and the optional “other”) are to the overall PA...The results indicate that social networking sites (e.g., Facebook, LinkedIn) were clearly the most utilized by respondents, in terms of posting and

Media interventions to promote responsible sexual behavior.

PubMed

Keller, Sarah N; Brown, Jane D

2002-02-01

While the media have been used effectively to promote sexual responsibility in other countries for decades, few such opportunities have been seized in the United States. Mass media may be especially useful for teaching young people about reproductive health because elements of popular culture can be used to articulate messages in young people s terms, in language that won t embarrass them and may even make safe sex more attractive. Media can potentially change the way people think about sex, amidst cultural pressures to have sex at a young age, to have sex forcefully, or to have unsafe sex. Information can be communicated through a variety of channels--small media (e.g., pamphlets, brochures, and the Internet) and mass media--and in a variety of formats--campaigns, news coverage, and educational messages inserted into regular entertainment programming. Several international studies show that exposure to family planning messages through television, radio, and print media are strongly associated with contraceptive use. Domestically, safe sex media campaigns have been associated with increased teen condom use with casual partners, and reductions in the numbers of teenagers reporting sexual activity. Due to private ownership and First Amendment concerns, U.S. sexual health advocates have been working with the commercial media to incorporate subtle health messages into existing entertainment programming.

Estimation of prenatal aorta intima-media thickness in ultrasound examination

NASA Astrophysics Data System (ADS)

Veronese, Elisa; Poletti, Enea; Cosmi, Erich; Grisan, Enrico

2012-03-01

Prenatal events such as intrauterine growth restriction have been shown to be associated with an increased thickness of abdominal aorta in the fetus. Therefore the measurement of abdominal aortic intima-media thickness (aIMT) has been recently considered a sensitive marker of artherosclerosis risk. To date measure of aortic diameter and of aIMT has been performed manually on US fetal images, thus being susceptible to intra- and inter- operator variability. This work introduces an automatic algorithm that identifies abdominal aorta and estimates its diameter and aIMT from videos recorded during routine third trimester ultrasonographic fetal biometry. Firstly, in each frame, the algorithm locates and segments the region corresponding to aorta by means of an active contour driven by two different external forces: a static vector field convolution force and a dynamic pressure force. Then, in each frame, the mean diameter of the vessel is computed, to reconstruct the cardiac cycle: in fact, we expect the diameter to have a sinusoidal trend, according to the heart rate. From the obtained sinusoid, we identify the frames corresponding to the end diastole and to the end systole. Finally, in these frames we assess the aIMT. According to its definition, we consider as aIMT the distance between the leading edge of the blood-intima interface, and the leading edge of the media-adventitia interface on the far wall of the vessel. The correlation between end-diastole and end-systole aIMT automatic and manual measures is 0.90 and 0.84 respectively.

Developing Air Force Strategic Leadership - A Career Long Process

DTIC Science & Technology

2012-05-14

experience, the Air Force as an organization is more prone to parochialism, myopia and monistic thinking. 27 Besides providing a historical record of... myopia and monistic thinking.” 120 Worden also claims the uniformity of perspective hindered strategic leaders from understanding or recognizing the...discussions in a virtual setting. While the use of social media is a developing concept, some officers have enjoyed early opportunities for PME or

Look and Feel: Haptic Interaction for Biomedicine

DTIC Science & Technology

1995-10-01

algorithm that is evaluated within the topology of the model. During each time step, forces are summed for each mobile atom based on external forces...volumetric properties; (b) conserving computation power by rendering media local to the interaction point; and (c) evaluating the simulation within...alteration of the model topology. Simulation of the DSM state is accomplished by a multi-step algorithm that is evaluated within the topology of the

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

1st Lieutenant Kristina Williams, weather officer, 30th Space Wing, Vandenberg Air Force Base, right, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

US Air Force 1989 Research Initiation Program. Volume 2.

DTIC Science & Technology

1992-06-25

University of Minnesota-Duluth Specialtv: Inorganic Chemistry Specialty: Mechanics Dr. Satish Chandra Mr. Asad Yousuf Kansas State University Savannah...the Study Van der Waals forces in capillary tubes have previously been calculated by Philip (1977b]. His study was based on the Hamaker theory, which...important in condensed media, are not taken into account by the Hamaker theory. Calculations using on the Hamaker theory are often based on an unrealistic

One Health in social networks and social media.

PubMed

Mekaru, S R; Brownstein, J S

2014-08-01

In the rapidly evolving world of social media, social networks, mobile applications and citizen science, online communities can develop organically and separately from larger or more established organisations. The One Health online community is experiencing expansion from both the bottom up and the top down. In this paper, the authors review social media's strengths and weaknesses, earlier work examining Internet resources for One Health, the current state of One Health in social media (e.g. Facebook, Twitter, YouTube) and online social networking sites (e.g. LinkedIn and ResearchGate), as well as social media in One Health-related citizen science projects. While One Health has a fairly strong presence on websites, its social media presence is more limited and has an uneven geographic distribution. In work following the Stone Mountain Meeting,the One Health Global Network Task Force Report recommended the creation of an online community of practice. Professional social networks as well as the strategic use of social media should be employed in this effort. Finally, One Health-related research projects using volunteers (citizen science) often use social media to enhance their recruitment. Including these researchers in a community of practitioners would take full advantage of their existing social media presence. In conclusion, the interactive nature of social media, combined with increasing global Internet access, provides the One Health community with opportunities to meaningfully expand their community and promote their message.

Forced disappearance in an era of globalization: biopolitics, shadow networks, and imagined worlds.

PubMed

Rozema, Ralph

2011-01-01

In this article, I argue that the practice of forced disappearance of persons on the part of paramilitary groups has become linked to specific processes of globalization. Global flows related to biopolitics, global crime networks, and dehumanizing imaginations reproduced by mass media together constitute a driving force behind forced disappearances. Drawing on ethnographic fieldwork in the Colombian city of Medellín, I analyze how these global flows interact with local armed actors, helping create a climate conducive to forced disappearance. These mechanisms in Colombia show similarities to those in some African and Asian countries. Gaining insight into the mechanisms behind forced disappearance may help prevent it from occurring in the future. Enhancing social inclusion of residents, unraveling the transnational crime networks in which perpetrators are involved, and disseminating rehumanizing images of victims all contribute to curbing the practice of forced disappearance.

U.S. Pacific Command > Media > News

Science.gov Websites

Royal Malaysian Navy Enhance Maritime Partnerships in the Region May 24, 2018 - KOTA KINABALU, Malaysia participated in bilateral staff talks with their Royal Malaysian Navy (RMN)... MORE The Future of Land Forces

Solitons shedding from Airy beams and bound states of breathing Airy solitons in nonlocal nonlinear media

PubMed Central

Shen, Ming; Gao, Jinsong; Ge, Lijuan

2015-01-01

We investigate the spatially optical solitons shedding from Airy beams and anomalous interactions of Airy beams in nonlocal nonlinear media by means of direct numerical simulations. Numerical results show that nonlocality has profound effects on the propagation dynamics of the solitons shedding from the Airy beam. It is also shown that the strong nonlocality can support periodic intensity distribution of Airy beams with opposite bending directions. Nonlocality also provides a long-range attractive force between Airy beams, leading to the formation of stable bound states of both in-phase and out-of-phase breathing Airy solitons which always repel in local media. PMID:25900878

Orbital ATK CRS-7 Post Launch News Conference

NASA Image and Video Library

2017-04-18

Members of the news media attend a press conference at NASA's Kennedy Space Center in Florida, after the launch of the Orbital ATK Cygnus pressurized cargo module atop a United Launch Alliance Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station. It was Orbital ATK's seventh commercial resupply services mission to the International Space Station. Liftoff was at 11:11 a.m. EDT. Speaking to the media is Vern Thorp, program manager, commercial missions, United Launch Alliance.

Orbital ATK CRS-7 Post Launch News Conference

NASA Image and Video Library

2017-04-18

Members of the news media attend a press conference at NASA's Kennedy Space Center in Florida, after the launch of the Orbital ATK Cygnus pressurized cargo module atop a United Launch Alliance Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station. It was Orbital ATK's seventh commercial resupply services mission to the International Space Station. Liftoff was at 11:11 a.m. EDT. Speaking to the media is Frank Culbertson, president, Orbital ATK Space Systems Group.

Regular Wave Propagation Out of Noise in Chemical Active Media

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alonso, S.; Sendina-Nadal, I.; Perez-Munuzuri, V.

2001-08-13

A pacemaker, regularly emitting chemical waves, is created out of noise when an excitable photosensitive Belousov-Zhabotinsky medium, strictly unable to autonomously initiate autowaves, is forced with a spatiotemporal patterned random illumination. These experimental observations are also reproduced numerically by using a set of reaction-diffusion equations for an activator-inhibitor model, and further analytically interpreted in terms of genuine coupling effects arising from parametric fluctuations. Within the same framework we also address situations of noise-sustained propagation in subexcitable media.

Off-label use of intravascular iodinated organic and MR contrast media.

PubMed

Tamburrini, O; Aprile, I; Falcone, C; Console, D; Rotundo, A; Rotondo, A

2011-02-01

This paper analyses off-label prescribing of the iodinated organic and magnetic resonance (MR) contrast media used in diagnostic imaging and evaluates the liability profiles and medicolegal issues associated with such use. The term off-label generally indicates the use of known drugs for which new scientific evidence suggests use in a manner and in clinical scenarios not explicitly addressed by the drug data sheet and is outside the indications for which the medication was approved. In addition, the term also indicates the use of drugs with a different route of administration and dosage from those indicated in the information leaflet. Intravascular contrast media used in diagnostic imaging are drugs in the complete sense of the term, even though they have unique characteristics which in many ways distinguish them from other pharmacological agents. The off-label use of contrast media in diagnostic imaging is a little-investigated field and most commonly, but not exclusively, applies to gadolinium-based contrast media used in MR angiography as well as cardiac and paediatric applications. In particular, the off-label use of contrast media mostly concerns deviations from the recommended dose. As contrast media are to all effects pharmaceutical agents, their off-label use can be considered admissible within the limitations laid down by the Italian law in force (Article 3 of Law 94/98) and its interpretation, i.e. the following criteria must be present: the lack of a valid diagnostic alternative; written informed consent by the patient; the presence of scientific publications validated at the international level; assumption of responsibility by the radiologist. The use of contrast media in modern image-guided medicine is essential. In cases in which the information contained in the information leaflet is modified and updated in any way whatsoever (indications, dosage, at others), specifically if restrictions are introduced in accordance with the law in force, the pharmaceutical industry must provide formal and timely notification to radiologists. On their part as prescribers and users of contrast media, radiologists must remain up to date regarding any changes in indications, dosage and route of administration. Lastly, we propose that the radiology report includes not only the type but also the dose of contrast medium used.

KSC-2014-2076

NASA Image and Video Library

2014-04-14

CAPE CANAVERAL, Fla. - Social media representatives photograph the SpaceX Falcon 9 rocket and Dragon Capsule on Space Launch Complex 40 on Cape Canaveral Air Force Station in Florida. NASA Social participants are given the same access as news media in an effort to align the experience of social media representatives with those of traditional media, including the opportunity to view a launch of SpaceX’s Falcon 9 rocket, tour NASA facilities at Kennedy Space Center, speak with representatives from both NASA and SpaceX, view and take photographs of the SpaceX launch pad, meet fellow space enthusiasts who are active on social media and meet members of SpaceX and NASA's social media teams. Scheduled for launch at about 4:58 p.m. EDT April 14, Dragon will be making its fourth trip to the space station. The SpaceX-3 mission, carrying almost 2.5 tons of supplies, technology and science experiments, is the third of 12 flights under NASA's Commercial Resupply Services contract to resupply the orbiting laboratory. For more information, visit http://www.nasa.gov/mission_pages/station/structure/launch/index.html Photo credit: NASA/Glenn Benson

KSC-2014-2074

NASA Image and Video Library

2014-04-14

CAPE CANAVERAL, Fla. - Social media representatives photograph the SpaceX Falcon 9 rocket and Dragon Capsule on Space Launch Complex 40 on Cape Canaveral Air Force Station in Florida. NASA Social participants are given the same access as news media in an effort to align the experience of social media representatives with those of traditional media, including the opportunity to view a launch of SpaceX’s Falcon 9 rocket, tour NASA facilities at Kennedy Space Center, speak with representatives from both NASA and SpaceX, view and take photographs of the SpaceX launch pad, meet fellow space enthusiasts who are active on social media and meet members of SpaceX and NASA's social media teams. Scheduled for launch at about 4:58 p.m. EDT April 14, Dragon will be making its fourth trip to the space station. The SpaceX-3 mission, carrying almost 2.5 tons of supplies, technology and science experiments, is the third of 12 flights under NASA's Commercial Resupply Services contract to resupply the orbiting laboratory. For more information, visit http://www.nasa.gov/mission_pages/station/structure/launch/index.html Photo credit: NASA/Glenn Benson

KSC-2014-2073

NASA Image and Video Library

2014-04-14

CAPE CANAVERAL, Fla. - Social media representatives photograph the SpaceX Falcon 9 rocket and Dragon Capsule on Space Launch Complex 40 on Cape Canaveral Air Force Station in Florida. NASA Social participants are given the same access as news media in an effort to align the experience of social media representatives with those of traditional media, including the opportunity to view a launch of SpaceX’s Falcon 9 rocket, tour NASA facilities at Kennedy Space Center, speak with representatives from both NASA and SpaceX, view and take photographs of the SpaceX launch pad, meet fellow space enthusiasts who are active on social media and meet members of SpaceX and NASA's social media teams. Scheduled for launch at about 4:58 p.m. EDT April 14, Dragon will be making its fourth trip to the space station. The SpaceX-3 mission, carrying almost 2.5 tons of supplies, technology and science experiments, is the third of 12 flights under NASA's Commercial Resupply Services contract to resupply the orbiting laboratory. For more information, visit http://www.nasa.gov/mission_pages/station/structure/launch/index.html Photo credit: NASA/Glenn Benson

Increased iron supplied through Fet3p results in replicative life span extension of Saccharomyces cerevisiae under conditions requiring respiratory metabolism.

PubMed

Botta, Gabriela; Turn, Christina S; Quintyne, Nicholas J; Kirchman, Paul A

2011-10-01

We have previously shown that copper supplementation extends the replicative life span of Saccharomyces cerevisiae when grown under conditions forcing cells to respire. We now show that copper's effect on life span is through Fet3p, a copper containing enzyme responsible for high affinity transport of iron into yeast cells. Life span extensions can also be obtained by supplementing the growth medium with 1mM ferric chloride. Extension by high iron levels is still dependent on the presence of Fet3p. Life span extension by iron or copper requires growth on media containing glycerol as the sole carbon source, which forces yeast to respire. Yeast grown on glucose containing media supplemented with iron show no extension of life span. The iron associated with cells grown in media supplemented with copper or iron is 1.4-1.8 times that of cells grown without copper or iron supplementation. As with copper supplementation, iron supplementation partially rescues the life span of superoxide dismutase mutants. Cells grown with copper supplementation display decreased production of superoxide as measured by dihydroethidium staining. Copyright © 2011 Elsevier Inc. All rights reserved.

Characterization of undulatory locomotion in granular media

NASA Astrophysics Data System (ADS)

Peng, Zhiwei; Pak, On Shun; Elfring, Gwynn

2015-11-01

Undulatory locomotion is ubiquitous in nature, from the swimming of flagellated microorganisms in biological fluids, to the slithering of snakes on land, or the locomotion of sandfish lizards in sand. Analysis of locomotion in granular materials is relatively less developed compared with fluids partially due to a lack of validated force models but a recently proposed resistive force theory (RFT) in granular media has been shown useful in studying the locomotion of a sand-swimming lizard. Here we employ this model to investigate the swimming characteristics of an undulating slender filament of both finite and infinite length. For infinite swimmers, similar to results in viscous fluids, the sawtooth waveform is found to be optimal for propulsion speed at a given power consumption. We also compare the swimming characteristics of sinusoidal and sawtooth swimmers with swimming in viscous fluids. More complex swimming dynamics emerge when the assumption of an infinite swimmer is removed. In particular, we characterize the effects of drifting and pitching in terms of propulsion speed and efficiency for a finite sinusoidal swimmer. The results complement our understanding of undulatory locomotion and provide insights into the effective design of locomotive systems in granular media.

Narrating sexual identities in Kenya: "Choice," value, and visibility.

PubMed

Zingsheim, Jason; Goltz, Dustin Bradley; Murphy, Alexandra G; Mastin, Teresa

2017-04-03

This article examines the discursive construction of female same-sex sexual identities in Nairobi. We identify the discursive forces of "choice," devaluation, and invisibility as influential within Kenyan media representations of lesbian, gay, bisexual, transgender, and intersex citizens. Using creative focus groups and participant observation, we demonstrate how same-sex attracted women in Nairobi resist and rearticulate these discursive forces to assert their identity and agency as individuals and as a queer community.

Numerical simulation on ferrofluid flow in fractured porous media based on discrete-fracture model

NASA Astrophysics Data System (ADS)

Huang, Tao; Yao, Jun; Huang, Zhaoqin; Yin, Xiaolong; Xie, Haojun; Zhang, Jianguang

2017-06-01

Water flooding is an efficient approach to maintain reservoir pressure and has been widely used to enhance oil recovery. However, preferential water pathways such as fractures can significantly decrease the sweep efficiency. Therefore, the utilization ratio of injected water is seriously affected. How to develop new flooding technology to further improve the oil recovery in this situation is a pressing problem. For the past few years, controllable ferrofluid has caused the extensive concern in oil industry as a new functional material. In the presence of a gradient in the magnetic field strength, a magnetic body force is produced on the ferrofluid so that the attractive magnetic forces allow the ferrofluid to be manipulated to flow in any desired direction through the control of the external magnetic field. In view of these properties, the potential application of using the ferrofluid as a new kind of displacing fluid for flooding in fractured porous media is been studied in this paper for the first time. Considering the physical process of the mobilization of ferrofluid through porous media by arrangement of strong external magnetic fields, the magnetic body force was introduced into the Darcy equation and deals with fractures based on the discrete-fracture model. The fully implicit finite volume method is used to solve mathematical model and the validity and accuracy of numerical simulation, which is demonstrated through an experiment with ferrofluid flowing in a single fractured oil-saturated sand in a 2-D horizontal cell. At last, the water flooding and ferrofluid flooding in a complex fractured porous media have been studied. The results showed that the ferrofluid can be manipulated to flow in desired direction through control of the external magnetic field, so that using ferrofluid for flooding can raise the scope of the whole displacement. As a consequence, the oil recovery has been greatly improved in comparison to water flooding. Thus, the ferrofluid flooding is a large potential method for enhanced oil recovery in the future.

Elasticity-induced force reversal between active spinning particles in dense passive media

PubMed Central

Aragones, J. L.; Steimel, J. P.; Alexander-Katz, A.

2016-01-01

The self-organization of active particles is governed by their dynamic effective interactions. Such interactions are controlled by the medium in which such active agents reside. Here we study the interactions between active agents in a dense non-active medium. Our system consists of actuated, spinning, active particles embedded in a dense monolayer of passive, or non-active, particles. We demonstrate that the presence of the passive monolayer alters markedly the properties of the system and results in a reversal of the forces between active spinning particles from repulsive to attractive. The origin of such reversal is due to the coupling between the active stresses and elasticity of the system. This discovery provides a mechanism for the interaction between active agents in complex and structured media, opening up opportunities to tune the interaction range and directionality via the mechanical properties of the medium. PMID:27112961

One Health in social networks and social media

PubMed Central

Mekaru, S.R.; Brownstein, J.S.

2015-01-01

Summary In the rapidly evolving world of social media, social networks, mobile applications and citizen science, online communities can develop organically and separately from larger or more established organisations. The One Health online community is experiencing expansion from both the bottom up and the top down. In this paper, the authors review social media’s strengths and weaknesses, earlier work examining Internet resources for One Health, the current state of One Health in social media (e.g. Facebook, Twitter, YouTube) and online social networking sites (e.g. LinkedIn and ResearchGate), as well as social media in One Health-related citizen science projects. While One Health has a fairly strong presence on websites, its social media presence is more limited and has an uneven geographic distribution. In work following the Stone Mountain Meeting, the One Health Global Network Task Force Report recommended the creation of an online community of practice. Professional social networks as well as the strategic use of social media should be employed in this effort. Finally, One Health-related research projects using volunteers (citizen science) often use social media to enhance their recruitment. Including these researchers in a community of practitioners would take full advantage of their existing social media presence. In conclusion, the interactive nature of social media, combined with increasing global Internet access, provides the One Health community with opportunities to meaningfully expand their community and promote their message. PMID:25707189

Transport of colloids in unsaturated porous media: A pore-scale observation of processes during the dissolution of air-water interface

NASA Astrophysics Data System (ADS)

Sirivithayapakorn, Sanya; Keller, Arturo

2003-12-01

We present results from pore-scale observations of colloid transport in an unsaturated physical micromodel. The experiments were conducted separately using three different sizes of carboxylate polystyrene latex spheres and Bacteriophage MS2 virus. The main focus was to investigate the pore-scale transport processes of colloids as they interact with the air-water interface (AWI) of trapped air bubbles in unsaturated porous media, as well as the release of colloids during imbibition. The colloids travel through the water phase but are attracted to the AWI by either collision or attractive forces and are accumulated at the AWI almost irreversibly, until the dissolution of the air bubble reduces or eliminates the AWI. Once the air bubbles are near the end of the dissolution process, the colloids can be transported by advective liquid flow, as colloidal clusters. The clusters can then attach to other AWI down-gradient or be trapped in pore throats that would have allowed them to pass through individually. We also observed small air bubbles with attached colloids that traveled through the porous medium during the gas dissolution process. We used Derjaguin-Landau-Verwey-Overbeek (DLVO) theory to help explain the observed results. The strength of the force that holds the colloids at the AWI was estimated, assuming that the capillary force is the major force that holds the colloids at the AWI. Our calculations indicate that the forces that hold the colloids at the AWI are larger than the energy barrier between the colloids. Therefore it is quite likely that the clusters of colloids are formed by the colloids attached at the AWI as they move closer at the end of the bubble dissolution process. Coagulation at the AWI may increase the overall filtration for colloids transported through the vadose zone. Just as important, colloids trapped in the AWI might be quite mobile when the air bubbles are released at the end of the dissolution process, resulting in increased breakthrough. These pore-scale mechanisms are likely to play a significant role in the macroscopic transport of colloids in unsaturated porous media.

Superhydrophobic Cones for Continuous Collection and Directional Transportation of CO2 Microbubbles in CO2 Supersaturated Solutions.

PubMed

Xue, Xiuzhan; Yu, Cunming; Wang, Jingming; Jiang, Lei

2016-12-27

Microbubbles are tiny bubbles with diameters below 50 μm. Because of their minute buoyant force, the microbubbles stagnate in aqueous media for a long time, and they sometimes cause serious damage. Most traditional methods chosen for elimination of gas bubbles utilize buoyancy forces including chemical methods and physical methods, and they only have a minor effect on microbubbles. Several approaches have been developed to collect and transport microbubbles in aqueous media. However, the realization of innovative strategies to directly collect and transport microbubbles in aqueous media remains a big challenge. In nature, both spider silk and cactus spines take advantage of their conical-shaped surface to yield the gradient of Laplace pressure and surface free energy for collecting fog droplets from the environment. Inspired by this, we introduce here the gradient of Laplace pressure and surface free energy to the interface of superhydrophobic copper cones (SCCs), which can continuously collect and directionally transport CO 2 microbubbles (from tip side to base side) in CO 2 -supersaturated solution. A gas layer was formed when the microbubbles encounter the SCCs. This offers a channel for microbubble directional transportation. The efficiency of microbubble transport is significantly affected by the apex angle of SCCs and the carbon dioxide concentration. The former provides different gradients of Laplace pressure as the driving force. The latter represents the capacity, which offers the quantity of CO 2 microbubbles for collection and transportation. We believe that this approach provides a simple and valid way to remove microbubbles.

Governing equations for 1D opto-mechanical vibrations of elastic cubical micro-resonators

NASA Astrophysics Data System (ADS)

Sobhani, Hassan; Zohrabi, Mehdi

2018-03-01

In this paper by employing the Lagrangian method, the effect of the radiation pressure on the coupling between the optical and mechanical modes in an elastic cavity is surveyed. The radiation pressure couldn't be considered as an external force because the electromagnetic waves are non-separable part of the elastic media. Due to the deformation of elastic media, the electromagnetic waves is modified as a result of the element velocity. To consider the electromagnetic evolution, it is preferred to employ the Lagrangian method instead of the second Newton's law. Here, using an elastic frame, governing equations on opto-mechanical oscillations in an elastic media are derived. In a specific case, by comparing the results to the other methods, it shown that this method is more accurate because the exchange of electromagnetic waves by regarding the movement of the elastic media due to deform is considered.

Multilevel-3D Bit Patterned Magnetic Media with 8 Signal Levels Per Nanocolumn

PubMed Central

Amos, Nissim; Butler, John; Lee, Beomseop; Shachar, Meir H.; Hu, Bing; Tian, Yuan; Hong, Jeongmin; Garcia, Davil; Ikkawi, Rabee M.; Haddon, Robert C.; Litvinov, Dmitri; Khizroev, Sakhrat

2012-01-01

This letter presents an experimental study that shows that a 3rd physical dimension may be used to further increase information packing density in magnetic storage devices. We demonstrate the feasibility of at least quadrupling the magnetic states of magnetic-based data storage devices by recording and reading information from nanopillars with three magnetically-decoupled layers. Magneto-optical Kerr effect microscopy and magnetic force microscopy analysis show that both continuous (thin film) and patterned triple-stack magnetic media can generate eight magnetically-stable states. This is in comparison to only two states in conventional magnetic recording. Our work further reveals that ferromagnetic interaction between magnetic layers can be reduced by combining Co/Pt and Co/Pd multilayers media. Finally, we are showing for the first time an MFM image of multilevel-3D bit patterned media with 8 discrete signal levels. PMID:22808105

Multilevel-3D bit patterned magnetic media with 8 signal levels per nanocolumn.

PubMed

Amos, Nissim; Butler, John; Lee, Beomseop; Shachar, Meir H; Hu, Bing; Tian, Yuan; Hong, Jeongmin; Garcia, Davil; Ikkawi, Rabee M; Haddon, Robert C; Litvinov, Dmitri; Khizroev, Sakhrat

2012-01-01

This letter presents an experimental study that shows that a 3(rd) physical dimension may be used to further increase information packing density in magnetic storage devices. We demonstrate the feasibility of at least quadrupling the magnetic states of magnetic-based data storage devices by recording and reading information from nanopillars with three magnetically-decoupled layers. Magneto-optical Kerr effect microscopy and magnetic force microscopy analysis show that both continuous (thin film) and patterned triple-stack magnetic media can generate eight magnetically-stable states. This is in comparison to only two states in conventional magnetic recording. Our work further reveals that ferromagnetic interaction between magnetic layers can be reduced by combining Co/Pt and Co/Pd multilayers media. Finally, we are showing for the first time an MFM image of multilevel-3D bit patterned media with 8 discrete signal levels.

The Societal Curriculum and the School Curriculum: Allies or Antagonists?

ERIC Educational Resources Information Center

Cortes, Carlos E.

