WorldWideScience

Sample records for twentieth nasa propagation

  1. Proceedings of the Seventeenth NASA Propagation Experimenters Meeting (NAPEX 17) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

    Science.gov (United States)

    Davarian, Faramaz (Editor)

    1993-01-01

    The NASA Propagation Experimenters Meeting (NAPEX) is convened annually to discuss studies made on radio wave propagation by investors from domestic and international organizations. NAPEX 17 was held on 15 June 1993. The meeting was organized into two technical sessions. The first session was dedicated to slant path propagation studies and experiments. The second session focused on propagation studies for mobile and personal communications. Preceding NAPEX 17, the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop was held on 14 June 1993 to review ACTS propagation activities with emphasis on ACTS experiments status and data collection, processing, and exchange.

  2. NASA Perspective and Modeling of Thermal Runaway Propagation Mitigation in Aerospace Batteries

    Science.gov (United States)

    Shack, P.; Iannello, C.; Rickman, S.; Button, R.

    2014-01-01

    NASA has traditionally sought to reduce the likelihood of a single cell thermal runaway (TR) in their aerospace batteries to an absolute minimum by employing rigorous screening program of the cells. There was generally a belief that TR propagation resulting in catastrophic failure of the battery was a forgone conclusion for densely packed aerospace lithium-ion batteries. As it turns out, this may not be the case. An increasing number of purportedly TR propagation-resistant batteries are appearing among NASA partners in the commercial sector and the Department of Defense. In the recent update of the battery safety standard (JSC 20793) to address this paradigm shift, the NASA community included requirements for assessing TR severity and identifying simple, low-cost severity reduction measures. Unfortunately, there are no best-practice guidelines for this work in the Agency, so the first project team attempting to meet these requirements would have an undue burden placed upon them. A NASA engineering Safety Center (NESC) team set out to perform pathfinding activities for meeting those requirements. This presentation will provide contextual background to this effort, as well as initial results in attempting to model and simulate TR heat transfer and propagation within battery designs.

  3. Proposal for a Joint NASA/KSAT Ka-band RF Propagation Terminal at Svalbard, Norway

    Science.gov (United States)

    Volosin, Jeffrey; Acosta, Roberto; Nessel, James; McCarthy, Kevin; Caroglanian, Armen

    2010-01-01

    This slide presentation discusses the placement of a Ka-band RF Propagation Terminal at Svalbard, Norway. The Near Earth Network (NEN) station would be managed by Kongsberg Satellite Services (KSAT) and would benefit NASA and KSAT. There are details of the proposed NASA/KSAT campaign, and the responsibilities each would agree to. There are several reasons for the placement, a primary reason is comparison with the Alaska site, Based on climatological similarities/differences with Alaska, Svalbard site expected to have good radiometer/beacon agreement approximately 99% of time.

  4. Preliminary Results of the NASA Beacon Receiver for Alphasat Aldo Paraboni TDP5 Propagation Experiment

    Science.gov (United States)

    Nessel, James; Morse, Jacquelynne; Zemba, Michael; Riva, Carlo; Luini, Lorenzo

    2014-01-01

    NASA Glenn Research Center (GRC) and the Politecnico di Milano (POLIMI) have initiated a joint propagation campaign within the framework of the Alphasat propagation experiment to characterize rain attenuation, scintillation, and gaseous absorption effects of the atmosphere in the 40 GHz band. NASA GRC has developed and installed a K/Q-band (20/40 GHz) beacon receiver at the POLIMI campus in Milan, Italy, which receives the 20/40 GHz signals broadcast from the Alphasat Aldo Paraboni TDP#5 beacon payload. The primary goal of these measurements is to develop a physical model to improve predictions of communications systems performance within the Q-band. Herein, we describe the design and preliminary performance of the NASA propagation terminal, which has been installed and operating in Milan since May 2014. The receiver is based upon a validated Fast Fourier Transform (FFT) I/Q digital design approach utilized in other operational NASA propagation terminals, but has been modified to employ power measurement via a frequency estimation technique and to coherently track and measure the amplitude of the 20/40 GHz beacon signals. The system consists of a 1.2-m K-band and a 0.6-m Qband Cassegrain reflector employing synchronous open-loop tracking to track the inclined orbit of the Alphasat satellite. An 8 Hz sampling rate is implemented to characterize scintillation effects, with a 1-Hz measurement bandwidth dynamic range of 45 dB. A weather station with an optical disdrometer is also installed to characterize rain drop size distribution for correlation with physical based models.

  5. Performance of the NASA Beacon Receiver for the Alphasat Aldo Paraboni TDP5 Propagation Experiment

    Science.gov (United States)

    Nessel, James; Morse, Jacquelynne; Zemba, Michael; Riva, Carlo; Luini, Lorenzo

    2015-01-01

    NASA Glenn Research Center (GRC) and the Politecnico di Milano (POLIMI) have initiated a joint propagation campaign within the framework of the Alphasat propagation experiment to characterize rain attenuation, scintillation, and gaseous absorption effects of the atmosphere in the 40 gigahertz band. NASA GRC has developed and installed a K/Q-band (20/40 gigahertz) beacon receiver at the POLIMI campus in Milan, Italy, which receives the 20/40 gigahertz signals broadcast from the Alphasat Aldo Paraboni Technology Demonstration Payload (TDP) no. 5 beacon payload. The primary goal of these measurements is to develop a physical model to improve predictions of communications systems performance within the Q-band. Herein, we describe the design and preliminary performance of the NASA propagation terminal, which has been installed and operating in Milan since June 2014. The receiver is based upon a validated Fast Fourier Transform (FFT) I/Q digital design approach utilized in other operational NASA propagation terminals, but has been modified to employ power measurement via a frequency estimation technique and to coherently track and measure the amplitude of the 20/40 gigahertz beacon signals. The system consists of a 1.2-meter K-band and a 0.6-meter Q-band Cassegrain reflector employing synchronous open-loop tracking to track the inclined orbit of the Alphasat satellite. An 8 hertz sampling rate is implemented to characterize scintillation effects, with a 1-hertz measurement bandwidth dynamic range of 45 decibels. A weather station with an optical disdrometer is also installed to characterize rain drop size distribution for correlation with physical based models.

  6. NASA-STD-6001B Test 1 Upward Flame Propagation; Sample Length Impact on MOC Investigation

    Science.gov (United States)

    Harper, Susana Tapia; Juarez, Alfredo; Woods, Brenton L.; Beeson, Harold D.

    2017-01-01

    Understanding the combustion behavior of materials in the elevated oxygen environments of habitable spacecraft is of utmost importance to crew safety and mission success. Currently, certification for unrestricted flight usage of a material with respect to flammability involves passing the Upward Flame Propagation Test of NASA-STD-6001B (Test 1). This test evaluates materials in a standardized test configuration for two failure criteria: self-extinguishment within 15 cm (6 in.) and the propensity of flame propagation by means of flaming material transfer. By the NASA standard, full-length samples are 30 cm (12 in.) in length; however, factors independent of the test method such as limited material availability or various nonstandard test configurations limit the full pretest sample lengths available for test. This paper characterizes the dependence, if any, of pretest sample length on NASA-STD-6001B Test 1 results. Testing was performed using the Maximum Oxygen Concentration (MOC) Threshold Method to obtain a data set for each sample length tested. In addition, various material types, including cloth (Nomex), foam (TA-301) and solids (Ultem), were tested to investigate potential effects of test specimen types. Though additional data needs to be generated to provide statistical confidence, preliminary findings are that use of variable sample lengths has minimal impact on NASA-STD-6001B flammability performance and MOC determination.

  7. System and Propagation Availability Analysis for NASA's Advanced Air Transportation Technologies

    Science.gov (United States)

    Ugweje, Okechukwu C.

    2000-01-01

    This report summarizes the research on the System and Propagation Availability Analysis for NASA's project on Advanced Air Transportation Technologies (AATT). The objectives of the project were to determine the communication systems requirements and architecture, and to investigate the effect of propagation on the transmission of space information. In this report, results from the first year investigation are presented and limitations are highlighted. To study the propagation links, an understanding of the total system architecture is necessary since the links form the major component of the overall architecture. This study was conducted by way of analysis, modeling and simulation on the system communication links. The overall goals was to develop an understanding of the space communication requirements relevant to the AATT project, and then analyze the links taking into consideration system availability under adverse atmospheric weather conditions. This project began with a preliminary study of the end-to-end system architecture by modeling a representative communication system in MATLAB SIMULINK. Based on the defining concepts, the possibility of computer modeling was determined. The investigations continue with the parametric studies of the communication system architecture. These studies were also carried out with SIMULINK modeling and simulation. After a series of modifications, two end-to-end communication links were identified as the most probable models for the communication architecture. Link budget calculations were then performed in MATHCAD and MATLAB for the identified communication scenarios. A remarkable outcome of this project is the development of a graphic user interface (GUI) program for the computation of the link budget parameters in real time. Using this program, one can interactively compute the link budget requirements after supplying a few necessary parameters. It provides a framework for the eventual automation of several computations

  8. Prediction of Broadband Shock-Associated Noise Including Propagation Effects Originating NASA

    Science.gov (United States)

    Miller, Steven; Morris, Philip J.

    2012-01-01

    An acoustic analogy is developed based on the Euler equations for broadband shock-associated noise (BBSAN) that directly incorporates the vector Green s function of the linearized Euler equations and a steady Reynolds-Averaged Navier-Stokes solution (SRANS) to describe the mean flow. The vector Green s function allows the BBSAN propagation through the jet shear layer to be determined. The large-scale coherent turbulence is modeled by two-point second order velocity cross-correlations. Turbulent length and time scales are related to the turbulent kinetic energy and dissipation rate. An adjoint vector Green s function solver is implemented to determine the vector Green s function based on a locally parallel mean flow at different streamwise locations. The newly developed acoustic analogy can be simplified to one that uses the Green s function associated with the Helmholtz equation, which is consistent with a previous formulation by the authors. A large number of predictions are generated using three different nozzles over a wide range of fully-expanded jet Mach numbers and jet stagnation temperatures. These predictions are compared with experimental data from multiple jet noise experimental facilities. In addition, two models for the so-called fine-scale mixing noise are included in the comparisons. Improved BBSAN predictions are obtained relative to other models that do not include propagation effects.

  9. Twentieth Century Moral Philosophy

    OpenAIRE

    Stout, Rowland

    2008-01-01

    Despite being somewhat long in the tooth at the time, Aristotle, Hume and Kant were still dominating twentieth century moral philosophy. Much of the progress made in that century came from a detailed working through of each of their approaches by the expanding and increasingly professionalized corps of academic philosophers. And this progress can be measured not just by the quality and sophistication of moral philosophy at the end of that century, but also by the narrowing of s...

  10. Finite Difference Simulations of Acoustic and Gravity Wave Propagation in Mars Atmosphere: Applications to INSIGHT NASA Mission and Mars Microphone Experiments

    Science.gov (United States)

    Garcia, R.; Brissaud, Q.; Martin, R.; Rolland, L. M.; Komatitsch, D.

    2015-12-01

    A simulation tool of acoustic and gravity wave propagation through finite differences is applied to the case of Mars atmosphere.The details of the code and its validation for Earth atmosphere are presented in session SA003.The simulations include the modeling of both acoustic and gravity waves in the same run, an effects of exponential density decrease, winds and attenuation.The application to Mars requires the inclusion of a specific attenuation effect related to the relaxation induced by vibrational modes of carbon dioxide molecules.Two different applications are presented demonstrating the ability of the simulation tool to work at very different scale length and frequencies.First the propagation of acoustic and gravity waves due to a bolide explosion in the atmosphere of Mars are simulated.This case has a direct application to the atmospheric pressure and seismic measurements that will be performed by INSIGHT NASA discovery mission next year.Then, we also present simulations of sound wave propagation on a scale of meters that can be used to infer the feasability microphone measurements for future Mars missions.

  11. NASA-Langley Research Center's participation in a round-robin comparison between some current crack-propagation prediction methods

    Science.gov (United States)

    Hudson, C. M.; Lewis, P. E.

    1979-01-01

    A round-robin study was conducted which evaluated and compared different methods currently in practice for predicting crack growth in surface-cracked specimens. This report describes the prediction methods used by the Fracture Mechanics Engineering Section, at NASA-Langley Research Center, and presents a comparison between predicted crack growth and crack growth observed in laboratory experiments. For tests at higher stress levels, the correlation between predicted and experimentally determined crack growth was generally quite good. For tests at lower stress levels, the predicted number of cycles to reach a given crack length was consistently higher than the experimentally determined number of cycles. This consistent overestimation of the number of cycles could have resulted from a lack of definition of crack-growth data at low values of the stress intensity range. Generally, the predicted critical flaw sizes were smaller than the experimentally determined critical flaw sizes. This underestimation probably resulted from using plane-strain fracture toughness values to predict failure rather than the more appropriate values based on maximum load.

  12. St. Augustine in Twentieth-Century Music

    DEFF Research Database (Denmark)

    Petersen, Nils Holger

    2012-01-01

    A discussion - in a cultural historical perspective - of primarily two important twentieth-century musical works setting texts by St Augustine: Klaus Huber's Soliloquia Sancti Aurelii Augustini and Michael Tippett's The Vision of Saint Augustine.......A discussion - in a cultural historical perspective - of primarily two important twentieth-century musical works setting texts by St Augustine: Klaus Huber's Soliloquia Sancti Aurelii Augustini and Michael Tippett's The Vision of Saint Augustine....

  13. Symptom removal: the twentieth century experience.

    Science.gov (United States)

    Weitzenhoffer, André M

    2004-01-01

    The twentieth century hypnosis literature regarding the use of direct symptom removal with hypnosis is in strong contrast with that of the nineteenth. It shows much ambivalence about the use of symptom removal. Objections, largely based on conclusions drawn from psychoanalytic theory, led many twentieth century psychotherapists to reject direct symptom removal. However, a certain amount of empirical evidence, scattered through the literature, has accumulated during the twentieth century to support this rejection. The lack of satisfactory twentieth century statistics and of nineteenth century details concerning hypnotic interventions that were used, makes it impossible to satisfactorily account for the discrepancy in experiences of the nineteenth and twentieth centuries. Although therapists did not altogether abandon working directly with symptoms, many opted instead for modifying and manipulating them by suggestion instead of completely removing them, usually allowing the patient to retain a psychodynamically suitable substitute. Here again a lack of adequate statistics prevents one from being able to properly appraise the effectiveness of this approach which has remained the preferred one for a number of therapists.

  14. Black Women Workers in the Twentieth Century.

    Science.gov (United States)

    Newman, Debra Lynn

    1986-01-01

    At the beginning of the twentieth century one-third of black women worked; most did agricultural or domestic work. Gradually as employment benefits increased and anti-discrimination laws were enforced, work opportunities for black women became more varied and better paying. (VM)

  15. Twentieth-Century Art: Issues of Representation.

    Science.gov (United States)

    Springer, Julie

    1990-01-01

    Presents lesson plans designed for secondary students that assess the role of naturalistic representation in twentieth-century art by examining the artwork of four artists: Pablo Picasso, Rene Magritte, David Smith, and Jackson Pollock. Provides background information on each illustration, and outlines discussion and art production activities for…

  16. Rediscovery of Early Twentieth-Century Ecotheology

    OpenAIRE

    Pihkala Panu

    2016-01-01

    In this article, I examine the early history of Christian environmentalism (“ecotheology”) in the twentieth century. I delineate four strands of early ecotheology: agrarian ecotheology; social Christianity; British contributions; and “post-liberal” foundations for later ecotheological movements. I show that ecotheology was a slowly-rising movement, which had notable proponents. I argue that these early ecotheologians are significant for several reasons. First, these writings support the view ...

  17. NASA Thesaurus

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA Thesaurus contains the authorized NASA subject terms used to index and retrieve materials in the NASA Technical Reports Server (NTRS) and the NTRS...

  18. [Twentieth-century Penelopes: popular culture revisited].

    Science.gov (United States)

    Favaro, Cleci Eulalia

    2010-01-01

    During their settlement of the so-called Old Italian Colonies of Rio Grande do Sul, immigrants constructed a set of positive values that were to serve as an emotional support and a means of outside communication. When women immigrants embroidered images and sayings on wall hangings or kitchen towels made of rustic fabric, they helped nourish the dream of a better life, sought by all and achieved by some. The objects crafted by these twentieth-century Penelopes bear witness to a way of doing, thinking, and acting. Local museums and exhibits have fostered the recovery of old-time embroidery techniques and themes; sold at open-air markets and regional festivals, these products represent income for women whose age excludes them from the formal labor market.

  19. Unmarried motherhood in twentieth-century England.

    Science.gov (United States)

    Thane, Pat

    2011-01-01

    This article explores the experiences of unmarried mothers who kept and tried to raise their children between World War One and the end of the twentieth century. It argues that there has not been a simple progression from their experiencing social stigma and ostracism to more enlightened attitudes since the 1970s. Rather there is a great deal that has hitherto been unknown about what the evidence suggests were very diverse experiences and attitudes throughout the period. A major change since the 1970s has been from pervasive secrecy about unmarried motherhood, cohabitation, adultery and similar 'irregular' practices, especially among the middle classes, to greater openness. The article uses a variety of sources, including the records of the National Council for the Unmarried Mother and Her Child (founded in 1918, now One Parent Families), oral histories, contemporary interviews and official and unofficial investigations.

  20. A database for propagation models

    Science.gov (United States)

    Kantak, Anil V.; Suwitra, Krisjani; Le, Choung

    1993-08-01

    The NASA Propagation Program supports academic research that models various propagation phenomena in the space research frequency bands. NASA supports such research via school and institutions prominent in the field. The products of such efforts are particularly useful for researchers in the field of propagation phenomena and telecommunications systems engineers. The systems engineer usually needs a few propagation parameter values for a system design. Published literature on the subject, such as the Cunsultative Committee for International Radio (CCIR) publications, may help somewhat, but often times, the parameter values given in such publications use a particular set of conditions which may not quite include the requirements of the system design. The systems engineer must resort to programming the propagation phenomena model of interest and to obtain the parameter values to be used in the project. Furthermore, the researcher in the propagation field must then program the propagation models either to substantiate the model or to generate a new model. The researcher or the systems engineer must either be a skillful computer programmer or hire a programmer, which of course increases the cost of the effort. An increase in cost due to the inevitable programming effort may seem particularly inappropriate if the data generated by the experiment is to be used to substantiate the already well-established models, or a slight variation thereof. To help researchers and the systems engineers, it was recommended by the participants of NASA Propagation Experimenters (NAPEX) 15 held in London, Ontario, Canada on 28-29 June 1991, that propagation software should be constructed which will contain models and prediction methods of most propagation phenomenon. Moreover, the software should be flexible enough for the user to make slight changes to the models without expending a substantial effort in programming.

  1. Gear Crack Propagation Investigation

    Science.gov (United States)

    1995-01-01

    Reduced weight is a major design goal in aircraft power transmissions. Some gear designs incorporate thin rims to help meet this goal. Thin rims, however, may lead to bending fatigue cracks. These cracks may propagate through a gear tooth or into the gear rim. A crack that propagates through a tooth would probably not be catastrophic, and ample warning of a failure could be possible. On the other hand, a crack that propagates through the rim would be catastrophic. Such cracks could lead to disengagement of a rotor or propeller from an engine, loss of an aircraft, and fatalities. To help create and validate tools for the gear designer, the NASA Lewis Research Center performed in-house analytical and experimental studies to investigate the effect of rim thickness on gear-tooth crack propagation. Our goal was to determine whether cracks grew through gear teeth (benign failure mode) or through gear rims (catastrophic failure mode) for various rim thicknesses. In addition, we investigated the effect of rim thickness on crack propagation life. A finite-element-based computer program simulated gear-tooth crack propagation. The analysis used principles of linear elastic fracture mechanics, and quarter-point, triangular elements were used at the crack tip to represent the stress singularity. The program had an automated crack propagation option in which cracks were grown numerically via an automated remeshing scheme. Crack-tip stress-intensity factors were estimated to determine crack-propagation direction. Also, various fatigue crack growth models were used to estimate crack-propagation life. Experiments were performed in Lewis' Spur Gear Fatigue Rig to validate predicted crack propagation results. Gears with various backup ratios were tested to validate crack-path predictions. Also, test gears were installed with special crack-propagation gages in the tooth fillet region to measure bending-fatigue crack growth. From both predictions and tests, gears with backup ratios

  2. Twentieth workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    1995-01-26

    PREFACE The Twentieth Workshop on Geothermal Reservoir Engineering, dedicated to the memory of Professor Hank Ramey, was held at Stanford University on January 24-26, 1995. There were ninety-five registered participants. Participants came from six foreign countries: Japan, Mexico, England, Italy, New Zealand and Iceland. The performance of many geothermal reservoirs outside the United States was described in several of the papers. Professor Roland N. Horne opened the meeting and welcomed visitors to the campus. The key note speaker was Marshall Reed, who gave a brief overview of the Department of Energy's current plan. Thirty-two papers were presented in the technical sessions of the workshop. Technical papers were organized into eleven sessions concerning: field development, modeling, well tesubore, injection, geoscience, geochemistry and field operations. Session chairmen were major contributors to the workshop, and we thank: Ben Barker, Bob Fournier, Mark Walters, John Counsil, Marcelo Lippmann, Keshav Goyal, Joel Renner and Mike Shook. In addition to the technical sessions, a panel discussion was held on ''What have we learned in 20 years?'' Panel speakers included Patrick Muffler, George Frye, Alfred Truesdell and John Pritchett. The subject was further discussed by Subir Sanyal, who gave the post-dinner speech at the banquet. The Workshop was organized by the Stanford Geothermal Program faculty, staff, and graduate students. We wish to thank our students who operated the audiovisual equipment. Shaun D. Fitzgerald Program Manager

  3. Exhibition: Linus Pauling and the Twentieth Century

    CERN Document Server

    2003-01-01

    On April 28 the exhibit Linus Pauling and the Twentieth Century organised by UNIDIR (United Nations Institute for Disarmament Research) and SGI (Soka Gakkai International) as well as with the contributions of CERN and the University of Geneva, opened at the United Nations Office of Geneva. Linus Pauling is the only person to date to have won two unshared Nobel Prizes: Chemistry in 1954 and Peace in 1962. The first was awarded for his landmark research on the nature of the chemical bond and its application in understanding the structure of complex substances. The second one acknowledged his courageous protest against atmospheric nuclear testing and his championship of international peace. The exhibit, for audience of all ages, traces seven decades of Linus Pauling's life and influence on the 20th century. Before starting its European tour at the UNESCO headquarters in Paris, the exhibit opened in 1998 in San Francisco and then travelled within the United-States and to Japan with an attendance of more than one...

  4. Exhibition: Linus Pauling and the Twentieth Century

    CERN Multimedia

    2003-01-01

    On April 28 the exhibit Linus Pauling and the Twentieth Century organised by UNIDIR (United Nations Institute for Disarmament Research) and SGI (Soka Gakkai International) as well as with the contributions of CERN and the University of Geneva, opens at the United Nations Office of Geneva. Linus Pauling is the only person to date to have won two unshared Nobel Prizes: Chemistry in 1954 and Peace in 1962. The first was awarded for his landmark research on the nature of the chemical bond and its application in understanding the structure of complex substances. The second one acknowledged his courageous protest against atmospheric nuclear testing and his championship of international peace. The exhibit, for all ages' audiences, traces seven decades of Linus Pauling's life and influence on the 20th century. Before starting its European tour at the UNESCO headquarters in Paris, the exhibit opened in 1998 in San Francisco and then travelled within the United-States and to Japan with an attendance of more than one m...

  5. Redrawing the map: science in twentieth-century China.

    Science.gov (United States)

    Fan, Fa-ti

    2007-09-01

    This essay argues that science in twentieth-century China is a rich topic that can be productively integrated into research and teaching on the history of modern science. It identifies major issues of science in twentieth-century China and demonstrates that they can prove useful to any scholar who wishes to consider science in a comparative and trans/international context. The essay suggests two important steps for a fruitful investigation into the topic of science in twentieth-century China: first, revising the historiographic assumptions and categories that underlie much of the conventional historical narrative of modern science; and, second, breaking free from the tunnel history of national science. To illustrate these points, the essay examines a series of case studies of science in modern China and discusses the relevance of such subjects as scientific nationalism, Maoist mass science, and transnational scientific networks for the understanding of science in the twentieth-century world.

  6. NASA Network

    Science.gov (United States)

    Carter, David; Wetzel, Scott

    2000-01-01

    The NASA Network includes nine NASA operated and partner operated stations covering North America, the west coast of South America, the Pacific, and Western Australia . A new station is presently being setup in South Africa and discussions are underway to add another station in Argentina. NASA SLR operations are supported by Honeywell Technical Solutions, Inc (HTSI), formally AlliedSignal Technical Services, The University of Texas, the University of Hawaii and Universidad Nacional de San Agustin.

  7. Innovation @ NASA

    Science.gov (United States)

    Roman, Juan A.

    2014-01-01

    This presentation provides an overview of the activities National Aeronautics and Space Administration (NASA) is doing to encourage innovation across the agency. All information provided is available publicly.

  8. Imagining the Twentieth Century: Retrospective, Myth, and the Colonial Question

    Directory of Open Access Journals (Sweden)

    David B MacDonald

    2007-01-01

    Full Text Available Retrospectives on the twentieth century often portray it as the most atrocious century in human history, in terms of totalising ideologies, moral abandonment, technological horror, and mass death. The nineteenth and earlier centuries, by contrast, emerge as progressive and enlightened eras, characterised by morality, rationalism, and the absence of war. Creating a dramatic contrast between old and new centuries ignores the historical reality of colonialism and violence outside Europe’s borders. This article problematises twentieth century retrospectives and their nostalgia for the past, comparing these with recent histories of colonialism and genocide. Rather than see the twentieth century as a decisive break from the past, there are important elements of continuity and evolution which should not be ignored.

  9. Stress, Shock, and Adaptation in the Twentieth Century

    DEFF Research Database (Denmark)

    Leese, Peter

    2016-01-01

    Review article on: David Cantor and Edmund Ramsden, eds. Stress, Shock, and Adaptation in the Twentieth Century. Rochester Studies in Medical History. Rochester, N.Y.: University of Rochester Press, 2014. vi + 367 pp. Ill. $125.00 (978-1-58046-476-5).......Review article on: David Cantor and Edmund Ramsden, eds. Stress, Shock, and Adaptation in the Twentieth Century. Rochester Studies in Medical History. Rochester, N.Y.: University of Rochester Press, 2014. vi + 367 pp. Ill. $125.00 (978-1-58046-476-5)....

  10. Mythologies and Panics: Twentieth Century Constructions of Child Prostitution

    Science.gov (United States)

    Brown, Alyson

    2004-01-01

    This paper examines twentieth century social constructions of child prostitutes and child prostitution, the origins of these representations and the extent to which they have been used as metaphors for other perceived social, economic and political problems. It is important to recognise that these children have been sexually abused and that…

  11. Outdoor Physical Education in French Schools during the Twentieth Century

    Science.gov (United States)

    Attali, Michaël; Saint-Martin, Jean

    2017-01-01

    During the twentieth century, outdoor physical education (OPE) gradually integrated with the French education system. Culturally speaking, OPE had to overcome several hurdles because it promoted values such as freedom, initiative and responsibility that were deemed incompatible with the existing educational model. Beyond being a pedagogical tool,…

  12. Mining the Twentieth Century's History from the Time Magazine Corpus

    NARCIS (Netherlands)

    Kestemont, Mike; Karsdorp, F.B.; Düring, Marten

    2014-01-01

    In this paper we report on an explorative study of the history of the twentieth cen- tury from a lexical point of view. As data, we use a diachronic collection of 270,000+ English-language articles har- vested from the electronic archive of the well-known Time Magazine (1923–2006). We attempt to aut

  13. Mythologies and Panics: Twentieth Century Constructions of Child Prostitution

    Science.gov (United States)

    Brown, Alyson

    2004-01-01

    This paper examines twentieth century social constructions of child prostitutes and child prostitution, the origins of these representations and the extent to which they have been used as metaphors for other perceived social, economic and political problems. It is important to recognise that these children have been sexually abused and that…

  14. Wave Propagation

    CERN Document Server

    Ferrarese, Giorgio

    2011-01-01

    Lectures: A. Jeffrey: Lectures on nonlinear wave propagation.- Y. Choquet-Bruhat: Ondes asymptotiques.- G. Boillat: Urti.- Seminars: D. Graffi: Sulla teoria dell'ottica non-lineare.- G. Grioli: Sulla propagazione del calore nei mezzi continui.- T. Manacorda: Onde nei solidi con vincoli interni.- T. Ruggeri: "Entropy principle" and main field for a non linear covariant system.- B. Straughan: Singular surfaces in dipolar materials and possible consequences for continuum mechanics

  15. Neonatal mortality and stillbirths in early twentieth century Derbyshire, England.

    Science.gov (United States)

    Reid, A

    2001-11-01

    Neonatal mortality and stillbirths are recognised to be subject to similar influences, but survival after a successful live birth is usually considered in isolation of foetal wastage. Moreover, individual-level data on age-specific influences and causes of death in a historical context are rare. This paper uses an unusual data set to compare the influences on neonatal mortality and stillbirths in early twentieth century Derbyshire, England. Multivariate hazard and logistic analyses are performed to examine the relative roles of various social, environmental, and demographic factors. The influences on and causal structures of neonatal mortality and stillbirths emerge as broadly similar, with previous reproductive history linked to a considerable amount of variation. The clustering of endogenous deaths was much greater than the clustering of exogenous and post-neonatal deaths, probably reflecting the cause-of-death structure and the relatively healthy social and environmental position of early twentieth century Derbyshire.

  16. Javanese Women and Islam: Identity Formation since the Twentieth Century

    Directory of Open Access Journals (Sweden)

    Kurniawati Hastuti Dewi

    2011-04-01

    Full Text Available Despite the vast research over the last three decades devoted to the lives and social interaction of Javanese women, little has been written on the formation of these women’s identity by focusing on its development from the twentieth century up to the early twenty-first. This paper endeavors to show that the religio-cultural identity of Javanese women was forged through a number of sociocultural circumstances. While revealing different features of the relationship between Javanese women and Islam, I shed light on the role Islam played, particularly since the early twentieth century, in providing transformative power to the role and status of Javanese Muslim women, manifested by the adoption of such Islamic dress codes as veiling, as also an important means of identity politics. I argue that new Islamic discourses have always been born out of the desire to challenge the conservative understanding of the role and status of Javanese women in different historical periods.

  17. Probabilistic reanalysis of twentieth-century sea-level rise

    Science.gov (United States)

    Hay, Carling C.; Morrow, Eric; Kopp, Robert E.; Mitrovica, Jerry X.

    2015-01-01

    Estimating and accounting for twentieth-century global mean sea-level (GMSL) rise is critical to characterizing current and future human-induced sea-level change. Several previous analyses of tide gauge records--employing different methods to accommodate the spatial sparsity and temporal incompleteness of the data and to constrain the geometry of long-term sea-level change--have concluded that GMSL rose over the twentieth century at a mean rate of 1.6 to 1.9 millimetres per year. Efforts to account for this rate by summing estimates of individual contributions from glacier and ice-sheet mass loss, ocean thermal expansion, and changes in land water storage fall significantly short in the period before 1990. The failure to close the budget of GMSL during this period has led to suggestions that several contributions may have been systematically underestimated. However, the extent to which the limitations of tide gauge analyses have affected estimates of the GMSL rate of change is unclear. Here we revisit estimates of twentieth-century GMSL rise using probabilistic techniques and find a rate of GMSL rise from 1901 to 1990 of 1.2 +/- 0.2 millimetres per year (90% confidence interval). Based on individual contributions tabulated in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, this estimate closes the twentieth-century sea-level budget. Our analysis, which combines tide gauge records with physics-based and model-derived geometries of the various contributing signals, also indicates that GMSL rose at a rate of 3.0 +/- 0.7 millimetres per year between 1993 and 2010, consistent with prior estimates from tide gauge records. The increase in rate relative to the 1901-90 trend is accordingly larger than previously thought; this revision may affect some projections of future sea-level rise.

  18. Proceedings of the twentieth LAMPF users group meeting

    Energy Technology Data Exchange (ETDEWEB)

    Marinuzzi, R. (comp.)

    1987-04-01

    The Twentieth Annual LAMPF Users Group Meeting was held October 27-28, 1986, at the Clinton P. Anderson Meson Physics Facility. The program included a number of invited talks on various aspects of nuclear and particle physics as well as status reports on LAMPF and discussions of upgrade options. The LAMPF working groups met and discussed plans for the secondary beam lines, experimental programs, and computing facilities. Individual papers have been cataloged separately.

  19. Mustaches and masculine codes in early twentieth-century America.

    Science.gov (United States)

    Oldstone-Moore, Christopher

    2011-01-01

    The purpose of this article is to deepen our understanding of twentieth-century masculinity by considering the social function of facial hair. The management of facial hair has always been a medium of gendered body language, and as such has elicited a nearly continuous private and public conversation about manliness. Careful attention to this conversation, and to trends in facial hairstyles, illuminates a distinct and consistent pattern of thought about masculinity in early twentieth-century America. The preeminent form of facial hair - mustaches - was used to distinguish between two elemental masculine types: sociable and autonomous. A man was neither wholly one nor the other, but the presence and size of a mustache - or its absence - served to move a man one way or another along the continuum that stretched from one extreme to the other. According to the twentieth-century gender code, a clean-shaven man's virtue was his commitment to his male peers and to local, national or corporate institutions. The mustached man, by contrast, was much more his own man: a patriarch, authority figure or free agent who was able to play by his own rules. Men and women alike read these signals in their evaluation of men.

  20. NASA Astrophysics Technology Needs

    Science.gov (United States)

    Stahl, H. Philip

    2012-01-01

    July 2010, NASA Office of Chief Technologist (OCT) initiated an activity to create and maintain a NASA integrated roadmap for 15 key technology areas which recommend an overall technology investment strategy and prioritize NASA?s technology programs to meet NASA?s strategic goals. Science Instruments, Observatories and Sensor Systems(SIOSS) roadmap addresses technology needs to achieve NASA?s highest priority objectives -- not only for the Science Mission Directorate (SMD), but for all of NASA.

  1. NASA Bioreactor

    Science.gov (United States)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101825 for a version with major elements labeled, and No. 0103180 for an operational schematic. 0101816

  2. NASA Bioreactor

    Science.gov (United States)

    1998-01-01

    Bioreactor Demonstration System (BDS) comprises an electronics module, a gas supply module, and the incubator module housing the rotating wall vessel and its support systems. Nutrient media are pumped through an oxygenator and the culture vessel. The shell rotates at 0.5 rpm while the irner filter typically rotates at 11.5 rpm to produce a gentle flow that ensures removal of waste products as fresh media are infused. Periodically, some spent media are pumped into a waste bag and replaced by fresh media. When the waste bag is filled, an astronaut drains the waste bag and refills the supply bag through ports on the face of the incubator. Pinch valves and a perfusion pump ensure that no media are exposed to moving parts. An Experiment Control Computer controls the Bioreactor, records conditions, and alerts the crew when problems occur. The crew operates the system through a laptop computer displaying graphics designed for easy crew training and operation. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. See No. 0101825 for a version with major elements labeled, and No. 0103180 for an operational schematic. 0101816

  3. NASA Bioreactor

    Science.gov (United States)

    1998-01-01

    Biotechnology Specimen Temperature Controller (BSTC) will cultivate cells until their turn in the bioreactor; it can also be used in culturing experiments that do not require the bioreactor. The BSTC comprises four incubation/refrigeration chambers individually set at 4 to 50 deg. C (near-freezing to above body temperature). Each chamber holds three rugged tissue chamber modules (12 total), clear Teflon bags holding 30 ml of growth media, all positioned by a metal frame. Every 7 to 21 days (depending on growth rates), an astronaut uses a shrouded syringe and the bags' needleless injection ports to transfer a few cells to a fresh media bag, and to introduce a fixative so that the cells may be studied after flight. The design also lets the crew sample the media to measure glucose, gas, and pH levels, and to inspect cells with a microscope. The controller is monitored by the flight crew through a 23-cm (9-inch) color computer display on the face of the BSTC. This view shows the BTSC with the front panel open. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  4. Twentieth century Walker Circulation change: data analysis and model experiments

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Qingjia [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); Chinese Research Academy of Environmental Sciences, River and Coastal Environment Research Center, Beijing (China); Chinese Academy of Sciences, Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Qingdao (China); Latif, Mojib; Park, Wonsun; Keenlyside, Noel S.; Martin, Thomas [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); Semenov, Vladimir A. [Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); A.M. Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences, Moscow (Russian Federation)

    2012-05-15

    Recent studies indicate a weakening of the Walker Circulation during the twentieth century. Here, we present evidence from an atmospheric general circulation model (AGCM) forced by the history of observed sea surface temperature (SST) that the Walker Circulation may have intensified rather than weakened. Observed Equatorial Indo-Pacific Sector SST since 1870 exhibited a zonally asymmetric evolution: While the eastern part of the Equatorial Pacific showed only a weak warming, or even cooling in one SST dataset, the western part and the Equatorial Indian Ocean exhibited a rather strong warming. This has resulted in an increase of the SST gradient between the Maritime Continent and the eastern part of the Equatorial Pacific, one driving force of the Walker Circulation. The ensemble experiments with the AGCM, with and without time-varying external forcing, suggest that the enhancement of the SST gradient drove an anomalous atmospheric circulation, with an enhancement of both Walker and Hadley Circulation. Anomalously strong precipitation is simulated over the Indian Ocean and anomalously weak precipitation over the western Pacific, with corresponding changes in the surface wind pattern. Some sensitivity to the forcing SST, however, is noticed. The analysis of twentieth century integrations with global climate models driven with observed radiative forcing obtained from the Coupled Model Intercomparison Project (CMIP) database support the link between the SST gradient and Walker Circulation strength. Furthermore, control integrations with the CMIP models indicate the existence of strong internal variability on centennial timescales. The results suggest that a radiatively forced signal in the Walker Circulation during the twentieth century may have been too weak to be detectable. (orig.)

  5. Global SST influence on twentieth century NAO variability

    Energy Technology Data Exchange (ETDEWEB)

    Paeth, H.; Hense, A. [Meteorologisches Institut, Universitaet Bonn, 53121 Bonn (Germany); Latif, M. [Max-Planck-Institut fuer Meteorologie, 20146 Hamburg (Germany)

    2003-07-01

    Recent studies have suggested that sea surface temperature (SST) is an important source of variability of the North Atlantic Oscillation (NAO). Here, we deal with four basic aspects contributing to this issue: (1) we investigate the characteristic time scales of this oceanic influence; (2) quantify the scale-dependent hindcast potential of the NAO during the twentieth century as derived from SST-driven atmospheric general circulation model (AGCM) ensembles; (3) the relevant oceanic regions are identified, corresponding SST indices are defined and their relationship to the NAO are evaluated by means of cross spectral analysis and (4) our results are compared with long-term coupled control experiments with different ocean models in order to ensure whether the spectral relationship between the SST regions and the NAO is an intrinsic mode of the coupled climate system, involving the deep ocean circulation, rather than an artefact of the unilateral SST forcing. The observed year-to-year NAO fluctuations are barely influenced by the SST. On the decadal time scales the major swings of the observed NAO are well reproduced by various ensembles from the middle of the twentieth century onward, including the negative state in the 1960s and part of the positive trend afterwards. A six-member ECHAM4-T42 ensemble reveals that the SST boundary condition affects 25% of total decadal-mean and interdecadal-trend NAO variability throughout the twentieth century. The most coherent NAO-related SST feature is the well-known North Atlantic tripole. Additional contributions may arise from the southern Pacific and the low-latitude Indian Ocean. The coupled climate model control runs suggest only the North Atlantic SST-NAO relationship as being a true characteristic of the coupled climate system. The coherence and phase spectra of observations and coupled simulations are in excellent agreement, confirming the robustness of this decadal-scale North Atlantic air-sea coupled mode. (orig.)

  6. The Long Twentieth Century and Barriers to China's Hegemonic Accession

    Directory of Open Access Journals (Sweden)

    John Gulick

    2015-08-01

    Full Text Available Giovanni Arrighi's The Long Twentieth Century is an almost unfathomably ambitious andcomplex work. Its monumentality derives from Arrighi 's conviction that the best way to handicapthe possible futures of the world capitalist geo-economy is to analyze the structural evolution ofthis global system, an evolution spanning more than five centuries; the genius of the work rests inthe distinctive approach that Arrighi takes. At the core of his approach is the identification ofthose long-term trends and accreted characteristics - one might call them "systemiccontradictions" - that promise to send the world capitalist geo-economy in a radically differentdevelopmental direction as US hegemony wanes. Arrighi 's assessment of these contradictionscompel him to make a provocative suggestion: in all likelihood, no singular concentration of stateand economic power possesses the territorial scale or the organizational capacities required tolead the global system through another round of restructuring and expansion. Properly framed,this illuminating insight could serve as the starting point for a theoretical exploration of thesocio-ecological constraints to global capitalist reproduction, but such is a journey (mostly nottaken by Arrighi in The Long Twentieth Century. In fact, to the degree that he subsequentlycontemplates the prospect of a China-centered reconstitution of the world geo-economy, Arrighimarginalizes the question of global systemic contradictions altogether.

  7. Twentieth-Century Leaders in the Moldovan History Textbooks

    Directory of Open Access Journals (Sweden)

    Sergiu Musteata

    2016-06-01

    Full Text Available The main research question of this paper is How the twentieth century leaders are treated in the History textbooks published within the last decade in the Republic of Moldova? The textbooks are a reflection of the History curriculum. Therefore, the analysis starts with the discussion of this document and its content concerning leaders and heroes. The main research sources are the History textbooks published in Moldova during the last decade that debate the events of the twentieth century. The paper analyses how the national, European and world leaders are treated in Moldovan textbooks, and how the discourse and the paradigm get changed depending on political regimes. Based on quantitative and qualitative methods, some conclusions have been made about various leaders, such as Lenin, Stalin, Hitler, Mussolini, Antonescu or leaders from the Cold War era. At the end, the leaders of independent Moldova are briefly presented too. As a result of this analysis we could see how the leaders are presented in the Moldovan textbooks and could conclude that the policy makers, textbook authors and publishers have to pay more attention to this topic.

  8. The NASA Astrophysics Program

    Science.gov (United States)

    Zebulum, Ricardo S.

    2011-01-01

    NASA's scientists are enjoying unprecedented access to astronomy data from space, both from missions launched and operated only by NASA, as well as missions led by other space agencies to which NASA contributed instruments or technology. This paper describes the NASA astrophysics program for the next decade, including NASA's response to the ASTRO2010 Decadal Survey.

  9. Of Sound Mind: Mental Distress and Sound in Twentieth-Century Media Culture

    NARCIS (Netherlands)

    Birdsall, Carolyn; Siewert, Senta

    2013-01-01

    abstractThis article seeks to specify the representation of mental disturbance in sound media during the twentieth century. It engages perspectives on societal and technological change across the twentieth century as crucial for aesthetic strategies developed in radio and sound film production. The

  10. Of Sound Mind: Mental Distress and Sound in Twentieth-Century Media Culture

    NARCIS (Netherlands)

    Birdsall, C.; Siewert, S.

    2013-01-01

    This article seeks to specify the representation of mental disturbance in sound media during the twentieth century. It engages perspectives on societal and technological change across the twentieth century as crucial for aesthetic strategies developed in radio and sound film production. The analysis

  11. Financial crises of the early twentieth century in Ukraine

    Directory of Open Access Journals (Sweden)

    S.Z. Moshenskyi

    2015-12-01

    Full Text Available The article analyzes the major financial crises in Ukraine at early twentieth century dealing with the crises of 1899–1902 and 1908–1910. The main attention is paid to the large-scale crisis of 1899–1902 at the new industrial region in Eastern Ukraine where numerous steel and mining companies based on massive foreign investment (mainly Belgian and French were created shortly. The general boom of new joint-stock companies and insufficient provision of these companies by state orders were the main reason of the crisis which was the reflection of the international industrial and financial crisis of those years. The author also researches the crisis of 1908–1910 in the Ukrainian sugar industry.

  12. John Stewart Bell and twentieth century physics vision and integrity

    CERN Document Server

    Whitaker, Andrew

    2016-01-01

    John Stewart Bell (1928-1990) was one of the most important figures in twentieth-century physics, famous for his work on the fundamental aspects of the century's most important theory, quantum mechanics. While the debate over quantum theory between the supremely famous physicists, Albert Einstein and Niels Bohr, appeared to have become sterile in the 1930s, Bell was able to revive it and to make crucial advances - Bell's Theorem or Bell's Inequalities. He was able to demonstrate a contradiction between quantum theory and essential elements of pre-quantum theory - locality and causality. The book gives a non-mathematical account of Bell's relatively impoverished upbringing in Belfast and his education. It describes his major contributions to quantum theory, but also his important work in the physics of accelerators, and nuclear and elementary particle physics.

  13. Climate of Hungary in the twentieth century according to Feddema

    Science.gov (United States)

    Ács, Ferenc; Breuer, Hajnalka; Skarbit, Nóra

    2015-01-01

    Feddema's (Physical Geography 26:442-466, 2005) bioclimatic classification scheme is applied to Hungary for the twentieth century using the Climatic Research Unit (CRU) data series. The method is tested in two modes. In the first, its original form is used which is suitable for global scale analysis. In the second, the criteria used in the method are slightly modified for mesoscale classification purposes. In both versions, potential evapotranspiration (PET) is calculated using McKenney and Rosenberg's (Meteorol 64:81-110, 1993) formula. We showed that McKenney and Rosenberg's formula could be applied to Hungary. According to Feddema's global scale application, local climates of the three main geographical regions, the Great Hungarian Plain, the North Hungarian Mountains, and Transdanubia, can be distinguished. However, the spatial distribution pattern within the regions is poorly reproduced, if at all. According to Feddema's mesoscale application, a picture of climatic subregions could be observed.

  14. Lost Purity. Social in Nineteenth and Twentieth-century Feminisms

    Directory of Open Access Journals (Sweden)

    Paola Persano

    2016-07-01

    Full Text Available ‘Social Purity’ appears in a part of the French and Anglo-Saxon (Britain and the United States nineteenth-twentieth century’s feminisms, as a mean for many claims: from the full recognition of sexual difference in Hubertine Auclert’s social and ‘differentialist’ republicanism in France to Josephine Butler’s refusal of any purity imposed from above in England, until the absolute turn of the idea of women’s moral superiority and the equal and opposite force to the final exit from ‘the social’ by the American ‘New Womanism’, individualizing and de-feminizing the act of sexual liberation. All this in a continuous play of actions and reactions, sometimes paradoxical, weaving together suffragism and anti-suffragism, contestation of the conjugal complementarity and the never overcome temptations of hetero or self-control.

  15. Remembering and forgetting Freud in early twentieth-century dreams.

    Science.gov (United States)

    Forrester, John

    2006-03-01

    The paper explores the use of Freud's methods of dream interpretation by four English writers of the early twentieth century: T. H. Pear, W. H. R. Rivers, Ernest Jones, and Alix Strachey. Each employed their own dreams in rather different ways: as part of an assessment of Freud's work as a psychological theory, as illustrative of the cogency of Freud's method and theories as part of the psychoanalytic process. Each adopted different approaches to the question of privacy and decorum. The paper argues that assessment of the impact of Freud's work must take account of the application of the method to the researcher's own dreams and the personal impact this process of analysis had upon them, and must also gauge how the dreamers' deployment of Freud's methods influenced their explicit relationship to him and his theories.

  16. Oculoectodermal syndrome: twentieth described case with new manifestations*

    Science.gov (United States)

    Figueiras, Daniela de Almeida; Leal, Deborah Maria de Castro Barbosa; Kozmhinsky, Valter; Querino, Marina Coutinho Domingues; Regueira, Marina Genesia da Silva; Studart, Maria Gabriela de Morais

    2016-01-01

    Oculoectodermal syndrome is a rare disease characterized by the association of aplasia cutis congenita, epibulbar dermoids, and other abnormalities. This report describes the twentieth case of the disease. We report a 4-year-old female child who presented with the classical features of the syndrome: aplasia cutis congenita and epibulbar dermoids. Our case expands the clinical spectrum of the disease to include: diffuse hyperpigmentation (some following the Blaschko´s lines); hypopigmented skin areas on the trunk; arachnoid cyst on the right fronto-parietal border; rounded left side of the hippocampus; and dermoid cyst underlying the bulb-medullary transition. Our patient also reported infantile hemangioma on the right wrist and verrucous hemangioma on the left leg, the latter not previously described in the literature.

  17. Immigration, crime, and incarceration in early twentieth-century America.

    Science.gov (United States)

    Moehling, Carolyn; Piehl, Anne Morrison

    2009-11-01

    The major government commissions on immigration and crime in the early twentieth century relied on evidence that suffered from aggregation bias and the absence of accurate population data, which led them to present partial and sometimes misleading views of the immigrant-native criminality comparison. With improved data and methods, we find that in 1904, prison commitment rates for more serious crimes were quite similar by nativity for all ages except ages 18 and 19, for which the commitment rate for immigrants was higher than for the native-born. By 1930, immigrants were less likely than natives to be committed to prisons at all ages 20 and older, but this advantage disappears when one looks at commitments for violent offenses. The time series pattern reflects a growing gap between natives and immigrants at older ages, one that was driven by sharp increases in the commitment rates of the native-born, while commitment rates for the foreign-born were remarkably stable.

  18. Jung's very twentieth-century view of myth.

    Science.gov (United States)

    Segal, Robert A

    2003-11-01

    It is commonly assumed that Jung's view of myth, like his view of everything else, is best understood vis-à-vis Freud's. I argue that Jung in fact positions himself much more broadly, not merely against other psychologists of myth but more fundamentally against non-psychologists altogether. Undeniably, Jung pits his theory against Freud's, but only after pitting both his theory and Freud's against those theories that assume the subject matter of myth to be the external world rather than the human mind and that assume the function of myth to be either the explanation or the description of the external world rather than the expression of the human mind. The theorists whom Jung challenges are called 'nature mythologists', for whom myth is either a literal explanation or a symbolic description of the natural world. Which element of the natural world myth is about varies from nature mythologist to nature mythologist. The two leading nature mythologists, both of whom Jung cites, were Edward Tylor and James Frazer. Their theories epitomize the nineteenth-century approach to myth. For them, myth is the 'primitive' counterpart to science, which is entirely modern. For them, myth and science are incompatible, science is true and myth false, and myth must therefore go when science comes. Jung's rejection of the external world as the referent of myth and of explanation or description of that world as the function of myth epitomizes the twentieth-century response to nineteenth-century theories. For not merely Jung and Freud but also twentieth-century theorists generally, myth is anything but the 'primitive' counterpart to modern science. Consequently, myth and science are not rivals, so that myth need not go when science comes.

  19. NASA SCaN Overview and Ka-Band Actvities

    Science.gov (United States)

    Stegeman, James D.; Midon, Marco Mario; Davarian, Faramaz; Geldzahler, Barry

    2014-01-01

    The Ka- and Broadband Communications Conference is an international forum attended by worldwide experts in the area of Ka-Band Propagation and satellite communications. Since its inception, NASA has taken the initiative of organizing and leading technical sections on RF Propagation and satellite communications, solidifying its worldwide leadership in the aforementioned areas. Consequently, participation in this conference through the contributions described below will maintain NASA leadership in Ka- and above RF Propagation as it relates to enhancing current and future satellite communication systems supporting space exploration.

  20. Twentieth century ENSO-related precipitation mean states in twentieth century reanalysis, reconstructed precipitation and CMIP5 models

    Science.gov (United States)

    Dai, Ni; Arkin, Phillip A.

