Science.gov

Sample records for address outstanding nonlinear

  1. A novel DDS using nonlinear ROM addressing with improved compression ratio and quantization noise.

    PubMed

    Chimakurthy, Lakshmi S Jyothi; Ghosh, Malinky; Dai, Fa Foster; Jaeger, Richard C

    2006-02-01

    This paper presents a novel direct digital frequency synthesis (DDFS) ROM compression technique based on two properties of a sine function: (a) piecewise linear technique to approximate a sinusoid, and (b) variation in the slope of the sinusoid at different phase angles. In the proposed DDFS architecture the ROM stores a few of the sinusoidal values, and the interpolation points between the successive stored values are calculated using linear and nonlinear addressing schemes. The nonlinear addressing scheme is used to adaptively vary the number of interpolation points as the slope of the sinusoid changes, leading to a greatly reduced ROM size. The proposed architecture achieves a high compression ratio with a spurious response comparable to that of recent ROM compression techniques. To validate the proposed DDS architecture, the linear, nonlinear, and conventional DDS ROM architectures were implemented in a Xilinx Spartan II FPGA and their spurious performances were compared.

  2. Best Practices & Outstanding Initiatives

    ERIC Educational Resources Information Center

    Training, 2011

    2011-01-01

    In this article, "Training" editors recognize innovative and successful learning and development programs and practices. They share best practices from Automatic Data Processing, Inc., Farmers Insurance Group, FedEx Express, InterContinental Hotels Group, and Oakwood Temporary Housing. They also present the outstanding initiatives of EMD Serono,…

  3. Outstanding laser damage threshold in Li2MnGeS4 and tunable optical nonlinearity in diamond-like semiconductors.

    PubMed

    Brant, Jacilynn A; Clark, Daniel J; Kim, Yong Soo; Jang, Joon I; Weiland, Ashley; Aitken, Jennifer A

    2015-03-16

    The new Li2MnGeS4 and Li2CoSnS4 compounds result from employing a rational and simple design strategy that guides the discovery of diamond-like semiconductors (DLSs) with wide regions of optical transparency, high laser damage threshold, and efficient second-order optical nonlinearity. Single-crystal X-ray diffraction was used to solve and refine the crystal structures of Li2MnGeS4 and Li2CoSnS4, which crystallize in the noncentrosymmetric space groups Pna21 and Pn, respectively. Synchrotron X-ray powder diffraction (SXRPD) was used to assess the phase purity, and diffuse reflectance UV-vis-NIR spectroscopy was used to estimate the bandgaps of Li2MnGeS4 (Eg = 3.069(3) eV) and Li2CoSnS4 (Eg = 2.421(3) eV). In comparison with Li2FeGeS4, Li2FeSnS4, and Li2CoSnS4 DLSs, Li2MnGeS4 exhibits the widest region of optical transparency (0.60-25 μm) and phase matchability (≥1.6 μm). All four of the DLSs exhibit second-harmonic generation and are compared with the benchmark NLO material, AgGaSe2. Most remarkably, Li2MnGeS4 does not undergo two- or three-photon absorption upon exposure to a fundamental Nd:YAG beam (λ = 1.064 μm) and exhibits a laser damage threshold > 16 GW/cm(2).

  4. Outstanding student paper awards

    NASA Astrophysics Data System (ADS)

    The Hydrology Section presented six outstanding student paper awards at the 2000 AGU Spring Meeting in Washington, D.C., last June.Wade T. Crow presented a poster titled Impacts of Upscaling Soil Moisture During SGP 97. He received a B.A. in physics from Carleton College in 1995, and a M.S.E.in civil and environmental engineering from Princeton University in 1998. Wade is currently completing his Ph.D. at Princeton. His dissertation work, supervised by Eric F Wood, focuses on spatial scale issues surrounding both the retrieval of soil moisture imagery by microwave remote sensors and the eventual assimilation of this imagery into hydrologic models.

  5. Outstanding student paper awards

    NASA Astrophysics Data System (ADS)

    Six Outstanding Student Paper awards were given in the Space Physics and Aeronomy Section at the AGU Spring Meeting, held last May in Baltimore, Md.David Walthour, who presented “Satellite Data Analysis of Two-Dimensional Magnetopause Structures,” is a doctoral student at the Thayer School of Engineering, Dartmouth College. He received a B.S. in electrical engineering from the University of Cincinnati. His research interests include field-aligned MHD flows, the development of data analysis techniques for examining transient events at the Earth magnetopause, and the study of anomalous MHD wave properties in anisotropic plasmas with application to reconnection.

  6. Outstanding student papers

    NASA Astrophysics Data System (ADS)

    Two presentations were named Outstanding Student Papers in the Geodesy Section at the 1993 AGU Fall Meeting in San Francisco, Calif.Susan Owen was honored for her presentation “1990-1993 Surface Displacements on Kilauea Volcano Determined by GPS.” She is a Ph.D. student in the Geophysics department at Stanford University, Palo Alto, Calif. She received a B.A. in Physics from Harvard-Radcliffe College. Owen's research involves working with GPS data from Kilauea Volcano. She is also interested in active tectonic, crustal deformation, and the earthquake process.

  7. Outstanding Nonfiction Choices for 1998.

    ERIC Educational Resources Information Center

    Aoki, Elaine; Jensen, Julie; Kerper, Richard; Nathan, Ruth; Smith, Karen Patricia; Zarnowski, Myra

    2000-01-01

    Offers brief descriptions of 20 outstanding nonfiction for children, including the 1999 Orbis Pictus Award winner, and four Orbis Pictus honor books as well as a number of other outstanding nonfiction titles dealing mainly with history and biography. (SR)

  8. Outstanding student papers

    NASA Astrophysics Data System (ADS)

    Eight presentations were named Outstanding Student Papers in the Atmospheric Sciences Section at the 1995 Fall Meeting.Steve Davis, who presented “Reversal Effects in Wideband dE/dt from Lightning Measured at Multiple Ground Stations,” is currently attending the University of Florida pursuing a Ph.D. in electrical engineering. He graduated with high honors in 1990 with his bachelor's degree in electrical engineering from the University of Florida. He received his master's degree in 1992 from the University of Florida. The research for his master's degree was in the area of photonics with applications to laser and waveguide structures. His current research with Ewen Thomson involves measuring radiation from lightning at multiple ground stations. From these measurements, he hopes to determine lightning parameters such as velocities and currents and apply these to new and existing models.

  9. Outstanding student paper awards

    NASA Astrophysics Data System (ADS)

    The Hydrology Section presented five outstanding student paper awards at the 1999 Spring Meeting in Boston, Massachusetts, last June.Maneesha Joshi presented a poster titled “Estimation of the Extent and Duration of Melt on the Greenland Ice Sheet using an Edge Detection Technique on Passive Microwave Data.” She received her B.Tech. in civil engineering from the Indian Institute of Technology, Bombay in 1991, and a M.S. in environmental engineering from State University of New York, Buffalo in 1994. Maneesha expects to complete her Ph.D. in civil engineering (remote sensing) in September 1999, under the supervision of Carolyn Merry (Department of Civil and Environmental Engineering & Geodetic Science), Ken Jezek, and John Bolzan (Byrd Polar Research Center) at the Ohio State University, Columbus, Ohio. Her thesis focuses on estimating the extent of melt, melt season, and duration, and absorbed radiation on the Greenland ice sheet from passive microwave and SAR data. Maneesha's other interests include image processing, issues related to global climate change, and photogrammetry.

  10. Outstanding student paper awards

    NASA Astrophysics Data System (ADS)

    The Atmospheric Sciences Section presented the following outstanding student paper awards at the AGU 1997 Fall Meeting in San Francisco, California, last December. James Corbett presented a poster on “Nitrogen and Sulfur Emissions From Oceangoing Ships.” James is a Ph.D. candidate in the Department of Engineering and Public Policy (EPP) at Carnegie Mellon University, Pittsburgh, Pa. He has been awarded a M.S. degree in EPP and recently completed the M.S. requirements in the Department of Mechanical Engineering. He graduated in 1985 with a degree in marine engineering technology from the California Maritime Academy and holds a California Professional Engineering License (Mechanical). He joined the doctoral program in engineering and public policy at Carnegie Mellon University in August 1995. In 1997, he was selected for a U.S. EPA STAR Fellowship. His research focuses on international maritime transportation and pollution issues, particularly air emissions from ship propulsion. James has developed the first global geographic characterization of air emissions from international maritime transport. As recently published in Science (Corbett and Fischbeck, 1997), his work estimates the global annual nitrogen and sulfur emissions from ships to be 3.08 terragrams (Tg) N and 4.24 Tg S, respectively.

  11. Outstanding student paper award

    NASA Astrophysics Data System (ADS)

    The Planetology Section presented an outstanding student paper award to Julie Ann Rathbun at the AGU 1998 Spring Meeting in Boston, Mass., last May. Julie Ann Rathbun presented a paper titled “Ice Diapirs on Europa and Their Implications."” Julie received her B.S. degree in physics from the State University of New York at Buffalo in May 1994. She has an M.S. in astronomy from Cornell University that she received in July 1997. At present, she is working towards a Ph.D. in astronomy from Cornell under the direction of Steven Squyres. Julie's thesis topic is studying thermal upwellings on Venus and Europa using techniques developed for Coronae formation. She is doing this study in order to understand the subsurface structure of the bodies and how similar processes can differ in icy and rocky bodies. Work already accomplished toward this thesis are Magellan data used to model the formation of Beta Regio and Theia Mons, and Galileo data used to model the formation of small topographic domes to show that a liquid water ocean must have been present at the time of their formation.

  12. Outstanding student papers

    NASA Astrophysics Data System (ADS)

    Two presentations in the Geodesy Section were named Outstanding Student Papers at AGU's Spring Meeting in Baltimore, Md.John Weber presented “Estimation of Site Velocity Gradients from GPS Measurements in the New Madrid Seismic Zone.” Weber received an A.S. (1980) from Moraine Valley Community College, then a B.S. (1982), and an M.S(1987), both in Geology, from Southern Illinois University-Carbondale. He completed his Ph.D. (1995) research at Northwestern University as a NASA Fellow, and is currently working at RSMAS as an NSF Postdoctoral Fellow. In his work, he estimates strains and motions in the Caribbean-South America plate boundary zone by comparing historic (1901) triangulation data to 1994 GPS measurements. His research interests are broadly related to kinematics and deformation, mostly in plate boundary zones (ancient and modern), although his Ph.D. research focused on poorly understood intraplate deformation. He applies in his research techniques from both geodesy and structural geology. This fall, he will start a new position as a structural geologist at Grand Valley State University, Michigan.

  13. Addressing the unemployment-mortality conundrum: non-linearity is the answer.

    PubMed

    Bonamore, Giorgio; Carmignani, Fabrizio; Colombo, Emilio

    2015-02-01

    The effect of unemployment on mortality is the object of a lively literature. However, this literature is characterized by sharply conflicting results. We revisit this issue and suggest that the relationship might be non-linear. We use data for 265 territorial units (regions) within 23 European countries over the period 2000-2012 to estimate a multivariate regression of mortality. The estimating equation allows for a quadratic relationship between unemployment and mortality. We control for various other determinants of mortality at regional and national level and we include region-specific and time-specific fixed effects. The model is also extended to account for the dynamic adjustment of mortality and possible lagged effects of unemployment. We find that the relationship between mortality and unemployment is U shaped. In the benchmark regression, when the unemployment rate is low, at 3%, an increase by one percentage point decreases average mortality by 0.7%. As unemployment increases, the effect decays: when the unemployment rate is 8% (sample average) a further increase by one percentage point decreases average mortality by 0.4%. The effect changes sign, turning from negative to positive, when unemployment is around 17%. When the unemployment rate is 25%, a further increase by one percentage point raises average mortality by 0.4%. Results hold for different causes of death and across different specifications of the estimating equation. We argue that the non-linearity arises because the level of unemployment affects the psychological and behavioural response of individuals to worsening economic conditions.

  14. Outstanding Nonfiction Choices for 2000.

    ERIC Educational Resources Information Center

    Kerper, Richard M., Ed.; Duthie, Christine; Jensen, Julie M.; Lott, Carolyn; Nathan, Ruth; Smith, Karen Patricia; Zarnowski, Myra

    2001-01-01

    Features 20 outstanding books published in 2000 and selected by the 2001 Orbis Pictus Award Committee. Presents books focusing on trailblazers, exhibiting outstanding human achievement; views from the artistic world; views from the scientific world; and views from the historic world. (SG)

  15. What Makes an Outstanding PTA?

    ERIC Educational Resources Information Center

    Kuersten, Joan

    1998-01-01

    One outstanding PTA created effective communication between school and home in order to facilitate the transition from a traditional school calendar to year-round school. The Home-School Communication Project provides information via a communication folder for families of in-school children; a newsletter for all families; and a PTA telephone…

  16. Archetypes of Outstanding Female Superintendents.

    ERIC Educational Resources Information Center

    Funk, Carole; Pankake, Anita; Schroth, Gwen

    This report documents a study of women superintendents. Specifically, the study identified professional and personal characteristics and styles of leadership to develop archetypes of six outstanding female superintendents in Texas. The intent of the research was also to reveal similarities between and among these superintendents that could provide…

  17. Outstanding Translated Children's Books: Birth of a Bibliography by Committee.

    ERIC Educational Resources Information Center

    Beitler, Roslyn; Bush, Margaret; Gebel, Doris; Mavrogenes, Sylvia; Pelan, Louise; Peterman, Hedra; Smuda, Janice; Sommer, Judith; Trevino, Rose; White, Maureen

    1998-01-01

    In addition to providing an annotated bibliography and a set of criteria for selecting outstanding translated children's books, this article addresses the collaborative process by the International Relations Committee (IRC) of the Association for Library Service to Children (ALSC) of producing such a bibliography. Sources include…

  18. Outstanding problems in Mars aeronomy

    NASA Technical Reports Server (NTRS)

    Luhmann, J. G.

    1995-01-01

    Although the Phobos-2 spacecraft recently obtained important results relevant to some of the major remaining questions in Mars aeronomy, much remains to be done. In particular, not since the Viking Landers have we made in-situ measurements of aeronomical quantities such as atmospheric and ionospheric densities and temperatures below 400 km altitude. We have never made magnetic field measurements at these altitudes. Without such measurements we cannot unambiguously resolve arguments concerning issues such as the significance of the planetary magnetic field in the solar wind interaction, or understand the atmospheric cycle that leads to escape to space. With the trio of future orbiters including Mars Observer, Mars-94, and Planet-B we should see a veritable explosion of new knowledge, but some gaps in aeronomical science coverage will still remain. This paper briefly reviews some of the major unsolved problems in Mars aeronomy, and points out which are expected to remain outstanding after this flotilla of missions.

  19. The Outstanding Investigator Award (R35)

    Cancer.gov

    NCI established the Outstanding Investigator Award (R35) in 2015, for principal investigators who have achieved significant research accomplishments. This video features one of the first group of 62 researchers to receive the award.

  20. Outstanding Nonfiction Choices for 1993 (Bookalogues).

    ERIC Educational Resources Information Center

    Aoki, Elaine; And Others

    1994-01-01

    Features the 14 outstanding nonfiction titles published in 1993 and selected by the 1994 Orbis Pictus Award Committee. Presents annotations of the award and honor books, books for all ages, and books for intermediate grades and above. (RS)

  1. A Portfolio of Outstanding Contemporary American Indians.

    ERIC Educational Resources Information Center

    Wood, Theodore E. B.

    The portfolio contains 24 portraits with biographical sketches of outstanding contemporary American Indians. Representing several tribes, occupations, and points of view, the subjects are: Henry Adams, Louis W. Ballard, Robert L. Bennett, George Blue Spruce, Jarrett Blythe, Louis R. Bruce, Leon Cook, Ada Deer, Vine Deloria, Jr., James Gladstone,…

  2. Glimpses into Northwest Lives: Some Outstanding Women.

    ERIC Educational Resources Information Center

    Simon-McWilliams, Ethel; Caldwell, Fran

    Intended as a motivational tool to be used in public school classroom instruction and counseling, this document recognizes some of the outstanding women, from varied ethnic and racial backgrounds, who have contributed to life in the northwestern United States. The document contains succinct biographies of 37 women, and also includes suggestions to…

  3. Favorite Labs from Outstanding Teachers. Volume II.

    ERIC Educational Resources Information Center

    Sanders, Linda R., Ed.

    One of the most valuable resources for obtaining exemplary instructional materials for the classroom is teachers. This booklet contains numerous laboratory activities compiled from submissions by recipients of the National Association of Biology Teachers' Outstanding Biology Teacher Award (1989-92). Topics are sorted into the following sections:…

  4. Leveraging Information Technology. Track VII: Outstanding Applications.

    ERIC Educational Resources Information Center

    CAUSE, Boulder, CO.

    Eight papers from the 1987 CAUSE conference's Track VII, Outstanding Applications, are presented. They include: "Image Databases in the University" (Reid Kaplan and Gordon Mathieson); "Using Information Technology for Travel Management at the University of Michigan" (Robert E. Russell and John C. Hufziger); "On-Line Access…

  5. Identification and Support of Outstanding Astronomy Students

    NASA Astrophysics Data System (ADS)

    Stoev, A. D.; Bozhurova, E. S.

    2006-08-01

    The aims, organizational plan and syllabus of a specialized Astronomy School with a subject of training students for participation in the International Astronomy Olympiad, are presented. Thematic frame includes basic educational activities during the preparation and self-preparation of the students and their participation in astronomical Olympiads. A model of identification and selection of outstanding students for astronomical Olympiads has been developed. Examples of didactic systems of problems for development of mathematical, physical and astronomical skills are shown. The programme ends with individual training for solving problems on astronomy and astrophysics. Possibilities, which the characteristic, non-standard astronomical problems give for stimulating the creative and original thinking, are specified. Basic psychological condition for development of the students' creative potential - transformation of the cognitive content in emotional one - is demonstrated. The programme of identification and support of outstanding students on astronomy is realized in collaboration with The Ministry of Education and Science, Public Astronomical Observatories and Planetaria, Institute of Astronomy - Bulgarian Academy of Sciences, and The Union of Astronomers in Bulgaria.

  6. 11 CFR 9034.5 - Net outstanding campaign obligations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 11 Federal Elections 1 2013-01-01 2012-01-01 true Net outstanding campaign obligations. 9034.5...: PRESIDENTIAL PRIMARY MATCHING FUND ENTITLEMENTS § 9034.5 Net outstanding campaign obligations. (a) Within 15... shall submit a statement of net outstanding campaign obligations. The candidate's net...

  7. 11 CFR 9034.5 - Net outstanding campaign obligations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 11 Federal Elections 1 2011-01-01 2011-01-01 false Net outstanding campaign obligations. 9034.5...: PRESIDENTIAL PRIMARY MATCHING FUND ENTITLEMENTS § 9034.5 Net outstanding campaign obligations. (a) Within 15... shall submit a statement of net outstanding campaign obligations. The candidate's net...

  8. 11 CFR 9034.5 - Net outstanding campaign obligations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 11 Federal Elections 1 2012-01-01 2012-01-01 false Net outstanding campaign obligations. 9034.5...: PRESIDENTIAL PRIMARY MATCHING FUND ENTITLEMENTS § 9034.5 Net outstanding campaign obligations. (a) Within 15... shall submit a statement of net outstanding campaign obligations. The candidate's net...

  9. 11 CFR 9034.5 - Net outstanding campaign obligations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 11 Federal Elections 1 2014-01-01 2014-01-01 false Net outstanding campaign obligations. 9034.5...: PRESIDENTIAL PRIMARY MATCHING FUND ENTITLEMENTS § 9034.5 Net outstanding campaign obligations. (a) Within 15... shall submit a statement of net outstanding campaign obligations. The candidate's net...

  10. MacCready awarded Outstanding Student Paper

    NASA Astrophysics Data System (ADS)

    Parker MacCready was selected by the Ocean Sciences Section to receive their Outstanding Student Paper Award from the 1989 Fall Meeting in San Francisco for his paper entitled “Stratified Spin-up Over a Slope.” Following receipt of his Bachelor's degree in architecture from Yale in 1982, MacCready went to China for 5 months to study the language. On his return to Pasadena he worked for 3 years for Aerovironment, Inc., concentrating on building and flying a human-powered aircraft and a giant wing-flapping replica of a pterosaur. Having become interested in the aerodynamics of flappingwing propulsion, he continued his studies at Caltech, where he received his Master's degree in 1986. His informal thesis project was a human-powered hydrofoil boat with flapping-wing propulsion. He is currently working on his doctorate in physical oceanography at the University of Washington, where he is studying the dynamics of stratified, rotating boundary layers over topography. His switch to oceanography was motivated by his feeling that environmental fluid mechanics would become an increasingly relevant subject in light of increasing world pollution. In the future he hopes to go into environmental politics, perhaps in a scientific advisory role.

  11. Terahertz spectroscopy of low-dimensional nanomaterials: nonlinear emission and ultrafast electrodynamics

    NASA Astrophysics Data System (ADS)

    Luo, Liang; Wang, Jigang

    2015-08-01

    Nonlinear and non-equilibrium properties of low-dimensional quantum materials are fundamental in nanoscale science yet transformative in nonlinear imaging/photonic technology today. These have been poorly addressed in many nano-materials despite of their well-established equilibrium optical and transport properties. The development of ultrafast terahertz (THz) sources and nonlinear spectroscopy tools facilitates understanding these issues and reveals a wide range of novel nonlinear and quantum phenomena that are not expected in bulk solids or atoms. In this paper, we discuss our recent discoveries in two model photonic and electronic nanostructures to solve two outstanding questions: (1) how to create nonlinear broadband terahertz emitters using deeply subwavelength nanoscale meta-atom resonators? (2) How to access one-dimensional (1D) dark excitons and their non-equilibrium correlated states in single-walled carbon nanotubes (SWMTs)?

  12. Terahertz Spectroscopy of Low-Dimensional Nanomaterials: Nonlinear Emission and Ultrafast Electrodynamics

    DOE PAGES

    Luo, Liang; Wang, Jigang

    2016-01-01

    Nonlinear and non-equilibrium properties of low-dimensional quantum materials are fundamental in nanoscale science yet transformative in nonlinear imaging/photonic technology today. These have been poorly addressed in many nano-materials despite of their well-established equilibrium optical and transport properties. The development of ultrafast terahertz (THz) sources and nonlinear spectroscopy tools facilitates understanding these issues and reveals a wide range of novel nonlinear and quantum phenomena that are not expected in bulk solids or atoms. In this paper, we discuss our recent discoveries in two model photonic and electronic nanostructures to solve two outstanding questions: (1) how to create nonlinear broadband terahertz emittersmore » using deeply subwavelength nanoscale meta-atom resonators? (2) How to access one-dimensional (1D) dark excitons and their non-equilibrium correlated states in single-walled carbon nanotubes (SWMTs)?« less

  13. Terahertz Spectroscopy of Low-Dimensional Nanomaterials: Nonlinear Emission and Ultrafast Electrodynamics

    SciTech Connect

    Luo, Liang; Wang, Jigang

    2016-01-01

    Nonlinear and non-equilibrium properties of low-dimensional quantum materials are fundamental in nanoscale science yet transformative in nonlinear imaging/photonic technology today. These have been poorly addressed in many nano-materials despite of their well-established equilibrium optical and transport properties. The development of ultrafast terahertz (THz) sources and nonlinear spectroscopy tools facilitates understanding these issues and reveals a wide range of novel nonlinear and quantum phenomena that are not expected in bulk solids or atoms. In this paper, we discuss our recent discoveries in two model photonic and electronic nanostructures to solve two outstanding questions: (1) how to create nonlinear broadband terahertz emitters using deeply subwavelength nanoscale meta-atom resonators? (2) How to access one-dimensional (1D) dark excitons and their non-equilibrium correlated states in single-walled carbon nanotubes (SWMTs)?

  14. Volcanic Eruptions and Climate: Outstanding Research Issues

    NASA Astrophysics Data System (ADS)

    Robock, Alan

    2016-04-01

    Large volcanic eruptions inject sulfur gases into the stratosphere, which convert to sulfate aerosols with an e-folding residence time of about one year. The radiative and chemical effects of this aerosol cloud produce responses in the climate system. Based on observations after major eruptions of the past and experiments with numerical models of the climate system, we understand much about their climatic impact, but there are also a number of unanswered questions. Volcanic eruptions produce global cooling, and are an important natural cause of interannual, interdecadal, and even centennial-scale climate change. One of the most interesting volcanic effects is the "winter warming" of Northern Hemisphere continents following major tropical eruptions. During the winter in the Northern Hemisphere following every large tropical eruption of the past century, surface air temperatures over North America, Europe, and East Asia were warmer than normal, while they were colder over Greenland and the Middle East. This pattern and the coincident atmospheric circulation correspond to the positive phase of the Arctic Oscillation. While this response is observed after recent major eruptions, most state-of-the-art climate models have trouble simulating winter warming. Why? High latitude eruptions in the Northern Hemisphere, while also producing global cooling, do not have the same impact on atmospheric dynamics. Both tropical and high latitude eruptions can weaken the Indian and African summer monsoon, and the effects can be seen in past records of flow in the Nile and Niger Rivers. Since the Mt. Pinatubo eruption in the Philippines in 1991, there have been no large eruptions that affected climate, but the cumulative effects of small eruptions over the past decade have had a small effect on global temperature trends. Some important outstanding research questions include: How much seasonal, annual, and decadal predictability is possible following a large volcanic eruption? Do

  15. Talking about Books: Outstanding Nonfiction Choices for 1997.

    ERIC Educational Resources Information Center

    Aoki, Elaine; Jensen, Julie; Kerper, Richard; Nathan, Ruth; Smith, Karen Patricia; Zarnowski, Myra

    1998-01-01

    Presents descriptions of (1) the 1997 winner of the Orbis Pictus Award for Outstanding Nonfiction for Children ("An Extraordinary Life: The Story of a Monarch Butterfly"); (2) the 5 Orbis Pictus Honor Books; and (3) 12 other outstanding nonfiction titles selected by the award committee, 6 dealing with history and biography and 6 dealing with the…

  16. Talking about Books: Outstanding Nonfiction Choices for 1996.

    ERIC Educational Resources Information Center

    Aoki, Elaine; Jensen, Julie; Kerper, Richard; Nathan, Ruth; Smith, Karen Patricia; Zarnowski, Myra

    1997-01-01

    Presents substantial annotations of outstanding nonfiction books for children published in 1996, including the 1997 Orbis Pictus Award winner and three 1997 Orbis Pictus Honor books. Presents annotations of 14 other outstanding nonfiction titles, grouped in the following categories: understanding the natural world; looking critically at history;…

  17. Talking about Books: Outstanding Nonfiction Choices for 1999.

    ERIC Educational Resources Information Center

    Kerper, Richard M.; Aoki, Elaine; Duthie, Christine; Jensen, Julie; Lott, Carolyn; Nathan, Ruth; Smith, Karen Patricia; Zarnowski, Myra

    2000-01-01

    Presents and discusses the book which won the 2000 Orbis Pictus Award for Outstanding Nonfiction for Children: "Through My Eyes" by Ruby Bridges. Discusses the five Honor books chosen by the award committee, and offers descriptions of 14 other nonfiction books selected as outstanding by the award committee. (SR)

  18. Addressing healthcare.

    PubMed

    Daly, Rich

    2013-02-11

    Though President Barack Obama has rarely made healthcare references in his State of the Union addresses, health policy experts are hoping he changes that strategy this year. "The question is: Will he say anything? You would hope that he would, given that that was the major issue he started his presidency with," says Dr. James Weinstein, left, of the Dartmouth-Hitchcock health system.

  19. The Ten Outstanding Engineering Achievements of the Past 50 Years.

    ERIC Educational Resources Information Center

    Hightower, George

    1984-01-01

    Describes the outstanding achievement in each of 10 major engineering categories. These categories include synthetic fibers, nuclear energy, computers, solid state electronics, jet aircraft, biomedical engineering, lasers, communications satellites, the United States space program, and automation and control systems. (JN)

  20. Outstanding Science Trade Books for Students K-12.

    ERIC Educational Resources Information Center

    Science Teacher, 2003

    2003-01-01

    Presents outstanding science trade books published in 2002 for students in grades K-12. Sections include Archaeology, Anthropology, and Paleontology; Biography; Environment and Ecology; Life Science; Physical Science; and Science-Related Careers. (KHR)

  1. Outstanding Science Trade Books for Children for 1996.

    ERIC Educational Resources Information Center

    Science and Children, 1996

    1996-01-01

    Presents an annotated bibliography of outstanding children's science trade books published in 1995 and intended primarily for kindergarten to eighth grade. Sections include biography, environment and ecology, fiction, life science, medicine and medical research, paleontology, and technology and engineering. (JRH)

  2. Outstanding Science Trade Books for Children for 2000.

    ERIC Educational Resources Information Center

    Science and Children, 2000

    2000-01-01

    Lists outstanding science trade books for children in the categories of Biography, Earth and Space Science, Integrated Science, Life Science, Physical Science, and Technology and Engineering. Explains the book selection process. (YDS)

  3. 11 CFR 9004.9 - Net outstanding qualified campaign expenses.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... difference between 11 CFR 9004.9(a) (1) and (2). (1) The total of: (i) All outstanding obligations for... required by 11 CFR 9004.9(a) (1) and (2), except that the amount of outstanding obligations under 11 CFR 9004.9(a)(1)(i) and the amount of cash on hand, assets and receivables under 11 CFR 9004.9(a)(2)...

  4. 11 CFR 9004.9 - Net outstanding qualified campaign expenses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... difference between 11 CFR 9004.9(a) (1) and (2). (1) The total of: (i) All outstanding obligations for... required by 11 CFR 9004.9(a) (1) and (2), except that the amount of outstanding obligations under 11 CFR 9004.9(a)(1)(i) and the amount of cash on hand, assets and receivables under 11 CFR 9004.9(a)(2)...

  5. 11 CFR 9004.9 - Net outstanding qualified campaign expenses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... difference between 11 CFR 9004.9(a) (1) and (2). (1) The total of: (i) All outstanding obligations for... required by 11 CFR 9004.9(a) (1) and (2), except that the amount of outstanding obligations under 11 CFR 9004.9(a)(1)(i) and the amount of cash on hand, assets and receivables under 11 CFR 9004.9(a)(2)...

  6. 11 CFR 9004.9 - Net outstanding qualified campaign expenses.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... difference between 11 CFR 9004.9(a) (1) and (2). (1) The total of: (i) All outstanding obligations for... required by 11 CFR 9004.9(a) (1) and (2), except that the amount of outstanding obligations under 11 CFR 9004.9(a)(1)(i) and the amount of cash on hand, assets and receivables under 11 CFR 9004.9(a)(2)...

  7. Inaugural address

    NASA Astrophysics Data System (ADS)

    Joshi, P. S.

    2014-03-01

    From jets to cosmos to cosmic censorship P S Joshi Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India E-mail: psj@tifr.res.in 1. Introduction At the outset, I should like to acknowledge that part of the title above, which tries to capture the main flavour of this meeting, and has been borrowed from one of the plenary talks at the conference. When we set out to make the programme for the conference, we thought of beginning with observations on the Universe, but then we certainly wanted to go further and address deeper questions, which were at the very foundations of our inquiry, and understanding on the nature and structure of the Universe. I believe, we succeeded to a good extent, and it is all here for you in the form of these Conference Proceedings, which have been aptly titled as 'Vishwa Mimansa', which could be possibly translated as 'Analysis of the Universe'! It is my great pleasure and privilege to welcome you all to the ICGC-2011 meeting at Goa. The International Conference on Gravitation and Cosmology (ICGC) series of meetings are being organized by the Indian Association for General Relativity and Gravitation (IAGRG), and the first such meeting was planned and conducted in Goa in 1987, with subsequent meetings taking place at a duration of about four years at various locations in India. So, it was thought appropriate to return to Goa to celebrate the 25 years of the ICGC meetings. The recollections from that first meeting have been recorded elsewhere here in these Proceedings. The research and teaching on gravitation and cosmology was initiated quite early in India, by V V Narlikar at the Banares Hindu University, and by N R Sen in Kolkata in the 1930s. In course of time, this activity grew and gained momentum, and in early 1969, at the felicitation held for the 60 years of V V Narlikar at a conference in Ahmedabad, P C Vaidya proposed the formation of the IAGRG society, with V V Narlikar being the first President. This

  8. Convocation address.

    PubMed

    Kakodkar, A

    1999-07-01

    This convocation addressed by Dr. Anil Kakodkar focuses on the challenges faced by graduating students. In his speech, he emphasized the high level of excellence achieved by the industrial sector; however, he noted that there has been a loss of initiative in maximizing value addition, which was worsened by an increasing population pressure. In facing a stiff competition in the external and domestic markets, it is imperative to maximize value addition within the country in a competitive manner and capture the highest possible market share. To achieve this, high-quality human resources are central. Likewise, family planning programs should become more effective and direct available resources toward national advantage. To boost the domestic market, he suggests the need to search for strengths to achieve leadership position in those areas. First, an insight into the relationship between the lifestyles and the needs of our people and the natural resource endowment must be gained. Second, remodeling of the education system must be undertaken to prepare the people for adding the necessary innovative content in our value addition activities. Lastly, Dr. Kakodkar emphasizes the significance of developing a strong bond between parents and children to provide a sound foundation and allow the education system to grow upon it.

  9. Outstanding issues related to thermospheric measurements and modelling

    NASA Astrophysics Data System (ADS)

    Moe, Kenneth; Moe, Mildred M.; Doornbos, Eelco

    Semi-empirical thermospheric models are dependent on measurements made in orbit. Out-standing issues regarding the interpretation of those measurements and the effects on models are considered. These include the present state of knowledge of drag coefficients, long-term trends, instrument calibration, radiation pressure, and spacecraft geometry. Many recent and ongoing efforts to evaluate and improve thermospheric models will be described. The advent of attitude-controlled nanosatellites of simple shapes presents opportunities to resolve some of these outstanding issues in conjunction with the forthcoming SWARM program.

  10. Opening Address

    NASA Astrophysics Data System (ADS)

    Yamada, T.

    2014-12-01

    Ladies and Gentlemen, it is my great honor and pleasure to present an opening address of the 3rd International Workshop on "State of the Art in Nuclear Cluster Physics"(SOTANCP3). On the behalf of the organizing committee, I certainly welcome all your visits to KGU Kannai Media Center belonging to Kanto Gakuin University, and stay in Yokohama. In particular, to whom come from abroad more than 17 countries, I would appreciate your participations after long long trips from your homeland to Yokohama. The first international workshop on "State of the Art in Nuclear Cluster Physics", called SOTANCP, was held in Strasbourg, France, in 2008, and the second one was held in Brussels, Belgium, in 2010. Then the third workshop is now held in Yokohama. In this period, we had the traditional 10th cluster conference in Debrecen, Hungary, in 2012. Thus we have the traditional cluster conference and SOTANCP, one after another, every two years. This obviously shows our field of nuclear cluster physics is very active and flourishing. It is for the first time in about 10 years to hold the international workshop on nuclear cluster physics in Japan, because the last cluster conference held in Japan was in Nara in 2003, about 10 years ago. The president in Nara conference was Prof. K. Ikeda, and the chairpersons were Prof. H. Horiuchi and Prof. I. Tanihata. I think, quite a lot of persons in this room had participated at the Nara conference. Since then, about ten years passed. So, this workshop has profound significance for our Japanese colleagues. The subjects of this workshop are to discuss "the state of the art in nuclear cluster physics" and also discuss the prospect of this field. In a couple of years, we saw significant progresses of this field both in theory and in experiment, which have brought better and new understandings on the clustering aspects in stable and unstable nuclei. I think, the concept of clustering has been more important than ever. This is true also in the

  11. Presidential address.

    PubMed

    Vohra, U

    1993-07-01

    The Secretary of India's Ministry of Health and Family Welfare serves as Chair of the Executive Council of the International Institute for Population Sciences in Bombay. She addressed its 35th convocation in 1993. Global population stands at 5.43 billion and increases by about 90 million people each year. 84 million of these new people are born in developing countries. India contributes 17 million new people annually. The annual population growth rate in India is about 2%. Its population size will probably surpass 1 billion by the 2000. High population growth rates are a leading obstacle to socioeconomic development in developing countries. Governments of many developing countries recognize this problem and have expanded their family planning programs to stabilize population growth. Asian countries that have done so and have completed the fertility transition include China, Japan, Singapore, South Korea, and Thailand. Burma, Malaysia, North Korea, Sri Lanka, and Vietnam have not yet completed the transition. Afghanistan, Bangladesh, Iran, Nepal, and Pakistan are half-way through the transition. High population growth rates put pressure on land by fragmenting finite land resources, increasing the number of landless laborers and unemployment, and by causing considerable rural-urban migration. All these factors bring about social stress and burden civic services. India has reduced its total fertility rate from 5.2 to 3.9 between 1971 and 1991. Some Indian states have already achieved replacement fertility. Considerable disparity in socioeconomic development exists among states and districts. For example, the states of Bihar, Madhya Pradesh, Rajasthan, and Uttar Pradesh have female literacy rates lower than 27%, while that for Kerala is 87%. Overall, infant mortality has fallen from 110 to 80 between 1981 and 1990. In Uttar Pradesh, it has fallen from 150 to 98, while it is at 17 in Kerala. India needs innovative approaches to increase contraceptive prevalence rates

  12. Welcome Address

    NASA Astrophysics Data System (ADS)

    Kiku, H.

    2014-12-01

    Ladies and Gentlemen, It is an honor for me to present my welcome address in the 3rd International Workshop on "State of the Art in Nuclear Cluster Physics"(SOTANCP3), as the president of Kanto Gakuin University. Particularly to those from abroad more than 17 countries, I am very grateful for your participation after long long trips from your home to Yokohama. On the behalf of the Kanto Gakuin University, we certainly welcome your visit to our university and stay in Yokohama. First I would like to introduce Kanto Gakuin University briefly. Kanto Gakuin University, which is called KGU, traces its roots back to the Yokohama Baptist Seminary founded in 1884 in Yamate, Yokohama. The seminary's founder was Albert Arnold Bennett, alumnus of Brown University, who came to Japan from the United States to establish a theological seminary for cultivating and training Japanese missionaries. Now KGU is a major member of the Kanto Gakuin School Corporation, which is composed of two kindergartens, two primary schools, two junior high schools, two senior high schools as well as KGU. In this university, we have eight faculties with graduate school including Humanities, Economics, Law, Sciences and Engineering, Architecture and Environmental Design, Human and Environmental Studies, Nursing, and Law School. Over eleven thousands students are currently learning in our university. By the way, my major is the geotechnical engineering, and I belong to the faculty of Sciences and Engineering in my university. Prof. T. Yamada, here, is my colleague in the same faculty. I know that the nuclear physics is one of the most active academic fields in the world. In fact, about half of the participants, namely, more than 50 scientists, come from abroad in this conference. Moreover, I know that the nuclear physics is related to not only the other fundamental physics such as the elementary particle physics and astrophysics but also chemistry, medical sciences, medical cares, and radiation metrology

  13. Outstanding Science Trade Books for Students K-12

    ERIC Educational Resources Information Center

    Texley, Juliana

    2009-01-01

    Today's classrooms have no real walls! Students explore the world on field trips, during virtual journeys on the world wide web, and through the books they read. These pathways help them fly to the ends of the universe to satisfy their scientific curiosity. Again this year, the professionals of the NSTA/CBC Review Panel for Outstanding Science…

  14. The RASD Outstanding Reference Sources Committee: Retrospect and Prospect.

    ERIC Educational Resources Information Center

    Sheets, Janet; Masters, Deborah C.

    1981-01-01

    Describes the Reference and Adult Services Division's Outstanding Reference Sources Committee procedures for preparation of the 1979 listing, discusses expansion to include nonbook sources, and provides a retrospective list of nonbook sources selected by the 1979-80 committee. Nonbook sources include microforms and databases. Six references are…

  15. Student Observations of Outstanding Teaching: Implications for Marketing Educators

    ERIC Educational Resources Information Center

    Faranda, William T.; Clarke, Irvine, III

    2004-01-01

    In this article, the authors heed the call to explore the attributes of an outstanding professor "by conducting in-depth interviews with students." The study reveals five predominant themes (rapport, delivery, fairness, knowledge and credibility, organization, and preparation) of teaching excellence, as perceived by students, through…

  16. The Classroom Interaction of Outstanding Foreign Language Teachers

    ERIC Educational Resources Information Center

    Moskowitz, Gertrude

    1976-01-01

    The classroom interaction of ten foreign language teachers identified as outstanding was studied and compared with that of a group of typical teachers. The FLint system of interaction analysis and anecdotal records were used to collect data as the teachers taught four different lessons. Differences between the groups are discussed. (Author/RM)

  17. More Outstanding Nonsense: A Critique of Ofsted Criteria

    ERIC Educational Resources Information Center

    Richards, Colin

    2015-01-01

    The Office for Standards in Education's most recently published criteria for "outstanding" teaching are scrutinised and found wanting. They are seen as unrealistic for teachers to meet and equally unrealistic as criteria for use by inspectors. An explanation is offered as to why they are framed as they are and an alternative, more…

  18. Information Technology: Making It All Fit. Track VI: Outstanding Applications.

    ERIC Educational Resources Information Center

    CAUSE, Boulder, CO.

    Seven papers from the 1988 CAUSE conference's Track VI, Outstanding Applications, are presented. They include: "Designing DB2 Data Bases Using Entity-Relationship Modeling: A Case Study--The LSU System Worker's Compensation Project" (Cynthia M. Hadden and Sara G. Zimmerman); "Integrating Information Technology: Prerequisites for…

  19. American School & University Educational Interiors Showcase: Outstanding Designs.

    ERIC Educational Resources Information Center

    American School & University, 1999

    1999-01-01

    Presents the table of contents of award winners for outstanding architectural design in educational facilities. Winning designs listed cover those for common areas, classrooms, libraries and media centers, cafeterias/food service, auditoriums, laboratories, multipurpose rooms, physical/recreational centers, residence halls, student/service…

  20. Glimpses into Pacific Lives: Some Outstanding Women (Revised).

    ERIC Educational Resources Information Center

    Simon-McWilliams, Ethel, Comp.; Green, Karen Reed, Ed.

    This booklet provides brief biographies of women who have made outstanding contributions to the social and economic development of these Pacific islands: American Samoa, the Republic of Belau, the Federated States of Micronesia, Guam, Hawaii, the Marshall islands, and the Northern Mariana Islands. The 66 women profiled include educators, health…

  1. A World of Stories: 2008 Outstanding International Books

    ERIC Educational Resources Information Center

    Angus, Carolyn

    2008-01-01

    For the first time in its three-year history, the United States Board on Books for Young People's (USBBY) Outstanding International Books list includes foreign titles coming from publishers with U.S. distributors, as well as those acquired by U.S. publishers. The selection committee read 380 books published in 2007, narrowing down the best of…

  2. National PTA Selects Outstanding Educator of the Year.

    ERIC Educational Resources Information Center

    Reynolds, Pamela

    1985-01-01

    Principal Gene Bedley of El Camino Real School in Irvine, California, is the 1985 winner of the National PTA Hearst Outstanding Educator of the Year Award. Mr. Bedley believes that education is a shared experience and builds strong relationships with teachers, parents, and children. Some of his techniques are described. (MT)

  3. Outstanding Negro High School Students: A One-Year Followup.

    ERIC Educational Resources Information Center

    Burgdorf, Kenneth

    In the fall of 1964, 4,288 students were nominated for participation in the 1st annual competition of the National Achievement Scholarship Program for outstanding Negro students. The students were divided into 3 groups--Scholars, Finalists and Commended. The highest competition status group, the Scholars, were awarded 4-year college scholarships…

  4. Outstanding Science Trade Books for Students K-12

    ERIC Educational Resources Information Center

    Texley, Juliana

    2008-01-01

    Each of these outstanding selections defies the traditional image of a child "curling up with a good book." Yes, they can be a source of great personal reading, encouraging students of all ages to stretch their skills and their imagination as they interact with the printed page. But these journeys of the scientific imagination seldom end with the…

  5. 11 CFR 9004.9 - Net outstanding qualified campaign expenses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... outstanding campaign obligations under paragraph (a)(1) of this section shall not include any accounts payable... accounts receivable. If the committee determines that an account receivable of $500 or more, including any... records showing the original amount of the account receivable, copies of correspondence and memoranda...

  6. 29 CFR 4281.18 - Outstanding claims for withdrawal liability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... for one or more series of equal payments, the plan sponsor shall value each series of payments as an... liability payments provides for one or more payments that are not part of a series of equal payments as... time. (c) Claims against other employers. The plan sponsor shall value at zero any outstanding...

  7. Outstanding Science Trade Books for Students K-12.

    ERIC Educational Resources Information Center

    Science and Children, 2002

    2002-01-01

    Introduces a list of outstanding science trade books for grade levels K-12 in the areas of Archaeology, Anthropology, Paleontology, Biography, Life Sciences, Integrated Science, Physical Science, Science Related Careers, and Technology and Engineering. Includes information on the selection process. (YDS)

  8. Outstanding Science Trade Books for Students K-12.

    ERIC Educational Resources Information Center

    Science Scope, 2002

    2002-01-01

    Presents a list of outstanding science trade books published in 2001 for use in the K-12 grade levels. Includes the areas of archaeology, anthropology, and paleontology; biography; life sciences; integrated science; physical sciences; science related careers; and technology and engineering. Provides information on the books and the selection…

  9. Outstanding Science Trade Books for Children for 1997.

    ERIC Educational Resources Information Center

    Science and Children, 1997

    1997-01-01

    This list, published by the National Science Teachers Association and the Children's Book Council, contains titles and annotations of outstanding science trade books. It is also a popular service for teachers and media specialists. The books are grouped by topic areas including anthropology and paleontology, biography, Earth science, environment…

  10. Outstanding Science Trade Books for Children for 1998.

    ERIC Educational Resources Information Center

    Science and Children, 1998

    1998-01-01

    The books listed in this annotated bibliography were selected as outstanding children's trade books published in 1997. Titles are categorized as biography, environment and ecology, integrated science, life science, paleontology, physical science, and science-related careers. Each entry includes a descriptive annotation along with a code indicating…

  11. [American School and University Interiors Showcase: 1998 Outstanding Designs].

    ERIC Educational Resources Information Center

    Argon, Joe, Ed.

    1998-01-01

    Presents 50 outstanding awards for learning-environment designs as determined by an expert panel of judges. Each citation provides the school name and location, the name of the architectural firm, cost and square-footage figures, and a brief summary of the project. Photographs and some floorplan drawings are included. (GR)

  12. A Kaleidoscope for Learning. Outstanding School Reform Programs.

    ERIC Educational Resources Information Center

    Shaughnessy, Lana, Ed.; Morris, Joann Sebastian, Ed.

    This publication features profiles of 25 outstanding school reform programs at Bureau of Indian Affairs schools. These innovative schools have captured various aspects of school reform that encompass more challenging, real world curricula; school-to-work transitions; new ways of assessing student achievement; higher order thinking and…

  13. A Portfolio of Outstanding Americans of Mexican Descent.

    ERIC Educational Resources Information Center

    Lelevier, Benjamin, Jr.