1979-01-01

The societal curriculum is that learned from family, peer groups, neighborhoods, mass media, and other socializing forces. Ways are suggested to use the societal curriculum in the classroom to increase critical awareness and analytical ability. (Author/MLF)

GOES-R Prelaunch News Conference

NASA Image and Video Library

2016-11-17

Clay Flinn, launch weather officer, 4th Weather Squadron, Cape Canaveral Air Force Station, speaks to members of the news media during a Geostationary Operational Environmental Satellite (GOES-R) prelaunch news conference in the Kennedy Space Center's Press Site auditorium in Florida.

Toward a Work-Force Analysis of the School Library Media Professional.

ERIC Educational Resources Information Center

Heim, Kathleen M.

1981-01-01

Summarizes general demographic and salary data to focus on entry levels, the current employment universe of school librarians, and the salary data for building-level librarians in 1979-80. More than 27 references are listed. (RAA)

Toward Theoretical Foundations of Resistive Force Theory of Granular-Structural Interaction, with Expansions to Flexible Locomotors

DTIC Science & Technology

2015-05-07

the proper depth-dependent pressure distribution before intruder motion begins. We model the intruder as a rigid surface within the granular body by...assigning corresponding planar nodes to move as a rigid body at a constant rate. This resembles a fully rough surface due to the no-slip condition, no...Stokesian fluids. Despite its remarkable capability to predict experimental locomotion and force distributions on mobile bodies in granular media, there is

DLVO, hydrophobic, capillary and hydrodynamic forces acting on bacteria at solid-air-water interfaces: Their relative impact on bacteria deposition mechanisms in unsaturated porous media.

PubMed

Bai, Hongjuan; Cochet, Nelly; Pauss, André; Lamy, Edvina

2017-02-01

Experimental and modeling studies were performed to investigate bacteria deposition behavior in unsaturated porous media. The coupled effect of different forces, acting on bacteria at solid-air-water interfaces and their relative importance on bacteria deposition mechanisms was explored by calculating Derjaguin-Landau-Verwey-Overbeek (DLVO) and non-DLVO interactions such as hydrophobic, capillary and hydrodynamic forces. Negatively charged non-motile bacteria and quartz sands were used in packed column experiments. The breakthrough curves and retention profiles of bacteria were simulated using the modified Mobile-IMmobile (MIM) model, to identify physico-chemical attachment or physical straining mechanisms involved in bacteria retention. These results indicated that both mechanisms might occur in both sand. However, the attachment was found to be a reversible process, because attachment coefficients were similar to those of detachment. DLVO calculations supported these results: the primary minimum did not exist, suggesting no permanent retention of bacteria to solid-water and air-water interfaces. Calculated hydrodynamic and resisting torques predicted that bacteria detachment in the secondary minimum might occur. The capillary potential energy was greater than DLVO, hydrophobic and hydrodynamic potential energies, suggesting that film straining by capillary forces might largely govern bacteria deposition under unsaturated conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Numerical model of two-dimensional heterogeneous combustion in porous media under natural convection or forced filtration

NASA Astrophysics Data System (ADS)

Lutsenko, Nickolay A.

2018-03-01

A novel mathematical model and original numerical method for investigating the two-dimensional waves of heterogeneous combustion in porous media are proposed and described in detail. The mathematical model is constructed within the framework of the model of interacting interpenetrating continua and includes equations of state, continuity, momentum conservation and energy for solid and gas phases. Combustion, considered in the paper, is due to the exothermic reaction between fuel in the porous solid medium and oxidiser contained in the gas flowing through the porous object. The original numerical method is based on a combination of explicit and implicit finite-difference schemes. A distinctive feature of the proposed model is that the gas velocity at the open boundaries (inlet and outlet) of the porous object is unknown and has to be found from the solution of the problem, i.e. the flow rate of the gas regulates itself. This approach allows processes to be modelled not only under forced filtration, but also under free convection, when there is no forced gas input in porous objects, which is typical for many natural or anthropogenic disasters (burning of peatlands, coal dumps, landfills, grain elevators). Some two-dimensional time-dependent problems of heterogeneous combustion in porous objects have been solved using the proposed numerical method. It is shown that two-dimensional waves of heterogeneous combustion in porous media can propagate in two modes with different characteristics, as in the case of one-dimensional combustion, but the combustion front can move in a complex manner, and gas dynamics within the porous objects can be complicated. When natural convection takes place, self-sustaining combustion waves can go through the all parts of the object regardless of where an ignition zone was located, so the all combustible material in each part of the object is burned out, in contrast to forced filtration.

Portable vapor diffusion coefficient meter

DOEpatents

Ho, Clifford K [Albuquerque, NM

2007-06-12

An apparatus for measuring the effective vapor diffusion coefficient of a test vapor diffusing through a sample of porous media contained within a test chamber. A chemical sensor measures the time-varying concentration of vapor that has diffused a known distance through the porous media. A data processor contained within the apparatus compares the measured sensor data with analytical predictions of the response curve based on the transient diffusion equation using Fick's Law, iterating on the choice of an effective vapor diffusion coefficient until the difference between the predicted and measured curves is minimized. Optionally, a purge fluid can forced through the porous media, permitting the apparatus to also measure a gas-phase permeability. The apparatus can be made lightweight, self-powered, and portable for use in the field.

Large Format Multifunction 2-Terabyte Optical Disk Storage System

NASA Technical Reports Server (NTRS)

Kaiser, David R.; Brucker, Charles F.; Gage, Edward C.; Hatwar, T. K.; Simmons, George O.

1996-01-01

The Kodak Digital Science OD System 2000E automated disk library (ADL) base module and write-once drive are being developed as the next generation commercial product to the currently available System 2000 ADL. Under government sponsorship with the Air Force's Rome Laboratory, Kodak is developing magneto-optic (M-O) subsystems compatible with the Kodak Digital Science ODW25 drive architecture, which will result in a multifunction (MF) drive capable of reading and writing 25 gigabyte (GB) WORM media and 15 GB erasable media. In an OD system 2000 E ADL configuration with 4 MF drives and 100 total disks with a 50% ration of WORM and M-O media, 2.0 terabytes (TB) of versatile near line mass storage is available.

Motion of deformable drops through granular media and other confined geometries.

PubMed

Davis, Robert H; Zinchenko, Alexander Z

2009-06-15

This article features recent simulation studies of the flow of emulsions containing deformable drops through pores, constrictions, and granular media. The flow is assumed to be at low Reynolds number, so that viscous forces dominate, and boundary-integral methods are used to determine interfacial velocities and, hence, track the drop motion and shapes. A single drop in a flat channel migrates to the channel centerplane due to deformation-induced drift, which increases its steady-state velocity along the channel. A drop moving towards a smaller interparticle constriction squeezes through the constriction if the capillary number (ratio of viscous deforming forces and interfacial tension forces) is large enough, but it becomes trapped when the capillary number is below a critical value. These concepts then influence the flow of an emulsion through a granular medium, for which the drop phase moves faster than the suspending liquid at large capillary numbers but slower than the suspending liquid at smaller capillary numbers. The permeabilities of the granular medium to both phases increase with increasing capillary number, due to the reduced resistance to squeezing of easily deformed drops, though drop breakup must also be considered at large capillary numbers.

A Stationary One-Equation Turbulent Model with Applications in Porous Media

NASA Astrophysics Data System (ADS)

de Oliveira, H. B.; Paiva, A.

2018-06-01

A one-equation turbulent model is studied in this work in the steady-state and with homogeneous Dirichlet boundary conditions. The considered problem generalizes two distinct approaches that are being used with success in the applications to model different flows through porous media. The novelty of the problem relies on the consideration of the classical Navier-Stokes equations with a feedback forces field, whose presence in the momentum equation will affect the equation for the turbulent kinetic energy (TKE) with a new term that is known as the production and represents the rate at which TKE is transferred from the mean flow to the turbulence. By assuming suitable growth conditions on the feedback forces field and on the function that describes the rate of dissipation of the TKE, as well as on the production term, we will prove the existence of the velocity field and of the TKE. The proof of their uniqueness is made by assuming monotonicity conditions on the feedback forces field and on the turbulent dissipation function, together with a condition of Lipschitz continuity on the production term. The existence of a unique pressure, will follow by the application of a standard version of de Rham's lemma.

Chapman-Enskog Analyses on the Gray Lattice Boltzmann Equation Method for Fluid Flow in Porous Media

NASA Astrophysics Data System (ADS)

Chen, Chen; Li, Like; Mei, Renwei; Klausner, James F.

2018-03-01

The gray lattice Boltzmann equation (GLBE) method has recently been used to simulate fluid flow in porous media. It employs a partial bounce-back of populations (through a fractional coefficient θ, which represents the fraction of populations being reflected by the solid phase) in the evolution equation to account for the linear drag of the medium. Several particular GLBE schemes have been proposed in the literature and these schemes are very easy to implement; but there exists uncertainty about the need for redefining the macroscopic velocity as there has been no systematic analysis to recover the Brinkman equation from the various GLBE schemes. Rigorous Chapman-Enskog analyses are carried out to show that the momentum equation recovered from these schemes can satisfy Brinkman equation to second order in ɛ only if θ = O( ɛ ) in which ɛ is the ratio of the lattice spacing to the characteristic length of physical dimension. The need for redefining macroscopic velocity is shown to be scheme-dependent. When a body force is encountered such as the gravitational force or that caused by a pressure gradient, different forms of forcing redefinitions are required for each GLBE scheme.

Low-resistive vibratory penetration in granular media.

PubMed

Darbois Texier, Baptiste; Ibarra, Alejandro; Melo, Francisco

2017-01-01

Non-cohesive materials such as sand, dry snow or cereals are encountered in various common circumstances, from everyday situations to industry. The process of digging into these materials remains a challenge to most animals and machines. Within the animal kingdom, different strategies are employed to overcome this issue, including excavation methods used by ants, the two-anchor strategy employed by soft burrowers such as razor-clams, and undulatory motions exhibited by sandfish lizards. Despite the development of technology to mimic these techniques in diggers and robots, the limitations of animals and machines may differ, and mimicry of natural processes is not necessarily the most efficient technological strategy. This study presents evidence that the resisting force for the penetration of an intruder into a dry granular media can be reduced by one order of magnitude with small amplitude (A ≃ 10 μm) and low frequency (f = 50 - 200 Hz) mechanical vibrations. This observed result is attributed to the local fluidization of the granular bed which induces the rupture of force chains. The drop in resistive force on entering dry granular materials may be relevant in technological development in order to increase the efficiency of diggers and robots.

InSight Prelaunch Overview

NASA Image and Video Library

2018-05-03

Members of the media and social media participants attended the NASA's Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, or InSight, prelaunch briefing at Vandenberg Air Force Base in California. The presentation focused on InSight Mars lander. InSight is scheduled for liftoff May 5, 2018, atop a United Launch Alliance (ULA) Atlas V rocket from Space Launch Complex 3 at Vandenberg. The spacecraft will be the first mission to look deep beneath the Martian surface studying the planet's interior by measuring its heat output and listen for marsquakes.

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

Jon Morse, Director, Astrophysics Division, at NASA Headquarters, left, talks about the Kepler mission during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Morse was joined at the briefing by William Borucki, principal investigator for Kepler Science at Ames Research Center, second left, Jim Fanson, Kepler Project Manager at the Jet Propulsion Laboratory and Debra Fischer, professor of Astronomy at San Francisco State University, right. Kepler is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Photo Credit: (NASA/Paul. E. Alers)

Forward Deployment of U.S. Naval Forces to Australia

DTIC Science & Technology

2007-12-14

and commentary, not only mass media products but also periodic reports governmental and other organizations focused on international relations, are......professor and former CIA psychologist Jerrold Post, “has the core characteristics of the most dangerous personality disorder, malignant narcissism

Sensor and Processing COI (Briefing Charts)

DTIC Science & Technology

2014-05-27

Persistent Surveillance • Target Detection, Recognition & ID at Standoff Ranges • Force/Platform/Sensor Protection • Target Tracking • Early Warning • BDA ...inhomogeneous and complex media is also a foundational challenge for President’s BRAIN initiative. 38 Explore Advanced Sensors And Processing

Media Matters.

ERIC Educational Resources Information Center

Neie, Van E.

1983-01-01

Describes "The Kinetic Karnival of Jearl Walker," six 30-minute television programs. Programs focus on: forces/collisions; rotation; fluid flow and friction; viscosity; Leidenfrost effect; and the science of cooking. Teacher's manual containing description, class preparation, questions, and bibliography are provided with each program (available in…

KSC-2014-2079

NASA Image and Video Library

2014-04-14

CAPE CANAVERAL, Fla. - Social media representatives get an up-close view of the SpaceX Falcon 9 rocket and Dragon Capsule on Space Launch Complex 40 on Cape Canaveral Air Force Station in Florida. NASA Social participants are given the same access as news media in an effort to align the experience of social media representatives with those of traditional media, including the opportunity to view a launch of SpaceX’s Falcon 9 rocket, tour NASA facilities at Kennedy Space Center, speak with representatives from both NASA and SpaceX, view and take photographs of the SpaceX launch pad, meet fellow space enthusiasts who are active on social media and meet members of SpaceX and NASA's social media teams. Scheduled for launch at about 4:58 p.m. EDT April 14, Dragon will be making its fourth trip to the space station. The SpaceX-3 mission, carrying almost 2.5 tons of supplies, technology and science experiments, is the third of 12 flights under NASA's Commercial Resupply Services contract to resupply the orbiting laboratory. For more information, visit http://www.nasa.gov/mission_pages/station/structure/launch/index.html Photo credit: NASA/Glenn Benson

KSC-2014-2075

NASA Image and Video Library

2014-04-14

CAPE CANAVERAL, Fla. - Social media representatives get an up-close view of the SpaceX Falcon 9 rocket and Dragon Capsule on Space Launch Complex 40 on Cape Canaveral Air Force Station in Florida. NASA Social participants are given the same access as news media in an effort to align the experience of social media representatives with those of traditional media, including the opportunity to view a launch of SpaceX’s Falcon 9 rocket, tour NASA facilities at Kennedy Space Center, speak with representatives from both NASA and SpaceX, view and take photographs of the SpaceX launch pad, meet fellow space enthusiasts who are active on social media and meet members of SpaceX and NASA's social media teams. Scheduled for launch at about 4:58 p.m. EDT April 14, Dragon will be making its fourth trip to the space station. The SpaceX-3 mission, carrying almost 2.5 tons of supplies, technology and science experiments, is the third of 12 flights under NASA's Commercial Resupply Services contract to resupply the orbiting laboratory. For more information, visit http://www.nasa.gov/mission_pages/station/structure/launch/index.html Photo credit: NASA/Glenn Benson

Experimental development of a Nusselt correlation for forced reciprocating oscillated vertical annular glycerol flow through a porous domain

NASA Astrophysics Data System (ADS)

Sayar, Ersin

2017-07-01

The objective of this paper is to investigate the heat transfer to oscillating annular flow of a viscous fluid. The flow media includes stationary stainless steel wool porous domain and glycerol as the working fluid. The effects of actuation frequency and wall heat flux on the temperature field and resultant heat convection coefficient are studied. The temperature values at radial direction are close each other as porous media mixes the glycerol successfully. A correlation with a functional dependence to kinetic Reynolds number is recommended that can be used to acquire the averaged heat transfer for oscillating flows. Present experimental results with glycerol in a porous media are compared to the published experimental works with water. For the limited case of the two working fluids, Nusselt number is normalized well using the Prandtl number (Pr0.67). Results are also compared to non-porous media study and heat transfer is found to increase up to a factor of five in porous media. The recommended correlation is claimed to have a significant role for anticipating heat transfer of oscillating viscous fluid not only at low frequencies but also at low heat fluxes in a porous and permeable solid media.

Collisional model of the drag force of granular impact

NASA Astrophysics Data System (ADS)

Stevens Bester, Cacey; Behringer, Robert P.

2017-06-01

A dense, dry granular target can cause a free-falling intruding object to come to an abrupt stop as its momentum is lost to the grains. An empirical force law describes this process, characterizing the stopping force as the sum of depth-dependent friction and velocity-dependent inertial drag. However, a complete interpretation of the stopping force, incorporating grain-scale interactions during impact, remains unresolved. Here, the momentum transfer is proposed to occur through sporadic, normal collisions with clusters of high force-carrying grains at the intruder's surface. To test this model in impact experiments, we determine the forces acting on an intruder decelerating through a dense granular medium using high-speed imaging of its trajectory. We vary the geometry of the impacting object to infer intruder-grain interactions. As a result, we connect the inertial drag to the effect of intruder shape based on the proposed collisional model. These impact studies serve as an approach to understand dynamic force transmission in granular media.

Measured long-range repulsive Casimir-Lifshitz forces.

PubMed

Munday, J N; Capasso, Federico; Parsegian, V Adrian

2009-01-08

Quantum fluctuations create intermolecular forces that pervade macroscopic bodies. At molecular separations of a few nanometres or less, these interactions are the familiar van der Waals forces. However, as recognized in the theories of Casimir, Polder and Lifshitz, at larger distances and between macroscopic condensed media they reveal retardation effects associated with the finite speed of light. Although these long-range forces exist within all matter, only attractive interactions have so far been measured between material bodies. Here we show experimentally that, in accord with theoretical prediction, the sign of the force can be changed from attractive to repulsive by suitable choice of interacting materials immersed in a fluid. The measured repulsive interaction is found to be weaker than the attractive. However, in both cases the magnitude of the force increases with decreasing surface separation. Repulsive Casimir-Lifshitz forces could allow quantum levitation of objects in a fluid and lead to a new class of switchable nanoscale devices with ultra-low static friction.

From Red Cells to Soft Porous Lubrication

NASA Astrophysics Data System (ADS)

Gacka, T.; Nathan, R.; Wu, L.; Wu, Q.; Cbmss Laboratory Team; Chinese Academy Of Sci. Team

2011-11-01

Feng and Weinbaum (J. Fluid. Mech., 422, 282, 2000), inspired by the enhanced lift phenomena in downhill skiing, developed a new lubrication theory for highly compressible porous media where significantly increased lifting force was predicted as a planing surface glided over a soft porous layer; suggesting superior potential use of porous media for soft lubrication. In this study, we experimentally examine the lift generation phenomena by developing a novel soft porous bearing that consists of a running conveyer belt covered with a soft, 100% polyester, porous sheet, and a stationary, fully instrumented, inclined, planar, upper board. Pore pressure was generated as the upper boundary glides over the soft porous bearing and was measured by pressure sensors. One observed that the pore pressure distribution is consistent with predictions by Feng and Weinbaum (2000), and is a function of the relative velocity between the planing surface and the running belt, the mechanical properties (e.g. porosity, permeability and stiffness) and thickness of the porous layer, as well as the compression ratios at the leading and trailing edges. A load cell is used to characterize the performance of the porous bearing, by comparing pore pressure to total lifting forces. The study presented herein significantly improves our understanding of the behavior of highly compressible porous media under fast compression.

Shock Effect or Ships Passing in the Night: The Role of Armored Forces in Fourth Generation Warfare

DTIC Science & Technology

2003-06-23

effects- based planning, by immediately making clear the limitations and constraints of the use of such force. It is certain that as an instrument of the...advantage of the weaknesses of disorder; conversely, disorder takes advantage of the weaknesses of order. Based upon the strategic aims of the...generations of war with their overlapping political, economic, social , military, and mass media arenas makes determining the type of war we are entering more

The Emergence of a Content Acceptance Model (CAM): New Thoughts Regarding the Trial, Adoption, and Usage of New Media

DTIC Science & Technology

2009-03-26

child vi Acknowledgments I took on this thesis as a challenge to myself for two reasons. First, I wanted to complete a thesis outside my...first child . I also need to think all my previous Wing Commander, Air Force squadron commanders, previous teachers, and other Air Force leaders...their mind 18: Phishers, spammers, and porn agencies send out messages trying to make money 17: To stay connected with family/friends all over nation

Calculation of Hamaker constants in non-aqueous fluid media

DOE Office of Scientific and Technical Information (OSTI.GOV)

BELL,NELSON S.; DIMOS,DUANE B.

2000-05-09

Calculations of the Hamaker constants representing the van der Waals interactions between conductor, resistor and dielectric materials are performed using Lifshitz theory. The calculation of the parameters for the Ninham-Parsegian relationship for several non-aqueous liquids has been derived based on literature dielectric data. Discussion of the role of van der Waals forces in the dispersion of particles is given for understanding paste formulation. Experimental measurements of viscosity are presented to show the role of dispersant truncation of attractive van der Waals forces.

Micro-blogs, online forums, and the birth-control policy: social media and the politics of reproduction in China.

PubMed

Shi, Lihong

2014-03-01

In June 2012, the news of a Chinese woman's forced late-term abortion quickly spread across the internet in China. Graphic photos of the woman with the aborted fetus provoked public outrage and widespread condemnation on social media sites. In the aftermath, local authorities apologized, seven officials were given demerits, and the couple received monetary compensation. This case was put under the spotlight mainly because of the exposure of the story by family members of the woman through social media and the resulting public outcry in cyberspace. Following the disclosure of this story and public reactions online, this article explores the complex interplays among different layers of state power, the individual, and the public in reproductive politics, and discusses the ways in which social media has been utilized to resist state control of reproduction. By delving into the nuanced interactions among layers of state authorities, this article sheds light on the study of state-society relations in reproductive politics. It also calls attention to the role that social media plays in reproductive issues.

Does the media matter to suicide?: Examining the social dynamics surrounding media reporting on suicide in a suicide-prone community.

PubMed

Mueller, Anna S

2017-05-01

Despite the widespread acknowledgement by public health organizations that media reporting matters to suicide, this link has been much debated and the mechanisms undergirding it poorly understood. With this study, I combine a media analysis with ethnographic data collected during 2014-2016 (N = 91) to examine the social dynamics surrounding media reporting on suicide in a community (that I call Poplar Grove, USA) with an enduring adolescent suicide problem. I illustrate how the media crafted a particular story about why youth die by suicide that emphasized academic pressure over other plausible causes. In so doing, the media may have broadened ideas about when suicide is seen as an option. However, I also provide evidence that cautions against attributing too much causal power to the media. The media coverage in Poplar Grove reflected conditions that were already present in the community; it was already a high-pressure place for youth to live with widespread mental health stigma. These factors likely shaped media reporting, while also contributing independently to the suicide problem. Finally, I found that the suicide deaths that received media coverage were those that triggered significant cognitive dissonance and thus were much discussed among youth, independent of the media reporting. This generated ample opportunities for peer role modeling of suicide. Thus, while the media may have helped solidify a certain view of suicide in the community, it was not the only social force contributing to suicide in Poplar Grove. While the findings from this study do not negate the importance of responsible reporting on suicide, they do contextualize the role of the media in suicide and suggest that researchers must take a broader view of how suicide suggestion operates in the media and in social contexts. Copyright © 2017 Elsevier Ltd. All rights reserved.

News Media Industry

DTIC Science & Technology

2006-01-01

technology, changing consumer behavior and increased pressure for profitability. These three forces are the catalysts of change and have pushed the...model in order to compete. Consumer Behavior : Changes in consumer behavior began with the growth of broadcast television in the 1960’s and 70’s

36 CFR 1275.16 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... pictures, sound and video recordings, machine-readable media, plats, maps, models, pictures, works of art... retained or appropriate for retention as evidence of or information about these powers or duties. Included... Activities or the Watergate Special Prosecution Force; or (2) Are circumscribed in the Articles of...

36 CFR 1275.16 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... pictures, sound and video recordings, machine-readable media, plats, maps, models, pictures, works of art... retained or appropriate for retention as evidence of or information about these powers or duties. Included... Activities or the Watergate Special Prosecution Force; or (2) Are circumscribed in the Articles of...

36 CFR 1275.16 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... pictures, sound and video recordings, machine-readable media, plats, maps, models, pictures, works of art... retained or appropriate for retention as evidence of or information about these powers or duties. Included... Activities or the Watergate Special Prosecution Force; or (2) Are circumscribed in the Articles of...

36 CFR 1275.16 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... pictures, sound and video recordings, machine-readable media, plats, maps, models, pictures, works of art... retained or appropriate for retention as evidence of or information about these powers or duties. Included... Activities or the Watergate Special Prosecution Force; or (2) Are circumscribed in the Articles of...

Accelerating Adaptation of Natural Resource Management to Address Climate Change

PubMed Central

Cross, Molly S; McCarthy, Patrick D; Garfin, Gregg; Gori, David; Enquist, Carolyn AF

2013-01-01

Abstract Natural resource managers are seeking tools to help them address current and future effects of climate change. We present a model for collaborative planning aimed at identifying ways to adapt management actions to address the effects of climate change in landscapes that cross public and private jurisdictional boundaries. The Southwest Climate Change Initiative (SWCCI) piloted the Adaptation for Conservation Targets (ACT) planning approach at workshops in 4 southwestern U.S. landscapes. This planning approach successfully increased participants’ self-reported capacity to address climate change by providing them with a better understanding of potential effects and guiding the identification of solutions. The workshops fostered cross-jurisdictional and multidisciplinary dialogue on climate change through active participation of scientists and managers in assessing climate change effects, discussing the implications of those effects for determining management goals and activities, and cultivating opportunities for regional coordination on adaptation of management plans. Facilitated application of the ACT framework advanced group discussions beyond assessing effects to devising options to mitigate the effects of climate change on specific species, ecological functions, and ecosystems. Participants addressed uncertainty about future conditions by considering more than one climate-change scenario. They outlined opportunities and identified next steps for implementing several actions, and local partnerships have begun implementing actions and conducting additional planning. Continued investment in adaptation of management plans and actions to address the effects of climate change in the southwestern United States and extension of the approaches used in this project to additional landscapes are needed if biological diversity and ecosystem services are to be maintained in a rapidly changing world. Acelerando la Adaptación del Manejo de Recursos Naturales para Atender el Cambio Climático Resumen Los manejadores de recursos naturales están buscando herramientas para ayudarles a atender los efectos actuales y futuros del cambio climático. Presentamos un modelo para la planificación colaborativa enfocada a identificar formas para adaptar las acciones de manejo para atender los efectos del cambio climático en paisajes que cruzan límites jurisdiccionales públicos y privados. La Iniciativa Sudoccidental de Cambio Climático (ISCC) puso a prueba el método de planificación de Adaptación para Metas de Conservación (AMC) en talleres en cuatro paisajes del suroeste de E. U. A. Este método de planificación incrementó exitosamente la capacidad de los participantes para atender el cambio climático al proporcionarles un mejor entendimiento de los efectos potenciales y guiar la identificación de soluciones. Los talleres promovieron el diálogo trans-jurisdiccional y multidisciplinario sobre cambio climático mediante la participación activa de científicos y manejadores en la evaluación de efectos del cambio climático, la discusión de implicaciones de esos efectos para determinar las metas y actividades de manejo y desarrollar oportunidades para la coordinación regional de la adaptación de planes de manejo. La aplicación simplificada del marco AMC llevó las discusiones de grupo más allá de la evaluación de los efectos a la concepción de opciones para mitigar los efectos del cambio climático sobres determinadas especies, funciones ecológicas y ecosistemas. Los participantes abordaron la incertidumbre de las condiciones futuras al considerar más de un escenario de cambio climático. Delinearon oportunidades e identificaron los siguientes pasos para la implementación de varias acciones, y asociaciones locales han comenzado a implementar acciones y realizar planificación adicional. Se requiere inversión continua en la adaptación de planes y acciones de manejo para atender los efectos del cambio climático en el suroeste de Estados Unidos y la extensión de los métodos utilizados en este proyecto en paisajes adicionales si se quiere mantener la diversidad biológica y los servicios de los ecosistemas en un mundo que cambia rápidamente. PMID:23110636

A lattice Boltzmann investigation of steady-state fluid distribution, capillary pressure and relative permeability of a porous medium: Effects of fluid and geometrical properties

NASA Astrophysics Data System (ADS)

Li, Zi; Galindo-Torres, Sergio; Yan, Guanxi; Scheuermann, Alexander; Li, Ling

2018-06-01

Simulations of simultaneous steady-state two-phase flow in the capillary force-dominated regime were conducted using the state-of-the-art Shan-Chen multi-component lattice Boltzmann model (SCMC-LBM) based on two-dimensional porous media. We focused on analyzing the fluid distribution (i.e., WP fluid-solid, NP fluid-solid and fluid-fluid interfacial areas) as well as the capillary pressure versus saturation curve which was affected by fluid and geometrical properties (i.e., wettability, adhesive strength, pore size distribution and specific surface area). How these properties influenced the relative permeability versus saturation relation through apparent effective permeability and threshold pressure gradient was also explored. The SCMC-LBM simulations showed that, a thin WP fluid film formed around the solid surface due to the adhesive fluid-solid interaction, resulting in discrete WP fluid distributions and reduction of the WP fluid mobility. Also, the adhesive interaction provided another source of capillary pressure in addition to capillary force, which, however, did not affect the mobility of the NP fluid. The film fluid effect could be enhanced by large adhesive strength and fine pores in heterogeneous porous media. In the steady-state infiltration, not only the NP fluid but also the WP fluid were subjected to the capillary resistance. The capillary pressure effect could be alleviated by decreased wettability, large average pore radius and improved fluid connectivity in heterogeneous porous media. The present work based on the SCMC-LBM investigations elucidated the role of film fluid as well as capillary pressure in the two-phase flow system. The findings have implications for ways to improve the macroscopic flow equation based on balance of force for the steady-state infiltration.

