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Sample records for ahlers ucsb kitp

  1. Developing Online Oceanography at UCSB

    NASA Astrophysics Data System (ADS)

    Prothero, W. A.; Dodson, H.

    2001-12-01

    Oceanography at UCSB is an introductory general education science course taken by up to 200 students per quarter. The emphasis is on learning science process by engaging in authentic science activities that use real earth data. Recently, to increase student motivation, the course has been modified to include an Earth Summit framework. The online support being developed for this course is the first step in the creation of a completely online oceanography class. Foundation software was first tested in the class during Spring 2001. Online activities that are supported are writing and instructor feedback, online threaded discussion with live chat and graphics, automatically graded homeworks and games, auto graded quizzes with questions randomly selected from a database, and thought problems graded by the instructor(s). Future plans include integration with commercial course management software. To allow choice of assignments, all course activities totaled110%. Since grades were based on A=90-100, B=80-90, C= 70-80, etc, it was possible to get a better than A grade. Students see the effect (on their grade) of each assignment by calculating their current course grade. Course activities included (most of which are automatically graded): weekly lab homeworks, weekly mini-quizzes (10 multiple choice questions selected at random from a topic database), weekly thought questions (graded by the TA), 3 written assignments, and "Question of the Day" from lecture (credit given for handing it in), The online writing software allowed students to enter their writing, edit and link to graphic images, print the paper, and electronically hand it in. This has the enormous advantage of allowing the instructor and TA's convenient access to all student papers. At the end of the course, students were asked how effective each of the course activities were in learning the course material. On a five point scale, ranging from highest contribution to lowest, the percentage of students giving

  2. Terahertz quantum transport in semiconductor nanostructures with the UCSB free electron lasers

    SciTech Connect

    Allen, S.J.

    1995-12-31

    Quantum transport in semiconductor nanostructures takes on new dimensions in the presence of intense terahertz electric fields. Terahertz frequencies lift us into the regime where the scattering and relaxation is not so important and strong terahertz electric fields provided by the UCSB FEL`s explore non-linear dynamics far from the perturbative limit. New quantum transport channels that are assisted by the absorption or emission of a photon appear in current voltage characteristics. We will describe some of these experiments, the new phenomena they expose and the potential impact on future terahertz semiconductor electronics.

  3. Ion mobility spectrometry: A personal view of its development at UCSB

    PubMed Central

    Bowers, Michael T.

    2014-01-01

    Ion mobility is not a newly discovered phenomenon. It has roots going back to Langevin at the beginning of the 20th century. Our group initially got involved by accident around 1990 and this paper is a brief account of what has transpired here at UCSB the past 25 years in response to this happy accident. We started small, literally, with transition metal atomic ions and transitioned to carbon clusters, synthetic polymers, most types of biological molecules and eventually peptide and protein oligomeric assembly. Along the way we designed and built several generations of instruments, a process that is still ongoing. And perhaps most importantly we have incorporated theory with experiment from the beginning; a necessary wedding that allows an atomistic face to be put on the otherwise interesting but not fully informative cross section measurements. PMID:25147478

  4. Strong Earthquake Motion Estimates for the UCSB Campus, and Related Response of the Engineering 1 Building

    SciTech Connect

    Archuleta, R.; Bonilla, F.; Doroudian, M.; Elgamal, A.; Hueze, F.

    2000-06-06

    This is the second report on the UC/CLC Campus Earthquake Program (CEP), concerning the estimation of exposure of the U.C. Santa Barbara campus to strong earthquake motions (Phase 2 study). The main results of Phase 1 are summarized in the current report. This document describes the studies which resulted in site-specific strong motion estimates for the Engineering I site, and discusses the potential impact of these motions on the building. The main elements of Phase 2 are: (1) determining that a M 6.8 earthquake on the North Channel-Pitas Point (NCPP) fault is the largest threat to the campus. Its recurrence interval is estimated at 350 to 525 years; (2) recording earthquakes from that fault on March 23, 1998 (M 3.2) and May 14, 1999 (M 3.2) at the new UCSB seismic station; (3) using these recordings as empirical Green's functions (EGF) in scenario earthquake simulations which provided strong motion estimates (seismic syntheses) at a depth of 74 m under the Engineering I site; 240 such simulations were performed, each with the same seismic moment, but giving a broad range of motions that were analyzed for their mean and standard deviation; (4) laboratory testing, at U.C. Berkeley and U.C. Los Angeles, of soil samples obtained from drilling at the UCSB station site, to determine their response to earthquake-type loading; (5) performing nonlinear soil dynamic calculations, using the soil properties determined in-situ and in the laboratory, to calculate the surface strong motions resulting from the seismic syntheses at depth; (6) comparing these CEP-generated strong motion estimates to acceleration spectra based on the application of state-of-practice methods - the IBC 2000 code, UBC 97 code and Probabilistic Seismic Hazard Analysis (PSHA), this comparison will be used to formulate design-basis spectra for future buildings and retrofits at UCSB; and (7) comparing the response of the Engineering I building to the CEP ground motion estimates and to the design

  5. Ion mobility spectrometry: A personal view of its development at UCSB.

    PubMed

    Bowers, Michael T

    2014-09-15

    Ion mobility is not a newly discovered phenomenon. It has roots going back to Langevin at the beginning of the 20th century. Our group initially got involved by accident around 1990 and this paper is a brief account of what has transpired here at UCSB the past 25 years in response to this happy accident. We started small, literally, with transition metal atomic ions and transitioned to carbon clusters, synthetic polymers, most types of biological molecules and eventually peptide and protein oligomeric assembly. Along the way we designed and built several generations of instruments, a process that is still ongoing. And perhaps most importantly we have incorporated theory with experiment from the beginning; a necessary wedding that allows an atomistic face to be put on the otherwise interesting but not fully informative cross section measurements.

  6. As-Run Physics Analysis for the UCSB-1 Experiment in the Advanced Test Reactor

    SciTech Connect

    Nielsen, Joseph Wayne

    2015-09-01

    The University of California Santa Barbara (UCSB) -1 experiment was irradiated in the A-10 position of the ATR. The experiment was irradiated during cycles 145A, 145B, 146A, and 146B. Capsule 6A was removed from the test train following Cycle 145A and replaced with Capsule 6B. This report documents the as-run physics analysis in support of Post-Irradiation Examination (PIE) of the test. This report documents the as-run fluence and displacements per atom (DPA) for each capsule of the experiment based on as-run operating history of the ATR. Average as-run heating rates for each capsule are also presented in this report to support the thermal analysis.

  7. Research Highlights and Recent Enhancements at the NEES@UCSB Permanently Instrumented Field Sites

    NASA Astrophysics Data System (ADS)

    Steidl, J. H.; Hegarty, P.; Seale, S. H.; Lamere, T.; Stinson, E.; Wojcik, K.

    2012-12-01

    The NEES@UCSB facility consists of experimental facilities and cyber infrastructure for active testing and passive earthquake monitoring at instrumented geotechnical field sites. There have been a number of facility enhancements to both the experimental facilities and the cyber infrastructure for facilitating research at the sites and access to the data they produce. Through both the maintenance and operations and the NEES Research program funding sources, the scope of monitoring at the field sites continues to expand. A permanent cross-hole source and sensor array has been installed at both the Wildlife Liquefaction Array (WLA) and at the Garner Valley Downhole Array (GVDA) field sites. This enhancement provides daily measurements of shear-wave velocity and automated post-earthquake observations of velocity to examine soil modulus reduction and recovery. After a very large event, where nonlinear soil behavior is expected, cross-hole hammer source time intervals are as short as 5 minutes. While waiting for larger earthquakes to occur, the daily cross-hole hammer tests are providing interesting data on shear-wave velocity changes with seasonal water table height. Testing of a small reconfigurable structure at both the WLA and GVDA sites was conducted using the NEES@UCLA mobile shakers. The structure, which is a smaller version of a permanent structure at GVDA, has been left at the GVDA site and can be used for future experiments or site instrumentation enhancements. The large soil-foundation-interaction structure at GVDA has a 1D shaker mounted under its roof slab. This shaker runs nightly and the data provide insight into the influence of environmental conditions on the response of the structure. At WLA, additional sensors have been installed in a dense Shape Accelerometer Array (SAA). Each of the seven arrays contain 24 3-component MEMS accelerometers at approximately 0.3 meter spacing that span the upper 8 meters of the site, from above to below the liquefiable

  8. Preliminary test Results for a 25K Sorption Cryocooler Designed for the UCSB Long Duration Balloon Cosmic Microwave Background Radiation Experiment

    NASA Technical Reports Server (NTRS)

    Wade, L. A.; Levy, A. R.

    1996-01-01

    A continuous operation, vibration-free, long-life 25K sorption cryocooler has been built and is now in final integration and performance testing. This cooler wil be flown on the University of California at Santa Barbara (UCSB) Long Duration Balloon (LDB) Cosmic Microwave Background Radiation Experiment.

  9. An Investigation of Student Engagement in a Global Warming Debate: Proof of Concept for K-12 Outreach at UCSB

    NASA Astrophysics Data System (ADS)

    Schweizer, D. M.; Kelly, G. J.; Gautier, C.

    2001-05-01

    As part of a community outreach program, the first author worked with a physical science teacher to co-create and co-teach a nine week global warming for his three seventh grade classes. The nine week program culminated in a debate on the causes of global warming. Students were divided into three groups: scientists supporting human contributions to global warming; scientists opposed to human contributions to global warming; and leaders of nations. In this study we investigate how using debate as a pedagogical tool for addressing earth system science concepts can both promote active student learning and present a realistic and dynamic view of science. Grounded in the perspective of science as sociocultural practices, our investigation draws from studies of school science focusing on the socially constructed nature of knowing and the use of argument as a pedagogical tool. We present evidence illustrating how the use of argument provided opportunities for students to interpret data sets, formulate and defend arguments, challenge competing interpretations and unearth relevant scientific questions about the environment. We also provide evidence of how students were able to use scientific evidence to support their thought processes. The results of this outreach experience serve as a foundation for the development of a new K-12 outreach program, Earth Connection, scheduled to begin at the University of California Santa Barbara, in Summer, 2001. Through the Earth Connection Visiting Teacher Program, UCSB science educators will visit local schools to work directly with teachers in their classroom settings. The Visiting Teacher Program provides a mutual benefit to teachers and students. Students gain the experience of having an expert come into their classroom to involve them in the process of science. Teachers are provided with professional development opportunities to help them continue addressing relevant earth system science issues in their classrooms.

  10. LHC Olympics Workshop and String Phenomenology 2006 Conference

    SciTech Connect

    David Gross

    2006-10-01

    This is the final report of the organizers of the String Phenomenolgy program of which the LHC Olympics and the String Phenomenolgy conference were a part. In addition, it includes the list of talks from our website which comprise the online proceedings. The KITP no longer publishes conferences proceedings but rather makes recordings and visuals of all talks available on its website at www.kitp.ucsb.edu Program talks are available at http://online.kitp.ucsb.edu/online/strings06/ Conference talks are are at http://online.itp.ucsb.edu/online/strings_c06/ and LHC Olympics talks are at http://online.itp.ucsb.edu/online/lhco_c06/. These talks constitute the proceedings of these meetings.

  11. Coupling of Pore Pressure and Ground Motion: Further Studies using Data Recorded at the NEES@UCSB Wildlife Station

    NASA Astrophysics Data System (ADS)

    Seale, S. H.; Lavallee, D.; Archuleta, R. J.; Steidl, J. H.

    2012-12-01

    Pore pressure built up during an earthquake and the hazard associated with soil liquefaction present a major challenge for our society, as has been dramatically illustrated by recent large events (e.g. the 2011 Tohoku-oki, Japan, earthquake). There is consensus among scientists that a better assessment of the liquefaction risk requires a better understanding of the coupling between pore pressure and ground motion time histories. There is a basic need to investigate coupling as a function of the frequency content of the ground motion. The 2010 M7.2 El Mayor-Cucapah event has provided a remarkable opportunity to investigate and model the coupling. The event was well recorded at the NEES@UCSB Wildlife station located 110 km from the hypocenter. The station is equipped with three-component strong-motion accelerometers at the surface and in boreholes at various depths and with pore pressure transducers located in a saturated, liquefiable layer. The recorded pore pressure and ground motion time histories both have frequency content that is a function of time. We have applied a wavelet decomposition technique to the El Mayor ground motion and pore pressure data, looking for a linear relationship between the signals. The analysis shows that the early P-wave accelerations (vertical component) initiate pore pressure response. However, the pore pressure records contain a low-frequency component that dominates the signal with no corresponding low-frequency component in the ground motion signals recorded near-by. Although uncommon, a similar behavior has been also reported in the literature for pore pressure signals recoded during the 1980 Mammoth Lakes, California, earthquake. We have extended this work to the analysis of 4 other seismic events that have induced an increase in pore pressure at WLA. As the response of pore pressure is potentially a local phenomenon, we have restricted our analysis to recordings from the same site. These events include the M5.8 Ocotillo

  12. AVIRIS Reflectance Retrievals: UCSB Users Manual. Appendix 1

    NASA Technical Reports Server (NTRS)

    Roberts, Dar A.; Prentiss, Dylan

    2001-01-01

    The following write-up is designed to help students and researchers take Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) radiance data and retrieve surface reflectance. In the event that the software is not available, but a user has access to a reflectance product, this document is designed to provide a better understanding of how AVIRIS reflectance was retrieved. This guide assumes that the reader has both a basic understanding of the UNIX computing environment, and that of spectroscopy. Knowledge of the Interactive Data Language (IDL) and the Environment for Visualizing Images (ENVI) is helpful. This is a working document, and many of the fine details described in the following pages have been previously undocumented. After having read this document the reader should be able to process AVIRIS to reflectance, provided access to all of the code is possible. The AVIRIS radiance data itself is pre-processed at the Jet Propulsion Laboratory (JPL) in Pasadena, California. The first section of this paper describes how to read data from tape and byte-swap the data. Section 2 describes the procedure in preparing support files before running the 'h2o' suite of programs. Section 3 describes the four programs used in the process, h2olut9.f, h2ospl9.f, vlsfit9.f and rfl9.f.

  13. Progress Report on Disassembly and Post-Irradiation Experiments for UCSB ATR-2 Experiment

    SciTech Connect

    Nanstad, Randy K; Odette, G. R.; Robertson, Janet Pawel; Yamamoto, T

    2015-09-01

    The reactor pressure vessel (RPV) in a light-water reactor (LWR) represents the first line of defense against a release of radiation in case of an accident. Thus, regulations that govern the operation of commercial nuclear power plants require conservative margins of fracture toughness, both during normal operation and under accident scenarios. In the unirradiated condition, the RPV has sufficient fracture toughness such that failure is implausible under any postulated condition, including pressurized thermal shock (PTS) in pressurized water reactors (PWR). In the irradiated condition, however, the fracture toughness of the RPV may be severely degraded, with the degree of toughness loss dependent on the radiation sensitivity of the materials. As stated in previous progress reports, the available embrittlement predictive models, e.g. [1], and our present understanding of radiation damage are not fully quantitative, and do not treat all potentially significant variables and issues, particularly considering extension of operation to 80y.

  14. Computational simulation of materials notes for lectures given at UCSB, May 1996--June 1996

    SciTech Connect

    LeSar, R.

    1997-01-01

    This report presents information from a lecture given on the computational simulation of materials. The purpose is to introduce modern computerized simulation methods for materials properties and response.

  15. It Takes a Revolution--A Case Study of Facilities Service Improvements at UCSB.

    ERIC Educational Resources Information Center

    Gonzales, David

    2000-01-01

    Presents a case study on the successful revamping of the University of California Santa Barbara's Physical Facilities Maintenance and Operations Department. Each revamping step is discussed including issues involving morale and productivity, customer relations, outsourcing custodial services, teamwork, and the development of campus zone offices to…

  16. Kinetic Model for 1D aggregation of yeast ``prions''

    NASA Astrophysics Data System (ADS)

    Kunes, Kay; Cox, Daniel; Singh, Rajiv

    2004-03-01

    Mammalian prion proteins (PrP) are of public health interest because of mad cow and chronic wasting diseases. Yeast have proteins which can undergo similar reconformation and aggregation processes to PrP; yeast forms are simpler to experimentally study and model. Recent in vitro studies of the SUP35 protein(1), showed long aggregates and pure exponential growth of the misfolded form. To explain this data, we have extended a previous model of aggregation kinetics(2). The model assumes reconformation only upon aggregation, and includes aggregate fissioning and an initial nucleation barrier. We find for sufficiently small nucleation rates or seeding by small dimer concentrations that we can achieve the requisite exponential growth and long aggregates. We will compare to a more realistic stochastic kinetics model and present prelimary attempts to describe recent experiments on SUP35 strains. *-Supported by U.S. Army Congressionally Mandated Research Fund. 1) P. Chien and J.S. Weissman, Nature 410, 223 (2001); http://online.kitp.ucsb.edu/online/bionet03/collins/. 2) J. Masel, V.A.> Jansen, M.A. Nowak, Biophys. Chem. 77, 139 (1999).

  17. Remote Semi-State Preparation as SuperDense Quantum Teleportation

    NASA Astrophysics Data System (ADS)

    Bernstein, Herbert J.

    2011-03-01

    Recent advances in experimental technique make SuperDense Teleportation (SDT) possible. The effect uses remote state preparation to send more state-specifying parameters per bit than ordinary quantum teleportation (QT) can transmit. SDT uses a maximal entanglement to teleport the relative phases of an {n}-dimensional equimodular state. This means that one can send only {n}-1 of the total (2 n - 2) parameters -- comprising the relative phases and amplitudes -- of a general state. Nevertheless, for {n} >= 3 , SDT sends more of these state-specifying parameters than QT for a given number of classical bits. In the limit of large {n} the ratio is 2 to 1, hence the nomenclature Bennett suggested, SDT, by analogy with Super Dense Coding. Alice's measurements and Bob's transformations are simpler than in QT. The roles of Charles the state chooser, and Diana who deploys it, are different than in QT. I briefly review possible experimental realizations, including two that are under consideration at the present time by an experimental group leading in higher-dimension entanglement work. Supported in part by NSF grants PHY97-22614 & 07-58149 & KITP, UCSB, including an ITP Scholar-ship.

  18. Post-irradiation Examination Plan for ORNL and University of California Santa Barbara Assessment of UCSB ATR-2 Irradiation Experiment

    SciTech Connect

    Nanstad, R. K.; Yamamoto, T.; Sokolov, M. A.

    2014-01-25

    New and existing databases will be combined to support development of physically based models of transition temperature shifts (TTS) for high fluence-low flux (φ < 10{sup 11}n/cm{sup 2}-s) conditions, beyond the existing surveillance database, to neutron fluences of at least 1×10{sup 20} n/cm{sup 2} (>1 MeV). All references to neutron flux and fluence in this report are for fast neutrons (>1 MeV). The reactor pressure vessel (RPV) task of the Light Water Reactor Sustainability (LWRS) Program is working with various organizations to obtain archival surveillance materials from commercial nuclear power plants to allow for comparisons of the irradiation-induced microstructural features from reactor surveillance materials with those from similar materials irradiated under high flux conditions in test reactors

  19. High Temperature Mechanical Properties, Fractography and Synchrotron Studies of ATF clad materials from the UCSB-NSUF Irradiations.

    SciTech Connect

    Saleh, Tarik A.; Maloy, Stuart Andrew; Romero, Tobias J.; Sprouster, David; Ecker, Lynne

    2015-02-23

    A variety of tensile samples of Ferritic and Oxide Dispersion Strengthened (ODS or nanostructured ferritic) steels were placed the ATR reactor over 2 years achieving doses of roughly 4-6 dpa at temperatures of roughly 290°C. Samples were shipped to Wing 9 in the CMR facility at Los Alamos National Laboratory and imaged then tested in tension. This report summarizes the room temperature tensile tests, the elevated temperature tensile tests (300°C) and fractography and reduction of area calculations on those samples. Additionally small samples were cut from the undeformed grip section of these tensile samples and sent to the NSLS synchrotron for high energy X-ray analysis, initial results will be described here.

  20. The Kähler Ricci flow on surfaces of positive Kodaira dimension

    NASA Astrophysics Data System (ADS)

    Song, Jian; Tian, Gang

    2007-09-01

    The existence of K\\"ahler-Einstein metrics on a compact K\\"ahler manifold has been the subject of intensive study over the last few decades, following Yau's solution to Calabi's conjecture. The Ricci flow, introduced by Richard Hamilton has become one of the most powerful tools in geometric analysis. We study the K\\"ahler-Ricci flow on minimal surfaces of Kodaira dimension one and show that the flow collapses and converges to a unique canonical metric on its canonical model. Such a canonical is a generalized K\\"ahler-Einstein metric. Combining the results of Cao, Tsuji, Tian and Zhang, we give a metric classification for K\\"aher surfaces with a numerical effective canonical line bundle by the K\\"ahler-Ricci flow. In general, we propose a program of finding canonical metrics on canonical models of projective varieties of positive Kodaira dimension.

  1. Former Fermilab boss to lead Lawrence Berkeley National Laboratory

    NASA Astrophysics Data System (ADS)

    Gwynne, Peter

    2016-03-01

    Particle physicist Michael Witherell - current vice-chancellor for research at the University of California, Santa Barbara (UCSB) - has been appointed the next director of the Lawrence Berkeley National Laboratory (LBL).

  2. Potential for AP600 in-vessel retention through ex-vessel flooding

    SciTech Connect

    Rempe, J.L.; Knudson, D.L.; Allison, C.M.; Thinnes, G.L.; Atwood, C.L.

    1997-12-01

    External reactor vessel cooling (ERVC) is a new severe accident management strategy that involves flooding the reactor cavity to submerge the reactor vessel in an attempt to cool core debris that has relocated to the vessel lower head. Advanced and existing light water reactors (LWRs) are considering ERVC as an accident management strategy for in-vessel retention (IVR) of relocated debris. In the probabilistic risk assessment (PRA) for the AP600 design, Westinghouse credits ERVC for preventing vessel failure during postulated severe accidents with successful reactor coolant system (RCS) depressurization and reactor cavity flooding. To support the Westinghouse position on IVR, DOE contracted the University of California--Santa Barbara (UCSB) to produce the peer-reviewed report. To assist in the NRC`s evaluation of IVR of core melt by ex-vessel flooding of the AP6OO, the Idaho National Engineering and Environmental Laboratory (INEEL) was tasked to perform: An in-depth critical review of the UCSB study and the model that UCSB used to assess ERVC effectiveness; An in-depth review of the UCSB study peer review comments and of UCSB`s resolution method to identify areas where technical concerns weren`t addressed; and An independent analysis effort to investigate the impact of residual concerns on the margins to failure and conclusions presented in the UCSB study. This report summarizes results from these tasks. As discussed in Sections 1.1 and 1.2, INEEL`s review of the UCSB study and peer reviewer comments suggested that additional analysis was needed to assess: (1) the integral impact of peer reviewer-suggested changes to input assumptions and uncertainties and (2) the challenge present by other credible debris configurations. Section 1.3 summarized the corresponding analysis approach developed by INEEL. The remainder of this report provides more detailed descriptions of analysis methodology, input assumptions, and results.

  3. Report on the Program “Fluid-mediated particle transport in geophysical flows” at the Kavli Institute for Theoretical Physics, UC Santa Barbara, September 23 to December 12, 2013

    SciTech Connect

    Jenkins, James T.; Meiburg, Eckart; Valance, Alexandre

    2015-09-15

    The Kavli Institute of Theoretical Physics (KITP) program held at UC Santa Barbara in the fall of 2013 addressed the dynamics of dispersed particulate flows in the environment. By focusing on the prototypes of aeolian transport and turbidity currents, it aimed to establish the current state of our understanding of such two-phase flows, to identify key open questions, and to develop collaborative research strategies for addressing these questions. Here, we provide a brief summary of the program outcome.

  4. Transient Universe: Popular, Not so Popular & Knowable Unknowns

    NASA Astrophysics Data System (ADS)

    Bildsten, L.; Fryer, C.; Kulkarni, S.

    2006-03-01

    MOTIVATION & PURPOSE: This informal two day workshop is intended to bring together astronomers who monitor the sky for transient phenomena - a field which is poised to take off in the optical band, thanks to the exponential growth in the availability of giga pixel detectors, rapid computing and communication. For somewhat similar technological reasons, decimeter and decameter radio astronomy is also poised to grow in this area. The workshop will focus on astronomical opportunities with ongoing searches and discuss the possibilities with planned facilities in the near term. We hope to rapidly review the status of 'popular' sources (e.g. GRB afterglows, Supernovae, Machos), less popular events (e.g. Novae, geysers and gushers) and then move onto 'odd' but not hopelessly rare events. The spirit is to anticipate some of the discoveries by extending the astrophysical parameter space of known (or knowable) classes of transients. This workshop is part of the ongoing KITP Program "The Supernova Gamma Ray Burst Connection" and has received funding Los Alamos National Laboratory. We will follow the well honed KITP tradition of having fewer talks at the expense of long discussions. All talks will be recorded (per KITP tradition) and made available on the web for enjoyment, education and posterity. In lieu of a traditional poster sessions with old-fashioned easels we offer the Virtual Presence (organized by J. Bloom).

  5. Building a Comprehensive Mental Health System for Young Children

    ERIC Educational Resources Information Center

    Onunaku, Ngozi; Gilkerson, Linda; Ahlers, Therese

    2006-01-01

    Onunaku, Ahlers, and Gilkerson describe Illinois's effort to build infant mental health capacity within the Part C Early Intervention system and Wisconsin's effort to build capacity for infant and early childhood mental health services statewide across all systems that serve children. Because of multiple funding streams, families often experience…

  6. Performance of a low data rate speech codec for land-mobile satellite communications

    NASA Technical Reports Server (NTRS)

    Gersho, Allen; Jedrey, Thomas C.

    1990-01-01

    In an effort to foster the development of new technologies for the emerging land mobile satellite communications services, JPL funded two development contracts in 1984: one to the Univ. of Calif., Santa Barbara and the other to the Georgia Inst. of Technology, to develop algorithms and real time hardware for near toll quality speech compression at 4800 bits per second. Both universities have developed and delivered speech codecs to JPL, and the UCSB codec was extensively tested by JPL in a variety of experimental setups. The basic UCSB speech codec algorithms and the test results of the various experiments performed with this codec are presented.

