Science.gov

Sample records for abstract background approximately

  1. Nonsymbolic, Approximate Arithmetic in Children: Abstract Addition Prior to Instruction

    ERIC Educational Resources Information Center

    Barth, Hilary; Beckmann, Lacey; Spelke, Elizabeth S.

    2008-01-01

    Do children draw upon abstract representations of number when they perform approximate arithmetic operations? In this study, kindergarten children viewed animations suggesting addition of a sequence of sounds to an array of dots, and they compared the sum to a second dot array that differed from the sum by 1 of 3 ratios. Children performed this…

  2. Reappraising Abstract Paintings after Exposure to Background Information

    PubMed Central

    Park, Seongmin A.; Yun, Kyongsik; Jeong, Jaeseung

    2015-01-01

    Can knowledge help viewers when they appreciate an artwork? Experts’ judgments of the aesthetic value of a painting often differ from the estimates of naïve viewers, and this phenomenon is especially pronounced in the aesthetic judgment of abstract paintings. We compared the changes in aesthetic judgments of naïve viewers while they were progressively exposed to five pieces of background information. The participants were asked to report their aesthetic judgments of a given painting after each piece of information was presented. We found that commentaries by the artist and a critic significantly increased the subjective aesthetic ratings. Does knowledge enable experts to attend to the visual features in a painting and to link it to the evaluative conventions, thus potentially causing different aesthetic judgments? To investigate whether a specific pattern of attention is essential for the knowledge-based appreciation, we tracked the eye movements of subjects while viewing a painting with a commentary by the artist and with a commentary by a critic. We observed that critics’ commentaries directed the viewers’ attention to the visual components that were highly relevant to the presented commentary. However, attention to specific features of a painting was not necessary for increasing the subjective aesthetic judgment when the artists’ commentary was presented. Our results suggest that at least two different cognitive mechanisms may be involved in knowledge- guided aesthetic judgments while viewers reappraise a painting. PMID:25945789

  3. COSMIC MICROWAVE BACKGROUND LIKELIHOOD APPROXIMATION FOR BANDED PROBABILITY DISTRIBUTIONS

    SciTech Connect

    Gjerløw, E.; Mikkelsen, K.; Eriksen, H. K.; Næss, S. K.; Seljebotn, D. S.; Górski, K. M.; Huey, G.; Jewell, J. B.; Rocha, G.; Wehus, I. K.

    2013-11-10

    We investigate sets of random variables that can be arranged sequentially such that a given variable only depends conditionally on its immediate predecessor. For such sets, we show that the full joint probability distribution may be expressed exclusively in terms of uni- and bivariate marginals. Under the assumption that the cosmic microwave background (CMB) power spectrum likelihood only exhibits correlations within a banded multipole range, Δl{sub C}, we apply this expression to two outstanding problems in CMB likelihood analysis. First, we derive a statistically well-defined hybrid likelihood estimator, merging two independent (e.g., low- and high-l) likelihoods into a single expression that properly accounts for correlations between the two. Applying this expression to the Wilkinson Microwave Anisotropy Probe (WMAP) likelihood, we verify that the effect of correlations on cosmological parameters in the transition region is negligible in terms of cosmological parameters for WMAP; the largest relative shift seen for any parameter is 0.06σ. However, because this may not hold for other experimental setups (e.g., for different instrumental noise properties or analysis masks), but must rather be verified on a case-by-case basis, we recommend our new hybridization scheme for future experiments for statistical self-consistency reasons. Second, we use the same expression to improve the convergence rate of the Blackwell-Rao likelihood estimator, reducing the required number of Monte Carlo samples by several orders of magnitude, and thereby extend it to high-l applications.

  4. AN EFFICIENT APPROXIMATION TO THE LIKELIHOOD FOR GRAVITATIONAL WAVE STOCHASTIC BACKGROUND DETECTION USING PULSAR TIMING DATA

    SciTech Connect

    Ellis, J. A.; Siemens, X.; Van Haasteren, R.

    2013-05-20

    Direct detection of gravitational waves by pulsar timing arrays will become feasible over the next few years. In the low frequency regime (10{sup -7} Hz-10{sup -9} Hz), we expect that a superposition of gravitational waves from many sources will manifest itself as an isotropic stochastic gravitational wave background. Currently, a number of techniques exist to detect such a signal; however, many detection methods are computationally challenging. Here we introduce an approximation to the full likelihood function for a pulsar timing array that results in computational savings proportional to the square of the number of pulsars in the array. Through a series of simulations we show that the approximate likelihood function reproduces results obtained from the full likelihood function. We further show, both analytically and through simulations, that, on average, this approximate likelihood function gives unbiased parameter estimates for astrophysically realistic stochastic background amplitudes.

  5. Strongly-local reductions and the complexity/efficient approximability of algebra and optimization on abstract algebraic structures

    SciTech Connect

    Hunt, H. B.; Marathe, M. V.; Stearns, R. E.

    2001-01-01

    We demonstrate how the concepts of algebraic representability and strongly-local reductions developed here and in [HSM00] can be used to characterize the computational complexity/efficient approximability of a number of basic problems and their variants, on various abstract algebraic structures F. These problems include the following: (1) A1gebra:Determine the solvability, unique solvability, number of solutions, etc., of a system of equations on F. Determine the equivalence of two formulas or straight-line programs on F. 2. 0ptimization:Let {epsilon} > 0. (a) Determine the maximum number of simultaneously satisfiable equations in a system of equations on F; or approximate this number within a multiplicative factor of n{sup {epsilon}}. (b) Determine the maximum value of an objective function subject to satisfiable algebraically expressed constraints on F; or approximate this maximum value within a multiplicative factor of n{sup {epsilon}}. (c) Given a formula or straight-line program, find a minimum size equivalent formula or straightline program; or find an equivalent formula or straight-line program of size {le} f (minimum). Both finite and infinite algebraic structures are considered. These finite structures include all finite nondegenerate lattices and all finite rings or semi-rings with a nonzero element idempotent under multiplication (e.g. all non-degenerate finite unitary rings or semi-rings); and these infinite structures include the natural numbers, integers, real numbers, various algebras on these structures, all ordered rings, many cancellative semi-rings, and all infinite lattices with two elements a,b such that a is covered by b. Our results significantly extend a number of results by Ladner [La89], Condon, et. al. [CF+93], Khanna, et.al [KSW97], Cr951 and Zuckerman [Zu93] on the complexity and approximbaility of combinatorial problems.

  6. Experiment-specific cosmic microwave background calculations made easier - Approximation formula for smoothed delta T/T windows

    NASA Technical Reports Server (NTRS)

    Gorski, Krzysztof M.

    1993-01-01

    Simple and easy to implement elementary function approximations are introduced to the spectral window functions needed in calculations of model predictions of the cosmic microwave backgrond (CMB) anisotropy. These approximations allow the investigator to obtain model delta T/T predictions in terms of single integrals over the power spectrum of cosmological perturbations and to avoid the necessity of performing the additional integrations. The high accuracy of these approximations is demonstrated here for the CDM theory-based calculations of the expected delta T/T signal in several experiments searching for the CMB anisotropy.

  7. Abstract Painting

    ERIC Educational Resources Information Center

    Henkes, Robert

    1978-01-01

    Abstract art provokes numerous interpretations, and as many misunderstandings. The adolescent reaction is no exception. The procedure described here can help the student to understand the abstract from at least one direction. (Author/RK)

  8. Path integral calculation of thermal rate constants within the quantum instanton approximation: Application to the H+CH4-->H2+CH3 hydrogen abstraction reaction in full Cartesian space

    NASA Astrophysics Data System (ADS)

    Zhao, Yi; Yamamoto, Takeshi; Miller, William H.

    2004-02-01

    The quantum instanton approximation for thermal rate constants of chemical reactions [Miller, Zhao, Ceotto, and Yang, J. Chem. Phys. 119, 1329 (2003)], which is modeled after the earlier semiclassical instanton approach, is applied to the hydrogen abstraction reaction from methane by a hydrogen atom, H+CH4→H2+CH3, using a modified and recalibrated version of the Jordan-Gilbert potential surface. The quantum instanton rate is evaluated using path integral Monte Carlo approaches based on the recently proposed implementation schemes [Yamamoto and Miller, J. Chem. Phys. 120, 3086 (2004)]. The calculations were carried out using the Cartesian coordinates of all the atoms (thus involving 18 degrees of freedom), thereby taking explicit account of rotational effects of the whole system and also allowing the equivalent treatment of the four methane hydrogens. To achieve such a treatment, we present extended forms of the path integral estimators for relevant quantities that may be used for general N-atom systems with any generalized reaction coordinates. The quantum instanton rates thus obtained for the temperature range T=200-2000 K show good agreement with available experimental data, which gives support to the accuracy of the underlying potential surface used.

  9. Path integral calculation of thermal rate constants within the quantum instanton approximation: application to the H + CH4 --> H2 + CH3 hydrogen abstraction reaction in full Cartesian space.

    PubMed

    Zhao, Yi; Yamamoto, Takeshi; Miller, William H

    2004-02-15

    The quantum instanton approximation for thermal rate constants of chemical reactions [Miller, Zhao, Ceotto, and Yang, J. Chem. Phys. 119, 1329 (2003)], which is modeled after the earlier semiclassical instanton approach, is applied to the hydrogen abstraction reaction from methane by a hydrogen atom, H + CH4 --> H2 + CH3, using a modified and recalibrated version of the Jordan-Gilbert potential surface. The quantum instanton rate is evaluated using path integral Monte Carlo approaches based on the recently proposed implementation schemes [Yamamoto and Miller, J. Chem. Phys. 120, 3086 (2004)]. The calculations were carried out using the Cartesian coordinates of all the atoms (thus involving 18 degrees of freedom), thereby taking explicit account of rotational effects of the whole system and also allowing the equivalent treatment of the four methane hydrogens. To achieve such a treatment, we present extended forms of the path integral estimators for relevant quantities that may be used for general N-atom systems with any generalized reaction coordinates. The quantum instanton rates thus obtained for the temperature range T = 200-2000 K show good agreement with available experimental data, which gives support to the accuracy of the underlying potential surface used. PMID:15268462

  10. Abstract Constructions.

    ERIC Educational Resources Information Center

    Pietropola, Anne

    1998-01-01

    Describes a lesson designed to culminate a year of eighth-grade art classes in which students explore elements of design and space by creating 3-D abstract constructions. Outlines the process of using foam board and markers to create various shapes and optical effects. (DSK)

  11. INVENTORY ABSTRACTION

    SciTech Connect

    G. Ragan

    2001-12-19

    The purpose of the inventory abstraction, which has been prepared in accordance with a technical work plan (CRWMS M&O 2000e for ICN 02 of the present analysis, and BSC 2001e for ICN 03 of the present analysis), is to: (1) Interpret the results of a series of relative dose calculations (CRWMS M&O 2000c, 2000f). (2) Recommend, including a basis thereof, a set of radionuclides that should be modeled in the Total System Performance Assessment in Support of the Site Recommendation (TSPA-SR) and the Total System Performance Assessment in Support of the Final Environmental Impact Statement (TSPA-FEIS). (3) Provide initial radionuclide inventories for the TSPA-SR and TSPA-FEIS models. (4) Answer the U.S. Nuclear Regulatory Commission (NRC)'s Issue Resolution Status Report ''Key Technical Issue: Container Life and Source Term'' (CLST IRSR) key technical issue (KTI): ''The rate at which radionuclides in SNF [spent nuclear fuel] are released from the EBS [engineered barrier system] through the oxidation and dissolution of spent fuel'' (NRC 1999, Subissue 3). The scope of the radionuclide screening analysis encompasses the period from 100 years to 10,000 years after the potential repository at Yucca Mountain is sealed for scenarios involving the breach of a waste package and subsequent degradation of the waste form as required for the TSPA-SR calculations. By extending the time period considered to one million years after repository closure, recommendations are made for the TSPA-FEIS. The waste forms included in the inventory abstraction are Commercial Spent Nuclear Fuel (CSNF), DOE Spent Nuclear Fuel (DSNF), High-Level Waste (HLW), naval Spent Nuclear Fuel (SNF), and U.S. Department of Energy (DOE) plutonium waste. The intended use of this analysis is in TSPA-SR and TSPA-FEIS. Based on the recommendations made here, models for release, transport, and possibly exposure will be developed for the isotopes that would be the highest contributors to the dose given a release to the

  12. Water reuse. [Lead abstract

    SciTech Connect

    Middlebrooks, E.J.

    1982-01-01

    Separate abstracts were prepared for the 31 chapters of this book which deals with all aspects of wastewater reuse. Design data, case histories, performance data, monitoring information, health information, social implications, legal and organizational structures, and background information needed to analyze the desirability of water reuse are presented. (KRM)

  13. EBS Radionuclide Transport Abstraction

    SciTech Connect

    J. Prouty

    2006-07-14

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  14. Approximation, abstraction and decomposition in search and optimization

    NASA Technical Reports Server (NTRS)

    Ellman, Thomas

    1992-01-01

    In this paper, I discuss four different areas of my research. One portion of my research has focused on automatic synthesis of search control heuristics for constraint satisfaction problems (CSPs). I have developed techniques for automatically synthesizing two types of heuristics for CSPs: Filtering functions are used to remove portions of a search space from consideration. Another portion of my research is focused on automatic synthesis of hierarchic algorithms for solving constraint satisfaction problems (CSPs). I have developed a technique for constructing hierarchic problem solvers based on numeric interval algebra. Another portion of my research is focused on automatic decomposition of design optimization problems. We are using the design of racing yacht hulls as a testbed domain for this research. Decomposition is especially important in the design of complex physical shapes such as yacht hulls. Another portion of my research is focused on intelligent model selection in design optimization. The model selection problem results from the difficulty of using exact models to analyze the performance of candidate designs.

  15. Abstraction in perceptual symbol systems.

    PubMed Central

    Barsalou, Lawrence W

    2003-01-01

    After reviewing six senses of abstraction, this article focuses on abstractions that take the form of summary representations. Three central properties of these abstractions are established: ( i ) type-token interpretation; (ii) structured representation; and (iii) dynamic realization. Traditional theories of representation handle interpretation and structure well but are not sufficiently dynamical. Conversely, connectionist theories are exquisitely dynamic but have problems with structure. Perceptual symbol systems offer an approach that implements all three properties naturally. Within this framework, a loose collection of property and relation simulators develops to represent abstractions. Type-token interpretation results from binding a property simulator to a region of a perceived or simulated category member. Structured representation results from binding a configuration of property and relation simulators to multiple regions in an integrated manner. Dynamic realization results from applying different subsets of property and relation simulators to category members on different occasions. From this standpoint, there are no permanent or complete abstractions of a category in memory. Instead, abstraction is the skill to construct temporary online interpretations of a category's members. Although an infinite number of abstractions are possible, attractors develop for habitual approaches to interpretation. This approach provides new ways of thinking about abstraction phenomena in categorization, inference, background knowledge and learning. PMID:12903648

  16. Piaget on Abstraction.

    ERIC Educational Resources Information Center

    Moessinger, Pierre; Poulin-Dubois, Diane

    1981-01-01

    Reviews and discusses Piaget's recent work on abstract reasoning. Piaget's distinction between empirical and reflective abstraction is presented; his hypotheses are considered to be metaphorical. (Author/DB)

  17. Abstract Expressionism. Clip and Save.

    ERIC Educational Resources Information Center

    Hubbard, Guy

    2002-01-01

    Provides information on the art movement, Abstract Expressionism, and includes learning activities. Focuses on the artist Jackson Pollock, offering a reproduction of his artwork, "Convergence: Number 10." Includes background information on the life and career of Pollock and a description of the included artwork. (CMK)

  18. EBS Radionuclide Transport Abstraction

    SciTech Connect

    J.D. Schreiber

    2005-08-25

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers

  19. Annual Conference Abstracts

    ERIC Educational Resources Information Center

    Engineering Education, 1975

    1975-01-01

    Papers abstracted represent those submitted to the distribution center at the 83rd American Society for Engineering Education Convention. Abstracts are grouped under headings corresponding to the main topic of the paper. (Editor/CP)

  20. Abstraction and Consolidation

    ERIC Educational Resources Information Center

    Monaghan, John; Ozmantar, Mehmet Fatih

    2006-01-01

    The framework for this paper is a recently developed theory of abstraction in context. The paper reports on data collected from one student working on tasks concerned with absolute value functions. It examines the relationship between mathematical constructions and abstractions. It argues that an abstraction is a consolidated construction that can…

  1. Automated Supernova Discovery (Abstract)

    NASA Astrophysics Data System (ADS)

    Post, R. S.

    2015-12-01

    (Abstract only) We are developing a system of robotic telescopes for automatic recognition of Supernovas as well as other transient events in collaboration with the Puckett Supernova Search Team. At the SAS2014 meeting, the discovery program, SNARE, was first described. Since then, it has been continuously improved to handle searches under a wide variety of atmospheric conditions. Currently, two telescopes are used to build a reference library while searching for PSN with a partial library. Since data is taken every night without clouds, we must deal with varying atmospheric and high background illumination from the moon. Software is configured to identify a PSN, reshoot for verification with options to change the run plan to acquire photometric or spectrographic data. The telescopes are 24-inch CDK24, with Alta U230 cameras, one in CA and one in NM. Images and run plans are sent between sites so the CA telescope can search while photometry is done in NM. Our goal is to find bright PSNs with magnitude 17.5 or less which is the limit of our planned spectroscopy. We present results from our first automated PSN discoveries and plans for PSN data acquisition.

  2. Abstraction and Problem Reformulation

    NASA Technical Reports Server (NTRS)

    Giunchiglia, Fausto

    1992-01-01

    In work done jointly with Toby Walsh, the author has provided a sound theoretical foundation to the process of reasoning with abstraction (GW90c, GWS9, GW9Ob, GW90a). The notion of abstraction formalized in this work can be informally described as: (property 1), the process of mapping a representation of a problem, called (following historical convention (Sac74)) the 'ground' representation, onto a new representation, called the 'abstract' representation, which, (property 2) helps deal with the problem in the original search space by preserving certain desirable properties and (property 3) is simpler to handle as it is constructed from the ground representation by "throwing away details". One desirable property preserved by an abstraction is provability; often there is a relationship between provability in the ground representation and provability in the abstract representation. Another can be deduction or, possibly inconsistency. By 'throwing away details' we usually mean that the problem is described in a language with a smaller search space (for instance a propositional language or a language without variables) in which formulae of the abstract representation are obtained from the formulae of the ground representation by the use of some terminating rewriting technique. Often we require that the use of abstraction results in more efficient .reasoning. However, it might simply increase the number of facts asserted (eg. by allowing, in practice, the exploration of deeper search spaces or by implementing some form of learning). Among all abstractions, three very important classes have been identified. They relate the set of facts provable in the ground space to those provable in the abstract space. We call: TI abstractions all those abstractions where the abstractions of all the provable facts of the ground space are provable in the abstract space; TD abstractions all those abstractions wllere the 'unabstractions' of all the provable facts of the abstract space are

  3. Abstraction in mathematics.

    PubMed

    Ferrari, Pier Luigi

    2003-07-29

    Some current interpretations of abstraction in mathematical settings are examined from different perspectives, including history and learning. It is argued that abstraction is a complex concept and that it cannot be reduced to generalization or decontextualization only. In particular, the links between abstraction processes and the emergence of new objects are shown. The role that representations have in abstraction is discussed, taking into account both the historical and the educational perspectives. As languages play a major role in mathematics, some ideas from functional linguistics are applied to explain to what extent mathematical notations are to be considered abstract. Finally, abstraction is examined from the perspective of mathematics education, to show that the teaching ideas resulting from one-dimensional interpretations of abstraction have proved utterly unsuccessful. PMID:12903658

  4. Loving Those Abstracts

    ERIC Educational Resources Information Center

    Stevens, Lori

    2004-01-01

    The author describes a lesson she did on abstract art with her high school art classes. She passed out a required step-by-step outline of the project process. She asked each of them to look at abstract art. They were to list five or six abstract artists they thought were interesting, narrow their list down to the one most personally intriguing,…

  5. Community Development Abstracts.

    ERIC Educational Resources Information Center

    Agency for International Development (Dept. of State), Washington, DC.

    This volume of 1,108 abstracts summarizes the majority of important works on community development during the last ten years. Part I contains abstracts of periodical literature and is classified into 19 sections, including general history, communications, community and area studies, decision-making, leadership, migration and settlement, social…

  6. Leadership Abstracts, Volume 10.

    ERIC Educational Resources Information Center

    Milliron, Mark D., Ed.

    1997-01-01

    The abstracts in this series provide brief discussions of issues related to leadership, administration, professional development, technology, and education in community colleges. Volume 10 for 1997 contains the following 12 abstracts: (1) "On Community College Renewal" (Nathan L. Hodges and Mark D. Milliron); (2) "The Community College Niche in a…

  7. Has Abstractness Been Resolved?

    ERIC Educational Resources Information Center

    Al-Omoush, Ahmad

    1989-01-01

    A discussion focusing on the abstractness of analysis in phonology, debated since the 1960s, describes the issue, reviews the literature on the subject, cites specific natural language examples, and examines the extent to which the issue has been resolved. An underlying representation is said to be abstract if it is different from the derived one,…

  8. Designing for Mathematical Abstraction

    ERIC Educational Resources Information Center

    Pratt, Dave; Noss, Richard

    2010-01-01

    Our focus is on the design of systems (pedagogical, technical, social) that encourage mathematical abstraction, a process we refer to as "designing for abstraction." In this paper, we draw on detailed design experiments from our research on children's understanding about chance and distribution to re-present this work as a case study in designing…

  9. Knowledge-Based Abstracting.

    ERIC Educational Resources Information Center

    Black, William J.

    1990-01-01

    Discussion of automatic abstracting of technical papers focuses on a knowledge-based method that uses two sets of rules. Topics discussed include anaphora; text structure and discourse; abstracting techniques, including the keyword method and the indicator phrase method; and tools for text skimming. (27 references) (LRW)

  10. Leadership Abstracts, 1995.

    ERIC Educational Resources Information Center

    Johnson, Larry, Ed.

    1995-01-01

    The abstracts in this series provide two-page discussions of issues related to leadership, administration, and teaching in community colleges. The 12 abstracts for Volume 8, 1995, are: (1) "Redesigning the System To Meet the Workforce Training Needs of the Nation," by Larry Warford; (2) "The College President, the Board, and the Board Chair: A…

  11. Paper Abstract Animals

    ERIC Educational Resources Information Center

    Sutley, Jane

    2010-01-01

    Abstraction is, in effect, a simplification and reduction of shapes with an absence of detail designed to comprise the essence of the more naturalistic images being depicted. Without even intending to, young children consistently create interesting, and sometimes beautiful, abstract compositions. A child's creations, moreover, will always seem to…

  12. Is It Really Abstract?

    ERIC Educational Resources Information Center

    Kernan, Christine

    2011-01-01

    For this author, one of the most enjoyable aspects of teaching elementary art is the willingness of students to embrace the different styles of art introduced to them. In this article, she describes a project that allows upper-elementary students to learn about abstract art and the lives of some of the master abstract artists, implement the idea…

  13. Journalism Abstracts. Vol. 15.

    ERIC Educational Resources Information Center

    Popovich, Mark N., Ed.

    This book, the fifteenth volume of an annual publication, contains 373 abstracts of 52 doctoral and 321 master's theses from 50 colleges and universities. The abstracts are arranged alphabetically by author, with the doctoral dissertations appearing first. These cover such topics as advertising, audience analysis, content analysis of news issues…

  14. Leadership Abstracts, 1996.

    ERIC Educational Resources Information Center

    Johnson, Larry, Ed.

    1996-01-01

    The abstracts in this series provide two-page discussions of issues related to leadership, administration, professional development, technology, and education in community colleges. Volume 9 for 1996 includes the following 12 abstracts: (1) "Tech-Prep + School-To-Work: Working Together To Foster Educational Reform," (Roderick F. Beaumont); (2)…

  15. Mathematical Abstraction through Scaffolding

    ERIC Educational Resources Information Center

    Ozmantar, Mehmet Fatih; Roper, Tom

    2004-01-01

    This paper examines the role of scaffolding in the process of abstraction. An activity-theoretic approach to abstraction in context is taken. This examination is carried out with reference to verbal protocols of two 17 year-old students working together on a task connected to sketching the graph of |f|x|)|. Examination of the data suggests that…

  16. Abstract coherent categories.

    PubMed

    Rehder, B; Ross, B H

    2001-09-01

    Many studies have demonstrated the importance of the knowledge that interrelates features in people's mental representation of categories and that makes our conception of categories coherent. This article focuses on abstract coherent categories, coherent categories that are also abstract because they are defined by relations independently of any features. Four experiments demonstrate that abstract coherent categories are learned more easily than control categories with identical features and statistical structure, and also that participants induced an abstract representation of the category by granting category membership to exemplars with completely novel features. The authors argue that the human conceptual system is heavily populated with abstract coherent concepts, including conceptions of social groups, societal institutions, legal, political, and military scenarios, and many superordinate categories, such as classes of natural kinds. PMID:11550753

  17. Abstract Datatypes in PVS

    NASA Technical Reports Server (NTRS)

    Owre, Sam; Shankar, Natarajan

    1997-01-01

    PVS (Prototype Verification System) is a general-purpose environment for developing specifications and proofs. This document deals primarily with the abstract datatype mechanism in PVS which generates theories containing axioms and definitions for a class of recursive datatypes. The concepts underlying the abstract datatype mechanism are illustrated using ordered binary trees as an example. Binary trees are described by a PVS abstract datatype that is parametric in its value type. The type of ordered binary trees is then presented as a subtype of binary trees where the ordering relation is also taken as a parameter. We define the operations of inserting an element into, and searching for an element in an ordered binary tree; the bulk of the report is devoted to PVS proofs of some useful properties of these operations. These proofs illustrate various approaches to proving properties of abstract datatype operations. They also describe the built-in capabilities of the PVS proof checker for simplifying abstract datatype expressions.

  18. Abstract Interpreters for Free

    NASA Astrophysics Data System (ADS)

    Might, Matthew

    In small-step abstract interpretations, the concrete and abstract semantics bear an uncanny resemblance. In this work, we present an analysis-design methodology that both explains and exploits that resemblance. Specifically, we present a two-step method to convert a small-step concrete semantics into a family of sound, computable abstract interpretations. The first step re-factors the concrete state-space to eliminate recursive structure; this refactoring of the state-space simultaneously determines a store-passing-style transformation on the underlying concrete semantics. The second step uses inference rules to generate an abstract state-space and a Galois connection simultaneously. The Galois connection allows the calculation of the "optimal" abstract interpretation. The two-step process is unambiguous, but nondeterministic: at each step, analysis designers face choices. Some of these choices ultimately influence properties such as flow-, field- and context-sensitivity. Thus, under the method, we can give the emergence of these properties a graph-theoretic characterization. To illustrate the method, we systematically abstract the continuation-passing style lambda calculus to arrive at two distinct families of analyses. The first is the well-known k-CFA family of analyses. The second consists of novel "environment-centric" abstract interpretations, none of which appear in the literature on static analysis of higher-order programs.

  19. Abstracts of SIG Sessions.

    ERIC Educational Resources Information Center

    Proceedings of the ASIS Annual Meeting, 1997

    1997-01-01

    Presents abstracts of SIG Sessions. Highlights include digital collections; information retrieval methods; public interest/fair use; classification and indexing; electronic publication; funding; globalization; information technology projects; interface design; networking in developing countries; metadata; multilingual databases; networked…

  20. Automatic Abstraction in Planning

    NASA Technical Reports Server (NTRS)

    Christensen, J.

    1991-01-01

    Traditionally, abstraction in planning has been accomplished by either state abstraction or operator abstraction, neither of which has been fully automatic. We present a new method, predicate relaxation, for automatically performing state abstraction. PABLO, a nonlinear hierarchical planner, implements predicate relaxation. Theoretical, as well as empirical results are presented which demonstrate the potential advantages of using predicate relaxation in planning. We also present a new definition of hierarchical operators that allows us to guarantee a limited form of completeness. This new definition is shown to be, in some ways, more flexible than previous definitions of hierarchical operators. Finally, a Classical Truth Criterion is presented that is proven to be sound and complete for a planning formalism that is general enough to include most classical planning formalisms that are based on the STRIPS assumption.

  1. 1971 Annual Conference Abstracts

    ERIC Educational Resources Information Center

    Journal of Engineering Education, 1971

    1971-01-01

    Included are 112 abstracts listed under headings such as: acoustics, continuing engineering studies, educational research and methods, engineering design, libraries, liberal studies, and materials. Other areas include agricultural, electrical, mechanical, mineral, and ocean engineering. (TS)

  2. 2016 ACPA MEETING ABSTRACTS.

    PubMed

    2016-07-01

    The peer-reviewed abstracts presented at the 73rd Annual Meeting of the ACPA are published as submitted by the authors. For financial conflict of interest disclosure, please visit http://meeting.acpa-cpf.org/disclosures.html. PMID:27447885

  3. Abstracts of contributed papers

    SciTech Connect

    Not Available

    1994-08-01

    This volume contains 571 abstracts of contributed papers to be presented during the Twelfth US National Congress of Applied Mechanics. Abstracts are arranged in the order in which they fall in the program -- the main sessions are listed chronologically in the Table of Contents. The Author Index is in alphabetical order and lists each paper number (matching the schedule in the Final Program) with its corresponding page number in the book.

  4. Metacognition and abstract reasoning.

    PubMed

    Markovits, Henry; Thompson, Valerie A; Brisson, Janie

    2015-05-01

    The nature of people's meta-representations of deductive reasoning is critical to understanding how people control their own reasoning processes. We conducted two studies to examine whether people have a metacognitive representation of abstract validity and whether familiarity alone acts as a separate metacognitive cue. In Study 1, participants were asked to make a series of (1) abstract conditional inferences, (2) concrete conditional inferences with premises having many potential alternative antecedents and thus specifically conducive to the production of responses consistent with conditional logic, or (3) concrete problems with premises having relatively few potential alternative antecedents. Participants gave confidence ratings after each inference. Results show that confidence ratings were positively correlated with logical performance on abstract problems and concrete problems with many potential alternatives, but not with concrete problems with content less conducive to normative responses. Confidence ratings were higher with few alternatives than for abstract content. Study 2 used a generation of contrary-to-fact alternatives task to improve levels of abstract logical performance. The resulting increase in logical performance was mirrored by increases in mean confidence ratings. Results provide evidence for a metacognitive representation based on logical validity, and show that familiarity acts as a separate metacognitive cue. PMID:25416026

  5. Thyra Abstract Interface Package

    2005-09-01

    Thrya primarily defines a set of abstract C++ class interfaces needed for the development of abstract numerical atgorithms (ANAs) such as iterative linear solvers, transient solvers all the way up to optimization. At the foundation of these interfaces are abstract C++ classes for vectors, vector spaces, linear operators and multi-vectors. Also included in the Thyra package is C++ code for creating concrete vector, vector space, linear operator, and multi-vector subclasses as well as other utilitiesmore » to aid in the development of ANAs. Currently, very general and efficient concrete subclass implementations exist for serial and SPMD in-core vectors and multi-vectors. Code also currently exists for testing objects and providing composite objects such as product vectors.« less

  6. Abstracting and indexing guide

    USGS Publications Warehouse

    U.S. Department of the Interior; Office of Water Resources Research

    1974-01-01

    These instructions have been prepared for those who abstract and index scientific and technical documents for the Water Resources Scientific Information Center (WRSIC). With the recent publication growth in all fields, information centers have undertaken the task of keeping the various scientific communities aware of current and past developments. An abstract with carefully selected index terms offers the user of WRSIC services a more rapid means for deciding whether a document is pertinent to his needs and professional interests, thus saving him the time necessary to scan the complete work. These means also provide WRSIC with a document representation or surrogate which is more easily stored and manipulated to produce various services. Authors are asked to accept the responsibility for preparing abstracts of their own papers to facilitate quick evaluation, announcement, and dissemination to the scientific community.

  7. Abstraction and art.

    PubMed Central

    Gortais, Bernard

    2003-01-01

    In a given social context, artistic creation comprises a set of processes, which relate to the activity of the artist and the activity of the spectator. Through these processes we see and understand that the world is vaster than it is said to be. Artistic processes are mediated experiences that open up the world. A successful work of art expresses a reality beyond actual reality: it suggests an unknown world using the means and the signs of the known world. Artistic practices incorporate the means of creation developed by science and technology and change forms as they change. Artists and the public follow different processes of abstraction at different levels, in the definition of the means of creation, of representation and of perception of a work of art. This paper examines how the processes of abstraction are used within the framework of the visual arts and abstract painting, which appeared during a period of growing importance for the processes of abstraction in science and technology, at the beginning of the twentieth century. The development of digital platforms and new man-machine interfaces allow multimedia creations. This is performed under the constraint of phases of multidisciplinary conceptualization using generic representation languages, which tend to abolish traditional frontiers between the arts: visual arts, drama, dance and music. PMID:12903659

  8. The SIDdatagrabber (Abstract)

    NASA Astrophysics Data System (ADS)

    Silvis, G.

    2015-12-01

    (Abstract only) The Stanford/SARA SuperSid project offers an opportunity for adding data to the AAVSO SID Monitoring project. You can now build a SID antenna and monitoring setup for about $150. And with the SIDdatagrabber application you can easily re-purpose the data collected for the AAVSO.

  9. Making the Abstract Concrete

    ERIC Educational Resources Information Center

    Potter, Lee Ann

    2005-01-01

    President Ronald Reagan nominated a woman to serve on the United States Supreme Court. He did so through a single-page form letter, completed in part by hand and in part by typewriter, announcing Sandra Day O'Connor as his nominee. While the document serves as evidence of a historic event, it is also a tangible illustration of abstract concepts…

  10. Learning Abstracts, 2001.

    ERIC Educational Resources Information Center

    Wilson, Cynthia, Ed.

    2001-01-01

    Volume 4 of the League for Innovation in the Community College's Learning Abstracts include the following: (1) "Touching Students in the Digital Age: The Move Toward Learner Relationship Management (LRM)," by Mark David Milliron, which offers an overview of an organizing concept to help community colleges navigate the intersection between digital…

  11. Leadership Abstracts, 2002.

    ERIC Educational Resources Information Center

    Wilson, Cynthia, Ed.; Milliron, Mark David, Ed.

    2002-01-01

    This 2002 volume of Leadership Abstracts contains issue numbers 1-12. Articles include: (1) "Skills Certification and Workforce Development: Partnering with Industry and Ourselves," by Jeffrey A. Cantor; (2) "Starting Again: The Brookhaven Success College," by Alice W. Villadsen; (3) "From Digital Divide to Digital Democracy," by Gerardo E. de los…

  12. Leadership Abstracts, 1993.

    ERIC Educational Resources Information Center

    Doucette, Don, Ed.

    1993-01-01

    This document includes 10 issues of Leadership Abstracts (volume 6, 1993), a newsletter published by the League for Innovation in the Community College (California). The featured articles are: (1) "Reinventing Government" by David T. Osborne; (2) "Community College Workforce Training Programs: Expanding the Mission to Meet Critical Needs" by…

  13. Abstraction through Game Play

    ERIC Educational Resources Information Center

    Avraamidou, Antri; Monaghan, John; Walker, Aisha

    2012-01-01

    This paper examines the computer game play of an 11-year-old boy. In the course of building a virtual house he developed and used, without assistance, an artefact and an accompanying strategy to ensure that his house was symmetric. We argue that the creation and use of this artefact-strategy is a mathematical abstraction. The discussion…

  14. CIRF Abstracts, Volume 12.

    ERIC Educational Resources Information Center

    International Labour Office, Geneva (Switzerland).

    The aim of the CIRF abstracts is to convey information about vocational training ideas, programs, experience, and experiments described in periodicals, books, and other publications and relating to operative personnel, supervisors, and technical and training staff in all sectors of economic activity. Information is also given on major trends in…

  15. Leadership Abstracts, 1999.

    ERIC Educational Resources Information Center

    Leadership Abstracts, 1999

    1999-01-01

    This document contains five Leadership Abstracts publications published February-December 1999. The article, "Teaching the Teachers: Meeting the National Teacher Preparation Challenge," authored by George R. Boggs and Sadie Bragg, examines the community college role and makes recommendations and a call to action for teacher education. "Chaos…

  16. Double Trouble (Abstract)

    NASA Astrophysics Data System (ADS)

    Simonsen, M.

    2015-12-01

    (Abstract only) Variable stars with close companions can be difficult to accurately measure and characterize. The companions can create misidentifications, which in turn can affect the perceived magnitudes, amplitudes, periods, and colors of the variable stars. We will show examples of these Double Trouble stars and the impact their close companions have had on our understanding of some of these variable stars.

  17. Send Me No Abstract.

    ERIC Educational Resources Information Center

    Levy, Steven

    1985-01-01

    Discusses Magazine Index's practice of assigning letter grades (sometimes inaccurate) to book, restaurant, and movie reviews, thus allowing patrons to get the point of the review from the index rather than the article itself, and argues that this situation is indicative of the larger problem of reliability of abstracts. (MBR)

  18. Annual Conference Abstracts

    ERIC Educational Resources Information Center

    Engineering Education, 1976

    1976-01-01

    Presents the abstracts of 158 papers presented at the American Society for Engineering Education's annual conference at Knoxville, Tennessee, June 14-17, 1976. Included are engineering topics covering education, aerospace, agriculture, biomedicine, chemistry, computers, electricity, acoustics, environment, mechanics, and women. (SL)

  19. Reasoning abstractly about resources

    NASA Technical Reports Server (NTRS)

    Clement, B.; Barrett, A.

    2001-01-01

    r describes a way to schedule high level activities before distributing them across multiple rovers in order to coordinate the resultant use of shared resources regardless of how each rover decides how to perform its activities. We present an algorithm for summarizing the metric resource requirements of an abstract activity based n the resource usages of its potential refinements.

  20. Humor, abstraction, and disbelief.

    PubMed

    Hoicka, Elena; Jutsum, Sarah; Gattis, Merideth

    2008-09-01

    We investigated humor as a context for learning about abstraction and disbelief. More specifically, we investigated how parents support humor understanding during book sharing with their toddlers. In Study 1, a corpus analysis revealed that in books aimed at 1-to 2-year-olds, humor is found more often than other forms of doing the wrong thing including mistakes, pretense, lying, false beliefs, and metaphors. In Study 2, 20 parents read a book containing humorous and non-humorous pages to their 19-to 26-month-olds. Parents used a significantly higher percentage of high abstraction extra-textual utterances (ETUs) when reading the humorous pages. In Study 3, 41 parents read either a humorous or non-humorous book to their 18-to 24-month-olds. Parents reading the humorous book made significantly more ETUs coded for a specific form of high abstraction: those encouraging disbelief of prior utterances. Sharing humorous books thus increases toddlers' exposure to high abstraction and belief-based language. PMID:21585438

  1. Abstracts of SIG Sessions.

    ERIC Educational Resources Information Center

    Proceedings of the ASIS Annual Meeting, 1995

    1995-01-01

    Presents abstracts of 15 special interest group (SIG) sessions. Topics include navigation and information utilization in the Internet, natural language processing, automatic indexing, image indexing, classification, users' models of database searching, online public access catalogs, education for information professions, information services,…

  2. 2002 NASPSA Conference Abstracts.

    ERIC Educational Resources Information Center

    Journal of Sport & Exercise Psychology, 2002

    2002-01-01

    Contains abstracts from the 2002 conference of the North American Society for the Psychology of Sport and Physical Activity. The publication is divided into three sections: the preconference workshop, "Effective Teaching Methods in the Classroom;" symposia (motor development, motor learning and control, and sport psychology); and free…

  3. Annual Conference Abstracts

    ERIC Educational Resources Information Center

    Journal of Engineering Education, 1972

    1972-01-01

    Includes abstracts of papers presented at the 80th Annual Conference of the American Society for Engineering Education. The broad areas include aerospace, affiliate and associate member council, agricultural engineering, biomedical engineering, continuing engineering studies, chemical engineering, civil engineering, computers, cooperative…

  4. Learning Abstracts, 1999.

    ERIC Educational Resources Information Center

    League for Innovation in the Community Coll.

    This document contains volume two of Learning Abstracts, a bimonthly newsletter from the League for Innovation in the Community College. Articles in these seven issues include: (1) "Get on the Fast Track to Learning: An Accelerated Associate Degree Option" (Gerardo E. de los Santos and Deborah J. Cruise); (2) "The Learning College: Both Learner…

  5. Computers in Abstract Algebra

    ERIC Educational Resources Information Center

    Nwabueze, Kenneth K.

    2004-01-01

    The current emphasis on flexible modes of mathematics delivery involving new information and communication technology (ICT) at the university level is perhaps a reaction to the recent change in the objectives of education. Abstract algebra seems to be one area of mathematics virtually crying out for computer instructional support because of the…

  6. Abstract Film and Beyond.

    ERIC Educational Resources Information Center

    Le Grice, Malcolm

    A theoretical and historical account of the main preoccupations of makers of abstract films is presented in this book. The book's scope includes discussion of nonrepresentational forms as well as examination of experiments in the manipulation of time in films. The ten chapters discuss the following topics: art and cinematography, the first…

  7. The Social Background of the Student and His Prospect of Success at School.

    ERIC Educational Resources Information Center

    Office of Education (DHEW), Washington, DC.

    This document is an English-language abstract (approximately 1,500 words) of the American response to an IBE questionnaire. The main problems in the relationship between social background and school achievement are how to ensure equality of educational opportunity in all 50 states, raising educational standards and improving the quality of schools…

  8. Approximate Genealogies Under Genetic Hitchhiking

    PubMed Central

    Pfaffelhuber, P.; Haubold, B.; Wakolbinger, A.

    2006-01-01

    The rapid fixation of an advantageous allele leads to a reduction in linked neutral variation around the target of selection. The genealogy at a neutral locus in such a selective sweep can be simulated by first generating a random path of the advantageous allele's frequency and then a structured coalescent in this background. Usually the frequency path is approximated by a logistic growth curve. We discuss an alternative method that approximates the genealogy by a random binary splitting tree, a so-called Yule tree that does not require first constructing a frequency path. Compared to the coalescent in a logistic background, this method gives a slightly better approximation for identity by descent during the selective phase and a much better approximation for the number of lineages that stem from the founder of the selective sweep. In applications such as the approximation of the distribution of Tajima's D, the two approximation methods perform equally well. For relevant parameter ranges, the Yule approximation is faster. PMID:17182733

  9. Historical development of abstracting.

    PubMed

    Skolnik, H

    1979-11-01

    The abstract, under a multitude of names, such as hypothesis, marginalia, abridgement, extract, digest, précis, resumé, and summary, has a long history, one which is concomitant with advancing scholarship. The progression of this history from the Sumerian civilization ca. 3600 B.C., through the Egyptian and Greek civilizations, the Hellenistic period, the Dark Ages, Middle Ages, Renaissance, and into the modern period is reviewed. PMID:399482

  10. Generalized Abstract Symbolic Summaries

    NASA Technical Reports Server (NTRS)

    Person, Suzette; Dwyer, Matthew B.