Analytical and Computational Modeling of Mechanical Waves in Microscale Granular Crystals: Nonlinearity and Rotational Dynamics

NASA Astrophysics Data System (ADS)

Wallen, Samuel P.

Granular media are one of the most common, yet least understood forms of matter on earth. The difficulties in understanding the physics of granular media stem from the fact that they are typically heterogeneous and highly disordered, and the grains interact via nonlinear contact forces. Historically, one approach to reducing these complexities and gaining new insight has been the study of granular crystals, which are ordered arrays of similarly-shaped particles (typically spheres) in Hertzian contact. Using this setting, past works explored the rich nonlinear dynamics stemming from contact forces, and proposed avenues where such granular crystals could form designer, dynamically responsive materials, which yield beneficial functionality in dynamic regimes. In recent years, the combination of self-assembly fabrication methods and laser ultrasonic experimental characterization have enabled the study of granular crystals at microscale. While our intuition may suggest that these microscale granular crystals are simply scaled-down versions of their macroscale counterparts, in fact, the relevant physics change drastically; for example, short-range adhesive forces between particles, which are negligible at macroscale, are several orders of magnitude stronger than gravity at microscale. In this thesis, we present recent advances in analytical and computational modeling of microscale granular crystals, in particular concerning the interplay of nonlinearity, shear interactions, and particle rotations, which have previously been either absent, or included separately at macroscale. Drawing inspiration from past works on phononic crystals and nonlinear lattices, we explore problems involving locally-resonant metamaterials, nonlinear localized modes, amplitude-dependent energy partition, and other rich dynamical phenomena. This work enhances our understanding of microscale granular media, which may find applicability in fields such as ultrasonic wave tailoring, signal processing, shock and vibration mitigation, and powder processing.

Correlative Magnetic Imaging of Heat-Assisted Magnetic Recording Media in Cross Section Using Lorentz TEM and MFM

DOE PAGES

Kim, Taeho Roy; Phatak, Charudatta; Petford-Long, Amanda K.; ...

2017-10-23

In order to increase the storage density of hard disk drives, a detailed understanding of the magnetic structure of the granular magnetic layer is essential. Here, we demonstrate an experimental procedure of imaging recorded bits on heat-assisted magnetic recording (HAMR) media in cross section using Lorentz transmission electron microscopy (TEM). With magnetic force microscopy and focused ion beam (FIB), we successfully targeted a single track to prepare cross-sectional TEM specimens. Then, we characterized the magnetic structure of bits with their precise location and orientation using Fresnel mode of Lorentz TEM. Here, this method can promote understanding of the correlation betweenmore » bits and their material structure in HAMR media to design better the magnetic layer.« less

Correlative Magnetic Imaging of Heat-Assisted Magnetic Recording Media in Cross Section Using Lorentz TEM and MFM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Taeho Roy; Phatak, Charudatta; Petford-Long, Amanda K.

In order to increase the storage density of hard disk drives, a detailed understanding of the magnetic structure of the granular magnetic layer is essential. Here, we demonstrate an experimental procedure of imaging recorded bits on heat-assisted magnetic recording (HAMR) media in cross section using Lorentz transmission electron microscopy (TEM). With magnetic force microscopy and focused ion beam (FIB), we successfully targeted a single track to prepare cross-sectional TEM specimens. Then, we characterized the magnetic structure of bits with their precise location and orientation using Fresnel mode of Lorentz TEM. Here, this method can promote understanding of the correlation betweenmore » bits and their material structure in HAMR media to design better the magnetic layer.« less

NekNominate: Social Norms, Social Media, and Binge Drinking.

PubMed

Wombacher, Kevin; Reno, Jenna E; Veil, Shari R

2017-05-01

This study examines the social-media-based binge drinking game NekNominate and how this phenomenon is related to social norms. NekNominate is a game wherein players are nominated to film themselves "neking" or chugging copious amounts of alcohol or drinking alcohol in a novel or humorous manner. The player then nominates other players via social media who then have a specific timeframe in which they must complete their challenge or face ridicule. Health communication research on drinking behaviors has often looked at the role of social norms in determining these behaviors. News stories (n = 44) of NekNominate and tweets (n = 851) culled using the hashtag #NekNominate during three different time periods are analyzed to identify the normative forces at play in this recent phenomenon.

Depth-dependent resistance of granular media to vertical penetration.

PubMed

Brzinski, T A; Mayor, P; Durian, D J

2013-10-18

We measure the quasistatic friction force acting on intruders moving downwards into a granular medium. By utilizing different intruder geometries, we demonstrate that the force acts locally normal to the intruder surface. By altering the hydrostatic loading of grain contacts by a sub-fluidizing airflow through the bed, we demonstrate that the relevant frictional contacts are loaded by gravity rather than by the motion of the intruder itself. Lastly, by measuring the final penetration depth versus airspeed and using an earlier result for inertial drag, we demonstrate that the same quasistatic friction force acts during impact. Altogether this force is set by a friction coefficient, hydrostatic pressure, projectile size and shape, and a dimensionless proportionality constant. The latter is the same in nearly all experiments, and is surprisingly greater than one.

Social media, help or hindrance: what role does social media play in young people's mental health?

PubMed

Lloyd, Alfie

2014-11-01

Social media is a huge force in the lives of young people with wide ranging effects on their development; given the importance of adolescence in the genesis of mental illness, social media is a factor in the mental health of young people. Despite the role that social media obviously plays in the development of mental illness, little research has been done into the impact that social media has on in the mental illness of young people. In general, what research there is points towards social media having a large impact on young people in both positive and negative ways. In particular, certain studies show a greater incidence and severity of bullying online compared to offline which may contribute to the development of depression. This contrasts with the positive impact that social media seems to have for young people in minority groups (ethnic minorities and those with chronic disease or disability) by allowing them to connect with others who live similar lives despite geographical separation. This acts as a positive influence in these people's lives though a direct link to mental illness was not shown. Overall, several important issues are raised: firstly, the lack of research that has been conducted in the area; secondly, the gulf that exists between the generation of younger, 'digital native' generations and the older generations who are not as engaged with social media; and finally, the huge potential that exists for the use of social media as a protective influence for adolescents. With proper engagement, policy makers and health professionals could use social media to connect with young people on issues like mental health.

Fabrication of oriented crystals as force measurement tips via focused ion beam and microlithography methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Zhigang; Chun, Jaehun; Chatterjee, Sayandev

Detailed knowledge of the forces between nanocrystals is very crucial for understanding many generic (e.g., random aggregation/assembly and rheology) and specific (e.g., oriented attachment) phenomena at macroscopic length scales, especially considering the additional complexities involved in nanocrystals such as crystal orientation and corresponding orientation-dependent physicochemical properties. Because there are a limited number of methods to directly measure the forces, little is known about the forces that drive the various emergent phenomena. Here we report on two methods of preparing crystals as force measurement tips used in an atomic force microscope (AFM): the focused ion beam method and microlithography method. Themore » desired crystals are fabricated using these two methods and are fixed to the AFM probe using platinum deposition, ultraviolet epoxy, or resin, which allows for the orientation-dependent force measurements. These two methods can be used to attach virtually any solid particles (from the size of a few hundreds of nanometers to millimeters). We demonstrate the force measurements between aqueous media under different conditions such as pH.« less

Estudio de los Efectos Gravitomagnéticos en Cuerpos Masivos Rotantes

NASA Astrophysics Data System (ADS)

Velandia Heredia, N.; Tejeiro, J. M.

2008-03-01

A partir del estudio de los Efectos Gravitomagnéticos en cuerpos masivos rotantes, planteamos la expresión para medir el desfase en el tiempo, para diferentes observadores, que se dan cuando viajan dos rayos de luz por una guía de onda o de manera libre (geodésicas), en el plano azimutal y en el plano polar. Con lo anterior queremos abordar el experimento tipo Michelson y Morley, de forma que podamos involucrar el valor de la densidad del momento angular (a) en el retraso temporal para los dos haces de luz que viajan por los brazos del interferómetro, cuando este último es ubicado en el plano ecuatorial.

[Dehiberations over the semantics of mass communication media].

PubMed

Martines, R

1975-09-12

The radio, cinema and T.V. have developed their own idiolects and aesthetic standards. These in turn have influenced social relationships and education. Their effect is the reduction of society to a common mass, in which no attentuon is paid to individual motive forces.

36 CFR § 1275.16 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... pictures, sound and video recordings, machine-readable media, plats, maps, models, pictures, works of art... retained or appropriate for retention as evidence of or information about these powers or duties. Included... Activities or the Watergate Special Prosecution Force; or (2) Are circumscribed in the Articles of...

32 CFR 989.24 - Public notification.

Code of Federal Regulations, 2010 CFR

2010-07-01

... National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.24 Public notification. (a) Except as provided in § 989.26... limit local notification to the SPOC, local government representatives, and local news media. For all...

32 CFR 989.24 - Public notification.

Code of Federal Regulations, 2013 CFR

2013-07-01

... National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.24 Public notification. (a) Except as provided in § 989.26... limit local notification to the SPOC, local government representatives, and local news media. For all...

32 CFR 989.24 - Public notification.

Code of Federal Regulations, 2012 CFR

2012-07-01

... National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.24 Public notification. (a) Except as provided in § 989.26... limit local notification to the SPOC, local government representatives, and local news media. For all...

32 CFR 989.24 - Public notification.

Code of Federal Regulations, 2011 CFR

2011-07-01

... National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.24 Public notification. (a) Except as provided in § 989.26... limit local notification to the SPOC, local government representatives, and local news media. For all...

32 CFR 989.24 - Public notification.

Code of Federal Regulations, 2014 CFR

2014-07-01

... National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ENVIRONMENTAL PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.24 Public notification. (a) Except as provided in § 989.26... limit local notification to the SPOC, local government representatives, and local news media. For all...

KSC-2015-1222

NASA Image and Video Library

2015-01-28

VANDENBERG AIR FORCE BASE, Calif. – From left, John Bellardo, co-principal investigator Cubesat at California Polytechnic, San Luis Obispo, David Rider, GRIFEX principal investigator at Jet Propulsion Laboratory, Pasadena, California, and Dave Klumpar, Firebird-II principal investigator and director of the Space Science and Engineering Laboratory at Montana State University in Bozeman, Montana, discuss three Educational Launch of Nanosatellites ELaNa CubeSat that are being flown as auxiliary payloads on NASA's Soil Moisture Active Passive mission, or SMAP, with the audience of a NASA Social held for at Vandenberg Air Force Base in California. This NASA Social brought together mission scientists and engineers with an audience of 70 students, educators, social media managers, bloggers, photographers and videographers who were selected from a pool of 325 applicants from 45 countries to participate in launch activities and communicate their experience with social media followers. The SMAP mission is scheduled to launch from Vandenberg on Jan. 29. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Kim Shiflett

Rolling Tobacco in Banana Leaves, Newspaper, or Copybook Paper Associated With Significant Reduction in Lung Function in Vanuatu.

PubMed

Weitz, Charles A; Olszowy, Kathryn M; Dancause, Kelsey N; Sun, Cheng; Pomer, Alysa; Silverman, Howard; Lee, G; Tarivonda, Len; Chan, Chim W; Kaneko, Akira; Lum, J K; Garruto, Ralph M

2017-04-01

In addition to the widespread availability of packaged cigarettes, the inhabitants of island nations of the Southwest Pacific frequently smoke commercially available loose tobacco using manufactured rolling papers, as well as locally grown tobacco rolled in manufactured rolling paper or wrapped in leaves, copybook paper, and newspaper. In this study, Vanuatu men who smoked local tobacco rolled in leaves, copybook paper, or newspaper showed significantly lower forced vital capacity (FVC), forced expiratory volume in 1 second (FEV 1 ), and FEV 1 /FVC ratios than men who smoked packaged cigarettes, store-bought tobacco rolled in manufactured rolling paper, or who smoked locally grown tobacco rolled in manufactured rolling papers. The addition of toxins from these unusual tobacco-wrapping media produces lung function deficits similar to the pattern noted among tobacco smokers who also inhale smoke from burning biomass. Thus, public health initiatives should consider including strategies addressing the use of wrapping media among smokers in South Pacific island societies.

Impact of projectiles of different geometries on dry granular media using DEM simulations

NASA Astrophysics Data System (ADS)

Vajrala, Spandana; Bagheri, Hosain; Emady, Heather; Marvi, Hamid; Particulate Process; Product Design Group Team; Birth Lab Collaboration

Recently, several studies involving numerical and experimental methods have focused on the study of impact dynamics in both dry and wet granular media. Most of these studies considered the impact of spherical projectiles under different conditions, while representative models could involve more complex shapes. Examples include such things as an animal's foot impacting sand or an asteroid hitting the ground. Dropping different shaped geometries with conserved density, volume and velocity on a granular bed may experience contrasting drag forces upon penetration. This is the result of the difference in the surface areas coming in contact with the granular media. Therefore, this work will utilize three-dimensional Discrete Element Modelling (DEM) simulations to observe and compare the impact of different geometries like cylinder and cuboid of same material properties and volume. These geometries will be impacted on a loosely packed non-cohesive dry granular bed with the same impact velocities where the effect of surface area in contact with the granular media will be analyzed upon impact and penetration.

Super-Coulombic atom–atom interactions in hyperbolic media

PubMed Central

Cortes, Cristian L.; Jacob, Zubin

2017-01-01

Dipole–dipole interactions, which govern phenomena such as cooperative Lamb shifts, superradiant decay rates, Van der Waals forces and resonance energy transfer rates, are conventionally limited to the Coulombic near-field. Here we reveal a class of real-photon and virtual-photon long-range quantum electrodynamic interactions that have a singularity in media with hyperbolic dispersion. The singularity in the dipole–dipole coupling, referred to as a super-Coulombic interaction, is a result of an effective interaction distance that goes to zero in the ideal limit irrespective of the physical distance. We investigate the entire landscape of atom–atom interactions in hyperbolic media confirming the giant long-range enhancement. We also propose multiple experimental platforms to verify our predicted effect with phonon–polaritonic hexagonal boron nitride, plasmonic super-lattices and hyperbolic meta-surfaces as well. Our work paves the way for the control of cold atoms above hyperbolic meta-surfaces and the study of many-body physics with hyperbolic media. PMID:28120826

Using hydrogels in microscopy: A tutorial.

PubMed

Flood, Peter; Page, Henry; Reynaud, Emmanuel G

2016-05-01

Sample preparation for microscopy is a crucial step to ensure the best experimental outcome. It often requires the use of specific mounting media that have to be tailored to not just the sample but the chosen microscopy technique. The media must not damage the sample or impair the optical path, and may also have to support the correct physiological function/development of the sample. For decades, researchers have used embedding media such as hydrogels to maintain samples in place. Their ease of use and transparency has promoted them as mainstream mounting media. However, they are not as straightforward to implement as assumed. They can contain contaminants, generate forces on the sample, have complex diffusion and structural properties that are influenced by multiple factors and are generally not designed for microscopy in mind. This short review will discuss the advantages and disadvantages of using hydrogels for microscopy sample preparation and highlight some of the less obvious problems associated with the area. Copyright © 2016 Elsevier Ltd. All rights reserved.

Super-Coulombic atom-atom interactions in hyperbolic media

NASA Astrophysics Data System (ADS)

Cortes, Cristian L.; Jacob, Zubin

2017-01-01

Dipole-dipole interactions, which govern phenomena such as cooperative Lamb shifts, superradiant decay rates, Van der Waals forces and resonance energy transfer rates, are conventionally limited to the Coulombic near-field. Here we reveal a class of real-photon and virtual-photon long-range quantum electrodynamic interactions that have a singularity in media with hyperbolic dispersion. The singularity in the dipole-dipole coupling, referred to as a super-Coulombic interaction, is a result of an effective interaction distance that goes to zero in the ideal limit irrespective of the physical distance. We investigate the entire landscape of atom-atom interactions in hyperbolic media confirming the giant long-range enhancement. We also propose multiple experimental platforms to verify our predicted effect with phonon-polaritonic hexagonal boron nitride, plasmonic super-lattices and hyperbolic meta-surfaces as well. Our work paves the way for the control of cold atoms above hyperbolic meta-surfaces and the study of many-body physics with hyperbolic media.

High bandwidth piezoresistive force probes with integrated thermal actuation

PubMed Central

Doll, Joseph C.; Pruitt, Beth L.

2012-01-01

We present high-speed force probes with on-chip actuation and sensing for the measurement of pN-scale forces at the microsecond time scale. We achieve a high resonant frequency in water (1–100 kHz) with requisite low spring constants (0.3–40 pN/nm) and low integrated force noise (1–100 pN) by targeting probe dimensions on the order of 300 nm thick, 1–2 μm wide and 30–200 μm long. Forces are measured using silicon piezoresistors while the probes are actuated thermally with an aluminum unimorph and silicon heater. The piezoresistive sensors are designed using open source numerical optimization code that incorporates constraints on operating temperature. Parylene passivation enables operation in ionic media and we demonstrate simultaneous actuation and sensing. The improved design and fabrication techniques that we describe enable a 10–20 fold improvement in force resolution or measurement bandwidth over prior piezoresistive cantilevers of comparable thickness. PMID:23175616

The injured mind in the UK Armed Forces

PubMed Central

Greenberg, N.; Jones, E.; Jones, N.; Fear, N. T.; Wessely, S.

2011-01-01

The mental health of the UK Armed Forces is a topic much debated by healthcare professionals, politicians and the media. While the current operations in Afghanistan, and the recent conflict in Iraq, are relevant to this debate, much of what is known about the effects of war upon the psyche still derives from the two World Wars. This paper will examine the historical and contemporary evidence about why it is that some Service personnel suffer psychological injuries during their military service and others do not. The paper will also consider some of the strategies that today's Armed Forces have put in place to mitigate the effects of sending military personnel into danger. PMID:21149361

Depinning of an anisotropic interface in random media: The tilt effect

NASA Astrophysics Data System (ADS)

Goh, K.-I.; Jeong, H.; Kahng, B.; Kim, D.

2000-08-01

We study the tilt dependence of the pinning-depinning transition for an interface described by the anisotropic quenched Kardar-Parisi-Zhang equation in 2+1 dimensions, where the two signs of the nonlinear terms are different from each other. When the substrate is tilted by m along the positive sign direction, the critical force Fc(m) depends on m as Fc(m)-Fc(0)~-\\|m\\|1.9(1). The interface velocity v near the critical force follows the scaling form v~\\|f\\|θΨ+/-(m2/\\|f\\|θ+φ) with θ=0.9(1) and φ=0.2(1), where f≡F-Fc(0) and F is the driving force.

Stress Response of Granular Systems

NASA Astrophysics Data System (ADS)

Ramola, Kabir; Chakraborty, Bulbul

2017-10-01

We develop a framework for stress response in two dimensional granular media, with and without friction, that respects vector force balance at the microscopic level. We introduce local gauge degrees of freedom that determine the response of contact forces between constituent grains on a given, disordered, contact network, to external perturbations. By mapping this response to the spectral properties of the graph Laplacian corresponding to the underlying contact network, we show that this naturally leads to spatial localization of forces. We present numerical evidence for localization using exact diagonalization studies of network Laplacians of soft disk packings. Finally, we discuss the role of other constraints, such as torque balance, in determining the stability of a granular packing to external perturbations.

La Observación Sistemática de Vecindarios: El caso de Chile y sus perspectivas para Trabajo Social

PubMed Central

Sanhueza, Guillermo E.; Delva, Jorge; Andrade, Fernando H.; Grogan-Kaylor, Andrew; Bares, Cristina; Castillo, Marcela

2012-01-01

El estudio acerca de las características de los vecindarios y sus efectos sobre las personas ha llegado a ser un área de creciente atención por parte de investigadores de diversas disciplinas en países desarrollados. Aunque actualmente existen diversas metodologías para estudiar efectos del vecindario, una de las más utilizadas es la Observación Sistemática de Vecindarios –Systematic Social Observation SSO, en inglés—porque permite recolectar información acerca de diversas características del entorno físico, social, ambiental y económico de los vecindarios donde se aplica. El objetivo de este artículo es (i) dar a conocer sumariamente algunas investigaciones influyentes sobre efectos del vecindario en Estados Unidos, ii) describir cómo se diseñó e implementó la Observación Sistemática de Vecindarios en la ciudad de Santiago de Chile, iii) señalar algunos facilitadores y obstaculizadores de la implementación del proyecto y, finalmente iv) enunciar posibles contribuciones y limitaciones que esta metodología ofrecería al trabajo social en Chile. PMID:24791060

The effects of capillary forces on the axisymmetric propagation of two-phase, constant-flux gravity currents in porous media

NASA Astrophysics Data System (ADS)

Golding, Madeleine J.; Huppert, Herbert E.; Neufeld, Jerome A.

2013-03-01

The effects of capillary forces on the propagation of two-phase, constant-flux gravity currents in a porous medium are studied analytically and numerically in an axisymmetric geometry. The fluid within a two-phase current generally only partially saturates the pore space it invades. For long, thin currents, the saturation distribution is set by the vertical balance between gravitational and capillary forces. The capillary pressure and relative permeability of the fluid in the current depend on this saturation. The action of capillary forces reduces the average saturation, thereby decreasing the relative permeability throughout the current. This results in a thicker current, which provides a steeper gradient to drive flow, and a more blunt-nose profile. The relative strength of gravity and capillary forces remains constant within a two-phase gravity current fed by a constant flux and spreading radially, due to mass conservation. For this reason, we use an axisymmetric representation of the framework developed by Golding et al. ["Two-phase gravity currents in porous media," J. Fluid Mech. 678, 248-270 (2011)], 10.1017/jfm.2011.110, to investigate the effect on propagation of varying the magnitude of capillary forces and the pore-size distribution. Scaling analysis indicates that axisymmetric two-phase gravity currents fed by a constant flux propagate like t1/2, similar to their single-phase counterparts [S. Lyle, H. E. Huppert, M. Hallworth, M. Bickle, and A. Chadwick, "Axisymmetric gravity currents in a porous medium," J. Fluid Mech. 543, 293-302 (2005)], 10.1017/S0022112005006713, with the effects of capillary forces encapsulated in the constant of proportionality. As a practical application of our new concepts and quantitative evaluations, we discuss the implications of our results for the process of carbon dioxide (CO2) sequestration, during which gravity currents consisting of supercritical CO2 propagate in rock saturated with aqueous brine. We apply our two-phase model including capillary forces to quantitatively assess seismic images of CO2 spreading at Sleipner underneath the North Sea.

Preparation and Microcosmic Structural Analysis of Recording Coating on Inkjet Printing Media

PubMed Central

Jiang, Bo; Liu, Weiyan; Bai, Yongping; Huang, Yudong; Liu, Li; Han, Jianping

2011-01-01

Preparation of recording coating on inkjet printing (RC-IJP) media was proposed. The microstructure and roughness of RC-IJP was analyzed by scanning electron microscopy (SEM) and atomic force microscope (AFM). The surface infiltration process of RC-IJP was studied by a liquid infiltration instrument. The distribution of C, O and Si composites on recording coating surface is analyzed by energy dispersive spectrum (EDS). The transmission electron microscopy (TEM) analysis showed that the nanoscale silica could be dissolved uniformly in water. Finally, the print color is shown clearly by the preparative recording coating. PMID:21954368

Kepler Media Briefing

NASA Image and Video Library

2009-02-19

William Borucki, principal investigator for Kepler Science at Ames Research Center, Moffett Field, Calif.,, second from left, talks about the Kepler mission during a media briefing, Thursday, Feb. 19, 2008, at NASA Headquarters in Washington. Kepler, the first mission with the ability to find planets like earth, is scheduled to launch on March 5, 2009 from Cape Canaveral Air Force Station, Fla. aboard a Delta II rocket. Joining Borucki at the briefing were Jon Morse, director, Astrophysics Division, NASA Headquarters, Jim Fanson, Kepler project manager at the Jet Propulsion Laboratory and Debra Fischer, a professor of Astronomy at San Francisco State University. Photo Credit: (NASA/Paul. E. Alers)

Orbital ATK CRS-7 Post Launch News Conference

NASA Image and Video Library

2017-04-18

Members of the news media attend a press conference at NASA's Kennedy Space Center in Florida, after the launch of the Orbital ATK Cygnus pressurized cargo module atop a United Launch Alliance Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station. It was Orbital ATK's seventh commercial resupply services mission to the International Space Station. Liftoff was at 11:11 a.m. EDT. Speaking to the media are, from left, George Diller, NASA Kennedy Communications; Joel Montalbano, deputy manager, International Space Station Program, NASA Johnson Space Center in Houston; and Frank Culbertson, president, Orbital ATK Space Systems Group.

A hierarchy of granular continuum models: Why flowing grains are both simple and complex

NASA Astrophysics Data System (ADS)

Kamrin, Ken

2017-06-01

Granular materials have a strange propensity to behave as either a complex media or a simple media depending on the precise question being asked. This review paper offers a summary of granular flow rheologies for well-developed or steady-state motion, and seeks to explain this dichotomy through the vast range of complexity intrinsic to these models. A key observation is that to achieve accuracy in predicting flow fields in general geometries, one requires a model that accounts for a number of subtleties, most notably a nonlocal effect to account for cooperativity in the flow as induced by the finite size of grains. On the other hand, forces and tractions that develop on macro-scale, submerged boundaries appear to be minimally affected by grain size and, barring very rapid motions, are well represented by simple rate-independent frictional plasticity models. A major simplification observed in experiments of granular intrusion, which we refer to as the `resistive force hypothesis' of granular Resistive Force Theory, can be shown to arise directly from rate-independent plasticity. Because such plasticity models have so few parameters, and the major rheological parameter is a dimensionless internal friction coefficient, some of these simplifications can be seen as consequences of scaling.

