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…
Berg, A O; Melle, I; Zuber, V; Simonsen, C; Nerhus, M; Ueland, T; Andreassen, O A; Sundet, K; Vaskinn, A
2017-01-01
Abstract thinking is important in modern understanding of neurocognitive abilities, and a symptom of thought disorder in psychosis. In patients with psychosis, we assessed if socio-developmental background influences abstract thinking, and the association with executive functioning and clinical psychosis symptoms. Participants (n = 174) had a diagnosis of psychotic or bipolar disorder, were 17-65 years, intelligence quotient (IQ) > 70, fluent in a Scandinavian language, and their full primary education in Norway. Immigrants (N = 58) were matched (1:2) with participants without a history of migration (N = 116). All participants completed a neurocognitive and clinical assessment. Socio-developmental background was operationalised as human developmental index (HDI) of country of birth, at year of birth. Structural equation modelling was used to assess the model with best fit. The model with best fit, χ 2 = 96.591, df = 33, p < .001, confirmed a significant indirect effect of HDI scores on abstract thinking through executive functioning, but not through clinical psychosis symptoms. This study found that socio-developmental background influences abstract thinking in psychosis by indirect effect through executive functioning. We should take into account socio-developmental background in the interpretation of neurocognitive performance in patients with psychosis, and prioritise cognitive remediation in treatment of immigrant patients.
NASA Astrophysics Data System (ADS)
Casadei, D.
2014-10-01
The objective Bayesian treatment of a model representing two independent Poisson processes, labelled as ``signal'' and ``background'' and both contributing additively to the total number of counted events, is considered. It is shown that the reference prior for the parameter of interest (the signal intensity) can be well approximated by the widely (ab)used flat prior only when the expected background is very high. On the other hand, a very simple approximation (the limiting form of the reference prior for perfect prior background knowledge) can be safely used over a large portion of the background parameters space. The resulting approximate reference posterior is a Gamma density whose parameters are related to the observed counts. This limiting form is simpler than the result obtained with a flat prior, with the additional advantage of representing a much closer approximation to the reference posterior in all cases. Hence such limiting prior should be considered a better default or conventional prior than the uniform prior. On the computing side, it is shown that a 2-parameter fitting function is able to reproduce extremely well the reference prior for any background prior. Thus, it can be useful in applications requiring the evaluation of the reference prior for a very large number of times.
A two-fluid approximation for calculating the cosmic microwave background anisotropies
NASA Technical Reports Server (NTRS)
Seljak, Uros
1994-01-01
We present a simplified treatment for calculating the cosmic microwave background anisotropy power spectrum in adiabatic models. It consists of solving for the evolution of a two-fluid model until the epoch of recombination and then integrating over the sources to obtain the cosmic microwave background (CMB) anisotropy power spectrum. The approximation is useful both for a physical understanding of CMB anisotropies as well as for a quantitative analysis of cosmological models. Comparison with exact calculations shows that the accuracy is typically 10%-20% over a large range of angles and cosmological models, including those with curvature and cosmological constant. Using this approximation we investigate the dependence of the CMB anisotropy on the cosmological parameters. We identify six dimensionless parameters that uniquely determine the anisotropy power spectrum within our approximation. CMB experiments on different angular scales could in principle provide information on all these parameters. In particular, mapping of the Doppler peaks would allow an independent determination of baryon mass density, matter mass density, and the Hubble constant.
Reappraising Abstract Paintings after Exposure to Background Information
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
Cooperative Educational Abstracting Service (CEAS). (Abstract Series No. 103-122, March 1972).
ERIC Educational Resources Information Center
International Bureau of Education, Geneva (Switzerland).
This document is a compilation of 20 English-language abstracts concerning various aspects of education in Switzerland, New Zealand, Chile, Poland, Argentina, Pakistan, Malaysia, Thailand, and France. The abstracts are informative in nature, each being approximately 1,500 words in length. They are based on documents submitted by each of the…
Co-operative Educational Abstracting Service (CEAS). [Abstract Series No. 1-4, 1969-1971].