    2017-05-01

    El Niño-Southern Oscillation (ENSO)-related precipitation during the entire twentieth century is compared among the twentieth century reanalysis (20CR), a statistically reconstructed precipitation dataset (REC) and 30 Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Empirical orthogonal functions, ENSO-related precipitation composites based on sea surface temperature (SST)-constructed ENSO index and singular value decomposition (SVD) are employed to extract ENSO-related precipitation/SST signals in each dataset. With the background trend being removed in all of the data, our results show that the REC and the 20CR resemble both in their precipitation climatology and ENSO-related precipitation results. The biases in the CMIP5 models precipitation climatology such as dry equator over the Pacific Ocean, "double-intertropical convergence zones (ITCZs)" and overly zonal Southern Pacific convergence zone (SPCZ) are major reasons for lowering spatial correlations with the REC and the 20CR precipitation climatology. Two groups of CMIP5 models are built based on severity of these biases in their precipitation background and the spatial correlations of ENSO-related precipitation with the observations. Compared with the group with more severe biases in its precipitation climatology, the group with smaller biases tends to produce more ENSO-like precipitation patterns, simulate more realistic mean magnitude and seasonal variability of ENSO precipitation signals, as well as generating better ENSO-related SST/precipitation correlation patterns produced in its SVD analysis. The ENSO-related precipitation biases in the CMIP5 models over the western Pacific and Indian Ocean, as well as the equatorial Pacific, are strongly related with their precipitation climatology biases over these regions. The ENSO-related precipitation biases over the off-equator eastern Pacific Ocean are associated with both the "double-ITCZs" biases in the precipitation climatology and the ENSO

  1. Twentieth century ENSO-related precipitation mean states in twentieth century reanalysis, reconstructed precipitation and CMIP5 models

    Science.gov (United States)

    Dai, Ni; Arkin, Phillip A.

    2016-07-01

    El Niño-Southern Oscillation (ENSO)-related precipitation during the entire twentieth century is compared among the twentieth century reanalysis (20CR), a statistically reconstructed precipitation dataset (REC) and 30 Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Empirical orthogonal functions, ENSO-related precipitation composites based on sea surface temperature (SST)-constructed ENSO index and singular value decomposition (SVD) are employed to extract ENSO-related precipitation/SST signals in each dataset. With the background trend being removed in all of the data, our results show that the REC and the 20CR resemble both in their precipitation climatology and ENSO-related precipitation results. The biases in the CMIP5 models precipitation climatology such as dry equator over the Pacific Ocean, "double-intertropical convergence zones (ITCZs)" and overly zonal Southern Pacific convergence zone (SPCZ) are major reasons for lowering spatial correlations with the REC and the 20CR precipitation climatology. Two groups of CMIP5 models are built based on severity of these biases in their precipitation background and the spatial correlations of ENSO-related precipitation with the observations. Compared with the group with more severe biases in its precipitation climatology, the group with smaller biases tends to produce more ENSO-like precipitation patterns, simulate more realistic mean magnitude and seasonal variability of ENSO precipitation signals, as well as generating better ENSO-related SST/precipitation correlation patterns produced in its SVD analysis. The ENSO-related precipitation biases in the CMIP5 models over the western Pacific and Indian Ocean, as well as the equatorial Pacific, are strongly related with their precipitation climatology biases over these regions. The ENSO-related precipitation biases over the off-equator eastern Pacific Ocean are associated with both the "double-ITCZs" biases in the precipitation climatology and the ENSO

  2. Viscothermal wave propagation

    NARCIS (Netherlands)

    Nijhof, Marten Jozef Johannes

    2010-01-01

    In this work, the accuracy, efficiency and range of applicability of various (approximate) models for viscothermal wave propagation are investigated. Models for viscothermal wave propagation describe thewave behavior of fluids including viscous and thermal effects. Cases where viscothermal effects a

  3. Memoirs a twentieth-century journey in science and politics

    CERN Document Server

    Teller, Edward

    2001-01-01

    The story of Edward Teller is the story of the twentieth century. Born in Hungary in 1908, Teller witnessed the rise of Nazism and anti-Semitism, two world wars, the McCarthy era, and the changing face of big science. A brilliant and controversial figure whose work on nuclear weapons was key to the American war effort, Teller has long believed in freedom through strong defense, a philosophy reflected in his stance on arms control and nuclear policy. These extraordinary recollections at last reveal the man behind the headlines-passionate and humorous, devoted and loyal. In clear and compelling prose, Teller tells of the people, events, and ideas that shaped him as a scientist, beginning with his early love of music and math, and continuing with his study of quantum physics with Werner Heisenberg. Present at many of the pivotal moments in modern science, Teller also describes his friendships with some of the century's greatest minds-Einstein, Bohr, Fermi, Szilard, von Neumann, Oppenheimer-and offers an honest a...

  4. Tropospheric circulation during the early twentieth century Arctic warming

    Science.gov (United States)

    Wegmann, Martin; Brönnimann, Stefan; Compo, Gilbert P.

    2016-06-01

    The early twentieth century Arctic warming (ETCAW) between 1920 and 1940 is an exceptional feature of climate variability in the last century. Its warming rate was only recently matched by recent warming in the region. Unlike recent warming largely attributable to anthropogenic radiative forcing, atmospheric warming during the ETCAW was strongest in the mid-troposphere and is believed to be triggered by an exceptional case of natural climate variability. Nevertheless, ultimate mechanisms and causes for the ETCAW are still under discussion. Here we use state of the art multi-member global circulation models, reanalysis and reconstruction datasets to investigate the internal atmospheric dynamics of the ETCAW. We investigate the role of boreal winter mid-tropospheric heat transport and circulation in providing the energy for the large scale warming. Analyzing sensible heat flux components and regional differences, climate models are not able to reproduce the heat flux evolution found in reanalysis and reconstruction datasets. These datasets show an increase of stationary eddy heat flux and a decrease of transient eddy heat flux during the ETCAW. Moreover, tropospheric circulation analysis reveals the important role of both the Atlantic and the Pacific sectors in the convergence of southerly air masses into the Arctic during the warming event. Subsequently, it is suggested that the internal dynamics of the atmosphere played a major role in the formation in the ETCAW.

  5. Perfect Derived Propagators

    CERN Document Server

    Schulte, Christian

    2008-01-01

    When implementing a propagator for a constraint, one must decide about variants: When implementing min, should one also implement max? Should one implement linear equations both with and without coefficients? Constraint variants are ubiquitous: implementing them requires considerable (if not prohibitive) effort and decreases maintainability, but will deliver better performance. This paper shows how to use variable views, previously introduced for an implementation architecture, to derive perfect propagator variants. A model for views and derived propagators is introduced. Derived propagators are proved to be indeed perfect in that they inherit essential properties such as correctness and domain and bounds consistency. Techniques for systematically deriving propagators such as transformation, generalization, specialization, and channeling are developed for several variable domains. We evaluate the massive impact of derived propagators. Without derived propagators, Gecode would require 140000 rather than 40000 ...

  6. Twentieth Semiannual Report of the Commission to the Congress, July 1956

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Lewis L.

    1956-07-31

    The document represents the twentieth semiannual Atomic Energy Commission (AEC) report to Congress. The report sums up the major activities and developments in the national atomic energy program covering the period January - June 1956.

  7. NASA's unique networking environment

    Science.gov (United States)

    Johnson, Marjory J.

    1988-01-01

    Networking is an infrastructure technology; it is a tool for NASA to support its space and aeronautics missions. Some of NASA's networking problems are shared by the commercial and/or military communities, and can be solved by working with these communities. However, some of NASA's networking problems are unique and will not be addressed by these other communities. Individual characteristics of NASA's space-mission networking enviroment are examined, the combination of all these characteristics that distinguish NASA's networking systems from either commercial or military systems is explained, and some research areas that are important for NASA to pursue are outlined.

  8. NASA Guided Dropsonde Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Exquadrum, Inc. proposes to demonstrate the feasibility of an innovative approach to providing NASA with a Guided Dropsonde (NGD). NASA's desire to use existing...

  9. NASA Space Radiation Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory is a NASA funded facility, delivering heavy ion beams to a target area where scientists...

  10. Chemical Engineering at NASA

    Science.gov (United States)

    Collins, Jacob

    2008-01-01

    This viewgraph presentation is a review of the career paths for chemicals engineer at NASA (specifically NASA Johnson Space Center.) The author uses his personal experience and history as an example of the possible career options.

  11. The Living Universe: NASA and the Development of Astrobiology

    Science.gov (United States)

    Dick, Steven J.; Strick, James E.

    2004-01-01

    In the opening weeks of 1998 a news article in the British journal Nature reported that NASA was about to enter biology in a big way. A "virtual" Astrobiology Institute was gearing up for business, and NASA administrator Dan Goldin told his external advisory council that he would like to see spending on the new institute eventually reach $100 million per year. "You just wait for the screaming from the physical scientists (when that happens)," Goldin was quoted as saying. Nevertheless, by the time of the second Astrobiology Science Conference in 2002, attended by seven hundred scientists from many disciplines, NASA spending on astrobiology had reached nearly half that amount and was growing at a steady pace. Under NASA leadership numerous institutions around the world applied the latest scientific techniques in the service of astrobiology's ambitious goal: the study of what NASA's 1996 Strategic Plan termed the "living universe." This goal embraced nothing less than an understanding of the origin, history, and distribution of life in the universe, including Earth. Astrobiology, conceived as a broad interdisciplinary research program, held the prospect of being the science for the twenty-first century which would unlock the secrets to some of the great questions of humanity. It is no surprise that these age-old questions should continue into the twenty-first century. But that the effort should be spearheaded by NASA was not at all obvious to those - inside and outside the agency - who thought NASA's mission was human spaceflight, rather than science, especially biological science. NASA had, in fact, been involved for four decades in "exobiology," a field that embraced many of the same questions but which had stagnated after the 1976 Viking missions to Mars. In this volume we tell the colorful story of the rise of the discipline of exobiology, how and why it morphed into astrobiology at the end of the twentieth century, and why NASA was the engine for both the

  12. Aerological observations in the tropics in the early twentieth century

    Energy Technology Data Exchange (ETDEWEB)

    Broennimann, Stefan; Stickler, Alexander [Bern Univ. (Switzerland). Oeschger Centre for Climate Change Research and Inst. of Geography

    2013-10-15

    In the first decades of the 20{sup th} century, aerological observations were for the first time performed in tropical regions. One of the most prominent endeavours in this respect was Arthur Berson's aerological expedition to East Africa. Although the main target was the East African monsoon circulation, the expedition provided also other insights that profoundly changed meteorology and climatology. Berson observed that the tropical tropopause was much higher and colder than that over midlatitudes. Moreover, westerly winds were observed in the lower stratosphere, apparently contradicting the high-altitude equatorial easterly winds that were known since the Krakatoa eruption ('Krakatoa easterlies'). The puzzle was only resolved five decades later with the discovery of the Quasi-Biennial Oscillation (QBO). In this paper we briefly summarize the expedition of Berson and review the results in a historical context and in the light of the current research. In the second part of the paper we re-visit Berson's early aerological observations, which we have digitized. We compare the observed wind profiles with corresponding profiles extracted from the 'Twentieth Century Reanalysis', which provides global three-dimensional weather information back to 1871 based on an assimilation of sea-level and surface pressure data. The comparison shows a good agreement at the coast but less good agreement further inland, at the shore of Lake Victoria, where the circulation is more complex. These results demonstrate that Berson's observations are still valuable today as input to current reanalysis systems or for their validation. (orig.)

  13. Aerological observations in the Tropics in the Early Twentieth Century

    Directory of Open Access Journals (Sweden)

    Stefan Brönnimann

    2013-07-01

    Full Text Available In the first decades of the 20th century, aerological observations were for the first time performed in tropical regions. One of the most prominent endeavours in this respect was Arthur Berson's aerological expedition to East Africa. Although the main target was the East African monsoon circulation, the expedition provided also other insights that profoundly changed meteorology and climatology. Berson observed that the tropical tropopause was much higher and colder than that over midlatitudes. Moreover, westerly winds were observed in the lower stratosphere, apparently contradicting the high-altitude equatorial easterly winds that were known since the Krakatoa eruption (“Krakatoa easterlies(”. The puzzle was only resolved five decades later with the discovery of the Quasi-Biennial Oscillation (QBO. In this paper we briefly summarize the expedition of Berson and review the results in a historical context and in the light of the current research. In the second part of the paper we re-visit Berson's early aerological observations, which we have digitized. We compare the observed wind profiles with corresponding profiles extracted from the (“Twentieth Century Reanalysis(”, which provides global three-dimensional weather information back to 1871 based on an assimilation of sea-level and surface pressure data. The comparison shows a good agreement at the coast but less good agreement further inland, at the shore of Lake Victoria, where the circulation is more complex. These results demonstrate that Berson's observations are still valuable today as input to current reanalysis systems or for their validation.

  14. The Wheeler Propagator

    OpenAIRE

    Bollini, C. G.; Rocca, M. C.

    1998-01-01

    We study the half advanced and half retarded Wheeler Green function and its relation to Feynman propagators. First for massless equation. Then, for Klein-Gordon equations with arbitrary mass parameters; real, imaginary or complex. In all cases the Wheeler propagator lacks an on-shell free propagation. The Wheeler function has support inside the light-cone (whatever the mass). The associated vacuum is symmetric with respect to annihilation and creation operators. We show with some examples tha...

  15. Shallow-Water Propagation

    Science.gov (United States)

    2016-06-07

    Shallow- Water Propagation William L. Siegmann Rensselaer Polytechnic Institute 110 Eighth Street Troy, New York 12180-3590 phone: (518) 276...ocean_acoustics LONG-TERM GOALS Develop methods for propagation and coherence calculations in complex shallow- water environments, determine...intensity and coherence. APPROACH (A) Develop high accuracy PE techniques for applications to shallow- water sediments, accounting for

  16. NASA Hazard Analysis Process

    Science.gov (United States)

    Deckert, George

    2010-01-01

    This viewgraph presentation reviews The NASA Hazard Analysis process. The contents include: 1) Significant Incidents and Close Calls in Human Spaceflight; 2) Subsystem Safety Engineering Through the Project Life Cycle; 3) The Risk Informed Design Process; 4) Types of NASA Hazard Analysis; 5) Preliminary Hazard Analysis (PHA); 6) Hazard Analysis Process; 7) Identify Hazardous Conditions; 8) Consider All Interfaces; 9) Work a Preliminary Hazard List; 10) NASA Generic Hazards List; and 11) Final Thoughts

  17. Lunar Surface Propagation Modeling and Effects on Communications

    Science.gov (United States)

    Hwu, Shian U.; Upanavage, Matthew; Sham, Catherine C.

    2008-01-01

    This paper analyzes the lunar terrain effects on the signal propagation of the planned NASA lunar wireless communication and sensor systems. It is observed that the propagation characteristics are significantly affected by the presence of the lunar terrain. The obtained results indicate that the terrain geometry, antenna location, and lunar surface material are important factors determining the propagation characteristics of the lunar wireless communication systems. The path loss can be much more severe than the free space propagation and is greatly affected by the antenna height, operating frequency, and surface material. The analysis results from this paper are important for the lunar communication link margin analysis in determining the limits on the reliable communication range and radio frequency coverage performance at planned lunar base worksites. Key Words lunar, multipath, path loss, propagation, wireless.

  18. The Wheeler Propagator

    CERN Document Server

    Bollini, C G

    1998-01-01

    We study the half advanced and half retarded Wheeler Green function and its relation to Feynman propagators. First for massless equation. Then, for Klein-Gordon equations with arbitrary mass parameters; real, imaginary or complex. In all cases the Wheeler propagator lacks an on-shell free propagation. The Wheeler function has support inside the light-cone (whatever the mass). The associated vacuum is symmetric with respect to annihilation and creation operators. We show with some examples that perturbative unitarity holds, whatever the mass (real or complex). Some possible applications are discussed.

  19. Ultra reliability at NASA

    Science.gov (United States)

    Shapiro, Andrew A.

    2006-01-01

    Ultra reliable systems are critical to NASA particularly as consideration is being given to extended lunar missions and manned missions to Mars. NASA has formulated a program designed to improve the reliability of NASA systems. The long term goal for the NASA ultra reliability is to ultimately improve NASA systems by an order of magnitude. The approach outlined in this presentation involves the steps used in developing a strategic plan to achieve the long term objective of ultra reliability. Consideration is given to: complex systems, hardware (including aircraft, aerospace craft and launch vehicles), software, human interactions, long life missions, infrastructure development, and cross cutting technologies. Several NASA-wide workshops have been held, identifying issues for reliability improvement and providing mitigation strategies for these issues. In addition to representation from all of the NASA centers, experts from government (NASA and non-NASA), universities and industry participated. Highlights of a strategic plan, which is being developed using the results from these workshops, will be presented.

  20. Quantum generations: a history of physics in the twentieth century

    Energy Technology Data Exchange (ETDEWEB)

    Rechenberg, H

    2000-11-01

    Full text: The author attempts to handle the most important physics development of the twentieth century, namely that of quantum theory, in one, not too bulky, volume. This heroic task is split into 29 chapters, each treating a topic that forms a well defined subpart of the big theme embracing quantum theory itself (and also some of its companions), and the experimental discoveries, technology, sociology and science politics connected with it. The contents of Part One cover roughly the first twenty years of the century. There are also chapters on the introduction of the quantum of action and atomic constitution, on discharge in gases, low-temperature research and the interaction of science with industrial and military affairs in World War I. Part Two, leading up to the Hiroshima bomb, includes, beyond such central chapters as the rise of nuclear physics, quantum field theory and the physical and philosophical interpretation of quantum mechanics, further accounts of the Eddington-Milne cosmology, physics in the dictatorial regimes of National Socialism, Fascism and Stalinism, and the intellectual immigration during the 1930s into the USA. Part Three brings the story up to the end of the century, embracing great topics like nuclear energy, Big Science (i.e. physics in military and civil projects), fundamental particle theories up to speculations about 'grand unification', quantum electronics, or the increasingly hostile attitude toward science in the past 30 years. The short Part Four contains two chapters on a century in retrospect, which was really the century of physics. An enormous amount of material has been addressed in this book, and one wonders how one person can say anything reasonable about all these topics. The overall organization and the selection of chapters appears to be well planned and carried out quite successfully. In this reviewer's opinion, some chapters, e.g. on Dirac's theoretical work or cosmology (on which the author has

  1. Diagnosis and authority in the early-twentieth-century medical practice of Richard C. Cabot.

    Science.gov (United States)

    Crenner, Christopher

    2002-01-01

    This paper examines diagnostic practices using the early twentieth-century medical literature and the patient correspondence and records from the clinic of Richard Cabot. What shaped medicine's rapidly growing persuasive authority in the twentieth century? Diagnostic expertise demonstrated the doctor's control over disease but offered a service of ambiguous value to patients. Cabot and his peers offered differing views on how new diagnostic techniques would influence their relationships to their patients. In his busy private clinic Cabot put into effect an exacting diagnostic process, modeled on his innovative Clinicopathological Conferences. The people who came to the clinic often sought his technical expertise but accepted his diagnostic practices and opinions sometimes only provisionally.

  2. The Rise of Obesity in Europe, A Twentieth Century Food History

    OpenAIRE

    Tenna Jensen

    2010-01-01

    The publication of ‘The rise of obesity in Europe. A twentieth century Food History’ is a contribution to the vast and recent literature produced on issues of food and alimentary changes in Europe. The edited volume is based on a symposium titled “From Under-nutrition to Obesity: Changes in Food Consumption in Twentieth-Century-Europe” held in September 2007 at SIFO (National Institute for Consumer Research) in Oslo.The volume contains a wide range of research traditions. Many fruitful debate...

  3. Industrial Characteristics and Employment of Older Manufacturing Workers in the Early-Twentieth-Century United States

    Science.gov (United States)

    Lee, Chulhee

    2015-01-01

    This study explores how industry-specific technological, organizational, and managerial features affected the employment of old male manufacturing workers in the early twentieth-century United States. Industrial characteristics favorably related to the employment of old industrial workers include high labor productivity, less capital- and material-intensive production, short workdays, low intensity of work, high job flexibility, and formalized employment relationship. Results show that aged industrial workers were heavily concentrated in “unfavorable” industries, suggesting that the contemporary argument of “industrial scrap heap” was applicable for most of the manufacturing workers in the early twentieth century United States. PMID:26989273

  4. NASA Facts, Voyager.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC. Educational Programs Div.

    This document is one of a series of publications of the National Aeronautics and Space Administration (NASA) on facts about the exploration of Jupiter and Saturn. This NASA mission consists of two unmanned Voyager spacecrafts launched in August and September of 1977, and due to arrive at Jupiter in 1979. An account of the scientific equipment…

  5. A Sociological Look at Biofuels: Ethanol in the Early Decades of the Twentieth Century and Lessons for Today

    Science.gov (United States)

    Carolan, Michael S.

    2009-01-01

    This article develops a broad sociological understanding of why biofuels lost out to leaded gasoline as the fuel par excellence of the twentieth century, while drawing comparisons with biofuels today. It begins by briefly discussing the fuel-scape in the United States in the late nineteenth and early twentieth centuries, examining the farm…

  6. A Sociological Look at Biofuels: Ethanol in the Early Decades of the Twentieth Century and Lessons for Today

    Science.gov (United States)

    Carolan, Michael S.

    2009-01-01

    This article develops a broad sociological understanding of why biofuels lost out to leaded gasoline as the fuel par excellence of the twentieth century, while drawing comparisons with biofuels today. It begins by briefly discussing the fuel-scape in the United States in the late nineteenth and early twentieth centuries, examining the farm…

  7. The NASA astrobiology program.

    Science.gov (United States)

    Morrison, D

    2001-01-01

    The new discipline of astrobiology addresses fundamental questions about life in the universe: "Where did we come from?" "Are we alone in the universe?" "What is our future beyond the Earth?" Developing capabilities in biotechnology, informatics, and space exploration provide new tools to address these old questions. The U.S. National Aeronautics and Space Administration (NASA) has encouraged this new discipline by organizing workshops and technical meetings, establishing a NASA Astrobiology Institute, providing research funds to individual investigators, ensuring that astrobiology goals are incorporated in NASA flight missions, and initiating a program of public outreach and education. Much of the initial effort by NASA and the research community was focused on determining the technical content of astrobiology. This paper discusses the initial answer to the question "What is astrobiology?" as described in the NASA Astrobiology Roadmap.

  8. K-band mobile propagation measurements using ACTS

    Science.gov (United States)

    Goldhirsh, Julius; Vogel, Wolfhard J.; Torrence, Geoffrey W.

    1993-01-01

    An overview of two planned propagation campaigns employing land-mobile scenarios with ACTS is presented. The campaigns will be undertaken through a joint effort involving the Johns Hopkins University, Applied Physics Laboratory (APL), The University of Texas at Austin, Electrical Engineering Research Laboratory (EERL), and the NASA Lewis Research Center (NASA LeRC). Propagation campaigns are planned in Central Maryland in November 1993 (elevation angle approx. equals 40 deg.) and in Fairbanks, Alaska in June 1994 (elevation angle approx. equals 8 deg.) employing a computer controlled antenna tracking system located atop a van containing a receiver/data acquisition system. The antenna will track (in azimuth) downlink transmissions at 19.914 GHz from ACTS during the mobile propagation measurements. The major objectives of the campaigns are to measure the fade and multipath effects of trees and terrain at 20 GHz for rural and suburban scenarios and to extend existing models which were previously validated at UHF to S-Band.

  9. Benjamin Moore, Science, and Medical Planning in Early Twentieth-Century Britain

    Science.gov (United States)

    Lawson, Gordon S.

    2008-01-01

    Benjamin Moore (1867-1922), physiologist and biochemist, was an eminent member of the British scientific and medical community in the early twentieth century. As a founder and president of the State Medical Services Association (SMSA) from its establishment in 1912 until his untimely death in 1922, Moore was a prominent medical services activist…

  10. Sociology of Twentieth Century Congregate Care of the Developmentally Disabled-Recollections

    Science.gov (United States)

    Daly, William C.

    2005-01-01

    Elements of the twentieth century care facility of state origin are enumerated as the reader hopefully gets some idea of the social milieu or ethos of that period and the management profile thought to be proper and expeditious for unfortunate, homeless and poorly adjusted citizens. The life of staff and patients within these state sponsored…

  11. Translation, Hybridization, and Modernization: John Dewey and Children's Literature in Early Twentieth Century China

    Science.gov (United States)

    Xu, Xu

    2013-01-01

    This essay examines how John Dewey's child-centered educational philosophy was adopted and adapted in the early twentieth century in China to create a Chinese children's literature. Chinese intellectuals applied Dewey's educational philosophy, which values children's interests and needs, to formulate a new concept of modern childhood that…

  12. Singing the Nation into Being: Teaching Identity and Culture at the Turn of the Twentieth Century

    Science.gov (United States)

    Sargeant, Lynn M.

    2009-01-01

    In this article, the author compares the music education in the United States and the Russian Empire at the turn of the twentieth century. In both countries, music educators struggled to secure a permanent role for vocal music in the school. By comparing Russian music instruction to that in the United States, educators can better understand not…

  13. Westward Bound? Dutch Education and Cultural Transfer in the Mid-Twentieth Century

    Science.gov (United States)

    Bakker, Nelleke

    2014-01-01

    This article discusses the transition from philosophy to psychology as the main source of inspiration for education during the mid-twentieth century in the Netherlands, situated between Germany in the east and the English-speaking world in the west. Claims have been made that educational theory in the Netherlands was dominated by German philosophy…

  14. Widening horizons?: the geography of the marriage market in nineteenth and early-twentieth century Netherlands

    NARCIS (Netherlands)

    Ekamper, P.; van Poppel, F.W.A.; Mandemakers, K.; P. Gutmann, Myron; D. Deane, Glenn; R. Merchant, Emily; M. Sylvester, Kenneth

    2011-01-01

    Historical studies suggest that nineteenth- and twentieth-century processes of national integration in the countries of Western Europe fundamentally changed interactions between individuals living in different parts of those countries. These studies, however, were rarely able to provide direct evide

  15. Conceptual Revolutions in Twentieth-Century Art. NBER Working Paper No. 15073

    Science.gov (United States)

    Galenson, David

    2009-01-01

    Art critics and scholars have acknowledged the breakdown of their explanations and narratives of contemporary art in the face of what they consider the incoherent era of "pluralism" or "postmodernism" that began in the late twentieth century. This failure is in fact a result of their inability to understand the nature of the development of…

  16. Science, occultism, and the art of the avant-garde in the early twentieth century

    NARCIS (Netherlands)

    Bauduin, T.M.

    2012-01-01

    In the early twentieth century, scientific discoveries such as n-dimensionality, x-rays, and electromagnetism made their way into the discourse of Occultism, where they were subsequently reframed as the occult fourth dimension, clairvoyant x-ray vision, and thought vibration. As this article will sh

  17. "Are You Only an Applauder?" American Music Correspondence Schools in the Early Twentieth Century

    Science.gov (United States)

    Vogel, Dorothy

    2015-01-01

    The purpose of this study was to examine correspondence schools of music in the early twentieth century. Advertisements in widely circulated household and music periodicals and archival copies of courses from Siegel-Myers Correspondence School of Music, United States School of Music, American College of Music, and others were examined. Research…

  18. Scholarly Publishing: Books, Journals, Publishers, and Libraries in the Twentieth Century.

    Science.gov (United States)

    Abel, Richard E., Ed.; Newlin, Lyman W., Ed.

    2002-01-01

    In this volume, publishers, booksellers, journal dealers, and librarians share their views on libraries and publishing. While the information/knowledge transfer process in the entire span of the twentieth century was to be addressed by the contributors, the principal focus of every author was to be the last five decades in which the most profound,…

  19. Harmonisation and South African Languages: Twentieth Century Debates of Homogeneity and Heterogeneity

    Science.gov (United States)

    Heugh, Kathleen

    2016-01-01

    This article offers a historiographic analysis of twentieth century debates amongst agents with linguistic, missionary and ideological interest in the standardisation or harmonisation of two widely used clusters of languages in South Africa, Nguni and Sotho. The discussion illustrates how faith-based and political ideologies interact with and…

  20. Educational Testing as an Accountability Measure: Drawing on Twentieth-Century Danish History of Education Experiences

    Science.gov (United States)

    Ydesen, Christian

    2013-01-01

    This article reveals perspectives based on experiences from twentieth-century Danish educational history by outlining contemporary, test-based accountability regime characteristics and their implications for education policy. The article introduces one such characteristic, followed by an empirical analysis of the origins and impacts of test-based…

  1. Intertransitions between Islam and Eastern Orthodoxy in Kazakhstan (Nineteenth-Early Twentieth Centuries)

    Science.gov (United States)

    Sadvokasova, Zakish T.; Orazbayeva, Altynay I.

    2016-01-01

    The purpose of this paper is to review the historical facts related to conversion of indigenous people of the Kazakh steppe from Islam to Christianity and the conversion of the Russian migrants from Orthodoxy to Islam in Kazakhstan in the nineteenth-early twentieth century. The study deals with the laws that were detrimental to Islam and reforms…

  2. Teaching the French Revolution: Lessons and Imagery from Nineteenth and Twentieth Century Textbooks

    Science.gov (United States)

    Harison, Casey

    2002-01-01

    This article considers the "myths" and negative images of the French Revolution which were fashioned in the United States by examining interpretations found in nineteenth and twentieth-century American school texts. The texts are part of the Floyd Family Collection at Indiana State University, representing books used in Indiana schools,…

  3. "Are You Only an Applauder?" American Music Correspondence Schools in the Early Twentieth Century

    Science.gov (United States)

    Vogel, Dorothy

    2015-01-01

    The purpose of this study was to examine correspondence schools of music in the early twentieth century. Advertisements in widely circulated household and music periodicals and archival copies of courses from Siegel-Myers Correspondence School of Music, United States School of Music, American College of Music, and others were examined. Research…

  4. No issue, no problem? Co-education in dutch secondary physical education during the twentieth century

    NARCIS (Netherlands)

    van Essen, H.W.

    2003-01-01

    This article places the current state of Dutch co-education in physical education into a longitudinal perspective. Occasionally, comparisons are made with Germany and England. The dominant, twentieth-century, co-educational tradition in the Netherlands including its pragmatic argumentation has influ

  5. Harbingers of Feminism? Gender, Cultural Capital and Education in Mid-Twentieth-Century Rural Wales

    Science.gov (United States)

    Baker, Sally; Brown, Brian

    2009-01-01

    This paper reports the results of a small-scale narrative study of men and women who grew up in mid-twentieth-century rural Wales, and their reminiscences regarding women and education. Although the dominant image of Wales during that era is that of a male-dominated society, all of our participants remembered influential independent women and…

  6. Twentieth-Century Transformation in Catalonia and the Ukraine: Ethnic Implications in Education.

    Science.gov (United States)

    Petherbridge-Hernandez, Patricia; Raby, Rosalind Latiner

    1993-01-01

    Traces the parallel histories of cultural and language preservation in the minority regions of Catalonia (Spain) and Ukraine (former Soviet Union) during the twentieth century. Discusses large societal changes, national government policies about language of instruction, bilingual education, the comparative status of Catalan and Ukrainian, and…

  7. Intellectual Portraits: Politics, Professions and Identity in Twentieth-Century England

    Science.gov (United States)

    Martin, Jane

    2014-01-01

    This article brings together six talented women historians in twentieth-century England whose scholarly productions helped shape modern historical practice but who are little known in the canonical accounts of history-writing in the period. The author is looking to map and describe historical communities from a grounded and qualitative perspective…

  8. Regional Variation and Convergence of Height and Living Conditions in Sweden During the Twentieth Century

    Directory of Open Access Journals (Sweden)

    Stefan Öberg

    2017-04-01

    Full Text Available This study investigates regional differences in height in Sweden during the twentieth century using data from universal conscript inspections (for men. We find substantive differences (2-3 cm in height between the counties. Men in the southern, southeastern and northernmost parts of Sweden were shorter. Men in the Stockholm and Göteborg regions were taller and we find no “urban penalty” in height. The differences in height between counties declined over the course of the twentieth century and the average height increased more in the counties with an initially shorter average height. We find the expected positive associations between height and the real wage in manufacturing and the regional GDP per capita respectively. The real wage in the manufacturing sector is more consistently associated with the county average height than that for the agricultural sector. Contrary to expectations, we find that the men were consistently taller in counties with higher food prices and where the relative price of animal foods was higher. The average height was negatively associated with the infant mortality rate during the men’s childhood in the mid-twentieth century. The association was less clear in the early twentieth century.

  9. No issue, no problem? Co-education in dutch secondary physical education during the twentieth century

    NARCIS (Netherlands)

    van Essen, H.W.

    This article places the current state of Dutch co-education in physical education into a longitudinal perspective. Occasionally, comparisons are made with Germany and England. The dominant, twentieth-century, co-educational tradition in the Netherlands including its pragmatic argumentation has

  10. Energy Exchange NASA Opening Plenary

    Science.gov (United States)

    Marrs, Rick

    2017-01-01

    Rick Marrs, Deputy Assistant Administrator Office of Strategic Infrastructure NASA Headquarters will be speaking during the 2017 Energy Exchange opening plenary. His presentation showcases the NASA mission, sustainability at NASA, NASA's strategic Sustainability Performance Plan, Existing PV Partnerships, and NASA funded Solar Initiatives at KSC.

  11. Hierarchical Affinity Propagation

    CERN Document Server

    Givoni, Inmar; Frey, Brendan J

    2012-01-01

    Affinity propagation is an exemplar-based clustering algorithm that finds a set of data-points that best exemplify the data, and associates each datapoint with one exemplar. We extend affinity propagation in a principled way to solve the hierarchical clustering problem, which arises in a variety of domains including biology, sensor networks and decision making in operational research. We derive an inference algorithm that operates by propagating information up and down the hierarchy, and is efficient despite the high-order potentials required for the graphical model formulation. We demonstrate that our method outperforms greedy techniques that cluster one layer at a time. We show that on an artificial dataset designed to mimic the HIV-strain mutation dynamics, our method outperforms related methods. For real HIV sequences, where the ground truth is not available, we show our method achieves better results, in terms of the underlying objective function, and show the results correspond meaningfully to geographi...

  12. Propagation of waves

    CERN Document Server

    David, P

    2013-01-01

    Propagation of Waves focuses on the wave propagation around the earth, which is influenced by its curvature, surface irregularities, and by passage through atmospheric layers that may be refracting, absorbing, or ionized. This book begins by outlining the behavior of waves in the various media and at their interfaces, which simplifies the basic phenomena, such as absorption, refraction, reflection, and interference. Applications to the case of the terrestrial sphere are also discussed as a natural generalization. Following the deliberation on the diffraction of the "ground? wave around the ear

  13. NASA Image Exchange (NIX)

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA Technical Reports Server (NTRS) provides access to aerospace-related citations, full-text online documents, and images and videos. The types of information...

  14. My NASA Data

    Data.gov (United States)

    National Aeronautics and Space Administration — MY NASA DATA (MND) is a tool that allows anyone to make use of satellite data that was previously unavailable.Through the use of MND’s Live Access Server (LAS) a...

  15. NASA Techport API

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA TechPort system provides a RESTful web services API to make technology project data available in a machine-readable format. This API can be used to export...

  16. NASA Earth Exchange (NEX)

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA Earth Exchange (NEX) represents a new platform for the Earth science community that provides a mechanism for scientific collaboration and knowledge sharing....

  17. NASA Space Sounds API

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has released a series of space sounds via sound cloud. We have abstracted away some of the hassle in accessing these sounds, so that developers can play with...

  18. NASA Water Resources Program

    Science.gov (United States)

    Toll, David L.

    2011-01-01

    With increasing population pressure and water usage coupled with climate variability and change, water issues are being reported by numerous groups as the most critical environmental problems facing us in the 21st century. Competitive uses and the prevalence of river basins and aquifers that extend across boundaries engender political tensions between communities, stakeholders and countries. In addition to the numerous water availability issues, water quality related problems are seriously affecting human health and our environment. The potential crises and conflicts especially arise when water is competed among multiple uses. For example, urban areas, environmental and recreational uses, agriculture, and energy production compete for scarce resources, not only in the Western U.S. but throughout much of the U.S. and also in numerous parts of the world. Mitigating these conflicts and meeting water demands and needs requires using existing water resources more efficiently. The NASA Water Resources Program Element works to use NASA products and technology to address these critical water issues. The primary goal of the Water Resources is to facilitate application of NASA Earth science products as a routine use in integrated water resources management for the sustainable use of water. This also includes the extreme events of drought and floods and the adaptation to the impacts from climate change. NASA satellite and Earth system observations of water and related data provide a huge volume of valuable data in both near-real-time and extended back nearly 50 years about the Earth's land surface conditions such as precipitation, snow, soil moisture, water levels, land cover type, vegetation type, and health. NASA Water Resources Program works closely to use NASA and Earth science data with other U.S. government agencies, universities, and non-profit and private sector organizations both domestically and internationally. The NASA Water Resources Program organizes its

  19. The NASA Auralization Framework and Plugin Architecture

    Science.gov (United States)

    Aumann, Aric R.; Tuttle, Brian C.; Chapin, William L.; Rizzi, Stephen A.

    2015-01-01

    NASA has a long history of investigating human response to aircraft flyover noise and in recent years has developed a capability to fully auralize the noise of aircraft during their design. This capability is particularly useful for unconventional designs with noise signatures significantly different from the current fleet. To that end, a flexible software architecture has been developed to facilitate rapid integration of new simulation techniques for noise source synthesis and propagation, and to foster collaboration amongst researchers through a common releasable code base. The NASA Auralization Framework (NAF) is a skeletal framework written in C++ with basic functionalities and a plugin architecture that allows users to mix and match NAF capabilities with their own methods through the development and use of dynamically linked libraries. This paper presents the NAF software architecture and discusses several advanced auralization techniques that have been implemented as plugins to the framework.

  20. NASA thesaurus aeronautics vocabulary

    Science.gov (United States)

    1991-01-01

    The controlled vocabulary used by the NASA Scientific and Technical Information effort to index documents in the area of aeronautics is presented. The terms comprise a subset of the 1988 edition of the NASA Thesaurus and its supplements issued through the end of 1990. The Aeronautics Vocabulary contains over 4700 terms presented in a hierarchical display format. In addition to aeronautics per se, the vocabulary covers supporting terminology from areas such as fluid dynamics, propulsion engineering, and test facilities and instrumentation.

  1. NASA thesaurus: Astronomy vocabulary

    Science.gov (United States)

    1988-01-01

    A terminology of descriptors used by the NASA Scientific and Technical information effort to index documents in the area of astronomy is presented. The terms are listed in hierarchical format derived from the 1988 edition of the NASA Thesaurus Volume 1 -- Hierarchical Listing. Over 1600 terms are included. In addition to astronomy, space sciences covered include astrophysics, cosmology, lunar flight and exploration, meteors and meteorites, celestial mechanics, planetary flight and exploration, and planetary science.

  2. DROMO propagator revisited

    Science.gov (United States)

    Urrutxua, Hodei; Sanjurjo-Rivo, Manuel; Peláez, Jesús

    2016-01-01

    In the year 2000 an in-house orbital propagator called DROMO (Peláez et al. in Celest Mech Dyn Astron 97:131-150, 2007. doi: 10.1007/s10569-006-9056-3) was developed by the Space Dynamics Group of the Technical University of Madrid, based in a set of redundant variables including Euler-Rodrigues parameters. An original deduction of the DROMO propagator is carried out, underlining its close relation with the ideal frame concept introduced by Hansen (Abh der Math-Phys Cl der Kon Sachs Ges der Wissensch 5:41-218, 1857). Based on the very same concept, Deprit (J Res Natl Bur Stand Sect B Math Sci 79B(1-2):1-15, 1975) proposed a formulation for orbit propagation. In this paper, similarities and differences with the theory carried out by Deprit are analyzed. Simultaneously, some improvements are introduced in the formulation, that lead to a more synthetic and better performing propagator. Also, the long-term effect of the oblateness of the primary is studied in terms of DROMO variables, and new numerical results are presented to evaluate the performance of the method.

  3. Shallow Water Propagation

    Science.gov (United States)

    2014-09-30

    response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and...these modes decay much more slowly than leaky modes as they propagate. The initial focus is on modal phase and group velocity formulas, obtained from...acoustic quantities such as transmission loss and scintillation index. (C) Both physical understanding and reasonable estimates of

  4. NASA Planetary Visualization Tool

    Science.gov (United States)

    Hogan, P.; Kim, R.

    2004-12-01

    NASA World Wind allows one to zoom from satellite altitude into any place on Earth, leveraging the combination of high resolution LandSat imagery and SRTM elevation data to experience Earth in visually rich 3D, just as if they were really there. NASA World Wind combines LandSat 7 imagery with Shuttle Radar Topography Mission (SRTM) elevation data, for a dramatic view of the Earth at eye level. Users can literally fly across the world's terrain from any location in any direction. Particular focus was put into the ease of usability so people of all ages can enjoy World Wind. All one needs to control World Wind is a two button mouse. Additional guides and features can be accessed though a simplified menu. Navigation is automated with single clicks of a mouse as well as the ability to type in any location and automatically zoom to it. NASA World Wind was designed to run on recent PC hardware with the same technology used by today's 3D video games. NASA World Wind delivers the NASA Blue Marble, spectacular true-color imagery of the entire Earth at 1-kilometer-per-pixel. Using NASA World Wind, you can continue to zoom past Blue Marble resolution to seamlessly experience the extremely detailed mosaic of LandSat 7 data at an impressive 15-meters-per-pixel resolution. NASA World Wind also delivers other color bands such as the infrared spectrum. The NASA Scientific Visualization Studio at Goddard Space Flight Center (GSFC) has produced a set of visually intense animations that demonstrate a variety of subjects such as hurricane dynamics and seasonal changes across the globe. NASA World Wind takes these animations and plays them directly on the world. The NASA Moderate Resolution Imaging Spectroradiometer (MODIS) produces a set of time relevant planetary imagery that's updated every day. MODIS catalogs fires, floods, dust, smoke, storms and volcanic activity. NASA World Wind produces an easily customized view of this information and marks them directly on the globe. When one

  5. NASA Systems Engineering Handbook

    Science.gov (United States)

    Hirshorn, Steven R.; Voss, Linda D.; Bromley, Linda K.

    2017-01-01

    The update of this handbook continues the methodology of the previous revision: a top-down compatibility with higher level Agency policy and a bottom-up infusion of guidance from the NASA practitioners in the field. This approach provides the opportunity to obtain best practices from across NASA and bridge the information to the established NASA systems engineering processes and to communicate principles of good practice as well as alternative approaches rather than specify a particular way to accomplish a task. The result embodied in this handbook is a top-level implementation approach on the practice of systems engineering unique to NASA. Material used for updating this handbook has been drawn from many sources, including NPRs, Center systems engineering handbooks and processes, other Agency best practices, and external systems engineering textbooks and guides. This handbook consists of six chapters: (1) an introduction, (2) a systems engineering fundamentals discussion, (3) the NASA program project life cycles, (4) systems engineering processes to get from a concept to a design, (5) systems engineering processes to get from a design to a final product, and (6) crosscutting management processes in systems engineering. The chapters are supplemented by appendices that provide outlines, examples, and further information to illustrate topics in the chapters. The handbook makes extensive use of boxes and figures to define, refine, illustrate, and extend concepts in the chapters.

  6. NASA Bioreactor Demonstration System

    Science.gov (United States)

    2002-01-01

    Leland W. K. Chung (left), Director, Molecular Urology Therapeutics Program at the Winship Cancer Institute at Emory University, is principal investigator for the NASA bioreactor demonstration system (BDS-05). With him is Dr. Jun Shu, an assistant professor of Orthopedics Surgery from Kuming Medical University China. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  7. Propagating Instabilities in Solids

    Science.gov (United States)

    Kyriakides, Stelios

    1998-03-01

    Instability is one of the factors which limit the extent to which solids can be loaded or deformed and plays a pivotal role in the design of many structures. Such instabilities often result in localized deformation which precipitates catastrophic failure. Some materials have the capacity to recover their stiffness following a certain amount of localized deformation. This local recovery in stiffness arrests further local deformation and spreading of the instability to neighboring material becomes preferred. Under displacement controlled loading the propagation of the transition fronts can be achieved in a steady-state manner at a constant stress level known as the propagation stress. The stresses in the transition fronts joining the highly deformed zone to the intact material overcome the instability nucleation stresses and, as a result, the propagation stress is usually much lower than the stress required to nucleate the instability. The classical example of this class of material instabilities is L/"uders bands which tend to affect mild steels and other metals. Recent work has demonstrated that propagating instabilities occur in several other materials. Experimental and analytical results from four examples will be used to illustrate this point: First the evolution of L=FCders bands in mild steel strips will be revisited. The second example involves the evolution of stress induced phase transformations (austenite to martensite phases and the reverse) in a shape memory alloy under displacement controlled stretching. The third example is the crushing behavior of cellular materials such as honeycombs and foams made from metals and polymers. The fourth example involves the axial broadening/propagation of kink bands in aligned fiber/matrix composites under compression. The microstructure and, as a result, the micromechanisms governing the onset, localization, local arrest and propagation of instabilities in each of the four materials are vastly different. Despite this

  8. Technological Innovations from NASA

    Science.gov (United States)

    Pellis, Neal R.

    2006-01-01

    The challenge of human space exploration places demands on technology that push concepts and development to the leading edge. In biotechnology and biomedical equipment development, NASA science has been the seed for numerous innovations, many of which are in the commercial arena. The biotechnology effort has led to rational drug design, analytical equipment, and cell culture and tissue engineering strategies. Biomedical research and development has resulted in medical devices that enable diagnosis and treatment advances. NASA Biomedical developments are exemplified in the new laser light scattering analysis for cataracts, the axial flow left ventricular-assist device, non contact electrocardiography, and the guidance system for LASIK surgery. Many more developments are in progress. NASA will continue to advance technologies, incorporating new approaches from basic and applied research, nanotechnology, computational modeling, and database analyses.

  9. Propagation effects handbook for satellite systems design. A summary of propagation impairments on 10 to 100 GHz satellite links with techniques for system design

    Science.gov (United States)

    Ippolito, Louis J.

    1989-01-01

    The NASA Propagation Effects Handbook for Satellite Systems Design provides a systematic compilation of the major propagation effects experienced on space-Earth paths in the 10 to 100 GHz frequency band region. It provides both a detailed description of the propagation phenomenon and a summary of the impact of the effect on the communications system design and performance. Chapter 2 through 5 describe the propagation effects, prediction models, and available experimental data bases. In Chapter 6, design techniques and prediction methods available for evaluating propagation effects on space-Earth communication systems are presented. Chapter 7 addresses the system design process and how the effects of propagation on system design and performance should be considered and how that can be mitigated. Examples of operational and planned Ku, Ka, and EHF satellite communications systems are given.

  10. A historical synopsis of farm animal disease and public policy in twentieth century Britain.

    Science.gov (United States)

    Woods, Abigail

    2011-07-12

    The diseases suffered by British livestock, and the ways in which they were perceived and managed by farmers, vets and the state, changed considerably over the course of the twentieth century. This paper documents and analyses these changes in relation to the development of public policy. It reveals that scientific knowledge and disease demographics cannot by themselves explain the shifting boundaries of state responsibility for animal health, the diseases targeted and the preferred modes of intervention. Policies were shaped also by concerns over food security and the public's health, the state of the national and livestock economy, the interests and expertise of the veterinary profession, and prevailing agricultural policy. This paper demonstrates how, by precipitating changes to farming and trading practices, public policy could sometimes actually undermine farm animal health. Animal disease can therefore be viewed both as a stimulus to, and a consequence of, twentieth century public policy.

  11. New perspectives on forced migration in the history of twentieth-century neuroscience.

    Science.gov (United States)

    Stahnisch, Frank W; Russell, Gül

    2016-01-01

    This special issue of the Journal of the History of the Neurosciences, comprised of six articles and one commentary, reflects on the multifold dimensions of intellectual migration in the neurosciences and illustrates them by relevant case studies, biographies, and surveys from twentieth-century history of science and medicine perspectives. The special issue as a whole strives to emphasize the impact of forced migration in the neurosciences and psychiatry from an interdisciplinary perspective by, first, describing the general research topic, second, by showing how new models can be applied to the historiography and social studies of twentieth-century neuroscience, and, third, by providing a deeper understanding of the impact of European émigré researchers on emerging allied fields, such as neurogenetics, biological psychiatry, psychosomatics, and public mental health, etc. as resulting from this process at large.

  12. Oral history, subjectivity, and environmental reality: occupational health histories in twentieth-century Scotland.

    Science.gov (United States)

    Johnston, Ronnie; McIvor, Arthur

    2004-01-01

    This essay uses oral histories of dust disease in twentieth-century Scotland to illustrate the ways in which such history can illuminate how the working environment and work cultures affect workers' bodies and how workers come to terms with the ill-health caused by their employment. It emphasizes the agency of the interpreter but argues further that oral histories of dust disease in twentieth-century Scotland are simultaneously influenced by, and evidence for, material conditions. The essay explores the notion that the bodies, not just the voices of interviewees, are material testament to health-corroding work practices, cultures, and habitat. The focus is the problems caused by the inhalation of coal and asbestos dust.

  13. The dearth of the clinic: lead, air, and agency in twentieth-century America.

    Science.gov (United States)

    Sellers, Christopher

    2003-07-01

    By surveying myriad ways that twentieth-century American experts and nonexperts grappled with the health implications of aerial exposures to lead or substances that may have contained lead, this paper urges medical historians' attention toward environments-workplaces, homes and the outdoors-and their extrabodily ontology. Health histories framed around dust, toxins, fumes, and pollution rather than around particular diseases challenge long-accepted narratives, such as Hibbert Hill's old generalization about a "New Public Health" shift from "the environment to the individual." Greater environmental focus can also advance "bottom-up" health history. Pushing the gaze of twentieth-century medical and public health historians beyond hospitals, "public health" departments, clinically confirmable disease, and "patient" roles, it draws historians' attention to health-related realms in which laypeople often claimed greater knowledge and competence.

  14. Rabid epidemiologies: the emergence and resurgence of rabies in twentieth century South Africa.

    Science.gov (United States)

    Brown, Karen

    2011-01-01

    This article discusses the history of rabies in South Africa since the early twentieth century. It argues that rabies is a zoonotic disease that traverses rural and urban spaces, that transfers itself between wild and domestic animals and remains a potential threat to human life in the region. Scientists discovered an indigenous form of rabies, found primarily in the yellow mongoose, after the first biomedically confirmed human fatalities in 1928. Since the 1950s canine rabies, presumed to have moved southwards from across the Zambezi River, has become endemic also. South Africa is home to a comparatively large number of rabies strains and animal carriers, making it a particularly interesting case study. Environmental changes during the colonial and apartheid periods have helped to explain the increase in rabies cases since the mid-twentieth century. Moreover, developments in the biological and ecological sciences have provided insights into why the rabies virus has become endemic in certain wildlife species.

  15. The Science of Symbiosis and Linguistic Democracy in Early Twentieth-century Japan

    Directory of Open Access Journals (Sweden)

    Sho Konishi

    2015-04-01

    Full Text Available Focusing on the early twentieth-century Japanese Esperantist and popular celebrity writer Miyazawa Kenji as an embodiment of a larger intellectual phenomenon of early twentieth century Japan, the essay delineates the scientific world view behind the Esperanto movement and corresponding internal logic that developed in the language movement's foundational years. It argues that Esperantism in Japan in its early years was not an isolated linguistic movement among a small number of leftist intellectuals, but part of a much larger intellectual, cultural, and social movement that reflected the particular scientific worldview of what I call 'anarchist science'. This worldview defied the conceptual bifurcations of 'modern vs. tradition' and 'nature vs. culture' in modern history. A history of its vision offers a fresh perspective on modern history, future visions of the past, and the historical meanings of Esperantism.