    A cross section of Mexican American achievement is presented in a portfolio of 37 portraits of outstanding Americans of Mexican descent. Drawn in black and white on heavy paper stock by Mr. David L. Rodriguez, the sketches are suitable for display purposes. With the likenesses are biographical sketches in both English and Spanish which were…

  14. Outstanding Science Trade Book for Students K-12

    ERIC Educational Resources Information Center

    Texley, Juliana

    2010-01-01

    What makes an outstanding book for a young reader? Although it would be hard to create a rubric for every book, experienced teachers recognize them quickly. They fascinate and captivate with both their content and style. Award-winning trade books inspire young readers to want more... more information, more books, more inquiry, more science. The…

  15. World Class: USBBY's Outstanding International Books for Young People

    ERIC Educational Resources Information Center

    Angus, Carolyn

    2009-01-01

    Some of the world's best children's book artists got together to help Amnesty International celebrate the Universal Declaration of Human Rights' 60th anniversary in "We Are All Born Free," one of the 42 titles recommended by the fourth annual United States Board on Books for Young People's (USBBY) Outstanding International Books…

  16. Instructional Leadership in Greek and English Outstanding Schools

    ERIC Educational Resources Information Center

    Kaparou, Maria; Bush, Tony

    2016-01-01

    Purpose: The purpose of this paper is to examine instructional leadership (IL) in outstanding secondary schools within a centralised (Greece) and a partially decentralised (England) education context. Design/methodology/approach: Since the purpose of the study is exploratory, the researchers adopt a qualitative approach, employing a series of four…

  17. Using physiologically based pharmacokinetic modeling to address nonlinear kinetics and changes in rodent physiology and metabolism due to aging and adaptation in deriving reference values for propylene glycol methyl ether and propylene glycol methyl ether acetate.

    SciTech Connect

    Kirman, C R.; Sweeney, Lisa M.; Corley, Rick A.; Gargas, M L.

    2005-04-01

    Reference values, including an oral reference dose (RfD) and an inhalation reference concentration (RfC), were derived for propylene glycol methyl ether (PGME), and an oral RfD was derived for its acetate (PGMEA). These values were based upon transient sedation observed in F344 rats and B6C3F1 mice during a two-year inhalation study. The dose-response relationship for sedation was characterized using internal dose measures as predicted by a physiologically based pharmacokinetic (PBPK) model for PGME and its acetate. PBPK modeling was used to account for changes in rodent physiology and metabolism due to aging and adaptation, based on data collected during weeks 1, 2, 26, 52, and 78 of a chronic inhalation study. The peak concentration of PGME in richly perfused tissues was selected as the most appropriate internal dose measure based upon a consideration of the mode of action for sedation and similarities in tissue partitioning between brain and other richly perfused tissues. Internal doses (peak tissue concentrations of PGME) were designated as either no-observed-adverse-effect levels (NOAELs) or lowest-observed-adverse-effect levels (LOAELs) based upon the presence or absence of sedation at each time-point, species, and sex in the two year study. Distributions of the NOAEL and LOAEL values expressed in terms of internal dose were characterized using an arithmetic mean and standard deviation, with the mean internal NOAEL serving as the basis for the reference values, which was then divided by appropriate uncertainty factors. Where data were permitting, chemical-specific adjustment factors were derived to replace default uncertainty factor values of ten. Nonlinear kinetics are were predicted by the model in all species at PGME concentrations exceeding 100 ppm, which complicates interspecies and low-dose extrapolations. To address this complication, reference values were derived using two approaches which differ with respect to the order in which these extrapolations

  18. EDITORIAL: Announcing the 2008 Measurement Science and Technology Outstanding Paper Awards Announcing the 2008 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Fujii, Kenichi; Regtien, Paul

    2009-05-01

    From 1991 to 2004, Measurement Science and Technology had awarded a Best Paper prize. The Editorial Board of this journal believed that such a prize was an opportunity to thank authors for submitting their work, and that it served as an integral part of the on-going quality review of the journal. The current breadth of topical areas that are covered by MST has made it advisable to expand the recognition of excellent publications. Hence, since 2005 the Editorial Board Members have presented 'Outstanding Paper Awards' in four subject categories: Measurement Science; Fluid Mechanics; Precision Measurements; and Sensors and Sensing Systems. 2008 Award Winners—Measurement Science Noise level estimation in weakly nonlinear slowly time-varying systems J R M Aerts, J Lataire, R Pintelon and J J J Dirckx Laboratory of Biomedical Physics, Universiteit Antwerpen, Groenenborgerlaan 171, 2020 Antwerp, Belgium and Department of Fundamental Electricity and Instrumentation (ELEC), Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium This paper [1] examines new methods to perform noise estimation in weakly nonlinear time-varying systems. In a clear presentation that describes the problem, the paper concentrates on weakly nonlinear phenomena in the acoustic regime. However, both the concepts and theory developed have wide applicability in other fields within measurement science wherever there is a time-varying nonlinear response. The theory uses two methods to estimate noise. The first is called the background frequency method, and the second is a periodic difference method. Both methods have their advantages, and disadvantages, which the authors highlight in a balanced account. They also spend some effort in validating the two approaches. Just as importantly, applications of the theory are presented as two experimental case histories. The first is a study of a vibrating membrane from a high quality microphone. This is an example of a time-invariant system, and the

  19. 36 CFR 292.67 - Operating plan approval-outstanding mineral rights.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-outstanding mineral rights. 292.67 Section 292.67 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE NATIONAL RECREATION AREAS Smith River National Recreation Area Outstanding Mineral Rights § 292.67 Operating plan approval—outstanding mineral rights. (a) Upon receipt of an operating...

  20. 36 CFR 292.67 - Operating plan approval-outstanding mineral rights.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-outstanding mineral rights. 292.67 Section 292.67 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE NATIONAL RECREATION AREAS Smith River National Recreation Area Outstanding Mineral Rights § 292.67 Operating plan approval—outstanding mineral rights. (a) Upon receipt of an operating...

  1. 36 CFR 292.67 - Operating plan approval-outstanding mineral rights.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-outstanding mineral rights. 292.67 Section 292.67 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE NATIONAL RECREATION AREAS Smith River National Recreation Area Outstanding Mineral Rights § 292.67 Operating plan approval—outstanding mineral rights. (a) Upon receipt of an operating...

  2. 36 CFR 292.67 - Operating plan approval-outstanding mineral rights.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-outstanding mineral rights. 292.67 Section 292.67 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE NATIONAL RECREATION AREAS Smith River National Recreation Area Outstanding Mineral Rights § 292.67 Operating plan approval—outstanding mineral rights. (a) Upon receipt of an operating...

  3. 36 CFR 292.67 - Operating plan approval-outstanding mineral rights.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-outstanding mineral rights. 292.67 Section 292.67 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE NATIONAL RECREATION AREAS Smith River National Recreation Area Outstanding Mineral Rights § 292.67 Operating plan approval—outstanding mineral rights. (a) Upon receipt of an operating...

  4. 12 CFR 215.7 - Extensions of credit outstanding on March 10, 1979.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Extensions of credit outstanding on March 10... (REGULATION O) § 215.7 Extensions of credit outstanding on March 10, 1979. (a) Any extension of credit that was outstanding on March 10, 1979, and that would, if made on or after March 10, 1979, violate §...

  5. Nonlinear Structural Analysis

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Nonlinear structural analysis techniques for engine structures and components are addressed. The finite element method and boundary element method are discussed in terms of stress and structural analyses of shells, plates, and laminates.

  6. Mercury biogeochemistry: Paradigm shifts, outstanding issues and research needs

    NASA Astrophysics Data System (ADS)

    Sonke, Jeroen E.; Heimbürger, Lars-Eric; Dommergue, Aurélien

    2013-05-01

    Half a century of mercury research has provided scientists and policy makers with a detailed understanding of mercury toxicology, biogeochemical cycling and past and future impacts on human exposure. The complexity of the global biogeochemical mercury cycle has led to repeated and ongoing paradigm shifts in numerous mercury-related disciplines and outstanding questions remain. In this review, we highlight some of the paradigm shifts and questions on mercury toxicity, the risks and benefits of seafood consumption, the source of mercury in seafood, and the Arctic mercury cycle. We see a continued need for research on mercury toxicology and epidemiology, for marine mercury dynamics and ecology, and for a closer collaboration between observational mercury science and mercury modeling in general. As anthropogenic mercury emissions are closely tied to the energy cycle (in particular coal combustion), mercury exposure to humans and wildlife are likely to persist unless drastic emission reductions are put in place.

  7. Compendium of meteorology scientific issues of 1950 still outstanding

    NASA Technical Reports Server (NTRS)

    Vaughan, W. W.

    1986-01-01

    The Compendium of Meteorology was published in 1951 by the American Meteorological Society. A review was made of the Compendium of Meteorology to identify the studies and future needs which the authors expressed in their papers. The needs as seen by the authors are organized into sections and papers following the format of the Compendium of Meteorology. In some cases the needs they identified are as valid today as they were in 1951. In other cases one will easily be able to identify examples where significant progress has been made. It is left to the individual scientists and scientific program managers to assess whether significant progress has been made over the past thirty-five years on these outstanding scientific issues.

  8. Outstanding student papers at the 1990 Spring Meeting

    NASA Astrophysics Data System (ADS)

    Three students received awards for outstanding presentations at this year's Spring Meeting. Several AGU sections award such certificates to recognize excellence in content and presentation, and to encourage student participation in AGU's national meetings.John Stamatakos was selected by the Geomagnetism and Paleomagnetism Section for his poster presentation, “Strained Remanence in the Mauch Chunk Formation.” Stamatakos received his B.A. from Franklin and Marshall College, Lancaster, Pennsylvania, (1981), and his M.S. (1988) and Ph.D. (September, 1990) from Lehigh University, Bethlehem, Pennsylvania. He currently has a 1-year postdoctoral position at the Swiss Institute of Technology (ETH) in Zurich with William Lowrie and Ann Hirt.

  9. Outstanding challenges limiting the development of climate services in Europe

    NASA Astrophysics Data System (ADS)

    Buontempo, Carlo; Soares, Marta Bruno; Liggins, Felicity

    2016-04-01

    Climate services attempt to make the available (or forthcoming) climate knowledge more usable by decision and policy makers in the development of a climate smart society. Since the launch of the Global Framework for Climate Services in 2009 there has been an exponential increase in investment in the development and delivery of climate services, leading to an array of projects and initiatives across Europe. However, to date little attention has been given to understanding the different ways in which climate services are defined, implemented, and evaluated in Europe. In addition, other aspects such as how to pursue the necessary processes of co-production, which business models to apply, and the implications for the careers of scientists and others involved in the development of climate services are also crucial elements that need to be further examined and discussed. Such aspects are critical to the future development of climate services as they have the potential to significantly constrain the growth of climate services in Europe. Starting from a set of questions that have arisen within some of the most prominent climate services projects and initiatives in Europe, our paper highlights and expands on the outstanding challenges that need to be resolved by both the scientific community and the funders in order to ensure climate services can prosper and grow in Europe.

  10. Sophus Peter Tromholt: an outstanding pioneer in auroral research

    NASA Astrophysics Data System (ADS)

    Moss, K.; Stauning, P.

    2012-03-01

    The Danish school teacher Sophus Peter Tromholt (1851-1896) was self-taught in physics, astronomy, and auroral sciences. Still, he was one of the brightest auroral researchers of the 19th century. He was the first scientist ever to organize and analyse correlated auroral observations over a wide area (entire Scandinavia) moving away from incomplete localized observations. Tromholt documented the relation between auroras and sunspots and demonstrated the daily, seasonal and solar cycle-related variations in high-latitude auroral occurrence frequencies. Thus, Tromholt was the first ever to deduce from auroral observations the variations associated with what is now known as the auroral oval termed so by Khorosheva (1962) and Feldstein (1963) more than 80 yr later. He made reliable and accurate estimates of the heights of auroras several decades before this important issue was finally settled through Størmer's brilliant photographic technique. In addition to his three major scientific works (Tromholt, 1880a, 1882a, and 1885a), he wrote numerous short science notes and made huge efforts to collect historical auroral observations (Tromholt, 1898). Furthermore, Tromholt wrote a large number of popular science articles in newspapers and journals and made lecture tours all over Scandinavia and Germany, contributing to enhance the public educational level and awareness. He devoted most of his life to auroral research but as a self-taught scientist, he received little acclaim within the contemporary academic scientific society. With his non-academic background, trained at a college of education - not a university - he was never offered a position at a university or a research institution. However, Sophus Tromholt was an outstanding pioneer in auroral research.

  11. Final report on LDRD project : outstanding challenges for AlGaInN MOCVD.

    SciTech Connect

    Mitchell, Christine Charlotte; Follstaedt, David Martin; Russell, Michael J.; Cross, Karen Charlene; Wang, George T.; Creighton, James Randall; Allerman, Andrew Alan; Koleske, Daniel David; Lee, Stephen Roger; Coltrin, Michael Elliott

    2005-03-01

    The AlGaInN material system is used for virtually all advanced solid state lighting and short wavelength optoelectronic devices. Although metal-organic chemical vapor deposition (MOCVD) has proven to be the workhorse deposition technique, several outstanding scientific and technical challenges remain, which hinder progress and keep RD&A costs high. The three most significant MOCVD challenges are: (1) Accurate temperature measurement; (2) Reliable and reproducible p-doping (Mg); and (3) Low dislocation density GaN material. To address challenge (1) we designed and tested (on reactor mockup) a multiwafer, dual wavelength, emissivity-correcting pyrometer (ECP) for AlGaInN MOCVD. This system simultaneously measures the reflectance (at 405 and 550 nm) and emissivity-corrected temperature for each individual wafer, with the platen signal entirely rejected. To address challenge (2) we measured the MgCp{sub 2} + NH{sub 3} adduct condensation phase diagram from 65-115 C, at typical MOCVD concentrations. Results indicate that it requires temperatures of 80-100 C in order to prevent MgCp{sub 2} + NH{sub 3} adduct condensation. Modification and testing of our research reactor will not be complete until FY2005. A new commercial Veeco reactor was installed in early FY2004, and after qualification growth experiments were conducted to improve the GaN quality using a delayed recovery technique, which addresses challenge (3). Using a delayed recovery technique, the dislocation densities determined from x-ray diffraction were reduced from 2 x 10{sup 9} cm{sup -2} to 4 x 10{sup 8} cm{sup -2}. We have also developed a model to simulate reflectance waveforms for GaN growth on sapphire.

  12. Outstanding Books for the College Bound: Titles and Programs for a New Generation

    ERIC Educational Resources Information Center

    Carstensen, Angela, Ed.

    2011-01-01

    Connecting teens to books they'll truly enjoy is the aim of every young adult librarian, and the completely revamped guide "Outstanding Books for the College Bound" will give teen services staff the leg up they need to make it happen. Listing nearly 200 books deemed outstanding for the college bound by the Young Adult Library Services Association…

  13. 7 CFR 1901.508 - Servicing of insured notes outstanding with investors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 12 2012-01-01 2012-01-01 false Servicing of insured notes outstanding with investors. 1901.508 Section 1901.508 Agriculture Regulations of the Department of Agriculture (Continued) RURAL... Ownership and Insured Notes § 1901.508 Servicing of insured notes outstanding with investors. The...

  14. 11 CFR 9008.10 - Documentation of disbursements; net outstanding convention expenses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 11 Federal Elections 1 2014-01-01 2014-01-01 false Documentation of disbursements; net outstanding... Expenditures by National Committees and Convention Committees § 9008.10 Documentation of disbursements; net... shall present these records to the Commission on request. (g) Net outstanding convention expenses....

  15. 7 CFR 1901.508 - Servicing of insured notes outstanding with investors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false Servicing of insured notes outstanding with investors. 1901.508 Section 1901.508 Agriculture Regulations of the Department of Agriculture (Continued) RURAL... Ownership and Insured Notes § 1901.508 Servicing of insured notes outstanding with investors. The...

  16. 7 CFR 1901.508 - Servicing of insured notes outstanding with investors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 12 2013-01-01 2013-01-01 false Servicing of insured notes outstanding with investors. 1901.508 Section 1901.508 Agriculture Regulations of the Department of Agriculture (Continued) RURAL... Ownership and Insured Notes § 1901.508 Servicing of insured notes outstanding with investors. The...

  17. 7 CFR 1901.508 - Servicing of insured notes outstanding with investors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 12 2014-01-01 2013-01-01 true Servicing of insured notes outstanding with investors. 1901.508 Section 1901.508 Agriculture Regulations of the Department of Agriculture (Continued) RURAL... Ownership and Insured Notes § 1901.508 Servicing of insured notes outstanding with investors. The...

  18. 7 CFR 1901.508 - Servicing of insured notes outstanding with investors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 12 2011-01-01 2011-01-01 false Servicing of insured notes outstanding with investors. 1901.508 Section 1901.508 Agriculture Regulations of the Department of Agriculture (Continued) RURAL... Ownership and Insured Notes § 1901.508 Servicing of insured notes outstanding with investors. The...

  19. Outstanding issues concerning future thermospheric model improvements and applications

    NASA Astrophysics Data System (ADS)

    Owens, Jerry

    Significant improvements in the accuracy of thermosphere models have recently been achieved for the first time in more than thirty years. However, additional important issues remain to be addressed in the future in order to further improve both the current and future estimates of density values that affect the various assets, satellite and spacecraft, that society has come to depend upon. These include high latitude processes that are not yet treated adequately in the models, as well as accuracy of future estimates of model inputs such as both short and long term solar activity plus physical model structure and reliability. Orbiting spacecraft are affected by the total density as well as its composition. These parameters affect satellite and spacecraft tracking, operations, performance, orbital debris, lifetime estimation, and logistics planning for re-boost activities. This paper will review the various issues and relative importance for users of thermospheric model products.

  20. Outstanding Results--Tomorrow's Challenge. Adult Education Changes Lives: Recipients of the 1998-1999 Secretary's Awards for Outstanding Adult Education and Literacy Programs.

    ERIC Educational Resources Information Center

    Office of Vocational and Adult Education (ED), Washington, DC. Div. of Adult Education and Literacy.

    This book profiles the achievements and best practices of 10 outstanding adult education and literacy education programs in nine states that received the 1998-99 Secretary's Awards from U.S. Secretary of Education Richard W. Riley. The programs were selected from 35 nominated programs using the following criteria: program design, instructional…

  1. Some Lady! A Conversation with Dorothy Watson, Outstanding Educator in the Language Arts.

    ERIC Educational Resources Information Center

    Bishop, Rudine Sims

    2002-01-01

    Presents a conversation with Dorothy Watson, the 2002 Outstanding Educator in the Language Arts recipient. Hopes that this profile will provide insight into Dorothy Watson and her intellectual foundations, her humaneness, and her passion for teaching and learning. (SG)

  2. N.H. Dept. of Environmental Services Civil Servant Recognized for Outstanding Service

    EPA Pesticide Factsheets

    Ray Gordon, Septage Coordinator of the N.H. Dept. of Environmental Services (NHDES) is being honored with a 2014 Regional Wastewater Treatment Plant Trainer of the Year Excellence Award by EPA. Mr. Gordon has done an outstanding job over

  3. UMASS-Lowell Professor Recognized by EPA for Outstanding Lifetime Achievement Service

    EPA Pesticide Factsheets

    Donald Pottle, Professor at the UMass – Lowell, was honored recently by EPA for the outstanding job he performed over the years both facilitating & performing hands on training for thousands of wastewater treatment plant operators throughout New England.

  4. Blood Falls: A novel management approach for a subglacial feature of outstanding scientific importance

    NASA Astrophysics Data System (ADS)

    Carr, J. R.; Penhale, P. A.; Dahood, A.; Biletnikoff, N.; Harris, C. M.

    2012-04-01

    Blood Falls is a subglacial feature located in the ablation zone of the Taylor Glacier, Taylor Valley, McMurdo Dry Valleys, Antarctica. Blood Falls has a unique physical configuration, microbial ecology and geochemistry and consists of a subglacial brine reservoir and an iron-rich, saline surface discharge at the Taylor Glacier terminus. The feature provides a rare opportunity to sample properties of a subglacial reservoir and its ecosystem without the need for direct contact and is a key site for exobiological studies. The Blood Falls subglacial feature is globally unique and of outstanding scientific importance. As such, it warrants special protection from potential damage by drilling and/or surface activities. Moreover, currently subglacial environments are not represented in the Antarctic protected area network. To address these points, the United States National Science Foundation is working with the scientific community to develop at Blood Falls the first subglacial protected area in Antarctica. The protected area aims to maintain the integrity of the Blood Falls system, whilst allowing continued access for scientific and management purposes. Novel management approaches are being designed to protect the values of the site in three dimensions. Specific guidelines on activities conducted within the area, most notably drilling and coring, are being defined in a management plan. This new approach incorporates uncertainties in the location of the Blood Falls brine reservoir and the connectivity of the subglacial hydrological system of the Taylor Glacier. The management approaches employed at Blood Falls draw on the experience of the subglacial research community and potentially offer an effective framework for the protection of other subglacial environments.

  5. Nonlinear Waves

    DTIC Science & Technology

    1989-06-15

    following surprising situation. Namely associated with the integrable nonlinear Schrodinger equations are standard numerical schemes which exhibit at...36. An Initial Boundary Value Problem for the Nonlinear Schrodinger Equations , A.S. Fokas, Physica D March 1989. 37. Evolution Theory, Periodic... gravity waves and wave excitation phenomena related to moving pressure distributions; numerical approximation and computation; nonlinear optics; and

  6. Announcing the 2013 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Yacoot, Andrew; Tadigadapa, Srinivas; Peters, Kara

    2014-07-01

    Since 1991, Measurement Science and Technology has awarded a Best Paper prize. The Editorial Board of this journal believe that such a prize is an opportunity to thank authors for submitting their work, and serves as an integral part of the on-going quality review of the journal. The current breadth of topical areas that are covered by MST has made it advisable to expand the recognition of excellent publications. Hence, since 2005 the Editorial Board have presented 'Outstanding Paper Awards'. This year awards were presented in the areas of Fluid Mechanics, Measurement Science, Precision Measurement, Sensors and Sensing Systems, and Optical and Laser-based Techniques. Although the categories mirror subject sections in the journal, the Editorial Board consider articles from all categories in the selection process. 2013 Award Winner—Fluid Mechanics Extraction of skin-friction fields from surface flow visualizations Tianshu Liu Department of Mechanical and Aerospace Engineering, Western Michigan University, Kalamazoo, MI 49008, USA The skin friction or wall shear stress, τ w, for a wall bounded turbulent flow is a quantity of fundamental importance. It is the basis for the wall unit, ν/u τ (kinematic viscosity/friction velocity: [τ w/ρ ]1/2), which establishes the intrinsic length scale in the flow. The selected paper [1] provides a comprehensive review of—and builds upon—prior techniques to obtain τ w values over an area of interest for flow past complex geometries. The quantities that can be measured by optical imaging are shown to be related to the skin friction by the optical flow equation, which in turn is solved numerically as an inverse problem via the variational approach. The paper provides a well defined set of guidelines for other investigators. Detailed examples of skin-friction measurements using luminescent oil films as well as temperature- and pressure-sensitive paints are presented. Quantitative uncertainty estimates are included in the

  7. Addressing Ozone Layer Depletion

    EPA Pesticide Factsheets

    Access information on EPA's efforts to address ozone layer depletion through regulations, collaborations with stakeholders, international treaties, partnerships with the private sector, and enforcement actions under Title VI of the Clean Air Act.

  8. EDITORIAL: Announcing the 2012 Measurement Science and Technology Outstanding Paper Awards Announcing the 2012 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Yacoot, Andrew; Regtien, Paul; Peters, Kara

    2013-07-01

    Since 1991, Measurement Science and Technology has awarded a Best Paper prize. The Editorial Board of this journal believes that such a prize is an opportunity to thank authors for submitting their work, and serves as an integral part of the on-going quality review of the journal. The current breadth of topical areas that are covered by MST has made it advisable to expand the recognition of excellent publications. Hence, since 2005 the Editorial Board have presented 'Outstanding Paper Awards'. This year awards were presented in the areas of 'Measurement Science' and 'Fluid Mechanics'. Although the categories mirror subject sections in the journal, the Editorial Board consider articles from all categories in the selection process. 2012 Award Winners—Measurement Science Physical characterization and performance evaluation of an x-ray micro-computed tomography system for dimensional metrology applications J Hiller1, M Maisl2 and L M Reindl3 1 Department of Mechanical Engineering, Technical University of Denmark (DTU), Produktionstorvet, Building 425, 2800 Kgs Lyngby, Denmark 2 Development Center for X-Ray Technology (EZRT), Fraunhofer Institute for Non-Destructive Testing (IZFP), Campus E3 1, 66123 Saarbrücken, Germany 3 Laboratory for Electrical Instrumentation, Institute for Microsystem Technology (IMTEK), University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany This year's award goes to another paper [1] dealing with micro-measurements, using a scientific measurement technique that is both old and traditional. However, it is the advent of modern technology with computational techniques that have offered new insights into the capability of the measurement method. The paper describes an x-ray computed tomography (CT) system. Such systems are increasingly used in production engineering, where non-destructive measurements of the internal geometries of workpieces can be made with high information density. CT offers important alternatives to tactile

  9. Nonlinear supratransmission

    NASA Astrophysics Data System (ADS)

    Geniet, F.; Leon, J.

    2003-05-01

    A nonlinear system possessing a natural forbidden band gap can transmit energy of a signal with a frequency in the gap, as recently shown for a nonlinear chain of coupled pendulums (Geniet and Leon 2002 Phys. Rev. Lett. 89 134102). This process of nonlinear supratransmission, occurring at a threshold that is exactly predictable in many cases, is shown to have a simple experimental realization with a mechanical chain of pendulums coupled by a coil spring. It is then analysed in more detail. First we go to different (nonintegrable) systems which do sustain nonlinear supratransmission. Then a Josephson transmission line (a one-dimensional array of short Josephson junctions coupled through superconducting wires) is shown to also sustain nonlinear supratransmission, though being related to a different class of boundary conditions, and despite the presence of damping, finiteness, and discreteness. Finally, the mechanism at the origin of nonlinear supratransmission is found to be a nonlinear instability, and this is briefly discussed here.

  10. EDITORIAL: Announcing the 2005 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Fujii, Kenichi; Regtien, Paul

    2006-06-01

    atomic force microscope (AFM) is combined with differential laser interferometers so that the atomic scale resolution of the AFM is accurately calibrated by optical interferometry, achieving an unprecedented uncertainty of 0.2 nm in measuring the pitches of about 50 nm. The instrument also calibrates the pitches in a wide scanning range. This paper analysed the uncertainty of the measurement in detail, helping to provide users with reliable certified reference materials for one-dimensional grating standards. 2005 Award Winners—Sensors and Sensing Systems The 2005 Measurement Science and Technology Outstanding Paper Award in the Sensors and Sensing Systems category has been awarded to Nicola Bowler and Yongqiang Huang (Iowa State University, USA) for the article 'Electrical conductivity measurement of metal plates using broadband eddy-current and four-point methods', published in volume 16, issue 11, pp 2193 2200. In making their recommendation the Sensors and Sensing Systems working group chaired by Professor Paul Regtien gave the following endorsement: The paper addresses two methods to measure the electrical conductivity of metal plates of various materials. In particular for ferromagnetic plates, traditional methods show relatively large measurement uncertainties. In this paper, the origins of these large inaccuracies are studied, and two alternative methods are presented that yield much better accuracies. Both methods—a broadband eddy-current and a four-point contact scheme—are extensively analysed theoretically as well as experimentally. The results are compared with other published data, for plates of brass, stainless steel and spring steel. An uncertainty analysis reveals the superiority of the newly introduced methods in the case of steel. The four-point method has the advantage of being easy to use. The paper is well-structured, with a good balance between theory and experiments, and a clear presentation of the measurement data and associated uncertainties

  11. Addressing Social Issues.

    ERIC Educational Resources Information Center

    Schoebel, Susan

    1991-01-01

    Maintains that advertising can help people become more aware of social responsibilities. Describes a successful nationwide newspaper advertising competition for college students in which ads address social issues such as literacy, drugs, teen suicide, and teen pregnancy. Notes how the ads have helped grassroots programs throughout the United…

  12. Invitational Addresses, 1965.

    ERIC Educational Resources Information Center

    Gates, Arthur I.; And Others

    The full texts of invitational addresses given at the 1965 International Reading Association (IRA) Convention in Detroit, Michigan, by six recipients of IRA citation awards are presented. Gates suggests steps IRA should take to revive and redirect reading research. McCallister discusses the implications of the changing and expanding vocabulary of…

  13. States Address Achievement Gaps.

    ERIC Educational Resources Information Center

    Christie, Kathy

    2002-01-01

    Summarizes 2 state initiatives to address the achievement gap: North Carolina's report by the Advisory Commission on Raising Achievement and Closing Gaps, containing an 11-point strategy, and Kentucky's legislation putting in place 10 specific processes. The North Carolina report is available at www.dpi.state.nc.us.closingthegap; Kentucky's…

  14. Addressing Sexual Harassment

    ERIC Educational Resources Information Center

    Young, Ellie L.; Ashbaker, Betty Y.

    2008-01-01

    This article discusses ways on how to address the problem of sexual harassment in schools. Sexual harassment--simply defined as any unwanted and unwelcome sexual behavior--is a sensitive topic. Merely providing students, parents, and staff members with information about the school's sexual harassment policy is insufficient; schools must take…

  15. Content Addressable Memory Project

    DTIC Science & Technology

    1990-11-01

    The Content Addressable M1-emory Project consists of the development of several experimental software systems on an AMT Distributed Array Processor...searching (database) compiler algorithms memory management other systems software) Linear C is an unlovely hybrid language which imports the CAM...memory from AMT’s operating system for the DAP; how- ever, other than this limitation, the memory management routines work exactly as their C counterparts

  16. Learning to Listen: 15th Annual Peggy Glanville-Hicks Address 2013

    ERIC Educational Resources Information Center

    Lacey, Genevieve

    2013-01-01

    The New Music Network established the Peggy Glanville-Hicks Address in 1999 in honour of one of Australia's great international composers. It is an annual forum for ideas relating to the creation and performance of Australian music. In the spirit of the great Australian composer Peggy Glanville-Hicks, an outstanding advocate of Australian music…

  17. What Would Peggy Do? 14th Annual Peggy Glanville-Hicks Address 2012

    ERIC Educational Resources Information Center

    Harvey, Michael Kieran

    2012-01-01

    The New Music Network established the Peggy Glanville-Hicks Address in 1999 in honour of one of Australia's great international composers. It is an annual forum for ideas relating to the creation and performance of Australian music. In the spirit of the great Australian composer Peggy Glanville-Hicks, an outstanding advocate of Australian music…

  18. Out of the Mouths of Babes: What Do Secondary Students Believe about Outstanding Teachers?

    ERIC Educational Resources Information Center

    Williams, Patricia; Sullivan, Sam; Kohn, Lawrence

    2012-01-01

    Pre-service teachers taking a Human Growth and Learning course and graduate students enrolled in a Classroom Management course wrote letters to secondary students to gather responses on traits of an outstanding educator. A theoretical framework about teacher effectiveness and student voice underpins the study. Findings indicate that suburban and…

  19. 7 CFR 4290.1500 - Restrictions on distributions to RBIC investors while RBIC has outstanding Leverage.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Restrictions on distributions to RBIC investors while... AGRICULTURE RURAL BUSINESS INVESTMENT COMPANY (âRBICâ) PROGRAM Financial Assistance for RBICs (Leverage) Distributions by Rbics with Outstanding Leverage § 4290.1500 Restrictions on distributions to RBIC...

  20. Excellence in Teaching Mathematics: Activities and Ideas from Ohio's Outstanding Teachers, 1994 District Winners.

    ERIC Educational Resources Information Center

    Borchers, Nancy, Ed.; Caniglia, Joanne, Ed.

    This document is a collection of lesson plans written by 18 of Ohio's outstanding teachers chosen by the Ohio Council of Teachers of Mathematics. Each lesson plan includes reflection questions and some contain worksheets. Lesson plan titles for primary grades (grades 1-3) are: "Munching Fractions;""Math and…

  1. [Diseases and causes of death of outstanding creative and scientific figures of XVII-XX centuries].

    PubMed

    Martsinkovs'kyĭ, I B

    2007-01-01

    The article reviewed the literature which analyzes clinical symptoms and causes of some creative and scientific figures of XVII-XX centuries. A conclusion has been made that there are not enough works with professional retrospective investigation of somatic diseases and causes of death of ukrainain outstanding cultural and scientific people in today's national medical literature.

  2. Getting It in Writing: The Quest to Become Outstanding and Effective Teachers of Writing

    ERIC Educational Resources Information Center

    Stankevich, Deborah M., Ed.

    2011-01-01

    Sixteen teachers. Sixteen journeys. All on a quest to become outstanding teachers of writing. All taking different paths to acquire and hone those skills that make a teacher effective. From kindergarten to college, teachers are faced with the daunting task of instilling the art of writing in their students. From creative writing to research, the…

  3. 7 CFR 4290.1500 - Restrictions on distributions to RBIC investors while RBIC has outstanding Leverage.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Restrictions on distributions to RBIC investors while...) Distributions by Rbics with Outstanding Leverage § 4290.1500 Restrictions on distributions to RBIC investors..., whenever you make a distribution to your investors you must make, at the same time, a prepayment to or...

  4. 7 CFR 4290.1500 - Restrictions on distributions to RBIC investors while RBIC has outstanding Leverage.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Restrictions on distributions to RBIC investors while...) Distributions by Rbics with Outstanding Leverage § 4290.1500 Restrictions on distributions to RBIC investors..., whenever you make a distribution to your investors you must make, at the same time, a prepayment to or...

  5. 7 CFR 4290.1500 - Restrictions on distributions to RBIC investors while RBIC has outstanding Leverage.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Restrictions on distributions to RBIC investors while...) Distributions by Rbics with Outstanding Leverage § 4290.1500 Restrictions on distributions to RBIC investors..., whenever you make a distribution to your investors you must make, at the same time, a prepayment to or...

  6. 7 CFR 4290.1500 - Restrictions on distributions to RBIC investors while RBIC has outstanding Leverage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Restrictions on distributions to RBIC investors while...) Distributions by Rbics with Outstanding Leverage § 4290.1500 Restrictions on distributions to RBIC investors..., whenever you make a distribution to your investors you must make, at the same time, a prepayment to or...

  7. Giving Back: Outstanding Alumni Stress the Importance of Community and Public Service

    ERIC Educational Resources Information Center

    Ullman, Ellen

    2010-01-01

    This article features several community college alumni who share how community colleges contributed to their success later in their lives and how they are inspired to give back. These outstanding alumni stress the importance of community and public service. They include: (1) Dr. Richard Carmona, U.S. Surgeon General from 2002 to 2006; (2) Colonel…

  8. Outstanding Science Trade Books for Students K-12: Books Published in 2002.

    ERIC Educational Resources Information Center

    Science and Children, 2003

    2003-01-01

    Provides a list of outstanding science trade books for elementary and secondary students published in 2002. Focuses on the areas of archaeology, anthropology, paleontology, biography, environment and ecology, life science, physical science, and science-related careers. Presents the selection criteria. (YDS)

  9. Outstanding Science Trade Books for Children--2001: Books Published in 2000.

    ERIC Educational Resources Information Center

    Science and Children, 2001

    2001-01-01

    Lists outstanding science trade books published in 2000. Explains the selection process and places the books into categories including: (1) Archaeology, Anthropology, and Paleontology; (2) Biography; (3) Earth and Space Science; (4) Environment and Ecology; (5) Life Science; (6) Physical Science; (7) Science-Related Careers; and (8) Technology and…

  10. The Secretary's Awards for Outstanding Vocational-Technical Education Programs. 1995.

    ERIC Educational Resources Information Center

    Office of Vocational and Adult Education (ED), Washington, DC.

    This publication describes the 12 winning programs and the 9 semifinalists of the 1995 U.S. Secretary of Education's Awards for Outstanding Vocational-Technical Education Programs. The awards program was established in 1981 to recognize excellence in local school-to-work and vocational-technical education programs, services, and activities that…

  11. 31 CFR 585.419 - Effect of E.O. 12846 on outstanding licenses and authorizations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Effect of E.O. 12846 on outstanding licenses and authorizations. 585.419 Section 585.419 Money and Finance: Treasury Regulations Relating to... AND HERZEGOVINA SANCTIONS REGULATIONS Interpretations § 585.419 Effect of E.O. 12846 on...

  12. Outstanding Science Trade Books for Students K-12 (Books Published in 2009)

    ERIC Educational Resources Information Center

    Science Teacher, 2010

    2010-01-01

    What makes an outstanding book for a young reader? Although it would be hard to create a rubric for every book, experienced teachers recognize them quickly. They fascinate and captivate with both their content and style. Award-winning trade books inspire young readers to want more... more information, more books, more inquiry, more science. The…

  13. A New "Picture of the World": The NCTE Orbis Pictus Award for Outstanding Nonfiction for Children.

    ERIC Educational Resources Information Center

    Vardell, Sylvia

    1991-01-01

    Provides information and discussion of the NCTE Orbis Pictus Award for Outstanding Nonfiction for Children. Explains what makes a good nonfiction book for children and discusses several books that have been honored in the first two years of the award. (MG)

  14. Performance Management or Managing Performance? Supporting a Vision to Become Outstanding

    ERIC Educational Resources Information Center

    Morton, Sam

    2011-01-01

    This paper provides an account of how performance management is operating in a rural primary school in the county of Rutland, UK, which aspires to provide an outstanding standard of education for its pupils. The paper begins by outlining the existing regulations for the operation of performance management in schools, before going on to explain how…

  15. Bioreactors Addressing Diabetes Mellitus

    PubMed Central

    Minteer, Danielle M.; Gerlach, Jorg C.

    2014-01-01

    The concept of bioreactors in biochemical engineering is a well-established process; however, the idea of applying bioreactor technology to biomedical and tissue engineering issues is relatively novel and has been rapidly accepted as a culture model. Tissue engineers have developed and adapted various types of bioreactors in which to culture many different cell types and therapies addressing several diseases, including diabetes mellitus types 1 and 2. With a rising world of bioreactor development and an ever increasing diagnosis rate of diabetes, this review aims to highlight bioreactor history and emerging bioreactor technologies used for diabetes-related cell culture and therapies. PMID:25160666

  16. Bioreactors addressing diabetes mellitus.

    PubMed

    Minteer, Danielle M; Gerlach, Jorg C; Marra, Kacey G

    2014-11-01

    The concept of bioreactors in biochemical engineering is a well-established process; however, the idea of applying bioreactor technology to biomedical and tissue engineering issues is relatively novel and has been rapidly accepted as a culture model. Tissue engineers have developed and adapted various types of bioreactors in which to culture many different cell types and therapies addressing several diseases, including diabetes mellitus types 1 and 2. With a rising world of bioreactor development and an ever increasing diagnosis rate of diabetes, this review aims to highlight bioreactor history and emerging bioreactor technologies used for diabetes-related cell culture and therapies.

  17. Content addressable memory project

    NASA Technical Reports Server (NTRS)

    Hall, J. Storrs; Levy, Saul; Smith, Donald E.; Miyake, Keith M.

    1992-01-01

    A parameterized version of the tree processor was designed and tested (by simulation). The leaf processor design is 90 percent complete. We expect to complete and test a combination of tree and leaf cell designs in the next period. Work is proceeding on algorithms for the computer aided manufacturing (CAM), and once the design is complete we will begin simulating algorithms for large problems. The following topics are covered: (1) the practical implementation of content addressable memory; (2) design of a LEAF cell for the Rutgers CAM architecture; (3) a circuit design tool user's manual; and (4) design and analysis of efficient hierarchical interconnection networks.

  18. On the nonlinear trapping nature of undamped, coherent structures in collisionless plasmas and its impact on stability

    NASA Astrophysics Data System (ADS)

    Schamel, Hans; Mandal, Debraj; Sharma, Devendra

    2017-03-01

    An outstanding notion for collisionless plasmas is the essential nonlinear character of their coherent structures, which in the stationary, weak amplitude limit are described by a continuum of cnoidal electron and ion hole modes governed by a multiparametric nonlinear dispersion relation. The well-known discrete structure of undamped linear plasma modes is seamlessly embedded in this nonlinear continuum as the microscopic texture of plasma begins to reveal itself in the high temperature collisionless plasma limit. This transforms the linear-threshold-based operating mechanism of plasma turbulence into a fundamental nonlinear, multifaceted one. Based on a comprehensive three-level description of increasing profundity, a proof of this novel dictum is presented, which makes use of the joint properties of such structures, their coherency and stationarity, and uses in succession a fluid, linear Vlasov and a full Vlasov description. It unifies discrete and continuum limits by resolving the inevitable resonant region and shows that coherent electrostatic equilibria are generally controlled by kinetic particle trapping and are hence fundamentally nonlinear. By forging a link between damped and growing wave solutions, these modes render plasma stability complex and difficult to evaluate due to the entangled pattern of the stability boundary in function and parameter space, respectively. A direct consequence is the existence of negative energy modes of arbitrarily small amplitudes in the subcritical region of the two-stream instability as well as the failure of linear Landau (Vlasov, van Kampen) theory, whenever resonant particles are involved, in addressing the onset of instability in a current-carrying plasma. Responsible for this subtle phase space behavior is hence the thresholdless omnipresence of the trapping nonlinearity originating from coherency. A high resolution, exact-mass-ratio, multispecies, and collisionless plasma simulation is employed to illustrate

  19. Addressing Environmental Health Inequalities

    PubMed Central

    Gouveia, Nelson

    2016-01-01

    Environmental health inequalities refer to health hazards disproportionately or unfairly distributed among the most vulnerable social groups, which are generally the most discriminated, poor populations and minorities affected by environmental risks. Although it has been known for a long time that health and disease are socially determined, only recently has this idea been incorporated into the conceptual and practical framework for the formulation of policies and strategies regarding health. In this Special Issue of the International Journal of Environmental Research and Public Health (IJERPH), “Addressing Environmental Health Inequalities—Proceedings from the ISEE Conference 2015”, we incorporate nine papers that were presented at the 27th Conference of the International Society for Environmental Epidemiology (ISEE), held in Sao Paulo, Brazil, in 2015. This small collection of articles provides a brief overview of the different aspects of this topic. Addressing environmental health inequalities is important for the transformation of our reality and for changing the actual development model towards more just, democratic, and sustainable societies driven by another form of relationship between nature, economy, science, and politics. PMID:27618906

  20. Content addressable memory project

    NASA Technical Reports Server (NTRS)

    Hall, Josh; Levy, Saul; Smith, D.; Wei, S.; Miyake, K.; Murdocca, M.

    1991-01-01

    The progress on the Rutgers CAM (Content Addressable Memory) Project is described. The overall design of the system is completed at the architectural level and described. The machine is composed of two kinds of cells: (1) the CAM cells which include both memory and processor, and support local processing within each cell; and (2) the tree cells, which have smaller instruction set, and provide global processing over the CAM cells. A parameterized design of the basic CAM cell is completed. Progress was made on the final specification of the CPS. The machine architecture was driven by the design of algorithms whose requirements are reflected in the resulted instruction set(s). A few of these algorithms are described.

  1. Nonlinear optomechanical measurement of mechanical motion

    PubMed Central

    Brawley, G. A.; Vanner, M. R.; Larsen, P. E.; Schmid, S.; Boisen, A.; Bowen, W. P.

    2016-01-01

    Precision measurement of nonlinear observables is an important goal in all facets of quantum optics. This allows measurement-based non-classical state preparation, which has been applied to great success in various physical systems, and provides a route for quantum information processing with otherwise linear interactions. In cavity optomechanics much progress has been made using linear interactions and measurement, but observation of nonlinear mechanical degrees-of-freedom remains outstanding. Here we report the observation of displacement-squared thermal motion of a micro-mechanical resonator by exploiting the intrinsic nonlinearity of the radiation-pressure interaction. Using this measurement we generate bimodal mechanical states of motion with separations and feature sizes well below 100 pm. Future improvements to this approach will allow the preparation of quantum superposition states, which can be used to experimentally explore collapse models of the wavefunction and the potential for mechanical-resonator-based quantum information and metrology applications. PMID:26996234

  2. [Keynote address: Climate change

    SciTech Connect

    Forrister, D.

    1994-12-31

    Broadly speaking, the climate issue is moving from talk to action both in the United States and internationally. While few nations have adopted strict controls or stiff new taxes, a number of them are developing action plans that are making clear their intention to ramp up activity between now and the year 2000... and beyond. There are sensible, economically efficient strategies to be undertaken in the near term that offer the possibility, in many countries, to avoid more draconian measures. These strategies are by-and-large the same measures that the National Academy of Sciences recommended in a 1991 report called, Policy Implications of Greenhouse Warming. The author thinks the Academy`s most important policy contribution was how it recommended the nations act in the face of uncertain science and high risks--that cost effective measures are adopted as cheap insurance... just as nations insure against other high risk, low certainty possibilities, like catastrophic health insurance, auto insurance, and fire insurance. This insurance theme is still right. First, the author addresses how the international climate change negotiations are beginning to produce insurance measures. Next, the author will discuss some of the key issues to watch in those negotiations that relate to longer-term insurance. And finally, the author will report on progress in the United States on the climate insurance plan--The President`s Climate Action Plan.

  3. Two Outstanding Investigator Awards Go to Division of Cancer Prevention Grantees | Division of Cancer Prevention

    Cancer.gov

    NCI's Outstanding Investigator Award supports accomplished leaders in cancer research, who are providing significant contributions toward understanding cancer and developing applications that may lead to a breakthrough in biomedical, behavioral, or clinical cancer research. The Award provides up to $600,000 in direct costs per year for 7 years, allowing substantial time for funded investigators to take greater risks and be more adventurous in their research. Two of these awards have been made to Division of Cancer Prevention investigators: |

  4. A comparison of teacher and principal perception of an outstanding biology teacher

    NASA Astrophysics Data System (ADS)

    Searles, William E.; Ng, Raymond W. M.

    The purpose of this study was to ascertain the level of agreement or disagreement between principals and teachers when using established criteria to measure the effectiveness of a biology teacher. To obtain information regarding their perceptions of an outstanding biology teacher, twenty-two principals and forty-one biology teachers were chosen randomly from English-speaking high schools within a 50 km radius of metropolitan Montreal, Quebec, Canada. The measuring instrument was a modified version of Dieter's questionnaire that evolved from his doctoral study of the National Association of Biology Teachers-Outstanding Biology Teacher Award Program. The data collected from the two populations were tested using one-way ANOVA (analysis of variance) or by applying normal approximation. Results indicated that both the principals and teachers agree on the relative importance of most criteria, particularly those related to the teacher's classroom behavior and academic background in biology. From such results, it was possible to construct one stereotype of the outstanding biology teacher. A number of recommendations were made from the results of the study, which were directed to the (a) teachers and their professional organization, (b) principals and the school boards, (c) teacher training institutions, and (d) researchers in teacher evaluation.