  7. Cooperation Among Theorem Provers

    NASA Technical Reports Server (NTRS)

    Waldinger, Richard J.

    1998-01-01

    In many years of research, a number of powerful theorem-proving systems have arisen with differing capabilities and strengths. Resolution theorem provers (such as Kestrel's KITP or SRI's SNARK) deal with first-order logic with equality but not the principle of mathematical induction. The Boyer-Moore theorem prover excels at proof by induction but cannot deal with full first-order logic. Both are highly automated but cannot accept user guidance easily. The purpose of this project, and the companion project at Kestrel, has been to use the category-theoretic notion of logic morphism to combine systems with different logics and languages.

  8. What Parents Need to Know to Support Their Child on the Pathway to College: Learning from the ENLACE Experience

    ERIC Educational Resources Information Center

    W. K. Kellogg Foundation, 2004

    2004-01-01

    This brochure highlights two successful ENLACE partnership programs that connect college aspirations with actual college attainment for Latino students: (1) The "ENLACE y Avance" (Advance) partnership, led by the University of California, Santa Barbara (UCSB), whose innovative program of family home visits provides information about college to…

  9. From 6 to 163: The Chinese International Student Experience in a Time of Increased Enrollment at a University of California Campus

    ERIC Educational Resources Information Center

    Ramos, Adrian

    2013-01-01

    At UCSB the number of degree seeking undergraduate Chinese international students increased from 6 to 163 between 2010 and 2012. With such a controversial and much discussed topic of international student enrollment at U.S universities, this was the perfect time for me to interview Chinese international students. With the help of Kathy Charmaz'…

  10. Chicanos: A Checklist of Current Materials. No. 1, January-June, 1988.

    ERIC Educational Resources Information Center

    Guerena, Salvador, Comp.; Gonzalez, Raquel Quiroz, Comp.

    This is a bibliography of materials held in the Coleccion Tloque Nahuaque of the University of California at Santa Barbara (UCSB). It includes citations of monographs and reference tools about Chicanos written in both English and Spanish. The following categories are listed: agriculture; architecture; art; arts and crafts; bibliographies; border…

  11. Out of the Classroom and into the Heart of the Matter: A Case Study of University Student Residents' Reaction to Access to Multicultural Awareness Education

    ERIC Educational Resources Information Center

    Woodlief, Sharon E.

    2010-01-01

    The purpose of my study was to explore how, and to what extent, the UCSB faculty-in-residence program provided multicultural awareness education opportunities to student residents outside of the classroom. This research explored Housing and Residential Services, which housed the faculty-in-residence program whose mission is, in part, to provide…

  12. Culture in a Writing Program: An Organizational Case Study

    ERIC Educational Resources Information Center

    Orton, Haley Elizabeth

    2013-01-01

    This study explored the perceptions of the staff and faculty of one writing program in a large western university, the University of California, Santa Barbara (UCSB). The Writing Program had experienced significant changes including budgetary reductions since 2008 as well as turnover in leadership. These changes have impacted the culture of the…

  13. Final technical report, Symposium on New Theoretical Concepts and Directions in Catalysis

    SciTech Connect

    Metiu, Horia

    2014-08-22

    We organized in August 2013 a “Symposium on New Theoretical Concepts and Directions in Catalysis” with the participation of 20 invited distinguished quantum chemists and other researchers who use computations to study catalysis. Symposium website; http://catalysis.cnsi.ucsb.edu/

  14. Developing and Assessing an Online Research Writing Course

    ERIC Educational Resources Information Center

    Dean, Christopher W.

    2009-01-01

    "Developing and Assessing an Online Research Writing Course" discusses how the Writing Program at the University of California at Santa Barbara (UCSB) created a hybrid, online research writing course, Writing 50, and assessed that course. The assessment, which is at the center of this piece, was dovetailed with assessment literature in…

  15. Anomalies, conformal manifolds, and spheres

    DOE PAGES

    Gomis, Jaume; Hsin, Po-Shen; Komargodski, Zohar; Schwimmer, Adam; Seiberg, Nathan; Theisen, Stefan

    2016-03-04

    The two-point function of exactly marginal operators leads to a universal contribution to the trace anomaly in even dimensions. We study aspects of this trace anomaly, emphasizing its interpretation as a sigma model, whose target space $M$ is the space of conformal field theories (a.k.a. the conformal manifold). When the underlying quantum field theory is supersymmetric, this sigma model has to be appropriately supersymmetrized. As examples, we consider in some detail $N$ = (2; 2) and $N$ = (0; 2) supersymmetric theories in d = 2 and $N$ = 2 supersymmetric theories in d = 4. This reasoning leads tomore » new information about the conformal manifolds of these theories, for example, we show that the manifold is K ahler-Hodge and we further argue that it has vanishing K ahler class. For $N$ = (2; 2) theories in d = 2 and N = 2 theories in d = 4 we also show that the relation between the sphere partition function and the K ahler potential of $M$ follows immediately from the appropriate sigma models that we construct. Ultimately, along the way we find several examples of potential trace anomalies that obey the Wess-Zumino consistency conditions, but can be ruled out by a more detailed analysis.« less

  16. Investigating the impact of representation upon coarse-grained models

    NASA Astrophysics Data System (ADS)

    Foley, Thomas; Shell, M. Scott; Noid, William

    The first step in building a coarse-grained (CG) model is choosing a representation or `mapping' of the original system at a reduced resolution. In practice, the mapping is often chosen on the basis of `physical intuition.' Consequently this crucial step would greatly benefit from the development of systematic and principled methodologies. Accordingly, we have studied the relationship between the mapping and the resulting CG model. As a starting point, we have analytically derived, as a function of the CG mapping, the exact many-body potential of mean force (PMF) for the simple Gaussian Network Model (GNM) of protein fluctuations. We use this as a simple model for investigating the effect of the CG mapping upon the information loss and quality of the CG model. Moreover, by considering the GNM's for different proteins, we investigate the significance of high resolution structural features for the quality of the CG model. We acknowledge support from the NSF, Alfred P. Sloan Foundation, and KITP.

  17. [Physical modeling of sedimentary basins, magma mechanics, and molecular dynamics of aqueous solutions]. Technical progress report

    SciTech Connect

    Spera, F.J.

    1993-07-01

    Work at UCSB has been in four areas: (1) Convection in porous media, (2) Geochemical fluid dynamics, (3) Experimental rheometry of silicate melts and (4) Molecular dynamics of silicate solutions. In the past 18 months we have published, have in press or submitted 8 papers (see Appendix) and are currently at work on several others. Additionally, a number of abstracts have been published. A list of these works is presented in the Appendix.

  18. [Physical modeling of sedimentary basins, magma mechanics, and molecular dynamics of aqueous solutions

    SciTech Connect

    Spera, F.J.

    1993-01-01

    Work at UCSB has been in four areas: (1) Convection in porous media, (2) Geochemical fluid dynamics, (3) Experimental rheometry of silicate melts and (4) Molecular dynamics of silicate solutions. In the past 18 months we have published, have in press or submitted 8 papers (see Appendix) and are currently at work on several others. Additionally, a number of abstracts have been published. A list of these works is presented in the Appendix.

  19. Joint UK/US Radar Program progress reports for period December 1--31, 1994

    SciTech Connect

    Twogood, R.E.; Brase, J.M.; Mantrom, D.D.; Rino, C.; Chambers, D.H.; Robey, H.F.; Belyea, J.

    1995-01-23

    Topics discussed in this report are current accomplishments in many functions to include: airborne RAR/SAR, radar data processor, ground based SAR signal processing workstation, static airborne radar, multi-aperture space-time array radar, radar field experiments, data analysis and detection theory, management, radar data analysis, modeling and analysis, current meter array, UCSB wave tank, stratified flow facility, Russian Institute of Applied Physics, and budget status.

  20. Fluctuations below a stationary supercritical bifurcation to electroconvection in a nematic liquid crystal

    NASA Astrophysics Data System (ADS)

    Qiu, Xin-Liang; Ahlers, Guenter

    2003-03-01

    We report measurements of thermally driven fluctuations near the onset of electroconvection in a nematic liquid crystal (NLC). The cell (from E.H.C Co, Ltd Japan) had a nominal spacing of 25 μm and planar alignment. It was filled with the NLC Merck phase IV (N4). The NLC was doped with 0.1% by weight of tetra butylammonium bromide(TBAB) and the conductivity was near 9 × 10-7 (Ω m)-1 at 30^oC. The system was driven by an alternating voltage of frequency 25 Hz and amplitude V. The initial bifurcation to electroconvection was supercritical and yielded oblique stationary rolls. For small but negative ɛ ≡ V^2/V_c^2 - 1 the mean-square amplitude of the fluctuations was proportional to |ɛ|^-γ with γ larger than the value γ_LT = 1/2 given by linear theory (LT). This result differs from the one obtained earlier (M.A. Scherer ,G. Ahlers, F. Hörner, and I. Rehberg, Phys. Rev. Lett. 85), 3754 (2000); M.A. Scherer and G. Ahlers, Phys. Rev. E 65, 051101 (2002) for the NLC 5CB, which undergoes a supercritical Hopf bifurcation to oblique rolls and which yields γ ˜= 0.25 < γ_LT . We conclude that the two systems belong to different universality classes.

  1. Technical Report from the High Energy Physics Group of the University of California, Santa Barbara, DOE grant DE-FG02-91ER40618

    SciTech Connect

    Richman, Jeffrey; Berenstein, David; Campagnari, Claudio; Giddings, Steven; Incandela, Joseph; Nelson, Harry; Stuart, David; Witherell, Michael

    2014-09-11

    The research program of the UCSB high energy physics group encompasses advanced projects in both experimental and theoretical particle physics. This program has been strongly supported by the DOE Office of High Energy Physics for many years. The program addresses questions related to the properties of matter, the fundamental forces of nature, the origin and evolution of the universe, and the nature of spacetime. The mission of the group also has a strong educational component, and the training of physicists in advanced research is a key part of our program.

  2. MOLVIE: an interactive visualization environment for molecular structures.

    PubMed

    Sun, Huandong; Li, Ming; Xu, Ying

    2003-05-01

    A Molecular visualization interactive environment (MOLVIE), is designed to display three-dimensional (3D) structures of molecules and support the structural analysis and research on proteins. The paper presents the features, design considerations and applications of MOLVIE, especially the new functions used to compare the structures of two molecules and view the partial fragment of a molecule. Being developed in JAVA, MOLVIE is platform-independent. Moreover, it may run on a webpage as an applet for remote users. MOLVIE is available at http://www.cs.ucsb.edu/~mli/Bioinf/software/index.html. PMID:12725967

  3. Progress reports for period November 1--30, 1994 -- Joint UK/US Radar Program

    SciTech Connect

    Twogood, R.E.; Brase, J.M.; Mantrom, D.D.; Chambers, D.H.; Robey, H.F.

    1994-12-19

    This report gives the principle investigator, objectives, recent accomplishments, milestones for reporting period, expected milestones for ensuing period, other issues and planned expenditures for the following programs: airborne RAR/SAR; radar data processor; ground-based SAR signal processing workstation; static airborne radar; multi-aperture space-time array radar; radar field experiments; data analysis and detection theory; management; E-2C radar data analysis;modeling and analysis; current meter array; UCSB wave tank; stratified flow facility; and IR sensor system. Budget status is also given.

  4. Progress reports for October 1994 -- Joint UK/US Radar Program

    SciTech Connect

    Twogood, R.E.; Brase, J.M.; Mantrom, D.D.; Chambers, D.H.; Robey, H.F.

    1994-11-18

    This report gives the principle investigator, objectives, recent accomplishments, milestones for reporting period, expected milestones for ensuing period, other issues and planned expenditures for each of the following programs: airborne RAR/SAR; radar data processor; ground-based SAR signal processing workstation; static airborne radar; multi-aperture space-time array radar; radar field experiments; data analysis and detection theory; management; E-2C radar data analysis; modeling and analysis; current meter array; UCSB wave tank; stratified flow facility; and IR sensor system. Finally the budget status is given.

  5. Earth science research

    NASA Technical Reports Server (NTRS)

    Botkin, Daniel B.

    1987-01-01

    The analysis of ground-truth data from the boreal forest plots in the Superior National Forest, Minnesota, was completed. Development of statistical methods was completed for dimension analysis (equations to estimate the biomass of trees from measurements of diameter and height). The dimension-analysis equations were applied to the data obtained from ground-truth plots, to estimate the biomass. Classification and analyses of remote sensing images of the Superior National Forest were done as a test of the technique to determine forest biomass and ecological state by remote sensing. Data was archived on diskette and tape and transferred to UCSB to be used in subsequent research.

  6. Terahertz signature characterization of bio-simulants

    NASA Astrophysics Data System (ADS)

    Majewski, Alexander J.; Miller, Peter; Abreu, Rene; Grotts, Jeffrey; Globus, Tatiana; Brown, Elliott

    2005-05-01

    Collaboration with the University of Virginia (UVa) and the University of California, Santa Barbara (UCSB) has resulted in the collection of signature data in the THz region of the spectrum for ovalbumin, Bacillus Subtilis (BG) and RNA from MS2 phage. Two independent experimental measurement systems were used to characterize the bio-simulants. Prior to our efforts, only a limited signature database existed. The goal was to evaluate a larger ensemble of biological agent simulants (BG, MS2 and ovalbumin) by measuring their THz absorption spectra. UCSB used a photomixer spectrometer and UVa a Fourier Transform spectrometer to measure absorption spectra. Each group used different sample preparation techniques and made multiple measurements to provide reliable statistics. Data processing culminated in applying proprietary algorithms to develop detection filters for each simulant. Through a covariance matrix approach, the detection filters extract signatures over regions with strong absorption and ignore regions with large signature variation (noise). The discrimination capability of these filters was also tested. The probability of detection and false alarm for each simulant was analyzed by each simulant specific filter. We analyzed a limited set of Bacillus thuringiensis (BT) data (a near neighbor to BG) and were capable of discriminating between BT and BG. The signal processing and filter construction demonstrates signature specificity and filter discrimination capabilities.

  7. Using the Web to Track Student Progress in Large Classes

    NASA Astrophysics Data System (ADS)

    Martin, Christopher L.

    1998-04-01

    This past year we have begun using a new web based program for one of our large introductory physics courses that allows students to track their own progress in the course, while enhancing data collection and simplifying course administration for the faculty. Students take a weekly pre-quiz on material to be presented in lecture the following week, which they can take as many times as they like to improve their score. Faculty then use the statistics from the pre-quiz to focus on common student errors. Faculty, TAs, and graders all use the web as a centrally accessible grade-book, so students can use the web to check the accuracy their homework and exam grades in the course, and track their own progress in the course. I will discuss the effort required to integrate a system of this type into a course, and the comments from students, faculty, and TAs after using the system. (please visit ucsb.edu/ phys1/visitor.html>http://www.physics.ucsb.edu/ ~phys1/visitor.html for more information and a demonstration)

  8. Initial source and site characterization studies for the U.C. Santa Barbara campus

    SciTech Connect

    Archuleta, R.; Nicholson, C.; Steidl, J.; Gurrola, L.; Alex, C.; Cochran, E.; Ely, G.; Tyler, T.

    1997-12-01

    The University of California Campus-Laboratory Collaboration (CLC) project is an integrated 3 year effort involving Lawrence Livermore National Laboratory (LLNL) and four UC campuses - Los Angeles (UCLA), Riverside (UCR), Santa Barbara (UCSB), and San Diego (UCSD) - plus additional collaborators at San Diego State University (SDSU), at Los Alamos National Laboratory and in industry. The primary purpose of the project is to estimate potential ground motions from large earthquakes and to predict site-specific ground motions for one critical structure on each campus. This project thus combines the disciplines of geology, seismology, geodesy, soil dynamics, and earthquake engineering into a fully integrated approach. Once completed, the CLC project will provide a template to evaluate other buildings at each of the four UC campuses, as well as provide a methodology for evaluating seismic hazards at other critical sites in California, including other UC locations at risk from large earthquakes. Another important objective of the CLC project is the education of students and other professional in the application of this integrated, multidisciplinary, state-of-the-art approach to the assessment of earthquake hazard. For each campus targeted by the CLC project, the seismic hazard study will consist of four phases: Phase I - Initial source and site characterization, Phase II - Drilling, logging, seismic monitoring, and laboratory dynamic soil testing, Phase III - Modeling of predicted site-specific earthquake ground motions, and Phase IV - Calculations of 3D building response. This report cover Phase I for the UCSB campus and incudes results up through March 1997.

  9. Free-electron laser-based pulsed electron paramagnetic resonance

    NASA Astrophysics Data System (ADS)

    Takahashi, Susumu; Sherwin, Mark S.; Ramian, Gerald; Brunel, Louis-Claude; van Tol, Johan

    2008-03-01

    High-power pulsed electron paramagnetic resonance (EPR) is extremely useful to study the ultrafast dynamics of spins. At present, most high-power pulsed EPR spectrometers operate near the X-band frequency of 9.5 GHz with kW-level power. A trend in the evolution of next generation pulsed EPR is for higher magnetic field and frequency, both for finer spectral and time resolution and because motional averaging becomes negligible. Since the linewidth of resonances studied by pulsed EPR tends to be extremely narrow, the source radiation also has to be stable and have narrow bandwidth. High-power pulsed EPR, using few-ns pulses to rapidly manipulate spins for spin-echo and related experiments, has been demonstrated at 95 GHz using kW- power Klystron-based sources. A bottleneck for higher frequency pulsed EPR spectroscopy is a lack of sources with high power and narrow bandwidth. The University of California Santa Barbara (UCSB) free-electron lasers (FEL) are potential sources for high-power pulsed EPR because they generate kW of power tunable from 120 GHz to 4.7 THz. We present the current status of the UCSB FEL-based 240 GHz pulsed EPR spectrometer.

  10. Many-body Localization Transition in Rokhsar-Kivelson-type wave functions

    NASA Astrophysics Data System (ADS)

    Chen, Xiao; Yu, Xiongjie; Cho, Gil Young; Clark, Bryan; Fradkin, Eduardo

    We construct a family of many-body wave functions to study the many-body localization phase transition. The wave functions have a Rokhsar-Kivelson form, in which the weight for the configurations are chosen from the Gibbs weights of a classical spin glass model, known as the Random Energy Model, multiplied by a random sign structure to represent a highly excited state. These wave functions show a phase transition into an MBL phase. In addition, we see three regimes of entanglement scaling with subsystem size: scaling with entanglement corresponding to an infinite temperature thermal phase, constant scaling, and a sub-extensive scaling between these limits. Near the phase transition point, the fluctuations of the Renyi entropies are non-Gaussian. We find that Renyi entropies with different Renyi index transition into the MBL phase at different points and have different scaling behavior, suggesting a multifractal behavior. This work was supported in part by DMR-1064319 and DMR-1408713 (XC,GYC,EF) at the University of Illinois, PHY11-25915 at KITP (EF), DOE, SciDAC FG02-12ER46875 (BKC and XY), and the Brain Korea 21 PLUS Project of Korea Government (GYC).

  11. Competing Orders in a Dipolar Bose - Fermi Mixture on a Square Optical Lattice: Mean-Field Perspective

    NASA Astrophysics Data System (ADS)

    Ling, Hong; Scaramaazza, Jasen; Kain, Ben

    2015-05-01

    We study superfluid pairings of two-component fermions interacting by exchanging virtual phonons of a dipolar condensate in an optical lattice that preserves the symmetry of D4. We construct, within the Hartree-Fock-Bogoliubov theory, the matrix representation of the linearized gap equation in the irreducible representations of D4. We find that each matrix element, which is a four-dimensional (4D) integral in momentum space, can be put in a separable form involving a 1D integral, which is only a function of temperature and the chemical potential, and a pairing-specific ``effective'' interaction, which is an analytical function of the parameters that characterize Fermi-Fermi interactions. We analyze the critical temperatures of various competing orders (superfluids with s-, dx2-y2-, dxy-, and g-wave symmetries and density waves) as functions of different system parameters in both the absence and presence of the dipolar interaction. We find that tuning a dipolar interaction can dramatically enhance various unconventional pairings. KITP, University of Santa Barbara; ITAMP, Harvard-Smithsonian Center for Astrophysics.

  12. High Energy Theory Workshops and Visitors at the Michigan Center for Theoretical Physics FY15

    SciTech Connect

    Pierce, Aaron T.

    2015-09-18

    The String theory workshop was held from March 4-7, 2015 on the University of Michigan campus. Local organizers were Gordon Kane and Aaron Pierce. Piyush Kumar (Yale), Jim Halverson (KITP), Bobby Acharya (ICTP) and Sven Krippendorf (Oxford) served as external organizers.The meeting focused on the status of work to project 10 or 11 dimensional string/M theories onto our 4 spacetime dimensions (compactification). The workshop had 31 participants, half from outside the U.S. Participants were encouraged to focus on predictions for recent and forthcoming data, particularly for Higgs physics and LHC and dark matter, rather than on the traditional approach of embedding the Standard Model particles and forces. The Higgs boson sympoosium was locally organized by James Wells (chair), Aaron Pierce and Jianming Qian. Additional input in the early stages by Stefan Pokorski (Warsaw) who was unable to attend in the end. The workshop consistent of 22 talks from experts around the world, both theoretical and experimental. Experimentalists summarized the current state of knowledge of the Higgs boson and its varients. The theory talks ranged from technical calculations of Standard Model processes to speculative novel ideas. The YHET visitor program invited weekly young visitors to the University of Michigan campus to present their work. This year 24 participants came under the program, with 17 of them receiving at least partial support for their visits.

  13. Coarse-graining using the relative entropy and simplex-based optimization methods in VOTCA

    NASA Astrophysics Data System (ADS)

    Rühle, Victor; Jochum, Mara; Koschke, Konstantin; Aluru, N. R.; Kremer, Kurt; Mashayak, S. Y.; Junghans, Christoph

    2014-03-01

    Coarse-grained (CG) simulations are an important tool to investigate systems on larger time and length scales. Several methods for systematic coarse-graining were developed, varying in complexity and the property of interest. Thus, the question arises which method best suits a specific class of system and desired application. The Versatile Object-oriented Toolkit for Coarse-graining Applications (VOTCA) provides a uniform platform for coarse-graining methods and allows for their direct comparison. We present recent advances of VOTCA, namely the implementation of the relative entropy method and downhill simplex optimization for coarse-graining. The methods are illustrated by coarse-graining SPC/E bulk water and a water-methanol mixture. Both CG models reproduce the pair distributions accurately. SYM is supported by AFOSR under grant 11157642 and by NSF under grant 1264282. CJ was supported in part by the NSF PHY11-25915 at KITP. K. Koschke acknowledges funding by the Nestle Research Center.

  14. The effect of Ti-B on stabilization of Cu-Zn-Al martensite

    SciTech Connect

    Stipcich, M.; Romero, R. |

    1998-10-05

    The application of shape memory effect in devices requires, in many cases, stable and reliable transformation temperatures. However, as a consequence of diffusional processes, in Cu-based shape memory alloys, reverse transformation temperature significantly rises after aging at temperatures above room temperature. This generally unwanted behavior is usually referred to as the stabilization of martensite. Numerous investigations have been carried out on this subject as reviewed by Ahlers and Chandrasekaran et al. Within the Cu-based alloys the Cu-Zn-Al are claimed to be more prone to stabilization than Cu-Al-Ni on aging. It has been proposed that in the Cu-Zn-Al the stabilization is due to the interchange of Cu and Zn atoms assisted by vacancies, changing, consequently, the long range order inherited from the {beta} phase. In the present work, the authors investigate the stabilization behavior of polycrystalline samples of stress induced Cu-Zn-Al and Cu-Zn-Al-B martensite.

  15. Ability of a low-dimensional model to predict geometry-dependent dynamics of large-scale coherent structures in turbulence.

    PubMed

    Bai, Kunlun; Ji, Dandan; Brown, Eric

    2016-02-01

    We test the ability of a general low-dimensional model for turbulence to predict geometry-dependent dynamics of large-scale coherent structures, such as convection rolls. The model consists of stochastic ordinary differential equations, which are derived as a function of boundary geometry from the Navier-Stokes equations [Brown and Ahlers, Phys. Fluids 20, 075101 (2008); Phys. Fluids 20, 105105 (2008)]. We test the model using Rayleigh-Bénard convection experiments in a cubic container. The model predicts a mode in which the alignment of a convection roll stochastically crosses a potential barrier to switch between diagonals. We observe this mode with a measured switching rate within 30% of the prediction. PMID:26986423

  16. The oscillation modes of large-scale circulation in turbulent Rayleigh-Bénard convection

    NASA Astrophysics Data System (ADS)

    Ji, Dandan; Bai, Kunlun; Brown, Eric

    2014-11-01

    We present measurement of the large-scale circulation (LSC) of turbulent Rayleigh-Bénard convection of cubic cell. We found the reorientation events by rotation through the LSC orientation θ0 with a multi-peaked probability distribution p (θ0) , as predicted by the model presented by Brown and Ahlers (Phys. Fluids, 2008). In contrast to the results of oscillation modes in cylindrical cell, when the LSC was confined into one corner, the flow didn't exhibit the twisting and sloshing oscillation with a well-defined periodicity. The phase relation of θ0 at different heights in the cell was not fixed, so LSC was not in a plane. The sloshing displacement of the LSC from a center plane exhibited random switching between two states.

  17. A low-dimensional model for large-scale coherent structures

    NASA Astrophysics Data System (ADS)

    Bai, Kunlun; Ji, Dandan; Brown, Eric

    2015-11-01

    We demonstrate a methodology to predict the dynamics of the large-scale coherent structures in turbulence using a simple low dimensional stochastic model proposed by Brown and Ahlers (Phys. Fluids, 2008). The model terms are derived from the Navier-Stokes equations, including a potential term depending on the geometry of the system. The model has previously described several dynamical modes of the large-scale circulation (LSC) in turbulent Rayleigh-Bénard convection. Here we test a model prediction for the existence of a new mode where the LSC stochastically changes direction to align with different diagonals of a cubic container. The model successfully predicts the switching rate of the LSC at different tilting conditions. The success of the prediction of the switching mode demonstrates that a low-dimensional turbulent model can quantitatively predict the existence and properties of different dynamical states that result from boundary geometry.