    2009-01-01

    Current techniques for validating and verifying program changes often consider the entire program, even for small changes, leading to enormous V&V costs over a program s lifetime. This is due, in large part, to the use of syntactic program techniques which are necessarily imprecise. Building on recent advances in symbolic execution of heap manipulating programs, in this paper, we develop techniques for performing abstract semantic differencing of program behaviors that offer the potential for improved precision.

  11. A LARI Experience (Abstract)

    NASA Astrophysics Data System (ADS)

    Cook, M.

    2015-12-01

    (Abstract only) In 2012, Lowell Observatory launched The Lowell Amateur Research Initiative (LARI) to formally involve amateur astronomers in scientific research by bringing them to the attention of and helping professional astronomers with their astronomical research. One of the LARI projects is the BVRI photometric monitoring of Young Stellar Objects (YSOs), wherein amateurs obtain observations to search for new outburst events and characterize the colour evolution of previously identified outbursters. A summary of the scientific and organizational aspects of this LARI project, including its goals and science motivation, the process for getting involved with the project, a description of the team members, their equipment and methods of collaboration, and an overview of the programme stars, preliminary findings, and lessons learned is presented.

  12. IEEE conference record -- Abstracts

    SciTech Connect

    Not Available

    1994-01-01

    This conference covers the following areas: computational plasma physics; vacuum electronic; basic phenomena in fully ionized plasmas; plasma, electron, and ion sources; environmental/energy issues in plasma science; space plasmas; plasma processing; ball lightning/spherical plasma configurations; plasma processing; fast wave devices; magnetic fusion; basic phenomena in partially ionized plasma; dense plasma focus; plasma diagnostics; basic phenomena in weakly ionized gases; fast opening switches; MHD; fast z-pinches and x-ray lasers; intense ion and electron beams; laser-produced plasmas; microwave plasma interactions; EM and ETH launchers; solid state plasmas and switches; intense beam microwaves; and plasmas for lighting. Separate abstracts were prepared for 416 papers in this conference.

  13. Teaching for Abstraction: A Model

    ERIC Educational Resources Information Center

    White, Paul; Mitchelmore, Michael C.

    2010-01-01

    This article outlines a theoretical model for teaching elementary mathematical concepts that we have developed over the past 10 years. We begin with general ideas about the abstraction process and differentiate between "abstract-general" and "abstract-apart" concepts. A 4-phase model of teaching, called Teaching for Abstraction, is then proposed…

  14. Stellar Presentations (Abstract)

    NASA Astrophysics Data System (ADS)

    Young, D.

    2015-12-01

    (Abstract only) The AAVSO is in the process of expanding its education, outreach and speakers bureau program. powerpoint presentations prepared for specific target audiences such as AAVSO members, educators, students, the general public, and Science Olympiad teams, coaches, event supervisors, and state directors will be available online for members to use. The presentations range from specific and general content relating to stellar evolution and variable stars to specific activities for a workshop environment. A presentation—even with a general topic—that works for high school students will not work for educators, Science Olympiad teams, or the general public. Each audience is unique and requires a different approach. The current environment necessitates presentations that are captivating for a younger generation that is embedded in a highly visual and sound-bite world of social media, twitter and U-Tube, and mobile devices. For educators, presentations and workshops for themselves and their students must support the Next Generation Science Standards (NGSS), the Common Core Content Standards, and the Science Technology, Engineering and Mathematics (STEM) initiative. Current best practices for developing relevant and engaging powerpoint presentations to deliver information to a variety of targeted audiences will be presented along with several examples.

  15. Approximate flavor symmetries

    SciTech Connect

    Rasin, A.

    1994-04-01

    We discuss the idea of approximate flavor symmetries. Relations between approximate flavor symmetries and natural flavor conservation and democracy models is explored. Implications for neutrino physics are also discussed.

  16. An approximate model for pulsar navigation simulation

    NASA Astrophysics Data System (ADS)

    Jovanovic, Ilija; Enright, John

    2016-02-01

    This paper presents an approximate model for the simulation of pulsar aided navigation systems. High fidelity simulations of these systems are computationally intensive and impractical for simulating periods of a day or more. Simulation of yearlong missions is done by abstracting navigation errors as periodic Gaussian noise injections. This paper presents an intermediary approximate model to simulate position errors for periods of several weeks, useful for building more accurate Gaussian error models. This is done by abstracting photon detection and binning, replacing it with a simple deterministic process. The approximate model enables faster computation of error injection models, allowing the error model to be inexpensively updated throughout a simulation. Testing of the approximate model revealed an optimistic performance prediction for non-millisecond pulsars with more accurate predictions for pulsars in the millisecond spectrum. This performance gap was attributed to noise which is not present in the approximate model but can be predicted and added to improve accuracy.

  17. Abstraction of Drift Seepage

    SciTech Connect

    J.T. Birkholzer

    2004-11-01

    This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package corrosion or radionuclide transport.

  18. Replace with abstract title

    NASA Astrophysics Data System (ADS)

    Park, Daesik; Kang, Seongjun; Kim, Huijung; Whang, Jungnam

    2004-03-01

    The interface property of perylene thin-film and OTS (octadecyltriclorosilane) monolayer, and its effects on the characteristics of perylene thin-film transistor D. S. Park, S. J. Kang, H. J. Kim, and C. N. Whang Institute of Physics and Applied Physics, Yonsei University, Seoul, KOREA We researched the perylene thin-film which is known for the characteristics of both P-type, and N-type. Perylene thin-film was deposited on SiO2 substrates with different deposition rate. Next, to study the interface effects of OTS (octadecyltriclorosilane) we inserted OTS monolayer between perylene thin-film and SiO2 substrates. And we compared grain size and crystallinity with AFM (Atomoic Force Microscopy) and XRD (X-Ray Diffraction), then we got dramatically increased crystallinity and reduced film roughness with OTS treatment. And we studied the interface with XPS (X-ray Photoelectron Spectroscopy) and FESEM (Field Effect Single Electron Spectroscopy). Then we fabricated OTS inserted perylene thin-film transistor with different deposition rate and mesured current-voltage characteristics. And we got increased saturation current and hole mobility over a hundred time with OTS treatment on SiO2, the saturation current was over 1/1000000 A and mobility was approximately 0.1cm^2/Vs.

  19. Ozone Conference II: Abstract Proceedings

    SciTech Connect

    1999-11-01

    Ozone Conference II: Pre- and Post-Harvest Applications Two Years After Gras, was held September 27-28, 1999 in Tulare, California. This conference, sponsored by EPRI's Agricultural Technology Alliance and Southern California Edison's AgTAC facility, was coordinated and organized by the on-site ATA-AgTAC Regional Center. Approximately 175 people attended the day-and-a-half conference at AgTAC. During the Conference twenty-two presentations were given on ozone food processing and agricultural applications. Included in the presentations were topics on: (1) Ozone fumigation; (2) Ozone generation techniques; (3) System and design applications; (4) Prewater treatment requirements; (5) Poultry water reuse; (6) Soil treatments with ozone gas; and (7) Post-harvest aqueous and gaseous ozone research results. A live videoconference between Tulare and Washington, D.C. was held to discuss the regulators' view from inside the beltway. Attendees participated in two Roundtable Question and Answer sessions and visited fifteen exhibits and demonstrations. The attendees included university and governmental researchers, regulators, consultants and industry experts, technology developers and providers, and corporate and individual end-users. This report is comprised of the Abstracts of each presentation, biographical sketches for each speaker and a registration/attendees list.

  20. Astronomy posters. Abstracts.

    NASA Astrophysics Data System (ADS)

    van Woerden, H.

    Contents: IAU Symposia Nos. 164: Stellar populations. 165: Compact stars in binaries. 166: Astronomical and astrophysical objectives of sub-milliarcsecond optical astrometry. 167: New developments in array technology and applications. 168: Examining the Big Bang and diffuse background radiations. 169: Unsolved problems of the Milky Way. Joint Discussions Nos. 1: Gas disks in galaxies. 2: Origin and detection of planetary systems. 3: Helio- and asteroseismology. 4: Current developments in astronomy education. 5: Activity in the central parts of galaxies. 6: Sun and heliosphere - challenges for solar-terrestrial physics, magneto- and hydrodynamics. 7: History of astronomy. 8: Time scales - state of the art. 9: Women in astronomy. 10: Extragalactic planetary nebulae. 11: Stellar and interstellar lithium and primordial nucleosynthesis. 12: Accuracy of the HR diagram and related parameters. 13: Recent advances in convection theory and modelling. 14: Towards the establishment of the astronomical standards. 15: Statistical evaluation of astronomical time series. 16: Astrophysical applications of powerful new atomic databases. 17: Dust around young stars: How related to solar system dust? 18: Solar system radar observations. 19: Nutation. 20: The status of archiving astronomical data. Working Groups Nos. 1: Problems of astronomy in Africa. 2: Near-Earth objects detection. 3: International catalog projects. 4: Asteroids and comets.

  1. Advance Organizers: Concret Versus Abstract.

    ERIC Educational Resources Information Center

    Corkill, Alice J.; And Others

    1988-01-01

    Two experiments examined the relative effects of concrete and abstract advance organizers on students' memory for subsequent prose. Results of the experiments are discussed in terms of the memorability, familiarity, and visualizability of concrete and abstract verbal materials. (JD)

  2. Accepted scientific research works (abstracts).

    PubMed

    2014-01-01

    These are the 39 accepted abstracts for IAYT's Symposium on Yoga Research (SYR) September 24-24, 2014 at the Kripalu Center for Yoga & Health and published in the Final Program Guide and Abstracts. PMID:25645134

  3. Southern Orthopaedic Association Abstract Publication Rate.

    PubMed

    Tait, Mark Adam; Petrus, Cara; Barnes, C Lowry

    2016-01-01

    The purpose of this study was to determine the publication rate of manuscripts presented at the Southern Orthopaedic Association's (SOA) annual meetings. An extensive literature search was performed using Google Scholar and PubMed search engines and all accepted abstracts (posters or podium presentations) presented at an SOA annual meeting from 2005 to 2011 were evaluated. A total of 568 abstracts were presented at SOA meetings between 2005 and 2011. Of these, 234 (41%) were published in the peer-reviewed literature. The publication rate was 66% in 2005 and 28% in 2010. The average time from presentation to peer-reviewed publication was 1.6 ± 0.24 years (range, 2 years in 2006 to 1 year in 2011). The SOA publication rate was comparable with other major orthopaedic conference publication rates, yet more than half of all abstracts remain unpublished. SOA attendees should be aware that approximately 40% of all accepted presentations will go unpublished. PMID:27518291

  4. Attracting Girls into Physics (abstract)

    NASA Astrophysics Data System (ADS)

    Gadalla, Afaf

    2009-04-01

    A recent international study of women in physics showed that enrollment in physics and science is declining for both males and females and that women are severely underrepresented in careers requiring a strong physics background. The gender gap begins early in the pipeline, from the first grade. Girls are treated differently than boys at home and in society in ways that often hinder their chances for success. They have fewer freedoms, are discouraged from accessing resources or being adventurous, have far less exposure to problem solving, and are not encouraged to choose their lives. In order to motivate more girl students to study physics in the Assiut governorate of Egypt, the Assiut Alliance for the Women and Assiut Education District collaborated in renovating the education of physics in middle and secondary school classrooms. A program that helps in increasing the number of girls in science and physics has been designed in which informal groupings are organized at middle and secondary schools to involve girls in the training and experiences needed to attract and encourage girls to learn physics. During implementation of the program at some schools, girls, because they had not been trained in problem-solving as boys, appeared not to be as facile in abstracting the ideas of physics, and that was the primary reason for girls dropping out of science and physics. This could be overcome by holding a topical physics and technology summer school under the supervision of the Assiut Alliance for the Women.

  5. Hydrogen energy: A bibliography with abstracts. Cumulative volume, 1953 - 1973

    NASA Technical Reports Server (NTRS)

    Cox, K. E.

    1974-01-01

    A bibliography on hydrogen as an energy source is presented. Approximately 8,000 documents are abstracted covering the period 1953 through 1973. Topics covered include: production, utilization, transmission, distribution, storage, and safety.

  6. Approximate spatial reasoning

    NASA Technical Reports Server (NTRS)

    Dutta, Soumitra

    1988-01-01

    A model for approximate spatial reasoning using fuzzy logic to represent the uncertainty in the environment is presented. Algorithms are developed which can be used to reason about spatial information expressed in the form of approximate linguistic descriptions similar to the kind of spatial information processed by humans. Particular attention is given to static spatial reasoning.

  7. Mechanical Engineering Department technical abstracts

    SciTech Connect

    Denney, R.M.

    1982-07-01

    The Mechanical Engineering Department publishes listings of technical abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). Overall information about current activities of each of the Department's seven divisions precedes the technical abstracts.

  8. Recursive Abstractions for Parameterized Systems

    NASA Astrophysics Data System (ADS)

    Jaffar, Joxan; Santosa, Andrew E.

    We consider a language of recursively defined formulas about arrays of variables, suitable for specifying safety properties of parameterized systems. We then present an abstract interpretation framework which translates a paramerized system as a symbolic transition system which propagates such formulas as abstractions of underlying concrete states. The main contribution is a proof method for implications between the formulas, which then provides for an implementation of this abstract interpreter.

  9. Calculator Function Approximation.

    ERIC Educational Resources Information Center

    Schelin, Charles W.

    1983-01-01

    The general algorithm used in most hand calculators to approximate elementary functions is discussed. Comments on tabular function values and on computer function evaluation are given first; then the CORDIC (Coordinate Rotation Digital Computer) scheme is described. (MNS)

  10. The structural physical approximation conjecture

    NASA Astrophysics Data System (ADS)

    Shultz, Fred

    2016-01-01

    It was conjectured that the structural physical approximation (SPA) of an optimal entanglement witness is separable (or equivalently, that the SPA of an optimal positive map is entanglement breaking). This conjecture was disproved, first for indecomposable maps and more recently for decomposable maps. The arguments in both cases are sketched along with important related results. This review includes background material on topics including entanglement witnesses, optimality, duality of cones, decomposability, and the statement and motivation for the SPA conjecture so that it should be accessible for a broad audience.

  11. Approximate spatial reasoning

    NASA Technical Reports Server (NTRS)

    Dutta, Soumitra

    1988-01-01

    Much of human reasoning is approximate in nature. Formal models of reasoning traditionally try to be precise and reject the fuzziness of concepts in natural use and replace them with non-fuzzy scientific explicata by a process of precisiation. As an alternate to this approach, it has been suggested that rather than regard human reasoning processes as themselves approximating to some more refined and exact logical process that can be carried out with mathematical precision, the essence and power of human reasoning is in its capability to grasp and use inexact concepts directly. This view is supported by the widespread fuzziness of simple everyday terms (e.g., near tall) and the complexity of ordinary tasks (e.g., cleaning a room). Spatial reasoning is an area where humans consistently reason approximately with demonstrably good results. Consider the case of crossing a traffic intersection. We have only an approximate idea of the locations and speeds of various obstacles (e.g., persons and vehicles), but we nevertheless manage to cross such traffic intersections without any harm. The details of our mental processes which enable us to carry out such intricate tasks in such apparently simple manner are not well understood. However, it is that we try to incorporate such approximate reasoning techniques in our computer systems. Approximate spatial reasoning is very important for intelligent mobile agents (e.g., robots), specially for those operating in uncertain or unknown or dynamic domains.

  12. Approximate kernel competitive learning.

    PubMed

    Wu, Jian-Sheng; Zheng, Wei-Shi; Lai, Jian-Huang

    2015-03-01

    Kernel competitive learning has been successfully used to achieve robust clustering. However, kernel competitive learning (KCL) is not scalable for large scale data processing, because (1) it has to calculate and store the full kernel matrix that is too large to be calculated and kept in the memory and (2) it cannot be computed in parallel. In this paper we develop a framework of approximate kernel competitive learning for processing large scale dataset. The proposed framework consists of two parts. First, it derives an approximate kernel competitive learning (AKCL), which learns kernel competitive learning in a subspace via sampling. We provide solid theoretical analysis on why the proposed approximation modelling would work for kernel competitive learning, and furthermore, we show that the computational complexity of AKCL is largely reduced. Second, we propose a pseudo-parallelled approximate kernel competitive learning (PAKCL) based on a set-based kernel competitive learning strategy, which overcomes the obstacle of using parallel programming in kernel competitive learning and significantly accelerates the approximate kernel competitive learning for large scale clustering. The empirical evaluation on publicly available datasets shows that the proposed AKCL and PAKCL can perform comparably as KCL, with a large reduction on computational cost. Also, the proposed methods achieve more effective clustering performance in terms of clustering precision against related approximate clustering approaches. PMID:25528318

  13. Concrete and Abstract Visualizations in History Learning Tasks

    ERIC Educational Resources Information Center

    Prangsma, Maaike E.; van Boxtel, Carla A. M.; Kanselaar, Gellof; Kirschner, Paul A.

    2009-01-01

    Background: History learning requires that students understand historical phenomena, abstract concepts and the relations between them. Students have problems grasping, using and relating complex historical developments and structures. Aims: A study was conducted to determine the effects of tasks with abstract and/or concrete visualizations on the…

  14. Abstracts

    NASA Astrophysics Data System (ADS)

    2012-09-01

    Measuring cosmological parameters with GRBs: status and perspectives New interpretation of the Amati relation The SED Machine - a dedicated transient spectrograph PTF10iue - evidence for an internal engine in a unique Type Ic SN Direct evidence for the collapsar model of long gamma-ray bursts On pair instability supernovae and gamma-ray bursts Pan-STARRS1 observations of ultraluminous SNe The influence of rotation on the critical neutrino luminosity in core-collapse supernovae General relativistic magnetospheres of slowly rotating and oscillating neutron stars Host galaxies of short GRBs GRB 100418A: a bridge between GRB-associated hypernovae and SNe Two super-luminous SNe at z ~ 1.5 from the SNLS Prospects for very-high-energy gamma-ray bursts with the Cherenkov Telescope Array The dynamics and radiation of relativistic flows from massive stars The search for light echoes from the supernova explosion of 1181 AD The proto-magnetar model for gamma-ray bursts Stellar black holes at the dawn of the universe MAXI J0158-744: the discovery of a supersoft X-ray transient Wide-band spectra of magnetar burst emission Dust formation and evolution in envelope-stripped core-collapse supernovae The host galaxies of dark gamma-ray bursts Keck observations of 150 GRB host galaxies Search for properties of GRBs at large redshift The early emission from SNe Spectral properties of SN shock breakout MAXI observation of GRBs and short X-ray transients A three-dimensional view of SN 1987A using light echo spectroscopy X-ray study of the southern extension of the SNR Puppis A All-sky survey of short X-ray transients by MAXI GSC Development of the CALET gamma-ray burst monitor (CGBM)

  15. Vague Language in Conference Abstracts

    ERIC Educational Resources Information Center

    Cutting, Joan

    2012-01-01

    This study examined abstracts for a British Association for Applied Linguistics conference and a Sociolinguistics Symposium, to define the genre of conference abstracts in terms of vague language, specifically universal general nouns (e.g. people) and research general nouns (e.g. results), and to discover if the language used reflected the level…

  16. Leadership Abstracts; Volume 4, 1991.

    ERIC Educational Resources Information Center

    Doucette, Don, Ed.

    1991-01-01

    "Leadership Abstracts" is published bimonthly and distributed to the chief executive officer of every two-year college in the United States and Canada. This document consists of the 15 one-page abstracts published in 1991. Addressing a variety of topics of interest to the community college administrators, this volume includes: (1) "Delivering the…

  17. Food Science and Technology Abstracts.

    ERIC Educational Resources Information Center

    Cohen, Elinor; Federman, Joan

    1979-01-01

    Introduces the reader to the Food Science and Technology Abstracts, a data file that covers worldwide literature on human food commodities and aspects of food processing. Topics include scope, subject index, thesaurus, searching online, and abstracts; tables provide a comparison of ORBIT and DIALOG versions of the file. (JD)

  18. Innovation Abstracts, Volume XV, 1993.

    ERIC Educational Resources Information Center

    Roueche, Suanne D., Ed.

    1993-01-01

    This volume of 30 one- to two-page abstracts from 1993 highlights a variety of innovative approaches to teaching and learning in the community college. Topics covered in the abstracts include: (1) role-playing to encourage critical thinking; (2) team learning techniques to cultivate business skills; (3) librarian-instructor partnerships to create…

  19. Student Success with Abstract Art

    ERIC Educational Resources Information Center

    Hamidou, Kristine

    2009-01-01

    An abstract art project can be challenging or not, depending on the objectives the teacher sets up. In this article, the author describes an abstract papier-mache project that is a success for all students, and is a versatile project easily manipulated to suit the classroom of any art teacher.

  20. Technical abstracts: Mechanical engineering, 1990

    SciTech Connect

    Broesius, J.Y.

    1991-03-01

    This document is a compilation of the published, unclassified abstracts produced by mechanical engineers at Lawrence Livermore National Laboratory (LLNL) during the calendar year 1990. Many abstracts summarize work completed and published in report form. These are UCRL-JC series documents, which include the full text of articles to be published in journals and of papers to be presented at meetings, and UCID reports, which are informal documents. Not all UCIDs contain abstracts: short summaries were generated when abstracts were not included. Technical Abstracts also provides descriptions of those documents assigned to the UCRL-MI (miscellaneous) category. These are generally viewgraphs or photographs presented at meetings. An author index is provided at the back of this volume for cross referencing.

  1. Metaphor: Bridging embodiment to abstraction.

    PubMed

    Jamrozik, Anja; McQuire, Marguerite; Cardillo, Eileen R; Chatterjee, Anjan

    2016-08-01

    Embodied cognition accounts posit that concepts are grounded in our sensory and motor systems. An important challenge for these accounts is explaining how abstract concepts, which do not directly call upon sensory or motor information, can be informed by experience. We propose that metaphor is one important vehicle guiding the development and use of abstract concepts. Metaphors allow us to draw on concrete, familiar domains to acquire and reason about abstract concepts. Additionally, repeated metaphoric use drawing on particular aspects of concrete experience can result in the development of new abstract representations. These abstractions, which are derived from embodied experience but lack much of the sensorimotor information associated with it, can then be flexibly applied to understand new situations. PMID:27294425

  2. Generative electronic background music system

    SciTech Connect

    Mazurowski, Lukasz

    2015-03-10

    In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions.

  3. Covariant approximation averaging

    NASA Astrophysics Data System (ADS)

    Shintani, Eigo; Arthur, Rudy; Blum, Thomas; Izubuchi, Taku; Jung, Chulwoo; Lehner, Christoph

    2015-06-01

    We present a new class of statistical error reduction techniques for Monte Carlo simulations. Using covariant symmetries, we show that correlation functions can be constructed from inexpensive approximations without introducing any systematic bias in the final result. We introduce a new class of covariant approximation averaging techniques, known as all-mode averaging (AMA), in which the approximation takes account of contributions of all eigenmodes through the inverse of the Dirac operator computed from the conjugate gradient method with a relaxed stopping condition. In this paper we compare the performance and computational cost of our new method with traditional methods using correlation functions and masses of the pion, nucleon, and vector meson in Nf=2 +1 lattice QCD using domain-wall fermions. This comparison indicates that AMA significantly reduces statistical errors in Monte Carlo calculations over conventional methods for the same cost.

  4. Fast approximate motif statistics.

    PubMed

    Nicodème, P

    2001-01-01

    We present in this article a fast approximate method for computing the statistics of a number of non-self-overlapping matches of motifs in a random text in the nonuniform Bernoulli model. This method is well suited for protein motifs where the probability of self-overlap of motifs is small. For 96% of the PROSITE motifs, the expectations of occurrences of the motifs in a 7-million-amino-acids random database are computed by the approximate method with less than 1% error when compared with the exact method. Processing of the whole PROSITE takes about 30 seconds with the approximate method. We apply this new method to a comparison of the C. elegans and S. cerevisiae proteomes. PMID:11535175

  5. The Guiding Center Approximation

    NASA Astrophysics Data System (ADS)

    Pedersen, Thomas Sunn

    The guiding center approximation for charged particles in strong magnetic fields is introduced here. This approximation is very useful in situations where the charged particles are very well magnetized, such that the gyration (Larmor) radius is small compared to relevant length scales of the confinement device, and the gyration is fast relative to relevant timescales in an experiment. The basics of motion in a straight, uniform, static magnetic field are reviewed, and are used as a starting point for analyzing more complicated situations where more forces are present, as well as inhomogeneities in the magnetic field -- magnetic curvature as well as gradients in the magnetic field strength. The first and second adiabatic invariant are introduced, and slowly time-varying fields are also covered. As an example of the use of the guiding center approximation, the confinement concept of the cylindrical magnetic mirror is analyzed.

  6. Monotone Boolean approximation

    SciTech Connect

    Hulme, B.L.

    1982-12-01

    This report presents a theory of approximation of arbitrary Boolean functions by simpler, monotone functions. Monotone increasing functions can be expressed without the use of complements. Nonconstant monotone increasing functions are important in their own right since they model a special class of systems known as coherent systems. It is shown here that when Boolean expressions for noncoherent systems become too large to treat exactly, then monotone approximations are easily defined. The algorithms proposed here not only provide simpler formulas but also produce best possible upper and lower monotone bounds for any Boolean function. This theory has practical application for the analysis of noncoherent fault trees and event tree sequences.

  7. NASA Patent Abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 21) Abstracts

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Abstracts are cited for 87 patents and applications introduced into the NASA scientific and technical information system during the period of January 1982 through June 1982. Each entry consists of a citation, an abstract, and in mose cases, a key illustration selected from the patent or patent application.

  8. Approximating Integrals Using Probability

    ERIC Educational Resources Information Center

    Maruszewski, Richard F., Jr.; Caudle, Kyle A.

    2005-01-01

    As part of a discussion on Monte Carlo methods, which outlines how to use probability expectations to approximate the value of a definite integral. The purpose of this paper is to elaborate on this technique and then to show several examples using visual basic as a programming tool. It is an interesting method because it combines two branches of…

  9. Multicriteria approximation through decomposition

    SciTech Connect

    Burch, C. |; Krumke, S.; Marathe, M.; Phillips, C.; Sundberg, E. |

    1997-12-01

    The authors propose a general technique called solution decomposition to devise approximation algorithms with provable performance guarantees. The technique is applicable to a large class of combinatorial optimization problems that can be formulated as integer linear programs. Two key ingredients of the technique involve finding a decomposition of a fractional solution into a convex combination of feasible integral solutions and devising generic approximation algorithms based on calls to such decompositions as oracles. The technique is closely related to randomized rounding. The method yields as corollaries unified solutions to a number of well studied problems and it provides the first approximation algorithms with provable guarantees for a number of new problems. The particular results obtained in this paper include the following: (1) The authors demonstrate how the technique can be used to provide more understanding of previous results and new algorithms for classical problems such as Multicriteria Spanning Trees, and Suitcase Packing. (2) They show how the ideas can be extended to apply to multicriteria optimization problems, in which they wish to minimize a certain objective function subject to one or more budget constraints. As corollaries they obtain first non-trivial multicriteria approximation algorithms for problems including the k-Hurdle and the Network Inhibition problems.

  10. Multicriteria approximation through decomposition

    SciTech Connect

    Burch, C.; Krumke, S.; Marathe, M.; Phillips, C.; Sundberg, E.

    1998-06-01

    The authors propose a general technique called solution decomposition to devise approximation algorithms with provable performance guarantees. The technique is applicable to a large class of combinatorial optimization problems that can be formulated as integer linear programs. Two key ingredients of their technique involve finding a decomposition of a fractional solution into a convex combination of feasible integral solutions and devising generic approximation algorithms based on calls to such decompositions as oracles. The technique is closely related to randomized rounding. Their method yields as corollaries unified solutions to a number of well studied problems and it provides the first approximation algorithms with provable guarantees for a number of new problems. The particular results obtained in this paper include the following: (1) the authors demonstrate how the technique can be used to provide more understanding of previous results and new algorithms for classical problems such as Multicriteria Spanning Trees, and Suitcase Packing; (2) they also show how the ideas can be extended to apply to multicriteria optimization problems, in which they wish to minimize a certain objective function subject to one or more budget constraints. As corollaries they obtain first non-trivial multicriteria approximation algorithms for problems including the k-Hurdle and the Network Inhibition problems.

  11. Genetical background of intelligence.

    PubMed

    Junkiert-Czarnecka, Anna; Haus, Olga

    2016-01-01

    Intelligence as an ability to reason, think abstractly and adapt effectively to the environment is a subject of research in the field of psychology, neurobiology, and in the last twenty years genetics as well. Genetical testing of twins carried out from XX century indicated heritebility of intelligence, therefore confirmed an influence of genetic factor on cognitive processes. Studies on genetic background of intelligence focus on dopaminergic (DRD2, DRD4, COMT, SLC6A3, DAT1, CCKAR) and adrenergic system (ADRB2, CHRM2) genes as well as, neutrofins (BDNF) and oxidative stress genes (LTF, PRNP). Positive effect of investigated gene polymorphism was indicated by variation c.957C>T DRD2 gene (if in polymorphic site is thymine), polymorphism c.472G>A COMT gene (presence of adenine) and also gene ADRB2 c.46A->G (guanine), CHRM2 (thymine in place c.1890A>T) and BDNF (guanine in place c.472G>A) Obtained results indicate that intelligence is a feature dependent not only on genetic but also an environmental factor. PMID:27333929

  12. Teaching Abstract Concepts by Metaphor.

    ERIC Educational Resources Information Center

    Sutherland, Judith A.

    2001-01-01

    Defines metaphor and its uses; explains the construction and application of metaphors in nursing education. Describes the transformation of the abstract psychiatric concept of therapeutic milieu into a visual metaphor. (SK)

  13. Deficiencies in structured medical abstracts.

    PubMed

    Froom, P; Froom, J

    1993-07-01

    This study was carried out to determine if the content of structured abstracts conforms with recommendations of the Ad Hoc Working Group for the critical appraisal of the medical literature as adopted by the Annals of Internal Medicine. The study design was a survey. All articles published in Annals of Internal Medicine in 1991, excluding editorials, case-reports, literature reviews, decision analysis, studies in medical education, descriptive studies of clinical and basic phenomena, and papers lacking a structured abstract, were studied. Of a total of 150 articles, 20 were excluded. The abstract and text of each article were assessed for the presence of the following items; patient selection criteria, statements concerning extrapolation of findings, need for further study, and whether or not the information should be used now. Number of refusers, drop outs and reason(s) for drop outs were assessed for intervention and prospective cohort studies only. Deficiencies of assessed items were noted in both abstracts and texts. For abstracts, patient selection criteria, numbers of refusers, number of drop outs and reason(s) for drop outs were reported in 44.6% (58/130), 3.1% (4/130), 16.9% (14/83) and 2.4% (2/83) respectively. These items were reported more frequently in the texts 87.7% (114/130), 9.2% (12/130), 60.2% (50/83) and 37.3% (31/83) respectively (p < 0.05). Statements concerning extrapolation of findings, need for further study and use of information now were also more frequent in texts than abstracts (p < 0.0001). A large number of structured abstracts published in the Annals of Internal Medicine in 1991, lack information recommended by the Ad Hoc Working Group. Our findings should not be extrapolated to other journals requiring structured abstracts. PMID:8326342

  14. Optimizing the Zeldovich approximation

    NASA Technical Reports Server (NTRS)

    Melott, Adrian L.; Pellman, Todd F.; Shandarin, Sergei F.

    1994-01-01

    We have recently learned that the Zeldovich approximation can be successfully used for a far wider range of gravitational instability scenarios than formerly proposed; we study here how to extend this range. In previous work (Coles, Melott and Shandarin 1993, hereafter CMS) we studied the accuracy of several analytic approximations to gravitational clustering in the mildly nonlinear regime. We found that what we called the 'truncated Zeldovich approximation' (TZA) was better than any other (except in one case the ordinary Zeldovich approximation) over a wide range from linear to mildly nonlinear (sigma approximately 3) regimes. TZA was specified by setting Fourier amplitudes equal to zero for all wavenumbers greater than k(sub nl), where k(sub nl) marks the transition to the nonlinear regime. Here, we study the cross correlation of generalized TZA with a group of n-body simulations for three shapes of window function: sharp k-truncation (as in CMS), a tophat in coordinate space, or a Gaussian. We also study the variation in the crosscorrelation as a function of initial truncation scale within each type. We find that k-truncation, which was so much better than other things tried in CMS, is the worst of these three window shapes. We find that a Gaussian window e(exp(-k(exp 2)/2k(exp 2, sub G))) applied to the initial Fourier amplitudes is the best choice. It produces a greatly improved crosscorrelation in those cases which most needed improvement, e.g. those with more small-scale power in the initial conditions. The optimum choice of kG for the Gaussian window is (a somewhat spectrum-dependent) 1 to 1.5 times k(sub nl). Although all three windows produce similar power spectra and density distribution functions after application of the Zeldovich approximation, the agreement of the phases of the Fourier components with the n-body simulation is better for the Gaussian window. We therefore ascribe the success of the best-choice Gaussian window to its superior treatment

  15. Approximate option pricing

    SciTech Connect

    Chalasani, P.; Saias, I.; Jha, S.

    1996-04-08

    As increasingly large volumes of sophisticated options (called derivative securities) are traded in world financial markets, determining a fair price for these options has become an important and difficult computational problem. Many valuation codes use the binomial pricing model, in which the stock price is driven by a random walk. In this model, the value of an n-period option on a stock is the expected time-discounted value of the future cash flow on an n-period stock price path. Path-dependent options are particularly difficult to value since the future cash flow depends on the entire stock price path rather than on just the final stock price. Currently such options are approximately priced by Monte carlo methods with error bounds that hold only with high probability and which are reduced by increasing the number of simulation runs. In this paper the authors show that pricing an arbitrary path-dependent option is {number_sign}-P hard. They show that certain types f path-dependent options can be valued exactly in polynomial time. Asian options are path-dependent options that are particularly hard to price, and for these they design deterministic polynomial-time approximate algorithms. They show that the value of a perpetual American put option (which can be computed in constant time) is in many cases a good approximation to the value of an otherwise identical n-period American put option. In contrast to Monte Carlo methods, the algorithms have guaranteed error bounds that are polynormally small (and in some cases exponentially small) in the maturity n. For the error analysis they derive large-deviation results for random walks that may be of independent interest.

  16. Beyond the Kirchhoff approximation

    NASA Technical Reports Server (NTRS)

    Rodriguez, Ernesto

    1989-01-01

    The three most successful models for describing scattering from random rough surfaces are the Kirchhoff approximation (KA), the small-perturbation method (SPM), and the two-scale-roughness (or composite roughness) surface-scattering (TSR) models. In this paper it is shown how these three models can be derived rigorously from one perturbation expansion based on the extinction theorem for scalar waves scattering from perfectly rigid surface. It is also shown how corrections to the KA proportional to the surface curvature and higher-order derivatives may be obtained. Using these results, the scattering cross section is derived for various surface models.

  17. Modelling Metamorphism by Abstract Interpretation

    NASA Astrophysics Data System (ADS)

    Dalla Preda, Mila; Giacobazzi, Roberto; Debray, Saumya; Coogan, Kevin; Townsend, Gregg M.

    Metamorphic malware apply semantics-preserving transformations to their own code in order to foil detection systems based on signature matching. In this paper we consider the problem of automatically extract metamorphic signatures from these malware. We introduce a semantics for self-modifying code, later called phase semantics, and prove its correctness by showing that it is an abstract interpretation of the standard trace semantics. Phase semantics precisely models the metamorphic code behavior by providing a set of traces of programs which correspond to the possible evolutions of the metamorphic code during execution. We show that metamorphic signatures can be automatically extracted by abstract interpretation of the phase semantics, and that regular metamorphism can be modelled as finite state automata abstraction of the phase semantics.

  18. Mechanical Engineering Department technical abstracts

    SciTech Connect

    Not Available

    1984-07-01

    The Mechanical Engineering Department publishes abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). General information about the current role and activities of each of the Department's seven divisions precedes the technical abstracts. Further information about a division's work may be obtained from the division leader, whose name is given at the end of each divisional summary. The Department's seven divisions are as follows: Nuclear Test Engineering Division, Nuclear Explosives Engineering Division, Weapons Engineering Division, Energy Systems Engineering Division, Engineering Sciences Division, Magnetic Fusion Engineering Division and Materials Fabrication Division.

  19. Meeting Abstracts - Annual Meeting 2016.

    PubMed

    2016-04-01

    The AMCP Abstracts program provides a forum through which authors can share their insights and outcomes of advanced managed care practice through publication in AMCP's Journal of Managed Care & Specialty Pharmacy (JMCP). Most of the reviewed and unreviewed abstracts are presented as posters so that interested AMCP meeting attendees can review findings and query authors. The Student/Resident/ Fellow poster presentation (unreviewed) is Wednesday, April 20, 2016, and the Professional poster presentation (reviewed) is Thursday, April 21. The Professional posters will also be displayed on Friday, April 22. The reviewed abstracts are published in the JMCP Meeting Abstracts supplement. The AMCP Managed Care & Specialty Pharmacy Annual Meeting 2016 in San Francisco, California, is expected to attract more than 3,500 managed care pharmacists and other health care professionals who manage and evaluate drug therapies, develop and manage networks, and work with medical managers and information specialists to improve the care of all individuals enrolled in managed care programs. Abstracts were submitted in the following categories: Research Report: describe completed original research on managed care pharmacy services or health care interventions. Examples include (but are not limited to) observational studies using administrative claims, reports of the impact of unique benefit design strategies, and analyses of the effects of innovative administrative or clinical programs. Economic Model: describe models that predict the effect of various benefit design or clinical decisions on a population. For example, an economic model could be used to predict the budget impact of a new pharmaceutical product on a health care system. Solving Problems in Managed Care: describe the specific steps taken to introduce a needed change, develop and implement a new system or program, plan and organize an administrative function, or solve other types of problems in managed care settings. These

  20. Abstract communication for coordinated planning

    NASA Technical Reports Server (NTRS)

    Clement, Bradley J.; Durfee, Edmund H.

    2003-01-01

    work offers evidence that distributed planning agents can greatly reduce communication costs by reasoning at abstract levels. While it is intuitive that improved search can reduce communication in such cases, there are other decisions about how to communicate plan information that greatly affect communication costs. This paper identifies cases independent of search where communicating at multiple levels of abstraction can exponentially decrease costs and where it can exponentially add costs. We conclude with a process for determining appropriate levels of communication based on characteristics of the domain.

  1. SATURATED ZONE FLOW AND TRANSPORT MODEL ABSTRACTION

    SciTech Connect

    B.W. ARNOLD

    2004-10-27

    The purpose of the saturated zone (SZ) flow and transport model abstraction task is to provide radionuclide-transport simulation results for use in the total system performance assessment (TSPA) for license application (LA) calculations. This task includes assessment of uncertainty in parameters that pertain to both groundwater flow and radionuclide transport in the models used for this purpose. This model report documents the following: (1) The SZ transport abstraction model, which consists of a set of radionuclide breakthrough curves at the accessible environment for use in the TSPA-LA simulations of radionuclide releases into the biosphere. These radionuclide breakthrough curves contain information on radionuclide-transport times through the SZ. (2) The SZ one-dimensional (I-D) transport model, which is incorporated in the TSPA-LA model to simulate the transport, decay, and ingrowth of radionuclide decay chains in the SZ. (3) The analysis of uncertainty in groundwater-flow and radionuclide-transport input parameters for the SZ transport abstraction model and the SZ 1-D transport model. (4) The analysis of the background concentration of alpha-emitting species in the groundwater of the SZ.

  2. Innovation Abstracts, Volume XIX, 1997.

    ERIC Educational Resources Information Center

    Roueche, Suanne D., Ed.

    1997-01-01

    The 52 abstracts in these 29 serial issues describe innovative approaches to teaching and learning in the community college. Sample topics include a checklist for conference presenters, plan to retain students, faculty home page, improvements in writing instruction, cooperative learning, support for high risk students, competitive colleges and the…

  3. Handedness Shapes Children's Abstract Concepts

    ERIC Educational Resources Information Center

    Casasanto, Daniel; Henetz, Tania

    2012-01-01

    Can children's handedness influence how they represent abstract concepts like "kindness" and "intelligence"? Here we show that from an early age, right-handers associate rightward space more strongly with positive ideas and leftward space with negative ideas, but the opposite is true for left-handers. In one experiment, children indicated where on…

  4. Innovation Abstracts, Volume XX, 1998.

    ERIC Educational Resources Information Center

    Roueche, Suanne D., Ed.

    1998-01-01

    The 52 abstracts in these 29 serial issues describe innovative approaches to teaching and learning in the community college. Sample topics include reading motivation, barriers to academic success, the learning environment, writing skills, leadership in the criminal justice profession, role-playing strategies, cooperative education, distance…

  5. Abstract Journal Concept Being Examined

    ERIC Educational Resources Information Center

    Somerville, Brendan F.

    1972-01-01

    In order to control the information explosion, some European chemical groups are studying the idea of abandoning full publication in printed form of all primary journals and, in their place, substituting a new form of abstract journal combined with a microfilm record of full scientific papers. (Author/CP)

  6. Metaphoric Images from Abstract Concepts.

    ERIC Educational Resources Information Center

    Vizmuller-Zocco, Jana

    1992-01-01

    Discusses children's use of metaphors to create meaning, using as an example the pragmatic and "scientific" ways in which preschool children explain thunder and lightning to themselves. Argues that children are being shortchanged by modern scientific notions of abstractness and that they should be encouraged to create their own explanations of…

  7. ERGONOMICS ABSTRACTS 48347-48982.

    ERIC Educational Resources Information Center

    Ministry of Technology, London (England). Warren Spring Lab.