  5. Defining core elements and outstanding practice in Nutritional Science through collaborative benchmarking.

    PubMed

    Samman, Samir; McCarthur, Jennifer O; Peat, Mary

    2006-01-01

    Benchmarking has been adopted by educational institutions as a potentially sensitive tool for improving learning and teaching. To date there has been limited application of benchmarking methodology in the Discipline of Nutritional Science. The aim of this survey was to define core elements and outstanding practice in Nutritional Science through collaborative benchmarking. Questionnaires that aimed to establish proposed core elements for Nutritional Science, and inquired about definitions of " good" and " outstanding" practice were posted to named representatives at eight Australian universities. Seven respondents identified core elements that included knowledge of nutrient metabolism and requirement, food production and processing, modern biomedical techniques that could be applied to understanding nutrition, and social and environmental issues as related to Nutritional Science. Four of the eight institutions who agreed to participate in the present survey identified the integration of teaching with research as an indicator of outstanding practice. Nutritional Science is a rapidly evolving discipline. Further and more comprehensive surveys are required to consolidate and update the definition of the discipline, and to identify the optimal way of teaching it. Global ideas and specific regional requirements also need to be considered.

  6. Nonlinear channelizer.

    PubMed

    In, Visarath; Longhini, Patrick; Kho, Andy; Neff, Joseph D; Leung, Daniel; Liu, Norman; Meadows, Brian K; Gordon, Frank; Bulsara, Adi R; Palacios, Antonio

    2012-12-01

    The nonlinear channelizer is an integrated circuit made up of large parallel arrays of analog nonlinear oscillators, which, collectively, serve as a broad-spectrum analyzer with the ability to receive complex signals containing multiple frequencies and instantaneously lock-on or respond to a received signal in a few oscillation cycles. The concept is based on the generation of internal oscillations in coupled nonlinear systems that do not normally oscillate in the absence of coupling. In particular, the system consists of unidirectionally coupled bistable nonlinear elements, where the frequency and other dynamical characteristics of the emergent oscillations depend on the system's internal parameters and the received signal. These properties and characteristics are being employed to develop a system capable of locking onto any arbitrary input radio frequency signal. The system is efficient by eliminating the need for high-speed, high-accuracy analog-to-digital converters, and compact by making use of nonlinear coupled systems to act as a channelizer (frequency binning and channeling), a low noise amplifier, and a frequency down-converter in a single step which, in turn, will reduce the size, weight, power, and cost of the entire communication system. This paper covers the theory, numerical simulations, and some engineering details that validate the concept at the frequency band of 1-4 GHz.

  7. Nonlinearity effects on the directed momentum current.

    PubMed

    Zhao, Wen-Lei; Fu, Li-Bin; Liu, Jie

    2014-08-01

    We investigate the quantum transport dynamics governed by the nonlinear Schrödinger equation with a periodically-δ-kicking potential and discover the emergence of a directed current in momentum space. With the increase of nonlinearity, we find strikingly that the momentum current decreases, reverses, and finally vanishes, indicating that the quantum transport can be effectively manipulated through adjusting the nonlinearity. The underlying dynamic mechanism is uncovered and some important implications are addressed.

  8. Nonlinear Systems.

    ERIC Educational Resources Information Center

    Seider, Warren D.; Ungar, Lyle H.

    1987-01-01

    Describes a course in nonlinear mathematics courses offered at the University of Pennsylvania which provides an opportunity for students to examine the complex solution spaces that chemical engineers encounter. Topics include modeling many chemical processes, especially those involving reaction and diffusion, auto catalytic reactions, phase…

  9. Nonlinear Acoustics

    DTIC Science & Technology

    1974-02-14

    Wester- velt. [60] Streaming. In 1831, Michael Faraday [61] noted that currents of air were set up in the neighborhood of vibrating plates-the first... ducei in the case of a paramettc amy (from Berktay an Leahy 141). C’ "". k•, SEC 10.1 NONLINEAR ACOUSTICS 345 The principal results of their analysis

  10. Nonlinear resonance

    NASA Astrophysics Data System (ADS)

    Kevorkian, J.

    This report discusses research in the area of slowly varying nonlinear oscillatory systems. Some of the topics discussed are as follows: adiabatic invariants and transient resonance in very slowly varying Hamiltonian systems; sustained resonance in very slowly varying Hamiltonian systems; free-electron lasers with very slow wiggler taper; and bursting oscillators.

  11. The Surface of Venus and Implications for its Geological and Geodynamical Evolution: The View Before Venus Express and Outstanding Questions for the Future

    NASA Astrophysics Data System (ADS)

    Head, J. W.; Ivanov, M. A.; Basilevsky, A. T.

    2008-12-01

    thickness variations and mantle convection patterns. The relationships of major elements of global topography and the sequence of events in the observed geological history (as recorded by major geologic units and structures) suggest that much of the current long-wavelength topography of Venus (tessera highlands and lowlands with regional plains) may have formed prior to emplacement of regional plains and been preserved since that time. These observations may favor evolutionary geodynamic models that are characterized by changes in geological style and rates, and may involve non-linear heat loss mechanisms that could have profound influence on the atmosphere. Although the observed surface of Venus dates from relatively recent planetary history, comparative planetology permits inferences to be made about the major stages in the earlier history of Venus. The evolution of the understanding of the surface from early speculations to present observations and interpretations provides an important context for: 1) establishing the relationships of the surface of Venus to the nature of the atmosphere and its evolution as assessed by Venus Express, 2) the comparison of the geological features and history of Venus relative to the Moon, Mars, Mercury and the Earth, and 3) defining the major outstanding problems and questions to be addressed by future experiments and missions to Venus.

  12. The Reach Address Database (RAD)

    EPA Pesticide Factsheets

    The Reach Address Database (RAD) stores reach address information for each Water Program feature that has been linked to the underlying surface water features (streams, lakes, etc) in the National Hydrology Database (NHD) Plus dataset.

  13. Outstanding Research Issues in Systematic Technology Prioritization for New Space Missions: Workshop Proceedings

    NASA Technical Reports Server (NTRS)

    Weisbin, C. R. (Editor)

    2004-01-01

    A workshop entitled, "Outstanding Research Issues in Systematic Technology Prioritization for New Space Missions," was convened on April 21-22, 2004 in San Diego, California to review the status of methods for objective resource allocation, to discuss the research barriers remaining, and to formulate recommendations for future development and application. The workshop explored the state-of-the-art in decision analysis in the context of being able to objectively allocate constrained technical resources to enable future space missions and optimize science return. This article summarizes the highlights of the meeting results.

  14. EDITORIAL: Announcing the 2009 Measurement Science and Technology Outstanding Paper Awards Announcing the 2009 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Fujii, Kenichi; Regtien, Paul

    2010-06-01

    Since 1991, Measurement Science and Technology has awarded a Best Paper prize. The Editorial Board of this journal believes that such a prize is an opportunity to thank authors for submitting their work, and serves as an integral part of the on-going quality review of the journal. The current breadth of topical areas that are covered by MST has made it advisable to expand the recognition of excellent publications. Hence, since 2005 the Editorial Board have presented 'Outstanding Paper Awards' in four subject categories: Fluid Mechanics; Measurement Science; Precision Measurements; and Sensors and Sensing Systems. This year also saw the introduction of a new category—Optical and Laser-based Techniques. 2009 Award Winners—Fluid Mechanics Digital particle image velocimetry (DPIV) robust phase correlation Adric Eckstein and Pavlos P Vlachos Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA, USA This paper [1] represents a valuable improvement to the phase-only correlation technique (first proposed by Wernet in this journal in 2005 (Wernet M 2005 Symmetric phase-only filtering: a new paradigm for DPIV data processing Meas. Sci. Technol. 16 601-18) for particle-image-velocimetry (PIV) measurements of fluid flow. The authors establish a sound theoretical foundation and clearly describe the working principle of their robust phase correlation method. The methodology for assessing performance is excellent. Detailed results on several internationally recognized PIV test cases are presented. The robust phase correlation method is of general applicability and therefore can be expected to have substantial impact in this very active area of fluid-mechanics measurements. 2009 Award Winner—Precision Measurement A nanonewton force facility and a novel method for measurements of the air and vacuum permittivity at zero frequencies V Nesterov Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, D-38116 Braunschweig, Germany This paper [2] describes a

  15. Dark energy simulacrum in nonlinear electrodynamics

    SciTech Connect

    Labun, Lance; Rafelski, Johann

    2010-03-15

    Quasiconstant external fields in nonlinear electromagnetism generate a global contribution proportional to g{sup {mu}{nu}}in the energy-momentum tensor, thus a simulacrum of dark energy. To provide a thorough understanding of the origin and strength of its effects, we undertake a complete theoretical and numerical study of the energy-momentum tensor T{sup {mu}{nu}}for nonlinear electromagnetism. The Euler-Heisenberg nonlinearity due to quantum fluctuations of spinor and scalar matter fields is considered and contrasted with the properties of classical nonlinear Born-Infeld electromagnetism. We address modifications of charged particle kinematics by strong background fields.

  16. Celebration of DOE's 35th Anniversary and the Secretary of Energy's Honor Awards, Keynote Address: Energy Secretary, Dr. Steven Chu

    ScienceCinema

    Chu, Steven (U.S. Energy Secretary)

    2016-07-12

    Dr. Steven Chu gives a keynote address marking the thirty-fifth anniversary of the Department of Energy (DOE). He highlights outstanding achievements of the Department and its scientists. Several of the Department's many Nobel Prize winners over the years are mentioned.

  17. Solving multistage stochastic programming models of portfolio selection with outstanding liabilities

    SciTech Connect

    Edirisinghe, C.

    1994-12-31

    Models for portfolio selection in the presence of an outstanding liability have received significant attention, for example, models for pricing options. The problem may be described briefly as follows: given a set of risky securities (and a riskless security such as a bond), and given a set of cash flows, i.e., outstanding liability, to be met at some future date, determine an initial portfolio and a dynamic trading strategy for the underlying securities such that the initial cost of the portfolio is within a prescribed wealth level and the expected cash surpluses arising from trading is maximized. While the trading strategy should be self-financing, there may also be other restrictions such as leverage and short-sale constraints. Usually the treatment is limited to binomial evolution of uncertainty (of stock price), with possible extensions for developing computational bounds for multinomial generalizations. Posing as stochastic programming models of decision making, we investigate alternative efficient solution procedures under continuous evolution of uncertainty, for discrete time economies. We point out an important moment problem arising in the portfolio selection problem, the solution (or bounds) on which provides the basis for developing efficient computational algorithms. While the underlying stochastic program may be computationally tedious even for a modest number of trading opportunities (i.e., time periods), the derived algorithms may used to solve problems whose sizes are beyond those considered within stochastic optimization.

  18. Sourcing Program: To identify outstanding women and ethnic minorities in research and research management

    SciTech Connect

    Nissen, S.H.

    1991-08-01

    To meet the challenges of the changing demographics and a projected shortage of technically trained workers in the 21st century, Lawrence Livermore National (LLNL) is increasing its commitment to develop a diverse work force with the abilities to carry out the Laboratory's missions. In addition to the recruitment programs already established at LLNL, a sourcing program to identify outstanding women and minorities in research and research management was initiated in the summer of 1990. A research methodology, time table, selection criteria, and data generation strategy were designed and implemented for this program. Through extensive contacts with R D facilities, women's and minority professional organizations, national research councils, technical professional societies and universities, other sourcing programs were investigated and evaluated and a network of contacts and resources was developed. This report describes the design and implementation of the sourcing program targeting outstanding women and minorities in science and engineering. It details the investigation and evaluation of sourcing programs in other R D facilities and provides information regarding methods and sources used to identify potential candidates. Conclusions and recommendations are presented. 10 refs., 5 tabs.

  19. A novel poly(acrylic acid-co-acrylamide)/diatomite composite flocculant with outstanding flocculation performance.

    PubMed

    Xu, Kun; Liu, Yao; Wang, Yang; Tan, Ying; Liang, Xuecheng; Lu, Cuige; Wang, Haiwei; Liu, Xiusheng; Wang, Pixin

    2015-01-01

    Series of anionic flocculants with outstanding flocculation performance, poly(acrylic acid-co-acrylamide)/diatomite composite flocculants (PAAD) were successfully prepared through aqueous solution copolymerization and applied to flocculate from oil-field fracturing waste-water. The structure of PAAD was characterized by Fourier transform infra-red spectroscopy, (13)C nuclear magnetic resonance and X-ray diffraction tests, and its properties were systematically evaluated by viscometer, thermogravimetry analysis and flocculation measurements. Furthermore, the influences of various reaction parameters on the apparent viscosity of flocculant solution were studied, and the optimum synthesis condition was determined. The novel composite flocculants exhibited outstanding flocculation properties. Specifically, the dosage of composite flocculants that could make the transmittance of treated wastewater exceed 90% was only approximately 12-35 ppm, which was far lower than that of conventional flocculants. Meanwhile, the settling time was lower than 5 s, which was similar to that of conventional flocculants. This was because PAAD flocculants had a higher absorption capacity, and larger chain extending space than conventional linear flocculants, which could refrain from the entanglement of linear polymer chains and significantly improve flocculation capacity.

  20. Highly Non-Linear Optical (NLO) organic crystals and films. Electrooptical organic materials

    NASA Technical Reports Server (NTRS)

    Mcmanus, Samuel P.; Rosenberger, Franz; Matthews, John

    1987-01-01

    Devices employing nonlinear optics (NLO) hold great promise for important applications in integrated optics, optical information processing and telecommunications. Properly designed organics possess outstanding optical and electrooptical properties which will substantially advance many technologies including electrooptical switching, optical amplification for communications, and parallel processing for hybrid optical computers. A brief comparison of organic and inorganic materials is given.

  1. CONTENT-ADDRESSABLE MEMORY SYSTEMS,

    DTIC Science & Technology

    The utility of content -addressable memories (CAM’s) within a general purpose computing system is investigated. Word cells within CAM may be...addressed by the character of all or a part of cell contents . Multimembered sets of word cells may be addressed simultaneously. The distributed logical...package is developed which allows simulation of CAM commands within job programs run on the IBM 7090 and derives tallies of execution times corresponding to a particular realization of a CAM system . (Author)

  2. Outstanding Questions In First Amendment Law Related To Food Labeling Disclosure Requirements For Health.

    PubMed

    Pomeranz, Jennifer L

    2015-11-01

    The federal and state governments are increasingly focusing on food labeling as a method to support good health. Many such laws are opposed by the food industry and may be challenged in court, raising the question of what is legally feasible. This article analyzes outstanding questions in First Amendment law related to commercial disclosure requirements and conducts legal analysis and policy evaluation for three current policies. These include the Food and Drug Administration's draft regulation requiring an added sugar disclosure on the Nutrition Facts panel, California's proposed sugar-sweetened beverage safety warning label bill, and Vermont's law requiring labels of genetically engineered food to disclose this information. I recommend several methods for policy makers to enact food labeling laws within First Amendment parameters, including imposing factual commercial disclosure requirements, disclosing the government entity issuing a warning, collecting evidence, and identifying legitimate governmental interests.

  3. [The outstanding figure of domestic military and civil public health services].

    PubMed

    Pavlovskiĭ, L N

    2011-01-01

    The article presents data on the outstanding Soviet theorist and the organizer of Health Care, full member of Academy of Medical Science of the U.S.S.R., the Hero of Socialist Work, the colonel general of a health service E.I. Smirnov who has developed a lot on the theory and practice of civil and military public health services. Its contribution to communication between organizational forms of medical maintenance of armies and principles of military art, and also dependence of quality of medical aid to the population on the organizational structure of a treatment-and-prophylactic network were considered. E.I. Smirnova's personal role in improvement of organizational forms of medical maintenance of armies, theory and practice development of intermediate treatments with evacuation to destination, in the organization of antiepidemic maintenance of armies and development number of actual questions of modern military medicine are shown in the article.

  4. Graphene with outstanding anti-irradiation capacity as multialkylated cyclopentanes additive toward space application

    PubMed Central

    Fan, Xiaoqiang; Wang, Liping

    2015-01-01

    Multialkylated cyclopentanes (MACs), a class of synthetic hydrocarbon fluid have attracted intensive interest as possible space lubricants due to a series of unique physical and chemical properties. Here, we used graphene with high mechanical strength and chemical inertness as lubricant additive to explore its potential for space application. The effects of space irradiation on graphene and the tribological properties of graphene as lubricant additive were firstly investigated in detail under simulated space environment composed of high vacuum, high/low temperature and irradiation. Results demonstrate that graphene not only possesses outstanding anti–irradiation capacity but also significantly improves the space performance and tribological properties of MACs, which depends on the excellent physicochemical properties and high load-carrying ability of graphene as well as more effective separation of the sliding surfaces. PMID:26224254

  5. Outstanding conference paper award 2014 IEEE nuclear and space radiation effects conference

    SciTech Connect

    Dodds, Nathaniel Anson; Schwank, James R.; Shaneyfelt, Marty R.; Dodd, Paul E.; Doyle, Barney Lee; Trinczek, Michael; Blackmore, Ewart W.; Rodbell, Kenneth P.; Reed, Robert A.; Pellish, Jonathan A.; LaBel, Kenneth A.; Marshall, Paul W.; Swanson, Scot E.; Vizkelethy, Gyorgy; Van Deusen, Stuart B.; Sexton, Frederick W.; Martinez, Marino John

    2014-12-01

    The recipients of the 2014 NSREC Outstanding Conference Paper Award are Nathaniel A. Dodds, James R. Schwank, Marty R. Shaneyfelt, Paul E. Dodd, Barney L. Doyle, Michael Trinczek, Ewart W. Blackmore, Kenneth P. Rodbell, Michael S. Gordon, Robert A. Reed, Jonathan A. Pellish, Kenneth A. LaBel, Paul W. Marshall, Scot E. Swanson, Gyorgy Vizkelethy, Stuart Van Deusen, Frederick W. Sexton, and M. John Martinez, for their paper entitled "Hardness Assurance for Proton Direct Ionization-Induced SEEs Using a High-Energy Proton Beam." For older CMOS technologies, protons could only cause single-event effects (SEEs) through nuclear interactions. Numerous recent studies on 90 nm and newer CMOS technologies have shown that protons can also cause SEEs through direct ionization. Furthermore, this paper develops and demonstrates an accurate and practical method for predicting the error rate caused by proton direct ionization (PDI).

  6. Outstanding visible photocatalytic activity of a new mixed bismuth titanatate material

    NASA Astrophysics Data System (ADS)

    Zambrano, P.; Sayagués, M. J.; Navío, J. A.; Hidalgo, M. C.

    2017-02-01

    In this work, a new photocatalyst based on bismuth titanates with outstanding visible photocatalytic activity was prepared by a facile hydrothermal method. The synthesised material showed visible activity as high as UV activity of commercial TiO2 P25 under the same experimental conditions for phenol degradation. A wide characterisation of the photocatalyst was performed. The material was composed of three phases; majority of Bi20TiO32 closely interconnected to Bi4Ti3O12 and amorphous TiO2. The high visible activity showed by this material could be ascribed to a combination of several features; i.e. low band gap energy value (2.1 eV), a structure allowing a good separation path for visible photogenerated electron-holes pairs and a relatively high surface area. This photocatalyst appeared as a promising material for solar and visible applications of photocatalysis.

  7. Outstanding conference paper award 2014 IEEE nuclear and space radiation effects conference

    DOE PAGES

    Dodds, Nathaniel Anson; Schwank, James R.; Shaneyfelt, Marty R.; ...

    2014-12-01

    The recipients of the 2014 NSREC Outstanding Conference Paper Award are Nathaniel A. Dodds, James R. Schwank, Marty R. Shaneyfelt, Paul E. Dodd, Barney L. Doyle, Michael Trinczek, Ewart W. Blackmore, Kenneth P. Rodbell, Michael S. Gordon, Robert A. Reed, Jonathan A. Pellish, Kenneth A. LaBel, Paul W. Marshall, Scot E. Swanson, Gyorgy Vizkelethy, Stuart Van Deusen, Frederick W. Sexton, and M. John Martinez, for their paper entitled "Hardness Assurance for Proton Direct Ionization-Induced SEEs Using a High-Energy Proton Beam." For older CMOS technologies, protons could only cause single-event effects (SEEs) through nuclear interactions. Numerous recent studies on 90 nmmore » and newer CMOS technologies have shown that protons can also cause SEEs through direct ionization. Furthermore, this paper develops and demonstrates an accurate and practical method for predicting the error rate caused by proton direct ionization (PDI).« less

  8. Inherently Chiral Macrocyclic Oligothiophenes: Easily Accessible Electrosensitive Cavities with Outstanding Enantioselection Performances

    PubMed Central

    Sannicolò, Francesco; Mussini, Patrizia R; Benincori, Tiziana; Cirilli, Roberto; Abbate, Sergio; Arnaboldi, Serena; Casolo, Simone; Castiglioni, Ettore; Longhi, Giovanna; Martinazzo, Rocco; Panigati, Monica; Pappini, Marco; Quartapelle Procopio, Elsa; Rizzo, Simona

    2014-01-01

    Linear conjugated oligothiophenes of variable length and different substitution pattern are ubiquitous in technologically advanced optoelectronic devices, though limitations in application derive from insolubility, scarce processability and chain-end effects. This study describes an easy access to chiral cyclic oligothiophenes constituted by 12 and 18 fully conjugated thiophene units. Chemical oxidation of an “inherently chiral” sexithiophene monomer, synthesized in two steps from commercially available materials, induces the formation of an elliptical dimer and a triangular trimer endowed with electrosensitive cavities of different tunable sizes. Combination of chirality with electroactivity makes these molecules unique in the current oligothiophenes literature. These macrocycles, which are stable and soluble in most organic solvents, show outstanding chiroptical properties, high circularly polarized luminescence effects and an exceptional enantiorecognition ability. PMID:25263106

  9. Address tracing for parallel machines

    NASA Technical Reports Server (NTRS)

    Stunkel, Craig B.; Janssens, Bob; Fuchs, W. Kent

    1991-01-01

    Recently implemented parallel system address-tracing methods based on several metrics are surveyed. The issues specific to collection of traces for both shared and distributed memory parallel computers are highlighted. Five general categories of address-trace collection methods are examined: hardware-captured, interrupt-based, simulation-based, altered microcode-based, and instrumented program-based traces. The problems unique to shared memory and distributed memory multiprocessors are examined separately.

  10. EDITORIAL: Announcing the 2011 Measurement Science and Technology Outstanding Paper Awards Announcing the 2011 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Fujii, Kenichi; Regtien, Paul; Tatam, Ralph

    2012-06-01

    Since 1991, Measurement Science and Technology has awarded a Best Paper prize. The Editorial Board of this journal believe that such a prize is an opportunity to thank authors for submitting their work, and serves as an integral part of the on-going quality review of the journal. The current breadth of topical areas that are covered by MST has made it advisable to expand the recognition of excellent publications. Hence, since 2005 the Editorial Board have presented 'Outstanding Paper Awards'. This year awards were presented in the areas of 'Measurement Science', 'Fluid Mechanics' and 'Precision Measurement'. Although the categories mirror subject sections in the journal, the Editorial Board consider articles from all categories in the selection process. 2011 Award Winners—Measurement Science Simultaneous measurement of internal and surrounding flows of a moving droplet using multicolour confocal micro-particle image velocimetry (micro-PIV) M Oishi, H Kinoshita, T Fujii and M Oshima Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-Ku, Tokyo 153-8505, Japan Interfaculty Initiative in Information Studies, The University of Tokyo, 4-6-1 Komaba, Meguro-Ku, Tokyo 153-8505, Japan Whilst the award last year [1] was concerned with the application of microscopy to ultra-high vacuum dynamic force measurements, this year's award [2] goes to another micro-measurement technique, one concerned with measurements related to particle image velocimetry. The technique relates to multiphase flow in microfluidic devices, and offers a non-contact methodology for examining simultaneous dynamic interactions between flows having different phases. There are several features which make this an excellent paper. It introduces its subject with a clear and concise description of previous advances in related measurement methods, before introducing the additional feature of two-colour fluorescent monitoring of flow in two independent optical channels. By adapting a

  11. New Nonlinear Multigrid Analysis

    NASA Technical Reports Server (NTRS)

    Xie, Dexuan

    1996-01-01

    The nonlinear multigrid is an efficient algorithm for solving the system of nonlinear equations arising from the numerical discretization of nonlinear elliptic boundary problems. In this paper, we present a new nonlinear multigrid analysis as an extension of the linear multigrid theory presented by Bramble. In particular, we prove the convergence of the nonlinear V-cycle method for a class of mildly nonlinear second order elliptic boundary value problems which do not have full elliptic regularity.

  12. Nonlinear Observers for Gyro Calibration

    NASA Technical Reports Server (NTRS)

    Thienel, Julie; Sanner, Robert M.

    2003-01-01

    High precision estimation and control algorithms, to achieve unprecedented levels of pointing accuracy, will be required to support future formation flying missions such as interferometry missions. Achieving high pointing accuracy requires precise knowledge of the spacecraft rotation rate. Typically, the rotation rate is measured by a gyro. The measured rates can be corrupted by errors in alignment and scale factor, gyro biases, and noise. In this work, we present nonlinear observers for gyro calibration. Nonlinear observers are superior to extended or pseudo-linear Kalman filter type approaches for large errors and global stability. Three nonlinear gyro calibration observers are developed. The first observer estimates a constant gyro bias. The second observer estimates scale factor errors. The third observer estimates the gyro alignment for three orthogonal gyros. The convergence properties of all three observers are discussed. Additionally, all three observers are coupled with a nonlinear control algorithm. The stability of each of the resulting closed loop systems is analyzed. The observers are then combined, and the gyro calibration parameters are estimated simultaneously. The stability of the combined observers is addressed, as well as the stability of the resulting closed loop systems. Simulated test results are presented for each scenario. Finally, the nonlinear observers are compared to a pseudo-linear Kalman filter.

  13. Physics, Nonlinear Time Series Analysis, Data Assimilation and Hyperfast Modeling of Nonlinear Ocean Waves

    DTIC Science & Technology

    2010-09-30

    Hyperfast Modeling of Nonlinear Ocean Waves A. R. Osborne Dipartimento di Fisica Generale, Università di Torino Via Pietro Giuria 1, 10125...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Universit?i Torino,Dipartimento di Fisica Generale,Via Pietro Giuria 1,10125 Torino, Italy, 8. PERFORMING

  14. Improved nonlinear prediction method

    NASA Astrophysics Data System (ADS)

    Adenan, Nur Hamiza; Md Noorani, Mohd Salmi

    2014-06-01

    The analysis and prediction of time series data have been addressed by researchers. Many techniques have been developed to be applied in various areas, such as weather forecasting, financial markets and hydrological phenomena involving data that are contaminated by noise. Therefore, various techniques to improve the method have been introduced to analyze and predict time series data. In respect of the importance of analysis and the accuracy of the prediction result, a study was undertaken to test the effectiveness of the improved nonlinear prediction method for data that contain noise. The improved nonlinear prediction method involves the formation of composite serial data based on the successive differences of the time series. Then, the phase space reconstruction was performed on the composite data (one-dimensional) to reconstruct a number of space dimensions. Finally the local linear approximation method was employed to make a prediction based on the phase space. This improved method was tested with data series Logistics that contain 0%, 5%, 10%, 20% and 30% of noise. The results show that by using the improved method, the predictions were found to be in close agreement with the observed ones. The correlation coefficient was close to one when the improved method was applied on data with up to 10% noise. Thus, an improvement to analyze data with noise without involving any noise reduction method was introduced to predict the time series data.

  15. Outstanding in the Field II: Citizen Science Experiences for Middle Schools in Northeast Louisiana

    NASA Astrophysics Data System (ADS)

    Case Hanks, A. T.; Bhattacharjee, J.; Clark, L.; Pugh, A.

    2012-12-01

    In order to prepare middle school teachers for the next generation sciences standards and the new common core, the University of Louisiana at Monroe (ULM) Colleges of Arts and Sciences and Education and Human Development launched the Outstanding in the Field II program. Through the creation of a mesonet with the weather stations at middle school sites, this project aims to foster and enrich the experience of teacher/student-collected data while logging the data into a larger scientific database, producing citizen scientists. By empowering students and teachers to actively participate in 'real science', they generate data to be analyzed from both the physical and life science perspective and thus, highlight the next generation science standards and core disciplinary ideas. This project also promotes collaboration between the life and physical sciences while highlighting scientific practices and cross-cutting concepts within science and literacy. To ensure the successful implementation of the program, faculty and will provide several follow-up workshops during the academic year. These workshops will focus on the common core connections of math and literacy as well as ways in which the project can be supported at each site through face-to-face observations and online collaborations. This year-long program began with a field intensive workshop in July 2012 and enrolled 30 6th, 7th, and 8th science teachers from the Northeast region of Louisiana to provide a genuine scientific experience that would be taken back and applied within the classroom. By becoming students, teachers began by collecting data in the field and establishing and refining the intricate connection between real- world experiments and science taught in classrooms. . They returned to the ULM campus to build and deploy weather stations. Teachers were then tasked with the development of a plan to install the weather station and collect data at their school site with emphasis on implementation within their

  16. Nonlinear Waves.

    DTIC Science & Technology

    1986-05-27

    con- €"" straints:’. *’Permanent address: Dipartimento di Fisica . Universita di Roma 1. 00185 u 11lia. tr(a U(x)) = 0. (7a. 2469 1. Math,. PyS. 26 (10...Tenenblat Universidade de Brasilia Departamento de Matematica Brasilia, Brasil September 1985 , - . Abstract The generalized wave equation and generalized...Permanent addrems: Dipartimento di Fisica . Universita di Roma t3 U, 0. Roma. Italy The linear limit of i3) provides the most general solution ot 2614 J. MatM

  17. EDITORIAL: Announcing the 2010 Measurement Science and Technology Outstanding Paper Awards Announcing the 2010 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Fujii, Kenichi; Regtien, Paul

    2011-06-01

    Since 1991, Measurement Science and Technology has awarded a Best Paper prize. The Editorial Board of this journal believes that such a prize is an opportunity to thank authors for submitting their work, and serves as an integral part of the on-going quality review of the journal. The current breadth of topical areas that are covered by MST has made it advisable to expand the recognition of excellent publications. Hence, since 2005 the Editorial Board have presented 'Outstanding Paper Awards' in four subject categories: Fluid Mechanics; Measurement Science; Precision Measurements; and Sensors and Sensing Systems. Although the categories mirror subject sections in the journal, the Editorial Board consider articles from all categories in the selection process. This year, for example, the winning article of the Outstanding Paper Award in Sensors and Sensing Systems was an article published in the 'Novel Instrumentation' section. 2010 Award Winners—Fluid Mechanics Assessment of pressure field calculations from particle image velocimetry measurements John J Charonko, Cameron V King, Barton L Smith and Pavlos P Vlachos Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24060, USA VT-WFU School of Biomedical Engineering & Sciences, Virginia Tech, Blacksburg, VA 24060, USA Mechanical and Aerospace Engineering Department, Utah State University, UMC4130, Logan, UT 84322, USA Measuring p(t) in the interior of a flow field is one of the most challenging measurements in our field of study. An accurate knowledge of these interior pressures is of considerable value for fundamental studies. Since the gradient of the pressure appears in the Navier-Stokes equations, a knowledge of the pressure at a bounding surface followed by operations on the measured velocity components within the flow field can be analytically related to the pressure at an interior location. Bringing this long-recognized possibility to operational status has been greatly aided by the advent of

  18. Mathematics applied to the climate system: outstanding challenges and recent progress

    PubMed Central

    Williams, Paul D.; Cullen, Michael J. P.; Davey, Michael K.; Huthnance, John M.

    2013-01-01

    The societal need for reliable climate predictions and a proper assessment of their uncertainties is pressing. Uncertainties arise not only from initial conditions and forcing scenarios, but also from model formulation. Here, we identify and document three broad classes of problems, each representing what we regard to be an outstanding challenge in the area of mathematics applied to the climate system. First, there is the problem of the development and evaluation of simple physically based models of the global climate. Second, there is the problem of the development and evaluation of the components of complex models such as general circulation models. Third, there is the problem of the development and evaluation of appropriate statistical frameworks. We discuss these problems in turn, emphasizing the recent progress made by the papers presented in this Theme Issue. Many pressing challenges in climate science require closer collaboration between climate scientists, mathematicians and statisticians. We hope the papers contained in this Theme Issue will act as inspiration for such collaborations and for setting future research directions. PMID:23588054

  19. Interactions between learning and evolution: the outstanding strategy generated by the Baldwin effect.

    PubMed

    Suzuki, Reiji; Arita, Takaya

    2004-11-01

    The Baldwin effect is known as an possible interaction between learning and evolution, where individual lifetime learning can influence the course of evolution without using any Lamarckian mechanism. Our concern is to consider the Baldwin effect in dynamic environments, especially when there is no explicit optimal solution through generations and this solution depends only on interactions among agents. We adopted the iterated Prisoner's Dilemma as a dynamic environment, introduced phenotypic plasticity into its strategies, and conducted computational experiments, in which phenotypic plasticity is allowed to evolve. The Baldwin effect was observed in the experiments as follows: First, strategies with enough plasticity spread, which caused a shift from defect-oriented populations to cooperative populations. Second, these strategies were replaced by a strategy with a modest amount of plasticity generated by interactions between learning and evolution. By making three kinds of analysis, we have shown that this strategy provides outstanding performance in comparison with other deterministic strategies. Further experiments towards open-ended evolution have also been conducted so as to generalize our results.

  20. Nonlinear generalization of Den Hartog's equal-peak method

    NASA Astrophysics Data System (ADS)

    Habib, G.; Detroux, T.; Viguié, R.; Kerschen, G.

    2015-02-01

    This study addresses the mitigation of a nonlinear resonance of a mechanical system. In view of the narrow bandwidth of the classical linear tuned vibration absorber, a nonlinear absorber, termed the nonlinear tuned vibration absorber (NLTVA), is introduced in this paper. An unconventional aspect of the NLTVA is that the mathematical form of its restoring force is tailored according to the nonlinear restoring force of the primary system. The NLTVA parameters are then determined using a nonlinear generalization of Den Hartog's equal-peak method. The mitigation of the resonant vibrations of a Duffing oscillator is considered to illustrate the proposed developments.

  1. Fault diagnosis for a class of nonlinear systems via ESO.

    PubMed

    Yan, Bingyong; Tian, Zuohua; Shi, Songjiao; Weng, Zhengxin

    2008-10-01

    In this paper, a novel fault detection and identification (FDI) scheme for a class of nonlinear systems is presented. First of all, an augment system is constructed by making the unknown system faults as an extended system state. Then based on the ESO theory, a novel fault diagnosis filter is constructed to diagnose the nonlinear system faults. An extension to a class of nonlinear uncertain systems is then made. An outstanding feature of this scheme is that it can simultaneously detect and identify the shape and magnitude of the system faults in real time without training the network compared with the neural network-based FDI schemes. Finally, simulation examples are given to illustrate the feasibility and effectiveness of the proposed approach.

  2. Whispering gallery resonator from lithium tetraborate for nonlinear optics

    NASA Astrophysics Data System (ADS)

    Fürst, Josef Urban; Buse, Karsten; Breunig, Ingo; Becker, Petra; Liebertz, Josef; Bohaty, Ladislav

    2015-02-01

    For second-order nonlinear-optical processes in the ultraviolet, appropriate materials with a sufficiently large band-gap typically exhibit smaller nonlinear coefficients than materials with comparably smaller band-gap. Whispering gallery resonators, with their outstanding quality factors, provide field enhancement and can compensate for these small coefficients. We report on the successful fabrication of a whispering gallery resonator made of lithium tetraborate, a suitable material for ultraviolet applications with a small nonlinear coefficient of d31 = 0:073 pm/V. Quality factors of the order of 108 are observed from the ultraviolet to the near-infrared spectrum. The inferred absorption coefficients of lithium tetraborate are below 0.2 m-1 in the visible and near-infrared. Continuous-wave second harmonic generation from 490 nm light to 245 nm is observed with conversion efficiencies up to 2.2 %.

  3. Every Other Day. Keynote Address.

    ERIC Educational Resources Information Center

    Tiller, Tom

    Schools need to be reoriented and restructured so that what is taught and learned, and the way in which it is taught and learned, are better integrated with young people's real-world experiences. Many indicators suggest that the meaningful aspects of school have been lost in the encounter with modern times. The title of this address--"Every…

  4. Agenda to address climate change

    SciTech Connect

    1998-10-01

    This document looks at addressing climate change in the 21st century. Topics covered are: Responding to climate change; exploring new avenues in energy efficiency; energy efficiency and alternative energy; residential sector; commercial sector; industrial sector; transportation sector; communities; renewable energy; understanding forests to mitigate and adapt to climate change; the Forest Carbon budget; mitigation and adaptation.

  5. Addressing Phonological Questions with Ultrasound

    ERIC Educational Resources Information Center

    Davidson, Lisa

    2005-01-01

    Ultrasound can be used to address unresolved questions in phonological theory. To date, some studies have shown that results from ultrasound imaging can shed light on how differences in phonological elements are implemented. Phenomena that have been investigated include transitional schwa, vowel coalescence, and transparent vowels. A study of…

  6. Keynote Address: Rev. Mark Massa

    ERIC Educational Resources Information Center

    Massa, Mark S.

    2011-01-01

    Rev. Mark S. Massa, S.J., is the dean and professor of Church history at the School of Theology and Ministry at Boston College. He was invited to give a keynote to begin the third Catholic Higher Education Collaborative Conference (CHEC), cosponsored by Boston College and Fordham University. Fr. Massa's address posed critical questions about…

  7. State of the Lab Address

    ScienceCinema

    King, Alex

    2016-07-12

    In his third-annual State of the Lab address, Ames Laboratory Director Alex King called the past year one of "quiet but strong progress" and called for Ames Laboratory to continue to build on its strengths while responding to changing expectations for energy research.

  8. Research strategies for addressing uncertainties

    USGS Publications Warehouse

    Busch, David E.; Brekke, Levi D.; Averyt, Kristen; Jardine, Angela; Welling, Leigh; Garfin, Gregg; Jardine, Angela; Merideth, Robert; Black, Mary; LeRoy, Sarah

    2013-01-01

    Research Strategies for Addressing Uncertainties builds on descriptions of research needs presented elsewhere in the book; describes current research efforts and the challenges and opportunities to reduce the uncertainties of climate change; explores ways to improve the understanding of changes in climate and hydrology; and emphasizes the use of research to inform decision making.

  9. 43 CFR 3195.35 - What happens if I have an outstanding obligation to purchase refined helium under a Helium...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... obligation to purchase refined helium under a Helium Distribution Contract? 3195.35 Section 3195.35 Public... OF THE INTERIOR MINERALS MANAGEMENT (3000) HELIUM CONTRACTS Federal Helium Supplier Requirements § 3195.35 What happens if I have an outstanding obligation to purchase refined helium under a...

  10. 43 CFR 3195.35 - What happens if I have an outstanding obligation to purchase refined helium under a Helium...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... obligation to purchase refined helium under a Helium Distribution Contract? 3195.35 Section 3195.35 Public... OF THE INTERIOR MINERALS MANAGEMENT (3000) HELIUM CONTRACTS Federal Helium Supplier Requirements § 3195.35 What happens if I have an outstanding obligation to purchase refined helium under a...

  11. 43 CFR 3195.35 - What happens if I have an outstanding obligation to purchase refined helium under a Helium...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... obligation to purchase refined helium under a Helium Distribution Contract? 3195.35 Section 3195.35 Public... OF THE INTERIOR MINERALS MANAGEMENT (3000) HELIUM CONTRACTS Federal Helium Supplier Requirements § 3195.35 What happens if I have an outstanding obligation to purchase refined helium under a...

  12. Unconscious and Unnoticed Professional Practice within an Outstanding School for Children and Young People with Complex Learning Difficulties and Disabilities

    ERIC Educational Resources Information Center

    Crombie, Richard; Sullivan, Lesley; Walker, Kate; Warnock, Rebecca

    2014-01-01

    This article describes a three-year project undertaken at Pear Tree School for children and young people with severe and multiple and profound learning difficulties. Lesley Sullivan, the school's head teacher, believed that much of the value within the work of this outstanding school went unidentified by existing approaches to planning, monitoring…

  13. Here's Your Syllabus, See You Next Week: A Review of the First Day Practices of Outstanding Professors

    ERIC Educational Resources Information Center

    Iannarelli, Barbara A.; Bardsley, Mary Ellen; Foote, Chandra J.

    2010-01-01

    Faculty teaching courses at the higher education level employ a wide variety of strategies on the first day of class. Little research has been conducted on the efficacy of these practices. This study examines the first-day practices of instructors of higher education classes who have been recognized as outstanding practitioners by their respective…

  14. 43 CFR 3195.35 - What happens if I have an outstanding obligation to purchase refined helium under a Helium...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... obligation to purchase refined helium under a Helium Distribution Contract? 3195.35 Section 3195.35 Public... OF THE INTERIOR MINERALS MANAGEMENT (3000) HELIUM CONTRACTS Federal Helium Supplier Requirements § 3195.35 What happens if I have an outstanding obligation to purchase refined helium under a...

  15. Blue Ribbon Schools: Outstanding Practices in Geography Education, 1989-90 and History Education, 1990-92.

    ERIC Educational Resources Information Center

    Office of Educational Research and Improvement (ED), Washington, DC. Programs for the Improvement of Practice.

    This document is a report on 16 schools selected as Blue Ribbon Schools for their outstanding programs in geography or history. The report is divided into four parts. The first part discusses the curricular frameworks and guidelines for elementary and secondary schools in geography education. Areas discussed include: (1) current achievement and…

  16. 41 CFR 301-71.304 - Are we responsible for ensuring the collection of outstanding travel advances?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ensuring the collection of outstanding travel advances? 301-71.304 Section 301-71.304 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES AGENCY RESPONSIBILITIES 71-AGENCY TRAVEL ACCOUNTABILITY REQUIREMENTS Accounting for Travel Advances § 301-71.304 Are...

  17. Filtering by nonlinear systems.

    PubMed

    Campos Cantón, E; González Salas, J S; Urías, J

    2008-12-01

    Synchronization of nonlinear systems forced by external signals is formalized as the response of a nonlinear filter. Sufficient conditions for a nonlinear system to behave as a filter are given. Some examples of generalized chaos synchronization are shown to actually be special cases of nonlinear filtering.

  18. What makes astronomical heritage valuable? Identifying potential Outstanding Universal Value in cultural properties relating to astronomy

    NASA Astrophysics Data System (ADS)

    Cotte, Michel

    2015-08-01

    The communication will present the today situation of astronomical and archaeo-astronomical heritage related to the World Heritage Convention along the past years till today. Some parallel events and works promoted strongly as the IAU - UNESCO initiative for the “year of astronomy” (2009). It was followed by a joint program by IAU and ICOMOS who is an official advisory body assessing the World Heritage Committee for the evaluation of nomination dossiers. Result of that works is an important publication by around 40 authors coming from 20 different countries all around the World: Heritage Sites of Astronomy and Archaeoastronomy in context of the UNESCO World Heritage Convention (2010-2011). A second volume is under preparation (2015). It was also accompanied by some initiatives like “Windows to the Universe” organisation and parallel constitution of local “Starlight Reserves”. Some regional meetings studying specific facets or regional heritage in the field giving significant knowledge progresses also accompanied global trend for astronomical heritage.WH assessment is defined by a relatively strict format and methodology. Key word is “demonstration of an Outstanding Universal Value” to justify the WH Listing by the Committee. Communication first examines requirements and evaluation practices about of the OUV demonstration for a given place in context of astronomical or archaeo-astronomical heritage. That means examination of the tangible attributes, inventory of the property in terms of unmoveable and moveable components and inventory of intangible issues related to the history (history of the place in context of the history of astronomy and cultural history). That is also related to apply to the site concept of integrity and authenticity level of the place and comparison with other similar places (WH site already listed, national WH Tentative List, other similar places in the region).Second issue of the communication is to give a glimpse on the

  19. Gold deposits in metamorphic belts: Overview of current understanding, outstanding problems, future research, and exploration significance

    USGS Publications Warehouse

    Groves, D.I.; Goldfarb, R.J.; Robert, F.; Hart, C.J.R.

    2003-01-01

    Metamorphic belts are complex regions where accretion or collision has added to, or thickened, continental crust. Gold-rich deposits can be formed at all stages of orogen evolution, so that evolving metamorphic belts contain diverse gold deposit types that may be juxtaposed or overprint each other. This partly explains the high level of controversy on the origin of some deposit types, particularly those formed or overprinted/remobilized during the major compressional orogeny that shaped the final geometry of the hosting metamorphic belts. These include gold-dominated orogenic and intrusion-related deposits, but also particularly controversial gold deposits with atypical metal associations. There are a number of outstanding problems for all types of gold deposits in metamorphc belts. These include the following: (1) definitive classifications, (2) unequivocal recognition of fluid and metal sources, (3) understanding of fluid migration and focusing at all scales, (4) resolution of the precise role of granitoid magmatism, (5) precise gold-depositional mechanisms, particularly those producing high gold grades, and (6) understanding of the release of CO2-rich fluids from subducting slabs and subcreted oceanic crust and granitoid magmas at different crustal levels. Research needs to be better coordinated and more integrated, such that detailed fluid-inclusion, trace-element, and isotopic studies of both gold deposits and potential source rocks, using cutting-edge technology, are embedded in a firm geological framework at terrane to deposit scales. Ultimately, four-dimensional models need to be developed, involving high-quality, three-dimensional geological data combined with integrated chemical and fluid-flow modeling, to understand the total history of the hydrothermal systems involved. Such research, particularly that which can predict superior targets visible in data sets available to exploration companies before discovery, has obvious spin-offs for global- to deposit

  20. Chirped nonlinear resonance dynamics in phase space

    NASA Astrophysics Data System (ADS)

    Friedland, Lazar; Armon, Tsafrir

    2016-10-01

    Passage through and capture into resonance in systems with slowly varying parameters is one of the outstanding problems of nonlinear dynamics. Examples include resonant capture in planetary dynamics , resonant excitation of nonlinear waves, adiabatic resonant transitions in atomic and molecular systems and more. In the most common setting the problem involves a nonlinear oscillator driven by an oscillating perturbation with a slowly varying frequency, which passes through the resonance with the unperturbed oscillator. The process of resonant capture in this case involves crossing of separatrix and, therefore, the adiabatic theorem cannot be used in studying this problem no matter how slow is the variation of the driving frequency. It will be shown that if instead of analyzing complicated single orbit dynamics in passage through resonance, one considers the evolution of a distribution of initial conditions in phase space, simple adiabaticity and phase space incompressibility arguments yield a solution to the resonant capture probability problem. The approach will be illustrated in the case of a beam of charged particles driven by a chirped frequency wave passing through the Cherenkov resonance with the velocity distribution of the particles. Supported by Israel Science Foundation Grant 30/14.

  1. Atomic clusters with addressable complexity

    NASA Astrophysics Data System (ADS)

    Wales, David J.

    2017-02-01

    A general formulation for constructing addressable atomic clusters is introduced, based on one or more reference structures. By modifying the well depths in a given interatomic potential in favour of nearest-neighbour interactions that are defined in the reference(s), the potential energy landscape can be biased to make a particular permutational isomer the global minimum. The magnitude of the bias changes the resulting potential energy landscape systematically, providing a framework to produce clusters that should self-organise efficiently into the target structure. These features are illustrated for small systems, where all the relevant local minima and transition states can be identified, and for the low-energy regions of the landscape for larger clusters. For a 55-particle cluster, it is possible to design a target structure from a transition state of the original potential and to retain this structure in a doubly addressable landscape. Disconnectivity graphs based on local minima that have no direct connections to a lower minimum provide a helpful way to visualise the larger databases. These minima correspond to the termini of monotonic sequences, which always proceed downhill in terms of potential energy, and we identify them as a class of biminimum. Multiple copies of the target cluster are treated by adding a repulsive term between particles with the same address to maintain distinguishable targets upon aggregation. By tuning the magnitude of this term, it is possible to create assemblies of the target cluster corresponding to a variety of structures, including rings and chains.