  18. Ability of a low-dimensional model to predict geometry-dependent dynamics of large-scale coherent structures in turbulence.

    PubMed

    Bai, Kunlun; Ji, Dandan; Brown, Eric

    2016-02-01

    We test the ability of a general low-dimensional model for turbulence to predict geometry-dependent dynamics of large-scale coherent structures, such as convection rolls. The model consists of stochastic ordinary differential equations, which are derived as a function of boundary geometry from the Navier-Stokes equations [Brown and Ahlers, Phys. Fluids 20, 075101 (2008); Phys. Fluids 20, 105105 (2008)]. We test the model using Rayleigh-Bénard convection experiments in a cubic container. The model predicts a mode in which the alignment of a convection roll stochastically crosses a potential barrier to switch between diagonals. We observe this mode with a measured switching rate within 30% of the prediction.

  19. High-Efficiency Non-Polar GaN-Based LEDs

    SciTech Connect

    Paul Fini

    2010-11-30

    Inlustra Technologies with subcontractor U.C. Santa Barbara conducted a project with the principle goal of demonstrating high internal quantum efficiency blue (430 nm) and green (540nm) light emitting diodes (LEDs) on low-defect density non-polar GaN wafers. Inlustra pursued the fabrication of smooth thick a-plane and m-plane GaN films, as well as defect reduction techniques such as lateral epitaxial overgrowth (LEO) to uniformly lower dislocation density in these films. Limited free-standing wafers were produced as well. By the end of the reporting period, Inlustra had met its milestone of dislocation reduction to < 5 x 10{sup 6} cm{sup -2}. Stacking faults were still present in appreciable density ({approx} 1 x 10{sup 5} cm{sup -1}), but were not the primary focus of defect reduction since there have been no published studies establishing their detrimental effects on LED performance. Inlustra's LEO progress built a solid foundation upon which further commercial development of GaN substrates will occur. UCSB encountered multiple delays in its LED growth and fabrication efforts due to unavoidable facilities outages imposed by ongoing construction in an area adjacent to the metalorganic chemical vapor deposition (MOCVD) laboratory. This, combined with the large amount of ab initio optimization required for the MOCVD system used during the project, resulted in unsatisfactory LED progress. Although numerous blue-green photoluminescence results were obtained, only a few LED structures exhibited electroluminescence at appreciable levels. UCSB also conducting extensive modeling (led by Prof. Van de Walle) on the problem of non-radiative Auger recombination in GaN-based LED structures, which has been posited to contribute to LED efficiency 'droop' at elevated current density. Unlike previous modeling efforts, UCSB's approach was truly a first-principles ab initio methodology. Building on solid numerical foundations, the Auger recombination rates of In{sub x}Ga{sub 1-x

  20. CUES - A Study Site for Measuring Snowpack Energy Balance in the Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Bair, Edward; Dozier, Jeff; Davis, Robert; Colee, Michael; Claffey, Keran

    2015-09-01

    Accurate measurement and modeling of the snowpack energy balance are critical to understanding the terrestrial water cycle. Most of the water resources in the western US come from snowmelt, yet statistical runoff models that rely on the historical record are becoming less reliable because of a changing climate. For physically based snow melt models that do not depend on past conditions, ground based measurements of the energy balance components are imperative for verification. For this purpose, the US Army Corps of Engineers Cold Regions Research and Engineering Laboratory (CRREL) and the University of California, Santa Barbara (UCSB) established the “CUES” snow study site (CRREL/UCSB Energy Site, http://www.snow.ucsb.edu/) at 2940 m elevation on Mammoth Mountain, California. We describe CUES, provide an overview of research, share our experience with scientific measurements, and encourage future collaborative research. Snow measurements began near the current CUES site for ski area operations in 1969. In the 1970s, researchers began taking scientific measurements. Today, CUES benefits from year round gondola access and a fiber optic internet connection. Data loggers and computers automatically record and store over 100 measurements from more than 50 instruments each minute. CUES is one of only five high altitude mountain sites in the Western US where a full suite of energy balance components are measured. In addition to measuring snow on the ground at multiple locations, extensive radiometric and meteorological measurements are recorded. Some of the more novel measurements include scans by an automated terrestrial LiDAR, passive and active microwave imaging of snow stratigraphy, microscopic imaging of snow grains, snowflake imaging with a multi-angle camera, fluxes from upward and downward looking radiometers, snow water equivalent from different types of snow pillows, snowmelt from lysimeters, and concentration of impurities in the snowpack. We give an

  1. [Nucleosynthesis, Rotation and Magnetism in Accreting Neutron Stars

    NASA Technical Reports Server (NTRS)

    Bildsten, Lars

    2004-01-01

    This is my final report on the NASA ATP grant on nucleosynthesis, rotation and magnetism in accreting neutron stars (NAG5-8658). In my last two reports, I summarized the science that I have accomplished, which covered a large range of topics. For this report, I want to point out the graduate students that were partially supported on this grant and where they are now. Andrew Cumming is an Assistant Professor of Physics at McGill University, Greg Ushomirsky is a researcher at MIT s Lincoln Laboratories, Dean Townsley is a postdoctoral researcher at Univ. of Chicago, Chris Deloye is a postdoctoral researcher at Northwestern University. The other two students, Phil Chang and Tony Piro, are still at UCSB and will be completing their PhD s in Summer 05 and Summer 06.

  2. Cold dark matter and degree-scale cosmic microwave background anisotropy statistics after COBE

    NASA Technical Reports Server (NTRS)

    Gorski, Krzysztof M.; Stompor, Radoslaw; Juszkiewicz, Roman

    1993-01-01

    We conduct a Monte Carlo simulation of the cosmic microwave background (CMB) anisotropy in the UCSB South Pole 1991 degree-scale experiment. We examine cold dark matter cosmology with large-scale structure seeded by the Harrison-Zel'dovich hierarchy of Gaussian-distributed primordial inhomogeneities normalized to the COBE-DMR measurement of large-angle CMB anisotropy. We find it statistically implausible (in the sense of low cumulative probability F lower than 5 percent, of not measuring a cosmological delta-T/T signal) that the degree-scale cosmological CMB anisotropy predicted in such models could have escaped a detection at the level of sensitivity achieved in the South Pole 1991 experiment.

  3. Riparian restoration framework for the Upper Gila River, Arizona

    USGS Publications Warehouse

    Orr, Bruce K.; Leverich, Glen L.; Diggory, Zooey E.; Dudley, Tom L.; Hatten, James R.; Hultine, Kevin R.; Johnson, Matthew P.; Orr, Devyn A.

    2014-01-01

    This technical report summarizes the methods and results of a comprehensive riparian restoration planning effort for the Gila Valley Restoration Planning Area, an approximately 53-mile portion of the upper Gila River in Arizona (Figure 1-1). This planning effort has developed a Restoration Framework intended to deliver science-based guidance on suitable riparian restoration actions within the ecologically sensitive river corridor. The framework development was conducted by a restoration science team, led by Stillwater Sciences with contributions from researchers at the Desert Botanical Garden (DBG), Northern Arizona University (NAU), University of California at Santa Barbara (UCSB), and U.S. Geological Survey (USGS). All work was coordinated by the Gila Watershed Partnership of Arizona (GWP), whose broader Upper Gila River Project Area is depicted in Figure 1-1, with funding from the Walton Family Foundation’s Freshwater Initiative Program.

  4. Strategies for fitting nonlinear ecological models in R, AD Model Builder, and BUGS

    USGS Publications Warehouse

    Bolker, Benjamin M.; Gardner, Beth; Maunder, Mark; Berg, Casper W.; Brooks, Mollie; Comita, Liza; Crone, Elizabeth; Cubaynes, Sarah; Davies, Trevor; de Valpine, Perry; Ford, Jessica; Gimenez, Olivier; Kéry, Marc; Kim, Eun Jung; Lennert-Cody, Cleridy; Magunsson, Arni; Martell, Steve; Nash, John; Nielson, Anders; Regentz, Jim; Skaug, Hans; Zipkin, Elise

    2013-01-01

    1. Ecologists often use nonlinear fitting techniques to estimate the parameters of complex ecological models, with attendant frustration. This paper compares three open-source model fitting tools and discusses general strategies for defining and fitting models. 2. R is convenient and (relatively) easy to learn, AD Model Builder is fast and robust but comes with a steep learning curve, while BUGS provides the greatest flexibility at the price of speed. 3. Our model-fitting suggestions range from general cultural advice (where possible, use the tools and models that are most common in your subfield) to specific suggestions about how to change the mathematical description of models to make them more amenable to parameter estimation. 4. A companion web site (https://groups.nceas.ucsb.edu/nonlinear-modeling/projects) presents detailed examples of application of the three tools to a variety of typical ecological estimation problems; each example links both to a detailed project report and to full source code and data.

  5. GEMS at OVRO: Education Courses in Radio Astronomy

    NASA Astrophysics Data System (ADS)

    Beasley, A. J.; Schuck, B. J.; Dawson, L.; Hodges, M. W.; Mercer, A. J.

    2004-05-01

    A collaboration between the Caltech Owens Valley Radio Observatory and the UCSB Sierra Nevada Aquatic Research Laboratory has been formed to provide an astronomy-related hands-on summer instruction course for elementary-level students in eastern California. We are using the OVRO 40-m telescope to reinforce the LHS GEMS "Messages from Space" curriculum; the control room of the telescope has been remodelled into a classroom, and a user-friendly control and data acquisition system for the 40-m has been developed. After a successful pilot program in 2003 where students spent time searching for SETI signals from nearby bright stars, we are continuing to expand our suite of instructional experiments.

  6. Workshops on Enhancing the Impact of University Research on Critical Technologies. Final report

    SciTech Connect

    Eisenberger, Peter M.

    1998-12-01

    This proposal was designed to initiate a series of workshops in which participants from universities, government and industry would look strategically at selected areas of technological and societal importance. One of these workshops, dedicated to the discussion of how materials modeling can solve critical problems in industry, held at the Institute for Theoretical Physics, University of California Santa Barbara, January 7 through 11, 1996. ''Modeling of Industrial Materials: Connecting Atomistic and Continuum Scales'' was the first of a coordinated series of workshops, spanning over two years, being organized by a group of academic scientists at UCSB, MIT, and the Swiss Federal Institute of Technology Zurich (ETH). On the premise that materials research focused on technology also presents fundamental scientific challenges, the Workshop sought to identify specific areas of industrial needs and opportunities for materials modeling, interpreted as theory and simulation across all the relevant length scales, and to stimulate meaningful university-industry partnerships.

  7. SeaWiFS Postlaunch Technical Report Series. Volume 11; SeaWIFS Postlaunch Calibration and Validation Analyses

    NASA Technical Reports Server (NTRS)

    Hooker, Stanford B. (Editor); Firestone, Elaine R. (Editor); OReilly, John E.; Maritorena, Stephane; OBrien, Margaret C.; Siegel, David A.; Toole, Dierdre; Mueller, James L.; Mitchell, B. Greg; Kahru, Mati; Chavez, Francisco P.; Strutton, P.

    2000-01-01

    Volume 11 continues the sequential presentation of postlaunch data analysis and algorithm descriptions begun in Volume 9. Chapters 1 and 2 present the OC2 (version 2) and OC4 (version 4) chlorophyll a algorithms used in the SeaWiFS data second and third reprocessings, August 1998 and May 2000, respectively. Chapter 3 describes a revision of the K(490) algorithm designed to use water-leaving radiances at 490 nm which was implemented for the third reprocessing. Finally, Chapter 4 is an analysis of in situ radiometer calibration data over several years at the University of California, Santa Barbara (UCSB) to establish the temporal consistency of their in-water optical measurements.

  8. Limits on cold dark matter cosmologies from new anisotropy bounds on the cosmic microwave background

    NASA Technical Reports Server (NTRS)

    Vittorio, Nicola; Meinhold, Peter; Lubin, Philip; Muciaccia, Pio Francesco; Silk, Joseph

    1991-01-01

    A self-consistent method is presented for comparing theoretical predictions of and observational upper limits on CMB anisotropy. New bounds on CDM cosmologies set by the UCSB South Pole experiment on the 1 deg angular scale are presented. An upper limit of 4.0 x 10 to the -5th is placed on the rms differential temperature anisotropy to a 95 percent confidence level and a power of the test beta = 55 percent. A lower limit of about 0.6/b is placed on the density parameter of cold dark matter universes with greater than about 3 percent baryon abundance and a Hubble constant of 50 km/s/Mpc, where b is the bias factor, equal to unity only if light traces mass.

  9. ASAP progress and expenditure report for the month of February 1--29, 1996

    SciTech Connect

    Twogood, R.E.; Brase, J.M.; Chambers, D.H.; Mantrom, D.M.; Miller, M.G.; Newman, M.J.; Robey, H.F.; Vigars, M.

    1996-03-20

    This is the ASAP progress and expenditure report for the month of February, 1996. The individual projects` report includes the sponsoring organization, the project identification, the principal investigator, long term objectives, short term objectives, accomplishments this reporting period, identification of issues or concerns, project budget estimate for the fiscal year, and monthly actual and year to date expenditures. The research project concerns a joint US/UK program to develop a high-priority radar system based on real aperture and synthetic aperature radar. Topics being researched include airborne RAR/SAR; radar data processor; ground-based SAR signal processing workstation; static airborne radar; radar field experiments; data analysis and detection theory; program management; modeling and analysis; UCSB wave tank; stratified wave tank; and experiments in a thermo-stratified tank at the Institute of Applied Physics, Russia.

  10. A unified interpretation of one-fifth to full scale thermal mixing experiments related to Pressurized Thermal Shock

    SciTech Connect

    Theofanous, T.G.; Yan, H. . Dept. of Chemical and Nuclear Engineering)

    1991-04-01

    Thermal mixing in relation to Pressurized Thermal Shock has been examined experimentally throughout the world in a variety of scales. These include the CREARE-1/5, the IVO/IVO(NRC)-2/5, the PURDUE(UCSB)-1/2, the CREARE-1/2, the HDR-1/1 and the UPTF-1/1 test facilities. The Regional Mixing Model and the associated computer programs REMIX and NEWMIX are used to interpret these data, in this report, in a comprehensive fashion. These interpretations indicate that cooldown transients and degree of stratification can be predicted with confidence. Universal stratification solutions are also provided, in graphical form, and a simple procedure for hand-calculation is also described. 40 refs., 20 figs., 17 tabs.

  11. Using observed warming to identify hazards to Mozambique maize production

    USGS Publications Warehouse

    Funk, Christopher C.; Harrison, Laura; Eilerts, Gary

    2011-01-01

    New Perspectives on Crop Yield Constraints because of Climate Change. Climate change impact assessments usually focus on changes to precipitation because most global food production is from rainfed cropping systems; however, other aspects of climate change may affect crop growth and potential yields.A recent (2011) study by the University of California, Santa Barbara (UCSB) Climate Hazards Group, determined that climate change may be affecting Mozambique's primary food crop in a usually overlooked, but potentially significant way (Harrison and others, 2011). The study focused on the direct relation between maize crop development and growing season temperature. It determined that warming during the past three decades in Mozambique may be causing more frequent crop stress and yield reductions in that country's maize crop, independent of any changes occurring in rainfall. This report summarizes the findings and conclusions of that study.

  12. MUSIC for sub/millimeter astrophysics

    NASA Astrophysics Data System (ADS)

    Maloney, Philip R.; Czakon, Nicole G.; Day, Peter K.; Downes, Thomas P.; Duan, Ran; Gao, Jiansong; Glenn, Jason; Golwala, Sunil R.; Hollister, Matt I.; LeDuc, Henry G.; Mazin, Benjamin A.; McHugh, Sean G.; Noroozian, Omid; Nguyen, Hien T.; Sayers, Jack; Schlaerth, James A.; Siegel, Seth; Vaillancourt, John E.; Vayonakis, Anastasios; Wilson, Philip; Zmuidzinas, Jonas

    2010-07-01

    MUSIC (the Multiwavelength Submillimeter kinetic Inductance Camera) is an instrument being developed for the Caltech Submillimeter Observatory by Caltech, JPL, the University of Colorado, and UCSB. MUSIC uses microwave kinetic inductance detectors (MKIDs) - superconducting micro-resonators - as photon detectors. The readout is almost entirely at room temperature and is highly multiplexed. MUSIC will have 576 spatial pixels in four bands at 850, 1100, 1300 and 2000 microns. MUSIC is scheduled for deployment at the CSO in the winter of 2010/2011. We present an overview of the camera design and readout and describe the current status of the instrument and some results from the highly successful May/June 2010 observing run at the CSO with the prototype camera, which verified the performance of the complete system (optics, antennas/filters, resonators, and readout) and produced the first simultaneous 3-color observations with any MKID camera.

  13. Teaching Introductory Mineralogy With the GeoWall

    NASA Astrophysics Data System (ADS)

    Anderson, C. D.; Haymon, R. M.

    2003-12-01

    Mineralogy, like many topics in Earth Sciences, contains inherently three-dimensional topics that are difficult to teach. Concepts such as crystal symmetry and forms, Miller indices, the polymerization of silica tetrahedra and resulting structures of silicate mineral groups, and the interaction of light and minerals are particularly difficult. Two-dimensional diagrams are limited in their effectiveness, and physical models, while effective, are expensive and do not work as well in large class settings. The GeoWall system brings the effectiveness of physical models to the large classroom. In Fall 2003, we will integrate the GeoWall into our introductory mineralogy classes at UCSB using a combination of commercial software, atomic structure models available on the web, and custom content created in-house. The commercial software SHAPE (www.shapesoftware.com) allows users to build and display crystal shapes and their symmetry. Though not designed for the GeoWall, the software's stereopair display mode works perfectly on the system. Using the Chime web browser plug-in (www.mdl.com), computer models of silicate minerals available from the Virtual Museum of Minerals and Molecules (www.soils.umn.eduvirtual_museum) provide an interactive display of silicate mineral structure that illustrates the tetrahedral framework. Again, while not developed for the GeoWall, the Chime plug-in works seamlessly with the GeoWall hardware. 3-D GeoWall images that display light paths through minerals, and reveal relationships between crystal symmetry and optical indicatrix properties, have been developed in-house using a combination of SHAPE and 3D modeling software. The 3-D GeoWall images should convey in an instant these difficult concepts that students historically have struggled to visualize. Initial assessment of the GeoWall's effectiveness as a mineralogy teaching aid at UCSB in Fall 2003 will come from the instructor's impressions and by comparing test scores with classes from

  14. Dad's in the Garage: Santa Barbara Physicists in the Long 1970s

    NASA Astrophysics Data System (ADS)

    Mody, Cyrus

    2013-03-01

    American physicists faced many challenges in the 1970s: declining research budgets; public skepticism of scientific authority; declining student enrollments; and pressure to shift to topics such as biomedicine, environmental remediation, alternative energy, public housing and transport, and disability technologies. This paper examines the responses to these challenges of a small group of Santa Barbara physicists. While this group is not representative of the American physics profession, the success and failure of their responses to changed conditions tells us something about how American physicists got through the 1970s, and about the origins of some features of American physics today. The three physicists examined here are Philip Wyatt, David Phillips, and Virgil Elings. In the late `60s, Wyatt left a defense think tank to found an instrumentation firm. The Santa Barbara oil spill and other factors pushed that firm toward civilian markets in biomedicine and pollution measurement. Phillips joined Wyatt's firm from UCSB, while also founding his own company, largely to sell electronic devices for parapsychology. Phillips was also the junior partner in a master's of scientific instrumentation degree curriculum founded by Elings in order to save UCSB Physics' graduate program. Through the MSI program, Elings moved into biomedical research and became a serial entrepreneur. By the 1990s, Wyatt, Phillips, and Elings' turn toward academic entrepreneurship, dual military-civilian markets for physics start-ups, and interdisciplinary collaborations between physicists and life scientists were no longer unusual. Together, their journey through the `70s shows how varied the physics' profession's response to crisis was, and how much it pivoted on new interactions between university and industry.

  15. Cooperation Among Theorem Provers

    NASA Technical Reports Server (NTRS)

    Waldinger, Richard J.

    1998-01-01

    This is a final report, which supports NASA's PECSEE (Persistent Cognizant Software Engineering Environment) effort and complements the Kestrel Institute project "Inference System Integration via Logic Morphism". The ultimate purpose of the project is to develop a superior logical inference mechanism by combining the diverse abilities of multiple cooperating theorem provers. In many years of research, a number of powerful theorem-proving systems have arisen with differing capabilities and strengths. Resolution theorem provers (such as Kestrel's KITP or SRI's, SNARK) deal with first-order logic with equality but not the principle of mathematical induction. The Boyer-Moore theorem prover excels at proof by induction but cannot deal with full first-order logic. Both are highly automated but cannot accept user guidance easily. The PVS system (from SRI) in only automatic within decidable theories, but it has well-designed interactive capabilities: furthermore, it includes higher-order logic, not just first-order logic. The NuPRL system from Cornell University and the STeP system from Stanford University have facilities for constructive logic and temporal logic, respectively - both are interactive. It is often suggested - for example, in the anonymous "QED Manifesto"-that we should pool the resources of all these theorem provers into a single system, so that the strengths of one can compensate for the weaknesses of others, and so that effort will not be duplicated. However, there is no straightforward way of doing this, because each system relies on its own language and logic for its success. Thus. SNARK uses ordinary first-order logic with equality, PVS uses higher-order logic. and NuPRL uses constructive logic. The purpose of this project, and the companion project at Kestrel, has been to use the category-theoretic notion of logic morphism to combine systems with different logics and languages. Kestrel's SPECWARE system has been the vehicle for the implementation.

  16. γH2AX and p53 responses in TK6 cells discriminate promutagens and nongenotoxicants in the presence of rat liver S9.

    PubMed

    Bernacki, Derek T; Bryce, Steven M; Bemis, Jeffrey C; Kirkland, David; Dertinger, Stephen D

    2016-08-01

    Previous work with a diverse set of reference chemicals suggests that an in vitro multiplexed flow cytometry-based assay (MultiFlow™ DNA Damage Kit-p53, γH2AX, Phospho-Histone H3) can distinguish direct-acting clastogens and aneugens from nongenotoxicants (Bryce SM et al. []: Environ Mol Mutagen 57:171-189). This work extends this line of investigation to include compounds that require metabolic activation to form reactive electrophiles. For these experiments, TK6 cells were exposed to 11 promutagens and 37 presumed nongenotoxicants in 96 well plates. Unless precipitation or foreknowledge about cytotoxicity suggested otherwise, the highest concentration was 1 mM. Exposure occurred for 4 hr after which time cells were washed to remove S9 and test article. Immediately following the wash and again at 24 hr, cell aliquots were added to wells of a microtiter plate containing the working detergent/stain/antibody cocktail. After a brief incubation, robotic sampling was employed for walk-away flow cytometric data acquisition. Univariate logistic regression analyses indicated that γH2AX induction and p53 activation provide the greatest degree of discrimination between clastogens and nongenotoxicants. Multivariate prediction algorithms that incorporated both of these endpoints, in each combination of time points, were evaluated. The best performing models correctly predicted 9 clastogens out of 11 and 36 nongenotoxicants out of 37. These results are encouraging as they suggest that an efficient and highly scalable multiplexed assay can effectively identify clastogenic chemicals that require bioactivation. More work is planned with a broader range of chemicals, additional cell lines, and other laboratories to further evaluate the merits and limitations of this approach. Environ. Mol. Mutagen. 57:546-558, 2016. © 2016 Wiley Periodicals, Inc. PMID:27364561

  17. Effect of aspect-ratio on vortex distribution and heat transfer in rotating Rayleigh-Bénard convection

    NASA Astrophysics Data System (ADS)

    Overkamp, J.; Stevens, R. J. A. M.; Lohse, Detlef; Clercx, Herman J. H.

    2011-12-01

    Numerical and experimental data for the heat transfer as function of the Rossby number Ro in rotating Rayleigh-Benard are presented for Pr = 4.38 and up to Ra = 4.52 × 109 . The aspect ratio is varied between Γ = 0.5 and Γ = 2.0. Without rotation, where the aspect ratio influences the global flow structure, we see a small aspect-ratio dependence in the Nusselt number. For stronger rotation, i.e. 1/Ro gg 1/Roc, the heat transport becomes independent of the aspect-ratio. We interpret this finding as follows: In the rotating regime the heat is mainly transported by vertically-aligned vortices. Since these vortices are local, the aspect ratio has a negligible effect on the heat transport in the rotating regime. Indeed, an analysis of the vortex statistics shows that the fraction of the horizontal area that is covered by vortices is aspect-ratio independent when 1/Ro gg 1/Roc. In agreement with the results of Weiss & Ahlers (2011) we find a vortex-depleted area close to the sidewall. Here, we show that there is also an area with enhanced vortex concentration next to the vortex-depleted edge region and that the absolute widths of both regions are independent of the aspect ratio. This proceeding is a summary of Stevens et al. (2011).

  18. From Liquid Helium to Granular Materials

    NASA Astrophysics Data System (ADS)

    Behringer, Robert P.

    2016-11-01

    This article provides a brief history of work that I have either carried out with Horst Meyer, or that was connected in some way with experiences reaching back to the laboratory known as LTM for low temperature [physics] Meyer, at Duke University. It is not intended as a complete review of all relevant work, but rather to hit highlights. My work with Horst started with studies of critical phenomena in liquid helium. This system provided an extremely rich and diverse testing ground for then newly emerging theories of static and dynamic critical phenomena. A key aspect of the experimental work with Horst was high-precision measurements of temperature and pressure. The ability to measure thermal properties with exceptional precision was at the core of this work. It also provided a natural springboard for entirely different investigations of Rayleigh-Bénard convection, which had just been initiated by Guenter Ahlers. My postdoc with Guenter provided a whole new set of experiences involving convection, dynamical instabilities, and chaos, where again the special properties, measurement techniques, and creative approaches to research associated with liquid helium were critical. In fact, later, knowledge of these techniques allowed me to start a whole new research direction in granular materials, which is a primary focus of my current research.