Lattice Boltzmann Simulation of Seismic Mobilization of Residual Oil in Sandstone

NASA Astrophysics Data System (ADS)

Guo, R.; Jiang, F.; Deng, W.

2017-12-01

Seismic stimulation is a promising technology for enhanced oil recovery. However, current mechanism studies are mainly in the single constricted tubes or idealized porous media, and no study has been conducted in real reservoir porous media. We have developed a numerical simulation which uses the lattice Boltzmann method to directly calculate the characteristics of residual oil clusters to quantify seismic mobilization of residual oil in real Berea sandstone in a scale of 400μm x 400μm x 400μm. The residual oil clusters will be firstly obtained by applying the water flooding scheme to the oil-saturated sandstone. Then, we will apply the seismic stimulation to the sandstone by converting the seismic effect to oscillatory inertial force and add to the pore fluids. This oscillatory inertial force causes the mobilization of residual oil by overcoming the capillary force. The response of water and oil to the seismic stimulation will be observed in our simulations. Two seismic oil mobilization mechanisms will be investigated: (1) the passive response of residual oil clusters to the seismic stimulation, and (2) the resonance of oil clusters subject to low frequency seismic stimulation. We will then discuss which mechanism should be the dominant mechanism for the seismic stimulation oil recovery for practical applications.

Numerical study on the hydrodynamic characteristics of biofouled full-scale net cage

NASA Astrophysics Data System (ADS)

Bi, Chun-wei; Zhao, Yun-peng; Dong, Guo-hai

2015-06-01

The effect of biofouling on the hydrodynamic characteristics of the net cage is of particular interest as biofouled nettings can significantly reduce flow of well-oxygenated water reaching the stocked fish. For computational efficiency, the porous-media fluid model is proposed to simulate flow through the biofouled plane net and full-scale net cage. The porous coefficients of the porous-media fluid model can be determined from the quadratic-function relationship between the hydrodynamic forces on a plane net and the flow velocity using the least squares method. In this study, drag forces on and flow fields around five plane nets with different levels of biofouling are calculated by use of the proposed model. The numerical results are compared with the experimental data of Swift et al. (2006) and the effectiveness of the numerical model is presented. On that basis, flow through full-scale net cages with the same level of biofouling as the tested plane nets are modeled. The flow fields inside and around biofouled net cages are analyzed and the drag force acting on a net cage is estimated by a control volume analysis method. According to the numerical results, empirical formulas of reduction in flow velocity and load on a net cage are derived as function of drag coefficient of the corresponding biofouled netting.

van der Waals torque and force between dielectrically anisotropic layered media.

PubMed

Lu, Bing-Sui; Podgornik, Rudolf

2016-07-28

We analyse van der Waals interactions between a pair of dielectrically anisotropic plane-layered media interacting across a dielectrically isotropic solvent medium. We develop a general formalism based on transfer matrices to investigate the van der Waals torque and force in the limit of weak birefringence and dielectric matching between the ordinary axes of the anisotropic layers and the solvent. We apply this formalism to study the following systems: (i) a pair of single anisotropic layers, (ii) a single anisotropic layer interacting with a multilayered slab consisting of alternating anisotropic and isotropic layers, and (iii) a pair of multilayered slabs each consisting of alternating anisotropic and isotropic layers, looking at the cases where the optic axes lie parallel and/or perpendicular to the plane of the layers. For the first case, the optic axes of the oppositely facing anisotropic layers of the two interacting slabs generally possess an angular mismatch, and within each multilayered slab the optic axes may either be the same or undergo constant angular increments across the anisotropic layers. In particular, we examine how the behaviors of the van der Waals torque and force can be "tuned" by adjusting the layer thicknesses, the relative angular increment within each slab, and the angular mismatch between the slabs.

Self-Cleaning Particulate Prefilter Media

NASA Technical Reports Server (NTRS)

Weber, Olivia; Lalwani, San-jiv; Sharma, Anjal

2012-01-01

A long-term space mission requires efficient air revitalization performance to sustain the crew. Prefilter and particulate air filter media are susceptible to rapid fouling that adversely affects their performance and can lead to catastrophic failure of the air revitalization system, which may result in mission failure. For a long-term voyage, it is impractical to carry replacement particulate prefilter and filter modules due to the usual limitations in size, volume, and weight. The only solution to this problem is to reagentlessly regenerate prefilter and filter media in place. A method was developed to modify the particulate prefilter media to allow them to regenerate reagentlessly, and in place, by the application of modest thermocycled transverse or reversed airflows. The innovation may allow NASA to close the breathing air loop more efficiently, thereby sustaining the vision for manned space exploration missions of the future. A novel, self-cleaning coatings technology was developed for air filter media surfaces that allows reagentless in-place regeneration of the surface. The technology grafts thermoresponsive and nonspecific adhesion minimizing polymer nanolayer brush coatings from the prefilter media. These polymer nanolayer brush architectures can be triggered to contract and expand to generate a "pushing-off" force by the simple application of modestly thermocycled (i.e. cycling from ambient cabin temperature to 40 C) air streams. The nonspecific adhesion-minimizing properties of the coatings do not allow the particulate foulants to adhere strongly to the filter media, and thermocycled air streams applied to the media allow easy detachment and in-place regeneration of the media with minimal impact in system downtime or astronaut involvement in overseeing the process.

Efectos combinados de la ampliación de la atención primaria de salud y de las transferencias condicionadas de dinero en efectivo sobre la mortalidad infantil en Brasil, 1998–2010*

PubMed Central

Guanais, Frederico C.

2015-01-01

Objetivos. Examiné los efectos combinados del acceso a la atención primaria mediante el Programa de Salud Familiar (PSF) y las transferencias condicionadas de dinero en efectivo del Programa Bolsa Familia (PBF) sobre la mortalidad infantil posneonatal (MIPN) en Brasil. Métodos. Empleé un análisis ecológico longitudinal usando datos en panel de 4 583 municipios brasileños de 1998 al 2010, con 54 253 observaciones en total. Estimé modelos de regresión de efectos fijos por mínimos cuadrados ordinarios, con la tasa de MIPN como la variable dependiente y el PSF, el PBF y sus interacciones como las principales variables independientes de interés. Resultados. La asociación de una mayor cobertura del PSF con una menor tasa de MIPN se volvió más fuerte conforme aumentaba la cobertura del PBF. En los promedios de todas las demás variables, cuando la cobertura de PBF era 25%, la MIPN predicha fue 5,24 (intervalo de confianza [IC] de 95% = 4,95, 5,53) para una cobertura del PSF de 0%, y de 3,54 (IC de 95% = 2,77, 4,31) para una cobertura del PSF de 100%. Cuando la cobertura del PBF era de 60%, la MIPN predicha fue 4,65 (IC de 95% = 4,36, 4,94) para una cobertura del PSF de 0%, y de 1,38 (IC de 95% = 0,88, 1,89) para una cobertura del PSF de 100%. Conclusiones. El efecto del PSF depende de la ampliación del PBF. Para las poblaciones empobrecidas y subatendidas, la combinación de intervenciones tanto del lado de la oferta como del lado de la demanda podría ser necesaria para mejorar los resultados en salud.

On the examination of Darcy permeability of soft fibrous porous media; New correlations

NASA Astrophysics Data System (ADS)

Zhu, Zenghao; Wang, Qiuyun; Wu, Qianhong

2017-11-01

In this presentation, we report a novel experimental approach to investigate the compression-dependent Darcy permeability of soft porous media. Especially, we are proposing new correlations that describe the change of the permeability of random fibrous porous media as a function of its compression. A special device was developed that consisted of a rectangular flow channel with adjustable gap thickness ranging from 3 mm to 20 mm. Air was forced through the thin gap filled with testing fibrous materials. By measuring the flow rate and the pressure gradient, we have successfully obtained the Darcy permeability of different fibrous porous materials at different compression ratios. Theoretical or semi-empirical models have been compared with the experimental results, indicating various degrees of disagreement. The new correlations were then proposed which fit with experimental data very well. The study presented herein provides a useful approach to evaluate the change of the permeability of fibrous porous media as a function of its compression. It will be valuable for examining fluid flow in fibrous porous media where the permeability is difficult to be measured directly. This kind of porous media widely exists in biological systems. This research was supported by the National Science Foundation under Award No. 1511096.

Less than Expected? How Media Cover Demonstration Turnout

PubMed Central

Wouters, Ruud; Van Camp, Kirsten

2017-01-01

Demonstration turnout is a crucial political resource for social movements. In this article, we investigate how mass media cover demonstration size. We develop a typology of turnout coverage and scrutinize the factors that drive turnout coverage. In addition, we test whether media coverage underestimates, reflects, or exaggerates “guesstimates” by organizers and police forces. Together, these analyses shed light on whether turnout coverage fits a logic of normalization or marginalization. We rely on a unique dataset of 428 demonstrations organized in Brussels (2003–2010). For these demonstrations, we have information on the turnout as reported in national television news, as counted by the police, and as expected by the organizers. We find that media present turnout most often as a fact, rarely as contentious (10 percent). Although few demonstrations pass the media gates, our study yields little to no evidence for a logic of turnout marginalization. Media coverage does not systematically underestimate demonstration size, nor does it blindly follow police counts. Rather, turnout coverage attests of a logic of normalization, following standard news-making practices. The more important the demonstration (size, lead item) and the larger the gap between police and organizer guesstimates, the more attention is paid to turnout in the news. Discussion centers on the generalizability and normative interpretation of the results. PMID:29081881

The History of Germany's Response to Climate Change.

ERIC Educational Resources Information Center

Cavender, Jeannine; Jager, Jill

1993-01-01

Traces the history of the German climate change debate in the last 50 years and discusses the forces and events that shaped it. Examines the way in which scientists, the government, industry, nongovernmental organizations, and the media entered into and influenced the debate. (54 references) (MDH)

Experimental measure of retinal impact force resulting from intraocular foreign body dropped onto retina through media of differing viscosity.

PubMed

Ernst, Benjamin J; Velez-Montoya, Raul; Kujundzic, Damir; Kujundzic, Elmira; Olson, Jeffrey L

2013-07-01

To evaluate and compare the perfluorocarbon liquid, silicone oil, and viscoelastic against standard saline, in their ability to dampen the impact force of a foreign body, dropped within the eye. In an experimental surgical model in where cohesive and adhesive forces of the substances are not enough to float heavy-than-water foreign bodies. A model of ophthalmic surgery was constructed. A BB pellet was dropped from 24 mm onto a force transducer through four different fluids: balanced salt solution, perfluoro-n-octane, viscoelastic, and silicone oil. The impact energy (force) for each case was measured and recorded by the force transducer. The mean force of impact for each fluid was compared using the Student t-test. Silicone oil resulted in the lowest force of impact. Both silicone oil and viscoelastic dampened the impact an order of magnitude more than perfluoro-n-octane and balanced salt solution. Silicone oil and viscoelastic cushioned the force from a dropped BB. They may be useful adjuncts to prevent iatrogenic retinal injury during vitrectomy for intraocular foreign body removal. © 2012 The Authors. Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.

You Can’t Win If You Don’t Play: Communication - Engage Early, Engage Often

DTIC Science & Technology

2014-02-01

the public but also, and more importantly, to the media. In one memorable case, Air Force broadcasters shot video of C-17s dropping food supplies...4. TITLE AND SUBTITLE You Can’t Win If You Don’t Play: Communication - Engage Early, Engage Often 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ...ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) Air Force

Understanding the Form, Function, and Logic of Clandestine Insurgent and Terrorist Networks: The First Step in Effective Counternetwork Operations

DTIC Science & Technology

2012-04-01

are examples of this external non- professional genre . These groups function much like the U.S. Army Special Forces conducting unconventional warfare...security force vehicle the IED was built to destroy, and conducts the operation. If he films the event, then he drops off the film at a drop-off point...and notifies the cell leader that the operation is complete. The cell leader directs the media cell to pick up the film from the drop-off site, and

Measured long-range repulsive Casimir–Lifshitz forces

PubMed Central

Munday, J. N.; Capasso, Federico; Parsegian, V. Adrian

2014-01-01

Quantum fluctuations create intermolecular forces that pervade macroscopic bodies1–3. At molecular separations of a few nanometres or less, these interactions are the familiar van der Waals forces4. However, as recognized in the theories of Casimir, Polder and Lifshitz5–7, at larger distances and between macroscopic condensed media they reveal retardation effects associated with the finite speed of light. Although these long-range forces exist within all matter, only attractive interactions have so far been measured between material bodies8–11. Here we show experimentally that, in accord with theoretical prediction12, the sign of the force can be changed from attractive to repulsive by suitable choice of interacting materials immersed in a fluid. The measured repulsive interaction is found to be weaker than the attractive. However, in both cases the magnitude of the force increases with decreasing surface separation. Repulsive Casimir–Lifshitz forces could allow quantum levitation of objects in a fluid and lead to a new class of switchable nanoscale devices with ultra-low static friction13–15. PMID:19129843

Analysis of Porous Media as Inlet Concept for Rotating Detonation Engines

NASA Astrophysics Data System (ADS)

Grogan, Kevin; Ihme, Matthias; Department of Mechanical Engineering Team

2016-11-01

Rotating detonation engines combust reactive gas mixtures with a high-speed, annularly-propagating detonation wave, which provides many advantages including a stagnation pressure gain and a compact, lightweight design. However, the optimal design of the inlet to the combustion chamber inlet is a moot topic since improper design can significantly reduce detonability and increase pressure losses. The highly diffusive properties of porous media could make it an ideal material to prevent the flashback of the detonation wave and therefore, allow the inlet gas to be premixed. Motivated by this potential, this work employs simulation to evaluate the application of porous media to the inlet of a rotating detonation engine as a novel means to stabilize a detonation wave while reducing the pressure losses incurred by non-ideal mixing strategies. Department of the Air Force.

Microfluidic devices, systems, and methods for quantifying particles using centrifugal force

DOEpatents

Schaff, Ulrich Y.; Sommer, Gregory J.; Singh, Anup K.

2015-11-17

Embodiments of the present invention are directed toward microfluidic systems, apparatus, and methods for measuring a quantity of cells in a fluid. Examples include a differential white blood cell measurement using a centrifugal microfluidic system. A method may include introducing a fluid sample containing a quantity of cells into a microfluidic channel defined in part by a substrate. The quantity of cells may be transported toward a detection region defined in part by the substrate, wherein the detection region contains a density media, and wherein the density media has a density lower than a density of the cells and higher than a density of the fluid sample. The substrate may be spun such that at least a portion of the quantity of cells are transported through the density media. Signals may be detected from label moieties affixed to the cells.

Paint removal activities in Canada

NASA Astrophysics Data System (ADS)

Foster, Terry

1993-03-01

Paint removal activities currently under way in Canada include: research and development of laser paint stripping; development and commercialization of a new blasting medium based on wheat starch; commercialization of a new blasting medium and process using crystalline ice blasting for paint removal and surface cleaning; and the development of automated and robotic systems for paint stripping applications. A specification for plastic media blasting (PMB) of aircraft and aircraft components is currently being drafted by NDHQ for use by the Canadian Armed Forces (CAF) and contractors involved in coating removal for the CAF. Defense Research Establishment Pacific (DREP) is studying the effects of various blast media on coating removal rates, and minimizing the possibility of damage to substrates other than aluminum such as graphite epoxy composite and Kevlar. The effects of plastic media blasting on liquid penetrant detection of fatigue cracks is also under investigation.

Microgravity and Hypogravity Compatible Methods for the Destruction of Solid Wastes by Magnetically Assisted Gasification

NASA Technical Reports Server (NTRS)

Atwater, James E.; Akse, James R.; Wheeler, Richard R., Jr.; Jovanovic, Goran N.; Pinto-Espinoza, Joaquin; Reed, Brian; Sornchamni, Thana

2003-01-01

This report summarizes a three-year collaborative effort between researchers at UMPQUA Research Company (URC) and the Chemical Engineering Department at Oregon State University (OSU). The Magnetically Assisted Gasification (MAG) concept was originally conceived as a microgravity and hypogravity compatible means for the decomposition of solid waste materials generated aboard spacecraft, lunar and planetary habitations, and for the recovery of potentially valuable resources. While a number of methods such as supercritical water oxidation (SCW0), fluidized bed incineration, pyrolysis , composting and related biological processes have been demonstrated for the decomposition of solid wastes, none of these methods are particularly well- suited for employment under microgravity or hypogravity conditions. For example, fluidized bed incineration relies upon a balance between drag forces which the flowing gas stream exerts upon the fluidization particles and the opposing force of gravity. In the absence of gravity, conventional fluidization cannot take place. Hypogravity operation can also be problematic for conventional fluidized bed reactors, because the various factors which govern fluidization phenomena do not all scale linearly with gravity. For this reason it may be difficult to design and test fluidized bed reactors in lg, which are intended to operate under different gravitational conditions. However, fluidization can be achieved in microgravity (and hypogravity) if a suitable replacement force to counteract the forces between fluid and particles can be found. Possible alternatives include: centripetal force, electric fields, or magnetic fields. Of these, magnetic forces created by the action of magnetic fields and magnetic field gradients upon ferromagnetic media offer the most practical approach. The goal of this URC-OSU collaborative effort was to develop magnetic hardware and methods to control the degree of fluidization (or conversely consolidation) of granular ferromagnetic media and to employ these innovations in sequential filtration and fluidized bed processes for the segregation and decomposition of solid waste materials, and for the concentration and collection of inorganic residue (ash). This required the development of numerous enabling technologies and tools.

Uniform circular motion concept attainment through circle share learning model using real media

NASA Astrophysics Data System (ADS)

Ponimin; Suparmi; Sarwanto; Sunarno, W.

2017-01-01

Uniform circular motion is an important concept and has many applications in life. Student’s concept understanding of uniform circular motion is not optimal because the teaching learning is not carried out properly in accordance with the characteristics of the concept. To improve student learning outcomes required better teaching learning which is match with the characteristics of uniform circular motion. The purpose of the study is to determine the effect of real media and circle share model to the understanding of the uniform circular motion concept. The real media was used to visualize of uniform circular motion concept. The real media consists of toy car, round table and spring balance. Circle share model is a learning model through discussion sequentially and programmed. Each group must evaluate the worksheets of another group in a circular position. The first group evaluates worksheets the second group, the second group evaluates worksheets third group, and the end group evaluates the worksheets of the first group. Assessment of learning outcomes includes experiment worksheets and post-test of students. Based on data analysis we obtained some findings. First, students can explain the understanding of uniform circular motion whose angular velocity and speed is constant correctly. Second, students can distinguish the angular velocity and linear velocity correctly. Third, students can explain the direction of the linear velocity vector and the direction of the centripetal force vector. Fourth, the student can explain the influence of the mass, radius, and velocity toward the centripetal force. Fifth, students can explain the principle of combined of wheels. Sixth, teaching learning used circle share, can increase student activity, experimental results and efficiency of discussion time.

Water movement in glass bead porous media: 1. Experiments of capillary rise and hysteresis

NASA Astrophysics Data System (ADS)

Lu, T. X.; Biggar, J. W.; Nielsen, D. R.

1994-12-01

Experimental observations of capillary rise and hysteresis of water or ethanol in glass beads are presented to improve our understanding of those physical processes in porous media. The results provide evidence that capillary rise into porous media cannot be fully explained by a model of cylinders. They further demonstrate that the "Ink bottle" model does not provide an adequate explanation of hysteresis. Glass beads serving as a model for ideal soil are enclosed in a rectangular glass chamber model. A TV camera associated with a microscope was used to record the processes of capillary rise and drainage. It is clearly shown during capillary rise that the fluid exhibits a "jump" behavior at the neck of the pores in an initially dry profile or at the bottom of the water film in an initially wet profile. Under an initially dry condition, the jump initiates at the particle with smallest diameter. The jump process continues to higher elevations until at equilibrium the surface tensile force is balanced by the hydrostatic force. The wetting front at that time is readily observed as flat and saturated. Under an initially wet condition, capillary rise occurs as a water film thickening process associated with the jump process. Trapped air behind the wetting front renders the wetting front irregular and unsaturated. The capillary rise into an initially wet porous medium can be higher than that into an initially dry profile. During the drying process, large surface areas associated with the gas-liquid interface develop, allowing the porous medium to retain more water than during the wetting process at the same pressure. That mechanism explains better the hysteresis phenomenon in porous media in contrast to other mechanisms that now prevail.

Who Teaches Mathematics at Second Level in Ireland?

ERIC Educational Resources Information Center

Ni Riordain, Maire; Hannigan, Ailish

2011-01-01

Ireland's "mathematics problem" is well-documented and extensively reported in the media and elsewhere (Expert Group on Future Skills Needs (EGFSN) 2008; Task Force on the Physical Sciences 2002). Concern primarily lies with post-primary students' underperformance in mathematics coupled with a failure to make a successful transition to…

Violence against Teachers: Case Studies from the APA Task Force

ERIC Educational Resources Information Center

Reddy, Linda A.; Espelage, Dorothy; McMahon, Susan D.; Anderman, Eric M.; Lane, Kathleen Lynne; Brown, Veda Evanell; Reynolds, Cecil R.; Jones, Abraham; Kanrich, Jaclyn

2013-01-01

Violence directed toward teachers has been understudied despite significant media and empirical investigation on school violence, such as student-to-student victimization and bullying. To date, there are relatively few published studies scattered across many countries. To address this void, the American Psychological Association, in collaboration…

Extended abstract on the potential for Phytophthora ramorum to infest finished compost

Treesearch

Steven Swain; Matteo Garbelotto

2006-01-01

The survival rate of Phytophthora ramorum was assessed when introduced at high rates into composts of varying provenance and curing time, produced by both "turned windrow" and "forced air static pile" techniques. Survival in some compost media was high and statistically indistinguishable from positive controls (P

KSC-2015-1014

NASA Image and Video Library

2015-01-05

In the Kennedy Space Center’s Press Site auditorium, agency and industry leaders spoke to members of the news media on International Space Station research and technology developments. Participants included Maj. Perry Sweat, U.S. Air Force’s 45th Weather Squadron at Cape Canaveral Air Force Station. Photo credit: NASA/Kim Shiflett

Digital Literacy: Tools and Methodologies for Information Society

ERIC Educational Resources Information Center

Rivoltella, Pier Cesare, Ed.

2008-01-01

Currently in a state of cultural transition, global society is moving from a literary society to digital one, adopting widespread use of advanced technologies such as the Internet and mobile devices. Digital media has an extraordinary impact on society's formative processes, forcing a pragmatic shift in their management and organization. This…

Rhizomatic Explorations in Curriculum

ERIC Educational Resources Information Center

Smitka, Julie A. M.

2012-01-01

A visual and theatrical exercise anchored in the Grades 11 and 12 Ontario Curriculum for Media Arts and Interdisciplinary Studies was enacted and recorded as individual experiences of each participant. The event was re-mastered in a graphic representation that depicts the forces, pushes and pulls of curriculum and students' needs which educators…

A visualization study on two-phase gravity drainage in porous media by using magnetic resonance imaging.

PubMed

Teng, Ying; Liu, Yu; Jiang, Lanlan; Song, Yongchen; Zhao, Jiafei; Zhang, Yi; Wang, Dayong

2016-09-01

Gravity drainage characteristics are important to improve our understanding of gas-liquid or liquid-liquid two-phase flow in porous media. Stable or unstable displacement fronts that controlled by the capillary force, viscous force, gravitational force, etc., are relevant features of immiscible two-phase flow. In this paper, three dimensionless parameters, namely, the gravity number, the capillary number and the Bond number, were used to describe the effect of the above mentioned forces on two-phase drainage features, including the displacement front and final displacing-phase saturation. A series of experiments on the downward displacement of a viscous fluid by a less viscous fluid in a vertical vessel that is filled with quartz beads are performed by using magnetic resonance imaging (MRI). The experimental results indicate that the wetting properties at both high and low capillary numbers exert remarkable control on the fluid displacement. When the contact angle is lower than 90°, i.e., the displaced phase is the wetting phase, the average velocity Vf of the interface of the two phases (displacement front velocity) is observably lower than when the displaced phase is the non-wetting phase (contact angle higher than 90°). The results show that a fingering phenomenon occurs when the gravity number G is less than the critical gravity number G'=Δμ/μg. Moreover, the higher Bond number results in higher final displacing-phase saturation, whereas the capillary number has an opposite effect. Copyright © 2016 Elsevier Inc. All rights reserved.

Performance evaluation of ALCAN-AASF50-ferric coated activated alumina and granular ferric hydroxide (GFH) for arsenic removal in the presence of competitive ions in an active well :Kirtland field trial - initial studies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neidel, Linnah L.; Krumhansl, James Lee; Siegel, Malcolm Dean

This report documents a field trial program carried out at Well No.15 located at Kirtland Air Force Base, Albuquerque, New Mexico, to evaluate the performance of two relatively new arsenic removal media, ALCAN-AASF50 (ferric coated activated alumina) and granular ferric hydroxide (US Filter-GFH). The field trial program showed that both media were able to remove arsenate and meet the new total arsenic maximum contaminant level (MCL) in drinking water of 10 {micro}g/L. The arsenate removal capacity was defined at a breakthrough effluent concentration of 5 {micro}g/L arsenic (50% of the arsenic MCL of 10 {micro}g/L). At an influent pH ofmore » 8.1 {+-} 0.4, the arsenate removal capacity of AASF50 was 33.5 mg As(V)/L of dry media (29.9 {micro}g As(V)/g of media on a dry basis). At an influent pH of 7.2 {+-} 0.3, the arsenate removal capacity of GFH was 155 mg As(V)/L of wet media (286 {micro}g As(V)/g of media on a dry basis). Silicate, fluoride, and bicarbonate ions are removed by ALCAN AASF50. Chloride, nitrate, and sulfate ions were not removed by AASF50. The GFH media also removed silicate and bicarbonate ions; however, it did not remove fluoride, chloride, nitrate, and sulfate ions. Differences in the media performance partly reflect the variations in the feed-water pH between the 2 tests. Both the exhausted AASF50 and GFH media passed the Toxicity Characteristic Leaching Procedure (TCLP) test with respect to arsenic and therefore could be disposed as nonhazardous waste.« less

Social Media in Pediatric Orthopaedics.

PubMed

Lander, Sarah T; Sanders, James O; Cook, Peter C; O'Malley, Natasha T

Internet searches and social media utilization in health care has exploded over the past 5 years, and patients utilize it to gain information on their health conditions and physicians. Social media has the potential to serve as a means for education, communication, and marketing in all health care specialties. Physicians are sometimes reluctant to engage because of concerns of privacy, litigation, and lack of experience with this modality. Many surgical subspecialties have capitalized on social media but no study to date has examined the specific footprint of pediatric orthopaedic surgeons in this realm. We aim to quantify the utilization of individual social media platforms by pediatric orthopaedic surgeons, and identify any differences between private and hospital-based physicians, but also regional differences. Using the Pediatric Orthopaedic Society of North America Member Directory, each active member's social media presence was reviewed through an Internet search. Members were stratified on the basis of practice model and geographic location. Individual Internet searches, social media sites, and number of publications were reviewed for social media presence. Of 987 Pediatric Orthopaedic Society of North America members, 95% had a professional webpage, 14.8% a professional Facebook page, 2.2% a professional Twitter page, 36.8% a LinkedIn profile, 25.8% a ResearchGate profile, 33% at least 1 YouTube. Hospital-based physicians had a lower mean level of utilization of social media compared with their private practice peers, and a higher incidence of Pubmed publications. Private practice physicians had double the social media utilization. Regional differences reveal that practicing Pediatric Orthopaedists in the Northeast had increased utilization of ResearchGate and LinkedIn and the West had the lowest mean social media utilization levels. The rapid expansion of social media usage by patients and their family members is an undeniable force affecting the health care industry. The Internet and social media platforms provide all physicians with a means to educate patients, collaborate with colleagues, and promote their practice and areas of interest. Our survey indicates that pediatric orthopaedic surgeons may be underutilizing their potential social media presence. Level IV.