  2. EDITORIAL: Announcing the 2006 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Fujii, Kenichi; Regtien, Paul

    2007-07-01

    Since 1991, Measurement Science and Technology has awarded a Best Paper prize. The Editorial Board of this journal believes that such a prize is an opportunity to thank authors for submitting their work, and serves as an integral part of the on-going quality review of the journal. The current breadth of topical areas that are covered by MST has made it advisable to expand the recognition of excellent publications. Hence, since 2005 the Editorial Board have presented 'Outstanding Paper Awards' in four subject categories: Fluid Mechanics; Measurement Science; Precision Measurements; and Sensors and Sensing Systems. 2006 Award Winners—Fluid Mechanics The article 'Molecular tagging velocimetry and thermometry and its application to the wake of a heated circular cylinder' by Hui Hu and Manoochehr Koochesfahani, published in volume 17, issue 6, pp 1269-1281, was selected by the cognizant Editorial Board Members as the Outstanding Paper in Fluid Mechanics for 2006. This consensus selection was accompanied by the collective judgment that a number of other very strong contributions were published in 2006. These other papers have been added to the 2006 Highlights in the electronic version of the journal. The paper by Hu and Koochesfahani is recognized for its contribution to the use of molecular tagging techniques in the service of velocity and temperature measurements. The paper clearly articulates the prior state-of-the-art in this area and it communicates the required equipment and procedures to utilize this experimental tool. The capabilities of their technique are made apparent by the simultaneous (u,v,T) observations in the wake of a circular cylinder. The normalized heat flux vectors, (\\overline{u_j'T'})/U\\Delta T, demonstrate one of the beneficial results of obtaining a whole-field view of the velocity and temperature distributions. The authors also have carefully noted the intrinsic limitations of their technique. 2006 Award Winners—Measurement Science The

  3. Nonvolatile Memory Based on Nonlinear Magnetoelectric Effects

    NASA Astrophysics Data System (ADS)

    Shen, Jianxin; Cong, Junzhuang; Chai, Yisheng; Shang, Dashan; Shen, Shipeng; Zhai, Kun; Tian, Ying; Sun, Young

    2016-08-01

    The magnetoelectric effects in multiferroics have a great potential in creating next-generation memory devices. We use an alternative concept of nonvolatile memory based, on a type of nonlinear magnetoelectric effects showing a butterfly-shaped hysteresis loop. The principle is to utilize the states of the magnetoelectric coefficient, instead of magnetization, electric polarization, or resistance, to store binary information. Our experiments in a device made of the PMN-PT/Terfenol-D multiferroic heterostructure clearly demonstrate that the sign of the magnetoelectric coefficient can be repeatedly switched between positive and negative by applying electric fields, confirming the feasibility of this principle. This kind of nonvolatile memory has outstanding practical virtues such as simple structure, easy operation in writing and reading, low power, fast speed, and diverse materials available.

  4. Chaotic Dynamics and Application of LCR Oscillators Sharing Common Nonlinearity

    NASA Astrophysics Data System (ADS)

    Jeevarekha, A.; Paul Asir, M.; Philominathan, P.

    2016-06-01

    This paper addresses the problem of sharing common nonlinearity among nonautonomous and autonomous oscillators. By choosing a suitable common nonlinear element with the driving point characteristics capable of bringing out chaotic motion in a combined system, we obtain identical chaotic states. The dynamics of the coupled system is explored through numerical and experimental studies. Employing the concept of common nonlinearity, a simple chaotic communication system is modeled and its performance is verified through Multisim simulation.

  5. Applications of nonlinear system identification to structural health monitoring.

    SciTech Connect

    Farrar, C. R.; Sohn, H.; Robertson, A. N.

    2004-01-01

    The process of implementing a damage detection strategy for aerospace, civil and mechanical engineering infrastructure is referred to as structural health monitoring (SHM). In many cases damage causes a structure that initially behaves in a predominantly linear manner to exhibit nonlinear response when subject to its operating environment. The formation of cracks that subsequently open and close under operating loads is an example of such damage. The damage detection process can be significantly enhanced if one takes advantage of these nonlinear effects when extracting damage-sensitive features from measured data. This paper will provide an overview of nonlinear system identification techniques that are used for the feature extraction process. Specifically, three general approaches that apply nonlinear system identification techniques to the damage detection process are discussed. The first two approaches attempt to quantify the deviation of the system from its initial linear characteristics that is a direct result of damage. The third approach is to extract features from the data that are directly related to the specific nonlinearity associated with the damaged condition. To conclude this discussion, a summary of outstanding issues associated with the application of nonlinear system identification techniques to the SHM problem is presented.

  6. Identifying and Addressing Vaccine Hesitancy

    PubMed Central

    Kestenbaum, Lori A.; Feemster, Kristen A.

    2015-01-01

    In the 20th century, the introduction of multiple vaccines significantly reduced childhood morbidity, mortality, and disease outbreaks. Despite, and perhaps because of, their public health impact, an increasing number of parents and patients are choosing to delay or refuse vaccines. These individuals are described as vaccine hesitant. This phenomenon has developed due to the confluence of multiple social, cultural, political and personal factors. As immunization programs continue to expand, understanding and addressing vaccine hesitancy will be crucial to their successful implementation. This review explores the history of vaccine hesitancy, its causes, and suggested approaches for reducing hesitancy and strengthening vaccine acceptance. PMID:25875982

  7. Identifying and addressing vaccine hesitancy.

    PubMed

    Kestenbaum, Lori A; Feemster, Kristen A

    2015-04-01

    In the 20th century, the introduction of multiple vaccines significantly reduced childhood morbidity, mortality, and disease outbreaks. Despite, and perhaps because of, their public health impact, an increasing number of parents and patients are choosing to delay or refuse vaccines. These individuals are described as "vaccine hesitant." This phenomenon has developed due to the confluence of multiple social, cultural, political, and personal factors. As immunization programs continue to expand, understanding and addressing vaccine hesitancy will be crucial to their successful implementation. This review explores the history of vaccine hesitancy, its causes, and suggested approaches for reducing hesitancy and strengthening vaccine acceptance.

  8. Nanoscale content-addressable memory

    NASA Technical Reports Server (NTRS)

    Davis, Bryan (Inventor); Principe, Jose C. (Inventor); Fortes, Jose (Inventor)

    2009-01-01

    A combined content addressable memory device and memory interface is provided. The combined device and interface includes one or more one molecular wire crossbar memories having spaced-apart key nanowires, spaced-apart value nanowires adjacent to the key nanowires, and configurable switches between the key nanowires and the value nanowires. The combination further includes a key microwire-nanowire grid (key MNG) electrically connected to the spaced-apart key nanowires, and a value microwire-nanowire grid (value MNG) electrically connected to the spaced-apart value nanowires. A key or value MNGs selects multiple nanowires for a given key or value.

  9. Addressing inequities in healthy eating.

    PubMed

    Friel, Sharon; Hattersley, Libby; Ford, Laura; O'Rourke, Kerryn

    2015-09-01

    What, when, where and how much people eat is influenced by a complex mix of factors at societal, community and individual levels. These influences operate both directly through the food system and indirectly through political, economic, social and cultural pathways that cause social stratification and influence the quality of conditions in which people live their lives. These factors are the social determinants of inequities in healthy eating. This paper provides an overview of the current evidence base for addressing these determinants and for the promotion of equity in healthy eating.

  10. Addressing the workforce pipeline challenge

    SciTech Connect

    Leonard Bond; Kevin Kostelnik; Richard Holman

    2006-11-01

    A secure and affordable energy supply is essential for achieving U.S. national security, in continuing U.S. prosperity and in laying the foundations to enable future economic growth. To meet this goal the next generation energy workforce in the U.S., in particular those needed to support instrumentation, controls and advanced operations and maintenance, is a critical element. The workforce is aging and a new workforce pipeline, to support both current generation and new build has yet to be established. The paper reviews the challenges and some actions being taken to address this need.

  11. What makes astronomical heritage valuable? Identifying potential Outstanding Universal Value in cultural properties relating to astronomy

    NASA Astrophysics Data System (ADS)

    Cotte, Michel

    2016-10-01

    This communication presents the situation regarding astronomical and archaeoastronomical heritage related to the World Heritage Convention through recent years up until today. Some parallel events and works were promoted strongly within the IAU-UNESCO Initiative during the International Year of Astronomy (2009). This was followed by a joint program by the IAU and ICOMOS-an official advisory body assisting the World Heritage Committee in the evaluation of nomination dossiers. The result of that work is an important publication by around 40 authors from 20 different countries all around the world: Heritage Sites of Astronomy and Archaeoastronomy in the Context of the UNESCO World Heritage Convention (Ruggles & Cotte 2010). A second volume is under preparation (2015). It was also accompanied by some initiatives such as the ``Windows to the Universe" organisation and the parallel constitution of local ``Starlight Reserves''. Some regional meetings studying specific facets or regional heritage in the field giving significant knowledge progresses also accompanied the global trend for astronomical heritage. WH assessment is defined by a relatively strict format and methodology. A key phrase is ``demonstration of Outstanding Universal Value'' to justify the WH Listing by the Committee. This communication first examines the requirements and evaluation practices about of demonstrating OUV for a given place in the context of astronomical or archaeoastronomical heritage. That means the examination of the tangible attributes, an inventory of the property in terms of immoveable and moveable components and an inventory of intangible issues related to the history (history of the place in the context of the history of astronomy and cultural history). This is also related to the application to the site of the concept of integrity and authenticity, as regards the place itself and in comparison with other similar places (WH sites already listed, sites on national WH Tentative Lists

  12. Outstanding imprints of c. 200 million year old earthquakes in seafloor sediments

    NASA Astrophysics Data System (ADS)

    Homberg, Catherine; Schnyder, Johann; Borderie, Sandra; Raine, Rob

    2015-04-01

    - Early Jurassic. Based on this outstanding example, we proposed a sequential model for the deformation and disturbance of the seafloor subsurface sediments triggered by an earthquake. The sequence of deformation includes brittle failure, fluidization of the failed unit, plastic deformation, and sediment flow at designated places (e.g. close to the fault tips). We also discuss the roles of contrasting stiffness, shear strength, and thickness of the units on the sediment destabilization of freshly deposited sediments that are characterized by a prominent mechanical layering.

  13. Assessing the outstanding 2003 fire events in Portugal with a Regional Climate Model

    NASA Astrophysics Data System (ADS)

    Trigo, Ricardo; Jerez, Sonia; Camara, Carlos; Montávez, Juan Pedro

    2013-04-01

    The heatwave that struck western Iberia in the early days of August 2003 was characterized by record high values of both maximum (47.3°C) and minimum (30.6°c) temperatures in Portugal, associated with extremely low humidity levels and relatively intense wind speed (Trigo et al., 2006). These conditions triggered the most devastating sequence of large fires ever registered in Portugal. The estimated total burnt area was about 450.000 ha, including 280.000 ha of forest (Pereira et al., 2011). The outstanding total burnt area value corresponds to roughly 5% of the Portuguese territory, and represents approximately twice the previous maximum observed in 1998 (~220.000 ha), and about four times the long-term average observed between 1980 and 2004. Here we characterise this unusual episode using meteorological fields obtained from both observations and a regional climate model. In this work we use the longest (49-years) high-resolution regional climate simulation available driven by reanalysis data spanning from 1959 to 2007 and covering the entire Iberian Peninsula. This long run was obtained using the MM5 model with a spatial resolution of 10 km. Using this high spatial and temporal resolution we have computed the Canadian Fire Weather Index (FWI) System to produce hourly values of fire risk. The FWI System consists of six components that account for the effects of fuel moisture and wind on fire behaviour (van Wagner, 1987). We show the temporal evolution of high resolution patterns for several fire related variables during the most important days for triggering new fires (the first week of August 2003). Besides the absolute value of Tmax, Tmin, wind (speed and direction), relative humidity and FWI we also evaluate the corresponding anomalies of these fields, obtained after removing the long-term smoothed daily climatology. Pereira M.G., Malamude B.D., Trigo R.M., Alves P.I. (2011) "The History and Characteristics of the 1980-2005 Portuguese Rural Fire Database

  14. 41 CFR 301-52.14 - What must I do with any travel advance outstanding at the time I submit my travel claim?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... travel advance outstanding at the time I submit my travel claim? 301-52.14 Section 301-52.14 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES... § 301-52.14 What must I do with any travel advance outstanding at the time I submit my travel claim?...

  15. 41 CFR 301-52.14 - What must I do with any travel advance outstanding at the time I submit my travel claim?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... travel advance outstanding at the time I submit my travel claim? 301-52.14 Section 301-52.14 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES... § 301-52.14 What must I do with any travel advance outstanding at the time I submit my travel claim?...

  16. 41 CFR 301-52.14 - What must I do with any travel advance outstanding at the time I submit my travel claim?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... travel advance outstanding at the time I submit my travel claim? 301-52.14 Section 301-52.14 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES... § 301-52.14 What must I do with any travel advance outstanding at the time I submit my travel claim?...

  17. 41 CFR 301-52.14 - What must I do with any travel advance outstanding at the time I submit my travel claim?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... travel advance outstanding at the time I submit my travel claim? 301-52.14 Section 301-52.14 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES... § 301-52.14 What must I do with any travel advance outstanding at the time I submit my travel claim?...

  18. 41 CFR 301-52.14 - What must I do with any travel advance outstanding at the time I submit my travel claim?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... travel advance outstanding at the time I submit my travel claim? 301-52.14 Section 301-52.14 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES... § 301-52.14 What must I do with any travel advance outstanding at the time I submit my travel claim?...

  19. PREDICTION OF NONLINEAR SPATIAL FUNCTIONALS. (R827257)

    EPA Science Inventory

    Spatial statistical methodology can be useful in the arena of environmental regulation. Some regulatory questions may be addressed by predicting linear functionals of the underlying signal, but other questions may require the prediction of nonlinear functionals of the signal. ...

  20. Electromagnetic nonlinear gyrokinetics with polarization drift

    SciTech Connect

    Duthoit, F.-X.; Hahm, T. S.; Wang, Lu

    2014-08-15

    A set of new nonlinear electromagnetic gyrokinetic Vlasov equation with polarization drift and gyrokinetic Maxwell equations is systematically derived by using the Lie-transform perturbation method in toroidal geometry. For the first time, we recover the drift-kinetic expression for parallel acceleration [R. M. Kulsrud, in Basic Plasma Physics, edited by A. A. Galeev and R. N. Sudan (North-Holland, Amsterdam, 1983)] from the nonlinear gyrokinetic equations, thereby bridging a gap between the two formulations. This formalism should be useful in addressing nonlinear ion Compton scattering of intermediate-mode-number toroidal Alfvén eigenmodes for which the polarization current nonlinearity [T. S. Hahm and L. Chen, Phys. Rev. Lett. 74, 266 (1995)] and the usual finite Larmor radius effects should compete.

  1. Electromagnetic nonlinear gyrokinetics with polarization drift

    NASA Astrophysics Data System (ADS)

    Duthoit, F.-X.; Hahm, T. S.; Wang, Lu

    2014-08-01

    A set of new nonlinear electromagnetic gyrokinetic Vlasov equation with polarization drift and gyrokinetic Maxwell equations is systematically derived by using the Lie-transform perturbation method in toroidal geometry. For the first time, we recover the drift-kinetic expression for parallel acceleration [R. M. Kulsrud, in Basic Plasma Physics, edited by A. A. Galeev and R. N. Sudan (North-Holland, Amsterdam, 1983)] from the nonlinear gyrokinetic equations, thereby bridging a gap between the two formulations. This formalism should be useful in addressing nonlinear ion Compton scattering of intermediate-mode-number toroidal Alfvén eigenmodes for which the polarization current nonlinearity [T. S. Hahm and L. Chen, Phys. Rev. Lett. 74, 266 (1995)] and the usual finite Larmor radius effects should compete.

  2. Low-cost capacitor voltage inverter for outstanding performance in piezoelectric energy harvesting.

    PubMed

    Lallart, Mickaël; Garbuio, Lauric; Richard, Claude; Guyomar, Daniel

    2010-01-01

    The purpose of this paper is to propose a new scheme for piezoelectric energy harvesting optimization. The proposed enhancement relies on a new topology for inverting the voltage across a single capacitor with reduced losses. The increase of the inversion quality allows a much more effective energy harvesting process using the so-called synchronized switch harvesting on inductor (SSHI) nonlinear technique. It is shown that the proposed architecture, based on a 2-step inversion, increases the harvested power by a theoretical factor up to square root of 2 (i.e., 40% gain) compared with classical SSHI, allowing an increase of the harvested power by a factor greater than 1000% compared with the standard energy harvesting technique for realistic values of inversion components. The proposed circuit, using only 4 digital switches and an intermediate capacitor, is also ultra-low power, because the inversion circuit does not require any external energy and the command signals are very simple.

  3. Response theory for non-equilibrium systems: theory and applications (Outstanding Young Scientist Lecture)

    NASA Astrophysics Data System (ADS)

    Lucarini, Valerio

    2010-05-01

    We consider the general response theory recently proposed by Ruelle for describing the impact of small perturbations to the non-equilibrium steady states resulting from Axiom A dynamical systems. We show that the causality of the response functions entails the possibility of writing a set of Kramers-Kronig (K-K) relations for the corresponding susceptibilities at all orders of nonlinearity, and specific results are provided for the case of arbitrary order harmonic response. These results shed light on the very general impact of considering the principle of causality for testing self-consistency: the described dispersion relations constitute unavoidable benchmarks that any experimental and model generated dataset must obey. These results, taking into account the chaotic hypothesis by Gallavotti and Cohen, might be relevant in several fields, including climate research. In particular, whereas the fluctuation-dissipation theorem does not work for non-equilibrium systems, because of the non-equivalence between internal and external fluctuations, K-K relations might be robust tools for the definition of a self-consistent theory of climate change. Along these lines, we present here the first evidence of the validity of these integral relations for the linear and the second harmonic response for the perturbed Lorenz 63 system, by showing that numerical simulations agree up to high degree of accuracy with the theoretical predictions. The numerical results confirm the conceptual validity of the nonlinear response theory, suggest that the theory can be extended for more general non equilibrium steady state systems, and shed new light on the applicability of very general tools, based only upon the principle of causality, for diagnosing the behavior of perturbed chaotic systems and reconstructing their output signals.

  4. Nonlinear Hysteretic Torsional Waves

    NASA Astrophysics Data System (ADS)

    Cabaret, J.; Béquin, P.; Theocharis, G.; Andreev, V.; Gusev, V. E.; Tournat, V.

    2015-07-01

    We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found to be nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other types of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short-term memory, as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control devices such as strong amplitude-dependent filters.

  5. Nonlinear Hysteretic Torsional Waves.

    PubMed

    Cabaret, J; Béquin, P; Theocharis, G; Andreev, V; Gusev, V E; Tournat, V

    2015-07-31

    We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found to be nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other types of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short-term memory, as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control devices such as strong amplitude-dependent filters.

  6. The oceanographic and climatic evolution of the Paleogene Southern Ocean (Arne Richter Award for Outstanding Young Scientists Lecture)

    NASA Astrophysics Data System (ADS)

    Bijl, Peter; Houben, Alexander J. P.

    2014-05-01

    buildup of continental ice on Antarctica, sea-ice may have first developed along the margin of East Antarctica Margin, but this conclusion lacks support from field evidence. Other numerical models predict that hysteresis effects within the ice sheet render a continental-size Antarctic ice sheet rather insensitive to warming. In contrast, deep-water benthic foraminiferal oxygen isotope records across the Oligocene suggest dramatic waxing and waning of Antarctic ice sheets. In summary, the complex interaction of climate forcings and responses following the opening and subsequent deepening of the Southern Ocean gateways, as well as the precise relationship between Southern Ocean oceanographic change, sea ice formation and continental ice dynamics are as yet poorly understood. In my presentation, I will provide an overview of our recent palynological and organic geochemical studies on Eocene sediments from the Southern Ocean that addresses some of these uncertainties. The presented studies were only possible through access to ocean sediments collected and curated by the several scientific ocean drilling programs (DSDP, ODP, IODP). IODP Expedition 318 drilled the Antarctic Margin in 2010, and recovered sediments from both pre-glacial and early glacial phases of Antarctic climate evolution. Using these drill cores together with sediments retrieved during previous expeditions we can now evaluate the robustness of the results of numerical models with field data. Strata sampled at IODP Site U1356 represent a thick and relatively complete (albeit compromised by core gaps) Eocene- Oligocene succession that is chronostratigraphically well-calibrated in the context of of nannoplankton- dinoflagellate cyst (dinocyst) and paleomagnetism. Notably, this record yields diverse dinocysts assemblages and organic molecular biomarkers, which we can use to investigate changes in surface-water paleoenvironmental changes through the Eocene and Oligocene to provide answers to these outstanding

  7. 3D Interconnected and Multiwalled Carbon@MoS2 @Carbon Hollow Nanocables as Outstanding Anodes for Na-Ion Batteries.

    PubMed

    Wang, Yan; Qu, Qunting; Li, Guangchao; Gao, Tian; Qian, Feng; Shao, Jie; Liu, Weijie; Shi, Qiang; Zheng, Honghe

    2016-11-01

    Currently, the specific capacity and cycling performance of various MoS2 /carbon-based anode materials for Na-ion storage are far from satisfactory due to the insufficient structural stability of the electrode, incomplete protection of MoS2 by carbon, difficult access of electrolyte to the electrode interior, as well as inactivity of the adopted carbon matrix. To address these issues, this work presents the rational design and synthesis of 3D interconnected and hollow nanocables composed of multiwalled carbon@MoS2 @carbon. In this architecture, (i) the 3D nanoweb-like structure brings about excellent mechanical property of the electrode, (ii) the ultrathin MoS2 nanosheets are sandwiched between and doubly protected by two layers of porous carbon, (iii) the hollow structure of the primary nanofibers facilitates the access of electrolyte to the electrode interior, (iv) the porous and nitrogen-doping properties of the two carbon materials lead to synergistic Na-storage of carbon and MoS2 . As a result, this hybrid material as the anode material of Na-ion battery exhibits fast charge-transfer reaction, high utilization efficiency, and ultrastability. Outstanding reversible capacity (1045 mAh g(-1) ), excellent rate behavior (817 mAh g(-1) at 7000 mA g(-1) ), and good cycling performance (747 mAh g(-1) after 200 cycles at 700 mA g(-1) ) are obtained.

  8. Prediction of nonlinear jet noise propagation

    NASA Astrophysics Data System (ADS)

    Gee, Kent L.

    The role of nonlinearity in the propagation of noise radiated from high-performance jet aircraft has not been a well-understood phenomenon in the past. To address the problem of finite-amplitude noise propagation, a hybrid time-frequency domain model has been developed to numerically solve the generalized Mendousse-Burgers equation, which is a parabolic model equation that includes effects of quadratic nonlinearity, atmospheric absorption and dispersion, and geometrical spreading. The algorithm has been compared against analytical theory and numerical issues have been discussed. Three sets of experimental data have been used to evaluate the model: model-scale laboratory jet data, field data using a large loudspeaker, and static engine run-up measurements of the F/A-22 Raptor. Comparison of linearly- and nonlinearly-predicted spectra demonstrates that nonlinearity does, in fact, impact the noise propagation in all three sets of data. Additionally, the extensive comparison with the Raptor data shows that the model is successful in predicting the measured spectrum over multiple angles and engine conditions, demonstrating that the model captures much of the physics of the propagation, despite its current neglect of multipath interference and atmospheric refraction and turbulence effects. Two additional studies have been carried out in order to address fundamental questions relevant to the nonlinear propagation of jet noise: ''What is the impact of nonlinearity on perceived levels?" and ''At what point does the propagation become linear?" An investigation of the perceived impact of nonlinearity shows that there are only minor differences between nonlinear and linear predictions in calculations of power-based, single-number metrics, such as A-weighted overall sound pressure level. On the other hand, the actual perceived differences between nonlinear and linear waveforms are substantially greater and consequently do not correlate well with calculated metrics. This

  9. Content-addressable holographic databases

    NASA Astrophysics Data System (ADS)

    Grawert, Felix; Kobras, Sebastian; Burr, Geoffrey W.; Coufal, Hans J.; Hanssen, Holger; Riedel, Marc; Jefferson, C. Michael; Jurich, Mark C.

    2000-11-01

    Holographic data storage allows the simultaneous search of an entire database by performing multiple optical correlations between stored data pages and a search argument. We have recently developed fuzzy encoding techniques for this fast parallel search and demonstrated a holographic data storage system that searches digital data records with high fidelity. This content-addressable retrieval is based on the ability to take the two-dimensional inner product between the search page and each stored data page. We show that this ability is lost when the correlator is defocussed to avoid material oversaturation, but can be regained by the combination of a random phase mask and beam confinement through total internal reflection. Finally, we propose an architecture in which spatially multiplexed holograms are distributed along the path of the search beam, allowing parallel search of large databases.

  10. Addressing viral resistance through vaccines

    PubMed Central

    Laughlin, Catherine; Schleif, Amanda; Heilman, Carole A

    2015-01-01

    Antimicrobial resistance is a serious healthcare concern affecting millions of people around the world. Antiviral resistance has been viewed as a lesser threat than antibiotic resistance, but it is important to consider approaches to address this growing issue. While vaccination is a logical strategy, and has been shown to be successful many times over, next generation viral vaccines with a specific goal of curbing antiviral resistance will need to clear several hurdles including vaccine design, evaluation and implementation. This article suggests that a new model of vaccination may need to be considered: rather than focusing on public health, this model would primarily target sectors of the population who are at high risk for complications from certain infections. PMID:26604979

  11. Addressing Failures in Exascale Computing

    SciTech Connect

    Snir, Marc; Wisniewski, Robert; Abraham, Jacob; Adve, Sarita; Bagchi, Saurabh; Balaji, Pavan; Belak, J.; Bose, Pradip; Cappello, Franck; Carlson, Bill; Chien, Andrew; Coteus, Paul; DeBardeleben, Nathan; Diniz, Pedro; Engelmann, Christian; Erez, Mattan; Fazzari, Saverio; Geist, Al; Gupta, Rinku; Johnson, Fred; Krishnamoorthy, Sriram; Leyffer, Sven; Liberty, Dean; Mitra, Subhasish; Munson, Todd; Schreiber, Rob; Stearley, Jon; Van Hensbergen, Eric

    2014-01-01

    We present here a report produced by a workshop on Addressing failures in exascale computing' held in Park City, Utah, 4-11 August 2012. The charter of this workshop was to establish a common taxonomy about resilience across all the levels in a computing system, discuss existing knowledge on resilience across the various hardware and software layers of an exascale system, and build on those results, examining potential solutions from both a hardware and software perspective and focusing on a combined approach. The workshop brought together participants with expertise in applications, system software, and hardware; they came from industry, government, and academia, and their interests ranged from theory to implementation. The combination allowed broad and comprehensive discussions and led to this document, which summarizes and builds on those discussions.

  12. Addressing failures in exascale computing

    SciTech Connect

    Snir, Marc; Wisniewski, Robert W.; Abraham, Jacob A.; Adve, Sarita; Bagchi, Saurabh; Balaji, Pavan; Belak, Jim; Bose, Pradip; Cappello, Franck; Carlson, William; Chien, Andrew A.; Coteus, Paul; Debardeleben, Nathan A.; Diniz, Pedro; Engelmann, Christian; Erez, Mattan; Saverio, Fazzari; Geist, Al; Gupta, Rinku; Johnson, Fred; Krishnamoorthy, Sriram; Leyffer, Sven; Liberty, Dean; Mitra, Subhasish; Munson, Todd; Schreiber, Robert; Stearly, Jon; Van Hensbergen, Eric

    2014-05-01

    We present here a report produced by a workshop on “Addressing Failures in Exascale Computing” held in Park City, Utah, August 4–11, 2012. The charter of this workshop was to establish a common taxonomy about resilience across all the levels in a computing system; discuss existing knowledge on resilience across the various hardware and software layers of an exascale system; and build on those results, examining potential solutions from both a hardware and software perspective and focusing on a combined approach. The workshop brought together participants with expertise in applications, system software, and hardware; they came from industry, government, and academia; and their interests ranged from theory to implementation. The combination allowed broad and comprehensive discussions and led to this document, which summarizes and builds on those discussions.

  13. Light addressable photoelectrochemical cyanide sensor

    SciTech Connect

    Licht, S.; Myung, N.; Sun, Y.

    1996-03-15

    A sensor is demonstrated that is capable of spatial discrimination of cyanide with use of only a single stationary sensing element. Different spatial regions of the sensing element are light activated to reveal the solution cyanide concentration only at the point of illumination. In this light addressable photoelectrochemical (LAP) sensor the sensing element consists of an n-CdSe electrode immersed in solution, with the open-circuit potential determined under illumination. In alkaline ferro-ferri-cyanide solution, the open-circuit photopotential is highly responsive to cyanide, with a linear response of (120 mV) log [KCN]. LAP detection with a spatial resolution of {+-}1 mm for cyanide detection is demonstrated. The response is almost linear for 0.001-0.100 m cyanide with a resolution of 5 mV. 38 refs., 7 figs., 1 tab.

  14. Nonlinear flight control design using backstepping methodology

    NASA Astrophysics Data System (ADS)

    Tran, Thanh Trung

    eliminating the pseudo control transformations. In the second part, the research focuses on nonlinear control design for flight dynamics of aircraft motion. Some assumptions on aerodynamics of the aircraft are addressed to transform full nonlinear flight dynamics into the canonical strict-feedback form. The assumptions are also analyzed, validated, and compared to show the advantages and disadvantages of the design models. With the achieved models, investigation focuses on formulating the backstepping control laws and provides an advanced control algorithm for nonlinear flight dynamics of the aircraft. Experimental and simulation studies are successfully implemented to validate the proposed control method. Advancement of nonlinear backstepping control theory and its application to nonlinear flight control are achieved in the dissertation research.

  15. EDITORIAL: Announcing the 2007 Measurement Science and Technology Outstanding Paper Awards

    NASA Astrophysics Data System (ADS)

    Foss, John; Dewhurst, Richard; Fujii, Kenichi; Regtien, Paul

    2008-05-01

    Since 1991, Measurement Science and Technology has awarded a Best Paper prize. The Editorial Board of this journal believes that such a prize is an opportunity to thank authors for submitting their work, and serves as an integral part of the on-going quality review of the journal. The current breadth of topical areas that are covered by MST has made it advisable to expand the recognition of excellent publications. Hence, since 2005 the Editorial Board have presented 'Outstanding Paper Awards' in four subject categories: Fluid Mechanics; Measurement Science; Precision Measurements; and Sensors and Sensing Systems. 2007 Award Winners—Fluid Mechanics An adaptive sampling and windowing interrogation method in PIV R Theunissen, F Scarano and M L Riethmuller von Karman Institute for Fluid Dynamics, Chaussée de Waterloo 72, 1640 Sint-Genesius Rode, Belgium and Department of Aerospace Engineering, Delft University of Technology, Delft, PO Box 5058, 2600 GB Delft, The Netherlands The co-authored paper [1] has been selected as the Outstanding Paper in Fluid Mechanics for 2007. This paper provides a strategy whereby the placement and the size of the interrogation regions are adapted to the image signal strength (seeding density) and the spatial variations of the velocity magnitudes. Two, quite distinct, test cases demonstrate the efficacy of their method: a shockwave- boundary layer interaction and an aircraft vortex wake. The Selection Committee—Drs T Fansler, J Foss, I Marusic, S Morris, K Okamoto and M Wernet—selected this paper from a strongly competitive shortlist of four candidates. Their selection process was influenced by the perceived utility of the contribution to the numerous investigators who utilize PIV methods. 2007 Award Winners—Measurement Science Broadband single cell impedance spectroscopy using maximum length sequences: theoretical analysis and practical considerations Tao Sun, Shady Gawad, Catia Bernabini, Nicolas G Green and Hywel Morgan

  16. Nonlinear optical thin films

    NASA Technical Reports Server (NTRS)

    Leslie, Thomas M.

    1993-01-01

    A focused approach to development and evaluation of organic polymer films for use in optoelectronics is presented. The issues and challenges that are addressed include: (1) material synthesis, purification, and the tailoring of the material properties; (2) deposition of uniform thin films by a variety of methods; (3) characterization of material physical properties (thermal, electrical, optical, and electro-optical); and (4) device fabrication and testing. Photonic materials, devices, and systems were identified as critical technology areas by the Department of Commerce and the Department of Defense. This approach offers strong integration of basic material issues through engineering applications by the development of materials that can be exploited as the active unit in a variety of polymeric thin film devices. Improved materials were developed with unprecedented purity and stability. The absorptive properties can be tailored and controlled to provide significant improvement in propagation losses and nonlinear performance. Furthermore, the materials were incorporated into polymers that are highly compatible with fabrication and patterning processes for integrated optical devices and circuits. By simultaneously addressing the issues of materials development and characterization, keeping device design and fabrication in mind, many obstacles were overcome for implementation of these polymeric materials and devices into systems. We intend to considerably improve the upper use temperature, poling stability, and compatibility with silicon based devices. The principal device application that was targeted is a linear electro-optic modulation etalon. Organic polymers need to be properly designed and coupled with existing integrated circuit technology to create new photonic devices for optical communication, image processing, other laser applications such as harmonic generation, and eventually optical computing. The progression from microscopic sample to a suitable film

  17. Detection and quantification limits: basic concepts, international harmonization, and outstanding ("low-level") issues.

    PubMed

    Currie, L A

    2004-01-01

    A brief review is given of concepts, basic definitions, and terminology for metrological detection and quantification capabilities, representing harmonized recommendations and norms of the International Union of Pure and Applied Chemistry (IUPAC) and the International Organization for Standardization (ISO), respectively. Treatment of the (low-level) blank and variance function are discussed in some detail, together with special problems arising with detection decisions and the reporting of low-level data. Key references to the international documents follow, as well as specialized references addressing very low-level counting data, skewed environmental blank distributions, and multiple and multivariate detection decisions.

  18. Dynamical systems approaches to nonlinear problems in systems and circuits

    SciTech Connect

    Salam, F.M.A.; Levi, M.L.

    1988-01-01

    Applications of dynamical-systems analysis to nonlinear circuits and physical systems are discussed in reviews and reports. Topics addressed include general analytical methods, general simulation methods, nonlinear circuits and systems in electrical engineering, control systems, solids and vibrations, and mechanical systems. Consideration is given to the applicability of the Mel'nikov method to highly dissipative systems, damping in nonlinear solid mechanics, a three-dimensional rotation instrument for displaying strange attractors, a chaotic saddle catastrophe in forced oscillators, soliton experiments in annular Josephson junctions, local bifurcation control, periodic and chaotic motions of a buckled beam experiencing parametric and external excitation, and robust nonlinear computed torque control for robot manipulators.

  19. The periodic structure of the natural record, and nonlinear dynamics.

    USGS Publications Warehouse

    Shaw, H.R.

    1987-01-01

    This paper addresses how nonlinear dynamics can contribute to interpretations of the geologic record and evolutionary processes. Background is given to explain why nonlinear concepts are important. A resume of personal research is offered to illustrate why I think nonlinear processes fit with observations on geological and cosmological time series data. The fabric of universal periodicity arrays generated by nonlinear processes is illustrated by means of a simple computer mode. I conclude with implications concerning patterns of evolution, stratigraphic boundary events, and close correlations of major geologically instantaneous events (such as impacts or massive volcanic episodes) with any sharply defined boundary in the geologic column. - from Author

  20. Application of nonlinear time series models to driven systems

    SciTech Connect

    Hunter, N.F. Jr.

    1990-01-01

    In our laboratory we have been engaged in an effort to model nonlinear systems using time series methods. Our objectives have been, first, to understand how the time series response of a nonlinear system unfolds as a function of the underlying state variables, second, to model the evolution of the state variables, and finally, to predict nonlinear system responses. We hope to address the relationship between model parameters and system parameters in the near future. Control of nonlinear systems based on experimentally derived parameters is also a planned topic of future research. 28 refs., 15 figs., 2 tabs.

  1. A region addresses patient safety.

    PubMed

    Feinstein, Karen Wolk; Grunden, Naida; Harrison, Edward I

    2002-06-01

    The Pittsburgh Regional Healthcare Initiative (PRHI) is a coalition of 35 hospitals, 4 major insurers, more than 30 major and small-business health care purchasers, dozens of corporate and civic leaders, organized labor, and partnerships with state and federal government all working together to deliver perfect patient care throughout Southwestern Pennsylvania. PRHI believes that in pursuing perfection, many of the challenges facing today's health care delivery system (eg, waste and error in the delivery of care, rising costs, frustration and shortage among clinicians and workers, financial distress, overcapacity, and lack of access to care) will be addressed. PRHI has identified patient safety (nosocomial infections and medication errors) and 5 clinical areas (obstetrics, orthopedic surgery, cardiac surgery, depression, and diabetes) as ideal starting points. In each of these areas of work, PRHI partners have assembled multifacility/multidisciplinary groups charged with defining perfection, establishing region-wide reporting systems, and devising and implementing recommended improvement strategies and interventions. Many design and conceptual elements of the PRHI strategy are adapted from the Toyota Production System and its Pittsburgh derivative, the Alcoa Business System. PRHI is in the proof-of-concept phase of development.

  2. Optimal singular control for nonlinear semistabilisation

    NASA Astrophysics Data System (ADS)

    L'Afflitto, Andrea; Haddad, Wassim M.

    2016-06-01

    The singular optimal control problem for asymptotic stabilisation has been extensively studied in the literature. In this paper, the optimal singular control problem is extended to address a weaker version of closed-loop stability, namely, semistability, which is of paramount importance for consensus control of network dynamical systems. Three approaches are presented to address the nonlinear semistable singular control problem. Namely, a singular perturbation method is presented to construct a state-feedback singular controller that guarantees closed-loop semistability for nonlinear systems. In this approach, we show that for a non-negative cost-to-go function the minimum cost of a nonlinear semistabilising singular controller is lower than the minimum cost of a singular controller that guarantees asymptotic stability of the closed-loop system. In the second approach, we solve the nonlinear semistable singular control problem by using the cost-to-go function to cancel the singularities in the corresponding Hamilton-Jacobi-Bellman equation. For this case, we show that the minimum value of the singular performance measure is zero. Finally, we provide a framework based on the concepts of state-feedback linearisation and feedback equivalence to solve the singular control problem for semistabilisation of nonlinear dynamical systems. For this approach, we also show that the minimum value of the singular performance measure is zero. Three numerical examples are presented to demonstrate the efficacy of the proposed singular semistabilisation frameworks.

  3. Nonlinear Black Phosphorus for Ultrafast Optical Switching

    NASA Astrophysics Data System (ADS)

    Uddin, Siam; Debnath, Pulak C.; Park, Kichul; Song, Yong-Won

    2017-02-01

    The outstanding electronic and optical properties of black phosphorus (BP) in a two-dimensional (2D) but unique single-layer puckered structure have opened intense research interest ranging from fundamental physics to nanoscale applications covering the electronic and optical domains. The direct and controllable electronic bandgap facilitating wide range of tunable optical response coupled with high anisotropic in-plane properties made BP a promising nonlinear optical material for broadband optical applications. Here, we investigate ultrafast optical switching relying on the optical nonlinearity of BP. Wavelength conversion for modulated signals whose frequency reaches up to 20 GHz is realized by four-wave-mixing (FWM) with BP-deposited D-shaped fiber. In the successful demonstration of the FWM based wavelength conversion, performance parameter has been increased up to ~33% after employing BP in the device. It verifies that BP is able to perform efficient optical switching in the evanescent field interaction regime at very high speed. Our results might suggest that BP-based ultra-fast photonics devices could be potentially developed for broadband applications.

  4. Nonlinear Black Phosphorus for Ultrafast Optical Switching

    PubMed Central

    Uddin, Siam; Debnath, Pulak C.; Park, Kichul; Song, Yong-Won

    2017-01-01

    The outstanding electronic and optical properties of black phosphorus (BP) in a two-dimensional (2D) but unique single-layer puckered structure have opened intense research interest ranging from fundamental physics to nanoscale applications covering the electronic and optical domains. The direct and controllable electronic bandgap facilitating wide range of tunable optical response coupled with high anisotropic in-plane properties made BP a promising nonlinear optical material for broadband optical applications. Here, we investigate ultrafast optical switching relying on the optical nonlinearity of BP. Wavelength conversion for modulated signals whose frequency reaches up to 20 GHz is realized by four-wave-mixing (FWM) with BP-deposited D-shaped fiber. In the successful demonstration of the FWM based wavelength conversion, performance parameter has been increased up to ~33% after employing BP in the device. It verifies that BP is able to perform efficient optical switching in the evanescent field interaction regime at very high speed. Our results might suggest that BP-based ultra-fast photonics devices could be potentially developed for broadband applications. PMID:28240276

  5. An address geocoding solution for Chinese cities

    NASA Astrophysics Data System (ADS)

    Zhang, Xuehu; Ma, Haoming; Li, Qi

    2006-10-01

    We introduce the challenges of address geocoding for Chinese cities and present a potential solution along with a prototype system that deal with these challenges by combining and extending current geocoding solutions developed for United States and Japan. The proposed solution starts by separating city addresses into "standard" addresses which meet a predefined address model and non-standard ones. The standard addresses are stored in a structured relational database in their normalized forms, while a selected portion of the non-standard addresses are stored as aliases to the standard addresses. An in-memory address index is then constructed from the address database and serves as the basis for real-time address matching. Test results were obtained from two trials conducted in the city Beijing. On average 80% matching rate were achieved. Possible improvements to the current design are also discussed.

  6. Geometric Structure-Preserving Discretization Schemes for Nonlinear Elasticity

    DTIC Science & Technology

    2015-08-13

    AFRL-AFOSR-VA-TR-2015-0232 Geometric Structure-Preserving Discretization Schemes for Nonlinear Elasticity Arash Yavari GEORGIA TECH RESEARCH...UNIT NUMBER 7.  PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) GEORGIA TECH RESEARCH CORPORATION 505 10TH ST NW ATLANTA, GA 30318-5775 US 8

  7. An alternative approach to characterize nonlinear site effects

    USGS Publications Warehouse

    Zhang, R.R.; Hartzell, S.; Liang, J.; Hu, Y.

    2005-01-01

    This paper examines the rationale of a method of nonstationary processing and analysis, referred to as the Hilbert-Huang transform (HHT), for its application to a recording-based approach in quantifying influences of soil nonlinearity in site response. In particular, this paper first summarizes symptoms of soil nonlinearity shown in earthquake recordings, reviews the Fourier-based approach to characterizing nonlinearity, and offers justifications for the HHT in addressing nonlinearity issues. This study then uses the HHT method to analyze synthetic data and recordings from the 1964 Niigata and 2001 Nisqually earthquakes. In doing so, the HHT-based site response is defined as the ratio of marginal Hilbert amplitude spectra, alternative to the Fourier-based response that is the ratio of Fourier amplitude spectra. With the Fourier-based approach in studies of site response as a reference, this study shows that the alternative HHT-based approach is effective in characterizing soil nonlinearity and nonlinear site response.

  8. The benefits of noise and nonlinearity: Extracting energy from random vibrations

    NASA Astrophysics Data System (ADS)

    Gammaitoni, Luca; Neri, Igor; Vocca, Helios

    2010-10-01

    Nonlinear behavior is the ordinary feature of the vast majority of dynamical systems and noise is commonly present in any finite temperature physical and chemical system. In this article we briefly review the potentially beneficial outcome of the interplay of noise and nonlinearity by addressing the novel field of vibration energy harvesting. The role of nonlinearity in a piezoelectric harvester oscillator dynamics is modeled with nonlinear stochastic differential equation.

  9. Nonlinear rotordynamics analysis

    NASA Technical Reports Server (NTRS)

    Day, W. B.

    1985-01-01

    The special nonlinearities of the Jeffcott equations in rotordynamics are examined. The immediate application of this analysis is directed toward understanding the excessive vibrations recorded in the LOX pump of the SSME during hot firing ground testing. Deadband, side force and rubbing are three possible sources of inducing nonlinearity in the Jeffcott equations. The present analysis initially reduces these problems to the same mathematical description. A special frequency, named the nonlinear natural frequency is defined and used to develop the solutions of the nonlinear Jeffcott equations as asympotic expansions. This nonlinear natural frequency which is the ratio of the cross-stiffness and the damping, plays a major role in determining response frequencies. Numerical solutions are included for comparison with the analysis. Also, nonlinear frequency-response tables are made for a typical range of values.

  10. Principles of Nonlinear Optics

    DTIC Science & Technology

    1989-11-01

    Holography 74 6.2 Semiclassical Analysis 77 7. The Nonlinear Schrodinger Equation and Soliton Propagation 81 8. Conclusion Ancession For 86 ETis -GRA...is analyzed through the nonlinear Schrodinger equation , which is first heuristically derived. The distortionless pulses arising out of a balance...Eq. (71) has the same form as the nonlinear Schrodinger equation (2], (4], [17], (20], which is used to explain soliton propagation through fibers (21

  11. Nonlinear Ship Dynamics

    DTIC Science & Technology

    1992-07-07

    mrtegrating the original governing differential equation. 2. A. H. Nayfeh, " Parametric Identification of Nonlinear Dynamic Systems," Computers...Structures, Vol. 20. No. 1-3. 1985, pp. 487-493. A parametric identification technique that exploits nonlinear resonances and comparisons of the behavior of...617-631. Presentations 1. A. H. Vn’.yfeh, " Parametric Identification of Nonlinear Dynamic Systems," Symposium on Advances and Trends in Structures

  12. Development of a global ocean mercury model with a methylation cycle: Outstanding issues

    NASA Astrophysics Data System (ADS)

    Semeniuk, Kirill; Dastoor, Ashu

    2017-02-01

    We present a newly developed global ocean mercury (Hg) transport and biogeochemistry model and use preanthropogenic equilibrium simulations to highlight physical and chemical processes which reveal significant knowledge gaps that need to be addressed. As with previous 3-D ocean Hg model work we use a bulk chemistry scheme based on particulate organic carbon remineralization. We also include an explicit methylation cycle based on available reaction rates. The methylation to demethylation rate ratio based on various field studies is found to be inconsistent with the concentration ratios measured in the Southern Ocean around Antarctica and in the Arctic. There is also model-measurement disagreement in the old waters of the tropical and North Pacific Ocean. The model produces an intermediate water maximum in total Hg in this region reflecting the higher age of water which is absent in observations. The model also underestimates total Hg concentrations in the deepest waters in this region. These disagreements in depth profile shape point to an inadequate representation of scavenging and sedimentation and possibly seabed emission or remobilization of Hg. In addition, the total Hg distribution differences compared to previous model work reflect sensitivity to ocean model transport characteristics and in particular the tracer diffusion. The residence time of Hg in the global ocean and the surface evasion flux of elemental Hg is sensitive to such model aspects. We find a global ocean Hg turnover time against sediment burial to be about 1100 years which is within the range of previous studies.