    IN THIS COLLECTION OF ERGONOMICS ABSTRACTS AND ANNOTATIONS THE FOLLOWING AREAS OF CONCERN ARE REPRESENTED--GENERAL REFERENCES, METHODS, FACILITIES, AND EQUIPMENT RELATING TO ERGONOMICS, SYSTEMS OF MAN AND MACHINES, VISUAL, AUDITORY, AND OTHER SENSORY INPUTS AND PROCESSES (INCLUDING SPEECH AND INTELLIGIBILITY), INPUT CHANNELS, BODY MEASUREMENTS,…

  8. Does "Social Work Abstracts" Work?

    ERIC Educational Resources Information Center

    Holden, Gary; Barker, Kathleen; Covert-Vail, Lucinda; Rosenberg, Gary; Cohen, Stephanie A.

    2008-01-01

    Objective: The current study seeks to provide estimates of the adequacy of journal coverage in the Social Work Abstracts (SWA) database. Method: A total of 23 journals listed in the Journal Citation Reports social work category during the 1997 to 2005 period were selected for study. Issue-level coverage estimates were obtained for SWA and…

  9. Manpower Management Studies: Selected Abstracts.

    ERIC Educational Resources Information Center

    Ryerson, William R., Comp.

    This bibliography contains 58 selected abstracts of research reports dating back to 1964 on the general subject of manpower management. It was prepared from a search of the National Technical Information Service data base of more than 300,000 documents submitted by agencies of the Federal Government and also by private organizations or individuals…

  10. The Theatre Audience: An Abstraction.

    ERIC Educational Resources Information Center

    Campbell, Paul Newell

    1981-01-01

    Argues that theater is aimed at and presented to an ideal or abstract audience. Discusses the implications of performing for an actual audience, adaptation to various audiences, and the concept of the audience as an evaluative device. (See CS 705 536.) (JMF)

  11. Chemical Abstracts' Document Delivery Service.

    ERIC Educational Resources Information Center

    Rollins, Stephen

    1984-01-01

    The Document Delivery Service offered by Chemical Abstracts is described in terms of the DIALORDER option on the Dialog information retrieval system, mail requests, and requests transmitted through OCLC's Interlibrary Loan system. Transmission costs, success rates, delivery rates, and other considerations in utilizing the service are included.…

  12. Fostering Formal Commutativity Knowledge with Approximate Arithmetic

    PubMed Central

    Hansen, Sonja Maria; Haider, Hilde; Eichler, Alexandra; Godau, Claudia; Frensch, Peter A.; Gaschler, Robert

    2015-01-01

    How can we enhance the understanding of abstract mathematical principles in elementary school? Different studies found out that nonsymbolic estimation could foster subsequent exact number processing and simple arithmetic. Taking the commutativity principle as a test case, we investigated if the approximate calculation of symbolic commutative quantities can also alter the access to procedural and conceptual knowledge of a more abstract arithmetic principle. Experiment 1 tested first graders who had not been instructed about commutativity in school yet. Approximate calculation with symbolic quantities positively influenced the use of commutativity-based shortcuts in formal arithmetic. We replicated this finding with older first graders (Experiment 2) and third graders (Experiment 3). Despite the positive effect of approximation on the spontaneous application of commutativity-based shortcuts in arithmetic problems, we found no comparable impact on the application of conceptual knowledge of the commutativity principle. Overall, our results show that the usage of a specific arithmetic principle can benefit from approximation. However, the findings also suggest that the correct use of certain procedures does not always imply conceptual understanding. Rather, the conceptual understanding of commutativity seems to lag behind procedural proficiency during elementary school. PMID:26560311

  13. Fostering Formal Commutativity Knowledge with Approximate Arithmetic.

    PubMed

    Hansen, Sonja Maria; Haider, Hilde; Eichler, Alexandra; Godau, Claudia; Frensch, Peter A; Gaschler, Robert

    2015-01-01

    How can we enhance the understanding of abstract mathematical principles in elementary school? Different studies found out that nonsymbolic estimation could foster subsequent exact number processing and simple arithmetic. Taking the commutativity principle as a test case, we investigated if the approximate calculation of symbolic commutative quantities can also alter the access to procedural and conceptual knowledge of a more abstract arithmetic principle. Experiment 1 tested first graders who had not been instructed about commutativity in school yet. Approximate calculation with symbolic quantities positively influenced the use of commutativity-based shortcuts in formal arithmetic. We replicated this finding with older first graders (Experiment 2) and third graders (Experiment 3). Despite the positive effect of approximation on the spontaneous application of commutativity-based shortcuts in arithmetic problems, we found no comparable impact on the application of conceptual knowledge of the commutativity principle. Overall, our results show that the usage of a specific arithmetic principle can benefit from approximation. However, the findings also suggest that the correct use of certain procedures does not always imply conceptual understanding. Rather, the conceptual understanding of commutativity seems to lag behind procedural proficiency during elementary school. PMID:26560311

  14. Countably QC-Approximating Posets

    PubMed Central

    Mao, Xuxin; Xu, Luoshan

    2014-01-01

    As a generalization of countably C-approximating posets, the concept of countably QC-approximating posets is introduced. With the countably QC-approximating property, some characterizations of generalized completely distributive lattices and generalized countably approximating posets are given. The main results are as follows: (1) a complete lattice is generalized completely distributive if and only if it is countably QC-approximating and weakly generalized countably approximating; (2) a poset L having countably directed joins is generalized countably approximating if and only if the lattice σc(L)op of all σ-Scott-closed subsets of L is weakly generalized countably approximating. PMID:25165730

  15. Object Classification via Planar Abstraction

    NASA Astrophysics Data System (ADS)

    Oesau, Sven; Lafarge, Florent; Alliez, Pierre

    2016-06-01

    We present a supervised machine learning approach for classification of objects from sampled point data. The main idea consists in first abstracting the input object into planar parts at several scales, then discriminate between the different classes of objects solely through features derived from these planar shapes. Abstracting into planar shapes provides a means to both reduce the computational complexity and improve robustness to defects inherent to the acquisition process. Measuring statistical properties and relationships between planar shapes offers invariance to scale and orientation. A random forest is then used for solving the multiclass classification problem. We demonstrate the potential of our approach on a set of indoor objects from the Princeton shape benchmark and on objects acquired from indoor scenes and compare the performance of our method with other point-based shape descriptors.

  16. An Abstract Plan Preparation Language

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Munoz, Cesar A.

    2006-01-01

    This paper presents a new planning language that is more abstract than most existing planning languages such as the Planning Domain Definition Language (PDDL) or the New Domain Description Language (NDDL). The goal of this language is to simplify the formal analysis and specification of planning problems that are intended for safety-critical applications such as power management or automated rendezvous in future manned spacecraft. The new language has been named the Abstract Plan Preparation Language (APPL). A translator from APPL to NDDL has been developed in support of the Spacecraft Autonomy for Vehicles and Habitats Project (SAVH) sponsored by the Explorations Technology Development Program, which is seeking to mature autonomy technology for application to the new Crew Exploration Vehicle (CEV) that will replace the Space Shuttle.

  17. Approximate Bayesian multibody tracking.

    PubMed

    Lanz, Oswald

    2006-09-01

    Visual tracking of multiple targets is a challenging problem, especially when efficiency is an issue. Occlusions, if not properly handled, are a major source of failure. Solutions supporting principled occlusion reasoning have been proposed but are yet unpractical for online applications. This paper presents a new solution which effectively manages the trade-off between reliable modeling and computational efficiency. The Hybrid Joint-Separable (HJS) filter is derived from a joint Bayesian formulation of the problem, and shown to be efficient while optimal in terms of compact belief representation. Computational efficiency is achieved by employing a Markov random field approximation to joint dynamics and an incremental algorithm for posterior update with an appearance likelihood that implements a physically-based model of the occlusion process. A particle filter implementation is proposed which achieves accurate tracking during partial occlusions, while in cases of complete occlusion, tracking hypotheses are bound to estimated occlusion volumes. Experiments show that the proposed algorithm is efficient, robust, and able to resolve long-term occlusions between targets with identical appearance. PMID:16929730

  18. Cryogenic foam insulation: Abstracted publications

    NASA Technical Reports Server (NTRS)

    Williamson, F. R.

    1977-01-01

    A group of documents were chosen and abstracted which contain information on the properties of foam materials and on the use of foams as thermal insulation at cryogenic temperatures. The properties include thermal properties, mechanical properties, and compatibility properties with oxygen and other cryogenic fluids. Uses of foams include applications as thermal insulation for spacecraft propellant tanks, and for liquefied natural gas storage tanks and pipelines.

  19. Concrete and abstract Voronoi diagrams

    SciTech Connect

    Klein, R. )

    1989-01-01

    The Voronoi diagram of a set of sites is a partition of the plane into regions, one to each site, such that the region of each site contains all points of the plane that are closer to this site than to the other ones. Such partitions are of great importance to computer science and many other fields. The challenge is to compute Voronoi diagrams quickly. The problem is that their structure depends on the notion of distance and the sort of site. In this book the author proposes a unifying approach by introducing abstract Voronoi diagrams. These are based on the concept of bisecting curves which are required to have some simple properties that are actually possessed by most bisectors of concrete Voronoi diagrams. Abstract Voronoi diagrams can be computed efficiently and there exists a worst-case efficient algorithm of divide-and-conquer type that applies to all abstract Voronoi diagrams satisfying a certain constraint. The author shows that this constraint is fulfilled by the concrete diagrams based no large classes of metrics in the plane.

  20. Approximation by hinge functions

    SciTech Connect

    Faber, V.

    1997-05-01

    Breiman has defined {open_quotes}hinge functions{close_quotes} for use as basis functions in least squares approximations to data. A hinge function is the max (or min) function of two linear functions. In this paper, the author assumes the existence of smooth function f(x) and a set of samples of the form (x, f(x)) drawn from a probability distribution {rho}(x). The author hopes to find the best fitting hinge function h(x) in the least squares sense. There are two problems with this plan. First, Breiman has suggested an algorithm to perform this fit. The author shows that this algorithm is not robust and also shows how to create examples on which the algorithm diverges. Second, if the author tries to use the data to minimize the fit in the usual discrete least squares sense, the functional that must be minimized is continuous in the variables, but has a derivative which jumps at the data. This paper takes a different approach. This approach is an example of a method that the author has developed called {open_quotes}Monte Carlo Regression{close_quotes}. (A paper on the general theory is in preparation.) The author shall show that since the function f is continuous, the analytic form of the least squares equation is continuously differentiable. A local minimum is solved for by using Newton`s method, where the entries of the Hessian are estimated directly from the data by Monte Carlo. The algorithm has the desirable properties that it is quadratically convergent from any starting guess sufficiently close to a solution and that each iteration requires only a linear system solve.

  1. Multijet final states: exact results and the leading pole approximation

    SciTech Connect

    Ellis, R.K.; Owens, J.F.

    1984-09-01

    Exact results for the process gg ..-->.. ggg are compared with those obtained using the leading pole approximation. Regions of phase space where the approximation breaks down are discussed. A specific example relevant for background estimates to W boson production is presented. It is concluded that in this instance the leading pole approximation may underestimate the standard QCD background by more than a factor of two in certain kinematic regions of physical interest.

  2. Youth Studies Abstracts. Vol. 4 No. 3.

    ERIC Educational Resources Information Center

    Youth Studies Abstracts, 1985

    1985-01-01

    This volume contains 169 abstracts of documents dealing with youth and educational programs for youth. Included in the volume are 97 abstracts of documents dealing with social and educational developments; 56 abstracts of program reports, reviews, and evaluations; and 16 abstracts of program materials. Abstracts are grouped according to the…

  3. Phonological abstraction without phonemes in speech perception.

    PubMed

    Mitterer, Holger; Scharenborg, Odette; McQueen, James M

    2013-11-01

    Recent evidence shows that listeners use abstract prelexical units in speech perception. Using the phenomenon of lexical retuning in speech processing, we ask whether those units are necessarily phonemic. Dutch listeners were exposed to a Dutch speaker producing ambiguous phones between the Dutch syllable-final allophones approximant [r] and dark [l]. These ambiguous phones replaced either final /r/ or final /l/ in words in a lexical-decision task. This differential exposure affected perception of ambiguous stimuli on the same allophone continuum in a subsequent phonetic-categorization test: Listeners exposed to ambiguous phones in /r/-final words were more likely to perceive test stimuli as /r/ than listeners with exposure in /l/-final words. This effect was not found for test stimuli on continua using other allophones of /r/ and /l/. These results confirm that listeners use phonological abstraction in speech perception. They also show that context-sensitive allophones can play a role in this process, and hence that context-insensitive phonemes are not necessary. We suggest there may be no one unit of perception. PMID:23973464

  4. Background sources at PEP

    SciTech Connect

    Lynch, H.; Schwitters, R.F.; Toner, W.T.

    1988-01-01

    Important sources of background for PEP experiments are studied. Background particles originate from high-energy electrons and positrons which have been lost from stable orbits, ..gamma..-rays emitted by the primary beams through bremsstrahlung in the residual gas, and synchrotron radiation x-rays. The effect of these processes on the beam lifetime are calculated and estimates of background rates at the interaction region are given. Recommendations for the PEP design, aimed at minimizing background are presented. 7 figs., 4 tabs.

  5. Building Background Knowledge

    ERIC Educational Resources Information Center

    Neuman, Susan B.; Kaefer, Tanya; Pinkham, Ashley

    2014-01-01

    This article make a case for the importance of background knowledge in children's comprehension. It suggests that differences in background knowledge may account for differences in understanding text for low- and middle-income children. It then describes strategies for building background knowledge in the age of common core standards.

  6. Leadership Abstracts, Volume 2, Numbers 1-21, 1989.

    ERIC Educational Resources Information Center

    Doucette, Don, Ed.

    This series of abstracts from the League for Innovation in the Community College and the Community College Leadership Program is published approximately bimonthly and distributed to the chief executive officer of every two-year college in the United States and Canada. Addressing a variety of topics of interest to community college administrators,…

  7. A Program Abstract for Translating Inkprint into Braille by Computer.

    ERIC Educational Resources Information Center

    Seims, John R.

    A program abstract which corresponds to the computer program for braille translation at the American Printing House for the Blind presents an approach to computer processing of inkprint into braille including input, output, storage areas, and processing steps. The program runs on a 709 data processing system, requires approximately 9,400 36-bit…

  8. Leadership Abstracts, Volume 3, Numbers 1-20, 1990.

    ERIC Educational Resources Information Center

    Doucette, Don, Ed.

    This series of abstracts from the League for Innovation in the Community College and the Community College Leadership Program is published approximately bimonthly and distributed to the chief executive officer of every two-year college in the United States and Canada. Addressing a variety of topics of interest to community college administrators,…

  9. Operating System Abstraction Layer (OSAL)

    NASA Technical Reports Server (NTRS)

    Yanchik, Nicholas J.

    2007-01-01

    This viewgraph presentation reviews the concept of the Operating System Abstraction Layer (OSAL) and its benefits. The OSAL is A small layer of software that allows programs to run on many different operating systems and hardware platforms It runs independent of the underlying OS & hardware and it is self-contained. The benefits of OSAL are that it removes dependencies from any one operating system, promotes portable, reusable flight software. It allows for Core Flight software (FSW) to be built for multiple processors and operating systems. The presentation discusses the functionality, the various OSAL releases, and describes the specifications.

  10. IEEE conference record--Abstracts

    SciTech Connect

    Not Available

    1992-01-01

    The following topics were covered in this meeting: basic plasma phenomena and plasma waves; plasma diagnostics; space plasma diagnostics; magnetic fusion; electron, ion and plasma sources; intense electron and ion beams; intense beam microwaves; fast wave M/W devices; microwave plasma interactions; plasma focus; ultrafast Z-pinches; plasma processing; electrical gas discharges; fast opening switches; magnetohydrodynamics; electromagnetic and electrothermal launchers; x-ray lasers; computational plasma science; solid state plasmas and switches; environmental/energy issues in plasma science; vacuum electronics; plasmas for lighting; gaseous electronics; and ball lightning and other spherical plasmas. Separate abstracts were prepared for 278 papers of this conference.

  11. Characterizing inflationary perturbations: The uniform approximation

    SciTech Connect

    Habib, Salman; Heinen, Andreas; Heitmann, Katrin; Jungman, Gerard; Molina-Paris, Carmen

    2004-10-15

    The spectrum of primordial fluctuations from inflation can be obtained using a mathematically controlled, and systematically extendable, uniform approximation. Closed-form expressions for power spectra and spectral indices may be found without making explicit slow-roll assumptions. Here we provide details of our previous calculations, extend the results beyond leading-order in the approximation, and derive general error bounds for power spectra and spectral indices. Already at next-to-leading-order, the errors in calculating the power spectrum are less than a percent. This meets the accuracy requirement for interpreting next-generation cosmic microwave background observations.

  12. Abstract Expression Grammar Symbolic Regression

    NASA Astrophysics Data System (ADS)

    Korns, Michael F.

    This chapter examines the use of Abstract Expression Grammars to perform the entire Symbolic Regression process without the use of Genetic Programming per se. The techniques explored produce a symbolic regression engine which has absolutely no bloat, which allows total user control of the search space and output formulas, which is faster, and more accurate than the engines produced in our previous papers using Genetic Programming. The genome is an all vector structure with four chromosomes plus additional epigenetic and constraint vectors, allowing total user control of the search space and the final output formulas. A combination of specialized compiler techniques, genetic algorithms, particle swarm, aged layered populations, plus discrete and continuous differential evolution are used to produce an improved symbolic regression sytem. Nine base test cases, from the literature, are used to test the improvement in speed and accuracy. The improved results indicate that these techniques move us a big step closer toward future industrial strength symbolic regression systems.

  13. Toward Millimagnitude Photometric Calibration (Abstract)

    NASA Astrophysics Data System (ADS)

    Dose, E.

    2014-12-01

    (Abstract only) Asteroid roation, exoplanet transits, and similar measurements will increasingly call for photometric precisions better than about 10 millimagnitudes, often between nights and ideally between distant observers. The present work applies detailed spectral simulations to test popular photometric calibration practices, and to test new extensions of these practices. Using 107 synthetic spectra of stars of diverse colors, detailed atmospheric transmission spectra computed by solar-energy software, realistic spectra of popular astronomy gear, and the option of three sources of noise added at realistic millimagnitude levels, we find that certain adjustments to current calibration practices can help remove small systematic errors, especially for imperfect filters, high airmasses, and possibly passing thin cirrus clouds.

  14. Experience with abstract notation one

    NASA Technical Reports Server (NTRS)

    Harvey, James D.; Weaver, Alfred C.

    1990-01-01

    The development of computer science has produced a vast number of machine architectures, programming languages, and compiler technologies. The cross product of these three characteristics defines the spectrum of previous and present data representation methodologies. With regard to computer networks, the uniqueness of these methodologies presents an obstacle when disparate host environments are to be interconnected. Interoperability within a heterogeneous network relies upon the establishment of data representation commonality. The International Standards Organization (ISO) is currently developing the abstract syntax notation one standard (ASN.1) and the basic encoding rules standard (BER) that collectively address this problem. When used within the presentation layer of the open systems interconnection reference model, these two standards provide the data representation commonality required to facilitate interoperability. The details of a compiler that was built to automate the use of ASN.1 and BER are described. From this experience, insights into both standards are given and potential problems relating to this development effort are discussed.

  15. Abstraction Planning in Real Time

    NASA Technical Reports Server (NTRS)

    Washington, Richard

    1994-01-01

    When a planning agent works in a complex, real-world domain, it is unable to plan for and store all possible contingencies and problem situations ahead of time. The agent needs to be able to fall back on an ability to construct plans at run time under time constraints. This thesis presents a method for planning at run time that incrementally builds up plans at multiple levels of abstraction. The plans are continually updated by information from the world, allowing the planner to adjust its plan to a changing world during the planning process. All the information is represented over intervals of time, allowing the planner to reason about durations, deadlines, and delays within its plan. In addition to the method, the thesis presents a formal model of the planning process and uses the model to investigate planning strategies. The method has been implemented, and experiments have been run to validate the overall approach and the theoretical model.

  16. Abstraction Planning in Real Time

    NASA Technical Reports Server (NTRS)

    Washington, R.

    1994-01-01

    When a planning agent works in a complex, real-world domain, it is unable to plan for and store all possible contingencies and problem situations ahead of time. This thesis presents a method for planning a run time that incrementally builds up plans at multiple levels of abstraction. The plans are continually updated by information from the world, allowing the planner to adjust its plan to a changing world during the planning process. All the information is represented over intervals of time, allowing the planner to reason about durations, deadlines, and delays within its plan. In addition to the method, the thesis presents a formal model of the planning process and uses the model to investigate planning strategies.

  17. The Cosmic Background Explorer.

    ERIC Educational Resources Information Center

    Gulkis, Samuel; And Others

    1990-01-01

    Outlines the Cosmic Background Explorer (COBE) mission to measure celestial radiation. Describes the instruments used and experiments involving differential microwave radiometers, and a far infrared absolute spectrophotometer. (YP)

  18. Concrete Model Checking with Abstract Matching and Refinement

    NASA Technical Reports Server (NTRS)

    Pasareanu Corina S.; Peianek Radek; Visser, Willem

    2005-01-01

    We propose an abstraction-based model checking method which relies on refinement of an under-approximation of the feasible behaviors of the system under analysis. The method preserves errors to safety properties, since all analyzed behaviors are feasible by definition. The method does not require an abstract transition relation to he generated, but instead executes the concrete transitions while storing abstract versions of the concrete states, as specified by a set of abstraction predicates. For each explored transition. the method checks, with the help of a theorem prover, whether there is any loss of precision introduced by abstraction. The results of these checks are used to decide termination or to refine the abstraction, by generating new abstraction predicates. If the (possibly infinite) concrete system under analysis has a finite bisimulation quotient, then the method is guaranteed to eventually explore an equivalent finite bisimilar structure. We illustrate the application of the approach for checking concurrent programs. We also show how a lightweight variant can be used for efficient software testing.

  19. Impairment of shooting performance by background complexity and motion.

    PubMed

    Caroux, Loïc; Le Bigot, Ludovic; Vibert, Nicolas

    2015-01-01

    In many visual displays such as virtual environments, human tasks involve objects superimposed on both complex and moving backgrounds. However, most studies investigated the influence of background complexity or background motion in isolation. Two experiments were designed to investigate the joint influences of background complexity and lateral motion on a simple shooting task typical of video games. Participants had to perform the task on the moving and static versions of backgrounds of three levels of complexity, while their eye movements were recorded. The backgrounds displayed either an abstract (Experiment 1) or a naturalistic (Experiment 2) virtual environment. The results showed that performance was impaired by background motion in both experiments. The effects of motion and complexity were additive for the abstract background and multiplicative for the naturalistic background. Eye movement recordings showed that performance impairments reflected at least in part the impact of the background visual features on gaze control. PMID:25384639

  20. Educational Technology in Micro-Teaching Preparation. Abstract.

    ERIC Educational Resources Information Center

    Walters, Charles D.

    This paper is an abstract of a longer paper which was read at the American Educational Research Association (AERA) Annual Meeting in 1974. It begins with a brief background discussion on microteaching and goes on to list the teaching skills which microteaching develops. A brief summary of the research on microteaching is then given. The abstract…

  1. Bilingual/Bicultural Education: Titles and Abstracts of Doctoral Dissertations.

    ERIC Educational Resources Information Center

    California State Univ., Los Angeles. National Dissemination and Assessment Center.

    Dissertation abstracts describing research on a wide variety of topics in bilingual education are presented. This publication is designed to provide background material for bilingual educators as well as practical procedures for bilingual teachers, administrators, counselors, and evaluators. The titles were acquired by using the two broad…

  2. An approximation theory for the identification of linear thermoelastic systems

    NASA Technical Reports Server (NTRS)

    Rosen, I. G.; Su, Chien-Hua Frank

    1990-01-01

    An abstract approximation framework and convergence theory for the identification of thermoelastic systems is developed. Starting from an abstract operator formulation consisting of a coupled second order hyperbolic equation of elasticity and first order parabolic equation for heat conduction, well-posedness is established using linear semigroup theory in Hilbert space, and a class of parameter estimation problems is then defined involving mild solutions. The approximation framework is based upon generic Galerkin approximation of the mild solutions, and convergence of solutions of the resulting sequence of approximating finite dimensional parameter identification problems to a solution of the original infinite dimensional inverse problem is established using approximation results for operator semigroups. An example involving the basic equations of one dimensional linear thermoelasticity and a linear spline based scheme are discussed. Numerical results indicate how the approach might be used in a study of damping mechanisms in flexible structures.

  3. Backgrounds in Language.

    ERIC Educational Resources Information Center

    Maxwell, John C.; Long, Barbara K.

    "Backgrounds in Language," a field-tested inservice course designed for use by groups of 15 or 25 language arts teachers, provides the subject matter background teachers need to make informed decisions about what curriculum materials to use in what way, at what time, and with which students. The course is comprised of eight 2-hour sessions,…

  4. Correlators in nontrivial backgrounds

    SciTech Connect

    Mello Koch, Robert de; Ives, Norman; Stephanou, Michael

    2009-01-15

    Operators in N=4 super Yang-Mills theory with an R-charge of O(N{sup 2}) are dual to backgrounds which are asymtotically AdS{sub 5}xS{sup 5}. In this article we develop efficient techniques that allow the computation of correlation functions in these backgrounds. We find that (i) contractions between fields in the string words and fields in the operator creating the background are the field theory accounting of the new geometry, (ii) correlation functions of probes in these backgrounds are given by the free field theory contractions but with rescaled propagators and (iii) in these backgrounds there are no open string excitations with their special end point interactions; we have only closed string excitations.

  5. An abstract approach to music.

    SciTech Connect

    Kaper, H. G.; Tipei, S.

    1999-04-19

    In this article we have outlined a formal framework for an abstract approach to music and music composition. The model is formulated in terms of objects that have attributes, obey relationships, and are subject to certain well-defined operations. The motivation for this approach uses traditional terms and concepts of music theory, but the approach itself is formal and uses the language of mathematics. The universal object is an audio wave; partials, sounds, and compositions are special objects, which are placed in a hierarchical order based on time scales. The objects have both static and dynamic attributes. When we realize a composition, we assign values to each of its attributes: a (scalar) value to a static attribute, an envelope and a size to a dynamic attribute. A composition is then a trajectory in the space of aural events, and the complex audio wave is its formal representation. Sounds are fibers in the space of aural events, from which the composer weaves the trajectory of a composition. Each sound object in turn is made up of partials, which are the elementary building blocks of any music composition. The partials evolve on the fastest time scale in the hierarchy of partials, sounds, and compositions. The ideas outlined in this article are being implemented in a digital instrument for additive sound synthesis and in software for music composition. A demonstration of some preliminary results has been submitted by the authors for presentation at the conference.

  6. 1986 annual information meeting. Abstracts

    SciTech Connect

    Not Available

    1986-01-01

    Abstracts are presented for the following papers: Geohydrological Research at the Y-12 Plant (C.S. Haase); Ecological Impacts of Waste Disposal Operations in Bear Creek Valley Near the Y-12 Plant (J.M. Loar); Finite Element Simulation of Subsurface Contaminant Transport: Logistic Difficulties in Handling Large Field Problems (G.T. Yeh); Dynamic Compaction of a Radioactive Waste Burial Trench (B.P. Spalding); Comparative Evaluation of Potential Sites for a High-Level Radioactive Waste Repository (E.D. Smith); Changing Priorities in Environmental Assessment and Environmental Compliance (R.M. Reed); Ecology, Ecotoxicology, and Ecological Risk Assessment (L.W. Barnthouse); Theory and Practice in Uncertainty Analysis from Ten Years of Practice (R.H. Gardner); Modeling Landscape Effects of Forest Decline (V.H. Dale); Soil Nitrogen and the Global Carbon Cycle (W.M. Post); Maximizing Wood Energy Production in Short-Rotation Plantations: Effect of Initial Spacing and Rotation Length (L.L. Wright); and Ecological Communities and Processes in Woodland Streams Exhibit Both Direct and Indirect Effects of Acidification (J.W. Elwood).

  7. Background Underground at WIPP

    NASA Astrophysics Data System (ADS)

    Esch, Ernst-Ingo; Hime, A.; Bowles, T. J.

    2001-04-01

    Recent interest to establish a dedicated underground laboratory in the United States prompted an experimental program at to quantify the enviromental backgrounds underground at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, New Mexico. An outline of this program is provided along with recent experimental data on the cosmic ray muon flux at the 650 meter level of WIPP. The implications of the cosmic ray muon and fast neutron background at WIPP will be discussed in the context of new generation, low background experiments envisioned in the future.

  8. The cosmic neutrino background

    NASA Technical Reports Server (NTRS)

    Dar, Arnon

    1991-01-01

    The cosmic neutrino background is expected to consist of relic neutrinos from the big bang, of neutrinos produced during nuclear burning in stars, of neutrinos released by gravitational stellar collapse, and of neutrinos produced by cosmic ray interactions with matter and radiation in the interstellar and intergalactic medium. Formation of baryonic dark matter in the early universe, matter-antimatter annihilation in a baryonic symmetric universe, and dark matter annihilation could have also contributed significantly to the cosmic neutrino background. The purpose of this paper is to review the properties of these cosmic neutrino backgrounds, the indirect evidence for their existence, and the prospects for their detection.

  9. Adaptive background model

    NASA Astrophysics Data System (ADS)

    Lu, Xiaochun; Xiao, Yijun; Chai, Zhi; Wang, Bangping

    2007-11-01

    An adaptive background model aiming at outdoor vehicle detection is presented in this paper. This model is an improved model of PICA (pixel intensity classification algorithm), it classifies pixels into K-distributions by color similarity, and then a hypothesis that the background pixel color appears in image sequence with a high frequency is used to evaluate all the distributions to determine which presents the current background color. As experiments show, the model presented in this paper is a robust, adaptive and flexible model, which can deal with situations like camera motions, lighting changes and so on.

  10. The GLAST Background Model

    SciTech Connect

    Ormes, J.F.; Atwood, W.; Burnett, T.; Grove, E.; Longo, F.; McEnery, J.; Mizuno, T.; Ritz, S.; /NASA, Goddard

    2007-10-17

    In order to estimate the ability of the GLAST/LAT to reject unwanted background of charged particles, optimize the on-board processing, size the required telemetry and optimize the GLAST orbit, we developed a detailed model of the background particles that would affect the LAT. In addition to the well-known components of the cosmic radiation, we included splash and reentrant components of protons, electrons (e+ and e-) from 10 MeV and beyond as well as the albedo gamma rays produced by cosmic ray interactions with the atmosphere. We made estimates of the irreducible background components produced by positrons and hadrons interacting in the multilayered micrometeorite shield and spacecraft surrounding the LAT and note that because the orbital debris has increased, the shielding required and hence the background are larger than were present in EGRET. Improvements to the model are currently being made to include the east-west effect.

  11. The GLAST Background Model

    SciTech Connect

    Ormes, J. F.; Atwood, W.; Burnett, T.; Grove, E.; Longo, F.; McEnery, J.; Ritz, S.; Mizuno, T.

    2007-07-12

    In order to estimate the ability of the GLAST/LAT to reject unwanted background of charged particles, optimize the on-board processing, size the required telemetry and optimize the GLAST orbit, we developed a detailed model of the background particles that would affect the LAT. In addition to the well-known components of the cosmic radiation, we included splash and reentrant components of protons, electrons (e+ and e-) from 10 MeV and beyond as well as the albedo gamma rays produced by cosmic ray interactions with the atmosphere. We made estimates of the irreducible background components produced by positrons and hadrons interacting in the multilayered micrometeorite shield and spacecraft surrounding the LAT and note that because the orbital debris has increased, the shielding required and hence the background are larger than were present in EGRET. Improvements to the model are currently being made to include the east-west effect.

  12. Numerical Stability and Convergence of Approximate Methods for Conservation Laws

    NASA Astrophysics Data System (ADS)

    Galkin, V. A.

    We present the new approach to background of approximate methods convergence based on functional solutions theory for conservation laws. The applications to physical kinetics, gas and fluid dynamics are considered.

  13. Abstraction and reformulation in artificial intelligence.

    PubMed Central

    Holte, Robert C.; Choueiry, Berthe Y.

    2003-01-01

    This paper contributes in two ways to the aims of this special issue on abstraction. The first is to show that there are compelling reasons motivating the use of abstraction in the purely computational realm of artificial intelligence. The second is to contribute to the overall discussion of the nature of abstraction by providing examples of the abstraction processes currently used in artificial intelligence. Although each type of abstraction is specific to a somewhat narrow context, it is hoped that collectively they illustrate the richness and variety of abstraction in its fullest sense. PMID:12903653

  14. Annotating user-defined abstractions for optimization

    SciTech Connect

    Quinlan, D; Schordan, M; Vuduc, R; Yi, Q

    2005-12-05

    This paper discusses the features of an annotation language that we believe to be essential for optimizing user-defined abstractions. These features should capture semantics of function, data, and object-oriented abstractions, express abstraction equivalence (e.g., a class represents an array abstraction), and permit extension of traditional compiler optimizations to user-defined abstractions. Our future work will include developing a comprehensive annotation language for describing the semantics of general object-oriented abstractions, as well as automatically verifying and inferring the annotated semantics.

  15. DOE-NABIR PI Workshop: Abstracts 2003

    SciTech Connect

    Various

    2003-01-28

    The mission of the NABIR program is to provide the fundamental science that will serve as the basis for the development of cost-effective bioremediation and long-term stewardship of radionuclides and metals in the subsurface at DOE sites. The focus of the program is on strategies leading to long-term immobilization of contaminants in situ to reduce the risk to humans and the environment. Contaminants of special interest are uranium, technetium, plutonium, chromium, and mercury. The focus of the NABIR program is on the bioremediation of these contaminants in the subsurface below the root zone, including both vadose and saturated zones. The program consists of four interrelated Science Elements (Biotransformation, Community Dynamics/Microbial Ecology, Biomolecular Science and Engineering, and Biogeochemistry). The program also has a cross-cutting Assessment Element that supports development of innovative approaches and technologies to support the science elements. An element called Bioremediation and its Societal Implications and Concerns (BASIC) addresses potential societal issues of implementing NABIR scientific findings. The material presented at this year's workshop focuses on approximately 60 research projects funded in FY 2000-2003 by the Environmental Remediation Sciences Division in DOE's Office of Biological and Environmental Research (BER) in the Office of Science. Abstracts of NABIR research projects are provided in this book.

  16. DOE NABIR PI Workshop: Abstracts 2002

    SciTech Connect

    Hawkes , Dan

    2002-01-09

    The mission of the NABIR program is to provide the fundamental science that will serve as the basis for the development of cost-effective bioremediation and long-term stewardship of radionuclides and metals in the subsurface at DOE sites. The focus of the program is on strategies leading to long-term immobilization of contaminants in place to reduce the risk to humans and the environment. Contaminants of special interest are uranium, technetium, plutonium, chromium, and mercury. The focus of the NABIR program is on the bioremediation of these contaminants in the subsurface below the root zone, including both vadose and saturated zones. The program is implemented through four interrelated scientific research elements (Biogeochemistry, Biomolecular Science and Engineering, Biotransformation, and Community Dynamics/Microbial Ecology); and through an element called Bioremediation and its Societal Implications and Concerns (BASIC), which addresses societal issues and potential concerns of stakeholders. The material presented at this year's workshop focuses on approximately 60 research projects funded in FY 2000-2002 by DOE's Office of Biological and Environmental Research (BER). Abstracts of NABIR research projects are provided in this book.

  17. Refining a taxonomy for guideline implementation: results of an exercise in abstract classification

    PubMed Central

    2013-01-01

    Background To better understand the efficacy of various implementation strategies, improved methods for describing and classifying the nature of these strategies are urgently required. The aim of this study was to develop and pilot the feasibility of a taxonomy to classify the nature and content of implementation strategies. Methods A draft implementation taxonomy was developed based on the Cochrane Effective Practice and Organisation of Care (EPOC) data collection checklist. The draft taxonomy had four domains (professional, financial, organisational and regulatory) covering 49 distinct strategies. We piloted the draft taxonomy by using it to classify the implementation strategies described in the conference abstracts of the implementation stream of the 2010 Guideline International Network Conference. Five authors classified the strategies in each abstract individually. Final categorisation was then carried out in a face-to-face consensus meeting involving three authors. Results The implementation strategies described in 71 conference abstracts were classified. Approximately 15.5% of abstracts utilised strategies that could not be categorised using the draft taxonomy. Of those strategies that could be categorised, the majority were professionally focused (57%). A total of 41% of projects used only one implementation strategy, with 29% using two and 31% three or more. The three most commonly used strategies were changes in quality assurance, quality improvement and/or performance measurement systems, changes in information and communication technology, and distribution of guideline materials (via hard-copy, audio-visual and/or electronic means). Conclusions Further refinement of the draft taxonomy is required to provide hierarchical dimensions and granularity, particularly in the areas of patient-focused interventions, those concerned with audit and feedback and quality improvement, and electronic forms of implementation, including electronic decision support. PMID

  18. 0.625" FPPW Abstract

    NASA Technical Reports Server (NTRS)

    Littell, Justin

    2015-01-01

    Friction Pull Plug Welding (FPPW) is a solid-state process that is the primary close out method for Self- Reacting Friction Stir Welding (SR-FSW). This process uses a servo hydraulic machine to spin an aluminum plug to several thousand revolutions per minute and pull the plug with several thousand pound force into an aluminum piece of material. This process, which has been around for approximately a decade, has proven to be a very difficult process to develop. There are large number of variables with interactions and correlations that are difficult to detect. Historically this method only provided good results on aluminum material up to 0.327" thick. The SLS rocket required weld land configurations of up to 0.625" thick. This not only pushed the limits of the process but also of the tools procured for materials 1/2 as thick. Ultimate Tensile Results was typically the response used for FPPW input variables. The problem was there were multiple processes including, welding, post weld machining, Non Destructive Evaluation, specimen fabrication and mechanical testing between the FPPW inputs and the mechanical test results. This only compiled the list of variables and made the process of FPPW even more difficult to develop. This presentation and paper describes the new process development methodology, which uses the FPPW tool's feedback to observe the process and develop it systematically. It captures 6 months and 600 plugs worth of work using only the tool's feedback as a response to the process. This presentation describes the solution to the issue, a solution whose methodology could apply to a variety of other processes.

  19. Micromagnetics at submicron dimensions (abstract)

    NASA Astrophysics Data System (ADS)

    Slonczewski, J. C.

    1997-04-01

    We represent the state of a circa 10-nm thick submicron dimensioned magnetic film with a superposition of two-dimensional (2D) magnetic pseudovortices. The effective intervortex exchange-stiffness potential and local magnetization angle at a complex distance z=x+iy from the kth vortex center are given by the real and imaginary parts respectively, of the function -wklnz. Each of the four corners of the rectangle has a stationary quarter vortex with negative winding (wk=-1). Two mobile semivortices with winding wk=+1 and N and S magnetic poles lie at general positions X1 and X2, respectively, along edges of the rectangle. The approximate boundary condition of vanishing M-component normal to each edge is satisfied by repeated reflections which generate a periodic extension of this vortex array to a lattice filling all of a 2D space. The internal energy V(X1,X2) is principally composed of the inter vortex exchange stiffness. Given this function, numerical evaluation of the integrated moment m=m(X1,X2) provides the functional dependence of V on m as parametrized by (X1,X2). The function V(X1,X2) has four equal minima representing states with the N and S vortices located at diagonally opposite corners, in agreement with direct numerical simulations. Therefore, the predicted hysteresis behavior of our vortex model has significantly more complex transitions than those of a uniaxial single-domain particle having only two minima. Our employment of but two variables, rather than the continuum of straightforward micromagnetics, makes possible a more insightful analysis of the smallscale structures used in storage and memory.

  20. OIL POLLUTION ABSTRACTS. VOLUME 6, NUMBER 1

    EPA Science Inventory

    Oil Pollution Abstracts (formerly entitled Oil Pollution Reports) is a quarterly compilation of abstracts of current oil pollution related literature and research projects. Comprehensive coverage of oil pollution and its prevention and control is provided, with emphasis on the aq...

  1. An algorithm for generating abstract syntax trees

    NASA Technical Reports Server (NTRS)

    Noonan, R. E.

    1985-01-01

    The notion of an abstract syntax is discussed. An algorithm is presented for automatically deriving an abstract syntax directly from a BNF grammar. The implementation of this algorithm and its application to the grammar for Modula are discussed.

  2. 2013 SYR Accepted Poster Abstracts.

    PubMed

    2013-01-01

    SYR 2013 Accepted Poster abstracts: 1. Benefits of Yoga as a Wellness Practice in a Veterans Affairs (VA) Health Care Setting: If You Build It, Will They Come? 2. Yoga-based Psychotherapy Group With Urban Youth Exposed to Trauma. 3. Embodied Health: The Effects of a Mind�Body Course for Medical Students. 4. Interoceptive Awareness and Vegetable Intake After a Yoga and Stress Management Intervention. 5. Yoga Reduces Performance Anxiety in Adolescent Musicians. 6. Designing and Implementing a Therapeutic Yoga Program for Older Women With Knee Osteoarthritis. 7. Yoga and Life Skills Eating Disorder Prevention Among 5th Grade Females: A Controlled Trial. 8. A Randomized, Controlled Trial Comparing the Impact of Yoga and Physical Education on the Emotional and Behavioral Functioning of Middle School Children. 9. Feasibility of a Multisite, Community based Randomized Study of Yoga and Wellness Education for Women With Breast Cancer Undergoing Chemotherapy. 10. A Delphi Study for the Development of Protocol Guidelines for Yoga Interventions in Mental Health. 11. Impact Investigation of Breathwalk Daily Practice: Canada�India Collaborative Study. 12. Yoga Improves Distress, Fatigue, and Insomnia in Older Veteran Cancer Survivors: Results of a Pilot Study. 13. Assessment of Kundalini Mantra and Meditation as an Adjunctive Treatment With Mental Health Consumers. 14. Kundalini Yoga Therapy Versus Cognitive Behavior Therapy for Generalized Anxiety Disorder and Co-Occurring Mood Disorder. 15. Baseline Differences in Women Versus Men Initiating Yoga Programs to Aid Smoking Cessation: Quitting in Balance Versus QuitStrong. 16. Pranayam Practice: Impact on Focus and Everyday Life of Work and Relationships. 17. Participation in a Tailored Yoga Program is Associated With Improved Physical Health in Persons With Arthritis. 18. Effects of Yoga on Blood Pressure: Systematic Review and Meta-analysis. 19. A Quasi-experimental Trial of a Yoga based Intervention to Reduce Stress and

  3. Cavity approximation for graphical models.

    PubMed

    Rizzo, T; Wemmenhove, B; Kappen, H J

    2007-07-01

    We reformulate the cavity approximation (CA), a class of algorithms recently introduced for improving the Bethe approximation estimates of marginals in graphical models. In our formulation, which allows for the treatment of multivalued variables, a further generalization to factor graphs with arbitrary order of interaction factors is explicitly carried out, and a message passing algorithm that implements the first order correction to the Bethe approximation is described. Furthermore, we investigate an implementation of the CA for pairwise interactions. In all cases considered we could confirm that CA[k] with increasing k provides a sequence of approximations of markedly increasing precision. Furthermore, in some cases we could also confirm the general expectation that the approximation of order k , whose computational complexity is O(N(k+1)) has an error that scales as 1/N(k+1) with the size of the system. We discuss the relation between this approach and some recent developments in the field. PMID:17677405

  4. Approximate circuits for increased reliability

    SciTech Connect

    Hamlet, Jason R.; Mayo, Jackson R.