Porous media grain size distribution and hydrodynamic forces effects on transport and deposition of suspended particles.

PubMed

Ahfir, Nasre-Dine; Hammadi, Ahmed; Alem, Abdellah; Wang, HuaQing; Le Bras, Gilbert; Ouahbi, Tariq

2017-03-01

The effects of porous media grain size distribution on the transport and deposition of polydisperse suspended particles under different flow velocities were investigated. Selected Kaolinite particles (2-30μm) and Fluorescein (dissolved tracer) were injected in the porous media by step input injection technique. Three sands filled columns were used: Fine sand, Coarse sand, and a third sand (Mixture) obtained by mixing the two last sands in equal weight proportion. The porous media performance on the particle removal was evaluated by analysing particles breakthrough curves, hydro-dispersive parameters determined using the analytical solution of convection-dispersion equation with a first order deposition kinetics, particles deposition profiles, and particle-size distribution of the recovered and the deposited particles. The deposition kinetics and the longitudinal hydrodynamic dispersion coefficients are controlled by the porous media grain size distribution. Mixture sand is more dispersive than Fine and Coarse sands. More the uniformity coefficient of the porous medium is large, higher is the filtration efficiency. At low velocities, porous media capture all sizes of suspended particles injected with larger ones mainly captured at the entrance. A high flow velocity carries the particles deeper into the porous media, producing more gradual changes in the deposition profile. The median diameter of the deposited particles at different depth increases with flow velocity. The large grain size distribution leads to build narrow pores enhancing the deposition of the particles by straining. Copyright © 2016. Published by Elsevier B.V.

TDRS-M NASA Social

NASA Image and Video Library

2017-08-17

Emily Furfaro of the NASA Social Media Team speaks to members of social media in the Kennedy Space Center’s Press Site auditorium. The briefing focused on preparations to launch NASA's Tracking and Data Relay Satellite, TDRS-M. The latest spacecraft destined for the agency's constellation of communications satellites, TDRS-M will allow nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop a United Launch Alliance Atlas V rocket is scheduled to take place from Space Launch Complex 41 at Cape Canaveral Air Force Station at 8:03 a.m. EDT Aug. 18.

TDRS-M NASA Social

NASA Image and Video Library

2017-08-17

Amber Jacobson of the NASA TDRS Social Media Team speaks to members of social media in the Kennedy Space Center’s Press Site auditorium. The briefing focused on preparations to launch NASA's Tracking and Data Relay Satellite, TDRS-M. The latest spacecraft destined for the agency's constellation of communications satellites, TDRS-M will allow nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop a United Launch Alliance Atlas V rocket is scheduled to take place from Space Launch Complex 41 at Cape Canaveral Air Force Station at 8:03 a.m. EDT Aug. 18.

Frontogenesis driven by horizontally quadratic distributions of density

NASA Technical Reports Server (NTRS)

Jacqmin, David

1991-01-01

Attention is given to the quadratic density distribution in a channel, which has been established by Simpson and Linden to be the simplest case of the horizontally nonlinear distribution of fluid density required for the production of frontogenesis. The porous-media and Boussinesq flow models are examined, and their evolution equations are reduced to one-dimensional systems. While both the porous-media and the inviscid/nondiffusive Boussinesq systems exhibit classic frontogenesis behavior, the viscous Boussinesq system exhibits a more complex behavior: boundary-layer effects force frontogenesis away from the lower boundary, and at late times the steepest density gradients are close to mid-channel.

Stress Transmission in Granular Packings: Localization and Cooperative Response

NASA Astrophysics Data System (ADS)

Ramola, Kabir

We develop a framework for stress transmission in two dimensional granular media that respects vector force balance at the microscopic level. For a packing of grains interacting via pairwise contact forces, we introduce local gauge degrees of freedom that determine the response of the system to external perturbations. This allows us to construct unique force-balanced solutions that determine the change in contact forces as a response to external stress. By mapping this response to diffusion in the underlying contact network, we show that this naturally leads to spatial localization of forces. We present numerical evidence for stress localization using exact diagonalization studies of network Laplacians associated with soft disk packings. We use this formalism to characterize the deviation from elastic behaviour as the amount of disorder in the underlying network is varied. We discuss generalizations to systems with large friction between grains and other networks that display topological disorder. This work has been supported by NSF-DMR 1409093 and the W. M. Keck Foundation.

Information driving force and its application in agent-based modeling

NASA Astrophysics Data System (ADS)

Chen, Ting-Ting; Zheng, Bo; Li, Yan; Jiang, Xiong-Fei

2018-04-01

Exploring the scientific impact of online big-data has attracted much attention of researchers from different fields in recent years. Complex financial systems are typical open systems profoundly influenced by the external information. Based on the large-scale data in the public media and stock markets, we first define an information driving force, and analyze how it affects the complex financial system. The information driving force is observed to be asymmetric in the bull and bear market states. As an application, we then propose an agent-based model driven by the information driving force. Especially, all the key parameters are determined from the empirical analysis rather than from statistical fitting of the simulation results. With our model, both the stationary properties and non-stationary dynamic behaviors are simulated. Considering the mean-field effect of the external information, we also propose a few-body model to simulate the financial market in the laboratory.

Modelling of deformation process for the layer of elastoviscoplastic media under surface action of periodic force of arbitrary type

NASA Astrophysics Data System (ADS)

Mikheyev, V. V.; Saveliev, S. V.

2018-01-01

Description of deflected mode for different types of materials under action of external force plays special role for wide variety of applications - from construction mechanics to circuits engineering. This article con-siders the problem of plastic deformation of the layer of elastoviscolastic soil under surface periodic force. The problem was solved with use of the modified lumped parameters approach which takes into account close to real distribution of normal stress in the depth of the layer along with changes in local mechanical properties of the material taking place during plastic deformation. Special numeric algorithm was worked out for computer modeling of the process. As an example of application suggested algorithm was realized for the deformation of the layer of elasoviscoplastic material by the source of external lateral force with the parameters of real technological process of soil compaction.

Finite-volume method with lattice Boltzmann flux scheme for incompressible porous media flow at the representative-elementary-volume scale.

PubMed

Hu, Yang; Li, Decai; Shu, Shi; Niu, Xiaodong

2016-02-01

Based on the Darcy-Brinkman-Forchheimer equation, a finite-volume computational model with lattice Boltzmann flux scheme is proposed for incompressible porous media flow in this paper. The fluxes across the cell interface are calculated by reconstructing the local solution of the generalized lattice Boltzmann equation for porous media flow. The time-scaled midpoint integration rule is adopted to discretize the governing equation, which makes the time step become limited by the Courant-Friedricks-Lewy condition. The force term which evaluates the effect of the porous medium is added to the discretized governing equation directly. The numerical simulations of the steady Poiseuille flow, the unsteady Womersley flow, the circular Couette flow, and the lid-driven flow are carried out to verify the present computational model. The obtained results show good agreement with the analytical, finite-difference, and/or previously published solutions.

Democracy to Come: Active Forums as Indicator Suites for e-Participation and e-Governance

NASA Astrophysics Data System (ADS)

Rodan, Debbie; Balnaves, Mark

There is in modern industrial societies a ‘civic deficit’ Civic engagement in the traditional sense of community values and civic participation is declining (Putman 2000). What has not been examined is the ways in which various media including new media may provide real options for participatory cultures and participatory democracy now and in the future. Undoubtedly there are differences between participatory cultures that are considered a ‘genuine’ contribution to representational democracy and those that are not. This paper, based on initial research into Internet activism, will examine GetUp! as a specific example of an active forum that the authors argue enable participatory citizenship through media participation. While there are very few examples of active forums that might be considered a ‘genuine’ contribution to representational democracy there are clear signals that activism through active forums is maturing into a potent democratic force.

Media Representation of Tongxinglian in China: A Case Study of the People's Daily.

PubMed

Huang, Yixiong

2018-01-01

Over the past few decades, the worldwide lesbian and gay movements have diversified and increased their rights claims. The achievement of gay rights claims in society is the result of an interplay among various social factors and forces. Media is one of most influential players in building homosexual images and promoting mutual understanding. Chinese homosexuals were not treated as criminals or mental illness patients anymore in 1997 and 2001, respectively, after decriminalization and depathologization. Thus this article aims to explore how homosexuals were portrayed in the official media of China, particularly the People's Daily, to illustrate the changing perception of homosexuals in China's political and social spheres. It argues that representation of homosexuals in the People's Daily changed gradually from a negative perception to a more positive one with less discrimination and prejudice as shown by the article's quantitative and qualitative results.

Short-pulse laser interactions with disordered materials and liquids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phinney, L.M.; Goldman, C.H.; Longtin, J.P.

High-power, short-pulse lasers in the picosecond and subpicosecond range are utilized in an increasing number of technologies, including materials processing and diagnostics, micro-electronics and devices, and medicine. In these applications, the short-pulse radiation interacts with a wide range of media encompassing disordered materials and liquids. Examples of disordered materials include porous media, polymers, organic tissues, and amorphous forms of silicon, silicon nitride, and silicon dioxide. In order to accurately model, efficiently control, and optimize short-pulse, laser-material interactions, a thorough understanding of the energy transport mechanisms is necessary. Thus, fractals and percolation theory are used to analyze the anomalous diffusion regimemore » in random media. In liquids, the thermal aspects of saturable and multiphoton absorption are examined. Finally, a novel application of short-pulse laser radiation to reduce surface adhesion forces in microstructures through short-pulse laser-induced water desorption is presented.« less

Community violence, children's development, and mass media: in pursuit of new insights, new goals, and new strategies.

PubMed

Friedlander, B Z

1993-02-01

Community violence that victimizes children is an unmitigated evil that is exacerbated by vast economic and social forces that leave people in central cities and the rural countryside adrift on seas of rolelessness, hopelessness, group disintegration, and alienation. The contemporary drug scene and the easy availability of guns greatly intensify violence on a local scale, while crimes of violence, especially with guns, appear to be level or declining in the nation as a whole. Claims that the persistently high levels of violence in mass media, mostly television, are largely responsible for violence in society represent narrow views of very large issues. These narrow views overlook essential elements of both phenomena--violence and media. Direct models of interpersonal violence in families and in the community probably give rise to more violent behavior than indirect models in media. Disinhibitory and provocative aspects of media probably do as much or more to trigger violent behavior than violent narratives and violent actions. Comprehensive meta-analysis indicates that prosocial messages on television can have greater effects on behavior than antisocial messages. These data support the contention that mass media can play a strong and positive role in alleviating some of the distress of victims of community violence, and in redirecting the behavior of some of its perpetrators so as to protect the children.

3D finite element modelling of force transmission and particle fracture of sand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Imseeh, Wadi H.; Alshibli, Khalid A.

Global compressive loading of granular media causes rearrangements of particles into a denser configuration. Under 1D compression, researchers observed that particles initially translate and rotate which lead to more contacts between particles and the development of force chains to resist applied loads. Particles within force chains resist most of the applied loads while neighbor particles provide lateral support to prevent particles within force chains from buckling. Several experimental and numerical models have been proposed in the literature to characterize force chains within granular materials. This paper presents a 3D finite element (FE) model that simulates 1D compression experiment on F-75more » Ottawa sand. The FE mesh of particles closely matched 3D physical shape of sand particles that were acquired using 3D synchrotron micro-computed tomography (SMT) technique. The paper presents a quantitative assessment of the model, in which evolution of force chains, fracture modes, and stress-strain relationships showed an excellent agreement with experimental measurements reported by Cil et al. Alshibli (2017).« less

Effects of aperture variability and wettability on immiscible displacement in fractures

NASA Astrophysics Data System (ADS)

Yang, Zhibing; Méheust, Yves; Neuweiler, Insa

2017-04-01

Fluid-fluid displacement in porous and fractured media is an important process. Understanding and controlling this process is key to many practical applications, such as hydrocarbon recovery, geological storage of CO2, groundwater remediation, etc. Here, we numerically study fluid-fluid displacement in rough-walled fractures. We focus on the combined effect of wettability and fracture surface topography on displacement patterns and interface growth. We develop a novel numerical model to simulate dynamic fluid invasion under the influence of capillary and viscous forces. The capillary force is calculated using the two principal curvatures (aperture-induced curvature and in-plane curvature) at the fluid-fluid interface, and the viscous force is taken into account by solving the fluid pressure distribution. The aperture field of a fracture is represented by a spatially correlated random field, which is described by a power spectrum for the fracture wall topography and a cutoff wave-length. We numerically produce displacement patterns ranging from stable displacement, capillary fingering, and viscous fingering, as well as the transitions between them. We show that both reducing the aperture variability and increasing the contact angle (from drainage to weak imbibition) stabilize the displacement due to the influence of the in-plane curvature, an effect analogous to that of the cooperative pore filling in porous media. Implications of these results will be discussed.

KSC-06pd1279

NASA Image and Video Library

2006-06-28

KENNEDY SPACE CENTER, FLA. - Under the watchful eyes of the media, an upper-level weather balloon begins its lift into the sky. The release of the balloon at the Cape Canaveral weather station in Florida was part of a media tour prior to the launch of Space Shuttle Discovery on mission STS-121 July 1. The radar-tracked balloon detects wind shears that can affect a shuttle launch. At the facility, which is operated by the U.S. Air Force 45th Weather Squadron, media saw the tools used by the weather team to create the forecast for launch day. They received a briefing on how the launch weather forecast is developed by Shuttle Weather Officer Kathy Winters and met the forecasters for the space shuttle and the expendable launch vehicles. Also participating were members of the Applied Meteorology Unit who provide special expertise to the forecasters by analyzing and interpreting unusual or inconsistent weather data. The media were able to see the release of the Rawinsonde weather balloon carrying instruments aloft to be used as part of developing the forecast. Photo credit: NASA/George Shelton

Spontaneous and Directional Bubble Transport on Porous Copper Wires with Complex Shapes in Aqueous Media.

PubMed

Li, Wenjing; Zhang, Jingjing; Xue, Zhongxin; Wang, Jingming; Jiang, Lei

2018-01-24

Manipulation of gas bubble behaviors is crucial for gas bubble-related applications. Generally, the manipulation of gas bubble behaviors generally takes advantage of their buoyancy force. It is very difficult to control the transportation of gas bubbles in a specific direction. Several approaches have been developed to collect and transport bubbles in aqueous media; however, most reliable and effective manipulation of gas bubbles in aqueous media occurs on the interfaces with simple shapes (i.e., cylinder and cone shapes). Reliable strategies for spontaneous and directional transport of gas bubbles on interfaces with complex shapes remain enormously challenging. Herein, a type of 3D gradient porous network was constructed on copper wire interfaces, with rectangle, wave, and helix shapes. The superhydrophobic copper wires were immersed in water, and continuous and stable gas films then formed on the interfaces. With the assistance of the Laplace pressure gradient between two bubbles, gas bubbles (including microscopic gas bubbles) in the aqueous media were subsequently transported, continuously and directionally, on the copper wires with complex shapes. The small gas bubbles always moved to the larger ones.

Power structure in Chilean news media

PubMed Central

Bahamonde, Jorge; Bollen, Johan; Ferres, Leo; Poblete, Barbara

2018-01-01

Even democracies endowed with the most active free press struggle to maintain diversity of news coverage. Consolidation and market forces may cause only a few dominant players to control the news cycle. Editorial policies may be biased by corporate ownership relations, narrowing news coverage and focus. To an increasing degree this problem also applies to social media news distribution, since it is subject to the same socio-economic drivers. To study the effects of consolidation and ownership on news diversity, we model the diversity of Chilean coverage on the basis of ownership records and social media data. We create similarity networks of news outlets on the basis of their ownership and the topics they cover. We then examine the relationships between the topology of ownership networks and content similarity to characterize how ownership affects news coverage. A network analysis reveals that Chilean media is highly concentrated both in terms of ownership as well as in terms of topics covered. Our method can be used to determine which groups of outlets and ownership exert the greatest influence on news coverage. PMID:29874241

Power structure in Chilean news media.

PubMed

Bahamonde, Jorge; Bollen, Johan; Elejalde, Erick; Ferres, Leo; Poblete, Barbara

2018-01-01

Even democracies endowed with the most active free press struggle to maintain diversity of news coverage. Consolidation and market forces may cause only a few dominant players to control the news cycle. Editorial policies may be biased by corporate ownership relations, narrowing news coverage and focus. To an increasing degree this problem also applies to social media news distribution, since it is subject to the same socio-economic drivers. To study the effects of consolidation and ownership on news diversity, we model the diversity of Chilean coverage on the basis of ownership records and social media data. We create similarity networks of news outlets on the basis of their ownership and the topics they cover. We then examine the relationships between the topology of ownership networks and content similarity to characterize how ownership affects news coverage. A network analysis reveals that Chilean media is highly concentrated both in terms of ownership as well as in terms of topics covered. Our method can be used to determine which groups of outlets and ownership exert the greatest influence on news coverage.

Media coverage of anthrax vaccination refusal by Australian Defence Force personnel.

PubMed

Ackermann, Deonna; Chapman, Simon; Leask, Julie

2004-12-02

During February 2003 a number of Australian sailors were returned home from their deployment to the Persian Gulf after refusing anthrax vaccination. This paper examines the media coverage of this episode as a case study in how controversies about vaccine safety escalate. Frame analysis of articles from major Australian newspapers (n=83) and transcripts of radio and television news and current affairs programs (n=22) to identify the main supportive and oppositional themes used in reportage and media debate. Initially, the major news frames were supportive of the vaccine refusing soldiers, and conveyed a sense of distrust of the government's actions. These initial themes were rapidly re-framed and new dominant discourses appeared. First, sailors went from brave whistleblowers to being portrayed as deserters and cowards. Second, proponents shifted from their portrayal as faceless regulators to personal risk takers embodied in a well-respected Major General having the vaccine. Third, the voluntary nature of the vaccine was emphasised, thus dousing the flames of implied coercion. Marked shifts in the representation of vaccine opponents and proponents possibly contributed to the rapid diminishment of media interest in the story.

Influence of E-Learning on Sales Productivity

ERIC Educational Resources Information Center

Livingston, David T.

2012-01-01

For companies to stay competitive, they must continually bring new products and services to the marketplace. One strategy organizations can use to support this requirement is to provide their sales force with training that enables revenue generation. The types of instructional methods and media used to deploy the training can have an impact on the…

Joint Chiefs of Staff > Media > Publications

Science.gov Websites

Facebook on Flickr Joint Chiefs Army Chief of Staff Marine Corps Commandant Chief of Naval Operations Air Force Chief of Staff Chief of National Guard Bureau Biographies Directorates Directorates of Management - Upholding Our Oath SEAC's Publications Book | The Noncommissioned Officer and Petty Officer SEAC's Articles

Transnational Migration, Social Capital and Lifelong Learning in the USA

ERIC Educational Resources Information Center

Alfred, Mary V.

2010-01-01

At the beginning of the twenty-first century, immigration continues to be a powerful force that shapes the US demographic landscape and hence influences all aspects of US lifeways. Unlike past waves of immigration, communication, media and transportation technologies enable today's immigrants to maintain strong ties and relationships with their…

The International Marketplace for Television Programming: New Strategies for the 1980s.

ERIC Educational Resources Information Center

Renaud, Jean-Luc; Litman, Barry R.

The growing importance of the export market for the United States television industry--specifically, the structure of the syndication industry, and the strategies developed by U.S. producers and syndicators as a response to the new economic imperatives and the disciplining force of the international media environment on programing decisions--was…

Preparation of asymmetric porous materials

DOEpatents

Coker, Eric N [Albuquerque, NM

2012-08-07

A method for preparing an asymmetric porous material by depositing a porous material film on a flexible substrate, and applying an anisotropic stress to the porous media on the flexible substrate, where the anisotropic stress results from a stress such as an applied mechanical force, a thermal gradient, and an applied voltage, to form an asymmetric porous material.

The Secret Driving Force Behind Mongolia’s Successful Democracy

DTIC Science & Technology

2016-03-01

and media representatives from Myanmar dur- ing a recent visit to Mongolia, I was asked many questions regarding issues that we take for granted. As...the head of the Mongolian- Myanmar parliamentary group, I extended my best wishes to the Myanmar people’s effort to reform their country into a

About the Joint Chiefs of Staff

Science.gov Websites

JCS: Search Home Media News Photos Videos Publications About The Joint Staff Chairman Vice Chairman J8 | Force Structure, Resources & Assessment Contact Joint Staff Structure Home : About About the Joint Chiefs of Staff Download the CJCS Historic Guide The Joint Chiefs of Staff consist of the Chairman

Emerging Trilingual Literacies in Rural India: Linguistic, Marketing, and Developmental Aspects

ERIC Educational Resources Information Center

Bhatia, Tej K.; Ritchie, William C.

2016-01-01

This paper examines emerging forms of multilingualism and multiliteracy in rural India (where the term "literacy" is used broadly here to include digital media literacy and marketing literacy as well as literacy in the traditional sense of the knowledge of a writing system). Here forces of globalization and digital communication have…

Refugee Children in the UK. Education in an Urbanised Society

ERIC Educational Resources Information Center

Rutter, Jill

2006-01-01

Asylum migration causes intense media and political debate. However, little attention has been paid to how forced migrants can rebuild their lives in the UK or elsewhere. This timely book analyzes the social policies that impact on refugee children's education, and: (1) Provides the background to the migration of refugees; (2) Explores how…

Britishness as Racist Nativism: A Case of the Unnamed "Other"

ERIC Educational Resources Information Center

Smith, Heather Jane

2016-01-01

The construct of Britishness, as with nationalism elsewhere in the world, although amorphous and permeable over time, continues to be used by politicians and the media as a powerful exclusionary force. Moreover in England, fundamental British values (FBV), its most recent and official incarnation, now hold particular currency in education policy…

Mass Media Decision in China's Post-Mao Zedong Modernization Program: Some Unanticipated Consequences.

ERIC Educational Resources Information Center

Koo, Charles M.

In 1978, China launched its "Four Modernizations" program, which included modernization in agriculture, industry, national defense, and science and technology. To promote this program and to mobilize the Chinese masses to take a more positive and active attitude toward modernization, the government called upon the forces of the mass…

Democratic Twittering: Microblogging for a More Participatory Social Studies

ERIC Educational Resources Information Center

Krutka, Daniel G.

2014-01-01

Waves of revolutionary actions beginning in late 2010 led to the downfall of dictatorial leaders who had been entrenched in the Arab world for decades. Everyday citizens used social media services to coordinate, communicate, expose, and respond to the oppressive forces that would crush pockets of resistance. The period known as the Arab Spring…

A Study of Suicide and Socioeconomic Factors

ERIC Educational Resources Information Center

Ying, Yung-hsiang; Chang, Koyin

2009-01-01

The topic of suicide has long been an important socioeconomic issue studied in many countries. Suicides inject an atmosphere of unrest into society, and media attention furthers that social uneasiness. From the viewpoint of economics and management, suicide is a waste of human resource: it decreases the labor force in society and deteriorates…

MEDIA

Science.gov Websites

engagement taking place with the Tajikistan Peacekeeping Battalion of the Mobile Forces and the 648th Exercise Eager Lion 2018. (U.S. Army photo by Sgt. 1st Class Patrick J. DeGeorge, 139th Mobile Public . 1st Class Patrick J. DeGeorge, 139th Mobile Public Affairs Detachment) Hi-Res | Photo Gallery MacDill

24 Hours in a Day: A Listening Update to the Time Studies

ERIC Educational Resources Information Center

Janusik, Laura A.; Wolvin, Andrew D.

2009-01-01

Time is an important communication variable that has been impacted by new technology and changed the way people communicate. This study of communication time use by college students provides an update to earlier studies by factoring in computer and telephone use--media that have forced a multitasking approach to communication. Undergraduate…

75 FR 25219 - Privacy Act of 1974; System of Records

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-07

... SYSTEM: Badge and vehicle control records that at a minimum include: Name, Social Security Number (SSN... SYSTEM: 10 U.S.C. 8013, Secretary of the Air Force, Powers and Duties; Department of Defense 5200.08-R... SYSTEM: STORAGE: Electronic storage media. RETRIEVABILITY: Data is retrieved by querying a driver's name...

77 FR 68155 - The Armed Forces Radiobiology Research Institute TRIGA Reactor: Facility Operating License No. R-84

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-15

... a determination by the presiding officer that the filing demonstrates good cause by satisfying the... electronic storage media. Participants may not submit paper copies of their filings unless they seek an... through Friday, excluding government holidays. Participants who believe that they have a good cause for...

Expanded Cinema.

ERIC Educational Resources Information Center

Youngblood, Gene

Today, our environment is created more by television and cinema than by nature. Our view of what human nature is and might be is conditioned by what we see in those media. Films which make use of traditional genres only reinforce traditional views. They do not force us to new ones. But new filmmakers are creating "synaesthetic" cinema, which…

39 CFR 241.4 - Expansion, relocation, and construction of post offices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... factors, environmental causes, or any other actions that would force an immediate relocation from an... of the project, in writing. (3) Send an initial news release to local communications media. (4)(i... the news release, or, space permitting, both. If such information is available at the time, include in...

39 CFR 241.4 - Expansion, relocation, and construction of post offices.

Code of Federal Regulations, 2014 CFR

2014-07-01

... factors, environmental causes, or any other actions that would force an immediate relocation from an... of the project, in writing. (3) Send an initial news release to local communications media. (4)(i... the news release, or, space permitting, both. If such information is available at the time, include in...

39 CFR 241.4 - Expansion, relocation, and construction of post offices.

Code of Federal Regulations, 2012 CFR

2012-07-01

... factors, environmental causes, or any other actions that would force an immediate relocation from an... of the project, in writing. (3) Send an initial news release to local communications media. (4)(i... the news release, or, space permitting, both. If such information is available at the time, include in...

39 CFR 241.4 - Expansion, relocation, and construction of post offices.

Code of Federal Regulations, 2011 CFR

2011-07-01

... factors, environmental causes, or any other actions that would force an immediate relocation from an... of the project, in writing. (3) Send an initial news release to local communications media. (4)(i... the news release, or, space permitting, both. If such information is available at the time, include in...

39 CFR 241.4 - Expansion, relocation, and construction of post offices.

Code of Federal Regulations, 2013 CFR

2013-07-01

... factors, environmental causes, or any other actions that would force an immediate relocation from an... of the project, in writing. (3) Send an initial news release to local communications media. (4)(i... the news release, or, space permitting, both. If such information is available at the time, include in...

Tunneling magnetic force microscopy

NASA Technical Reports Server (NTRS)

Burke, Edward R.; Gomez, Romel D.; Adly, Amr A.; Mayergoyz, Isaak D.

1993-01-01

We have developed a powerful new tool for studying the magnetic patterns on magnetic recording media. This was accomplished by modifying a conventional scanning tunneling microscope. The fine-wire probe that is used to image surface topography was replaced with a flexible magnetic probe. Images obtained with these probes reveal both the surface topography and the magnetic structure. We have made a thorough theoretical analysis of the interaction between the probe and the magnetic fields emanating from a typical recorded surface. Quantitative data about the constituent magnetic fields can then be obtained. We have employed these techniques in studies of two of the most important issues of magnetic record: data overwrite and maximizing data-density. These studies have shown: (1) overwritten data can be retrieved under certain conditions; and (2) improvements in data-density will require new magnetic materials. In the course of these studies we have developed new techniques to analyze magnetic fields of recorded media. These studies are both theoretical and experimental and combined with the use of our magnetic force scanning tunneling microscope should lead to further breakthroughs in the field of magnetic recording.