  13. Nonlinear magnetic metamaterials.

    PubMed

    Shadrivov, Ilya V; Kozyrev, Alexander B; van der Weide, Daniel W; Kivshar, Yuri S

    2008-12-08

    We study experimentally nonlinear tunable magnetic metamaterials operating at microwave frequencies. We fabricate the nonlinear metamaterial composed of double split-ring resonators where a varactor diode is introduced into each resonator so that the magnetic resonance can be tuned dynamically by varying the input power. We demonstrate that at higher powers the transmission of the metamaterial becomes power-dependent and, as a result, such metamaterial can demonstrate various nonlinear properties. In particular, we study experimentally the power-dependent shift of the transmission band and demonstrate nonlinearity-induced enhancement (or suppression) of wave transmission.

  14. Nonlinearity-reduced interferometer

    NASA Astrophysics Data System (ADS)

    Wu, Chien-ming

    2007-12-01

    Periodic nonlinearity is a systematic error limiting the accuracy of displacement measurements at the nanometer level. It results from many causes such as the frequency mixing, polarization mixing, polarization-frequency mixing, and the ghost reflections. An interferometer having accuracy in displacement measurement of less than one-nanometer is necessary in nanometrology. To meet the requirement, the periodic nonlinearity should be less than deep sub-nanometer. In this paper, a nonlinearity-reduced interferometry has been proposed. Both the linear- and straightness-interferometer were tested. The developed interferometer demonstrated of a residual nonlinearity less than 25 pm.

  15. Adapting a truly nonlinear filter to the ocean acoustic inverse problem

    NASA Astrophysics Data System (ADS)

    Ganse, Andrew A.; Odom, Robert I.

    2005-04-01

    Nonlinear inverse problems including the ocean acoustic problem have been solved by Monte Carlo, locally-linear, and filter based techniques such as the Extended Kalman Filter (EKF). While these techniques do provide statistical information about the solution (e.g., mean and variance), each suffers from inherent limitations in their approach to nonlinear problems. Monte Carlo techniques are expensive to compute and do not contribute to intuitive interpretation of a problem, and locally-linear techniques (including the EKF) are limited by the multimodal objective landscape of nonlinear problems. A truly nonlinear filter, based on recent work in nonlinear tracking, estimates state information for a nonlinear problem in continual measurement updates and is adapted to solving nonlinear inverse problems. Additional terms derived from the system's state PDF are added to the mean and covariance of the solution to address the nonlinearities of the problem, and overall the technique offers improved performance in nonlinear inversion. [Work supported by ONR.

  16. 16 CFR 0.2 - Official address.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Official address. The principal office of the Commission is at Washington, DC. All communications to the Commission should be addressed to the Federal Trade Commission, 600 Pennsylvania Avenue, NW, Washington,...

  17. 16 CFR 0.2 - Official address.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Official address. The principal office of the Commission is at Washington, DC. All communications to the Commission should be addressed to the Federal Trade Commission, 600 Pennsylvania Avenue, NW, Washington,...

  18. 16 CFR 0.2 - Official address.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Official address. The principal office of the Commission is at Washington, DC. All communications to the Commission should be addressed to the Federal Trade Commission, 600 Pennsylvania Avenue, NW, Washington,...

  19. 47 CFR 97.23 - Mailing address.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Mailing address. 97.23 Section 97.23 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO... name and mailing address. The mailing address must be in an area where the amateur service is...

  20. 47 CFR 97.23 - Mailing address.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Mailing address. 97.23 Section 97.23 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO... name and mailing address. The mailing address must be in an area where the amateur service is...

  1. 47 CFR 97.23 - Mailing address.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Mailing address. 97.23 Section 97.23 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO... name and mailing address. The mailing address must be in an area where the amateur service is...

  2. 47 CFR 97.23 - Mailing address.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Mailing address. 97.23 Section 97.23 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO... name and mailing address. The mailing address must be in an area where the amateur service is...

  3. 47 CFR 97.23 - Mailing address.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Mailing address. 97.23 Section 97.23 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO... name and mailing address. The mailing address must be in an area where the amateur service is...

  4. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Correspondence addresses. 41... Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in an application... correspondence in an application or a patent involved in an appeal to the Board for which an address is...

  5. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Correspondence addresses. 41... Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in an application... correspondence in an application or a patent involved in an appeal to the Board for which an address is...

  6. 47 CFR 13.10 - Licensee address.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Licensee address. 13.10 Section 13.10 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMERCIAL RADIO OPERATORS General § 13.10 Licensee address. In accordance with § 1.923 of this chapter all applications must specify an address where...

  7. 32 CFR 516.7 - Mailing addresses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Mailing addresses. 516.7 Section 516.7 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS LITIGATION General § 516.7 Mailing addresses. Mailing addresses for organizations referenced...

  8. Spacecraft nonlinear control

    NASA Technical Reports Server (NTRS)

    Sheen, Jyh-Jong; Bishop, Robert H.

    1992-01-01

    The feedback linearization technique is applied to the problem of spacecraft attitude control and momentum management with control moment gyros (CMGs). The feedback linearization consists of a coordinate transformation, which transforms the system to a companion form, and a nonlinear feedback control law to cancel the nonlinear dynamics resulting in a linear equivalent model. Pole placement techniques are then used to place the closed-loop poles. The coordinate transformation proposed here evolves from three output functions of relative degree four, three, and two, respectively. The nonlinear feedback control law is presented. Stability in a neighborhood of a controllable torque equilibrium attitude (TEA) is guaranteed and this fact is demonstrated by the simulation results. An investigation of the nonlinear control law shows that singularities exist in the state space outside the neighborhood of the controllable TEA. The nonlinear control law is simplified by a standard linearization technique and it is shown that the linearized nonlinear controller provides a natural way to select control gains for the multiple-input, multiple-output system. Simulation results using the linearized nonlinear controller show good performance relative to the nonlinear controller in the neighborhood of the TEA.

  9. Optically Nonlinear Polymeric Materials.

    DTIC Science & Technology

    1983-01-01

    optical chromophores into the hydrophobic portions of the polymer, second order . ,nonlinear optical effects may be obtained. Experimental 01 0...8217V cinnamaldehyde , giving the polymer shown in Figure 3. This chromophore should have greater optical nonlinearity because of its better electron

  10. Nonlinear Optics and Applications

    NASA Technical Reports Server (NTRS)

    Abdeldayem, Hossin A. (Editor); Frazier, Donald O. (Editor)

    2007-01-01

    Nonlinear optics is the result of laser beam interaction with materials and started with the advent of lasers in the early 1960s. The field is growing daily and plays a major role in emerging photonic technology. Nonlinear optics play a major role in many of the optical applications such as optical signal processing, optical computers, ultrafast switches, ultra-short pulsed lasers, sensors, laser amplifiers, and many others. This special review volume on Nonlinear Optics and Applications is intended for those who want to be aware of the most recent technology. This book presents a survey of the recent advances of nonlinear optical applications. Emphasis will be on novel devices and materials, switching technology, optical computing, and important experimental results. Recent developments in topics which are of historical interest to researchers, and in the same time of potential use in the fields of all-optical communication and computing technologies, are also included. Additionally, a few new related topics which might provoke discussion are presented. The book includes chapters on nonlinear optics and applications; the nonlinear Schrodinger and associated equations that model spatio-temporal propagation; the supercontinuum light source; wideband ultrashort pulse fiber laser sources; lattice fabrication as well as their linear and nonlinear light guiding properties; the second-order EO effect (Pockels), the third-order (Kerr) and thermo-optical effects in optical waveguides and their applications in optical communication; and, the effect of magnetic field and its role in nonlinear optics, among other chapters.

  11. Nonlinear Maneuver Autopilot

    NASA Technical Reports Server (NTRS)

    Menon, P. K. A.; Badgett, M. E.; Walker, R. A.

    1992-01-01

    Trajectory-control laws based on singular-perturbation theory and nonlinear dynamical modeling. Nonlinear maneuver autopilot commands flight-test trajectories of F-15 airplane. Underlying theory of controller enables separation of variables processed in fast and slow control loops, reducing amount of computation required.

  12. Lasers for nonlinear microscopy.

    PubMed

    Wise, Frank

    2013-03-01

    Various versions of nonlinear microscopy are revolutionizing the life sciences, almost all of which are made possible because of the development of ultrafast lasers. In this article, the main properties and technical features of short-pulse lasers used in nonlinear microscopy are summarized. Recent research results on fiber lasers that will impact future instruments are also discussed.

  13. Control of terahertz nonlinear transmission with electrically gated graphene metadevices

    NASA Astrophysics Data System (ADS)

    Choi, Hyun Joo; Baek, In Hyung; Kang, Bong Joo; Kim, Hyeon-Don; Oh, Sang Soon; Hamm, Joachim M.; Pusch, Andreas; Park, Jagang; Lee, Kanghee; Son, Jaehyeon; Jeong, Young U. K.; Hess, Ortwin; Rotermund, Fabian; Min, Bumki

    2017-02-01

    Graphene, which is a two-dimensional crystal of carbon atoms arranged in a hexagonal lattice, has attracted a great amount of attention due to its outstanding mechanical, thermal and electronic properties. Moreover, graphene shows an exceptionally strong tunable light-matter interaction that depends on the Fermi level - a function of chemical doping and external gate voltage - and the electromagnetic resonance provided by intentionally engineered structures. In the optical regime, the nonlinearities of graphene originated from the Pauli blocking have already been exploited for mode-locking device applications in ultrafast laser technology, whereas nonlinearities in the terahertz regime, which arise from a reduction in conductivity due to carrier heating, have only recently been confirmed experimentally. Here, we investigated two key factors for controlling nonlinear interactions of graphene with an intense terahertz field. The induced transparencies of graphene can be controlled effectively by engineering meta-atoms and/or changing the number of charge carriers through electrical gating. Additionally, nonlinear phase changes of the transmitted terahertz field can be observed by introducing the resonances of the meta-atoms.

  14. Control of terahertz nonlinear transmission with electrically gated graphene metadevices.

    PubMed

    Choi, Hyun Joo; Baek, In Hyung; Kang, Bong Joo; Kim, Hyeon-Don; Oh, Sang Soon; Hamm, Joachim M; Pusch, Andreas; Park, Jagang; Lee, Kanghee; Son, Jaehyeon; Jeong, Young U K; Hess, Ortwin; Rotermund, Fabian; Min, Bumki

    2017-02-20

    Graphene, which is a two-dimensional crystal of carbon atoms arranged in a hexagonal lattice, has attracted a great amount of attention due to its outstanding mechanical, thermal and electronic properties. Moreover, graphene shows an exceptionally strong tunable light-matter interaction that depends on the Fermi level - a function of chemical doping and external gate voltage - and the electromagnetic resonance provided by intentionally engineered structures. In the optical regime, the nonlinearities of graphene originated from the Pauli blocking have already been exploited for mode-locking device applications in ultrafast laser technology, whereas nonlinearities in the terahertz regime, which arise from a reduction in conductivity due to carrier heating, have only recently been confirmed experimentally. Here, we investigated two key factors for controlling nonlinear interactions of graphene with an intense terahertz field. The induced transparencies of graphene can be controlled effectively by engineering meta-atoms and/or changing the number of charge carriers through electrical gating. Additionally, nonlinear phase changes of the transmitted terahertz field can be observed by introducing the resonances of the meta-atoms.

  15. Control of terahertz nonlinear transmission with electrically gated graphene metadevices

    PubMed Central

    Choi, Hyun Joo; Baek, In Hyung; Kang, Bong Joo; Kim, Hyeon-Don; Oh, Sang Soon; Hamm, Joachim M.; Pusch, Andreas; Park, Jagang; Lee, Kanghee; Son, Jaehyeon; Jeong, Young U. k.; Hess, Ortwin; Rotermund, Fabian; Min, Bumki

    2017-01-01

    Graphene, which is a two-dimensional crystal of carbon atoms arranged in a hexagonal lattice, has attracted a great amount of attention due to its outstanding mechanical, thermal and electronic properties. Moreover, graphene shows an exceptionally strong tunable light-matter interaction that depends on the Fermi level - a function of chemical doping and external gate voltage - and the electromagnetic resonance provided by intentionally engineered structures. In the optical regime, the nonlinearities of graphene originated from the Pauli blocking have already been exploited for mode-locking device applications in ultrafast laser technology, whereas nonlinearities in the terahertz regime, which arise from a reduction in conductivity due to carrier heating, have only recently been confirmed experimentally. Here, we investigated two key factors for controlling nonlinear interactions of graphene with an intense terahertz field. The induced transparencies of graphene can be controlled effectively by engineering meta-atoms and/or changing the number of charge carriers through electrical gating. Additionally, nonlinear phase changes of the transmitted terahertz field can be observed by introducing the resonances of the meta-atoms. PMID:28216677

  16. Augmented nonlinear differentiator design and application to nonlinear uncertain systems.

    PubMed

    Shao, Xingling; Liu, Jun; Li, Jie; Cao, Huiliang; Shen, Chong; Zhang, Xiaoming

    2017-03-01

    In this paper, an augmented nonlinear differentiator (AND) based on sigmoid function is developed to calculate the noise-less time derivative under noisy measurement condition. The essential philosophy of proposed AND in achieving high attenuation of noise effect is established by expanding the signal dynamics with extra state variable representing the integrated noisy measurement, then with the integral of measurement as input, the augmented differentiator is formulated to improve the estimation quality. The prominent advantages of the present differentiation technique are: (i) better noise suppression ability can be achieved without appreciable delay; (ii) the improved methodology can be readily extended to construct augmented high-order differentiator to obtain multiple derivatives. In addition, the convergence property and robustness performance against noises are investigated via singular perturbation theory and describing function method, respectively. Also, comparison with several classical differentiators is given to illustrate the superiority of AND in noise suppression. Finally, the robust control problems of nonlinear uncertain systems, including a numerical example and a mass spring system, are addressed to demonstrate the effectiveness of AND in precisely estimating the disturbance and providing the unavailable differential estimate to implement output feedback based controller.

  17. Nonlinear Dynamics of Single Bunch Instability

    SciTech Connect

    Stupakov, G.V.; Breizman, B.N.; Pekker, M.S.; /Texas U.

    2011-09-09

    A nonlinear equation is derived that governs the evolution of the amplitude of unstable oscillations with account of quantum diffusion effects due to the synchrotron radiation. Numerical solutions to this equation predict a variety of possible scenarios of nonlinear evolution of the instability some of which are in good qualitative agreement with experimental observations. Microwave single bunch instability in circular accelerators has been observed in many machines. The instability usually arises when the number of particles in the bunch exceeds some critical value, Nc, which varies depending on the parameters of the accelerating regime. Recent observations on the SLC damping rings at SLAC with a new low-impedance vacuum chamber revealed new interesting features of the instability. In some cases, after initial exponential growth, the instability eventually saturated at a level that remained constant through the accumulation cycle. In other regimes, relaxation-type oscillations were measured in nonlinear phase of the instability. In many cases, the instability was characterized by a frequency close to the second harmonic of the synchrotron oscillations. Several attempts have been made to address the nonlinear stage of the instability based on either computer simulations or some specific assumptions regarding the structure of the unstable mode. An attempt of a more general consideration of the problem is carried out in this paper. We adopt an approach recently developed in plasma physics for analysis of nonlinear behavior of weakly unstable modes in dynamic systems. Assuming that the growth rate of the instability is much smaller than its frequency, we find a time dependent solution to Vlasov equation and derive an equation for the complex amplitude of the oscillations valid in the nonlinear regime. Numerical solutions to this equation predict a variety of possible scenarios of nonlinear evolution of the instability some of which are in good qualitative agreement

  18. Nonlinear Fourier analysis with cnoidal waves

    SciTech Connect

    Osborne, A.R.

    1996-12-31

    Fourier analysis is one of the most useful tools to the ocean engineer. The approach allows one to analyze wave data and thereby to describe a dynamical motion in terms of a linear superposition of ordinary sine waves. Furthermore, the Fourier technique allows one to compute the response function of a fixed or floating structure: each sine wave in the wave or force spectrum yields a sine wave in the response spectrum. The counting of fatigue cycles is another area where the predictable oscillations of sine waves yield procedures for the estimation of the fatigue life of structures. The ocean environment, however, is a source of a number of nonlinear effects which must also be included in structure design. Nonlinearities in ocean waves deform the sinusoidal shapes into other kinds of waves such as the Stokes wave, cnoidal wave or solitary wave. A key question is: Does there exist a generalization of linear Fourier analysis which uses nonlinear basis functions rather than the familiar sine waves? Herein addresses the dynamics of nonlinear wave motion in shallow water where the basis functions are cnoidal waves and discuss nonlinear Fourier analysis in terms of a linear superposition of cnoidal waves plus their mutual nonlinear interactions. He gives a number of simple examples of nonlinear Fourier wave motion and then analyzes an actual surface-wave time series obtained on an offshore platform in the Adriatic Sea. Finally, he briefly discusses application of the cnoidal wave spectral approach to the computation of the frequency response function of a floating vessel. The results given herein will prove useful in future engineering studies for the design of fixed, floating and complaint offshore structures.

  19. On Dynamic Nonlinear Elasticity and Small Strain

    NASA Astrophysics Data System (ADS)

    Johnson, P. A.; Sutin, A.; Guyer, R. A.; Tencate, J. A.

    2002-12-01

    We are addressing the question of whether or not there is a threshold strain behavior where anomalous nonlinear fast dynamics (ANFD) commences in rock and other similar solids, or if the elastic nonlinearity persists to the smallest measurable values. In qualitative measures of many rock types and other materials that behave in the same manner, we have not observed a threshold; however the only careful, small strain level study conducted under controlled conditions that we are aware of is that of TenCate et al. in Berea sandstone (Phys. Rev. Lett. 85, 1020-1024 (2000)). This work indicates that in Berea sandstone, the elastic nonlinearity persists to the minimum measured strains of at least 10-8. Recently, we have begun controlled experiments in other materials that exhibit ANFD in order to see whether or not they behave as Berea sandstone does. We are employing Young's mode resonance to study resonance peak shift and amplitude variations as a function of drive level and detected strain level. In this type of experiment, the time average amplitude is recorded as the sample is driven by a continuous wave source from below to above the fundamental mode resonance. The drive level is increased, and the measurement is repeated progressively over larger and larger drive levels. Experiments are conducted at ambient pressure. Pure alumina ceramic is a material that is highly, elastically-nonlinear and nonporous, and therefore the significant influence of relative humidity on elastic nonlinear response that rock suffers is avoided. Temperature is carefully monitored. Measurements on pure alumina ceramic show that, like Berea sandstone, there is no threshold of elastic nonlinearity within our measurement capability. We are now studying other solids that exhibit ANFD including rock and mixed phase metal. These results indicate that elastic nonlinearity influences all elastic measurments on these solids including modulus and Q at ambient conditions. There appears to be no

  20. Parametric Identification of Nonlinear Dynamical Systems

    NASA Technical Reports Server (NTRS)

    Feeny, Brian

    2002-01-01

    In this project, we looked at the application of harmonic balancing as a tool for identifying parameters (HBID) in a nonlinear dynamical systems with chaotic responses. The main idea is to balance the harmonics of periodic orbits extracted from measurements of each coordinate during a chaotic response. The periodic orbits are taken to be approximate solutions to the differential equations that model the system, the form of the differential equations being known, but with unknown parameters to be identified. Below we summarize the main points addressed in this work. The details of the work are attached as drafts of papers, and a thesis, in the appendix. Our study involved the following three parts: (1) Application of the harmonic balance to a simulation case in which the differential equation model has known form for its nonlinear terms, in contrast to a differential equation model which has either power series or interpolating functions to represent the nonlinear terms. We chose a pendulum, which has sinusoidal nonlinearities; (2) Application of the harmonic balance to an experimental system with known nonlinear forms. We chose a double pendulum, for which chaotic response were easily generated. Thus we confronted a two-degree-of-freedom system, which brought forth challenging issues; (3) A study of alternative reconstruction methods. The reconstruction of the phase space is necessary for the extraction of periodic orbits from the chaotic responses, which is needed in this work. Also, characterization of a nonlinear system is done in the reconstructed phase space. Such characterizations are needed to compare models with experiments. Finally, some nonlinear prediction methods can be applied in the reconstructed phase space. We developed two reconstruction methods that may be considered if the common method (method of delays) is not applicable.

  1. Nonlinear cochlear mechanics.

    PubMed

    Zweig, George

    2016-05-01

    An earlier paper characterizing the linear mechanical response of the organ of Corti [J. Acoust. Soc. Am. 138, 1102-1121 (2015)] is extended to the nonlinear domain. Assuming the existence of nonlinear oscillators nonlocally coupled through the pressure they help create, the oscillator equations are derived and examined when the stimuli are modulated tones and clicks. The nonlinearities are constrained by the requirements of oscillator stability and the invariance of zero crossings in the click response to changes in click amplitude. The nonlinear oscillator equations for tones are solved in terms of the fluid pressure that drives them, and its time derivative, presumably a proxy for forces created by outer hair cells. The pressure equation is reduced to quadrature, the integrand depending on the oscillators' responses. The resulting nonlocally coupled nonlinear equations for the pressure, and oscillator amplitudes and phases, are solved numerically in terms of the fluid pressure at the stapes. Methods for determining the nonlinear damping directly from measurements are described. Once the oscillators have been characterized from their tone and click responses, the mechanical response of the cochlea to natural sounds may be computed numerically. Signal processing inspired by cochlear mechanics opens up a new area of nonlocal nonlinear time-frequency analysis.

  2. Nonlinear conductance in a ballistic Aharonov-Bohm ring.

    PubMed

    Hernández, Alexis R; Lewenkopf, Caio H

    2009-10-16

    The nonlinear electronic transport properties of a ballistic Aharonov-Bohm ring are investigated. It is demonstrated how the electronic interaction breaks the phase rigidity in a two-probe mesoscopic device as the voltage bias is increased. The possibility of studying interference effects in the nonlinear regime is addressed. The occurrence of magnetic field symmetries in higher order conductance coefficients is analyzed. The results are compared with recent experimental data.

  3. Metamaterials with conformational nonlinearity

    PubMed Central

    Lapine, Mikhail; Shadrivov, Ilya V.; Powell, David A.; Kivshar, Yuri S.

    2011-01-01

    Within a decade of fruitful development, metamaterials became a prominent area of research, bridging theoretical and applied electrodynamics, electrical engineering and material science. Being man-made structures, metamaterials offer a particularly useful playground to develop interdisciplinary concepts. Here we demonstrate a novel principle in metamaterial assembly which integrates electromagnetic, mechanical, and thermal responses within their elements. Through these mechanisms, the conformation of the meta-molecules changes, providing a dual mechanism for nonlinearity and offering nonlinear chirality. Our proposal opens a wide road towards further developments of nonlinear metamaterials and photonic structures, adding extra flexibility to their design and control. PMID:22355655

  4. Nonlinear ordinary difference equations

    NASA Technical Reports Server (NTRS)

    Caughey, T. K.

    1979-01-01

    Future space vehicles will be relatively large and flexible, and active control will be necessary to maintain geometrical configuration. While the stresses and strains in these space vehicles are not expected to be excessively large, their cumulative effects will cause significant geometrical nonlinearities to appear in the equations of motion, in addition to the nonlinearities caused by material properties. Since the only effective tool for the analysis of such large complex structures is the digital computer, it will be necessary to gain a better understanding of the nonlinear ordinary difference equations which result from the time discretization of the semidiscrete equations of motion for such structures.

  5. Nonlinear mixing of laser generated narrowband Rayleigh surface waves

    NASA Astrophysics Data System (ADS)

    Bakre, Chaitanya; Rajagopal, Prabhu; Balasubramaniam, Krishnan

    2017-02-01

    This research presents the nonlinear mixing technique of two co-directionally travelling Rayleigh surface waves generated and detected using laser ultrasonics. The optical generation of Rayleigh waves on the specimen is obtained by shadow mask method. In conventional nonlinear measurements, the inherently small higher harmonics are greatly influenced by the nonlinearities caused by coupling variabilities and surface roughness between the transducer and specimen interface. The proposed technique is completely contactless and it should be possible to eliminate this problem. Moreover, the nonlinear mixing phenomenon yields not only the second harmonics, but also the sum and difference frequency components, which can be used to measure the acoustic nonlinearity of the specimen. In this paper, we will be addressing the experimental configurations for this technique. The proposed technique is validated experimentally on Aluminum 7075 alloy specimen.

  6. Novel Duplicate Address Detection with Hash Function

    PubMed Central

    Song, GuangJia; Ji, ZhenZhou

    2016-01-01

    Duplicate address detection (DAD) is an important component of the address resolution protocol (ARP) and the neighbor discovery protocol (NDP). DAD determines whether an IP address is in conflict with other nodes. In traditional DAD, the target address to be detected is broadcast through the network, which provides convenience for malicious nodes to attack. A malicious node can send a spoofing reply to prevent the address configuration of a normal node, and thus, a denial-of-service attack is launched. This study proposes a hash method to hide the target address in DAD, which prevents an attack node from launching destination attacks. If the address of a normal node is identical to the detection address, then its hash value should be the same as the “Hash_64” field in the neighboring solicitation message. Consequently, DAD can be successfully completed. This process is called DAD-h. Simulation results indicate that address configuration using DAD-h has a considerably higher success rate when under attack compared with traditional DAD. Comparative analysis shows that DAD-h does not require third-party devices and considerable computing resources; it also provides a lightweight security resolution. PMID:26991901

  7. Superconducting qubits can be coupled and addressed as trapped ions

    NASA Astrophysics Data System (ADS)

    Liu, Y. X.; Wei, L. F.; Johansson, J. R.; Tsai, J. S.; Nori, F.

    2009-03-01

    Exploiting the intrinsic nonlinearity of superconducting Josephson junctions, we propose a scalable circuit with superconducting qubits (SCQs) which is very similar to the successful one now being used for trapped ions. The SCQs are coupled to the ``vibrational'' mode provided by a superconducting LC circuit or its equivalent (e.g., a superconducting quantum interference device). Both single-qubit rotations and qubit-LC-circuit couplings and/or decouplings can be controlled by the frequencies of the time-dependent magnetic fluxes. The circuit is scalable since the qubit-qubit interactions, mediated by the LC circuit, can be selectively performed, and the information transfer can be realized in a controllable way. [4pt] Y.X. Liu, L.F. Wei, J.R. Johansson, J.S. Tsai, F. Nori, Superconducting qubits can be coupled and addressed as trapped ions, Phys. Rev. B 76, 144518 (2007). URL: http://link.aps.org/abstract/PRB/v76/e144518

  8. Nonlinear optomechanical pressure

    NASA Astrophysics Data System (ADS)

    Conti, Claudio; Boyd, Robert

    2014-03-01

    A transparent material exhibits ultrafast optical nonlinearity and is subject to optical pressure if irradiated by a laser beam. However, the effect of nonlinearity on optical pressure is often overlooked, even if a nonlinear optical pressure may be potentially employed in many applications, such as optical manipulation, biophysics, cavity optomechanics, quantum optics, and optical tractors, and is relevant in fundamental problems such as the Abraham-Minkoswky dilemma or the Casimir effect. Here, we show that an ultrafast nonlinear polarization gives indeed a contribution to the optical pressure that also is negative in certain spectral ranges; the theoretical analysis is confirmed by first-principles simulations. An order-of-magnitude estimate shows that the effect can be observable by measuring the deflection of a membrane made by graphene.

  9. Nonlinear Dynamics in Cardiology

    PubMed Central

    Krogh-Madsen, Trine; Christini, David J.

    2013-01-01

    The dynamics of many cardiac arrhythmias, as well as the nature of transitions between different heart rhythms, have long been considered evidence of nonlinear phenomena playing a direct role in cardiac arrhythmogenesis. In most types of cardiac disease, the pathology develops slowly and gradually, often over many years. In contrast, arrhythmias often occur suddenly. In nonlinear systems, sudden changes in qualitative dynamics can, counter-intuitively, result from a gradual change in a system parameter –this is known as a bifurcation. Here, we review how nonlinearities in cardiac electrophysiology influence normal and abnormal rhythms and how bifurcations change the dynamics. In particular, we focus on the many recent developments in computational modeling at the cellular level focused on intracellular calcium dynamics. We discuss two areas where recent experimental and modeling work have suggested the importance of nonlinearities in calcium dynamics: repolarization alternans and pacemaker cell automaticity. PMID:22524390

  10. Goos-Hänchen shifts of Helmholtz solitons at nonlocal nonlinear interfaces

    NASA Astrophysics Data System (ADS)

    Zhiwei, Shi; Jing, Xue; Jilong, Chen; Yang, Li; Huagang, Li

    2015-02-01

    We address the nonlinear Goos-Hänchen shift of Helmholtz solitons at a nonlocal nonlinear interface between a Kerr medium and a nonlocal nonlinear medium. Based on the framework of the Helmholtz theory, we have demonstrated that the Goos-Hänchen shift depends on the angle of the incidence, the linear and nonlinear refractive index mismatch at the interface, the nonparaxial parameter and the degree of nonlocality. Interestingly, internal and external refraction can be introduced when the nonlinear refractive index mismatch is greater than a threshold value. The total reflection will occur when the degree of nonlocality exceeds a value.

  11. Adaptive and Nonlinear Control

    DTIC Science & Technology

    1992-02-29

    in [22], we also applied the concept of zero dynamics to the problem of exact linearization of a nonlinear control system by dynamic feedback. Exact ...nonlinear systems, although it was well-known that the conditions for exact linearization are very stringent and consequently do not apply to a broad...29th IEEE Conference n Decision and Control, Invited Paper delivered by Dr. Gilliam. Exact Linearization of Zero Dynamics, 29th IEEE Conference on

  12. Perturbed nonlinear differential equations

    NASA Technical Reports Server (NTRS)

    Proctor, T. G.

    1974-01-01

    For perturbed nonlinear systems, a norm, other than the supremum norm, is introduced on some spaces of continuous functions. This makes possible the study of new types of behavior. A study is presented on a perturbed nonlinear differential equation defined on a half line, and the existence of a family of solutions with special boundedness properties is established. The ideas developed are applied to the study of integral manifolds, and examples are given.

  13. A geometrical approach to control and controllability of nonlinear dynamical networks

    PubMed Central

    Wang, Le-Zhi; Su, Ri-Qi; Huang, Zi-Gang; Wang, Xiao; Wang, Wen-Xu; Grebogi, Celso; Lai, Ying-Cheng

    2016-01-01

    In spite of the recent interest and advances in linear controllability of complex networks, controlling nonlinear network dynamics remains an outstanding problem. Here we develop an experimentally feasible control framework for nonlinear dynamical networks that exhibit multistability. The control objective is to apply parameter perturbation to drive the system from one attractor to another, assuming that the former is undesired and the latter is desired. To make our framework practically meaningful, we consider restricted parameter perturbation by imposing two constraints: it must be experimentally realizable and applied only temporarily. We introduce the concept of attractor network, which allows us to formulate a quantifiable controllability framework for nonlinear dynamical networks: a network is more controllable if the attractor network is more strongly connected. We test our control framework using examples from various models of experimental gene regulatory networks and demonstrate the beneficial role of noise in facilitating control. PMID:27076273

  14. PREFACE: Nonlinearity and Geometry: connections with integrability Nonlinearity and Geometry: connections with integrability

    NASA Astrophysics Data System (ADS)

    Cieslinski, Jan L.; Ferapontov, Eugene V.; Kitaev, Alexander V.; Nimmo, Jonathan J. C.

    2009-10-01

    Geometric ideas are present in many areas of modern theoretical physics and they are usually associated with the presence of nonlinear phenomena. Integrable nonlinear systems play a prime role both in geometry itself and in nonlinear physics. One can mention general relativity, exact solutions of the Einstein equations, string theory, Yang-Mills theory, instantons, solitons in nonlinear optics and hydrodynamics, vortex dynamics, solvable models of statistical physics, deformation quantization, and many others. Soliton theory now forms a beautiful part of mathematics with very strong physical motivations and numerous applications. Interactions between mathematics and physics associated with integrability issues are very fruitful and stimulating. For instance, spectral theories of linear quantum mechanics turned out to be crucial for studying nonlinear integrable systems. The modern theory of integrable nonlinear partial differential and difference equations, or the `theory of solitons', is deeply rooted in the achievements of outstanding geometers of the end of the 19th and the beginning of the 20th century, such as Luigi Bianchi (1856-1928) and Jean Gaston Darboux (1842-1917). Transformations of surfaces and explicit constructions developed by `old' geometers were often rediscovered or reinterpreted in a modern framework. The great progress of recent years in so-called discrete geometry is certainly due to strong integrable motivations. A very remarkable feature of the results of the classical integrable geometry is the quite natural (although nontrivial) possibility of their discretization. This special issue is dedicated to Jean Gaston Darboux and his pioneering role in the development of the geometric ideas of modern soliton theory. The most famous aspects of his work are probably Darboux transformations and triply orthogonal systems of surfaces, whose role in modern mathematical physics cannot be overestimated. Indeed, Darboux transformations play a central

  15. Robust Nonlinear Neural Codes

    NASA Astrophysics Data System (ADS)

    Yang, Qianli; Pitkow, Xaq

    2015-03-01

    Most interesting natural sensory stimuli are encoded in the brain in a form that can only be decoded nonlinearly. But despite being a core function of the brain, nonlinear population codes are rarely studied and poorly understood. Interestingly, the few existing models of nonlinear codes are inconsistent with known architectural features of the brain. In particular, these codes have information content that scales with the size of the cortical population, even if that violates the data processing inequality by exceeding the amount of information entering the sensory system. Here we provide a valid theory of nonlinear population codes by generalizing recent work on information-limiting correlations in linear population codes. Although these generalized, nonlinear information-limiting correlations bound the performance of any decoder, they also make decoding more robust to suboptimal computation, allowing many suboptimal decoders to achieve nearly the same efficiency as an optimal decoder. Although these correlations are extremely difficult to measure directly, particularly for nonlinear codes, we provide a simple, practical test by which one can use choice-related activity in small populations of neurons to determine whether decoding is suboptimal or optimal and limited by correlated noise. We conclude by describing an example computation in the vestibular system where this theory applies. QY and XP was supported by a grant from the McNair foundation.

  16. Nonlinear systems in medicine.

    PubMed Central

    Higgins, John P.

    2002-01-01

    Many achievements in medicine have come from applying linear theory to problems. Most current methods of data analysis use linear models, which are based on proportionality between two variables and/or relationships described by linear differential equations. However, nonlinear behavior commonly occurs within human systems due to their complex dynamic nature; this cannot be described adequately by linear models. Nonlinear thinking has grown among physiologists and physicians over the past century, and non-linear system theories are beginning to be applied to assist in interpreting, explaining, and predicting biological phenomena. Chaos theory describes elements manifesting behavior that is extremely sensitive to initial conditions, does not repeat itself and yet is deterministic. Complexity theory goes one step beyond chaos and is attempting to explain complex behavior that emerges within dynamic nonlinear systems. Nonlinear modeling still has not been able to explain all of the complexity present in human systems, and further models still need to be refined and developed. However, nonlinear modeling is helping to explain some system behaviors that linear systems cannot and thus will augment our understanding of the nature of complex dynamic systems within the human body in health and in disease states. PMID:14580107

  17. Pescara benchmarks: nonlinear identification

    NASA Astrophysics Data System (ADS)

    Gandino, E.; Garibaldi, L.; Marchesiello, S.

    2011-07-01

    Recent nonlinear methods are suitable for identifying large systems with lumped nonlinearities, but in practice most structural nonlinearities are distributed and an ideal nonlinear identification method should cater for them as well. In order to extend the current NSI method to be applied also on realistic large engineering structures, a modal counterpart of the method is proposed in this paper. The modal NSI technique is applied on one of the reinforced concrete beams that have been tested in Pescara, under the project titled "Monitoring and diagnostics of railway bridges by means of the analysis of the dynamic response due to train crossing", financed by Italian Ministry of Research. The beam showed a softening nonlinear behaviour, so that the nonlinearity concerning the first mode is characterized and its force contribution is quantified. Moreover, estimates for the modal parameters are obtained and the model is validated by comparing the measured and the reconstructed output. The identified estimates are also used to accurately predict the behaviour of the same beam, when subject to different initial conditions.

  18. 49 CFR 1102.1 - How addressed.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false How addressed. 1102.1 Section 1102.1 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION RULES OF PRACTICE COMMUNICATIONS § 1102.1 How addressed. All communications...

  19. 49 CFR 1102.1 - How addressed.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 8 2013-10-01 2013-10-01 false How addressed. 1102.1 Section 1102.1 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION RULES OF PRACTICE COMMUNICATIONS § 1102.1 How addressed. All communications...

  20. 49 CFR 1102.1 - How addressed.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 8 2014-10-01 2014-10-01 false How addressed. 1102.1 Section 1102.1 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION RULES OF PRACTICE COMMUNICATIONS § 1102.1 How addressed. All communications...

  1. 49 CFR 1102.1 - How addressed.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 8 2012-10-01 2012-10-01 false How addressed. 1102.1 Section 1102.1 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION RULES OF PRACTICE COMMUNICATIONS § 1102.1 How addressed. All communications...

  2. 49 CFR 1102.1 - How addressed.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 8 2011-10-01 2011-10-01 false How addressed. 1102.1 Section 1102.1 Transportation Other Regulations Relating to Transportation (Continued) SURFACE TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION RULES OF PRACTICE COMMUNICATIONS § 1102.1 How addressed. All communications...

  3. Public Address Systems. Specifications - Installation - Operation.

    ERIC Educational Resources Information Center

    Palmer, Fred M.

    Provisions for public address in new construction of campus buildings (specifications, installations, and operation of public address systems), are discussed in non-technical terms. Consideration is given to microphones, amplifiers, loudspeakers and the placement and operation of various different combinations. (FS)

  4. 49 CFR 369.6 - Address.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS REPORTS OF MOTOR CARRIERS § 369.6 Address. The following address must be used by motor carriers when submitting a report, requesting an exemption from filing...

  5. 16 CFR 0.2 - Official address.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Official address. 0.2 Section 0.2 Commercial Practices FEDERAL TRADE COMMISSION ORGANIZATION, PROCEDURES AND RULES OF PRACTICE ORGANIZATION § 0.2... 20580, unless otherwise specifically directed. The Commission's Web site address is www.ftc.gov....

  6. Approaches for Resolving Dynamic IP Addressing.

    ERIC Educational Resources Information Center

    Foo, Schubert; Hui, Siu Cheung; Yip, See Wai; He, Yulan

    1997-01-01

    A problem with dynamic Internet protocol (IP) addressing arises when the Internet connection is through an Internet provider since the IP address is allocated only at connection time. This article examines a number of online and offline methods for resolving the problem. Suggests dynamic domain name system (DNS) and directory service look-up are…

  7. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Correspondence addresses. 41....10 Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in... all other correspondence in an application or a patent involved in an appeal to the Board for which...

  8. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Correspondence addresses. 41....10 Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in... all other correspondence in an application or a patent involved in an appeal to the Board for which...

  9. 37 CFR 41.10 - Correspondence addresses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Correspondence addresses. 41....10 Correspondence addresses. Except as the Board may otherwise direct, (a) Appeals. Correspondence in... all other correspondence in an application or a patent involved in an appeal to the Board for which...

  10. History Forum Addresses Creation/Evolution Controversy.

    ERIC Educational Resources Information Center

    Schweinsberg, John

    1997-01-01

    A series of programs entitled Creationism and Evolution: The History of a Controversy was presented at the University of Alabama in Huntsville. The controversy was addressed from an historical and sociological, rather than a scientific perspective. Speakers addressed the evolution of scientific creationism, ancient texts versus sedimentary rocks…

  11. 34 CFR 674.44 - Address searches.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Address searches. 674.44 Section 674.44 Education..., DEPARTMENT OF EDUCATION FEDERAL PERKINS LOAN PROGRAM Due Diligence § 674.44 Address searches. (a) If mail... litigation; (2) The account is assigned to the United States; or (3) The account is written off under §...

  12. 34 CFR 674.44 - Address searches.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 3 2011-07-01 2011-07-01 false Address searches. 674.44 Section 674.44 Education..., DEPARTMENT OF EDUCATION FEDERAL PERKINS LOAN PROGRAM Due Diligence § 674.44 Address searches. (a) If mail... litigation; (2) The account is assigned to the United States; or (3) The account is written off under §...

  13. Forms of Address in Chilean Spanish

    ERIC Educational Resources Information Center

    Bishop, Kelley; Michnowicz, Jim

    2010-01-01

    The present investigation examines possible social and linguistic factors that influence forms of address used in Chilean Spanish with various interlocutors. A characteristic of the Spanish of Chile is the use of a variety of forms of address for the second person singular, "tu", "vos", and "usted", with corresponding…

  14. Image compression using address-vector quantization

    NASA Astrophysics Data System (ADS)

    Nasrabadi, Nasser M.; Feng, Yushu

    1990-12-01

    A novel vector quantization scheme, the address-vector quantizer (A-VQ), is proposed which exploits the interblock correlation by encoding a group of blocks together using an address-codebook (AC). The AC is a set of address-codevectors (ACVs), each representing a combination of addresses or indices. Each element of the ACV is an address of an entry in the LBG-codebook, representing a vector-quantized block. The AC consists of an active (addressable) region and an inactive (nonaddressable) region. During encoding the ACVs in the AC are reordered adaptively to bring the most probable ACVs into the active region. When encoding an ACV, the active region is checked, and if such an address combination exists, its index is transmitted to the receiver. Otherwise, the address of each block is transmitted individually. The SNR of the images encoded by the A-VQ method is the same as that of a memoryless vector quantizer, but the bit rate is by a factor of approximately two.

  15. Automated measurement of printer effective addressability

    NASA Astrophysics Data System (ADS)

    Cooper, Brian E.; Eid, Ahmed H.; Rippetoe, Edward E.

    2014-01-01

    When evaluating printer resolution, addressability is a key consideration. Addressability defines the maximum number of spots or samples within a given distance, independent of the size of the spots when printed. Effective addressability is the addressability demonstrated by the final, printed output. It is the minimum displacement possible between the centers of printed objects. In this paper, we present a measurement procedure for effective addressability that offers an automated way to experimentally determine the addressability of the printed output. It requires printing, scanning, and measuring a test target. The effective addressability test target contains two types of elements, repeated to fill the page: fiducial lines and line segments. The fiducial lines serve as a relative reference for the incremental displacements of the individual line segments, providing a way to tolerate larger-scale physical distortions in the printer. An ordinary reflection scanner captures the printed test target. By rotating the page on the scanner, it is possible to measure effective addressability well beyond the scanner's sampling resolution. The measurement algorithm computes the distribution of incremental displacements, forming either a unimodal or bimodal histogram. In the latter case, the mean of the second (non-zero) peak indicates the effective addressability. In the former case, the printer successfully rendered the target's resolution, requiring another iteration of the procedure after increasing the resolution of the test target. The algorithm automatically estimates whether the histogram is unimodal or bimodal and computes parameters describing the quality of the measured histogram. Several experiments have refined the test target and measurement procedure, including two round-robin evaluations by the ISO WG4 committee. Results include an analysis of approximately 150 printed samples. The effective addressability attribute and measurement procedure are included in

  16. Best Practices & Outstanding Initiatives

    ERIC Educational Resources Information Center

    Training, 2012

    2012-01-01

    In this article, "Training" editors recognize innovative and successful learning and development programs and practices submitted in the 2012 Training Top 125 application. Best practices: (1) Edward Jones: Practice Makes Perfect (sales training); (2) Grant Thornton LLP: Senior Manager Development Program (SMDP); (3) MetLife, Inc.: Top Advisor…

  17. Outstanding student papers

    NASA Astrophysics Data System (ADS)

    Olle Norberg was honored for his presentation of “The Astrid Microsatellite Mission—An Attempt at Energetic Neutral Atom Imaging.” Norberg received a M.Sc. (1988) in engineering physics from the Royal Institute of Technology, Stockholm. He is currently pursuing a Ph.D. in space plasma physics at the Swedish Institute of Space Physics, Kiruna, Sweden, where he is a research assistant. His research interests include the study of magnetospheric plasmas, and space plasma instrumentation. He has been studying the hot plasma data from the Phobos-2 Mars mission and the Freja mission. Norberg was a principal investigator on the Swedish Astrid-1 mission, launched in January 1995 to study neutral atoms generated in the ring current.

  18. Outstanding reviewers 2014

    NASA Astrophysics Data System (ADS)

    2015-09-01

    Every article published in this Journal goes through a rigorous review process. The reviewers are experts in their field, and undertake this service voluntarily with advancement of their fields as the only motivation. We acknowledge our debt to the reviewers for this service and in an earlier issue (Quaternary Science Reviews, Volume 107, Pages 276-280, http://dx.doi.org/10.1016/S0277-3791(14)00458-2)

  19. Nonlinear plasmonic imaging techniques and their biological applications

    NASA Astrophysics Data System (ADS)

    Deka, Gitanjal; Sun, Chi-Kuang; Fujita, Katsumasa; Chu, Shi-Wei

    2017-01-01

    Nonlinear optics, when combined with microscopy, is known to provide advantages including novel contrast, deep tissue observation, and minimal invasiveness. In addition, special nonlinearities, such as switch on/off and saturation, can enhance the spatial resolution below the diffraction limit, revolutionizing the field of optical microscopy. These nonlinear imaging techniques are extremely useful for biological studies on various scales from molecules to cells to tissues. Nevertheless, in most cases, nonlinear optical interaction requires strong illumination, typically at least gigawatts per square centimeter intensity. Such strong illumination can cause significant phototoxicity or even photodamage to fragile biological samples. Therefore, it is highly desirable to find mechanisms that allow the reduction of illumination intensity. Surface plasmon, which is the collective oscillation of electrons in metal under light excitation, is capable of significantly enhancing the local field around the metal nanostructures and thus boosting up the efficiency of nonlinear optical interactions of the surrounding materials or of the metal itself. In this mini-review, we discuss the recent progress of plasmonics in nonlinear optical microscopy with a special focus on biological applications. The advancement of nonlinear imaging modalities (including incoherent/coherent Raman scattering, two/three-photon luminescence, and second/third harmonic generations that have been amalgamated with plasmonics), as well as the novel subdiffraction limit imaging techniques based on nonlinear behaviors of plasmonic scattering, is addressed.

  20. Nonlinear plasmonic imaging techniques and their biological applications

    NASA Astrophysics Data System (ADS)

    Deka, Gitanjal; Sun, Chi-Kuang; Fujita, Katsumasa; Chu, Shi-Wei

    2016-07-01

    Nonlinear optics, when combined with microscopy, is known to provide advantages including novel contrast, deep tissue observation, and minimal invasiveness. In addition, special nonlinearities, such as switch on/off and saturation, can enhance the spatial resolution below the diffraction limit, revolutionizing the field of optical microscopy. These nonlinear imaging techniques are extremely useful for biological studies on various scales from molecules to cells to tissues. Nevertheless, in most cases, nonlinear optical interaction requires strong illumination, typically at least gigawatts per square centimeter intensity. Such strong illumination can cause significant phototoxicity or even photodamage to fragile biological samples. Therefore, it is highly desirable to find mechanisms that allow the reduction of illumination intensity. Surface plasmon, which is the collective oscillation of electrons in metal under light excitation, is capable of significantly enhancing the local field around the metal nanostructures and thus boosting up the efficiency of nonlinear optical interactions of the surrounding materials or of the metal itself. In this mini-review, we discuss the recent progress of plasmonics in nonlinear optical microscopy with a special focus on biological applications. The advancement of nonlinear imaging modalities (including incoherent/coherent Raman scattering, two/three-photon luminescence, and second/third harmonic generations that have been amalgamated with plasmonics), as well as the novel subdiffraction limit imaging techniques based on nonlinear behaviors of plasmonic scattering, is addressed.