  16. The concept of time in early twentieth-century philosophy a philosophical thematic atlas

    CERN Document Server

    2016-01-01

    This book presents a collection of authoritative contributions on the concept of time in early twentieth-century philosophy. It is structured in the form of a thematic atlas: each section is accompanied by relevant elementary logic maps that reproduce in a “spatial” form the directionalities (arguments and/or discourses) reported on in the text. The book is divided into three main sections, the first of which covers phenomenology and the perception of time by analyzing the works of Bergson, Husserl, Sartre, Merleau-Ponty, Deleuze, Guattari and Derrida. The second section focuses on the language and conceptualization of time, examining the works of Cassirer, Wittgenstein, Heidegger, Lacan, Ricoeur and Foucault, while the last section addresses the science and logic of time as they appear in the works of Guillaume, Einstein, Reichenbach, Prigogine and Barbour. The purpose of the book is threefold: to provide readers with a comprehensive overview of the concept of time in early twentieth-century philosophy; ...

  17. The biological universe. The twentieth century extraterrestrial life debate and the limits of science.

    Science.gov (United States)

    Dick, S. J.

    Throughout the twentieth century, from the furor over Percival Lowell's claim of canals on Mars to the sophisticated Search for Extraterrestrial Intelligence, otherworldly life has often intrigued and occasionally consumed science and the public. Does 'biological law' reign throughout the universe? Are there other histories, religions, and philosophies outside of those on Earth? Do extraterrestrial minds ponder the mysteries of the universe? The attempts to answer these often asked questions form one of the most interesting chapters in the history of science and culture, and this is the first book to provide a rich and colorful history of those attempts during the twentieth century. Covering a broad range of topics, including the search for life in the solar system, the origins of life, UFOs, and aliens in science fiction, the author shows how the concept of extraterrestrial intelligence is a world view of its own, a 'biophysical cosmology' that seeks confirmation no less than physical views of the universe.

  18. The biological universe: the twentieth-century extraterrestrial life debate and the limits of science

    Science.gov (United States)

    Dick, Steven J.

    Throughout the twentieth century, from the furor over Percival Lowell's claim of canals on Mars to the sophisticated Search for Extraterrestrial Intelligence, otherworldly life has often intrigued and occasionally consumed science and the public. Does `biological law' reign throughout the universe? Are there other histories, religions, and philosophies outside of those on Earth? Do extraterrestrial minds ponder the mysteries of the universe? The attempts toanswer these often asked questions form one of the most interesting chapters in the history of science and culture, and The Biological Universe is the first book to provide a rich and colorful history of those attempts during the twentieth century. Covering a broad range of topics, including the search for life in the solar system, the origins of life, UFOs, and aliens in science fiction, Steven J. Dick shows how the concept of extraterrestrial intelligence is a world view of its own, a `biophysical cosmology' that seeks confirmation no less than physical views of the universe.

  19. The Science@NASA Websites

    Science.gov (United States)

    Koczor, Ronald J.; Phillips. Tony; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    The Science@NASA websites represent a significant stride forward in communicating NASA science to the general public via the Internet. Using a family of websites aimed at science-attentive adults, high school students, middle school students and educators, the Science@NASA activity presents selected stories of on-going NASA science, giving context to otherwise dry press releases and scientific reports.

  20. Vegetative propagation of jojoba

    Energy Technology Data Exchange (ETDEWEB)

    Low, C.B.; Hackett, W.P.

    1981-03-01

    Development of jojoba as an economically viable crop requires improved methods of propagation and culture. Rooting experiments were performed on cutting material collected from wild jojoba plants. A striking seasonal fluctuation in rooting potential was found. Jojoba plants can be successfully propagated from stem cuttings made during spring, summer, and, to some extent, fall. Variability among jojoba plants may also play a role in rooting potential, although it is not as important as season. In general, the use of auxin (4,000 ppm indolebutyric acid) on jojoba cuttings during periods of high rooting potential promotes adventitious root formation, but during periods of low rooting potential it has no effect or is even slightly inhibitory. In the greenhouse, cutting-grown plants apparently reproductively matured sooner than those grown from seed. If this observation holds true for plants transplanted into the field, earlier fruit production by cutting--grown plants would mean earlier return of initial planting and maintenance costs.

  1. Propagation of Tau aggregates.

    Science.gov (United States)

    Goedert, Michel; Spillantini, Maria Grazia

    2017-05-30

    Since 2009, evidence has accumulated to suggest that Tau aggregates form first in a small number of brain cells, from where they propagate to other regions, resulting in neurodegeneration and disease. Propagation of Tau aggregates is often called prion-like, which refers to the capacity of an assembled protein to induce the same abnormal conformation in a protein of the same kind, initiating a self-amplifying cascade. In addition, prion-like encompasses the release of protein aggregates from brain cells and their uptake by neighbouring cells. In mice, the intracerebral injection of Tau inclusions induced the ordered assembly of monomeric Tau, followed by its spreading to distant brain regions. Short fibrils constituted the major species of seed-competent Tau. The existence of several human Tauopathies with distinct fibril morphologies has led to the suggestion that different molecular conformers (or strains) of aggregated Tau exist.

  2. Stochastic wave propagation

    CERN Document Server

    Sobczyk, K

    1985-01-01

    This is a concise, unified exposition of the existing methods of analysis of linear stochastic waves with particular reference to the most recent results. Both scalar and vector waves are considered. Principal attention is concentrated on wave propagation in stochastic media and wave scattering at stochastic surfaces. However, discussion extends also to various mathematical aspects of stochastic wave equations and problems of modelling stochastic media.

  3. Bidirectional beam propagation method

    Science.gov (United States)

    Kaczmarski, P.; Lagasse, P. E.

    1988-05-01

    A bidirectional extension of the beam propagation method (BPM) to optical waveguides with a longitudinal discontinuity is presented. The algorithm is verified by computing a reflection of the TE(0) mode from a semiconductor laser facet. The bidirectional BPM is applicable to other configurations such as totally reflecting waveguide mirrors, an abruption transition in a waveguide, or a waveguide with many discontinuities generating multiple reflections. The method can also be adapted to TM polarization.

  4. Gauge engineering and propagators

    Directory of Open Access Journals (Sweden)

    Maas Axel

    2017-01-01

    The dependence of the propagators on the choice of these complete gauge-fixings will then be investigated using lattice gauge theory for Yang-Mills theory. It is found that the implications for the infrared, and to some extent mid-momentum behavior, can be substantial. In going beyond the Yang-Mills case it turns out that the influence of matter can generally not be neglected. This will be briefly discussed for various types of matter.

  5. Urban Forms and Civic Space in Nineteenth to Early Twentieth Century Bangkok and Rangoon

    OpenAIRE

    Moore, Elizabeth Howard; Osiri, Navanath

    2013-01-01

    Buddhist spaces in Bangkok and Rangoon both had long common traditions prior to nineteenth and early twentieth-century colonial incursions. Top–down central city planning with European designs transformed both cities. While Siamese kings personally initiated civic change that began to widen economic and social interaction of different classes, British models segregated European, Burmese, Indian, and Chinese populations to exacerbate social differences. In addition, the Siamese rulers maintain...

  6. An introduction to the poetics of sacred sound in twentieth-century music

    OpenAIRE

    Luigi Antonio Irlandini

    2013-01-01

    Along the twentieth century has occurred the beginning of a fusion between two very different horizons: Western musical composition and Hindu sonic theology. The essential content of this theology and the changes in Western musical language and aesthetics, society and culture which have allowed this fusion to take place are briefly outlined. Instrumental and vocal works by Karlheinz Stockhausen, Giacinto Scelsi, Michael Vetter and David Hykes provide specific examples and, in particular, rais...

  7. The twentieth century was the wettest period in northern Pakistan over the past millennium

    OpenAIRE

    Treydte, K. S.; G. H. Schleser; Gerhard Helle; D. C. Frank; M. Winiger; Haug,G.H.; Esper, J.

    2006-01-01

    Twentieth-century warming could lead to increases in the moisture-holding capacity of the atmosphere, altering the hydrological cycle and the characteristics of precipitation. Such changes in the global rate and distribution of precipitation may have a greater direct effect on human well-being and ecosystem dynamics than changes in temperature itself. Despite the co-variability of both of these climate variables, attention in long-term climate reconstruction has mainly concentrated on tempera...

  8. The Twentieth-Century Sea Level Budget: Recent Progress and Challenges

    Science.gov (United States)

    Jevrejeva, S.; Matthews, A.; Slangen, A.

    2017-01-01

    For coastal areas, given the large and growing concentration of population and economic activity, as well as the importance of coastal ecosystems, sea level rise is one of the most damaging aspects of the warming climate. Huge progress in quantifying the cause of sea level rise and closure of sea level budget for the period since the 1990s has been made mainly due to the development of the global observing system for sea level components and total sea levels. We suggest that a large spread (1.2 ± 0.2-1.9 ± 0.3 mm year-1) in estimates of sea level rise during the twentieth century from several reconstructions demonstrates the need for and importance of the rescue of historical observations from tide gauges, with a focus on the beginning of the twentieth century. Understanding the physical mechanisms contributing to sea level rise and controlling the variability of sea level over the past few 100 years are a challenging task. In this study, we provide an overview of the progress in understanding the cause of sea level rise during the twentieth century and highlight the main challenges facing the interdisciplinary sea level community in understanding the complex nature of sea level changes.

  9. American Influence on Chinese Physics Study in the Early Twentieth Century

    Science.gov (United States)

    Hu, Danian

    2016-01-01

    To save China from the perils she faced in the early twentieth century, the majority of the Chinese seemed to agree that it was necessary to strengthen the country by developing shiye or industry and commerce. For this purpose, they overhauled China's education system and sent a large number of students to study overseas. Many of them enrolled in American colleges, sponsored either by governmental grants or by private funds. As American physics advanced rapidly during the early twentieth century, Chinese physicists studying in top US institutions received first-class professional training. They later went on to become a main driving force in Chinese physics development. The study-in-America programs were apparently more successful than other study-overseas programs. Among other factors, the historical lessons learned from the aborted Chinese Educational Mission in the 1870s, the prevalent and long-time presence of American mission schools in China, and stable public and private funding contributed to their success. American-trained Chinese physicists not only advanced physics study in China but also played leading roles in the development of Chinese science and technology during the twentieth century. This fertile and far-reaching American influence has been embedded in all their accomplishments.

  10. NASA metric transition plan

    Science.gov (United States)

    NASA science publications have used the metric system of measurement since 1970. Although NASA has maintained a metric use policy since 1979, practical constraints have restricted actual use of metric units. In 1988, an amendment to the Metric Conversion Act of 1975 required the Federal Government to adopt the metric system except where impractical. In response to Public Law 100-418 and Executive Order 12770, NASA revised its metric use policy and developed this Metric Transition Plan. NASA's goal is to use the metric system for program development and functional support activities to the greatest practical extent by the end of 1995. The introduction of the metric system into new flight programs will determine the pace of the metric transition. Transition of institutional capabilities and support functions will be phased to enable use of the metric system in flight program development and operations. Externally oriented elements of this plan will introduce and actively support use of the metric system in education, public information, and small business programs. The plan also establishes a procedure for evaluating and approving waivers and exceptions to the required use of the metric system for new programs. Coordination with other Federal agencies and departments (through the Interagency Council on Metric Policy) and industry (directly and through professional societies and interest groups) will identify sources of external support and minimize duplication of effort.

  11. Doing business with NASA

    Science.gov (United States)

    1995-01-01

    Because many U.S. businesses and companies want to do business with NASA, the Agency sends out procurement specialists to trade shows and conferences and organizes seminars to educate the business public on how to get on procurement lists to become product and service providers to the federal government.

  12. NASA Bioreactor Schematic

    Science.gov (United States)

    2001-01-01

    The schematic depicts the major elements and flow patterns inside the NASA Bioreactor system. Waste and fresh medium are contained in plastic bags placed side-by-side so the waste bag fills as the fresh medium bag is depleted. The compliance vessel contains a bladder to accommodate pressure transients that might damage the system. A peristolic pump moves fluid by squeezing the plastic tubing, thus avoiding potential contamination. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  13. My Career at NASA

    Science.gov (United States)

    Dibley, Ryan P.

    2009-01-01

    This viewgraph presentation reviews the work of the presenter at NASA Dryden Flight Research Center. He describes what he does, the projects that he has worked on and the background that led him to his position. The presentation has many pictures of aircraft in flight

  14. NASA Facts, Solar Cells.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    The design and function of solar cells as a source of electrical power for unmanned space vehicles is described in this pamphlet written for high school physical science students. The pamphlet is one of the NASA Facts Science Series (each of which consists of four pages) and is designed to fit in the standard size three-ring notebook. Review…

  15. NASA Ames ATM Research

    Science.gov (United States)

    Denery, Dallas G.

    2000-01-01

    The NASA Ames research Center, in cooperation with the FAA and the industry, has a series of major research efforts underway that are aimed at : 1) improving the flow of traffic in the national airspace system; and 2) helping to define the future air traffic management system. The purpose of this presentation will be to provide a brief summary of some of these activities.

  16. NASA Bioreactor Schematic

    Science.gov (United States)

    2001-01-01

    The schematic depicts the major elements and flow patterns inside the NASA Bioreactor system. Waste and fresh medium are contained in plastic bags placed side-by-side so the waste bag fills as the fresh medium bag is depleted. The compliance vessel contains a bladder to accommodate pressure transients that might damage the system. A peristolic pump moves fluid by squeezing the plastic tubing, thus avoiding potential contamination. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  17. NASA trend analysis procedures

    Science.gov (United States)

    1993-01-01

    This publication is primarily intended for use by NASA personnel engaged in managing or implementing trend analysis programs. 'Trend analysis' refers to the observation of current activity in the context of the past in order to infer the expected level of future activity. NASA trend analysis was divided into 5 categories: problem, performance, supportability, programmatic, and reliability. Problem trend analysis uncovers multiple occurrences of historical hardware or software problems or failures in order to focus future corrective action. Performance trend analysis observes changing levels of real-time or historical flight vehicle performance parameters such as temperatures, pressures, and flow rates as compared to specification or 'safe' limits. Supportability trend analysis assesses the adequacy of the spaceflight logistics system; example indicators are repair-turn-around time and parts stockage levels. Programmatic trend analysis uses quantitative indicators to evaluate the 'health' of NASA programs of all types. Finally, reliability trend analysis attempts to evaluate the growth of system reliability based on a decreasing rate of occurrence of hardware problems over time. Procedures for conducting all five types of trend analysis are provided in this publication, prepared through the joint efforts of the NASA Trend Analysis Working Group.

  18. NASA and Me

    Science.gov (United States)

    Wong, Douglas T.

    2010-01-01

    Topics in this student project report include: biography, NASA history and structure, overview of Johnson Space Center facilities and major projects, and an overview of the Usability Testing and Analysis Facility (UTAF). The UTAF section slides include space habitat evaluations with mockups, crew space vehicle evaluations, and human factors research.

  19. Status of a NASA Standard and Three NASA Handbooks

    Science.gov (United States)

    Kern, Dennis L.

    2011-01-01

    NASA-STD-7003 Pyroshock Test Criteria, May 18, 1999, has been revised per direction of NASA Headquarters to make it a mandatory standard and to update it for advances in the discipline since it's initial release. NASA-HDBK-7004B Force Limited Vibration Testing, January 31, 2003, and NASA-HDBK-7005 Dynamic Environmental Criteria, March 13, 2001, are being updated to reflect advances in the disciplines since their last release. Additionally, a new NASA handbook, NASA-HDBK-7008 Spacecraft Structural Dynamics Testing is currently being prepared. This paper provides an overview of each document, summarizes the major revisions for the documents undergoing update, and provides the development schedules.

  20. NASA Schedule Management Handbook

    Science.gov (United States)

    2011-01-01

    The purpose of schedule management is to provide the framework for time-phasing, resource planning, coordination, and communicating the necessary tasks within a work effort. The intent is to improve schedule management by providing recommended concepts, processes, and techniques used within the Agency and private industry. The intended function of this handbook is two-fold: first, to provide guidance for meeting the scheduling requirements contained in NPR 7120.5, NASA Space Flight Program and Project Management Requirements, NPR 7120.7, NASA Information Technology and Institutional Infrastructure Program and Project Requirements, NPR 7120.8, NASA Research and Technology Program and Project Management Requirements, and NPD 1000.5, Policy for NASA Acquisition. The second function is to describe the schedule management approach and the recommended best practices for carrying out this project control function. With regards to the above project management requirements documents, it should be noted that those space flight projects previously established and approved under the guidance of prior versions of NPR 7120.5 will continue to comply with those requirements until project completion has been achieved. This handbook will be updated as needed, to enhance efficient and effective schedule management across the Agency. It is acknowledged that most, if not all, external organizations participating in NASA programs/projects will have their own internal schedule management documents. Issues that arise from conflicting schedule guidance will be resolved on a case by case basis as contracts and partnering relationships are established. It is also acknowledged and understood that all projects are not the same and may require different levels of schedule visibility, scrutiny and control. Project type, value, and complexity are factors that typically dictate which schedule management practices should be employed.

  1. Wave propagation in elastic solids

    CERN Document Server

    Achenbach, Jan

    1984-01-01

    The propagation of mechanical disturbances in solids is of interest in many branches of the physical scienses and engineering. This book aims to present an account of the theory of wave propagation in elastic solids. The material is arranged to present an exposition of the basic concepts of mechanical wave propagation within a one-dimensional setting and a discussion of formal aspects of elastodynamic theory in three dimensions, followed by chapters expounding on typical wave propagation phenomena, such as radiation, reflection, refraction, propagation in waveguides, and diffraction. The treat

  2. Stochastic model in microwave propagation

    Energy Technology Data Exchange (ETDEWEB)

    Ranfagni, A. [“Nello Carrara” Institute of Applied Physics, CNR Florence Research Area, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Mugnai, D., E-mail: d.mugnai@ifac.cnr.it [“Nello Carrara” Institute of Applied Physics, CNR Florence Research Area, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy)

    2011-11-28

    Further experimental results of delay time in microwave propagation are reported in the presence of a lossy medium (wood). The measurements show that the presence of a lossy medium makes the propagation slightly superluminal. The results are interpreted on the basis of a stochastic (or path integral) model, showing how this model is able to describe each kind of physical system in which multi-path trajectories are present. -- Highlights: ► We present new experimental results on electromagnetic “anomalous” propagation. ► We apply a path integral theoretical model to wave propagation. ► Stochastic processes and multi-path trajectories in propagation are considered.

  3. Temporal scaling in information propagation.

    Science.gov (United States)

    Huang, Junming; Li, Chao; Wang, Wen-Qiang; Shen, Hua-Wei; Li, Guojie; Cheng, Xue-Qi

    2014-06-18

    For the study of information propagation, one fundamental problem is uncovering universal laws governing the dynamics of information propagation. This problem, from the microscopic perspective, is formulated as estimating the propagation probability that a piece of information propagates from one individual to another. Such a propagation probability generally depends on two major classes of factors: the intrinsic attractiveness of information and the interactions between individuals. Despite the fact that the temporal effect of attractiveness is widely studied, temporal laws underlying individual interactions remain unclear, causing inaccurate prediction of information propagation on evolving social networks. In this report, we empirically study the dynamics of information propagation, using the dataset from a population-scale social media website. We discover a temporal scaling in information propagation: the probability a message propagates between two individuals decays with the length of time latency since their latest interaction, obeying a power-law rule. Leveraging the scaling law, we further propose a temporal model to estimate future propagation probabilities between individuals, reducing the error rate of information propagation prediction from 6.7% to 2.6% and improving viral marketing with 9.7% incremental customers.

  4. Temporal scaling in information propagation

    Science.gov (United States)

    Huang, Junming; Li, Chao; Wang, Wen-Qiang; Shen, Hua-Wei; Li, Guojie; Cheng, Xue-Qi

    2014-06-01

    For the study of information propagation, one fundamental problem is uncovering universal laws governing the dynamics of information propagation. This problem, from the microscopic perspective, is formulated as estimating the propagation probability that a piece of information propagates from one individual to another. Such a propagation probability generally depends on two major classes of factors: the intrinsic attractiveness of information and the interactions between individuals. Despite the fact that the temporal effect of attractiveness is widely studied, temporal laws underlying individual interactions remain unclear, causing inaccurate prediction of information propagation on evolving social networks. In this report, we empirically study the dynamics of information propagation, using the dataset from a population-scale social media website. We discover a temporal scaling in information propagation: the probability a message propagates between two individuals decays with the length of time latency since their latest interaction, obeying a power-law rule. Leveraging the scaling law, we further propose a temporal model to estimate future propagation probabilities between individuals, reducing the error rate of information propagation prediction from 6.7% to 2.6% and improving viral marketing with 9.7% incremental customers.

  5. Validity of Parametrized Quark Propagator

    Institute of Scientific and Technical Information of China (English)

    ZHUJi-Zhen; ZHOULi-Juan; MAWei-Xing

    2005-01-01

    Based on an extensively study of the Dyson-Schwinger equations for a fully dressed quark propagator in the “rainbow”approximation, a parametrized fully dressed quark propagator is proposed in this paper. The parametrized propagator describes a confining quark propagator in hadron since it is analytic everywhere in complex p2-plane and has no Lemmann representation. The validity of the new propagator is discussed by comparing its predictions on selfenergy functions A/(p2), Bl(p2) and effective mass M$(p2) of quark with flavor f to their corresponding theoretical results produced by Dyson-Schwinger equations. Our comparison shows that the parametrized quark propagator is a good approximation to the fully dressed quark propagator given by the solutions of Dyson-Schwinger equations in the rainbow approximation and is convenient to use in any theoretical calculations.

  6. Validity of Parametrized Quark Propagator

    Institute of Scientific and Technical Information of China (English)

    ZHU Ji-Zhen; ZHOU Li-Juan; MA Wei-Xing

    2005-01-01

    Based on an extensively study of the Dyson-Schwinger equations for a fully dressed quark propagator in the "rainbow" approximation, a parametrized fully dressed quark propagator is proposed in this paper. The parametrized propagator describes a confining quark propagator in hadron since it is analytic everywhere in complex p2-plane and has no Lemmann representation. The validity of the new propagator is discussed by comparing its predictions on selfenergy functions Af(p2), Bf(p2) and effective mass Mf(p2) of quark with flavor f to their corresponding theoretical results produced by Dyson-Schwinger equations. Our comparison shows that the parametrized quark propagator is a good approximation to the fully dressed quark propagator given by the solutions of Dyson-Schwinger equations in the rainbow approximation and is convenient to use in any theoretical calculations.

  7. PIV uncertainty propagation

    Science.gov (United States)

    Sciacchitano, Andrea; Wieneke, Bernhard

    2016-08-01

    This paper discusses the propagation of the instantaneous uncertainty of PIV measurements to statistical and instantaneous quantities of interest derived from the velocity field. The expression of the uncertainty of vorticity, velocity divergence, mean value and Reynolds stresses is derived. It is shown that the uncertainty of vorticity and velocity divergence requires the knowledge of the spatial correlation between the error of the x and y particle image displacement, which depends upon the measurement spatial resolution. The uncertainty of statistical quantities is often dominated by the random uncertainty due to the finite sample size and decreases with the square root of the effective number of independent samples. Monte Carlo simulations are conducted to assess the accuracy of the uncertainty propagation formulae. Furthermore, three experimental assessments are carried out. In the first experiment, a turntable is used to simulate a rigid rotation flow field. The estimated uncertainty of the vorticity is compared with the actual vorticity error root-mean-square, with differences between the two quantities within 5-10% for different interrogation window sizes and overlap factors. A turbulent jet flow is investigated in the second experimental assessment. The reference velocity, which is used to compute the reference value of the instantaneous flow properties of interest, is obtained with an auxiliary PIV system, which features a higher dynamic range than the measurement system. Finally, the uncertainty quantification of statistical quantities is assessed via PIV measurements in a cavity flow. The comparison between estimated uncertainty and actual error demonstrates the accuracy of the proposed uncertainty propagation methodology.

  8. Ionospheric Radio Propagation

    Science.gov (United States)

    1948-06-25

    applies Chapter 2 presents in simple form the mathe - principles which have been found to work in prac- matical theory underlying the propagation of...6.17, which was described under sec- L713 412 812.111 410.511171IS1&41&716.3 A& tion 6.5 above, and read the value of the muf for muFi .-f------ - 01...twepse, 71. mathe 1measuring virtual 6elghts, is world contour charts. 57; zero distance, 73. Se .1.. Contour chairt MCNiII, A. 0., 106 G Median value

  9. Sequential Back—Propagation

    Institute of Scientific and Technical Information of China (English)

    王晖; 刘大有; 等

    1994-01-01

    In this paper we consider the problem of sequential processing and present a sequential model based on the back-propagation algorithm.This model is intended to deal with intrinsically sequential problems,such as word recognition,speech recognition,natural language understanding.This model can be used to train a network to learn the sequence of input patterns,in a fixed order or a random order.Besides,this model is open- and partial-associative,characterized as “resognizing while accumulating”, which, as we argue, is mental cognition process oriented.

  10. Gear and Transmission Research at NASA Lewis Research Center

    Science.gov (United States)

    Townsend, Dennis P.

    1997-01-01

    This paper is a review of some of the research work of the NASA Lewis Research Center Mechanical Components Branch. It includes a brief review of the NASA Lewis Research Center and the Mechanical Components Branch. The research topics discussed are crack propagation of gear teeth, gear noise of spiral bevel and other gears, design optimization methods, methods we have investigated for transmission diagnostics, the analytical and experimental study of gear thermal conditions, the analytical and experimental study of split torque systems, the evaluation of several new advanced gear steels and transmission lubricants and the evaluation of various aircraft transmissions. The area of research needs for gearing and transmissions is also discussed.

  11. Partnering with NASA: An Overview

    Science.gov (United States)

    Martin, Gary

    2017-01-01

    Partnerships is an important part of doing business at NASA. NASA partners with external organizations to access capabilities under collaborative agreements; enters into agreements for partner access to NASA capabilities; expand overall landscape of space activity; and spurring innovation. NASA partnerships consist of Reimbursable and Non-Reimbursable Space Act Agreements. Partnerships at Ames aligns with Ames' core competencies, and Partners often office in the NASA Research Park, which is an established regional innovation cluster that facilitates commercialization and services as a technology accelerator via onsite collaborations between NASA and its partners.

  12. Light Propagation Volumes

    OpenAIRE

    Mikulica, Tomáš

    2016-01-01

    Cílem diplomové práce je popsat různé metody výpočtu globálního osvětlení scény včetně techniky Light Propagation Volumes. Pro tuto metodu jsou podrobně popsány všechny tři kroky výpočtu: injekce, propagace a vykreslení. Dále je navrženo několik vlastních rozšíření zlepšující grafickou kvalitu metody. Části návrhu a implementace jsou zaměřeny na popis scény, zobrazovacího systému, tvorby stínů, implementace metody Light Propagation Volumes a navržených rozšíření. Práci uzavírá měření, porovná...

  13. NASA Benefits Earth

    Science.gov (United States)

    Robinson, Julie A.

    2009-01-01

    This slide presentation reviews several ways in which NASA research has benefited Earth and made life on Earth better. These innovations include: solar panels, recycled pavement, thermometer pill, invisible braces for straightening teeth, LASIK, aerodynamic helmets and tires for bicycles, cataract detection, technology that was used to remove Anthrax spores from mail handling facilities, study of atomic oxygen erosion of materials has informed the restoration of artwork, macroencapsulation (a potential mechanism to deliver anti cancer drugs to specific sites), and research on a salmonella vaccine. With research on the International Space Station just beginning, there will be opportunities for entrepreneurs and other government agencies to access space for their research and development. As well as NASA continuing its own research on human health and technology development.

  14. NASA's Astrophysics Data Archives

    Science.gov (United States)

    Hasan, H.; Hanisch, R.; Bredekamp, J.

    2000-09-01

    The NASA Office of Space Science has established a series of archival centers where science data acquired through its space science missions is deposited. The availability of high quality data to the general public through these open archives enables the maximization of science return of the flight missions. The Astrophysics Data Centers Coordinating Council, an informal collaboration of archival centers, coordinates data from five archival centers distiguished primarily by the wavelength range of the data deposited there. Data are available in FITS format. An overview of NASA's data centers and services is presented in this paper. A standard front-end modifyer called `Astrowbrowse' is described. Other catalog browsers and tools include WISARD and AMASE supported by the National Space Scince Data Center, as well as ISAIA, a follow on to Astrobrowse.

  15. The NASA Exoplanet Archive

    Science.gov (United States)

    Akeson, Rachel L.; Christiansen, Jessie; Ciardi, David R.; Ramirez, Solange; Schlieder, Joshua; Van Eyken, Julian C.; NASA Exoplanet Archive Team

    2017-01-01

    The NASA Exoplanet Archive supports research and mission planning by the exoplanet community by operating a service providing confirmed and candidate planets, numerous project and contributed data sets and integrated analysis tools. We present the current data contents and functionality of the archive including: interactive tables of confirmed and candidate planetary and stellar properties; Kepler planet candidates, threshold-crossing events, data validation and occurrence rate products; light curves from Kepler, CoRoT, SuperWASP, KELT and other ground-based projects; and spectra and radial velocity data from the literature. Tools provided include a transit ephemeris predictor, light curve viewing utilities, a periodogram service and user-configurable interactive tables. The NASA Exoplanet Archive is funded by NASA’s Exoplanet Exploration Program.

  16. NASA head sworn in

    Science.gov (United States)

    James C. Fletcher was sworn in on May 12, 1986, as administrator of the National Aeronautics and Space Administration (NASA). At a news conference after he was sworn in, Fletcher said that NASA would deal with both its technical problems and its procedural problems before the shuttle will fly again. According to press accounts, he stressed that funds should be made available to replace the Challenger orbiter, which was lost in an explosion on January 28.Fletcher, who had also headed the agency from 1971 to 1977, succeeds James M. Beggs, who was indicted in December 1985 for conspiring to defraud the federal government while serving as a senior executive at the General Dynamics Corporation.

  17. NASA Super Pressure Balloon

    Science.gov (United States)

    Fairbrother, Debbie

    2017-01-01

    NASA is in the process of qualifying the mid-size Super Pressure Balloon (SPB) to provide constant density altitude flight for science investigations at polar and mid-latitudes. The status of the development of the 18.8 million cubic foot SPB capable of carrying one-tone of science to 110,000 feet, will be given. In addition, the operating considerations such as launch sites, flight safety considerations, and recovery will be discussed.

  18. NASA Photo One

    Science.gov (United States)

    Ross, James C.

    2013-01-01

    This is a photographic record of NASA Dryden flight research aircraft, spanning nearly 25 years. The author has served as a Dryden photographer, and now as its chief photographer and airborne photographer. The results are extraordinary images of in-flight aircraft never seen elsewhere, as well as pictures of aircraft from unusual angles on the ground. The collection is the result of the agency required documentation process for its assets.

  19. NASA Bioreactor tissue culture

    Science.gov (United States)

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  20. NASA Bioreactor tissue culture

    Science.gov (United States)

    1998-01-01

    Dr. Lisa E. Freed of the Massachusetts Institute of Technology and her colleagues have reported that initially disc-like specimens tend to become spherical in space, demonstrating that tissues can grow and differentiate into distinct structures in microgravity. The Mir Increment 3 (Sept. 16, 1996 - Jan. 22, 1997) samples were smaller, more spherical, and mechanically weaker than Earth-grown control samples. These results demonstrate the feasibility of microgravity tissue engineering and may have implications for long human space voyages and for treating musculoskeletal disorders on earth. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  1. The NASA Astrobiology Roadmap

    Science.gov (United States)

    Des Marais, David J.; Allamandola, Louis J.; Benner, Steven A.; Boss, Alan P.; Deamer, David; Falkowski, Paul G.; Farmer, Jack D.; Hedges, S. Blair; Jakosky, Bruce M.; Knoll, Andrew H.; Liskowsky, David R.; Meadows, Victoria S.; Meyer, Michael A.; Pilcher, Carl B.; Nealson, Kenneth H.; Spormann, Alfred M.; Trent, Jonathan D.; Turner, William W.; Woolf, Neville J.; Yorke, Harold W.

    2003-01-01

    The NASA Astrobiology Roadmap provides guidance for research and technology development across the NASA enterprises that encompass the space, Earth, and biological sciences. The ongoing development of astrobiology roadmaps embodies the contributions of diverse scientists and technologists from government, universities, and private institutions. The Roadmap addresses three basic questions: How does life begin and evolve, does life exist elsewhere in the universe, and what is the future of life on Earth and beyond? Seven Science Goals outline the following key domains of investigation: understanding the nature and distribution of habitable environments in the universe, exploring for habitable environments and life in our own solar system, understanding the emergence of life, determining how early life on Earth interacted and evolved with its changing environment, understanding the evolutionary mechanisms and environmental limits of life, determining the principles that will shape life in the future, and recognizing signatures of life on other worlds and on early Earth. For each of these goals, Science Objectives outline more specific high-priority efforts for the next 3-5 years. These 18 objectives are being integrated with NASA strategic planning.

  2. The NASA Astrobiology Roadmap.

    Science.gov (United States)

    Des Marais, David J; Nuth, Joseph A; Allamandola, Louis J; Boss, Alan P; Farmer, Jack D; Hoehler, Tori M; Jakosky, Bruce M; Meadows, Victoria S; Pohorille, Andrew; Runnegar, Bruce; Spormann, Alfred M

    2008-08-01

    The NASA Astrobiology Roadmap provides guidance for research and technology development across the NASA enterprises that encompass the space, Earth, and biological sciences. The ongoing development of astrobiology roadmaps embodies the contributions of diverse scientists and technologists from government, universities, and private institutions. The Roadmap addresses three basic questions: how does life begin and evolve, does life exist elsewhere in the universe, and what is the future of life on Earth and beyond? Seven Science Goals outline the following key domains of investigation: understanding the nature and distribution of habitable environments in the universe, exploring for habitable environments and life in our own Solar System, understanding the emergence of life, determining how early life on Earth interacted and evolved with its changing environment, understanding the evolutionary mechanisms and environmental limits of life, determining the principles that will shape life in the future, and recognizing signatures of life on other worlds and on early Earth. For each of these goals, Science Objectives outline more specific high priority efforts for the next three to five years. These eighteen objectives are being integrated with NASA strategic planning.

  3. Three-Dimensional Gear Crack Propagation Studied

    Science.gov (United States)

    Lewicki, David G.

    1999-01-01

    Gears used in current helicopters and turboprops are designed for light weight, high margins of safety, and high reliability. However, unexpected gear failures may occur even with adequate tooth design. To design an extremely safe system, the designer must ask and address the question, "What happens when a failure occurs?" With gear-tooth bending fatigue, tooth or rim fractures may occur. A crack that propagates through a rim will be catastrophic, leading to disengagement of the rotor or propeller, loss of an aircraft, and possible fatalities. This failure mode should be avoided. A crack that propagates through a tooth may or may not be catastrophic, depending on the design and operating conditions. Also, early warning of this failure mode may be possible because of advances in modern diagnostic systems. One concept proposed to address bending fatigue fracture from a safety aspect is a splittooth gear design. The prime objective of this design would be to control crack propagation in a desired direction such that at least half of the tooth would remain operational should a bending failure occur. A study at the NASA Lewis Research Center analytically validated the crack-propagation failsafe characteristics of a split-tooth gear. It used a specially developed three-dimensional crack analysis program that was based on boundary element modeling and principles of linear elastic fracture mechanics. Crack shapes as well as the crack-propagation life were predicted on the basis of the calculated stress intensity factors, mixed-mode crack-propagation trajectory theories, and fatigue crack-growth theories. The preceding figures show the effect of the location of initial cracks on crack propagation. Initial cracks in the fillet of the teeth produced stress intensity factors of greater magnitude (and thus, greater crack growth rates) than those in the root or groove areas of the teeth. Crack growth was simulated in a case study to evaluate crack-propagation paths. Tooth

  4. Workforce Information Cubes for NASA

    Data.gov (United States)

    National Aeronautics and Space Administration — Workforce Information Cubes for NASA, sourced from NASA's personnel/payroll system, gives data about who is working where and on what. Includes records for every...

  5. Commercialization in NASA Space Operations

    Science.gov (United States)

    Gilbert, Charlene E.

    1998-01-01

    Various issues associated with commercialization in NASA space operations are presented in viewgraph form. Specific topics include: 1) NASA's financial outlook; 2) Space operations; 3) Space operations technology; and 4) Strategies associated with these operations.

  6. NASA Engineering Network Lessons Learned

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA Lessons Learned system provides access to official, reviewed lessons learned from NASA programs and projects. These lessons have been made available to the...

  7. NASA Altix 512P SSI

    Science.gov (United States)

    Chan, Davin

    2004-01-01

    This paper presents a general overview of NASA Advances Supercomputing (NAS). The topics include: 1) About NASA Advanced Supercomputing (NAS); 2) System Configuration; 3) Our Experience with the Altix; and 4) Future Plans.

  8. NASA New England Outreach Center

    Science.gov (United States)

    2002-01-01

    The NASA New England Outreach Center in Nashua, New Hampshire was established to serve as a catalyst for heightening regional business awareness of NASA procurement, technology and commercialization opportunities. Emphasis is placed on small business participation, with the highest priority given to small disadvantaged businesses, women-owned businesses, HUBZone businesses, service disabled veteran owned businesses, and historically black colleges and universities and minority institutions. The Center assists firms and organizations to understand NASA requirements and to develop strategies to capture NASA related procurement and technology opportunities. The establishment of the NASA Outreach Center serves to stimulate business in a historically underserved area. NASA direct business awards have traditionally been highly present in the West, Midwest, South, and Southeast areas of the United States. The Center guides and assists businesses and organizations in the northeast to target opportunities within NASA and its prime contractors and capture business and technology opportunities. The Center employs an array of technology access, one-on-one meetings, seminars, site visits, and targeted conferences to acquaint Northeast firms and organizations with representatives from NASA and its prime contractors to learn about and discuss opportunities to do business and access the inventory of NASA technology. This stimulus of interaction also provides firms and organizations the opportunity to propose the use of their developed technology and ideas for current and future requirements at NASA. The Center provides a complement to the NASA Northeast Regional Technology Transfer Center in developing prospects for commercialization of NASA technology. In addition, the Center responds to local requests for assistance and NASA material and documents, and is available to address immediate concerns and needs in assessing opportunities, timely support to interact with NASA Centers on

  9. INSPIRE - Premission. [Interactive NASA Space Physics Ionosphere Radio Experiment

    Science.gov (United States)

    Taylor, William W. L.; Mideke, Michael; Pine, William E.; Ericson, James D.

    1992-01-01

    The Interactive NASA Space Physics Ionosphere Radio Experiment (INSPIRE) designed to assist in a Space Experiments with Particle Accelerators (SEPAC) project is discussed. INSPIRE is aimed at recording data from a large number of receivers on the ground to determine the exact propagation paths and absorption of radio waves at frequencies between 50 Hz and 7 kHz. It is indicated how to participate in the experiment that will involve high school classes, colleges, and amateur radio operators.

  10. Light Front Boson Model Propagation

    Institute of Scientific and Technical Information of China (English)

    Jorge Henrique Sales; Alfredo Takashi Suzuki

    2011-01-01

    stract The scope and aim of this work is to describe the two-body interaction mediated by a particle (either the scalar or the gauge boson) within the light-front formulation. To do this, first of all we point out the importance of propagators and Green functions in Quantum Mechanics. Then we project the covariant quantum propagator onto the light front time to get the propagator for scalar particles in these coordinates. This operator propagates the wave function from x+ = 0 to x+ > O. It corresponds to the definition of the time ordering operation in the light front time x+. We calculate the light-front Green's function for 2 interacting bosons propagating forward in x+. We also show how to write down the light front Green's function from the Feynman propagator and finally make a generalization to N bosons.

  11. NASA Space Human Factors Program

    Science.gov (United States)

    1992-01-01

    This booklet briefly and succinctly treats 23 topics of particular interest to the NASA Space Human Factors Program. Most articles are by different authors who are mainly NASA Johnson or NASA Ames personnel. Representative topics covered include mental workload and performance in space, light effects on Circadian rhythms, human sleep, human reasoning, microgravity effects and automation and crew performance.

  12. NASA Product Peer Review Process

    Science.gov (United States)

    Jenks, Ken

    2009-01-01

    This viewgraph presentation describes NASA's product peer review process. The contents include: 1) Inspection/Peer Review at NASA; 2) Reasons for product peer reviews; 3) Different types of peer reviews; and 4) NASA requirements for peer reviews. This presentation also includes a demonstration of an actual product peer review.

  13. Forced changes to twentieth century ENSO diversity in a last Millennium context

    Science.gov (United States)

    Stevenson, Samantha; Capotondi, Antonietta; Fasullo, John; Otto-Bliesner, Bette

    2017-03-01

    The El Niño/Southern Oscillation (ENSO) exhibits considerable differences between the evolution of individual El Niño and La Niña events (`ENSO diversity'), with significant implications for impacts studies. However, the degree to which external forcing may affect ENSO diversity is not well understood, due to both internal variability and potentially compensatory contributions from multiple forcings. The Community Earth System Model Last Millennium Ensemble (CESM LME) provides an ideal testbed for studying the sensitivity of twentieth century ENSO to forced climate changes, as it contains many realizations of the 850-2005 period with differing combinations of forcings. Metrics of ENSO amplitude and diversity are compared across LME simulations, and although forced changes to ENSO amplitude are generally small, forced changes to diversity are often detectable. Anthropogenic changes to greenhouse gas and ozone/aerosol emissions modify the persistence of Eastern and Central Pacific El Niño events, through shifts in the upwelling and zonal advective feedbacks; these influences generally cancel one another over the twentieth century. Other forcings can also be quite important: land use changes amplify Eastern Pacific El Niño events via modulating zonal advective heating, and orbital forcing tends to preferentially terminate twentieth century Central Pacific El Niño events due to enhanced eastern Pacific cooling during boreal winter and spring. Our results indicate that multiple anthropogenic and natural forcings can have substantial impacts on ENSO diversity, and suggest that correctly representing the net ENSO diversity response to climate change will depend on the precise balance between all these influences.

  14. In Referees We Trust? Controversies over Grant Peer Review in the Late Twentieth Century

    Science.gov (United States)

    Baldwin, Melinda

    While many accounts of external refereeing assume that it has been a consistent part of science since the seventeenth century, the practice developed far more slowly and haphazardly than many observers realize, and it was not until after the Second World War that ''peer review'' became considered an essential part of scientific publishing or grant-making. This talk will explore refereeing procedures at American grant-giving organizations in the twentieth century, focusing especially on the National Science Foundation and the National Institutes of Health. The creators of the NSF and the NIH put refereeing systems in place at their foundation. However, the form and function of these systems differed from modern ''peer review'' in several important ways. At the NSF the initial purpose of the referee process was to advise the NSF program directors, not to dictate funding decisions. At the NIH, small ''study sections'' devoted to particular subjects made recommendations to the NIH leadership, which rendered final judgments. However, beginning in the 1960s a series of controversies about NIH and NSF grants placed refereeing procedures at these organizations under more intense scrutiny. These debates culminated in six days of Special Oversight Hearings into the NSF's peer review process in the summer of 1975. Following the hearings, both the NSF and NIH reformed their review processes to place more emphasis on referees' opinions about grant proposals, making peer review increasingly responsible for decision-making. These controversies illustrate that refereeing continued to undergo significant changes in form and purpose throughout the twentieth century, and further suggest that both the scientific community and the public placed increased emphasis on the role of the referee during the late twentieth century.

  15. Ocean heat content variability in an ensemble of twentieth century ocean reanalyses

    Science.gov (United States)

    de Boisséson, Eric; Balmaseda, Magdalena Alonso; Mayer, Michael

    2017-08-01

    This paper presents a ten-member ensemble of twentieth century Ocean ReAnalyses called ORA-20C. ORA-20C assimilates temperature and salinity profiles and is forced by the ECMWF twentieth century atmospheric reanalysis (ERA-20C) over the 1900-2010 period. This study attempts to identify robust signals of ocean heat content change in ORA-20C and detect contamination by model errors, initial condition uncertainty, surface fluxes and observing system changes. It is shown that ORA-20C trends and variability in the first part of the century result from the surface fluxes and model drift towards a warmer mean state and weak meridional overturning circulation. The impact of the observing system in correcting the mean state causes the deceleration of the warming trend and alters the long-term climate signal. The ensemble spread reflects the long-lasting memory of the initial conditions and the convergence of the system to a solution compatible with surface fluxes, the ocean model and observational constraints. Observations constrain the ocean heat uptake trend in the last decades of the twentieth century, which is similar to trend estimations from the post-satellite era. An ocean heat budget analysis attributes ORA-20C heat content changes to surface fluxes in the first part of the century. The heat flux variability reflects spurious signals stemming from ERA-20C surface fields, which in return result from changes in the atmospheric observing system. The influence of the temperature assimilation increments on the heat budget is growing with time. Increments control the most recent ocean heat uptake signals, highlighting imbalances in forced reanalysis systems in the ocean as well as in the atmosphere.

  16. The Diasporic Dimensions of British Caribbean Federation in the Early Twentieth Century

    Directory of Open Access Journals (Sweden)

    Eric D. Duke

    2009-12-01

    Full Text Available [Second and third pragraph] While much has been written on the significance of British Caribbean activists in various movements associated with black diaspora politics in the twentieth century, particularly their important roles in Pan-African struggles, little has been written on how the various British Caribbean colonies themselves were envisioned among diaspora activists and within the scope of black diaspora politics. Did such Caribbean activists, especially those interested in and connected to diasporic movements beyond the British Caribbean, and their African American and African counterparts forsake the British West Indies as a focus of political engagement for other lands and causes? If not, what was the place of “West Indian liberation” and nation building in the British Caribbean in relation to black diasporic struggles in the early twentieth century? This article address these questions through an examination of how the idea of a united “West Indian nation” (via a federation or closer union among British Caribbean colonies was envisioned within black diaspora politics from the turn of the twentieth century through the 1920s, and the ways in which racial consciousness and motivations informed conceptualizations of such a nation among black political activists of the British Caribbean and other parts of the diaspora. This study argues that efforts to create a federation in the Anglophone Caribbean were much more than simply imperial or regional nation-building projects. Instead, federation was also a diasporic, black nation-building endeavor intricately connected to notions of racial unity, racial uplift, and black self-determination.

  17. Gauge engineering and propagators

    CERN Document Server

    Maas, Axel

    2016-01-01

    Beyond perturbation theory gauge-fixing becomes more involved due to the Gribov-Singer ambiguity: The appearance of additional gauge copies requires to define a procedure how to handle them. For the case of Landau gauge the structure and properties of these additional gauge copies will be investigated. Based on these properties gauge conditions are constructed to account for these gauge copies. The dependence of the propagators on the choice of these complete gauge-fixings will then be investigated using lattice gauge theory for Yang-Mills theory. It is found that the implications for the infrared, and to some extent mid-momentum behavior, can be substantial. In going beyond the Yang-Mills case it turns out that the influence of matter can generally not be neglected. This will be briefly discussed for various types of matter.

  18. Gauge engineering and propagators

    Science.gov (United States)

    Maas, Axel

    2017-03-01

    Beyond perturbation theory gauge-fixing becomes more involved due to the Gribov-Singer ambiguity: The appearance of additional gauge copies requires to define a procedure how to handle them. For the case of Landau gauge the structure and properties of these additional gauge copies will be investigated. Based on these properties gauge conditions are constructed to account for these gauge copies. The dependence of the propagators on the choice of these complete gauge-fixings will then be investigated using lattice gauge theory for Yang-Mills theory. It is found that the implications for the infrared, and to some extent mid-momentum behavior, can be substantial. In going beyond the Yang-Mills case it turns out that the influence of matter can generally not be neglected. This will be briefly discussed for various types of matter.

  19. Counting Belief Propagation

    CERN Document Server

    Kersting, Kristian; Natarajan, Sriraam

    2012-01-01

    A major benefit of graphical models is that most knowledge is captured in the model structure. Many models, however, produce inference problems with a lot of symmetries not reflected in the graphical structure and hence not exploitable by efficient inference techniques such as belief propagation (BP). In this paper, we present a new and simple BP algorithm, called counting BP, that exploits such additional symmetries. Starting from a given factor graph, counting BP first constructs a compressed factor graph of clusternodes and clusterfactors, corresponding to sets of nodes and factors that are indistinguishable given the evidence. Then it runs a modified BP algorithm on the compressed graph that is equivalent to running BP on the original factor graph. Our experiments show that counting BP is applicable to a variety of important AI tasks such as (dynamic) relational models and boolean model counting, and that significant efficiency gains are obtainable, often by orders of magnitude.

  20. Propagators and path integrals

    Energy Technology Data Exchange (ETDEWEB)

    Holten, J.W. van

    1995-08-22

    Path-integral expressions for one-particle propagators in scalar and fermionic field theories are derived, for arbitrary mass. This establishes a direct connection between field theory and specific classical point-particle models. The role of world-line reparametrization invariance of the classical action and the implementation of the corresponding BRST-symmetry in the quantum theory are discussed. The presence of classical world-line supersymmetry is shown to lead to an unwanted doubling of states for massive spin-1/2 particles. The origin of this phenomenon is traced to a `hidden` topological fermionic excitation. A different formulation of the pseudo-classical mechanics using a bosonic representation of {gamma}{sub 5} is shown to remove these extra states at the expense of losing manifest supersymmetry. (orig.).

  1. Study of the Wheeler Propagator

    OpenAIRE

    Bollini, C. G.; Rocca, M. C.

    2010-01-01

    We study the half advanced and half retarded Wheeler Green function and its relation to Feynman propagators. First for massless equation. Then, for Klein-Gordon equations with arbitrary mass parameters; real, imaginary or complex. In all cases the Wheeler propagator lacks an on-shell free propagation. The Wheeler function has support inside the light-cone (whatever the mass). The associated vacuum is symmetric with respect to annihilation and creation operators.

  2. Jane Dawson & Alice Entwistle. A History of Twentieth-Century British Women’s Poetry

    Directory of Open Access Journals (Sweden)

    Rainer EMIG

    2007-06-01

    Full Text Available A gigantic task well executed, this is what Dowson and Entwistle’s book turns out to be. It takes the bull (or should it be the cow, the mad cow of Jo Shapcott’s amusing poems? by the horns and tries to come up with a possible history of the many diverse and often uncollected female voices in Britain in the twentieth century. Dowson and Entwistle’s definition of “British Women’s Poetry” is flexible: “The following poets are British born, published in Britain and/or judged to have made a sign...

  3. Pain: metaphor, body, and culture in Anglo-American societies between the eighteenth and twentieth centuries.

    Science.gov (United States)

    Bourke, Joanna

    2014-10-02

    This article explores the relationship between metaphorical languages, body, and culture, and suggests that such an analysis can reveal a great deal about the meaning and experience of pain in Anglo-American societies between the eighteenth and twentieth centuries. It uses concepts within embodied cognition to speculate on how historians can write a history of sensation. Bodies are actively engaged in the linguistic processes and social interactions that constitute painful sensations. Language is engaged in a dialogue with physiological bodies and social environments. And culture collaborates in the creation of physiological bodies and metaphorical systems.

  4. City-size distributions and the world urban system in the twentieth century.

    Science.gov (United States)

    Ettlinger, N; Archer, J C

    1987-09-01

    "In this paper we trace and interpret changes in the geographical pattern and city-size distribution of the world's largest cities in the twentieth century. Since 1900 the geographical distribution of these cities has become increasingly dispersed; their city-size distribution by rank was nearly linear in 1900 and 1940, and convex in 1980. We interpret the convex distribution which emerged following World War 2 as reflecting an economically integrated but politically and demographically partitioned global urban system. Our interpretation of changes in size distribution of cities emphasizes demographic considerations, largely neglected in previous investigations, including migration and relative rates of population change."