General scaling relations for locomotion in granular media

NASA Astrophysics Data System (ADS)

Slonaker, James; Motley, D. Carrington; Zhang, Qiong; Townsend, Stephen; Senatore, Carmine; Iagnemma, Karl; Kamrin, Ken

2017-05-01

Inspired by dynamic similarity in fluid systems, we have derived a general dimensionless form for locomotion in granular materials, which is validated in experiments and discrete element method (DEM) simulations. The form instructs how to scale size, mass, and driving parameters in order to relate dynamic behaviors of different locomotors in the same granular media. The scaling can be derived by assuming intrusion forces arise from resistive force theory or equivalently by assuming the granular material behaves as a continuum obeying a frictional yield criterion. The scalings are experimentally confirmed using pairs of wheels of various shapes and sizes under many driving conditions in a common sand bed. We discuss why the two models provide such a robust set of scaling laws even though they neglect a number of the complexities of granular rheology. Motivated by potential extraplanetary applications, the dimensionless form also implies a way to predict wheel performance in one ambient gravity based on tests in a different ambient gravity. We confirm this using DEM simulations, which show that scaling relations are satisfied over an array of driving modes even when gravity differs between scaled tests.

Measuring the nonlinear elastic properties of tissue-like phantoms.

PubMed

Erkamp, Ramon Q; Skovoroda, Andrei R; Emelianov, Stanislav Y; O'Donnell, Matthew

2004-04-01

A direct mechanical system simultaneously measuring external force and deformation of samples over a wide dynamic range is used to obtain force-displacement curves of tissue-like phantoms under plain strain deformation. These measurements, covering a wide deformation range, then are used to characterize the nonlinear elastic properties of the phantom materials. The model assumes incompressible media, in which several strain energy potentials are considered. Finite-element analysis is used to evaluate the performance of this material characterization procedure. The procedures developed allow calibration of nonlinear elastic phantoms for elasticity imaging experiments and finite-element simulations.

Slip-Size Distribution and Self-Organized Criticality in Block-Spring Models with Quenched Randomness

NASA Astrophysics Data System (ADS)

Sakaguchi, Hidetsugu; Kadowaki, Shuntaro

2017-07-01

We study slowly pulling block-spring models in random media. Second-order phase transitions exist in a model pulled by a constant force in the case of velocity-strengthening friction. If external forces are slowly increased, nearly critical states are self-organized. Slips of various sizes occur, and the probability distributions of slip size roughly obey power laws. The exponent is close to that in the quenched Edwards-Wilkinson model. Furthermore, the slip-size distributions are investigated in cases of Coulomb friction, velocity-weakening friction, and two-dimensional block-spring models.

Against conventional wisdom: when the public, the media, and medical practice collide.

PubMed

Jensen, Jakob D; Krakow, Melinda; John, Kevin K; Liu, Miao

2013-01-01

In 2009, the U.S. Preventive Services Task Force released new mammography screening guidelines that sparked a torrent of criticism. The subsequent conflict was significant and pitted the Task Force against other health organizations, advocacy groups, the media, and the public at large. We argue that this controversy was driven by the systematic removal of uncertainty from science communication. To increase comprehension and adherence, health information communicators remove caveats, limitations, and hedging so science appears simple and more certain. This streamlining process is, in many instances, initiated by researchers as they engage in dissemination of their findings, and it is facilitated by public relations professionals, journalists, public health practitioners, and others whose tasks involve using the results from research for specific purposes. Uncertainty is removed from public communication because many communicators believe that it is difficult for people to process and/or that it is something the audience wants to avoid. Uncertainty management theory posits that people can find meaning and value in uncertainty. We define key terms relevant to uncertainty management, describe research on the processing of uncertainty, identify directions for future research, and offer recommendations for scientists, practitioners, and media professionals confronted with uncertain findings. Science is routinely simplified as it is prepared for public consumption. In line with the model of information overload, this practice may increase short-term adherence to recommendations at the expense of long-term message consistency and trust in science.

A brief compendium of correlations and analytical formulae for the thermal field generated by a heat source embedded in porous and purely-conductive media

NASA Astrophysics Data System (ADS)

Conti, P.; Testi, D.; Grassi, W.

2017-11-01

This work reviews and compares suitable models for the thermal analysis of forced convection over a heat source in a porous medium. The set of available models refers to an infinite medium in which a fluid moves over different three heat source geometries: i.e. the moving infinite line source, the moving finite line source, and the moving infinite cylindrical source. In this perspective, the present work presents a plain and handy compendium of the above-mentioned models for forced external convection in porous media; besides, we propose a dimensionless analysis to figure out the reciprocal deviation among available models, helping the selection of the most suitable one in the specific case of interest. Under specific conditions, the advection term becomes ineffective in terms of heat transfer performances, allowing the use of purely-conductive models. For that reason, available analytical and numerical solutions for purely-conductive media are also reviewed and compared, again, by dimensionless criteria. Therefore, one can choose the simplest solution, with significant benefits in terms of computational effort and interpretation of the results. The main outcomes presented in the paper are: the conditions under which the system can be considered subject to a Darcy flow, the minimal distance beyond which the finite dimension of the heat source does not affect the thermal field, and the critical fluid velocity needed to have a significant contribution of the advection term in the overall heat transfer process.

Against conventional wisdom: when the public, the media, and medical practice collide

PubMed Central

2013-01-01

Background In 2009, the U.S. Preventive Services Task Force released new mammography screening guidelines that sparked a torrent of criticism. The subsequent conflict was significant and pitted the Task Force against other health organizations, advocacy groups, the media, and the public at large. We argue that this controversy was driven by the systematic removal of uncertainty from science communication. To increase comprehension and adherence, health information communicators remove caveats, limitations, and hedging so science appears simple and more certain. This streamlining process is, in many instances, initiated by researchers as they engage in dissemination of their findings, and it is facilitated by public relations professionals, journalists, public health practitioners, and others whose tasks involve using the results from research for specific purposes. Analysis Uncertainty is removed from public communication because many communicators believe that it is difficult for people to process and/or that it is something the audience wants to avoid. Uncertainty management theory posits that people can find meaning and value in uncertainty. We define key terms relevant to uncertainty management, describe research on the processing of uncertainty, identify directions for future research, and offer recommendations for scientists, practitioners, and media professionals confronted with uncertain findings. Conclusions Science is routinely simplified as it is prepared for public consumption. In line with the model of information overload, this practice may increase short-term adherence to recommendations at the expense of long-term message consistency and trust in science. PMID:24565173

Using data from colloid transport experiments to parameterize filtration model parameters for favorable conditions

NASA Astrophysics Data System (ADS)

Kamai, Tamir; Nassar, Mohamed K.; Nelson, Kirk E.; Ginn, Timothy R.

2017-04-01

Colloid filtration in porous media spans across many disciplines and includes scenarios such as in-situ bioremediation, colloid-facilitated transport, water treatment of suspended particles and pathogenic bacteria, and transport of natural and engineered nanoparticles in the environment. Transport and deposition of colloid particles in porous media are determined by a combination of complex processes and forces. Given the convoluted physical, chemical, and biological processes involved, and the complexity of porous media in natural settings, it should not come as surprise that colloid filtration theory does not always sufficiently predict colloidal transport, and that there is still a pressing need for improved predictive capabilities. Here, instead of developing the macroscopic equation from pore-scale models, we parametrize the different terms in the macroscopic collection equation through fitting it to experimental data, by optimizing the parameters in the different terms of the equation. This way we combine a mechanistically-based filtration-equation with empirical evidence. The impact of different properties of colloids and porous media are studied by comparing experimental properties with different terms of the correlation equation. This comparison enables insight about different processes that occur during colloid transport and retention under in porous media under favorable conditions, and provides directions for future theoretical developments.

Characterization facility for magneto-optic media and systems

NASA Technical Reports Server (NTRS)

Mansuripur, M.; Fu, H.; Gadetsky, S.; Sugaya, S.; Wu, T. H.; Zambuto, J.; Gerber, R.; Goodman, T.; Erwin, J. K.

1993-01-01

Objectives of this research are: (1) to measure the hysteresis loop, Kerr rotation angle, anisotropy energy profile, Hall voltage, and magnetoresistance of thin-film magneto-optic media using our loop-tracer; (2) measure the wavelength-dependence of the Kerr rotation angle, Theta(sub k), and ellipticity, epsilon(sub k), for thin-film media using our magneto-optic Kerr spectrometer (MOKS); (3) measure the dielectric tensor of thin-film and multilayer samples using our variable-angle magneto-optic ellipsometer (VAMOE); (4) measure the hysteresis loop, coercivity, remanent magnetization, saturation magnetization, and anisotropy energy constant for thin film magnetic media using vibrating sample magnetometry; (5) observe small magnetic domains and investigate their interaction with defects using magnetic force microscopy; (6) perform static read/write/erase experiments on thin-film magneto-optic media using our static test station; (7) integrate the existing models of magnetization, magneto-optic effects, coercivity, and anisotropy in an interactive and user-friendly environment, and analyze the characterization data obtained in the various experiments, using this modeling package; (8) measure focusing- and tracking-error signals on a static testbed, determine the 'feedthrough' for various focusing schemes, investigate the effects of polarization and birefringence, and compare the results with diffraction-based calculations; and (9) measure the birefringence of optical disk substrates using two variable angle ellipsometers.

Endogenous Sheet-Averaged Tension Within a Large Epithelial Cell Colony.

PubMed

Dumbali, Sandeep P; Mei, Lanju; Qian, Shizhi; Maruthamuthu, Venkat

2017-10-01

Epithelial cells form quasi-two-dimensional sheets that function as contractile media to effect tissue shape changes during development and homeostasis. Endogenously generated intrasheet tension is a driver of such changes, but has predominantly been measured in the presence of directional migration. The nature of epithelial cell-generated forces transmitted over supracellular distances, in the absence of directional migration, is thus largely unclear. In this report, we consider large epithelial cell colonies which are archetypical multicell collectives with extensive cell-cell contacts but with a symmetric (circular) boundary. Using the traction force imbalance method (TFIM) (traction force microscopy combined with physical force balance), we first show that one can determine the colony-level endogenous sheet forces exerted at the midline by one half of the colony on the other half with no prior assumptions on the uniformity of the mechanical properties of the cell sheet. Importantly, we find that this colony-level sheet force exhibits large variations with orientation-the difference between the maximum and minimum sheet force is comparable to the average sheet force itself. Furthermore, the sheet force at the colony midline is largely tensile but the shear component exhibits significantly more variation with orientation. We thus show that even an unperturbed epithelial colony with a symmetric boundary shows significant directional variation in the endogenous sheet tension and shear forces that subsist at the colony level.

A prospective study of medical students' perspective of teaching-learning media: reiterating the importance of feedback.

PubMed

Dhaliwal, Upreet

2007-11-01

To enhance successful communication, medical teachers are increasingly using teaching-learning media. To determine medical students' perception of three such media (blackboard, overhead projector, and slides), and to generate recommendations for their optimal use, a prospective questionnaire-based study was carried out among 7th semester medical students of the University College of Medical Sciences and Guru Teg Bahadur Hospital, Delhi. Students made a forced choice between: (1) The three media on 8 questions regarding their advantages and disadvantages and (2) four aspects of a lecture (teaching-learning media, topic, teacher and time of day) regarding which made the lecture most engaging. Resulting data was analysed by Chi-square and Fisher's exact tests. Chalk and blackboard was rated as best in allowing interaction and helping recall (p<0.001 each). The overhead projector was best in providing information pointwise (p<0.001; 67 students, 89.3%, considered this an advantage). More subject matter could be covered per lecture (p=0.001; 58 students, 77.3%, considered this a disadvantage). Slides were best in imparting clinical details (p=0.004), but were sleep inducing (p<0.001). The teacher's style of instruction was most important in making the lecture engaging (p<0.001). The teacher's role in the learning process is important. Students enjoy the slow pace and interaction allowed by blackboard, pointwise information presented by the overhead projector, and the clinical details a slide can provide. The results suggest that the lecture could best be a combination of two or more teaching-learning media. Students' interaction should be encouraged whatever the media used.

TDRS-M NASA Social

NASA Image and Video Library

2017-08-17

NASA astronauts Nicole Mann, left, and Steve Bowen speak to members of social media in the Kennedy Space Center’s Press Site auditorium. With them on the right is Emily Furfaro of the NASA Social Media Team. The briefing focused on preparations to launch NASA's Tracking and Data Relay Satellite, TDRS-M. The latest spacecraft destined for the agency's constellation of communications satellites, TDRS-M will allow nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop a United Launch Alliance Atlas V rocket is scheduled to take place from Space Launch Complex 41 at Cape Canaveral Air Force Station at 8:03 a.m. EDT Aug. 18.

Electronic collaboration: Some effects of telecommunication media and machine intelligence on team performance

NASA Technical Reports Server (NTRS)

Wellens, A. Rodney

1991-01-01

Both NASA and DoD have had a long standing interest in teamwork, distributed decision making, and automation. While research on these topics has been pursued independently, it is becoming increasingly clear that the integration of social, cognitive, and human factors engineering principles will be necessary to meet the challenges of highly sophisticated scientific and military programs of the future. Images of human/intelligent-machine electronic collaboration were drawn from NASA and Air Force reports as well as from other sources. Here, areas of common concern are highlighted. A description of the author's research program testing a 'psychological distancing' model of electronic media effects and human/expert system collaboration is given.

Orbital ATK CRS-7 Post Launch News Conference

NASA Image and Video Library

2017-04-18

Members of the news media attend a press conference at NASA's Kennedy Space Center in Florida, after the launch of the Orbital ATK Cygnus pressurized cargo module atop a United Launch Alliance Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station. It was Orbital ATK's seventh commercial resupply services mission to the International Space Station. Liftoff was at 11:11 a.m. EDT. Speaking to the media are, from left, George Diller, NASA Kennedy Communications; Joel Montalbano, deputy manager, International Space Station Program, NASA Johnson Space Center in Houston; Frank Culbertson, president, Orbital ATK Space Systems Group; and Vern Thorp, program manager, commercial missions, United Launch Alliance.

Special Inspector General for Iraq Reconstruction Quarterly Report and Semiannual Report to the United States Congress

DTIC Science & Technology

2010-01-30

Kickback Act and making false statements 7/20/2007 14 months in prison; 2 years supervised release; $6,000 fine; $17,964 restitution Anthony Martin ...usf-iraq.com/news/press-briefings/generals-david- petrae - us-and-ray-odierno-take-media-questions-following-the- establishment-of-united-states-forces

Joint Chiefs of Staff > Media > News

Science.gov Websites

Facebook on Flickr Joint Chiefs Army Chief of Staff Marine Corps Commandant Chief of Naval Operations Air Force Chief of Staff Chief of National Guard Bureau Biographies Directorates Directorates of Management Readout of Chairman of the Joint Chiefs of Staff Gen. Dunford's Meeting with Chief of the Turkish General

Radio and the Art of Resistance: A Public Pedagogy of the Airwaves

ERIC Educational Resources Information Center

Darder, Antonia

2011-01-01

The politics of the airwaves should be of vital concern to critical democracy, given the expanding realm of neoliberalism and its deeply homogenizing impact on social, political and economic relations everywhere. In light of the privatizing forces that control the media today, the article considers the manner in which community radio can provide…

Separate but Equal: Segregated Religious Education in Egypt's Public Schools

ERIC Educational Resources Information Center

Isaac, John

2012-01-01

The Arab Spring exposed the hidden secrets of Egyptian society to the global community. In spite of the insatiable media attention paid to the Mubarak regime and the toll it took on the entire country, Egypt's education system received little attention. For decades, Egypt's public schools have forced students to attend segregated classes, based on…

SMEs and Electronic Commerce: A Departure from the Traditional Prioritisation of Training?

ERIC Educational Resources Information Center

Barry, Helen; Milner, Brigid

2002-01-01

A survey of 56 small/medium-sized Irish enterprises showed that 46% were highly proficient in electronic commerce, 42% were at the basic level. Media pressure significantly influenced adoption. In 40% of firms, owner-managers were the driving force. E-commerce was not yet business critical and relevant training was not yet a comprehensive…

Gooey Stuff, Intra-Activity, and Differential Obesities: Foregrounding Agential Adiposity within Childhood Obesity Stories

ERIC Educational Resources Information Center

Land, Nicole

2015-01-01

In Canada, forces such as the media, medical discourse, and public policy work to position childhood obesity as increased body fat content or excess adiposity due to various personal, social, and economic factors. Drawing on Barad's "agential realist ontology", this article aims to inhabit-with obesity in an effort to disrupt dominant…

Electromagnetic Momentum in Magnetic Media and the Abraham-Minkowski Controversy

ERIC Educational Resources Information Center

Jimenez, J. L.; Campos, I.; Lopez-Marino, M. A.

2011-01-01

We explore the consequences of a force density, [image omitted], studied by some authors, for the device designed by Lai (1980 "Am. J. Phys. 48" 658) to analyse which definition of electromagnetic momentum density, either Minkowski's or Abraham's, is consistent with mechanical torques that arise from the change in time of a magnetic field, which…

Reconceptualising Musical Learning: New Media, Identity and Community in Music Education

ERIC Educational Resources Information Center

Partti, Heidi; Karlsen, Sidsel

2010-01-01

Societal and technological progresses have created a multitude of new ways for people to engage with music, and as a result music can nowadays be learned from an ever-expanding variety of sources. In this article, we engage in a theoretical exploration of the underpinning societal forces that have enabled this expansion, as well as its…

Emotional Impact of a Video-Based Suicide Prevention Program on Suicidal Viewers and Suicide Survivors

ERIC Educational Resources Information Center

Bryan, Craig J.; Dhillon-Davis, Luther E.; Dhillon-Davis, Kieran K.

2009-01-01

In light of continuing concerns about iatrogenic effects associated with suicide prevention efforts utilizing video-based media, the impact of emotionally-charged videos on two vulnerable subgroups--suicidal viewers and suicide survivors--was explored. Following participation in routine suicide education as a part of the U.S. Air Force Suicide…

32 CFR 806.27 - Samples of Air Force FOIA processing documents.

Code of Federal Regulations, 2014 CFR

2014-07-01

... scientific institution or news media/all others). As a result, you (if commercial category) are required to pay all document search, review and duplication costs over $15.00. (or) As a result, you (if... result, you will be provided the first 2 hours of search time and the first 100 pages free of charge; you...

32 CFR 806.27 - Samples of Air Force FOIA processing documents.

Code of Federal Regulations, 2011 CFR

2011-07-01

... scientific institution or news media/all others). As a result, you (if commercial category) are required to pay all document search, review and duplication costs over $15.00. (or) As a result, you (if... result, you will be provided the first 2 hours of search time and the first 100 pages free of charge; you...

32 CFR 806.27 - Samples of Air Force FOIA processing documents.

Code of Federal Regulations, 2013 CFR

2013-07-01

... scientific institution or news media/all others). As a result, you (if commercial category) are required to pay all document search, review and duplication costs over $15.00. (or) As a result, you (if... result, you will be provided the first 2 hours of search time and the first 100 pages free of charge; you...

32 CFR 806.27 - Samples of Air Force FOIA processing documents.

Code of Federal Regulations, 2010 CFR

2010-07-01

... scientific institution or news media/all others). As a result, you (if commercial category) are required to pay all document search, review and duplication costs over $15.00. (or) As a result, you (if... result, you will be provided the first 2 hours of search time and the first 100 pages free of charge; you...

32 CFR 806.27 - Samples of Air Force FOIA processing documents.

Code of Federal Regulations, 2012 CFR

2012-07-01

... scientific institution or news media/all others). As a result, you (if commercial category) are required to pay all document search, review and duplication costs over $15.00. (or) As a result, you (if... result, you will be provided the first 2 hours of search time and the first 100 pages free of charge; you...

Blended Learning via Mobile Social Media & Implementation of "EDMODO" in Reading Classes

ERIC Educational Resources Information Center

Yagci, Tahsin

2015-01-01

Almost there is nowhere that we don't use permeated smart technology. Increasingly developing mobile and wireless innovations forced us to integrate them to all fields in our lives. The latest trend in education is now blended learning and applications of mobile learning in educational environments. Pervasive and augmented usage of social media…

NASA Social Briefing on Planet-Hunting Mission Launch

NASA Image and Video Library

2018-04-15

Social Media participants gathered at NASA’s Kennedy Space Center Sunday, April 15 to hear from NASA and its partners about the agnecy’s next-generation planet hunting satellite. NASA’s Transiting Exoplanet Survey Satellite (TESS) is scheduled to launch April 16 on a SpaceX Falcon 9 rocket, from Cape Canaveral Air Force Station in Florida.

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

NASA Chief Scientist Jim Green discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

Armed Conflict: A Model for Understanding and Intervention

ERIC Educational Resources Information Center

Death Studies, 2013

2013-01-01

Acts of deadly violence give rise to powerful emotions and trigger pre-programmed responses that often cause affected persons, including leaders, media, armed forces, and the general public, to act in ways that aggravate the situation and feed into cycles of violence. In this article, a model of the cycle of violence is presented that facilitates…

Special Operations, Irregular Warfare, and Operational Art: A Theory of Special Operations

DTIC Science & Technology

2013-12-10

is mostly but not wholly a land phenomenon. Naval forces have combatted maritime irregulars such as pirates for millennia, for example see: Plutarch ...SW2502SocialMediaAndUW.html (accessed June 15, 2013). Plaster, John L. SOG: Secret Wars of America’s Commandos in Vietnam. New York: Simon & Schuster, 1997. Plutarch

USNAVSO/4th Fleet

Science.gov Websites

. FOURTH Fleet (USNAVSO/FOURTHFLT) employs maritime forces in cooperative maritime security operations in €­(Hidden)‬ USNAVSO/4th Fleet News Retrieving Data Links Secretary of the Navy Chief of Naval Operations Department of Defense U.S. Southern Command SOCIAL MEDIA Quick Links US Navy Recruiting | No Fear Act Data

Communications at the Crossroads: Parity and Perceptions of Minority Participation.

ERIC Educational Resources Information Center

Ellis, Dwight M.

In some areas of employment in mass communications Blacks and other minorities have made impressive gains, but in others, such as the newspaper industry, there is a distinct lack of minorities in the work force. The chance that this situation will change is highly likely because the media industries in America are finding it necessary to diversify…

Section 1: Looking Broadly at the Politics of Privatization: The Politics of Privatization in American Education

ERIC Educational Resources Information Center

Boyd, William L.

2007-01-01

The long-sustained effort of conservatives and their think tanks and media outlets to win support for school choice, market forces, and privatization schemes in education is paying off. But it is encountering steady resistance from the public education establishment and its supporting teachers' unions. Actions, reactions, strategies, and the…

¿Qué es un repelente de insectos?

EPA Pesticide Factsheets

Según la ley de pesticidas, estos productos son cualquier sustancia o mezcla de sustancias destinadas a lo siguiente: prevenir; eliminar; repeler; mitigar cualquier peste. (Mitigar significa reducir el efecto de algo).

PubMed

López Gómez, Juan José; Pérez Castrillón, José Luis; Romero Bobillo, Enrique; De Luis Román, Daniel A

2016-11-29

La obesidad interfiere con el metabolismo óseo a través de factores mecánicos, hormonales e inflamatorios. El principal tratamiento de dicha enfermedad es la dieta, modificación de la cantidad y tipo de alimento. Este tratamiento nutricional tiene una influencia sobre el metabolismo óseo en dos sentidos: modifica el efecto del sobrepeso y la obesidad sobre el hueso e interviene directamente en el turnoveróseo a través de las características de los nutrientes utilizados. Esta revisión analiza la evidencia del efecto sobre el hueso del descenso de peso y del patrón dietético utilizado. Por otra parte, se valorarán las modificaciones que se pueden realizar en la dieta indicada en un paciente obeso para prevenir la pérdida ósea, a corto y largo plazo, y disminuir el riesgo de fractura.

Evolución de planetas gigantes y posibilidades de su detección directa

NASA Astrophysics Data System (ADS)

Brunini, A.; Benvenuto, O. G.

Desde la reciente detección de planetas gigantes orbitando estrellas cercanas de tipo solar por medio de efecto Doppler, uno de los principales problemas, en cuanto al estudio de los sistemas planetarios extrasolares, se refiere a la posibilidad de obtener evidencia directa de su existencia. Esto parece ser factible gracias a que en un futuro cercano entrarán en operación algunos telescopios especialmente adecuados a estos propósitos. Por tal motivo, hemos comenzado desde hace un tiempo un esfuerzo en cuanto al estudio de la evolución planetaria. A tales efectos hemos adaptado el código de evolución estelar de nuestro Observatorio al caso planetario. Las principales diferencias entre el caso estelar y el planetario se encuentran en la ecuación de estado. A tales fines hemos incluído la reciente ecuación de estado de Saumon, Chabrier y Van Horn, las opacidades radiativas de Guillot et al., procesos de quema de Deuterio, etc. También se ha considerado la posible existencia de fases de hielo y roca en el interior planetario. Por el momento hemos despreciado los efectos de la rotación planetaria. Con este código hemos computado la evolución de planetas con masas desde 10 hasta 0.3 masas de Júpiter. Utilizando nuestros resultados numéricos discutimos la detectabilidad de estos objetos en condiciones realistas.

Studies of elasticity, sound propagation and attenuation of acoustic modes in granular media: final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makse, Hernan A.; Johnson, David L.

2014-09-03

This is the final report describing the results of DOE Grant # DE-FG02-03ER15458 with original termination date of April 31, 2013, which has been extended to April 31, 2014. The goal of this project is to develop a theoretical and experimental understanding of sound propagation, elasticity and dissipation in granular materials. The topic is relevant for the efficient production of hydrocarbon and for identifying and characterizing the underground formation for storage of either CO 2 or nuclear waste material. Furthermore, understanding the basic properties of acoustic propagation in granular media is of importance not only to the energy industry, butmore » also to the pharmaceutical, chemical and agricultural industries. We employ a set of experimental, theoretical and computational tools to develop a study of acoustics and dissipation in granular media. These include the concept effective mass of granular media, normal modes analysis, statistical mechanics frameworks and numerical simulations based on Discrete Element Methods. Effective mass measurements allow us to study the mechanisms of the elastic response and attenuation of acoustic modes in granular media. We perform experiments and simulations under varying conditions, including humidity and vacuum, and different interparticle force-laws to develop a fundamental understanding of the mechanisms of damping and acoustic propagation in granular media. A theoretical statistical approach studies the necessary phase space of configurations in pressure, volume fraction to classify granular materials.« less

The effect of a microscale fracture on dynamic capillary pressure of two-phase flow in porous media

NASA Astrophysics Data System (ADS)

Tang, Mingming; Lu, Shuangfang; Zhan, Hongbin; Wenqjie, Guo; Ma, Huifang

2018-03-01

Dynamic capillary pressure (DCP) effects, which is vital for predicting multiphase flow behavior in porous media, refers to the injection rate dependence capillary pressure observed during non-equilibrium displacement experiments. However, a clear picture of the effects of microscale fractures on DCP remains elusive. This study quantified the effects of microscale fractures on DCP and simulated pore-scale force and saturation change in fractured porous media using the multiphase lattice Boltzmann method (LBM). Eighteen simulation cases were carried out to calculate DCP as a function of wetting phase saturation. The effects of viscosity ratio and fracture orientation, aperture and length on DCP and DCP coefficient τ were investigated, where τ refers to the ratio of the difference of DCP and static capillary pressure (SCP) over the rate of wetting-phase saturation change versus time. Significant differences in τ values were observed between unfractured and fractured porous media. The τ values of fractured porous media were 1.1  × 104 Pa ms to 5.68 × 105 Pa ms, which were one or two orders of magnitude lower than those of unfractured porous media with a value of 4 × 106 Pa. ms. A horizontal fracture had greater effects on DCP and τ than a vertical fracture, given the same fracture aperture and length. This study suggested that a microscale fracture might result in large magnitude changes in DCP for two-phase flow.