ERIC Educational Resources Information Center
International Bureau of Education, Geneva (Switzerland).
This document is a compilation of 163 English-language abstracts concerning various aspects of education in Australia, Brazil, Bulgaria, Denmark, Finland, France, Hungary, Iceland, India, Israel, Japan, Mexico, Nigeria, Philippines, Thailand, UAR, U.S., USSR, and Yugoslavia. The abstracts are informative in nature and are approximately 1,500 words…
Abstracts Produced Using Computer Assistance.
ERIC Educational Resources Information Center
Craven, Timothy C.
2000-01-01
Describes an experiment that evaluated features of TEXNET abstracting software, compared the use of keywords and phrases that were automatically extracted, tested hypotheses about relations between abstractors' backgrounds and their reactions to abstracting assistance software, and obtained ideas for further features to be developed in TEXNET.…
Approximate Genealogies Under Genetic Hitchhiking
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
Background magnetic spectra - Approximately 10 to the -5th to approximately 10 to the 5th Hz
NASA Astrophysics Data System (ADS)
Lanzerotti, L. J.; Maclennan, C. G.; Fraser-Smith, A. C.
1990-09-01
The determination of the amplitude and functional form of the geomagnetic fluctuations measured at the Arrival Heights area of the Hut Point Peninsula on Ross Island in June 1986 is presented. The frequency range covered is from approximately 10 to the -5th to approximately 10 to the 5th Hz, with a gap between 0.1 and 10 Hz due to instrumentation limitations. In spite of this gap, it is thought that these magnetic fluctuation spectra, obtained from data acquired simultaneously with two instruments, cover the broadest frequency range to date. Schematic spectra derived from the data obtained are provided.
Newborn infants perceive abstract numbers
Izard, Véronique; Sann, Coralie; Spelke, Elizabeth S.; Streri, Arlette
2009-01-01
Although infants and animals respond to the approximate number of elements in visual, auditory, and tactile arrays, only human children and adults have been shown to possess abstract numerical representations that apply to entities of all kinds (e.g., 7 samurai, seas, or sins). Do abstract numerical concepts depend on language or culture, or do they form a part of humans' innate, core knowledge? Here we show that newborn infants spontaneously associate stationary, visual-spatial arrays of 4–18 objects with auditory sequences of events on the basis of number. Their performance provides evidence for abstract numerical representations at the start of postnatal experience. PMID:19520833
A Shallow Underground Laboratory for Low-Background Radiation Measurements and Materials Development
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aalseth, Craig E.; Bonicalzi, Ricco; Cantaloub, Michael G.
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. Wemore » conclude by presenting measurement targets and future opportunities.« less
Background characterization of an ultra-low background liquid scintillation counter
Erchinger, J. L.; Orrell, John L.; Aalseth, C. E.; ...
2017-01-26
The Ultra-Low Background Liquid Scintillation Counter developed by Pacific Northwest National Laboratory will expand the application of liquid scintillation counting by enabling lower detection limits and smaller sample volumes. By reducing the overall count rate of the background environment approximately 2 orders of magnitude below that of commercially available systems, backgrounds on the order of tens of counts per day over an energy range of ~3–3600 keV can be realized. Finally, initial test results of the ULB LSC show promising results for ultra-low background detection with liquid scintillation counting.
Abstraction in perceptual symbol systems.
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
Fostering Formal Commutativity Knowledge with Approximate Arithmetic
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
Clarifying the abstracts of systematic literature reviews*
Hartley, James
2000-01-01
Background: There is a small body of research on improving the clarity of abstracts in general that is relevant to improving the clarity of abstracts of systematic reviews. Objectives: To summarize this earlier research and indicate its implications for writing the abstracts of systematic reviews. Method: Literature review with commentary on three main features affecting the clarity of abstracts: their language, structure, and typographical presentation. Conclusions: The abstracts of systematic reviews should be easier to read than the abstracts of medical research articles, as they are targeted at a wider audience. The aims, methods, results, and conclusions of systematic reviews need to be presented in a consistent way to help search and retrieval. The typographic detailing of the abstracts (type-sizes, spacing, and weights) should be planned to help, rather than confuse, the reader. PMID:11055300
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.