  5. Mid-Twentieth Century Modern Dance in the Twenty-first Century

    OpenAIRE

    Puleio, Dante

    2017-01-01

    Mid-Twentieth Century Modern Dance in the Twenty-First CenturyThe relevance of modern dance being performed today has been a growing topic in the dance field as legacy companies age and the field of contemporary dance continues to expand. This thesis begins with critical response to mid-century modern dance in the work of well-known dance critics John Martin, Edwin Denby and Louis Horst and how they substantiated modern dance’s place in dance history. My interviews with dance critics Alastair...

  6. Pain, sympathy and the medical encounter between the mid eighteenth and the mid twentieth centuries.

    Science.gov (United States)

    Bourke, Joanna

    2012-08-01

    Witnessing people in pain inevitably elicits anxiety in physicians and other caregivers. Physicians are often required to inflict certain types of discomforts in order to alleviate other, more destructive, pains. Accusations that physicians lacked sympathy can be heard throughout the centuries. This article explores the diverse medical responses to such claims between the eighteenth and twentieth centuries. It interrogates changing definitions of clinical sympathy. The concept of sympathy was continually being reworked for each generation of medical professional. Crucially, in this reworking, philosophers (such as Adam Smith) and physicians came into dialogue. Cultures of sympathy were understood in both physiological and metaphorical terms, and were tied to changing notions of professionalization.

  7. [The transparent body: medical imaging and popular culture in the twentieth century].

    Science.gov (United States)

    Ortega, Francisco

    2006-10-01

    In today's societies, successful new medical imaging technologies have focused unprecedented attention on the inside of the human body. These techniques have jumped the walls of the biomedical field per se, penetrating the fields of culture and law. The article traces a genealogy of twentieth-century medical techniques used to visualize the human body and brain, from X-rays to the more sophisticated CTs, MRIs, and PET scans. It explores the changes that these ever more numerous visualization techniques have occasioned in our corporality and examines how these technologies have been received in the courtroom and in popular culture, especially in literature, movies, and magazines.

  8. [Constant or break? On the relations between human genetics and eugenics in the Twentieth Century].

    Science.gov (United States)

    Germann, Pascal

    2015-07-01

    The history of human genetics has been a neglected topic in history of science and medicine for a long time. Only recently, have medical historians begun to pay more attention to the history of human heredity. An important research question deals with the interconnections between human genetics and eugenics. This paper addresses this question: By focusing on a Swiss case study, the investigation of the heredity of goiter, I will argue that there existed close but also ambiguous relations between heredity research and eugenics in the twentieth century. Studies on human heredity often produced evidence that challenged eugenic aims and ideas. Concurrently, however, these studies fostered visions of genetic improvement of human populations.

  9. Body architects in Physical Education and Sports. Among files, skills and knowledge (Argentina early twentieth century

    Directory of Open Access Journals (Sweden)

    Pablo Ariel Scharagrodsky

    2015-09-01

    Full Text Available The following article discusses the creation of two 'skills' with knowledge, procedures, techniques and specific competence when it comes to educate moving bodies: Physical Education teachers and sports doctors in Argentina during the first half of the twentieth century. Starting from the social history of the body (Turner, 1989; Porter, 2003; Vigarello, 2005, this paper focuses its view on knowledge (anthropometry, biometrics and biotypology and procedures (physical bulletins and sports biotypological files used by both 'skills' to identify the ideal types of built corporeality such as the omissions, exclusions and silences that accompanied those body ideals when placing them in their gymnastic, recreational and / or sports 'right place'

  10. BEYOND GUNS AND BUTTER: Finnish Central Government Spending Patterns the in Twentieth Century

    Directory of Open Access Journals (Sweden)

    Jari Eloranta

    2008-01-01

    Full Text Available This paper explains the long-run demand for central government spending in Finland by analyzing quantitative and qualitative changes in the spending behavior, examining possible links between variables in a VAR-framework, and performing multivariate analysis of the demand factors. The results was shoved that a explained  by a lack of military versus social spending tradeoff effect. Even though certain other variables were found to be relevant in explaining this demand, this lack of a tradeoff increased the Finnish spending levels substantially during the twentieth centurt welfare state expansion.

  11. Genesis of home care in Brazil at the start of the twentieth century.

    Science.gov (United States)

    Oliveira, Stefanie Griebeler; Kruse, Maria Henriqueta Luce

    2016-06-01

    Objective to discuss the conditions that enabled home care at the beginning of the twentieth century. Method study of the genealogic inspiration on home care. The empirical material consisted of legal documents on the subject that were published in the Official Journal. The documents were studied using analytical tools, such as Power, Discipline and Biopolitics, which were inspired in Foucault. Results two analytical categories were established, "home inspection: visiting nurses and tuberculosis" and "records: political and economic apparatus". Final considerations tuberculosis, the new profession of visiting nurses, inspection records and the detailed analysis of the cities grant home care a nature of surveillance, inspection and control to conduct the behaviour of individuals.

  12. Pain: metaphor, body, and culture in Anglo-American societies between the eighteenth and twentieth centuries

    Science.gov (United States)

    Bourke, Joanna

    2014-01-01

    This article explores the relationship between metaphorical languages, body, and culture, and suggests that such an analysis can reveal a great deal about the meaning and experience of pain in Anglo-American societies between the eighteenth and twentieth centuries. It uses concepts within embodied cognition to speculate on how historians can write a history of sensation. Bodies are actively engaged in the linguistic processes and social interactions that constitute painful sensations. Language is engaged in a dialogue with physiological bodies and social environments. And culture collaborates in the creation of physiological bodies and metaphorical systems.

  13. The State of Native America at the End of the Twentieth Century

    Directory of Open Access Journals (Sweden)

    J. Kelly Robison

    2007-05-01

    Full Text Available When stereotypes of modern Native Americans are brought forward, these usually manifest themselves in visions of poor Indians living on reservations, which are on lands no one else wanted. Modern Native Americans are often stereotyped as drunks or succumbing to the pressure of gamblers to open their reservations to casinos. One place to start in order to disprove these stereotypes is the statistical data. What follows is not an interpretive essay in the classic scholarly vein, but an informative one that provides a picture of the state of Native America at the end of the Twentieth Century based on current statistical data.

  14. Prof C. N. Yang (Physics Nobel Prize 1957) from Tsinghua University (Beijing) during his CERN Colloquium: "Thematic Melodies of Twentieth Century Theoretical Physics: Quantization, Symmetry and Phase Factor".

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    Prof C. N. Yang (Physics Nobel Prize 1957) from Tsinghua University (Beijing) during his CERN Colloquium: "Thematic Melodies of Twentieth Century Theoretical Physics: Quantization, Symmetry and Phase Factor".

  15. Visual attitude propagation for small satellites

    Science.gov (United States)

    Rawashdeh, Samir A.

    As electronics become smaller and more capable, it has become possible to conduct meaningful and sophisticated satellite missions in a small form factor. However, the capability of small satellites and the range of possible applications are limited by the capabilities of several technologies, including attitude determination and control systems. This dissertation evaluates the use of image-based visual attitude propagation as a compliment or alternative to other attitude determination technologies that are suitable for miniature satellites. The concept lies in using miniature cameras to track image features across frames and extracting the underlying rotation. The problem of visual attitude propagation as a small satellite attitude determination system is addressed from several aspects: related work, algorithm design, hardware and performance evaluation, possible applications, and on-orbit experimentation. These areas of consideration reflect the organization of this dissertation. A "stellar gyroscope" is developed, which is a visual star-based attitude propagator that uses relative motion of stars in an imager's field of view to infer the attitude changes. The device generates spacecraft relative attitude estimates in three degrees of freedom. Algorithms to perform the star detection, correspondence, and attitude propagation are presented. The Random Sample Consensus (RANSAC) approach is applied to the correspondence problem to successfully pair stars across frames while mitigating falsepositive and false-negative star detections. This approach provides tolerance to the noise levels expected in using miniature optics and no baffling, and the noise caused by radiation dose on orbit. The hardware design and algorithms are validated using test images of the night sky. The application of the stellar gyroscope as part of a CubeSat attitude determination and control system is described. The stellar gyroscope is used to augment a MEMS gyroscope attitude propagation

  16. NASA Robotics for Space Exploration

    Science.gov (United States)

    Fischer, RIchard T.

    2007-01-01

    This presentation focuses on NASA's use of robotics in support of space exploration. The content was taken from public available websites in an effort to minimize any ITAR or EAR issues. The agenda starts with an introduction to NASA and the "Vision for Space Exploration" followed by NASA's major areas of robotic use: Robotic Explorers, Astronaut Assistants, Space Vehicle, Processing, and In-Space Workhorse (space infrastructure). Pictorials and movies of NASA robots in use by the major NASA programs: Space Shuttle, International Space Station, current Solar Systems Exploration and Mars Exploration, and future Lunar Exploration are throughout the presentation.

  17. NASA RFID Applications

    Science.gov (United States)

    Fink, Patrick, Ph.D.; Kennedy, Timothy, Ph.D; Powers, Anne; Haridi, Yasser; Chu, Andrew; Lin, Greg; Yim, Hester; Byerly, Kent, Ph.D.; Barton, Richard, Ph.D.; Khayat, Michael, Ph.D.; Studor, George; Brocato, Robert; Ngo, Phong; Arndt, G. D., Ph.D.; Gross, Julia; Phan, Chau; Ni, David, Ph.D.; Dusl, John; Dekome, Kent

    2007-01-01

    This viewgraph document reviews some potential uses for Radio Frequency Identification in space missions. One of these is inventory management in space, including the methods used in Apollo, the Space Shuttle, and Space Station. The potential RFID uses in a remote human outpost are reviewed. The use of Ultra-Wideband RFID for tracking are examined such as that used in Sapphire DART The advantages of RFID in passive, wireless sensors in NASA applications are shown such as: Micrometeoroid impact detection and Sensor measurements in environmental facilities The potential for E-textiles for wireless and RFID are also examined.

  18. NASA Lunar Impact Monitoring

    Science.gov (United States)

    Suggs, Robert M.; Moser, D. E.

    2015-01-01

    The MSFC lunar impact monitoring program began in 2006 in support of environment definition for the Constellation (return to Moon) program. Work continued by the Meteoroid Environment Office after Constellation cancellation. Over 330 impacts have been recorded. A paper published in Icarus reported on the first 5 years of observations and 126 calibrated flashes. Icarus: http://www.sciencedirect.com/science/article/pii/S0019103514002243; ArXiv: http://arxiv.org/abs/1404.6458 A NASA Technical Memorandum on flash locations is in press

  19. Time-dependent corrosion fatique crack propagation in 7000 series aluminum alloys. M.S. Thesis

    Science.gov (United States)

    Mason, Mark E.

    1995-01-01

    The goal of this research is to characterize environmentally assisted subcritical crack growth for the susceptible short-longitudinal orientation of aluminum alloy 7075-T651, immersed in acidified and inhibited NaCl solution. This work is necessary in order to provide a basis for incorporating environmental effects into fatigue crack propagation life prediction codes such as NASA-FLAGRO (NASGRO). This effort concentrates on determining relevant inputs to a superposition model in order to more accurately model environmental fatigue crack propagation.

  20. ONERA-NASA Cooperative Effort on Liner Impedance Eduction

    Science.gov (United States)

    Primus, Julien; Piot, Estelle; Simon, Frank; Jones, Michael G.; Watson, Willie R

    2013-01-01

    As part of a cooperation between ONERA and NASA, the liner impedance eduction methods developed by the two research centers are compared. The NASA technique relies on an objective function built on acoustic pressure measurements located on the wall opposite the test liner, and the propagation code solves the convected Helmholtz equation in uniform ow using a finite element method that implements a continuous Galerkin discretization. The ONERA method uses an objective function based either on wall acoustic pressure or on acoustic velocity acquired above the liner by Laser Doppler Anemometry, and the propagation code solves the linearized Euler equations by a discontinuous Galerkin discretization. Two acoustic liners are tested in both ONERA and NASA ow ducts and the measured data are treated with the corresponding impedance eduction method. The first liner is a wire mesh facesheet mounted onto a honeycomb core, designed to be linear with respect to incident sound pressure level and to grazing ow velocity. The second one is a conventional, nonlinear, perforate-over-honeycomb single layer liner. Configurations without and with ow are considered. For the nonlinear liner, the comparison of liner impedance educed by NASA and ONERA shows a sensitivity to the experimental conditions, namely to the nature of the source and to the sample width.

  1. The NASA SETI program

    Science.gov (United States)

    Billingham, J.; Brocker, D. H.

    1991-01-01

    In 1959, it was proposed that a sensible way to conduct interstellar communication would be to use radio at or near the frequency of hydrogen. In 1960, the first Search for Extraterrestrial Intelligence (SETI) was conducted using a radiotelescope at Green Bank in West Virginia. Since 1970, NASA has systematically developed a definitive program to conduct a sophisticated search for evidence of extraterrestrial intelligent life. The basic hypothesis is that life may be widespread in the univers, and that in many instances extraterrestrial life may have evolved into technological civilizations. The underlying scientific arguments are based on the continuously improving knowledge of astronomy and astrophysics, especially star system formation, and of planetary science, chemical evolution, and biological evolution. If only one in a million sun-like stars in our galaxy harbors species with cognitive intelligence, then there are 100,000 civilizations in the Milky Way alone. The fields of radioastronomy digital electronic engineering, spectrum analysis, and signal detection have advanced rapidly in the last twenty years and now allow for sophisticated systems to be built in order to attempt the detection of extraterrestrial intelligence signals. In concert with the scientific and engineering communities, NASA has developed, over the last several years, a Microwave Observing Project whose goal is to design, build, and operate SETI systems during the decade of the nineties in pursuit of the goal signal detection. The Microwave Observing Project is now approved and underway. There are two major components in the project: the Target Search Element and the Sky Survey Element.

  2. NASA Classroom Bioreactor

    Science.gov (United States)

    Scully, Robert

    2004-01-01

    Exploration of space provides a compelling need for cell-based research into the basic mechanisms that underlie the profound changes that occur in terrestrial life that is transitioned to low gravity environments. Toward that end, NASA developed a rotating bioreactor in which cells are cultured while continuously suspended in a cylinder in which the culture medium rotates with the cylinder. The randomization of the gravity vector accomplished by the continuous rotation, in a low shear environment, provides an analog of microgravity. Because cultures grown in bioreactors develop structures and functions that are much closer to those exhibited by native tissue than can be achieved with traditional culture methods, bioreactors have contributed substantially to advancing research in the fields of cancer, diabetes, infectious disease modeling for vaccine production, drug efficacy, and tissue engineering. NASA has developed a Classroom Bioreactor (CB) that is built from parts that are easily obtained and assembled, user-friendly and versatile. It can be easily used in simple school settings to examine the effect cultures of seeds or cells. An educational brief provides assembly instructions and lesson plans that describes activities in science, math and technology that explore free fall, microgravity, orbits, bioreactors, structure-function relationships and the scientific method.

  3. NASA Classroom Bioreactor

    Science.gov (United States)

    Scully, Robert

    2004-01-01

    Exploration of space provides a compelling need for cell-based research into the basic mechanisms that underlie the profound changes that occur in terrestrial life that is transitioned to low gravity environments. Toward that end, NASA developed a rotating bioreactor in which cells are cultured while continuously suspended in a cylinder in which the culture medium rotates with the cylinder. The randomization of the gravity vector accomplished by the continuous rotation, in a low shear environment, provides an analog of microgravity. Because cultures grown in bioreactors develop structures and functions that are much closer to those exhibited by native tissue than can be achieved with traditional culture methods, bioreactors have contributed substantially to advancing research in the fields of cancer, diabetes, infectious disease modeling for vaccine production, drug efficacy, and tissue engineering. NASA has developed a Classroom Bioreactor (CB) that is built from parts that are easily obtained and assembled, user-friendly and versatile. It can be easily used in simple school settings to examine the effect cultures of seeds or cells. An educational brief provides assembly instructions and lesson plans that describes activities in science, math and technology that explore free fall, microgravity, orbits, bioreactors, structure-function relationships and the scientific method.

  4. Duplessis, rachel blau. Writing beyond the ending: narrative strategies of twentieth - century women writers. bloomington: indiana university press, 1985. Duplessis, rachel blau. Writing beyond the ending: narrative strategies of twentieth - century women writers. bloomington: indiana university press, 1985.

    Directory of Open Access Journals (Sweden)

    Susana Bornéo Funck

    2008-04-01

    Full Text Available Describing her study as "a culturally necessary production of possible meanings," Rachel Blau DuPlessis undertakes a oitical interpretation of twentieth-century women writers in terms of their attempts to "delegitimize the cultural conventions established by a sex-gender system and its values." Describing her study as "a culturally necessary production of possible meanings," Rachel Blau DuPlessis undertakes a oitical interpretation of twentieth-century women writers in terms of their attempts to "delegitimize the cultural conventions established by a sex-gender system and its values."

  5. Continuum mechanics through the ages from the renaissance to the twentieth century : from hydraulics to plasticity

    CERN Document Server

    Maugin, Gérard A

    2016-01-01

    Mixing scientific, historic and socio-economic vision, this unique book complements two previously published volumes on the history of continuum mechanics from this distinguished author. In this volume, Gérard A. Maugin looks at the period from the renaissance to the twentieth century and he includes an appraisal of the ever enduring competition between molecular and continuum modelling views. Chapters trace early works in hydraulics and fluid mechanics not covered in the other volumes and the author investigates experimental approaches, essentially before the introduction of a true concept of stress tensor. The treatment of such topics as the viscoelasticity of solids and plasticity, fracture theory, and the role of geometry as a cornerstone of the field, are all explored. Readers will find a kind of socio-historical appraisal of the seminal contributions by our direct masters in the second half of the twentieth century. The analysis of the teaching and research texts by Duhem, Poincaré and Hilbert on cont...

  6. A social theory of language announced at the threshold of the twentieth century by Antoine Meillet

    Directory of Open Access Journals (Sweden)

    Daniel Marra

    2012-12-01

    Full Text Available Ferdinand de Saussure (1857-1913 defined langue as a social fact, a reality which is exterior to the individual and his will, and belongs to the society. He has never quoted Émile Durkheim (1858-1917 while discussing such concept, however the French sociologist’s conception was widely known in the intellectual milieu of the early twentieth century. Moreover, Antoine Meillet (1866-1936, a disciple of Saussure, while contributing to Durkheim’s newspaper, L’année sociologique (1905-1906, at about the same time that Saussure began the CGL (1907-1911 in Geneva, characterized language as a social fact referring to the concept established by Durkheim. This article deals with the linguistic ideas of Meillet that directly or indirectly influenced a large number of linguists for several decades of the twentieth century. The linguist dedicated himself to both the historical and comparative studies of Indo-European languages, as to the social and historical nature of language. The social aspect of his announced theory is the central theme of this historiographical-linguistic study.

  7. The Development of SONAR as a Tool in Marine Biological Research in the Twentieth Century

    Directory of Open Access Journals (Sweden)

    John A. Fornshell

    2013-01-01

    Full Text Available The development of acoustic methods for measuring depths and ranges in the ocean environment began in the second decade of the twentieth century. The two world wars and the “Cold War” produced three eras of rapid technological development in the field of acoustic oceanography. By the mid-1920s, researchers had identified echoes from fish, Gadus morhua, in the traces from their echo sounders. The first tank experiments establishing the basics for detection of fish were performed in 1928. Through the 1930s, the use of SONAR as a means of locating schools of fish was developed. The end of World War II was quickly followed by the advent of using SONAR to track and hunt whales in the Southern Ocean and the marketing of commercial fish finding SONARs for use by commercial fisherman. The “deep scattering layer” composed of invertebrates and fish was discovered in the late 1940s on the echo sounder records. SONARs employing high frequencies, broadband, split beam, and multiple frequencies were developed as methods for the detection, quantification and identification of fish and invertebrates. The study of fish behavior has seen some use of passive acoustic techniques. Advancements in computer technology have been important throughout the last four decades of the twentieth century.

  8. Spas, mineral waters, and hydrological science in twentieth-century France.

    Science.gov (United States)

    Weisz, G

    2001-09-01

    This essay examines the survival of waters therapy in twentieth-century France with a view to understanding the conditions that make a therapy convincing in one national context and not in another. Part of the explanation for this survival has to do with the size and power of the spa industry. Where this industry was strong and economically powerful--as it was in France--its survival became a national priority. Of equal importance, however, was the role of the medical elite. In twentieth-century France, a small but influential group of elite physicians served as the chief architects of the continued survival and development of water cures. The primary mechanism for this process was a massive and successful campaign to introduce hydrology into the curriculum of medical schools. Once this was achieved, a large corps of academic hydrologists were in a position to produce significant amounts of convincing hydrological science that seemed to demonstrate the varied physiological effects of mineral waters. By the 1940s mineral waters had enough scientific visibility to ensure their inclusion without controversy in the national health insurance system that was being set up.

  9. Labs in the field? Rocky mountain biological stations in the early twentieth century.

    Science.gov (United States)

    Vetter, Jeremy

    2012-01-01

    Biological field stations proliferated in the Rocky Mountains region of the western United States during the early decades of the twentieth century. This essay examines these Rocky Mountain field stations as hybrid lab-field sites from the perspective of the field side of the dichotomy: as field sites with raised walls rather than as laboratories whose walls with the natural world have been lowered. Not only were these field stations transformed to be more like laboratories, but they were also embedded within the particular regional environmental and institutional context of the Rocky Mountains. Using the University of Colorado's Mountain Laboratory at Tolland and other contemporaneous sites as examples, this essay analyzes key features of these sites, including their location within transportation networks, buildings, equipment, personnel, scheduling, recreational and social activities, and other material and social practices on the ground. Considering both the distinctive and shared characteristics of the Rocky Mountain field stations in comparison to other types of field stations provides a more complete picture of the diversity and range of lab-field hybrid sites in the biological sciences in the early twentieth-century United States.

  10. Pronounced differences between observed and CMIP5-simulated multidecadal climate variability in the twentieth century

    Science.gov (United States)

    Kravtsov, Sergey

    2017-06-01

    Identification and dynamical attribution of multidecadal climate undulations to either variations in external forcings or to internal sources is one of the most important topics of modern climate science, especially in conjunction with the issue of human-induced global warming. Here we utilize ensembles of twentieth century climate simulations to isolate the forced signal and residual internal variability in a network of observed and modeled climate indices. The observed internal variability so estimated exhibits a pronounced multidecadal mode with a distinctive spatiotemporal signature, which is altogether absent in model simulations. This single mode explains a major fraction of model-data differences over the entire climate index network considered; it may reflect either biases in the models' forced response or models' lack of requisite internal dynamics, or a combination of both.Plain Language SummaryGlobal and regional warming trends over the course of the twentieth century have been nonuniform, with decadal and longer periods of faster or slower warming, or even cooling. Here we show that state-of-the-art global models used to predict climate fail to adequately reproduce such multidecadal climate variations. In particular, the models underestimate the magnitude of the observed variability and misrepresent its spatial pattern. Therefore, our ability to interpret the observed climate change using these models is limited.

  11. Early twentieth century response of the global atmospheric electric circuit to ENSO

    Science.gov (United States)

    Harrison, G.; Joshi, M.

    2012-04-01

    The global atmospheric electric circuit links charge separation in disturbed weather regions with current flow in the fair weather regions elsewhere. Variations in disturbed weather, such as the changes in lightning associated with Pacific ocean temperature anomalies, can be expected in turn to modify currents flowing in the global atmospheric electric circuit. Strengthening and weakening of the global circuit current has been observed* to follow El Niño and La Niña respectively, from northern hemisphere atmospheric electricity data obtained during the 1970s. Extending this relationship quantitatively into the first half of the twentieth century is pursued here, using surface data from multiple atmospheric electricity observatories including measurements from the southern hemisphere. The independent atmospheric electricity time series from the observatories show similar variations, which is a pre-requisite for inferring global circuit variations from surface measurement. Combining the measurements allows the global circuit sensitivity to ENSO sea surface temperature anomalies to be derived during the earlier part of the twentieth century. * R.G. Harrison, M. Joshi, K. Pascoe, Inferring convective responses to El Niño with atmospheric electricity measurements at Shetland Environ Res Lett 6 (2011) 044028 http://iopscience.iop.org/1748-9326/6/4/044028/

  12. Height convergence and internal migration in mid-twentieth-century Italy.

    Science.gov (United States)

    Lanari, Donatella; Bussini, Odoardo

    2014-01-01

    Height convergence across Italian regions during the second half of the twentieth century is a widely recognized fact. However, it has been suggested that this process was partly affected by the massive migratory flow of people from southern to northern Italy in the 1950s and 1960s, which greatly slowed the height growth rate in the receiving regions, since immigrants were on average shorter than the receiving northern population. The main aims of this study were to estimate the speed of height convergence of Italian military conscripts in the second half of the twentieth century, and to estimate the contribution of internal migration from the south to the north of Italy to height convergence. We hypothesized that migrants from southern Italy reduced height levels among northerners relative to what they would have been without considering migration. We used cohort data on Italian conscripts born in 1951 and 1980. Results indicate that internal migration may explain from 24 to 32.7 percent of height convergence, meaning that ignoring migration flows yields an overestimation of the height changes for conscripts living in the south of Italy.

  13. The riddle of sex: biological theories of sexual difference in the early twentieth-century.

    Science.gov (United States)

    Ha, Nathan Q

    2011-01-01

    At the turn of the twentieth century, biologists such as Oscar Riddle, Thomas Hunt Morgan, Frank Lillie, and Richard Goldschmidt all puzzled over the question of sexual difference, the distinction between male and female. They all offered competing explanations for the biological cause of this difference, and engaged in a fierce debate over the primacy of their respective theories. Riddle propounded a metabolic theory of sex dating from the late-nineteenth century suggesting that metabolism lay at the heart of sexual difference. Thomas Hunt Morgan insisted on the priority of chromosomes, Frank Lillie emphasized the importance of hormones, while Richard Goldschmidt supported a mixed model involving both chromosomes and hormones. In this paper, I will illustrate how the older metabolic theory of sex was displaced when those who argued for the relatively newer theories of chromosomes and hormones gradually formed an alliance that accommodated each other and excluded the metabolic theory of sex. By doing so, proponents of chromosomes and hormones established their authority over the question of sexual difference as they laid the foundations for the new disciplines of genetics and endocrinology. Their debate raised urgent questions about what constituted sexual difference, and how scientists envisioned the plasticity and controllability of this difference. These theories also had immediate political and cultural consequences at the turn of the twentieth century, especially for the eugenic and feminist movements, both of which were heavily invested in knowledge of sex and its determination, ascertainment, and command.

  14. Real Men Wear Uniforms: Photomontage, Postcards, and Military Visual Culture in Early Twentieth-Century Germany

    Directory of Open Access Journals (Sweden)

    Elizabeth Otto

    2012-04-01

    Full Text Available This essay examines early twentieth-century German representations of men and women in uniform to consider how mass culture allowed individuals to participate in aspects of gender construction. It also reveals how masculinity was increasingly linked to military ideals. The pictures under scrutiny here were made in two significant but as yet under-researched types of pictures: pre-avant-garde photomontaged soldier portraits and popular postcards. Both of these visual forms originated in the 1870s, the decade that Germany was itself founded, and they both were in wide circulation by the early twentieth century. Individualized soldier portraits and postcards offered a glorious vision of a man’s military service, and they performed what Theodor Lessing has called Vergemütlichung, the rendering harmless of history. These idealized images of soldierly life were available to a broad swath of the public, but their democratization only extended so far. Representations of women in uniform served to reinforce—through stereotyping and humor—the unquestionably male nature of military institutions and, by extension, of public space. At the same time, by making apparent their own constructed nature, these portraits and postcards offered viewers a glimpse behind the masquerade of masculinity. This essay thus also identifies these images’ links to the subsequent work of avant-garde artists and to the National Socialists’ return to the ideal of uniformed masculinity.

  15. Pioneers of Gentrification: Transformation in Global Neighborhoods in Urban America in the Late Twentieth Century.

    Science.gov (United States)

    Hwang, Jackelyn

    2016-02-01

    Few studies have considered the role of immigration in the rise of gentrification in the late twentieth century. Analysis of U.S. Census and American Community Survey data over 24 years and field surveys of gentrification in low-income neighborhoods across 23 U.S. cities reveal that most gentrifying neighborhoods were "global" in the 1970s or became so over time. An early presence of Asians was positively associated with gentrification; and an early presence of Hispanics was positively associated with gentrification in neighborhoods with substantial shares of blacks and negatively associated with gentrification in cities with high Hispanic growth, where ethnic enclaves were more likely to form. Low-income, predominantly black neighborhoods and neighborhoods that became Asian and Hispanic destinations remained ungentrified despite the growth of gentrification during the late twentieth century. The findings suggest that the rise of immigration after 1965 brought pioneers to many low-income central-city neighborhoods, spurring gentrification in some neighborhoods and forming ethnic enclaves in others.

  16. Surviving the Lunacy Act of 1890: English Psychiatrists and Professional Development during the Early Twentieth Century.

    Science.gov (United States)

    Takabayashi, Akinobu

    2017-04-01

    In recent decades, historians of English psychiatry have shifted their major concerns away from asylums and psychiatrists in the nineteenth century. This is also seen in the studies of twentieth-century psychiatry where historians have debated the rise of psychology, eugenics and community care. This shift in interest, however, does not indicate that English psychiatrists became passive and unimportant actors in the last century. In fact, they promoted Lunacy Law reform for a less asylum-dependent mode of psychiatry, with a strong emphasis on professional development. This paper illustrates the historical dynamics around the professional development of English psychiatry by employing Andrew Abbott's concept of professional development. Abbott redefines professional development as arising from both abstraction of professional knowledge and competition regarding professional jurisdiction. A profession, he suggests, develops through continuous re-formation of its occupational structure, mode of practice and political language in competing with other professional and non-professional forces. In early twentieth-century England, psychiatrists promoted professional development by framing political discourse, conducting a daily trade and promoting new legislation to defend their professional jurisdiction. This professional development story began with the Lunacy Act of 1890, which caused a professional crisis in psychiatry and led to inter-professional competition with non-psychiatric medical service providers. To this end, psychiatrists devised a new political rhetoric, 'early treatment of mental disorder', in their professional interests and succeeded in enacting the Mental Treatment Act of 1930, which re-instated psychiatrists as masters of English psychiatry.

  17. The twentieth century was the wettest period in northern Pakistan over the past millennium

    Science.gov (United States)

    Treydte, Kerstin S.; Schleser, Gerhard H.; Helle, Gerhard; Frank, David C.; Winiger, Matthias; Haug, Gerald H.; Esper, Jan

    2006-04-01

    Twentieth-century warming could lead to increases in the moisture-holding capacity of the atmosphere, altering the hydrological cycle and the characteristics of precipitation. Such changes in the global rate and distribution of precipitation may have a greater direct effect on human well-being and ecosystem dynamics than changes in temperature itself. Despite the co-variability of both of these climate variables, attention in long-term climate reconstruction has mainly concentrated on temperature changes. Here we present an annually resolved oxygen isotope record from tree-rings, providing a millennial-scale reconstruction of precipitation variability in the high mountains of northern Pakistan. The climatic signal originates mainly from winter precipitation, and is robust over ecologically different sites. Centennial-scale variations reveal dry conditions at the beginning of the past millennium and through the eighteenth and early nineteenth centuries, with precipitation increasing during the late nineteenth and the twentieth centuries to yield the wettest conditions of the past 1,000 years. Comparison with other long-term precipitation reconstructions indicates a large-scale intensification of the hydrological cycle coincident with the onset of industrialization and global warming, and the unprecedented amplitude argues for a human role.

  18. Propagation of Ion Acoustic Perturbations

    DEFF Research Database (Denmark)

    Pécseli, Hans

    1975-01-01

    Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered.......Equations describing the propagation of ion acoustic perturbations are considered, using the assumption that the electrons are Boltzman distributed and isothermal at all times. Quasi-neutrality is also considered....

  19. Propagation Engineering in Wireless Communications

    CERN Document Server

    Ghasemi, Abdollah; Ghasemi, Farshid

    2012-01-01

    Wireless communications has seen explosive growth in recent decades, in a realm that is both broad and rapidly expanding to include satellite services, navigational aids, remote sensing, telemetering, audio and video broadcasting, high-speed data communications, mobile radio systems and much more. Propagation Engineering in Wireless Communications deals with the basic principles of radiowaves propagation for frequency bands used in radio-communications, offering descriptions of new achievements and newly developed propagation models. The book bridges the gap between theoretical calculations and approaches, and applied procedures needed for advanced radio links design. The primary objective of this two-volume set is to demonstrate the fundamentals, and to introduce propagation phenomena and mechanisms that engineers are likely to encounter in the design and evaluation of radio links of a given type and operating frequency. Volume one covers basic principles, along with tropospheric and ionospheric propagation,...

  20. View-based Propagator Derivation

    CERN Document Server

    Schulte, Christian

    2009-01-01

    When implementing a propagator for a constraint, one must decide about variants: When implementing min, should one also implement max? Should one implement linear constraints both with unit and non-unit coefficients? Constraint variants are ubiquitous: implementing them requires considerable (if not prohibitive) effort and decreases maintainability, but will deliver better performance than resorting to constraint decomposition. This paper shows how to use views to derive perfect propagator variants. A model for views and derived propagators is introduced. Derived propagators are proved to be indeed perfect in that they inherit essential properties such as correctness and domain and bounds consistency. Techniques for systematically deriving propagators such as transformation, generalization, specialization, and type conversion are developed. The paper introduces an implementation architecture for views that is independent of the underlying constraint programming system. A detailed evaluation of views implement...

  1. Directed HK propagator

    Science.gov (United States)

    Kocia, Lucas; Heller, Eric J.

    2015-09-01

    We offer a more formal justification for the successes of our recently communicated "directed Heller-Herman-Kluk-Kay" (DHK) time propagator by examining its performance in one-dimensional bound systems which exhibit at least quasi-periodic motion. DHK is distinguished by its single one-dimensional integral—a vast simplification over the usual 2N-dimensional integral in full Heller-Herman-Kluk-Kay (for an N-dimensional system). We find that DHK accurately captures particular coherent state autocorrelations when its single integral is chosen to lie along these states' fastest growing manifold, as long as it is not perpendicular to their action gradient. Moreover, the larger the action gradient, the better DHK will perform. We numerically examine DHK's accuracy in a one-dimensional quartic oscillator and illustrate that these conditions are frequently satisfied such that the method performs well. This lends some explanation for why DHK frequently seems to work so well and suggests that it may be applicable to systems exhibiting quite strong anharmonicity.

  2. Range Information Propagation Transform

    Institute of Scientific and Technical Information of China (English)

    陈向荣; 朱志刚; 等

    1998-01-01

    A novel method of model-based object recognition is presented in this paper.Its novelty stems from the fact that the gray level image captured by a camera is merged with sparse range information in an active manner.By using a projective transform, which is determined by the sparse range data,festures(e.g.edge points)related to a single planar surface patch of figure in the scene can be assignew with their corresponding range values respectively.As a result,the shape of the very planar patch or figure can be recovered and various kinds of description in the Euclidean space can be calculated.Based on these descriptions values,the hypothesis about the identification of the object and its pose in space can be obtained with a high probability of success,and a high efficiency of hypothesis-verification process can be expected.Another advantage of this method is that the edge detection process can be navigated to the proper location hinted by the sparse range image.In consequence edge features can be extracted even in the regions with low contrast.In this paper the principle of range information propagation transform(RIPT)is explained,and some implementation issues,such as the algorithms using calibrated or uncalibrated gray level image for object recognition,are discussed.The preliminary experimental results are presented to indicate the effectiveness and efficiency of the proposed method.

  3. The NASA Fireball Network

    Science.gov (United States)

    Cooke, William J.

    2013-01-01

    In the summer of 2008, the NASA Meteoroid Environments Office (MEO) began to establish a video fireball network, based on the following objectives: (1) determine the speed distribution of cm size meteoroids, (2) determine the major sources of cm size meteoroids (showers/sporadic sources), (3) characterize meteor showers (numbers, magnitudes, trajectories, orbits), (4) determine the size at which showers dominate the meteor flux, (5) discriminate between re-entering space debris and meteors, and 6) locate meteorite falls. In order to achieve the above with the limited resources available to the MEO, it was necessary that the network function almost fully autonomously, with very little required from humans in the areas of upkeep or analysis. With this in mind, the camera design and, most importantly, the ASGARD meteor detection software were adopted from the University of Western Ontario's Southern Ontario Meteor Network (SOMN), as NASA has a cooperative agreement with Western's Meteor Physics Group. 15 cameras have been built, and the network now consists of 8 operational cameras, with at least 4 more slated for deployment in calendar year 2013. The goal is to have 15 systems, distributed in two or more groups east of automatic analysis; every morning, this server also automatically generates an email and a web page (http://fireballs.ndc.nasa.gov) containing an automated analysis of the previous night's events. This analysis provides the following for each meteor: UTC date and time, speed, start and end locations (longitude, latitude, altitude), radiant, shower identification, light curve (meteor absolute magnitude as a function of time), photometric mass, orbital elements, and Tisserand parameter. Radiant/orbital plots and various histograms (number versus speed, time, etc) are also produced. After more than four years of operation, over 5,000 multi-station fireballs have been observed, 3 of which potentially dropped meteorites. A database containing data on all

  4. 1995 NASA High-Speed Research Program Sonic Boom Workshop. Volume 2; Configuration Design, Analysis, and Testing

    Science.gov (United States)

    Baize, Daniel G. (Editor)

    1999-01-01

    The High-Speed Research Program and NASA Langley Research Center sponsored the NASA High-Speed Research Program Sonic Boom Workshop on September 12-13, 1995. The workshop was designed to bring together NASAs scientists and engineers and their counterparts in industry, other Government agencies, and academia working together in the sonic boom element of NASAs High-Speed Research Program. Specific objectives of this workshop were to: (1) report the progress and status of research in sonic boom propagation, acceptability, and design; (2) promote and disseminate this technology within the appropriate technical communities; (3) help promote synergy among the scientists working in the Program; and (4) identify technology pacing, the development C, of viable reduced-boom High-Speed Civil Transport concepts. The Workshop was organized in four sessions: Sessions 1 Sonic Boom Propagation (Theoretical); Session 2 Sonic Boom Propagation (Experimental); Session 3 Acceptability Studies-Human and Animal; and Session 4 - Configuration Design, Analysis, and Testing.

  5. NASA, the Fisherman's Friend

    Science.gov (United States)

    2005-01-01

    Every angler has his secrets, whether it be an old family recipe for stink bait, a midnight worm-hunting ritual, or the most coveted of all, the no-fail fishing hole. Most of these secrets are lore and legend, passed through generations, and coveted more than the family s best tableware. Each of these kernels of wisdom promises the fisherman a bite at the end of the line, but very few are rooted in fact and science. There is one, though.... NASA partnered with a company on the bayous of Mississippi and Louisiana to use satellite data to create a marine information system, a space-age fish finder. This product provides up-to-date information about the location of a variety of fish, including yellowfin tuna, bluefish, blue marlin, white marlin, sailfish, blackfin tuna, little tunny, and swordfish. The system shows peaked catch rates, and may be the only true fish-finding product on the market.

  6. NASA, Building Tomorrow's Future

    Science.gov (United States)

    Mango, Edward

    2011-01-01

    We, as NASA, continue to Dare Mighty Things. Here we are in October. In my country, the United States of America, we celebrate the anniversary of Christopher Columbus's arrival in the Americas, which occurred on October 12, 1492. His story, although happening over 500 years ago, is still very valid today. It is a part of the American spirit; part of the international human spirit. Columbus is famous for discovering the new world we now call America, but he probably never envisioned what great discoveries would be revealed many generations later. But in order for Columbus to begin his great adventure, he needed a business plan. Ho would he go about obtaining the funds and support necessary to build, supply, and man the ships required for his travels? He had a lot of obstacles and distractions. He needed a strong, internal drive to achieve his plans and recruit a willing crew of explorers also ready to risk their all for the unknown journey ahead. As Columbus set sail, he said "By prevailing over all obstacles and distractions, one may unfailingly arrive at his chosen goal or destination." Columbus may not have known he was on a journey for all human exploration. Recently, Charlie Bolden, the NASA Administrator, said, "Human exploration is and has always been about making life better for humans on Earth." Today, NASA and the U.S. human spaceflight program hold many of the same attributes as did Columbus and his contemporaries - a willing, can-do spirit. We are on the threshold of exciting new times in space exploration. Like Columbus, we need a business plan to take us into the future. We need to design the best ships and utilize the best designers, with their past knowledge and experience, to build those ships. We need funding and support from governments to achieve these goals of space exploration into the unknown. NASA does have that business plan, and it is an ambitious plan for human spaceflight and exploration. Today, we have a magnificent spaceflight

  7. NASA: Biomedical applications team

    Science.gov (United States)

    1981-01-01

    The status of projects involving the adaptation of NASA technologies for medical purposes is reviewed. Devices for the measurement of joint deformation of arthritic hands, the development of an artificial pancreas, provision of an auditory signal to avert epileptic seizures, are described along with the control of medication levels, a compressed air tank to supply power for field dentistry, and an electroencephalogram monitor. The use of the Lixiscope as a portable fluoroscope, thermal laminates for hand and foot warmers for patients with Raynaud's syndrome, and the use of absorptive coatings for instruments for controlling medication levels are described. The applicability of occupation health and safety practices to industry, computerized patient scheduling, impregnation of the common facial tissue with an agent for killing respiratory viruses, commercial applications of anthropometric data, and multispectral image analysis of the skin as a diagnostic tool are reviewed.

  8. NASA priority technologies

    Science.gov (United States)

    Sadin, S. R.; Slone, H. O.

    1983-01-01

    Significant research areas deserving of attention within the NASA Space Research and Technology program are discussed, noting that the program is pursed to strengthen the U.S. technology base, improve low-cost access to space, and to aid in the expanded use of space, including a space station. Study areas being pursued include new Orbiter thermal protection system materials, developing longer-life reusable engines, and providing the technology for orbital transfer vehicle propulsion and aeroassisted braking. Attention is also being given to CFD techniques for entry body and rocket engine design, verifying the feasibility of advanced sensor concepts, defining the technology for large deployable RF antennas, and improving on-board data management systems. Of particular concern is to establish technologies which will enhance and extend a permanent manned presence in space.

  9. NASA Space Life Sciences

    Science.gov (United States)

    Hayes, Judith

    2009-01-01

    This slide presentation reviews the requirements that NASA has for the medical service of a crew returning to earth after long duration space flight. The scenarios predicate a water landing. Two scenarios are reviewed that outline the ship-board medical operations team and the ship board science reseach team. A schedule for the each crew upon landing is posited for each of scenarios. The requirement for a heliport on board the ship is reviewed and is on the requirement for a helicopter to return the Astronauts to the Baseline Data Collection Facility (BDCF). The ideal is to integrate the medical and science requirements, to minimize the risks and Inconveniences to the returning astronauts. The medical support that is required for all astronauts returning from long duration space flight (30 days or more) is reviewed. The personnel required to support the team is outlined. The recommendations for medical operations and science research for crew support are stated.

  10. NASA Technology Benefits Orthotics

    Science.gov (United States)

    Myers, Neill; Shadoan, Michael

    1998-01-01

    Engineers at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama have designed a knee brace to aid in the rehabilitation of medical patients. The device, called the Selectively Lockable Knee Brace, was designed for knee injury and stroke patients but may potentially serve in many more patient applications. Individuals with sports related injuries, spinal cord injuries and birth defects, such as spina bifida, may also benefit from the device. The Selectively Lockable Knee Brace is designed to provide secure support to the patient when weight is applied to the leg; however; when the leg is not supporting weight, the device allows free motion of the knee joint. Braces currently on the market lock the knee in a rigid, straight or bent position, or by manually pulling a pin, allow continuous free joint motion.

  11. Configuration Management at NASA

    Science.gov (United States)

    Doreswamy, Rajiv

    2013-01-01

    NASA programs are characterized by complexity, harsh environments and the fact that we usually have one chance to get it right. Programs last decades and need to accept new hardware and technology as it is developed. We have multiple suppliers and international partners Our challenges are many, our costs are high and our failures are highly visible. CM systems need to be scalable, adaptable to new technology and span the life cycle of the program (30+ years). Multiple Systems, Contractors and Countries added major levels of complexity to the ISS program and CM/DM and Requirements management systems center dot CM Systems need to be designed for long design life center dot Space Station Design started in 1984 center dot Assembly Complete in 2012 center dot Systems were developed on a task basis without an overall system perspective center dot Technology moves faster than a large project office, try to make sure you have a system that can adapt

  12. NASA Biological Specimen Repository

    Science.gov (United States)

    McMonigal, K. A.; Pietrzyk, R. A.; Sams, C. F.; Johnson, M. A.

    2010-01-01

    The NASA Biological Specimen Repository (NBSR) was established in 2006 to collect, process, preserve and distribute spaceflight-related biological specimens from long duration ISS astronauts. This repository provides unique opportunities to study longitudinal changes in human physiology spanning may missions. The NBSR collects blood and urine samples from all participating ISS crewmembers who have provided informed consent. These biological samples are collected once before flight, during flight scheduled on flight days 15, 30, 60, 120 and within 2 weeks of landing. Postflight sessions are conducted 3 and 30 days after landing. The number of in-flight sessions is dependent on the duration of the mission. Specimens are maintained under optimal storage conditions in a manner that will maximize their integrity and viability for future research The repository operates under the authority of the NASA/JSC Committee for the Protection of Human Subjects to support scientific discovery that contributes to our fundamental knowledge in the area of human physiological changes and adaptation to a microgravity environment. The NBSR will institute guidelines for the solicitation, review and sample distribution process through establishment of the NBSR Advisory Board. The Advisory Board will be composed of representatives of all participating space agencies to evaluate each request from investigators for use of the samples. This process will be consistent with ethical principles, protection of crewmember confidentiality, prevailing laws and regulations, intellectual property policies, and consent form language. Operations supporting the NBSR are scheduled to continue until the end of U.S. presence on the ISS. Sample distribution is proposed to begin with selections on investigations beginning in 2017. The availability of the NBSR will contribute to the body of knowledge about the diverse factors of spaceflight on human physiology.

  13. NASA Bluetooth Wireless Communications

    Science.gov (United States)

    Miller, Robert D.

    2007-01-01

    NASA has been interested in wireless communications for many years, especially when the crew size of the International Space Station (ISS) was reduced to two members. NASA began a study to find ways to improve crew efficiency to make sure the ISS could be maintained with limited crew capacity and still be a valuable research testbed in Low-Earth Orbit (LEO). Currently the ISS audio system requires astronauts to be tethered to the audio system, specifically a device called the Audio Terminal Unit (ATU). Wireless communications would remove the tether and allow astronauts to freely float from experiment to experiment without having to worry about moving and reconnecting the associated cabling or finding the space equivalent of an extension cord. A wireless communication system would also improve safety and reduce system susceptibility to Electromagnetic Interference (EMI). Safety would be improved because a crewmember could quickly escape a fire while maintaining communications with the ground and other crewmembers at any location. In addition, it would allow the crew to overcome the volume limitations of the ISS ATU. This is especially important to the Portable Breathing Apparatus (PBA). The next generation of space vehicles and habitats also demand wireless attention. Orion will carry up to six crewmembers in a relatively small cabin. Yet, wireless could become a driving factor to reduce launch weight and increase habitable volume. Six crewmembers, each tethered to a panel, could result in a wiring mess even in nominal operations. In addition to Orion, research is being conducted to determine if Bluetooth is appropriate for Lunar Habitat applications.

  14. NASA Integrated Network COOP

    Science.gov (United States)

    Anderson, Michael L.; Wright, Nathaniel; Tai, Wallace

    2012-01-01

    Natural disasters, terrorist attacks, civil unrest, and other events have the potential of disrupting mission-essential operations in any space communications network. NASA's Space Communications and Navigation office (SCaN) is in the process of studying options for integrating the three existing NASA network elements, the Deep Space Network, the Near Earth Network, and the Space Network, into a single integrated network with common services and interfaces. The need to maintain Continuity of Operations (COOP) after a disastrous event has a direct impact on the future network design and operations concepts. The SCaN Integrated Network will provide support to a variety of user missions. The missions have diverse requirements and include anything from earth based platforms to planetary missions and rovers. It is presumed that an integrated network, with common interfaces and processes, provides an inherent advantage to COOP in that multiple elements and networks can provide cross-support in a seamless manner. The results of trade studies support this assumption but also show that centralization as a means of achieving integration can result in single points of failure that must be mitigated. The cost to provide this mitigation can be substantial. In support of this effort, the team evaluated the current approaches to COOP, developed multiple potential approaches to COOP in a future integrated network, evaluated the interdependencies of the various approaches to the various network control and operations options, and did a best value assessment of the options. The paper will describe the trade space, the study methods, and results of the study.

  15. Dike Propagation Near Drifts

    Energy Technology Data Exchange (ETDEWEB)

    NA

    2002-03-04

    The purpose of this Analysis and Model Report (AMR) supporting the Site Recommendation/License Application (SR/LA) for the Yucca Mountain Project is the development of elementary analyses of the interactions of a hypothetical dike with a repository drift (i.e., tunnel) and with the drift contents at the potential Yucca Mountain repository. This effort is intended to support the analysis of disruptive events for Total System Performance Assessment (TSPA). This AMR supports the Process Model Report (PMR) on disruptive events (CRWMS M&O 2000a). This purpose is documented in the development plan (DP) ''Coordinate Modeling of Dike Propagation Near Drifts Consequences for TSPA-SR/LA'' (CRWMS M&O 2000b). Evaluation of that Development Plan and the work to be conducted to prepare Interim Change Notice (ICN) 1 of this report, which now includes the design option of ''Open'' drifts, indicated that no revision to that DP was needed. These analyses are intended to provide reasonable bounds for a number of expected effects: (1) Temperature changes to the waste package from exposure to magma; (2) The gas flow available to degrade waste containers during the intrusion; (3) Movement of the waste package as it is displaced by the gas, pyroclasts and magma from the intruding dike (the number of packages damaged); (4) Movement of the backfill (Backfill is treated here as a design option); (5) The nature of the mechanics of the dike/drift interaction. These analyses serve two objectives: to provide preliminary analyses needed to support evaluation of the consequences of an intrusive event and to provide a basis for addressing some of the concerns of the Nuclear Regulatory Commission (NRC) expressed in the Igneous Activity Issue Resolution Status Report.

  16. NASA and The Semantic Web

    Science.gov (United States)

    Ashish, Naveen

    2005-01-01

    We provide an overview of several ongoing NASA endeavors based on concepts, systems, and technology from the Semantic Web arena. Indeed NASA has been one of the early adopters of Semantic Web Technology and we describe ongoing and completed R&D efforts for several applications ranging from collaborative systems to airspace information management to enterprise search to scientific information gathering and discovery systems at NASA.

  17. W/V-Band RF Propagation Experiment Design

    Science.gov (United States)

    Acosta, Roberto J.; Nessel, James A.; Simons, Rainee N.; Zemba, Michael J.; Morse, Jacquelynne Rose; Budinger, James M.