  19. Large-scale-circulation dynamics of turbulent Rayleigh-Benard convection in a cubic container

    NASA Astrophysics Data System (ADS)

    Bai, Kunlun; Ji, Dandan; Brown, Eric

    2014-11-01

    We present measurements of the large-scale-circulation (LSC) in turbulent Rayleigh-Benard convection in a cubic container. The experiments cover the Rayleigh number ranging from 0 . 5 ×109 to 3 ×109 at Prandtl number 6.4. Using three rows of thermistors at different height of the container, the large-scale-circulation (LSC) can then be identified. It is found that the LSC prefers to lock at the corners of the container, and switches between them stochastically. The strength of LSC keeps as a constant during the switching which suggests those switching correspond to fluctuation driven crossings of a potential barrier in θ due to the side wall geometry as predicted by Brown and Ahlers (Phys. Fluids, 2008). The switching frequency is found to decrease as Ra increases. The measured LSC orientation and its switching will be compared to the model which predicts the effects of container geometry on large-scale coherent structure dynamics for arbitrary geometry.

  20. Accidental inflation from Kähler uplifting

    SciTech Connect

    Ben-Dayan, Ido; Westphal, Alexander; Wieck, Clemens; Jing, Shenglin E-mail: shenglin.jing@utoronto.ca E-mail: clemens.wieck@desy.de

    2014-03-01

    We analyze the possibility of realizing inflation with a subsequent dS vacuum in the Käahler uplifting scenario. The inclusion of several quantum corrections to the 4d effective action evades previous no-go theorems and allows for construction of simple and successful models of string inflation. The predictions of several benchmark models are in accord with current observations, i.e., a red spectral index, negligible non-gaussianity, and spectral distortions similar to the simplest models of inflation. A particularly interesting subclass of models are ''left-rolling'' ones, where the overall volume of the compactified dimensions shrinks during inflation. We call this phenomenon ''inflation by deflation'' (IBD), where deflation refers to the internal manifold. This subclass has the appealing features of being insensitive to initial conditions, avoiding the overshooting problem, and allowing for observable running α ∼ 0.012 and enhanced tensor-to-scalar ratio r ∼ 10{sup −5}. The latter results differ significantly from many string inflation models.

  1. Using Earth Data in an Introductory Oceanography Course

    NASA Astrophysics Data System (ADS)

    Prothero, W. A.

    2002-12-01

    Activities that engage students in the use and interpretation of real earth data provide an effective way of promoting an understanding of the science process. In UCSB's introductory Oceanography course, major goals are to improve student understanding of how science works and how to interpret science claims in the popular media. Activities are modeled after those of practicing scientists. These include: a) posing a solvable problem, b) choosing and acquiring relevant data, c) describing the data, d) interpreting the data, e) giving talks to peers, and f) publishing and reviewing findings. Each of these activities poses pedagogical challenges that must be addressed in carefully sequenced course assignments that build upon each other, and respond to a variety of learning styles. The use of earth data in education also presents significant challenges in creating effective data acquisition and display tools. However, only item b, above, is pertinent to these tools. The other items present similar challenges. During the course, learners must acquire enough subject knowledge to successfully interpret the data. They must understand the theory or model they are testing, how the relevant data can be used to test the model, and how to illustrate and present their findings orally and in writing. Some of the assignments that support this are: online homework, online subject area mini-quizzes (randomly created from a database of questions), "questions of the day" in lecture, online short answer thought questions, lab section guided mini-investigations, lab section group presentations, short writing exercises, and 2 longer writing assignments. Students rate the writing assignments as the most effective course component that contributes to their learning. The writing assignments focus student effort and also produce a product that we can study in an attempt to measure student learning. Prof. Gregory Kelly and Prof. Charles Bazerman (UCSB Graduate School of Education) are

  2. Land Surface Modeling Applications for Famine Early Warning

    NASA Astrophysics Data System (ADS)

    McNally, A.; Verdin, J. P.; Peters-Lidard, C. D.; Arsenault, K. R.; Wang, S.; Kumar, S.; Shukla, S.; Funk, C. C.; Pervez, M. S.; Fall, G. M.; Karsten, L. R.

    2015-12-01

    AGU 2015 Fall Meeting Session ID#: 7598 Remote Sensing Applications for Water Resources Management Land Surface Modeling Applications for Famine Early Warning James Verdin, USGS EROS Christa Peters-Lidard, NASA GSFC Amy McNally, NASA GSFC, UMD/ESSIC Kristi Arsenault, NASA GSFC, SAIC Shugong Wang, NASA GSFC, SAIC Sujay Kumar, NASA GSFC, SAIC Shrad Shukla, UCSB Chris Funk, USGS EROS Greg Fall, NOAA Logan Karsten, NOAA, UCAR Famine early warning has traditionally required close monitoring of agro-climatological conditions, putting them in historical context, and projecting them forward to anticipate end-of-season outcomes. In recent years, it has become necessary to factor in the effects of a changing climate as well. There has also been a growing appreciation of the linkage between food security and water availability. In 2009, Famine Early Warning Systems Network (FEWS NET) science partners began developing land surface modeling (LSM) applications to address these needs. With support from the NASA Applied Sciences Program, an instance of the Land Information System (LIS) was developed to specifically support FEWS NET. A simple crop water balance model (GeoWRSI) traditionally used by FEWS NET took its place alongside the Noah land surface model and the latest version of the Variable Infiltration Capacity (VIC) model, and LIS data readers were developed for FEWS NET precipitation forcings (NOAA's RFE and USGS/UCSB's CHIRPS). The resulting system was successfully used to monitor and project soil moisture conditions in the Horn of Africa, foretelling poor crop outcomes in the OND 2013 and MAM 2014 seasons. In parallel, NOAA created another instance of LIS to monitor snow water resources in Afghanistan, which are an early indicator of water availability for irrigation and crop production. These successes have been followed by investment in LSM implementations to track and project water availability in Sub-Saharan Africa and Yemen, work that is now underway. Adoption of

  3. The Bermuda BioOptics Project (BBOP) Years 9-11

    NASA Technical Reports Server (NTRS)

    Nelson, Norm

    2003-01-01

    The Bermuda BioOptics Project (BBOP) is a collaborative effort between the Institute for Computational Earth System Science (ICESS) at the University of California at Santa Barbara (UCSB) and the Bermuda Biological Station for Research (BBSR). This research program is designed to characterize light availability and utilization in the Sargasso Sea, and to provide an optical link by which biogeochemical observations may be used to evaluate bio-optical models for pigment concentration, primary production, and sinking particle fluxes from satellite-based ocean color sensors. The BBOP time-series was initiated in 1992, and is carried out in conjunction with the U.S. JGOFS Bermuda Atlantic Time-series Study (BATS) at the Bermuda Biological Station for Research. The BATS program itself has been observing biogeochemical processes (primary productivity, particle flux and elemental cycles) in the mesotrophic waters of the Sargasso Sea since 1988. Closely affiliated with BBOP and BATS is a separate NASA-funded study of the spatial variability of biogeochemical processes in the Sargasso Sea using high-resolution AVHRR and SeaWiFS data collected at Bermuda. The collaboration between BATS and BBOP measurements has resulted in a unique data set that addresses not only the SIMBIOS goals but also the broader issues of important factors controlling the carbon cycle. This final report addresses specific research activities, research results, and lists of presentations and papers submitted for publication.

  4. The Background Emission Anisotropy Scanning Telescope (BEAST)

    NASA Astrophysics Data System (ADS)

    Seiffert, M.

    1996-12-01

    Since 1988 the UCSB Cosmology Group has performed a number of measurements of the degree scale structure in the Cosmic Background Radiation. These include 3 South Pole expeditions in 1989, 91 and 94. and 8 balloon flights using SIS, HEMTs and bolometer based detectors. We will present a summary of these measurements focusing onthe recent results. In addition, we will describe the recent flight of HACME, a balloon- borne experiment to map CMB anisotropies with 0.75 degree angular resolution over several hundred square degrees. This experiment is a prototype for our next generation CMB experiment, the Background Emission Anisotropy Scanning Telescope (BEAST). BEAST will feature a 2 m diameter carbon fiber composite primary mirror for high angular resolution and a sensitive array of ultra-low noise HEMT amplifiers at 30, 40, and 90 GHz. BEAST is designed for an Antarctic long duration balloon flight allowing an observing time of order two weeks. This experiment will provide an unprecedented combination of sensitivty and angular resolution across a significant region of sky.

  5. T-shaped emitter metal heterojunction bipolar transistors for submillimeter wave applications

    NASA Technical Reports Server (NTRS)

    Fung, Andy; Samoska, Lorene; Velebir, Jim; Siege, Peter; Rodwell, Mark; Paidi, Vamsi; Griffth, Zach; Urteaga, Miguel; Malik, Roger

    2004-01-01

    We report on the development of submillimeter wave transistors at JPL. The goal of the effort is to produce advance-reliable high frequency and high power amplifiers, voltage controlled oscillators, active multipliers, and high-speed mixed-signal circuits for space borne applications. The technology in development to achieve this is based on the Indium Phosphide (InP) Heterojunction Bipolar Transistor (HBT). The HBT is well suited for high speed, high power and uniform (across wafer) performance, due to the ability to tailor the material structure that electrons traverse through by well-controlled epitaxial growth methods. InP with its compatible lattice matched alloys such as indium gallium arsenide (InGaAs) and indium aluminium arsenide (InAlAs) provides for high electron velocities and high voltage breakdown capabilities. The epitaxial methods for this material system are fairly mature, however the implementation of high performance and reliable transistors are still under development by many laboratories. Our most recently fabricated, second generation mesa HBTs at JPL have extrapolated current gain cutoff frequency (FJ of 142GHz and power gain cutoff frequency (Fm,) of approximately 160GHz. This represents a 13% and 33% improvement of Ft and F, respectively, compared to the first generation mesa HBTs [l]. Analysis based on the University of California, Santa Barbara (UCSB) device model, RF device characteristics can be significantly improved by reducing base contact resistance and base metal contact width. We will describe our effort towards increasing transistor performance and yield.

  6. Integrating observation and statistical forecasts over sub-Saharan Africa to support Famine Early Warning

    USGS Publications Warehouse

    Funk, C.; Verdin, J.P.; Husak, G.

    2007-01-01

    Famine early warning in Africa presents unique challenges and rewards. Hydrologic extremes must be tracked and anticipated over complex and changing climate regimes. The successful anticipation and interpretation of hydrologic shocks can initiate effective government response, saving lives and softening the impacts of droughts and floods. While both monitoring and forecast technologies continue to advance, discontinuities between monitoring and forecast systems inhibit effective decision making. Monitoring systems typically rely on high resolution satellite remote-sensed normalized difference vegetation index (NDVI) and rainfall imagery. Forecast systems provide information on a variety of scales and formats. Non-meteorologists are often unable or unwilling to connect the dots between these disparate sources of information. To mitigate these problem researchers at UCSB's Climate Hazard Group, NASA GIMMS and USGS/EROS are implementing a NASA-funded integrated decision support system that combines the monitoring of precipitation and NDVI with statistical one-to-three month forecasts. We present the monitoring/forecast system, assess its accuracy, and demonstrate its application in food insecure sub-Saharan Africa.

  7. Aesthetic Physics Education: A Symmetry Based, Physics and Fine Arts Curriculum

    NASA Astrophysics Data System (ADS)

    van der Veen, Jatila; Lubin, P. M.; Cook-Gumperz, J.; Raley, J. D.; Mazur, E.

    2006-12-01

    Physics education research in the past two decades has focused almost entirely on pedagogical methods, but the curriculum content remains unchanged. In a recent editorial in Physics Today (July, 2006, p. 10) the ability of physicists to “imagine new realities” is correlated with what are traditionally considered non-scientific skills, including imagination and creativity, qualities which are usually associated with fine arts. In view of the new developments in physics of the 21st Century, the importance of developing creativity and imagination through education is gaining recognition. We are investigating the effectiveness of teaching introductory physics from the viewpoint of symmetry, including the foundations of General Relativity and modern cosmology, without the need for the full tensor treatment. We will pilot a new course at UCSB in Winter Quarter, 2007 entitled Symmetry and Aesthetics in Introductory Physics. Our pedagogical model is based on three premises: that the introductory curriculum needs to be modernized; that mathematics should be presented as a language; and that theoretical physics has, at its core, a great deal in common with music, art, and dance. In this talk we will present the contents of our new course, and the means by which we plan to evaluate it in comparison to “regular” introductory courses. It is our hope that this modernized and integrated approach to introductory physics can also serve as a course for future teachers of primary and secondary school. This work is supported by NASA grant #20070268 and the Planck Explorer Mission.

  8. Aerosol Characterization and New Instrumentation for Better Understanding Snow Radiative Properties

    NASA Astrophysics Data System (ADS)

    Beres, N. D.

    2015-12-01

    Snow albedo is determined by snowpack thickness and grain size, but also affected by contamination with light-absorbing, microscopic (e.g., mineral dust, combustion aerosols, bio-aerosols) and macroscopic (e.g., microalgae, plant debris, sand, organisms) compounds. Most currently available instruments for measuring snow albedo utilize the natural, downward flux of solar radiation and the reflected upward flux. This reliance on solar radiation (and, thus, large zenith angles and clear-sky conditions) leads to severe constraints, preventing characterization of detailed diurnal snow albedo cycles. Here, we describe instrumentation and methodologies to address these limitations with the development and deployment of new snow radiation sensors for measuring surface spectral and in-snow radiative properties. This novel instrumentation will be tested at the CRREL/UCSB Eastern Sierra (CUES) Snow Study Site at Mammoth Mountain, which is extensively instrumented for characterizing snow properties including snow albedo and surface morphology. However, it has been lacking instrumentation for the characterization of aerosols that can be deposited on the snow surface through dry and wet deposition. Currently, we are installing aerosol instrumentation at the CUES site, which are also described. This includes instruments for the multi-wavelength measurement of aerosol scattering and absorption coefficients and for the characterization of aerosol size distribution. Knowledge of aerosol concentration and physical and optical properties will allow for the study of aerosol deposition and modification of snow albedo and for establishing an aerosol climatology for the CUES site.

  9. Hybrid silicon free-space source with integrated beam steering

    NASA Astrophysics Data System (ADS)

    Doylend, J. K.; Heck, M. J. R.; Bovington, J. T.; Peters, J. D.; Davenport, M. L.; Coldren, L. A.; Bowers, J. E.

    2013-02-01

    Free-space beam steering using optical phase arrays are desirable as a means of implementing Light Detection and Ranging (LIDAR) and free-space communication links without the need for moving parts, thus alleviating vulnerabilities due to vibrations and inertial forces. Implementing such an approach in silicon photonic integrated circuits is particularly desirable in order to take advantage of established CMOS processing techniques while reducing both device size and packaging complexity. In this work we demonstrate a free-space diode laser together with beam steering implemented on-chip in a silicon photonic circuit. A waveguide phased array, surface gratings, a hybrid III-V/silicon laser and an array of hybrid III/V silicon amplifiers were fabricated on-chip in order to achieve a fully integrated steerable free-space optical source with no external optical inputs, thus eliminating the need for fiber coupling altogether. The chip was fabricated using a modified version of the hybrid silicon process developed at UCSB, with modifications in order to incorporate diodes within the waveguide layer as well as within the III-V gain layer. Beam steering across a 12° field of view with +/-0.3° accuracy and 1.8°x0.6° beam width was achieved, with background peaks suppressed 7 dB relative to the main lobe within the field of view for arbitrarily chosen beam directions.

  10. Influence of phonon emission on intersubband lifetimes in wide GaAs/AlGaAs and Si/SiGe quantum wells

    SciTech Connect

    Murdin, B.N.; Pidgeon, C.R.; Lee, S.C.

    1995-12-31

    We have previously used the picosecond far-infrared free electron laser FELIX, at Rijnhuizen, to make the first direct excite-probe determination of the intersubband relaxation rate in wide GaAs/AlGaAs quantum wells with the subband separation smaller than the optical phonon energy. This measurement yielded short (40ps) lifetimes while acoustic phonon emission occurs on a 200ps scale. This is also in contrast with, among others, saturation measurements of swide wells with the UCSB FEL which gave lifetimes of 600ps. We discuss here the interpretation of the range of published results by calculation of the LO-phonon scattering rate, including the effects of finite electron temperature, T{sub e}. We have shown that relaxation can be dominated by LO-phonon emission even in wide wells, through the high energy tail of the distribution. The rate is very sensitive to T{sub e} between 30-70K, and also to carrier concentration, making it possible to account for the wide variety of published results with a single mechanism. We have extended our measurements to wide Si/SiGe quantum Wells, and find similarly short times (20-30ps). However, in non-polar materials such as SiGe the deformation potential scattering is much weaker and acoustic phonon emission (order 10ps in n-silicon) is expected to dominate.

  11. Cosmic microwave background anisotropies in cold dark matter models with cosmological constant: The intermediate versus large angular scales

    NASA Technical Reports Server (NTRS)

    Stompor, Radoslaw; Gorski, Krzysztof M.

    1994-01-01

    We obtain predictions for cosmic microwave background anisotropies at angular scales near 1 deg in the context of cold dark matter models with a nonzero cosmological constant, normalized to the Cosmic Background Explorer (COBE) Differential Microwave Radiometer (DMR) detection. The results are compared to those computed in the matter-dominated models. We show that the coherence length of the Cosmic Microwave Background (CMB) anisotropy is almost insensitive to cosmological parameters, and the rms amplitude of the anisotropy increases moderately with decreasing total matter density, while being most sensitive to the baryon abundance. We apply these results in the statistical analysis of the published data from the UCSB South Pole (SP) experiment (Gaier et al. 1992; Schuster et al. 1993). We reject most of the Cold Dark Matter (CDM)-Lambda models at the 95% confidence level when both SP scans are simulated together (although the combined data set renders less stringent limits than the Gaier et al. data alone). However, the Schuster et al. data considered alone as well as the results of some other recent experiments (MAX, MSAM, Saskatoon), suggest that typical temperature fluctuations on degree scales may be larger than is indicated by the Gaier et al. scan. If so, CDM-Lambda models may indeed provide, from a point of view of CMB anisotropies, an acceptable alternative to flat CDM models.

  12. Estimation of broadband surface emissivity from narrowband emissivities.

    PubMed

    Tang, Bo-Hui; Wu, Hua; Li, Chuanrong; Li, Zhao-Liang

    2011-01-01

    This work analyzed and addressed the estimate of the broadband emissivities for the spectral domains 3-14μm (ε(3-14)) and 3-∞μm (ε(3-∞). Two linear narrow-to-broadband conversion models were proposed to estimate broadband emissivities ε(3-14) and ε(3-∞) using the Moderate Resolution Imaging Spectroradiometer (MODIS) derived emissivities in three thermal infrared channels 29 (8.4-8.7μm), 31 (10.78-11.28μm) and 32 (11.77-12.27μm). Two independent spectral libraries, the Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) spectral library and the MODIS UCSB (University of California, Santa Barbara) emissivity library, were used to calibrate and validate the proposed models. Comparisons of the estimated broadband emissivities using the proposed models and the calculated values from the spectral libraries, showed that the proposed method of estimation of broadband emissivity has potential accuracy and the Root Mean Square Error (RMSE) between estimated and calculated broadband emissivities is less than 0.01 for both ε(3-14) and ε(3-∞).

  13. Interaction of highly vibrationally excited molecules with clean metal surfaces. Final technical report

    SciTech Connect

    Wodtke, A.M.; Auerbach, D.J.

    1998-11-01

    The authors present results from a grant funded under the Department of Energy Office of Basic Energy Sciences. A collaboration between Prof. Alec Wodtke of the Department of Chemistry at UCSB and Daniel J. Auerbach of IBM Almaden Research Labs has allowed new experiments on the dynamics of surface chemical reactivity to be successfully executed. High quality data has been generated which provides an excellent test of theoretical models of surface reactivity, a topic of importance to catalysis. The authors have obtained the first experimental measurements on the influence of reactant velocity on the steric effect in a chemical reaction: the dissociative adsorption of hydrogen on copper. They have also designed and built a molecular beam scattering apparatus for the study of highly vibrationally excited molecules and their interactions with clean and oxidized metal surfaces. With this apparatus they have observed the vibrational energy exchange of highly vibrationally excited NO with an oxidized copper surface. Multi-quantum vibrational relaxation was found ({Delta}v = 1-5). Such remarkably strong and efficient vibrational energy transfer represents a qualitatively new phenomenon and is representative of the exciting new behavior that they had hoped might be observable in this project. Evidence of chemical reactivity of vibrationally excited NO on a clean copper surface was also found.

  14. FINAL TECHNICAL REPORT to the DOE NABIR PROGRAM

    SciTech Connect

    Holden, Patricia A

    2009-08-31

    This project was funded to Dr. Mary Neu (LANL) and to Dr. Patricia Holden (UCSB) during the period 10/01/04-09/30/07 with the overall objective of, as stated in the proposal, to investigate how key reactions, which are known to affect major redox-active transition metals such as Fe and Mn, can affect Pu speciation and environmental mobility. The goals included investigating a) bacterial accumulation and immobilization of Pu species by Pseudomonas putida biofilm formation, and b) bacterial mineralization and immobilization via direct enzymatic and indirect biogeochemical reduction of Pu species by Geobacter metallireducens. Through a combination of aqueous chemical, radioanalytical, spectroscopic and microscopic analyses, Pu speciation and solution/solid phase distributions were to be characterized. The combination of biotransformation and biogeochemical research was aimed at filling significant gaps in the scientific basis for monitored natural attenuation and in situ stabilization of widespread and problematic Pu contamination, as well as providing immediately useful data to modeling and risk assessment efforts.

  15. Quantum State Tomography of a Cooper-pair Box

    NASA Astrophysics Data System (ADS)

    Novikov, Sergey; Zaretskey, V.; Suri, B.; Kim, Z.; Palmer, B. S.; Wellstood, F. C.

    2011-03-01

    A 4-8 GHz microwave pulse shaping system with 3 ns Gaussian pulse rise time, arbitrary pulse envelope and phase control has been implemented. The system utilizes a two-channel 1 GSa/s DAC board to supply control voltages to an IQ mixer. The signals to the mixer have been optimized to obtain an on-off ratio of > 85 dB and phase deviations < 5 % . The setup has been used to manipulate an Al /AlOx / Al Cooper-pair box (CPB) qubit coupled to a lumped-element microwave resonator (f0 = 5 . 446 GHz). The CPB has a charging energy EC / h = 6 . 25 GHz and a maximum EJ / h = 19 GHz which was decreased to an effective EJ / h = 6 . 1 GHz by an external magnetic field. By measuring the microwave transmission at f0 in a pulsed-probe scheme, we perform a dispersive readout of the qubit. We present tomography data on the | g > , | e > , (| g > + | e >) /√{ 2 } and (| g > + i | e >) /√{ 2 } states. We find good agreement with theory, confirming that we have achieved the desired microwave pulse control. Designed by J. Martinis at UCSB and fabricated by HSCC.

  16. HIGH-EFFICIENCY NITRIDE-BASED SOLID-STATE LIGHTING

    SciTech Connect

    Dr. Paul T. Fini; Prof. Shuji Nakamura

    2002-04-30

    In this semiannual report we summarize the progress obtained in the first six months with the support of DoE contract No.DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. The two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and Rensselaer Polytechnic Institute (led by Dr. N. Narendran), are pursuing the goals of this contract from thin film growth, characterization, and packaging standpoints. The UCSB team has made significant progress in the development of GaN vertical cavity surface-emitting lasers (VCSELs) as well as light-emitting diodes (LEDs) with AlGaN active regions emitting in the ultraviolet (UV). The Rensselaer team has developed target specifications for some of the key parameters for the proposed solid-state lighting system, including a luminous flux requirement matrix for various lighting applications, optimal spectral power distributions, and the performance characteristics of currently available commercial LEDs for eventual comparisons to the devices developed in the scope of this project.

  17. CMB Anisotropies Two Years after Cobe: Observations, Theory and the Future - Proceedings of the 1994 Cwru Workshop

    NASA Astrophysics Data System (ADS)

    Krauss, Lawrence M.

    1995-01-01

    The Table of Contents for the book is as follows: * Preface * I. The Experimental Situation Two Years After COBE: Anisotropies, and the CMB Power Spectrum * COBE DMR Data, Signal and Noise: Color Plates * CMB Two Years After the COBE Discovery of Anisotropies * Comparison of Spectral Index Determinations * Two-Point Correlations in the COBE-DMR Two-Year Anisotropy Maps * A Preliminary Analysis of UCSB's South Pole 1993-94 Results * CMB Anisotropy Measurements During the Fourth Flight of MAX * Observations of the Anisotropy in the Cosmic Microwave Background by the Firs, SK93, and MSAM-I Experiments * The Python Microwave Background Anisotropy Experiment * II. Theoretical Implications and Cosmology: The Early Universe, Large Scale Structure and Dark Matter * Testing Inflationary Cosmology and Measuring Cosmological Parameters Using the Cosmic Microwave Background * Inflation Confronts the CMB: An Analysis Including the Effects of Foreground * Testing Inflation with MSAM, MAX Tenerife and COBE * CMBR Anisotropy Due to Gravitational Radiation in Inflationary Cosmologies * Black Holes From Blue Spectra * Cosmic Microwave Background Anisotropies and the Geometry of the Universe * Ω and Cosmic Microwave Background Anisotropies * CDM Cosmogony in an Open Universe * Cosmic Microwave Background Radiation Anisotropy Induced by Cosmic Strings * Temperature Anisotropies in a Universe with Global Defects * The Nature Versus Nurture of Anisotropies * The Existence of Baryons at z = 1000 * Polarization-Temperature Correlations in the Microwave Background * III. Related Issues: BBN Limits on ΩB, and Comparing Theoretical Predictions and Observations * Big Bang Nucleosynthesis and ΩB: A Guide for CMB Interpreters * Quoting Experimental Information

  18. FCRD Milestone Report: M21AF050901

    SciTech Connect

    Hoelzer, David T; Sokolov, Mikhail A; Byun, Thak Sang; Odette, George R.; Klingensmith, Doug; Gragg, David; Stergar, Eric; Fields, Kirk

    2011-09-01

    The objective of this study was to perform mechanical testing on large scale heats of the advanced ODS 14YWT alloy to investigate the effects of processing parameters on mechanical properties. Mechanical properties tests were conducted on two heats of the advanced ODS 14YWT ferritic alloy: the 14YWT-SM11 was produced by extrusion at ORNL and OW4 was produced by HIP at UCSB. The 14YWT-SM11 showed very high tensile strength compared to OW4, but showed less ductility as a result. The fracture toughness transition temperature of 14YWT-SM11 was determined in two orientations and showed T{sub 0} = 48 C in the favorably strong L-T direction while shifting by 63 C to T{sub 0} = 111 C in the weaker T-L direction. The fracture toughness transition temperature for OW4 was not determined but appeared to be within the range observed for 14YWT-SM11. The fracture toughness of 14YWT-SM11 at room temperature was 86.8 MPa{radical}m and 93.1 MPa{radical}m, which was much higher than that of OW4 (27.4 MPa{radical}m). The strain rate jump tests conducted on OW4 indicated that the creep properties were similar to MA957 at 750 C.