Paper and Symposia Abstracts, 1972 Annual Meeting.
ERIC Educational Resources Information Center
Cunningham, Donald J., Ed.
This compendium contains abstracts of approximately 700 papers which are classified under administration, curriculum and objectives, instruction and learning, measurement and research methodology, counseling and human development, history and historiography, social context of education, school evaluation and program development, or special…
NASA Astrophysics Data System (ADS)
Pan, Zhen; Anderes, Ethan; Knox, Lloyd
2018-05-01
One of the major targets for next-generation cosmic microwave background (CMB) experiments is the detection of the primordial B-mode signal. Planning is under way for Stage-IV experiments that are projected to have instrumental noise small enough to make lensing and foregrounds the dominant source of uncertainty for estimating the tensor-to-scalar ratio r from polarization maps. This makes delensing a crucial part of future CMB polarization science. In this paper we present a likelihood method for estimating the tensor-to-scalar ratio r from CMB polarization observations, which combines the benefits of a full-scale likelihood approach with the tractability of the quadratic delensing technique. This method is a pixel space, all order likelihood analysis of the quadratic delensed B modes, and it essentially builds upon the quadratic delenser by taking into account all order lensing and pixel space anomalies. Its tractability relies on a crucial factorization of the pixel space covariance matrix of the polarization observations which allows one to compute the full Gaussian approximate likelihood profile, as a function of r , at the same computational cost of a single likelihood evaluation.
Finite dimensional approximation of a class of constrained nonlinear optimal control problems
NASA Technical Reports Server (NTRS)
Gunzburger, Max D.; Hou, L. S.
1994-01-01
An abstract framework for the analysis and approximation of a class of nonlinear optimal control and optimization problems is constructed. Nonlinearities occur in both the objective functional and in the constraints. The framework includes an abstract nonlinear optimization problem posed on infinite dimensional spaces, and approximate problem posed on finite dimensional spaces, together with a number of hypotheses concerning the two problems. The framework is used to show that optimal solutions exist, to show that Lagrange multipliers may be used to enforce the constraints, to derive an optimality system from which optimal states and controls may be deduced, and to derive existence results and error estimates for solutions of the approximate problem. The abstract framework and the results derived from that framework are then applied to three concrete control or optimization problems and their approximation by finite element methods. The first involves the von Karman plate equations of nonlinear elasticity, the second, the Ginzburg-Landau equations of superconductivity, and the third, the Navier-Stokes equations for incompressible, viscous flows.
NASA Technical Reports Server (NTRS)
Mason, B. S.; Pearson, T. J.; Readhead, A. C. S.; Shepherd, M. C.; Sievers, J.; Udomprasert, P. S.; Cartwright, J. K.; Farmer, A. J.; Padin, S.; Myers, S. T.;
2002-01-01
We report measurements of anisotropy in the cosmic microwave background radiation over the multipole range l approximately 200 (right arrow) 3500 with the Cosmic Background Imager based on deep observations of three fields. These results confirm the drop in power with increasing l first reported in earlier measurements with this instrument, and extend the observations of this decline in power out to l approximately 2000. The decline in power is consistent with the predicted damping of primary anisotropies. At larger multipoles, l = 2000-3500, the power is 3.1 sigma greater than standard models for intrinsic microwave background anisotropy in this multipole range, and 3.5 sigma greater than zero. This excess power is not consistent with expected levels of residual radio source contamination but, for sigma 8 is approximately greater than 1, is consistent with predicted levels due to a secondary Sunyaev-Zeldovich anisotropy. Further observations are necessary to confirm the level of this excess and, if confirmed, determine its origin.
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.