Force Density Function Relationships in 2-D Granular Media

NASA Technical Reports Server (NTRS)

Youngquist, Robert C.; Metzger, Philip T.; Kilts, Kelly N.

2004-01-01

An integral transform relationship is developed to convert between two important probability density functions (distributions) used in the study of contact forces in granular physics. Developing this transform has now made it possible to compare and relate various theoretical approaches with one another and with the experimental data despite the fact that one may predict the Cartesian probability density and another the force magnitude probability density. Also, the transforms identify which functional forms are relevant to describe the probability density observed in nature, and so the modified Bessel function of the second kind has been identified as the relevant form for the Cartesian probability density corresponding to exponential forms in the force magnitude distribution. Furthermore, it is shown that this transform pair supplies a sufficient mathematical framework to describe the evolution of the force magnitude distribution under shearing. Apart from the choice of several coefficients, whose evolution of values must be explained in the physics, this framework successfully reproduces the features of the distribution that are taken to be an indicator of jamming and unjamming in a granular packing. Key words. Granular Physics, Probability Density Functions, Fourier Transforms

KSC-2015-1302

NASA Image and Video Library

2015-02-07

CAPE CANAVERAL, Fla. – Col. D. Jason Cothern, Space Demonstrations Division chief at Kirtland Air Force Base in Albuquerque, New Mexico, listens to a question from a member of the news media during a briefing regarding NOAA’s Deep Space Climate Observatory spacecraft, or DSCOVR. DSCOVR will launch aboard a SpaceX Falcon 9 rocket. The mission is a partnership between NOAA, NASA and the U.S. Air Force. DSCOVR will maintain the nation's real-time solar wind monitoring capabilities which are critical to the accuracy and lead time of NOAA's space weather alerts and forecasts. To learn more about DSCOVR, visit http://www.nesdis.noaa.gov/DSCOVR. Photo credit: NASA/Kim Shiflett

The relationship between dielectrophoretic and impedance response of dielectric particles immersed in aqueous media

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bahaj, A.E.; Bailey, A.G.

1985-09-01

Dielectrophoretic force measurements on isolated 50-..mu..m diameter particles of divinylbenzene (DVB) suspended in aqueous solutions show that force is dependent on relaxation mechanisms present at the particle-liquid interface. Measurements on single particles have been extended to measurements on populations of particles. The impedance of aqueous suspensions of particles contained in a gold-plated electrode test cell has been measured over a range of frequency. Data are presented in the form of Cole-Cole plots. It is shown that the dielectrophoretic response of single particles can be related to the frequency-dependent impedance behavior of suspensions of similar particles.

Iron-platinum-coated carbon nanocone probes on tipless cantilevers for high resolution magnetic force imaging.

PubMed

Chen, I-Chen; Chen, Li-Han; Gapin, Andrew; Jin, Sungho; Yuan, Lu; Liou, Sy-Hwang

2008-02-20

High coercivity iron-platinum-coated carbon nanocones (CNCs) have been fabricated for magnetic force microscopy (MFM) by direct-current plasma-enhanced chemical vapor deposition growth of nanocones on tipless cantilevers followed by sputtering and annealing of the FePt film. The FePt-coated CNC probe has many localized magnetic stray fields due to the high-aspect-ratio geometry and small radius of the tip. The MFM imaging on magnetic recording media was performed using CNC probes and compared with the imaging by FePt-coated silicon probes. An image with 20 nm lateral resolution has been demonstrated.

The self-propulsion of a helix in granular matter

NASA Astrophysics Data System (ADS)

Valdes, Rogelio; Angeles, Veronica; de La Calleja, Elsa; Zenit, Roberto

2017-11-01

The effect of the shape of helicoidal on the displacement of magnetic robots in granular media is studied experimentally. We quantify the influences of three main parameters of the shape of the helicoidal swimmers: body diameter, step, and the angle. We compare the experimental measurements with an empirically modified resistive force theory prediction that accounts for the static friction coefficient of the particles of the granular material, leading to good agreement. Comparisons are also made with the granular resistive force theory proposed by Goldman and collaborators. We found an optimal helix angle to produce movement and determined a relationship between the swimmer size and speed.

GOES-S Prelaunch News Conference

NASA Image and Video Library

2018-02-27

In the Kennedy Space Center's Press Site auditorium, and Kathy Winters, launch weather officer for the U.S. Air Force 45th Weather Squadron at Cape Canaveral Air Force Station, speaks to members of the media at a prelaunch news conference about National Oceanic and Atmospheric Administration's, or NOAA's, Geostationary Operational Environmental Satellite, or GOES-S. The GOES series of satellites will significantly improve the detection and observation of environmental phenomena that directly affect public safety, protection of property and the nation's economic health and prosperity. GOES-S is slated to lift off at 5:02 p.m. EST on March 1, 2018 aboard a United Launch Alliance Atlas V rocket.

Time-Dependent Measure of a Nano-Scale Force-Pulse Driven by the Axonemal Dynein Motors in Individual Live Sperm Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, M J; Rudd, R E; McElfresh, M W

Nano-scale mechanical forces generated by motor proteins are crucial to normal cellular and organismal functioning. The ability to measure and exploit such forces would be important to developing motile biomimetic nanodevices powered by biological motors for Nanomedicine. Axonemal dynein motors positioned inside the sperm flagellum drive microtubule sliding giving rise to rhythmic beating of the flagellum. This force-generating action makes it possible for the sperm cell to move through viscous media. Here we report new nano-scale information on how the propulsive force is generated by the sperm flagellum and how this force varies over time. Single cell recordings reveal discretemore » {approx}50 ms pulses oscillating with amplitude 9.8 {+-} 2.6 nN independent of pulse frequency (3.5-19.5 Hz). The average work carried out by each cell is 4.6 x 10{sup -16} J per pulse, equivalent to the hydrolysis of {approx}5,500 ATP molecules. The mechanochemical coupling at each active dynein head is {approx}2.2 pN/ATP, and {approx}3.9 pN per dynein arm, in agreement with previously published values obtained using different methods.« less

Tuning coercive force by adjusting electric potential in solution processed Co/Pt(111) and the mechanism involved

PubMed Central

Chang, Cheng-Hsun-Tony; Kuo, Wei-Hsu; Chang, Yu-Chieh; Tsay, Jyh-Shen; Yau, Shueh-Lin

2017-01-01

A combination of a solution process and the control of the electric potential for magnetism represents a new approach to operating spintronic devices with a highly controlled efficiency and lower power consumption with reduced production cost. As a paradigmatic example, we investigated Co/Pt(111) in the Bloch-wall regime. The depression in coercive force was detected by applying a negative electric potential in an electrolytic solution. The reversible control of coercive force by varying the electric potential within few hundred millivolts is demonstrated. By changing the electric potential in ferromagnetic layers with smaller thicknesses, the efficiency for controlling the tunable coercive force becomes higher. Assuming that the pinning domains are independent of the applied electric potential, an electric potential tuning-magnetic anisotropy energy model was derived and provided insights into our knowledge of the relation between the electric potential tuning coercive force and the thickness of the ferromagnetic layer. Based on the fact that the coercive force can be tuned by changing the electric potential using a solution process, we developed a novel concept of electric-potential-tuned magnetic recording, resulting in a stable recording media with a high degree of writing ability. PMID:28255160

Laser scanning confocal microscopy and laser tweezers based experiments to understand dentine-bacteria interactions

NASA Astrophysics Data System (ADS)

Peng, Sum Chee; Mohanty, Samarendra; Gupta, P. K.; Kishen, Anil

2007-02-01

Failure of endodontic treatment is commonly due to Enterococcal infection. In this study influence of chemical treatments of type-I collagen membrane by chemical agents commonly used in endodontic treatment on Enterococcus faecalis cell adherence was evaluated. In order to determine the change in number of adhering bacteria after chemical treatment, confocal laser scanning microscopy was used. For this, overnight culture of E faecalis in All Culture broth was applied to chemically treated type-I collagen membrane. It was found that Ca(OH) II treated groups had statistically significant (p value=0.05) increase in population of bacteria adherence. The change in adhesion force between bacteria and collagen was determined by using optical tweezers (1064 nm). For this experiment, Type-I collagen membrane was soaked for 5 mins in a media that contained 50% all culture media and 50% saturated Ca(OH) II . The membrane was spread on the coverslip, on which diluted bacterial suspension was added. The force of laser tweezers on the bacteria was estimated at different trap power levels using viscous drag method and trapping stiffness was calculated using Equipartition theorem method. Presence of Ca(OH) II was found to increase the cell-substrate adherence force from 0.38pN to >2.1pN. Together, these experiments show that it was highly probable that the increase in adherence to collagen was due to a stronger adhesion in the presence of Ca (OH) II.

Social Media: Gateway to Public Preparedness and Understanding of GeoHazards

NASA Astrophysics Data System (ADS)

Ballmann, J. E.; Bohon, W.; Bartel, B. A.

2016-12-01

The clear, timely communication of natural hazards information is critical to providing the public with the tools and information they need to make informed decisions before, during, and after events such as earthquakes, tsunamis, and volcanic eruptions. For the geohazards community, this is a multi-sector collaboration involving partners from national, state, and local governments, businesses, educational organizations, non-profit groups, and scientific institutions, for the benefit and participation of the whole community. Communications channels must be clear, consistent, and unified for the sake of maximum reach. One method of public communication that has proven to be particularly effective in disseminating hazards-related information is social media. The broad social and geographic reach of social media coupled with its ubiquitous use in all age groups makes it a powerful way to reach large segments of the population. Social media is already widely used by mass media and scientific organizations to communicate science and hazards. However, it is important that science organizations present a united and clear message, particularly about hazards preparation and response. The Southern California Earthquake Center (SCEC), UNAVCO, and the Incorporated Research Institutions for Seismology (IRIS) have created a Joint Social Media Task Force. The objective of this collaboration is 1) to build social media communities and improve the reach of science messaging, 2) to create and present consistent and clear messaging across social media platforms and regional facilities, 3) to promote outstanding products and educational information , 4) to assist and collaborate in regional, national and international efforts (TweetChats, Reddit fora, ShakeOut, etc.) and 5) to assist and support the efforts of FEMA, the USGS and other partner organizations during crisis situations. Here, we outline the difficulties and successes of creating such an alliance and provide a road map forward showing ways that diverse organizations can collaborate to improve and support science and hazards-related social media dissemination.

Criteria for Applying the Lucas-Washburn Law.

PubMed

Li, Kewen; Zhang, Danfeng; Bian, Huiyuan; Meng, Chao; Yang, Yanan

2015-09-14

Spontaneous imbibition happens in many natural and chemical engineering processes in which the mean advancing front usually follows Lucas-Washburn's law. However it has been found that the scaling law does not apply in many cases. There have been few criteria to determine under what conditions the Washburn law works. The effect of gravity on spontaneous imbibition in porous media was investigated both theoretically and experimentally. The mathematical model derived analytically was used to calculate the imbibition rates in porous media with different permeabilities. The results demonstrated that the effect of gravity on spontaneous imbibition was governed by the hydraulic conductivity of the porous media (permeability of the imbibition systems). The criteria for applying the Lucas-Washburn law have been proposed. The effect of gravity becomes more apparent with the increase in permeability or with the decrease in CGR number (the ratio of capillary pressure to gravity forces) and may be ignored when the CGR number is less than a specific value N(*)(cg) ≅ 3.0. The effect of gravity on imbibition in porous media can be modeled theoretically. It may not be necessary to conduct spontaneous imbibition experiments horizontally in order to exclude the effect of gravity, as has been done previously.

Mineral and organic growing media have distinct community structure, stability and functionality in soilless culture systems.

PubMed

Grunert, Oliver; Hernandez-Sanabria, Emma; Vilchez-Vargas, Ramiro; Jauregui, Ruy; Pieper, Dietmar H; Perneel, Maaike; Van Labeke, Marie-Christine; Reheul, Dirk; Boon, Nico

2016-01-05

The choice of soilless growing medium for plant nutrition, growth and support is crucial for improving the eco-sustainability of the production in horticultural systems. As our current understanding of the functional microbial communities inhabiting this ecosystem is still limited, we examined the microbial community development of the two most important growing media (organic and mineral) used in open soilless horticultural systems. We aimed to identify factors that influence community composition over time, and to compare the distribution of individual taxa across growing media, and their potential functionality. High throughput sequencing analysis revealed a distinctive and stable microbial community in the organic growing medium. Humidity, pH, nitrate-N, ammonium-N and conductivity were uncovered as the main factors associated with the resident bacterial communities. Ammonium-N was correlated with Rhizobiaceae abundance, while potential competitive interactions among both Methylophilaceae and Actinobacteridae with Rhizobiaceae were suggested. Our results revealed that soilless growing media are unique niches for diverse bacterial communities with temporal functional stability, which may possibly impact the resistance to external forces. These differences in communities can be used to develop strategies to move towards a sustainable horticulture with increased productivity and quality.

A reusable microfluidic plate with alternate-choice architecture for assessing growth preference in tissue culture.

PubMed

Wittig, John H; Ryan, Allen F; Asbeck, Peter M

2005-05-15

We present the design of a chamber to evaluate in vitro how species and concentrations of soluble molecules control features of cell growth-potentially including cell proliferation, cell motility, process extension, and process termination. We have created a reusable cell culture plate that integrates a microfluidic media delivery network with standard cell culture environment. The microfluidic network delivers a stream of cell culture media with a step-like concentration gradient down a 50-100 microm wide microchannel called the presentation region. Migrating cells or growing cell processes freely choose between the two distinct chemical environments in the presentation region, but they are forced to exclusively choose either one environment or the other when they grow past a physical barrier acting as a decision point. Our fabrication technique requires little specialized equipment, and can be carried out in approximately 4 days per plate. We demonstrate the effectiveness of our plates as neurites from spiral ganglion explants preferentially grow in media containing neurotrophin-3 (NT-3) as opposed to media without NT-3. Our design could be used without modification to study dissociated cell responses to soluble growth cues, and for behavioral screening of small motile organisms.

Macro Trends and the Future of Public Health Practice.

PubMed

Erwin, Paul Campbell; Brownson, Ross C

2017-03-20

Public health practice in the twenty-first century is in a state of significant flux. Several macro trends are impacting the current practice of governmental public health and will likely have effects for many years to come. These macro trends are described as forces of change, which are changes that affect the context in which the community and its public health system operate. This article focuses on seven such forces of change: the Patient Protection and Affordable Care Act, public health agency accreditation, climate change, health in all policies, social media and informatics, demographic transitions, and globalized travel. Following the description of each of these, this article then turns to possible approaches to measuring, tracking, and understanding the impact of these forces of change on public health practice, including the use of evidence-based public health, practice-based research, and policy surveillance.

Nonlinear Acoustic Propagation into the Seafloor

NASA Astrophysics Data System (ADS)

McDonald, B. Edward

2006-05-01

Explosions near the seafloor result in shock waves entering a much more complicated medium than water or air. Nonlinearities may be increased by two processes inherent to granular media: (1) a poroelastic nonlinearity comparable to the addition of bubbles to water, and (2) the Hertz force resulting from elastic deformation of grains, proportional to the Youngs modulus of the grains times the strain rate to the power 3/2. These two types of nonlinearity for shock propagation into the seafloor are investigated using a variant of the NPE model. The traditional Taylor series expansion of the equation of state (pressure as a function of density) is not appropriate to the Hertz force in the limit of small strain. We present a simple nonlinear wave equation model for compressional waves in marine sediments that retains the Hertz force explicitly with overdensity to the power 3/2. Numerical results for shock propagation are compared with similarity solutions for quadratic nonlinearity and for the fractional nonlinearity of the Hertz force.

Developing a Magnetic Resonance Imaging measurement of the forces within 3D granular materials under external loads

NASA Astrophysics Data System (ADS)

Elrington, Stefan; Bertrand, Thibault; Frey, Merideth; Shattuck, Mark; O'Hern, Corey; Barrett, Sean

2014-03-01

Granular materials are comprised of an ensemble of discrete macroscopic grains that interact with each other via highly dissipative forces. These materials are ubiquitous in our everyday life ranging in scale from the granular media that forms the Earth's crust to that used in agricultural and pharmaceutical industries. Granular materials exhibit complex behaviors that are poorly understood and cannot be easily described by statistical mechanics. Under external loads individual grains are jammed into place by a network of force chains. These networks have been imaged in quasi two-dimensional and on the outer surface of three-dimensional granular materials. Our goal is to use magnetic resonance imaging (MRI) to detect contact forces deep within three-dimensional granular materials, using hydrogen-1 relaxation times as a reporter for changes in local stress and strain. To this end, we use a novel pulse sequence to narrow the line width of hydrogen-1 in rubber. Here we present our progress to date, and prospects for future improvements.

Equivalence of expressions for the radiation force on cylinders and application to elliptical cylinders

NASA Astrophysics Data System (ADS)

Wei, Wei; Marston, Philip L.

2005-09-01

Using an appropriate grouping of terms, a radiation force expression for cylinders in a standing wave based on far-field scattering [W. Wei, D. B. Thiessen, and P. L. Marston, J. Acoust. Soc. Am. 116, 202-208 (2004)] is transformed to an expression given elsewhere [F. G. Mitri, Eur. Phys. J. B 44, 71-78 (2005)]. Mitri's result is from a near-field derivation for the specific case of a circular cylinder. In the usual case, in an ideal lossless media the far-field derivation is not an approximation. The far-field derivation also applies to noncircular objects having mirror symmetry about the incident wave vector. Some general and historical aspects of far-field derivations of optical and acoustical radiation force (going back to 1909) will be noted. Our formulation yields a simple low-frequency approximation for the radiation force on elliptical cylinders by introducing approximations for the partial-wave scattering coefficients of elliptical cylinders first derived by Rayleigh. [Work supported by NASA.

Non-equilibrium forces drive the anomalous diffusion of telomeres in the nucleus of mammalian cells

NASA Astrophysics Data System (ADS)

Stadler, Lorenz; Weiss, Matthias

2017-11-01

Telomeres are vital nucleotide sequences at both ends of each chromosome, and their motion reports on the local dynamics of decondensed chromatin in the nucleus of interphase cells. Here, we show that the previously reported subdiffusive motion of telomeres is driven by non-equilibrium cytoskeletal forces. In particular, breaking down microtubules leads to a significantly reduced generalized diffusion coefficient of telomeres. This translates into a markedly reduced effective temperature in the stochastic forces that govern the telomeres’ random walk. Moreover, telomere motion in cells that lack microtubules is well described by the monomer dynamics of a Rouse polymer that is embeddded in a viscoelastic medium. In contrast, active cytoskeletal forces in untreated cells override the environment’s elastic contributions, resulting in the well-known scaling for conventional Rouse dynamics in viscous media. Our data highlight that even subdiffusive motion in cells in most cases may not be a simple thermal transport process but rather is driven by non-equilibrium events.

KSC-06pd1278

NASA Image and Video Library

2006-06-28

KENNEDY SPACE CENTER, FLA. - At the Cape Canaveral weather station in Florida, workers release an upper-level weather balloon while several newscasters watch. The release of the balloon was part of a media tour prior to the launch of Space Shuttle Discovery on mission STS-121 July 1. The radar-tracked balloon detects wind shears that can affect a shuttle launch. At the facility, which is operated by the U.S. Air Force 45th Weather Squadron, media saw the tools used by the weather team to create the forecast for launch day. They received a briefing on how the launch weather forecast is developed by Shuttle Weather Officer Kathy Winters and met the forecasters for the space shuttle and the expendable launch vehicles. Also participating were members of the Applied Meteorology Unit who provide special expertise to the forecasters by analyzing and interpreting unusual or inconsistent weather data. The media were able to see the release of the Rawinsonde weather balloon carrying instruments aloft to be used as part of developing the forecast. Photo credit: NASA/George Shelton

KSC-06pd1276

NASA Image and Video Library

2006-06-28

KENNEDY SPACE CENTER, FLA. - At the Cape Canaveral weather station in Florida, a member of the weather team looks over the weather balloons inside. The release of a Rawinsonde weather balloon was planned as part of a media tour prior to the launch of Space Shuttle Discovery on mission STS-121 July 1. At the facility, which is operated by the U.S. Air Force 45th Weather Squadron, media saw the tools used by the weather team to create the forecast for launch day. They received a briefing on how the launch weather forecast is developed by Shuttle Weather Officer Kathy Winters and met the forecasters for the space shuttle and the expendable launch vehicles. Also participating were members of the Applied Meteorology Unit who provide special expertise to the forecasters by analyzing and interpreting unusual or inconsistent weather data. The media were able to see the release of the Rawinsonde weather balloon carrying instruments aloft to be used as part of developing the forecast. Photo credit: NASA/George Shelton

KSC-06pd1277

NASA Image and Video Library

2006-06-28

KENNEDY SPACE CENTER, FLA. - At the Cape Canaveral weather station in Florida, workers carry an upper-level weather balloon outside for release. The release was part of a media tour prior to the launch of Space Shuttle Discovery on mission STS-121 July 1. The radar-tracked balloon detects wind shears that can affect a shuttle launch. At the facility, which is operated by the U.S. Air Force 45th Weather Squadron, media saw the tools used by the weather team to create the forecast for launch day. They received a briefing on how the launch weather forecast is developed by Shuttle Weather Officer Kathy Winters and met the forecasters for the space shuttle and the expendable launch vehicles. Also participating were members of the Applied Meteorology Unit who provide special expertise to the forecasters by analyzing and interpreting unusual or inconsistent weather data. The media were able to see the release of the Rawinsonde weather balloon carrying instruments aloft to be used as part of developing the forecast. Photo credit: NASA/George Shelton

KSC-06pd1280

NASA Image and Video Library

2006-06-28

KENNEDY SPACE CENTER, FLA. - An upper-level weather balloon sails into the sky after release from the Cape Canaveral weather station in Florida. The release was planned as part of a media tour prior to the launch of Space Shuttle Discovery on mission STS-121 July 1. The radar-tracked balloon detects wind shears that can affect a shuttle launch. At the facility, which is operated by the U.S. Air Force 45th Weather Squadron, media saw the tools used by the weather team to create the forecast for launch day. They received a briefing on how the launch weather forecast is developed by Shuttle Weather Officer Kathy Winters and met the forecasters for the space shuttle and the expendable launch vehicles. Also participating were members of the Applied Meteorology Unit who provide special expertise to the forecasters by analyzing and interpreting unusual or inconsistent weather data. The media were able to see the release of the Rawinsonde weather balloon carrying instruments aloft to be used as part of developing the forecast. Photo credit: NASA/George Shelton

KSC-06pd1275

NASA Image and Video Library

2006-06-28

KENNEDY SPACE CENTER, FLA. - At the Cape Canaveral weather station in Florida, a member of the weather team prepares a Rawinsonde weather balloon for release. The release was planned as part of a media tour prior to the launch of Space Shuttle Discovery on mission STS-121 July 1. At the facility, which is operated by the U.S. Air Force 45th Weather Squadron, media saw the tools used by the weather team to create the forecast for launch day. They received a briefing on how the launch weather forecast is developed by Shuttle Weather Officer Kathy Winters and met the forecasters for the space shuttle and the expendable launch vehicles. Also participating were members of the Applied Meteorology Unit who provide special expertise to the forecasters by analyzing and interpreting unusual or inconsistent weather data. The media were able to see the release of the Rawinsonde weather balloon carrying instruments aloft to be used as part of developing the forecast. Photo credit: NASA/George Shelton

TDRS-L Media Day

NASA Image and Video Library

2014-01-03

TITUSVILLE, Fla. – Members of the news media are given an up-close look at the Tracking and Data Relay Satellite, or TDRS-L, spacecraft undergoing preflight processing inside the Astrotech payload processing facility in Titusville. TDRS-L is being prepared for encapsulation inside its payload fairing prior to being transported to Launch Complex 41 at Cape Canaveral Air Force Station. Journalists visited Astrotech as part of TDRS-L Media Day to conduct interviews and photograph the satellite that will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

Mathematical modeling of the infrastructure of attosecond actuators and femtosecond sensors of nonequilibrium physical media in smart materials

NASA Astrophysics Data System (ADS)

Beznosyuk, Sergey A.; Maslova, Olga A.; Zhukovsky, Mark S.; Valeryeva, Ekaterina V.; Terentyeva, Yulia V.

2017-12-01

The task of modeling the multiscale infrastructure of quantum attosecond actuators and femtosecond sensors of nonequilibrium physical media in smart materials is considered. Computer design and calculation of supra-atomic femtosecond sensors of nonequilibrium physical media in materials based on layered graphene-transition metal nanosystems are carried out by vdW-DF and B3LYP methods. It is shown that the molybdenum substrate provides fixation of graphene nanosheets by Van der Waals forces at a considerable distance (5.3 Å) from the metal surface. This minimizes the effect of the electronic and nuclear subsystem of the substrate metal on the sensory properties of "pure" graphene. The conclusion is substantiated that graphene-molybdenum nanosensors are able to accurately orient and position one molecule of carbon monoxide. It is shown that graphene selectively adsorbs CO and fixes the oxygen atom of the molecule at the position of the center of the graphene ring C6.

Isolation of nanoscale exosomes using viscoelastic effect

NASA Astrophysics Data System (ADS)

Hu, Guoqing; Liu, Chao

2017-11-01

Exosomes, molecular cargos secreted by almost all mammalian cells, are considered as promising biomarkers to identify many diseases including cancers. However, the small size of exosomes (30-200 nm) poses serious challenges on their isolation from the complex media containing a variety of extracellular vesicles (EVs) of different sizes, especially in small sample volumes. Here we develop a viscoelasticity-based microfluidic system to directly separate exosomes from cell culture media or serum in a continuous, size-dependent, and label-free manner. Using a small amount of biocompatible polymer as the additive into the media to control the viscoelastic forces exerted on EVs, we are able to achieve a high separation purity (>90%) and recovery (>80%) of exosomes. The size cutoff in viscoelasticity-based microfluidics can be easily controlled using different PEO concentrations. Based on this size-dependent viscoelastic separation strategy, we envision the handling of diverse nanoscale objects, such as gold nanoparticles, DNA origami structures, and quantum dots. This work was supported financially by National Natural Science Foundation of China (11572334, 91543125).

Enhanced electronic excitation energy transfer between dye molecules incorporated in nano-scale media with apparent fractal dimensionality

NASA Astrophysics Data System (ADS)

Yefimova, Svetlana L.; Rekalo, Andrey M.; Gnap, Bogdan A.; Viagin, Oleg G.; Sorokin, Alexander V.; Malyukin, Yuri V.