    2012-01-01

    The utilization of frequency spectrum for space-to-ground communications applications has generally progressed from the lowest available bands capable of supporting transmission through the atmosphere to the higher bands, which have required research and technological advancement to implement. As communications needs increase and the available spectrum in the microwave frequency bands (3 30 GHz) becomes congested globally, future systems will move into the millimeter wave (mm-wave) range (30 300 GHz). While current systems are operating in the Ka-band (20 30 GHz), systems planned for the coming decades will initiate operations in the Q-Band (33 50 GHz), V-Band (50 75 GHz) and W Band (75 110 GHz) of the spectrum. These bands offer extremely broadband capabilities (contiguous allocations of 500 MHz to 1GHz or more) and an uncluttered spectrum for a wide range of applications. NASA, DoD and commercial missions that can benefit from moving into the mm-wave bands include data relay and near-Earth data communications, unmanned aircraft communications, NASA science missions, and commercial broadcast/internet services, all able to be implemented via very small terminals. NASA Glenn Research Center has a long history of performing the inherently governmental function of opening new frequency spectrum by characterizing atmospheric effects on electromagnetic propagation and collaborating with the satellite communication industry to develop specific communications technologies for use by NASA and the nation. Along these lines, there are critical issues related to W/V-band propagation that need to be thoroughly understood before design of any operational system can commence. These issues arise primarily due to the limitations imposed on W/V-band signal propagation by the Earth s atmosphere, and to the fundamental lack of understanding of these effects with regards to proper system design and fade mitigation. In this paper, The GRC RF propagation team recommends measurements

  18. Laser beam propagation generation and propagation of customized light

    CERN Document Server

    Forbes, Andrew

    2014-01-01

    ""The text is easy to read and is accompanied by beautiful illustrations. It is an excellent book for anyone working in laser beam propagation and an asset for any library.""-Optics & Photonics News, July 2014

  19. NASA space biology accomplishments, 1982

    Science.gov (United States)

    Halstead, T. W.; Pleasant, L. G.

    1983-01-01

    Summaries of NASA's Space Biology Program projects are provided. The goals, objectives, accomplishments, and future plans of each project are described in this publication as individual technical summaries.

  20. ‘Canonization in early twentieth-century Chinese art history’

    Directory of Open Access Journals (Sweden)

    Guo Hui

    2014-06-01

    Full Text Available Since the 1980s, the discussion of canons has been a dominant theme in the discipline of Western art history. Various concerns have emerged regarding ‘questions of artistic judgment’, ‘the history genesis of masterpieces’, ‘variations in taste’, ‘the social instruments of canonicity’, and ‘how canons disappear’. Western art historians have considered how the canon’s appearance in Western visual art embodies aesthetic, ideological, cultural, social, and symbolic values. In Chinese art history, the idea of a canon including masterpieces, important artists, and forms of art, dates back to the mid ninth century when Zhang Yanyuan wrote his painting history Record of Famous Painters of All the Dynasties. Faced with quite different political, economic, and social conditions amid the instability of the early twentieth century, Chinese scholars attempted to discover new canons for cultural orthodoxy and authority. Modern means for canonization, such as museums and exhibition displays, cultural and academic institutions, and massive art publications with image reproduction in good quality, brought the process up to an unprecedented speed. It is true that most of these means have comparable counterparts in pre-modern times. However, their enormous scope and overwhelming influence are far beyond the reach of their imperial counterparts. Through an inter-textual reading of the publications on Chinese art history in early twentieth-century China, this paper explores the transformation of canons in order to shed light on why and how canonical formation happened during the Republican period of China. Despite the diverse styles and strategies which Chinese writers used in their narratives, Chinese art historical books produced during the Republican period canonized and de-canonized artworks. In this paper, the discussion of these texts, with reference to other art historical works, comprises three parts: 1 canon formation of artistic forms

  1. Radial propagators and Wilson loops

    CERN Document Server

    Leupold, S; Leupold, Stefan; Weigert, Heribert

    1996-01-01

    We present a relation which connects the propagator in the radial (Fock-Schwinger) gauge with a gauge invariant Wilson loop. It is closely related to the well-known field strength formula and can be used to calculate the radial gauge propagator. The result is shown to diverge in four-dimensional space even for free fields, its singular nature is however naturally explained using the renormalization properties of Wilson loops with cusps and self-intersections. Using this observation we provide a consistent regularization scheme to facilitate loop calculations. Finally we compare our results with previous approaches to derive a propagator in Fock-Schwinger gauge.

  2. Particle propagation in cosmological backgrounds

    CERN Document Server

    Arteaga, Daniel

    2007-01-01

    We study the quantum propagation of particles in cosmological backgrounds, by considering a doublet of massive scalar fields propagating in an expanding universe, possibly filled with radiation. We focus on the dissipative effects related to the expansion rate. At first order, we recover the expected result that the decay rate is determined by the local temperature. Beyond linear order, the decay rate has an additional contribution governed by the expansion parameter. This latter contribution is present even for stable particles in the vacuum. Finally, we analyze the long time behaviour of the propagator and briefly discuss applications to the trans-Planckian question.

  3. Light Propagation For Accelerated Observers

    CERN Document Server

    Adewole, A I A

    2001-01-01

    We show that for an observer in translational, rotational or gravitational motion, a linearly polarized plane wave has two modes of propagation in a stationary, homogeneous and isotropic medium according to Hertz's version of Maxwell's theory. The first mode is characterized by polarization at right angles to the direction of propagation and has a phase velocity that is controlled by the material constants of the medium. The second mode is characterized by polarization along the propagation direction and has a phase velocity that is controlled by the motion of the observer. We outline some applications of the second mode in emerging technologies.

  4. TSUNAMI WAVE PROPAGATION ALONG WAVEGUIDES

    Directory of Open Access Journals (Sweden)

    Andrei G. Marchuk

    2009-01-01

    Full Text Available This is a study of tsunami wave propagation along the waveguide on a bottom ridge with flat sloping sides, using the wave rays method. During propagation along such waveguide the single tsunami wave transforms into a wave train. The expression for the guiding velocities of the fastest and slowest signals is defined. The tsunami wave behavior above the ocean bottom ridges, which have various model profiles, is investigated numerically with the help of finite difference method. Results of numerical experiments show that the highest waves are detected above a ridge with flat sloping sides. Examples of tsunami propagation along bottom ridges of the Pacific Ocean are presented.

  5. Did the 1918 influenza cause the twentieth century cardiovascular mortality epidemic in the United States?

    Directory of Open Access Journals (Sweden)

    Steven Tate

    2016-10-01

    Full Text Available During most of the twentieth century, cardiovascular mortality increased in the United States while other causes of death declined. By 1958, the age-standardized death rate (ASDR for cardiovascular causes for females was 1.84 times that for all other causes, combined (and, for males, 1.79×. Although contemporary observers believed that cardiovascular mortality would remain high, the late 1950s and early 1960s turned out to be the peak of a roughly 70-year epidemic. By 1988 for females (1986 for males, a spectacular decline had occurred, wherein the ASDR for cardiovascular causes was less than that for other causes combined. We discuss this phenomenon from a demographic point of view. We also test a hypothesis from the literature, that the 1918 influenza pandemic caused the cardiovascular mortality epidemic; we fail to find support.

  6. Intellectual disability, mental illness and offending behaviour: forensic cases from early twentieth-century Ireland.

    Science.gov (United States)

    Kelly, B D

    2010-09-01

    The history of institutional care for individuals with intellectual disability is under-researched, complex and troubling. To explore the experiences of women who may have had intellectual disability and/or mental illness and were admitted to forensic psychiatric care in early twentieth-century Ireland. All female case records at the Central Mental Hospital, Dublin from 1910 to 1948 (n = 42) were studied for evidence of possible intellectual disability and a series of five cases is presented in detail. These committals occurred in the context of adverse social conditions, over-crowding in asylums and a belief that rates of mental illness were rising. Particular challenges included diagnostic issues (especially in relation to intellectual disability), adjustment to asylum environments, mental illness and physical ill-health. The institutional experiences of individuals with intellectual disability represents an important area for further historical research, using larger and more varied forensic populations.

  7. Market Research and Socio-Political Consciousness in the Twentieth Century

    DEFF Research Database (Denmark)

    Schwarzkopf, Stefan

    2013-01-01

    Purpose – This paper investigates the case of the eminent British market researcher and social scientist Mark Alexander Abrams (1906 – 1994). Abrams’ career as a researcher spanned the six decades between the late 1920s and the late 1980s, and it bridged the gap between commercial market...... and consumer research on the one side and governmental social research on the other. By focusing on Abrams’ research strategies and career moves over these six decades, the paper establishes an alternative historical narrative to those that privilege the impact of capitalist market structures on the making...... of marketing as a professional field and academic discipline in the twentieth century. Design/methodology/approach – Based on archival research, the paper firstly establishes the biographical details of Abrams’ life and work. Secondly, the paper uses methodological and theoretical tools of historical sociology...

  8. Taming the unknown a history of algebra from antiquity to the early twentieth century

    CERN Document Server

    Katz, Victor J

    2014-01-01

    What is algebra? For some, it is an abstract language of x's and y's. For mathematics majors and professional mathematicians, it is a world of axiomatically defined constructs like groups, rings, and fields. Taming the Unknown considers how these two seemingly different types of algebra evolved and how they relate. Victor Katz and Karen Parshall explore the history of algebra, from its roots in the ancient civilizations of Egypt, Mesopotamia, Greece, China, and India, through its development in the medieval Islamic world and medieval and early modern Europe, to its modern form in the early twentieth century. Defining algebra originally as a collection of techniques for determining unknowns, the authors trace the development of these techniques from geometric beginnings in ancient Egypt and Mesopotamia and classical Greece. They show how similar problems were tackled in Alexandrian Greece, in China, and in India, then look at how medieval Islamic scholars shifted to an algorithmic stage, which was further dev...

  9. Body and Psychiatric Discourse in the Early Twentieth Century in Uruguay: Insufficiency, Weakness and Adaptation

    Directory of Open Access Journals (Sweden)

    Agustina Craviotto Corbellini

    2016-08-01

    Full Text Available This study analyzes the psychiatric medical discourse and experimental psychology during the twentieth century in Uruguay, as expert knowledge on children and as referents of the pedagogic discourse of that period. As an introduction some key elements of psychiatry in the country are presented; from them, it is stuyed how the dysfunction of the body became the focus of analysis that led to a series of school children´s classifications. The relationship of the dysfunctional body with school learning is at the core of the reflection, and indiscipline and mental weaknesses are taken as elements articulating the psychiatric and psychological discourses with the pedagogical one, through the notion of adjustment disorder.

  10. Natural histories of infectious disease: ecological vision in twentieth-century biomedical science.

    Science.gov (United States)

    Anderson, Warwick

    2004-01-01

    During the twentieth century, disease ecology emerged as a distinct disciplinary network within infectious diseases research. The key figures were Theobald Smith, F. Macfarlane Burnet, René Dubos, and Frank Fenner. They all drew on Darwinian evolutionism to fashion an integrative (but rarely holistic) understanding of disease processes, distinguishing themselves from reductionist "chemists" and mere "microbe hunters." They sought a more complex, biologically informed epidemiology. Their emphasis on competition and mutualism in the animated environment differed from the physical determinism that prevailed in much medical geography and environmental health research. Disease ecology derived in part from studies of the interaction of organisms - micro and macro - in tropical medicine, veterinary pathology, and immunology. It developed in postcolonial settler societies. Once a minority interest, disease ecology has attracted more attention since the 1980s for its explanations of disease emergence, antibiotic resistance, bioterrorism, and the health impacts of climate change.

  11. Medical confidentiality in the late nineteenth and early twentieth centuries: an Anglo-German comparison1

    Science.gov (United States)

    2012-01-01

    Summary Professional secrecy of doctors became an issue of considerable medico-legal and political debate in the late nineteenth and early twentieth centuries in both Germany and England, although the legal preconditions for this debate were quite different in the two countries. While in Germany medical confidentiality was a legal obligation and granted in court, no such statutory recognition of doctors’ professional secrecy existed in England. This paper is a comparative analysis of medical secrecy in three key areas - divorce trials, venereal disease and abortion - in both countries. Based on sources from the period between c.1870 and 1939, our paper shows how doctors tried to define the scope of professional secrecy as an integral part of their professional honour in relation to important matters of public health. PMID:21077462

  12. Physiology, propaganda, and pound animals: medical research and animal welfare in mid-twentieth century America.

    Science.gov (United States)

    Parascandola, John

    2007-07-01

    In 1952, the University of Michigan physiologist Robert Gesell shocked his colleagues at the business meeting of the American Physiological Society by reading a prepared statement in which he claimed that some of the animal experimentation being carried out by scientists was inhumane. He especially attacked the National Society for Medical Research (NSMR), an organization that had been founded to defend animal experimentation. This incident was part of a broader struggle taking place at the time between scientists and animal welfare advocates with respect to what restrictions, if any, should be placed on animal research. A particularly controversial issue was whether or not pound animals should be made available to laboratories for research. Two of the prominent players in this controversy were the NSMR and the Animal Welfare Institute, founded and run by Gesell's daughter, Christine Stevens. This article focuses on the interaction between these two organizations within the broader context of the debate over animal experimentation in the mid-twentieth century.

  13. [Puppet shows, Mexican television and health education in the mid-twentieth century].

    Science.gov (United States)

    Gudiño, María Rosa; Sosenski, Susana

    2016-10-10

    This article resurrects the puppet show Las calenturas de Don Ferruco (Don Ferruco's Fevers), which was televised in the late 1950s in order to help eradicate malaria in Mexico, as a useful instrument for health education. It analyzes how the spread of educational puppet shows on Mexican television showed the need to keep updating preventive healthcare pedagogy and it underlines the importance of television as an educational health-promotion production in the mid-twentieth century. The article discusses the early use of puppet shows as an especially important tool for what would later become mass-media transmission of discourses from the Secretaría de Salubridad y Asistencia (Department of Health and Healthcare).

  14. The Lost Worlds of Messmore & Damon: Science, Spectacle & Prehistoric Monsters in early-twentieth century America.

    Science.gov (United States)

    Manias, Chris

    2016-09-01

    In 1924, the model-making company Messmore & Damon, Inc. of New York unleashed their masterpiece: the Amphibious Dinosaurus Brontosaurus, a moving, breathing, roaring animatronic dinosaur, based on displays in the American Museum of Natural History. Over the 1920s and 1930s, this became the focus of an ever-increasing publicity campaign, as Messmore & Damon exhibited prehistoric automata in department stores, the media, and the Chicago World Fair of 1933-34. These displays were hugely popular and widely discussed, drawing from the increasing public appeal of paleontology. Mixing commercial entertainment with invocations of scientific value, Messmore & Damon's prehistoric creations offer a window into the meaning and popularity of the deep time sciences in early-twentieth century America, and the links between science and spectacle in this period. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. [Water pipelines conduits and urban sanitation in Cartagena in the beginning of the twentieth century].

    Science.gov (United States)

    Orrego, A L

    2000-01-01

    Throughout its history, Cartagena de Indias, a seaport in the Colombian Caribbean, has been handicapped for not offering salubrious conditions to its people and visitors. The lack of an aqueduct and a sewerage system was an impairment to progress. For nearly forty years (1890-1930) these problems have caused a myriad of medical discourses formulated by scientists, technicians and politicians. Cartagena's contribution to solve the sanitation problem in cities has consisted in making use of engineers' knowledge. The construction of urban facilities in the beginning of the twentieth century required a more technical knowledge, one which would advance a comprehensive solution to the water problem, ensure sufficient supply and efficient drainage. Thus, in the last turn of the century, the medical doctor is no longer the only authoritative voice when it comes to the management of urban life. The construction works which require an engineer, involving him in public health, have drawn a distinction between "hygiene" and "sanitary science".

  16. Women and political struggles: achievements and limitations lived in the second half of twentieth century

    Directory of Open Access Journals (Sweden)

    Flávia Fernandes de Carvalhaes

    2016-06-01

    Full Text Available The second half of the twentieth century was a period marked by important achievements and setbacks in the struggle for women's rights field. This study mapped out and described part of speeches, images and movements undertaken in that historical period and its effects on people's lives. Adopting a perspective of historical and theoretical analysis, the description looked up, first, the struggles carried out in some countries of Europe and the United States, highlighting its main challenges and difficulties. Then, the struggles undertaken are mapped in Brazil, with the analysis axis facing women inequality. Finally, it is considered that the political struggles carried out in the analyzed period had as greatest merits the disruption and exploitation of gender boundaries.

  17. Linguistic Capital and Its Transformation in the History of Russian in the Twentieth Century

    Directory of Open Access Journals (Sweden)

    Viktor Živov

    2013-02-01

    Full Text Available Standard language is conceptualized as linguistic capital, in terms of Pierre Bourdieu’s sociology. The Twentieth century in Russia was an epoch of revolutions; linguistic developments in revolutionary and post-revolutionary situations may be efficiently analyzed as transformations of linguistic capital: the old linguistic capital is discredited in the course of a cultural revolution and revolutionary linguistic usage becomes new linguistic capital. This process is characterized in Russia (from 1910 through to the 1920s and again in the 1980s and 1990s by the extensive use of borrowings, vulgar and jargon words, obscene expressions. The end of cultural revolutions is accompanied by the emergence of a new elite and by partial restoration of the old linguistic capital; it is appropriated by the new elite and adjusted to their demands. The article describes two cycles of these developments in the period from 1917 up to the present.

  18. An introduction to the poetics of sacred sound in twentieth-century music

    Directory of Open Access Journals (Sweden)

    Luigi Antonio Irlandini

    2013-12-01

    Full Text Available Along the twentieth century has occurred the beginning of a fusion between two very different horizons: Western musical composition and Hindu sonic theology. The essential content of this theology and the changes in Western musical language and aesthetics, society and culture which have allowed this fusion to take place are briefly outlined. Instrumental and vocal works by Karlheinz Stockhausen, Giacinto Scelsi, Michael Vetter and David Hykes provide specific examples and, in particular, raise the predicament between mysticism and rationalism, manifested in the dichotomy ècriture/inspiration. The study proceeds investigating the connections between music and meditation. In this context, overtone singing appears as a musical and meditative practice. The incorporation of this non-European or ancient vocal technique is evaluated as a dawning horizon in Western music. Overtone singing has required a practical emphasis through improvisation, suggesting a new musical praxis that does not separate composition from performance.

  19. Hidden in plain sight marketing prescription drugs to consumers in the twentieth century.

    Science.gov (United States)

    Greene, Jeremy A; Herzberg, David

    2010-05-01

    Although the public health impact of direct-to-consumer (DTC) pharmaceutical advertising remains a subject of great controversy, such promotion is typically understood as a recent phenomenon permitted only by changes in federal regulation of print and broadcast advertising over the past two decades. But today's omnipresent ads are only the most recent chapter in a longer history of DTC pharmaceutical promotion (including the ghostwriting of popular articles, organization of public-relations events, and implicit advertising of products to consumers) stretching back over the twentieth century. We use trade literature and archival materials to examine the continuity of efforts to promote prescription drugs to consumers and to better grapple with the public health significance of contemporary pharmaceutical marketing practices.

  20. Chinese Buddhist Nuns in the Twentieth Century: A Case Study in Wuhan

    Directory of Open Access Journals (Sweden)

    Yuan Yuan

    2015-02-01

    Full Text Available In this paper, through working at the intersection of the works on nationalism and women, and the literature on Buddhist nuns during the Republican period, I aim to take up questions of gender relations in the broader studies of Buddhism and Buddhist modernization. I explore the Buddhist nuns' movement by examining the establishment of various academies for female Buddhists. I also analyze the writings by female Buddhists in the twentieth century. In so doing, I argue that the Buddhist nuns' revival movement fitted into the broader women's liberation discourse and the national modernization project during this time. This paper promises to provide insights into the history of women and nationalism from a Buddhist perspective, and shed light on gender-related issues of modern Chinese Buddhism in the course of China's modernization.

  1. The Establishment of a Car-Based Leisure Regime in Twentieth Century Europe

    DEFF Research Database (Denmark)

    Cassamagnaghi, Silvia; Moretto, Giovanni; Wagner, Michael

    – despite collective Soviet politics – a “private” dream: a private property good for private use. It allowed, for the very first time, mobility (even if relative…) and freedom of travelling. Owning a car permitted to organize the leisure independently from the prearranged forms of leisure set by the State......Comparative analysis of tourism and of its development in three different countries – Denmark, Italy and Soviet Union – has revealed the importance of the car as the keystone for changes in the habits of leisure time consumption all over in Europe. Even considering the specific features (social......, economic and political) of each country, and the different decades in which this phenomenon has occurred, “individual” travel and stay has become, in Twentieth Century, the characteristics of dominance over other forms of organized and “collective” tourism. “Gentlemen, we do not make this tour to drive. We...

  2. Wave propagation in electromagnetic media

    CERN Document Server

    Davis, Julian L

    1990-01-01

    This is the second work of a set of two volumes on the phenomena of wave propagation in nonreacting and reacting media. The first, entitled Wave Propagation in Solids and Fluids (published by Springer-Verlag in 1988), deals with wave phenomena in nonreacting media (solids and fluids). This book is concerned with wave propagation in reacting media-specifically, in electro­ magnetic materials. Since these volumes were designed to be relatively self­ contained, we have taken the liberty of adapting some of the pertinent material, especially in the theory of hyperbolic partial differential equations (concerned with electromagnetic wave propagation), variational methods, and Hamilton-Jacobi theory, to the phenomena of electromagnetic waves. The purpose of this volume is similar to that of the first, except that here we are dealing with electromagnetic waves. We attempt to present a clear and systematic account of the mathematical methods of wave phenomena in electromagnetic materials that will be readily accessi...

  3. Reconstruction of nonlinear wave propagation

    Science.gov (United States)

    Fleischer, Jason W; Barsi, Christopher; Wan, Wenjie

    2013-04-23

    Disclosed are systems and methods for characterizing a nonlinear propagation environment by numerically propagating a measured output waveform resulting from a known input waveform. The numerical propagation reconstructs the input waveform, and in the process, the nonlinear environment is characterized. In certain embodiments, knowledge of the characterized nonlinear environment facilitates determination of an unknown input based on a measured output. Similarly, knowledge of the characterized nonlinear environment also facilitates formation of a desired output based on a configurable input. In both situations, the input thus characterized and the output thus obtained include features that would normally be lost in linear propagations. Such features can include evanescent waves and peripheral waves, such that an image thus obtained are inherently wide-angle, farfield form of microscopy.

  4. Propagation engineering in wireless communications

    CERN Document Server

    Ghasemi, Abdollah; Ghasemi, Farshid

    2016-01-01

    This book covers the basic principles for understanding radio wave propagation for common frequency bands used in radio-communications. This includes achievements and developments in propagation models for wireless communication. This book is intended to bridge the gap between the theoretical calculations and approaches to the applied procedures needed for radio links design in a proper manner. The authors emphasize propagation engineering by giving fundamental information and explain the use of basic principles together with technical achievements. This new edition includes additional information on radio wave propagation in guided media and technical issues for fiber optics cable networks with several examples and problems. This book also includes a solution manual - with 90 solved examples distributed throughout the chapters - and 158 problems including practical values and assumptions.

  5. Twentieth-century Victorian: Arthur Conan Doyle and the "Strand Magazine," 1891–1930, by Jonathan Cranfield [book review

    Directory of Open Access Journals (Sweden)

    Anne-Charlotte Mecklenburg

    2017-03-01

    Full Text Available Review of Jonathan Cranfield, Twentieth-century Victorian: Arthur Conan Doyle and the "Strand Magazine," 1891–1930. Edinburgh: Edinburgh University Press, 2016, hardcover, £75 (272p ISBN 978-1474406758; e-book, £75, ISBN 978-1474406772.

  6. Twentieth-century Victorian: Arthur Conan Doyle and the "Strand Magazine," 1891–1930, by Jonathan Cranfield [book review

    Directory of Open Access Journals (Sweden)

    Anne-Charlotte Mecklenburg

    2017-03-01

    Full Text Available Book review of Jonathan Cranfield, Twentieth-century Victorian: Arthur Conan Doyle and the "Strand Magazine," 1891–1930. Edinburgh: Edinburgh University Press, 2016, hardcover, £75 (272p ISBN 978-1474406758; e-book, £75, ISBN 978-1474406772.

  7. The Scientific Enlightenment System in Russia in the Early Twentieth Century as a Model for Popularizing Science

    Science.gov (United States)

    Balashova, Yuliya B.

    2016-01-01

    This research reconstructs the traditions of scientific enlightenment in Russia. The turn of the nineteenth and twentieth centuries was chosen as the most representative period. The modern age saw the establishment of the optimal model for advancing science in the global context and its crucial segment--Russian science. This period was…

  8. A New Teacher for a New Nation? Teacher Education, "English", and Schooling in Early Twentieth-Century Australia

    Science.gov (United States)

    Green, Bill; Reid, Jo-Anne

    2012-01-01

    The late nineteenth-century expansion of public schooling in Australia from an initial focus on the elementary phase to post-primary provision, and then to a more systematic secondary education over the early to mid-twentieth century, went hand in hand with the emergence of new populations of children and young people--a new constituency. In turn,…

  9. Twentieth-century global-mean sea-level rise: is the whole greater than the sum of the parts?

    NARCIS (Netherlands)

    Gregory, J.M.; White, N.J.; Church, J.A.; Bierkens, M.F.P.; Box, J.E.; Broeke, M.R. van den; Cogley, J.G.; Fettweis, X.; Hanna, E.; Huybrechts, P.; Konikow, L.F.; Leclercq, P.W.; Marzeion, B.; Oerlemans, J.; Tamisiea, E.; Wada, Y.

    2012-01-01

    Confidence in projections of global-mean sea level rise (GMSLR) depends on an ability to account for GMSLR during the twentieth century. There are contributions from ocean thermal expansion, mass loss from glaciers and ice sheets, groundwater extraction, and reservoir impoundment. Progress has been

  10. Public Expenditure on Education and Economic Growth in the USA in the Nineteenth and Twentieth Centuries in Comparative Perspective

    Science.gov (United States)

    Carpentier, Vincent

    2006-01-01

    Earlier studies of France, Germany and the UK suggest that a common framework exists to explain the relationship between public expenditure on education and economic growth in the nineteenth and twentieth centuries. This article shows that while a similar relationship exists in the USA, US policies were particularly committed to the educational…

  11. The creation of play spaces in twentieth-century Amsterdam: from an intervention of civil actors to a public policy

    NARCIS (Netherlands)

    Verstrate, L.; Karsten, L.

    2011-01-01

    This case study uncovers a turning point in the production of play space in Amsterdam. Whereas over the first half of the twentieth century the creation of play spaces used to be the primary responsibility of the Amsterdam civil society, this situation started to change after the Second World War. B

  12. YINSHUN'S RECOVERY OF SHIZHU PIPOSHA LUN A MADHYAMAKA-BASED PURE LAND PRACTICE IN TWENTIETH-CENTURY TAIWAN

    NARCIS (Netherlands)

    Travagnin, Stefania

    2013-01-01

    Yinshun (1906-2005) is regarded as one of the eminent monks of twentieth-century Chinese Buddhism. In the mission of reinventing Chinese Buddhism Yinshun engaged particularly in the revival and restatement of Madhyamaka. His interpretation of Ngrjuna's texts, the reassessment of the links between pr

  13. Those Who Served: Report of the Twentieth Century Fund Task Force on Policies Toward Veterans. Background Paper.

    Science.gov (United States)

    Taussig, Michael K.

    Veterans' policies and programs are examined by a task force of the Twentieth Century Fund. Part 1, the report of the task force, includes sections on the rationale for veterans benefits, recommendations for further benefits and programs, and a dissenting opinion by one task force member. Recommendations are summarized into five basic areas: (1)…

  14. The Yankees of Europe? A New View on Technology and Productivity in German Manufacturing in the Early Twentieth Century

    NARCIS (Netherlands)

    Timmer, Marcel P.; Veenstra, Joost; Woltjer, P.J.

    2016-01-01

    Labor productivity in German manufacturing lagged behind the United States in the early twentieth century. Traditionally, this is attributed to dichotomous technology paths across the Atlantic. However, various industry case studies suggest rapid diffusion of U.S. technologies in Germany. We develop

  15. Educational Ideas in Geography Education in Sweden during the Nineteenth and Early Twentieth Centuries: The Relationship between Maps and Texts

    Science.gov (United States)

    Hennerdal, Pontus

    2015-01-01

    Descriptions of the geography education of the nineteenth and early twentieth centuries in Sweden are typically offered to contrast with current ideas in geography education, and the content of geography textbooks is the focus of this comparison. The role of maps and visual pedagogy are ignored, and the educational ideas developed from regional…

  16. "El destierro de los Chinos": Popular Perspectives on Chinese-Mexican Intermarriage in the Early Twentieth Century

    Science.gov (United States)

    Romero, Robert Chao

    2007-01-01

    This essay examines Chinese-Mexican interracial marriage during the early twentieth century through the lens of Mexican popular culture. Comedy, poetry, cartoons, and musical recordings of the time portrayed these marriages as relationships of abuse, slavery, and neglect, and rejected the offspring of such unions as subhuman and unworthy of full…

  17. Educational Ideas in Geography Education in Sweden during the Nineteenth and Early Twentieth Centuries: The Relationship between Maps and Texts

    Science.gov (United States)

    Hennerdal, Pontus

    2015-01-01

    Descriptions of the geography education of the nineteenth and early twentieth centuries in Sweden are typically offered to contrast with current ideas in geography education, and the content of geography textbooks is the focus of this comparison. The role of maps and visual pedagogy are ignored, and the educational ideas developed from regional…

  18. Cumulative Index to the Sixteenth through the Twentieth Semiannual Reports of the Commission to the Congress. January 1954 - June 1956

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Lewis L.

    1956-07-30

    The sixteenth through the twentieth semiannual reports of the United States Atomic Energy Commission to Congress are covered in this cumulative index, which included both a name and subject index as aids to finding information in the full reports.. The full semiannual reports themselves cover the major unclassified activities of the Commission from January 1954 through June 1956.

  19. "Strong Mothers Make Strong Children": Sports, Eugenics and Nationalism in Brazil at the Beginning of the Twentieth Century

    Science.gov (United States)

    Goellner, Silvana Vilodre; Votre, Sebastiao Josue; Pinheiro, Maria Claudia Brandao

    2012-01-01

    Based on post-structural feminist and gender studies, the present article analyses the importance given to the practice of physical education, sports and exercise as part of the national policy to strengthen the Caucasian-Brazilian population at the beginning of the twentieth century, emphasising the priority made of the White female body as the…

  20. The Yankees of Europe? A New View on Technology and Productivity in German Manufacturing in the Early Twentieth Century

    NARCIS (Netherlands)

    Timmer, Marcel P.; Veenstra, Joost; Woltjer, Pieter J.

    Labor productivity in German manufacturing lagged persistently behind the United States in the early twentieth century. Traditionally, this is attributed to dichotomous technology paths across the Atlantic. However, various industry case studies suggest rapid diffusion of U.S. technologies in

  1. Chemistry and Chemical Education through Text and Image: Analysis of Twentieth Century Textbooks Used in Brazilian Context

    Science.gov (United States)

    Souza, Karina Ap F. D.; Porto, Paulo Alves

    2012-01-01

    Assuming that textbooks give literary expression to cultural and ideological values of a nation or group, we propose the analysis of chemistry textbooks used in Brazilian universities throughout the twentieth century. We analyzed iconographic and textual aspects of 31 textbooks which had significant diffusion in the context of Brazilian…

  2. The Democratic School and the Pedagogy of Janusz Korczak: A Model of Early Twentieth Century Reform in Modern Israel

    Science.gov (United States)

    Engel, Liba H.

    2013-01-01

    This article explores the history and pedagogy of Janusz Korczak within the context of his contemporary early Twentieth-Century European Innovative Educators which include Maria Montessori, Homer Lane, A.S. Neill, and Anton Semyonovitch Makarenko. The pedagogies of the aforementioned are compared and contrasted within the literature.

  3. Working women in France, nineteenth and twentieth centuries. Where, when, and which women were in work at marriage?

    NARCIS (Netherlands)

    Zijdeman, Richard L.; van Leeuwen, Marco H D; Rébaudo, Danièle; Pélissier, Jean Pierre

    2014-01-01

    We look at women's labour force participation for the whole of France in the nineteenth and twentieth centuries. We study to what extent young women were working at the time of their marriage, in which occupations, and how differences in labour force participation might be explained. Using a sample

  4. Internal atmospheric noise characteristics in twentieth century coupled atmosphere-ocean model simulations

    Science.gov (United States)

    Colfescu, Ioana; Schneider, Edwin K.

    2017-09-01

    The statistical characteristics of the atmospheric internal variability (hereafter internal atmospheric noise) for surface pressure (PS) in twentieth century simulations of a coupled general circulation model are documented. The atmospheric noise is determined from daily post-industrial (1871-1998) Community Climate System Model 3 simulations by removing the SST and externally forced responses from the total fields. The forced responses are found from atmosphere-only simulations forced by the SST and external forcing of the coupled runs. However, we do not address the influence of the SST variability on the synoptic scale high frequency weather noise.The spatial patterns of the main seasonal modes of atmospheric noise variability are found for boreal winter and summer from empirical orthogonal function analyses performed globally and for various regions, including the North Atlantic, the North Pacific, and the equatorial Pacific. The temporal characteristics of the modes are illustrated by power spectra and probability density functions (PDF) of the principal components (PC). Our findings show that, for two different realizations of noise, the variability is dominated by large scale spatial structures of the atmospheric noise that resemble observed patterns, and that their relative amplitudes in the CGCM and AGCM simulations are very similar. The regional expression of the dominant global mode, a seasonally dependent AO-like or AAO-like pattern is also found in the regional analyses, with similar time dependence. The PCs in the CGCM and the corresponding SST forced AGCM simulations are uncorrelated, but the spectra and PDFs of the CGCM and AGCM PCs are similar.The temporal structures of the noise PCs are white at timescales larger than few months, so that these modes can be thought of as stochastic forcings (in time) for the climate system. The PDFs of the noise PCs are not statistically distinguishable from Gaussian distributions with the same standard deviation

  5. Three twentieth-century multiauthored neurological handbooks--a historical analysis and bibliometric comparison.

    Science.gov (United States)

    Koehler, Peter J; Stahnisch, Frank W

    2014-01-01

    The emergence of neurology as a separate specialty from internal medicine and psychiatry took several decades, starting at the end of the nineteenth century. This can be adequately reconstructed by focusing on the establishment of specialized journals, societies, university chairs, the invention and application of specific instruments, medical practices, and certainly also the publication of pivotal textbooks in the field. Particularly around 1900, the German-speaking countries played an integral role in this process. In this article, one aspect is extensively explored, notably the publication (in the twentieth century) of three comprehensive and influential multivolume and multiauthor handbooks entirely devoted to neurology. All available volumes of Max Lewandowsky's Handbuch der Neurologie (1910-1914) and the Handbuch der Neurologie (1935-1937) of Oswald Bumke and Otfrid Foerster were analyzed. The handbooks were then compared with Pierre Vinken's and George Bruyn's Handbook of Clinical Neurology (1968-2002). Over the span of nearly a century these publications became ever more comprehensive and developed into a global, encompassing project as is reflected in the increasing number of foreign authors. Whereas the first two handbooks were published mainly in German, "Vinken & Bruyn" was eventually published entirely in English, indicating the general changes in the scientific language of neurology after World War II. Distinctions include the uniformity of the series, manner of editorial involvement, thematic comprehensiveness, inclusion of volume editors in "Vinken & Bruyn," and the provision of index volumes. The increasing use of authorities in various neurological subspecialties is an important factor by which these handbooks contrast with many compact neurological textbooks that were available at the time. For historiographical purposes, the three neurological handbooks considered here were important sources for the general study of the history of medicine and

  6. Three Twentieth-Century Multiauthored Neurological Handbooks – A Historical Analysis and Bibliometric Comparison

    Science.gov (United States)

    Koehler, Peter J.; Stahnisch, Frank W.

    2013-01-01

    The emergence of neurology as a separate specialty from internal medicine and psychiatry took several decades, starting at the end of the nineteenth century. This can be adequately reconstructed by focusing on the establishment of specialized journals, societies, university chairs, the invention and application of specific instruments, medical practices, and certainly also the publication of pivotal textbooks in the field. Particularly around 1900, the German-speaking countries played an integral role in this process. In this article, one aspect is extensively explored, notably the publication (in the twentieth century) of three comprehensive and influential multivolume and multiauthor handbooks entirely devoted to neurology. All available volumes of Max Lewandowsky's Handbuch der Neurologie (1910–1914) and the Handbuch der Neurologie (1935–1937) of Oswald Bumke and Otfrid Foerster were analyzed. The handbooks were then compared with Pierre Vinken's and George Bruyn's Handbook of Clinical Neurology (1968–2002). Over the span of nearly a century these publications became ever more comprehensive and developed into a global, encompassing project as is reflected in the increasing number of foreign authors. Whereas the first two handbooks were published mainly in German, “Vinken & Bruyn” was eventually published entirely in English, indicating the general changes in the scientific language of neurology after World War II. Distinctions include the uniformity of the series, manner of editorial involvement, thematic comprehensiveness, inclusion of volume editors in “Vinken & Bruyn,” and the provision of index volumes. The increasing use of authorities in various neurological subspecialties is an important factor by which these handbooks contrast with many compact neurological textbooks that were available at the time. For historiographical purposes, the three neurological handbooks considered here were important sources for the general study of the history of

  7. Building Baluchitherium and Indricotherium: imperial and international networks in early-twentieth century paleontology.

    Science.gov (United States)

    Manias, Chris

    2015-01-01

    Over the first decades of the twentieth century, the fragmentary remains of a huge prehistoric ungulate were unearthed in scientific expeditions in India, Turkestan and Mongolia. Following channels of formal and informal empire, these were transported to collections in Britain, Russia and the United States. While striking and of immense size, the bones proved extremely difficult to interpret. Alternately naming the creature Paraceratherium, Baluchitherium and Indricotherium, paleontologists Clive Forster-Cooper, Alexei Borissiak and Henry Fairfield Osborn struggled over the reconstruction of this gigantic fossil mammal. However, despite these problems, shared work on the creature served as a focus for collaboration and exchange rather than rivalry between these three scientific communities. Not only did the initial interpretation and analysis depend on pre-existing connections between British and American paleontological institutions, but the need for comparative material, recognition and contacts brought British and American scholars into communication and exchange with their counterparts in the Soviet Union. This article examines these processes. It first uses these excavations as a comparative case-study of different manifestations of colonial science in this period, examining how scholars in the Britain, the Russian Empire and the United States used formal and informal colonial links to Asia to pursue new research. It then moves to examine how the common problem of reconstructing this giant animal drew metropolitan scientific communities together, at least for a time. The construction of the Baluchitherium and Indricotherium illustrates the drives to expand research both imperially and internationally in the early-twentieth century, but also the continual problems in resources, institutionalization, transport and communication that could run up against scientific work.

  8. Climate change in Hungary during the twentieth century according to Feddema

    Science.gov (United States)

    Breuer, Hajnalka; Ács, Ferenc; Skarbit, Nóra

    2017-02-01

    Climate change in Hungary during the twentieth century is analyzed using Feddema's original scheme suitable for global scale applications (F-GS) and Feddema's fine-tuned scheme designed for Hungarian applications (F-HU). Input data of precipitation (P) and air temperature (T) are taken from the Climatic Research Unit (CRU) TS 1.2 database constructing P-T data referring to three 30-year periods (1901-1930, 1941-1970, 1971-2000) and two 50-year periods (1901-1950, 1951-2000). The method and data organizational effects are compared using these schemes and data sets. The results show that the evaluation of the climate change process depends much more on the methodological rather than on data organizational effects. Methodical fine-tuning effects considerably improved the spatial distribution, while the organization of data improved the insight into the dynamic of the processes. According to F-GS, there is no climate change on 76.7 % of Hungarian territory. According to F-HU, such areas amount to only 38.5 %. The main climate change process for F-GS is drying, while for F-HU drying and warming beside either drying or warming. For both models, the most climate change affected areas are characterized by higher altitudes, such as in the Mecsek and Villány Mountains (geographical region Transdanubia), in the Bükk Mountains (geographical region North Hungarian Mountains), and in the region of the so-called Danube Bend. The spatially most realistic climate description is obtained by using F-HU and the 30-year data sets. It is to be noted that Köppen's, Holdridge's, and Thornthwaite's methods are less suitable than F-HU for representing the process of climate change in Hungary in the twentieth century.

  9. Heritage and Observatories in Brazil at the Turn of the Twentieth Century: an Overview

    Science.gov (United States)

    Granato, Marcus

    The first systematic asronomical observations in the southern hemisphere were in Pernambuco, northeastern Brazil, in the short period of Dutch rule in the region (1637-1644). Later, in the late nineteenth and early twentieth centuries, there were three observatories on Brazilian soil: Imperial Observatório do Rio de Janeiro, Observatório da Escola Politecnica, both in Rio de Janeiro and Observatório Central, in the southern city of Porto Alegre. The first was created by Imperial decree by D. Pedro I, on 15 October 1827, while the second, linked to Universidade do Brasil, was established on 5 July 1881. The third was planned in 1889, but only inaugurated on 24 January 1908 as part of the Escola de Engenharia. All three institutions exist to this day, and their scientific instruments of historical value are included in cultural heritage preservation projects. The largest collection of this kind of objects is at Museu de Astronomia e Ciéncias Afins (MAST), most of whose 2000 artefacts come from the Imperial Observatory (today the National Observatory). Many of them were produced in Germany by manufacturers such as Gustav Heyde, Carl Zeiss, Askania-Werke, Carl Bamberg and Max Kohl. The buildings of the Observatório Central (1921) and Observatório Nacional (1921) are listed by federal and state heritage protection agencies, particularly because they were purpose built for astronomical research and have architectural features typical of the late nineteenth and early twentieth centuries that have not been altered over the years.

  10. Twentieth century warming of the tropical Atlantic captured by Sr-U paleothermometry

    Science.gov (United States)

    Alpert, Alice E.; Cohen, Anne L.; Oppo, Delia W.; DeCarlo, Thomas M.; Gaetani, Glenn A.; Hernandez-Delgado, Edwin A.; Winter, Amos; Gonneea, Meagan

    2017-01-01

    Coral skeletons are valuable archives of past ocean conditions. However, interpretation of coral paleotemperature records is confounded by uncertainties associated with single-element ratio thermometers, including Sr/Ca. A new approach, Sr-U, uses U/Ca to constrain the influence of Rayleigh fractionation on Sr/Ca. Here we build on the initial Pacific Porites Sr-U calibration to include multiple Atlantic and Pacific coral genera from multiple coral reef locations spanning a temperature range of 23.15–30.12°C. Accounting for the wintertime growth cessation of one Bermuda coral, we show that Sr-U is strongly correlated with the average water temperature at each location (r2 = 0.91, P period 1900–1996 is within 0.12°C of the average instrumental temperature at this site and captures the twentieth century warming trend of 0.06°C per decade. Sr-U also captures the timing of multiyear variability but with higher amplitude than implied by the instrumental data. Mean Sr-U temperatures and patterns of multiyear variability were replicated in a second coral in the same grid box. Conversely, Sr/Ca records from the same two corals were inconsistent with each other and failed to capture absolute sea temperatures, timing of multiyear variability, or the twentieth century warming trend. Our results suggest that coral Sr-U paleothermometry is a promising new tool for reconstruction of past ocean temperatures.

  11. Comparative study of white porcelain from the common use of nineteenth and twentieth centuries with PXRF

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Wislley Dueli da; Appoloni, Carlos Roberto [Universidade Estadual de Londrina (UEL), PR (Brazil)

    2011-07-01

    Full text: The technique of X-ray fluorescence (XRF) is widely used for qualitative and quantitative researches on the chemical composition of various types of samples, such as archaeological, art and cultural heritage materials or samples. The great advantage of this technique is that it allows a nondestructive and simultaneous multielement analysis. It has a low cost and portable system device that can be used in situ. The study of archaeological artifacts and cultural heritage by means of analytical techniques with hand held devices becomes increasingly routine today. Several types of portable energy dispersive X-ray fluorescence (EDXRF) have been used in many different situations involving in situ analysis covering a wide range of geometries, detectors, voltage and current applied in the X-ray tubes. This study aims to identify and compare the main elements that make up samples of ceramic pottery for common use by the late nineteenth and early and late twentieth century, as a way of using the methodology of analysis by EDXRF equipment PXRF - LFNA - 02. Being able to identify that the key element present in the glaze of ceramics from the early twentieth century was the Pb, it was possible to classify the samples as faience cream ware and not pearlware as it was guided by conventional archaeological analysis, where the rating was based only on color enamel porcelain. Elements such as K, Ca, Cr, Mn, Fe, Co, Zn, Rb, Sr, Zr are also found in different concentrations depending on the clay used in the manufacture of earthenware, maker of the period and that it was produced. From analysis of the type EDXRF is possible to compare different manufacturing techniques, both in enamel and in ceramic slurry and often even the color of his pieces. (author)

  12. Social Skills: Adolf Meyer's Revision of Clinical Skill for the New Psychiatry of the Twentieth Century.

    Science.gov (United States)

    Lamb, Susan

    2015-07-01

    Adolf Meyer (1866-1950) exercised considerable influence over the development of Anglo-American psychiatry during the first half of the twentieth century. The concepts and techniques he implemented at his prominent Phipps Psychiatric Clinic at Johns Hopkins remain important to psychiatric practice and neuro-scientific research today. In the 1890s, Meyer revised scientific medicine's traditional notion of clinical skill to serve what he called the 'New Psychiatry', a clinical discipline that embodied social and scientific ideals shared with other 'new' progressive reform movements in the United States. This revision conformed to his concept of psychobiology - his biological theory of mind and mental disorders - and accorded with his definition of scientific medicine as a unity of clinical-pathological methods and therapeutics. Combining insights from evolutionary biology, neuron theory and American pragmatist philosophy, Meyer concluded that subjective experience and social behaviour were functions of human biology. In addition to the time-honoured techniques devised to exploit the material data of the diseased body - observing and recording in the clinic, dissecting in the morgue and conducting histological experiments in the laboratory - he insisted that psychiatrists must also be skilled at wielding social interaction and interpersonal relationships as investigative and therapeutic tools in order to conceptualise, collect, analyse and apply the ephemeral data of 'social adaptation'. An examination of his clinical practices and teaching at Johns Hopkins between 1913 and 1917 shows how particular historical and intellectual contexts shaped Meyer's conceptualisation of social behaviour as a biological function and, subsequently, his new vision of clinical skill for twentieth-century psychiatry.

  13. Ultra High Energy Nuclei Propagation

    CERN Document Server

    Aloisio, Roberto

    2008-01-01

    We discuss the problem of ultra high energy nuclei propagation in astrophysical backgrounds. We present a new analytical computation scheme based on the hypothesis of continuos energy losses in a kinetic formulation of the particles propagation. This scheme enables the computation of the fluxes of ultra high energy nuclei as well as the fluxes of secondaries (nuclei and nucleons) produced by the process of photo-disintegration suffered by nuclei.

  14. Propagation in Diagonal Anisotropic Chirowaveguides

    Directory of Open Access Journals (Sweden)

    S. Aib

    2017-01-01

    Full Text Available A theoretical study of electromagnetic wave propagation in parallel plate chirowaveguide is presented. The waveguide is filled with a chiral material having diagonal anisotropic constitutive parameters. The propagation characterization in this medium is based on algebraic formulation of Maxwell’s equations combined with the constitutive relations. Three propagation regions are identified: the fast-fast-wave region, the fast-slow-wave region, and the slow-slow-wave region. This paper focuses completely on the propagation in the first region, where the dispersion modal equations are obtained and solved. The cut-off frequencies calculation leads to three cases of the plane wave propagation in anisotropic chiral medium. The particularity of these results is the possibility of controlling the appropriate cut-off frequencies by choosing the adequate physical parameters values. The specificity of this study lies in the bifurcation modes confirmation and the possible contribution to the design of optical devices such as high-pass filters, as well as positive and negative propagation constants. This negative constant is an important feature of metamaterials which shows the phenomena of backward waves. Original results of the biaxial anisotropic chiral metamaterial are obtained and discussed.

  15. NASA System Engineering Design Process

    Science.gov (United States)

    Roman, Jose

    2011-01-01

    This slide presentation reviews NASA's use of systems engineering for the complete life cycle of a project. Systems engineering is a methodical, disciplined approach for the design, realization, technical management, operations, and retirement of a system. Each phase of a NASA project is terminated with a Key decision point (KDP), which is supported by major reviews.

  16. NASA information resources management handbook

    Science.gov (United States)

    1992-01-01

    This National Aeronautics and Space Administration (NASA) Handbook (NHB) implements recent changes to Federal laws and regulations involving the acquisition, management, and use of Federal Information Processing (FIP) resources. This document defines NASA's Information Resources Management (IRM) practices and procedures and is applicable to all NASA personnel. The dynamic nature of the IRM environment requires that the controlling management practices and procedures for an Agency at the leading edge of technology, such as NASA, must be periodically updated to reflect the changes in this environment. This revision has been undertaken to accommodate changes in the technology and the impact of new laws and regulations dealing with IRM. The contents of this document will be subject to a complete review annually to determine its continued applicability to the acquisition, management, and use of FIP resources by NASA. Updates to this document will be accomplished by page changes. This revision cancels NHB 2410.1D, dated April 1985.

  17. The physical theory and propagation model of THz atmospheric propagation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, R; Yao, J Q; Xu, D G; Wang, J L; Wang, P, E-mail: wangran19861014@163.com [College of Precision Instrument and Opto-electronics Engineering, Institute of Laser and Opto-electronics, Tianjin University, Tianjin 300072 (China)

    2011-02-01

    Terahertz (THz) radiation is extensively applied in diverse fields, such as space communication, Earth environment observation, atmosphere science, remote sensing and so on. And the research on propagation features of THz wave in the atmosphere becomes more and more important. This paper firstly illuminates the advantages and outlook of THz in space technology. Then it introduces the theoretical framework of THz atmospheric propagation, including some fundamental physical concepts and processes. The attenuation effect (especially the absorption of water vapor), the scattering of aerosol particles and the effect of turbulent flow mainly influence THz atmosphere propagation. Fundamental physical laws are illuminated as well, such as Lamber-beer law, Mie scattering theory and radiative transfer equation. The last part comprises the demonstration and comparison of THz atmosphere propagation models like Moliere(V5), SARTre and AMATERASU. The essential problems are the deep analysis of physical mechanism of this process, the construction of atmospheric propagation model and databases of every kind of material in the atmosphere, and the standardization of measurement procedures.

  18. The physical theory and propagation model of THz atmospheric propagation

    Science.gov (United States)

    Wang, R.; Yao, J. Q.; Xu, D. G.; Wang, J. L.; Wang, P.

    2011-02-01

    Terahertz (THz) radiation is extensively applied in diverse fields, such as space communication, Earth environment observation, atmosphere science, remote sensing and so on. And the research on propagation features of THz wave in the atmosphere becomes more and more important. This paper firstly illuminates the advantages and outlook of THz in space technology. Then it introduces the theoretical framework of THz atmospheric propagation, including some fundamental physical concepts and processes. The attenuation effect (especially the absorption of water vapor), the scattering of aerosol particles and the effect of turbulent flow mainly influence THz atmosphere propagation. Fundamental physical laws are illuminated as well, such as Lamber-beer law, Mie scattering theory and radiative transfer equation. The last part comprises the demonstration and comparison of THz atmosphere propagation models like Moliere(V5), SARTre and AMATERASU. The essential problems are the deep analysis of physical mechanism of this process, the construction of atmospheric propagation model and databases of every kind of material in the atmosphere, and the standardization of measurement procedures.

  19. NASA Work Experience

    Science.gov (United States)

    Frandsen, Athela F.