Students' Abstraction in Recognizing, Building with and Constructing a Quadrilateral
ERIC Educational Resources Information Center
Budiarto, Mega Teguh; Rahaju, Endah Budi; Hartono, Sugi
2017-01-01
This study aims to implement empirically students' abstraction with socio-cultural background of Indonesia. Abstraction is an activity that involves a vertical reorganization of previously constructed mathematics into a new mathematical structure. The principal components of the model are three dynamic nested epistemic actions: recognizing,…
Fundamentals and Recent Developments in Approximate Bayesian Computation
Lintusaari, Jarno; Gutmann, Michael U.; Dutta, Ritabrata; Kaski, Samuel; Corander, Jukka
2017-01-01
Abstract Bayesian inference plays an important role in phylogenetics, evolutionary biology, and in many other branches of science. It provides a principled framework for dealing with uncertainty and quantifying how it changes in the light of new evidence. For many complex models and inference problems, however, only approximate quantitative answers are obtainable. Approximate Bayesian computation (ABC) refers to a family of algorithms for approximate inference that makes a minimal set of assumptions by only requiring that sampling from a model is possible. We explain here the fundamentals of ABC, review the classical algorithms, and highlight recent developments. [ABC; approximate Bayesian computation; Bayesian inference; likelihood-free inference; phylogenetics; simulator-based models; stochastic simulation models; tree-based models.] PMID:28175922
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.;
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").
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.
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.
Approximation Algorithms for Multicommodity Flow and Shop Scheduling Problems
1992-09-01
DARPA N00014-89-J-1988 11. SUPPLEMENTARY NOTES Ŗa. oIs7RIBU ric.c / AVAILAaILITY STATEMENT, 1.2. 3ISTRIBUT;CN C:. E In this thesis , we give efficient...University Thesis Supervisor Accepted by Campbell L. Searle Chairman, Departmental Committee on Graduate Students Approximation Algorithms for Multicommodity...partial fulfillment of the requirements for the degree of Doctor of Philosophy Abstract In this thesis , we give efficient approximation algorithms for
Nuclear medicine. Bibliography from Nuclear Science Abstracts, Volumes 31--33
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1976-12-01
References to 4362 publications related to nuclear medicine announced in Nuclear Science Abstracts (NSA) volumes 31(Jan.--June 1975), 32(July--Dec. 1975), and 33(Jan.--June 1976) are contained in this bibliography. References are arranged in order by the original NSA abstract number which approximately places them in chronological order. Sequence numbers appear beside each reference, and the indexes refer to these sequence numbers. Indexes included are: Corporate, Personal Author, Subject, and Report Number.
COSMIC MICROWAVE BACKGROUND LIKELIHOOD APPROXIMATION FOR BANDED PROBABILITY DISTRIBUTIONS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gjerløw, E.; Mikkelsen, K.; Eriksen, H. K.
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 expressionmore » 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.« less
Analytical approximations to the Hotelling trace for digital x-ray detectors
NASA Astrophysics Data System (ADS)
Clarkson, Eric; Pineda, Angel R.; Barrett, Harrison H.
2001-06-01
The Hotelling trace is the signal-to-noise ratio for the ideal linear observer in a detection task. We provide an analytical approximation for this figure of merit when the signal is known exactly and the background is generated by a stationary random process, and the imaging system is an ideal digital x-ray detector. This approximation is based on assuming that the detector is infinite in extent. We test this approximation for finite-size detectors by comparing it to exact calculations using matrix inversion of the data covariance matrix. After verifying the validity of the approximation under a variety of circumstances, we use it to generate plots of the Hotelling trace as a function of pairs of parameters of the system, the signal and the background.