    2015-08-18

    Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.

  5. Approximate circuits for increased reliability

    SciTech Connect

    Hamlet, Jason R.; Mayo, Jackson R.

    2015-12-22

    Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.

  6. Structural optimization with approximate sensitivities

    NASA Technical Reports Server (NTRS)

    Patnaik, S. N.; Hopkins, D. A.; Coroneos, R.

    1994-01-01

    Computational efficiency in structural optimization can be enhanced if the intensive computations associated with the calculation of the sensitivities, that is, gradients of the behavior constraints, are reduced. Approximation to gradients of the behavior constraints that can be generated with small amount of numerical calculations is proposed. Structural optimization with these approximate sensitivities produced correct optimum solution. Approximate gradients performed well for different nonlinear programming methods, such as the sequence of unconstrained minimization technique, method of feasible directions, sequence of quadratic programming, and sequence of linear programming. Structural optimization with approximate gradients can reduce by one third the CPU time that would otherwise be required to solve the problem with explicit closed-form gradients. The proposed gradient approximation shows potential to reduce intensive computation that has been associated with traditional structural optimization.

  7. At the HeART of Abstraction

    ERIC Educational Resources Information Center

    Berdit, Nancy

    2006-01-01

    Abstraction has long been a concept difficult to define for students. Students often feel the pressure of making their artwork "look real" and frustration can often lead to burnout in the classroom. In this article, the author describes how her lesson on abstraction has alleviated much of that pressure as students created an abstract acrylic…

  8. 37 CFR 1.438 - The abstract.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false The abstract. 1.438 Section 1... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES International Processing Provisions The International Application § 1.438 The abstract. (a) Requirements as to the content and form of the abstract are set forth...

  9. 37 CFR 1.438 - The abstract.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false The abstract. 1.438 Section 1... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES International Processing Provisions The International Application § 1.438 The abstract. (a) Requirements as to the content and form of the abstract are set forth...

  10. 37 CFR 1.438 - The abstract.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false The abstract. 1.438 Section 1... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES International Processing Provisions The International Application § 1.438 The abstract. (a) Requirements as to the content and form of the abstract are set forth...

  11. 37 CFR 1.438 - The abstract.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false The abstract. 1.438 Section 1... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES International Processing Provisions The International Application § 1.438 The abstract. (a) Requirements as to the content and form of the abstract are set forth...

  12. 37 CFR 1.438 - The abstract.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false The abstract. 1.438 Section 1... COMMERCE GENERAL RULES OF PRACTICE IN PATENT CASES International Processing Provisions The International Application § 1.438 The abstract. (a) Requirements as to the content and form of the abstract are set forth...

  13. Writing a Structured Abstract for the Thesis

    ERIC Educational Resources Information Center

    Hartley, James

    2010-01-01

    This article presents the author's suggestions on how to improve thesis abstracts. The author describes two books on writing abstracts: (1) "Creating Effective Conference Abstracts and Posters in Biomedicine: 500 tips for Success" (Fraser, Fuller & Hutber, 2009), a compendium of clear advice--a must book to have in one's hand as one prepares a…

  14. The Cosmic Background Explorer

    NASA Technical Reports Server (NTRS)

    Gulkis, Samuel; Lubin, Philip M.; Meyer, Stephan S.; Silverberg, Robert F.

    1990-01-01

    The Cosmic Background Explorer (CBE), NASA's cosmological satellite which will observe a radiative relic of the big bang, is discussed. The major questions connected to the big bang theory which may be clarified using the CBE are reviewed. The satellite instruments and experiments are described, including the Differential Microwave Radiometer, which measures the difference between microwave radiation emitted from two points on the sky, the Far-Infrared Absolute Spectrophotometer, which compares the spectrum of radiation from the sky at wavelengths from 100 microns to one cm with that from an internal blackbody, and the Diffuse Infrared Background Experiment, which searches for the radiation from the earliest generation of stars.

  15. Texture induced microwave background anisotropies

    SciTech Connect

    Borrill, Julian; Copeland, Edmund J.; Liddle, Andrew R.; Stebbins, Albert; Veeraraghavan, Shoba

    1994-03-01

    We use numerical simulations to calculate the cosmic microwave background anisotropy induced by the evolution of a global texture field, with special emphasis on individual textures. Both spherically symmetric and general configurations are analyzed, and in the latter case we consider field configurations which exhibit unwinding events and also ones which do not. We compare the results given by evolving the field numerically under both the expanded core (XCORE) and non-linear sigma model (NLSM) approximations with the analytic predictions of the NLSM exact solution for a spherically symmetric self-similar (SSSS) unwinding. We find that the random unwinding configuration spots' typical peak height is 60-75\\% and angular size typically only 10% of those of the SSSS unwinding, and that random configurations without an unwinding event nonetheless may generate indistinguishable hot and cold spots. A brief comparison is made with other work.

  16. China: Background Notes Series.

    ERIC Educational Resources Information Center

    Reams, Joanne Reppert

    Concise background information on the People's Republic of China is provided. The publication begins with a profile of the country, outlining the people, geography, economy, and membership in international organizations. The bulk of the document then discusses in more detail China's people, geography, history, government, education, economy, and…

  17. Nonthermal cosmic neutrino background

    NASA Astrophysics Data System (ADS)

    Chen, Mu-Chun; Ratz, Michael; Trautner, Andreas

    2015-12-01

    We point out that, for Dirac neutrinos, in addition to the standard thermal cosmic neutrino background (C ν B ), there could also exist a nonthermal neutrino background with comparable number density. As the right-handed components are essentially decoupled from the thermal bath of standard model particles, relic neutrinos with a nonthermal distribution may exist until today. The relic density of the nonthermal (nt) background can be constrained by the usual observational bounds on the effective number of massless degrees of freedom Neff and can be as large as nν nt≲0.5 nγ. In particular, Neff can be larger than 3.046 in the absence of any exotic states. Nonthermal relic neutrinos constitute an irreducible contribution to the detection of the C ν B and, hence, may be discovered by future experiments such as PTOLEMY. We also present a scenario of chaotic inflation in which a nonthermal background can naturally be generated by inflationary preheating. The nonthermal relic neutrinos, thus, may constitute a novel window into the very early Universe.

  18. Berkeley Low Background Facility

    NASA Astrophysics Data System (ADS)

    Thomas, K. J.; Smith, A. R.; Poon, A. W. P.; Chan, Y. D.; Norman, E. B.; Lesko, K. T.

    2015-08-01

    The Berkeley Low Background Facility (BLBF) at Lawrence Berkeley National Laboratory (LBNL) in Berkeley, California provides low background gamma spectroscopy services to a wide array of experiments and projects. The analysis of samples takes place within two unique facilities; locally within a carefully-constructed, low background laboratory on the surface at LBNL and at the Sanford Underground Research Facility (SURF) in Lead, SD. These facilities provide a variety of gamma spectroscopy services to low background experiments primarily in the form of passive material screening for primordial radioisotopes (U, Th, K) or common cosmogenic/anthropogenic products; active screening via neutron activation analysis for U,Th, and K as well as a variety of stable isotopes; and neutron flux/beam characterization measurements through the use of monitors. A general overview of the facilities, services, and sensitivities will be presented. Recent activities and upgrades will also be described including an overview of the recently installed counting system at SURF (recently relocated from Oroville, CA in 2014), the installation of a second underground counting station at SURF in 2015, and future plans. The BLBF is open to any users for counting services or collaboration on a wide variety of experiments and projects.

  19. Berkeley Low Background Facility

    SciTech Connect

    Thomas, K. J.; Norman, E. B.; Smith, A. R.; Poon, A. W. P.; Chan, Y. D.; Lesko, K. T.

    2015-08-17

    The Berkeley Low Background Facility (BLBF) at Lawrence Berkeley National Laboratory (LBNL) in Berkeley, California provides low background gamma spectroscopy services to a wide array of experiments and projects. The analysis of samples takes place within two unique facilities; locally within a carefully-constructed, low background laboratory on the surface at LBNL and at the Sanford Underground Research Facility (SURF) in Lead, SD. These facilities provide a variety of gamma spectroscopy services to low background experiments primarily in the form of passive material screening for primordial radioisotopes (U, Th, K) or common cosmogenic/anthropogenic products; active screening via neutron activation analysis for U,Th, and K as well as a variety of stable isotopes; and neutron flux/beam characterization measurements through the use of monitors. A general overview of the facilities, services, and sensitivities will be presented. Recent activities and upgrades will also be described including an overview of the recently installed counting system at SURF (recently relocated from Oroville, CA in 2014), the installation of a second underground counting station at SURF in 2015, and future plans. The BLBF is open to any users for counting services or collaboration on a wide variety of experiments and projects.

  20. Foregrounding the Background.

    ERIC Educational Resources Information Center

    Robbins, Bruce

    1998-01-01

    Argues that when introductory activities to the classics begin with background information, it can upstage or confine the life of the story, and shows little faith in the students as readers or in the literature itself. Suggests sometimes letting the literature begin, and then helping students make sense of it. Discusses examples from "To Kill a…

  1. Monitored background radiometer

    NASA Technical Reports Server (NTRS)

    Ruel, C.; Larouche, M.; Donato, M.

    1986-01-01

    The infrared (IR) testing of the Olympus thermal model has provided a capability to perform cost effective thermal balance testing of satellites and satellite components. A high-accuracy monitored background radiometer was developed for the measurement of absorbed radiation heat flux encountered during IR thermal vacuum testing of spacecraft. The design, development, and calibration of this radiometer is described.

  2. Research & writing basics: elements of the abstract.

    PubMed

    Krasner, D; Van Rijswijk, L

    1995-04-01

    Writing an abstract is a challenging skill that requires precision and care. Criteria for well-formulated abstracts and abstract guidelines for 2 types of articles (empirical studies and reviews or theoretical articles) as well as a description of the content of a structured abstract are presented. Details were gleaned from a review of the literature including the American Medical Association Manual of Style, Eighth Edition and the Publication Manual of the American Psychological Association, Fourth Edition. A good abstract is like a crystal: it is a clear, sharp synthesis that elucidates meaning for the reader. PMID:7546111

  3. Coupling Radar Rainfall to Hydrological Models for Water Abstraction Management

    NASA Astrophysics Data System (ADS)

    Asfaw, Alemayehu; Shucksmith, James; Smith, Andrea; MacDonald, Ken

    2015-04-01

    propagated through the model to assess its influence on the forecasted flow uncertainty. Furthermore, the effects of uncertainties at different forecast lead times on potential abstraction strategies are assessed. The results show that over a 10 year period, an average of approximately 70 ML/d of potential water is missed in the study catchment under a convention abstraction regime. This indicates a considerable potential for the use of flow forecasting models to effectively implement advanced abstraction management and more efficiently utilize available water resources in the study catchment.

  4. Why We Need a Structured Abstract in Education Research

    ERIC Educational Resources Information Center

    Mosteller, Frederick; Nave, Bill; Miech, Edward J.

    2004-01-01

    Background: Approximately 1,100 education journals collectively publish more than 20,000 education research articles each year. Under current practice, no systematic way exists to move the research findings from these studies into the hands of the millions of education practitioners and policymakers in the United States who might use them.…

  5. Holographic thermalization in a quark confining background

    SciTech Connect

    Ageev, D. S. Aref’eva, I. Ya.

    2015-03-15

    We study holographic thermalization of a strongly coupled theory inspired by two colliding shock waves in a vacuum confining background. Holographic thermalization means a black hole formation, in fact, a trapped surface formation. As the vacuum confining background, we considered the well-know bottom-up AdS/QCD model that provides the Cornell potential and reproduces the QCD β-function. We perturb the vacuum background by colliding domain shock waves that are assumed to be holographically dual to heavy ions collisions. Our main physical assumption is that we can make a restriction on the time of trapped surface formation, which results in a natural limitation on the size of the domain where the trapped surface is produced. This limits the intermediate domain where the main part of the entropy is produced. In this domain, we can use an intermediate vacuum background as an approximation to the full confining background. We find that the dependence of the multiplicity on energy for the intermediate background has an asymptotic expansion whose first term depends on energy as E{sup 1/3}, which is very similar to the experimental dependence of particle multiplicities on the colliding ion energy obtained from the RHIC and LHC. However, this first term, at the energies where the approximation of the confining metric by the intermediate background works, does not saturate the exact answer, and we have to take the nonleading terms into account.

  6. Selected Abstracts from ERIC. Resources in Vocational Education. Volume 14, Number 5, 1981-1982.

    ERIC Educational Resources Information Center

    Resources in Vocational Education, 1981

    1981-01-01

    This issue contains approximately 250 abstracts selected from the ERIC Clearinghouse on Adult, Career, and Vocational Education related to vocational and technical education research and development from the June through November 1980 Resources in Education. Abstracts, ordered by ED number, may include some or all of the following information:…

  7. Mathematical algorithms for approximate reasoning

    NASA Technical Reports Server (NTRS)

    Murphy, John H.; Chay, Seung C.; Downs, Mary M.

    1988-01-01

    Most state of the art expert system environments contain a single and often ad hoc strategy for approximate reasoning. Some environments provide facilities to program the approximate reasoning algorithms. However, the next generation of expert systems should have an environment which contain a choice of several mathematical algorithms for approximate reasoning. To meet the need for validatable and verifiable coding, the expert system environment must no longer depend upon ad hoc reasoning techniques but instead must include mathematically rigorous techniques for approximate reasoning. Popular approximate reasoning techniques are reviewed, including: certainty factors, belief measures, Bayesian probabilities, fuzzy logic, and Shafer-Dempster techniques for reasoning. A group of mathematically rigorous algorithms for approximate reasoning are focused on that could form the basis of a next generation expert system environment. These algorithms are based upon the axioms of set theory and probability theory. To separate these algorithms for approximate reasoning various conditions of mutual exclusivity and independence are imposed upon the assertions. Approximate reasoning algorithms presented include: reasoning with statistically independent assertions, reasoning with mutually exclusive assertions, reasoning with assertions that exhibit minimum overlay within the state space, reasoning with assertions that exhibit maximum overlay within the state space (i.e. fuzzy logic), pessimistic reasoning (i.e. worst case analysis), optimistic reasoning (i.e. best case analysis), and reasoning with assertions with absolutely no knowledge of the possible dependency among the assertions. A robust environment for expert system construction should include the two modes of inference: modus ponens and modus tollens. Modus ponens inference is based upon reasoning towards the conclusion in a statement of logical implication, whereas modus tollens inference is based upon reasoning away

  8. Exponential approximations in optimal design

    NASA Technical Reports Server (NTRS)

    Belegundu, A. D.; Rajan, S. D.; Rajgopal, J.

    1990-01-01

    One-point and two-point exponential functions have been developed and proved to be very effective approximations of structural response. The exponential has been compared to the linear, reciprocal and quadratic fit methods. Four test problems in structural analysis have been selected. The use of such approximations is attractive in structural optimization to reduce the numbers of exact analyses which involve computationally expensive finite element analysis.

  9. Approximate factorization with source terms

    NASA Technical Reports Server (NTRS)

    Shih, T. I.-P.; Chyu, W. J.

    1991-01-01

    A comparative evaluation is made of three methodologies with a view to that which offers the best approximate factorization error. While two of these methods are found to lead to more efficient algorithms in cases where factors which do not contain source terms can be diagonalized, the third method used generates the lowest approximate factorization error. This method may be preferred when the norms of source terms are large, and transient solutions are of interest.

  10. Background illumination simulator

    SciTech Connect

    Towry, E.R.

    1992-05-12

    This patent describes a testing apparatus for testing and evaluating the performance of laser seeking warheads for missiles, under simulated weather conditions. It comprises support means for supporting a warhead seeker; laser means for generating a laser beam and for directing a laser beam towards the seeker; a diffusion screen interposed between the seeker support means and the laser means for diffusing the laser beam; a collimating lens interposed between the diffusion screen and the seeker support means for collimating the diffused laser beam and for directing the collimated laser beam onto a warhead seeker, supported in the seeker support; background illuminator means for illuminating the seeker support and a seeker disposed therein, supported for movement into and out of an operating position between the diffusion means and the collimating lens for providing background lighting in simulation of weather lighting conditions; and control means for controlling the intensity of the light provided by the illuminator means to simulate various weather conditions.

  11. Approximating random quantum optimization problems

    NASA Astrophysics Data System (ADS)

    Hsu, B.; Laumann, C. R.; Läuchli, A. M.; Moessner, R.; Sondhi, S. L.

    2013-06-01

    We report a cluster of results regarding the difficulty of finding approximate ground states to typical instances of the quantum satisfiability problem k-body quantum satisfiability (k-QSAT) on large random graphs. As an approximation strategy, we optimize the solution space over “classical” product states, which in turn introduces a novel autonomous classical optimization problem, PSAT, over a space of continuous degrees of freedom rather than discrete bits. Our central results are (i) the derivation of a set of bounds and approximations in various limits of the problem, several of which we believe may be amenable to a rigorous treatment; (ii) a demonstration that an approximation based on a greedy algorithm borrowed from the study of frustrated magnetism performs well over a wide range in parameter space, and its performance reflects the structure of the solution space of random k-QSAT. Simulated annealing exhibits metastability in similar “hard” regions of parameter space; and (iii) a generalization of belief propagation algorithms introduced for classical problems to the case of continuous spins. This yields both approximate solutions, as well as insights into the free energy “landscape” of the approximation problem, including a so-called dynamical transition near the satisfiability threshold. Taken together, these results allow us to elucidate the phase diagram of random k-QSAT in a two-dimensional energy-density-clause-density space.

  12. Some background about satellites

    NASA Technical Reports Server (NTRS)

    Burns, Joseph A.

    1986-01-01

    Four tables of planetary and satellite data are presented which list satellite discoveries, planetary parameters, satellite orbits, and satellite physical properties respectively. A scheme for classifying the satellites is provided and it is noted that most known moons fall into three general classes: regular satellites, collisional shards, and irregular satellites. Satellite processes are outlined with attention given to origins, dynamical and thermal evolution, surface processes, and composition and cratering. Background material is provided for each family of satellites.

  13. A Shallow Underground Laboratory for Low-Background Radiation Measurements and Materials Development

    SciTech Connect

    Aalseth, Craig E.; Bonicalzi, Ricco; Cantaloub, Michael G.; Day, Anthony R.; Erikson, Luke E.; Fast, James E.; Forrester, Joel B.; Fuller, Erin S.; Glasgow, Brian D.; Greenwood, Lawrence R.; Hoppe, Eric W.; Hossbach, Todd W.; Hyronimus, Brian J.; Keillor, Martin E.; Mace, Emily K.; McIntyre, Justin I.; Merriman, Jason H.; Myers, Allan W.; Overman, Cory T.; Overman, Nicole R.; Panisko, Mark E.; Seifert, Allen; Warren, Glen A.; Runkle, Robert C.

    2012-11-08

    Abstract: Pacific Northwest National Laboratory recently commissioned a new shallow underground laboratory, located at a depth of approximately 30 meters water-equivalent. This new addition to the small class of radiation measurement laboratories located at modest underground depths worldwide houses the latest generation of custom-made, high-efficiency, low-background gamma-ray spectrometers and gas proportional counters. This manuscript describes the unique capabilities present in the shallow underground laboratory; these include large-scale ultra-pure materials production and a suite of radiation detection systems. Reported data characterize the degree of background reduction achieved through a combination of underground location, graded shielding, and rejection of cosmic-ray events. We conclude by presenting measurement targets and future opportunities.

  14. Wavelet Sparse Approximate Inverse Preconditioners

    NASA Technical Reports Server (NTRS)

    Chan, Tony F.; Tang, W.-P.; Wan, W. L.

    1996-01-01

    There is an increasing interest in using sparse approximate inverses as preconditioners for Krylov subspace iterative methods. Recent studies of Grote and Huckle and Chow and Saad also show that sparse approximate inverse preconditioner can be effective for a variety of matrices, e.g. Harwell-Boeing collections. Nonetheless a drawback is that it requires rapid decay of the inverse entries so that sparse approximate inverse is possible. However, for the class of matrices that, come from elliptic PDE problems, this assumption may not necessarily hold. Our main idea is to look for a basis, other than the standard one, such that a sparse representation of the inverse is feasible. A crucial observation is that the kind of matrices we are interested in typically have a piecewise smooth inverse. We exploit this fact, by applying wavelet techniques to construct a better sparse approximate inverse in the wavelet basis. We shall justify theoretically and numerically that our approach is effective for matrices with smooth inverse. We emphasize that in this paper we have only presented the idea of wavelet approximate inverses and demonstrated its potential but have not yet developed a highly refined and efficient algorithm.

  15. Approximate entropy of network parameters.

    PubMed

    West, James; Lacasa, Lucas; Severini, Simone; Teschendorff, Andrew

    2012-04-01

    We study the notion of approximate entropy within the framework of network theory. Approximate entropy is an uncertainty measure originally proposed in the context of dynamical systems and time series. We first define a purely structural entropy obtained by computing the approximate entropy of the so-called slide sequence. This is a surrogate of the degree sequence and it is suggested by the frequency partition of a graph. We examine this quantity for standard scale-free and Erdös-Rényi networks. By using classical results of Pincus, we show that our entropy measure often converges with network size to a certain binary Shannon entropy. As a second step, with specific attention to networks generated by dynamical processes, we investigate approximate entropy of horizontal visibility graphs. Visibility graphs allow us to naturally associate with a network the notion of temporal correlations, therefore providing the measure a dynamical garment. We show that approximate entropy distinguishes visibility graphs generated by processes with different complexity. The result probes to a greater extent these networks for the study of dynamical systems. Applications to certain biological data arising in cancer genomics are finally considered in the light of both approaches. PMID:22680542

  16. Approximate entropy of network parameters

    NASA Astrophysics Data System (ADS)

    West, James; Lacasa, Lucas; Severini, Simone; Teschendorff, Andrew

    2012-04-01

    We study the notion of approximate entropy within the framework of network theory. Approximate entropy is an uncertainty measure originally proposed in the context of dynamical systems and time series. We first define a purely structural entropy obtained by computing the approximate entropy of the so-called slide sequence. This is a surrogate of the degree sequence and it is suggested by the frequency partition of a graph. We examine this quantity for standard scale-free and Erdös-Rényi networks. By using classical results of Pincus, we show that our entropy measure often converges with network size to a certain binary Shannon entropy. As a second step, with specific attention to networks generated by dynamical processes, we investigate approximate entropy of horizontal visibility graphs. Visibility graphs allow us to naturally associate with a network the notion of temporal correlations, therefore providing the measure a dynamical garment. We show that approximate entropy distinguishes visibility graphs generated by processes with different complexity. The result probes to a greater extent these networks for the study of dynamical systems. Applications to certain biological data arising in cancer genomics are finally considered in the light of both approaches.

  17. Relativistic regular approximations revisited: An infinite-order relativistic approximation

    SciTech Connect

    Dyall, K.G.; van Lenthe, E.

    1999-07-01

    The concept of the regular approximation is presented as the neglect of the energy dependence of the exact Foldy{endash}Wouthuysen transformation of the Dirac Hamiltonian. Expansion of the normalization terms leads immediately to the zeroth-order regular approximation (ZORA) and first-order regular approximation (FORA) Hamiltonians as the zeroth- and first-order terms of the expansion. The expansion may be taken to infinite order by using an un-normalized Foldy{endash}Wouthuysen transformation, which results in the ZORA Hamiltonian and a nonunit metric. This infinite-order regular approximation, IORA, has eigenvalues which differ from the Dirac eigenvalues by order E{sup 3}/c{sup 4} for a hydrogen-like system, which is a considerable improvement over the ZORA eigenvalues, and similar to the nonvariational FORA energies. A further perturbation analysis yields a third-order correction to the IORA energies, TIORA. Results are presented for several systems including the neutral U atom. The IORA eigenvalues for all but the 1s spinor of the neutral system are superior even to the scaled ZORA energies, which are exact for the hydrogenic system. The third-order correction reduces the IORA error for the inner orbitals to a very small fraction of the Dirac eigenvalue. {copyright} {ital 1999 American Institute of Physics.}

  18. Analysis of complex networks using aggressive abstraction.

    SciTech Connect

    Colbaugh, Richard; Glass, Kristin.; Willard, Gerald

    2008-10-01

    This paper presents a new methodology for analyzing complex networks in which the network of interest is first abstracted to a much simpler (but equivalent) representation, the required analysis is performed using the abstraction, and analytic conclusions are then mapped back to the original network and interpreted there. We begin by identifying a broad and important class of complex networks which admit abstractions that are simultaneously dramatically simplifying and property preserving - we call these aggressive abstractions -- and which can therefore be analyzed using the proposed approach. We then introduce and develop two forms of aggressive abstraction: 1.) finite state abstraction, in which dynamical networks with uncountable state spaces are modeled using finite state systems, and 2.) onedimensional abstraction, whereby high dimensional network dynamics are captured in a meaningful way using a single scalar variable. In each case, the property preserving nature of the abstraction process is rigorously established and efficient algorithms are presented for computing the abstraction. The considerable potential of the proposed approach to complex networks analysis is illustrated through case studies involving vulnerability analysis of technological networks and predictive analysis for social processes.

  19. Neurobiological background of negative symptoms.

    PubMed

    Galderisi, Silvana; Merlotti, Eleonora; Mucci, Armida

    2015-10-01

    Studies investigating neurobiological bases of negative symptoms of schizophrenia failed to provide consistent findings, possibly due to the heterogeneity of this psychopathological construct. We tried to review the findings published to date investigating neurobiological abnormalities after reducing the heterogeneity of the negative symptoms construct. The literature in electronic databases as well as citations and major articles are reviewed with respect to the phenomenology, pathology, genetics and neurobiology of schizophrenia. We searched PubMed with the keywords "negative symptoms," "deficit schizophrenia," "persistent negative symptoms," "neurotransmissions," "neuroimaging" and "genetic." Additional articles were identified by manually checking the reference lists of the relevant publications. Publications in English were considered, and unpublished studies, conference abstracts and poster presentations were not included. Structural and functional imaging studies addressed the issue of neurobiological background of negative symptoms from several perspectives (considering them as a unitary construct, focusing on primary and/or persistent negative symptoms and, more recently, clustering them into factors), but produced discrepant findings. The examined studies provided evidence suggesting that even primary and persistent negative symptoms include different psychopathological constructs, probably reflecting the dysfunction of different neurobiological substrates. Furthermore, they suggest that complex alterations in multiple neurotransmitter systems and genetic variants might influence the expression of negative symptoms in schizophrenia. On the whole, the reviewed findings, representing the distillation of a large body of disparate data, suggest that further deconstruction of negative symptomatology into more elementary components is needed to gain insight into underlying neurobiological mechanisms. PMID:25797499

  20. Prefrontal cortex organization: dissociating effects of temporal abstraction, relational abstraction, and integration with FMRI.

    PubMed

    Nee, Derek Evan; Jahn, Andrew; Brown, Joshua W

    2014-09-01

    The functions of the prefrontal cortex (PFC) underlie higher-level cognition. Varying proposals suggest that the PFC is organized along a rostral-caudal gradient of abstraction with more abstract representations/processes associated with more rostral areas. However, the operational definition of abstraction is unclear. Here, we contrasted 2 prominent theories of abstraction--temporal and relational--using fMRI. We further examined whether integrating abstract rules--a function common to each theory--recruited the PFC independently of other abstraction effects. While robust effects of relational abstraction were present in the PFC, temporal abstraction effects were absent. Instead, we found activations specific to the integration of relational rules in areas previously shown to be associated with temporal abstraction. We suggest that previous effects of temporal abstraction were due to confounds with integration demands. We propose an integration framework to understand the functions of the PFC that resolves discrepancies in prior data. PMID:23563962

  1. Gadgets, approximation, and linear programming

    SciTech Connect

    Trevisan, L.; Sudan, M.; Sorkin, G.B.; Williamson, D.P.

    1996-12-31

    We present a linear-programming based method for finding {open_quotes}gadgets{close_quotes}, i.e., combinatorial structures reducing constraints of one optimization problems to constraints of another. A key step in this method is a simple observation which limits the search space to a finite one. Using this new method we present a number of new, computer-constructed gadgets for several different reductions. This method also answers a question posed by on how to prove the optimality of gadgets-we show how LP duality gives such proofs. The new gadgets improve hardness results for MAX CUT and MAX DICUT, showing that approximating these problems to within factors of 60/61 and 44/45 respectively is N P-hard. We also use the gadgets to obtain an improved approximation algorithm for MAX 3SAT which guarantees an approximation ratio of .801. This improves upon the previous best bound of .7704.

  2. The Backgrounds Data Center

    NASA Technical Reports Server (NTRS)

    Snyder, W. A.; Gursky, H.; Heckathorn, H. M.; Lucke, R. L.; Berg, S. L.; Dombrowski, E. G.; Kessel, R. A.

    1993-01-01

    The Strategic Defense Initiative Organization has created data centers for midcourse, plumes, and backgrounds phenomenologies. The Backgrounds Data Center (BDC) has been designated as the prime archive for data collected by SDIO programs. The BDC maintains a Summary Catalog that contains 'metadata,' that is, information about data, such as when the data were obtained, what the spectral range of the data is, and what region of the Earth or sky was observed. Queries to this catalog result in a listing of all data sets (from all experiments in the Summary Catalog) that satisfy the specified criteria. Thus, the user can identify different experiments that made similar observations and order them from the BDC for analysis. On-site users can use the Science Analysis Facility (SAFE for this purpose. For some programs, the BDC maintains a Program Catalog, which can classify data in as many ways as desired (rather than just by position, time, and spectral range as in the Summary Catalog). For example, data sets could be tagged with such diverse parameters as solar illumination angle, signal level, or the value of a particular spectral ratio, as long as these quantities can be read from the digital record or calculated from it by the ingest program. All unclassified catalogs and unclassified data will be remotely accessible.

  3. Backgrounds Data Center

    NASA Astrophysics Data System (ADS)

    Snyder, William A.; Gursky, Herbert; Heckathorn, Harry M.; Lucke, Bob L.; Dorland, Bryan N.; Kessel, R. A.; Berg, S. L.; Dombrowski, E. G.

    1994-09-01

    The Backgrounds Data Center (BDC) is the designated archive for backgrounds data collected by Ballistic Missile Defense Organization (BMDO) programs, some of which include ultraviolet sensors. Currently, the BDC holds ultraviolet data from the IBSS, UVPI, UVLIM, and FUVCAM sensors. The BDC will also be the prime archive for Midcourse Space Experiment (MSX) data and is prepared to negotiate with program managers to handle other datasets. The purpose of the BDC is to make data accessible to users and to assist them in analyzing it. The BDC maintains the Science Catalog Information Exchange System (SCIES) allowing remote users to log in, read or post notices about current programs, search the catalogs for datasets of interest, and submit orders for data. On-site facilities are also available for the analysis of data, and consist of VMS and UNIX workstations with access to software analysis packages such as IDL, IRAF, and Khoros. Either on-site or remotely, users can employ the BDC-developed graphical user interface called the Visual Interface for Space and Terrestrial Analysis (VISTA) to generate catalog queries and to display and analyze data. SCIES and VISTA permit nearly complete access to BDC services and capabilities without the need to be physically present at the data center.

  4. Heat pipe transient response approximation

    NASA Astrophysics Data System (ADS)

    Reid, Robert S.

    2002-01-01

    A simple and concise routine that approximates the response of an alkali metal heat pipe to changes in evaporator heat transfer rate is described. This analytically based routine is compared with data from a cylindrical heat pipe with a crescent-annular wick that undergoes gradual (quasi-steady) transitions through the viscous and condenser boundary heat transfer limits. The sonic heat transfer limit can also be incorporated into this routine for heat pipes with more closely coupled condensers. The advantages and obvious limitations of this approach are discussed. For reference, a source code listing for the approximation appears at the end of this paper. .

  5. COGNITIVE GAINS IN "DEPRIVED" CHILDREN THROUGH INDIVIDUAL TEACHING OF LANGUAGE FOR ABSTRACT THINKING.

    ERIC Educational Resources Information Center

    BLANK, MARION

    THE MOST DISABLING HANDICAP OF YOUNG CHILDREN FROM DEPRIVED SOCIOECONOMIC BACKGROUNDS IS THEIR DIFFICULTY IN USING LANGUAGE ABSTRACTLY. IN THIS STUDY, THEREFORE, IT WAS HYPOTHESIZED THAT IF AN EDUCATIONAL INTERVENTION PROGRAM WAS LIMITED TO THE DEVELOPMENT OF ABSTRACT LANGUAGE, THEN NOT ONLY LANGUAGE, BUT MANY OTHER ASPECTS OF THINKING WOULD BE…

  6. Developing Creativity and Abstraction in Representing Data

    ERIC Educational Resources Information Center

    South, Andy

    2012-01-01

    Creating charts and graphs is all about visual abstraction: the process of representing aspects of data with imagery that can be interpreted by the reader. Children may need help making the link between the "real" and the image. This abstraction can be achieved using symbols, size, colour and position. Where the representation is close to what…

  7. Content Differences for Abstract and Concrete Concepts

    ERIC Educational Resources Information Center

    Wiemer-Hastings, Katja Katja; Xu, Xu

    2005-01-01

    Concept properties are an integral part of theories of conceptual representation and processing. To date, little is known about conceptual properties of abstract concepts, such as idea. This experiment systematically compared the content of 18 abstract and 18 concrete concepts, using a feature generation task. Thirty-one participants listed…

  8. Annual Abstract Series of Educational Material.

    ERIC Educational Resources Information Center

    Shelesnyak, M. C., Ed.

    1980-01-01

    This is the fifth annual collection of abstracts of educational materials presented by the Educational Materials Review Board of the American Physiological Society under the direction of the Education Committee. The collection includes abstracts of articles, papers, textbooks, books, handbooks, and symposia which are valuable in teaching…

  9. Abstracting in the Context of Spontaneous Learning

    ERIC Educational Resources Information Center

    Williams, Gaye

    2007-01-01

    There is evidence that spontaneous learning leads to relational understanding and high positive affect. To study spontaneous abstracting, a model was constructed by combining the RBC model of abstraction with Krutetskii's mental activities. Using video-stimulated interviews, the model was then used to analyze the behavior of two Year 8 students…

  10. National Workplace Literacy Program. 1993 Abstracts.

    ERIC Educational Resources Information Center

    Office of Vocational and Adult Education (ED), Washington, DC. National Workplace Literacy Program.

    This publication presents the abstracts of the 57 National Workplace Literacy Program 1993 projects. Each abstract provides the following information: project title; award number; project director; awardee; address; telephone and fax numbers; funds by fiscal year (federal and nonfederal); award period; federal project officer; objectives;…

  11. A Hybrid Method for Abstracting Newspaper Articles.

    ERIC Educational Resources Information Center

    Liu, James; Wu, Yan; Zhou, Lina

    1999-01-01

    Introduces a hybrid method for abstracting Chinese text that integrates the statistical approach with language understandings, incorporating some linguistics heuristics and segmentation into the abstracting process. Initial responses from application to Chinese newspaper articles show that the method contributes much to the flexibility and…

  12. Abstractions of Awareness: Aware of What?

    NASA Astrophysics Data System (ADS)

    Metaxas, Georgios; Markopoulos, Panos

    This chapter presents FN-AAR, an abstract model of awareness systems. The purpose of the model is to capture in a concise and abstract form essential aspects of awareness systems, many of which have been discussed in design essays or in the context of evaluating specific design solutions.

  13. Foundations of the Bandera Abstraction Tools

    NASA Technical Reports Server (NTRS)

    Hatcliff, John; Dwyer, Matthew B.; Pasareanu, Corina S.; Robby

    2003-01-01

    Current research is demonstrating that model-checking and other forms of automated finite-state verification can be effective for checking properties of software systems. Due to the exponential costs associated with model-checking, multiple forms of abstraction are often necessary to obtain system models that are tractable for automated checking. The Bandera Tool Set provides multiple forms of automated support for compiling concurrent Java software systems to models that can be supplied to several different model-checking tools. In this paper, we describe the foundations of Bandera's data abstraction mechanism which is used to reduce the cardinality (and the program's state-space) of data domains in software to be model-checked. From a technical standpoint, the form of data abstraction used in Bandera is simple, and it is based on classical presentations of abstract interpretation. We describe the mechanisms that Bandera provides for declaring abstractions, for attaching abstractions to programs, and for generating abstracted programs and properties. The contributions of this work are the design and implementation of various forms of tool support required for effective application of data abstraction to software components written in a programming language like Java which has a rich set of linguistic features.

  14. New Features in the ADS Abstract Service

    NASA Technical Reports Server (NTRS)

    Eichhorn, Guenther; Accomazzi, Alberto; Grant, Carolyn S.; Kurtz, Michael J.; Henneken, Edwin A.; Thompson, Donna M.; Murray, Stephen S.

    2005-01-01

    The NASA-ADS Abstract Service provides a sophisticated search capability for the literature in Astronomy, Planetary Sciences, Physics/Geophysics, and Space Instrumentation. The ADS is funded by NASA and access to the ADS services is free to anybody world-wide without restrictions. It allows the user to search the literature by author, title, and abstract text.

  15. Interpreting Abstract Interpretations in Membership Equational Logic

    NASA Technical Reports Server (NTRS)

    Fischer, Bernd; Rosu, Grigore

    2001-01-01

    We present a logical framework in which abstract interpretations can be naturally specified and then verified. Our approach is based on membership equational logic which extends equational logics by membership axioms, asserting that a term has a certain sort. We represent an abstract interpretation as a membership equational logic specification, usually as an overloaded order-sorted signature with membership axioms. It turns out that, for any term, its least sort over this specification corresponds to its most concrete abstract value. Maude implements membership equational logic and provides mechanisms to calculate the least sort of a term efficiently. We first show how Maude can be used to get prototyping of abstract interpretations "for free." Building on the meta-logic facilities of Maude, we further develop a tool that automatically checks and abstract interpretation against a set of user-defined properties. This can be used to select an appropriate abstract interpretation, to characterize the specified loss of information during abstraction, and to compare different abstractions with each other.

  16. Tour the Galaxy of the Abstract.

    ERIC Educational Resources Information Center

    Kennedy, Patricia

    2003-01-01

    Describes an abstract art unit in which students in an introductory art course created abstract art inspired by the work of M. C. Escher. Explains that some students are unsure of their drawing ability. States this unit helps them overcome their fears. (CMK)

  17. Some Call It Stone: Teaching Abstract Sculpture

    ERIC Educational Resources Information Center

    Asher, Rikki

    2004-01-01

    Abstract visual art is not for everybody. Some people find it threatening, uncomfortable, and often, inaccessible. Understandably, this can result in a lack of attention paid to nonrepresentational works of art in the visual arts curriculum. This article describes an experiential, hands-on, field trip that sought to demystify abstract sculpture,…

  18. Third LDEF Post-Retrieval Symposium Abstracts

    NASA Technical Reports Server (NTRS)

    Levine, Arlene S. (Compiler)

    1993-01-01

    This volume is a compilation of abstracts submitted to the Third Long Duration Exposure Facility (LDEF) Post-Retrieval Symposium. The abstracts represent the data analysis of the 57 experiments flown on the LDEF. The experiments include materials, coatings, thermal systems, power and propulsion, science (cosmic ray, interstellar gas, heavy ions, micrometeoroid, etc.), electronics, optics, and life science.

  19. Romanian Scientific Abstracts, Volume 10 Number 3.

    ERIC Educational Resources Information Center

    Caracas, Angela, Ed.

    The material included in the monthly issues of the "Romanian Scientific Abstracts" as bibliographic references or abstracts is arranged according to discipline and main numerical sequence. The December issue includes a subject index for the material included throughout the year. It also indicates, in an appended table, the numerical symbol of…

  20. Romanian Scientific Abstracts, Volume 10 Number 1.

    ERIC Educational Resources Information Center

    Caracas, Angela, Ed.

    The material included in the monthly issues of the "Romanian Scientific Abstracts" as bibliographic references or abstracts is arranged according to discipline and main problems and is provided with an index and with key-words. The entries are recorded in numerical sequence. The December issue includes a subject index for the material included…

  1. Romanian Scientific Abstracts, Volume 10 Number 6.

    ERIC Educational Resources Information Center

    Caracas, Angela, Ed.

    The material included in the monthly issues of the "Romanian Scientific Abstracts" as bibliographic references or abstracts is arranged according to discipline and main problems and is provided with an index and with key-words. The entries are recorded in numerical sequence. The December issue includes a subject index for the material included…

  2. Romanian Scientific Abstracts, Volume 10 Number 4.

    ERIC Educational Resources Information Center

    Caracas, Angela, Ed.

    The material included in the monthly issues of the "Romanian Scientific Abstracts" as bibliographic references or abstracts is arranged according to discipline and main problems and is provided with an index and with key-words. The entries are recorded in numeric sequence. The December issue includes a subject index for the material included…

  3. Romanian Scientific Abstracts, Volume 10 Number 5.

    ERIC Educational Resources Information Center

    Caracas, Angela, Ed.

    The material included in the monthly issues of the "Romanian Scientific Abstracts" as bibliographic references or abstracts is arranged according to discipline and main problems and is provided with an index and with key-words. The entries are recorded in numeric sequence. The December issue includes a subject index for the material included…

  4. Romanian Scientific Abstracts, Volume 9 Number 11.

    ERIC Educational Resources Information Center

    Caracas, Angela, Ed.