  1. Nonlinear physics of shear Alfvén waves

    SciTech Connect

    Zonca, Fulvio; Chen, Liu

    2014-02-12

    Shear Alfvén waves (SAW) play fundamental roles in thermonuclear plasmas of fusion interest, since they are readily excited by energetic particles in the MeV range as well as by the thermal plasma components. Thus, understanding fluctuation induced transport in burning plasmas requires understanding nonlinear SAW physics. There exist two possible routes to nonlinear SAW physics: (i) wave-wave interactions and the resultant spectral energy transfer; (ii) nonlinear wave-particle interactions of SAW instabilities with energetic particles. Within the first route, it is advantageous to understand and describe nonlinear processes in term of proximity of the system to the Alfvénic state, where wave-wave interactions are minimized due to the cancellation of Reynolds and Maxwell stresses. Here, various wave-wave nonlinear dynamics are elucidated in terms of how they break the Alfvénic state. In particular, we discuss the qualitative and quantitative modification of the SAW parametric decay process due to finite ion compressibility and finite ion Larmor radius. We also show that toroidal geometry plays a crucial role in the nonlinear excitation of zonal structures by Alfvén eigenmodes. Within the second route, the coherent nonlinear dynamics of structures in the energetic particle phase space, by which secular resonant particle transport can occur on meso- and macro-scales, must be addressed and understood. These 'nonlinear equilibria' or 'phase-space zonal structures' dynamically evolve on characteristic (fluctuation induced) turbulent transport time scales, which are generally of the same order of the nonlinear time scale of the underlying fluctuations. In this work, we introduce the general structure of nonlinear Schrödinger equations with complex integro-differential nonlinear terms, which govern these physical processes. To elucidate all these aspects, theoretical analyses are presented together with numerical simulation results.

  2. Algebraic Nonlinear Collective Motion

    NASA Astrophysics Data System (ADS)

    Troupe, J.; Rosensteel, G.

    1998-11-01

    Finite-dimensional Lie algebras of vector fields determine geometrical collective models in quantum and classical physics. Every set of vector fields on Euclidean space that generates the Lie algebra sl(3, R) and contains the angular momentum algebra so(3) is determined. The subset of divergence-free sl(3, R) vector fields is proven to be indexed by a real numberΛ. TheΛ=0 solution is the linear representation that corresponds to the Riemann ellipsoidal model. The nonlinear group action on Euclidean space transforms a certain family of deformed droplets among themselves. For positiveΛ, the droplets have a neck that becomes more pronounced asΛincreases; for negativeΛ, the droplets contain a spherical bubble of radius |Λ|1/3. The nonlinear vector field algebra is extended to the nonlinear general collective motion algebra gcm(3) which includes the inertia tensor. The quantum algebraic models of nonlinear nuclear collective motion are given by irreducible unitary representations of the nonlinear gcm(3) Lie algebra. These representations model fissioning isotopes (Λ>0) and bubble and two-fluid nuclei (Λ<0).

  3. Beads-on-String Structured Nanofibers for Smart and Reversible Oil/Water Separation with Outstanding Antifouling Property.

    PubMed

    Wang, Yuanfeng; Lai, Chuilin; Wang, Xiaowen; Liu, Yang; Hu, Huawen; Guo, Yujuan; Ma, Kaikai; Fei, Bin; Xin, John H

    2016-09-28

    It is challenging to explore a unified solution for the treatment of oily wastewater from complex sources. Thus, membrane materials with flexible separation schemes are highly desired. Herein, we fabricated a smart membrane by electrospinning TiO2 doped polyvinylidene fluoride (PVDF) nanofibers. The as-formed beads-on-string structure and hierarchical roughness of the nanofibers contribute to its superwetting/resisting property to liquids, which is desirable in oil/water separation. Switched simply by UV (or sunlight) irradiation and heating treatment, the smart membrane can realize reversible separation of oil/water mixtures by selectively allowing water or oil to pass through alone. Most importantly, the as-prepared nanofiber membrane possesses outstanding antifouling and self-cleaning performance resulting from the photocatalytic property of TiO2, which has practical significance in saving solvents and recycling materials. This work provides a route for fabricating cost-effective, easily scaled up, and recyclable membranes for on-demand oil/water separation in versatile situations, which can be of great usage in the new green separation technology.

  4. Polymer Nanodot-Hybridized Alkyl Silicon Oxide Nanostructures for Organic Memory Transistors with Outstanding High-Temperature Operation Stability

    PubMed Central

    Lee, Chulyeon; Seo, Jooyeok; Kim, Jeongnam; Jeong, Jaehoon; Han, Hyemi; Kim, Hwajeong; Kim, Youngkyoo

    2016-01-01

    Organic memory devices (OMDs) are becoming more important as a core component in flexible electronics era because of their huge potentials for ultrathin, lightweight and flexible plastic memory modules. In particular, transistor-type OMDs (TOMDs) have been gradually spotlighted due to their structural advantages possessing both memory and driving functions in single devices. Although a variety of TOMDs have been developed by introducing various materials, less attention has been paid to the stable operation at high temperatures. Here we demonstrate that the polymer nanodot-embedded alkyl silicon oxide (ASiO) hybrid materials, which are prepared by sol-gel and thermal cross-linking reactions between poly(4-vinylphenol) (PVP) and vinyltriethoxysilane, can deliver low-voltage (1~5 V) TOMDs with outstanding operation stability (>4700 cycles) at high temperatures (150 °C). The efficient low-voltage memory function is enabled by the embedded PVP nanodots with particular lattice nanostructures, while the high thermal stability is achieved by the cross-linked ASiO network structures. PMID:27703187

  5. Outstanding field emission properties of wet-processed titanium dioxide coated carbon nanotube based field emission devices

    SciTech Connect

    Xu, Jinzhuo; Ou-Yang, Wei Chen, Xiaohong; Guo, Pingsheng; Piao, Xianqing; Sun, Zhuo; Xu, Peng; Wang, Miao; Li, Jun

    2015-02-16

    Field emission devices using a wet-processed composite cathode of carbon nanotube films coated with titanium dioxide exhibit outstanding field emission characteristics, including ultralow turn on field of 0.383 V μm{sup −1} and threshold field of 0.657 V μm{sup −1} corresponding with a very high field enhancement factor of 20 000, exceptional current stability, and excellent emission uniformity. The improved field emission properties are attributed to the enhanced edge effect simultaneously with the reduced screening effect, and the lowered work function of the composite cathode. In addition, the highly stable electron emission is found due to the presence of titanium dioxide nanoparticles on the carbon nanotubes, which prohibits the cathode from the influence of ions and free radical created in the emission process as well as residual oxygen gas in the device. The high-performance solution-processed composite cathode demonstrates great potential application in vacuum electronic devices.

  6. Polymer Nanodot-Hybridized Alkyl Silicon Oxide Nanostructures for Organic Memory Transistors with Outstanding High-Temperature Operation Stability

    NASA Astrophysics Data System (ADS)

    Lee, Chulyeon; Seo, Jooyeok; Kim, Jeongnam; Jeong, Jaehoon; Han, Hyemi; Kim, Hwajeong; Kim, Youngkyoo

    2016-10-01

    Organic memory devices (OMDs) are becoming more important as a core component in flexible electronics era because of their huge potentials for ultrathin, lightweight and flexible plastic memory modules. In particular, transistor-type OMDs (TOMDs) have been gradually spotlighted due to their structural advantages possessing both memory and driving functions in single devices. Although a variety of TOMDs have been developed by introducing various materials, less attention has been paid to the stable operation at high temperatures. Here we demonstrate that the polymer nanodot-embedded alkyl silicon oxide (ASiO) hybrid materials, which are prepared by sol-gel and thermal cross-linking reactions between poly(4-vinylphenol) (PVP) and vinyltriethoxysilane, can deliver low-voltage (1~5 V) TOMDs with outstanding operation stability (>4700 cycles) at high temperatures (150 °C). The efficient low-voltage memory function is enabled by the embedded PVP nanodots with particular lattice nanostructures, while the high thermal stability is achieved by the cross-linked ASiO network structures.

  7. Polymer Nanodot-Hybridized Alkyl Silicon Oxide Nanostructures for Organic Memory Transistors with Outstanding High-Temperature Operation Stability.

    PubMed

    Lee, Chulyeon; Seo, Jooyeok; Kim, Jeongnam; Jeong, Jaehoon; Han, Hyemi; Kim, Hwajeong; Kim, Youngkyoo

    2016-10-05

    Organic memory devices (OMDs) are becoming more important as a core component in flexible electronics era because of their huge potentials for ultrathin, lightweight and flexible plastic memory modules. In particular, transistor-type OMDs (TOMDs) have been gradually spotlighted due to their structural advantages possessing both memory and driving functions in single devices. Although a variety of TOMDs have been developed by introducing various materials, less attention has been paid to the stable operation at high temperatures. Here we demonstrate that the polymer nanodot-embedded alkyl silicon oxide (ASiO) hybrid materials, which are prepared by sol-gel and thermal cross-linking reactions between poly(4-vinylphenol) (PVP) and vinyltriethoxysilane, can deliver low-voltage (1~5 V) TOMDs with outstanding operation stability (>4700 cycles) at high temperatures (150 °C). The efficient low-voltage memory function is enabled by the embedded PVP nanodots with particular lattice nanostructures, while the high thermal stability is achieved by the cross-linked ASiO network structures.

  8. Large-scale production of graphitic carbon nitride with outstanding nitrogen photofixation ability via a convenient microwave treatment

    NASA Astrophysics Data System (ADS)

    Ma, Huiqiang; Shi, Zhenyu; Li, Shuang; Liu, Na

    2016-08-01

    A convenient microwave treatment for synthesizing graphitic carbon nitride (g-C3N4) with outstanding nitrogen photofixation ability under visible light is reported. X-ray diffraction (XRD), N2 adsorption, UV-vis spectroscopy, SEM, N2-TPD, EPR, photoluminescence (PL) and photocurrent measurements were used to characterize the prepared catalysts. The results indicate that microwave treatment can form many irregular pores in as-prepared g-C3N4, which causes the increased surface area and separation rate of electrons and holes. More importantly, microwave treatment causes the formation of many nitrogen vacancies in as-prepared g-C3N4. These nitrogen vacancies not only serve as active sites to adsorb and activate N2 molecules but also promote interfacial charge transfer from catalysts to N2 molecules, thus significantly improving the nitrogen photofixation ability. Moreover, the present process is a convenient method for large-scale production of g-C3N4 which is significantly important for the practical application.

  9. Addressing Your Child's Weight at the Doctor

    MedlinePlus

    ... a Healthy Heart Healthy Kids Our Kids Programs Childhood Obesity What is childhood obesity? Overweight in Children BMI in Children Is Childhood Obesity an Issue in Your Home? Addressing your Child's ...

  10. 7 CFR 504.5 - Address.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... USER FEES § 504.5 Address. Deposits of and requests for microbial patent cultures should be directed to the Curator, ARS Patent Culture Collection, Northern Regional Research Center, USDA-ARS, 1815...

  11. 7 CFR 504.5 - Address.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... USER FEES § 504.5 Address. Deposits of and requests for microbial patent cultures should be directed to the Curator, ARS Patent Culture Collection, Northern Regional Research Center, USDA-ARS, 1815...

  12. 7 CFR 504.5 - Address.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... USER FEES § 504.5 Address. Deposits of and requests for microbial patent cultures should be directed to the Curator, ARS Patent Culture Collection, Northern Regional Research Center, USDA-ARS, 1815...

  13. 7 CFR 504.5 - Address.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... USER FEES § 504.5 Address. Deposits of and requests for microbial patent cultures should be directed to the Curator, ARS Patent Culture Collection, Northern Regional Research Center, USDA-ARS, 1815...

  14. 7 CFR 504.5 - Address.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... USER FEES § 504.5 Address. Deposits of and requests for microbial patent cultures should be directed to the Curator, ARS Patent Culture Collection, Northern Regional Research Center, USDA-ARS, 1815...

  15. 76 FR 27020 - Representative and Address Provisions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE United States Patent and Trademark Office Representative and Address Provisions ACTION: Proposed collection; comment request. SUMMARY: The United States Patent and Trademark Office (USPTO), as part of...

  16. Optical Addressing And Clocking Of RAM's

    NASA Technical Reports Server (NTRS)

    Johnston, Alan R.; Nixon, Robert H.; Bergman, Larry A.; Esener, Sadik

    1989-01-01

    Proposed random-access-memory (RAM) addressing system, in which memory linked optically to read/write logic circuits, greatly increases computer operating speed. System - comprises addressing circuits including numerous lasers as signal sources, numerous optical gates including optical detectors associated with memory cells, and holographic element to direct light signals to desired memory-cell locations - applied to high-capacity digital systems, supercomputers, and complex microcircuits.

  17. Nonlinear Waves in Waveguides

    NASA Astrophysics Data System (ADS)

    Leble, Sergei B.

    S.B. Leble's book deals with nonlinear waves and their propagation in metallic and dielectric waveguides and media with stratification. The underlying nonlinear evolution equations (NEEs) are derived giving also their solutions for specific situations. The reader will find new elements to the traditional approach. Various dispersion and relaxation laws for different guides are considered as well as the explicit form of projection operators, NEEs, quasi-solitons and of Darboux transforms. Special points relate to: 1. the development of a universal asymptotic method of deriving NEEs for guide propagation; 2. applications to the cases of stratified liquids, gases, solids and plasmas with various nonlinearities and dispersion laws; 3. connections between the basic problem and soliton- like solutions of the corresponding NEEs; 4. discussion of details of simple solutions in higher- order nonsingular perturbation theory.

  18. Nonlinear optomechanics with graphene

    NASA Astrophysics Data System (ADS)

    Shaffer, Airlia; Patil, Yogesh Sharad; Cheung, Hil F. H.; Wang, Ke; Vengalattore, Mukund

    2016-05-01

    To date, studies of cavity optomechanics have been limited to exploiting the linear interactions between the light and mechanics. However, investigations of quantum signal transduction, quantum enhanced metrology and manybody physics with optomechanics each require strong, nonlinear interactions. Graphene nanomembranes are an exciting prospect for realizing such studies due to their inherently nonlinear nature and low mass. We fabricate large graphene nanomembranes and study their mechanical and optical properties. By using dark ground imaging techniques, we correlate their eigenmode shapes with the measured dissipation. We study their hysteretic response present even at low driving amplitudes, and their nonlinear dissipation. Finally, we discuss ongoing efforts to use these resonators for studies of quantum optomechanics and force sensing. This work is supported by the DARPA QuASAR program through a Grant from the ARO.

  19. Nonlinear optical Galton board

    SciTech Connect

    Navarrete-Benlloch, C.; Perez, A.; Roldan, Eugenio

    2007-06-15

    We generalize the concept of optical Galton board (OGB), first proposed by Bouwmeester et al. [Phys. Rev. A 61, 013410 (2000)], by introducing the possibility of nonlinear self-phase modulation on the wave function during the walker evolution. If the original Galton board illustrates classical diffusion, the OGB, which can be understood as a grid of Landau-Zener crossings, illustrates the influence of interference on diffusion, and is closely connected with the quantum walk. Our nonlinear generalization of the OGB shows new phenomena, the most striking of which is the formation of nondispersive pulses in the field distribution (solitonlike structures). These exhibit a variety of dynamical behaviors, including ballistic motion, dynamical localization, nonelastic collisions, and chaotic behavior, in the sense that the dynamics is very sensitive to the nonlinearity strength.

  20. Robust H∞ filtering for discrete nonlinear delayed stochastic systems with missing measurements and randomly occurring nonlinearities

    NASA Astrophysics Data System (ADS)

    Liu, Yurong; Alsaadi, Fuad E.; Yin, Xiaozhou; Wang, Yamin

    2015-02-01

    In this paper, we are concerned with the robust H∞ filtering problem for a class of nonlinear discrete time-delay stochastic systems. The system under consideration involves parameter uncertainties, stochastic disturbances, time-varying delays and sector nonlinearities. Both missing measurements and randomly occurring nonlinearities are described via the binary switching sequences satisfying a conditional probability distribution, and the nonlinearities are assumed to be sector bounded. The problem addressed is the design of a full-order filter such that, for all admissible uncertainties, nonlinearities and time-delays, the dynamics of the filtering error is constrained to be robustly exponentially stable in the mean square, and a prescribed ? disturbance rejection attenuation level is also guaranteed. By using the Lyapunov stability theory and some new techniques, sufficient conditions are first established to ensure the existence of the desired filtering parameters. Then, the explicit expression of the desired filter gains is described in terms of the solution to a linear matrix inequality. Finally, a numerical example is exploited to show the usefulness of the results derived.

  1. Contextual analysis of machine-printed addresses

    NASA Astrophysics Data System (ADS)

    Cullen, Peter B.; Ho, Tin K.; Hull, Jonathan J.; Prussak, Michal; Srihari, Sargur N.

    1992-08-01

    The assignment of a nine digit ZIP Code (ZIP + 4 Code) to the digital image of a machine printed address block is a problem of central importance in automated mail sorting. This problem is especially difficult since most addresses do not contain ZIP + 4 Codes and often the information that must be read to match an address to one of the 28 million entries in the ZIP + 4 file is either erroneous, incomplete, or missing altogether. This paper discusses a system for interpreting a machine printed address and assigning a ZIP + 4 Code that uses a constraint satisfaction approach. Words in an address block are first segmented and parsed to assign probable semantic categories. Word images are then recognized by a combination of digit, character, and word recognition algorithms. The control structure uses a constraint satisfaction problem solving approach to match the recognition results to an entry in the ZIP + 4 file. It is shown how this technique can both determine correct responses as well as compensate for incomplete or erroneous information. Experimental results demonstrate the success of this system. In a recent test on over 1000 machine printed address blocks, the ZIP + 4 encode rate was over 73 percent. This compares to the success rate of current postal OCRs which is about 45 percent. Additionally, the word recognition algorithm recognizes over 92 percent of the input images (over 98 percent in the top 10 choices.

  2. Enhanced nonlinear optical characteristics of copper-ion-doped double crossover DNAs

    NASA Astrophysics Data System (ADS)

    Park, Byeongho; Lee, Byung Jic; Dugasani, Sreekantha Reddy; Cho, Youngho; Kim, Chulki; Seo, Minah; Lee, Taikjin; Jhon, Young Min; Choi, Jaebin; Lee, Seok; Park, Sung Ha; Jun, Seong Chan; Yeom, Dong-Il; Rotermund, Fabian; Kim, Jae Hun

    2015-10-01

    The modification of deoxyribonucleic acid (DNA) samples by sequencing the order of bases and doping copper ions opens the possibility for the design of novel nanomaterials exhibiting large optical nonlinearity. We investigated the nonlinear characteristics of copper-ion doped double crossover DNA samples for the first time to the best of our knowledge by using Z-scan and four-wave mixing methods. To accelerate the nonlinear characteristics, we prepared two types of unique DNA nanostructures composed of 148 base pairs doped with copper ions with a facile annealing method. The outstanding third-order nonlinear optical susceptibility of the copper-ion-doped DNA solution, 1.19 × 10-12 esu, was estimated by the conventional Z-scan measurement, whereas the four-wave mixing experiment was also investigated. In the visible spectral range, the copper-ion-doped DNA solution samples provided competent four-wave mixing signals with a remarkable conversion efficiency of -4.15 dB for the converted signal at 627 nm. The interactions between DNA and copper ions contribute to the enhancement of nonlinearity due to structural and functional changes. The present study signifies that the copper-ion-doped double crossover DNA is a potential candidate as a highly efficient novel material for further nonlinear optical applications.

  3. Linear Feedback Stabilization of Nonlinear Systems with an Uncontrollable Critical Mode

    DTIC Science & Technology

    1992-11-17

    mode that is uncontrollable. The results complement previous work on the synthesis of nonlinear stabilizing control laws. The present work addresses...analysis and stabilizing control design employ results on stability of bifurcations of parametrized systems.

  4. It's Not Just about Value for Money: A Case Study of Values-Led Implementation of the Pupil Premium in Outstanding Schools

    ERIC Educational Resources Information Center

    Abbott, Ian; Middlewood, David; Robinson, Sue

    2015-01-01

    This article draws on data collected from a series of semi-structured interviews with headteachers and other stakeholders on the use of the Pupil Premium in Ofsted-rated outstanding schools. It has a focus on the significance of fundamental principles in determining how effective use is made of additional resources. In particular, the importance…

  5. Behind Each Outstanding Teacher: An Analysis of the Teacher Tribute Award Nominations for the Student Loan Marketing Association, 1988-89.

    ERIC Educational Resources Information Center

    Saxe, Richard W.

    Research assesses the attitudinal factors that characterize outstanding first-year elementary and secondary school teachers as nominated by their superintendents and judged for the Student Loan Marketing Association (Sallie Mae) by a panel of experts selected by the American Association of School Administrators. Sallie Mae nomination forms…

  6. Nonlinear magnetohydrodynamic stability

    NASA Technical Reports Server (NTRS)

    Bauer, F.; Betancourt, O.; Garabedian, P.

    1981-01-01

    The computer code developed by Bauer et al. (1978) for the study of the magnetohydrodynamic equilibrium and stability of a plasma in toroidal geometry is extended so that the growth rates of instabilities may be estimated more accurately. The original code, which is based on the variational principle of ideal magnetohydrodynamics, is upgraded by the introduction of a nonlinear formula for the growth rate of an unstable mode which acts as a quantitative measure of instability that is important in estimating numerical errors. The revised code has been applied to the determination of the nonlinear saturation, ballooning modes and beta limits for tokamaks, stellarators and torsatrons.

  7. Nonlinear Fault Diagnosis,

    DTIC Science & Technology

    1981-05-01

    Systems, New York, Marcel Dekker, (to appear). 3. Desoer , C.A. and S.E. Kuh, Basic Circuit Theory, McGraw-Hill, New York, 1969, pp. 423-425. 130 NONLINEAR...DIAGNOSIS A 7*ssior For 1 MU3 CRA&T IY’IC TAB Ju-st i.cat IC- P.U A: CONTENTS Fault Diagnosis in Electronic Circuits , R. Saeks and R.-w. Liu...Vincentelli and R. Saeks .............. 61 Multitest Diagnosibility of Nonlinear Circuits and Systems, A. Sangiovanni-Vincentelli and R. Saeks

  8. Nonlinear Wave Propagation

    DTIC Science & Technology

    2015-05-07

    honeycomb lattices, M.J. Ablowitz and Y. Zhu, SIAM J. Appl. Math. 87 (2013) 19591979 11. Nonlinear Temporal-Spatial Surface Plasmon Polaritons , M. J. Ablowitz...temporal-spatial surface plasmon polaritons . Op- tics Communications, 330:49–55, 2014. 37 [39] M.C. Rechtsman, Y. Plotnik, J.M. Zeuner, , D. Song, Z...honeycomb lattices, M.J. Ablowitz and Y. Zhu, SIAM J. Appl. Math., Vol. 87 (2013) 1959-1979 11. Nonlinear Temporal-Spatial Surface Plasmon Polaritons

  9. Problems of nonlinear deformation

    NASA Astrophysics Data System (ADS)

    Grigoliuk, E. I.; Shalashilin, V. I.

    A method of continuing the solution is discussed with respect to a parameter for a certain class of nonlinear problems in solid mechanics. Modifications of the method are developed in order to implement a unified continuation process at regular and limit points in the set of solutions, with extensions to nonlinear boundary value problems. Algorithms are developed for solving large deflection problems of elastic arches and large axisymmetric deflection problems for shells of revolution. In particular, the algorithms are used for the analysis of large deflections of circular arches and toroidal shells. Examples of natural vibration and stability problems for parallelograms and trapezoidal membranes and panels are given.

  10. Solitons in nonlinear optics

    SciTech Connect

    Maimistov, Andrei I

    2010-11-13

    The classic examples of optical phenomena resulting in the appearance of solitons are self-focusing, self-induced transparency, and parametric three-wave interaction. To date, the list of the fields of nonlinear optics and models where solitons play an important role has significantly expanded. Now long-lived or stable solitary waves are called solitons, including, for example, dissipative, gap, parametric, and topological solitons. This review considers nonlinear optics models giving rise to the appearance of solitons in a narrow sense: solitary waves corresponding to the solutions of completely integrable systems of equations basic for the models being discussed. (review)

  11. Nonlinear aerodynamic wing design

    NASA Technical Reports Server (NTRS)

    Bonner, Ellwood

    1985-01-01

    The applicability of new nonlinear theoretical techniques is demonstrated for supersonic wing design. The new technology was utilized to define outboard panels for an existing advanced tactical fighter model. Mach 1.6 maneuver point design and multi-operating point compromise surfaces were developed and tested. High aerodynamic efficiency was achieved at the design conditions. A corollary result was that only modest supersonic penalties were incurred to meet multiple aerodynamic requirements. The nonlinear potential analysis of a practical configuration arrangement correlated well with experimental data.

  12. Nonlinear interferometric vibrational imaging.

    PubMed

    Marks, Daniel L; Boppart, Stephen A

    2004-03-26

    Coherent anti-Stokes Raman scattering (CARS) processes are "coherent," but the phase of the anti-Stokes radiation is lost by most incoherent spectroscopic CARS measurements. We propose a Raman microscopy imaging method called nonlinear interferometric vibrational imaging, which measures Raman spectra by obtaining the temporal anti-Stokes signal through nonlinear interferometry. With a more complete knowledge of the anti-Stokes signal, we show through simulations that a high-resolution Raman spectrum can be obtained of a molecule in a single pulse using broad band radiation. This could be useful for identifying the three-dimensional spatial distribution of molecular species in tissue.

  13. Perturbed nonlinear differential equations

    NASA Technical Reports Server (NTRS)

    Proctor, T. G.

    1972-01-01

    The existence of a solution defined for all t and possessing a type of boundedness property is established for the perturbed nonlinear system y = f(t,y) + F(t,y). The unperturbed system x = f(t,x) has a dichotomy in which some solutions exist and are well behaved as t increases to infinity, and some solution exists and are well behaved as t decreases to minus infinity. A similar study is made for a perturbed nonlinear differential equation defined on a half line, R+, and the existence of a family of solutions with special boundedness properties is established. The ideas are applied to integral manifolds.

  14. Addressing Facility Needs for Concrete Assessment Using Ultrasonic Testing: Mid-year Report

    SciTech Connect

    Ulrich, Timothy J. II; Payan, Cedric; Roberts, Peter M.

    2012-03-28

    The UFD Gap Analysis to Support Extended Storage of Used Nuclear Fuel (June 30, 2011) emphasizes the need for the development of monitoring techniques and technologies for dry storage cask materials. A high priority is given to the development of 'systems for early detection of confinement boundary degradation.' This requires both new techniques for monitoring and inspection, as well as new measurable parameters to quantify mechanical degradation. The use of Nonlinear Elastic Wave Spectroscopy (NEWS) has been shown to provide sensitive parameters correlating to mechanical degradation in a wide variety of materials. Herein we report upon recent research performed to address the high priority of concrete degradation using a selection of these techniques and compare to a ASTM standard ultrasonic technique. Also reported are the near term plans to continue this research in the remaining FY and into the coming years. This research was conducted at Los Alamos National Laboratory (LANL) in the Acoustics Lab of the Geophysics group in the Earth and Environmental Sciences division, and in collaboration with the Laboratory for Nondestructive Evaluation at the University of the Mediterranean (Aix en Provence, France) and the Electrical Power Research Institute (EPRI). The objective of this research project was to determine the feasibility of using an NDE technique based on non-linear ultrasound for determining the depth and degree of microcracking in the near surface of concrete and to assess the degree of sensitivity of such technique. This objective is reached by the means of combining linear and nonlinear measurements, associated with numerical simulation. We first study the global effect of thermal damage on concrete's linear and nonlinear properties by resonance inspection techniques. We show that standard pulse wave speed techniques are not relevant to extract mechanical properties of concrete. The high sensitivity of measured nonlinearity is shown and serves as a

  15. The Formation of the Second-Order Nonlinearity in Thermally Poled Fused Silica Glass

    DTIC Science & Technology

    2007-11-02

    NONIINEARITY IN THERMALLY POLED FUSED SILICA GLASS 6. AUTHOR(S) THOMAS GUSTAVE ALLEY 5. FUNDING NUMBERS 7. PERFORMING ORGANIZATION NAME(S) AND...ADDRESS(ES) The University of New Mexico 8. PERFORMING ORGANIZATION REPORT NUMBER 98-020D 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES...self- organized , photoinduced, second-order nonlinearity. The most widely accepted explanation attributes the nonlinearity to an asymmetric

  16. Nonlinearity as a resource for nonclassicality in anharmonic systems

    NASA Astrophysics Data System (ADS)

    Albarelli, Francesco; Ferraro, Alessandro; Paternostro, Mauro; Paris, Matteo G. A.

    2016-03-01

    Nonclassicality is a key ingredient for quantum enhanced technologies and experiments involving macroscopic quantum coherence. Considering various exactly solvable quantum-oscillator systems, we address the role played by the anharmonicity of their potential in the establishment of nonclassical features. Specifically, we show that a monotonic relation exists between the entropic nonlinearity of the considered potentials and their ground-state nonclassicality, as quantified by the negativity of the Wigner function. In addition, in order to clarify the role of squeezing, which is not captured by the negativity of the Wigner function, we focus on the Glauber-Sudarshan P function and address the nonclassicality-nonlinearity relation using the entanglement potential. Finally, we consider the case of a generic sixth-order potential confirming the idea that nonlinearity is a resource for the generation of nonclassicality and may serve as a guideline for the engineering of quantum oscillators.

  17. Generation of linear dynamic models from a digital nonlinear simulation

    NASA Technical Reports Server (NTRS)

    Daniele, C. J.; Krosel, S. M.

    1979-01-01

    The results and methodology used to derive linear models from a nonlinear simulation are presented. It is shown that averaged positive and negative perturbations in the state variables can reduce numerical errors in finite difference, partial derivative approximations and, in the control inputs, can better approximate the system response in both directions about the operating point. Both explicit and implicit formulations are addressed. Linear models are derived for the F 100 engine, and comparisons of transients are made with the nonlinear simulation. The problem of startup transients in the nonlinear simulation in making these comparisons is addressed. Also, reduction of the linear models is investigated using the modal and normal techniques. Reduced-order models of the F 100 are derived and compared with the full-state models.

  18. Multiple model self-tuning control for a class of nonlinear systems

    NASA Astrophysics Data System (ADS)

    Huang, Miao; Wang, Xin; Wang, Zhenlei

    2015-10-01

    This study develops a novel nonlinear multiple model self-tuning control method for a class of nonlinear discrete-time systems. An increment system model and a modified robust adaptive law are proposed to expand the application range, thus eliminating the assumption that either the nonlinear term of the nonlinear system or its differential term is global-bounded. The nonlinear self-tuning control method can address the situation wherein the nonlinear system is not subject to a globally uniformly asymptotically stable zero dynamics by incorporating the pole-placement scheme. A novel, nonlinear control structure based on this scheme is presented to improve control precision. Stability and convergence can be confirmed when the proposed multiple model self-tuning control method is applied. Furthermore, simulation results demonstrate the effectiveness of the proposed method.

  19. Nonlinear Perspectives on Family Process: Chaos and Catastrophe Theories.

    ERIC Educational Resources Information Center

    Ward, Margaret; Koopmans, Matthijs

    This paper explores the principal features of nonlinear dynamical systems and applies the theory to parents' acceptance of a child adopted at an older age. Although family systems theories tend to be weak in addressing family change, chaos theory and catastrophe theory allow consideration of sudden, discontinuous change. If stable, the family may…

  20. Nonlinear interaction of meta-atoms through optical coupling

    SciTech Connect

    Slobozhanyuk, A. P.; Kapitanova, P. V.; Filonov, D. S.; Belov, P. A.; Powell, D. A.; Shadrivov, I. V.; Kivshar, Yu. S.; Lapine, M.; McPhedran, R. C.

    2014-01-06

    We propose and experimentally demonstrate a multi-frequency nonlinear coupling mechanism between split-ring resonators. We engineer the coupling between two microwave resonators through optical interaction, whilst suppressing the direct electromagnetic coupling. This allows for a power-dependent interaction between the otherwise independent resonators, opening interesting opportunities to address applications in signal processing, filtering, directional coupling, and electromagnetic compatibility.

  1. Stability properties of nonlinear dynamical systems and evolutionary stable states

    NASA Astrophysics Data System (ADS)

    Gleria, Iram; Brenig, Leon; Rocha Filho, Tarcísio M.; Figueiredo, Annibal

    2017-03-01

    In this paper we address the problem of stability in a general class of non-linear systems. We establish a link between the concepts of asymptotic stable interior fixed points of square Quasi-Polynomial systems and evolutionary stable states, a property of some payoff matrices arising from evolutionary games.

  2. LTR-retrotransposons in R. exoculata and other crustaceans: the outstanding success of GalEa-like copia elements.

    PubMed

    Piednoël, Mathieu; Donnart, Tifenn; Esnault, Caroline; Graça, Paula; Higuet, Dominique; Bonnivard, Eric

    2013-01-01

    Transposable elements are major constituents of eukaryote genomes and have a great impact on genome structure and stability. They can contribute to the genetic diversity and evolution of organisms. Knowledge of their distribution among several genomes is an essential condition to study their dynamics and to better understand their role in species evolution. LTR-retrotransposons have been reported in many diverse eukaryote species, describing a ubiquitous distribution. Given their abundance, diversity and their extended ranges in C-values, environment and life styles, crustaceans are a great taxon to investigate the genomic component of adaptation and its possible relationships with TEs. However, crustaceans have been greatly underrepresented in transposable element studies. Using both degenerate PCR and in silico approaches, we have identified 35 Copia and 46 Gypsy families in 15 and 18 crustacean species, respectively. In particular, we characterized several full-length elements from the shrimp Rimicaris exoculata that is listed as a model organism from hydrothermal vents. Phylogenic analyses show that Copia and Gypsy retrotransposons likely present two opposite dynamics within crustaceans. The Gypsy elements appear relatively frequent and diverse whereas Copia are much more homogeneous, as 29 of them belong to the single GalEa clade, and species- or lineage-dependent. Our results also support the hypothesis of the Copia retrotransposon scarcity in metazoans compared to Gypsy elements. In such a context, the GalEa-like elements present an outstanding wide distribution among eukaryotes, from fishes to red algae, and can be even highly predominant within a large taxon, such as Malacostraca. Their distribution among crustaceans suggests a dynamics that follows a "domino days spreading" branching process in which successive amplifications may interact positively.

  3. LTR-Retrotransposons in R. exoculata and Other Crustaceans: The Outstanding Success of GalEa-Like Copia Elements

    PubMed Central

    Esnault, Caroline; Graça, Paula; Higuet, Dominique; Bonnivard, Eric

    2013-01-01

    Transposable elements are major constituents of eukaryote genomes and have a great impact on genome structure and stability. They can contribute to the genetic diversity and evolution of organisms. Knowledge of their distribution among several genomes is an essential condition to study their dynamics and to better understand their role in species evolution. LTR-retrotransposons have been reported in many diverse eukaryote species, describing a ubiquitous distribution. Given their abundance, diversity and their extended ranges in C-values, environment and life styles, crustaceans are a great taxon to investigate the genomic component of adaptation and its possible relationships with TEs. However, crustaceans have been greatly underrepresented in transposable element studies. Using both degenerate PCR and in silico approaches, we have identified 35 Copia and 46 Gypsy families in 15 and 18 crustacean species, respectively. In particular, we characterized several full-length elements from the shrimp Rimicaris exoculata that is listed as a model organism from hydrothermal vents. Phylogenic analyses show that Copia and Gypsy retrotransposons likely present two opposite dynamics within crustaceans. The Gypsy elements appear relatively frequent and diverse whereas Copia are much more homogeneous, as 29 of them belong to the single GalEa clade, and species- or lineage-dependent. Our results also support the hypothesis of the Copia retrotransposon scarcity in metazoans compared to Gypsy elements. In such a context, the GalEa-like elements present an outstanding wide distribution among eukaryotes, from fishes to red algae, and can be even highly predominant within a large taxon, such as Malacostraca. Their distribution among crustaceans suggests a dynamics that follows a “domino days spreading” branching process in which successive amplifications may interact positively. PMID:23469217

  4. Nonlinear phased array imaging

    NASA Astrophysics Data System (ADS)

    Croxford, Anthony J.; Cheng, Jingwei; Potter, Jack N.

    2016-04-01

    A technique is presented for imaging acoustic nonlinearity within a specimen using ultrasonic phased arrays. Acoustic nonlinearity is measured by evaluating the difference in energy of the transmission bandwidth within the diffuse field produced through different focusing modes. The two different modes being classical beam forming, where delays are applied to different element of a phased array to physically focus the energy at a single location (parallel firing) and focusing in post processing, whereby one element at a time is fired and a focused image produced in post processing (sequential firing). Although these two approaches are linearly equivalent the difference in physical displacement within the specimen leads to differences in nonlinear effects. These differences are localized to the areas where the amplitude is different, essentially confining the differences to the focal point. Direct measurement at the focal point are however difficult to make. In order to measure this the diffuse field is used. It is a statistical property of the diffuse field that it represents the total energy in the system. If the energy in the diffuse field for both the sequential and parallel firing case is measured then the difference between these, within the input signal bandwidth, is largely due to differences at the focal spot. This difference therefore gives a localized measurement of where energy is moving out of the transmission bandwidth due to nonlinear effects. This technique is used to image fatigue cracks and other damage types undetectable with conventional linear ultrasonic measurements.

  5. Intramolecular and nonlinear dynamics

    SciTech Connect

    Davis, M.J.

    1993-12-01

    Research in this program focuses on three interconnected areas. The first involves the study of intramolecular dynamics, particularly of highly excited systems. The second area involves the use of nonlinear dynamics as a tool for the study of molecular dynamics and complex kinetics. The third area is the study of the classical/quantum correspondence for highly excited systems, particularly systems exhibiting classical chaos.

  6. Nonlinear optical inves

    NASA Astrophysics Data System (ADS)

    Zidan, M. D.; Arfan, A.; Allahham, A.

    2017-03-01

    Z-scan technique was used to investigate the nonlinear optical properties of Quinine and 1-(carboxymethyl)-6-methoxy-4-(3-(3-vinylpiperidin-4-yl) propanoyl) quinolin-1-ium chloride (Quinotoxine) salts. The two salts were characterized using UV-visible, FTIR and NMR measurements. The characterization spectra confirm the expected molecular structure of the prepared "Quinotoxine " salt. The z-scan measurements were performed with a CW Diode laser at 635 nm wavelength and 26 mW power. The nonlinear absorption coefficient (β), nonlinear refractive index (n2), the ground-state absorption cross sections (σg), the excited-state absorption cross sections (σex) and thermo-optic coefficient of the samples were determined. Our results reveal that the σex is higher than the σg indicating that the reverse saturable absorption (RSA) is the dominating mechanism for the observed absorption nonlinearities. The results suggest that this material should be considered as a promising candidate for future optical devices applications.

  7. Nonlinear silicon photonics

    NASA Astrophysics Data System (ADS)

    Tsia, Kevin K.; Jalali, Bahram

    2010-05-01

    An intriguing optical property of silicon is that it exhibits a large third-order optical nonlinearity, with orders-ofmagnitude larger than that of silica glass in the telecommunication band. This allows efficient nonlinear optical interaction at relatively low power levels in a small footprint. Indeed, we have witnessed a stunning progress in harnessing the Raman and Kerr effects in silicon as the mechanisms for enabling chip-scale optical amplification, lasing, and wavelength conversion - functions that until recently were perceived to be beyond the reach of silicon. With all the continuous efforts developing novel techniques, nonlinear silicon photonics is expected to be able to reach even beyond the prior achievements. Instead of providing a comprehensive overview of this field, this manuscript highlights a number of new branches of nonlinear silicon photonics, which have not been fully recognized in the past. In particular, they are two-photon photovoltaic effect, mid-wave infrared (MWIR) silicon photonics, broadband Raman effects, inverse Raman scattering, and periodically-poled silicon (PePSi). These novel effects and techniques could create a new paradigm for silicon photonics and extend its utility beyond the traditionally anticipated applications.

  8. Nonlinear plasmonic nanorulers.

    PubMed

    Butet, Jérémy; Martin, Olivier J F

    2014-05-27

    The evaluation of distances as small as few nanometers using optical waves is a very challenging task that can pave the way for the development of new applications in biotechnology and nanotechnology. In this article, we propose a new measurement method based on the control of the nonlinear optical response of plasmonic nanostructures by means of Fano resonances. It is shown that Fano resonances resulting from the coupling between a bright mode and a dark mode at the fundamental wavelength enable unprecedented and direct manipulation of the nonlinear electromagnetic sources at the nanoscale. In the case of second harmonic generation from gold nanodolmens, the different nonlinear sources distributions induced by the different coupling regimes are clearly revealed in the far-field distribution. Hence, the configuration of the nanostructure can be accurately determined in 3-dimensions by recording the wave scattered at the second harmonic wavelength. Indeed, the conformation of the different elements building the system is encoded in the nonlinear far-field distribution, making second harmonic generation a promising tool for reading 3-dimension plasmonic nanorulers. Furthemore, it is shown that 3-dimension plasmonic nanorulers can be implemented with simpler geometries than in the linear regime while providing complete information on the structure conformation, including the top nanobar position and orientation.

  9. Generalized Nonlinear Yule Models

    NASA Astrophysics Data System (ADS)

    Lansky, Petr; Polito, Federico; Sacerdote, Laura

    2016-11-01

    With the aim of considering models related to random graphs growth exhibiting persistent memory, we propose a fractional nonlinear modification of the classical Yule model often studied in the context of macroevolution. Here the model is analyzed and interpreted in the framework of the development of networks such as the World Wide Web. Nonlinearity is introduced by replacing the linear birth process governing the growth of the in-links of each specific webpage with a fractional nonlinear birth process with completely general birth rates. Among the main results we derive the explicit distribution of the number of in-links of a webpage chosen uniformly at random recognizing the contribution to the asymptotics and the finite time correction. The mean value of the latter distribution is also calculated explicitly in the most general case. Furthermore, in order to show the usefulness of our results, we particularize them in the case of specific birth rates giving rise to a saturating behaviour, a property that is often observed in nature. The further specialization to the non-fractional case allows us to extend the Yule model accounting for a nonlinear growth.

  10. Nonlinear Theory and Breakdown

    NASA Technical Reports Server (NTRS)

    Smith, Frank

    2007-01-01

    The main points of recent theoretical and computational studies on boundary-layer transition and turbulence are to be highlighted. The work is based on high Reynolds numbers and attention is drawn to nonlinear interactions, breakdowns and scales. The research focuses in particular on truly nonlinear theories, i.e. those for which the mean-flow profile is completely altered from its original state. There appear to be three such theories dealing with unsteady nonlinear pressure-displacement interactions (I), with vortex/wave interactions (II), and with Euler-scale flows (III). Specific recent findings noted for these three, and in quantitative agreement with experiments, are the following. Nonlinear finite-time break-ups occur in I, leading to sublayer eruption and vortex formation; here the theory agrees with experiments (Nishioka) regarding the first spike. II gives rise to finite-distance blowup of displacement thickness, then interaction and break-up as above; this theory agrees with experiments (Klebanoff, Nishioka) on the formation of three-dimensional streets. III leads to the prediction of turbulent boundary-layer micro-scale, displacement-and stress-sublayer-thicknesses.

  11. Nonlinear Image Denoising Methodologies

    DTIC Science & Technology

    2002-05-01

    53 5.3 A Multiscale Approach to Scale-Space Analysis . . . . . . . . . . . . . . . . 53 5.4...etc. In this thesis, Our approach to denoising is first based on a controlled nonlinear stochastic random walk to achieve a scale space analysis ( as in... stochastic treatment or interpretation of the diffusion. In addition, unless a specific stopping time is known to be adequate, the resulting evolution

  12. Robust adaptive dynamic programming and feedback stabilization of nonlinear systems.

    PubMed

    Jiang, Yu; Jiang, Zhong-Ping

    2014-05-01

    This paper studies the robust optimal control design for a class of uncertain nonlinear systems from a perspective of robust adaptive dynamic programming (RADP). The objective is to fill up a gap in the past literature of adaptive dynamic programming (ADP) where dynamic uncertainties or unmodeled dynamics are not addressed. A key strategy is to integrate tools from modern nonlinear control theory, such as the robust redesign and the backstepping techniques as well as the nonlinear small-gain theorem, with the theory of ADP. The proposed RADP methodology can be viewed as an extension of ADP to uncertain nonlinear systems. Practical learning algorithms are developed in this paper, and have been applied to the controller design problems for a jet engine and a one-machine power system.

  13. Nonlinear damping model for flexible structures. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Zang, Weijian

    1990-01-01

    The study of nonlinear damping problem of flexible structures is addressed. Both passive and active damping, both finite dimensional and infinite dimensional models are studied. In the first part, the spectral density and the correlation function of a single DOF nonlinear damping model is investigated. A formula for the spectral density is established with O(Gamma(sub 2)) accuracy based upon Fokker-Planck technique and perturbation. The spectral density depends upon certain first order statistics which could be obtained if the stationary density is known. A method is proposed to find the approximate stationary density explicitly. In the second part, the spectral density of a multi-DOF nonlinear damping model is investigated. In the third part, energy type nonlinear damping model in an infinite dimensional setting is studied.

  14. Aeroelastic Response of Nonlinear Wing Section by Functional Series Technique

    NASA Technical Reports Server (NTRS)

    Silva, Walter A.; Marzocca, Piergiovanni

    2001-01-01

    This paper addresses the problem of the determination of the subcritical aeroelastic response and flutter instability of nonlinear two-dimensional lifting surfaces in an incompressible flow-field via indicial functions and Volterra series approach. The related aeroelastic governing equations are based upon the inclusion of structural and damping nonlinearities in plunging and pitching, of the linear unsteady aerodynamics and consideration of an arbitrary time-dependent external pressure pulse. Unsteady aeroelastic nonlinear kernels are determined, and based on these, frequency and time histories of the subcritical aeroelastic response are obtained, and in this context the influence of the considered nonlinearities is emphasized. Conclusions and results displaying the implications of the considered effects are supplied.

  15. Aeroelastic Response of Nonlinear Wing Section By Functional Series Technique

    NASA Technical Reports Server (NTRS)

    Marzocca, Piergiovanni; Librescu, Liviu; Silva, Walter A.

    2000-01-01

    This paper addresses the problem of the determination of the subcritical aeroelastic response and flutter instability of nonlinear two-dimensional lifting surfaces in an incompressible flow-field via indicial functions and Volterra series approach. The related aeroelastic governing equations are based upon the inclusion of structural and damping nonlinearities in plunging and pitching, of the linear unsteady aerodynamics and consideration of an arbitrary time-dependent external pressure pulse. Unsteady aeroelastic nonlinear kernels are determined, and based on these, frequency and time histories of the subcritical aeroelastic response are obtained, and in this context the influence of the considered nonlinearities is emphasized. Conclusions and results displaying the implications of the considered effects are supplied.