Refining a taxonomy for guideline implementation: results of an exercise in abstract classification
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
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,…
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,…
Background Selection in Partially Selfing Populations
Roze, Denis
2016-01-01
Self-fertilizing species often present lower levels of neutral polymorphism than their outcrossing relatives. Indeed, selfing automatically increases the rate of coalescence per generation, but also enhances the effects of background selection and genetic hitchhiking by reducing the efficiency of recombination. Approximations for the effect of background selection in partially selfing populations have been derived previously, assuming tight linkage between deleterious alleles and neutral loci. However, loosely linked deleterious mutations may have important effects on neutral diversity in highly selfing populations. In this article, I use a general method based on multilocus population genetics theory to express the effect of a deleterious allele on diversity at a linked neutral locus in terms of moments of genetic associations between loci. Expressions for these genetic moments at equilibrium are then computed for arbitrary rates of selfing and recombination. An extrapolation of the results to the case where deleterious alleles segregate at multiple loci is checked using individual-based simulations. At high selfing rates, the tight linkage approximation underestimates the effect of background selection in genomes with moderate to high map length; however, another simple approximation can be obtained for this situation and provides accurate predictions as long as the deleterious mutation rate is not too high. PMID:27075726
On Hilbert-Schmidt norm convergence of Galerkin approximation for operator Riccati equations
NASA Technical Reports Server (NTRS)
Rosen, I. G.
1988-01-01
An abstract approximation framework for the solution of operator algebraic Riccati equations is developed. The approach taken is based on a formulation of the Riccati equation as an abstract nonlinear operator equation on the space of Hilbert-Schmidt operators. Hilbert-Schmidt norm convergence of solutions to generic finite dimensional Galerkin approximations to the Riccati equation to the solution of the original infinite dimensional problem is argued. The application of the general theory is illustrated via an operator Riccati equation arising in the linear-quadratic design of an optimal feedback control law for a 1-D heat/diffusion equation. Numerical results demonstrating the convergence of the associated Hilbert-Schmidt kernels are included.
Development and evaluation of a quality score for abstracts
Timmer, Antje; Sutherland, Lloyd R; Hilsden, Robert J
2003-01-01
Background The evaluation of abstracts for scientific meetings has been shown to suffer from poor inter observer reliability. A measure was developed to assess the formal quality of abstract submissions in a standardized way. Methods Item selection was based on scoring systems for full reports, taking into account published guidelines for structured abstracts. Interrater agreement was examined using a random sample of submissions to the American Gastroenterological Association, stratified for research type (n = 100, 1992–1995). For construct validity, the association of formal quality with acceptance for presentation was examined. A questionnaire to expert reviewers evaluated sensibility items, such as ease of use and comprehensiveness. Results The index comprised 19 items. The summary quality scores showed good interrater agreement (intra class coefficient 0.60 – 0.81). Good abstract quality was associated with abstract acceptance for presentation at the meeting. The instrument was found to be acceptable by expert reviewers. Conclusion A quality index was developed for the evaluation of scientific meeting abstracts which was shown to be reliable, valid and useful. PMID:12581457
Generative electronic background music system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mazurowski, Lukasz
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.
Random-Phase Approximation Methods
NASA Astrophysics Data System (ADS)
Chen, Guo P.; Voora, Vamsee K.; Agee, Matthew M.; Balasubramani, Sree Ganesh; Furche, Filipp
2017-05-01
Random-phase approximation (RPA) methods are rapidly emerging as cost-effective validation tools for semilocal density functional computations. We present the theoretical background of RPA in an intuitive rather than formal fashion, focusing on the physical picture of screening and simple diagrammatic analysis. A new decomposition of the RPA correlation energy into plasmonic modes leads to an appealing visualization of electron correlation in terms of charge density fluctuations. Recent developments in the areas of beyond-RPA methods, RPA correlation potentials, and efficient algorithms for RPA energy and property calculations are reviewed. The ability of RPA to approximately capture static correlation in molecules is quantified by an analysis of RPA natural occupation numbers. We illustrate the use of RPA methods in applications to small-gap systems such as open-shell d- and f-element compounds, radicals, and weakly bound complexes, where semilocal density functional results exhibit strong functional dependence.
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…
Parameter estimation in nonlinear distributed systems - Approximation theory and convergence results
NASA Technical Reports Server (NTRS)
Banks, H. T.; Reich, Simeon; Rosen, I. G.