    The material included in the monthly issues of the "Romanian Scientific Abstracts" as bibliographic references or abstracts is arranged according to discipline and main problems and is provided with an index and with key-words. The entries are recorded in numerical sequence. The December issue includes a subject index for the material included…

  5. Romanian Scientific Abstracts, Volume 9 Number 12.

    ERIC Educational Resources Information Center

    Caracas, Angela, Ed.

    The material included in the monthly issues of the "Romanian Scientific Abstracts" as bibliographic references or abstracts is arranged according to discipline and main problems and is provided with an index and with key-words. T8e entries are recorded in numerical sequence. The December issue includes a subject index for the material included…

  6. Romanian Scientific Abstracts, Volume 10 Number 2.

    ERIC Educational Resources Information Center

    Caracas, Angela, Ed.

    The material included in the monthly issues of the "Romanian Scientific Abstracts" as bibliographic references or abstracts is arranged according to discipline and main problems and is provided with an index and with key-words. T entries are recorded in numerical sequence. The December issue includes a subject index for the material included…

  7. Youth Studies Abstracts. Vol. 4 No. 1.

    ERIC Educational Resources Information Center

    Youth Studies Abstracts, 1985

    1985-01-01

    This volume contains abstracts of 76 projects (most of which were conducted in Australia and New Zealand) concerned with programs for youth and with social and educational developments affecting youth. The abstracts are arranged in the following two categories: (1) Social and Educational Developments: Policy, Analysis, Research; and (2) Programs:…

  8. Interactional Metadiscourse in Research Article Abstracts

    ERIC Educational Resources Information Center

    Gillaerts, Paul; Van de Velde, Freek

    2010-01-01

    This paper deals with interpersonality in research article abstracts analysed in terms of interactional metadiscourse. The evolution in the distribution of three prominent interactional markers comprised in Hyland's (2005a) model, viz. hedges, boosters and attitude markers, is investigated in three decades of abstract writing in the field of…

  9. Writing Abstracts for Free-Text Searching.

    ERIC Educational Resources Information Center

    Fidel, Raya

    1986-01-01

    This study surveyed abstracting policies and guidelines used by producers of bibliographic databases that aim to enhance free-text retrieval. Results indicate editors consider content of abstracts and their language as primary factors in retrieval enhancement. Most recommend that concepts and form be coordinated with controlled vocabulary…

  10. A Microfilm Index to "Chemical Abstracts"

    ERIC Educational Resources Information Center

    Robinson, F.

    1973-01-01

    To improve access to the recent Chemical Abstracts,'' a cumulative quarterly index, based on the keyword phrases, has been produced in microfilm form. The index is available soon after the end of each quarter. Abstract titles are included in the index, thus increasing its value as a working tool. (4 references) (Author/SJ)

  11. Pythagorean Approximations and Continued Fractions

    ERIC Educational Resources Information Center

    Peralta, Javier

    2008-01-01

    In this article, we will show that the Pythagorean approximations of [the square root of] 2 coincide with those achieved in the 16th century by means of continued fractions. Assuming this fact and the known relation that connects the Fibonacci sequence with the golden section, we shall establish a procedure to obtain sequences of rational numbers…

  12. Chemical Laws, Idealization and Approximation

    NASA Astrophysics Data System (ADS)

    Tobin, Emma

    2013-07-01

    This paper examines the notion of laws in chemistry. Vihalemm ( Found Chem 5(1):7-22, 2003) argues that the laws of chemistry are fundamentally the same as the laws of physics they are all ceteris paribus laws which are true "in ideal conditions". In contrast, Scerri (2000) contends that the laws of chemistry are fundamentally different to the laws of physics, because they involve approximations. Christie ( Stud Hist Philos Sci 25:613-629, 1994) and Christie and Christie ( Of minds and molecules. Oxford University Press, New York, pp. 34-50, 2000) agree that the laws of chemistry are operationally different to the laws of physics, but claim that the distinction between exact and approximate laws is too simplistic to taxonomise them. Approximations in chemistry involve diverse kinds of activity and often what counts as a scientific law in chemistry is dictated by the context of its use in scientific practice. This paper addresses the question of what makes chemical laws distinctive independently of the separate question as to how they are related to the laws of physics. From an analysis of some candidate ceteris paribus laws in chemistry, this paper argues that there are two distinct kinds of ceteris paribus laws in chemistry; idealized and approximate chemical laws. Thus, while Christie ( Stud Hist Philos Sci 25:613-629, 1994) and Christie and Christie ( Of minds and molecules. Oxford University Press, New York, pp. 34--50, 2000) are correct to point out that the candidate generalisations in chemistry are diverse and heterogeneous, a distinction between idealizations and approximations can nevertheless be used to successfully taxonomise them.

  13. Test Input Generation for Red-Black Trees using Abstraction

    NASA Technical Reports Server (NTRS)

    Visser, Willem; Pasareanu, Corina S.; Pelanek, Radek

    2005-01-01

    We consider the problem of test input generation for code that manipulates complex data structures. Test inputs are sequences of method calls from the data structure interface. We describe test input generation techniques that rely on state matching to avoid generation of redundant tests. Exhaustive techniques use explicit state model checking to explore all the possible test sequences up to predefined input sizes. Lossy techniques rely on abstraction mappings to compute and store abstract versions of the concrete states; they explore under-approximations of all the possible test sequences. We have implemented the techniques on top of the Java PathFinder model checker and we evaluate them using a Java implementation of red-black trees.

  14. Elastic lattice in an incommensurate background

    SciTech Connect

    Dickman, R.; Chudnovsky, E.M. )

    1995-01-01

    We study a harmonic triangular lattice, which relaxes in the presence of an incommensurate short-wavelength potential. Monte Carlo simulations reveal that the elastic lattice exhibits only short-ranged translational correlations, despite the absence of defects in either lattice. Extended orientational order, however, persists in the presence of the background. Translational correlation lengths exhibit approximate power-law dependence upon cooling rate and background strength. Our results may be relevant to Wigner crystals, atomic monolayers on crystals surfaces, and flux-line and magnetic bubble lattices.

  15. Abstract spatial reasoning as an autistic strength.

    PubMed

    Stevenson, Jennifer L; Gernsbacher, Morton Ann

    2013-01-01

    Autistic individuals typically excel on spatial tests that measure abstract reasoning, such as the Block Design subtest on intelligence test batteries and the Raven's Progressive Matrices nonverbal test of intelligence. Such well-replicated findings suggest that abstract spatial processing is a relative and perhaps absolute strength of autistic individuals. However, previous studies have not systematically varied reasoning level--concrete vs. abstract--and test domain--spatial vs. numerical vs. verbal, which the current study did. Autistic participants (N = 72) and non-autistic participants (N = 72) completed a battery of 12 tests that varied by reasoning level (concrete vs. abstract) and domain (spatial vs. numerical vs. verbal). Autistic participants outperformed non-autistic participants on abstract spatial tests. Non-autistic participants did not outperform autistic participants on any of the three domains (spatial, numerical, and verbal) or at either of the two reasoning levels (concrete and abstract), suggesting similarity in abilities between autistic and non-autistic individuals, with abstract spatial reasoning as an autistic strength. PMID:23533615

  16. String pair production in non homogeneous backgrounds

    NASA Astrophysics Data System (ADS)

    Bolognesi, S.; Rabinovici, E.; Tallarita, G.

    2016-04-01

    We consider string pair production in non homogeneous electric backgrounds. We study several particular configurations which can be addressed with the Euclidean world-sheet instanton technique, the analogue of the world-line instanton for particles. In the first case the string is suspended between two D-branes in flat space-time, in the second case the string lives in AdS and terminates on one D-brane (this realizes the holographic Schwinger effect). In some regions of parameter space the result is well approximated by the known analytical formulas, either the particle pair production in non-homogeneous background or the string pair production in homogeneous background. In other cases we see effects which are intrinsically stringy and related to the non-homogeneity of the background. The pair production is enhanced already for particles in time dependent electric field backgrounds. The string nature enhances this even further. For spacial varying electrical background fields the string pair production is less suppressed than the rate of particle pair production. We discuss in some detail how the critical field is affected by the non-homogeneity, for both time and space dependent electric field backgrouds. We also comment on what could be an interesting new prediction for the small field limit. The third case we consider is pair production in holographic confining backgrounds with homogeneous and non-homogeneous fields.

  17. One sign ion mobile approximation

    NASA Astrophysics Data System (ADS)

    Barbero, G.

    2011-12-01

    The electrical response of an electrolytic cell to an external excitation is discussed in the simple case where only one group of positive and negative ions is present. The particular case where the diffusion coefficients of the negative ions, Dm, is very small with respect to that of the positive ions, Dp, is considered. In this framework, it is discussed under what conditions the one mobile approximation, in which the negative ions are assumed fixed, works well. The analysis is performed by assuming that the external excitation is sinusoidal with circular frequency ω, as that used in the impedance spectroscopy technique. In this framework, we show that there exists a circular frequency, ω*, such that for ω > ω*, the one mobile ion approximation works well. We also show that for Dm ≪ Dp, ω* is independent of Dm.

  18. Testing the frozen flow approximation

    NASA Technical Reports Server (NTRS)

    Lucchin, Francesco; Matarrese, Sabino; Melott, Adrian L.; Moscardini, Lauro

    1993-01-01

    We investigate the accuracy of the frozen-flow approximation (FFA), recently proposed by Matarrese, et al. (1992), for following the nonlinear evolution of cosmological density fluctuations under gravitational instability. We compare a number of statistics between results of the FFA and n-body simulations, including those used by Melott, Pellman & Shandarin (1993) to test the Zel'dovich approximation. The FFA performs reasonably well in a statistical sense, e.g. in reproducing the counts-in-cell distribution, at small scales, but it does poorly in the crosscorrelation with n-body which means it is generally not moving mass to the right place, especially in models with high small-scale power.

  19. The cosmic background explorer

    SciTech Connect

    Gulkis, G. ); Lubin, P.M. ); Meyer, S.S. ); Silverberg, R.F.

    1990-01-01

    Late last year the National Aeronautics and Space Administration launched its first satellite dedicated to the study of phenomena related to the origins of the universe. The satellite, called the Cosmic Background Explorer (COBE), carries three complementary detectors that will make fundamental measurements of the celestial radiation. Part of that radiation is believed to have originated in processes that occurred at the very dawn of the universe. By measuring the remnant radiation at wavelengths from one micrometer to one centimeter across the entire sky, scientists hope to be able to solve many mysteries regarding the origin and evolution of the early universe. Unfortunately, these radiative relics of the early universe are weak and veiled by local astrophysical and terrestrial sources of radiation. The wavelengths of the various cosmic components may also overlap, thereby making the understanding of the diffuse celestial radiation a challenge. Nevertheless, the COBE instruments, with their full-sky coverage, high sensitivity to a wide range of wavelengths and freedom from interference from the earth's atmosphere, will constitute for astrophysicists an observatory of unprecedented sensitivity and scope. The interesting cosmic signals will then be separated from one another and from noncosmic radiation sources by a comprehensive analysis of the data.

  20. Maritime infrared background clutter

    NASA Astrophysics Data System (ADS)

    Schwering, Piet B. W.

    1996-06-01

    The detection of small targets in maritime infrared surveillance is hampered by the presence of clutter. Sea surface structure, reflection and emission changes related to incident angle variations and surface effects are standard features governing the clutter behavior. Also special effects as sun glint and horizon effects play an important role for clutter. In order to optimize the detection process, quantitative clutter estimates are of use for filter settings. We have recorded a large amount of infrared backgrounds in the last few years, during common NATO trials. A large amount of different meteorological conditions took place during the various experiments. A first set of these data have been analyzed to obtain statistical data that represent the infrared scene. We have derived vertical temperature profiles, vertical fluctuation profiles, horizontal correlation coefficients and temporal correlation functions. In this paper we present the first analysis of these data. We are in the process of obtaining a condensed database of information to regenerate clutter images from bulk meteo parameters, and clutter parameters. The clutter and meteo parameters have been used to simulate various infrared scenes. Examples of this simulation process are shown in the presentation. The simulated images are statistically similar to the original images that were used to derive the parameters. A description of the image- generation is presented. Future expansions of the model are discussed.

  1. Biological aerosol background characterization

    NASA Astrophysics Data System (ADS)

    Blatny, Janet; Fountain, Augustus W., III

    2011-05-01

    To provide useful information during military operations, or as part of other security situations, a biological aerosol detector has to respond within seconds or minutes to an attack by virulent biological agents, and with low false alarms. Within this time frame, measuring virulence of a known microorganism is extremely difficult, especially if the microorganism is of unknown antigenic or nucleic acid properties. Measuring "live" characteristics of an organism directly is not generally an option, yet only viable organisms are potentially infectious. Fluorescence based instruments have been designed to optically determine if aerosol particles have viability characteristics. Still, such commercially available biological aerosol detection equipment needs to be improved for their use in military and civil applications. Air has an endogenous population of microorganisms that may interfere with alarm software technologies. To design robust algorithms, a comprehensive knowledge of the airborne biological background content is essential. For this reason, there is a need to study ambient live bacterial populations in as many locations as possible. Doing so will permit collection of data to define diverse biological characteristics that in turn can be used to fine tune alarm algorithms. To avoid false alarms, improving software technologies for biological detectors is a crucial feature requiring considerations of various parameters that can be applied to suppress alarm triggers. This NATO Task Group will aim for developing reference methods for monitoring biological aerosol characteristics to improve alarm algorithms for biological detection. Additionally, they will focus on developing reference standard methodology for monitoring biological aerosol characteristics to reduce false alarm rates.

  2. Approximate Counting of Graphical Realizations

    PubMed Central

    2015-01-01

    In 1999 Kannan, Tetali and Vempala proposed a MCMC method to uniformly sample all possible realizations of a given graphical degree sequence and conjectured its rapidly mixing nature. Recently their conjecture was proved affirmative for regular graphs (by Cooper, Dyer and Greenhill, 2007), for regular directed graphs (by Greenhill, 2011) and for half-regular bipartite graphs (by Miklós, Erdős and Soukup, 2013). Several heuristics on counting the number of possible realizations exist (via sampling processes), and while they work well in practice, so far no approximation guarantees exist for such an approach. This paper is the first to develop a method for counting realizations with provable approximation guarantee. In fact, we solve a slightly more general problem; besides the graphical degree sequence a small set of forbidden edges is also given. We show that for the general problem (which contains the Greenhill problem and the Miklós, Erdős and Soukup problem as special cases) the derived MCMC process is rapidly mixing. Further, we show that this new problem is self-reducible therefore it provides a fully polynomial randomized approximation scheme (a.k.a. FPRAS) for counting of all realizations. PMID:26161994

  3. Computer Experiments for Function Approximations

    SciTech Connect

    Chang, A; Izmailov, I; Rizzo, S; Wynter, S; Alexandrov, O; Tong, C

    2007-10-15

    This research project falls in the domain of response surface methodology, which seeks cost-effective ways to accurately fit an approximate function to experimental data. Modeling and computer simulation are essential tools in modern science and engineering. A computer simulation can be viewed as a function that receives input from a given parameter space and produces an output. Running the simulation repeatedly amounts to an equivalent number of function evaluations, and for complex models, such function evaluations can be very time-consuming. It is then of paramount importance to intelligently choose a relatively small set of sample points in the parameter space at which to evaluate the given function, and then use this information to construct a surrogate function that is close to the original function and takes little time to evaluate. This study was divided into two parts. The first part consisted of comparing four sampling methods and two function approximation methods in terms of efficiency and accuracy for simple test functions. The sampling methods used were Monte Carlo, Quasi-Random LP{sub {tau}}, Maximin Latin Hypercubes, and Orthogonal-Array-Based Latin Hypercubes. The function approximation methods utilized were Multivariate Adaptive Regression Splines (MARS) and Support Vector Machines (SVM). The second part of the study concerned adaptive sampling methods with a focus on creating useful sets of sample points specifically for monotonic functions, functions with a single minimum and functions with a bounded first derivative.

  4. Approximate reasoning using terminological models

    NASA Technical Reports Server (NTRS)

    Yen, John; Vaidya, Nitin

    1992-01-01

    Term Subsumption Systems (TSS) form a knowledge-representation scheme in AI that can express the defining characteristics of concepts through a formal language that has a well-defined semantics and incorporates a reasoning mechanism that can deduce whether one concept subsumes another. However, TSS's have very limited ability to deal with the issue of uncertainty in knowledge bases. The objective of this research is to address issues in combining approximate reasoning with term subsumption systems. To do this, we have extended an existing AI architecture (CLASP) that is built on the top of a term subsumption system (LOOM). First, the assertional component of LOOM has been extended for asserting and representing uncertain propositions. Second, we have extended the pattern matcher of CLASP for plausible rule-based inferences. Third, an approximate reasoning model has been added to facilitate various kinds of approximate reasoning. And finally, the issue of inconsistency in truth values due to inheritance is addressed using justification of those values. This architecture enhances the reasoning capabilities of expert systems by providing support for reasoning under uncertainty using knowledge captured in TSS. Also, as definitional knowledge is explicit and separate from heuristic knowledge for plausible inferences, the maintainability of expert systems could be improved.

  5. Approximate Counting of Graphical Realizations.

    PubMed

    Erdős, Péter L; Kiss, Sándor Z; Miklós, István; Soukup, Lajos

    2015-01-01

    In 1999 Kannan, Tetali and Vempala proposed a MCMC method to uniformly sample all possible realizations of a given graphical degree sequence and conjectured its rapidly mixing nature. Recently their conjecture was proved affirmative for regular graphs (by Cooper, Dyer and Greenhill, 2007), for regular directed graphs (by Greenhill, 2011) and for half-regular bipartite graphs (by Miklós, Erdős and Soukup, 2013). Several heuristics on counting the number of possible realizations exist (via sampling processes), and while they work well in practice, so far no approximation guarantees exist for such an approach. This paper is the first to develop a method for counting realizations with provable approximation guarantee. In fact, we solve a slightly more general problem; besides the graphical degree sequence a small set of forbidden edges is also given. We show that for the general problem (which contains the Greenhill problem and the Miklós, Erdős and Soukup problem as special cases) the derived MCMC process is rapidly mixing. Further, we show that this new problem is self-reducible therefore it provides a fully polynomial randomized approximation scheme (a.k.a. FPRAS) for counting of all realizations. PMID:26161994

  6. Writing, reviewing, and presenting an abstract.

    PubMed

    Strauss, R G

    1991-01-01

    Abstracts afford an opportunity to report data at professional meetings and, when published, in the literature. Accordingly, they should be prepared with great care. When writing an abstract, anticipate questions the reviewer will ask when judging it and provide complete answers. The presentation of an abstract should follow similar thought processes. State why a problem or question is important, how you addressed it, what you found, and how your findings can be applied to the issue at hand. Slides and text should provide coordinated visual and auditory input, respectively, to ensure complete comprehension. PMID:1816248

  7. TQM: A bibliography with abstracts. [total quality management

    NASA Technical Reports Server (NTRS)

    Gottlich, Gretchen L. (Editor)

    1992-01-01

    This document is designed to function as a special resource for NASA Langley scientists, engineers, and managers during the introduction and development of total quality management (TQM) practices at the Center. It lists approximately 300 bibliographic citations for articles and reports dealing with various aspects of TQM. Abstracts are also available for the majority of the citations. Citations are organized by broad subject areas, including case studies, customer service, senior management, leadership, communication tools, TQM basics, applications, and implementation. An introduction and indexes provide additional information on arrangement and availability of these materials.

  8. Constraint-Based Abstract Semantics for Temporal Logic: A Direct Approach to Design and Implementation

    NASA Astrophysics Data System (ADS)

    Banda, Gourinath; Gallagher, John P.

    interpretation provides a practical approach to verifying properties of infinite-state systems. We apply the framework of abstract interpretation to derive an abstract semantic function for the modal μ-calculus, which is the basis for abstract model checking. The abstract semantic function is constructed directly from the standard concrete semantics together with a Galois connection between the concrete state-space and an abstract domain. There is no need for mixed or modal transition systems to abstract arbitrary temporal properties, as in previous work in the area of abstract model checking. Using the modal μ-calculus to implement CTL, the abstract semantics gives an over-approximation of the set of states in which an arbitrary CTL formula holds. Then we show that this leads directly to an effective implementation of an abstract model checking algorithm for CTL using abstract domains based on linear constraints. The implementation of the abstract semantic function makes use of an SMT solver. We describe an implemented system for proving properties of linear hybrid automata and give some experimental results.

  9. Pulmonary toxicology of respirable particles. [Lead abstract

    SciTech Connect

    Sanders, C.L.; Cross, F.T.; Dagle, G.E.; Mahaffey, J.A.

    1980-09-01

    Separate abstracts were prepared for the 44 papers presented in these proceedings. The last paper (Stannard) in the proceedings is an historical review of the field of inhalation toxicology and is not included in the analytics. (DS)

  10. OIL POLLUTION ABSTRACTS. VOLUME 6, NUMBER 2

    EPA Science Inventory

    Oil Pollution Abstracts (formerly entitled Oil Pollution Reports) is a quarterly compilation of current literature and research project summaries. Comprehensive coverage of oil pollution and its prevention and control is provided, with emphasis on the aquatic environment. This is...

  11. Program Aims at Improving Abstract Reasoning

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1977

    1977-01-01

    Describes a program being conducted within the chemistry department of Xavier University, New Orleans, Louisiana, to improve the abstract reasoning abilities of freshmen science majors. The project is based upon the philosophy developed by Jean Piaget. (SL)

  12. Introducing Abstraction to Junior High Students.

    ERIC Educational Resources Information Center

    Costanzo, Nancy

    1981-01-01

    Suggests a way to introduce abstract art to junior high school students who, more than students of any other age, emphasize realism both in their artwork and in their appreciation of works of art. (Author/SJL)

  13. Masking failures of multidimensional sensors (extended abstract)

    NASA Technical Reports Server (NTRS)

    Chew, Paul; Marzullo, Keith

    1990-01-01

    When a computer monitors a physical process, the computer uses sensors to determine the values of the physical variables that represent the state of the process. A sensor can sometimes fail, however, and in the worst case report a value completely unrelated to the true physical value. The work described is motivated by a methodology for transforming a process control program that can not tolerate sensor failure into one that can. In this methodology, a reliable abstract sensor is created by combining information from several real sensors that measure the same physical value. To be useful, an abstract sensor must deliver reasonably accurate information at reasonable computational cost. Sensors are considered that deliver multidimensional values (e.g., location or velocity in three dimensions, or both temperature and pressure). Geometric techniques are used to derive upper bounds on abstract sensor accuracy and to develop efficient algorithms for implementing abstract sensors.

  14. 1. SOUTH FACADE, BUILDING 742 IN BACKGROUND. Rocky Mountain ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. SOUTH FACADE, BUILDING 742 IN BACKGROUND. - Rocky Mountain Arsenal, Tank House, Quadrant 1, approximately 1000 feet South of December Seventh Avenue; 2200 feet East of D Street, Commerce City, Adams County, CO

  15. House, east side, looking west (bunkhouse in background left) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    House, east side, looking west (bunkhouse in background left) - John Moulton Homestead, House, Approximately 70 feet west of Mormon Row Road, and 300 feet north of Antelope Flats Road, Kelly, Teton County, WY

  16. Earth Sciences Division collected abstracts: 1980

    SciTech Connect

    Henry, A.L.; Hornady, B.F.

    1981-10-15

    This report is a compilation of abstracts of papers, reports, and talks presented during 1980 at national and international meetings by members of the Earth Sciences Division, Lawrence Livermore National Laboratory. The arrangement is alphabetical (by author). For a given report, a bibliographic reference appears under the name of each coauthor, but the abstract itself is given only under the name of the first author (indicated in capital letters) or the first Earth Sciences Division author.

  17. Finding Feasible Abstract Counter-Examples

    NASA Technical Reports Server (NTRS)

    Pasareanu, Corina S.; Dwyer, Matthew B.; Visser, Willem; Clancy, Daniel (Technical Monitor)

    2002-01-01

    A strength of model checking is its ability to automate the detection of subtle system errors and produce traces that exhibit those errors. Given the high computational cost of model checking most researchers advocate the use of aggressive property-preserving abstractions. Unfortunately, the more aggressively a system is abstracted the more infeasible behavior it will have. Thus, while abstraction enables efficient model checking it also threatens the usefulness of model checking as a defect detection tool, since it may be difficult to determine whether a counter-example is feasible and hence worth developer time to analyze. We have explored several strategies for addressing this problem by extending an explicit-state model checker, Java PathFinder (JPF), to search for and analyze counter-examples in the presence of abstractions. We demonstrate that these techniques effectively preserve the defect detection ability of model checking in the presence of aggressive abstraction by applying them to check properties of several abstracted multi-threaded Java programs. These new capabilities are not specific to JPF and can be easily adapted to other model checking frameworks; we describe how this was done for the Bandera toolset.

  18. Background sources in optical communications

    NASA Technical Reports Server (NTRS)

    Vilnrotter, V. A.

    1983-01-01

    The characterization and measurement of background radiation relevant to optical communications system performance is addressed. The necessary optical receiver parameters are described, and radiometric concepts required for the calculation of collected background power are developed. The most important components of optical background power are discussed, and their contribution to the total collected background power in various communications scenarios is examined.

  19. Semigroup theory and numerical approximation for equations in linear viscoelasticity

    NASA Technical Reports Server (NTRS)

    Fabiano, R. H.; Ito, K.

    1990-01-01

    A class of abstract integrodifferential equations used to model linear viscoelastic beams is investigated analytically, applying a Hilbert-space approach. The basic equation is rewritten as a Cauchy problem, and its well-posedness is demonstrated. Finite-dimensional subspaces of the state space and an estimate of the state operator are obtained; approximation schemes for the equations are constructed; and the convergence is proved using the Trotter-Kato theorem of linear semigroup theory. The actual convergence behavior of different approximations is demonstrated in numerical computations, and the results are presented in tables.

  20. The Anisotropy of the Microwave Background to l=3500: Mosaic Observations with the Cosmic Background Imager

    NASA Technical Reports Server (NTRS)

    Pearson, T. J.; Mason, B. S.; Readhead, A. C. S.; Shepherd, M. C.; Sievers, J. L.; Udomprasert, P. S.; Cartwright, J. K.; Farmer, A. J.; Padin, S.; Myers, S. T.; Six, N. Frank (Technical Monitor)

    2002-01-01

    Using the Cosmic Background Imager, a 13-element interferometer array operating in the 26-36 GHz frequency band, we have observed 40 deg (sup 2) of sky in three pairs of fields, each approximately 145 feet x 165 feet, using overlapping pointings: (mosaicing). We present images and power spectra of the cosmic microwave background radiation in these mosaic fields. We remove ground radiation and other low-level contaminating signals by differencing matched observations of the fields in each pair. The primary foreground contamination is due to point sources (radio galaxies and quasars). We have subtracted the strongest sources from the data using higher-resolution measurements, and we have projected out the response to other sources of known position in the power-spectrum analysis. The images show features on scales approximately 6 feet-15 feet, corresponding to masses approximately 5-80 x 10(exp 14) solar mass at the surface of last scattering, which are likely to be the seeds of clusters of galaxies. The power spectrum estimates have a resolution delta l approximately 200 and are consistent with earlier results in the multipole range l approximately less than 1000. The power spectrum is detected with high signal-to-noise ratio in the range 300 approximately less than l approximately less than 1700. For 1700 approximately less than l approximately less than 3000 the observations are consistent with the results from more sensitive CBI deep-field observations. The results agree with the extrapolation of cosmological models fitted to observations at lower l, and show the predicted drop at high l (the "damping tail").

  1. Improved non-approximability results

    SciTech Connect

    Bellare, M.; Sudan, M.

    1994-12-31

    We indicate strong non-approximability factors for central problems: N{sup 1/4} for Max Clique; N{sup 1/10} for Chromatic Number; and 66/65 for Max 3SAT. Underlying the Max Clique result is a proof system in which the verifier examines only three {open_quotes}free bits{close_quotes} to attain an error of 1/2. Underlying the Chromatic Number result is a reduction from Max Clique which is more efficient than previous ones.

  2. Quantum tunneling beyond semiclassical approximation

    NASA Astrophysics Data System (ADS)

    Banerjee, Rabin; Ranjan Majhi, Bibhas

    2008-06-01

    Hawking radiation as tunneling by Hamilton-Jacobi method beyond semiclassical approximation is analysed. We compute all quantum corrections in the single particle action revealing that these are proportional to the usual semiclassical contribution. We show that a simple choice of the proportionality constants reproduces the one loop back reaction effect in the spacetime, found by conformal field theory methods, which modifies the Hawking temperature of the black hole. Using the law of black hole mechanics we give the corrections to the Bekenstein-Hawking area law following from the modified Hawking temperature. Some examples are explicitly worked out.

  3. Fermion tunneling beyond semiclassical approximation

    NASA Astrophysics Data System (ADS)

    Majhi, Bibhas Ranjan

    2009-02-01

    Applying the Hamilton-Jacobi method beyond the semiclassical approximation prescribed in R. Banerjee and B. R. Majhi, J. High Energy Phys.JHEPFG1029-8479 06 (2008) 09510.1088/1126-6708/2008/06/095 for the scalar particle, Hawking radiation as tunneling of the Dirac particle through an event horizon is analyzed. We show that, as before, all quantum corrections in the single particle action are proportional to the usual semiclassical contribution. We also compute the modifications to the Hawking temperature and Bekenstein-Hawking entropy for the Schwarzschild black hole. Finally, the coefficient of the logarithmic correction to entropy is shown to be related with the trace anomaly.

  4. Generalized Gradient Approximation Made Simple

    SciTech Connect

    Perdew, J.P.; Burke, K.; Ernzerhof, M.

    1996-10-01

    Generalized gradient approximations (GGA{close_quote}s) for the exchange-correlation energy improve upon the local spin density (LSD) description of atoms, molecules, and solids. We present a simple derivation of a simple GGA, in which all parameters (other than those in LSD) are fundamental constants. Only general features of the detailed construction underlying the Perdew-Wang 1991 (PW91) GGA are invoked. Improvements over PW91 include an accurate description of the linear response of the uniform electron gas, correct behavior under uniform scaling, and a smoother potential. {copyright} {ital 1996 The American Physical Society.}

  5. More insight into the fate of biomedical meeting abstracts: a systematic review

    PubMed Central

    von Elm, Erik; Costanza, Michael C; Walder, Bernhard; Tramèr, Martin R

    2003-01-01

    Background It has been estimated that about 45% of abstracts that are accepted for presentation at biomedical meetings will subsequently be published in full. The acceptance of abstracts at meetings and their fate after initial rejection are less well understood. We set out to estimate the proportion of abstracts submitted to meetings that are eventually published as full reports, and to explore factors that are associated with meeting acceptance and successful publication. Methods Studies analysing acceptance of abstracts at biomedical meetings or their subsequent full publication were searched in MEDLINE, OLDMEDLINE, EMBASE, Cochrane Library, CINAHL, BIOSIS, Science Citation Index Expanded, and by hand searching of bibliographies and proceedings. We estimated rates of abstract acceptance and of subsequent full publication, and identified abstract and meeting characteristics associated with acceptance and publication, using logistic regression analysis, survival-type analysis, and meta-analysis. Results Analysed meetings were held between 1957 and 1999. Of 14945 abstracts that were submitted to 43 meetings, 46% were accepted. The rate of full publication was studied with 19123 abstracts that were presented at 234 meetings. Using survival-type analysis, we estimated that 27% were published after two, 41% after four, and 44% after six years. Of 2412 abstracts that were rejected at 24 meetings, 27% were published despite rejection. Factors associated with both abstract acceptance and subsequent publication were basic science and positive study outcome. Large meetings and those held outside the US were more likely to accept abstracts. Abstracts were more likely to be published subsequently if presented either orally, at small meetings, or at a US meeting. Abstract acceptance itself was strongly associated with full publication. Conclusions About one third of abstracts submitted to biomedical meetings were published as full reports. Acceptance at meetings and

  6. Wavelet Approximation in Data Assimilation

    NASA Technical Reports Server (NTRS)

    Tangborn, Andrew; Atlas, Robert (Technical Monitor)

    2002-01-01

    Estimation of the state of the atmosphere with the Kalman filter remains a distant goal because of high computational cost of evolving the error covariance for both linear and nonlinear systems. Wavelet approximation is presented here as a possible solution that efficiently compresses both global and local covariance information. We demonstrate the compression characteristics on the the error correlation field from a global two-dimensional chemical constituent assimilation, and implement an adaptive wavelet approximation scheme on the assimilation of the one-dimensional Burger's equation. In the former problem, we show that 99%, of the error correlation can be represented by just 3% of the wavelet coefficients, with good representation of localized features. In the Burger's equation assimilation, the discrete linearized equations (tangent linear model) and analysis covariance are projected onto a wavelet basis and truncated to just 6%, of the coefficients. A nearly optimal forecast is achieved and we show that errors due to truncation of the dynamics are no greater than the errors due to covariance truncation.

  7. Plasma Physics Approximations in Ares

    SciTech Connect

    Managan, R. A.

    2015-01-08

    Lee & More derived analytic forms for the transport properties of a plasma. Many hydro-codes use their formulae for electrical and thermal conductivity. The coefficients are complex functions of Fermi-Dirac integrals, Fn( μ/θ ), the chemical potential, μ or ζ = ln(1+e μ/θ ), and the temperature, θ = kT. Since these formulae are expensive to compute, rational function approximations were fit to them. Approximations are also used to find the chemical potential, either μ or ζ . The fits use ζ as the independent variable instead of μ/θ . New fits are provided for Aα (ζ ),Aβ (ζ ), ζ, f(ζ ) = (1 + e-μ/θ)F1/2(μ/θ), F1/2'/F1/2, Fcα, and Fcβ. In each case the relative error of the fit is minimized since the functions can vary by many orders of magnitude. The new fits are designed to exactly preserve the limiting values in the non-degenerate and highly degenerate limits or as ζ→ 0 or ∞. The original fits due to Lee & More and George Zimmerman are presented for comparison.

  8. Interplay of approximate planning strategies.

    PubMed

    Huys, Quentin J M; Lally, Níall; Faulkner, Paul; Eshel, Neir; Seifritz, Erich; Gershman, Samuel J; Dayan, Peter; Roiser, Jonathan P

    2015-03-10

    Humans routinely formulate plans in domains so complex that even the most powerful computers are taxed. To do so, they seem to avail themselves of many strategies and heuristics that efficiently simplify, approximate, and hierarchically decompose hard tasks into simpler subtasks. Theoretical and cognitive research has revealed several such strategies; however, little is known about their establishment, interaction, and efficiency. Here, we use model-based behavioral analysis to provide a detailed examination of the performance of human subjects in a moderately deep planning task. We find that subjects exploit the structure of the domain to establish subgoals in a way that achieves a nearly maximal reduction in the cost of computing values of choices, but then combine partial searches with greedy local steps to solve subtasks, and maladaptively prune the decision trees of subtasks in a reflexive manner upon encountering salient losses. Subjects come idiosyncratically to favor particular sequences of actions to achieve subgoals, creating novel complex actions or "options." PMID:25675480

  9. Approximating metal-insulator transitions

    NASA Astrophysics Data System (ADS)

    Danieli, Carlo; Rayanov, Kristian; Pavlov, Boris; Martin, Gaven; Flach, Sergej

    2015-12-01

    We consider quantum wave propagation in one-dimensional quasiperiodic lattices. We propose an iterative construction of quasiperiodic potentials from sequences of potentials with increasing spatial period. At each finite iteration step, the eigenstates reflect the properties of the limiting quasiperiodic potential properties up to a controlled maximum system size. We then observe approximate Metal-Insulator Transitions (MIT) at the finite iteration steps. We also report evidence on mobility edges, which are at variance to the celebrated Aubry-André model. The dynamics near the MIT shows a critical slowing down of the ballistic group velocity in the metallic phase, similar to the divergence of the localization length in the insulating phase.

  10. Strong shock implosion, approximate solution

    NASA Astrophysics Data System (ADS)

    Fujimoto, Y.; Mishkin, E. A.; Alejaldre, C.

    1983-01-01

    The self-similar, center-bound motion of a strong spherical, or cylindrical, shock wave moving through an ideal gas with a constant, γ= cp/ cv, is considered and a linearized, approximate solution is derived. An X, Y phase plane of the self-similar solution is defined and the representative curved of the system behind the shock front is replaced by a straight line connecting the mappings of the shock front with that of its tail. The reduced pressure P(ξ), density R(ξ) and velocity U1(ξ) are found in closed, quite accurate, form. Comparison with numerically obtained results, for γ= {5}/{3} and γ= {7}/{5}, is shown.

  11. Approximate analytic solutions to the NPDD: Short exposure approximations

    NASA Astrophysics Data System (ADS)

    Close, Ciara E.; Sheridan, John T.

    2014-04-01

    There have been many attempts to accurately describe the photochemical processes that take places in photopolymer materials. As the models have become more accurate, solving them has become more numerically intensive and more 'opaque'. Recent models incorporate the major photochemical reactions taking place as well as the diffusion effects resulting from the photo-polymerisation process, and have accurately described these processes in a number of different materials. It is our aim to develop accessible mathematical expressions which provide physical insights and simple quantitative predictions of practical value to material designers and users. In this paper, starting with the Non-Local Photo-Polymerisation Driven Diffusion (NPDD) model coupled integro-differential equations, we first simplify these equations and validate the accuracy of the resulting approximate model. This new set of governing equations are then used to produce accurate analytic solutions (polynomials) describing the evolution of the monomer and polymer concentrations, and the grating refractive index modulation, in the case of short low intensity sinusoidal exposures. The physical significance of the results and their consequences for holographic data storage (HDS) are then discussed.

  12. Information Leakage Analysis by Abstract Interpretation

    NASA Astrophysics Data System (ADS)

    Zanioli, Matteo; Cortesi, Agostino

    Protecting the confidentiality of information stored in a computer system or transmitted over a public network is a relevant problem in computer security. The approach of information flow analysis involves performing a static analysis of the program with the aim of proving that there will not be leaks of sensitive information. In this paper we propose a new domain that combines variable dependency analysis, based on propositional formulas, and variables' value analysis, based on polyhedra. The resulting analysis is strictly more accurate than the state of the art abstract interpretation based analyses for information leakage detection. Its modular construction allows to deal with the tradeoff between efficiency and accuracy by tuning the granularity of the abstraction and the complexity of the abstract operators.

  13. Fall Meeting abstract submission inspires science poetry

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2011-08-01

    When the 4 August deadline for submitting Fall Meeting abstracts passed, AGU had received more than 20,000 abstracts, a record-breaking number. The submission process had an unexpected by-product: It inspired some scientists to write haiku on Twitter. (Haiku is a form of Japanese poetry typically having three lines, the first with five syllables, the second with seven, and the third with five.) The following are examples of the haiku tweets, with the hashtag #AGU11AbstractHaiku. (For those who want to keep updated about the Fall Meeting on Twitter, the hashtag is #AGU11.) For more information about the meeting, including registration and housing, visit http://sites.agu.org/fallmeeting/.

  14. Abstracting and indexing in the medical sciences.

    PubMed

    Welt, I D

    1962-07-01

    Abstracts and indexes constitute the most popular means of assuring adequate retrieval of the many thousands of papers published every year in the ever expanding field of medicine. Different types of abstracts and indexes are available for different purposes and to meet varying user requirements. The problem of "keeping up" with developments in one's own field of endeavour can usually be solved by qualified abstractors. Most indexes serve the purpose of assuring the retrieval of pertinent documents. However, in order to retrieve specific pieces of information which are absolutely indispensible to the medical practitioner or scientist, a new approach is needed. This technique, which is termed the "combined index-abstract" method, has been employed successfully for the handling of a large body of specific items of information in a restricted area of experimental and clinical pharmacology. PMID:21735878

  15. Computing abstraction hierarchies by numerical simulation

    SciTech Connect

    Bundy, A.; Giunchiglia, F.; Sebastiani, R.; Walsh, T.

    1996-12-31

    We present a novel method for building ABSTRIPS-style abstraction hierarchies in planning. The aim of this method is to minimize the amount of backtracking between abstraction levels. Previous approaches have determined the criticality of operator preconditions by reasoning about plans directly. Here, we adopt a simpler and faster approach where we use numerical simulation of the planning process. We demonstrate the theoretical advantages of our approach by identifying some simple properties lacking in previous approaches but possessed by our method. We demonstrate the empirical advantages of our approach by a set of four benchmark experiments using the ABTWEAK system. We compare the quality of the abstraction hierarchies generated with those built by the ALPINE and HIGHPOINT algorithms.

  16. Dual-tracer background subtraction approach for fluorescent molecular tomography

    PubMed Central

    Holt, Robert W.; El-Ghussein, Fadi; Davis, Scott C.; Samkoe, Kimberley S.; Gunn, Jason R.; Leblond, Frederic

    2013-01-01

    Abstract. Diffuse fluorescence tomography requires high contrast-to-background ratios to accurately reconstruct inclusions of interest. This is a problem when imaging the uptake of fluorescently labeled molecularly targeted tracers in tissue, which can result in high levels of heterogeneously distributed background uptake. We present a dual-tracer background subtraction approach, wherein signal from the uptake of an untargeted tracer is subtracted from targeted tracer signal prior to image reconstruction, resulting in maps of targeted tracer binding. The approach is demonstrated in simulations, a phantom study, and in a mouse glioma imaging study, demonstrating substantial improvement over conventional and homogenous background subtraction image reconstruction approaches. PMID:23292612

  17. Earth Sciences Division collected abstracts: 1979

    SciTech Connect

    Henry, A.L.; Schwartz, L.L.

    1980-04-30

    This report is a compilation of abstracts of papers, internal reports, and talks presented during 1979 at national and international meetings by members of the Earth Sciences Division, Lawrence Livermore Laboratory. The arrangement is alphabetical (by author). For a given report, a bibliographic reference appears under the name of each coauthor, but the abstract iself is given only under the name of the first author or the first Earth Sciences Division author. A topical index at the end of the report provides useful cross references, while indicating major areas of research interest in the Earth Sciences Division.

  18. 2011 statistical abstract of the United States

    USGS Publications Warehouse

    Krisanda, Joseph M.

    2011-01-01

    The Statistical Abstract of the United States, published since 1878, is the authoritative and comprehensive summary of statistics on the social, political, and economic organization of the United States.


    Use the Abstract as a convenient volume for statistical reference, and as a guide to sources of more information both in print and on the Web.