  16. Asymptotic Stability of Interconnected Passive Non-Linear Systems

    NASA Technical Reports Server (NTRS)

    Isidori, A.; Joshi, S. M.; Kelkar, A. G.

    1999-01-01

    This paper addresses the problem of stabilization of a class of internally passive non-linear time-invariant dynamic systems. A class of non-linear marginally strictly passive (MSP) systems is defined, which is less restrictive than input-strictly passive systems. It is shown that the interconnection of a non-linear passive system and a non-linear MSP system is globally asymptotically stable. The result generalizes and weakens the conditions of the passivity theorem, which requires one of the systems to be input-strictly passive. In the case of linear time-invariant systems, it is shown that the MSP property is equivalent to the marginally strictly positive real (MSPR) property, which is much simpler to check.

  17. Nonlinear dynamics experiments

    SciTech Connect

    Fischer, W.

    2011-01-01

    The goal of nonlinear dynamics experiments is to improve the understanding of single particle effects that increase the particle amplitude and lead to loss. Particle motion in storage rings is nearly conservative and for transverse dynamics the Hamiltonian in action angle variables (I{sub x},I{sub y},{phi}{sub x},{phi}{sub y}) near an isolated resonance k{nu}{sub x} + l{nu}{sub y} {approx} p is H = I{sub x}{nu}{sub x0} + I{sub y}{nu}{sub y0} + g(I{sub x}, I{sub y}) + h(I{sub x}, I{sub y})cos(k{phi}{sub x} + l{phi}{sub y} - p{theta}), (1) where k, l, p are integers, {theta} = 2{pi}s/L is the azimuth, and s and L are the path length and circumference respectively. The amplitude dependent tunes are given by {nu}{sub x,y}(I{sub x},I{sub y}) = {nu}{sub x0,y0} + {partial_derivative}g(I{sub x},I{sub y})/{partial_derivative}I{sub x,y} (2) and h(I{sub x},I{sub y}) is the resonance driving term (RDT). If the motion is governed by multiple resonances, h(I{sub x},I{sub y}) has to be replace by a series of terms. The particle motion is completely determined by the terms g and h, which can be calculated from higher order multipoles (Sec. ??), or obtained from simulations. Deviations from pure Hamiltonian motion occur due to synchrotron radiation damping (Sec. ??) in lepton or very high energy hadron rings, parameter variations, and diffusion processes such as residual gas and intrabeam scattering. The time scale of the non-Hamiltonian process determines the applicability of the Hamiltonian analysis. Transverse nonlinearities are introduced through sextupoles or higher order multipoles and magnetic field errors in dipoles and quadrupoles. Sextupoles can already drive all resonances. The beam-beam interaction and space charge also introduce nonlinear fields. Intentionally introduced nonlinearities are used to extract beam on a resonance or through capture in stable islands. Localization and minimization of nonlinearities in a ring is a general strategy to decrease emittance growth

  18. Nonlinear indirect combustion noise for compact supercritical nozzle flows

    NASA Astrophysics Data System (ADS)

    Huet, M.

    2016-07-01

    In this paper, indirect combustion noise generated by the acceleration of entropy perturbations through a supercritical nozzle is investigated in the nonlinear regime and in the low-frequency limit (quasi-static hypothesis). This work completes the study of Huet and Giauque (Journal of Fluid Mechanics 733 (2013) 268-301) for nonlinear noise generation in nozzle flows without shock and particularly focuses on shocked flow regimes. It is based on the analytical model of Marble and Candel for compact nozzles (Journal of Sound and Vibration 55 (1977) 225-243), initially developed for excitations in the linear regime and rederived here for nonlinear perturbations. Full nonlinear analytical solutions are provided in the absence of shock as well as second-order analytical expressions when a shock is present in the diffuser. An analytical evaluation of the shock displacement inside the nozzle caused by the forcing is proposed and maximum possible forcings to avoid unchoke and 'over-choke' are discussed. The accuracy of the second-order model and the nonlinear contributions to the generated waves are then addressed. This model is found to be very accurate for the generated entropy wave with negligible nonlinear contributions. Nonlinearities are more visible, but still limited, for the downstream acoustic wave for large inlet Mach numbers. Analytical developments are validated thanks to comparisons with numerical simulations.

  19. Frequency addressable beams for land mobile communications

    NASA Technical Reports Server (NTRS)

    Thompson, J. D.; Dubellay, G. G.

    1988-01-01

    Satellites used for mobile communications need to serve large numbers of small, low cost terminals. The most important parameters affecting the capacity of such systems are the satellite equivalent isotropically radiated power (EIRP) and gain to noise temperature ratio (G/T) and available bandwidth. Satellites using frequency addressed beams provide high EIRP and G/T with high-gain antenna beams that also permit frequency reuse over the composite coverage area. Frequency addressing is easy to implement and compatible with low-cost terminals and offers higher capacity than alternative approaches.

  20. Shared address collectives using counter mechanisms

    DOEpatents

    Blocksome, Michael; Dozsa, Gabor; Gooding, Thomas M; Heidelberger, Philip; Kumar, Sameer; Mamidala, Amith R; Miller, Douglas

    2014-02-18

    A shared address space on a compute node stores data received from a network and data to transmit to the network. The shared address space includes an application buffer that can be directly operated upon by a plurality of processes, for instance, running on different cores on the compute node. A shared counter is used for one or more of signaling arrival of the data across the plurality of processes running on the compute node, signaling completion of an operation performed by one or more of the plurality of processes, obtaining reservation slots by one or more of the plurality of processes, or combinations thereof.

  1. Cheaper Adjoints by Reversing Address Computations

    DOE PAGES

    Hascoët, L.; Utke, J.; Naumann, U.

    2008-01-01

    The reverse mode of automatic differentiation is widely used in science and engineering. A severe bottleneck for the performance of the reverse mode, however, is the necessity to recover certain intermediate values of the program in reverse order. Among these values are computed addresses, which traditionally are recovered through forward recomputation and storage in memory. We propose an alternative approach for recovery that uses inverse computation based on dependency information. Address storage constitutes a significant portion of the overall storage requirements. An example illustrates substantial gains that the proposed approach yields, and we show use cases in practical applications.

  2. Dielectric Nonlinear Transmission Line (Postprint)

    DTIC Science & Technology

    2011-12-01

    Technical Paper 3. DATES COVERED (From - To) 2011 4. TITLE AND SUBTITLE Dielectric Nonlinear Transmission Line (POSTPRINT) 5a. CONTRACT NUMBER...14. ABSTRACT A parallel plate nonlinear transmission line (NLTL) was constructed. Periodic loading of nonlinear dielectric slabs provides the...846-9101 Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 Dielectric Nonlinear Transmission Line David M. French, Brad W. Hoff

  3. Neural learning of constrained nonlinear transformations

    NASA Technical Reports Server (NTRS)

    Barhen, Jacob; Gulati, Sandeep; Zak, Michail

    1989-01-01

    Two issues that are fundamental to developing autonomous intelligent robots, namely, rudimentary learning capability and dexterous manipulation, are examined. A powerful neural learning formalism is introduced for addressing a large class of nonlinear mapping problems, including redundant manipulator inverse kinematics, commonly encountered during the design of real-time adaptive control mechanisms. Artificial neural networks with terminal attractor dynamics are used. The rapid network convergence resulting from the infinite local stability of these attractors allows the development of fast neural learning algorithms. Approaches to manipulator inverse kinematics are reviewed, the neurodynamics model is discussed, and the neural learning algorithm is presented.

  4. Compactons in Nonlinear Schroedinger Lattices with Strong Nonlinearity Management

    SciTech Connect

    Abdullaev, F. Kh.; Kevrekidis, P. G.; Salerno, M.

    2010-09-10

    The existence of compactons in the discrete nonlinear Schroedinger equation in the presence of fast periodic time modulations of the nonlinearity is demonstrated. In the averaged discrete nonlinear Schroedinger equation, the resulting effective interwell tunneling depends on the modulation parameters and on the field amplitude. This introduces nonlinear dispersion in the system and can lead to a prototypical realization of single- or multisite stable discrete compactons in nonlinear optical waveguide and Bose-Einstein condensate arrays. These structures can dynamically arise out of Gaussian or compactly supported initial data.

  5. Program for Nonlinear Structural Analysis

    DTIC Science & Technology

    1981-09-01

    November 1970. 2. R. E. Jones and W. L. Salus , "Survey and Development of Finite Elements for Nonlineer Structural Analysis", Volume II, "Nonlinear Shell...1970. 2. R. E. Jones and W. L. Salus , "Survey and Development of Finite Elements for Nonlinear Structural Analysis," Volume II, "Nonlinear Shell

  6. Cubication of Conservative Nonlinear Oscillators

    ERIC Educational Resources Information Center

    Belendez, Augusto; Alvarez, Mariela L.; Fernandez, Elena; Pascual, Immaculada

    2009-01-01

    A cubication procedure of the nonlinear differential equation for conservative nonlinear oscillators is analysed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force, and this allows us to approximate the original nonlinear differential equation by a Duffing equation in which the coefficients for the linear…

  7. Nonlinear electrostatic drift Kelvin-Helmholtz instability

    NASA Technical Reports Server (NTRS)

    Sharma, Avadhesh C.; Srivastava, Krishna M.

    1993-01-01

    Nonlinear analysis of electrostatic drift Kelvin-Helmholtz instability is performed. It is shown that the analysis leads to the propagation of the weakly nonlinear dispersive waves, and the nonlinear behavior is governed by the nonlinear Burger's equation.

  8. Naming and Address in Afghan Society.

    ERIC Educational Resources Information Center

    Miran, M. Alam

    Forms of address in Afghan society reflect the relationships between the speakers as well as the society's structure. In Afghan Persian, or Dari, first, second, and last names have different semantic dimensions. Boys' first names usually consist of two parts or morphemes, of which one may be part of the father's name. Girls' names usually consist…

  9. Problem Solvers: Solutions--The Inaugural Address

    ERIC Educational Resources Information Center

    Dause, Emily

    2014-01-01

    Fourth graders in Miss Dause's and Mrs. Hicks's mathematics classes at South Mountain Elementary School in Dillsburg, Pennsylvania, worked with the data from the Inauagural Address problem that was previously published published in the February 2013 issue of "Teaching Children Mathematics". This activity allowed students to showcase…

  10. 21 CFR 600.2 - Mailing addresses.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Mailing addresses. 600.2 Section 600.2 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... (HFM-99), Center for Biologics Evaluation and Research, Food and Drug Administration, 1401...

  11. 21 CFR 600.2 - Mailing addresses.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Mailing addresses. 600.2 Section 600.2 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... (HFM-99), Center for Biologics Evaluation and Research, Food and Drug Administration, 1401...

  12. 21 CFR 600.2 - Mailing addresses.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Mailing addresses. 600.2 Section 600.2 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS... (HFM-99), Center for Biologics Evaluation and Research, Food and Drug Administration, 1401...

  13. Transition through Teamwork: Professionals Address Student Access

    ERIC Educational Resources Information Center

    Bube, Sue Ann; Carrothers, Carol; Johnson, Cinda

    2016-01-01

    Prior to 2013, there was no collaboration around the transition services for deaf and hard of hearing students in Washington State. Washington had numerous agencies providing excellent support, but those agencies were not working together. It was not until January 29, 2013, when pepnet 2 hosted the Building State Capacity to Address Critical…

  14. Addressing Student Debt in the Classroom

    ERIC Educational Resources Information Center

    Perkins, David; Johnston, Tim; Lytle, Rick

    2016-01-01

    Student debt is a national concern. The authors address debt in the classroom to enhance students' understanding of the consequences of debt and the need for caution when financing their education. However, student feedback indicates this understanding has a delayed effect on borrowing behavior and underscores the importance of making difficult…

  15. Preservice Educators' Confidence in Addressing Sexuality Education

    ERIC Educational Resources Information Center

    Wyatt, Tammy Jordan

    2009-01-01

    This study examined 328 preservice educators' level of confidence in addressing four sexuality education domains and 21 sexuality education topics. Significant differences in confidence levels across the four domains were found for gender, academic major, sexuality education philosophy, and sexuality education knowledge. Preservice educators…

  16. Native Women at Risk: Addressing Cancer Prevention.

    ERIC Educational Resources Information Center

    Thiemann, Kay M. B.

    1994-01-01

    Discusses outcomes of a conference that brought together representatives from Indian tribes, state health departments, the Indian Health Service, the Mayo Clinic, and the American Cancer Society, to address the high rate of cervical cancer among American Indian women. Describes barriers to health care and plans to promote cancer screening among…

  17. 50 CFR 18.78 - Mailing address.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Mailing address. 18.78 Section 18.78 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED... PLANTS (CONTINUED) MARINE MAMMALS Notice and Hearing on Section 103 Regulations § 18.78 Mailing...

  18. 34 CFR 674.44 - Address searches.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION FEDERAL PERKINS LOAN PROGRAM Due Diligence § 674.44 Address searches. (a) If mail... litigation; (2) The account is assigned to the United States; or (3) The account is written off under §...

  19. Address Systems in "The Plum Plum Pickers"

    ERIC Educational Resources Information Center

    Geuder, Patricia A.

    1975-01-01

    The address systems in Raymond Barrio's "The Plum Plum Pickers" imply sociolinguistic differences between the Chicano and the Anglo characters. The kinds of sociolinguistic situations, the number of dyadic patterns, and the quantity of the dyadic patterns strongly suggest the differences. (Author)

  20. Addressing Psychosocial Factors with Library Mentoring

    ERIC Educational Resources Information Center

    Farrell, Bridget; Alabi, Jaena; Whaley, Pambanisha; Jenda, Claudine

    2017-01-01

    The majority of articles on mentoring in the library and information science field address career development by emphasizing the orientation process for new librarians and building the requisite skills for a specific job. Few articles deal with the psychological and social challenges that many early-career and minority librarians face, which can…

  1. Registering Names and Addresses for Information Technology.

    ERIC Educational Resources Information Center

    Knapp, Arthur A.

    The identification of administrative authorities and the development of associated procedures for registering and accessing names and addresses of communications data systems are considered in this paper. It is noted that, for data communications systems using standards based on the Open Systems Interconnection (OSI) Reference Model specified by…

  2. Addressing South Africa's Engineering Skills Gaps

    ERIC Educational Resources Information Center

    Hall, Jonathan; Sandelands, Eric

    2009-01-01

    Purpose: This paper aims to provide a case study of how engineering skills gaps are being addressed by Murray & Roberts in South Africa. Design/methodology/approach: The paper focuses on skills challenges in South Africa from a reflective practitioner perspective, exploring a case example from an industry leader. Findings: The paper explores…

  3. Rational Rhymes for Addressing Common Childhood Issues

    ERIC Educational Resources Information Center

    Warren, Jeffrey M.

    2011-01-01

    Music-based interventions are valuable tools counselors can use when working with children. Specific types of music-based interventions, such as songs or rhymes, can be especially pertinent in addressing the thoughts, feelings, and behaviors of children. Rational-emotive behavior therapy (REBT) provides a therapeutic framework that encourages…

  4. How Sociology Texts Address Gun Control

    ERIC Educational Resources Information Center

    Tonso, William R.

    2004-01-01

    William R. Tonso has chosen an issue that he knows something about to examine how sociology textbooks address controversy. Appealing for gun control is fashionable, but it is at odds with a fondness that ordinary Americans have for their firearms--one that is supported by a growing body of research on deterrence to crime. There are two sides to…

  5. Addressing Issues Related to Technology and Engineering

    ERIC Educational Resources Information Center

    Technology Teacher, 2008

    2008-01-01

    This article presents an interview with Michael Hacker and David Burghardt, codirectors of Hoftra University's Center for Technological Literacy. Hacker and Burghardt address issues related to technology and engineering. They argue that teachers need to be aware of the problems kids are facing, and how to present these problems in an engaging…

  6. 40 CFR 98.9 - Addresses.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... submitted to the following address: (a) For U.S. mail. Director, Climate Change Division, 1200 Pennsylvania Ave., NW., Mail Code: 6207J, Washington, DC 20460. (b) For package deliveries. Director, Climate Change Division, 1310 L St, NW., Washington, DC 20005....

  7. 40 CFR 98.9 - Addresses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... submitted to the following address: (a) For U.S. mail. Director, Climate Change Division, 1200 Pennsylvania Ave., NW., Mail Code: 6207J, Washington, DC 20460. (b) For package deliveries. Director, Climate Change Division, 1310 L St, NW., Washington, DC 20005....

  8. 40 CFR 80.174 - Addresses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.174 Addresses. (a) The detergent additive sample..., 2565 Plymouth Road, Ann Arbor, Michigan 48105. (b) Other detergent registration and certification data, and certain other information which may be specified in this subpart, shall be sent to:...

  9. 40 CFR 80.174 - Addresses.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.174 Addresses. (a) The detergent additive sample..., 2565 Plymouth Road, Ann Arbor, Michigan 48105. (b) Other detergent registration and certification data, and certain other information which may be specified in this subpart, shall be sent to:...

  10. 78 FR 35149 - Addresses of Regional Offices

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR... Addresses of Regional Offices AGENCY: Fish and Wildlife Service, Interior. ACTION: Final rule. SUMMARY: We... offices in our regulations at title 50 of the Code of Federal Regulations. We are also making...

  11. EPA Addresses Environmental Justice in Houston

    EPA Pesticide Factsheets

    DALLAS - (Oct. 8, 2015) Today, the U.S. Environmental Protection Agency (EPA) announced Texas Environmental Justice Advocacy Services (t.e.j.a.s.) was selected as a grant recipient to address environmental justice (EJ) issues in the Manchester area

  12. Federal Offices That Address Women's Issues.

    ERIC Educational Resources Information Center

    Weber, Patricia A.; And Others

    This directory contains a listing of federal offices that address women's issues. Among the departments and agencies included are: the executive branch and the executive agencies departments of agriculture, commerce, defense (Air Force, Army, Coast Guard, Marine Corps, National Guard and Navy), education, health and human services, housing and…

  13. 37 CFR 301.2 - Official addresses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: Copyright Royalty Board, P.O. Box 70977, Southwest Station, Washington, DC 20024-0977. (b) If hand delivered... Building, 101 Independence Avenue, SE., Washington, DC 20559-6000. (c) If hand delivered by a commercial...., Washington, DC, Monday through Friday, between 8:30 a.m. and 4 p.m., and be addressed as follows:...

  14. 37 CFR 301.2 - Official addresses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Copyright Royalty Board, P.O. Box 70977, Southwest Station, Washington, DC 20024-0977. (b) If hand delivered... Building, 101 Independence Avenue, SE., Washington, DC 20559-6000. (c) If hand delivered by a commercial...., Washington, DC, Monday through Friday, between 8:30 a.m. and 4 p.m., and be addressed as follows:...

  15. Autocheck: Addressing the Problem of Rural Transportation.

    ERIC Educational Resources Information Center

    Payne, Guy A.

    This paper describes a project implemented by a social worker from the Glynn County School District in rural Georgia to address transportation problems experienced by students and their families. The project aims to assist families who are unable to keep appointments or attend other important events due to unreliable transportation. A county needs…

  16. 40 CFR 80.174 - Addresses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.174 Addresses. (a) The detergent additive sample..., 2565 Plymouth Road, Ann Arbor, Michigan 48105. (b) Other detergent registration and certification data, and certain other information which may be specified in this subpart, shall be sent to:...

  17. 40 CFR 80.174 - Addresses.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.174 Addresses. (a) The detergent additive sample..., 2565 Plymouth Road, Ann Arbor, Michigan 48105. (b) Other detergent registration and certification data, and certain other information which may be specified in this subpart, shall be sent to:...

  18. Addressing Deaf Culture in the Classroom.

    ERIC Educational Resources Information Center

    Pagliaro, Claudia

    2001-01-01

    The importance of recognizing the culture of deaf people is often overlooked when addressing issues of student diversity in the schools. Including the culture of deaf students can add vitality and energy to the educational environment, providing an alternative and unique perspective. This paper describes deafness, explains deaf culture, and…

  19. 50 CFR 228.8 - Mailing address.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Mailing address. 228.8 Section 228.8 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION... the Presiding Officer, c/o Assistant Administrator, National Marine Fisheries Service, 1315...

  20. Mapping virtual addresses to different physical addresses for value disambiguation for thread memory access requests

    DOEpatents

    Gala, Alan; Ohmacht, Martin

    2014-09-02

    A multiprocessor system includes nodes. Each node includes a data path that includes a core, a TLB, and a first level cache implementing disambiguation. The system also includes at least one second level cache and a main memory. For thread memory access requests, the core uses an address associated with an instruction format of the core. The first level cache uses an address format related to the size of the main memory plus an offset corresponding to hardware thread meta data. The second level cache uses a physical main memory address plus software thread meta data to store the memory access request. The second level cache accesses the main memory using the physical address with neither the offset nor the thread meta data after resolving speculation. In short, this system includes mapping of a virtual address to a different physical addresses for value disambiguation for different threads.

  1. Optothermal nonlinearity of silica aerogel

    NASA Astrophysics Data System (ADS)

    Braidotti, Maria Chiara; Gentilini, Silvia; Fleming, Adam; Samuels, Michiel C.; Di Falco, Andrea; Conti, Claudio

    2016-07-01

    We report on the characterization of silica aerogel thermal optical nonlinearity, obtained by z-scan technique. The results show that typical silica aerogels have nonlinear optical coefficient similar to that of glass (≃10-12 m2/W), with negligible optical nonlinear absorption. The nonlinear coefficient can be increased to values in the range of 10-10 m2/W by embedding an absorbing dye in the aerogel. This value is one order of magnitude higher than that observed in the pure dye and in typical highly nonlinear materials like liquid crystals.

  2. Nonlinear computer-generated holograms

    NASA Astrophysics Data System (ADS)

    Shapira, Asia; Juwiler, Irit; Arie, Ady

    2011-08-01

    We propose a novel technique for arbitrary wavefront shaping in quadratic nonlinear crystals by introducing the concept of computer-generated holograms (CGHs) into the nonlinear optical regime. We demonstrate the method experimentally showing a conversion of a fundamental Gaussian beam pump light into the first three Hermite--Gaussian beams at the second harmonic in a stoichiometric lithium tantalate nonlinear crystal, and we characterize its efficiency dependence on the fundamental power and the crystal temperature. Nonlinear CGHs open new possibilities in the fields of nonlinear beam shaping, mode conversion, and beam steering.

  3. Volterra Series Approach for Nonlinear Aeroelastic Response of 2-D Lifting Surfaces

    NASA Technical Reports Server (NTRS)

    Silva, Walter A.; Marzocca, Piergiovanni; Librescu, Liviu

    2001-01-01

    The problem of the determination of the subcritical aeroelastic response and flutter instability of nonlinear two-dimensional lifting surfaces in an incompressible flow-field via Volterra series approach is addressed. The related aeroelastic governing equations are based upon the inclusion of structural nonlinearities, of the linear unsteady aerodynamics and consideration of an arbitrary time-dependent external pressure pulse. Unsteady aeroelastic nonlinear kernels are determined, and based on these, frequency and time histories of the subcritical aeroelastic response are obtained, and in this context the influence of geometric nonlinearities is emphasized. Conclusions and results displaying the implications of the considered effects are supplied.

  4. Nonlinear metamaterials for holography

    NASA Astrophysics Data System (ADS)

    Almeida, Euclides; Bitton, Ora; Prior, Yehiam

    2016-08-01

    A hologram is an optical element storing phase and possibly amplitude information enabling the reconstruction of a three-dimensional image of an object by illumination and scattering of a coherent beam of light, and the image is generated at the same wavelength as the input laser beam. In recent years, it was shown that information can be stored in nanometric antennas giving rise to ultrathin components. Here we demonstrate nonlinear multilayer metamaterial holograms. A background free image is formed at a new frequency--the third harmonic of the illuminating beam. Using e-beam lithography of multilayer plasmonic nanoantennas, we fabricate polarization-sensitive nonlinear elements such as blazed gratings, lenses and other computer-generated holograms. These holograms are analysed and prospects for future device applications are discussed.

  5. Nonlinear metamaterials for holography

    PubMed Central

    Almeida, Euclides; Bitton, Ora

    2016-01-01

    A hologram is an optical element storing phase and possibly amplitude information enabling the reconstruction of a three-dimensional image of an object by illumination and scattering of a coherent beam of light, and the image is generated at the same wavelength as the input laser beam. In recent years, it was shown that information can be stored in nanometric antennas giving rise to ultrathin components. Here we demonstrate nonlinear multilayer metamaterial holograms. A background free image is formed at a new frequency—the third harmonic of the illuminating beam. Using e-beam lithography of multilayer plasmonic nanoantennas, we fabricate polarization-sensitive nonlinear elements such as blazed gratings, lenses and other computer-generated holograms. These holograms are analysed and prospects for future device applications are discussed. PMID:27545581

  6. Nonlinear Magnetic Beach

    NASA Astrophysics Data System (ADS)

    Arefiev, A.; Breizman, B.

    2000-10-01

    The ion response to the rf-field in the magnetic beach problem can be essentially nonlinear. This paper presents a self-consistent theory of the rf-wave propagation and ion motion through the ion cyclotron resonance. An important ingredient of the problem is the ion flow along the magnetic field. The flow velocity limits the time the ions spend at the resonance, which in turn limits the ion energy gain. A feature that makes the problem nonlinear is that the flow accelerates under the effect of the grad B force and rf-pressure. This acceleration can produce a steep decrease in the plasma density at the resonance, resulting in partial reflection of the incident wave. *Work supported by VASIMR project at NASA and by U.S. DOE Contract DE-FG03-96ER-54346.

  7. Nonlinear Photonics 2014: introduction.

    PubMed

    Akhmediev, N; Kartashov, Yaroslav

    2015-01-12

    International Conference "Nonlinear Photonics-2014" took place in Barcelona, Spain on July 27-31, 2014. It was a part of the "Advanced Photonics Congress" which is becoming a traditional notable event in the world of photonics. The current focus issue of Optics Express contains contributions from the participants of the Conference and the Congress. The articles in this focus issue by no means represent the total number of the congress contributions (around 400). However, it demonstrates wide range of topics covered at the event. The next conference of this series is to be held in 2016 in Australia, which is the home of many researchers working in the field of photonics in general and nonlinear photonics in particular.

  8. Augmented nonlinear differentiator design

    NASA Astrophysics Data System (ADS)

    Shao, Xingling; Liu, Jun; Yang, Wei; Tang, Jun; Li, Jie

    2017-06-01

    This paper presents a sigmoid function based augmented nonlinear differentiator (AND) for calculating the noise-less time derivative from a noisy measurement. The prominent advantages of the present differentiation technique are: (i) compared to the existing tracking differentiators, better noise suppression ability can be achieved without appreciable delay; (ii) the enhanced noise-filtering mechanism not only can be applied to the designed differentiator, but also can be extended for improving noise-tolerance capability of the available differentiators. In addition, the convergence property and robustness performance against noises are investigated via singular perturbation theory and describing function method, respectively. Also, comparison with several classical differentiators is given to illustrate the superiority of AND in noise suppression. Finally, applications on autopilot design and displacement following for nonlinear mass spring mechanical system are given to demonstrate the effectiveness and applicability of the proposed AND technique.

  9. Nonlinear differential equations

    SciTech Connect

    Dresner, L.

    1988-01-01

    This report is the text of a graduate course on nonlinear differential equations given by the author at the University of Wisconsin-Madison during the summer of 1987. The topics covered are: direction fields of first-order differential equations; the Lie (group) theory of ordinary differential equations; similarity solutions of second-order partial differential equations; maximum principles and differential inequalities; monotone operators and iteration; complementary variational principles; and stability of numerical methods. The report should be of interest to graduate students, faculty, and practicing scientists and engineers. No prior knowledge is required beyond a good working knowledge of the calculus. The emphasis is on practical results. Most of the illustrative examples are taken from the fields of nonlinear diffusion, heat and mass transfer, applied superconductivity, and helium cryogenics.

  10. Nonlinear terahertz superconducting plasmonics

    NASA Astrophysics Data System (ADS)

    Wu, Jingbo; Zhang, Caihong; Liang, Lanju; Jin, Biaobing; Kawayama, Iwao; Murakami, Hironaru; Kang, Lin; Xu, Weiwei; Wang, Huabing; Chen, Jian; Tonouchi, Masayoshi; Wu, Peiheng

    2014-10-01

    Nonlinear terahertz (THz) transmission through subwavelength hole array in superconducting niobium nitride (NbN) film is experimentally investigated using intense THz pulses. The good agreement between the measurement and numerical simulations indicates that the field strength dependent transmission mainly arises from the nonlinear properties of the superconducting film. Under weak THz pulses, the transmission peak can be tuned over a frequency range of 145 GHz which is attributed to the high kinetic inductance of 50 nm-thick NbN film. Utilizing the THz pump-THz probe spectroscopy, we study the dynamic process of transmission spectra and demonstrate that the transition time of such superconducting plasmonic device is within 5 ps.

  11. Research in nonlinear structural and solid mechanics

    NASA Technical Reports Server (NTRS)

    Mccomb, H. G., Jr. (Compiler); Noor, A. K. (Compiler)

    1980-01-01

    Nonlinear analysis of building structures and numerical solution of nonlinear algebraic equations and Newton's method are discussed. Other topics include: nonlinear interaction problems; solution procedures for nonlinear problems; crash dynamics and advanced nonlinear applications; material characterization, contact problems, and inelastic response; and formulation aspects and special software for nonlinear analysis.

  12. Nonlinear Guided Waves

    DTIC Science & Technology

    1991-08-19

    experiments," contributed paper, topical meeting on Integrated Photonics , Hilton Head (1990). 20. S. Trillo, S. Wabnitz, B. Diano, and E. M. Wright...34Picosecond pulse switching in semiconductor active nonlinear directional couplers," contributed paper, topical meeting on Integrated Photonics , Hilton...meeting on Integrated Photonics , Hilton Head (1990). 22. E. M. Wright, "Amplifier and laser switches," invited paper, workshop on Semiconductor Laser

  13. Nonlinear Neural Network Oscillator.

    DTIC Science & Technology

    A nonlinear oscillator (10) includes a neural network (12) having at least one output (12a) for outputting a one dimensional vector. The neural ... neural network and the input of the input layer for modifying a magnitude and/or a polarity of the one dimensional output vector prior to the sample of...first or a second direction. Connection weights of the neural network are trained on a deterministic sequence of data from a chaotic source or may be a

  14. Mathematical Nonlinear Optics

    DTIC Science & Technology

    1998-09-11

    34Evolution of Bloch electrons with Applied Electromagnetic Fields: the Semiclassical Equations ", European Jour- nal of Applied Mathematics (1996...establishment (with Jalal Shatah) of the existence of homoclinic orbits with complex spa- tial structure for perturbed NLS equations . This existence...a very small amount of diffraction. (v) McLaughlin (with T. Ueda) have in progress a study of precursors for model nonlinear wave equations . This

  15. Mathematical Nonlinear Optics

    DTIC Science & Technology

    1994-01-03

    August, 1991. Thesis - "Applications of the Inverse Spectral Transform to a Korteweg - DeVries Equation with a Kuramoto-Sivashinsky-Type Perturbation... equations , the mathematical theory of nematic optics involves strong coupling between the electromagnetic and nematic director (molecular orientation... equations for the electric field E coupled to a nonlinear parabolic equation for the director n, a field of unit vectors which describes the local molecular

  16. Surface nonlinear optics

    SciTech Connect

    Shen, Y.R.; Chen, C.K.; de Castro, A.R.B.

    1980-01-01

    Surface electromagnetic waves are waves propagating along the interface of two media. Their existence was predicted by Sommerfield in 1909. In recent years, interesting applications have been found in the study of overlayers and molecular adsorption on surfaces, in probing of phase transitions, and in measurements of refractive indices. In the laboratory, the nonlinear interaction of surface electromagnetic waves were studied. The preliminary results of this recent venture in this area are presented.

  17. Nonlinear Wave Propagation

    DTIC Science & Technology

    2009-02-09

    of parameters. Hence one expects that the solutions of the two equations , PES and NLS, are comparable. In Fig. 3 we plot the two solutions for...power saturated term, in the PES equation ) have stable soliton solutions or mode-locking evolution. In general the solitons are found to be unstable...literature. Generally speaking, the above lattice equations omitting nonlinear terms have solutions propagating along z direction, i.e., ψ(r, z) = e−iµzϕ(r

  18. Nonlinear Wave Propagation

    DTIC Science & Technology

    1983-12-30

    Equation * Discrete IST and numerical simulations * Long time asymptotic solutions of nonlinear evolution equations * Painlevf equations . Focussing...larger class of solutions io KdV than does the Gel’fand-’Levitan equation . Specifically we have shown by direct calculation that if 0(k;x,t) solves oV...Investigation of the full generality of the solutions of KdV via this new formulation. (b) Developnent of similar types - integral equations for

  19. Nonlinear Wave Propagation.

    DTIC Science & Technology

    1987-11-23

    generalized wave equation (GWE) when (z) 0 (1-Z2)/2: - X(z). (1.5) The compatibility condition required for the existence of solutions to these B~icklund...Phys. tion of a class of nonlocal nonlinear evolution equations , A 15 (1982) 781. INS *47, Clarkson University (1985), to be published in J. Math... semilinear form. The above approach will fail if there exist linearizable quasilinear equations which can not be mapped to a semilinear from. It is shown in

  20. Cognitive Nonlinear Radar

    DTIC Science & Technology

    2013-01-01

    Devices and Method for Detecting Emplacement of Improvised Explosive Devices, U. S. Patent 7,680,599, Mar. 16, 2010. 11. Steele, D.; Rotondo, F.; Houck...Patent 7,987,068, Jul. 26, 2011. 9 14. Keller, W. Active Improvised Explosive Device (IED) Electronic Signature Detection , U. S. Patent...operate without interfering with each other. The CNR uses a narrowband, nonlinear radar target detection methodology. This methodology has the advantage

  1. Filamentation with nonlinear Bessel vortices.

    PubMed

    Jukna, V; Milián, C; Xie, C; Itina, T; Dudley, J; Courvoisier, F; Couairon, A

    2014-10-20

    We present a new type of ring-shaped filaments featured by stationary nonlinear high-order Bessel solutions to the laser beam propagation equation. Two different regimes are identified by direct numerical simulations of the nonlinear propagation of axicon focused Gaussian beams carrying helicity in a Kerr medium with multiphoton absorption: the stable nonlinear propagation regime corresponds to a slow beam reshaping into one of the stationary nonlinear high-order Bessel solutions, called nonlinear Bessel vortices. The region of existence of nonlinear Bessel vortices is found semi-analytically. The influence of the Kerr nonlinearity and nonlinear losses on the beam shape is presented. Direct numerical simulations highlight the role of attractors played by nonlinear Bessel vortices in the stable propagation regime. Large input powers or small cone angles lead to the unstable propagation regime where nonlinear Bessel vortices break up into an helical multiple filament pattern or a more irregular structure. Nonlinear Bessel vortices are shown to be sufficiently intense to generate a ring-shaped filamentary ionized channel in the medium which is foreseen as opening the way to novel applications in laser material processing of transparent dielectrics.

  2. Nonlinear gyrokinetic equations

    SciTech Connect

    Dubin, D.H.E.; Krommes, J.A.; Oberman, C.; Lee, W.W.

    1983-03-01

    Nonlinear gyrokinetic equations are derived from a systematic Hamiltonian theory. The derivation employs Lie transforms and a noncanonical perturbation theory first used by Littlejohn for the simpler problem of asymptotically small gyroradius. For definiteness, we emphasize the limit of electrostatic fluctuations in slab geometry; however, there is a straight-forward generalization to arbitrary field geometry and electromagnetic perturbations. An energy invariant for the nonlinear system is derived, and various of its limits are considered. The weak turbulence theory of the equations is examined. In particular, the wave kinetic equation of Galeev and Sagdeev is derived from an asystematic truncation of the equations, implying that this equation fails to consider all gyrokinetic effects. The equations are simplified for the case of small but finite gyroradius and put in a form suitable for efficient computer simulation. Although it is possible to derive the Terry-Horton and Hasegawa-Mima equations as limiting cases of our theory, several new nonlinear terms absent from conventional theories appear and are discussed.

  3. Is this scaling nonlinear?

    PubMed Central

    2016-01-01

    One of the most celebrated findings in complex systems in the last decade is that different indexes y (e.g. patents) scale nonlinearly with the population x of the cities in which they appear, i.e. y∼xβ,β≠1. More recently, the generality of this finding has been questioned in studies that used new databases and different definitions of city boundaries. In this paper, we investigate the existence of nonlinear scaling, using a probabilistic framework in which fluctuations are accounted for explicitly. In particular, we show that this allows not only to (i) estimate β and confidence intervals, but also to (ii) quantify the evidence in favour of β≠1 and (iii) test the hypothesis that the observations are compatible with the nonlinear scaling. We employ this framework to compare five different models to 15 different datasets and we find that the answers to points (i)–(iii) crucially depend on the fluctuations contained in the data, on how they are modelled, and on the fact that the city sizes are heavy-tailed distributed. PMID:27493764

  4. Quantum well nonlinear microcavities

    NASA Astrophysics Data System (ADS)

    Oudar, J. L.; Kuszelewicz, R.; Sfez, B.; Pellat, D.; Azoulay, R.

    We report on recent progress in reducing the power threshold of all-optical bistable quantum well vertical microcavities. Significant improvements are achieved through an increase of the cavity finesse, together with a reduction of the device active layer thickness. A critical intensity of 5 μW/μm 2 has been observed on a microcavity of finesse 250, with a nonlinear medium of only 18 GaAs quantum wells of 10 nm thickness. Further improvements of the Bragg mirror quality resulted in a finesse of 700 and a power-lifetime product of 15 fJ/μm 2. Microresonator pixellation allows to obtain 2-dimensional arrays. A thermally-induced alloy-mixing technique is described, which produced a 110 meV carrier confinement energy, together with a refractive index change of -.012, averaged over the 2.6 μm nonlinear medium thickness. The resulting electrical and optical confinement is shown to improve the nonlinear characteristics, by limiting lateral carrier diffusion and light diffraction.

  5. Image Coding Based on Address Vector Quantization.

    NASA Astrophysics Data System (ADS)

    Feng, Yushu

    Image coding is finding increased application in teleconferencing, archiving, and remote sensing. This thesis investigates the potential of Vector Quantization (VQ), a relatively new source coding technique, for compression of monochromatic and color images. Extensions of the Vector Quantization technique to the Address Vector Quantization method have been investigated. In Vector Quantization, the image data to be encoded are first processed to yield a set of vectors. A codeword from the codebook which best matches the input image vector is then selected. Compression is achieved by replacing the image vector with the index of the code-word which produced the best match, the index is sent to the channel. Reconstruction of the image is done by using a table lookup technique, where the label is simply used as an address for a table containing the representative vectors. A code-book of representative vectors (codewords) is generated using an iterative clustering algorithm such as K-means, or the generalized Lloyd algorithm. A review of different Vector Quantization techniques are given in chapter 1. Chapter 2 gives an overview of codebook design methods including the Kohonen neural network to design codebook. During the encoding process, the correlation of the address is considered and Address Vector Quantization is developed for color image and monochrome image coding. Address VQ which includes static and dynamic processes is introduced in chapter 3. In order to overcome the problems in Hierarchical VQ, Multi-layer Address Vector Quantization is proposed in chapter 4. This approach gives the same performance as that of the normal VQ scheme but the bit rate is about 1/2 to 1/3 as that of the normal VQ method. In chapter 5, a Dynamic Finite State VQ based on a probability transition matrix to select the best subcodebook to encode the image is developed. In chapter 6, a new adaptive vector quantization scheme, suitable for color video coding, called "A Self -Organizing

  6. Apparatus for generating nonlinear pulse patterns

    DOEpatents

    Nakamura, N.M.I.

    Apparatus for generating a plurality of nonlinear pulse patterns from a single linear pulse pattern. A first counter counts the pulses of the linear pulse pattern and a second counter counts the pulses of the nonlinear pulse pattern. A comparator compares the counts of both counters, and in response to an equal count, a gate is enabled to gate a pulse of the linear pattern as a pulse of the nonlinear pattern, the latter also resetting the first counter. Presettable dividers divide the pulses of each pattern before they are counted by the respective counters. Apparatus for generating a logarithmic pulse pattern from a linear pulse pattern to any log base is described. In one embodiment, a shift register is used in place of the second counter to be clocked by each pulse of the logarithmic pattern to generate the pattern. In another embodiment, a memory stores the logarithmic pattern and is addressed by the second counter which is clocked by the pulses of the logarithmic pulse pattern.

  7. Apparatus for generating nonlinear pulse patterns

    DOEpatents

    Nakamura, Michiyuki

    1981-01-01

    Apparatus for generating a plurality of nonlinear pulse patterns from a single linear pulse pattern. A first counter counts the pulses of the linear pulse pattern and a second counter counts the pulses of the nonlinear pulse pattern. A comparator compares the counts of both counters, and in response to an equal count, a gate is enabled to gate a pulse of the linear pattern as a pulse of the nonlinear pattern, the latter also resetting the first counter. Presettable dividers divide the pulses of each pattern before they are counted by the respective counters. Also, apparatus for generating a logarithmic pulse pattern from a linear pulse pattern to any log base. In one embodiment, a shift register is used in place of the second counter to be clocked by each pulse of the logarithmic pattern to generate the pattern. In another embodiment, a memory stores the logarithmic pattern and is addressed by the second counter which is clocked by the pulses of the logarithmic pulse pattern.

  8. Ranking scientific publications: the effect of nonlinearity

    NASA Astrophysics Data System (ADS)

    Yao, Liyang; Wei, Tian; Zeng, An; Fan, Ying; di, Zengru

    2014-10-01

    Ranking the significance of scientific publications is a long-standing challenge. The network-based analysis is a natural and common approach for evaluating the scientific credit of papers. Although the number of citations has been widely used as a metric to rank papers, recently some iterative processes such as the well-known PageRank algorithm have been applied to the citation networks to address this problem. In this paper, we introduce nonlinearity to the PageRank algorithm when aggregating resources from different nodes to further enhance the effect of important papers. The validation of our method is performed on the data of American Physical Society (APS) journals. The results indicate that the nonlinearity improves the performance of the PageRank algorithm in terms of ranking effectiveness, as well as robustness against malicious manipulations. Although the nonlinearity analysis is based on the PageRank algorithm, it can be easily extended to other iterative ranking algorithms and similar improvements are expected.

  9. Address block localization based on graph theory

    NASA Astrophysics Data System (ADS)

    Gaceb, Djamel; Eglin, Véronique; Lebourgeois, Frank; Emptoz, Hubert

    2008-01-01

    An efficient mail sorting system is mainly based on an accurate optical recognition of the addresses on the envelopes. However, the localizing of the address block (ABL) should be done before the OCR recognition process. The location step is very crucial as it has a great impact on the global performance of the system. Currently, a good localizing step leads to a better recognition rate. The limit of current methods is mainly caused by modular linear architectures used for ABL: their performances greatly depend on each independent module performance. We are presenting in this paper a new approach for ABL based on a pyramidal data organization and on a hierarchical graph coloring for classification process. This new approach presents the advantage to guarantee a good coherence between different modules and reduces both the computation time and the rejection rate. The proposed method gives a very satisfying rate of 98% of good locations on a set of 750 envelope images.

  10. Optically addressed asymmetric Fabry-Perot modulator

    NASA Technical Reports Server (NTRS)

    Larsson, A.; Maserjian, J.

    1991-01-01

    A low power, high contrast optically addressed modulator, operating with normal incidence, has been fabricated. Optically controlled reflection modulation is achieved through optically induced absorption modulation in a periodically delta-doped InGaAs/GaAs multiple quantum well structure inserted in an integrated asymmetric Fabry-Perot resonator. A contrast ratio over 60:1 was measured using a spectrally matched low power InGaAs/GaAs quantum well laser to generate the write (control) signal. The insertion loss for the normally off modulator is 4.6 dB at the highest write signal power (30 mW) used. The device lends itself to the fabrication of arrays for optically addressed spatial light modulation.

  11. Addressing Medical Errors in Hand Surgery

    PubMed Central

    Johnson, Shepard P.; Adkinson, Joshua M.; Chung, Kevin C.

    2014-01-01

    Influential think-tank such as the Institute of Medicine has raised awareness about the implications of medical errors. In response, organizations, medical societies, and institutions have initiated programs to decrease the incidence and effects of these errors. Surgeons deal with the direct implications of adverse events involving patients. In addition to managing the physical consequences, they are confronted with ethical and social issues when caring for a harmed patient. Although there is considerable effort to implement system-wide changes, there is little guidance for hand surgeons on how to address medical errors. Admitting an error is difficult, but a transparent environment where patients are notified of errors and offered consolation and compensation is essential to maintain trust. Further, equipping hand surgeons with a guide for addressing medical errors will promote compassionate patient interaction, help identify system failures, provide learning points for safety improvement, and demonstrate a commitment to ethically responsible medical care. PMID:25154576

  12. Matrix-addressable electrochromic display cell

    NASA Astrophysics Data System (ADS)

    Beni, G.; Schiavone, L. M.

    1981-04-01

    We report an electrochromic display cell with intrinsic matrix addressability. The cell, based on a sputtered iridium oxide film (SIROF) and a tantalum-oxide hysteretic counterelectrode, has electrochromic parameters (i.e., response times, operating voltages, and contrast) similar to those of other SIROF display devices, but in addition, has short-circuit memory and voltage threshold. Memory and threshold are sufficiently large to allow, in principle, multiplexing of electrochromic display panels of large-screen TV pixel size.

  13. Addressing the United States Debt and Deficit

    DTIC Science & Technology

    2010-03-01

    effectively with the American debt and deficit, by first describing the background of our current government approach to the economy , then examining the...to address the problem of deficit financing and the associated debt in a positive manner and thereby strengthen the economy of the United States...current government approach to the economy , then examining the current projections for United States’ spending from 2009 through 2019 and examining what

  14. Increasing hope by addressing clients' outcome expectations.

    PubMed

    Swift, Joshua K; Derthick, Annie O

    2013-09-01

    Addressing clients' outcome expectations is an important clinical process that can lead to a strong therapeutic alliance, more positive treatment outcomes, and decreased rates of premature termination from psychotherapy. Five interventions designed to foster appropriate outcome expectations are discussed, including presenting a convincing treatment rationale, increasing clients' faith in their therapists, expressing faith in clients, providing outcome education, and comparing progress with expectations. Clinical examples and research support are provided for each.

  15. Aboriginal health promotion through addressing employment discrimination.

    PubMed

    Ferdinand, Angeline S; Paradies, Yin; Perry, Ryan; Kelaher, Margaret

    2014-01-01

    The Localities Embracing and Accepting Diversity (LEAD) program aimed to improve the mental health of Aboriginal Victorians by addressing racial discrimination and facilitating social and economic participation. As part of LEAD, Whittlesea Council adopted the Aboriginal Employment Pathways Strategy (AEPS) to increase Aboriginal employment and retention within the organisation. The Aboriginal Cultural Awareness Training Program was developed to build internal cultural competency and skills in recruiting and retaining Aboriginal staff. Analysis of surveys conducted before (pre; n=124) and after (post; n=107) the training program indicated a significant increase in participant understanding across all program objectives and in support of organisational policies to improve Aboriginal recruitment and retention. Participants ended the training with concrete ideas about intended changes, as well as how these changes could be supported by their supervisors and the wider organisation. Significant resources have since been allocated to implementing the AEPS over 5 years. In line with principles underpinning the National Aboriginal and Torres Strait Islander Health Plan 2013-23, particularly the focus on addressing racism as a determinant of health, this paper explores the AEPS and training program as promising approaches to health promotion through addressing barriers to Aboriginal employment. Possible implications for other large organisations are also considered.