  19. Bermuda Bio Optics Project. Chapter 14

    NASA Technical Reports Server (NTRS)

    Nelson, Norm

    2003-01-01

    The Bermuda BioOptics Project (BBOP) is a collaborative effort between the Institute for Computational Earth System Science (ICESS) at the University of California at Santa Barbara (UCSB) and the Bermuda Biological Station for Research (BBSR). This research program is designed to characterize light availability and utilization in the Sargasso Sea, and to provide an optical link by which biogeochemical observations may be used to evaluate bio-optical models for pigment concentration, primary production, and sinking particle fluxes from satellite-based ocean color sensors. The BBOP time-series was initiated in 1992, and is carried out in conjunction with the U.S. JGOFS Bermuda Atlantic Time-series Study (BATS) at the Bermuda Biological Station for Research. The BATS program itself has been observing biogeochemical processes (primary productivity, particle flux and elemental cycles) in the mesotrophic waters of the Sargasso Sea since 1988. Closely affiliated with BBOP and BATS is a separate NASA-funded study of the spatial variability of biogeochemical processes in the Sargasso Sea using high-resolution AVHRR and SeaWiFS data collected at Bermuda (N. Nelson, P.I.). The collaboration between BATS and BBOP measurements has resulted in a unique data set that addresses not only the SIMBIOS goals but also the broader issues of important factors controlling the carbon cycle.

  20. The Bermuda BioOptics Project (BBOP) Years 9-11

    NASA Technical Reports Server (NTRS)

    Maritorena, S.; Siegel, D. A.; Nelson, Norm B.

    2004-01-01

    The Bermuda BioOptics Project (BBOP) is a collaborative effort between the Institute for Computational Earth System Science (ICESS) at the University of California at Santa Barbara (UCSB) and the Bermuda Biological Station for Research (BBSR). This research program is designed to characterize light availability and utilization in the Sargasso Sea, and to provide an optical link by which biogeochemical observations may be used to evaluate bio-optical models for pigment concentration, primary production, and sinking particle fluxes from satellite-based ocean color sensors. The BBOP time-series was initiated in 1992, and is carried out in conjunction with the U.S. JGOFS Bermuda Atlantic Time-series Study (BATS) at the Bermuda Biological Station for Research. The BATS program itself has been observing biogeochemical processes (primary productivity, particle flux and elemental cycles) in the mesotrophic waters of the Sargasso Sea since 1988. Closely affiliated with BBOP and BATS is a separate NASA-funded study of the spatial variability of biogeochemical processes in the Sargasso Sea using high-resolution AVHRR and SeaWiFS data collected at Bermuda. The collaboration between BATS and BBOP measurements has resulted in a unique data set that addresses not only the SIMBIOS goals but also the broader issues of important factors controlling the carbon cycle.

  1. The Bermuda Bio-Optics Program (BBOP). Chapter 16

    NASA Technical Reports Server (NTRS)

    Siegel, David A.

    2001-01-01

    The Bermuda Bio-Optics Project (BBOP) is a collaborative effort between the Institute for Computational Earth System Science (ICESS) at the University of California at Santa Barbara (UCSB) and the Bermuda Biological Station for Research (BBSR). This research program is designed to characterize light availability and utilization in the Sargasso Sea, and to provide an optical link by which biogeochemical observations may be used to evaluate bio-optical models for pigment concentration, primary production, and sinking particle fluxes from satellite-based ocean color sensors. The BBOP time-series was initiated in 1992, and is carried out in conjunction with the US JGOFS Bermuda Atlantic Time-series Study (BATS) at the Bermuda Biological Station for Research. The BATS program itself has been observing biogeochemical processes (primary productivity, particle flux at and elemental cycles) in the mesotrophic waters of the Sargasso Sea since 1988. Closely affiliated with BBOP and BATS is a separate NASA-funded study of the spatial variability of biogeochemical processes in the Sargasso Sea using high-resolution Advanced Very High Resolution Radiometer (AVHRR) and Sea-Viewing Wide Field-of-view Sensor (SeaWiFS) data collected at Bermuda. The collaboration between BATS and BBOP measurements has resulted in a unique data set that addresses not only the SIMBIOS goals but also the broader issues of important factors controlling the carbon cycle.

  2. Unique stability of neutral interstitial hydrogen in cubic BN and diamond

    NASA Astrophysics Data System (ADS)

    Lyons, John L.; van de Walle, Chris G.

    In virtually all semiconductors and insulators, hydrogen interstitial impurities act as negative-U centers, implying that hydrogen is never stable in the neutral charge state. Using hybrid density functional calculations, which are crucial for obtaining accurate properties of defects in semiconductors, we find a different behavior for hydrogen interstitials in diamond and cubic BN. In diamond, we find that hydrogen is a very strong positive-U center, and the neutral charge state of the interstitial is stable over a Fermi-level range of more than 2 eV. In cubic BN, a III-V compound semiconductor with properties similar to diamond, we also find positive-U behavior, though over a much smaller Fermi-level range. We will discuss the electronic-structure origins of this negative-U behavior, and compare with the properties of hydrogen in other materials. Research done in part at the Center for Functional Nanomaterials, which is a U.S. DOE Office of Science Facility, at Brookhaven National Laboratory under Contract No. DE-SC0012704. Work at UCSB was supported by the National Science Foundation.

  3. HIGH-EFFICIENCY NITRIDE-BASED SOLID-STATE LIGHTING

    SciTech Connect

    Paul T. Fini; Shuji Nakamura

    2003-10-30

    In this second annual report we summarize the progress in the second-year period of Department of Energy contract DE-FC26-01NT41203, entitled ''High- Efficiency Nitride-Based Solid-State Lighting''. The two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and Rensselaer Polytechnic Institute (led by Dr. N. Narendran), are pursuing the goals of this contract from thin film growth, characterization, and packaging standpoints. The UCSB team has recently made significant progress in the development of light-emitting diodes (LEDs) with AlGaN active regions emitting in the ultraviolet (UV), resonant-cavity LEDs (RCLEDs), as well as lateral epitaxial overgrowth (LEO) techniques to obtain large-area non-polar GaN films with low average dislocation density. The Rensselaer team has benchmarked the performance of commercially available LED systems and has also conducted efforts to develop an optimized RCLED packaging scheme, including development of advanced epoxy encapsulant chemistries.

  4. ARCHONS: a highly multiplexed superconducting optical to near-IR camera

    NASA Astrophysics Data System (ADS)

    Mazin, Benjamin A.; O'Brien, Kieran; McHugh, Sean; Bumble, Bruce; Moore, David; Golwala, Sunil; Zmuidzinas, Jonas

    2010-07-01

    We report on the development of ARCONS, the ARray Camera for Optical to Near-IR Spectrophotometry. This photon counting integral field unit (IFU), being built at UCSB and Caltech with detectors fabricated at JPL, will use a unique, highly multiplexed low temperature detector technology known as Microwave Kinetic Inductance Detectors (MKIDs). These detectors, which operate at 100 mK, should provide photon counting with energy resolution of R = E/δE > 20 and time resolution of a microsecond, with a quantum efficiency of around 50%. We expect to field the instrument at the Palomar 200" telescope in the first quarter of 2011 with an array containing 1024 pixels in a 32×32 pixel form factor to yield a field of view of approximately 10×10 arcseconds. The bandwidth of the camera is limited by the rising sky count rate at longer wavelengths, but we anticipate a bandwidth of 0.35 to 1.35 μm will be achievable. A simple optical path and compact dewar utilizing a cryogen-free adiabatic demagnetization refridgerator (ADR) allows the camera to be deployed quickly at Naysmith or Coudé foci at a variety of telescopes. A highly expandable software defined radio (SDR) readout that can scale up to much larger arrays has been developed.

  5. HIGH-EFFICIENCY NITRIDE-BASED SOLID-STATE LIGHTING

    SciTech Connect

    Dr. Paul T. Fini; Prof. Shuji Nakamura

    2002-09-01

    In this annual report we summarize the progress obtained in the first year with the support of DoE contract No.DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. The two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and Rensselaer Polytechnic Institute (led by Dr. N. Narendran), are pursuing the goals of this contract from thin film growth, characterization, and packaging standpoints. The UCSB team has made significant progress in the development of GaN vertical cavity surface-emitting lasers (VCSELs) as well as light-emitting diodes (LEDs) with AlGaN active regions emitting in the ultraviolet (UV). The Rensselaer team has developed target specifications for some of the key parameters for the proposed solid-state lighting system, including a luminous flux requirement matrix for various lighting applications, optimal spectral power distributions, and the performance characteristics of currently available commercial LEDs for eventual comparisons to the devices developed in the scope of this project.

  6. Tools for Implementing Science Practice in a Large Introductory Class

    NASA Astrophysics Data System (ADS)

    Prothero, W. A.

    2008-12-01

    Scientists must have in-depth background knowledge of their subject area and know where current knowledge can be advanced. They perform experiments that gather data to test new or existing theories, present their findings at meetings, publish their results, critically review the results of others, and respond to the reviews of their own work. In the context of a course, these activities correspond to learning the background material by listening to lectures or reading a text, formulating a problem, exploring data using student friendly data access and plotting software, giving brief talks to classmates in a small class or lab setting, writing a science paper or lab report, reviewing the writing of their peers, and receiving feedback (and grades) from their instructors and/or peers. These activities can be supported using course management software and online resources. The "LearningWithData" software system allows solid Earth (focused on plate tectonics) data exploration and plotting. Ocean data access, display, and plotting are also supported. Background material is delivered using animations and slide show type displays. Students are accountable for their learning through included homework assignments. Lab and small group activities provide support for data exploration and interpretation. Writing is most efficiently implemented using the "Calibrated Peer Review" method. This methodology is available at http://cpr.molsci.ucla.edu/. These methods have been successfully implemented in a large oceanography class at UCSB.

  7. Breakdown of the large-scale circulation in Γ=1/2 rotating Rayleigh-Bénard flow

    NASA Astrophysics Data System (ADS)

    Stevens, Richard J. A. M.; Clercx, Herman J. H.; Lohse, Detlef

    2012-11-01

    Experiments and simulations of rotating Rayleigh-Bénard convection in cylindrical samples have revealed an increase in heat transport with increasing rotation rate. This heat transport enhancement is intimately related to a transition in the turbulent flow structure from a regime dominated by a large-scale circulation (LSC), consisting of a single convection roll, at no or weak rotation to a regime dominated by vertically aligned vortices at strong rotation. For a sample with an aspect ratio Γ=D/L=1 (D is the sample diameter and L is its height) the transition between the two regimes is indicated by a strong decrease in the LSC strength. In contrast, for Γ=1/2, Weiss and Ahlers [J. Fluid Mech.JFLSA70022-112010.1017/jfm.2011.392 688, 461 (2011)] revealed the presence of a LSC-like sidewall temperature signature beyond the critical rotation rate. They suggested that this might be due to the formation of a two-vortex state, in which one vortex extends vertically from the bottom into the sample interior and brings up warm fluid while another vortex brings down cold fluid from the top; this flow field would yield a sidewall temperature signature similar to that of the LSC. Here we show by direct numerical simulations for Γ=1/2 and parameters that allow direct comparison with experiment that the spatial organization of the vertically aligned vortical structures in the convection cell do indeed yield (for the time average) a sinusoidal variation of the temperature near the sidewall, as found in the experiment. This is also the essential and nontrivial difference with the Γ=1 sample, where the vertically aligned vortices are distributed randomly.

  8. High-Efficiency Nitride-Based Solid-State Lighting

    SciTech Connect

    Paul T. Fini; Shuji Nakamura

    2005-07-30

    In this final technical progress report we summarize research accomplished during Department of Energy contract DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. Two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and the Lighting Research Center at Rensselaer Polytechnic Institute (led by Dr. N. Narendran), pursued the goals of this contract from thin film growth, characterization, and packaging/luminaire design standpoints. The UCSB team initially pursued the development of blue gallium nitride (GaN)-based vertical-cavity surface-emitting lasers, as well as ultraviolet GaN-based light emitting diodes (LEDs). In Year 2, the emphasis shifted to resonant-cavity light emitting diodes, also known as micro-cavity LEDs when extremely thin device cavities are fabricated. These devices have very directional emission and higher light extraction efficiency than conventional LEDs. Via the optimization of thin-film growth and refinement of device processing, we decreased the total cavity thickness to less than 1 {micro}m, such that micro-cavity effects were clearly observed and a light extraction efficiency of over 10% was reached. We also began the development of photonic crystals for increased light extraction, in particular for so-called ''guided modes'' which would otherwise propagate laterally in the device and be re-absorbed. Finally, we pursued the growth of smooth, high-quality nonpolar a-plane and m-plane GaN films, as well as blue light emitting diodes on these novel films. Initial nonpolar LEDs showed the expected behavior of negligible peak wavelength shift with increasing drive current. M-plane LEDs in particular show promise, as unpackaged devices had unsaturated optical output power of {approx} 3 mW at 200 mA drive current. The LRC's tasks were aimed at developing the subcomponents necessary for packaging UCSB's light emitting diodes, and packaging them to produce a white

  9. Teaching General Education Students How to Write Scientific Arguments Using Real Earth Data

    NASA Astrophysics Data System (ADS)

    Kelly, G. J.; Prothero, W. A.

    2003-12-01

    Writing activities can improve student understanding of scientific content and processes. We have studied student writing to identify the challenges that students face in composing scientific arguments and to clarify features that constitute quality in scientific writing. We have applied argumentation analysis for the assessment of students' use of evidence in a general education oceanography course. Argumentation analysis refers to the systematic examination of ways that conclusions are supported with evidence. The student writers were supported by an interactive CD-ROM, "Our Dynamic Planet," which provided students with "point and click" access to real earth data and allowed them to solve many problems associated with plate tectonics. Plate boundary types (using quakes, volcanoes, elevation profiles, and heat flow) and plate motion can be determined (seafloor age, island ages/hot spots) with this technology. First, we discuss the structure of scientific argument and how this structure can be made accessible to undergraduate students. Second, we present examples of argumentation analysis applied to student writing. These examples demonstrate how use of large scale geological data sets can be used to support student writing. Third, we present results from a series of studies to show ways that students adhere to the genre conventions of geological writing through use of theoretical claims, multiple lines of evidence, and cohesive terms. These results, combined with our evidence-based orientation to instruction, formed the basis for modifications in the course instruction. These instructional modifications include providing detailed examples of data based observations and interpretations, heuristics for assessing other students' arguments, and quick write exercises with similar but simplified writing tasks. More information about the CD-ROM may be found at http://oceanography.geol.ucsb.edu/.

  10. Reconstructing a Past Climate Using Current Multi-species' Climate Spaces

    NASA Astrophysics Data System (ADS)

    Westfall, R. D.; Millar, C. I.

    2004-12-01

    We present an analysis of a ghost forest on WhiteWing Mt at 3000 m in the eastern Sierra Nevada, southeast of Yosemite NP. Killed by a volcanic eruption about 650 years ago, the deadwood on WhiteWing dates by standard tree-ring analysis to 800-1330 CE, during the Medieval Warm Anomaly. Individual stems have been identified by wood anatomical characteristics as Pinus albicualis, P. monticola, P. jeffreyi, P. contorta, P. lambertiana, and Tsuga mertensiana. With the exception of P. albicualis, which is currently in krummholz form at this elevation, the other species are 200 m or more lower in elevation. One, P. lambertiana, is west of the Sierran crest and 600 m lower in elevation. Assuming that climatic conditions on Whitewing during this period were mutually compatible with all species, we reconstruct this climate by the intersection of the current climatic spaces of these species. We did this by first generating individual species' ranges in the Sierran ecoregions through selecting vegetation GIS polygons from the California Gap Analysis database (UCSB) that contain the individual species. Climatic spaces for each species were generated by the GIS intersection of its polygons with 4 km gridded polygons from PRISM climatic estimates (OSU); this was done for annual, January, and July maximum and minimum temperature, and precipitation, merged together for each species. Climatic intersections of the species were generated from the misclassified polygons of a discriminant analysis of species by the climatic data. The average data from these misclassified polygons suggest that the climate on WhiteWing during the existence of this forest community was 230 mm, 1oC, and 3oC greater than present in precipitation, and maximum and minimum temperature, respectively.

  11. Inverse Bloch-oscillator: Strong Thz-photocurrent resonances at the Bloch frequency

    SciTech Connect

    Unterrainer, K.; Keay, B.J.; Wanke, M.C.

    1995-12-31

    We have observed resonant changes in the current-voltage characteristics of miniband semiconductor superlattices when the Bloch frequency is resonant with a terahertz field and its harmonics: the inverse Bloch oscillator effect. The resonant feature consists of a peak in the current which grows with increasing laser intensity accompanied by a decrease of the current at the low bias side. The peak position moves linearly with the laser frequency. When the intensity is increased further the first peak starts to decrease and a second peak at about twice the voltage of the first peak is observed due to a two photon resonance. At the highest intensities we observe up to a four photon resonance. A superlattice is expected to show negative differential conductance due to the strong nonparabolicity of the miniband. In this situation the carriers should undergo Bloch oscillations with a frequency {omega}{sub B} = eEd/h. Transient Bloch oscillations of photo excited carriers have been observed in time resolved Thz emission measurements. However, the possibility of Thz generation form a DC voltage biased superlattice is still under discussion. We have approached this problem by exploring the inverse Bloch oscillator effect in a superlattice excited by the Thz radiation form the UCSB FEL. The superlattice consists of 40 periods of 80{angstrom} GaAs wells and 20{angstrom} Al{sub 0.3}Ga{sub 0.7}As barriers. To couple the electric field of the Terahertz radiation parallel to the growth direction a coplanar bowtie antenna has been employed. Our results show clearly that the external radiation couples to Bloch oscillations in contrary to theoretical suggestions that Thz radiation would not couple to a uniform Wannier Stark ladder. We conclude that this result is intimately related to dissipation and line broadening of the otherwise identical states in the ladder: absorption appears above the Wannier Stark splitting ({omega}{sub B}<{omega}) and gain below ({omega}{sub B}>{omega}).

  12. Symmetry and aesthetics in introductory physics: An experiment in interdisciplinary physics and fine arts education

    NASA Astrophysics Data System (ADS)

    van der Veen, Janet Krause

    In a recent editorial in Physics Today (July, 2006, p. 10) the ability of physicists to "imagine new realities" was correlated with what have been traditionally considered non-scientific qualities of imagination and creativity, which are usually associated with fine arts. In view of the current developments in physics of the 21st Century, including the searches for cosmic dark energy and evidence from the Large Hadron Collider which, it is hoped, will verify or refute the proposals of String Theory, the importance of developing creativity and imagination through education is gaining recognition. Two questions are addressed by this study: First, How can we bring the sense of aesthetics and creativity, which are important in the practice of physics, into the teaching and learning of physics at the introductory college level, without sacrificing the mathematical rigor which is necessary for proper understanding of physics? Second, How can we provide access to physics for a diverse population of students which includes physics majors, arts majors, and future teachers? An interdisciplinary curriculum which begins with teaching math as a language of nature, and utilizes arts to help visualize the connections between mathematics and the physical universe, may provide answers to these questions. In this dissertation I describe in detail the case study of the eleven students - seven physics majors and four arts majors - who participated in an experimental course, Symmetry and Aesthetics in Introductory Physics, in Winter Quarter, 2007, at UCSB's College of Creative Studies. The very positive results of this experiment suggest that this model deserves further testing, and could provide an entry into the study of physics for physics majors, liberal arts majors, future teachers, and as a foundation for media arts and technology programs.

  13. Field Trial of Distributed Acoustic Sensing Using Active Sources at Garner Valley, California

    NASA Astrophysics Data System (ADS)

    Wang, H. F.; Lord, N. E.; Chalari, A.; Lancelle, C.; Baldwin, J. A.; Castongia, E.; Fratta, D.; Nigbor, R. L.; Karaulanov, R.

    2014-12-01

    An optical fiber Distributed Acoustic Sensor array was deployed in a shallow trench at the site of the Garner Valley Downhole Array (GVDA) in southern California. The site was operated as a collaborator of the Network for Earthquake Engineering Simulation (NEES) by UCSB. The fiber-optic cable layout approximated a rectangle whose dimensions were roughly 160 meters by 80 meters. The layout included two subdiagonals to provide a variety of orientations of the cable relative to source locations. The study included different seismic sources deployed at a number of surveyed positions: a 45 kN shear shaker operated at the site by NEES@UCLA, a portable 450 N shaker, a small Vibroseis truck, and hammer blows on a steel plate to map cable locations. Several dozen separate tests were recorded in which each test typically included ten repeats. The data were utilized for several studies. First, the characteristics of the recorded signals were analyzed for directivity and sensitivity of the cable response (Lancelle et al., 2014, this meeting). The DAS system recorded dynamic ground events in the direction of the cable and hence comparisons with geophones required signal processing. The one-meter spacing of DAS traces could be well correlated over distances of a few meters. Second, swept-sine sources were used to obtain surface-wave velocity dispersion to determine near-surface shear-wave velocity distribution using Multispectral Analysis of Surface Waves (MASW) (Baldwin et al., 2014, this meeting). The results were in good agreement with previous Vibroseis results at the site (Stokoe et al. 2004). Third, a new method for time-frequency filtering was developed for extracting the surface-wave phase velocities from uncorrelated receiver traces (Lord et al., 2014, this meeting).

  14. A meta-analysis reveals a positive correlation between genetic diversity metrics and environmental status in the long-lived seagrass Posidonia oceanica.

    PubMed

    Jahnke, Marlene; Olsen, Jeanine L; Procaccini, Gabriele

    2015-05-01

    The seagrass Posidonia oceanica is a key engineering species structuring coastal marine systems throughout much of the Mediterranean basin. Its decline is of concern, leading to the search for short- and long-term indicators of seagrass health. Using ArcGIS maps from a recent, high-resolution (1-4 km) modelling study of 18 disturbance factors affecting coastal marine systems across the Mediterranean (Micheli et al. 2013, http://globalmarine.nceas.ucsb.edu/mediterranean/), we tested for correlations with genetic diversity metrics (allelic diversity, genotypic/clonal diversity and heterozygosity) in a meta-analysis of 56 meadows. Contrary to initial predictions, weak but significantly positive correlations were found for commercial shipping, organic pollution (pesticides) and cumulative impact. This counterintuitive finding suggests greater resistance and resilience of individuals with higher genetic and genotypic diversity under disturbance (at least for a time) and/or increased sexual reproduction under an intermediate disturbance model. We interpret the absence of low and medium levels of genetic variation at impacted locations as probable local extinctions of individuals that already exceeded their resistance capacity. Alternatively, high diversity at high-impact sites is likely a temporal artefact, reflecting the mismatch with pre-environmental impact conditions, especially because flowering and sexual recruitment are seldom observed. While genetic diversity metrics are a valuable tool for restoration and mitigation, caution must be exercised in the interpretation of correlative patterns as found in this study, because the exceptional longevity of individuals creates a temporal mismatch that may falsely suggest good meadow health status, while gradual deterioration of allelic diversity might go unnoticed. PMID:25819368

  15. A meta-analysis reveals a positive correlation between genetic diversity metrics and environmental status in the long-lived seagrass Posidonia oceanica.

    PubMed

    Jahnke, Marlene; Olsen, Jeanine L; Procaccini, Gabriele

    2015-05-01

    The seagrass Posidonia oceanica is a key engineering species structuring coastal marine systems throughout much of the Mediterranean basin. Its decline is of concern, leading to the search for short- and long-term indicators of seagrass health. Using ArcGIS maps from a recent, high-resolution (1-4 km) modelling study of 18 disturbance factors affecting coastal marine systems across the Mediterranean (Micheli et al. 2013, http://globalmarine.nceas.ucsb.edu/mediterranean/), we tested for correlations with genetic diversity metrics (allelic diversity, genotypic/clonal diversity and heterozygosity) in a meta-analysis of 56 meadows. Contrary to initial predictions, weak but significantly positive correlations were found for commercial shipping, organic pollution (pesticides) and cumulative impact. This counterintuitive finding suggests greater resistance and resilience of individuals with higher genetic and genotypic diversity under disturbance (at least for a time) and/or increased sexual reproduction under an intermediate disturbance model. We interpret the absence of low and medium levels of genetic variation at impacted locations as probable local extinctions of individuals that already exceeded their resistance capacity. Alternatively, high diversity at high-impact sites is likely a temporal artefact, reflecting the mismatch with pre-environmental impact conditions, especially because flowering and sexual recruitment are seldom observed. While genetic diversity metrics are a valuable tool for restoration and mitigation, caution must be exercised in the interpretation of correlative patterns as found in this study, because the exceptional longevity of individuals creates a temporal mismatch that may falsely suggest good meadow health status, while gradual deterioration of allelic diversity might go unnoticed.

  16. Validation and Application of PHYDOTax In The Santa Barbara Channel

    NASA Astrophysics Data System (ADS)

    Schafer, C. B.; Palacios, S. L.; Broughton, J.; Kudela, R. M.