    2015-01-01

    I have had the opportunity to support the analytical laboratories in chemical analysis of unknown samples, using Optical Microscopy (OM), Polarizing Light Microscopy (PLM), Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEMEDS), and X-ray Powder Diffraction (XPD). I have assisted in characterizing fibers pulled from a spacecraft, a white fibrous residue discovered in a jet refueler truck, brown residue from a plant habitat slated for delivery to the ISS (International Space Station), corrosion on a pipe from a sprinkler, and air filtration material brought back from the ISS. I also conducted my own fiber study in order to practice techniques and further my understanding of background concepts. Furthermore, I had the opportunity to participate in diverse work assignments, where I was assigned to work with other branches of the engineering department for 1-2 days each. The first was in the Materials Science branch where I participated in the construction of the plant habitat intended for use in research aboard the ISS. The second was in the Testing Design branch where I assisted with tensile and hardness testing of over 40 samples. In addition, I have had the privilege to attend multiple tours of the NASA KSC campus, including to the Astronaut Crew Quarters, the VAB (the main area, the Columbia room, and the catwalk), the Visitor Center housing the shuttle Atlantis, the Saturn-V exhibit, the Prototype laboratory, SWAMP WORKS, the Shuttle Landing Facility, the Crawler, and the Booster Fabrication Facility (BFF). Lastly, much of my coursework prepared me for this experience, including numerous laboratory courses with topics diverse as chemistry, physics, and biology.

  20. NASA Robotic Neurosurgery Testbed

    Science.gov (United States)

    Mah, Robert

    1997-01-01

    The detection of tissue interface (e.g., normal tissue, cancer, tumor) has been limited clinically to tactile feedback, temperature monitoring, and the use of a miniature ultrasound probe for tissue differentiation during surgical operations, In neurosurgery, the needle used in the standard stereotactic CT or MRI guided brain biopsy provides no information about the tissue being sampled. The tissue sampled depends entirely upon the accuracy with which the localization provided by the preoperative CT or MRI scan is translated to the intracranial biopsy site. In addition, no information about the tissue being traversed by the needle (e.g., a blood vessel) is provided. Hemorrhage due to the biopsy needle tearing a blood vessel within the brain is the most devastating complication of stereotactic CT/MRI guided brain biopsy. A robotic neurosurgery testbed has been developed at NASA Ames Research Center as a spin-off of technologies from space, aeronautics and medical programs. The invention entitled "Robotic Neurosurgery Leading to Multimodality Devices for Tissue Identification" is nearing a state ready for commercialization. The devices will: 1) improve diagnostic accuracy and precision of general surgery, with near term emphasis on stereotactic brain biopsy, 2) automate tissue identification, with near term emphasis on stereotactic brain biopsy, to permit remote control of the procedure, and 3) reduce morbidity for stereotactic brain biopsy. The commercial impact from this work is the potential development of a whole new generation of smart surgical tools to increase the safety, accuracy and efficiency of surgical procedures. Other potential markets include smart surgical tools for tumor ablation in neurosurgery, general exploratory surgery, prostate cancer surgery, and breast cancer surgery.

  1. NASA Robotic Neurosurgery Testbed

    Science.gov (United States)

    Mah, Robert

    1997-01-01

    The detection of tissue interface (e.g., normal tissue, cancer, tumor) has been limited clinically to tactile feedback, temperature monitoring, and the use of a miniature ultrasound probe for tissue differentiation during surgical operations, In neurosurgery, the needle used in the standard stereotactic CT or MRI guided brain biopsy provides no information about the tissue being sampled. The tissue sampled depends entirely upon the accuracy with which the localization provided by the preoperative CT or MRI scan is translated to the intracranial biopsy site. In addition, no information about the tissue being traversed by the needle (e.g., a blood vessel) is provided. Hemorrhage due to the biopsy needle tearing a blood vessel within the brain is the most devastating complication of stereotactic CT/MRI guided brain biopsy. A robotic neurosurgery testbed has been developed at NASA Ames Research Center as a spin-off of technologies from space, aeronautics and medical programs. The invention entitled "Robotic Neurosurgery Leading to Multimodality Devices for Tissue Identification" is nearing a state ready for commercialization. The devices will: 1) improve diagnostic accuracy and precision of general surgery, with near term emphasis on stereotactic brain biopsy, 2) automate tissue identification, with near term emphasis on stereotactic brain biopsy, to permit remote control of the procedure, and 3) reduce morbidity for stereotactic brain biopsy. The commercial impact from this work is the potential development of a whole new generation of smart surgical tools to increase the safety, accuracy and efficiency of surgical procedures. Other potential markets include smart surgical tools for tumor ablation in neurosurgery, general exploratory surgery, prostate cancer surgery, and breast cancer surgery.

  2. NASA's Approach to Software Assurance

    Science.gov (United States)

    Wetherholt, Martha

    2015-01-01

    NASA defines software assurance as: the planned and systematic set of activities that ensure conformance of software life cycle processes and products to requirements, standards, and procedures via quality, safety, reliability, and independent verification and validation. NASA's implementation of this approach to the quality, safety, reliability, security and verification and validation of software is brought together in one discipline, software assurance. Organizationally, NASA has software assurance at each NASA center, a Software Assurance Manager at NASA Headquarters, a Software Assurance Technical Fellow (currently the same person as the SA Manager), and an Independent Verification and Validation Organization with its own facility. An umbrella risk mitigation strategy for safety and mission success assurance of NASA's software, software assurance covers a wide area and is better structured to address the dynamic changes in how software is developed, used, and managed, as well as it's increasingly complex functionality. Being flexible, risk based, and prepared for challenges in software at NASA is essential, especially as much of our software is unique for each mission.

  3. Update on NASA Microelectronics Activities

    Science.gov (United States)

    Label, Kenneth A.; Sampson, Michael J.; Casey, Megan; Lauenstein, Jean-Marie

    2017-01-01

    Mission Statement: The NASA Electronic Parts and Packaging (NEPP) Program provides NASA's leadership for developing and maintaining guidance for the screening, qualification, test. and usage of EEE parts by NASA as well as in collaboration with other government Agencies and industry. NASA Space Technology Mission Directorate (STMD) "STMD rapidly develops, demonstrates, and infuses revolutionary, high-payoff technologies through transparent, collaborative partnerships, expanding the boundaries of the aerospace enterprise." Mission Statement: The Space Environments Testing Management Office (SETMO) will identify, prioritize, and manage a select suite of Agency key capabilities/assets that are deemed to be essential to the future needs of NASA or the nation, including some capabilities that lack an adequate business base over the budget horizon. NESC mission is to perform value-added independent testing, analysis, and assessments of NASA's high-risk projects to ensure safety and mission success. NASA Space Environments and Avionics Fellows as well as Radiation and EEE Parts Community of Practice (CoP) leads.

  4. Parametrization of Fully Dressed Quark Propagator

    Institute of Scientific and Technical Information of China (English)

    MA Wei-Xing; ZHU Ji-Zhen; ZHOU Li-Juan; SHEN Peng-Nian; HU Zhao-Hui

    2005-01-01

    Based on an extensive study of the Dyson-Schwinger equations for a fully dressed quark propagator in the "rainbow" approximation, a parametrized form of the quark propagator is suggested. The corresponding quark selfform of the quark propagator proposed in this work describes a confining quark propagation, and is quite convenient to be used in any numerical calculations.

  5. Survey of propagation Model in wireless Network

    Directory of Open Access Journals (Sweden)

    Hemant Kumar Sharma

    2011-05-01

    Full Text Available To implementation of mobile ad hoc network wave propagation models are necessary to determine propagation characteristic through a medium. Wireless mobile ad hoc networks are self creating and self organizing entity. Propagation study provides an estimation of signal characteristics. Accurate prediction of radio propagation behaviour for MANET is becoming a difficult task. This paper presents investigation of propagation model. Radio wave propagation mechanisms are absorption, reflection, refraction, diffraction and scattering. This paper discuss free space model, two rays model, and cost 231 hata and its variants and fading model, and summarized the advantages and disadvantages of these model. This study would be helpful in choosing the correct propagation model.

  6. The FLIC Overlap Quark Propagator

    CERN Document Server

    Kamleh, W; Leinweber, D B; Williams, A G; Zhang, J; Kamleh, Waseem; Bowman, Patrick O.; Leinweber, Derek B.; Williams, Anthony G.; Zhang, Jianbo

    2004-01-01

    FLIC overlap fermions are a variant of the standard (Wilson) overlap action, with the FLIC (Fat Link Irrelevant Clover) action as the overlap kernel rather than the Wilson action. The structure of the FLIC overlap fermion propagator in momentum space is studied, and a comparison against previous studies of the Wilson overlap propagator in quenched QCD is performed. To explore the scaling properties of the propagator for the two actions, numerical calculations are performed in Landau Gauge across three lattices with different lattice spacing $a$ and similar physical volumes. We find that at light quark masses the acti ons agree in both the infrared and the ultraviolet, but at heavier masses some disagreement in the ultraviolet appears. This is attributed to the two action s having different discretisation errors with the FLIC overlap providing superior performance in this regime. Both actions scale reasonably, but some scaling violations are observed.

  7. Wave propagation in ballistic gelatine.

    Science.gov (United States)

    Naarayan, Srinivasan S; Subhash, Ghatu

    2017-01-23

    Wave propagation characteristics in long cylindrical specimens of ballistic gelatine have been investigated using a high speed digital camera and hyper elastic constitutive models. The induced transient deformation is modelled with strain rate dependent Mooney-Rivlin parameters which are determined by modelling the stress-strain response of gelatine at a range of strain rates. The varying velocity of wave propagation through the gelatine cylinder is derived as a function of prestress or stretch in the gelatine specimen. A finite element analysis is conducted using the above constitutive model by suitably defining the impulse imparted by the polymer bar into the gelatine specimen. The model results are found to capture the experimentally observed wave propagation characteristics in gelatine effectively.

  8. Propagating Class and Method Combination

    DEFF Research Database (Denmark)

    Ernst, Erik

    1999-01-01

    This paper presents a mixin based class and method combination mechanism with block structure propagation. Traditionally, mixins can be composed to form new classes, possibly merging the implementations of methods (as in CLOS). In our approach, a class or method combination operation may cause any...... number of implicit combinations. For example, it is possible to specify separate aspects of a family of classes, and then combine several aspects into a full-fledged class family. The combination expressions would explicitly combine whole-family aspects, and by propagation implicitly combine the aspects...... for each member of the class family, and again by propagation implicitly compose each method from its aspects. As opposed to CLOS, this is type-checked statically; and as opposed to other systems for advanced class combination/ merging/weaving, it is integrated directly in the language, ensuring a clear...

  9. Gluon propagator with dynamical quarks

    CERN Document Server

    Papavassiliou, Joannis

    2014-01-01

    We review recent work on the effects of quark loops on the gluon propagator in the Landau gauge, relying mainly on the Schwinger-Dyson equations that describe the two-point sector of QCD. Particularly important in this context is the detailed study of how the standard gluon mass generation mechanism, which is responsible for the infrared finiteness of the quenched gluon propagator, is affected by the inclusions of dynamical quarks. This issue is especially relevant and timely, given the qualitative picture that emerges from recent unquenched lattice simulations. Our results demonstrate clearly that the gluon mass generation persists, and that the corresponding saturation points of the unquenched gluon propagators are progressively suppressed, as the number of quark flavors increases.

  10. Wave equations for pulse propagation

    Energy Technology Data Exchange (ETDEWEB)

    Shore, B.W.

    1987-06-24

    Theoretical discussions of the propagation of pulses of laser radiation through atomic or molecular vapor rely on a number of traditional approximations for idealizing the radiation and the molecules, and for quantifying their mutual interaction by various equations of propagation (for the radiation) and excitation (for the molecules). In treating short-pulse phenomena it is essential to consider coherent excitation phenomena of the sort that is manifest in Rabi oscillations of atomic or molecular populations. Such processes are not adequately treated by rate equations for excitation nor by rate equations for radiation. As part of a more comprehensive treatment of the coupled equations that describe propagation of short pulses, this memo presents background discussion of the equations that describe the field. This memo discusses the origin, in Maxwell's equations, of the wave equation used in the description of pulse propagation. It notes the separation into lamellar and solenoidal (or longitudinal and transverse) and positive and negative frequency parts. It mentions the possibility of separating the polarization field into linear and nonlinear parts, in order to define a susceptibility or index of refraction and, from these, a phase and group velocity. The memo discusses various ways of characterizing the polarization characteristics of plane waves, that is, of parameterizing a transverse unit vector, such as the Jones vector, the Stokes vector, and the Poincare sphere. It discusses the connection between macroscopically defined quantities, such as the intensity or, more generally, the Stokes parameters, and microscopic field amplitudes. The material presented here is a portion of a more extensive treatment of propagation to be presented separately. The equations presented here have been described in various books and articles. They are collected here as a summary and review of theory needed when treating pulse propagation.

  11. An Overview of NASA Biotechnology

    Science.gov (United States)

    Pusey, Marc L.

    1997-01-01

    Biotechnology research at NASA has comprised three separate areas; cell science and tissue culture, separations methods, and macromolecular crystal growth. This presentation will primarily focus on the macromolecular crystal growth.

  12. NASA_Airborne_Lidar_Flights

    Data.gov (United States)

    National Aeronautics and Space Administration — Data from the 1982 NASA Langley Airborne Lidar flights following the eruption of El Chichon beginning in July 1982 and continuing to January 1984. Data in ASCII...

  13. NASA ASTER Level 1T

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is an advanced multispectral imager that was launched on board NASA's Terra spacecraft in...

  14. NASA 3D Models: Aquarius

    Data.gov (United States)

    National Aeronautics and Space Administration — Aquarius is making NASA's first space-based global observations of ocean surface salinity, flying 657 kilometers (408 miles) above Earth in a sun-synchronous polar...

  15. NASA's approach to space commercialization

    Science.gov (United States)

    Gillam, Isaac T., IV

    1986-01-01

    The NASA Office of Commercial Programs fosters private participation in commercially oriented space projects. Five Centers for the Commercial Development of Space encourage new ideas and perform research which may yield commercial processes and products for space ventures. Joint agreements allow companies who present ideas to NASA and provide flight hardware access to a free launch and return from orbit. The experimenters furnish NASA with sufficient data to demonstrate the significance of the results. Ground-based tests are arranged for smaller companies to test the feasibility of concepts before committing to the costs of developing hardware. Joint studies of mutual interest are performed by NASA and private sector researchers, and two companies have signed agreements for a series of flights in which launch costs are stretched out to meet projected income. Although Shuttle flights went on hold following the Challenger disaster, extensive work continues on the preparation of commercial research payloads that will fly when Shuttle flights resume.

  16. NASA's computer science research program

    Science.gov (United States)

    Larsen, R. L.

    1983-01-01

    Following a major assessment of NASA's computing technology needs, a new program of computer science research has been initiated by the Agency. The program includes work in concurrent processing, management of large scale scientific databases, software engineering, reliable computing, and artificial intelligence. The program is driven by applications requirements in computational fluid dynamics, image processing, sensor data management, real-time mission control and autonomous systems. It consists of university research, in-house NASA research, and NASA's Research Institute for Advanced Computer Science (RIACS) and Institute for Computer Applications in Science and Engineering (ICASE). The overall goal is to provide the technical foundation within NASA to exploit advancing computing technology in aerospace applications.

  17. NASA Technical Reports Server (NTRS)

    Data.gov (United States)

    National Aeronautics and Space Administration — The NTRS is a valuable resource for researchers, students, educators, and the public to access NASA's current and historical technical literature and engineering...

  18. NASA 3D Models: Aqua

    Data.gov (United States)

    National Aeronautics and Space Administration — Aqua, Latin for water, is a NASA Earth Science satellite mission named for the large amount of information that the mission is collecting about the Earth's water...

  19. NASA 3D Models: Cassini

    Data.gov (United States)

    National Aeronautics and Space Administration — Cassini spacecraft from SPACE rendering package, built by Michael Oberle under NASA contract at JPL. Includes orbiter only, Huygens probe detached. Accurate except...

  20. NASA 3D Models: Terra

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA launched the Earth Observing System's flagship satellite Terra, named for Earth, on December 18, 1999. Terra has been collecting data about Earth's changing...

  1. NASA 3D Models: TRMM

    Data.gov (United States)

    National Aeronautics and Space Administration — The Tropical Rainfall Measuring Mission (TRMM) is a joint mission between NASA and the Japan Aerospace Exploration Agency (JAXA) designed to monitor and study...

  2. NASA 3D Models: SORCE

    Data.gov (United States)

    National Aeronautics and Space Administration — The Solar Radiation and Climate Experiment (SORCE) is a NASA-sponsored satellite mission that is providing state-of-the-art measurements of incoming x-ray,...

  3. BOOK REVIEW: Quantum Generations. A history of physics in the twentieth century

    Science.gov (United States)

    Brown, Neil

    2000-03-01

    Physics has a long history, but more physics has been discovered in the twentieth century than in all previous eras together. That in itself would be a sufficient justification for a history of physics in the twentieth century, but the end of the previous century also marked a discontinuity, from Newtonian classical physics to relativity and quantum mechanics. If any single event marks the start of the process it is the discovery of x-rays in 1895, and Kragh's century spans from about 1895 to about 1995. It is, of course, too much for a single volume, even a large one, and Kragh recognizes from the outset that he has to be selective and concentrate on those subjects that define twentieth-century physics. For the early part of the century the author relies on carefully chosen secondary sources, to avoid the near-impossible task of absorbing a multitude of original papers. The recent period is more difficult, and the sources are articles, reviews, and the recollections of physicists. The book is in three main sections, roughly to the end of World War I, to the end of World War II, and up to 1995, plus a retrospective summary. It deals with more than just discoveries in physics, looking also at physicists and institutions, and at their interactions with the rest of society. The broad outlines of many discoveries are often known to physicists who have no special interest in history, and Kragh is careful to point out where these conventional accounts are inadequate. The first chapters set the scene at the end of the nineteenth century, acknowledging that there was a belief that all the grand underlying principles had been established, but also pointing out that there was a ferment of attempts to reinterpret physics in terms of concepts like vortices and hyperspaces. The history begins with the mould-breaking discoveries of x-rays, radioactivity and the electron. The chapters that follow look at theories about atomic structure, and at quantum physics, relativity and

  4. Vegetative propagation of Bambusa vulgaris

    Directory of Open Access Journals (Sweden)

    Rafael Malfitano Braga

    2017-06-01

    Full Text Available Bamboo is an important source of raw material of multiple uses. The development of simple techniques for its propagation is a practical way to enable its implementation in ownership of low technology. The present work had the objective of evaluating artisanal propagation methods for Bambusa vulgaris. Two types of propagules were tested, with buds budded or not, and three relative positions to the removal of vegetative material on the culm. The best propagule was with only one node, extracted from the lower thirds of the stem, presenting 72% of rooting. This result demonstrates its potential for seedling production of this species under low tech.

  5. SIS epidemic propagation on hypergraphs

    CERN Document Server

    Bodó, Ágnes; Simon, Péter L

    2015-01-01

    Mathematical modeling of epidemic propagation on networks is extended to hypergraphs in order to account for both the community structure and the nonlinear dependence of the infection pressure on the number of infected neighbours. The exact master equations of the propagation process are derived for an arbitrary hypergraph given by its incidence matrix. Based on these, moment closure approximation and mean-?eld models are introduced and compared to individual-based stochastic simulations. The simulation algorithm, developed for networks, is extended to hypergraphs. The e?ects of hypergraph structure and the model parameters are investigated via individual-based simulation results.

  6. Industrial and Systems Engineering Applications in NASA

    Science.gov (United States)

    Shivers, Charles H.

    2006-01-01

    A viewgraph presentation on the many applications of Industrial and Systems Engineering used for safe NASA missions is shown. The topics include: 1) NASA Information; 2) Industrial Engineering; 3) Systems Engineering; and 4) Major NASA Programs.

  7. NASA's Plan for SDLS Testing

    Science.gov (United States)

    Bailey, Brandon

    2015-01-01

    The Space Data Link Security (SDLS) Protocol is a Consultative Committee for Space Data Systems (CCSDS) standard which extends the known Data Link protocols to secure data being sent over a space link by providing confidentiality and integrity services. This plan outlines the approach by National Aeronautics Space Administration (NASA) in performing testing of the SDLS protocol using a prototype based on an existing NASA missions simulator.

  8. NASA Day at the Capitol

    Science.gov (United States)

    2009-01-01

    Astronaut Rex Walheim (center) speaks to members of the Mississippi House of Representatives in chambers during NASA Day at the Capitol in Jackson on Feb. 19. Walheim was joined at the podium by members of the Mississippi House of Representatives Gulf Coast delegation, as well as Stennis Space Center Director Gene Goldman (astronaut's immediate right) and NASA's Shared Services Center Director Rick Arbuthnot and Partners for Stennis Executive Director Tish Williams (astronaut's immediate left).

  9. NASA's telemedicine testbeds: Commercial benefit

    Science.gov (United States)

    Doarn, Charles R.; Whitten, Raymond

    1998-01-01

    The National Aeronautics and Space Administration (NASA) has been developing and applying telemedicine to support space flight since the Agency's beginning. Telemetry of physiological parameters from spacecraft to ground controllers is critical to assess the health status of humans in extreme and remote environments. Requisite systems to support medical care and maintain readiness will evolve as mission duration and complexity increase. Developing appropriate protocols and procedures to support multinational, multicultural missions is a key objective of this activity. NASA has created an Agency-wide strategic plan that focuses on the development and integration of technology into the health care delivery systems for space flight to meet these challenges. In order to evaluate technology and systems that can enhance inflight medical care and medical education, NASA has established and conducted several testbeds. Additionally, in June of 1997, NASA established a Commercial Space Center (CSC) for Medical Informatics and Technology Applications at Yale University School of Medicine. These testbeds and the CSC foster the leveraging of technology and resources between government, academia and industry to enhance health care. This commercial endeavor will influence both the delivery of health care in space and on the ground. To date, NASA's activities in telemedicine have provided new ideas in the application of telecommunications and information systems to health care. NASA's Spacebridge to Russia, an Internet-based telemedicine testbed, is one example of how telemedicine and medical education can be conducted using the Internet and its associated tools. Other NASA activities, including the development of a portable telemedicine workstation, which has been demonstrated on the Crow Indian Reservation and in the Texas Prison System, show promise in serving as significant adjuncts to the delivery of health care. As NASA continues to meet the challenges of space flight, the

  10. [Pain and anesthesiology : aspects of the development of modern pain therapy in the twentieth century].

    Science.gov (United States)

    Witte, W

    2011-06-01

    The connection between the development of anesthesiology and pain therapy in the twentieth century is close. The optimistic idea to overcome pain by using general anesthesia derives from the nineteenth century. Treatment of nonsurgical pain remained in the background for a long time and innovations in pain medicine did not improve the insufficient care for patients with postoperative pain. Therapy of chronic pain was mainly surgical and the extreme of this surgical approach was psychosurgery. In the years following World War II leucotomy and lobotomy were established as methods to separate the psychological processing of pain from the experience of pain. Meanwhile, the French "pain surgeon" René Leriche elaborated a theory of pain where chronic pain was no longer seen as a symptom but as a "douleur-maladie", a pain disease. His theory was considered on various occasions but did not gain acceptance before the 1950s. Research in anesthesiology, such as that conducted by the American scientist Henry Beecher separated psyche and physiology with respect to pathological pain. This was contrasted by the approach of clinical anesthesia to pain therapy, which was based on regional anesthesia. The first "pain clinics" were "nerve block clinics". John Bonica, a regional anesthesiologist, extended the framework of pain therapy by introducing multidisciplinary teamwork into the therapy of chronic pain. From today's viewpoint his 1953 monograph The Management of Chronic Pain is a milestone in the development of modern pain therapy. However, Bonica's work did not attain major importance until 1960 when he was appointed to a newly established chair. Gradually, chronic pain was recognized as an independent illness and differentiated as such from acute pain. In 1965 the gate control theory by Melzack and Wall offered a possible explanation for the mechanisms of chronic pain. By the end of the 1970s the spectrum was extended to the biopsychosocial approach which was foremost

  11. Twentieth-century astronomical heritage: the case of the Brazilian National Observatory

    Science.gov (United States)

    Barboza, Christina Helena

    2015-08-01

    The National Observatory of Brazil was created in 1827. It was initially focused on the practical teaching of Astronomy to the students of military and naval academies. Since the mid-nineteenth century to the early twentieth century it was installed over the ruins of a Jesuit church located in the center of Rio de Janeiro, capital of the Brazilian Empire.Due to the constant complaints of its successive directors, the search for a new site to house the Observatory began in 1911. The new headquarters of the institution were located on the hill of São Januário, a little further but still around the city center of Rio de Janeiro. Its inauguration took place in 1921.The main building of the new Observatory was based on one of the Brazilian pavilions of the Turin Exhibition of 1911, and its architecture can be characterized as eclectic. The pavilions intended to house the many telescopes were scattered in a large wooded area. Since 1985 all these facilities are protected by the Federal government, as a consequence of the same initiative that gave birth to the Museum of Astronomy and Related Sciences, which has the custody also of the Observatory’s former instruments, furniture, and documents.Although built in the early twentieth century the National Observatory new facilities reveal astronomical practices typical of the previous century. One of its most important activities was the determination of the legal time, a task that justifies its location in the urban environment. It was also responsible for the organization of expeditions destined to determine the geographical positions of railroads and the borders of Brazil. For this reason, the Museum of Astronomy has currently more than 3,000 portable instruments. Moreover, these instruments belong to the domain of Astronomy, but also to Geodesy, Meteorology, Electricity. Due to the creation of the Museum of Astronomy, this rich collection is now open to public visitation, and has become the object of scholarly

  12. My Internship at NASA

    Science.gov (United States)

    Lopez, Isaac

    2016-01-01

    My name is Isaac Lopez and I am a junior at the University of Houston majoring in Mechanical Engineering Technology. I will be completing my first tour at the NASA-Johnson Space Center ("JSC") as a Mechanical Engineer within the Human Interfaces Branch. Throughout my tour, I was given the opportunity to work on multiple projects that have expanded my knowledge and interest in acoustics and engineering design. One of the projects I worked on at JSC consisted of doing acoustic simulation of the EVA comm. cap. While working on the comm. cap headset, my main duty consisted of simulating the acoustics of the headset to find a solution to the condensing water that can accumulate and block the acoustic tube, causing attenuation or complete loss of audio in one ear for an astronaut using the EVA. For this project, I had to create a Creo model of the comm. cap so that I would be able to import it into Comsol for acoustic simulation. I also had the opportunity to design a portable and lightweight beam degrader for the EEE Parts and Radiation team. With the help of Creo, I was able to make a CAD design and put together a small working prototype for the radiation team to demonstrate the capabilities that the beam degrader had. In addition to these projects, JSC allowed me to work closely on projects with other interns. I had the opportunity to help another intern with his acoustic diverter, intended to improve the sound quality in Node 1 of the ISS. During this project, I helped with some of the acoustic testing inside the anechoic chamber as well as helping record data during testing at the ISS mock up. During the course of my first tour, I was able to learn and continually improve on my CAD drafting skills. With each project I worked on, I acquired new ways to create and improve various designs with various constraints. Furthermore, I also had the opportunity to work with electrical engineers and learn about the electronic components that would provide control of the beam

  13. The NASA Technical Report Server

    Science.gov (United States)

    Nelson, Michael L.; Gottlich, Gretchen L.; Bianco, David J.; Paulson, Sharon S.; Binkley, Robert L.; Kellogg, Yvonne D.; Beaumont, Chris J.; Schmunk, Robert B.; Kurtz, Michael J.; Accomazzi, Alberto

    1995-01-01

    The National Aeronautics and Space Act of 1958 established NASA and charged it to "provide for the widest practicable and appropriate dissemination of information concerning its activities and the results thereof." The search for innovative methods to distribute NASA's information lead a grass-roots team to create the NASA Technical Report Server (NTRS), which uses the World Wide Web and other popular Internet-based information systems as search engines. The NTRS is an inter-center effort which provides uniform access to various distributed publication servers residing on the Internet. Users have immediate desktop access to technical publications from NASA centers and institutes. The NTRS is comprised of several units, some constructed especially for inclusion in NTRS, and others that are existing NASA publication services that NTRS reuses. This paper presents the NTRS architecture, usage metrics, and the lessons learned while implementing and maintaining the service. The NTRS is largely constructed with freely available software running on existing hardware. NTRS builds upon existing hardware and software, and the resulting additional exposure for the body of literature contained ensures that NASA's institutional knowledge base will continue to receive the widest practicable and appropriate dissemination.

  14. NASA Software Engineering Benchmarking Study

    Science.gov (United States)

    Rarick, Heather L.; Godfrey, Sara H.; Kelly, John C.; Crumbley, Robert T.; Wifl, Joel M.

    2013-01-01

    To identify best practices for the improvement of software engineering on projects, NASA's Offices of Chief Engineer (OCE) and Safety and Mission Assurance (OSMA) formed a team led by Heather Rarick and Sally Godfrey to conduct this benchmarking study. The primary goals of the study are to identify best practices that: Improve the management and technical development of software intensive systems; Have a track record of successful deployment by aerospace industries, universities [including research and development (R&D) laboratories], and defense services, as well as NASA's own component Centers; and Identify candidate solutions for NASA's software issues. Beginning in the late fall of 2010, focus topics were chosen and interview questions were developed, based on the NASA top software challenges. Between February 2011 and November 2011, the Benchmark Team interviewed a total of 18 organizations, consisting of five NASA Centers, five industry organizations, four defense services organizations, and four university or university R and D laboratory organizations. A software assurance representative also participated in each of the interviews to focus on assurance and software safety best practices. Interviewees provided a wealth of information on each topic area that included: software policy, software acquisition, software assurance, testing, training, maintaining rigor in small projects, metrics, and use of the Capability Maturity Model Integration (CMMI) framework, as well as a number of special topics that came up in the discussions. NASA's software engineering practices compared favorably with the external organizations in most benchmark areas, but in every topic, there were ways in which NASA could improve its practices. Compared to defense services organizations and some of the industry organizations, one of NASA's notable weaknesses involved communication with contractors regarding its policies and requirements for acquired software. One of NASA's strengths

  15. The universal condition: medical constructions of 'congenital phimosis' in twentieth century New Zealand and their implications for child rearing.

    Science.gov (United States)

    Watson, Lindsay R

    2014-01-01

    'Congenital phimosis' was one of a number of pseudo-pathologies that entered mainstream medicine in the nineteenth century. In the twentieth century Truby King, Henry Jellett, and Eric Corkill advocated premature foreskin retraction as the first intervention to manage 'congenital phimosis'. If that failed they recommended circumcision, although eventually it became more expedient to use circumcision exclusively. The nineteenth-century justification for such interventions was to prevent masturbation, but by the middle of the twentieth century this was replaced by prevention of infections. Gairdner's landmark paper of 1949 turned New Zealand doctors away from 'congenital phimosis' and non-therapeutic circumcision, although some doctors and persisting family traditions maintained both interventions until the end of the century.

  16. Historical occurrence and extinction of Atlantic salmon in the River Elbe from the fourteenth to the twentieth centuries

    Directory of Open Access Journals (Sweden)

    Andreska J.

    2015-03-01

    Full Text Available Data on the occurrence, biology, and historical background of the Atlantic salmon, Salmo salar L., (Pisces, Salmoniformes in the Elbe river basin (Europe, North Sea drainage area with a focus on Bohemian territory (Central Europe from the fourteenth to twentieth centuries are summarized in this paper. Historical methods of salmon fishing in Central Europe and historical legal protection of salmon in Bohemia are presented. The salmon is a model example of species which was extirpated as a result of anthropogenic changes in the landscape and rivers in some water systems. The human activities, such as stream bed regulation, dam system construction, other migration barriers, water pollution, fisheries exploitation, that led to the extirpation of Atlantic salmon in the Elbe river basin (are discussed. The last sporadic migrating native salmon were registered in the Bohemian section of the Elbe river basin in the mid twentieth century.

  17. Conference Report: Environmental Protection in the Global Twentieth Century: International Organizations, Networks and Diffusion of Ideas and Policies

    DEFF Research Database (Denmark)

    Meyer, Jan-Henrik

    Environmental Protection in the Global Twentieth Century: International Organizations, Networks and Diffusion of Ideas and Policies KFG International Conference held on 25-27 October 2012 The long rays of the yellow autumn sun shining on the red leaves of the Free University Berlin's Dahlem Campus...... provided a local touch of nature for an international conference devoted to the protection of the environment on a global scale. Sixteen researchers from eleven different countries from Europe and overseas gathered from 25 to 27 October 2012 at the Free University's Silberlaube conference centre to discuss...... "Environmental Protection in the Global Twentieth Century: International Organizations, Networks and Diffusion of Ideas and Policies". The conference was hosted and sponsored by the Research College "The Transformative Power of Europe" (jointly directed by TANJA BÖRZEL and THOMAS RISSE) at Free University's Otto...

  18. Conference Report: Environmental Protection in the Global Twentieth Century: International Organizations, Networks and Diffusion of Ideas and Policies

    DEFF Research Database (Denmark)

    Meyer, Jan-Henrik

    Environmental Protection in the Global Twentieth Century: International Organizations, Networks and Diffusion of Ideas and Policies KFG International Conference held on 25-27 October 2012 The long rays of the yellow autumn sun shining on the red leaves of the Free University Berlin's Dahlem Campus...... provided a local touch of nature for an international conference devoted to the protection of the environment on a global scale. Sixteen researchers from eleven different countries from Europe and overseas gathered from 25 to 27 October 2012 at the Free University's Silberlaube conference centre to discuss...... "Environmental Protection in the Global Twentieth Century: International Organizations, Networks and Diffusion of Ideas and Policies". The conference was hosted and sponsored by the Research College "The Transformative Power of Europe" (jointly directed by TANJA BÖRZEL and THOMAS RISSE) at Free University's Otto...

  19. Long-Term Trends in Space-Ground Atmospheric Propagation Measurements

    Science.gov (United States)

    Zemba, Michael J.; Nessel, James A.; Morse, Jacquelynne R.

    2015-01-01

    Propagation measurement campaigns are critical to characterizing the atmospheric behavior of a location and efficiently designing space-ground links. However, as global climate change affects weather patterns, the long-term trends of propagation data may be impacted over periods of decades or longer. Particularly, at high microwave frequencies (10 GHz and above), rain plays a dominant role in the attenuation statistics, and it has been observed that rain events over the past 50 years have trended toward increased frequency, intensity, and rain height. In the interest of quantifying the impact of these phenomena on long-term trends in propagation data, this paper compares two 20 GHz measurement campaigns both conducted at NASAs White Sands facility in New Mexico. The first is from the Advanced Communications Technology Satellite (ACTS) propagation campaign from 1994 to 1998, while the second is amplitude data recorded during a site test interferometer (STI) phase characterization campaign from 2009 to 2014.

  20. Sound propagation through nonuniform ducts

    Science.gov (United States)

    Nayfeh, A. H.

    1976-01-01

    Methods of determining the transmission and attenuation of sound propagating in nonuniform ducts with and without mean flows are discussed. The approaches reviewed include purely numerical techniques, quasi-one-dimensional approximations, solutions for slowly varying cross sections, solutions for weak wall undulations, approximation of the duct by a series of stepped uniform cross sections, variational methods and solutions for the mode envelopes.

  1. Radio frequency propagation made easy

    CERN Document Server

    Faruque, Saleh

    2015-01-01

    This book introduces Radio Frequency Propagation to a broad audience.  The author blends theory and practice to bring readers up-to-date in key concepts, underlying principles and practical applications of wireless communications.  The presentation is designed to be easily accessible, minimizing mathematics and maximizing visuals.

  2. Invisibility cloaking without superluminal propagation

    Energy Technology Data Exchange (ETDEWEB)

    Perczel, Janos; Leonhardt, Ulf [School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16 9SS (United Kingdom); Tyc, Tomas, E-mail: jp394@st-andrews.ac.uk, E-mail: tomtyc@physics.muni.cz, E-mail: ulf@st-andrews.ac.uk [Faculty of Science, Kotlarska 2 and Faculty of Informatics, Botanicka 68a, Masaryk University, 61137 Brno (Czech Republic)

    2011-08-15

    Conventional cloaking based on Euclidean transformation optics requires that the speed of light should tend to infinity on the inner surface of the cloak. Non-Euclidean cloaking still needs media with superluminal propagation. Here we show by giving an example that this is no longer necessary.

  3. Wave equations for pulse propagation

    Science.gov (United States)

    Shore, B. W.

    1987-06-01

    Theoretical discussions of the propagation of pulses of laser radiation through atomic or molecular vapor rely on a number of traditional approximations for idealizing the radiation and the molecules, and for quantifying their mutual interaction by various equations of propagation (for the radiation) and excitation (for the molecules). In treating short-pulse phenomena it is essential to consider coherent excitation phenomena of the sort that is manifest in Rabi oscillations of atomic or molecular populations. Such processes are not adequately treated by rate equations for excitation nor by rate equations for radiation. As part of a more comprehensive treatment of the coupled equations that describe propagation of short pulses, this memo presents background discussion of the equations that describe the field. This memo discusses the origin, in Maxwell's equations, of the wave equation used in the description of pulse propagation. It notes the separation into lamellar and solenoidal (or longitudinal and transverse) and positive and negative frequency parts. It mentions the possibility of separating the polarization field into linear and nonlinear parts, in order to define a susceptibility or index of refraction and, from these, a phase and group velocity.

  4. Expectation Propagation for Exponential Families

    OpenAIRE

    Seeger, Matthias

    2005-01-01

    This is a tutorial describing the Expectation Propagation (EP) algorithm for a general exponential family. Our focus is on simplicity of exposition. Although the overhead of translating a specific model into its exponential family representation can be considerable, many apparent complications of EP can simply be sidestepped by working in this canonical representation.

  5. Overseas propagation of kiwifruit pollinator

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ One year after granting to the Italian firm Kiwigold Consortium the world-wide propagation and commercialization rights of Jintao,a female cultivar plant from the novel variety of kiwifruit (Actinidia chinensis Planch), the CAS Wuhan Botanical Garden (WBG) reached a new agreement with the firm on the similar right of a male plant cultivar Moshan-4.

  6. Propagators in Polymer Quantum Mechanics

    CERN Document Server

    Flores-González, Ernesto; Reyes, Juan D

    2013-01-01

    Polymer Quantum Mechanics is based on some of the techniques used in the loop quantization of gravity that are adapted to describe systems possessing a finite number of degrees of freedom. It has been used in two ways: on one hand it has been used to represent some aspects of the loop quantization in a simpler context, and, on the other, it has been applied to each of the infinite mechanical modes of other systems. Indeed, this polymer approach was recently implemented for the free scalar field propagator. In this work we compute the polymer propagators of the free particle and a particle in a box; amusingly, just as in the non polymeric case, the one of the particle in a box may be computed also from that of the free particle using the method of images. We verify the propagators hereby obtained satisfy standard properties such as: consistency with initial conditions, composition and Green's function character. Furthermore they are also shown to reduce to the usual Schr\\"odinger propagators in the limit of sm...

  7. Light Front Fermion Model Propagation

    Institute of Scientific and Technical Information of China (English)

    Jorge Henrique Sales; Alfredo Takashi Suzuki

    2013-01-01

    In this work we consider the propagation of two fermion fields interacting with each other by the exchange of intermediate scalar bosons in the light front.We obtain the corrections up to fourth order in the coupling constant using hierarchical equations in order to obtain the bound state equation (Bethe-Salpeter equation).

  8. Self-Averaging Expectation Propagation

    DEFF Research Database (Denmark)

    Cakmak, Burak; Opper, Manfred; Fleury, Bernard Henri

    We investigate the problem of approximate inference using Expectation Propagation (EP) for large systems under some statistical assumptions. Our approach tries to overcome the numerical bottleneck of EP caused by the inversion of large matrices. Assuming that the measurement matrices are realizat...... on a signal recovery problem of compressed sensing and compare with standard EP....

  9. Ultraviolet asymptotics of glueball propagators

    CERN Document Server

    Bochicchio, M

    2013-01-01

    We point out that perturbation theory in conjunction with the renormalization group (RG) puts a severe constraint on the structure of the large-N non-perturbative glueball propagators in SU(N) pure YM, in QCD and in n=1 SUSY QCD with massless quarks, or in any confining asymptotically-free gauge theory massless in perturbation theory. For the scalar and pseudoscalar glueball propagators in pure YM and QCD with massless quarks we check in detail the RG-improved estimate to the order of the leading and next-to-leading logarithms by means of a remarkable three-loop computation by Chetyrkin et al. We investigate as to whether the aforementioned constraint is satisfied by any of the scalar or pseudoscalar glueball propagators computed in the framework of the AdS String/ large-N Gauge Theory correspondence and of a recent proposal based on a Topological Field Theory underlying the large-N limit of YM. We find that none of the proposals for the scalar or the pseudoscalar glueball propagators based on the AdS String/...

  10. [Physical restraint of patients: historical notes relating to the nineteenth and twentieth century].

    Science.gov (United States)

    Fariña-López, Emilio; Estévez-Guerra, Gabriel J

    2011-03-01

    Physical restraint has been historically considered a necessary procedure to control the behaviour of the mentally ill. In the late eighteenth century moral treatment would pave the way for new initiatives against restraint, such as those instituted by British psychiatrists. They stressed the importance of training and supervision, as well as a minimum staff ratio, as being determining factors in reducing the use of restraint. This philosophy of treatment, despite its benefits, was introduced later and to a lesser extent in the rest of Europe, although, in other countries care was also made more humane through new therapeutic procedures. By contrast, in the United States most psychiatrists disagreed with those who advocated non-restraint, and continued using controversial methods to control the behaviour of patients. In Spain many difficulties hindered the improvement of conditions in institutions, many of which were in a sorry state. The initiatives of a few professionals and some cautious legal advances tried to alleviate the harshness of the treatment methods used. In the early twentieth century professional manuals were already available, which included the care to be given during the application of physical restraints. However it was not until the 1950, when the emergence of new psychotropic drugs and the distribution of important guidelines on the protection of the rights of patients that the widespread use of this procedure would be successfully reduced.

  11. Creeping, drinking, dying: the cinematic portal and the microscopic world of the twentieth-century cell.

    Science.gov (United States)

    Landecker, Hannah

    2011-09-01

    Film scholars have long posed the question of the specificity of the film medium and the apparatus of cinema, asking what is unique to cinema, how it constrains and enables filmmakers and audiences in particular ways that other media do not. This question has rarely been considered in relation to scientific film, and here it is posed within the specific context of cell biology: What does the use oftime-based media such as film coupled with the microscope allow scientists to experience that other visualization practices do not? Examining three episodes in the twentieth-century study of the cell, this article argues that the apparatus ofmicrocinematography constitutes what might be thought of as a technical portal to another world, a door that determines the experience of the world that lies on the other side of it. In this case, the design of apparatuses to capture time-lapsed images enabled the acceleration of cellular time, bringing it into the realm of human perception and experience. Further, the experience of the cellular temporal world was part of a distinct kind of cell biology, one that was focused on behavior rather than structure, focused on the relation between cells, and between the cell and its milieu rather than on cell-intrinsic features such as chromosomes or organelles. As such, the instruments and technical design of the microcinematographic apparatus may be understood as a kind of materialized epistemology, the history of which can elucidate how cinema was and is used to produce scientific knowledge.

  12. Using the Twentieth Century Reanalysis to assess climate variability for the European wind industry

    CERN Document Server

    Bett, Philip E; Clark, Robin T

    2014-01-01

    We characterise the long-term variability of European near-surface wind speeds using 140 years of data from the Twentieth Century Reanalysis (20CR), and consider the potential of such long-baseline climate data sets for wind energy applications. The low resolution of the 20CR would severely restrict its use on its own for wind farm site-screening. We therefore perform a simple statistical calibration to link it to the higher-resolution ERA-Interim data set (ERAI), such that the adjusted 20CR data has the same wind speed distribution at each location as ERAI during their common period. Using this corrected 20CR data set, wind speeds and variability are characterised in terms of the long-term mean, standard deviation, and corresponding trends. Many regions of interest show extremely weak trends on century timescales, but contain large multidecadal variability. Variations in the form of the wind speed distribution are assessed in terms of its deciles; we find that the commonly-used Weibull distribution often pro...

  13. Ukrainian Issues in Geopolitical thought of the Twentieth and Twenty-First Centuries

    Directory of Open Access Journals (Sweden)

    Reginia-Zacharski Jacek

    2016-12-01

    Full Text Available Ukrainian lands in the twentieth and twenty-first centuries have been in proximity of great geopolitical changes several times. During that time the Ukrainian nation – due to various factors – encountered a number of “windows of opportunity” for achieving the realization of dreams about independence and national sovereignty. The author identified in the period considered four “general moments,” of which two have been completed successfully. The first of these occurred in 1990–1991, when for the first time in modern history, Ukrainians managed to achieve a lasting and relatively stable independence. The second of the “moments” – still unresolved – are events that began in the late autumn of 2013. The process, called “Revolution of Dignity”, represents a new quality in the history of the Ukrainian nation, therefore, that the Ukrainians have to defend the status quo (independence, territorial integrity, sovereignty, etc. but not to seek to achieve an independent being. The analysis leads to the conclusion that the ability of Ukrainians to achieve and maintain independence is largely a function of the relative power of the Russian state as measured with respect to the shape and quality of international relations.

  14. "For ever and ever": Child-raising, domestic workers and emotional labour in twentieth century Britain

    Directory of Open Access Journals (Sweden)

    Lucy Delap

    2011-07-01

    Full Text Available The relationships of physical and emotional labour which exist between children, parents and domestic workers are historically fluid. Different styles of parenting, discourses of social class, and material contexts of care have given rise to very diverse degrees of delegation of childcare to servants. Servants themselves have often invested emotionally in their relationships with children, and the relationship has clearly not been simply commodified in being delegated. However, the relationships that result have sometimes been troubled and ambivalent. A simple narrative of exploitation does little to capture the experiences of servants who cared for children, and the recent historiography of emotions and emotional labour can help to trace a fuller picture. In this paper, I examine the roles of laughter as a form of emotional expression that can shed light on the affects of care – the shared jokes, failed jokes and forms of mockery that characterised the management of servants by mothers who employed them, or the experiences of servants and children in late nineteenth and twentieth century servant-keeping houses.

  15. Theory versus Practice in the Twentieth-Century Search for the Ideal Anaesthetic Gas.

    Science.gov (United States)

    Rae, Ian D

    2016-02-01

    At the beginning of the twentieth century, an anaesthetist could choose between nitrous oxide, chloroform, and ether (diethyl ether) for the induction of painrelieving unconsciousness. By the end of century, the choice was between a small number of fluorinated aliphatic ethers such as Enflurane, Desflurane, and Sevoflurane, and (in some jurisdictions) the rare gas, xenon. Between these endpoints researchers had identified a surprisingly broad range of hydrocarbons, noble gases, organohalogens, and aliphatic ethers that possessed anaesthetic properties. None was entirely satisfactory, but clinicians at various times and in various places employed substances in each of these categories. Behind the search for new anaesthetic gases was a theory of action (Meyer- Overton theory) that was known to be inadequate, but as no alternative was strong enough to displace it the search continued on purely empirical grounds, while lip-service was paid to the theory. By the time a theory couched in more modern terms was proposed, a suite of modern anaesthetic gases was in place, and there have been no attempts to use that theory to drive a new search.

  16. Empowered objects, powerless subjects: citizenship, religion, and political representation in twentieth-century Cuba

    Directory of Open Access Journals (Sweden)

    Olivia Maria Gomes da Cunha

    2008-12-01

    Full Text Available [First paragraph] Measures of Equality: Social Science, Citizenship, and Race in Cuba, 1902-1940. Alejandra Marina Bronfman. Chapel Hill: University of North Carolina Press, 2004. xi + 234 pp. (Paper US$ 19.95 Afro-Cuban Religiosity, Revolution, and National Identity. Christine Ayorinde. Gainesville: University Press of Florida, 2004. ix + 283 pp. (Cloth US$ 59.95 In the last ten years, research topics such as race and nation have been privileged areas for the historical and anthropological understanding of Caribbean and Latin American societies. Regarding Cuba in particular, social scientists have dedicated important scholarship to these issues by mapping conceptions of citizenship and political representation, while situating them within a broader debate on the making of the new postcolonial and republican society at the beginning of the twentieth century. By pursuing different aims and following distinct approaches, Alejandra Bronfman and Christine Ayorinde have made contributions to this academic literature. Through divergent theoretical and methodological perspectives, both of their books explore alternative ways of interpreting the making of the nation founded upon a multiple and fluid rhetoric of race.

  17. The fire ant wars. Nature and science in the pesticide controversies of the late twentieth century.

    Science.gov (United States)

    Buhs, Joshua Blu

    2002-09-01

    This essay uses an approach borrowed from environmental history to investigate the interaction of science and nature in a late twentieth-century controversy. This debate, over the proper response to fire ants that had been imported into the American South accidentally and then spread across the region, pitted Rachel Carson and loosely federated groups of conservationists, scientists, and citizens against the U.S. Department of Agriculture. The analysis falls into three sections: an examination of the natural history of the ants; an examination of the views of the competing factions; and an examination of how those views, transformed into action, affected the natural world. Both sides saw the ants in terms of a constellation of beliefs about the relationship between nature, science, and democracy. As various ideas were put into play, they interacted with the natural history of the insects in unexpected ways--and with consequences for the cultural authority of the antagonists. Combining insights from the history of science and environmental history helps explain how scientists gain and lose cultural authority and, more fundamentally, allows for an examination of how nature can be integrated into the history of science.

  18. Dark, bloody and savage: Twentieth-century European violence and its narratives

    Directory of Open Access Journals (Sweden)

    Rodrigo, Javier

    2014-12-01

    Full Text Available This paper looks at major European twentieth-century narratives and interpretations that have seen it as an age of violence, terror and genocide. Using examples from historiographical debate and the analysis of specific historical processes (including the debates on genocide, concentrationary systems, civil wars and the Holocaust, it addresses both the characteristics of those narratives and some of their limitations and conceptual edges. Finally, the conceptual proposal put forward seeks to analyze, through historical contingency, continuities and discontinuities in the history of European collective violence.Este artículo propone una mirada a algunas de las grandes narrativas e interpretaciones sobre el siglo XX europeo que lo han visto como una centuria de violencia, terror y genocidio. A través de algunos ejemplos de debates historiográficos y de análisis de procesos históricos concretos (como los debates sobre el genocidio, los sistemas concentracionarios, las guerras civiles o el Holocausto, se abordan tanto las características de esas narrativas como algunos de sus límites y aristas. Al final, se adelanta una propuesta conceptual para analizar desde la contingencia histórica las continuidades y discontinuidades en la historia de la violencia colectiva europea.

  19. Are We Them? Textual and Literary Representations of the Chinese in Twentieth-Century Thailand

    Directory of Open Access Journals (Sweden)

    Thak Chaloemtiarana

    2014-12-01

    Full Text Available King Vajiravudh famously published an essay titled Jews of the Orient in 1914 demonizing the Chinese in Siam as ingrates and parasites. The local Chinese became the “Other Within” in the Thai nation that the king was trying to establish. Whether his reaction to the local Chinese was fueled by ire over the recent strike by the Chinese which paralyzed Bangkok, or a reflection of his English education and exposure to European anti-Semitism, is not the focus of my concern. My interest for this exercise is to study how the Chinese in Siam/Thailand are portrayed in Thai language texts, that is, prose fiction and non-fiction produced in the twentieth century (I will not include related areas such as movies, television drama, music, and cartoons. This study does not involve an exhaustive review of all texts but will focus on a few well-known and popular ones. I would like to know whether King Vajiravudh’s portrayal of the Chinese is reflected in subsequent literary production or muted by other realities that existed in Thai society, and how the production of texts on the local Chinese changed over time. More importantly, I am very curious to know how this issue is played out in neighboring countries, especially the Philippines, Indonesia, Malaysia, Burma, Laos, and Cambodia, countries where the “assimilation” of the Chinese into the majority culture happens in varying degrees.