1988-01-01
An abstract approximation framework and convergence theory is described for Galerkin approximations applied to inverse problems involving nonlinear distributed parameter systems. Parameter estimation problems are considered and formulated as the minimization of a least-squares-like performance index over a compact admissible parameter set subject to state constraints given by an inhomogeneous nonlinear distributed system. The theory applies to systems whose dynamics can be described by either time-independent or nonstationary strongly maximal monotonic operators defined on a reflexive Banach space which is densely and continuously embedded in a Hilbert space. It is demonstrated that if readily verifiable conditions on the system's dependence on the unknown parameters are satisfied, and the usual Galerkin approximation assumption holds, then solutions to the approximating problems exist and approximate a solution to the original infinite-dimensional identification problem.
ERIC Educational Resources Information Center
Budiarto, Mega Teguh; Khabibah, Siti; Setianingsih, Rini
2017-01-01
The purpose of this study was to examine the abstraction thinking or the vertical reorganization activity of mathematical concepts of high school students while taking account of the abstraction that was constructed earlier, and the socio-cultural background. This study was qualitative in nature with task-based interviews as the method of…
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.
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.
Blindness to background: an inbuilt bias for visual objects.
O'Hanlon, Catherine G; Read, Jenny C A
2017-09-01
Sixty-eight 2- to 12-year-olds and 30 adults were shown colorful displays on a touchscreen monitor and trained to point to the location of a named color. Participants located targets near-perfectly when presented with four abutting colored patches. When presented with three colored patches on a colored background, toddlers failed to locate targets in the background. Eye tracking demonstrated that the effect was partially mediated by a tendency not to fixate the background. However, the effect was abolished when the targets were named as nouns, whilst the change to nouns had little impact on eye movement patterns. Our results imply a powerful, inbuilt tendency to attend to objects, which may slow the development of color concepts and acquisition of color words. A video abstract of this article can be viewed at: https://youtu.be/TKO1BPeAiOI. [Correction added on 27 January 2017, after first online publication: The video abstract link was added.]. © 2016 John Wiley & Sons Ltd.
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.
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.
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.
On the proper use of the reduced speed of light approximation
Gnedin, Nickolay Y.
2016-12-07
I show that the Reduced Speed of Light (RSL) approximation, when used properly (i.e. as originally designed - only for the local sources but not for the cosmic background), remains a highly accurate numerical method for modeling cosmic reionization. Simulated ionization and star formation histories from the "Cosmic Reionization On Computers" (CROC) project are insensitive to the adopted value of the reduced speed of light for as long as that value does not fall below about 10% of the true speed of light. Here, a recent claim of the failure of the RSL approximation in the Illustris reionization model appearsmore » to be due to the effective speed of light being reduced in the equation for the cosmic background too, and, hence, illustrates the importance of maintaining the correct speed of light in modeling the cosmic background.« less
ON THE PROPER USE OF THE REDUCED SPEED OF LIGHT APPROXIMATION
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gnedin, Nickolay Y., E-mail: gnedin@fnal.gov
I show that the reduced speed of light (RSL) approximation, when used properly (i.e., as originally designed—only for local sources but not for the cosmic background), remains a highly accurate numerical method for modeling cosmic reionization. Simulated ionization and star formation histories from the “Cosmic Reionization on Computers” project are insensitive to the adopted value of the RSL for as long as that value does not fall below about 10% of the true speed of light. A recent claim of the failure of the RSL approximation in the Illustris reionization model appears to be due to the effective speed ofmore » light being reduced in the equation for the cosmic background too and hence illustrates the importance of maintaining the correct speed of light in modeling the cosmic background.« less
On the proper use of the reduced speed of light approximation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gnedin, Nickolay Y.
I show that the Reduced Speed of Light (RSL) approximation, when used properly (i.e. as originally designed - only for the local sources but not for the cosmic background), remains a highly accurate numerical method for modeling cosmic reionization. Simulated ionization and star formation histories from the "Cosmic Reionization On Computers" (CROC) project are insensitive to the adopted value of the reduced speed of light for as long as that value does not fall below about 10% of the true speed of light. Here, a recent claim of the failure of the RSL approximation in the Illustris reionization model appearsmore » to be due to the effective speed of light being reduced in the equation for the cosmic background too, and, hence, illustrates the importance of maintaining the correct speed of light in modeling the cosmic background.« less
Dual-tracer background subtraction approach for fluorescent molecular tomography
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
On Born approximation in black hole scattering
NASA Astrophysics Data System (ADS)
Batic, D.; Kelkar, N. G.; Nowakowski, M.