    2013-12-01

    Phytoplankton Functional Types(PFTs) are conceptual groupings of phytoplankton based on physical or functional characteristics. Understanding phytoplankton is essential in our study of how ecosystems function and in monitoring carbon flow. PHYDOTax is a PFT algorithm that discriminates taxon-specific biomass in images from airborne and spaceborne hyperspectral sensors. The PHYDOTax algorithm uses a spectral library and an inverse matrix approach to deconvolve pure phytoplankton spectral end-members from spectra of natural waters. The spectral library used in development was created from phytoplankton taxa found in Monterey Bay, CA and the California Current System (CCS). PHYDOTax has only been validated in Monterey Bay and for only one airborne sensor, Spectroscopic Aerial Mapping System with On-board Navigation (SAMSON). The objectives of this research were to apply PHYDOTax to a different region of the CCS, Santa Barbara Channel (SBC), and to test the usability of PHYDOTax with a different airborne imager, Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). PHYDOTax was modified to accommodate the reduced spectral resolution of AVIRIS, which has fewer wavelengths than the SAMSON imagery that was used to validate the model for Monterey Bay. PHYDOTax's predictions were consistent with cell-count data from whole water samples on June 5, 2013, courtesy of the Plumes and Blooms Cruise (UCSB). PHYDOTax's ability to perform in another area of the CCS shows promise that it may be accurately applied to the west coast of the US. PHYDOTax's ability to perform with lower spectral resolution imagery, suggests that it may it may be robust enough to be down-sampled to multi-spectral resolution inputs. This opens the possibility of applying PHYDOTax to historical (SeaWiFS, MODIS, MERIS), existing (VIIRS, HICO), and future (PACE, GEO-CAPE) sensors to describe temporal trends in phytoplankton distribution and carbon flow in the ocean and to build continuity among the sensor

  17. Present developments and status of electron sources for high power gyrotron tubes and free electron masers

    NASA Astrophysics Data System (ADS)

    Thumm, M.

    1997-02-01

    Gyrotron oscillators are mainly used as high power mm-wave sources for start-up, electron cyclotron heating (ECH) and diagnostics of magnetically confined plasmas for controlled thermonuclear fusion research. 140 GHz (110 GHz) gyrotrons with output power Pout = 0.55 MW (0.93 MW), pulse length τ = 3.0 s (2.0 s) and efficiency η = 40% (38%) are commercially available. Total efficiencies around 50% have been achieved using single-stage depressed collectors. Diagnostic gyrotrons deliver Pout = 40 kW with τ = 40 μs at frequencies up to 650 GHz ( η≥4%). Recently, gyrotron oscillators have also been successfully used in materials processing, for example sintering of high performance, structural and functional ceramics. Such technological applications require gyrotrons with f≥24 GHz, Pout = 10-100 kW, CW, η≥30%. This paper reports on recent achievements in the development of very high power mm-wave gyrotron oscillators for long pulse or CW operation. In addition a short overview of the present development status of gyrotrons for technological applications, gyroklystron amplifiers, gyro-TWT amplifiers, cyclotron autoresonance masers (CARMs) and free electron masers (FEMs) is given. The most impressive FEM output parameters are: Pout = 2GW, τ = 20 ns, η = 13% at 140 GHz (LLNL) and Pout = 15 kW, τ = 20 μs, η = 5% in the range from 120 to 900 GHz (UCSB). In gyro-devices, magnetron injection guns (MIGs) operating in the temperature limited current regime have thus far been used most successfully. Diode guns as well as triode guns with a modulating anode are employed. Tests of a MIG operated under space-charge limited conditions have been not very successful. Electrostatic CW FEMs are driven by thermionic Pierce guns whereas pulsed high power devices employ many types of accelerators as drivers for example pulse-line accelerators, microtrons and induction or rf linacs, using field and photo emission cathodes.

  18. Aerosol Optical Depth (AOD) retrieval using simultaneous GOES-East and GOES-West reflected radiances over the Western US

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Hoff, R. M.; Kondragunta, S.; Laszlo, I.; Lyapustin, A.

    2012-10-01

    Aerosol Optical Depth (AOD) in the Western United States is observed independently by both the GOES-East and GOES-West imagers. The GASP (GOES Aerosol/Smoke Product) aerosol optical depth retrieval algorithm treats each satellite as a unique sensor and thus NOAA obtains two separate aerosol optical depth values at the same time for the same location. The TOA radiances and the associated derived optical depths can be quite different due to the different viewing geometries with large difference in solar-scattering angles. In order to fully exploit the simultaneous observations and generate consistent AOD retrievals from the two satellites, the authors develop a new aerosol optical depth retrieval algorithm that uses data from both satellites. The algorithm uses combined GOES-East and GOES-West visible channel TOA reflectance and daily average AOD from GOES Multi-Angle Implementation of Atmospheric Correction (GOES-MAIAC) on clear days (AOD less than 0.3), when diurnal variation of AOD is low, to retrieve surface BRDF. The known BRDF shape is applied on subsequent days to retrieve BRDF and AOD. The algorithm is validated at three AERONET sites over the Western US. The AOD retrieval accuracy from the hybrid technique using the two satellites is similar to that from one satellite over UCSB and Railroad Valley. Improvement of the accuracy is observed at Boulder. The correlation coefficients between the GOES AOD and AERONET AOD are in the range of 0.67 to 0.81 over the three sites. The hybrid algorithm has more data coverage compared to the single satellite retrievals over surfaces with high reflectance. The number of coincidences with AERONET observations increases from the use of two-single satellite algorithms by 5-80% for the three sites. With the application of the new algorithm, consistent AOD retrievals and better retrieval coverages can be obtained using the data from the two GOES satellite imagers.

  19. A multi-angle aerosol optical depth retrieval algorithm for geostationary satellite data over the United States

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Lyapustin, A.; Wang, Y.; Kondragunta, S.; Laszlo, I.; Ciren, P.; Hoff, R. M.

    2011-12-01

    Aerosol optical depth (AOD) retrievals from geostationary satellites have high temporal resolution compared to the polar orbiting satellites and thus enable us to monitor aerosol motion. However, current Geostationary Operational Environmental Satellites (GOES) have only one visible channel for retrieving aerosols and hence the retrieval accuracy is lower than those from the multichannel polar-orbiting satellite instruments such as the Moderate Resolution Imaging Spectroradiometer (MODIS). The operational GOES AOD retrieval algorithm (GOES Aerosol/Smoke Product, GASP) uses 28-day composite images from the visible channel to derive surface reflectance, which can produce large uncertainties. In this work, we develop a new AOD retrieval algorithm for the GOES imager by applying a modified Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm. The algorithm assumes the surface Bidirectional Reflectance Distribution Function (BRDF) in the channel 1 of GOES is proportional to seasonal average MODIS BRDF in the 2.1 μm channel. The ratios between them are derived through time series analysis of the GOES visible channel images. The results of AOD and surface reflectance retrievals are evaluated through comparisons against those from Aerosol Robotic Network (AERONET), GASP, and MODIS. The AOD retrievals from the new algorithm demonstrate good agreement with AERONET retrievals at several sites across the US with correlation coefficients ranges from 0.71 to 0.85 at five out of six sites. At the two western sites Railroad Valley and UCSB, the MAIAC AOD retrievals have correlations of 0.8 and 0.85 with AERONET AOD, and are more accurate than GASP retrievals, which have correlations of 0.7 and 0.74 with AERONET AOD. At the three eastern sites, the correlations with AERONET AOD are from 0.71 to 0.81, comparable to the GASP retrievals. In the western US where surface reflectance is higher than 0.15, the new algorithm also produces larger AOD retrieval coverage

  20. Garner Valley Vibroseis Data Processing Using Time-Frequency Filtering Techniques to Remove Unwanted Harmonics and External Noise

    NASA Astrophysics Data System (ADS)

    Lord, N. E.; Wang, H. F.; Fratta, D.; Lancelle, C.; Chalari, A.

    2015-12-01

    Time-frequency filtering techniques can greatly improve data quality when combined with frequency swept seismic sources (vibroseis) recorded by seismic arrays by removing unwanted source harmonics or external noise sources (e.g., cultural or ambient noise). A source synchronous filter (SSF) is a time-frequency filter which only passes a specified width frequency band centered on the time varying frequency of the seismic source. A source delay filter (SDF) is a time-frequency filter which only passes those frequencies from the source within a specified delay time range. Both of these time-frequency filters operate on the uncorrelated vibroseis data and allow separate analysis of the source fundamental frequency and each harmonic. In either technique, the time-frequency function of the source can be captured from the source encoder or specified using two or more time-frequency points. SSF and SDF were both used in the processing of the vibroseis data collected in the September 2013 seismic experiment conducted at the NEES@UCSB Garner Valley field site. Three vibroseis sources were used: a 45 kN shear shaker, a 450 N portable mass shaker, and a 26 kN vibroseis truck. Seismic signals from these sources were recorded by two lines of 1 and 3 component accelerometers and geophones, and the Silixa Ltd's intelligent Distributed Acoustic Sensing (iDASTM ) system connected to 762 m of trenched fiber optical cable in a larger rectangular area. SSF and SDF improved vibroseis data quality, simplified data interpretation, and allowed new analysis techniques. This research is part of the larger DOE's PoroTomo project (URL: http://geoscience.wisc.edu/feigl/porotomo).

  1. Hybrid III-V Silicon Lasers

    NASA Astrophysics Data System (ADS)

    Bowers, John

    2014-03-01

    Abstract: A number of important breakthroughs in the past decade have focused attention on Si as a photonic platform. We review here recent progress in this field, focusing on efforts to make lasers, amplifiers, modulators and photodetectors on or in silicon. We also describe optimum quantum well design and distributed feedback cavity design to reduce the threshold and increase the efficiency and power output. The impact active silicon photonic integrated circuits could have on interconnects, telecommunications and on silicon electronics is reviewed. Biography: John Bowers holds the Fred Kavli Chair in Nanotechnology, and is the Director of the Institute for Energy Efficiency and a Professor in the Departments of Electrical and Computer Engineering and Materials at UCSB. He is a cofounder of Aurrion, Aerius Photonics and Calient Networks. Dr. Bowers received his M.S. and Ph.D. degrees from Stanford University and worked for AT&T Bell Laboratories and Honeywell before joining UC Santa Barbara. Dr. Bowers is a member of the National Academy of Engineering and a fellow of the IEEE, OSA and the American Physical Society. He is a recipient of the OSA/IEEE Tyndall Award, the OSA Holonyak Prize, the IEEE LEOS William Streifer Award and the South Coast Business and Technology Entrepreneur of the Year Award. He and coworkers received the EE Times Annual Creativity in Electronics (ACE) Award for Most Promising Technology for the hybrid silicon laser in 2007. Bowers' research is primarily in optoelectronics and photonic integrated circuits. He has published ten book chapters, 600 journal papers, 900 conference papers and has received 54 patents. He has published 180 invited papers and conference papers, and given 16 plenary talks at conferences. As well as Chong Zhang.

  2. The National Center for Ecological Analysis and Synthesis

    NASA Astrophysics Data System (ADS)

    Reichman, O. J.

    2001-12-01

    The National Center for Ecological Analysis and Synthesis was created in May 1995 with funding from NSF, the State of California, and UCSB. The Center is based on the premise that a significant amount is known about the environment, but that it is scattered in many places and formats. The purpose of the Center is to obtain and utilize existing information to address important ecological questions. The Center was recently funded by NSF for an additional 6 years. The Center supports several types of research activities. A primary mode of research is through Working Groups, projects made up of approximately a dozen scientists who come to NCEAS to concentrate on specific issues that require in-depth analysis of data and synthesis of ideas. In addition, up to six sabbatical visitors (Center Fellows) and 18 Postdoctoral Associates are in residence at the Center. Since the Center began, over 2,400 scientists (including hundreds of students) from the US and 40 other countries have participated in research activities. These scientists have produced more than 380 scientific articles published in 65 journals and 8 books. The topics addressed by research projects at the Center range from the value of the planet's ecosystem services to the ecological impacts of global climate change. The Center is actively involved in developing a Knowledge Network for Biocomplexity (knb.ecoinformatics.org) involving information management tools for access to ecological data, which are highly dispersed and heterogeneous. The research and implementation involves developing a desktop data management system for individuals researchers and research groups. Embedded in the system would be capabilities for developing metadata (data about data), making both the metadata and raw data available to the broad community interested in such information, and data query tools (knb.ecoinformatics.org).

  3. A linear coherent integrated receiver based on a broadband optical phase-locked loop

    NASA Astrophysics Data System (ADS)

    Ramaswamy, Anand

    Optical Phase-Locked Loops (OPLL) have diverse applications in future communication systems. They can be used in high sensitivity homodyne phase-shift keying receivers for phase noise reduction, provided sufficient loop bandwidth is maintained. Alternative phase-locked loop applications include coherent synchronization of laser arrays and frequency synthesis by offset locking. In this work, a broadband OPLL based coherent receiver is used for linear phase demodulation. Phase modulated (PM) analog optical links have the potential to outperform conventional direct detection links. However, their progress has been stymied by the lack of a linear phase demodulator. We describe how feedback can be used to suppress non-linearities arising from the phase demodulation process. The receiver concept is demonstrated at low frequencies and is found to improve the Spurious Free Dynamic Range (SFDR) of an experimental analog link by over 20dB. In order to extend the operation of the receiver to microwave frequencies, latencies arising from physical delays in the feedback path need to be dramatically reduced. To facilitate this, monolithic and hybrid versions of the receiver based on compact integration of InP photonic integrated circuits (PIC) with InP and SiGe electronic integrated circuits (EIC) have been developed at UCSB. In this work, we develop novel measurement techniques to characterize the linearity of the individual components of the PIC, namely, the semiconductor photodiodes and optical phase modulators. We then demonstrate the operation of the receiver in a high power analog link. The OPLL based receiver has a bandwidth of 1.5GHz. The link gain and shot-noise limited SFDR at 300MHz are -2dB and 125dB-Hz2/3, respectively. Further, optical sampling downconversion is demonstrated as a viable technique to increase the operating frequency of the receiver beyond the baseband range.

  4. Limited Flow of Continental Crust at UHP Depths: Coupled Age and Trace-Element Analyses of Titanite in the Western Gneiss Region, Norway

    NASA Astrophysics Data System (ADS)

    Garber, J. M.; Hacker, B. R.; Kylander-Clark, A. R.

    2015-12-01

    Coupled age and trace-element data from titanites in the Western Gneiss Region (WGR) of Norway suggest that continental crust underwent limited recrystallization and ductile flow through ~40 My of deep subduction and subsequent exhumation. Precambrian igneous titanites in granitic to tonalitic orthogneisses from the WGR were metastably preserved though Caledonian ultrahigh-pressure (UHP) metamorphism and variably recrystallized through subsequent amphibolite-facies metamorphism from ~420-385 Ma. The inherited Precambrian titanites are not present everywhere but rather cluster primarily in a cooler "southern domain" (peak T ~650oC) and a hotter "northern domain" (peak T ~750-800oC).Titanite data were collected using LASS (laser-ablation split stream inductively-coupled plasma mass spectrometry) at UCSB, and a principal component analysis (PCA) was used to define age and trace-element populations. These data indicate that inherited titanites are LREE-enriched, HFSE-enriched, and have higher Th/U, consistent with Precambrian neocrystallization from a granitic melt. In contrast, the recrystallized titanites have generally lower Th/U and flat, LREE-depleted, or hump-shaped trace-element patterns. These data suggest that (1) Caledonian titanite recrystallization occurred in the presence of LREE-depleted melts or fluids, or that (2) recrystallization was accompanied by a "typical" granitic melt, but that titanite/bulk-rock distribution coefficients are different for neo- and recrystallization; on-going whole-rock analyses will clarify these hypotheses. Critically, the geochemical signature of recrystallized titanite in felsic orthogneisses is comparable across the entire WGR - emphasizing that the petrologic process of titanite recrystallization was similar orogen-wide, but was less extensive in the domains where inherited titanite was preserved. In this case, large volumes of crust outside of the "old domains" may also have retained metastable titanite during subduction

  5. Keeping our focus: a perspective on distance learning and the large introductory science class

    NASA Astrophysics Data System (ADS)

    Prothero, William A.

    2000-07-01

    The internet and worldwide web provide powerful new education and information delivery capabilities which can be used to achieve educational goals. However, it is important to review overall trends in science teaching practice and attempt to identify areas where network learning is likely to make strong contributions and where it may be weak. It is generally agreed that science knowledge is most effectively acquired when students apply a range of cognitive processes during the learning process. Trends in science education are directed toward an emphasis in active learning and group learning, increased reliance on writing, increased use of computers to provide students with access to large datasets for open-ended problems, and depth of treatment is emphasized over coverage of many subjects. Experience gained in large introductory classes is useful in designing effective network environments. The UCSB Oceanography Class is typical with 200-300 students per quarter, 3 h of lecture, and 2 h of lab per week. The focus of a portion of the class is on learning about science by doing science. Students must pose a problem related to plate tectonics to investigate, use the "Our Dynamic Planet" CD-ROM to acquire data from its datasets, and write a scientific paper based on their investigation. Network technology is used extensively for homework entry and automatic grading, and student access to their grades for individual activities. A class is framed in terms of content, presence, and social context. Except for presence, network approaches could provide substantial improvements. Technology developments in peer review software and simple (technically) posting of student work to the network, combined with bulletin board, chat and listserves, could support the development of a social context. Experience suggests that the success of network approaches will depend strongly on individual student capabilities, needs and goals.

  6. Remote Sensing Information Science Research

    NASA Technical Reports Server (NTRS)

    Clarke, Keith C.; Scepan, Joseph; Hemphill, Jeffrey; Herold, Martin; Husak, Gregory; Kline, Karen; Knight, Kevin

    2002-01-01

    This document is the final report summarizing research conducted by the Remote Sensing Research Unit, Department of Geography, University of California, Santa Barbara under National Aeronautics and Space Administration Research Grant NAG5-10457. This document describes work performed during the period of 1 March 2001 thorough 30 September 2002. This report includes a survey of research proposed and performed within RSRU and the UCSB Geography Department during the past 25 years. A broad suite of RSRU research conducted under NAG5-10457 is also described under themes of Applied Research Activities and Information Science Research. This research includes: 1. NASA ESA Research Grant Performance Metrics Reporting. 2. Global Data Set Thematic Accuracy Analysis. 3. ISCGM/Global Map Project Support. 4. Cooperative International Activities. 5. User Model Study of Global Environmental Data Sets. 6. Global Spatial Data Infrastructure. 7. CIESIN Collaboration. 8. On the Value of Coordinating Landsat Operations. 10. The California Marine Protected Areas Database: Compilation and Accuracy Issues. 11. Assessing Landslide Hazard Over a 130-Year Period for La Conchita, California Remote Sensing and Spatial Metrics for Applied Urban Area Analysis, including: (1) IKONOS Data Processing for Urban Analysis. (2) Image Segmentation and Object Oriented Classification. (3) Spectral Properties of Urban Materials. (4) Spatial Scale in Urban Mapping. (5) Variable Scale Spatial and Temporal Urban Growth Signatures. (6) Interpretation and Verification of SLEUTH Modeling Results. (7) Spatial Land Cover Pattern Analysis for Representing Urban Land Use and Socioeconomic Structures. 12. Colorado River Flood Plain Remote Sensing Study Support. 13. African Rainfall Modeling and Assessment. 14. Remote Sensing and GIS Integration.

  7. Catalytic conversion of nonfood woody biomass solids to organic liquids.

    PubMed

    Barta, Katalin; Ford, Peter C

    2014-05-20

    This Account outlines recent efforts in our laboratories addressing a fundamental challenge of sustainability chemistry, the effective utilization of biomass for production of chemicals and fuels. Efficient methods for converting renewable biomass solids to chemicals and liquid fuels would reduce society's dependence on nonrenewable petroleum resources while easing the atmospheric carbon dioxide burden. The major nonfood component of biomass is lignocellulose, a matrix of the biopolymers cellulose, hemicellulose, and lignin. New approaches are needed to effect facile conversion of lignocellulose solids to liquid fuels and to other chemical precursors without the formation of intractable side products and with sufficient specificity to give economically sustainable product streams. We have devised a novel catalytic system whereby the renewable feedstocks cellulose, organosolv lignin, and even lignocellulose composites such as sawdust are transformed into organic liquids. The reaction medium is supercritical methanol (sc-MeOH), while the catalyst is a copper-doped porous metal oxide (PMO) prepared from inexpensive, Earth-abundant starting materials. This transformation occurs in a single stage reactor operating at 300-320 °C and 160-220 bar. The reducing equivalents for these transformations are derived by the reforming of MeOH (to H2 and CO), which thereby serves as a "liquid syngas" in the present case. Water generated by deoxygenation processes is quickly removed by the water-gas shift reaction. The Cu-doped PMO serves multiple purposes, catalyzing substrate hydrogenolysis and hydrogenation as well as the methanol reforming and shift reactions. This one-pot "UCSB process" is quantitative, giving little or no biochar residual. Provided is an overview of these catalysis studies beginning with reactions of the model compound dihydrobenzofuran that help define the key processes occurring. The initial step is phenyl-ether bond hydrogenolysis, and this is followed by

  8. CAMPARE and Cal-Bridge: Two Institutional Networks Increasing Diversity in Astronomy

    NASA Astrophysics Data System (ADS)

    Rudolph, Alexander L.; Impey, Chris David; Phillips, Cynthia B.; Povich, Matthew S.; Prather, Edward E.; Smecker-Hane, Tammy A.

    2015-01-01

    We describe two programs, CAMPARE and Cal-Bridge, with the common mission of increasing participation of groups traditionally underrepresented in astronomy, particularly underrepresented minorities and women, through summer research opportunities, in the case of CAMPARE, scholarships in the case of Cal-Bridge, and significant mentoring in both programs, leading to an increase in their numbers successfully pursuing a PhD in the field.CAMPARE is an innovative REU-like summer research program, currently in its sixth year, comprising a network of comprehensive universities and community colleges in Southern California and Arizona (most of which are minority serving institutions), and ten major research institutions (University of Arizona Steward Observatory, the SETI Institute, JPL, Caltech, and the five Southern California UC campuses, UCLA, UCI, UCSD, UCR, and UCSB).In its first five summers, CAMPARE sent a total of 49 students from 10 different CSU and community college campuses to 5 research sites of the program. Of these 49 participants, 25 are women and 24 are men; 22 are Hispanic, 4 are African American, and 1 is Native American, including 6 female Hispanic and 2 female African-American participants. Twenty-one (21) CAMPARE participants have graduated from college, and more than half (11) have attended or are attending a graduate program, including 8 enrolled in PhD or Master's-to-PhD programs. Over twenty CAMPARE students have presented at the AAS and other national meetings.The Cal-Bridge program is a diverse network of higher education institutions in Southern California, including 5 UC campuses, 8 CSU campuses, and 7 community colleges dedicated to the goal of increasing the number of underrepresented minority and female students attending graduate school in astronomy or related fields. We have recently selected our inaugural group of five 2014 Cal-Bridge Scholars, including four women (two Hispanic and one part Native American), and one Hispanic man

  9. CAMPARE and Cal-Bridge: Two Institutional Networks Increasing Diversity in Astronomy

    NASA Astrophysics Data System (ADS)

    Rudolph, Alexander L.; Impey, Chris David; Phillips, Cynthia B.; Povich, Matthew S.; Prather, Edward E.; Smecker-Hane, Tammy A.

    2015-01-01

    We describe two programs, CAMPARE and Cal-Bridge, with the common mission of increasing participation of groups traditionally underrepresented in astronomy, particularly underrepresented minorities and women, through summer research opportunities, in the case of CAMPARE, scholarships in the case of Cal-Bridge, and significant mentoring in both programs, leading to an increase in their numbers successfully pursuing a PhD in the field.CAMPARE is an innovative REU-like summer research program, currently in its sixth year, comprising a network of comprehensive universities and community colleges in Southern California and Arizona (most of which are minority serving institutions), and ten major research institutions (University of Arizona Steward Observatory, the SETI Institute, JPL, Caltech, and the five Southern California UC campuses, UCLA, UCI, UCSD, UCR, and UCSB).In its first five summers, CAMPARE sent a total of 49 students from 10 different CSU and community college campuses to 5 research sites of the program. Of these 49 participants, 25 are women and 24 are men; 22 are Hispanic, 4 are African American, and 1 is Native American, including 6 female Hispanic and 2 female African-American participants. Twenty-one (21) CAMPARE participants have graduated from college, and more than half (11) have attended or are attending a graduate program, including 8 enrolled in PhD or Master's-to-PhD programs. Over twenty CAMPARE students have presented at the AAS and other national meetings.The Cal-Bridge program is a diverse network of higher education institutions in Southern California, including 5 UC campuses, 8 CSU campuses, and 7 community colleges dedicated to the goal of increasing the number of underrepresented minority and female students attending graduate school in astronomy or related fields. We have recently selected our inaugural group of five 2014 Cal-Bridge Scholars, including four women (two Hispanic and one part Native American), and one Hispanic man

  10. Activites to Support and Assess Student Understanding of Earth Data

    NASA Astrophysics Data System (ADS)

    Prothero, W. A.; Regev, J.

    2004-12-01

    In order to use data effectively, learners must construct a mental model that allows them to understand and express spatial relationships in data, relationships between different data types, and relationships between the data and a theoretical model. Another important skill is the ability to identify gross patterns and distinguish them from details that may require increasingly sophisticated models. Students must also be able to express their understanding, both to help them frame their understanding for themselves, and for assessment purposes. Research in learning unequivocally shows that writing about a subject increases understanding of that subject. In UCSB's general education oceanography class, a series of increasingly demanding activities culminates in two science papers that use earth data. These activities are: 1) homework problems, 2) in-class short writing activities, 3) lab section exploration activities and presentations, and 4) the science paper. The subjects of the two papers are: Plate Tectonics and Ocean and Climate. Each student is a member of a group that adopts a country and must relate their paper to the environment of their country. Data are accessed using the "Our Dynamic Planet" and "Global Ocean Data Viewer" (GLODV) CD's. These are integrated into EarthEd Online, a software package which supports online writing, review, commenting, and return to the student. It also supports auto-graded homework assignments, grade calculation, and other class management functions. The writing assignments emphasize the construction of a scientific argument. This process is explained explicitly, requiring statements that: 1) include an observation or description of an observation (e.g. elevation profiles, quakes), 2) name features based on the observation (e.g. trench, ridge), 3) describe of features (e.g. trends NW, xxxkm long), 4) describe relationships between features (e.g. quakes are parallel to trench), 5) describe a model or theory (e.g. cartoon type

  11. Preserving the Context of Science Data

    NASA Astrophysics Data System (ADS)

    Janée, G.; Frew, J.

    2008-12-01

    documentation, and may reside in the same archive or in another. Cross-archive references capture whole-archive dependencies (summarized by whole-archive descriptors located at the root of each archive), allowing us to describe the familiar situation of an entire archive referencing a format registry, or a source data center. We describe as a case study the archiving of the Earth science data records (ESDRs) being produced by the UCSB NASA-funded Ocean MEaSUREs project. The data's context includes complex formats, scientific literature, and software (both commercial and locally-developed). The data's provenance includes dependencies on multiple versions, parameter settings, and satellite data sources. By addressing how much context is required to preserve these data, we hope to begin to answer the question: What does it mean for a library to assume responsibility for a science dataset?