  20. Writing the history of virology in the twentieth century: Discovery, disciplines, and conceptual change.

    Science.gov (United States)

    Méthot, Pierre-Olivier

    2016-10-01

    Concerned with the study of viruses and the diseases they cause, virology is now a well-established scientific discipline. Whereas aspects of its history from the late nineteenth to the mid-twentieth century have often been recounted through a number of detailed case studies, few general discussions of the historiography of virology have been offered. Looking at the ways in which the history of virology has been told, this article examines a number of debates among scientists and historians of biology and show how they are based on a different understanding of notions such as "discipline", of processes such as "scientific discovery" as well as on distinct views about what the history of science is and how it should be written (the opposition between "longue durée" and "micro-history" or between history of "concepts" versus "experimental methods"). The analysis provided here also suggests that a richer historiography of virology will require looking at the variations over time of the relations between conceptual, technological, and institutional factors that fostered its development at the intersection of several other scientific fields in the life sciences.

  1. The campus in the twentieth century: The urban campus in Chicago from 1890 to 1965

    Directory of Open Access Journals (Sweden)

    Marco Giliberti

    2011-01-01

    Full Text Available After the Civil War, when socio political reorganisation was urgently needed, American universities contributed to the process of re establishing the internal equilibrium of power within the nation. Thus an attempt was made to reinforce the political parties and develop regions as politically discrete territorial entities that were relatively manageable. In the twentieth century the effect of this policy of local centralisation at the regional level, in conjunction with the opportunity offered by the need to develop more effective city governance, was translated into the awareness that a major contribution of academia to politics is to help re establish the parameters of governability for the entire country. With the goal of documenting and exploring some key relations between campus plans and city planning in Chicago, this paper illustrates a number of campus plans and planning strategies in which “the city” can be thought of as a metonym for the entire society. Nexuses between campus and city planning can be revealed from the creation of the campus of the University of Chicago in 1890 to the first half of the 1960s.

  2. The German genius Europe's third renaissance, the second scientific revolution, and the twentieth century

    CERN Document Server

    Watson, Peter

    2010-01-01

    Peter Watson's virtuoso sweep through modern German thought and culture, from 1750 to the present day, will challenge and confound both the stereotypes the world has of Germany and those that Germany has of itself. From the end of the Baroque era and the death of Bach to the rise of Hitler in 1933, Germany was transformed from a poor relation among Western nations into a dominant intellectual and cultural force—more creative and influential than France, Britain, Italy, Holland, and the United States. In the early decades of the twentieth century, German artists, writers, scholars, philosophers, scientists, and engineers were leading their freshly unified country to new and unimagined heights. By 1933, Germans had won more Nobel Prizes than any other nationals, and more than the British and Americans combined. Yet this remarkable genius was cut down in its prime by Adolf Hitler and his disastrous Third Reich—a brutal legacy that has overshadowed the nation's achievements ever since. How did the Germans t...

  3. Decadal potential predictability of upper ocean heat content over the twentieth century

    Science.gov (United States)

    Li, Shujun; Zhang, Liping; Wu, Lixin

    2017-02-01

    The statistical method, Average Predictability Time (APT) decomposition, is used in the present paper to estimate the decadal predictability of upper ocean heat content over the global ocean, North Pacific and North Atlantic, respectively. The twentieth century simulations from CMIP5 outputs are the main data sources in this study. On global scale, the leading predictable component is characterized by a warming trend over the majority of oceans, which is related to the anthropogenic forced response. The second predictable component has significant loadings in the North Atlantic, especially in the subtropical region, which originates from the Atlantic Multidecadal Oscillation (AMO) predictability. To separate interactions among different ocean basins, we further maximize APT in individual North Pacific and North Atlantic oceans. It is found that the second and the third predictable component in North Pacific are significantly correlated with the well-known North Pacific Gyre Oscillation mode and the Pacific Decadal Oscillation respectively. Upper limit prediction skill of these two components are on the order of 6 years. In contrast, the most predictable component derived from the North Atlantic features an AMO-like spatial structure with its prediction skill up to 18 years, while the basin mode due to global warming only exists as the third component. This indicates the interdecadal variability in the North Atlantic is strong enough to mask the anthropogenic climate signals. Furthermore, predictability in the real world is also investigated and compared with model results by using observation-based data.

  4. Economic performance and public concerns about social class in twentieth-century books.

    Science.gov (United States)

    Chen, Yunsong; Yan, Fei

    2016-09-01

    What is the association between macroeconomic conditions and public perceptions of social class? Applying a novel approach based on the Google Books N-gram corpus, this study addresses the relationship between public concerns about social class and economic conditions throughout the twentieth century. The usage of class-related words/phrases, or "literary references to class," in American English-language books is related to US economic performance and income inequality. The findings of this study demonstrate that economic conditions play a significant role in literary references to class throughout the century, whereas income inequality does not. Similar results are obtained from further analyses using alternative measures of class concerns as well as different corpora of English Fiction and the New York Times. We add to the social class literature by showing that the long-term temporal dynamics of an economy can be exhibited by aggregate class concerns. The application of massive culture-wide content analysis using data of unprecedented size also represents a contribution to the literature. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Hungarian Population Discourses in the Twentieth Century: The Problem of Declining Birth Rates

    Directory of Open Access Journals (Sweden)

    Ildikó Szántó

    2016-01-01

    Full Text Available Falling birth rates had already been recorded as early as the late-eighteenth century in south-western Hungary in the Ormánság. Population loss from low birth rate remained one of the main topics writers and sociologists focused on in the twentieth century. The issue of Hungarian population decline was highlighted among the social ills in the interwar period, which was one of several subjects that divided intellectuals into ‘populists’ and ‘urbanites’. Following the impact of the low birth rate figures in the 1960s, the populists’ views of the 1930s resurfaced in public discourse in the 1960s and 1970s and up to the present day. The concern about the increasing trend of single-child families in rural settlements as well as in urban areas appeared in the various works of Hungarian writers and journalists throughout the previous century. The present paper intends to focus on the intellectual background to the public debates on the population issue, outlining the accounts of the interwar ‘village explorers’ briefly, and the way they are related to the pre-Second World War populist movement. Finally the reappearance of the debates between populists and non-populists of the 1970s is discussed, a debate that is still continuing.

  6. Experiments and Research Programmes. Revisiting Vitalism/Non-Vitalism Debate in Early Twentieth Century

    Directory of Open Access Journals (Sweden)

    Bijoy MUKHERJEE

    2012-06-01

    Full Text Available Debates in the philosophy of science typically take place around issues such as realism and theory change. Recently, the debate has been reformulated to bring in the role of experiments in the context of theory change. As regards realism, Ian Hacking’s contribution has been to introduce ‘intervention’ as the basis of realism. He also proposed, following Imre Lakatos, to replace the issue of truth with progress and rationality. In this context we examine the case of the vitalism — reductionism debate in biology inspired by the works of Indian physicist-turned-biologist Jagadish Chandra Bose (1858–1937, in the early twentieth century. Both camps had their characteristic hardcores. Vitalists led by John S. Burdon-Sanderson and Augustus D. Waller accepted religious metaphysics to support their research programme, which ultimately degenerated. Bose worked more with the ideals of science such as Occam’s razor, large-scale systematization of phenomena and novel prediction. I argue that his religious metaphysics, instead of acting as a protective shield, helped him to consolidate his position and allowed further problem shift resulting in a research programme that involved consciousness too. His research programme remains relevant even today.

  7. Using the Twentieth Century Reanalysis to assess climate variability for the European wind industry

    Science.gov (United States)

    Bett, Philip E.; Thornton, Hazel E.; Clark, Robin T.

    2017-01-01

    We characterise the long-term variability of European near-surface wind speeds using 142 years of data from the Twentieth Century Reanalysis (20CR), and consider the potential of such long-baseline climate data sets for wind energy applications. The low resolution of the 20CR would severely restrict its use on its own for wind farm site-screening. We therefore perform a simple statistical calibration to link it to the higher-resolution ERA-Interim data set (ERAI), such that the adjusted 20CR data has the same wind speed distribution at each location as ERAI during their common period. Using this corrected 20CR data set, wind speeds and variability are characterised in terms of the long-term mean, standard deviation and corresponding trends. Many regions of interest show extremely weak trends on century timescales, but contain large multidecadal variability. Since reanalyses such as ERAI are often used to provide the background climatology for wind farm site assessments, but contain only a few decades of data, our results can be used as a way of incorporating decadal-scale wind climate variability into such studies, allowing investment risks for wind farms to be reduced.

  8. Contributions to a genealogy of democracy in the twentieth century starting from the opposition Kelsen/Schmitt.

    Directory of Open Access Journals (Sweden)

    Andrés Fortunato

    2014-12-01

    Full Text Available In this work I analyze the theories of Carl Schmitt and Hans Kelsen of democracy in the light of the weberian topic of rationalization. My thesis is that this counterpoint does not escape the contemporary split that characterizes the nineteenth century modernity and continues in the twentieth century. At last, I’ll maintain that the political manifestation of this aporeticalbackground –over which one must understand the challenge of democracy– is what Schmitt calls the total State.

  9. Thermal comfort in twentieth-century architectural heritage: Two houses of Le Corbusier and André Wogenscky

    OpenAIRE

    Ignacio Requena-Ruiz

    2016-01-01

    International audience; The study of the relationship of climate and indoor thermal environments in architecture is essential to understand the inhabitants' sensory perception. This is even more relevant when working in the existing housing stock in view of the evolution of the twentieth-century heritage preservation and the problem of adapting these buildings to our current comfort and environmental criteria. The current article aims to develop a fair and balanced understanding of the approa...

  10. Lisa K. Perdigao. From Modernist Entombment to Postmodernist Exhumation Dead Bodies in Twentieth-Century American Fiction.

    Directory of Open Access Journals (Sweden)

    Ben Robbins

    2012-04-01

    Full Text Available Lisa K. Perdigao’s monograph titled From Modernist Entombment to Postmodernist Exhumation, seeks to offer a comprehensive study of the corpse as represented in American fiction of the twentieth century. Perdigao explores how novelists from a range of time periods and traditions use dead bodies as a device that is revealing of the wider formal ambitions of narrative. In her introduction, Perdigao sets out the theoretical framework on which her study is based. She draws on poststructuralist the...

  11. Antarctic station-based seasonal pressure reconstructions since 1905: 2. Variability and trends during the twentieth century

    Science.gov (United States)

    Fogt, Ryan L.; Jones, Julie M.; Goergens, Chad A.; Jones, Megan E.; Witte, Grant A.; Lee, Ming Yueng

    2016-03-01

    The Antarctic seasonal station-based pressure reconstructions evaluated in our companion paper are evaluated here to provide additional knowledge on Antarctic pressure variability during the twentieth century. In the period from 1905 to 1956, we find that the Hadley Centre gridded sea level pressure data set compared the best with our reconstructions, perhaps due to similar methods to estimate pressure without direct observations. The primary focus on the twentieth century Antarctic pressure variability was in summer and winter, as these were the seasons with the highest reconstruction skill. In summer, there is considerable interannual variability that was spatially uniform across all of Antarctica. Notable high pressure anomalies were found in the summers of 1911/1912 and 1925/1926; both summers correspond to negative phases of the Southern Annular Mode as well as El Niño events in the tropical Pacific. In addition, negative summer pressure trends during the last ~40 years across all of Antarctica are unique in the context of 30 year trends throughout the entire twentieth century, suggesting a strong component of anthropogenic forcing on the recent summer trends. In contrast, mean winter pressure is less variable from year to year during the early twentieth century, and there is less similarity between the pressure variations along the Antarctic Peninsula compared to the rest of the continent. No significant pressure trends were found consistently across all Antarctica (although some significant regional trends can be identified), and low-frequency, multidecadal-scale variability appears to dominate the historical pressure variations in this season.

  12. Writing History of Buddhist Thought in the Twentieth Century: Yinshun (1906-2005 in the Context of Chinese Buddhist Historiography

    Directory of Open Access Journals (Sweden)

    Marcus Bingenheimer

    2015-02-01

    Full Text Available Venerable Yinshun 印 順 (1906–2005 was the eminent scholar-monk in twentieth-century Chinese Buddhism. This paper is about his historiographical practice and tries to outline his position in Chinese Buddhist historiography especially in reference to the Song dynasty historian Zhipan 志磐 (thirteenth century. It tries to answer the question in what ways Yinshun can be said to have modernized Buddhist historiography for Chinese Buddhism.

  13. Some doctors of medicine who published optometry books and played significant roles in early twentieth century optometric education.

    Science.gov (United States)

    Goss, David A

    2011-01-01

    This paper provides brief profiles of four doctors of medicine who wrote books for optometrists and who were faculty members in, and/or directors of, optometry schools in the early twentieth century. Those studied were Thomas G. Atkinson (1870-1946), Marshall B. Ketchum (1856-1937), Joseph I. Pascal (1890-1955), and Clarence W. Talbot (1883-1958). The content of the books they wrote is also discussed.

  14. Software Engineering Laboratory Series: Proceedings of the Twentieth Annual Software Engineering Workshop

    Science.gov (United States)

    1995-01-01

    The Software Engineering Laboratory (SEL) is an organization sponsored by NASA/GSFC and created to investigate the effectiveness of software engineering technologies when applied to the development of application software. The activities, findings, and recommendations of the SEL are recorded in the Software Engineering Laboratory Series, a continuing series of reports that includes this document.

  15. NASA's geostationary communications platform program

    Science.gov (United States)

    Ramler, J.; Durrett, R.

    1984-01-01

    This paper reviews recent trends in communications satellites and explains NASA's current interest in geostationary communications platforms. Large communications platforms capable of supporting multiple payloads with common utilities have been examined in a number of studies since 1974 and appear to offer a number of potential advantages. In 1981, an Industry Briefing and Workshop sponsord by NASA focused on the institutional, operational and technical issues that will influence the implementation of geostationary platforms. The workshop identified numerous issues and problem areas that needed more detailed study. To address the issues/problems identified, a NASA geostationary communications platform program has been developed. This program is described, focusing on the initial studies to be performed.

  16. Tissue grown in NASA Bioreactor

    Science.gov (United States)

    1998-01-01

    Cells from kidneys lose some of their special features in conventional culture but form spheres replete with specialized cell microvilli (hair) and synthesize hormones that may be clinically useful. Ground-based research studies have demonstrated that both normal and neoplastic cells and tissues recreate many of the characteristics in the NASA bioreactor that they display in vivo. Proximal kidney tubule cells that normally have rich apically oriented microvilli with intercellular clefts in the kidney do not form any of these structures in conventional two-dimensional monolayer culture. However, when normal proximal renal tubule cells are cultured in three-dimensions in the bioreactor, both the microvilli and the intercellular clefts form. This is important because, when the morphology is recreated, the function is more likely also to be rejuvenated. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  17. Tissue grown in NASA Bioreactor

    Science.gov (United States)

    1998-01-01

    Cells from kidneys lose some of their special features in conventional culture but form spheres replete with specialized cell microvilli (hair) and synthesize hormones that may be clinically useful. Ground-based research studies have demonstrated that both normal and neoplastic cells and tissues recreate many of the characteristics in the NASA bioreactor that they display in vivo. Proximal kidney tubule cells that normally have rich apically oriented microvilli with intercellular clefts in the kidney do not form any of these structures in conventional two-dimensional monolayer culture. However, when normal proximal renal tubule cells are cultured in three-dimensions in the bioreactor, both the microvilli and the intercellular clefts form. This is important because, when the morphology is recreated, the function is more likely also to be rejuvenated. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC).

  18. NASA SBIR product catalog, 1990

    Science.gov (United States)

    Schwenk, F. Carl; Gilman, J. A.

    1990-01-01

    Since 1983 the NASA Small Business Innovation Research (SBIR) program has benefitted both the agency and the high technology small business community. By making it possible for more small businesses to participate in NASA's research and development, SBIR also provides opportunities for these entrepreneurs to develop products which may also have significant commercial markets. Structured in three phases, the SBIR program uses Phase 1 to assess the technical feasibility of novel ideas proposed by small companies and Phase 2 to conduct research and development on the best concepts. Phase 3, not funded by SBIR, is the utilization and/or commercialization phase. A partial list of products of NASA SBIR projects which have advanced to some degree into Phase 3 are provided with a brief description.

  19. Do blood-borne calcifying nanoparticles self-propagate?

    Directory of Open Access Journals (Sweden)

    Grace Mathew

    2008-06-01

    Full Text Available Grace Mathew1, David S McKay2, Neva Çiftçioglu21Nanobac Pharmaceuticals Inc, Johnson Space Center, Houston, TX, USA; 2NASA Johnson Space Center, Houston, TX, USAAbstract: The nanotechnology industry is currently in the process of producing new nanoparticles. The biological activity of nanoparticles including adverse as well as beneficial effects tends to increase as their size decreases. The smaller the particles are, the greater their bioactivity and toxicity. Thus, one can easily conjecture the impact of a nanoparticle if it could also self-replicate. This in vitro study reveals the self-propagating ability of unique calcifying nanoparticles (CNP that can be as small as 50 nm in size and found in blood, blood products, and calcified soft tissues. Although specific detection techniques, morphological characteristics and biomineralizing properties of CNP are well established, their genomic information and self-propagating capability have always been challenged. The objective of this study is to document the propagation of CNP under physiological conditions, using inverted light microscopy (LM and the Biostation IM time-lapse imaging system. Their detailed morphological structure was examined using scanning (SEM and transmission (TEM electron microscopy. This present study, in conjunction with previous findings of metabolic activity, antibiotic sensitivity, antibody specificity, morphological aspects and infectivity, validates CNP as self-replicators. Therefore these sterile-filterable, blood-borne nanoparticles should be of concern to the nanomedicine industry.Keywords: calcifying nanoparticles, time-lapse photography, self-replication, apatite

  20. NASA, Engineering, and Swarming Robots

    Science.gov (United States)

    Leucht, Kurt

    2015-01-01

    This presentation is an introduction to NASA, to science and engineering, to biologically inspired robotics, and to the Swarmie ant-inspired robot project at KSC. This presentation is geared towards elementary school students, middle school students, and also high school students. This presentation is suitable for use in STEM (science, technology, engineering, and math) outreach events. The first use of this presentation will be on Oct 28, 2015 at Madison Middle School in Titusville, Florida where the author has been asked by the NASA-KSC Speakers Bureau to speak to the students about the Swarmie robots.

  1. NASA Software Engineering Benchmarking Effort

    Science.gov (United States)

    Godfrey, Sally; Rarick, Heather

    2012-01-01

    Benchmarking was very interesting and provided a wealth of information (1) We did see potential solutions to some of our "top 10" issues (2) We have an assessment of where NASA stands with relation to other aerospace/defense groups We formed new contacts and potential collaborations (1) Several organizations sent us examples of their templates, processes (2) Many of the organizations were interested in future collaboration: sharing of training, metrics, Capability Maturity Model Integration (CMMI) appraisers, instructors, etc. We received feedback from some of our contractors/ partners (1) Desires to participate in our training; provide feedback on procedures (2) Welcomed opportunity to provide feedback on working with NASA

  2. The NASA L3 Study

    Science.gov (United States)

    Stebbins, Robin

    2016-01-01

    The Astrophysics Implementation Plan calls for a minority role in L3, planned for launch in 2034. L3 The third large mission in ESAs Cosmic Visions 2015-2025 Programme NASA and ESA have been discussing a collaboration for 2 years Gravitational Observatory Advisory Team (GOAT) ESA study evaluating and recommend scientific performance tradeoffs, detection technologies, technology development activities, data analysis capabilities, schedule and cost US representatives: Guido Mueller, Mark Kasevich, Bill Klipstein, RTS Started in October 2014, concluding with a final report in late Marchor early April 2016. ESA solicited interest from ESA Member States in November 2015 NASA is continuing technology development support. ESA is restarting technology development activities.

  3. NASA Pathways Internship: Spring 2016

    Science.gov (United States)

    Alvarez, Oscar, III

    2016-01-01

    I was selected to contribute to the Data Systems and Handling Branch under the Avionics Flight Systems Division at the Lyndon B. Johnson Space Center in Houston, Texas. There I used my knowledge from school, as well as my job experience from the military, to help me comprehend my assigned project and contribute to it. With help from my mentors, supervisors, colleagues, and an excellent NASA work environment, I was able to learn, as well as accomplish, a lot towards my project. Not only did I understand more about embedded systems, microcontrollers, and low-level programming, I also was given the opportunity to explore the NASA community.

  4. NASA USRP Internship Final Report

    Science.gov (United States)

    Black, Jesse A.

    2010-01-01

    The purpose of this report is to describe the body of work I have produced as a NASA USRP intern in the spring 2010. My mentor during this time was Richard Birr and I assisted him with many tasks in the advanced systems group in the engineering design lab at NASA's Kennedy space center. The main priority was and scenario modeling for the FAA's next generation air traffic control system and also developing next generation range systems for implementation at Kennedy space center. Also of importance was the development of wiring diagrams for the portable communications terminal for the desert rats program.

  5. Quality of Spatial Entanglement Propagation

    CERN Document Server

    Reichert, Matthew; Fleischer, Jason W

    2016-01-01

    We explore, both experimentally and theoretically, the propagation dynamics of spatially entangled photon pairs (biphotons). Characterization of entanglement is done via the Schmidt number, which is a universal measurement of the degree of entanglement directly related to the non-separability of the state into its subsystems. We develop expressions for the terms of the Schmidt number that depend on the amplitude and phase of the commonly used double-Gaussian approximation for the biphoton wave function, and demonstrate migration of entanglement between amplitude and phase upon propagation. We then extend this analysis to incorporate both phase curvature in the pump beam and higher spatial frequency content of more realistic non-Gaussian wave functions. Specifically, we generalize the classical beam quality parameter $M^2$ to the biphotons, allowing the description of more information-rich beams and more complex dynamics. Agreement is found with experimental measurements using direct imaging and Fourier optics...

  6. Atmospheric propagation of THz radiation.

    Energy Technology Data Exchange (ETDEWEB)

    Wanke, Michael Clement; Mangan, Michael A.; Foltynowicz, Robert J.

    2005-11-01

    In this investigation, we conduct a literature study of the best experimental and theoretical data available for thin and thick atmospheres on THz radiation propagation from 0.1 to 10 THz. We determined that for thick atmospheres no data exists beyond 450 GHz. For thin atmospheres data exists from 0.35 to 1.2 THz. We were successful in using FASE code with the HITRAN database to simulate the THz transmission spectrum for Mauna Kea from 0.1 to 2 THz. Lastly, we successfully measured the THz transmission spectra of laboratory atmospheres at relative humidities of 18 and 27%. In general, we found that an increase in the water content of the atmosphere led to a decrease in the THz transmission. We identified two potential windows in an Albuquerque atmosphere for THz propagation which were the regions from 1.2 to 1.4 THz and 1.4 to 1.6 THz.

  7. Exact propagators in harmonic superspace

    Science.gov (United States)

    Kuzenko, Sergei M.

    2004-10-01

    Within the background field formulation in harmonic superspace for quantum N = 2 super-Yang-Mills theories, the propagators of the matter, gauge and ghost superfields possess a complicated dependence on the SU(2) harmonic variables via the background vector multiplet. This dependence is shown to simplify drastically in the case of an on-shell vector multiplet. For a covariantly constant background vector multiplet, we exactly compute all the propagators. In conjunction with the covariant multi-loop scheme developed in arxiv:hep-th/0302205, these results provide an efficient (manifestly N = 2 supersymmetric) technical setup for computing multi-loop quantum corrections to effective actions in N = 2 supersymmetric gauge theories, including the N = 4 super-Yang-Mills theory.

  8. Exact propagators in harmonic superspace

    CERN Document Server

    Kuzenko, S M

    2004-01-01

    Within the background field formulation in harmonic superspace for quantum N = 2 super Yang-Mills theories, the propagators of the matter, gauge and ghost superfields possess a complicated dependence on the SU(2) harmonic variables via the background vector multiplet. This dependence is shown to simplify drastically in the case of an on-shell vector multiplet. For a covariantly constant background vector multiplet, we exactly compute all the propagators. In conjunction with the covariant multi-loop scheme developed in hep-th/0302205, these results provide an efficient (manifestly N = 2 supersymmetric) technical setup for computing multi-loop quantum corrections to effective actions in N = 2 supersymmetric gauge theories, including the N = 4 super Yang-Mills theory.

  9. Flame Propagation Through Concentration Gradient

    Institute of Scientific and Technical Information of China (English)

    JunyaIINO; MitsuakiTANABE; 等

    2000-01-01

    The experiment was carried out in homogeneous propane-air mixture and in several concentration gradient of mixture.Igniter is put on the upper side of the combustion chamber,In concentration gradient experiment.ixture was ignited from lean side.An experimental study was conducted in a combustion chamber.The combustion chamber has glass windows for optical measurements at any side.For the measurement of distribution of fuel concentration,infraed absorption method using 3.39μm He-Ne laser was used,and for the observation of proagating flams,Schlieren method was employed.As a measurment result of flame propagation velocity and flammable limit,for a mixture of an identical local equivalence ratio.flame propagation velocity in concentration gradient is faster than that in homogeneous mixture,and rich flammable limit in concentration gradient shows a tendency to be higher than that in homogeneous mixture.

  10. Interprocedural Analysis with Lazy Propagation

    DEFF Research Database (Denmark)

    Jensen, Simon Holm; Møller, Anders; Thiemann, Peter

    2010-01-01

    We propose lazy propagation as a technique for flow- and context-sensitive interprocedural analysis of programs with objects and first-class functions where transfer functions may not be distributive. The technique is described formally as a systematic modification of a variant of the monotone...... framework and its theoretical properties are shown. It is implemented in a type analysis tool for JavaScript where it results in a significant improvement in performance....

  11. Sound Propagation around Underwater Seamounts

    Science.gov (United States)

    2009-02-01

    N00014-04-1-0124. Contents Table of Contents List of Figures List of Tables 1 Introduction 1.1 Hypotheses ................... 1.2 Experim ent...132 . . . . . . . 133 Chapter 1 Introduction Basin-scale acoustic propagation in the ocean has been utilized by tomography and teleme- try... magnetostriction , a process caused by magnetic forces acting on the core and back iron magnetic domains, and the square relationship between mechanical force and

  12. Soliton propagation in relativistic hydrodynamics

    CERN Document Server

    Fogaça, D A; 10.1016/j.nuclphysa.2007.03.104

    2013-01-01

    We study the conditions for the formation and propagation of Korteweg-de Vries (KdV) solitons in nuclear matter. In a previous work we have derived a KdV equation from Euler and continuity equations in non-relativistic hydrodynamics. In the present contribution we extend our formalism to relativistic fluids. We present results for a given equation of state, which is based on quantum hadrodynamics (QHD).

  13. Acoustic Propagation Modeling Using MATLAB

    Science.gov (United States)

    1993-09-01

    Acoustic propagation, transient waves, transfer function, linear systems theory 16. PRICE CODE 17. SECURITY CLASSIFICATION 13. SECURITY CLASSIFICATION 1...method of diffraction prediction. This report describes an ap- proach based on linear systems theory and the Fourier transform. The goal was to achieve a...differed by the use of linear systems theory . Linear systems theory revealed the importance of the total impulse response and its equivalence to the

  14. Hsp104 and prion propagation.

    Science.gov (United States)

    Romanova, Nina V; Chernoff, Yury O

    2009-01-01

    High-ordered aggregates (amyloids) may disrupt cell functions, cause toxicity at certain conditions and provide a basis for self-perpetuated, protein-based infectious heritable agents (prions). Heat shock proteins acting as molecular chaperones counteract protein aggregation and influence amyloid propagation. The yeast Hsp104/Hsp70/Hsp40 chaperone complex plays a crucial role in interactions with both ordered and unordered aggregates. The main focus of this review will be on the Hsp104 chaperone, a molecular "disaggregase".

  15. Clonal propagation of Pelargonium sidoides: A threatened ...

    African Journals Online (AJOL)

    Tommy

    2006-01-16

    Jan 16, 2006 ... vines length to assess suitable plant part for vegetative propagation of the species. Data were ... harvested from the wild (Cunningham, 1988; Lange, .... Hormones and Different Rootstocks on Rose Propagation Pakistan J.

  16. Propagation Techniques for Highland Bamboo (Arundinaria alpina ...

    African Journals Online (AJOL)

    larger scale plantation, six types of vegetative propagation materials ... (10 new shoots per propagule), along its stem length (at the upper, middle and butt ..... can be used to get starting materials for macro-propagation purposes so that mass.

  17. NASA IMAGESEER: NASA IMAGEs for Science, Education, Experimentation, and Research

    Science.gov (United States)

    Le Moigne, Jacqueline; Grubb, Thomas G.; Milner, Barbara C.

    2012-06-01

    A number of web-accessible databases, including medical, military or other image data, offer universities and other users the ability to teach or research new Image Processing techniques on relevant and well-documented data. However, NASA images have traditionally been difficult for researchers to find, are often only available in hard-to-use formats, and do not always provide sufficient context and background for a non-NASA Scientist user to understand their content. The new IMAGESEER (IMAGEs for Science, Education, Experimentation and Research) database seeks to address these issues. Through a graphically-rich web site for browsing and downloading all of the selected datasets, benchmarks, and tutorials, IMAGESEER provides a widely accessible database of NASA-centric, easy to read, image data for teaching or validating new Image Processing algorithms. As such, IMAGESEER fosters collaboration between NASA and research organizations while simultaneously encouraging development of new and enhanced Image Processing algorithms. The first prototype includes a representative sampling of NASA multispectral and hyperspectral images from several Earth Science instruments, along with a few small tutorials. Image processing techniques are currently represented with cloud detection, image registration, and map cover/classification. For each technique, corresponding data are selected from four different geographic regions, i.e., mountains, urban, water coastal, and agriculture areas. Satellite images have been collected from several instruments - Landsat-5 and -7 Thematic Mappers, Earth Observing -1 (EO-1) Advanced Land Imager (ALI) and Hyperion, and the Moderate Resolution Imaging Spectroradiometer (MODIS). After geo-registration, these images are available in simple common formats such as GeoTIFF and raw formats, along with associated benchmark data.

  18. NASA IMAGESEER: NASA IMAGEs for Science, Education, Experimentation and Research

    Science.gov (United States)

    Le Moigne, Jacqueline; Grubb, Thomas G.; Milner, Barbara C.

    2012-01-01

    A number of web-accessible databases, including medical, military or other image data, offer universities and other users the ability to teach or research new Image Processing techniques on relevant and well-documented data. However, NASA images have traditionally been difficult for researchers to find, are often only available in hard-to-use formats, and do not always provide sufficient context and background for a non-NASA Scientist user to understand their content. The new IMAGESEER (IMAGEs for Science, Education, Experimentation and Research) database seeks to address these issues. Through a graphically-rich web site for browsing and downloading all of the selected datasets, benchmarks, and tutorials, IMAGESEER provides a widely accessible database of NASA-centric, easy to read, image data for teaching or validating new Image Processing algorithms. As such, IMAGESEER fosters collaboration between NASA and research organizations while simultaneously encouraging development of new and enhanced Image Processing algorithms. The first prototype includes a representative sampling of NASA multispectral and hyperspectral images from several Earth Science instruments, along with a few small tutorials. Image processing techniques are currently represented with cloud detection, image registration, and map cover/classification. For each technique, corresponding data are selected from four different geographic regions, i.e., mountains, urban, water coastal, and agriculture areas. Satellite images have been collected from several instruments - Landsat-5 and -7 Thematic Mappers, Earth Observing-1 (EO-1) Advanced Land Imager (ALI) and Hyperion, and the Moderate Resolution Imaging Spectroradiometer (MODIS). After geo-registration, these images are available in simple common formats such as GeoTIFF and raw formats, along with associated benchmark data.

  19. Wave Propagation in Modified Gravity

    CERN Document Server

    Lindroos, Jan Ø; Mota, David F

    2015-01-01

    We investigate the propagation of scalar waves induced by matter sources in the context of scalar-tensor theories of gravity which include screening mechanisms for the scalar degree of freedom. The usual approach when studying these theories in the non-linear regime of cosmological perturbations is based on the assumption that scalar waves travel at the speed of light. Within General Relativity such approximation is good and leads to no loss of accuracy in the estimation of observables. We find, however, that mass terms and non-linearities in the equations of motion lead to propagation and dispersion velocities significantly different from the speed of light. As the group velocity is the one associated to the propagation of signals, a reduction of its value has direct impact on the behavior and dynamics of nonlinear structures within modified gravity theories with screening. For instance, the internal dynamics of galaxies and satellites submerged in large dark matter halos could be affected by the fact that t...

  20. SUMMARY REPORT OF THE DOE DIRECT LIQUEFACTION PROCESS DEVELOPMENT CAMPAIGN OF THE LATE TWENTIETH CENTURY

    Energy Technology Data Exchange (ETDEWEB)

    F.P. Burke; S.D. Brandes; D.C. McCoy; R.A. Winschel; D. Gray; G. Tomlinson

    2001-07-01

    Following the petroleum price and supply disruptions of 1973, the U.S. government began a substantial program to fund the development of alternative fuels. Direct coal liquefaction was one of the potential routes to alternative fuels. The direct coal liquefaction program was funded at substantial levels through 1982, and at much lower levels thereafter. Those processes that were of most interest during this period were designed to produce primarily distillate fuels. By 1999, U.S. government funding for the development of direct coal liquefaction ended. Now that the end of this campaign has arrived, it is appropriate to summarize the process learnings derived from it. This report is a summary of the process learnings derived from the DOE direct coal liquefaction process development campaign of the late twentieth century. The report concentrates on those process development programs that were designed to produce primarily distillate fuels and were largely funded by DOE and its predecessors in response to the petroleum supply and price disruptions of the 1970s. The report is structured as chapters written by different authors on most of the major individual DOE-funded process development programs. The focus of the report is process learnings, as opposed to, say, fundamental coal liquefaction science or equipment design. As detailed in the overview (Chapter 2), DOE's direct coal liquefaction campaign made substantial progress in improving the process yields and the quality of the distillate product. Much of the progress was made after termination by 1983 of the major demonstration programs of the ''first generation'' (SRC-II, H-Coal, EDS) processes.

  1. Slope processes and related risk appearance within the Icelandic Westfjords during the twentieth century

    Directory of Open Access Journals (Sweden)

    A. Decaulne

    2005-01-01

    Full Text Available In North-western Iceland, records of slope processes were increasing during the twentieth century. Few dramatic events during the last decades highlighted the danger due to slope dynamics, leaving local populations in a risk situation that was merely unknown before 1970. The recent snow-avalanche, debris-flow and rock-fall activity underlined that the most frequent processes are not these with the largest human impact. In fact, the most catastrophic events were the extreme ones, following directly from a low frequency and a high magnitude. The purpose of this paper is to draw a parallel history of natural hazard and residence spatial extension, for an accurate understanding of the present-day risk situation, as the population growth markedly increased during the same time. Different quantitative and qualitative methods are applied. Geomorphological investigations locate the main threaten areas, in the path of slope processes release evidences, i.e. suitable slope morphology and/or inherited/actual forms. By a collection of dating data, as historic records and lichenometrical analysis, the frequency of given magnitude events is known. Climatic analysis clarifies the triggering meteorological conditions of slope processes and offers an overview of climate fluctuation during the investigated period; wind speed and direction is critical to hazardous snow-avalanche departure and snowmelt is crucial for debris-flow release. The findings clearly indicate that a combination of spatial expansion of inhabited areas and a lack of slope processes knowledge at the expansion time led to a recent and progressive risk appearance due to snow avalanches (including slush flows, debris flows and rock fall in most towns and villages of North-western Iceland.

  2. Assessing the impact of vertical land motion on twentieth century global mean sea level estimates

    Science.gov (United States)

    Hamlington, B. D.; Thompson, P.; Hammond, W. C.; Blewitt, G.; Ray, R. D.

    2016-07-01

    Near-global and continuous measurements from satellite altimetry have provided accurate estimates of global mean sea level in the past two decades. Extending these estimates further into the past is a challenge using the historical tide gauge records. Not only is sampling nonuniform in both space and time, but tide gauges are also affected by vertical land motion (VLM) that creates a relative sea level change not representative of ocean variability. To allow for comparisons to the satellite altimetry estimated global mean sea level (GMSL), typically the tide gauges are corrected using glacial isostatic adjustment (GIA) models. This approach, however, does not correct other sources of VLM that remain in the tide gauge record. Here we compare Global Positioning System (GPS) VLM estimates at the tide gauge locations to VLM estimates from GIA models, and assess the influence of non-GIA-related VLM on GMSL estimates. We find that the tide gauges, on average, are experiencing positive VLM (i.e., uplift) after removing the known effect of GIA, resulting in an increase of 0.24 ± 0.08 mm yr-1 in GMSL trend estimates from 1900 to present when using GPS-based corrections. While this result is likely dependent on the subset of tide gauges used and the actual corrections used, it does suggest that non-GIA VLM plays a significant role in twentieth century estimates of GMSL. Given the relatively short GPS records used to obtain these VLM estimates, we also estimate the uncertainty in the GMSL trend that results from limited knowledge of non-GIA-related VLM.

  3. Vagabond Figures in Slovenian Visual Art and Literature at the Beginning of the Twentieth Century

    Directory of Open Access Journals (Sweden)

    Robert Simonišek

    2011-07-01

    Full Text Available The article explores the relationship between visual and literary motifs in Slovenian painting (and illustration, graphics, and drawing and literature (both prose and poetry at the beginning of the twentieth century. It uses examples to show the popularity and rich variety of vagabond figures and their transformations and reciprocity at the level of the painting/text. However, a distinctive feature of this article is that it places the subject within the context of hermeneutics, a method that has not been used in Slovenian art history. In addition, it also reveals the symbolic complexity of the vagabond figure in the context of writers, other works, and social-historical circumstances. The emphasis is placed on artists that showed enthusiasm for this figure as a subject during the Belle Époque and also those that followed the very popular bohemian lifestyle in their everyday lives. The reception of Slovenian folk and traditional motifs from the past produced visual and semantic oscillation in which the phenomena of vagabond figures were systematized and interpreted. Many painters (e.g., Gvidon Birolla, and Maksim Gaspari and writers (e.g., Oton Župančič, Cvetko Golar, and Ivan Cankar clung to the Slovenian tradition with romantic overtones and, in line with their artistic atmosphere, integrated vagabond figures into typical Slovenian landscapes or environments. Some of them followed Symbolism and modernized the figures with autobiographical references (e.g., Fran Tratnik. The situation among the youngest generation of artists in particular showed that they managed to “escape” from copying traditional motifs and instead used them in a modern form in the “here and now” (e.g., Ivan Cankar. The discrepancy between the lack of the vagabond theme in oil painting and strong diversification in illustration, drawing, graphics, and literature could be explained by consumers’ perceived difference between “high” and “popular” art.

  4. Metal Construction Toys of the Early Twentieth Century: Their Astronomical Applications

    Science.gov (United States)

    Rumstay, K. S.

    2004-12-01

    During the early twentieth century several toy manufacturers around the globe introduced construction toys in the form of sets of metal parts which could be assembled into a variety of models. The two most successful were the Erector Set, introduced in the United States by A.C. Gilbert in 1913, and the Meccano Set, patented in 1901 in England by Frank Hornby. Whereas the Erector Set never developed beyond being a child's toy, Hornby envisioned his Meccano system as providing a way to teach principles of mechanical engineering to young schoolboys. Indeed, his sets were first marketed under the name "Mechanics Made Easy", and were endorsed by Dr. H.S. Hele-Shaw, Head of the Engineering Department at Liverpool University. Popularity of the new Meccano sets spread throughout the world, spawning the formation of numerous amateur societies composed of adolescent boys and an increasing number of adult hobbyists. The variety of parts increased during the first third of the century, and increasingly sophisticated models were constructed and exhibited in competitive events. Among these were several clocks of remarkable accuracy, and at least one equatorial mounting for a small astronomical telescope. At the same time, many university science and engineering departments found these interchangeable metal parts invaluable in the construction of experimental apparatus. In 1934 a small-scale replica of Vannevar Bush's Differential Analyzer was constructed at the University of Manchester, and used for many years to perform mathematical computations. The introduction in 1928 of a flanged ring with 73 (a sub-multiple of 365) teeth allowed for construction of accurate orreries and astronomical clocks. The most remarkable of these was the Astronomical Clock constructed in the period 1924-1932 by M. Alexandre Rahm of Paris.

  5. Air pressure effects on sea level changes during the twentieth century

    Science.gov (United States)

    Piecuch, Christopher G.; Thompson, Philip R.; Donohue, Kathleen A.

    2016-10-01

    Interpretation of tide gauge data in terms sea level (η) and ocean dynamics requires estimates of air pressure (pa) to determine the ocean's isostatic response—the inverted barometer effect (ηib). Three gridded pa products (HadSLP2, NOAA-20CRv2, and ERA-20C) are used alongside meteorological station pa and tide gauge η records to evaluate the contribution of ηib to η changes over the twentieth century. Agreement between gridded products is better during more recent periods and over regions with good historical data coverage, whereas it is worse for earlier time periods or in ocean areas with poor observational data coverage. Comparison against station data reveals the presence of systematic errors in the gridded products, for example, such that uncertainties estimated through differencing the gridded products underestimate the true errors by roughly 40% on interannual and decadal time scales. Notwithstanding such correlated errors, gridded products are still useful for interpretation of tide gauge data. Removing gridded estimates of ηib from η records reduces spatial variance in centennial trends across tide gauges by 10-30%, formal errors in centennial trends from individual gauges by ˜5%, and the temporal variance in detrended records by 10-15% on average (depending on choice of gridded product). Results here advocate for making the ηib correction to tide gauge records in studies of ocean circulation and global η over long, multidecadal, and centennial time scales using an ensemble mean taken across several gridded ηib products.

  6. Urania in the Marketplace: Astronomical Imagery in Early Twentieth-Century Advertizing

    Science.gov (United States)

    Rumstay, Kenneth S.

    2010-01-01

    The pages of popular magazines such as Sky and Telescope and Astronomy are filled with advertisements for telescopes and other equipment. However, during the past century astronomical imagery has been widely used to promote distinctly non-astronomical products and services. One of the earliest and most famous examples is the 1893 Chicago newspaper advertisement for Kirk's Soap, which was inspired by the opening of the Yerkes Observatory. A survey of popular magazines published in America during the first half of the twentieth century suggests that these advertisements fall into four categories: 1) Astronomy is universally regarded as an exact and precise science. Manufacturers of mechanical devices may employ images of telescopes or astronomers at work to suggest that their products meet these same standards of quality. This was primarily the case with makers of automobiles and automotive products, although the Longines Watch Company ran an extensive series of ads featuring observatories. 2) The heavens induce a sense of wonder in most people, and advertisers may locate their products in an a celestial setting to give them an otherworldly flavor. 3) Astronomical observatories themselves are viewed as exotic settings, and have provided backgrounds for automotive and travel ads. They may also appear in advertisements for products used in their construction. 4) Finally, newsworthy astronomical events will inspire advertisers to associate their products with that event, in order to capitalize upon the publicity. This was particularly true in the case of the 1910 passage of Halley's Comet and the 1948 opening of the 200-inch Hale telescope at Mt. Palomar. Examples of magazine advertisements from each category are presented for comparison. This work was supported by a faculty development grant from Valdosta State University.

  7. Materials for the investigation of The Seismicity Of Algeria And Adjacent Regions during the twentieth century

    Directory of Open Access Journals (Sweden)

    D. Benouar

    1994-06-01

    Full Text Available Dr. Benouar presents a full and integrated study of the recent seismicity of Algeria and adjacent regions during the twentieth century. He has amassed an impressive amount of macroseismic information pertaining to individual earthquakes, which he combines with instrumental information to reassess the origin parameters of each event. In any compilation of earthquakes it is the additional information beyond the bare accumulation of figures and facts that adds interest and social understanding to the scientific appreciation of the earthquakes themselves. For this it is necessary to know the local conditions, and Dr. Benouar brings out for us very vivid1y the differences between reporting procedures at different times this century, and the ensuing difficulties. It would be most difficult for an outsider to gather the information he presents, and he makes good use of his knowledge of his native land, as well as his professional training as an engineer. We thus learn of the reluctance of the colonial powers to report on damage or casualties outside those inflicted on the expatriate community, and the general difficulties of finding information about earthquakes that occurred during the wars of independence, at a time when effects of even major earthquakes were sometimes minor compared to those of the war itself. He also does not spare us details of political difficulties that arose during periods of reconstruction following recent earthquakes. This work is not restricted, however, to description. He examines the underlying tectonics of the area and deduces estimates of hazard and risk in various parts of the country. He then proceeds to examine the engineering consequences and discuss future needs for building codes and civil protection. Dr. Benouar has produced a work which could well form a model for those wishing to undertake comprelzensive studies of seismicity of other areas, and the measures needed to reduce the effects of catastrophic

  8. Calculations of precursor propagation in dispersive dielectrics.

    Energy Technology Data Exchange (ETDEWEB)

    Bacon, Larry Donald

    2003-08-01

    The present study is a numerical investigation of the propagation of electromagnetic transients in dispersive media. It considers propagation in water using Debye and composite Rocard-Powles-Lorentz models for the complex permittivity. The study addresses this question: For practical transmitted spectra, does precursor propagation provide any features that can be used to advantage over conventional signal propagation in models of dispersive media of interest? A companion experimental study is currently in progress that will attempt to measure the effects studied here.

  9. Confining crack propagation in defective graphene.

    Science.gov (United States)

    López-Polín, Guillermo; Gómez-Herrero, Julio; Gómez-Navarro, Cristina

    2015-03-11

    Crack propagation in graphene is essential to understand mechanical failure in 2D materials. We report a systematic study of crack propagation in graphene as a function of defect content. Nanoindentations and subsequent images of graphene membranes with controlled induced defects show that while tears in pristine graphene span microns length, crack propagation is strongly reduced in the presence of defects. Accordingly, graphene oxide exhibits minor crack propagation. Our work suggests controlled defect creation as an approach to avoid catastrophic failure in graphene.

  10. Japanese propagation experiments with ETS-5

    Science.gov (United States)

    Ikegami, Tetsushi

    1989-01-01

    Propagation experiments for maritime, aeronautical, and land mobile satellite communications were performed using Engineering Test Satellite-Five (ETS-5). The propagation experiments are one of major mission of Experimental Mobile Satellite System (EMSS) which is aimed for establishing basic technology for future general mobile satellite communication systems. A brief introduction is presented for the experimental results on propagation problems of ETS-5/EMSS.

  11. Fast Heat Pulse Propagation by Turbulence Spreading

    DEFF Research Database (Denmark)

    Naulin, Volker; Juul Rasmussen, Jens; Mantica, Paola

    2009-01-01

    The propagation of a cold pulse initiated by edge cooling in JET is compared to propagation of the heat wave originating from a modulation of the heating source roughly at mid radius. It is found that the propagation of the cold pulse is by far faster than what could be predicted on the basis of ...

  12. Fast Heat Pulse Propagation by Turbulence Spreading

    DEFF Research Database (Denmark)

    Naulin, Volker; Juul Rasmussen, Jens; Mantica, Paola

    2009-01-01

    The propagation of a cold pulse initiated by edge cooling in JET is compared to propagation of the heat wave originating from a modulation of the heating source roughly at mid radius. It is found that the propagation of the cold pulse is by far faster than what could be predicted on the basis of ...

  13. 47 CFR 80.767 - Propagation curve.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Propagation curve. 80.767 Section 80.767... MARITIME SERVICES Standards for Computing Public Coast Station VHF Coverage § 80.767 Propagation curve. The propagation graph, § 80.767 Graph 1, must be used in computing the service area contour. The graph...

  14. 49 CFR 195.111 - Fracture propagation.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Fracture propagation. 195.111 Section 195.111... PIPELINE Design Requirements § 195.111 Fracture propagation. A carbon dioxide pipeline system must be designed to mitigate the effects of fracture propagation....

  15. Design of a Ka-Band Propagation Terminal for Atmospheric Measurements in Polar Regions

    Science.gov (United States)

    Houts, Jacquelynne R.; Nessel, James A.; Zemba, Michael J.

    2016-01-01

    This paper describes the design and performance of a Ka-Band beacon receiver developed at NASA Glenn Research Center (GRC) that will be installed alongside an existing Ka-Band Radiometer [2] located at the east end of the Svalbard Near Earth Network (NEN) complex. The goal of this experiment is to characterize rain fade attenuation to improve the performance of existing statistical rain attenuation models. The ground terminal developed by NASA GRC utilizes an FFT-based frequency estimation [3] receiver capable of characterizing total path attenuation effects due to gaseous absorption, clouds, rain, and scintillation by directly measuring the propagated signal from the satellite Thor 7.

  16. Design of a Ka-band Propagation Terminal for Atmospheric Measurements in Polar Regions

    Science.gov (United States)

    Houts, Jacquelynne R.; Nessel, James A.; Zemba, Michael J.

    2016-01-01

    This paper describes the design and performance of a Ka-Band beacon receiver developed at NASA Glenn Research Center (GRC) that will be installed alongside an existing Ka-Band Radiometer located at the east end of the Svalbard Near Earth Network (NEN) complex. The goal of this experiment is to characterize rain fade attenuation to improve the performance of existing statistical rain attenuation models. The ground terminal developed by NASA GRC utilizes an FFT-based frequency estimation receiver capable of characterizing total path attenuation effects due to gaseous absorption, clouds, rain, and scintillation by directly measuring the propagated signal from the satellite Thor 7.

  17. NASA Space Sciences Strategic Planning

    Science.gov (United States)

    Crane, Philippe

    2004-01-01

    The purpose of strategic planning roadmap is to:Fulfill the strategic planning requirements; Provide a guide to the science community in presenting research requests to NASA; Inform and inspire; Focus investments in technology and research for future missions; and Provide the scientific and technical justification for augmentation requests.

  18. NASA Programs in Space Photovoltaics

    Science.gov (United States)

    Flood, Dennis J.

    1992-01-01

    Highlighted here are some of the current programs in advanced space solar cell and array development conducted by NASA in support of its future mission requirements. Recent developments are presented for a variety of solar cell types, including both single crystal and thin film cells. A brief description of an advanced concentrator array capable of AM0 efficiencies approaching 25 percent is also provided.

  19. NASA Earth Science Education Collaborative

    Science.gov (United States)

    Schwerin, T. G.; Callery, S.; Chambers, L. H.; Riebeek Kohl, H.; Taylor, J.; Martin, A. M.; Ferrell, T.

    2016-12-01

    The NASA Earth Science Education Collaborative (NESEC) is led by the Institute for Global Environmental Strategies with partners at three NASA Earth science Centers: Goddard Space Flight Center, Jet Propulsion Laboratory, and Langley Research Center. This cross-organization team enables the project to draw from the diverse skills, strengths, and expertise of each partner to develop fresh and innovative approaches for building pathways between NASA's Earth-related STEM assets to large, diverse audiences in order to enhance STEM teaching, learning and opportunities for learners throughout their lifetimes. These STEM assets include subject matter experts (scientists, engineers, and education specialists), science and engineering content, and authentic participatory and experiential opportunities. Specific project activities include authentic STEM experiences through NASA Earth science themed field campaigns and citizen science as part of international GLOBE program (for elementary and secondary school audiences) and GLOBE Observer (non-school audiences of all ages); direct connections to learners through innovative collaborations with partners like Odyssey of the Mind, an international creative problem-solving and design competition; and organizing thematic core content and strategically working with external partners and collaborators to adapt and disseminate core content to support the needs of education audiences (e.g., libraries and maker spaces, student research projects, etc.). A scaffolded evaluation is being conducted that 1) assesses processes and implementation, 2) answers formative evaluation questions in order to continuously improve the project; 3) monitors progress and 4) measures outcomes.

  20. The NASA Fireball Network Database

    Science.gov (United States)

    Moser, Danielle E.

    2011-01-01

    The NASA Meteoroid Environment Office (MEO) has been operating an automated video fireball network since late-2008. Since that time, over 1,700 multi-station fireballs have been observed. A database containing orbital data and trajectory information on all these events has recently been compiled and is currently being mined for information. Preliminary results are presented here.