    Sources of data include the Census Bureau, Bureau of Labor Statistics, Bureau of Economic Analysis, and many other Federal agencies and private organizations.

  19. Lunar ash flows - Isothermal approximation.

    NASA Technical Reports Server (NTRS)

    Pai, S. I.; Hsieh, T.; O'Keefe, J. A.

    1972-01-01

    Suggestion of the ash flow mechanism as one of the major processes required to account for some features of lunar soil. First the observational background and the gardening hypothesis are reviewed, and the shortcomings of the gardening hypothesis are shown. Then a general description of the lunar ash flow is given, and a simple mathematical model of the isothermal lunar ash flow is worked out with numerical examples to show the differences between the lunar and the terrestrial ash flow. The important parameters of the ash flow process are isolated and analyzed. It appears that the lunar surface layer in the maria is not a residual mantle rock (regolith) but a series of ash flows due, at least in part, to great meteorite impacts. The possibility of a volcanic contribution is not excluded. Some further analytic research on lunar ash flows is recommended.

  20. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 13)

    NASA Technical Reports Server (NTRS)

    1978-01-01

    This bibliography is issued in two sections: Section 1 - Abstracts, and Section 2 - Indexes. This issue of the Abstract Section cites 161 patents and applications for patent introduced into the NASA scientific and technical information system during the period January 1978 through June 1978. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent.

  1. Beam induced backgrounds: CDF experience

    SciTech Connect

    Tesarek, R.J.; /Fermilab

    2008-05-01

    We summarize the experiences of the Collider Detector at Fermilab (CDF) experiment in the presence of backgrounds originating from the counter circulating beams in the Fermilab Tevatron. These backgrounds are measured and their sources identified. Finally, we outline the strategies employed to reduce the effects of these backgrounds on the experiment.

  2. Background reduction in the SNO+ experiment

    NASA Astrophysics Data System (ADS)

    Segui, L.

    2015-08-01

    SNO+ is a large multi-purpose liquid scintillator experiment, which first aim is to detect the neutrinoless double beta decay of 130Te. It is placed at SNOLAB, at 6000 m.w.e. and it is based on the SNO infrastructure. SNO+ will contain approximately 780 tonnes of liquid scintillator, loaded with 130Te inside an acrylic vessel (AV) with an external volume of ultra pure water to reduce the external backgrounds. Light produced in the scintillator by the interaction of particles will be detected with about 9,000 photomultiplier's. For the neutrinoless double beta decay phase, due to its the extremely low rate expected, the control, knowledge and reduction of the background is essential. Moreover, it will also benefit other phases of the experiment focused on the study of solar neutrinos, nucleon decay, geoneutrinos and supernovae. In order to reduce the internal background level, a novel purification technique for tellurium loaded scintillators has been developed by the collaboration that reduces the U/Th concentration and several cosmic-activated isotopes by at least a factor 102 -103 in a single pass. In addition, different rejection techniques have been developed for the remaining internal backgrounds based on Monte-Carlo simulations. In this work, the scintillator purification technique and the levels obtained with it will be discussed. Furthermore, an overview of the different backgrounds for the double-beta phase will be presented, highlighting some of the techniques developed to reject the remained decays based on their expected timing differences.

  3. A review on natural background radiation

    PubMed Central

    Shahbazi-Gahrouei, Daryoush; Gholami, Mehrdad; Setayandeh, Samaneh

    2013-01-01

    The world is naturally radioactive and approximately 82% of human-absorbed radiation doses, which are out of control, arise from natural sources such as cosmic, terrestrial, and exposure from inhalation or intake radiation sources. In recent years, several international studies have been carried out, which have reported different values regarding the effect of background radiation on human health. Gamma radiation emitted from natural sources (background radiation) is largely due to primordial radionuclides, mainly 232Th and 238U series, and their decay products, as well as 40K, which exist at trace levels in the earth's crust. Their concentrations in soil, sands, and rocks depend on the local geology of each region in the world. Naturally occurring radioactive materials generally contain terrestrial-origin radionuclides, left over since the creation of the earth. In addition, the existence of some springs and quarries increases the dose rate of background radiation in some regions that are known as high level background radiation regions. The type of building materials used in houses can also affect the dose rate of background radiations. The present review article was carried out to consider all of the natural radiations, including cosmic, terrestrial, and food radiation. PMID:24223380

  4. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 07)

    NASA Technical Reports Server (NTRS)

    1975-01-01

    This bibliography is issued in two sections: Section 1 - Abstracts, and Section 2 - Indexes. This issue of the Abstract Section cites 158 patents and applications for patent introduced into the NASA scientific and technical information system during the period of January 1975 through June 1975. Each entry in the Abstract Section consists of a citation, an abstract, and, in most cases, a key illustration selected from the patent or application for patent. This issue of the Index Section contains entries for 2830 patent and application for patent citations covering the period May 1969 through June 1975. The index section contains five indexes -- subject, inventor, source, number and accession number.

  5. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 09)

    NASA Technical Reports Server (NTRS)

    1976-01-01

    This bibliography is issued in two sections: Section 1 - Abstracts, and Section 2 - Indexes. This issue of the Abstract Section cites 200 patents and applications for patent introduced into the NASA scientific and technical information system during the period of January 1976 through June 1976. Each entry in the Abstract Section consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent. This issue of the Index Section contains entries for 2994 patent and application for patent citations covering the period May 1969 through June 1976. The Index Section contains five indexes -- subject, inventor, source, number and accession number.

  6. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 08)

    NASA Technical Reports Server (NTRS)

    1976-01-01

    This bibliography is issued in two sections; abstracts and indexes. The Abstract Section cites 180 patents and applications for patents introduced into the NASA scientific and technical information system during the period of July 1975 through December 1975. Each entry in the Abstract Section consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent. The index Section contains entries for 2,905 patents and applications for patent citations covering the period May 1969 through December 1975. The Index Section contains five indexes -- subject, inventor, source, number and accession number.

  7. An analytical approach for treating background in spectral analysis measurements

    NASA Astrophysics Data System (ADS)

    Miller, Ian; Holmes, Thomas W.; Gardner, Robin P.

    2015-11-01

    A method of determining the spectral shape of background radiation present in experimental spectra via a mathematical approach is presented. Elements of interest will be subtracted from an experimental spectrum using the linear correlation coefficient across a characteristic peak to determine their contribution. Once all elements of interest are removed, the remainder of the experimental spectrum should represent an approximation of the background. This approximation can then be used in conjunction with library least-squares to determine the background and elemental contributions to the unknown spectrum.

  8. Function approximation in inhibitory networks.

    PubMed

    Tripp, Bryan; Eliasmith, Chris

    2016-05-01

    In performance-optimized artificial neural networks, such as convolutional networks, each neuron makes excitatory connections with some of its targets and inhibitory connections with others. In contrast, physiological neurons are typically either excitatory or inhibitory, not both. This is a puzzle, because it seems to constrain computation, and because there are several counter-examples that suggest that it may not be a physiological necessity. Parisien et al. (2008) showed that any mixture of excitatory and inhibitory functional connections could be realized by a purely excitatory projection in parallel with a two-synapse projection through an inhibitory population. They showed that this works well with ratios of excitatory and inhibitory neurons that are realistic for the neocortex, suggesting that perhaps the cortex efficiently works around this apparent computational constraint. Extending this work, we show here that mixed excitatory and inhibitory functional connections can also be realized in networks that are dominated by inhibition, such as those of the basal ganglia. Further, we show that the function-approximation capacity of such connections is comparable to that of idealized mixed-weight connections. We also study whether such connections are viable in recurrent networks, and find that such recurrent networks can flexibly exhibit a wide range of dynamics. These results offer a new perspective on computation in the basal ganglia, and also perhaps on inhibitory networks within the cortex. PMID:26963256

  9. Interplay of approximate planning strategies

    PubMed Central

    Huys, Quentin J. M.; Lally, Níall; Faulkner, Paul; Eshel, Neir; Seifritz, Erich; Gershman, Samuel J.; Dayan, Peter; Roiser, Jonathan P.

    2015-01-01

    Humans routinely formulate plans in domains so complex that even the most powerful computers are taxed. To do so, they seem to avail themselves of many strategies and heuristics that efficiently simplify, approximate, and hierarchically decompose hard tasks into simpler subtasks. Theoretical and cognitive research has revealed several such strategies; however, little is known about their establishment, interaction, and efficiency. Here, we use model-based behavioral analysis to provide a detailed examination of the performance of human subjects in a moderately deep planning task. We find that subjects exploit the structure of the domain to establish subgoals in a way that achieves a nearly maximal reduction in the cost of computing values of choices, but then combine partial searches with greedy local steps to solve subtasks, and maladaptively prune the decision trees of subtasks in a reflexive manner upon encountering salient losses. Subjects come idiosyncratically to favor particular sequences of actions to achieve subgoals, creating novel complex actions or “options.” PMID:25675480

  10. Multidimensional stochastic approximation Monte Carlo.

    PubMed

    Zablotskiy, Sergey V; Ivanov, Victor A; Paul, Wolfgang

    2016-06-01

    Stochastic Approximation Monte Carlo (SAMC) has been established as a mathematically founded powerful flat-histogram Monte Carlo method, used to determine the density of states, g(E), of a model system. We show here how it can be generalized for the determination of multidimensional probability distributions (or equivalently densities of states) of macroscopic or mesoscopic variables defined on the space of microstates of a statistical mechanical system. This establishes this method as a systematic way for coarse graining a model system, or, in other words, for performing a renormalization group step on a model. We discuss the formulation of the Kadanoff block spin transformation and the coarse-graining procedure for polymer models in this language. We also apply it to a standard case in the literature of two-dimensional densities of states, where two competing energetic effects are present g(E_{1},E_{2}). We show when and why care has to be exercised when obtaining the microcanonical density of states g(E_{1}+E_{2}) from g(E_{1},E_{2}). PMID:27415383

  11. Decision analysis with approximate probabilities

    NASA Technical Reports Server (NTRS)

    Whalen, Thomas

    1992-01-01

    This paper concerns decisions under uncertainty in which the probabilities of the states of nature are only approximately known. Decision problems involving three states of nature are studied. This is due to the fact that some key issues do not arise in two-state problems, while probability spaces with more than three states of nature are essentially impossible to graph. The primary focus is on two levels of probabilistic information. In one level, the three probabilities are separately rounded to the nearest tenth. This can lead to sets of rounded probabilities which add up to 0.9, 1.0, or 1.1. In the other level, probabilities are rounded to the nearest tenth in such a way that the rounded probabilities are forced to sum to 1.0. For comparison, six additional levels of probabilistic information, previously analyzed, were also included in the present analysis. A simulation experiment compared four criteria for decisionmaking using linearly constrained probabilities (Maximin, Midpoint, Standard Laplace, and Extended Laplace) under the eight different levels of information about probability. The Extended Laplace criterion, which uses a second order maximum entropy principle, performed best overall.

  12. Multidimensional stochastic approximation Monte Carlo

    NASA Astrophysics Data System (ADS)

    Zablotskiy, Sergey V.; Ivanov, Victor A.; Paul, Wolfgang

    2016-06-01

    Stochastic Approximation Monte Carlo (SAMC) has been established as a mathematically founded powerful flat-histogram Monte Carlo method, used to determine the density of states, g (E ) , of a model system. We show here how it can be generalized for the determination of multidimensional probability distributions (or equivalently densities of states) of macroscopic or mesoscopic variables defined on the space of microstates of a statistical mechanical system. This establishes this method as a systematic way for coarse graining a model system, or, in other words, for performing a renormalization group step on a model. We discuss the formulation of the Kadanoff block spin transformation and the coarse-graining procedure for polymer models in this language. We also apply it to a standard case in the literature of two-dimensional densities of states, where two competing energetic effects are present g (E1,E2) . We show when and why care has to be exercised when obtaining the microcanonical density of states g (E1+E2) from g (E1,E2) .

  13. Adult Education Dissertation Abstracts: 1968-1969.

    ERIC Educational Resources Information Center

    Grabowski, Stanley M., Ed.; Loague, Nehume, Ed.

    This bibliography contains citations, abstracts, and ordering information for 303 dissertations pertinent to the education or training of adults. Studies are classified by broad subject headings used in the ERIC Clearinghouse on Adult Education. Each section of the classification is identified by a four-digit number, with a one-, two-, or…

  14. Carbon Monoxide, A Bibliography With Abstracts.

    ERIC Educational Resources Information Center

    Cooper, Anna Grossman

    Included is a review of the carbon monoxide related literature published from 1880 to 1966. The 983 references with abstracts are grouped into these broad categories: Analysis, Biological Effects, Blood Chemistry, Control, Criteria and Standards, Instruments and Techniques, Sampling and Network Operations, and Sources. The Biological Effects group…

  15. Development of Abstract Grammatical Categorization in Infants

    ERIC Educational Resources Information Center

    Cyr, Marilyn; Shi, Rushen

    2013-01-01

    This study examined abstract syntactic categorization in infants, using the case of grammatical gender. Ninety-six French-learning 14-, 17-, 20-, and 30-month-olds completed the study. In a preferential looking procedure infants were tested on their generalized knowledge of grammatical gender involving pseudonouns and gender-marking determiners.…

  16. Abstracts of Research Papers 1977 AAHPER Convention.

    ERIC Educational Resources Information Center

    Sage, George H., Ed.

    This volume of abstracts describes papers written on the following topics: (1) Strength Physiology; (2) Learning Disabilities (motor); (3) Physiology - General; (4) Work Capacity; (5) Measurement and Recreation; (6) Biomechanics; (7) Professional Preparation (physical education); (8) Muscle Performance; (9) Sociology of Sport; (10) History of…

  17. Spatial abstraction for autonomous robot navigation.

    PubMed

    Epstein, Susan L; Aroor, Anoop; Evanusa, Matthew; Sklar, Elizabeth I; Parsons, Simon

    2015-09-01

    Optimal navigation for a simulated robot relies on a detailed map and explicit path planning, an approach problematic for real-world robots that are subject to noise and error. This paper reports on autonomous robots that rely on local spatial perception, learning, and commonsense rationales instead. Despite realistic actuator error, learned spatial abstractions form a model that supports effective travel. PMID:26227680

  18. Natural radiation environment III. [Lead Abstract

    SciTech Connect

    Gesell, T.F.; Lowder, W.M.

    1980-01-01

    Separate abstracts were prepared for the 52 research papers presented at this symposium in April 1978. The major topics in this volume deal with penetrating radiation measurements, radiation surveys and population exposure, radioactivity in the indoor environment, and technologically enhanced natural radioactivity. (KRM)

  19. Hubble Exoplanet Pro/Am Collaboration (Abstract)

    NASA Astrophysics Data System (ADS)

    Conti, D. M.

    2016-06-01

    (Abstract only) A collaborative effort is being organized between a world-wide network of amateur astronomers and a Hubble Space Telescope (HST) science team. The purpose of this collaboration is to supplement an HST near-infrared spectroscopy survey of some 15 exoplanets with ground-based observations in the visible range.

  20. Mr. Birmingham and His New Star (Abstract)

    NASA Astrophysics Data System (ADS)

    O'Neill, J.

    2016-06-01

    (Abstract only) The year 2016 sees two anniversaries connected with the Irish astronomer John Birmingham (1816-1884): the 200th anniversary of his birth and the 150th anniversary of his discovery of the nova outburst in T Coronae Borealis.

  1. Hilson Adolescent Profile (HAP): Hilson Research Abstracts.

    ERIC Educational Resources Information Center

    Hilson Research Inc., Kew Gardens, NY.

    Abstracts and bibliographic citations are given for the following documents concerned with the use and characteristics of the Hilson Adolescent Profile (HAP): (1) "Use of the Hilson Adolescent Profile To Compare Juvenile Offenders with Junior and Senior High School Students" (R. E. Inwald and K. E. Brobst); (2) "The Effectiveness of Social Work in…

  2. Searching Social Work Abstracts: A Review.

    ERIC Educational Resources Information Center

    Mendelsohn, Henry N.

    1986-01-01

    A subject profile using 39 concepts central to the practice of social work was searched in Social Work Abstracts (SWAB), PsycINFO, ERIC, and Social SciSearch. Social work practice concepts and search strategy, search term results, journal titles searched, and source coverage and date of most recently indexed article are noted. (EJS)

  3. Heat pipe technology. A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1978-01-01

    This bibliography cites 55 publications on the theory, design, development, fabrication, and testing of heat pipes. Applications covered include solar, nuclear, and thermoelectric energy conversion. A book (in Russian) on low temperature heat pipes is included as well as abstracts when available. Indexes provided list authors, titles/keywords (permuted) and patents.

  4. Integrating model abstraction into monitoring strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed and performed to investigate the opportunities and benefits of integrating model abstraction techniques into monitoring strategies. The study focused on future applications of modeling to contingency planning and management of potential and actual contaminant release sites wi...

  5. Annual Report: Automatic Informative Abstracting and Extracting.

    ERIC Educational Resources Information Center

    Earl, L. L.; And Others

    The development of automatic indexing, abstracting, and extracting systems is investigated. Part I describes the development of tools for making syntactic and semantic distinctions of potential use in automatic indexing and extracting. One of these tools is a program for syntactic analysis (i.e., parsing) of English, the other is a dictionary of…

  6. Contextualising Numeracy: Abstract Tools at the Coalface.

    ERIC Educational Resources Information Center

    Lukin, Annabelle

    1998-01-01

    A social semiotic approach to math is necessary because of the increasing significance of abstract tools in the workplace. A case study from the coal mining industry illustrates the need to recognize mathematics as a socially constructed system and to contextualize math instruction. (SK)

  7. ANNUAL REPORT-AUTOMATIC INDEXING AND ABSTRACTING.

    ERIC Educational Resources Information Center

    Lockheed Missiles and Space Co., Palo Alto, CA. Electronic Sciences Lab.

    THE INVESTIGATION IS CONCERNED WITH THE DEVELOPMENT OF AUTOMATIC INDEXING, ABSTRACTING, AND EXTRACTING SYSTEMS. BASIC INVESTIGATIONS IN ENGLISH MORPHOLOGY, PHONETICS, AND SYNTAX ARE PURSUED AS NECESSARY MEANS TO THIS END. IN THE FIRST SECTION THE THEORY AND DESIGN OF THE "SENTENCE DICTIONARY" EXPERIMENT IN AUTOMATIC EXTRACTION IS OUTLINED. SOME OF…

  8. Does Abstracting Threaten a Sustainable Future?

    ERIC Educational Resources Information Center

    Grant, Lyle K.

    2012-01-01

    In abstraction, or conceptual behavior, people discriminate features or properties of their surroundings. This permits people to respond selectively and precisely to specialized features of their environment, which has had many benefits, including steady advances in science and technology. Within psychology, J. R. Kantor and B. F. Skinner…

  9. Static Abstractions and the Teaching of Writing.

    ERIC Educational Resources Information Center

    Connors, Robert J.

    The element of static abstractions (SAs)--any pseudoheuristic listing of derived nominals whose purpose is to define good structure in prose writing--is one of the important historical components of the current traditional rhetoric inherited from the nineteenth century. SAs, of which unity, coherence, and emphasis are the best known examples, have…

  10. Heat pipe technology: A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The annual supplement on heat pipe technology for 1971 is presented. The document contains 101 references with abstracts and 47 patents. The subjects discussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design, development, and fabrication of heat pipes, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.

  11. Conference Abstracts: Computers in Physics Instruction.

    ERIC Educational Resources Information Center

    Baird, William E.

    1989-01-01

    Provides selected abstracts from the Computers in Physics Instruction conference held on August 1-5, 1988. Topics include: wave and particle motion, the CT programing language, microcomputer-based laboratories, student written simulations, concept maps, summer institutes, computer bulletin boards, interactive video, and videodisks. (MVL)

  12. The Eggen Card Project (Poster abstract)

    NASA Astrophysics Data System (ADS)

    Silvis, G.

    2015-06-01

    (Abstract only) At the 2013 meeting we kicked off the Eggen Card project. This project was to make the huge collection of photometric observations made by Olin Eggen accessible to researchers. My poster this year is to report progress and encourage more members to participate.

  13. Coding the Eggen Cards (Poster abstract)

    NASA Astrophysics Data System (ADS)

    Silvis, G.

    2014-06-01

    (Abstract only) A look at the Eggen Portal for accessing the Eggen cards. And a call for volunteers to help code the cards: 100,000 cards must be looked at and their star references identified and coded into the database for this to be a valuable resource.

  14. Abstract Schemas in Children's Chess Cognition.

    ERIC Educational Resources Information Center

    Horgan, Dianne; And Others

    The nature and development of semantic processing in chess was investigated in a study involving younger players from 6 through 18 years of age. Efforts were directed toward establishing the assertion that skilled players' memory for chess positions depends largely upon the availability of pre-stored schema (PSS) that are both abstract and…

  15. Situated Learning in an Abstract Algebra Classroom

    ERIC Educational Resources Information Center

    Ticknor, Cindy S.

    2012-01-01

    Advisory committees of mathematics consider abstract algebra as an essential component of the mathematical preparation of secondary teachers, yet preservice teachers find it challenging to connect the topics addressed in this advanced course with the high school algebra they must someday teach. This study analyzed the mathematical content…

  16. Abstracts of Research. July 1974-June 1975.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Computer and Information Science Research Center.

    Abstracts of research papers in computer and information science are given for 68 papers in the areas of information storage and retrieval; human information processing; information analysis; linguistic analysis; artificial intelligence; information processes in physical, biological, and social systems; mathematical techniques; systems…

  17. Using Group Explorer in Teaching Abstract Algebra

    ERIC Educational Resources Information Center

    Schubert, Claus; Gfeller, Mary; Donohue, Christopher

    2013-01-01

    This study explores the use of Group Explorer in an undergraduate mathematics course in abstract algebra. The visual nature of Group Explorer in representing concepts in group theory is an attractive incentive to use this software in the classroom. However, little is known about students' perceptions on this technology in learning concepts in…

  18. Reducing Abstraction When Learning Graph Theory

    ERIC Educational Resources Information Center

    Hazzan, Orit; Hadar, Irit

    2005-01-01

    This article presents research on students' understanding of basic concepts in Graph Theory. Students' understanding is analyzed through the lens of the theoretical framework of reducing abstraction (Hazzan, 1999). As it turns out, in spite of the relative simplicity of the concepts that are introduced in the introductory part of a traditional…

  19. Searching Chemical Abstracts Online in Undergraduate Chemistry.

    ERIC Educational Resources Information Center

    Krumpolc, Miroslav; And Others

    1987-01-01

    Discusses the advantages of conducting online computer searches of "Chemical Abstracts." Introduces the logical sequences involved in searching an online database. Explains Boolean logic, proximity operators, truncation, searchable fields, and command language, as they relate to the use of online searches in undergraduate chemistry programs. (TW)

  20. Cool Cats: Feline Fun with Abstract Art.

    ERIC Educational Resources Information Center

    Lambert, Phyllis Gilchrist

    2002-01-01

    Presents a lesson that teaches students about abstract art in a fun way. Explains that students draw cats, learn about the work of Pablo Picasso, and, in the style of Picasso, combine the parts of the cats (tail, legs, head, body) together in unconventional ways. (CMK)

  1. A Photographic Assignment for Abstract Algebra

    ERIC Educational Resources Information Center

    Warrington, Gregory S.

    2009-01-01

    We describe a simple photographic assignment appropriate for an abstract algebra (or other) course. Students take digital pictures around campus of various examples of symmetry. They then classify these pictures according to which of the 17 plane symmetry groups they belong. (Contains 2 figures.)

  2. Abstract Journals: A Survey of Patent Coverage.

    ERIC Educational Resources Information Center

    Rimmer, Brenda M.

    1988-01-01

    Describes a survey of 33 British, French, German, and U.S. abstract journals that examined their coverage of patent specifications. The standards for the identification of patent documents developed by the World Intellectual Property Organization are discussed, and an appendix provides a listing of the patent coverage by the country of each…

  3. Simulation, Design Abstraction, and SystemC

    ERIC Educational Resources Information Center

    Harcourt, Ed

    2007-01-01

    SystemC is a system-level design and simulation language based on C++. We've been using SystemC for computer organization and design projects for the past several years. Because SystemC is embedded in C++ it contains the powerful abstraction mechanisms of C++ not found in traditional hardware description languages, such as support for…

  4. Abstracts of Energy Materials for College Classes.

    ERIC Educational Resources Information Center

    Messenger, Roger A.; And Others

    This guide provides citations and abstracts for 250 energy-related resources which can be used to incorporate energy education into the structure of existing college courses. In addition to citing books, articles, unpublished papers, films, and videotapes, the resource guide cites sets of class notes and course outlines that have been filed with…

  5. C. M. Louttit and "Psychological Abstracts"

    ERIC Educational Resources Information Center

    Littman, Richard A.

    2007-01-01

    R. A. Littman indicates that L. T. Benjamin and G. R. VandenBos's history of Psychological Abstracts is a fine account of how the American Psychological Association has carried out its responsibility to provide access to psychological research and writing. Littman was pleased to see Mac Louttit's work as editor brought out, and he takes this…

  6. Abstracts, Third Space Processing Symposium, Skylab results

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Skylab experiments results are reported in abstracts of papers presented at the Third Space Processing Symposium. Specific areas of interest include: exothermic brazing, metals melting, crystals, reinforced composites, glasses, eutectics; physics of the low-g processes; electrophoresis, heat flow, and convection demonstrations flown on Apollo missions; and apparatus for containerless processing, heating, cooling, and containing materials.

  7. The Child and the Abstract Expressionist.

    ERIC Educational Resources Information Center

    Henkes, Robert

    1990-01-01

    Explores the similarities between paintings of the abstract expressionists and those of young children. Similarities include total surface coverage, disregard for details, direct application of pigment, disregard for visual perspective, and use of the painting surface as a frontal plane. (CB)

  8. An Introduction to Chemical Abstracts, with Exercises.

    ERIC Educational Resources Information Center

    Robertson, Craig A.

    This workbook is the first in a series of three that has been integrated into the chemistry curriculum for majors at the University of Vermont. The workbook consists of exercises designed to provide undergraduate students with foundation skills in the use of professional literature and a familiarity with the printed "Chemical Abstracts." Each…

  9. Galerkin approximation for inverse problems for nonautonomous nonlinear distributed systems

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Reich, Simeon; Rosen, I. G.

    1988-01-01

    An abstract framework and convergence theory is developed for Galerkin approximation for inverse problems involving the identification of nonautonomous nonlinear distributed parameter systems. A set of relatively easily verified conditions is provided which are sufficient to guarantee the existence of optimal solutions and their approximation by a sequence of solutions to a sequence of approximating finite dimensional identification problems. The approach is based on the theory of monotone operators in Banach spaces and is applicable to a reasonably broad class of nonlinear distributed systems. Operator theoretic and variational techniques are used to establish a fundamental convergence result. An example involving evolution systems with dynamics described by nonstationary quasilinear elliptic operators along with some applications are presented and discussed.

  10. Background issues for defensive interceptors

    SciTech Connect

    Canavan, G.H.

    1991-03-01

    Mean nuclear backgrounds are large, but are arguably amenable to frame-to-frame subtraction. Striated backgrounds on the sensors for defensive interceptors could, however, cause clutter leak-through, which could make detection and track difficult. Nominal motions and backgrounds give signal to clutter ratios too low to be useful. Clutter leakage due to line-of-sight drift can be reduced by stabilizing the line of sight around the background clutter itself. Current interceptors have detector arrays large enough for operation independent of nuclear backgrounds in their fields of view. 6 refs., 2 figs.

  11. Columbia Basin Fish and Wildlife Authority Project Abstracts; May 25-27, Portland, Oregon, 1997 Annual Review.

    SciTech Connect

    Allee, Brian J.

    1997-06-26

    Abstracts are presented from the 1997 Columbia Basin Fish and Wildlife Program Review of Projects. The purpose was to provide information and education on the approximate 127 million dollars in Northwest electric ratepayer fish and wildlife mitigation projects funded annually.

  12. Competition between abstraction and exchange channels in H + HCN reaction: Full-dimensional quantum dynamics

    SciTech Connect

    Jiang, Bin; Guo, Hua

    2013-12-14

    Dynamics of the title reaction is investigated on an ab initio based potential energy surface using a full-dimensional quantum wave packet method within the centrifugal sudden approximation. It is shown that the reaction between H and HCN leads to both the hydrogen exchange and hydrogen abstraction channels. The exchange channel has a lower threshold and larger cross section than the abstraction channel. It also has more oscillations due apparently to quantum resonances. Both channels are affected by long-lived resonances supported by potential wells. Comparison with experimental cross sections indicates underestimation of the abstraction barrier height.

  13. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 29)

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Abstracts are provided for 115 patents and patent applications entered into the NASA scientific and technical information system during the period January 1986 through June 1986. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent application.

  14. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 30)

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Abstracts are provided for 105 patents and patent applications entered into the NASA scientific and technical information system during the period July 1986 through December 1986. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  15. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 20)

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Abstracts are cited for 165 patents and patent applications introduced into the NASA scientific and technical information system during the period July 1981 through December 1981. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  16. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 37)

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Abstracts are provided for 76 patents and patent applications entered into the NASA scientific and technical information systems during the period January 1990 through June 1990. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  17. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 38)

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Abstracts are provided for 132 patents and patent applications entered into the NASA scientific and technical information system during the period July 1990 through December 1990. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  18. Choosing a Database for Social Work: A Comparison of Social Work Abstracts and Social Service Abstracts

    ERIC Educational Resources Information Center

    Flatley, Robert K.; Lilla, Rick; Widner, Jack

    2007-01-01

    This study compared Social Work Abstracts and Social Services Abstracts databases in terms of indexing, journal coverage, and searches. The authors interviewed editors, analyzed journal coverage, and compared searches. It was determined that the databases complement one another more than compete. The authors conclude with some considerations.

  19. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 28)

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Abstracts are provided for 109 patents and patent applications entered into the NASA Scientific and Technical Information System during the period July 1985 through December 1985. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  20. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 16)

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Abstracts are cited for 138 patents and patent applications introduced into the NASA scientific and technical information system during the period July 1979 through December 1979. Each entry cib consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  1. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 14)

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Abstracts are cited for 213 patents and applications for patent introduced into the NASA scientific and technical information system during the period of July 1978 through December 1978. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent.

  2. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 19)

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Abstracts are cited for 130 patents and patent applications introduced into the NASA scientific and technical information system during the period of January 1981 through July 1981. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent.

  3. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 18)

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Abstracts are cited for 120 patents and patent applications for patents introduced into the NASA scientific system during the period of July 1980 through December 1980. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent.

  4. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 17)

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Abstracts are cited for 150 patents and applications for patents introduced into the NASA scientific and technical information system during the period January 1980 through June 1980. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent.

  5. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 15)

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Abstracts are cited for 240 patents and applications for patents introduced into the NASA scientific system during the period of January 1979 through June 1979. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent.

  6. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 33)

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Abstracts are provided for 16 patents and patent applications entered into the NASA scientific and technical information systems during the period January 1988 through June 1988. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  7. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 25)

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Abstracts are provided for 102 patents and patent applications entered into the NASA scientific and technical information system during the period January 1984 through June 1984. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  8. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 35)

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Abstracts are provided for 58 patents and patent applications entered into the NASA scientific and technical information systems during the period January 1989 through June 1989. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  9. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 24)

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Abstracts are provided for 167 patents and patent applications entered into the NASA scientific and technical information system during the period July 1983 through December 1983. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  10. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 34)

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Abstracts are provided for 124 patents and patent applications entered into the NASA scientific and technical information systems during the period July 1988 through December 1988. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  11. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 39)

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Abstracts are provided for 154 patents and patent applications entered into the NASA scientific and technical information systems during the period Jan. 1991 through Jun. 1991. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  12. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 42)

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Abstracts are provided for 174 patents and patent applications entered into the NASA scientific and technical information system during the period July 1992 through December 1992. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  13. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 36)

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Abstracts are provided for 63 patents and patent applications entered into the NASA scientific and technical information systems during the period July 1989 through December 1989. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  14. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 26)

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Abstracts are provided for 172 patents and patent applications entered into the NASA scientific and technical information system during the period July 1984 through December 1984. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  15. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 45)

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Abstracts are provided for 137 patents and patent applications entered into the NASA scientific and technical information system during the period Jan. 1994 through Jun. 1994. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  16. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 32)

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Abstracts are provided for 136 patents and patent applications entered into the NASA scientific and technical information system during the period July through December 1987. Each entry consists of a citation , an abstract, and in most cases, a key illustration selected from the patent or patent application.

  17. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 43)

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Abstracts are provided for 128 patents and patent applications entered into the NASA scientific and technical information system during the period Jan. 1993 through Jun. 1993. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  18. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 27)

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Abstracts are provided for 92 patents and patent applications entered into the NASA scientific and technical information system during the period January 1985 through June 1985. Each entry consist of a citation, and abstract, and in most cases, a key illustration selected from the patent or patent application.

  19. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 44)

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Abstracts are provided for 131 patents and patent applications entered into the NASA scientific and technical information system during the period Jun. 1993 through Dec. 1993. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  20. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 31)

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Abstracts are provided for 85 patents and patent applications entered into the NASA scientific and technical information system during the period January 1987 through June 1987. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  1. NASA Patent Abstracts Bibliography: A Continuing Bibliography. Section 1: Abstracts (Supplement 48)

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Abstracts are provided for 85 patents and patent applications entered into the NASA scientific and technical information system during the period July 1995 through December 1995. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  2. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 40)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Abstracts are provided for 181 patents and patent applications entered into the NASA scientific and technical information system during the period July 1991 through December 1991. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  3. NASA patent abstracts bibliography. A continuing bibliography (supplement 22). Section 1: Abstracts

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Abstracts are cited for 234 patents and patent applications introduced into the NASA scientific and technical information system during the period July 1982 through December 1982. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  4. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 41)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Abstracts are provided for 131 patents and patent applications entered into the NASA scientific and technical information system during the period Jan. 1992 through Jun. 1992. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  5. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 23)

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Abstracts are cited for 129 patents and patent applications introduced into the NASA scientific and technical information system during the period January 1983 through June 1983. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application.

  6. Abstraction of Drift-Scale Coupled Processes

    SciTech Connect

    N.D. Francis; D. Sassani

    2000-03-31

    This Analysis/Model Report (AMR) describes an abstraction, for the performance assessment total system model, of the near-field host rock water chemistry and gas-phase composition. It also provides an abstracted process model analysis of potentially important differences in the thermal hydrologic (TH) variables used to describe the performance of a geologic repository obtained from models that include fully coupled reactive transport with thermal hydrology and those that include thermal hydrology alone. Specifically, the motivation of the process-level model comparison between fully coupled thermal-hydrologic-chemical (THC) and thermal-hydrologic-only (TH-only) is to provide the necessary justification as to why the in-drift thermodynamic environment and the near-field host rock percolation flux, the essential TH variables used to describe the performance of a geologic repository, can be obtained using a TH-only model and applied directly into a TSPA abstraction without recourse to a fully coupled reactive transport model. Abstraction as used in the context of this AMR refers to an extraction of essential data or information from the process-level model. The abstraction analysis reproduces and bounds the results of the underlying detailed process-level model. The primary purpose of this AMR is to abstract the results of the fully-coupled, THC model (CRWMS M&O 2000a) for effects on water and gas-phase composition adjacent to the drift wall (in the near-field host rock). It is assumed that drift wall fracture water and gas compositions may enter the emplacement drift before, during, and after the heating period. The heating period includes both the preclosure, in which the repository drifts are ventilated, and the postclosure periods, with backfill and drip shield emplacement at the time of repository closure. Although the preclosure period (50 years) is included in the process models, the postclosure performance assessment starts at the end of this initial period

  7. Generalized stationary phase approximations for mountain waves

    NASA Astrophysics Data System (ADS)

    Knight, H.; Broutman, D.; Eckermann, S. D.

    2016-04-01

    Large altitude asymptotic approximations are derived for vertical displacements due to mountain waves generated by hydrostatic wind flow over arbitrary topography. This leads to new asymptotic analytic expressions for wave-induced vertical displacement for mountains with an elliptical Gaussian shape and with the major axis oriented at any angle relative to the background wind. The motivation is to understand local maxima in vertical displacement amplitude at a given height for elliptical mountains aligned at oblique angles to the wind direction, as identified in Eckermann et al. ["Effects of horizontal geometrical spreading on the parameterization of orographic gravity-wave drag. Part 1: Numerical transform solutions," J. Atmos. Sci. 72, 2330-2347 (2015)]. The standard stationary phase method reproduces one type of local amplitude maximum that migrates downwind with increasing altitude. Another type of local amplitude maximum stays close to the vertical axis over the center of the mountain, and a new generalized stationary phase method is developed to describe this other type of local amplitude maximum and the horizontal variation of wave-induced vertical displacement near the vertical axis of the mountain in the large altitude limit. The new generalized stationary phase method describes the asymptotic behavior of integrals where the asymptotic parameter is raised to two different powers (1/2 and 1) rather than just one power as in the standard stationary phase method. The vertical displacement formulas are initially derived assuming a uniform background wind but are extended to accommodate both vertical shear with a fixed wind direction and vertical variations in the buoyancy frequency.

  8. Space Electrochemical Research and Technology. Abstracts

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This document contains abstracts of the proceedings of NASA's fifth Space Electrochemical Research and Technology (SERT) Conference, held at the NASA Lewis Research Center on May 1-3, 1995. The objective of the conference was to assess the present status and general thrust of research and development in those areas of electrochemical technology required to enable NASA missions into the next century. The conference provided a forum for the exchange of ideas and opinions of those actively involved in the field, in order to define new opportunities for the application of electrochemical processes in future NASA missions. Papers were presented in three technical areas: (1) the electrochemical interface, (2) the next generation in aerospace batteries and fuel cells, and (3) electrochemistry for non-energy storage applications. This document contains the abstracts of the papers presented.

  9. Subwog 12-D tritium technology meeting. Abstracts

    SciTech Connect

    Parker, M.J.; Addis, R.P.

    1991-12-31

    The first Subwog 12-D Tritium Technology Meeting was held at the Westinghouse Savannah River Site during the week of May 21, 1990. Subwog 12-D was created as a subwog of JOWOG 12 to address the need to understand tritium applications throughout the entire weapons complex. This includes weapons related concerns, but is primarily intended to cover tritium production and handling, environmental, safety and health issues, compatibility with materials in general; and facility design, commissioning and decommissioning activities. Tritium technology issues discussed included the physical and chemical properties, kinetics, storage, reservoir loading techniques, isotope exchange, radiolysis/aging, process and handling technology, compatibility, purification and filtering, analysis, monitoring methods, function testing, packaging and shipping, environmental and operational safety, facility design and safety, glovebox atmosphere clean-up systems, glovebox/facility decommissioning, tritium production target materials, and tritium recovery. This document provides a collection of most of the unclassified extended abstracts and abstracts presented at Subwog 12-D.

  10. Automatic identification of abstract online groups

    SciTech Connect

    Engel, David W; Gregory, Michelle L; Bell, Eric B; Cowell, Andrew J; Piatt, Andrew W

    2014-04-15

    Online abstract groups, in which members aren't explicitly connected, can be automatically identified by computer-implemented methods. The methods involve harvesting records from social media and extracting content-based and structure-based features from each record. Each record includes a social-media posting and is associated with one or more entities. Each feature is stored on a data storage device and includes a computer-readable representation of an attribute of one or more records. The methods further involve grouping records into record groups according to the features of each record. Further still the methods involve calculating an n-dimensional surface representing each record group and defining an outlier as a record having feature-based distances measured from every n-dimensional surface that exceed a threshold value. Each of the n-dimensional surfaces is described by a footprint that characterizes the respective record group as an online abstract group.

  11. Using Group Explorer in teaching abstract algebra

    NASA Astrophysics Data System (ADS)

    Schubert, Claus; Gfeller, Mary; Donohue, Christopher

    2013-04-01

    This study explores the use of Group Explorer in an undergraduate mathematics course in abstract algebra. The visual nature of Group Explorer in representing concepts in group theory is an attractive incentive to use this software in the classroom. However, little is known about students' perceptions on this technology in learning concepts in abstract algebra. A total of 26 participants in an undergraduate course studying group theory were surveyed regarding their experiences using Group Explorer. Findings indicate that all participants believed that the software was beneficial to their learning and described their attitudes regarding the software in terms of using the technology and its helpfulness in learning concepts. A multiple regression analysis reveals that representational fluency of concepts with the software correlated significantly with participants' understanding of group concepts yet, participants' attitudes about Group Explorer and technology in general were not significant factors.

  12. HBCUs Research Conference agenda and abstracts

    NASA Technical Reports Server (NTRS)

    Dutta, Sunil (Compiler)

    1995-01-01

    The purpose of this Historically Black Colleges and Universities (HBCUs) Research conference was to provide an opportunity for principal investigators and their students to present research progress reports. The abstracts included in this report indicate the range and quality of research topics such as aeropropulsion, space propulsion, space power, fluid dynamics, designs, structures and materials being funded through grants from Lewis Research Center to HBCUs. The conference generated extensive networking between students, principal investigators, Lewis technical monitors, and other Lewis researchers.

  13. Cryogenic adhesives and sealants: Abstracted publications

    NASA Technical Reports Server (NTRS)

    Williamson, F. R.; Olien, N. A.

    1977-01-01

    Abstracts of primary documents containing original experimental data on the properties of adhesives and sealants at cryogenic temperatures are presented. The most important references mentioned in each document are cited. In addition, a brief annotation is given for documents considered secondary in nature, such as republications or variations of original reports, progress reports leading to final reports included as primary documents, and experimental data on adhesive properties at temperatures between about 130 K and room temperature.

  14. Hydrogen energy. A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Hydrogen Energy is a continuing bibliographic summary with abstracts of research and projections on the subject of hydrogen as a secondary fuel and as an energy carrier. This update to Hydrogen Energy cites additional references identified during the fourth quarter of 1978. It is the fourth in a 1978 quarterly series intended to provide current awareness to those interested in hydrogen energy. A series of cross indexes are included which track directly with those of the cumulative volume.

  15. Heat Pipe Technology: A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1974-01-01

    This bibliography lists 149 references with abstracts and 47 patents dealing with applications of heat pipe technology. Topics covered include: heat exchangers for heat recovery; electrical and electronic equipment cooling; temperature control of spacecraft; cryosurgery; cryogenic, cooling; nuclear reactor heat transfer; solar collectors; laser mirror cooling; laser vapor cavitites; cooling of permafrost; snow melting; thermal diodes variable conductance; artery gas venting; and venting; and gravity assisted pipes.