  12. Si/Ge photodiodes for coherent and analog communication

    NASA Astrophysics Data System (ADS)

    Piels, Molly

    allows optimization of the absorption profile independently from the RC-limited frequency response and compression current and ultimately enables larger saturation current-bandwidth products. This thesis includes the first theory, fabrication, and measurement of a uni-traveling carrier photodiode on the Si/Ge platform. Key contributions include an accurate nonlinear device model and a complete set of processes and design rules for fabricating Ge devices in the UCSB nanofab. The UTC structure is shown to be useful in extending the bandwidth and power handling capabilities of waveguide-integrated photodiodes, especially at high frequencies.

  13. Aerosol optical depth (AOD) retrieval using simultaneous GOES-East and GOES-West reflected radiances over the western United States

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Hoff, R. M.; Kondragunta, S.; Laszlo, I.; Lyapustin, A.

    2013-02-01

    Aerosol optical depth (AOD) in the western United States is observed independently by both the (Geostationary Operational Environmental Satellites) GOES-East and GOES-West imagers. The GASP (GOES Aerosol/Smoke Product) aerosol optical depth retrieval algorithm treats each satellite as a unique sensor and thus obtains two separate aerosol optical depth values at the same time for the same location. The TOA (the top of the atmosphere) radiances and the associated derived optical depths can be quite different due to the different viewing geometries with large difference in solar-scattering angles. In order to fully exploit the simultaneous observations and generate consistent AOD retrievals from the two satellites, the authors develop a new "hybrid" aerosol optical depth retrieval algorithm that uses data from both satellites. The algorithm uses both GOES-East and GOES-West visible channel TOA reflectance and daily average AOD from GOES Multi-Angle Implementation of Atmospheric Correction (GOES-MAIAC) on low AOD days (AOD less than 0.3), when diurnal variation of AOD is low, to retrieve surface BRDF (Bidirectional Reflectance Distribution Function). The known BRDF shape is applied on subsequent days to retrieve BRDF and AOD. The algorithm is validated at three AERONET sites over the western US. The AOD retrieval accuracy from the "hybrid" technique using the two satellites is similar to that from one satellite over UCSB (University of California Santa Barbara) and Railroad Valley, Nevada. Improvement of the accuracy is observed at Boulder, Colorado. The correlation coefficients between the GOES AOD and AERONET AOD are in the range of 0.67 to 0.81. More than 74% of AOD retrievals are within the error of ±(0.05 + 0.15 τ) compared to AERONET AOD. The hybrid algorithm has more data coverage compared to the single satellite retrievals over surfaces with high surface reflectance. For single observation areas the number of valid AOD data increases from the use of two

  14. PREFACE: Nanosafe 2012: International Conferences on Safe Production and Use of Nanomaterials

    NASA Astrophysics Data System (ADS)

    Tardif, François

    2013-04-01

    , FR) Co-chair: Georgios KATALAGARIANAKIS (EC, BE) Mélanie AUFFAN (CEREGE, FR) Jorge BOCZKOWSKI (INSERM, FR) Jean-Yves BOTTERO (CEREGE, FR) Jacques BOUILLARD (INERIS, FR) Derk BROUWER (TNO, NL) Marie CARRIERE (CEA, FR) Claude EMOND (U. MONTREAL, CA) Cassandra ENGEMAN (UCSB, USA) Eric GAFFET (CNRS, FR) François GENSDARMES (IRSN, FR) Alexei GRINBAUM (CEA, FR) Antje GROBE (U.STUTTGART, DE) Peter HOET (KUL, BE) Eric QUEMENEUR (CEA, FR) Olivier LE BIHAN (INERIS, FR) Robert MUIR (NANEUM, UK) Tinh NGUYEN (NIST, USA) Bernd NOWACK (EMPA, CH) Günter OBERDÖRSTER (U. ROCHESTER, USA) David PUI (U. MINNESOTA, USA) Michael RIEDIKER (IST, CH) Yves SAMSON (CEA, FR) Ken TAKEDA (U. TOKYO, JP) Olivier WITSCHGER (INRS, FR) The PDF contains a list of sponsor logos, the conference programme and planning documents.

  15. Strong Motion Recording in the United States

    NASA Astrophysics Data System (ADS)

    Archuleta, R. J.; Fletcher, J. B.; Shakal, A. F.

    2014-12-01

    The United States strong motion program began in 1932 when the Coast and Geodetic Survey (C&GS) installed eight strong motion accelerographs in California. During the March 1933 Long Beach earthquake, three of these produced the first strong motion records. With this success the C&GS expanded the number of accelerographs to 71 by 1964. With development of less expensive, mass-produced accelerographs the number of strong motion accelerographs expanded to ~575 by 1972. Responsibilities for operating the network and disseminating data were transferred to the National Oceanic and Atmospheric Administration in 1970 and then to the U.S. Geological Survey in 1973. In 1972 the California Legislature established the California Strong Motion Instrumentation Program (CSMIP). CSMIP operates accelerographs at 812 ground stations, with multi-channel accelerographs in 228 buildings, 125 lifelines and 37 geotechnical arrays, in California. The USGS and the ANSS effort operate accelerographs at 1584 ground stations, 96 buildings, 14 bridges, 70 dams, and 15 multi-channel geotechnical arrays. The USC Los Angeles array has 78 ground stations; UCSB operates 5 geotechnical arrays; other government and private institutions also operate accelerographs. Almost all accelerographs are now digital with a sampling rate of 200 Hz. Most of the strong motion data can be downloaded from the Center for Engineering Strong Motion Data (http://strongmotioncenter.org). As accelerographs have become more sophisticated, the concept of what constitutes strong motion has blurred because small earthquakes (M ~3) are well recorded on accelerometers as well as seismometers. However, when accelerations are over ~10%g and velocities over ~1 cm/s, the accelerometers remain on scale, providing the unclipped data necessary to analyze the ground motion and its consequences. Strong motion data are essential to the development of ground motion prediction equations, understanding structural response, performance

  16. In-Situ X-ray Spectroscopic Studies of the Fundamental Chemistry of Pb and Pb-Bi Corrosion Processes at High Temperatures: Development and Assessment of Composite Corrosion Resistant Materials.

    SciTech Connect

    Carlo Segre

    2009-12-30

    Over the course of this project, we have a number of accomplishments. The following list is presented as a summary statement for the project. Specific details from previous Quarterly Reports are given. (1) We established that it is possible to use EXAFS to study the interface layer between a material and the liquid Pb overlayer. We have discovered that molybdenum grows a selflimiting oxide layer which does not spall even at the highest temperatures studied. There have been 2 publications resulting from these studies. (2) We have fabricated a high temperature environmental chamber capable of extending the Pb overlayer studies by varying the incident x-ray beam angle to perform depth profiling of the Pb layer. This chamber will continue to be available to nuclear materials program researchers who wish to use the MRCAT beam line. (3) We have developed a collaboration with researchers at the Paul Scherrer Institute to study corrosion layers on zircalloy. One publication has resulted from this collaboration and another is in progress. (4) We have developed a collaboration with Prof. G.R. Odette of UCSB in which we studied the local structure of Ti and Y in nanoclusters found in oxygen dispersion strengthened steels. There are two publications in progress form this collaboration and we have extended the project to anomalous small angle x-ray scattering as well as EXAFS. (5) We have promoted the use of EXAFS for the study of nuclear materials to the community over the past 4 years and we have begun to see an increase in demand for EXAFS from the community at the MRCAT beam line. (6) This grant was instrumental in nucleating interest in establishing a new Collaborative Access Team at the Advanced Photon Source, the Nuclear and Radiological Research CAT (NRR-CAT). The co-PI (Jeff Terry) is the lead investigator on this project and it has been approved by the APS Scientific Advisory Committee for further planning. The status of the NRR-CAT project is being discussed in a

  17. New Tools for Viewing Spectrally and Temporally-Rich Remote Sensing Imagery

    NASA Astrophysics Data System (ADS)

    Bradley, E. S.; Toomey, M. P.; Roberts, D. A.; Still, C. J.

    2010-12-01

    High frequency, temporally extensive remote sensing datasets (GOES: 30 minutes, Santa Cruz Island webcam: nearly 5 years at every 10 min.) and airborne imaging spectrometry (AVIRIS with 224 spectral bands), present exciting opportunities for education, synthesis, and analysis. However, the large file volume / size can make holistic review and exploration difficult. In this research, we explore two options for visualization (1) a web-based portal for time-series analysis, PanOpt, and (2) Google Earth-based timestamped image overlays. PanOpt is an interactive website (http://zulu.geog.ucsb.edu/panopt/), which integrates high frequency (GOES) and multispectral (MODIS) satellite imagery with webcam ground-based repeat photography. Side-by-side comparison of satellite imagery with webcam images supports analysis of atmospheric and environmental phenomena. In this proof of concept, we have integrated four years of imagery for a multi-view FogCam on Santa Cruz Island off the coast of Southern California with two years of GOES-11 and four years of MODIS Aqua imagery subsets for the area (14,000 km2). From the PHP-based website, users can search the data (date, time of day, etc.) and specify timestep and display size; and then view the image stack as animations or in a matrix form. Extracted metrics for regions of interest (ROIs) can be viewed in different formats, including time-series and scatter plots. Through click and mouseover actions over the hyperlink-enabled data points, users can view the corresponding images. This directly melds the quantitative and qualitative aspects and could be particularly effective for both education as well as anomaly interpretation. We have also extended this project to Google Earth with timestamped GOES and MODIS image overlays, which can be controlled using the temporal slider and linked to a screen chart of ancillary meteorological data. The automated ENVI/IDL script for generating KMZ overlays was also applied for generating same

  18. Catalytic conversion of nonfood woody biomass solids to organic liquids.

    PubMed

    Barta, Katalin; Ford, Peter C

    2014-05-20

    This Account outlines recent efforts in our laboratories addressing a fundamental challenge of sustainability chemistry, the effective utilization of biomass for production of chemicals and fuels. Efficient methods for converting renewable biomass solids to chemicals and liquid fuels would reduce society's dependence on nonrenewable petroleum resources while easing the atmospheric carbon dioxide burden. The major nonfood component of biomass is lignocellulose, a matrix of the biopolymers cellulose, hemicellulose, and lignin. New approaches are needed to effect facile conversion of lignocellulose solids to liquid fuels and to other chemical precursors without the formation of intractable side products and with sufficient specificity to give economically sustainable product streams. We have devised a novel catalytic system whereby the renewable feedstocks cellulose, organosolv lignin, and even lignocellulose composites such as sawdust are transformed into organic liquids. The reaction medium is supercritical methanol (sc-MeOH), while the catalyst is a copper-doped porous metal oxide (PMO) prepared from inexpensive, Earth-abundant starting materials. This transformation occurs in a single stage reactor operating at 300-320 °C and 160-220 bar. The reducing equivalents for these transformations are derived by the reforming of MeOH (to H2 and CO), which thereby serves as a "liquid syngas" in the present case. Water generated by deoxygenation processes is quickly removed by the water-gas shift reaction. The Cu-doped PMO serves multiple purposes, catalyzing substrate hydrogenolysis and hydrogenation as well as the methanol reforming and shift reactions. This one-pot "UCSB process" is quantitative, giving little or no biochar residual. Provided is an overview of these catalysis studies beginning with reactions of the model compound dihydrobenzofuran that help define the key processes occurring. The initial step is phenyl-ether bond hydrogenolysis, and this is followed by

  19. Microbial decomposition of dead grassland roots and its influence on the carbon cycle under changing precipitation patterns

    NASA Astrophysics Data System (ADS)

    Becerra, C.; Schimel, J.

    2013-12-01

    Soil is the largest reservoir of organic carbon in terrestrial ecosystems and as such, represents a potential sink for carbon dioxide.The decomposition products of dead roots buried in the soil is a contributor to soil organic carbon. However, changing precipitation patterns may affect its fate by influencing the microbial community responsible for decomposing dead roots. To assess the impact of changing precipitation patterns, we constructed microcosms with grassland soil collected from the UCSB Sedgwick Reserve, an active and long-term research site, and dead roots from greenhouse-grown grass, Bromus diandrus. Microcosms were wetted continuously, every seven days, or every twenty days. Sets of microcosms were periodically deconstructed to assess the soil versus the roots-associated microbial community and its function. Differences in respiration rates of microcosms continuously wetted or wetted every 7 days versus microcosms wetted every 20 days existed for the first 70 days. After which, no differences in respiration rates were seen with microcosms containing roots and the no roots control. Relatedly, after a 70% roots mass loss by day 50, there was no difference in the respiration rate of microcosms containing roots and the no roots control. More than half of the roots mass loss had occurred by 30 days. By the end of the incubation period, the roots mass loss in continuously wet and 7-day wetted microcosms were over 80% compared to 67% for the microcosms wetted every 20 days. Microbial biomass in the soil were constant over time and showed no difference in treatment except with the no roots control during the first half of the incubation period. Hydrolytic enzyme activities (β-1,4-glucosidase; α-1,4-glucosidase; β-1,4-xylosidase; β-1,4-cellobiosidase) on the roots versus the soil attached to the roots were over an order greater and decreased faster with the exception of N-acetyl-glucosaminidase and acid phosphatase. Oxidative enzyme activities (phenol

  20. The nondestructive evaluation of thermal barrier coatings: Measurements of thermal properties and associated defects

    NASA Astrophysics Data System (ADS)

    Yu, Fengling

    2005-11-01

    Phase of thermal emission spectroscopy is developed to nondestructively determine the thermal properties of thermal barrier coatings (TBC). Harmonic heating of the coating is established using a CO2 laser. The phase of thermal emission is measured from the front surface as a function of laser frequency. A mathematical model is developed to describe the heat transport in the measurement and establish all important dependencies of the emission phase. Least square fitting of the experimental measurement using the model permits determination of the unknown properties of the TBC. Besides the thermal diffusivity of the coating, both the thermal conductivity and volumetric heat capacity of the coating can be determined simultaneously. A UCSB TBC deposited by electron-beam physical vapor deposition (EB-PVD) is measured and used to illustrate the measurement and analysis. Various TBC samples deposited by different deposition techniques with varying process parameters and materials are measured with phase of thermal emission spectroscopy. A set of TBC specimens deposited by EB-PVD with varying process parameters are measured. The influences of coating thickness, rotation rate, and deposition tilt on the thermal properties of coatings are studied. Another set of TBC samples deposited by directed vapor deposition (EB-DVD) with various processing parameters and different coating materials are also measured. The effects of rotation rate of the substrate and the substrate temperature for deposition are investigated. The thermal properties of two kinds of coating materials, 7wt% yittria, partially stabilized zirconia (7YSZ) and samarium zirconate (Sm2Zr2O7) are compared. Based on the phase of thermal emission spectroscopy, a surface area mapping method is developed for inspecting defects in TBCs non-destructively, which is desirable for monitoring the performance and predicting the failures of TBCs in service. Mapping the phase shift over a region of interest can be used to

  1. Charge Recombination, Transport Dynamics, and Interfacial Effects in Organic Solar Cells

    SciTech Connect

    Heeger, Alan; Bazan, Guillermo; Nguyen, Thuc-Quyen; Wudl, Fred

    2015-02-27

    are the following: • Photo-excitation of the donor (or the acceptor). • Charge transfer with holes in the donor domain and electrons in the acceptor domain. • Sweep-out to electrodes prior to recombination by the internal electric field. • Energy delivered to the external circuit. Each of these four steps was studied in detail using a wide variety of organic semiconductors with different molecular structures. This UC Santa Barbara group was the first to clarify the origin and the mechanism involved in the ultrafast charge transfer process. The ultrafast charge transfer (time scale approximately 100 times faster than the first step in the photo-synthesis of green plants) is the fundamental reason for the potential for high power conversion efficiency of sunlight to electricity from plastic solar cells. The UCSB group was the first to emphasize, clarify and demonstrate the need for sweep-out to electrodes prior to recombination by the internal electric field. The UCSB group was the first to synthesize small molecule organic semiconductors capable of high power conversion efficiencies. The results of this research were published in high impact peer-reviewed journals. Our published papers (40 in number) provide answers to fundamental questions that have been heavily discussed and debated in the field of Bulk Heterojunction Solar Cells; scientific questions that must be resolved before this technology can be ready for commercialization in large scale for production of renewable energy. Of the forty publications listed, nineteen were co-authored by two or more of the PIs, consistent with the multi-investigator approach described in the original proposal. The specific advantages of this “plastic” solar cell technology are the following: a. Manufacturing by low-cost printing technology using soluble organic semiconductors; this approach can be implemented in large scale by roll-to-roll printing on plastic substrates. b. Low energy cost in manufacturing; all steps

  2. PREFACE: Preface

    NASA Astrophysics Data System (ADS)

    Sathyaprakash, B. S.; Singh, Tejinder

    2014-03-01

    painstaking task of proofreading and copyediting the accepted papers. We also thank the SOC, and the Workshop Chairs for their help in putting together an excellent scientific programme, the LOC for the wonderful organization, and the referees of papers for their help in improving the quality of the papers. Finally, we would like to thank all the authors who have made the publication of these proceedings possible, through their contribution. B S Sathyaprakash and Tejinder P Singh Scientific Organizing Committee Pijushpani Bhattacharjee (SINP, India) J Richard Bond (CITA, Canada) Manuela Campanelli (RIT, USA) Debajyoti Choudhury (Delhi University, India) Richard Ellis (Caltech, USA) Gary Gibbons (DAMTP, UK) Pankaj Joshi (TIFR, India) Romesh Kaul (IMSc, India) Subhabrata Majumdar (TIFR, India) Don Marolf (UCSB, USA) Ramesh Narayan (CfA, Harvard University, USA) Lyman Page (Princeton University, USA) Misao Sasaki (YITP, Japan) B S Sathyaprakash (Cardiff University, UK) Ashoke Sen (HRI, India) Tarun Souradeep (IUCAA, India) [Chair] P S Sreekumar (ISRO, India) Alexei Starobinsky (Landau Institute, Russia) Sumati Surya (RRI, India) C S Unnikrishnan (TIFR, India) Spenta Wadia (TIFR, India) Local Organzing Committee Ghanashyam Date A Gopakumar Subhabrata Majumdar D Narasimha T P Singh (Chair) Supporting Staff V Chellathurai [Scientific Programmes Coordinator] Ashok Deshpande [Accounts Officer] Margaret D'Souza [Secretary] Shobha Jagtap [Secretary] Nishikant Kadam [Secretary] Vijay Kadam [Assistant] A list of participants is available in the PDF

  3. Physics-Based Spectra of Accretion Disks around Black Holes

    NASA Technical Reports Server (NTRS)

    Krolik, Julian H.

    2005-01-01

    The purpose of this grant was to begin the process of deriving the light output of accretion disks around black holes directly from the actual processes that inject heat into the accreting matter, rather than from guessed dependences of heating rate on physical parameters. At JHU, the effort has focussed so far on models of accretion onto "intermediate mass black holes", a possible class of black holes, examples of which may have recently been discovered in nearby galaxies. There, Krolik and his student (Yawei Hui) have computed stellar atmospheres for uniformly-heated disks around this class of black holes. Their models serve two purposes: they are the very first serious attempts to compute the spectrum from accreting black holes in this mass range; and a library of such models can be used later in this program as contrasts for those computed on the basis of real disk dynamics. The output from these local disk calculations has also been successfully coupled to a program that applies the appropriate relativistic transformations and computes photon trajectories in order to predict the spectrum received by observers located at different polar angles. The principal new result of these calculations is the discovery of potentially observable ionization edges of H-like C and O at frequencies near the peak in flux from these objects. Most of the grant money at UCSB was spent on supporting graduate student Shane Davis. In addition. some money was spent on supporting two other students: Ari Socrates (now a Hubble Fellow at Princeton), and Laura Melling. Davis spent the year constructing stellar atmosphere models of accretion disks appropriate for the high/soft (thermal) state of black hole X-ray binaries. As with AGN models published previously by our collaboration with NASA support. our models include a complete general relativistic treatment of both the disk structure and the propagation of photons from the disk to a distant observer. They also include all important

  4. Study of the variability of Atlantic Intertropical Convergence Zone using multivariate indices

    NASA Astrophysics Data System (ADS)

    Nóbile Tomaziello, A.; Gandu, A.; Carvalho, L. V.

    2013-05-01

    Ana Carolina Nóbile Tomaziello, Adilson Wagner Gandu Institute of Astronomy, Geophysics and Atmospheric Sciences, University of São Paulo, Brazil carolnobile@model.iag.usp.br; adwgandu@model.iag.usp.br Leila Maria Véspoli de Carvalho Department of Geography, University of California, Santa Barbara, United States leila@eri.ucsb.edu The variability of Atlantic Intertropical Convergence Zone (ITCZ) is studied using multivariate indices based on the first and second combined EOF (EOFc) of anomalies of zonal and meridional wind's components, specific humidity, and air temperature at 850 mb, and precipitation. The EOFc's spatial domain encompassed tropical Atlantic Ocean and part of Brazilian Northeast and western Africa. Silva and Carvalho (2007) described a similar index in order to characterize the South American monsoon. First and second modes of EOFc describe successfully ITCZ's main features. Composites for the percentile of 25% (75%) for EOFc-1 show convection (suppression), and easterly and south (westerly and north) wind anomalies in ITCZ. There are negative anomalies of humidity over central Brazil when there are positive ones over ITCZ, and vice-versa. For the second mode, composites for the percentile of 25% (75%) show convection (suppression), westerly and south (easterly and north) wind anomalies in ITCZ, and negative (positive) anomalies of temperature in tropical Atlantic. Negative (positive) anomalies of humidity in northern and northwestern South America, and central Brazil are accompanied by positive (negative) ones in tropical north Atlantic. Convergence (divergence) of meridional wind in tropical Atlantic is associated with divergence (convergence) over southern and part of southeastern Brazil. EOFc-2 illustrates a possible relationship between SACZ and ITCZ and also shows a Pacific-South America (PSA) like pattern teleconnecting Indian and Pacific Oceans to South America. The PSA-like wave train has opposite phases for percentiles of 25% and 75

  5. Electric conductivity for laboratory and field monitoring of induced partial saturation (IPS) in sands

    NASA Astrophysics Data System (ADS)

    Kazemiroodsari, Hadi

    implemented in the prepared specimen to validate the numerical simulation model and explore the use of conductivity probes to detect the transport of chemical solution, estimate degree of saturation achieved due to injection of chemical solution, and evaluate final zone of partial saturation. The conductivity probe and the simulation results agreed well. To study the effect of IPS on liquefaction response of the sand specimen, IPS was implemented in a large (2-story high) sand specimen prepared in the laminar box of NEES Buffalo and then the specimen was subjected to harmonic shaking. Electric conductivity probes were used in the specimen treatment by controlling the duration and spacing of injection of the chemical solution, in monitoring the transport of chemical solution, in the estimation of zone of partial saturation achieved, and in the estimation of degree of saturation achieved due to implementation of IPS. The conductivity probes indicated partial saturation of the specimen. The shaking tests results confirmed the partial saturation state of the sand specimen. In addition, to the laboratory works, electric conductivity probes were used in field implementation of IPS in a pilot test at the Wildlife Liquefaction Array (WLA) of NEES UCSB site. The conductivity probes in the field test helped decide the optimum injection pressure, the injection tube spacing, and the degree of saturation that could be achieved in the field. The various laboratory and field tests confirmed that electric conductivity and the probes devised and used can be invaluable in the implementation of IPS, by providing information regarding transport of the chemical solution, the spacing of injection tubes, duration of injection, and the zone and degree of partial saturation caused by IPS.

  6. Learning Science Process Through Data Exploration and Writing

    NASA Astrophysics Data System (ADS)

    Prothero, W. A.

    2007-12-01

    One of the most effective ways of teaching science process is to have students take part in the same activities that practicing scientists engage in. These activities include studying the current research in the field, discussing ideas with colleagues, formulating a research problem, making a proposal defining the problem and plan of attack, presenting and writing about the results of the study, and critically reviewing the work of others. An inquiry curriculum can use these activities to guide the scaffolding of assignments and learning experiences that help students learn science process. At UCSB, students in a large general education oceanography class use real Earth data to study plate tectonics, the Indian Monsoon, climate change, and the health of the world fisheries. The end product for each subject has been a science paper based on Earth data. Over a period of approximately 15 years, the scaffolding of activities to prepare each student for the written assignments has been modified and improved, in response to student feedback and their success with the assignments. I have found that the following resources and sequence of activities help the oceanography students write good science papers. 1. Lecture: motivation and the opportunity for feedback and questions. 2. Textbook: background information. It is also possible to get the information from the internet, but unless the scope of reading is strictly defined, students don't know when to stop reading and become unhappy. 3. Online assignments: automatically graded assignments that force the student to keep up with reading. 4. Questions of the day: in-class handouts, with diagrams that the students either complete, or answer questions about. They are handed in and tallied, but not graded. They also inform the instructor of misconceptions. 5. Thought questions: student answers are posted on a threaded discussion list, and are due prior to lecture. The answers provide instructor feedback and guide the lecture

  7. Preliminary results of field mapping of methane plumes offshore of Coal Oil Point, California with a RESON 7125 multibeam sonar in water-column mode

    NASA Astrophysics Data System (ADS)

    Finlayson, D. P.; Hatcher, G.; Lorenson, T. D.; Greinert, J.; Maillard, E.; Weirathmueller, M.; Leifer, I.