2014-09-01

In the present study, we analyze the efficiency of Electronic Excitation Energy Transfer (EEET) between two dyes, an energy donor (D) and acceptor (A), concentrated in structurally heterogeneous media (surfactant micelles, liposomes, and porous SiO2 matrices). In all three cases, highly effective EEET in pairs of dyes has been found and cannot be explained by Standard Förster-type theory for homogeneous solutions. Two independent approaches based on the analysis of either the D relative quantum yield () or the D fluorescence decay have been used to study the deviation of experimental results from the theoretical description of EEET process. The observed deviation is quantified by the apparent fractal distribution of molecules parameter . We conclude that the highly effective EEET observed in the nano-scale media under study can be explained by both forced concentration of the hydrophobic dyes within nano-volumes and non-uniform cluster-like character of the distribution of D and A dye molecules within nano-volumes.

Factors in the Introduction of a New Communications Technology Into Syria and Turkey: Background Data.

ERIC Educational Resources Information Center

LeCompte, Gare

Syria and Turkey differ in styles of government and patterns of media use. Syria is governed by a military junta; factionalism, intolerance of opposition, and the lack of any options except the use of force to gain political power, have inhibited political stability. Syrian newspapers have low credibility and are characterized by low standards,…

Culture Clash: U.S. Television Programs in Korea.

ERIC Educational Resources Information Center

Kang, Jong Geun; Morgan, Michael

A study examined the influence that the United States media have on the values, morality, and traditions of other countries, and more specifically the effects on Korean values of American television as it is broadcast on the U.S. Forces Korean Network. College students in Seoul, Korea (46% male and 54% female with a mean age of 24.6) answered a…

Thermocapillary Motion in an Emulsion

NASA Technical Reports Server (NTRS)

Pukhnachov, Vladislav V.; Voinov, Oleg V.

1996-01-01

The phenomenological model for the motion of an emulsion or a gas-liquid mixture exposed to thermocapillary forces and micro-acceleration is formulated. The analytical and numerical investigation of one-dimensional flows for these media is fulfilled, the structure of discontinuous motion is studied. The stability conditions of a space-uniform state and of the interface between an emulsion and a pure liquid are obtained.

Hopes and fears for professional movement in the stem cell community.

PubMed

Longstaff, Holly; Khramova, Vera; Eijkholt, Marleen; Mizgalewicz, Ania; Illes, Judy

2013-05-02

We examine here how the issue of professional migration in stem cell research has been explored in news media, government documents, and the peer-reviewed literature. The results shed light on how patterns of and forces that motivate these movements are depicted and highlight issues of significance to the stem cell community. Copyright © 2013 Elsevier Inc. All rights reserved.

Single-sided lateral-field and phototransistor-based optoelectronic tweezers

NASA Technical Reports Server (NTRS)

Ohta, Aaron (Inventor); Chiou, Pei-Yu (Inventor); Hsu, Hsan-Yin (Inventor); Jamshidi, Arash (Inventor); Wu, Ming-Chiang (Inventor); Neale, Steven L. (Inventor)

2011-01-01

Described herein are single-sided lateral-field optoelectronic tweezers (LOET) devices which use photosensitive electrode arrays to create optically-induced dielectrophoretic forces in an electric field that is parallel to the plane of the device. In addition, phototransistor-based optoelectronic tweezers (PhOET) devices are described that allow for optoelectronic tweezers (OET) operation in high-conductivity physiological buffer and cell culture media.

Sourcebook for Sex Equality: Small Presses. An Annotated Listing of Small Presses and Alternative Sources for Books and Media. Bibliographic Series, 1.

ERIC Educational Resources Information Center

Hulme, Marylin A., Comp.

This briefly annotated guide to non-sexist and non-racist educational materials suppliers includes small presses, non-profit educational firms, women's sections of professional and trade organizations, task forces in State educational departments, and feminist publishers, bookstores and distributors. Aimed at assisting librarians and teachers in…

GRACE-FO Prelaunch Briefing

NASA Image and Video Library

2018-05-21

NASA Headquarters Public Affairs Officer Steve Cole moderates a Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission prelaunch media briefing, Monday, May 21, 2018, at Vandenberg Air Force Base in California. The twin GRACE-FO spacecraft will measure changes in how mass is redistributed within and among Earth's atmosphere, oceans, land and ice sheets, as well as within Earth itself. Photo Credit: (NASA/Bill Ingalls)

33 CFR 334.1450 - Atlantic Ocean off north coast of Puerto Rico; practice firing areas, U.S. Army Forces Antilles.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) The fact that practice firing is to take place over the designated area will be advertised to the public through the usual media for the dissemination of such information. Factual information as to the dates, time, and characteristics of the firing will be advertised in advance of each session of firing...

CO2 flux through a Wyoming seasonal snowpack: Diffusional and pressure pumping effects

Treesearch

William Massman; Richard Sommerfeld; Karl Zeller; Ted Hehn; Laura Hudnell; Shannon Rochelle

1995-01-01

The movement of trace gases through porous media results from a combination of molecular diffusion and natural convection forced by turbulent atmospheric pressure pumping. This study presents observational and modeling results of an experiment to estimate the C02 flux through a seasonal snowpack in the Rocky Mountains of southern Wyoming, USA. Profiles of C02 mole...

Social Media Sites

Science.gov Websites

Training Center Advanced Distributed Learning Service (ADLS) AETC/PACE AF Band of the West AF Civil (Videos) DoD Terms Of Service Agreements GSA Terms Of Service Agreements Air Force Web Posting Assessment 127th Wing 128th Air Refueling Wing 129th Rescue Wing 129th Rescue Wing ANG 12th Flying Training Wing

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Tim Dunn, launch director, NASA’s Launch Services Program, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

A video showing NASA's InSight spacecraft separating from the Atlas V rocket is seen during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Stu Spath, InSight program manager, Lockheed Martin Space, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Andy Klesh, MarCO chief engineer, NASA JPL, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Tom Hoffman, InSight project manager, NASA JPL, right, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Tilman Spohn, HP3 investigation lead, Institute of Planetary Research (DLR), discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Annick Sylvestre-Baron, SEIS deputy project manager, CNES, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Scott Messer, United Launch Alliance program manager for NASA missions, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Bruce Banerdt, InSight principal investigator, NASA JPL, discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

Local Monopoly in the Newspaper Industry: Some Skepticism about Its Economic Inevitability and Governmental Embrace.

ERIC Educational Resources Information Center

Barnett, Stephen R.

This is one of several papers presented at a Federal Trade Commission Symposium on Media Concentration. Local newspaper monopolies exist in over 97% of U. S. cities. However, inevitable economic forces are not the only cause of monopoly as some have suggested. Two other contributors to monopoly have been economic practices by daily newspapers and…

The President’s Identity Theft Task Force: Combating Identity Theft a Strategic Plan

DTIC Science & Technology

2007-04-11

27 a. Safeguarding of Information in the Public Sector ............... 27 b. Responding to Data Breaches in the Public...72 APPENDICES Appendix A: Identity Theft Task Force’s Guidance Memorandum on Data Breach Protocol...government, and the private sector. Consumers, overwhelmed with weekly media reports of data breaches , feel vulnerable and uncertain of how to protect

Dynamic Evaluation of Two Decades of CMAQ Simulations ...

EPA Pesticide Factsheets

This presentation focuses on the dynamic evaluation of the CMAQ model over the continental United States using multi-decadal simulations for the period from 1990 to 2010 to examine how well the changes in observed ozone air quality induced by variations in meteorology and/or emissions are simulated by the model. We applied spectral decomposition of the ozone time-series using the KZ filter to assess the variations in the strengths of synoptic (weather-induced variations) and baseline (long-term variation) forcings, embedded in the simulated and observed concentrations. The results reveal that CMAQ captured the year-to-year variability (more so in the later years than the earlier years) and the synoptic forcing in accordance with what the observations are showing. The National Exposure Research Laboratory (NERL) Computational Exposure Division (CED) develops and evaluates data, decision-support tools, and models to be applied to media-specific or receptor-specific problem areas. CED uses modeling-based approaches to characterize exposures, evaluate fate and transport, and support environmental diagnostics/forensics with input from multiple data sources. It also develops media- and receptor-specific models, process models, and decision support tools for use both within and outside of EPA.

Optics and optronics in university courses for officers of the Federal Armed Forces - special curricula and hands-on lessons vs. academic requirements

NASA Astrophysics Data System (ADS)

Hahlweg, Cornelius; Rothe, Hendrik

2016-09-01

For more than two decades lessons in optics, digital image processing and optronics are compulsory optional subjects and as such integral parts of the courses in mechanical engineering at the University of the Federal Armed Forces in Hamburg. They are provided by the Chair for Measurement and Information Technology. Historically, the curricula started as typical basic lessons in optics and digital image processing and related sensors. Practical sessions originally concentrated on image processing procedures in Pascal, C and later Matlab. They evolved into a broad portfolio of practical hands-on lessons in lab and field, including high-tech and especially military equipment, but also homemaker style primitive experiments, of which the paper will give a methodical overview. A special topic - as always with optics in education - is the introduction to the various levels of abstraction in conjunction with the highly complex and wide-ranging matter squeezed into only two trimesters - instead of semesters at civil universities - for an audience being subject to strains from both study and duty. The talk will be accompanied by striking multi-media material, which will be also part of the multi-media attachment of the paper.

Pressure drop for inertial flows in elastic porous media

NASA Astrophysics Data System (ADS)

Pauthenet, Martin; Bottaro, Alessandro; Davit, Yohan; Quintard, Michel; porous media Team

2017-11-01

The effect of the porosity and of the elastic properties of anisotropic solid skeletons saturated by a fluid is studied for flows displaying unsteady inertial effects. Insight is achieved by direct numerical simulations of the Navier-Stokes equations for model porous media, with inclusions which can oscillate with respect to their reference positions because of the presence of a restoring elastic force modeled by a spring. The numerical technique is based on the immersed boundary method, to easily allow for the displacement of pores of arbitrary shapes and dimensions. Solid contacts are anelastic. The parameters examined include the local Reynolds number, Red , based on the mean velocity through the reference unit cell and the characteristic size of the inclusions, the direction of the macroscopic forcing pressure gradient, the reduced frequency, f*, ratio of the flow frequency to the natural frequency of the spring-mass system, and the reduced mass, m*, ratio of the solid to the fluid density. Results demonstrate the effect of these parameters, and permit to determine the filtration laws useful for the subsequent macroscopic modeling of these flows through the volume averaged Navier-Stokes equations. IDEX Foundation of the University of Toulouse and HPC resources of the CALMIP supercomputing center.

Impulsive movements lead to high hops on sand

NASA Astrophysics Data System (ADS)

Aguilar, Jeffrey; Goldman, Daniel I.

2014-03-01

Various animals exhibit locomotive behaviors (like sprinting and hopping) involving transient bursts of actuation coupled to the ground through internal elastic elements. The performance of such maneuvers is subject to reaction forces on the feet from the environment. On substrates like dry granular media, the laws that govern these forces are not fully understood, and can vary with foot size and shape, material compaction (measured by the volume fraction ϕ) and intrusion kinematics. To gain insight into how such interactions affect jumps on granular media, we study the performance of an actuated spring mass robot. We compare performance between two jump strategies: a single-cycle sine-wave actuation (a ``single jump'') and this actuation preceded by an impulsive preload (a ``preload jump''). We vary ϕ for both strategies, and find that ϕ significantly affects performance: we observe a 200% increase in the single jump height with only a 5% increase in volume fraction using a 7.62 cm diameter flat foot. The preload jump outperforms the single jump height by 150% for all ϕ. We hypothesize that this increase in performance results from higher intrusion velocities and accelerations associated with the preload. NSF POLS CAREER, Burroughs Wellcome Fund, and ARO.

Media and staff in the NASA News Center at Kennedy Space Center

NASA Image and Video Library

2007-06-22

Media and staff in the NASA News Center at Kennedy Space Center applaud the successful landing of Atlantis, visible on the television screens, at NASA's Dryden Flight Research Center at Edwards Air Force Base in California. Returning from mission STS-117, Atlantis touched down on runway 22 at Edwards on orbit 219 after 13 days, 20 hours and 12 minutes in space. The landing was diverted to California due to marginal weather at the Kennedy Space Center. Main gear touchdown was at 3:49:38 p.m. EDT on runway 22. Nose gear touchdown was at 3:49:49 p.m. and wheel stop was at 3:50:48 p.m. This was the 51st landing for the Space Shuttle Program at Edwards Air Force Base. The mission to the International Space Station was a success, installing the S3/S4 truss. The returning crew of seven includes astronaut Sunita Williams, who was flight engineer on the Expedition 15 crew. She achieved a new milestone, a record-setting flight at 194 days, 18 hours and 58 minutes, the longest single spaceflight ever by a female astronaut or cosmonaut.

Los incendios y su salud

EPA Pesticide Factsheets

El humo de los incendios puede tener un efecto adverso en la salud de las personas, especialmente en aquellas que padecen de enfermedades cardíacas y pulmonares. Vea cómo minimizar su exposición al humo.

Separator plugs for liquid helium

NASA Technical Reports Server (NTRS)

Lee, J. M.; Yuan, S. W. K.; Hepler, W. A.; Frederking, T. H. K.

1984-01-01

Work performed during Summer 1984 (from June to Sept. 30) in the area of porous media for use in low temperature applications is discussed. Recent applications are in the area of vapor - liquid phase separation, pumping based on the fountain effect and related subsystems. Areas of potential applications of the latter are outlined in supplementary work. Experimental data have been developed. The linear equations of the two-fluid model are inspected critically in the light of forced convection evidence reported recently. It is emphasized that the Darcy permeability is a unique throughput quantity in the porous media application areas whose use will permit meaningful comparisons of data not only in one lab but also within a group of labs doing porous plug studies.

The social determinants of substance abuse in African American baby boomers: effects of family, media images, and environment.

PubMed

Pope, Robert C; Wallhagen, Margaret; Davis, Harvey

2010-07-01

Grounded theory methodology was used to explore the social processes involved in the use of illicit drugs in older African Americans as an underpinning to the development of approaches to nursing care and treatment. Interviews were conducted with six older African American substance users who were currently in drug treatment programs. Responses to the questions were recorded, transcribed, and analyzed using constant comparative methods. Three core themes emerged: (a) family, (b) media images, and (c) environment. The core issues of substance abuse, such as the environment and larger societal forces, cannot be addressed by one discipline and mandate that clinicians move to an interdisciplinary approach to achieve a plan of care for this growing population.

Interaction of pressure and momentum driven flows with thin porous media: Experiments and modeling

NASA Astrophysics Data System (ADS)

Naaktgeboren, Christian

Flow interaction with thin porous media arise in a variety of natural and man-made settings. Examples include flow through thin grids in electronics cooling, and NOx emissions reduction by means of ammonia injection grids, pulsatile aquatic propulsion with complex trailing anatomy (e.g., jellyfish with tentacles) and microbursts from thunderstorm activity over dense vegetation, unsteady combustion in or near porous materials, pulsatile jet-drying of textiles, and pulsed jet agitation of clothing for trace contaminant sampling. Two types of interactions with thin porous media are considered: (i) forced convection or pressure-driven flows, where fluid advection is maintained by external forces, and (ii) inertial or momentum-driven flows, in which fluid motion is generated but not maintained by external forces. Forced convection analysis through thin permeable media using a porous continuum approach requires the knowledge of porous medium permeability and form coefficients, K and C, respectively, which are defined by the Hazen-Dupuit-Darcy (HDD) equation. Their determination, however, requires the measurement of the pressure-drop per unit of porous medium length. The pressure-drop caused by fluid entering and exiting the porous medium, however, is not related to the porous medium length. Hence, for situations in which the inlet and outlet pressure-drops are not negligible, e.g., for short porous media, the definition of Kand C via the HDD equation becomes ambiguous. This aspect is investigated analytically and numerically using the flow through a restriction in circular pipe and parallel plates channels as preliminary models. Results show that inlet and outlet pressure-drop effects become increasingly important when the inlet and outlet fluid surface fraction φ decreases and the Reynolds number Re increases for both laminar and turbulent flow regimes. A conservative estimate of the minimum porous medium length beyond which the core pressure-drop predominates over the inlet and outlet pressure-drop is obtained by considering a least restrictive porous medium core. Finally, modified K and C are proposed and predictive equations, accurate to within 2.5%, are obtained for both channel configurations with Re ranging from 10-2 to 102 and φ from 6% to 95%. When momentum driven flows interact with thin porous media, the interaction of vortices with the media's complex structure gives way to a number of phenomena of fundamental and applied interest, such as unsteady flow separation. A special case that embodies many of the key features of these flows is the interaction of a vortex ring with a permeable flat surface. Although fundamental, this complex flow configuration has never been considered. The present investigation experimentally studies the fluid mechanics of the interaction of a vortex ring impinging directly on thin permeable flat targets. The vortex ring is formed in water using a piston-cylinder mechanism and visualized using planar laser-induced fluorescence (PLIF). The rings are formed for jet Reynolds numbers of 3000 and 6000, and piston stroke-to-diameter ratios of 1.0, 3.0, and 6.0. Thin screens of similar geometry having surface opening fractions of 44, 60, 69, and 79% are targeted by the rings. The flow that emerges downstream of the screens reforms into a new, "transmitted" vortex ring. For the lower porosity targets, features that are characteristic of vortex ring impingement on walls are also observed, such as primary vortex ring rebound and reversal, flow separation, formation of secondary vortices and mixing. As the interaction proceeds, however, the primary vortex ring and secondary vortices are drawn toward the symmetry axis of the flow by fluid passing through the permeable screen. Quantitative flow measurements using digital particle image velocimetry (DPIV), indicate the transmitted vortex ring has lower velocity and less (total) kinetic energy than the incident ring. Ring trajectories and total kinetic energy relationships between vortices upstream and downstream the porous targets as a function of the porosity are presented, based on the velocity field from the DPIV measurements. Results show that kinetic energy dissipation is more intense for the low porosity targets and that flows with higher initial kinetic energy impacting on the same target loose a smaller percentage of their initial energy.

Numerical Investigation of the Turbulent Wind Flow Through Elevated Windbreak

NASA Astrophysics Data System (ADS)

Agarwal, Ashish; Irtaza, Hassan

2018-06-01

Analysis of airflow through elevated windbreaks is presented in this paper. Permeable nets and impermeable film increases considerable wind forces on the windbreaks which is susceptible to damage during high wind. A comprehensive numerical investigation has been carried out to analyze the effects of wind on standalone elevated windbreak clad with various permeable nets and an impermeable film. The variation of airflow behavior around and through permeable nets and airflow behavior around impermeable film were also been investigated. Computational fluid dynamics techniques using Reynolds Averaged Navier-Stokes equations has been used to predict the wind force coefficient and thus wind forces on panels supporting permeable nets and impermeable film for turbulent wind flow. Elevated windbreak panels were analyzed for seven different permeable nets having various solidity ratio, specific permeability and aerodynamic resistant coefficients. The permeable nets were modelled as porous jump media obeying Forchheimer's law and an impermeable film modelled as rigid wall.

Removing systematic errors in interionic potentials of mean force computed in molecular simulations using reaction-field-based electrostatics

PubMed Central

Baumketner, Andrij

2009-01-01

The performance of reaction-field methods to treat electrostatic interactions is tested in simulations of ions solvated in water. The potential of mean force between sodium chloride pair of ions and between side chains of lysine and aspartate are computed using umbrella sampling and molecular dynamics simulations. It is found that in comparison with lattice sum calculations, the charge-group-based approaches to reaction-field treatments produce a large error in the association energy of the ions that exhibits strong systematic dependence on the size of the simulation box. The atom-based implementation of the reaction field is seen to (i) improve the overall quality of the potential of mean force and (ii) remove the dependence on the size of the simulation box. It is suggested that the atom-based truncation be used in reaction-field simulations of mixed media. PMID:19292522

Micro-rheology on (polymer-grafted) colloids using optical tweezers.

PubMed

Gutsche, C; Elmahdy, M M; Kegler, K; Semenov, I; Stangner, T; Otto, O; Ueberschär, O; Keyser, U F; Krueger, M; Rauscher, M; Weeber, R; Harting, J; Kim, Y W; Lobaskin, V; Netz, R R; Kremer, F

2011-05-11

Optical tweezers are experimental tools with extraordinary resolution in positioning (± 1 nm) a micron-sized colloid and in the measurement of forces (± 50 fN) acting on it-without any mechanical contact. This enables one to carry out a multitude of novel experiments in nano- and microfluidics, of which the following will be presented in this review: (i) forces within single pairs of colloids in media of varying concentration and valency of the surrounding ionic solution, (ii) measurements of the electrophoretic mobility of single colloids in different solvents (concentration, valency of the ionic solution and pH), (iii) similar experiments as in (i) with DNA-grafted colloids, (iv) the nonlinear response of single DNA-grafted colloids in shear flow and (v) the drag force on single colloids pulled through a polymer solution. The experiments will be described in detail and their analysis discussed.

KSC-2011-7550

NASA Image and Video Library

2011-10-26

VANDENBERG AIR FORCE BASE, Calif. -- Participants in the prelaunch news conference at Vandenberg Air Force Base, Calif., for NASA’s National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) spacecraft prepare to address members of the news media gathered at Vandenberg Air Force Base, Calif. NPP represents a critical first step in building the next-generation of Earth-observing satellites. NPP will carry the first of the new sensors developed for this satellite fleet, now known as the Joint Polar Satellite System (JPSS), to be launched in 2016. NPP is the bridge between NASA's Earth Observing System (EOS) satellites and the forthcoming series of JPSS satellites. The mission will test key technologies and instruments for the JPSS missions. NPP is targeted to launch Oct. 28 from Space Launch Complex-2 aboard a United Launch Alliance Delta II rocket. For more information, visit http://www.nasa.gov/NPP. Photo credit: NASA/VAFB

Numerical Investigation of the Turbulent Wind Flow Through Elevated Windbreak

NASA Astrophysics Data System (ADS)

Agarwal, Ashish; Irtaza, Hassan

2018-04-01

Analysis of airflow through elevated windbreaks is presented in this paper. Permeable nets and impermeable film increases considerable wind forces on the windbreaks which is susceptible to damage during high wind. A comprehensive numerical investigation has been carried out to analyze the effects of wind on standalone elevated windbreak clad with various permeable nets and an impermeable film. The variation of airflow behavior around and through permeable nets and airflow behavior around impermeable film were also been investigated. Computational fluid dynamics techniques using Reynolds Averaged Navier-Stokes equations has been used to predict the wind force coefficient and thus wind forces on panels supporting permeable nets and impermeable film for turbulent wind flow. Elevated windbreak panels were analyzed for seven different permeable nets having various solidity ratio, specific permeability and aerodynamic resistant coefficients. The permeable nets were modelled as porous jump media obeying Forchheimer's law and an impermeable film modelled as rigid wall.

Electromagnetic Characterization of Inhomogeneous Media

DTIC Science & Technology

2012-03-22

Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command In Partial Fulfillment of the Requirements...found in the laboratory data, fun is the code that contains the theatrical formulation of S11, and beta0 is the initial constitutive parameter estimate...collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources

The Evidence in Hand: Report of the Task Force on the Artifact in Library Collections. Optimizing Collections and Services for Scholarly Use.

ERIC Educational Resources Information Center

Nichols, Stephen G.; Smith, Abby

This report discusses the ways in which artifacts and their physical frailties affect their research value--originality, faithfulness, fixity, and stability--over time and how libraries can minimize the risk of unacceptable loss of that value. It investigates the specific issues around selected media, such as paper-based printed matter, moving…

Air Force Space Command. Space and Missile Systems Center Standard. Configuration Management

DTIC Science & Technology

2008-06-13

Aerospace Corporation report number TOR-2006( 8583 )-1. 3. Beneficial comments (recommendations, additions, deletions) and any pertinent data that...Engineering Drawing Practices IEEE STD 610.12 Glossary of Software Engineering Terminology, September 28,1990 ISO /IEC 12207 Software Life...item, regardless of media, formally designated and fixed at a specific time during the configuration item’s life cycle. (Source: ISO /IEC 12207

Physical optics in a uniform gravitational field

NASA Astrophysics Data System (ADS)

Hacyan, Shahen

2012-01-01

The motion of a (quasi-)plane wave in a uniform gravitational field is studied. It is shown that the energy of an elliptically polarized wave does not propagate along a geodesic, but in a direction that is rotated with respect to the gravitational force. The similarity with the walk-off effect in anisotropic crystals or the optical Magnus effect in inhomogeneous media is pointed out.

InSight Prelaunch

NASA Image and Video Library

2018-05-04

NASA social media attendees pose for a group photograph in front of the United Launch Alliance (ULA) Atlas-V rocket with NASA's InSight spacecraft onboard, Friday, May 4, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

Using Automated Network Detection & Response to Visualize Malicious IT

Science.gov Websites

answer. So I'm going to target talking for about 40 minutes, and leave some time left over for question forced operators to switch to manual mode. The media at the time reported on it, and determined that a available online. I would encourage you, if you have not read it, to please take time to read this and to

Being Poor, Black, and American: The Impact of Political, Economic, and Cultural Forces

ERIC Educational Resources Information Center

Wilson, William Julius

2011-01-01

Through the second half of the 1990s and into the early years of the 21st century, public attention to the plight of poor black Americans seemed to wane. There was scant media attention to the problem of concentrated urban poverty (neighborhoods in which a high percentage of the residents fall beneath the federally designated poverty line), little…

Classifying Particles By Acoustic Levitation

NASA Technical Reports Server (NTRS)

Barmatz, Martin B.; Stoneburner, James D.

1983-01-01

Separation technique well suited to material processing. Apparatus with rectangular-cross-section chamber used to measure equilibrium positions of low-density spheres in gravitational field. Vertical acoustic forces generated by two opposing compression drivers exciting fundamental plane-wave mode at 1.2 kHz. Additional horizontal drivers centered samples along vertical axis. Applications in fusion-target separation, biological separation, and manufacturing processes in liquid or gas media.

Plastic Media Blasting Data Gathering Study

DTIC Science & Technology

1986-12-01

products of organic compounds containing the amino group (-NH 2 ) and an aldehyde. The better known members of this group are urea formaldehyde (a...suspected carcinogen) and melamine formaldehyde . The actual composition and toxicity of the dust from the various operations must be collected and...blasting is a paint removal technique in which small, granular amino thermoset or unsaturated polyester resins (plastic beads) are forced at high

InSight Prelaunch Briefing

NASA Image and Video Library

2018-05-03

Philippe Lognonné, SEIS investigation lead, Institut de Physique du Globe de Paris (IPGP) discusses NASA's InSight mission during a prelaunch media briefing, Thursday, May 3, 2018, at Vandenberg Air Force Base in California. InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is a Mars lander designed to study the "inner space" of Mars: its crust, mantle, and core. Photo Credit: (NASA/Bill Ingalls)

An Integrated Approach to the Teaching and Learning of Science and Mathematics Utilising Technology--The Teachers' Perspective

ERIC Educational Resources Information Center

Johnston, Jennifer; Riordain, Maire Ni; Walshe, Grainne

2014-01-01

The concept and importance of curriculum integration in Science and Mathematics has come to the fore in the recent years (Czerniak, 2007). Ireland's Science and Mathematics performance is well documented and extensively reported in the media and elsewhere (e.g. Expert Group on Future Skills Needs, 2008; Task Force on the Physical Sciences, 2002).…

Three Essays on Terrorism, its Relationship with Natural Disasters, and its Effect on Female Labor Force Participation

DTIC Science & Technology

2011-09-01

civilian, non- government organizations, private citizens and property, religious figures and institutions, tourists , transportation, and utilities...media, maritime – civilian, non- government organizations, private citizens and property, religious figures and institutions, tourists , transportation... government . A society vests much of its security within its government ?s ability to protect; thus, the effectiveness and efficiency of disaster preparedness