  16. HBCUs Research Conference Agenda and Abstracts

    NASA Technical Reports Server (NTRS)

    Dutta, Sunil (Compiler)

    1998-01-01

    The purpose of this Historically Black Colleges and Universities (HBCUs) Research Conference was to provide an opportunity for principal investigators and their students to present research progress reports. The abstracts included in this report indicate the range and quality of research topics such as aeropropulsion, space propulsion, space power, fluid dynamics, designs, structures and materials being funded through grants from Lewis Research Center to HBCUs. The conference generated extensive networking between students, principal investigators, Lewis technical monitors, and other Lewis researchers.

  17. Recombination at the DNA level. Abstracts

    SciTech Connect

    Not Available

    1984-01-01

    Abstracts of papers in the following areas are presented: (1) chromosome mechanics; (2) yeast systems; (3) mammalian homologous recombination; (4) transposons; (5) Mu; (6) plant transposons/T4 recombination; (7) topoisomerase, resolvase, and gyrase; (8) Escherichia coli general recombination; (9) recA; (10) repair; (11) eucaryotic enzymes; (12) integration and excision of bacteriophage; (13) site-specific recombination; and (14) recombination in vitro. (ACR)

  18. HBCUs Research Conference Agenda and Abstracts

    NASA Technical Reports Server (NTRS)

    Dutta, Sunil (Compiler)

    1997-01-01

    The purpose of this Historically Black Colleges and Universities (HBCUS) Research Conference was to provide an opportunity for principal investigators and their students to present research progress reports. The abstracts included in this report indicate the range and quality of research topics such as aeropropulsion, space propulsion, space power, fluid dynamics, designs, structures and materials being funded through grants from Lewis Research Center to HBCUS. The conference generated extensive networking between students, principal investigators, Lewis technical monitors, and other Lewis researchers.

  19. Mapping biological entities using the longest approximately common prefix method

    PubMed Central

    2014-01-01

    Background The significant growth in the volume of electronic biomedical data in recent decades has pointed to the need for approximate string matching algorithms that can expedite tasks such as named entity recognition, duplicate detection, terminology integration, and spelling correction. The task of source integration in the Unified Medical Language System (UMLS) requires considerable expert effort despite the presence of various computational tools. This problem warrants the search for a new method for approximate string matching and its UMLS-based evaluation. Results This paper introduces the Longest Approximately Common Prefix (LACP) method as an algorithm for approximate string matching that runs in linear time. We compare the LACP method for performance, precision and speed to nine other well-known string matching algorithms. As test data, we use two multiple-source samples from the Unified Medical Language System (UMLS) and two SNOMED Clinical Terms-based samples. In addition, we present a spell checker based on the LACP method. Conclusions The Longest Approximately Common Prefix method completes its string similarity evaluations in less time than all nine string similarity methods used for comparison. The Longest Approximately Common Prefix outperforms these nine approximate string matching methods in its Maximum F1 measure when evaluated on three out of the four datasets, and in its average precision on two of the four datasets. PMID:24928653

  20. Abstract concepts: data from a Grey parrot.

    PubMed

    Pepperberg, Irene M

    2013-02-01

    Do humans and nonhumans share the ability to form abstract concepts? Until the 1960s, many researchers questioned whether avian subjects could form categorical constructs, much less more abstract formulations, including concepts such as same-different or exact understanding of number. Although ethologists argued that nonhumans, including birds, had to have some understanding of divisions such as prey versus predator, mate versus nonmate, food versus nonfood, or basic relational concepts such as more versus less, simply in order to survive, no claims were made that these abilities reflected cognitive processes, and little formal data from psychology laboratories could initially support such claims. Researchers like Anthony Wright, however, succeeded in obtaining such data and inspired many others to pursue these topics, with the eventual result that several avian species are now considered "feathered primates" in terms of cognitive processes. Here I review research on numerical concepts in the Gray parrot (Psittacus erithacus), demonstrating that at least one subject, Alex, understood number symbols as abstract representations of real-world collections, in ways comparing favorably to those of apes and young human children. He not only understood such concepts, but also appeared to learn them in ways more similar to humans than to apes. PMID:23089384

  1. Implementing abstract multigrid or multilevel methods

    NASA Technical Reports Server (NTRS)

    Douglas, Craig C.

    1993-01-01

    Multigrid methods can be formulated as an algorithm for an abstract problem that is independent of the partial differential equation, domain, and discretization method. In such an abstract setting, problems not arising from partial differential equations can be treated. A general theory exists for linear problems. The general theory was motivated by a series of abstract solvers (Madpack). The latest version was motivated by the theory. Madpack now allows for a wide variety of iterative and direct solvers, preconditioners, and interpolation and projection schemes, including user callback ones. It allows for sparse, dense, and stencil matrices. Mildly nonlinear problems can be handled. Also, there is a fast, multigrid Poisson solver (two and three dimensions). The type of solvers and design decisions (including language, data structures, external library support, and callbacks) are discussed. Based on the author's experiences with two versions of Madpack, a better approach is proposed. This is based on a mixed language formulation (C and FORTRAN + preprocessor). Reasons for not using FORTRAN, C, or C++ (individually) are given. Implementing the proposed strategy is not difficult.

  2. On quantitative effects of RNA shape abstraction.

    PubMed

    Nebel, Markus E; Scheid, Anika

    2009-11-01

    Over the last few decades, much effort has been taken to develop approaches for identifying good predictions of RNA secondary structure. This is due to the fact that most computational prediction methods based on free energy minimization compute a number of suboptimal foldings and we have to identify the native folding among all these possible secondary structures. Using the abstract shapes approach as introduced by Giegerich et al. (Nucleic Acids Res 32(16):4843-4851, 2004), each class of similar secondary structures is represented by one shape and the native structures can be found among the top shape representatives. In this article, we derive some interesting results answering enumeration problems for abstract shapes and secondary structures of RNA. We compute precise asymptotics for the number of different shape representations of size n and for the number of different shapes showing up when abstracting from secondary structures of size n under a combinatorial point of view. A more realistic model taking primary structures into account remains an open challenge. We give some arguments why the present techniques cannot be applied in this case. PMID:19756808

  3. Language abstractions for low level optimization techniques

    NASA Astrophysics Data System (ADS)

    Dévai, Gergely; Gera, Zoltán; Kelemen, Zoltán

    2012-09-01

    In case of performance critical applications programmers are often forced to write code at a low abstraction level. This leads to programs that are hard to develop and maintain because the program text is mixed up by low level optimization tricks and is far from the algorithm it implements. Even if compilers are smart nowadays and provide the user with many automatically applied optimizations, practice shows that in some cases it is hopeless to optimize the program automatically without the programmer's knowledge. A complementary approach is to allow the programmer to fine tune the program but provide him with language features that make the optimization easier. These are language abstractions that make optimization techniques explicit without adding too much syntactic noise to the program text. This paper presents such language abstractions for two well-known optimizations: bitvectors and SIMD (Single Instruction Multiple Data). The language features are implemented in the embedded domain specific language Feldspar which is specifically tailored for digital signal processing applications. While we present these language elements as part of Feldspar, the ideas behind them are general enough to be applied in other language definition projects as well.

  4. (abstract) Geological Tour of Southwestern Mexico

    NASA Technical Reports Server (NTRS)

    Adams, Steven L.; Lang, Harold R.

    1993-01-01

    Nineteen Landsat Themic Mapper quarter scenes, coregistered at 28.5 m spatial resolution with three arc second digital topographic data, were used to create a movie, simulating a flight over the Guerrero and Mixteco terrains of southwestern Mexico. The flight path was chosen to elucidate important structural, stratigraphic, and geomorphic features. The video, available in VHS format, is a 360 second animation consisting of 10 800 total frames. The simulated velocity during three 120 second flight segments of the video is approximately 37 000 km per hour, traversing approximately 1 000 km on the ground.

  5. Diffuse Cosmic Infrared Background Radiation

    NASA Technical Reports Server (NTRS)

    Dwek, Eli

    2002-01-01

    The diffuse cosmic infrared background (CIB) consists of the cumulative radiant energy released in the processes of structure formation that have occurred since the decoupling of matter and radiation following the Big Bang. In this lecture I will review the observational data that provided the first detections and limits on the CIB, and the theoretical studies explaining the origin of this background. Finally, I will also discuss the relevance of this background to the universe as seen in high energy gamma-rays.

  6. Semiclassical approximation to supersymmetric quantum gravity

    NASA Astrophysics Data System (ADS)

    Kiefer, Claus; Lück, Tobias; Moniz, Paulo

    2005-08-01

    We develop a semiclassical approximation scheme for the constraint equations of supersymmetric canonical quantum gravity. This is achieved by a Born-Oppenheimer type of expansion, in analogy to the case of the usual Wheeler-DeWitt equation. The formalism is only consistent if the states at each order depend on the gravitino field. We recover at consecutive orders the Hamilton-Jacobi equation, the functional Schrödinger equation, and quantum gravitational correction terms to this Schrödinger equation. In particular, the following consequences are found: (i) the Hamilton-Jacobi equation and therefore the background spacetime must involve the gravitino, (ii) a (many-fingered) local time parameter has to be present on super Riem Σ (the space of all possible tetrad and gravitino fields), (iii) quantum supersymmetric gravitational corrections affect the evolution of the very early Universe. The physical meaning of these equations and results, in particular, the similarities to and differences from the pure bosonic case, are discussed.

  7. A Semantic Theory of Abstractions: A Preliminary Report

    NASA Technical Reports Server (NTRS)

    Nayak, P. Pandurang; Levy, Alon Y.; Lum, Henry, Jr. (Technical Monitor)

    1994-01-01

    In this paper we present a semantic theory of abstractions based on viewing abstractions as interpretations between theories. This theory captures important aspects of abstractions not captured in the theory of abstractions presented by Giunchiglia and Walsh. Instead of viewing abstractions as syntactic mappings, we view abstractions as a two step process: the intended domain model is first abstracted and then a set of (abstract) formulas is constructed to capture the abstracted domain model. Viewing and justifying abstractions as model level transformations is both natural and insightful. We provide a precise characterization of the abstract theory that exactly implements the intended abstraction, and show that this theory, while being axiomatizable, is not always finitely axiomatizable. A simple corollary of the latter result disproves a conjecture made by Tenenberg that if a theory is finitely axiomatizable, then predicate abstraction of that theory leads to a finitely axiomatizable theory.

  8. Breast cancer micrometastasis--a mortality abstract.

    PubMed

    Rigatti, Steven J

    2013-01-01

    This article presents an analysis of a survival study involving women with a history of breast cancer and either no nodal metastases, nodal micrometastases or nodal macrometastases, for the purpose of determining approximate life insurance ratings. In addition, a modification to the traditional method of determining the mortality rates of a comparison population is presented. PMID:24069780

  9. Producing approximate answers to database queries

    NASA Technical Reports Server (NTRS)

    Vrbsky, Susan V.; Liu, Jane W. S.

    1993-01-01

    We have designed and implemented a query processor, called APPROXIMATE, that makes approximate answers available if part of the database is unavailable or if there is not enough time to produce an exact answer. The accuracy of the approximate answers produced improves monotonically with the amount of data retrieved to produce the result. The exact answer is produced if all of the needed data are available and query processing is allowed to continue until completion. The monotone query processing algorithm of APPROXIMATE works within the standard relational algebra framework and can be implemented on a relational database system with little change to the relational architecture. We describe here the approximation semantics of APPROXIMATE that serves as the basis for meaningful approximations of both set-valued and single-valued queries. We show how APPROXIMATE is implemented to make effective use of semantic information, provided by an object-oriented view of the database, and describe the additional overhead required by APPROXIMATE.

  10. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 05)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    This bibliography is issued in two sections: Section 1 - Abstracts, and section 2 - Indexes. The abstract section cites 217 patents and applications for patent introduced into the NASA scientific and technical information system during the period of January 1974 through June 1974. Each entry consists of a citation, an abstract, and, in most cases, a key illustration selected from the patent or application for patent. The index section contains entries for 2653 patent and application for patent citations covering the period May 1969 through June 1974. The index section contains five indexes -- subject, inventor, source, number and accession number.

  11. Computerized Placement Tests: Background Readings.

    ERIC Educational Resources Information Center

    College Entrance Examination Board, Princeton, NJ.

    This document is a compilation of background readings for the user of Computerized Placement Tests (CPTs) developed by the College Board for student placement purposes. CPTs are computerized adaptive tests that test the individual abilities and backgrounds of examinees. CPTs are part of the ACCUPLACER student information management system. The…

  12. FAMILY BACKGROUND OF RURAL YOUTH.

    ERIC Educational Resources Information Center

    COPP, JAMES H.

    FAMILY BACKGROUNDS OF RURAL YOUTH ARE DISCUSSED. THE BACKGROUND PROVIDED BY THE FAMILY HAS IMPLICATIONS FOR THE ADJUSTMENT OF RURAL YOUTH IN AN URBANIZED, HIGHLY TECHNICAL SOCIETY. THE BASIC ECOLOGICAL CONDITIONS OF RURAL AREAS INFLUENCE THE RATE OF SOCIAL CHANGE, THE IMPORTANCE OF THE FAMILY AS A SOCIAL UNIT, AND THE ORIENTATION TOWARD LEGAL…

  13. Background reduction in cryogenic detectors

    SciTech Connect

    Bauer, Daniel A.; /Fermilab

    2005-04-01

    This paper discusses the background reduction and rejection strategy of the Cryogenic Dark Matter Search (CDMS) experiment. Recent measurements of background levels from CDMS II at Soudan are presented, along with estimates for future improvements in sensitivity expected for a proposed SuperCDMS experiment at SNOLAB.

  14. Lattice QCD in Background Fields

    SciTech Connect

    William Detmold, Brian Tiburzi, Andre Walker-Loud

    2009-06-01

    Electromagnetic properties of hadrons can be computed by lattice simulations of QCD in background fields. We demonstrate new techniques for the investigation of charged hadron properties in electric fields. Our current calculations employ large electric fields, motivating us to analyze chiral dynamics in strong QED backgrounds, and subsequently uncover surprising non-perturbative effects present at finite volume.

  15. Background Television and Reading Performance.

    ERIC Educational Resources Information Center

    Armstrong, G. Blake; And Others

    1991-01-01

    Tests G. Armstrong's and B. Greenberg's model of the effect of background television on cognitive performance, applied to reading comprehension and memory. Finds significant deleterious effects of background television, stronger and more consistent effects when testing immediately after reading, and more consistently negative effects resulting…

  16. Background events in microchannel plates

    NASA Technical Reports Server (NTRS)

    Siegmund, O. H. W.; Vallerga, J.; Wargelin, B.

    1988-01-01

    Measurements have been made to assess the characteristics and origins of background events in microchannel plates (MCPs). An overall background rate of about 0.4 events/sq cm persec has been achieved consistently for MCPs that have been baked and scrubbed. The temperature and gain of the MCPs are found to have no significant effect on the background rate. Detection of 1.46-MeV gamma rays from the MCP glass confirms the presence of K-40, with a concentration of 0.0007 percent, in MCP glass. It is shown that beta decay from K-40 is sufficient to cause the background rate and spectrum observed. Anticoincidence measurements indicate the the background rate caused by cosmic ray interactions is small (less than 0.016 events/sq cm per sec).

  17. The Development of Guidelines for Classifying and Writing Abstracts of Dance Research.

    ERIC Educational Resources Information Center

    Rowe, Patricia A.

    This study was developed and approved as a pilot project preliminary to the major task of abstracting, classifying and assessing approximately one thousand dance research studies. Most of these studies are university sponsored, date from 1901 to the present, and are found on library shelves or in department files as master's theses. When the major…

  18. American Dissertations on Foreign Education. A Bibliography with Abstracts. Canada: Volume 1.

    ERIC Educational Resources Information Center

    Parker, Franklin, Ed.

    This first volume focuses on various aspects of Canadian education. The bibliographic entries are arranged alphabetically according to the author's last name. A subject index is provided. Approximately one-fourth of the one hundred and seventy-one entries are abstracted, while the remaining three-fourths list only the author, the dissertation…

  19. American Dissertations on Foreign Education. A Bibliography with Abstracts. India: Volume 2.

    ERIC Educational Resources Information Center

    Parker, Franklin, Ed.

    This second volume focuses on the various aspects of education in India. One hundred and ninety-one dissertations are entered in this book and arranged alphabetically according to the author's last name. Entries range in date from the early part of the century to the mid 60's. Approximately one-third of these bibliographic entries are abstracted,…

  20. Innovation Abstracts; Volume VI (1984), Nos. 1-33 [Selected Numbers of Interest to Community Colleges].

    ERIC Educational Resources Information Center

    Roueche, Suanne D., Ed.

    1984-01-01

    "Innovation Abstracts" consists of brief, two-page write-ups issued approximately 40 times a year on topics that contribute to staff development. This compilation represents a selection from the 1984 volume of 22 numbers of special interest to community college faculty, administrators, and staff. The numbers selected are; (1) fragments of…

  1. Decoding actions at different levels of abstraction.

    PubMed

    Wurm, Moritz F; Lingnau, Angelika

    2015-05-20

    Brain regions that mediate action understanding must contain representations that are action specific and at the same time tolerate a wide range of perceptual variance. Whereas progress has been made in understanding such generalization mechanisms in the object domain, the neural mechanisms to conceptualize actions remain unknown. In particular, there is ongoing dissent between motor-centric and cognitive accounts whether premotor cortex or brain regions in closer relation to perceptual systems, i.e., lateral occipitotemporal cortex, contain neural populations with such mapping properties. To date, it is unclear to which degree action-specific representations in these brain regions generalize from concrete action instantiations to abstract action concepts. However, such information would be crucial to differentiate between motor and cognitive theories. Using ROI-based and searchlight-based fMRI multivoxel pattern decoding, we sought brain regions in human cortex that manage the balancing act between specificity and generality. We investigated a concrete level that distinguishes actions based on perceptual features (e.g., opening vs closing a specific bottle), an intermediate level that generalizes across movement kinematics and specific objects involved in the action (e.g., opening different bottles with cork or screw cap), and an abstract level that additionally generalizes across object category (e.g., opening bottles or boxes). We demonstrate that the inferior parietal and occipitotemporal cortex code actions at abstract levels whereas the premotor cortex codes actions at the concrete level only. Hence, occipitotemporal, but not premotor, regions fulfill the necessary criteria for action understanding. This result is compatible with cognitive theories but strongly undermines motor theories of action understanding. PMID:25995462

  2. Divvy Economies Based On (An Abstract) Temperature

    NASA Astrophysics Data System (ADS)

    Collins, Dennis G.

    2004-04-01

    The Leontief Input-Output economic system can provide a model for a one-parameter family of economic systems based on an abstract temperature T. In particular, given a normalized input-output matrix R and taking R= R(1), a family of economic systems R(1/T)=R(α) is developed that represents heating (T>1) and cooling (T<1) of the economy relative to T=1. .The economy for a given value of T represents the solution of a constrained maximum entropy problem.

  3. Review of progress in quantitative NDE. Abstracts

    SciTech Connect

    Not Available

    1992-09-01

    Abstracts of 386 papers and plenary presentations are included. The plenary sessions related to the national technology initiative. The other sessions covered the following NDE topics: corrosion, electromagnetic arrays, elastic wave scattering and backscattering/noise, civil structures, material properties, holography, shearography, UT wave propagation, eddy currents, coatings, signal processing, radiography, computed tomography, EM imaging, adhesive bonds, NMR, laser ultrasonics, composites, thermal, magnetic measurements, nonlinear acoustics, interface modeling and characterization, UT transducers, new techniques, joined materials, probes and systems, fatigue cracks and fracture, imaging and sizing, NDE in engineering and process control, acoustics of cracks, and sensors. An author index is included. (DLC)

  4. Solar thermal components. A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    Bozman, W. R. (Editor)

    1979-01-01

    This bibliographic series cites and abstracts literature and technical papers on components applied to solar thermal energy utilization. The quarterly volumes are divided into ten categories: material properties; flat plat collectors; concentrating collectors; thermal storage; heat pumps; coolers and heat exchangers; solar ponds and distillation; greenhouses; process pleat; and irrigation pumps. Each quarterly volume is compiled from a wide variety of data bases, report literature, technical briefs, journal articles and other traditional and non traditional sources. The Technology Application Center maintains a library containing many of the articles and publications referenced in the series.

  5. Software Security - The Dangers of Abstraction

    NASA Astrophysics Data System (ADS)

    Gollmann, Dieter

    Software insecurity can be explained as a potpourri of hacking methods, ranging from the familiar, e.g. buffer overruns, to the exotic, e.g. code insertion with Chinese characters. From such an angle software security would just be a collection of specific countermeasures. We will observe a common principle that can guide a structured presentation of software security and give guidance for future research directions: There exists a discrepancy between the abstract programming concepts used by software developers and their concrete implementation on the given execution platform. In support of this thesis, five case studies will be discussed, viz characters, integers, variables, atomic transactions, and double linked lists.

  6. The Lyncis Two for One Special (Abstract)

    NASA Astrophysics Data System (ADS)

    Joner, M.; Hintz, E.

    2015-12-01

    (Abstract only) The pulsating delta Scuti star AN Lyn and the near contact binary UU Lyn are conveniently located at high declination in the northern constellation of Lynx. These variable stars are about 15 arc minutes apart in the sky and differ in average brightness by roughly one magnitude. This combination makes it fairly straightforward to secure photometric data on both stars at the same time using a common set of comparison stars. We present observations made at the BYU West Mountain Observatory during the spring of 2015 and outline some preliminary conclusions that can be drawn about these distinctly different variable stars.

  7. Knowledge Abstraction in Chinese Chess Endgame Databases

    NASA Astrophysics Data System (ADS)

    Chen, Bo-Nian; Liu, Pangfeng; Hsu, Shun-Chin; Hsu, Tsan-Sheng

    Retrograde analysis is a well known approach to construct endgame databases. However, the size of the endgame databases are too large to be loaded into the main memory of a computer during tournaments. In this paper, a novel knowledge abstraction strategy is proposed to compress endgame databases. The goal is to obtain succinct knowledge for practical endgames. A specialized goal-oriented search method is described and applied on the important endgame KRKNMM. The method of combining a search algorithm with a small size of knowledge is used to handle endgame positions up to a limited depth, but with a high degree of correctness.

  8. Collaborations with Arne on Cataclysmic Variables (Abstract)

    NASA Astrophysics Data System (ADS)

    Szkody, P.

    2015-06-01

    (Abstract only) The start of the Sloan Digital Sky Survey in 2002 marked the beginning of a 14-year-long collaboration with Arne on the photometry of cataclysmic variables. Starting with the USNO Flagstaff station, and continuing with AAVSOnet, Arne and the AAVSO members contributed ground based followup of SDSS candidate CVs to determine their orbital periods and characteristics. In addition, many scientific studies using spacecraft observations with HST, XMM, and GALEX were enabled and improved due to their contemporaneous ground-based photometry. Some of the primary results in the 39 publications resulting from this long term collaboration will be summarized.

  9. A method for automatically abstracting visual documents

    NASA Technical Reports Server (NTRS)

    Rorvig, Mark E.

    1993-01-01

    Visual documents - motion sequences on film, video-tape, and digital recordings - constitute a major source of information for the Space Agency, as well as all other government and private sector entities. This article describes a method for automatically selecting key frames from visual documents. These frames may in turn be used to represent the total image sequence of visual documents in visual libraries, hypermedia systems, and training guides. The performance of the abstracting algorithm reduces 51 minutes of video sequences to 134 frames; a reduction of information in the range of 700:1.

  10. Generation and exploration of aggregation abstractions for scheduling and resource allocation

    NASA Technical Reports Server (NTRS)

    Lowry, Michael R.; Linden, Theodore A.

    1993-01-01

    This paper presents research on the abstraction of computational theories for scheduling and resource allocation. The paper describes both theory and methods for the automated generation of aggregation abstractions and approximations in which detailed resource allocation constraints are replaced by constraints between aggregate demand and capacity. The interaction of aggregation abstraction generation with the more thoroughly investigated abstractions of weakening operator preconditions is briefly discussed. The purpose of generating abstract theories for aggregated demand and resources includes: answering queries about aggregate properties, such as gross feasibility; reducing computational costs by using the solution of aggregate problems to guide the solution of detailed problems; facilitating reformulating theories to approximate problems for which there are efficient problem-solving methods; and reducing computational costs of scheduling by providing more opportunities for variable and value-ordering heuristics to be effective. Experiments are being developed to characterize the properties of aggregations that make them cost effective. Both abstract and concrete theories are represented in a variant of first-order predicate calculus, which is a parameterized multi-sorted logic that facilitates specification of large problems. A particular problem is conceptually represented as a set of ground sentences that is consistent with a quantified theory.

  11. Historical document image segmentation using background light intensity normalization

    NASA Astrophysics Data System (ADS)

    Shi, Zhixin; Govindaraju, Venu

    2004-12-01

    This paper presents a new document binarization algorithm for camera images of historical documents, which are especially found in The Library of Congress of the United States. The algorithm uses a background light intensity normalization algorithm to enhance an image before a local adaptive binarization algorithm is applied. The image normalization algorithm uses an adaptive linear or non-linear function to approximate the uneven background of the image due to the uneven surface of the document paper, aged color or uneven light source of the cameras for image lifting. Our algorithm adaptively captures the background of a document image with a "best fit" approximation. The document image is then normalized with respect to the approximation before a thresholding algorithm is applied. The technique works for both gray scale and color historical handwritten document images with significant improvement in readability for both human and OCR.

  12. Historical document image segmentation using background light intensity normalization

    NASA Astrophysics Data System (ADS)

    Shi, Zhixin; Govindaraju, Venu

    2005-01-01

    This paper presents a new document binarization algorithm for camera images of historical documents, which are especially found in The Library of Congress of the United States. The algorithm uses a background light intensity normalization algorithm to enhance an image before a local adaptive binarization algorithm is applied. The image normalization algorithm uses an adaptive linear or non-linear function to approximate the uneven background of the image due to the uneven surface of the document paper, aged color or uneven light source of the cameras for image lifting. Our algorithm adaptively captures the background of a document image with a "best fit" approximation. The document image is then normalized with respect to the approximation before a thresholding algorithm is applied. The technique works for both gray scale and color historical handwritten document images with significant improvement in readability for both human and OCR.

  13. An approximation technique for jet impingement flow

    SciTech Connect

    Najafi, Mahmoud; Fincher, Donald; Rahni, Taeibi; Javadi, KH.; Massah, H.

    2015-03-10

    The analytical approximate solution of a non-linear jet impingement flow model will be demonstrated. We will show that this is an improvement over the series approximation obtained via the Adomian decomposition method, which is itself, a powerful method for analysing non-linear differential equations. The results of these approximations will be compared to the Runge-Kutta approximation in order to demonstrate their validity.

  14. Comparison of two Pareto frontier approximations

    NASA Astrophysics Data System (ADS)

    Berezkin, V. E.; Lotov, A. V.

    2014-09-01

    A method for comparing two approximations to the multidimensional Pareto frontier in nonconvex nonlinear multicriteria optimization problems, namely, the inclusion functions method is described. A feature of the method is that Pareto frontier approximations are compared by computing and comparing inclusion functions that show which fraction of points of one Pareto frontier approximation is contained in the neighborhood of the Edgeworth-Pareto hull approximation for the other Pareto frontier.

  15. Background reduction in the SNO+ experiment

    SciTech Connect

    Segui, L.

    2015-08-17

    SNO+ is a large multi-purpose liquid scintillator experiment, which first aim is to detect the neutrinoless double beta decay of {sup 130}Te. It is placed at SNOLAB, at 6000 m.w.e. and it is based on the SNO infrastructure. SNO+ will contain approximately 780 tonnes of liquid scintillator, loaded with {sup 130}Te inside an acrylic vessel (AV) with an external volume of ultra pure water to reduce the external backgrounds. Light produced in the scintillator by the interaction of particles will be detected with about 9,000 photomultiplier’s. For the neutrinoless double beta decay phase, due to its the extremely low rate expected, the control, knowledge and reduction of the background is essential. Moreover, it will also benefit other phases of the experiment focused on the study of solar neutrinos, nucleon decay, geoneutrinos and supernovae. In order to reduce the internal background level, a novel purification technique for tellurium loaded scintillators has been developed by the collaboration that reduces the U/Th concentration and several cosmic-activated isotopes by at least a factor 10{sup 2} -10{sup 3} in a single pass. In addition, different rejection techniques have been developed for the remaining internal backgrounds based on Monte-Carlo simulations. In this work, the scintillator purification technique and the levels obtained with it will be discussed. Furthermore, an overview of the different backgrounds for the double-beta phase will be presented, highlighting some of the techniques developed to reject the remained decays based on their expected timing differences.

  16. MiniCLEAN surface backgrounds

    NASA Astrophysics Data System (ADS)

    Wang, Boqian; Schnee, Richard; Deap/Clean Collaboration

    2011-04-01

    MiniCLEAN is a dark matter experiment using 150kg fiducial mass of liquid cryogen (argon or neon) to search for Weakly Interacting Massive Particles (WIMPs). MiniCLEAN seeks to detect scintillation photons from WIMP-induced argon recoils. A potentially dominant background is from alpha decays on the inner surfaces of the containment vessel. Such events can mimic the prompt signal characteristic of nuclear recoils. This talk will show the expected background rates, methods of background discrimination, and their expected effectiveness.

  17. DSNF and other waste form degradation abstraction

    SciTech Connect

    Thornton, Thomas A.

    2000-12-20

    The purpose of this analysis/model report (AMR) is to select and/or abstract conservative degradation models for DOE-(US. Department of Energy) owned spent nuclear fuel (DSNF) and the immobilized ceramic plutonium (Pu) disposition waste forms for application in the proposed monitored geologic repository (MGR) postclosure Total System Performance Assessment (TSPA). Application of the degradation models abstracted herein for purposes other than TSPA should take into consideration the fact that they are, in general, very conservative. Using these models, the forward reaction rate for the mobilization of radionuclides, as solutes or colloids, away from the waste fondwater interface by contact with repository groundwater can then be calculated. This forward reaction rate generally consists of the dissolution reaction at the surface of spent nuclear fuel (SNF) in contact with water, but the degradation models, in some cases, may also include and account for the physical disintegration of the SNF matrix. The models do not, however, account for retardation, precipitation, or inhibition of the migration of the mobilized radionuclides in the engineered barrier system (EBS). These models are based on the assumption that all components of the DSNF waste form are released congruently with the degradation of the matrix.

  18. Directory of Energy Information Administration Model Abstracts

    SciTech Connect

    Not Available

    1986-07-16

    This directory partially fulfills the requirements of Section 8c, of the documentation order, which states in part that: The Office of Statistical Standards will annually publish an EIA document based on the collected abstracts and the appendices. This report contains brief statements about each model's title, acronym, purpose, and status, followed by more detailed information on characteristics, uses, and requirements. Sources for additional information are identified. All models active through March 1985 are included. The main body of this directory is an alphabetical list of all active EIA models. Appendix A identifies major EIA modeling systems and the models within these systems, and Appendix B identifies active EIA models by type (basic, auxiliary, and developing). EIA also leases models developed by proprietary software vendors. Documentation for these proprietary models is the responsibility of the companies from which they are leased. EIA has recently leased models from Chase Econometrics, Inc., Data Resources, Inc. (DRI), the Oak Ridge National Laboratory (ORNL), and Wharton Econometric Forecasting Associates (WEFA). Leased models are not abstracted here. The directory is intended for the use of energy and energy-policy analysts in the public and private sectors.

  19. Current Abstracts Nuclear Reactors and Technology

    SciTech Connect

    Bales, J.D.; Hicks, S.C.

    1993-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  20. Fractal Trigonometric Polynomials for Restricted Range Approximation

    NASA Astrophysics Data System (ADS)

    Chand, A. K. B.; Navascués, M. A.; Viswanathan, P.; Katiyar, S. K.

    2016-05-01

    One-sided approximation tackles the problem of approximation of a prescribed function by simple traditional functions such as polynomials or trigonometric functions that lie completely above or below it. In this paper, we use the concept of fractal interpolation function (FIF), precisely of fractal trigonometric polynomials, to construct one-sided uniform approximants for some classes of continuous functions.

  1. The 2nd United Kingdom Extracellular Vesicle Forum Meeting Abstracts

    PubMed Central

    Clayton, Aled; Lawson, Charlotte; Gardiner, Chris; Harrison, Paul; Carter, David

    2016-01-01

    The UK Extracellular Vesicles (UKEV) Forum meetings were born of the realization that there were a number of UK laboratories studying extracellular vesicle biology and using similar techniques but without a regular national meeting dedicated to EVs at which to share their findings. This was compounded by the fact that many of these labs were working in different fields and thus networking and sharing of ideas and best practice was sometimes difficult. The first workshop was organized in 2013 by Dr Charlotte Lawson, under the auspices of the Society for Endocrinology, led to the founding of the UKEV Forum and the organization of a British Heart Foundation sponsored 1-day conference held in London in December 2014. Although growing in size every year, the central aims of these workshops have remained the same: to provide a forum for discussion and exchange of ideas, to allow young scientists to present their data in the form of short talks and poster presentations and to discuss their work with more established scientists in the field. Here we include the presented abstracts for the 2015 1-day conference hosted by Cardiff University. This meeting was attended by approximately 130 delegates throughout the United Kingdom, but also attended by delegates from Belgium, Netherlands, France, Ireland and other nations. The day composed of plenary presentations from Prof Matthias Belting, Lund University, Sweden and Dr Guillaume van Niel, Institut Curie, Paris together with 10 short presentations from submitted abstracts. The topics covered were broad, with sessions on Mechanisms of EV production, EVs in Infection, EVs in Cancer and in Blood and Characterizing EVs in Biological fluids. This hopefully gives a reflection of the range of EV-related studies being conducted currently in the UK. There were also 33 poster presentations equally broad in subject matter. The organizers are grateful to the Life Science Research Network Wales – a Welsh government-funding scheme that

  2. Bringing genetic background into focus.

    PubMed

    Chow, Clement Y

    2016-02-01

    Researchers should embrace differences in genetic background to build richer disease models that more accurately reflect the level of variation in the human population, posits Clement Chow. PMID:26659016

  3. Background suppression in MAS NMR

    NASA Astrophysics Data System (ADS)

    White, Jeffery L.; Beck, Larry W.; Ferguson, David B.; Haw, James F.

    Pulse sequences for suppressing background signals from spinning modules used in magic-angle spinning NMR are described. These pulse sequences are based on spatially selective composite 90° pulses originally reported by Bax, which provide for no net excitation of spins outside the homogeneous region of the coil. We have achieved essentially complete suppression of background signals originating from our Vespel spinning module (which uses a free-standing coil) in both 1H and 13C spectra without notable loss in signal intensity. Successful modification of both Bloch decay and cross-polarization pulse sequences to include spatially selective pulses was essential to acquire background-free spectra for weak samples. Background suppression was also found to be particularly valuable for both T1 and T1 ϱ, relaxation measurements.

  4. On current sheet approximations in models of eruptive flares

    NASA Technical Reports Server (NTRS)

    Bungey, T. N.; Forbes, T. G.

    1994-01-01

    We consider an approximation sometimes used for current sheets in flux-rope models of eruptive flares. This approximation is based on a linear expansion of the background field in the vicinity of the current sheet, and it is valid when the length of the current sheet is small compared to the scale length of the coronal magnetic field. However, we find that flux-rope models which use this approximation predict the occurrence of an eruption due to a loss of ideal-MHD equilibrium even when the corresponding exact solution shows that no such eruption occurs. Determination of whether a loss of equilibrium exists can only be obtained by including higher order terms in the expansion of the field or by using the exact solution.

  5. Low Background Counting at LBNL

    DOE PAGESBeta

    Smith, A. R.; Thomas, K. J.; Norman, E. B.; Chan, Y. D.; Lesko, K. T.; Hurley, D. L.

    2015-03-24

    The Low Background Facility (LBF) at Lawrence Berkeley National Laboratory in Berkeley, California provides low background gamma spectroscopy services to a wide array of experiments and projects. The analysis of samples takes place within two unique facilities; locally within a carefully-constructed, low background cave and remotely at an underground location that historically has operated underground in Oroville, CA, but has recently been relocated to the Sanford Underground Research Facility (SURF) in Lead, SD. These facilities provide a variety of gamma spectroscopy services to low background experiments primarily in the form of passive material screening for primordial radioisotopes (U, Th, K)more » or common cosmogenic/anthropogenic products, as well as active screening via Neutron Activation Analysis for specific applications. The LBF also provides hosting services for general R&D testing in low background environments on the surface or underground for background testing of detector systems or similar prototyping. A general overview of the facilities, services, and sensitivities is presented. Recent activities and upgrades will also be presented, such as the completion of a 3π anticoincidence shield at the surface station and environmental monitoring of Fukushima fallout. The LBF is open to any users for counting services or collaboration on a wide variety of experiments and projects.« less

  6. Low Background Counting at LBNL

    SciTech Connect

    Smith, A. R.; Thomas, K. J.; Norman, E. B.; Chan, Y. D.; Lesko, K. T.; Hurley, D. L.

    2015-03-24

    The Low Background Facility (LBF) at Lawrence Berkeley National Laboratory in Berkeley, California provides low background gamma spectroscopy services to a wide array of experiments and projects. The analysis of samples takes place within two unique facilities; locally within a carefully-constructed, low background cave and remotely at an underground location that historically has operated underground in Oroville, CA, but has recently been relocated to the Sanford Underground Research Facility (SURF) in Lead, SD. These facilities provide a variety of gamma spectroscopy services to low background experiments primarily in the form of passive material screening for primordial radioisotopes (U, Th, K) or common cosmogenic/anthropogenic products, as well as active screening via Neutron Activation Analysis for specific applications. The LBF also provides hosting services for general R&D testing in low background environments on the surface or underground for background testing of detector systems or similar prototyping. A general overview of the facilities, services, and sensitivities is presented. Recent activities and upgrades will also be presented, such as the completion of a 3π anticoincidence shield at the surface station and environmental monitoring of Fukushima fallout. The LBF is open to any users for counting services or collaboration on a wide variety of experiments and projects.

  7. Low Background Counting at LBNL

    NASA Astrophysics Data System (ADS)

    Smith, A. R.; Thomas, K. J.; Norman, E. B.; Chan, Y. D.; Lesko, K. T.; Hurley, D. L.

    The Low Background Facility (LBF) at Lawrence Berkeley National Laboratory in Berkeley, California provides low background gamma spectroscopy services to a wide array of experiments and projects. The analysis of samples takes place within two unique facilities; locally within a carefully-constructed, low background cave and remotely at an underground location that historically has operated underground in Oroville, CA, but has recently been relocated to the Sanford Underground Research Facility (SURF) in Lead, SD. These facilities provide a variety of gamma spectroscopy services to low background experiments primarily in the form of passive material screening for primordial radioisotopes (U, Th, K) or common cosmogenic/anthropogenic products, as well as active screening via Neutron Activation Analysis for specific applications. The LBF also provides hosting services for general R&D testing in low background environments on the surface or underground for background testing of detector systems or similar prototyping. A general overview of the facilities, services, and sensitivities is presented. Recent activities and upgrades will also be presented, such as the completion of a 3π anticoincidence shield at the surface station and environmental monitoring of Fukushima fallout. The LBF is open to any users for counting services or collaboration on a wide variety of experiments and projects.

  8. Localised anti-branes in flux backgrounds

    NASA Astrophysics Data System (ADS)

    Hartnett, Gavin S.

    2015-06-01

    Solutions corresponding to finite temperature (anti)-D3 and M2 branes localised in flux backgrounds are constructed in a linear approximation. The flux backgrounds considered are toy models for the IR of the Klebanov-Strassler solution and its M-theory analogue, the Cvetič-Gibbons-Lü-Pope solution. Smooth solutions exist for either sign charge, in stark contrast with the previously considered case of smeared black branes. That the singularities of the anti-branes in the zero temperature extremal limit can be shielded behind a finite temperature horizon indicates that the singularities are physical and resolvable by string theory. As the charge of the branes grows large and negative, the flux at the horizon increases without bound and diverges in the extremal limit, which suggests a resolution via brane polarisation à la Polchinski-Strassler. It therefore appears that the anti-brane singularities do not indicate a problem with the SUSY-breaking metastable states corresponding to expanded anti-brane configurations in these backgrounds, nor with the use of these states in constructing the de Sitter landscape.

  9. Modelling abstraction licensing strategies ahead of the UK's water abstraction licensing reform

    NASA Astrophysics Data System (ADS)

    Klaar, M. J.

    2012-12-01

    Within England and Wales, river water abstractions are licensed and regulated by the Environment Agency (EA), who uses compliance with the Environmental Flow Indicator (EFI) to ascertain where abstraction may cause undesirable effects on river habitats and species. The EFI is a percentage deviation from natural flow represented using a flow duration curve. The allowable percentage deviation changes with different flows, and also changes depending on an assessment of the sensitivity of the river to changes in flow (Table 1). Within UK abstraction licensing, resource availability is expressed as a surplus or deficit of water resources in relation to the EFI, and utilises the concept of 'hands-off-flows' (HOFs) at the specified flow statistics detailed in Table 1. Use of a HOF system enables abstraction to cease at set flows, but also enables abstraction to occur at periods of time when more water is available. Compliance at low flows (Q95) is used by the EA to determine the hydrological classification and compliance with the Water Framework Directive (WFD) for identifying waterbodies where flow may be causing or contributing to a failure in good ecological status (GES; Table 2). This compliance assessment shows where the scenario flows are below the EFI and by how much, to help target measures for further investigation and assessment. Currently, the EA is reviewing the EFI methodology in order to assess whether or not it can be used within the reformed water abstraction licensing system which is being planned by the Department for Environment, Food and Rural Affairs (DEFRA) to ensure the licensing system is resilient to the challenges of climate change and population growth, while allowing abstractors to meet their water needs efficiently, and better protect the environment. In order to assess the robustness of the EFI, a simple model has been created which allows a number of abstraction, flow and licensing scenarios to be run to determine WFD compliance using the

  10. A unified approach to the Darwin approximation

    SciTech Connect

    Krause, Todd B.; Apte, A.; Morrison, P. J.