    2010-12-01

    From June 17 - 23 2010, the U. S. Geological Survey (USGS) in collaboration with the Bureau of Ocean Energy Management Regulation and Enforcement(BOEMRE), the Royal Netherlands Institute for Sea Research (NIOZ) , RESON Inc. and the University of California, Santa Barbara(UCSB) conducted a comprehensive marine-seep gas-plume mapping study offshore of Coal Oil Point, California. The ultimate goal of the experiment is to quantify the amount of methane emitted from natural seeps using multibeam sonar, with results calibrated using field measurements of aqueous and atmospheric methane in the seep fields. Success will lead to better estimates of natural marine methane contributions to the global methane budget. We mapped selected seeps, some twice, with a pole-mounted RESON 7125 multibeam with a 10-degree forward rake. Other equipment included a Benthos Stingray ROV equipped with high-definition video cameras and in situ gas sampling apparatus, Niskin bottles for water column sampling of dissolved methane, and a Picarro G1301 cavity ringdown spectrometer for mapping atmospheric methane concentrations. This paper focuses primarily on the data reduction and data visualization strategies employed while processing the more than 1.2 TB of raw water column data collected by the multibeam system over several high-output oil and gas seep areas. Water depths ranged from about 30 to 80m. Turnkey software solutions for processing these data are currently unavailable so most of the processing code was developed in-house by the USGS. The main challenge in processing the sonar water-column data is ray-tracing the large volume of data, with each ping containing more than 4500 times as many samples as a conventional multibeam ping. We employed two strategies to make processing tractable on conventional workstations: (1) decimate the raw data based on desired output resolution before ray-tracing; and (2) design the ray-tracing program to run in parallel on multi-core workstations

  8. Multibeam sonar mapping of Siberian seeps: Evaluating trends in methane flux from shallow sub-sea permafrost

    NASA Astrophysics Data System (ADS)

    Stubbs, Christopher; Leifer, Ira; Luyendyk, Bruce; Semiletov, Igor

    2010-05-01

    predicted to occur in the Arctic, there is a strong need for baseline measurements of ebullition to allow identification of emission trends. Baseline data were collected in Fall 2009 using multibeam sonar surveying techniques developed at UCSB. Data analysis has identified spatial and temporal controls on seepage bubble flux including geologic structure, and currents. Two sonar techniques were used in the ESAS. The first method used a pole-mounted 260 kHz 120° X 3° Imagenex Delta-T, which recorded two weeks of data continuously while steaming. The transducer swath was pitched forward of vertical to better discriminate vertical plume structures and the complete water-column returns were logged. A seabed-tracking depth window from each ping was summed vertically to account for the discontinuous nature of bubble plumes and lessen the representation of non-bubble sonar returns. Data were geo-rectified and mapped. Numerous bubble streams in shallow (6-20 m) water were identified using sonar in areas predicted to be underlain by permafrost. The second method used a vessel-tethered stationary frame on the seabed with the Delta-T sonar rotating continuously through 330° around a vertical axis with the swath arrayed vertically and the beams spanning from below the seabed to above the sea surface. This 4D method is a major improvement over multibeam sonar measurement in a horizontal plane, allowing for automated segregation between fish and seeps, improved gas flux calibration, current profile estimation, and measurement of wave characteristics, wave-driven bubble plumes, and bathymetric repeat mapping of the seabed.

  9. A Multi-Method Approach to Improving Monazite Geochronology: TIMS, LA-ICP-MS, SIMS and EPMA

    NASA Astrophysics Data System (ADS)

    Peterman, E. M.; Hacker, B. R.; Grove, M.; Gehrels, G. E.; Mattinson, J. M.

    2006-12-01

    A challenging aspect of monazite U-Th-Pb analysis by LA-ICPMS or other `in situ' methods relates to how to appropriately standardize measured inter-element ratios in this compositionally variable phase. A major impediment is the lack of widely available and compositionally appropriate standards. At UCSB, we have characterized three monazite samples: `Madagascar' (B. Schultz), `Jefferson County' (M. Bersch), and `Smithsonian' (Smithsonian Institution). Grains were analyzed by multicollector ID-TIMS in the static multi- collection mode to establish precise U-Pb ages. Inclusion free grains from each sample were fully digested in HCl and loaded onto filaments using silica gel. We obtained 206Pb/238U ages of 363.98 ± 0.74 Ma for the Jefferson County monazite, 511.25 ± 4.91 Ma for the Madagascar sample and 274.58 ± 0.58 Ma for the Smithsonian sample. Jefferson County and Madagascar are reversely discordant, which is partly attributed to `excess' 206Pb from the decay of 230Th. U, Th, and Pb isotopic measurements were undertaken by multicollector LA-ICPMS at UA. The He carrier gases have sufficiently low Hg abundance that any Hg in the 204 mass position was subtracted by measuring on-peak backgrounds prior to sample analysis. Using the well-characterized monazite sample `44069' (J. Aleinikoff) as a primary standard, we obtained 206Pb/238U of 365.5 ± 2.6 Ma for Jefferson County, 1416 ± 29 Ma for Madagascar, and 357.1 ± 4.9 Ma for Smithsonian. Measured Th-Pb ages were 360.0 ± 4.6 Ma, 1345 ± 39 Ma, and 262.1 ± 4.1 Ma respectively. Ion microprobe Th-Pb ages obtained at UCLA from the same materials were 411 ± 12 Ma, 571 ± 18 Ma, and 327 ± 16 Ma using 44069 as a standard. The discrepancies among U-Pb and Th-Pb ages measured with the three methods clearly indicates that we have much to learn regarding standard-based in situ analysis of monazite. To quantify polyatomic species interference on targeted masses, we analyzed a synthetic CePO4 on the LA-ICPMS at UA. Data

  10. Assessing the Efficacy of the Aerobic Methanotrophic Biofilter in Methane Hydrate Environments

    SciTech Connect

    Valentine, David

    2012-09-30

    In October 2008 the University of California at Santa Barbara (UCSB) initiated investigations of water column methane oxidation in methane hydrate environments, through a project funded by the National Energy Technology Laboratory (NETL) entitled: assessing the efficacy of the aerobic methanotrophic biofilter in methane hydrate environments. This Final Report describes the scientific advances and discoveries made under this award as well as the importance of these discoveries in the broader context of the research area. Benthic microbial mats inhabit the sea floor in areas where reduced chemicals such as sulfide reach the more oxidizing water that overlies the sediment. We set out to investigate the role that methanotrophs play in such mats at locations where methane reaches the sea floor along with sulfide. Mats were sampled from several seep environments and multiple sets were grown in-situ at a hydrocarbon seep in the Santa Barbara Basin. Mats grown in-situ were returned to the laboratory and used to perform stable isotope probing experiments in which they were treated with 13C-enriched methane. The microbial community was analyzed, demonstrating that three or more microbial groups became enriched in methane?s carbon: methanotrophs that presumably utilize methane directly, methylotrophs that presumably consume methanol excreted by the methanotrophs, and sulfide oxidizers that presumably consume carbon dioxide released by the methanotrophs and methylotrophs. Methanotrophs reached high relative abundance in mats grown on methane, but other bacterial processes include sulfide oxidation appeared to dominate mats, indicating that methanotrophy is not a dominant process in sustaining these benthic mats, but rather a secondary function modulated by methane availability. Methane that escapes the sediment in the deep ocean typically dissolved into the overlying water where it is available to methanotrophic bacteria. We set out to better understand the efficacy of this

  11. TeraShake-2: Next Steps

    NASA Astrophysics Data System (ADS)

    Minster, J.; Olsen, K.; Day, S.; Cui, Y.; Faerman, M.; Moore, R.; Okaya, D.; Jordan, T.; Archuleta, R.; Hu, Y.; Ely, G.

    2005-12-01

    The SCEC ITR collaboration achieved a series of earthquake simulations on the southern segment of the San Andreas fault that brought to light an heretofore unsuspected pattern of seismic hazard, linked to fault geometry, rupture directivity, and wave propagation through the three-dimensional SCEC Community velocity model. This set of simulations, labeled TeraShake-1 relied on a kinematic fault rupture model scaled from inversion results for the 1999 Denali earthquake. That model is quite severely constrained, and questions remain about the level of uncertainty we should attach to these results. We report on the next stage of development that incorporates a spontaneous rupture model, using one or more of several codes being compared as part of the SCEC spontaneous rupture mode validation effort. There exist about a dozen such codes. We are initially restricting our focus on four such codes: (1) the 2nd-order Dynamic Fault Model (DFM) FD code that has passed numerous tests; (2) the 4th order FD Anelastic Wave Propagation Model (AWM) code, used in the SCEC TeraShake-I and Cybershake projects; (3) the UCSB Finite Element spontaneous rupture and wave propagation code; (4) the SIO 'mimetic' Support-Operator Rupture Dynamic (SORD) code. All these have quite different levels of maturity. A major challenge is that the range of scales involved in such simulations is enormous: the inner scale associated with rupture characteristics is in the range of 1-100 meters, while the outer scale associated with geology, wave propagation, and hazard assessment reaches 600 kilometers. Time scales cover an equally broad range of magnitudes. This combination raises a numerical 'grand challenge' that pushes the limits of available computing systems. Additional considerations include desired capabilities to model nonplanar faults, and to include surface topography in the calculation. Recent SCEC research results show that such complications are indeed potentially important for accurate

  12. CEEM Final Technical Report

    SciTech Connect

    Bowers, John

    2014-11-26

    The mission of the Center for Energy Efficient Materials (CEEM) was to serve the Department of Energy and the nation as a center of excellence dedicated to advancing basic research in nano-structured materials and devices for applications to solar electricity, thermoelectric conversion of waste heat to electricity, and solidstate lighting. The foundation of CEEM was based on the unique capabilities of UCSB and its partner institutions to control, synthesize, characterize, model, and apply materials at the nanoscale for more efficient sustainable energy resources. This unique expertise was a key source of the synergy that unified the research of the Center. Although the Center’s focus was basic research, It’s longer-term objective has been to transfer new materials and devices into the commercial sector where they will have a substantial impact on the nation’s need for efficient sustainable energy resources. As one measure of the impact of the Center, two start-up companies were formed based on its research. In addition, Center participants published a total of 210 archival journal articles, of which 51 were exclusively sponsored by the DOE grant. The work of the Center was structured around four specific tasks: Organic Solar Cells, Solid-State Lighting, Thermoelectrics, and High Efficiency Multi-junction Photovoltaic devices. A brief summary of each follows – detailed descriptions are in Sections 4 & 5 of this report. Research supported through CEEM led to an important shift with respect to the choice of materials used for the fabrication of solution deposited organic solar cells. Solution deposition opens the opportunity to manufacture solar cells via economically-viable high throughput tools, such as roll to roll printing. Prior to CEEM, most organic semiconductors utilized for this purpose involved polymeric materials, which, although they can form thin films reliably, suffer from batch to batch variations due to the statistical nature of the chemical

  13. AAS 227: Day 4

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Editors Note:This week were at the 227th AAS Meeting in Kissimmee, FL. Along with several fellow authors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting at the end of each day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Welcome to Day 4 of the winter American Astronomical Society (AAS) meeting in Kissimmee! Several of us are attending the conference this year, and we will report highlights from each day here on astrobites. If youd like to see more timely updates during the day, we encourage you to follow @astrobites on twitter or search the #aas227 hashtag.Helen B. Warner Prize: Origins of Structure in Planetary Systems (by Erika Nesvold)Another excellent prize lecture started off todays sessions. The Helen B. Warner Prize is awarded for achievement in observational or theoretical astrophysics by a young researcher (no more than eight years after their Ph.D.). This years Warner Prize was presented to Ruth Murray-Clay of UC Santa Barbara. For her award lecture, Murray-Clay told us all about planetary system architecture: the number, masses, and orbits of planets in a given system.Ruth Murray-Clay [photo from http://web.physics.ucsb.edu/ ~murray/biocv.html]The underlying question motivating this type of research is: How rare is the Solar System? In other words, how likely is it that a given planetary system will have rocky planets close to their star, gas giants farther out, and ice giants at the outer reaches of the system? Answering this question will help us solve the physics problem of how and where planets form, and will also help us on our search for other planets like Earth.The data on exoplanet population from transit and radial velocity observations and from direct imaging tell us that our Solar System is not common (many systems we observe have much more eccentric gas giants), but that doesnt

  14. Scaling Mesa Indium Phosphide DHBTs to Record Bandwidths

    NASA Astrophysics Data System (ADS)

    Lobisser, Evan

    investigated with UCSB grown epitaxial material and the fabrication of transmission line model structures. Electron beam lithography processes were developed and employed for both emitter and base layers. Epitaxial designs were scaled and revised, and grown by a commercial vendor. These process developments are detailed in Chapter 3. Transistor electrical characteristics were measured using a semiconductor parameter analyzer at DC and network analyzers for RF measurements at frequencies up to 220 GHz. Both on- and off-wafer network analyzer calibration structures were designed and fabricated, and the calibration techniques were compared. New structures for transmission line model measurements of contact resistivity have been designed and used in the measurement of new ohmic contact processes. Measurement techniques are detailed in Chapter 4. Two transistor results are presented in Chapter 5. For each device, epitaxial designs are presented, and band diagrams, both without current flow and under peak bias conditions are shown. The processes used to fabricate each transistor are detailed. For the first result, referred to as DHBT 43, ftau = 360 GHz and fmax > 800 GHz was obtained with 200 nm wide emitter-base junctions and 150 nm thick collectors. For the second result, referred to as DHBT 60, ftau = 530 GHz and fmax = 750 GHz was obtained with 150 nm wide emitter-base junctions and 70 nm thick collectors. Both transistors feature a refractory emitter contact, and the second result uses electron-beam lithography to narrow the emitter-base and base-collector junction widths. DC measurements of common-emitter I-V curves and Gummel plots are used to extract device parameters like breakdown voltage, current gain, and base and collector ideality constants. On-wafer TLM structures are used to extract device base and collector resistance. S-parameter measurements at RF frequencies are used to extract cutoff frequencies ftau and fmax, as well as device parameters necessary to generate

  15. Preface: SciDAC 2009

    NASA Astrophysics Data System (ADS)

    Simon, Horst

    2009-07-01

    and posters goes to the teams of researchers, the success of this year's conference is due to the strong efforts and support from members of the 2009 SciDAC Program Committee and Organizing Committee, and I would like to extend my heartfelt thanks to them for helping to make the 2009 meeting the largest and most successful to date. Program Committee members were: David Bader, LLNL; Pete Beckman, ANL; John Bell, LBNL; John Boisseau, University of Texas; Paul Bonoli, MIT; Hank Childs, LBNL; Bill Collins, LBNL; Jim Davenport, BNL; David Dean, ORNL; Thom Dunning, NCSA; Peg Folta, LLNL; Glenn Hammond, PNNL; Maciej Haranczyk, LBNL; Robert Harrison, ORNL; Paul Hovland, ANL; Paul Kent, ORNL; Aram Kevorkian, SPAWAR; David Keyes, Columbia University; Kwok Ko, SLAC; Felice Lightstone, LLNL; Bob Lucas, ISI/USC; Paul Mackenzie, Fermilab; Tony Mezzacappa, ORNL; John Negele, MIT; Jeff Nichols, ORNL; Mike Norman, UCSD; Joe Oefelein, SNL; Jeanie Osburn, NRL; Peter Ostroumov, ANL; Valerio Pascucci, University of Utah; Ruth Pordes, Fermilab; Rob Ross, ANL; Nagiza Samatova, ORNL; Martin Savage, University of Washington; Tim Scheibe, PNNL; Ed Seidel, NSF; Arie Shoshani, LBNL; Rick Stevens, ANL; Bob Sugar, UCSB; Bill Tang, PPPL; Bob Wilhelmson, NCSA; Kathy Yelick, NERSC/LBNL; Dave Zachmann, Vista Computational Technology LLC. Organizing Committee members were: Communications: Jon Bashor, LBNL. Contracts/Logistics: Mary Spada and Cheryl Zidel, ANL. Posters: David Bailey, LBNL. Proceedings: John Hules, LBNL. Proceedings Database Developer: Beth Cerny Patino, ANL. Program Committee Liaison/Conference Web Site: Yeen Mankin, LBNL. Tutorials: David Skinner, NERSC/LBNL. Visualization Night: Hank Childs, LBNL; Valerio Pascucci, Chems Touati, Nathan Galli, and Erik Jorgensen, University of Utah. Again, my thanks to all. Horst Simon San Diego, California June 18, 2009

  16. PREFACE: Turbulent Mixing and Beyond Turbulent Mixing and Beyond

    NASA Astrophysics Data System (ADS)

    Abarzhi, Snezhana I.; Gauthier, Serge; Rosner, Robert

    2008-10-01

    ) Institute for Laser Engineering (ILE), Osaka, Japan (Division Head: Dr K Nishihara) Illinois Institute of Technology (IIT), Chicago, USA (College of Science and Letters, Department of Applied Mathematics: Dr S I Abarji) and thanks them for making this event possible. The Organizing Committee appreciates the assistance of Suzie Radosic (administrator and assistant, ICTP) Daniil Ilyin (web-master, Chicago) Elena Magnus (assistant, Chicago) We express our gratitude for the help with the Conference Program to the members of the Scientific Advisory Committee S I Abarzhi (The University of Chicago, Illinois Institute of Technology, USA) G Ahlers (University of California at Santa Barbara, USA) M J Andrews (Los Alamos National Laboratory, Texas A & M University, USA) S I Anisimov (Landau Institute for Theoretical Physics, Russia) E Bodenschatz (Max Plank Institute, Gottingen, Germany) S Dalziel (DAMTP, University of Cambridge, UK) R Ecke (Los Alamos National Laboratory, USA) H J Fernando (Arizona State University, USA) S Gauthier (Commissariat à l'Energie Atomique, France) G A Glatzmaier (University of California at Santa Cruz, USA) W A Goddard III (California Institute of Technology, USA) L P Kadanoff (The University of Chicago, USA) D Q Lamb (The University of Chicago, USA) D P Lathrop (University of Maryland, USA) S Lebedev (Imperial College, UK) P Manneville (Ecole Polytechnique, France) D I Meiron (California Institute of Technology, USA) H Nagib (Illinois Institute of Technology, Chicago, USA) J Niemela (International Center for Theoretical Physics, Italy) K Nishihara (Institute for Laser Engineering, Osaka, Japan) S A Orszag (Yale University, USA) E Ott (University of Maryland, USA) N Peters (RWTS, Aachen, Germany) S B Pope (Cornell, USA) B A Remington (Lawrence Livermore National Laboratory, USA) R Rosner (Argonne National Laboratory and The University of Chicago, USA) A Schmidt (Naval Research Laboratory, USA) K R Sreenivasan (International Centre for Theoretical Physics

  17. Preface: SciDAC 2008

    NASA Astrophysics Data System (ADS)

    Stevens, Rick

    2008-07-01

    Microsoft Research at a new conference facility in Redmond, Washington. Over 90 people attended the tutorials, which covered topics ranging from an introduction to BG/P programming to advanced numerical libraries. The SciDAC and INCITE programs and the DOE Office of Advanced Scientific Computing Research core program investments in applied mathematics, computer science, and computational and networking facilities provide a nearly optimum framework for advancing computational science for DOE's Office of Science. At a broader level this framework also is benefiting the entire American scientific enterprise. As we look forward, it is clear that computational approaches will play an increasingly significant role in addressing challenging problems in basic science, energy, and environmental research. It takes many people to organize and support the SciDAC conference, and I would like to thank as many of them as possible. The backbone of the conference is the technical program; and the task of selecting, vetting, and recruiting speakers is the job of the organizing committee. I thank the members of this committee for all the hard work and the many tens of conference calls that enabled a wonderful program to be assembled. This year the following people served on the organizing committee: Jim Ahrens, LANL; David Bader, LLNL; Bryan Barnett, Microsoft; Peter Beckman, ANL; Vincent Chan, GA; Jackie Chen, SNL; Lori Diachin, LLNL; Dan Fay, Microsoft; Ian Foster, ANL; Mark Gordon, Ames; Mohammad Khaleel, PNNL; David Keyes, Columbia University; Bob Lucas, University of Southern California; Tony Mezzacappa, ORNL; Jeff Nichols, ORNL; David Nowak, ANL; Michael Papka, ANL; Thomas Schultess, ORNL; Horst Simon, LBNL; David Skinner, LBNL; Panagiotis Spentzouris, Fermilab; Bob Sugar, UCSB; and Kathy Yelick, LBNL. I owe a special thanks to Mike Papka and Jim Ahrens for handling the electronic theater. I also thank all those who submitted videos. It was a highly successful experiment. Behind the

  18. From biologically-inspired physics to physics-inspired biology From biologically-inspired physics to physics-inspired biology

    NASA Astrophysics Data System (ADS)

    Kornyshev, Alexei A.

    2010-10-01

    job should be left with computers. No Bessel functions, please!' This point of view was advocated by my office mate at KITP, Rob Philips, Professor of Applied Physics and Molecular Biophysics at Caltech, who found his new love—biology: from solid state theory. We had heated arguments about it. And my strongest one was that it was the maths of the now famous paper by Cochran et al [1] that allowed Watson and Crick to decipher the DNA x-ray patterns of Rosalind Franklin. The CCV formula for the x-ray scattering intensity fully explained the structure of the famous cross of the scattering maxima on the (kz, K)-map, where kz and K are, respectively, the components of the scattering wave-vector transfer in the direction along the main axis of the columnar array of the DNA molecules and in the perpendicular plane. From the distance and the position of the darkest spots on that pattern it was possible to deduce that the studied DNA has a shape of a double helix, to find its radius, the width of the minor and major groove, the vertical rise between base pairs, and the helical pitch. There were still some features in that pattern which have not been noticed, which were only understood half a century later after the corresponding extension of the CCV theory [2, 3], but those were not essential for solving the structure of DNA itself at that time, but rather for the understanding of DNA-DNA interactions and their effect on more subtle aspects of DNA structure, which are an issue today. The 'Bessel function' was the key player in the CCV equation and the extensions that followed. Dogma 3:'This happened once. It is unlikely to ever happen again' (from a conversation with a respectable editor of a high-profile biological journal about the revolution made by physics in biology). This is a common opinion, at least in the biological community. Note, that of the four discoverers of the DNA structure, three were physicists and only Watson was a biologist, and the key secret in that

  19. High energy neutrinos from astrophysical accelerators of cosmic ray nuclei

    NASA Astrophysics Data System (ADS)

    Anchordoqui, Luis A.; Hooper, Dan; Sarkar, Subir; Taylor, Andrew M.

    2008-02-01

    .SteckerC.DoneM.H.SalamonP.SommersPhys. Rev. Lett.6619912697(Erratum-ibid. 69 (1992) 2738)F.W.SteckerPhys. Rev. D722005107301A.AtoyanC.D.DermerPhys. Rev. Lett.872001221102L.A.AnchordoquiH.GoldbergF.HalzenT.J.WeilerPhys. Lett. B6002004202E.WaxmanJ.N.BahcallPhys. Rev. Lett.7819972292C.D.DermerA.AtoyanPhys. Rev. Lett.912003071102D.GuettaD.HooperJ.Alvarez-MunizF.HalzenE.ReuveniAstropart. Phys.202004429J.Alvarez-MunizF.HalzenD.W.HooperPhys. Rev. D622000093015A.LoebE.WaxmanJCAP06052006003S. Inoue, G. Sigl, F. Miniati, E. Armengaud, arXiv:astro-ph/0701167.E.WaxmanJ.N.BahcallPhys. Rev. D591999023002Phys. Rev. D642001023002K.MannheimR.J.ProtheroeJ.P.RachenPhys. Rev. D632001023003arXiv:astro-ph/9908031M.AhlersL.A.AnchordoquiH.GoldbergF.HalzenA.RingwaldT.J.WeilerPhys. Rev. D722005023001E.WaxmanAstrophys. J.4521995L1Note that the neutrino spectral shape can deviate from that for protons if the Feynman plateau is not flat in pseudo-rapidity space;L.AnchordoquiH.GoldbergC.NunezPhys. Rev. D712005065014This is in fact suggested by Tevatron data;F.AbeCDF CollaborationPhys. Rev. D4119902330J.G.LearnedS.PakvasaAstropart. Phys.31995267F.HalzenD.SaltzbergPhys. Rev. Lett.8119984305J.F.BeacomN.F.BellD.HooperS.PakvasaT.J.WeilerPhys. Rev. D682003093005(Erratum-ibid. D 72 (2005) 019901)L.A.AnchordoquiH.GoldbergF.HalzenT.J.WeilerPhys. Lett. B593200442L.A.AnchordoquiH.GoldbergF.HalzenT.J.WeilerPhys. Lett. B621200518A.M.HillasAnn. Rev. Astron. Astrophys.221984425For a general discussion on the acceleration time-scale in these sources see, e.g.,D.F.TorresL.A.AnchordoquiRep. Prog. Phys.6720041663M.C.BegelmanB.RudakM.SikoraAstrophys. J.362199038M.J.ChodorowskiA.A.ZdziarskiM.SikoraAstrophys. J.4001992181S.MichalowskiD.AndrewsJ.EickmeyerT.GentileN.MistryR.TalmanK.UenoPhys. Rev. Lett.391977737J.L.PugetF.W.SteckerJ.H.BredekampAstrophys. J.2051976638D.HooperS.SarkarA.M.TaylorAstropart. Phys.272007199The non-thermal energy release in GRBs is much smaller than that output by AGN.P.L.BiermannP.A.StrittmatterAstrophys. J.3221987643R

  20. AAS 227: Day 4

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Editors Note:This week were at the 227th AAS Meeting in Kissimmee, FL. Along with several fellow authors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting at the end of each day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Welcome to Day 4 of the winter American Astronomical Society (AAS) meeting in Kissimmee! Several of us are attending the conference this year, and we will report highlights from each day here on astrobites. If youd like to see more timely updates during the day, we encourage you to follow @astrobites on twitter or search the #aas227 hashtag.Helen B. Warner Prize: Origins of Structure in Planetary Systems (by Erika Nesvold)Another excellent prize lecture started off todays sessions. The Helen B. Warner Prize is awarded for achievement in observational or theoretical astrophysics by a young researcher (no more than eight years after their Ph.D.). This years Warner Prize was presented to Ruth Murray-Clay of UC Santa Barbara. For her award lecture, Murray-Clay told us all about planetary system architecture: the number, masses, and orbits of planets in a given system.Ruth Murray-Clay [photo from http://web.physics.ucsb.edu/ ~murray/biocv.html]The underlying question motivating this type of research is: How rare is the Solar System? In other words, how likely is it that a given planetary system will have rocky planets close to their star, gas giants farther out, and ice giants at the outer reaches of the system? Answering this question will help us solve the physics problem of how and where planets form, and will also help us on our search for other planets like Earth.The data on exoplanet population from transit and radial velocity observations and from direct imaging tell us that our Solar System is not common (many systems we observe have much more eccentric gas giants), but that doesnt