  16. Innovative Legal Approaches to Address Obesity

    PubMed Central

    Pomeranz, Jennifer L; Teret, Stephen P; Sugarman, Stephen D; Rutkow, Lainie; Brownell, Kelly D

    2009-01-01

    Context: The law is a powerful public health tool with considerable potential to address the obesity issue. Scientific advances, gaps in the current regulatory environment, and new ways of conceptualizing rights and responsibilities offer a foundation for legal innovation. Methods: This article connects developments in public health and nutrition with legal advances to define promising avenues for preventing obesity through the application of the law. Findings: Two sets of approaches are defined: (1) direct application of the law to factors known to contribute to obesity and (2) original and innovative legal solutions that address the weak regulatory stance of government and the ineffectiveness of existing policies used to control obesity. Specific legal strategies are discussed for limiting children's food marketing, confronting the potential addictive properties of food, compelling industry speech, increasing government speech, regulating conduct, using tort litigation, applying nuisance law as a litigation strategy, and considering performance-based regulation as an alternative to typical regulatory actions. Finally, preemption is an overriding issue and can play both a facilitative and a hindering role in obesity policy. Conclusions: Legal solutions are immediately available to the government to address obesity and should be considered at the federal, state, and local levels. New and innovative legal solutions represent opportunities to take the law in creative directions and to link legal, nutrition, and public health communities in constructive ways. PMID:19298420

  17. Global-Address Space Networking (GASNet) Library

    SciTech Connect

    Welcome, Michael L.; Bell, Christian S.

    2011-04-06

    GASNet (Global-Address Space Networking) is a language-independent, low-level networking layer that provides network-independent, high-performance communication primitives tailored for implementing parallel global address space SPMD languages such as UPC and Titanium. The interface is primarily intended as a compilation target and for use by runtime library writers (as opposed to end users), and the primary goals are high performance, interface portability, and expressiveness. GASNet is designed specifically to support high-performance, portable implementations of global address space languages on modern high-end communication networks. The interface provides the flexibility and extensibility required to express a wide variety of communication patterns without sacrificing performance by imposing large computational overheads in the interface. The design of the GASNet interface is partitioned into two layers to maximize porting ease without sacrificing performance: the lower level is a narrow but very general interface called the GASNet core API - the design is basedheavily on Active Messages, and is implemented directly on top of each individual network architecture. The upper level is a wider and more expressive interface called GASNet extended API, which provides high-level operations such as remote memory access and various collective operations. This release implements GASNet over MPI, the Quadrics "elan" API, the Myrinet "GM" API and the "LAPI" interface to the IBM SP switch. A template is provided for adding support for additional network interfaces.

  18. Addressing language barriers to healthcare in India.

    PubMed

    Narayan, Lalit

    2013-01-01

    In spite of a growing recognition of the importance of doctor-patient communication, the issue of language barriers to healthcare has received very little attention in India. The Indian population speaks over 22 major languages with English used as the lingua franca for biomedicine. Large-scale internal migration has meant that health workers are encountering increasing instances of language discordance within clinical settings. Research done predominantly in the West has shown language discordance to significantly affect access to care, cause problems of comprehension and adherence, and decrease the satisfaction and quality of care. Addressing language barriers to healthcare in India requires a stronger political commitment to providing non-discriminatory health services, especially to vulnerable groups such as illiterate migrant workers. Research will have to address three broad areas: the ways in which language barriers affect health and healthcare, the efficacy of interventions to overcome language barriers, and the costs of language barriers and efforts to overcome them. There is a need to address such barriers in health worker education and clinical practice. Proven strategies such as hiring multilingual healthcare workers, providing language training to health providers, employing in situ translators or using telephone interpretation services will have to be evaluated for their appropriateness to the Indian context. Internet-based initiatives, the proliferation of mobile phones and recent advances in machine translation promise to contribute to the solution.

  19. Matching Alternative Addresses: a Semantic Web Approach

    NASA Astrophysics Data System (ADS)

    Ariannamazi, S.; Karimipour, F.; Hakimpour, F.

    2015-12-01

    Rapid development of crowd-sourcing or volunteered geographic information (VGI) provides opportunities for authoritatives that deal with geospatial information. Heterogeneity of multiple data sources and inconsistency of data types is a key characteristics of VGI datasets. The expansion of cities resulted in the growing number of POIs in the OpenStreetMap, a well-known VGI source, which causes the datasets to outdate in short periods of time. These changes made to spatial and aspatial attributes of features such as names and addresses might cause confusion or ambiguity in the processes that require feature's literal information like addressing and geocoding. VGI sources neither will conform specific vocabularies nor will remain in a specific schema for a long period of time. As a result, the integration of VGI sources is crucial and inevitable in order to avoid duplication and the waste of resources. Information integration can be used to match features and qualify different annotation alternatives for disambiguation. This study enhances the search capabilities of geospatial tools with applications able to understand user terminology to pursuit an efficient way for finding desired results. Semantic web is a capable tool for developing technologies that deal with lexical and numerical calculations and estimations. There are a vast amount of literal-spatial data representing the capability of linguistic information in knowledge modeling, but these resources need to be harmonized based on Semantic Web standards. The process of making addresses homogenous generates a helpful tool based on spatial data integration and lexical annotation matching and disambiguating.

  20. The dynamics of rapid fracture: instabilities, nonlinearities and length scales.

    PubMed

    Bouchbinder, Eran; Goldman, Tamar; Fineberg, Jay

    2014-04-01

    The failure of materials and interfaces is mediated by cracks, almost singular dissipative structures that propagate at velocities approaching the speed of sound. Crack initiation and subsequent propagation-the dynamic process of fracture-couples a wide range of time and length scales. Crack dynamics challenge our understanding of the fundamental physics processes that take place in the extreme conditions within the almost singular region where material failure occurs. Here, we first briefly review the classic approach to dynamic fracture, namely linear elastic fracture mechanics (LEFM), and discuss its successes and limitations. We show how, on the one hand, recent experiments performed on straight cracks propagating in soft brittle materials have quantitatively confirmed the predictions of this theory to an unprecedented degree. On the other hand, these experiments show how LEFM breaks down as the singular region at the tip of a crack is approached. This breakdown naturally leads to a new theoretical framework coined 'weakly nonlinear fracture mechanics', where weak elastic nonlinearities are incorporated. The stronger singularity predicted by this theory gives rise to a new and intrinsic length scale, ℓnl. These predictions are verified in detail through direct measurements. We then theoretically and experimentally review how the emergence of ℓnl is linked to a new equation for crack motion, which predicts the existence of a high-speed oscillatory crack instability whose wavelength is determined by ℓnl. We conclude by delineating outstanding challenges in the field.

  1. Nonlinear scattering in plasmonic nanostructures

    NASA Astrophysics Data System (ADS)

    Chu, Shi-Wei

    2016-09-01

    Nonlinear phenomena provide novel light manipulation capabilities and innovative applications. Recently, we discovered nonlinear saturation on single-particle scattering of gold nanospheres by continuous-wave laser excitation and innovatively applied to improve microscopic resolution down to λ/8. However, the nonlinearity was limited to the green-orange plasmonic band of gold nanosphere, and the underlying mechanism has not yet been fully understood. In this work, we demonstrated that nonlinear scattering exists for various material/geometry combinations, thus expanding the applicable wavelength range. For near-infrared, gold nanorod is used, while for blue-violet, silver nanospheres are adopted. In terms of mechanism, the nonlinearity may originate from interband/intraband absorption, hot electron, or hot lattice, which are spectrally mixed in the case of gold nanosphere. For gold nanorod and silver nanosphere, nonlinear scattering occurs at plasmonic resonances, which are spectrally far from interband/intraband absorptions, so they are excluded. We found that the nonlinear index is much larger than possible contributions from hot electrons in literature. Therefore, we conclude that hot lattice is the major mechanism. In addition, we propose that similar to z-scan, which is the standard method to characterize nonlinearity of a thin sample, laser scanning microscopy should be adopted as the standard method to characterize nonlinearity from a nanostructure. Our work not only provides the physical mechanism of the nonlinear scattering, but also paves the way toward multi-color superresolution imaging based on non-bleaching plasmonic scattering.

  2. On the possibility of nonlinear quantum evolution and superluminal communication

    NASA Astrophysics Data System (ADS)

    Gao, Shan

    2014-09-01

    A possible mechanism of nonlinear quantum evolution is introduced and its implications for quantum communication are investigated. First, it is argued that an appropriate combination of wavefunction collapse and the consciousness of observer may permit the observer to distinguish nonorthogonal quantum states in principle, and thus consciousness will introduce certain nonlinearity into quantum dynamics. Next, it is shown that the distinguishability of nonorthogonal states can be used to achieve quantum superluminal communication, by which information can be transmitted nonlocally and faster than the speed of light. Finally, the issue of apparent incompatibility between superluminal communication and special relativity is briefly addressed.

  3. Nonlinear acoustics in higher-order approximation: Comment.

    PubMed

    Mitri, Farid G

    2010-08-01

    Some useful expressions for the second- and third-order equations for harmonic generation of infinite plane acoustic waves in a nonlinear non-viscous fluid are corrected. The concern addressed in the present comment is to point out some typographical errors in the first-order velocity and pressure expressions intervening in the calculation of the secondorder nonlinear equations, as well as a miscalculation of the axial component of the third-order Lighthill tensor term and the resulting third-order velocity and pressure equations presented in that paper.

  4. Linear and nonlinear subspace analysis of hand movements during grasping.

    PubMed

    Cui, Phil Hengjun; Visell, Yon

    2014-01-01

    This study investigated nonlinear patterns of coordination, or synergies, underlying whole-hand grasping kinematics. Prior research has shed considerable light on roles played by such coordinated degrees-of-freedom (DOF), illuminating how motor control is facilitated by structural and functional specializations in the brain, peripheral nervous system, and musculoskeletal system. However, existing analyses suppose that the patterns of coordination can be captured by means of linear analyses, as linear combinations of nominally independent DOF. In contrast, hand kinematics is itself highly nonlinear in nature. To address this discrepancy, we sought to to determine whether nonlinear synergies might serve to more accurately and efficiently explain human grasping kinematics than is possible with linear analyses. We analyzed motion capture data acquired from the hands of individuals as they grasped an array of common objects, using four of the most widely used linear and nonlinear dimensionality reduction algorithms. We compared the results using a recently developed algorithm-agnostic quality measure, which enabled us to assess the quality of the dimensional reductions that resulted by assessing the extent to which local neighborhood information in the data was preserved. Although qualitative inspection of this data suggested that nonlinear correlations between kinematic variables were present, we found that linear modeling, in the form of Principle Components Analysis, could perform better than any of the nonlinear techniques we applied.

  5. Subspace-based identification of a nonlinear spacecraft in the time and frequency domains

    NASA Astrophysics Data System (ADS)

    Noël, J. P.; Marchesiello, S.; Kerschen, G.

    2014-02-01

    The objective of the present paper is to address the identification of a strongly nonlinear satellite structure. To this end, two nonlinear subspace identification methods formulated in the time and frequency domains are exploited, referred to as the TNSI and FNSI methods, respectively. The modal parameters of the underlying linear structure and the coefficients of the nonlinearities will be estimated by these two approaches based on periodic random measurements. Their respective merits will also be discussed in terms of both accuracy and computational efficiency and the use of stabilisation diagrams in nonlinear system identification will be introduced. The application of interest is the SmallSat spacecraft developed by EADS-Astrium, which possesses an impact-type nonlinear device consisting of eight mechanical stops limiting the motion of an inertia wheel mounted on an elastomeric interface. This application is challenging for several reasons including the non-smooth nature of the nonlinearities, high modal density and high non-proportional damping.

  6. Frequency domain nonlinear optics

    NASA Astrophysics Data System (ADS)

    Legare, Francois

    2016-05-01

    The universal dilemma of gain narrowing occurring in fs amplifiers prevents ultra-high power lasers from delivering few-cycle pulses. This problem is overcome by a new amplification concept: Frequency domain Optical Parametric Amplification - FOPA. It enables simultaneous up-scaling of peak power and amplified spectral bandwidth and can be performed at any wavelength range of conventional amplification schemes, however, with the capability to amplify single cycles of light. The key idea for amplification of octave-spanning spectra without loss of spectral bandwidth is to amplify the broad spectrum ``slice by slice'' in the frequency domain, i.e. in the Fourier plane of a 4f-setup. The striking advantages of this scheme, are its capability to amplify (more than) one octave of bandwidth without shorting the corresponding pulse duration. This is because ultrabroadband phase matching is not defined by the properties of the nonlinear crystal employed but the number of crystals employed. In the same manner, to increase the output energy one simply has to increase the spectral extension in the Fourier plane and to add one more crystal. Thus, increasing pulse energy and shortening its duration accompany each other. A proof of principle experiment was carried out at ALLS on the sub-two cycle IR beam line and yielded record breaking performance in the field of few-cycle IR lasers. 100 μJ two-cycle pulses from a hollow core fibre compression setup were amplified to 1.43mJ without distorting spatial or temporal properties. Pulse duration at the input of FOPA and after FOPA remains the same. Recently, we have started upgrading this system to be pumped by 250 mJ to reach 40 mJ two-cycle IR few-cycle pulses and latest results will be presented at the conference. Furthermore, the extension of the concept of FOPA to other nonlinear optical processes will be discussed. Frequency domain nonlinear optics.

  7. Addressing Risks to Advance Mental Health Research

    PubMed Central

    Iltis, Ana S.; Misra, Sahana; Dunn, Laura B.; Brown, Gregory K.; Campbell, Amy; Earll, Sarah A.; Glowinski, Anne; Hadley, Whitney B.; Pies, Ronald; DuBois, James M.

    2015-01-01

    Objective Risk communication and management are essential to the ethical conduct of research, yet addressing risks may be time consuming for investigators and institutional review boards (IRBs) may reject study designs that appear too risky. This can discourage needed research, particularly in higher risk protocols or those enrolling potentially vulnerable individuals, such as those with some level of suicidality. Improved mechanisms for addressing research risks may facilitate much needed psychiatric research. This article provides mental health researchers with practical approaches to: 1) identify and define various intrinsic research risks; 2) communicate these risks to others (e.g., potential participants, regulatory bodies, society); 3) manage these risks during the course of a study; and 4) justify the risks. Methods As part of a National Institute of Mental Health (NIMH)-funded scientific meeting series, a public conference and a closed-session expert panel meeting were held on managing and disclosing risks in mental health clinical trials. The expert panel reviewed the literature with a focus on empirical studies and developed recommendations for best practices and further research on managing and disclosing risks in mental health clinical trials. IRB review was not required because there were no human subjects. The NIMH played no role in developing or reviewing the manuscript. Results Challenges, current data, practical strategies, and topics for future research are addressed for each of four key areas pertaining to management and disclosure of risks in clinical trials: identifying and defining risks, communicating risks, managing risks during studies, and justifying research risks. Conclusions Empirical data on risk communication, managing risks, and the benefits of research can support the ethical conduct of mental health research and may help investigators better conceptualize and confront risks and to gain IRB approval. PMID:24173618

  8. Linearization of Nonlinear Systems.

    DTIC Science & Technology

    1986-11-24

    series. IEEE Trans. Circuits Syst., CAS-32(11):1150-1171, November 1985. [BC85b] S. Boyd and L. 0. Chua. Uniqueness of circuits and systems containing...Control and Information Sciences vol. 58, p10 1- 1 19 , June 1983. [BC85c] S. Boyd and L. 0. Chua. Volterra series for nonlinear circuits . In Proc. IEEE...ISCAS, Tokyo, June 1985. [BCD84] S. Boyd, L. 0. Chua, and C. A. Desoer . Analytical foundations of Volterra series. IMA Journal of Mathematical

  9. Nonlinear backreaction in cosmology

    NASA Astrophysics Data System (ADS)

    Green, Stephen Roland

    This thesis, based on two papers by Green and Wald, investigates the problem of nonlinear backreaction in cosmology. We first analyze the problem in a general context by developing a new, mathematically precise framework for treating the effects of nonlinear phenomena occurring on small scales in general relativity. Our framework requires the metric to be close to a background metric (not necessarily a cosmological metric), but allows arbitrarily large stress-energy fluctuations on small scales. We prove that, within our framework, if the matter stress-energy tensor satisfies the weak energy condition (i.e., positivity of energy density in all frames), then the only effect that small-scale inhomogeneities can have on the background metric is to provide an effective stress-energy tensor that is traceless and satisfies the weak energy condition itself—corresponding to the presence of gravitational radiation. In particular, nonlinear effects produced by small-scale inhomogeneities cannot mimic the effects of dark energy. We also develop perturbation theory off of the background metric. We derive an equation for the long-wavelength part of the leading order deviation of the metric from the background metric, which contains the usual terms occurring in linearized perturbation theory plus additional contributions from the small-scale inhomogeneities. Next, we apply our framework to the cosmological context, specializing our background metric to be of the Friedmann-Lemaitre-Robertson-Walker form. We demonstrate that, in the case of dust matter, a cosmological constant, and vanishing spatial curvature (i.e., our universe today), Newtonian gravity alone provides a good global description of an inhomogeneous general relativistic cosmology, even when there is significant nonlinear dynamical behavior at small scales. Namely, we find a relatively straightforward dictionary—which is exact at the linearized level—that maps Newtonian dust cosmologies into

  10. Building technology services that address student needs.

    PubMed

    Le Ber, Jeanne M; Lombardo, Nancy T; Wimmer, Erin

    2015-01-01

    A 16-question technology use survey was conducted to assess incoming health sciences students' knowledge of and interest in current technologies, and to identify student device and tool preferences. Survey questions were developed by colleagues at a peer institution and then edited to match this library's student population. Two years of student responses have been compiled, compared, and reviewed as a means for informing library decisions related to technology and resource purchases. Instruction and event programming have been revised to meet student preferences. Based on the number of students using Apple products, librarians are addressing the need to become more proficient with this platform.

  11. Optical addressing technique for a CMOS RAM

    NASA Technical Reports Server (NTRS)

    Wu, W. H.; Bergman, L. A.; Allen, R. A.; Johnston, A. R.

    1988-01-01

    Progress on optically addressing a CMOS RAM for a feasibility demonstration of free space optical interconnection is reported in this paper. The optical RAM chip has been fabricated and functional testing is in progress. Initial results seem promising. New design and SPICE simulation of optical gate cell (OGC) circuits have been carried out to correct the slow fall time of the 'weak pull down' OGC, which has been characterized experimentally. Methods of reducing the response times of the photodiodes and the associated circuits are discussed. Even with the current photodiode, it appears that an OGC can be designed with a performance that is compatible with a CMOS circuit such as the RAM.

  12. Addressing tomorrow's DMO technical challenges today

    NASA Astrophysics Data System (ADS)

    Milligan, James R.

    2009-05-01

    Distributed Mission Operations (DMO) is essentially a type of networked training that pulls in participants from all the armed services and, increasingly, allies to permit them to "game" and rehearse highly complex campaigns, using a mix of local, distant, and virtual players. The United States Air Force Research Laboratory (AFRL) is pursuing Science and Technology (S&T) solutions to address technical challenges associated with distributed communications and information management as DMO continues to progressively scale up the number, diversity, and geographic dispersal of participants in training and rehearsal exercises.

  13. Addressing the water budget with SMOS

    NASA Astrophysics Data System (ADS)

    Kerr, Y. H.; AlBitar, A.; Tomer, S. K.; Merlin, O.; Pellarin, T.

    2012-12-01

    SMOS, a L Band radiometer using aperture synthesis to achieve a good spatial resolution, was successfully launched on November 2, 2009. It was developed and made under the leadership of the European Space Agency (ESA) as an Earth Explorer Opportunity mission. It is a joint program with the Centre National d'Etudes Spatiales (CNES) in France and the Centro para el Desarrollo Teccnologico Industrial (CDTI) in Spain. SMOS carries a single payload, an L band 2D interferometric,radiometer in the 1400-1427 MHz h protected band. This wavelength penetrates well through the vegetation and the atmosphere is almost transparent enabling to infer both soil moisture and vegetation water content. SMOS achieves an unprecedented spatial resolution of 50 km at L-band maximum (43 km on average) with multi angular-dual polarized (or fully polarized) brightness temperatures over the globe and with a revisit time smaller than 3 days. SMOS as been now acquiring data for almost 2 years. The data quality exceeds what was expected, showing very good sensitivity and stability. The data is however very much impaired by man made emission in the protected band, leading to degraded measurements in several areas including parts of Europe and of China. However, many different international teams are now addressing cal val activities in various parts of the world, with notably large field campaigns either on the long time scale or over specific targets to address the specific issues. In parallel different teams are now starting addressing data use in various fields including hydrology. It requires coupling with other models and or disaggregation to address soil moisture distribution over watersheds. Significant new results were obtained for floods and drought events, together with new potential applications in terms of precipitation monitoring This paper thus gives an overview of the science goals of the SMOS mission, a description of its main elements, and a taste of the first results including

  14. Addressing the underperformance of faculty and staff.

    PubMed

    Kenner, Carole; Pressler, Jana L

    2006-01-01

    Many new nursing leaders assuming work as deans, assistant deans, or interim deans have limited education, experience, or background to prepare them for the job. To assist new deans and those aspiring to be deans, the authors of this department, both deans, offer survival tips based on their personal experiences and insights. They address common issues, challenges, and opportunities that face academic executive teams, such as negotiating an executive contract, obtaining faculty lines, building effective work teams, managing difficult employees, and creating nimble organizational structure to respond to changing consumer, healthcare delivery, and community needs. The authors welcome counterpoint discussions with readers.

  15. A Task Force to Address Bullying.

    PubMed

    Keller, Ronald; Budin, Wendy C; Allie, Tammy

    2016-02-01

    Bullying in the workplace can create a dysfunctional environment that is associated with serious physical and psychological harm to the person being bullied. Nurses' experience with bullying has gained considerable attention in recent years, and warrants further discussion. Nurse leaders need to develop and implement effective bullying prevention initiatives that will foster the functioning of a professional and productive staff in a healthy work environment. The aim of this article is to review workplace bullying as experienced by nurses, and describe how nurses at a Magnet-designated academic medical center developed and implemented a bullying task force to address the problem.

  16. Finite elements of nonlinear continua.

    NASA Technical Reports Server (NTRS)

    Oden, J. T.

    1972-01-01

    The finite element method is extended to a broad class of practical nonlinear problems, treating both theory and applications from a general and unifying point of view. The thermomechanical principles of continuous media and the properties of the finite element method are outlined, and are brought together to produce discrete physical models of nonlinear continua. The mathematical properties of the models are analyzed, and the numerical solution of the equations governing the discrete models is examined. The application of the models to nonlinear problems in finite elasticity, viscoelasticity, heat conduction, and thermoviscoelasticity is discussed. Other specific topics include the topological properties of finite element models, applications to linear and nonlinear boundary value problems, convergence, continuum thermodynamics, finite elasticity, solutions to nonlinear partial differential equations, and discrete models of the nonlinear thermomechanical behavior of dissipative media.

  17. Nonlinear Ultrasonic Phased Array Imaging

    NASA Astrophysics Data System (ADS)

    Potter, J. N.; Croxford, A. J.; Wilcox, P. D.

    2014-10-01

    This Letter reports a technique for the imaging of acoustic nonlinearity. By contrasting the energy of the diffuse field produced through the focusing of an ultrasonic array by delayed parallel element transmission with that produced by postprocessing of sequential transmission data, acoustic nonlinearity local to the focal point is measured. Spatially isolated wave distortion is inferred without requiring interrogation of the wave at the inspection point, thereby allowing nonlinear imaging through depth.

  18. Nonlinear ultrasonic phased array imaging.

    PubMed

    Potter, J N; Croxford, A J; Wilcox, P D

    2014-10-03

    This Letter reports a technique for the imaging of acoustic nonlinearity. By contrasting the energy of the diffuse field produced through the focusing of an ultrasonic array by delayed parallel element transmission with that produced by postprocessing of sequential transmission data, acoustic nonlinearity local to the focal point is measured. Spatially isolated wave distortion is inferred without requiring interrogation of the wave at the inspection point, thereby allowing nonlinear imaging through depth.

  19. Implementation of Outstanding Electronic Transport in Polar Covalent Boron Nitride Atomic Chains: another Extraordinary Odd-Even Behaviour

    PubMed Central

    Xu, Xiaodong; Li, Weiqi; Liu, Linhua; Feng, Jikang; Jiang, Yongyuan; Tian, Wei Quan

    2016-01-01

    A theoretical investigation of the unique electronic transport properties of the junctions composed of boron nitride atomic chains bridging symmetric graphene electrodes with point-contacts is executed through non-equilibrium Green’s function technique in combination with density functional theory. Compared with carbon atomic chains, the boron nitride atomic chains have an alternative arrangement of polar covalent B-N bonds and different contacts coupling electrodes, showing some unusual properties in functional atomic electronic devices. Remarkably, they have an extraordinary odd-even behavior of conductivity with the length increase. The rectification character and negative differential resistance of nonlinear current-voltage characteristics can be achieved by manipulating the type of contacts between boron nitride atomic chains bridges and electrodes. The junctions with asymmetric contacts have an intrinsic rectification, caused by stronger coupling in the C-N contact than the C-B contact. On the other hand, for symmetric contact junctions, it is confirmed that the transport properties of the junctions primarily depend on the nature of contacts. The junctions with symmetric C-N contacts have higher conductivity than their C-B contacts counterparts. Furthermore, the negative differential resistances of the junctions with only C-N contacts is very conspicuous and can be achieved at lower bias. PMID:27211110

  20. Implementation of Outstanding Electronic Transport in Polar Covalent Boron Nitride Atomic Chains: another Extraordinary Odd-Even Behaviour.

    PubMed

    Xu, Xiaodong; Li, Weiqi; Liu, Linhua; Feng, Jikang; Jiang, Yongyuan; Tian, Wei Quan

    2016-05-23

    A theoretical investigation of the unique electronic transport properties of the junctions composed of boron nitride atomic chains bridging symmetric graphene electrodes with point-contacts is executed through non-equilibrium Green's function technique in combination with density functional theory. Compared with carbon atomic chains, the boron nitride atomic chains have an alternative arrangement of polar covalent B-N bonds and different contacts coupling electrodes, showing some unusual properties in functional atomic electronic devices. Remarkably, they have an extraordinary odd-even behavior of conductivity with the length increase. The rectification character and negative differential resistance of nonlinear current-voltage characteristics can be achieved by manipulating the type of contacts between boron nitride atomic chains bridges and electrodes. The junctions with asymmetric contacts have an intrinsic rectification, caused by stronger coupling in the C-N contact than the C-B contact. On the other hand, for symmetric contact junctions, it is confirmed that the transport properties of the junctions primarily depend on the nature of contacts. The junctions with symmetric C-N contacts have higher conductivity than their C-B contacts counterparts. Furthermore, the negative differential resistances of the junctions with only C-N contacts is very conspicuous and can be achieved at lower bias.

  1. Multi-port, optically addressed RAM

    NASA Technical Reports Server (NTRS)

    Johnston, Alan R. (Inventor); Nixon, Robert H. (Inventor); Bergman, Larry A. (Inventor); Esener, Sadik (Inventor)

    1989-01-01

    A random access memory addressing system utilizing optical links between memory and the read/write logic circuits comprises addressing circuits including a plurality of light signal sources, a plurality of optical gates including optical detectors associated with the memory cells, and a holographic optical element adapted to reflect and direct the light signals to the desired memory cell locations. More particularly, it is a multi-port, binary computer memory for interfacing with a plurality of computers. There are a plurality of storage cells for containing bits of binary information, the storage cells being disposed at the intersections of a plurality of row conductors and a plurality of column conductors. There is interfacing logic for receiving information from the computers directing access to ones of the storage cells. There are first light sources associated with the interfacing logic for transmitting a first light beam with the access information modulated thereon. First light detectors are associated with the storage cells for receiving the first light beam, for generating an electrical signal containing the access information, and for conducting the electrical signal to the one of the storage cells to which it is directed. There are holographic optical elements for reflecting the first light beam from the first light sources to the first light detectors.

  2. Addressing Science Use Cases with HELIO

    NASA Astrophysics Data System (ADS)

    Bentley, R. D.; Aboudarham, J.; Csillaghy, A.; Jacquey, C.; Hapgood, M. A.; Messerotti, M.; Gallagher, P.; Bocchialini, K.; Hurlburt, N. E.; Roberts, D.; Sanchez Duarte, L.

    2009-12-01

    The Heliophysics Integrated Observatory (HELIO) is a new VO project funded under the EC's Seventh Framework Programme (FP7). It includes thirteen partners scattered over six countries and is led by University College London. HELIO is designed to support the heliophysics community and is based on a Service Oriented Architecture. The services developed by and integrated into HELIO can be used to address a wide range of science problems; they can be used individually or as part of a work-flow driven search engine that can use a propagation (or other) model to help locate obervations that describe interesting phenomena. We will describe and discuss how the components of HELIO could be used to address science use cases, particularly how a user can adapt the work flow to their own science interests. Networking is one of the three Activities of the HELIO Integrated Infrastructure Initiatives (I3) project. Within this activity we plan to involve the community in all aspects of the design and testing of the HELIO system, including determining which data and metadata should be included, how the quality and content of metadata can be included, etc. We are investigating ways of making HELIO "domain-aware" so that researchers who are specialists in one of the communities that constitute heliophysics can easily identify, access and use data they need from the other communities. We will discuss how the community can help us develop this capability.

  3. Addressing Asthma Health Disparities: A Multilevel Challenge

    PubMed Central

    Canino, Glorisa; McQuaid, Elizabeth L.; Rand, Cynthia S.

    2009-01-01

    Substantial research has documented pervasive disparities in the prevalence, severity, and morbidity of asthma among minority populations compared to non-Latino whites. The underlying causes of these disparities are not well understood, and as a result, the leverage points to address them remain unclear. A multilevel framework for integrating research in asthma health disparities is proposed in order to advance both future research and clinical practice. The components of the proposed model include health care policies and regulations, operation of the health care system, provider/clinician-level factors, social/environmental factors, and individual/family attitudes and behaviors. The body of research suggests that asthma disparities have multiple, complex and inter-related sources. Disparities occur when individual, environmental, health system, and provider factors interact with one another over time. Given that the causes of asthma disparities are complex and multilevel, clinical strategies to address these disparities must therefore be comparably multilevel and target many aspects of asthma care. Clinical Implications: Several strategies that could be applied in clinical settings to reduce asthma disparities are described including the need for routine assessment of the patient’s beliefs, financial barriers to disease management, and health literacy, and the provision of cultural competence training and communication skills to health care provider groups. PMID:19447484

  4. Problems in nonlinear resistive MHD

    SciTech Connect

    Turnbull, A.D.; Strait, E.J.; La Haye, R.J.; Chu, M.S.; Miller, R.L.

    1998-12-31

    Two experimentally relevant problems can relatively easily be tackled by nonlinear MHD codes. Both problems require plasma rotation in addition to the nonlinear mode coupling and full geometry already incorporated into the codes, but no additional physics seems to be crucial. These problems discussed here are: (1) nonlinear coupling and interaction of multiple MHD modes near the B limit and (2) nonlinear coupling of the m/n = 1/1 sawtooth mode with higher n gongs and development of seed islands outside q = 1.

  5. Nonlinear Peltier effect in semiconductors

    NASA Astrophysics Data System (ADS)

    Zebarjadi, Mona; Esfarjani, Keivan; Shakouri, Ali

    2007-09-01

    Nonlinear Peltier coefficient of a doped InGaAs semiconductor is calculated numerically using the Monte Carlo technique. The Peltier coefficient is also obtained analytically for single parabolic band semiconductors assuming a shifted Fermi-Dirac electronic distribution under an applied bias. Analytical results are in agreement with numerical simulations. Key material parameters affecting the nonlinear behavior are doping concentration, effective mass, and electron-phonon coupling. Current density thresholds at which nonlinear behavior is observable are extracted from numerical data. It is shown that the nonlinear Peltier effect can be used to enhance cooling of thin film microrefrigerator devices especially at low temperatures.

  6. Nonlinear Attitude Filtering Methods

    NASA Technical Reports Server (NTRS)

    Markley, F. Landis; Crassidis, John L.; Cheng, Yang

    2005-01-01

    This paper provides a survey of modern nonlinear filtering methods for attitude estimation. Early applications relied mostly on the extended Kalman filter for attitude estimation. Since these applications, several new approaches have been developed that have proven to be superior to the extended Kalman filter. Several of these approaches maintain the basic structure of the extended Kalman filter, but employ various modifications in order to provide better convergence or improve other performance characteristics. Examples of such approaches include: filter QUEST, extended QUEST, the super-iterated extended Kalman filter, the interlaced extended Kalman filter, and the second-order Kalman filter. Filters that propagate and update a discrete set of sigma points rather than using linearized equations for the mean and covariance are also reviewed. A two-step approach is discussed with a first-step state that linearizes the measurement model and an iterative second step to recover the desired attitude states. These approaches are all based on the Gaussian assumption that the probability density function is adequately specified by its mean and covariance. Other approaches that do not require this assumption are reviewed, including particle filters and a Bayesian filter based on a non-Gaussian, finite-parameter probability density function on SO(3). Finally, the predictive filter, nonlinear observers and adaptive approaches are shown. The strengths and weaknesses of the various approaches are discussed.

  7. NONLINEAR ATOM OPTICS

    SciTech Connect

    T. MILONNI; G. CSANAK; ET AL

    1999-07-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The project objectives were to explore theoretically various aspects of nonlinear atom optics effects in cold-atom waves and traps. During the project a major development occurred the observation, by as many as a dozen experimental groups, of Bose-Einstein condensation (BEC) in cold-atom traps. This stimulated us to focus our attention on those aspects of nonlinear atom optics relating to BEC, in addition to continuing our work on a nonequilibrium formalism for dealing with the interaction of an electromagnetic field with multi-level atomic systems, allowing for macroscopic coherence effects such as BEC. Studies of several problems in BEC physics have been completed or are near completion, including the suggested use of external electric fields to modify the nature of the interatomic interaction in cold-atom traps; properties of two-phase condensates; and molecular loss processes associated with BEC experiments involving a so-called Feshbach resonance.

  8. Nonlinear material behaviour of spider silk yields robust webs.

    PubMed

    Cranford, Steven W; Tarakanova, Anna; Pugno, Nicola M; Buehler, Markus J

    2012-02-01

    Natural materials are renowned for exquisite designs that optimize function, as illustrated by the elasticity of blood vessels, the toughness of bone and the protection offered by nacre. Particularly intriguing are spider silks, with studies having explored properties ranging from their protein sequence to the geometry of a web. This material system, highly adapted to meet a spider's many needs, has superior mechanical properties. In spite of much research into the molecular design underpinning the outstanding performance of silk fibres, and into the mechanical characteristics of web-like structures, it remains unknown how the mechanical characteristics of spider silk contribute to the integrity and performance of a spider web. Here we report web deformation experiments and simulations that identify the nonlinear response of silk threads to stress--involving softening at a yield point and substantial stiffening at large strain until failure--as being crucial to localize load-induced deformation and resulting in mechanically robust spider webs. Control simulations confirmed that a nonlinear stress response results in superior resistance to structural defects in the web compared to linear elastic or elastic-plastic (softening) material behaviour. We also show that under distributed loads, such as those exerted by wind, the stiff behaviour of silk under small deformation, before the yield point, is essential in maintaining the web's structural integrity. The superior performance of silk in webs is therefore not due merely to its exceptional ultimate strength and strain, but arises from the nonlinear response of silk threads to strain and their geometrical arrangement in a web.

  9. Modified impulse method for the measurement of the frequency response of acoustic filters to weakly nonlinear transient excitations

    PubMed

    Payri; Desantes; Broatch

    2000-02-01

    In this paper, a modified impulse method is proposed which allows the determination of the influence of the excitation characteristics on acoustic filter performance. Issues related to nonlinear propagation, namely wave steepening and wave interactions, have been addressed in an approximate way, validated against one-dimensional unsteady nonlinear flow calculations. The results obtained for expansion chambers and extended duct resonators indicate that the amplitude threshold for the onset of nonlinear phenomena is related to the geometry considered.

  10. Addressing submarine geohazards through scientific drilling

    NASA Astrophysics Data System (ADS)

    Camerlenghi, A.

    2009-04-01

    Natural submarine geohazards (earthquakes, volcanic eruptions, landslides, volcanic island flank collapses) are geological phenomena originating at or below the seafloor leading to a situation of risk for off-shore and on-shore structures and the coastal population. Addressing submarine geohazards means understanding their spatial and temporal variability, the pre-conditioning factors, their triggers, and the physical processes that control their evolution. Such scientific endeavour is nowadays considered by a large sector of the international scientific community as an obligation in order to contribute to the mitigation of the potentially destructive societal effects of submarine geohazards. The study of submarine geohazards requires a multi-disciplinary scientific approach: geohazards must be studied through their geological record; active processes must be monitored; geohazard evolution must be modelled. Ultimately, the information must be used for the assessment of vulnerability, risk analysis, and development of mitigation strategies. In contrast with the terrestrial environment, the oceanic environment is rather hostile to widespread and fast application of high-resolution remote sensing techniques, accessibility for visual inspection, sampling and installation of monitoring stations. Scientific Drilling through the IODP (including the related pre site-survey investigations, sampling, logging and in situ measurements capability, and as a platform for deployment of long term observatories at the surface and down-hole) can be viewed as the centre of gravity of an international, coordinated, multi-disciplinary scientific approach to address submarine geohazards. The IODP Initial Science Plan expiring in 2013 does not address openly geohazards among the program scientific objectives. Hazards are referred to mainly in relation to earthquakes and initiatives towards the understanding of seismogenesis. Notably, the only drilling initiative presently under way is the

  11. Addressing health literacy in patient decision aids

    PubMed Central

    2013-01-01

    Background Effective use of a patient decision aid (PtDA) can be affected by the user’s health literacy and the PtDA’s characteristics. Systematic reviews of the relevant literature can guide PtDA developers to attend to the health literacy needs of patients. The reviews reported here aimed to assess: 1. a) the effects of health literacy / numeracy on selected decision-making outcomes, and b) the effects of interventions designed to mitigate the influence of lower health literacy on decision-making outcomes, and 2. the extent to which existing PtDAs a) account for health literacy, and b) are tested in lower health literacy populations. Methods We reviewed literature for evidence relevant to these two aims. When high-quality systematic reviews existed, we summarized their evidence. When reviews were unavailable, we conducted our own systematic reviews. Results Aim 1: In an existing systematic review of PtDA trials, lower health literacy was associated with lower patient health knowledge (14 of 16 eligible studies). Fourteen studies reported practical design strategies to improve knowledge for lower health literacy patients. In our own systematic review, no studies reported on values clarity per se, but in 2 lower health literacy was related to higher decisional uncertainty and regret. Lower health literacy was associated with less desire for involvement in 3 studies, less question-asking in 2, and less patient-centered communication in 4 studies; its effects on other measures of patient involvement were mixed. Only one study assessed the effects of a health literacy intervention on outcomes; it showed that using video to improve the salience of health states reduced decisional uncertainty. Aim 2: In our review of 97 trials, only 3 PtDAs overtly addressed the needs of lower health literacy users. In 90% of trials, user health literacy and readability of the PtDA were not reported. However, increases in knowledge and informed choice were reported in those studies

  12. On MHD nonlinear stretching flow of Powell-Eyring nanomaterial

    NASA Astrophysics Data System (ADS)

    Hayat, Tasawar; Sajjad, Rai; Muhammad, Taseer; Alsaedi, Ahmed; Ellahi, Rahmat

    This communication addresses the magnetohydrodynamic (MHD) flow of Powell-Eyring nanomaterial bounded by a nonlinear stretching sheet. Novel features regarding thermophoresis and Brownian motion are taken into consideration. Powell-Eyring fluid is electrically conducted subject to non-uniform applied magnetic field. Assumptions of small magnetic Reynolds number and boundary layer approximation are employed in the mathematical development. Zero nanoparticles mass flux condition at the sheet is selected. Adequate transformation yield nonlinear ordinary differential systems. The developed nonlinear systems have been computed through the homotopic approach. Effects of different pertinent parameters on velocity, temperature and concentration fields are studied and analyzed. Further numerical data of skin friction and heat transfer rate is also tabulated and interpreted.

  13. Numerical studies of identification in nonlinear distributed parameter systems

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Lo, C. K.; Reich, Simeon; Rosen, I. G.

    1989-01-01

    An abstract approximation framework and convergence theory for the identification of first and second order nonlinear distributed parameter systems developed previously by the authors and reported on in detail elsewhere are summarized and discussed. The theory is based upon results for systems whose dynamics can be described by monotone operators in Hilbert space and an abstract approximation theorem for the resulting nonlinear evolution system. The application of the theory together with numerical evidence demonstrating the feasibility of the general approach are discussed in the context of the identification of a first order quasi-linear parabolic model for one dimensional heat conduction/mass transport and the identification of a nonlinear dissipation mechanism (i.e., damping) in a second order one dimensional wave equation. Computational and implementational considerations, in particular, with regard to supercomputing, are addressed.

  14. How is environmental conflict addressed by SIA?

    SciTech Connect

    Barrow, C.J.

    2010-09-15

    The fields of Environmental Conflict Management (ECM), Environmental Conflict Resolution (ECR), and Peace and Conflict Impact Assessment (PCIA) have become well established; however, as yet there has not been much use of Social Impact Assessment (SIA) to manage environmental conflicts. ECM, ECR and PCIA are mainly undertaken when problems are advanced or, more likely, have run their course (post-conflict). This paper examines how conflict is addressed by SIA and whether there is potential to develop it for more proactive assessment of conflicts (pre-conflict or while things develop). SIA has the potential to identify and clarify the cause(s) of environmental and natural resources conflicts, and could possibly enable some avoidance or early mitigation. A promising approach may be for 'conflict-aware' SIA to watch for critical conflict stages or thresholds and to monitor stakeholders. Effective conflict-aware SIA might also significantly contribute to efforts to achieve sustainable development.

  15. Applying evolutionary biology to address global challenges.

    PubMed

    Carroll, Scott P; Jørgensen, Peter Søgaard; Kinnison, Michael T; Bergstrom, Carl T; Denison, R Ford; Gluckman, Peter; Smith, Thomas B; Strauss, Sharon Y; Tabashnik, Bruce E

    2014-10-17

    Two categories of evolutionary challenges result from escalating human impacts on the planet. The first arises from cancers, pathogens, and pests that evolve too quickly and the second, from the inability of many valued species to adapt quickly enough. Applied evolutionary biology provides a suite of strategies to address these global challenges that threaten human health, food security, and biodiversity. This Review highlights both progress and gaps in genetic, developmental, and environmental manipulations across the life sciences that either target the rate and direction of evolution or reduce the mismatch between organisms and human-altered environments. Increased development and application of these underused tools will be vital in meeting current and future targets for sustainable development.

  16. Professional Culture and Climate: Addressing Unconscious Bias

    NASA Astrophysics Data System (ADS)

    Knezek, Patricia

    2016-10-01

    Unconscious bias reflects expectations or stereotypes that influence our judgments of others (regardless of our own group). Everyone has unconscious biases. The end result of unconscious bias can be an accumulation of advantage or disadvantage that impacts the long term career success of individuals, depending on which biases they are subject to. In order to foster a professional culture and climate, being aware of these unconscious biases and mitigating against them is a first step. This is particularly important when judgements are needed, such as in cases for recruitment, choice of speakers for conferences, and even reviewing papers submitted for publication. This presentation will cover how unconscious bias manifests itself, what evidence exists to demonstrate it exists, and ways it can be addressed.

  17. Applying evolutionary biology to address global challenges

    PubMed Central

    Carroll, Scott P.; Jørgensen, Peter Søgaard; Kinnison, Michael T.; Bergstrom, Carl T.; Denison, R. Ford; Gluckman, Peter; Smith, Thomas B.; Strauss, Sharon Y.; Tabashnik, Bruce E.

    2014-01-01

    Two categories of evolutionary challenges result from escalating human impacts on the planet. The first arises from cancers, pathogens and pests that evolve too quickly, and the second from the inability of many valued species to adapt quickly enough. Applied evolutionary biology provides a suite of strategies to address these global challenges that threaten human health, food security, and biodiversity. This review highlights both progress and gaps in genetic, developmental and environmental manipulations across the life sciences that either target the rate and direction of evolution, or reduce the mismatch between organisms and human-altered environments. Increased development and application of these underused tools will be vital in meeting current and future targets for sustainable development. PMID:25213376

  18. Advancing efforts to address youth violence involvement.

    PubMed

    Weist, M D; Cooley-Quille, M

    2001-06-01

    Discusses the increased public attention on violence-related problems among youth and the concomitant increased diversity in research. Youth violence involvement is a complex construct that includes violence experienced in multiple settings (home, school, neighborhood) and in multiple forms (as victims, witnesses, perpetrators, and through family members, friends, and the media). Potential impacts of such violence involvement are considerable, including increased internalizing and externalizing behaviors among youth and future problems in school adjustment and life-course development. This introductory article reviews key dimensions of youth-related violence, describes an American Psychological Association Task Force (Division 12) developed to advance relevant research, and presents examples of national resources and efforts that attempt to address this critical public health issue.

  19. Presidential address, 2001. Advice to young surgeons.

    PubMed

    MacFarlane, John K

    2002-04-01

    In his 2001 presidential address to the Canadian Association of General Surgeons, the author offers advice to young surgeons, based on his lifetime experience as a surgical educator, researcher and practitioner. He offers the following samples of wisdom for young surgeons: they should be prepared for a lifetime of learning and be willing and able to adapt to new advances; they should listen to their patients as they describe their presenting complaints and not be tempted to interrupt; they should take time in an emergency situation and remember that split-second decisions can affect the patient for a lifetime; they should be willing to take advice from fellow professionals; they should take time to maintain a quality family life and take adequate time away from the workplace; they should be active be a role model in their community; and, finally, they should get involved and adopt an advocacy role in their profession.

  20. Presidential address, 2001. Advice to young surgeons

    PubMed Central

    MacFarlane, John K.

    2002-01-01

    In his 2001 presidential address to the Canadian Association of General Surgeons, the author offers advice to young surgeons, based on his lifetime experience as a surgical educator, researcher and practitioner. He offers the following samples of wisdom for young surgeons: they should be prepared for a lifetime of learning and be willing and able to adapt to new advances; they should listen to their patients as they describe their presenting complaints and not be tempted to interrupt; they should take time in an emergency situation and remember that split-second decisions can affect the patient for a lifetime; they should be willing to take advice from fellow professionals; they should take time to maintain a quality family life and take adequate time away from the workplace; they should be active be a role model in their community; and, finally, they should get involved and adopt an advocacy role in their profession. PMID:11939654