    2007-10-15

    There are two basic approaches to the Darwin approximation. The first involves solving the Maxwell equations in Coulomb gauge and then approximating the vector potential to remove retardation effects. The second approach approximates the Coulomb gauge equations themselves, then solves these exactly for the vector potential. There is no a priori reason that these should result in the same approximation. Here, the equivalence of these two approaches is investigated and a unified framework is provided in which to view the Darwin approximation. Darwin's original treatment is variational in nature, but subsequent applications of his ideas in the context of Vlasov's theory are not. We present here action principles for the Darwin approximation in the Vlasov context, and this serves as a consistency check on the use of the approximation in this setting.

  11. First LDEF Post-Retrieval Symposium abstracts

    NASA Technical Reports Server (NTRS)

    Levine, Arlene S. (Compiler)

    1991-01-01

    The LDE facility was designed to better understand the environments of space and the effects of prolonged exposure in these environments on future spacecraft. The symposium abstracts presented here are organized according to the symposium agenda into five sessions. The first session provides an overview of the LDEF, the experiments, the mission, and the natural and induced environments the spacecraft and experiments encountered during the mission. The second session presents results to date from studies to better define the environments of near-Earth space. The third session addresses studies of the effects of the space environments on spacecraft materials. The fourth session addresses studies of the effects of the space environments on spacecraft systems. And the fifth session addresses other subjects such as results of the LDEF life science and crystal growth experiments.

  12. Next generation epics interface to abstract data.

    SciTech Connect

    Hill, J. O.; Lange, R.

    2001-01-01

    The set of externally visible properties associated with process variables in the Experimental Physics and Industrial Control System (EPICS) is predefined in the EPICS base distribution and is therefore not extensible by plug-compatible applications. We believe that this approach, while practical for early versions of the system with a smaller user base, is now severely limiting expansion of the high-level application tool set for EPICS. To eliminate existing barriers, we propose a new C++ based interface to abstract containerized data. This paper describes the new interface, its application to message passing in distributed systems, its application to direct communication between tightly coupled programs co-resident in an address space, and its paramount position in an emerging role for EPICS -- the integration of dissimilar systems.

  13. eta Carinae Continues to Evolve (Abstract)

    NASA Astrophysics Data System (ADS)

    Martin, J. C.

    2015-06-01

    (Abstract only) Eta Carinae affords us a unique opportunity to study the pre-supernova evolution of the most massive stars. For at least the last half century, it has maintained a 5.5-year spectroscopic cycle that culminates with abrupt decreases in the strong stellar wind emission features. Over the last 15 years, the star has brightened at an accelerated rate and altered its spectrum, in addition to the spectroscopic cycle, indicating an ongoing change in state. We present Hubble Space Telescope spectroscopy and synthetic photometry from the most recent spectroscopic event (2014.5) that shows notable differences with past events and provides clues to the on-going evolution of the star.

  14. VEST: Abstract Vector Calculus Simplification in Mathematica

    SciTech Connect

    J. Squire, J. Burby and H. Qin

    2013-03-12

    We present a new package, VEST (Vector Einstein Summation Tools), that performs abstract vector calculus computations in Mathematica. Through the use of index notation, VEST is able to reduce scalar and vector expressions of a very general type using a systematic canonicalization procedure. In addition, utilizing properties of the Levi-Civita symbol, the program can derive types of multi-term vector identities that are not recognized by canonicalization, subsequently applying these to simplify large expressions. In a companion paper [1], we employ VEST in the automation of the calculation of Lagrangians for the single particle guiding center system in plasma physics, a computation which illustrates its ability to handle very large expressions. VEST has been designed to be simple and intuitive to use, both for basic checking of work and more involved computations. __________________________________________________

  15. Model Checking Abstract PLEXIL Programs with SMART

    NASA Technical Reports Server (NTRS)

    Siminiceanu, Radu I.

    2007-01-01

    We describe a method to automatically generate discrete-state models of abstract Plan Execution Interchange Language (PLEXIL) programs that can be analyzed using model checking tools. Starting from a high-level description of a PLEXIL program or a family of programs with common characteristics, the generator lays the framework that models the principles of program execution. The concrete parts of the program are not automatically generated, but require the modeler to introduce them by hand. As a case study, we generate models to verify properties of the PLEXIL macro constructs that are introduced as shorthand notation. After an exhaustive analysis, we conclude that the macro definitions obey the intended semantics and behave as expected, but contingently on a few specific requirements on the timing semantics of micro-steps in the concrete executive implementation.

  16. VEST: Abstract vector calculus simplification in Mathematica

    NASA Astrophysics Data System (ADS)

    Squire, J.; Burby, J.; Qin, H.

    2014-01-01

    We present a new package, VEST (Vector Einstein Summation Tools), that performs abstract vector calculus computations in Mathematica. Through the use of index notation, VEST is able to reduce three-dimensional scalar and vector expressions of a very general type to a well defined standard form. In addition, utilizing properties of the Levi-Civita symbol, the program can derive types of multi-term vector identities that are not recognized by reduction, subsequently applying these to simplify large expressions. In a companion paper Burby et al. (2013) [12], we employ VEST in the automation of the calculation of high-order Lagrangians for the single particle guiding center system in plasma physics, a computation which illustrates its ability to handle very large expressions. VEST has been designed to be simple and intuitive to use, both for basic checking of work and more involved computations.

  17. EE Cep Winks in Full Color (Abstract)

    NASA Astrophysics Data System (ADS)

    Walker, G.

    2015-06-01

    (Abstract only) We observe the long period (5.6 years) Eclipsing Binary Variable Star EE Cep during its 2014 eclipse. It was observed on every clear night from the Maria Mitchell Observatory as well as remote sites for a total of 25 nights. Each night consisted of a detailed time series in BVRI looking for short term variations for a total of >10,000 observations. The data was transformed to the Standard System. In addition, a time series was captured during the night of the eclipse. This data provides an alternate method to determine Time of Minimum than traditionally performed. The TOM varied with color. Several strong correlations are seen between colors substantiating the detection of variations on a time scale of hours. The long term light curve shows five interesting and different Phases with different characteristics.

  18. Abstraction in art with implications for perception.

    PubMed Central

    Zimmer, Robert

    2003-01-01

    The relationship between people and art is complex and intriguing. Of course, artworks are our creations; but in interesting and important ways, we are also created by our artworks. Our sense of the world is informed by the art we make and by the art we inherit and value, works that, in themselves, encode others' world views. This two-way effect is deeply rooted and art encodes and affects both a culture's ways of perceiving the world and its ways of remaking the world it perceives. The purpose of this paper is to indicate ways in which a study of abstraction in art can be used to discover insights into, to quote the call for papers for this issue, 'our perception of the world, acquired through experience' and 'the way concepts are formed and manipulated to achieve goals'. PMID:12903671

  19. Predicting free choices for abstract intentions.

    PubMed

    Soon, Chun Siong; He, Anna Hanxi; Bode, Stefan; Haynes, John-Dylan

    2013-04-01

    Unconscious neural activity has been repeatedly shown to precede and potentially even influence subsequent free decisions. However, to date, such findings have been mostly restricted to simple motor choices, and despite considerable debate, there is no evidence that the outcome of more complex free decisions can be predicted from prior brain signals. Here, we show that the outcome of a free decision to either add or subtract numbers can already be decoded from neural activity in medial prefrontal and parietal cortex 4 s before the participant reports they are consciously making their choice. These choice-predictive signals co-occurred with the so-called default mode brain activity pattern that was still dominant at the time when the choice-predictive signals occurred. Our results suggest that unconscious preparation of free choices is not restricted to motor preparation. Instead, decisions at multiple scales of abstraction evolve from the dynamics of preceding brain activity. PMID:23509300

  20. Interfacing microbiology and biotechnology. Conference abstracts

    SciTech Connect

    Maupin, Julia A.

    2001-05-19

    The Interfacing Microbiology and Biotechnology Conference was attended by over 100 faculty, post-docs, students, and research scientists from the US, Europe, and Latin America. The conference successfully stimulated communication and the dissemination of knowledge among scientists involved in basic and applied research. The focus of the conference was on microbial physiology and genetics and included sessions on C1 metabolism, archaeal metabolism, proteases and chaperones, gene arrays, and metabolic engineering. The meeting provided the setting for in-depth discussions between scientists who are internationally recognized for their research in these fields. The following objectives were met: (1) The promotion of interaction and future collaborative projects among scientists involved in basic and applied research which incorporates microbial physiology, genetics, and biochemistry; (2) the facilitation of communication of new research findings through seminars, posters, and abstracts; (3 ) the stimulation of enthusiasm and education among participants including graduate and undergraduate students.

  1. Use of Syllabic Logograms to Help Dyslexic Readers of English Visualize Abstract Words as Pictures

    ERIC Educational Resources Information Center

    Saez-Rodriguez, Alberto

    2009-01-01

    Background: Dyslexics read concrete words better than abstract ones. As a result, one of the major problems facing dyslexics is the fact that only part of the information that they require to communicate is concrete, i.e. can easily be pictured. Method: The experiment involved dyslexic third-grade, English-speaking children (8-year-olds) divided…

  2. Low Background Micromegas in CAST

    NASA Astrophysics Data System (ADS)

    Garza, J. G.; Aune, S.; Aznar, F.; Calvet, D.; Castel, J. F.; Christensen, F. E.; Dafni, T.; Davenport, M.; Decker, T.; Ferrer-Ribas, E.; Galán, J.; García, J. A.; Giomataris, I.; Hill, R. M.; Iguaz, F. J.; Irastorza, I. G.; Jakobsen, A. C.; Jourde, D.; Mirallas, H.; Ortega, I.; Papaevangelou, T.; Pivovaroff, M. J.; Ruz, J.; Tomás, A.; Vafeiadis, T.; Vogel, J. K.

    2015-11-01

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST), including technological pathfinder activities for the future International Axion Observatory (IAXO). The use of low background techniques and the application of discrimination algorithms based on the high granularity of the readout have led to background levels below 10-6 counts/keV/cm2/s, more than a factor 100 lower than the first generation of Micromegas detectors. The best levels achieved at the Canfranc Underground Laboratory (LSC) are as low as 10-7 counts/keV/cm2/s, showing good prospects for the application of this technology in IAXO. The current background model, based on underground and surface measurements, is presented, as well as the strategies to further reduce the background level. Finally, we will describe the R&D paths to achieve sub-keV energy thresholds, which could broaden the physics case of axion helioscopes.

  3. The Notion of Reducing Abstraction in Quadratic Functions

    ERIC Educational Resources Information Center

    Eraslan, Ali

    2008-01-01

    One possible approach students can cope with abstract algebra concepts is reducing abstraction. This notion occurs when learners are unable to adopt mental strategies as they deal with abstraction level of a given task. To make these concepts mentally accessible for themselves, learners unconsciously reduce the level of the abstraction of the…

  4. Gravitino condensation in fivebrane backgrounds

    NASA Astrophysics Data System (ADS)

    Kitazawa, Noriaki

    2002-04-01

    We calculate the tension of the D3-brane in the fivebrane background which is described by the exactly solvable SU(2)k×U(1) world-sheet conformal field theory with large Kač-Moody level k. The D3-brane tension is extracted from the amplitude of one closed string exchange between two parallel D3-branes, and the amplitude is calculated by utilizing the open-closed string duality. The tension of the D3-brane in the background does not coincide with the one in the flat space-time even in the flat space-time limit: k-->∞. The finite curvature effect should vanish in the flat space-time limit and only the topological effect can remain. Therefore, the deviation suggests the condensation of the gravitino and/or dilatino which has been expected in the fivebrane background as a gravitational instanton.

  5. Generation and Exploitation of Aggregation Abstractions for Scheduling and Resource Allocation

    NASA Technical Reports Server (NTRS)

    Linden, Theodore A.; Lowry, Michael R.

    1992-01-01

    Our research is investigating abstraction of computational theories for scheduling and resource allocation. These theories are represented in a variant of first order predicate calculus, parameterized multisorted logic, that facilitates specification of large problems. A particular problem is conceptually stated as a set of ground sentences that are consistent with a quantified theory. We are mainly investigating the automated generation of aggregation abstractions and approximations in which detailed resource allocation constraints are replaced by constraints between aggregate demand and capacity. We are also investigating the interaction of aggregation abstractions with the more thoroughly investigated abstractions of weakening operator preconditions. The purpose of the theories for aggregated demand/capacity is threefold: first, to answer queries about aggregate properties, such as gross feasibility; second, to reduce computational costs by using the solution of aggregate problems to guide the solution of detailed problems; and third, to facilitate reformulating theories to approximate problems for which there are efficient problem solving methods. We also describe novel methods for exploiting aggregation abstractions.

  6. The cosmic microwave background radiation

    NASA Technical Reports Server (NTRS)

    Silk, Joseph

    1992-01-01

    A review the implications of the spectrum and anisotropy of the cosmic microwave background for cosmology. Thermalization and processes generating spectral distortions are discussed. Anisotropy predictions are described and compared with observational constraints. If the evidence for large-scale power in the galaxy distribution in excess of that predicted by the cold dark matter model is vindicated, and the observed structure originated via gravitational instabilities of primordial density fluctuations, the predicted amplitude of microwave background anisotropies on angular scales of a degree and larger must be at least several parts in 10 exp 6.

  7. Background music and cognitive performance.

    PubMed

    Angel, Leslie A; Polzella, Donald J; Elvers, Greg C

    2010-06-01

    The present experiment employed standardized test batteries to assess the effects of fast-tempo music on cognitive performance among 56 male and female university students. A linguistic processing task and a spatial processing task were selected from the Criterion Task Set developed to assess verbal and nonverbal performance. Ten excerpts from Mozart's music matched for tempo were selected. Background music increased the speed of spatial processing and the accuracy of linguistic processing. The findings suggest that background music can have predictable effects on cognitive performance. PMID:20865993

  8. Detector Background at Muon Colliders

    SciTech Connect

    Mokhov, N.V.; Striganov, S.I.; /Fermilab

    2011-09-01

    Physics goals of a Muon Collider (MC) can only be reached with appropriate design of the ring, interaction region (IR), high-field superconducting magnets, machine-detector interface (MDI) and detector. Results of the most recent realistic simulation studies are presented for a 1.5-TeV MC. It is shown that appropriately designed IR and MDI with sophisticated shielding in the detector have a potential to substantially suppress the background rates in the MC detector. The main characteristics of backgrounds are studied.

  9. Exotic branes and nongeometric backgrounds.

    PubMed

    de Boer, Jan; Shigemori, Masaki

    2010-06-25

    When string or M theory is compactified to lower dimensions, the U-duality symmetry predicts so-called exotic branes whose higher-dimensional origin cannot be explained by the standard string or M-theory branes. We argue that exotic branes can be understood in higher dimensions as nongeometric backgrounds or U folds, and that they are important for the physics of systems which originally contain no exotic charges, since the supertube effect generically produces such exotic charges. We discuss the implications of exotic backgrounds for black hole microstate (non-)geometries. PMID:20867363

  10. Approximate Analysis of Semiconductor Laser Arrays

    NASA Technical Reports Server (NTRS)

    Marshall, William K.; Katz, Joseph

    1987-01-01

    Simplified equation yields useful information on gains and output patterns. Theoretical method based on approximate waveguide equation enables prediction of lateral modes of gain-guided planar array of parallel semiconductor lasers. Equation for entire array solved directly using piecewise approximation of index of refraction by simple functions without customary approximation based on coupled waveguid modes of individual lasers. Improved results yield better understanding of laser-array modes and help in development of well-behaved high-power semiconductor laser arrays.

  11. Constructive approximate interpolation by neural networks

    NASA Astrophysics Data System (ADS)

    Llanas, B.; Sainz, F. J.

    2006-04-01

    We present a type of single-hidden layer feedforward neural networks with sigmoidal nondecreasing activation function. We call them ai-nets. They can approximately interpolate, with arbitrary precision, any set of distinct data in one or several dimensions. They can uniformly approximate any continuous function of one variable and can be used for constructing uniform approximants of continuous functions of several variables. All these capabilities are based on a closed expression of the networks.

  12. Optimal discrete-time LQR problems for parabolic systems with unbounded input: Approximation and convergence

    NASA Technical Reports Server (NTRS)

    Rosen, I. G.

    1988-01-01

    An abstract approximation and convergence theory for the closed-loop solution of discrete-time linear-quadratic regulator problems for parabolic systems with unbounded input is developed. Under relatively mild stabilizability and detectability assumptions, functional analytic, operator techniques are used to demonstrate the norm convergence of Galerkin-based approximations to the optimal feedback control gains. The application of the general theory to a class of abstract boundary control systems is considered. Two examples, one involving the Neumann boundary control of a one-dimensional heat equation, and the other, the vibration control of a cantilevered viscoelastic beam via shear input at the free end, are discussed.

  13. NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 06)

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Patents and applications for patent introduced into the NASA scientific and technical information system are cited. Each entry consists of a citation, an abstract, and a key illustration selected from the patent or application for patent. The patent and application for patent citations are indexed according to subject, inventor, source, number, and accession number.

  14. Strengthening Structured Abstracts for Education Research: The Need for Claim-Based Structured Abstracts

    ERIC Educational Resources Information Center

    Kelly, Anthony E.; Yin, Robert K.

    2007-01-01

    Recent policy recommendations involving the putative primacy of randomized clinical trials in educational settings have reignited research paradigm debates. The authors of this article use the vehicle of strengthening structured journal abstracts to point out the argumentative character of all education research claims. They offer suggestions to…

  15. Piecewise linear approximation for hereditary control problems

    NASA Technical Reports Server (NTRS)

    Propst, Georg

    1990-01-01

    This paper presents finite-dimensional approximations for linear retarded functional differential equations by use of discontinuous piecewise linear functions. The approximation scheme is applied to optimal control problems, when a quadratic cost integral must be minimized subject to the controlled retarded system. It is shown that the approximate optimal feedback operators converge to the true ones both in the case where the cost integral ranges over a finite time interval, as well as in the case where it ranges over an infinite time interval. The arguments in the last case rely on the fact that the piecewise linear approximations to stable systems are stable in a uniform sense.

  16. Anthropometric approximation of body weight in unresponsive stroke patients

    PubMed Central

    Lorenz, M W; Graf, M; Henke, C; Hermans, M; Ziemann, U; Sitzer, M; Foerch, C

    2007-01-01

    Background and purpose Thrombolysis of acute ischaemic stroke is based strictly on body weight to ensure efficacy and to prevent bleeding complications. Many candidate stroke patients are unable to communicate their body weight, and there is often neither the means nor the time to weigh the patient. Instead, weight is estimated visually by the attending physician, but this is known to be inaccurate. Methods Based on a large general population sample of nearly 7000 subjects, we constructed approximation formulae for estimating body weight from simple anthropometric measurements (body height, and waist and hip circumference). These formulae were validated in a sample of 178 consecutive inpatients admitted to our stroke unit, and their accuracy was compared with the best visual estimation of two experienced physicians. Results The simplest formula gave the most accurate approximation (mean absolute difference 3.1 (2.6) kg), which was considerably better than the best visual estimation (physician 1: 6.5 (5.2) kg; physician 2: 7.4 (5.7) kg). It reduced the proportion of weight approximations mismatched by >10% from 31.5% and 40.4% (physicians 1 and 2, respectively) to 6.2% (anthropometric approximation). Only the patient's own estimation was more accurate (mean absolute difference 2.7 (2.4) kg). Conclusions By using an approximation formula based on simple anthropometric measurements (body height, and waist and hip circumference), it is possible to obtain a quick and accurate approximation of body weight. In situations where the exact weight of unresponsive patients cannot be ascertained quickly, we recommend using this approximation method rather than visual estimation. PMID:17494978

  17. Large ejecta fragments from asteroids. [Abstract only

    NASA Technical Reports Server (NTRS)

    Asphaug, E.

    1994-01-01

    The asteroid 4 Vesta, with its unique basaltic crust, remains a key mystery of planetary evolution. A localized olivine feature suggests excavation of subcrustal material in a crater or impact basin comparable in size to the planetary radius (R(sub vesta) is approximately = 280 km). Furthermore, a 'clan' of small asteroids associated with Vesta (by spectral and orbital similarities) may be ejecta from this impact 151 and direct parents of the basaltic achondrites. To escape, these smaller (about 4-7 km) asteroids had to be ejected at speeds greater than the escape velocity, v(sub esc) is approximately = 350 m/s. This evidence that large fragments were ejected at high speed from Vesta has not been reconciled with the present understanding of impact physics. Analytical spallation models predict that an impactor capable of ejecting these 'chips off Vesta' would be almost the size of Vesta! Such an impact would lead to the catastrophic disruption of both bodies. A simpler analysis is outlined, based on comparison with cratering on Mars, and it is shown that Vesta could survive an impact capable of ejecting kilometer-scale fragments at sufficient speed. To what extent does Vesta survive the formation of such a large crater? This is best addressed using a hydrocode such as SALE 2D with centroidal gravity to predict velocities subsequent to impact. The fragmentation outcome and velocity subsequent to the impact described to demonstrate that Vesta survives without large-scale disassembly or overturning of the crust. Vesta and its clan represent a valuable dataset for testing fragmentation hydrocodes such as SALE 2D and SPH 3D at planetary scales. Resolution required to directly model spallation 'chips' on a body 100 times as large is now marginally possible on modern workstations. These boundaries are important in near-surface ejection processes and in large-scale disruption leading to asteroid families and stripped cores.

  18. In defense of abstract conceptual representations.

    PubMed

    Binder, Jeffrey R

    2016-08-01

    An extensive program of research in the past 2 decades has focused on the role of modal sensory, motor, and affective brain systems in storing and retrieving concept knowledge. This focus has led in some circles to an underestimation of the need for more abstract, supramodal conceptual representations in semantic cognition. Evidence for supramodal processing comes from neuroimaging work documenting a large, well-defined cortical network that responds to meaningful stimuli regardless of modal content. The nodes in this network correspond to high-level "convergence zones" that receive broadly crossmodal input and presumably process crossmodal conjunctions. It is proposed that highly conjunctive representations are needed for several critical functions, including capturing conceptual similarity structure, enabling thematic associative relationships independent of conceptual similarity, and providing efficient "chunking" of concept representations for a range of higher order tasks that require concepts to be configured as situations. These hypothesized functions account for a wide range of neuroimaging results showing modulation of the supramodal convergence zone network by associative strength, lexicality, familiarity, imageability, frequency, and semantic compositionality. The evidence supports a hierarchical model of knowledge representation in which modal systems provide a mechanism for concept acquisition and serve to ground individual concepts in external reality, whereas broadly conjunctive, supramodal representations play an equally important role in concept association and situation knowledge. PMID:27294428

  19. Abstracts from the First Annual Scholarly Day.

    PubMed

    2015-07-01

    The Department of Medical Education at Baylor University Medical Center at Dallas hosted its first annual Scholarly Day to showcase the research efforts of medical students, residents, and fellows. Hania Wehbe-Janek, PhD, vice president for academic research integration for Baylor Scott and White Health Central Texas, shared the plenary session, "Building a Culture of Research at Academic Medical Centers: Impact on Medical Education and Recommended Practices." Stuart Black, MD, John Fordtran, MD, Ronald C. Jones, MD, Michael A. Ramsay, MD, William C. Roberts, MD, and Hania Wehbe-Janek, PhD, served as judges of the posters and the oral presentations. Winners in each category were as follows: best fellow poster, "Diet pattern and cardiovascular disease among women with type 2 diabetes mellitus," by Hyun Joon Shin, MD; best resident poster, "Oral squamous cell carcinoma: current concepts in imaging, staging, and fibular osteocutaneous free-flap reconstruction," by R. Evans Heithaus, MD; best medical student poster, "Neuromyelitis optica," by Elizabeth Coffee; and best oral presentation, "Transarterial chemoembolization with smaller beads: midterm clinical outcomes," by R. Evans Heithaus, MD. Overall, participants in the inaugural event presented more than 40 posters and six oral presentations. This article reprints a selection of the abstracts. PMID:26130877

  20. Abstracts from the First Annual Scholarly Day

    PubMed Central

    2015-01-01

    The Department of Medical Education at Baylor University Medical Center at Dallas hosted its first annual Scholarly Day to showcase the research efforts of medical students, residents, and fellows. Hania Wehbe-Janek, PhD, vice president for academic research integration for Baylor Scott and White Health Central Texas, shared the plenary session, “Building a Culture of Research at Academic Medical Centers: Impact on Medical Education and Recommended Practices.” Stuart Black, MD, John Fordtran, MD, Ronald C. Jones, MD, Michael A. Ramsay, MD, William C. Roberts, MD, and Hania Wehbe-Janek, PhD, served as judges of the posters and the oral presentations. Winners in each category were as follows: best fellow poster, “Diet pattern and cardiovascular disease among women with type 2 diabetes mellitus,” by Hyun Joon Shin, MD; best resident poster, “Oral squamous cell carcinoma: current concepts in imaging, staging, and fibular osteocutaneous free-flap reconstruction,” by R. Evans Heithaus, MD; best medical student poster, “Neuromyelitis optica,” by Elizabeth Coffee; and best oral presentation, “Transarterial chemoembolization with smaller beads: midterm clinical outcomes,” by R. Evans Heithaus, MD. Overall, participants in the inaugural event presented more than 40 posters and six oral presentations. This article reprints a selection of the abstracts. PMID:26130877

  1. Directory of Energy Information Administration model abstracts

    SciTech Connect

    Not Available

    1987-08-11

    This report contains brief statements from the model managers about each model's title, acronym, purpose, and status, followed by more detailed information on characteristics, uses, and requirements. Sources for additional information are identified. All models ''active'' through March 1987 are included. The main body of this directory is an alphabetical list of all active EIA models. Appendix A identifies major EIA modeling systems and the models within these systems, and Appendix B identifies active EIA models by type (basic, auxiliary, and developing). A basic model is one designated by the EIA Administrator as being sufficiently important to require sustained support and public scrutiny. An auxiliary model is one designated by the EIA Administrator as being used only occasionally in analyses, and therefore requires minimal levels of documentation. A developing model is one designated by the EIA Administrator as being under development and yet of sufficient interest to require a basic level of documentation at a future date. EIA also leases models developed by proprietary software vendors. Documentation for these ''proprietary'' models is the responsibility of the companies from which they are leased. EIA has recently leased models from Chase Econometrics, Inc., Data Resources, Inc. (DRI), the Oak Ridge National Laboratory (ORNL), and Wharton Econometric Forecasting Associates (WEFA). Leased models are not abstracted here. The directory is intended for the use of energy and energy-policy analysts in the public and private sectors.

  2. Types: A data abstraction package in FORTRAN

    SciTech Connect

    Youssef, S. )

    1990-08-01

    TYPES is a collection of Fortran programs which allow the creation and manipulation of abstract data objects'' without the need for a preprocessor. Each data object is assigned a type'' as it is created which implies participation in a set of characteristic operations. Available types include scalars, logicals, ordered sets, stacks, queues, sequences, trees, arrays, character strings, block text, histograms, virtual and allocatable memories. A data object may contain integers, reals, or other data objects in any combination. In addition to the type specific operations, a set of universal utilities allows for copying input/output to disk, naming, editing, displaying, user input, interactive creation, tests for equality of contents or structure, machine to machine translation or source code creation for and data object. TYPES is available on VAX/VMS, SUN 3, SPARC, DEC/Ultrix, Silicon Graphics 4D and Cray/Unicos machines. The capabilities of the package are discussed together with characteristic applications and experience in writing the GVerify package.

  3. Plans should abstractly describe intended behavior

    SciTech Connect

    Pfleger, K.; Hayes-Roth, B.

    1996-12-31

    Planning is the process of formulating a potential course of action. How courses of action (plans) produced by a planning module are represented and how they are used by execution-oriented modules of a complex agent to influence or dictate behavior are critical architectural issues. In contrast to the traditional model of plans as executable programs that dictate precise behaviors, we claim that autonomous agents inhabiting dynamic, unpredictable environments can make better use of plans that only abstractly describe their intended behavior. Such plans only influence or constrain behavior, rather than dictating it. This idea has been discussed in a variety of contexts, but it is seldom incorporated into working complex agents. Experiments involving instantiations of our Adaptive Intelligent Systems architecture in a variety of domains have demonstrated the generality and usefulness of the approach, even with our currently simple plan representation and mechanisms for plan following. The behavioral benefits include (1) robust improvisation of goal-directed behavior in response to dynamic situations, (2) ready exploitation of dynamically acquired knowledge or behavioral capabilities, and (3) adaptation based on dynamic aspects of coordinating diverse behaviors to achieve multiple goals. In addition to these run-time advantages, the approach has useful implications for the design and configuration of agents. Indeed, the core ideas of the approach are natural extensions of fundamental ideas in software engineering.

  4. Going Over to the Dark Side (Abstract)

    NASA Astrophysics Data System (ADS)

    Cowall, D.

    2015-06-01

    (Abstract only) This is the tale of my continuing journey transforming from a visual to a CCD photometrist. It is my hope that sharing my experiences will help and encourage others to consider taking the same path. It has been hard, but fun; a wonderful opportunity as a newly retired physician to expand my horizons. However, my brain did have to make the switch from Biology to Physics. The major barrier that concerned me was cost, but change itself was also a challenge. Other issues included dealing with the complexity of technical systems and a myriad of details. My solution was to be patient and think small to insure success and then build upon all those little victories. The pedagogical component of this project was critical as well. It began with a good mentor and continued via networking with other members at meetings, taking CHOICE courses, and most importantly: practice, practice, practice. Each plateau suggested many new possibilities. I think “The Force” is now with me! The adventure continues.

  5. Observational Activities at Manipur University, India (Abstract)

    NASA Astrophysics Data System (ADS)

    Singh, K. Y.; Meitei, I. A.; Singh, S. A.; Singh, R. B.

    2015-06-01

    (Abstract only) We have innovatively designed and constructed three observatories each costing a few hundred USD for housing three small Schmidt-Cassegrain type telescopes namely, Celestron CGE925, Celestron CGE1400, Meade 12-inch LX200GPS. These observatories are completely different in design and are found to be perfectly usable for doing serious work on astronomical observation and measurements. The observatory with the Celestron CGE1400 telescope has been inducted, since January 2012, as one of the observatories of the international “Orion Project” headquartered at Phoenix, Arizona, which is dedicated for photometric and spectroscopic observations of five bright variable stars of the Orion constellation namely, Betelgeuse (alpha Ori), Rigel (beta Ori), Mintaka (delta Ori), Alnilam (epsilon Ori) and Alnitak (zeta Ori). Using this observatory, we have been producing BVRI photometric data for the five stars of the Orion project. The other observatory with the Meade 12-inch LX200GPS telescope is being inducted into service for CCD photometric study of SU UMa stars in connection with implementation of a project funded by Indian Space Research Organization (ISRO). In the present paper, we would like to describe our self-built observatories, our observational facilities, the BVRI photometric data that we acquired for the Orion project, and our future plan for observation of variable stars of interest.

  6. Cultural Backgrounds and Textual Appropriation

    ERIC Educational Resources Information Center

    Shi, Ling

    2006-01-01

    This study examines interviews with 46 undergraduates to explore if participants with differing language and cultural backgrounds view plagiarism or textual appropriation primarily as a) a language problem because of a lack of words of one's own, or b) a cultural challenge as a result of either some first language (L1) cultural training to…

  7. Teacher Pensions: A Background Paper

    ERIC Educational Resources Information Center

    Hansen, Janet S.

    2008-01-01

    Pensions are an important but comparatively unexamined component of human resource policies in education. In an increasingly competitive world where employees are more mobile than ever, pension policies that were designed in the last century may be out of step with the needs of both individuals and schools. This background paper aims to foster…

  8. Low background techniques in CANDLES

    NASA Astrophysics Data System (ADS)

    Nakajima, K.; Iida, T.; Kishimoto, T.; Matsuoka, K.; Nomachi, M.; Umehara, S.; Chan, W. M.; Kakubata, H.; Li, X.; Maeda, T.; Ohata, T.; Temuge, B.; Tetsuno, K.; Trang, V. T. T.; Uehara, T.; Yoshida, S.; Morishita, K.; Ogawa, I.; Sakamoto, K.; Tamagawa, Y.; Yoshizawa, M.; Fushimi, K.; Hazama, R.; Naktani, N.; Suzuki, K.

    2015-08-01

    CANDLES is a double beta decay experiment using 48Ca in CaF2 crystals. The measurement is being performed with prototype detector (CANDLES III) for high sensitive measurement in the future. Recent status of detector improvements and background reduction techniques are described in this paper.

  9. Mathematical background of Parrondo's paradox

    NASA Astrophysics Data System (ADS)

    Behrends, Ehrhard

    2004-05-01

    Parrondo's paradox states that there are losing gambling games which, when being combined stochastically or in a suitable deterministic way, give rise to winning games. Here we investigate the probabilistic background. We show how the properties of the equilibrium distributions of the Markov chains under consideration give rise to the paradoxical behavior, and we provide methods how to find the best a priori strategies.

  10. Low background techniques in CANDLES

    SciTech Connect

    Nakajima, K. E-mail: nkyohei@u-fukui.ac.jp; Iida, T.; Matsuoka, K.; Nomachi, M.; Umehara, S.; Kishimoto, T.; Chan, W. M.; Kakubata, H.; Li, X.; Maeda, T.; Ohata, T.; Temuge, B.; Tetsuno, K.; Trang, V. T. T.; Uehara, T.; Yoshida, S.; Morishita, K.; Ogawa, I.; Sakamoto, K.; Tamagawa, Y.; and others

    2015-08-17

    CANDLES is a double beta decay experiment using {sup 48}Ca in CaF{sub 2} crystals. The measurement is being performed with prototype detector (CANDLES III) for high sensitive measurement in the future. Recent status of detector improvements and background reduction techniques are described in this paper.

  11. Teaching about Natural Background Radiation

    ERIC Educational Resources Information Center

    Al-Azmi, Darwish; Karunakara, N.; Mustapha, Amidu O.

    2013-01-01

    Ambient gamma dose rates in air were measured at different locations (indoors and outdoors) to demonstrate the ubiquitous nature of natural background radiation in the environment and to show that levels vary from one location to another, depending on the underlying geology. The effect of a lead shield on a gamma radiation field was also…

  12. Regional Background Fine Particulate Matter

    EPA Science Inventory

    A modeling system composed of the global model GEOS-Chem providing hourly lateral boundary conditions to the regional model CMAQ was used to calculate the policy relevant background level of fine particulate: matter. Simulations were performed for the full year of 2004 over the d...

  13. Ambient background particulate composition, outdoor natural background: interferents/clutter

    NASA Astrophysics Data System (ADS)

    Paterno, Dorothea

    2012-06-01

    It has proven a very difficult task to discriminate an actual BW threat from the natural occurring ambient particulate aerosol, which includes a significant fraction of particles consisting of mixed mineral and biological material. The interferent particles [clutter] (bio and non bio) concentration varies widely both by location, weather and season and diurnally. Naturally occurring background particulates are composed of fungal and bacterial spores both fragments and components, plant fragments and debris, animal fragments and debris, all of which may be associated with inert dust or combustion material. Some or all of which could also be considered to be an interferent to a biological warfare detector and cause these biodector systems to cause False Alarms by non specific BW bio detectors. I will share analysis of current long term background data sets.

  14. Metaphors are physical and abstract: ERPs to metaphorically modified nouns resemble ERPs to abstract language

    PubMed Central

    Forgács, Bálint; Bardolph, Megan D.; Amsel, Ben D.; DeLong, Katherine A.; Kutas, Marta

    2015-01-01

    Metaphorical expressions very often involve words referring to physical entities and experiences. Yet, figures of speech such as metaphors are not intended to be understood literally, word-by-word. We used event-related brain potentials (ERPs) to determine whether metaphorical expressions are processed more like physical or more like abstract expressions. To this end, novel adjective-noun word pairs were presented visually in three conditions: (1) Physical, easy to experience with the senses (e.g., “printed schedule”); (2) Abstract, difficult to experience with the senses (e.g., “conditional schedule”); and (3) novel Metaphorical, expressions with a physical adjective, but a figurative meaning (e.g., “thin schedule”). We replicated the N400 lexical concreteness effect for concrete vs. abstract adjectives. In order to increase the sensitivity of the concreteness manipulation on the expressions, we divided each condition into high and low groups according to rated concreteness. Mirroring the adjective result, we observed a N400 concreteness effect at the noun for physical expressions with high concreteness ratings vs. abstract expressions with low concreteness ratings, even though the nouns per se did not differ in lexical concreteness. Paradoxically, the N400 to nouns in the metaphorical expressions was indistinguishable from that to nouns in the literal abstract expressions, but only for the more concrete subgroup of metaphors; the N400 to the less concrete subgroup of metaphors patterned with that to nouns in the literal concrete expressions. In sum, we not only find evidence for conceptual concreteness separable from lexical concreteness but also that the processing of metaphorical expressions is not driven strictly by either lexical or conceptual concreteness. PMID:25713520

  15. Metaphors are physical and abstract: ERPs to metaphorically modified nouns resemble ERPs to abstract language.

    PubMed

    Forgács, Bálint; Bardolph, Megan D; Amsel, Ben D; DeLong, Katherine A; Kutas, Marta

    2015-01-01

    Metaphorical expressions very often involve words referring to physical entities and experiences. Yet, figures of speech such as metaphors are not intended to be understood literally, word-by-word. We used event-related brain potentials (ERPs) to determine whether metaphorical expressions are processed more like physical or more like abstract expressions. To this end, novel adjective-noun word pairs were presented visually in three conditions: (1) Physical, easy to experience with the senses (e.g., "printed schedule"); (2) Abstract, difficult to experience with the senses (e.g., "conditional schedule"); and (3) novel Metaphorical, expressions with a physical adjective, but a figurative meaning (e.g., "thin schedule"). We replicated the N400 lexical concreteness effect for concrete vs. abstract adjectives. In order to increase the sensitivity of the concreteness manipulation on the expressions, we divided each condition into high and low groups according to rated concreteness. Mirroring the adjective result, we observed a N400 concreteness effect at the noun for physical expressions with high concreteness ratings vs. abstract expressions with low concreteness ratings, even though the nouns per se did not differ in lexical concreteness. Paradoxically, the N400 to nouns in the metaphorical expressions was indistinguishable from that to nouns in the literal abstract expressions, but only for the more concrete subgroup of metaphors; the N400 to the less concrete subgroup of metaphors patterned with that to nouns in the literal concrete expressions. In sum, we not only find evidence for conceptual concreteness separable from lexical concreteness but also that the processing of metaphorical expressions is not driven strictly by either lexical or conceptual concreteness. PMID:25713520

  16. Hot Universe Background Explorer (HUBE)

    NASA Astrophysics Data System (ADS)

    Henry, R. C.; Murthy, J.; Ford, H.; Peacock, K.; Burrows, D. N.; Smith, B. W.; Bloch, J. J.

    1998-05-01

    The study of diffuse backgrounds has played an important role in the recent history of astronomy. From the microwave discovery of the 2.7 K background to the soft X-ray detection of coronal gas to the diffuse H2 emission from warm interstellar gas in our galaxy to the infrared mapping of wisps of dust at high galactic latitudes, diffuse background astronomy has provided fundamental insights into the nature of the universe. As the various regions of the electromagnetic spectrum have been explored, their diffuse backgrounds have been found to arise from the widest possible range of sources: from the local interstellar medium to the farthest reaches of the observable universe; from the wrinkled echo of the Big Bang to the million degree plasma between the stars. Most astronomers are ``point-source" astronomers, and the history of astronomy space missions is that few have been dedicated to the elucidation of the nature of the truly diffuse radiation. And yet a large fraction of the total electromagnetic energy in the universe occurs in the form of diffuse radiation. In some spectral ranges, we do not yet know the fraction of radiation that is diffuse; we are dealing with genuinely unexplored frontiers. We will describe the extraordinary science that can be obtained through a MIDEX mission that is dedicated to the exploration of the diffuse emission in the far ultraviolet and soft X-ray regions of the spectrum, where the diffuse radiation is dominated by emission from the hottest components of the interstellar medium and, perhaps, from the intergalactic medium. HUBE currently enjoys the status of being NASA's MIDEX Alternate Astrophysics Mission. We are re-proposing HUBE in the current MIDEX competition with a much broader scientific set of goals, aiming at a definitive spectroscopic survey of the diffuse background over a greatly-expanded spectral range. Our HUBE proposal effort is being supported by Ball Aerospace Corporation.

  17. Heat kernel expansion in the background field formalism

    NASA Astrophysics Data System (ADS)

    Barvinsky, Andrei O.

    2015-06-01

    Heat kernel expansion and background field formalism represent the combination of two calculational methods within the functional approach to quantum field theory. This approach implies construction of generating functionals for matrix elements and expectation values of physical observables. These are functionals of arbitrary external sources or the mean field of a generic configuration -- the background field. Exact calculation of quantum effects on a generic background is impossible. However, a special integral (proper time) representation for the Green's function of the wave operator -- the propagator of the theory -- and its expansion in the ultraviolet and infrared limits of respectively short and late proper time parameter allow one to construct approximations which are valid on generic background fields. Current progress of quantum field theory, its renormalization properties, model building in unification of fundamental physical interactions and QFT applications in high energy physics, gravitation and cosmology critically rely on efficiency of the heat kernel expansion and background field formalism.

  18. Spline approximations for nonlinear hereditary control systems

    NASA Technical Reports Server (NTRS)

    Daniel, P. L.

    1982-01-01

    A sline-based approximation scheme is discussed for optimal control problems governed by nonlinear nonautonomous delay differential equations. The approximating framework reduces the original control problem to a sequence of optimization problems governed by ordinary differential equations. Convergence proofs, which appeal directly to dissipative-type estimates for the underlying nonlinear operator, are given and numerical findings are summarized.

  19. Quirks of Stirling's Approximation

    ERIC Educational Resources Information Center

    Macrae, Roderick M.; Allgeier, Benjamin M.

    2013-01-01

    Stirling's approximation to ln "n"! is typically introduced to physical chemistry students as a step in the derivation of the statistical expression for the entropy. However, naive application of this approximation leads to incorrect conclusions. In this article, the problem is first illustrated using a familiar "toy…

  20. Taylor approximations of multidimensional linear differential systems

    NASA Astrophysics Data System (ADS)

    Lomadze, Vakhtang

    2016-06-01

    The Taylor approximations of a multidimensional linear differential system are of importance as they contain a complete information about it. It is shown that in order to construct them it is sufficient to truncate the exponential trajectories only. A computation of the Taylor approximations is provided using purely algebraic means, without requiring explicit knowledge of the trajectories.