  1. NASA Science Served Family Style

    Science.gov (United States)

    Noel-Storr, Jacob; Mitchell, S.; Drobnes, E.

    2010-01-01

    Family oriented innovative programs extend the reach of many traditional out-of-school venues to involve the entire family in learning in comfortable and fun environments. Research shows that parental involvement is key to increasing student achievement outcomes, and family-oriented programs have a direct impact on student performance. Because families have the greatest influence on children's attitudes towards education and career choices, we have developed a Family Science program that provides families a venue where they can explore the importance of science and technology in our daily lives by engaging in learning activities that change their perception and understanding of science. NASA Family Science Night strives to change the way that students and their families participate in science, within the program and beyond. After three years of pilot implementation and assessment, our evaluation data shows that Family Science Night participants have positive change in their attitudes and involvement in science.  Even after a single session, families are more likely to engage in external science-related activities and are increasingly excited about science in their everyday lives.  As we enter our dissemination phase, NASA Family Science Night will be compiling and releasing initial evaluation results, and providing facilitator training and online support resources. Support for NASA Family Science Nights is provided in part through NASA ROSES grant NNH06ZDA001N.

  2. NASA's EOSDIS, Trust and Certification

    Science.gov (United States)

    Ramapriyan, H. K.

    2017-01-01

    NASA's Earth Observing System Data and Information System (EOSDIS) has been in operation since August 1994, managing most of NASA's Earth science data from satellites, airborne sensors, filed campaigns and other activities. Having been designated by the Federal Government as a project responsible for production, archiving and distribution of these data through its Distributed Active Archive Centers (DAACs), the Earth Science Data and Information System Project (ESDIS) is responsible for EOSDIS, and is legally bound by the Office of Management and Budgets circular A-130, the Federal Records Act. It must follow the regulations of the National Institute of Standards and Technologies (NIST) and National Archive and Records Administration (NARA). It must also follow the NASA Procedural Requirement 7120.5 (NASA Space Flight Program and Project Management). All these ensure that the data centers managed by ESDIS are trustworthy from the point of view of efficient and effective operations as well as preservation of valuable data from NASA's missions. Additional factors contributing to this trust are an extensive set of internal and external reviews throughout the history of EOSDIS starting in the early 1990s. Many of these reviews have involved external groups of scientific and technological experts. Also, independent annual surveys of user satisfaction that measure and publish the American Customer Satisfaction Index (ACSI), where EOSDIS has scored consistently high marks since 2004, provide an additional measure of trustworthiness. In addition, through an effort initiated in 2012 at the request of NASA HQ, the ESDIS Project and 10 of 12 DAACs have been certified by the International Council for Science (ICSU) World Data System (WDS) and are members of the ICSUWDS. This presentation addresses questions such as pros and cons of the certification process, key outcomes and next steps regarding certification. Recently, the ICSUWDS and Data Seal of Approval (DSA) organizations

  3. The NASA Carbon Monitoring System

    Science.gov (United States)

    Hurtt, G. C.

    2015-12-01

    Greenhouse gas emission inventories, forest carbon sequestration programs (e.g., Reducing Emissions from Deforestation and Forest Degradation (REDD and REDD+), cap-and-trade systems, self-reporting programs, and their associated monitoring, reporting and verification (MRV) frameworks depend upon data that are accurate, systematic, practical, and transparent. A sustained, observationally-driven carbon monitoring system using remote sensing data has the potential to significantly improve the relevant carbon cycle information base for the U.S. and world. Initiated in 2010, NASA's Carbon Monitoring System (CMS) project is prototyping and conducting pilot studies to evaluate technological approaches and methodologies to meet carbon monitoring and reporting requirements for multiple users and over multiple scales of interest. NASA's approach emphasizes exploitation of the satellite remote sensing resources, computational capabilities, scientific knowledge, airborne science capabilities, and end-to-end system expertise that are major strengths of the NASA Earth Science program. Through user engagement activities, the NASA CMS project is taking specific actions to be responsive to the needs of stakeholders working to improve carbon MRV frameworks. The first phase of NASA CMS projects focused on developing products for U.S. biomass/carbon stocks and global carbon fluxes, and on scoping studies to identify stakeholders and explore other potential carbon products. The second phase built upon these initial efforts, with a large expansion in prototyping activities across a diversity of systems, scales, and regions, including research focused on prototype MRV systems and utilization of COTS technologies. Priorities for the future include: 1) utilizing future satellite sensors, 2) prototyping with commercial off-the-shelf technology, 3) expanding the range of prototyping activities, 4) rigorous evaluation, uncertainty quantification, and error characterization, 5) stakeholder

  4. A Brief Historical Survey of Rocket Testing Induced Acoustic Environments at NASA SSC

    Science.gov (United States)

    Allgood, Daniel C.

    2012-01-01

    A survey was conducted of all the various rocket test programs that have been performed since the establishment of NASA Stennis Space Center. The relevant information from each of these programs were compiled and used to quantify the theoretical noise source levels using the NASA approved methodology for computing "acoustic loads generated by a propulsion system" (NASA SP ]8072). This methodology, which is outlined in Reference 1, has been verified as a reliable means of determining the noise source characteristics of rocket engines. This information is being provided to establish reference environments for new government/business residents to ascertain whether or not their activities will generate acoustic environments that are more "encroaching" in the NASA Fee Area. In this report, the designation of sound power level refers to the acoustic power of the rocket engine at the engine itself. This is in contrast to the sound pressure level associated with the propagation of the acoustic energy in the surrounding air. The first part of the survey documents the "at source" sound power levels and their dominant frequency bands for the range of engines tested at Stennis. The second part of the survey discusses how the acoustic energy levels will propagate non ]uniformly from the test stands. To demonstrate this, representative acoustic sound pressure mappings in the NASA Stennis Fee Area were computed for typical engine tests on the B ]1 and E ]1 test stands.

  5. Electromagnetic beam propagation in nonlinear media

    Institute of Scientific and Technical Information of China (English)

    V.V.Semak; M.N.Shneider

    2015-01-01

    We deduce a complete wave propagation equation that includes inhomogeneity of the dielectric constant and present this propagation equation in compact vector form. Although similar equations are known in narrow fields such as radio wave propagation in the ionosphere and electromagnetic and acoustic wave propagation in stratified media, we develop here a novel approach of using such equations in the modeling of laser beam propagation in nonlinear media. Our approach satisfies the correspondence principle since in the limit of zero-length wavelength it reduces from physical to geometrical optics.

  6. Tropospheric radiowave propagation beyond the horizon

    CERN Document Server

    Du Castel, François

    1966-01-01

    Tropospheric Radiowave Propagation Beyond the Horizon deals with developments concerning the tropospheric propagation of ultra-short radio waves beyond the horizon, with emphasis on the relationship between the theoretical and the experimental. Topics covered include the general conditions of propagation in the troposphere; general characteristics of propagation beyond the horizon; and attenuation in propagation. This volume is comprised of six chapters and begins with a brief historical look at the various stages that have brought the technique of transhorizon links to its state of developmen

  7. Recent Efforts in Advanced High Frequency Communications at the Glenn Research Center in Support of NASA Mission

    Science.gov (United States)

    Miranda, Felix A.

    2015-01-01

    This presentation will discuss research and technology development work at the NASA Glenn Research Center in advanced frequency communications in support of NASAs mission. An overview of the work conducted in-house and also in collaboration with academia, industry, and other government agencies (OGA) in areas such as antenna technology, power amplifiers, radio frequency (RF) wave propagation through Earths atmosphere, ultra-sensitive receivers, among others, will be presented. In addition, the role of these and other related RF technologies in enabling the NASA next generation space communications architecture will be also discussed.

  8. Propagation phenomena in real world networks

    CERN Document Server

    Fay, Damien; Gabryś, Bogdan

    2015-01-01

    Propagation, which looks at spreading in complex networks, can be seen from many viewpoints; it is undesirable, or desirable, controllable, the mechanisms generating that propagation can be the topic of interest, but in the end all depends on the setting. This book covers leading research on a wide spectrum of propagation phenomenon and the techniques currently used in its modelling, prediction, analysis and control. Fourteen papers range over topics including epidemic models, models for trust inference, coverage strategies for networks, vehicle flow propagation, bio-inspired routing algorithms, P2P botnet attacks and defences, fault propagation in gene-cellular networks, malware propagation for mobile networks, information propagation in crisis situations, financial contagion in interbank networks, and finally how to maximize the spread of influence in social networks. The compendium will be of interest to researchers, those working in social networking, communications and finance and is aimed at providin...

  9. Wave propagation and group velocity

    CERN Document Server

    Brillouin, Léon

    1960-01-01

    Wave Propagation and Group Velocity contains papers on group velocity which were published during the First World War and are missing in many libraries. It introduces three different definitions of velocities: the group velocity of Lord Rayleigh, the signal velocity of Sommerfeld, and the velocity of energy transfer, which yields the rate of energy flow through a continuous wave and is strongly related to the characteristic impedance. These three velocities are identical for nonabsorbing media, but they differ considerably in an absorption band. Some examples are discussed in the last chapter

  10. Trust Propagation in Small Worlds

    DEFF Research Database (Denmark)

    Gray, Elizabeth; Seigneur, Jean-Marc; Chen, Yong

    2003-01-01

    The possibility of a massive, networked infrastructure of diverse entities partaking in collaborative applications with each other increases more and more with the proliferation of mobile devices and the development of ad hoc networking technologies. In this context, traditional security measures...... do not scale well. We aim to develop trust-based security mechanisms using small world concepts to optimise formation and propagation of trust amongst entities in these vast networks. In this regard, we surmise that in a very large mobile ad hoc network, trust, risk, and recommendations can...

  11. Photon propagator in skewon electrodynamics

    CERN Document Server

    Itin, Yakov

    2015-01-01

    Electrodynamics with a local and linear constitutive law is used as a framework for models violating Lorentz covariance. The constitutive tensor of such a construction is irreducibly decomposed into three independent pieces. The principal part is the anisotropic generalisation of the standard electrodynamics. The two other parts, axion and skewon, represent non-classical modifications of electrodynamics. We derive the expression for the photon propagator in the Minkowski spacetime endowed with a skewon field. For a relatively small (antisymmetric) skewon field, a modified Coulom law is exhibited.

  12. Continuous propagation of microalgae. III.

    Science.gov (United States)

    Hanson, D. T.; Fredrickson, A. G.; Tsuchiya, H. M.

    1971-01-01

    Data are presented which give the specific photosynthetic rate and the specific utilization rates of urea and carbon dioxide as functions of specific growth rate for Chlorella. A mathematical model expresses a set of mass balance relations between biotic and environmental materials. Criteria of validity are used to test this model. Predictive procedures are complemented by a particular model of microbial growth. Methods are demonstrated for predicting substrate utilization rates, production rates of extracellular metabolites, growth limiting conditions, and photosynthetic quotients from propagator variables.

  13. [Bibliometry of biological systematics in Latin America during the twentieth century in three global databases].

    Science.gov (United States)

    Michán, Layla; Llorente-Bousquets, Jorge

    2010-06-01

    We present a review of the biological systematic research in Latin America during the twentieth century, applying a bibliometric analysis to the information contained in international databases with the largest number of biological records: Biosis (since 1969), CAB (since 1910) and Science Citation Index (since 1900), to recognize certain patterns and trends regarding the document production. We obtained 19079 documents and 1387 journals for Biosis, 14326 and 2537 for CAB, 3257 and 1636 for SCI. Of the documents, 54.6% related to new species, 15.3% dealt with morphology, 14.9% keys, 12.5% descriptions, 10.6% cases of synonymies, 6% new genera, 4.9% new geographical records, 23.6% geographical distribution, 4.2% redescriptions, and 3.6% with new nomenclatural combinations. The regions mentioned were South America with 11.9%, Central America with 4% and America (all) with 2.56%. Nineteen Latin American countries appear, whereas outside this region we found the United States of America with 12.6% of representation and Canada with 3%. Animals (65.6%) were the most studied taxa, which was 1.7 times higher than what was published for plants (37%), 11 times higher than fungi (6%) and nearly 30 times higher than microorganisms (2.3%). Out of the 155 journals that produced 66% of the papers, 76.5% were better represented in Biosis, 21.4% in CAB and 2% in SCI. Twenty-nine journals published 33% of the articles, the maximum number of records obtained was 69% for Biosis, CAB 24% and 6.9% for SCI, three (10.3%) are in biology, 11 (37.9%) in botany, 13 (44.8%) zoology, and two (6.9%) paleontology; eight of these journals (27.5%) were published in Latin America and twenty were indexed in the Science Citation Index. In the last two years more journals of the region that publish on taxonomy have been indexed, but their impact factor is still low. However, the impact factor of a number of Latin American journals that published biodiversity increased with time. Countries that are

  14. Forced and Unforced Variability of Twentieth Century North American Droughts and Pluvials

    Science.gov (United States)

    Cook, Benjamin I.; Cook, Edward R.; Anchukaitis, Kevin J.; Seager, Richard; Miller, Ron L.

    2010-01-01

    Research on the forcing of drought and pluvial events over North America is dominated by general circulation model experiments that often have operational limitations (e.g., computational expense, ability to simulate relevant processes, etc). We use a statistically based modeling approach to investigate sea surface temperature (SST) forcing of the twentieth century pluvial (1905-1917) and drought (1932-1939, 1948-1957, 1998-2002) events. A principal component (PC) analysis of Palmer Drought Severity Index (PDSI) from the North American Drought Atlas separates the drought variability into five leading modes accounting for 62% of the underlying variance. Over the full period spanning these events (1900-2005), the first three PCs significantly correlate with SSTs in the equatorial Pacific (PC 1), North Pacific (PC 2), and North Atlantic (PC 3), with spatial patterns (as defined by the empirical orthogonal functions) consistent with our understanding of North American drought responses to SST forcing. We use a large ensemble statistical modeling approach to determine how successfully we can reproduce these drought/pluvial events using these three modes of variability. Using Pacific forcing only (PCs 1-2), we are able to reproduce the 1948-1957 drought and 1905-1917 pluvial above a 95% random noise threshold in over 90% of the ensemble members; the addition of Atlantic forcing (PCs 1-2-3) provides only marginal improvement. For the 1998-2002 drought, Pacific forcing reproduces the drought above noise in over 65% of the ensemble members, with the addition of Atlantic forcing increasing the number passing to over 80%. The severity of the drought, however, is underestimated in the ensemble median, suggesting this drought intensity can only be achieved through internal variability or other processes. Pacific only forcing does a poor job of reproducing the 1932-1939 drought pattern in the ensemble median, and less than one third of ensemble members exceed the noise threshold

  15. The Strategic Petroleum Reserve: United States energy security, oil politics, and petroleum reserves policies in the twentieth century

    Science.gov (United States)

    Beaubouef, Bruce Andre

    The history of U.S. petroleum reserves policies in the twentieth century, including the Strategic Petroleum Reserve (SPR) program, provides a case study of the economic and political aspects of national security, and shows the ways in which the American political economy influences national security. One key problem plagued federal petroleum reserve programs and proposals throughout the twentieth century. In a political economy which traditionally placed strong emphasis upon the sanctity of private property and free markets, could the government develop an emergency petroleum reserve policy despite opposition from the private sector? Previous literature on the SPR and oil-stockpiling programs has largely disregarded the historical perspective, focusing instead upon econometric models, suggesting future oil-stockpiling policy options. This study will also make conclusions about the future of governmental oil-stockpiling policies, particularly with regard to the SPR program, but it will do so informed by a systematic history of the emergency petroleum reserve impulse in the twentieth century. Through a study of the emergency petroleum reserve impulse, one can see how the American political economy of oil and energy changed over the twentieth century. As petroleum became crucial to the military and then economic security of the United States, the federal government sought to develop emergency petroleum reserves first for the military, then for the civilian economy. But while the American petroleum industry could deliver the energy "goods" to American energy consumers at a reasonable price, the companies reigned supreme in the political equation. While that was true, federal petroleum reserve programs and proposals conflicted with and were overwhelmed by the historic American tradition of individual economic and private property rights. The depletion of American petroleum reserves changed that political equation, and the ensuing energy crises of the 1970s not only

  16. Maintaining Masculinity in Mid-Twentieth-Century American Psychology: Edwin Boring, Scientific Eminence, and the "Woman Problem".

    Science.gov (United States)

    Rutherford, Alexandra

    2015-01-01

    Using mid-twentieth-century American psychology as my focus, I explore how scientific psychology was constructed as a distinctly masculine enterprise and was navigated by those who did not conform easily to this masculine ideal. I show how women emerged as problems for science through the vigorous gatekeeping activities and personal and professional writings of disciplinary figurehead Edwin G. Boring. I trace Boring's intellectual and professional socialization into masculine science and his efforts to understand women's apparent lack of scientific eminence, efforts that were clearly undergirded by preexisting and widely shared assumptions about men's and women's capacities and preferences.

  17. Balkans as a cultural symbol in the Serbian music of the first half of the twentieth century

    Directory of Open Access Journals (Sweden)

    Milanović Biljana

    2008-01-01

    Full Text Available Focus on the internalization of Western images in the Balkans has special significance in researching Serbian art. The functioning of Balkanism as it overlapped and intersected with Orientalism is indicated in the text by an examination of the cases of Petar Konjović, Miloje Milojević and Josip Slavenski, the three significant composers working in Serbia during the first half of the twentieth century. Their modernistic projects present different metaphors of the Balkans. Nevertheless each of them is marked by desire to change the Balkan image into a 'positive' one and thus stands as a special voice for Serbian and regional placing in European competition for musical spaces.

  18. The return of the phoenix: the 1963 International Congress of Zoology and American zoologists in the twentieth century.

    Science.gov (United States)

    Johnson, Kristin

    2009-01-01

    This paper examines the International Congress of Zoology held in Washington D.C. in 1963 as a portrait of American zoologists' search for effective and rewarding relationships with both each other and the public. Organizers of the congress envisioned the congress as a last ditch effort to unify the disparate subdisciplines of zoology, overcome the barriers of specialization, and ward off the heady claims of more reductionist biologists. The problems zoologists faced as they worked to fulfill these ambitious goals illuminate some of the challenges faced by members of the naturalist tradition as they worked to establish disciplinary unity while seeking public support in the competitive world of twentieth century science.

  19. Salamanca’s theater and musical activity in the first quarter of twentieth century through the local press

    Directory of Open Access Journals (Sweden)

    Francisco José Álvarez García

    2011-06-01

    Full Text Available The theaters at the beginning of twentieth century are one of the main focuses in which condenses the musician-artistic activity of small and large Spanish cities. Salamanca could not be less and in the three capitals theaters “Liceo”, “Bretón” and “Moderno” we find a very rich musical activity like Zarzuelas, Concerts, Lyric Theatre, Tunas, etc., which will make to Salamanca the most important center of the music scene in the province until almost the Second Spanish Republic.

  20. Science and miscegenation in the early twentieth century: Edgard Roquette-Pinto's debates and controversies with US physical anthropology.

    Science.gov (United States)

    Souza, Vanderlei Sebastião de

    2016-01-01

    The article analyzes Brazilian anthropologist Edgard Roquette-Pinto's participation in the international debate that involved the field of physical anthropology and discussions on miscegenation in the first decades of the twentieth century. Special focus is on his readings and interpretations of a group of US anthropologists and eugenicists and his controversies with them, including Charles Davenport, Madison Grant, and Franz Boas. The article explores the various ways in which Roquette-Pinto interpreted and incorporated their ideas and how his anthropological interpretations took on new meanings when they moved beyond Brazil's borders.

  1. Proceedings of the US Nuclear Regulatory Commission twentieth water reactor safety information meeting; Volume 2, Severe accident research, Thermal hydraulics

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, A.J. [comp.] [Brookhaven National Lab., Upton, NY (United States)

    1993-03-01

    This three-volume report contains papers presented at the Twentieth Water Reactor Safety Information Meeting held at the Bethesda Marriott Hotel, Bethesda, Maryland, during the week of October 21--23, 1992. The papers describe progress and results of programs in nuclear safety research conducted in this country and abroad. Foreign participation in the meeting included 10 different papers presented by researchersfrom CEC, China, Finland, France, Germany, Japan, Spain and Taiwan. Selected papers have been processed separately for inclusion in the Energy Science and Technology Database.

  2. [The medical, social and institutional challenges resulting from poliomyelitis: comprehensive rehabilitation in Argentina in the mid-twentieth century].

    Science.gov (United States)

    Alvarez, Adriana

    2015-01-01

    Poliomyelitis on an epidemic scale gave rise to several challenges, one of which was the rehabilitation from the after-effects on many of the people who suffered from the disease. Paralysis and the ways it transformed the concept of physical rehabilitation (where the objective was only to restore the mobility of the affected muscles) and comprehensive rehabilitation that included social, educational and professional aspects in Argentina in the mid-twentieth century are the themes addressed in this article. It uses the methodology of institutional history that interacts in an ongoing manner with the history of health and disease.

  3. Family Life in Europe in the Twentieth Century/ Życie rodzinne w Europie w XX wieku

    Directory of Open Access Journals (Sweden)

    MARIE MAREČKOVÁ

    2012-01-01

    Full Text Available Family life in Europe has undergone many changes in the twentieth century. These include the lifestyle of women, their legal freedom, family relations, relations with partners, relations with the older generation, and relations with children. The position of women in society has also undergone many transformations. Problems remain, however, in the social and family policy of the state, as women engaged in the working process give preference to their own plans and their need for self-fulfi lment. The main goal of state family policy in the twenty-first century is, then, to ensure a harmonious balance between professional activity and family life.

  4. NASA 2010 Pharmacology Evidence Review

    Science.gov (United States)

    Steinberg, Susan

    2011-01-01

    In 2008, the Institute of Medicine reviewed NASA's Human Research Program Evidence in assessing the Pharmacology risk identified in NASA's Human Research Program Requirements Document (PRD). Since this review there was a major reorganization of the Pharmacology discipline within the HRP, as well as a re-evaluation of the Pharmacology evidence. This panel is being asked to review the latest version of the Pharmacology Evidence Report. Specifically, this panel will: (1) Appraise the descriptions of the human health-related risk in the HRP PRD. (2) Assess the relevance and comprehensiveness of the evidence in identifying potential threats to long-term space missions. (3) Assess the associated gaps in knowledge and identify additional areas for research as necessary.

  5. A Bioinformatics Facility for NASA

    Science.gov (United States)

    Schweighofer, Karl; Pohorille, Andrew

    2006-01-01

    Building on an existing prototype, we have fielded a facility with bioinformatics technologies that will help NASA meet its unique requirements for biological research. This facility consists of a cluster of computers capable of performing computationally intensive tasks, software tools, databases and knowledge management systems. Novel computational technologies for analyzing and integrating new biological data and already existing knowledge have been developed. With continued development and support, the facility will fulfill strategic NASA s bioinformatics needs in astrobiology and space exploration. . As a demonstration of these capabilities, we will present a detailed analysis of how spaceflight factors impact gene expression in the liver and kidney for mice flown aboard shuttle flight STS-108. We have found that many genes involved in signal transduction, cell cycle, and development respond to changes in microgravity, but that most metabolic pathways appear unchanged.

  6. Stokes examines NASA program management

    Science.gov (United States)

    Leath, Audrey T.

    As NASA gears up for another attempt at redesigning Space Station Freedom, some in Congress are wondering whether the space agency has learned any lessons from a number of costly past mistakes. Louis Stokes (D-Ohio), the new chairman of the House Appropriations Veterans Affairs, Housing and Urban Development, and Independent Agencies Subcommittee, held a hearing on March 17 to examine unanticipated cost growth in a variety of projects, including the space toilet, the advanced turbo pump for the shuttle, and the Mars Observer, as well as the space station. Stokes seemed well-suited to this oversight role, asking well-informed and probing questions rather than accusatory ones. The witnesses, NASA head Daniel Goldin and many of his top managers (most of whom were not in their present positions when the projects were initiated), analyzed past errors and offered useful measures for avoiding similar problems in the future.

  7. NASA's Earth Science Data Systems

    Science.gov (United States)

    Ramapriyan, H. K.

    2015-01-01

    NASA's Earth Science Data Systems (ESDS) Program has evolved over the last two decades, and currently has several core and community components. Core components provide the basic operational capabilities to process, archive, manage and distribute data from NASA missions. Community components provide a path for peer-reviewed research in Earth Science Informatics to feed into the evolution of the core components. The Earth Observing System Data and Information System (EOSDIS) is a core component consisting of twelve Distributed Active Archive Centers (DAACs) and eight Science Investigator-led Processing Systems spread across the U.S. The presentation covers how the ESDS Program continues to evolve and benefits from as well as contributes to advances in Earth Science Informatics.

  8. NASA's Radioisotope Power Systems - Plans

    Science.gov (United States)

    Hamley, John A.; Mccallum, Peter W.; Sandifer, Carl E., II; Sutliff, Thomas J.; Zakrajsek, June F.

    2015-01-01

    NASA's Radioisotope Power Systems (RPS) Program continues to plan and implement content to enable planetary exploration where such systems could be needed, and to prepare more advanced RPS technology for possible infusion into future power systems. The 2014-2015 period saw significant changes, and strong progress. Achievements of near-term objectives have enabled definition of a clear path forward in which payoffs from research investments and other sustaining efforts can be applied. The future implementation path is expected to yield a higher-performing thermoelectric generator design, a more isotope-fuel efficient system concept design, and a robust RPS infrastructure maintained effectively within both NASA and the Department of Energy. This paper describes recent work with an eye towards the future plans that result from these achievements.

  9. The NASA Exoplanet Exploration Program

    Science.gov (United States)

    Hudgins, Douglas M.; Blackwood, Gary H.; Gagosian, John S.

    2015-12-01

    The NASA Exoplanet Exploration Program (ExEP) is chartered to implement the NASA space science goals of detecting and characterizing exoplanets and to search for signs of life. The ExEP manages space missions, future studies, technology investments, and ground-based science that either enables future missions or completes mission science. The exoplanet science community is engaged by the Program through Science Definition Teams and through the Exoplanet Program Analysis Group (ExoPAG). The ExEP includes the space science missions of Kepler, K2 , and the proposed WFIRST-AFTA that includes dark energy science, a widefield infrared survey, a microlensing survey for outer-exoplanet demographics, and a coronagraph for direct imaging of cool outer gas- and ice-giants around nearby stars. Studies of probe-scale (medium class) missions for a coronagraph (internal occulter) and starshade (external occulter) explore the trades of cost and science and provide motivation for a technology investment program to enable consideration of missions at the next decadal survey for NASA Astrophysics. Program elements include follow-up observations using the Keck Observatory, which contribute to the science yield of Kepler and K2, and include mid-infrared observations of exo-zodiacal dust by the Large Binocular Telescope Interferometer which provide parameters critical to the design and predicted science yield of the next generation of direct imaging missions. ExEP includes the NASA Exoplanet Science Institute which provides archives, tools, and professional education for the exoplanet community. Each of these program elements contribute to the goal of detecting and characterizing earth-like planets orbiting other stars, and seeks to respond to rapid evolution in this discovery-driven field and to ongoing programmatic challenges through engagement of the scientific and technical communities.

  10. Cells growing in NASA Bioreactor

    Science.gov (United States)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. Shown here, clusters of cells slowly spin inside a bioreactor. On Earth, the cells continually fall through the buffer medium and never hit bottom. In space, they are naturally suspended. Rotation ensures gentle stirring so waste is removed and fresh nutrient and oxygen are supplied. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  11. NASA Electric Propulsion System Studies

    Science.gov (United States)

    Felder, James L.

    2015-01-01

    An overview of NASA efforts in the area of hybrid electric and turboelectric propulsion in large transport. This overview includes a list of reasons why we are looking at transmitting some or all of the propulsive power for the aircraft electrically, a list of the different types of hybrid-turbo electric propulsion systems, and the results of 4 aircraft studies that examined different types of hybrid-turbo electric propulsion systems.

  12. Overview of NASA Ultracapacitor Technology

    Science.gov (United States)

    Hill, Curtis W.

    2017-01-01

    NASA needed a lower mass, reliable, and safe medium for energy storage for ground-based and space applications. Existing industry electrochemical systems are limited in weight, charge rate, energy density, reliability, and safety. We chose a ceramic perovskite material for development, due to its high inherent dielectric properties, long history of use in the capacitor industry, and the safety of a solid state material.

  13. Cells growing in NASA Bioreactor

    Science.gov (United States)

    1998-01-01

    For 5 days on the STS-70 mission, a bioreactor cultivated human colon cancer cells, which grew to 30 times the volume of control specimens grown on Earth. This significant result was reproduced on STS-85 which grew mature structures that more closely match what are found in tumors in humans. Shown here, clusters of cells slowly spin inside a bioreactor. On Earth, the cells continually fall through the buffer medium and never hit bottom. In space, they are naturally suspended. Rotation ensures gentle stirring so waste is removed and fresh nutrient and oxygen are supplied. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  14. Light propagation through anisotropic turbulence.

    Science.gov (United States)

    Toselli, Italo; Agrawal, Brij; Restaino, Sergio

    2011-03-01

    A wealth of experimental data has shown that atmospheric turbulence can be anisotropic; in this case, a Kolmogorov spectrum does not describe well the atmospheric turbulence statistics. In this paper, we show a quantitative analysis of anisotropic turbulence by using a non-Kolmogorov power spectrum with an anisotropic coefficient. The spectrum we use does not include the inner and outer scales, it is valid only inside the inertial subrange, and it has a power-law slope that can be different from a Kolmogorov one. Using this power spectrum, in the weak turbulence condition, we analyze the impact of the power-law variations α on the long-term beam spread and scintillation index for several anisotropic coefficient values ς. We consider only horizontal propagation across the turbulence cells, assuming circular symmetry is maintained on the orthogonal plane to the propagation direction. We conclude that the anisotropic coefficient influences both the long-term beam spread and the scintillation index by the factor ς(2-α).

  15. NASA Strategic Roadmap Summary Report

    Science.gov (United States)

    Wilson, Scott; Bauer, Frank; Stetson, Doug; Robey, Judee; Smith, Eric P.; Capps, Rich; Gould, Dana; Tanner, Mike; Guerra, Lisa; Johnston, Gordon

    2005-01-01

    In response to the Vision, NASA commissioned strategic and capability roadmap teams to develop the pathways for turning the Vision into a reality. The strategic roadmaps were derived from the Vision for Space Exploration and the Aldrich Commission Report dated June 2004. NASA identified 12 strategic areas for roadmapping. The Agency added a thirteenth area on nuclear systems because the topic affects the entire program portfolio. To ensure long-term public visibility and engagement, NASA established a committee for each of the 13 areas. These committees - made up of prominent members of the scientific and aerospace industry communities and senior government personnel - worked under the Federal Advisory Committee Act. A committee was formed for each of the following program areas: 1) Robotic and Human Lunar Exploration; 2) Robotic and Human Exploration of Mars; 3) Solar System Exploration; 4) Search for Earth-Like Planets; 5) Exploration Transportation System; 6) International Space Station; 7) Space Shuttle; 8) Universe Exploration; 9) Earth Science and Applications from Space; 10) Sun-Solar System Connection; 11) Aeronautical Technologies; 12) Education; 13) Nuclear Systems. This document contains roadmap summaries for 10 of these 13 program areas; The International Space Station, Space Shuttle, and Education are excluded. The completed roadmaps for the following committees: Robotic and Human Exploration of Mars; Solar System Exploration; Search for Earth-Like Planets; Universe Exploration; Earth Science and Applications from Space; Sun-Solar System Connection are collected in a separate Strategic Roadmaps volume. This document contains memebership rosters and charters for all 13 committees.

  16. NASA Ames Research Center: An Overview

    Science.gov (United States)

    Tu, Eugene; Yan, Jerry Chi Yiu

    2017-01-01

    This overview of NASA Ames Research Center is intended to give the target audience of university students a general understanding of the mission, core competencies, and research goals of NASA and Ames.

  17. DOE and NASA joint Dark Energy mission

    CERN Multimedia

    2003-01-01

    "DOE and NASA announced their plan for a Joint Dark Energy Mission (JDEM) on October 23, 2003, at the NASA Office of Space Science Structure and Evolution of the Universe Subcommittee (SEUS) meeting" (1 paragraph).

  18. Technology transfer at NASA - A librarian's view

    Science.gov (United States)

    Buchan, Ronald L.

    1991-01-01

    The NASA programs, publications, and services promoting the transfer and utilization of aerospace technology developed by and for NASA are briefly surveyed. Topics addressed include the corporate sources of NASA technical information and its interest for corporate users of information services; the IAA and STAR abstract journals; NASA/RECON, NTIS, and the AIAA Aerospace Database; the RECON Space Commercialization file; the Computer Software Management and Information Center file; company information in the RECON database; and services to small businesses. Also discussed are the NASA publications Tech Briefs and Spinoff, the Industrial Applications Centers, NASA continuing bibliographies on management and patent abstracts (indexed using the NASA Thesaurus), the Index to NASA News Releases and Speeches, and the Aerospace Research Information Network (ARIN).

  19. NASA Technologies that Benefit Society

    Science.gov (United States)

    Griffin, Amanda

    2012-01-01

    Applications developed on Earth of technology needed for space flight have produced thousands of spinoffs that contribute to improving national security, the economy, productivity and lifestyle. Over the course of it s history, NASA has nurtured partnerships with the private sector to facilitate the transfer of NASA-developed technology. For every dollar spent on research and development in the space program, it receives back $7 back in the form of corporate and personal income taxes from increased jobs and economic growth. A new technology, known as Liquid-metal alloy, is the result of a project funded by NASA s Jet Propulsion Lab. The unique technology is a blend of titanium, zirconium, nickel, copper and beryllium that achieves a strength greater than titanium. NASA plans to use this metal in the construction of a drill that will help for the search of water beneath the surface of Mars. Many other applications include opportunities in aerospace, defense, military, automotive, medical instrumentation and sporting goods.Developed in the 1980 s, the original Sun Tigers Inc sunlight-filtering lens has withstood the test of time. This technology was first reported in 1987 by NASA s JPL. Two scientists from JPL were later tasked with studying the harmful effects of radiation produced during laser and welding work. They came up with a transparent welding curtain that absorbs, filters and scatters light to maximize protection of human eyes. The two scientists then began doing business as Eagle Eye Optics. Each pair of sunglasses comes complete with ultraviolet protection, dual layer scratch resistant coating, polarized filters for maximum protection against glare and high visual clarity. Sufficient evidence shows that damage to the eye, especially to the retina, starts much earlier than most people realize. Sun filtering sunglasses are important. Winglets seen at the tips of airplane wings are among aviations most visible fuel-saving, performance enhancing technology

  20. 77 FR 65016 - NASA Federal Advisory Committees

    Science.gov (United States)

    2012-10-24

    ...@hq.nasa.gov Planetary Protection Subcommittee (PPS) _pps-execsec@hq.nasa.gov Planetary Science... weather operational systems. Planetary Protection Subcommittee (PPS)--Planetary Protection Subcommittee is... Protection Officer and other NASA Mission Directorates as required. The scope of the PPS includes...

  1. NASA Ames Environmental Sustainability Report 2011

    Science.gov (United States)

    Clarke, Ann H.

    2011-01-01

    The 2011 Ames Environmental Sustainability Report is the second in a series of reports describing the steps NASA Ames Research Center has taken toward assuring environmental sustainability in NASA Ames programs, projects, and activities. The Report highlights Center contributions toward meeting the Agency-wide goals under the 2011 NASA Strategic Sustainability Performance Program.

  2. NASA Education Implementation Plan 2015-2017

    Science.gov (United States)

    National Aeronautics and Space Administration, 2015

    2015-01-01

    The NASA Education Implementation Plan (NEIP) provides an understanding of the role of NASA in advancing the nation's STEM education and workforce pipeline. The document outlines the roles and responsibilities that NASA Education has in approaching and achieving the agency's and administration's strategic goals in STEM Education. The specific…

  3. 14 CFR 1212.700 - NASA employees.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false NASA employees. 1212.700 Section 1212.700... Authority and Responsibilities § 1212.700 NASA employees. (a) Each NASA employee is responsible for adhering to the requirements of the Privacy Act and this regulation. (b) An employee shall not seek or...

  4. 75 FR 4588 - NASA Advisory Council; Meeting

    Science.gov (United States)

    2010-01-28

    ... SPACE ADMINISTRATION NASA Advisory Council; Meeting AGENCY: National Aeronautics and Space... newly formed Information Technology Infrastructure Committee of the NASA Advisory Council. This will be...-877-613-3958; 2939943. ADDRESSES: NASA Headquarters, 300 E Street, SW., Washington, DC, Room 2N35 FOR...

  5. 78 FR 72719 - NASA Advisory Council; Meeting

    Science.gov (United States)

    2013-12-03

    ... SPACE ADMINISTRATION NASA Advisory Council; Meeting AGENCY: National Aeronautics and Space... NASA Advisory Council (NAC). DATES: Wednesday, December 11, 2013, 1:00 p.m.-5:15 p.m., Local Time; and Thursday, December 12, 2013, 9:00 a.m.-4:00 p.m., Local Time. ADDRESSES: NASA Kennedy Space Center...

  6. 76 FR 41825 - NASA Advisory Council; Meeting

    Science.gov (United States)

    2011-07-15

    ... SPACE ADMINISTRATION NASA Advisory Council; Meeting AGENCY: National Aeronautics and Space... NASA Advisory Council (NAC). The agenda topics for the meeting will include: DATES: Thursday, August 4, 2011, 8 a.m.-5 p.m., and Friday, August 5, 2011, 8 a.m.-12 p.m., Local Time. ADDRESSES: NASA Ames...

  7. 48 CFR 1842.271 - NASA clause.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true NASA clause. 1842.271 Section 1842.271 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... NASA clause. Insert the clause at 1852.242-70, Technical Direction, when paragraph 3(m) of the NASA...

  8. 75 FR 4875 - NASA Advisory Council; Meeting

    Science.gov (United States)

    2010-01-29

    ... SPACE ADMINISTRATION NASA Advisory Council; Meeting AGENCY: National Aeronautics and Space... newly formed Education and Public Outreach Committee of the NASA Advisory Council. This will be the first meeting of this Committee. DATES: February 17, 2010--10 a.m.-4 p.m. (EST). ADDRESSES: NASA...

  9. 75 FR 39973 - NASA Advisory Council; Meeting

    Science.gov (United States)

    2010-07-13

    ... SPACE ADMINISTRATION NASA Advisory Council; Meeting AGENCY: National Aeronautics and Space... NASA Advisory Council. DATES: Thursday, August 5, 2010, 8 a.m.-5 p.m. (local time) Friday, August 6, 2010, 8 a.m.-12 a.m. (local time). ADDRESSES: NASA Jet Propulsion Laboratory, Von Karman Auditorium...

  10. The Lover with a Long Neck: The Motif of Leda and the Swan in Twentieth-Century Slovenian Painting

    Directory of Open Access Journals (Sweden)

    Dejan Prša

    2011-07-01

    Full Text Available This article presents the thesis that the motif of Leda and the Swan, which had a remarkable impact on the arts in the modern era (especially in the period between the Renaissance and the end of the twentieth century, represents one of the most significant Ancient motifs in twentieth-century Slovenian painting. Comparing works of fine arts with European models, comparative research on Slovenian artists’ works, and motif analysis disclose reasons for its popularity in Slovenian ethnic territory and reveal both the stereotyped and original content and the messages incorporated into the motif. Not only have some of the most eminent figures in Slovenian painting (e.g., Jožef Tominc, Anton Ažbe, France Kralj, Stojan Batič, Metka Krašovec, Rudi Španzel, and Marko Jakše dedicated themselves to the motif, but the creations of numerous lesser-known artists (e.g., Samo Kralj, Jože Meglič, and Marina Bahovec have also been particularly influenced by the motif of Leda and the Swan.

  11. Relationship between sunshine duration and temperature trends across Europe since the second half of the twentieth century

    Science.gov (United States)

    Besselaar, E. J. M.; Sanchez-Lorenzo, A.; Wild, M.; Klein Tank, A. M. G.; Laat, A. T. J.

    2015-10-01

    Global radiation is a fundamental source of energy in the climate system. A significant impact of global radiation on temperature change is expected due to the widespread dimming/brightening phenomenon observed since the second half of the twentieth century. This work describes the analysis of 312 stations with sunshine duration (SD) series, a proxy for global radiation, and temperature series in the European Climate Assessment & Dataset (ECA&D) with data over the period 1961-2010. The relationship between SD and temperature series is analyzed for four temperature variables: maximum (Tmax), minimum (Tmin), mean temperature (Tmean), and diurnal temperature range (DTR). The analyses are performed on annual and seasonal basis. The results show strong positive correlations between SD and temperatures over Europe, with highest correlation for DTR and Tmax during the summer period. These results confirm the strong relationship between SD and temperature trends over Europe since the second half of the twentieth century. This study supports previous suggestions that dimming (brightening) has partially decreased (increased) temperatures thereby modulating the greenhouse gas induced warming rates over Europe.

  12. An assemblage of science and home. The gendered lifestyle of Svante Arrhenius and early twentieth-century physical chemistry.

    Science.gov (United States)

    Bergwik, Staffan

    2014-06-01

    This essay explores the gendered lifestyle of early twentieth-century physics and chemistry and shows how that way of life was produced through linking science and home. In 1905, the Swedish physical chemist Svante Arrhenius married Maja Johansson and established a scientific household at the Nobel Institute for Physical Chemistry in Stockholm. He created a productive context for research in which ideas about marriage and family were pivotal. He also socialized in similar scientific sites abroad. This essay displays how scholars in the international community circulated the gendered lifestyle through frequent travel and by reproducing gendered behavior. Everywhere, husbands and wives were expected to perform distinct duties. Shared performances created loyalties across national divides. The essay thus situates the physical sciences at the turn of the twentieth century in a bourgeois gender ideology. Moreover, it argues that the gendered lifestyle was not external to knowledge making but, rather, foundational to laboratory life. A legitimate and culturally intelligible lifestyle produced the trust and support needed for collaboration. In addition, it enabled access to prestigious facilities for Svante Arrhenius, ultimately securing his position in international physical chemistry.

  13. Anomalous mid-twentieth century atmospheric circulation change over the South Atlantic compared to the last 6000 years

    Science.gov (United States)

    Turney, Chris S. M.; Jones, Richard T.; Lister, David; Jones, Phil; Williams, Alan N.; Hogg, Alan; Thomas, Zoë A.; Compo, Gilbert P.; Yin, Xungang; Fogwill, Christopher J.; Palmer, Jonathan; Colwell, Steve; Allan, Rob; Visbeck, Martin

    2016-06-01

    Determining the timing and impact of anthropogenic climate change in data-sparse regions is a considerable challenge. Arguably, nowhere is this more difficult than the Antarctic Peninsula and the subantarctic South Atlantic where observational records are relatively short but where high rates of warming have been experienced since records began. Here we interrogate recently developed monthly-resolved observational datasets from the Falkland Islands and South Georgia, and extend the records back using climate-sensitive peat growth over the past 6000 years. Investigating the subantarctic climate data with ERA-Interim and Twentieth Century Reanalysis, we find that a stepped increase in precipitation across the 1940s is related to a change in synoptic atmospheric circulation: a westward migration of quasi-permanent positive pressure anomalies in the South Atlantic has brought the subantarctic islands under the increased influence of meridional airflow associated with the Amundsen Sea Low. Analysis of three comprehensively multi-dated (using 14C and 137Cs) peat sequences across the two islands demonstrates unprecedented growth rates since the mid-twentieth century relative to the last 6000 years. Comparison to observational and reconstructed sea surface temperatures suggests this change is linked to a warming tropical Pacific Ocean. Our results imply ‘modern’ South Atlantic atmospheric circulation has not been under this configuration for millennia.

  14. Has psychology "found its true path"? Methods, objectivity, and cries of "crisis" in early twentieth-century French psychology.

    Science.gov (United States)

    Carson, John

    2012-06-01

    This article explores how French psychologists understood the state of their field during the first quarter of the twentieth century, and whether they thought it was in crisis. The article begins with the Russian-born psychologist Nicolas Kostyleff and his announcement in 1911 that experimental psychology was facing a crisis. After briefly situating Kostyleff, the article examines his analysis of the troubles facing experimental psychology and his proposed solution, as well as the rather muted response his diagnosis received from the French psychological community. The optimism about the field evident in many of the accounts surveying French psychology during the early twentieth century notwithstanding, a few others did join Kostyleff in declaring that all was not well with experimental psychology. Together their pronouncements suggest that under the surface, important unresolved issues faced the French psychological community. Two are singled out: What was the proper methodology for psychology as a positive science? And what kinds of practices could claim to be objective, and in what sense? The article concludes by examining what these anxieties reveal about the type of science that French psychologists hoped to pursue. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. A Comparative Study: Self-Realization in Twentieth-Century Western Thought, Ibn e Arabi's Idea, and Theatre of The Absurd

    Directory of Open Access Journals (Sweden)

    Bahee Hadaegh

    2011-01-01

    Full Text Available Following humans' struggles to achieve a better under¬standing of the self throughout major historical periods, the idea of the quest for a whole self is once more rekindled in the anxiety-laden atmosphere of the twentieth century. However, unlike the previous approaches, the twentieth century reflection of the notion of the quest for self-realization is paradoxically revealed in a new model of struggle which inclines more toward spiritual search. This inward struggle manifests itself through connecting the ego to the unconscious world, in line with the theories of Freud and Jung. The similarity which exists between Jung's psychic state and the Sufis' mystical world defined by Ibn e Arabi, makes it possible to reconsider the seemingly nihilist readings of the quest for self-realization of the twentieth century absurd thoughts in a positive way

  16. Benchmark Data for Evaluation of Aeroacoustic Propagation Codes With Grazing Flow

    Science.gov (United States)

    Jones, Michael G.; Watson, Willie R.; Parrott, Tony L.

    2005-01-01

    Increased understanding of the effects of acoustic treatment on the propagation of sound through commercial aircraft engine nacelles is a requirement for more efficient liner design. To this end, one of NASA s goals is to further the development of duct propagation and impedance reduction codes. A number of these codes have been developed over the last three decades. These codes are typically divided into two categories: (1) codes that use the measured complex acoustic pressure field to reduce the acoustic impedance of treatment that is positioned along the wall of the duct, and (2) codes that use the acoustic impedance of the treatment as input and compute the sound field throughout the duct. Clearly, the value of these codes is dependent upon the quality of the data used for their validation. Over the past two decades, data acquired in the NASA Langley Research Center Grazing Incidence Tube have been used by a number of researchers for comparison with their propagation codes. Many of these comparisons have been based upon Grazing Incidence Tube tests that were conducted to study specific liner technology components, and were incomplete for general propagation code validation. Thus, the objective of the current investigation is to provide a quality data set that can be used as a benchmark for evaluation of duct propagation and impedance reduction codes. In order to achieve this objective, two parallel efforts have been undertaken. The first of these is the development of an enhanced impedance eduction code that uses data acquired in the Grazing Incidence Tube. This enhancement is intended to place the benchmark data on as firm a foundation as possible. The second key effort is the acquisition of a comprehensive set of data selected to allow propagation code evaluations over a range of test conditions.

  17. Propagation engineering in radio links design

    CERN Document Server

    Ghasemi, Abdollah; Ghasemi, Farshid

    2013-01-01

    Propagation Engineering in Radio Link Design covers the basic principles of radiowaves propagation in a practical manner.  This fundamental understanding enables the readers to design radio links efficiently. This book elaborates on new achievements as well as recently developed propagation models.  This is in addition to a comprehensive overview of fundamentals of propagation in various scenarios. It examines theoretical calculations, approaches and applied procedures needed for radio links design. The authors study and analysis of the main propagation phenomena and its mechanisms based on the recommendations of International Telecommunications Union, (ITU). The book has been organized in 9 chapters and examines the role of antennas and passive reflectors in radio services, propagation mechanisms related to radar, satellite, short distance, broadcasting and trans-horizon radio links, with two chapters devoted to radio noise and main  parameters of radio link design. The book presents some 278 illustration...

  18. A Causal Alternative to Feynman's Propagator

    CERN Document Server

    Koksma, Jurjen F

    2010-01-01

    The Feynman propagator used in the conventional in-out formalism in quantum field theory is not a causal propagator as wave packets are propagated virtually instantaneously outside the causal region of the initial state. We formulate a causal in-out formalism in quantum field theory by making use of the Wheeler propagator, the time ordered commutator propagator, which is manifestly causal. Only free scalar field theories and their first quantization are considered. We identify the real Klein Gordon field itself as the wave function of a neutral spinless relativistic particle. Furthermore, we derive a probability density for our relativistic wave packet using the inner product between states that live on a suitably defined Hilbert space of real quantum fields. We show that the time evolution of our probability density is governed by the Wheeler propagator, such that it behaves causally too.

  19. NASA Alternative Orion Small Cell Battery Design Support

    Science.gov (United States)

    Haynes, Chuck

    2016-01-01

    The NASA Orion Crew Module Reference Design was produced to address large scale thermal runaway (TR) hazard with specific safety controls for the Orion Spacecraft. The design presented provides the description of a full scale battery design reference for implementation as a drop in replacement to meet all spacecraft energy requirements with compatible 120 Vdc electrical and mechanical interface using small cell technology (18650) packaging. The 32V SuperBrick incorporates unique support features and an electrical bus bar arrangement that allows cells negative can insertion into heat sink that is compressively coupled to the battery enclosure to promote good thermal management. The housing design also provides an internal flame suppression "filter tray" and positive venting path internal to the enclosure to allow hot effluent ejecta to escape in the event of single cell TR. Virtual cells (14P Banks) that are supported to provide cell spacing with interstitial materials to prevent side can failures that can produce cell to cell TR propagation. These features were successfully test in four separate TR run with the full scale DTA1 test article in February 2016. Successfully Completed Test Objectives - Four separate TR test runs with Full-Scale DTA1 housing with Two SuperBricks, Two SuperBrick Emulators All Tests resulted in "clean" gas with less than 6 C rise at Battery vent All Tests resulted in less than 2 C temperature rise on cold-plate outlet All Tests resulted in less than 6 psi pressure rise in the battery housing Test Run 1 -One neighbor cell TR, highest remaining neighbor 139 C. Ejecta shorted to bus caused prolonged additional heating, One shorted cell did experience TR after 12 minutes, remaining cells had adequate thermal margin Test Run 2 - No cell to cell propagation, highest neighbor cell 112 C; Test Run 3 - No cell to cell propagation, highest neighbor cell 96 C; Test Run 4 - No cell to cell propagation, highest neighbor cell 101 C; Primary TR testing

  20. Preliminary Statistics from the NASA Alphasat Beacon Receiver in Milan, Italy

    Science.gov (United States)

    Nessel, James; Zemba, Michael; Morse, Jacquelynne; Luini, Lorenzo; Riva, Carlo

    2015-01-01

    NASA Glenn Research Center (GRC) and the Politecnico di Milano (POLIMI) have initiated a joint propagation campaign within the framework of the Alphasat propagation experiment to characterize rain attenuation, scintillation, and gaseous absorption effects of the atmosphere in the 40 gigahertz band. NASA GRC has developed and installed a K/Q-band (20/40 gigahertz) beacon receiver at the POLIMI campus in Milan, Italy, which receives the 20/40 gigahertz signals broadcast from the Alphasat Aldo Paraboni TDP no. 5 beacon payload. The primary goal of these measurements is to develop a physical model to improve predictions of communications systems performance within the Q-band. Herein, we provide an overview of the design and data calibration procedure, and present 6 months of preliminary statistics of the NASA propagation terminal, which has been installed and operating in Milan since May 2014. The Q-band receiver has demonstrated a dynamic range of 40 decibels at an 8-hertz sampling rate. A weather station with an optical disdrometer is also installed to characterize rain drop size distribution for correlation with physical based models.