2011-12-01
A massless field propagating on spherically symmetric black hole metrics such as the Schwarzschild, Reissner-Nordström and Reissner-Nordström-de Sitter backgrounds is considered. In particular, explicit formulae in terms of transcendental functions for the scattering of massless scalar particles off black holes are derived within a Born approximation. It is shown that the conditions on the existence of the Born integral forbid a straightforward extraction of the quasi normal modes using the Born approximation for the scattering amplitude. Such a method has been used in literature. We suggest a novel, well defined method, to extract the large imaginary part of quasinormal modes via the Coulomb-like phase shift. Furthermore, we compare the numerically evaluated exact scattering amplitude with the Born one to find that the approximation is not very useful for the scattering of massless scalar, electromagnetic as well as gravitational waves from black holes.
CMB-lensing beyond the Born approximation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marozzi, Giovanni; Fanizza, Giuseppe; Durrer, Ruth
2016-09-01
We investigate the weak lensing corrections to the cosmic microwave background temperature anisotropies considering effects beyond the Born approximation. To this aim, we use the small deflection angle approximation, to connect the lensed and unlensed power spectra, via expressions for the deflection angles up to third order in the gravitational potential. While the small deflection angle approximation has the drawback to be reliable only for multipoles ℓ ∼< 2500, it allows us to consistently take into account the non-Gaussian nature of cosmological perturbation theory beyond the linear level. The contribution to the lensed temperature power spectrum coming from the non-Gaussianmore » nature of the deflection angle at higher order is a new effect which has not been taken into account in the literature so far. It turns out to be the leading contribution among the post-Born lensing corrections. On the other hand, the effect is smaller than corrections coming from non-linearities in the matter power spectrum, and its imprint on CMB lensing is too small to be seen in present experiments.« less
Is searching full text more effective than searching abstracts?
Lin, Jimmy
2009-01-01
Background With the growing availability of full-text articles online, scientists and other consumers of the life sciences literature now have the ability to go beyond searching bibliographic records (title, abstract, metadata) to directly access full-text content. Motivated by this emerging trend, I posed the following question: is searching full text more effective than searching abstracts? This question is answered by comparing text retrieval algorithms on MEDLINE® abstracts, full-text articles, and spans (paragraphs) within full-text articles using data from the TREC 2007 genomics track evaluation. Two retrieval models are examined: bm25 and the ranking algorithm implemented in the open-source Lucene search engine. Results Experiments show that treating an entire article as an indexing unit does not consistently yield higher effectiveness compared to abstract-only search. However, retrieval based on spans, or paragraphs-sized segments of full-text articles, consistently outperforms abstract-only search. Results suggest that highest overall effectiveness may be achieved by combining evidence from spans and full articles. Conclusion Users searching full text are more likely to find relevant articles than searching only abstracts. This finding affirms the value of full text collections for text retrieval and provides a starting point for future work in exploring algorithms that take advantage of rapidly-growing digital archives. Experimental results also highlight the need to develop distributed text retrieval algorithms, since full-text articles are significantly longer than abstracts and may require the computational resources of multiple machines in a cluster. The MapReduce programming model provides a convenient framework for organizing such computations. PMID:19192280
Non-perturbative background field calculations
NASA Astrophysics Data System (ADS)
Stephens, C. R.
1988-01-01
New methods are developed for calculating one loop functional determinants in quantum field theory. Instead of relying on a calculation of all the eigenvalues of the small fluctuation equation, these techniques exploit the ability of the proper time formalism to reformulate an infinite dimensional field theoretic problem into a finite dimensional covariant quantum mechanical analog, thereby allowing powerful tools such as the method of Jacobi fields to be used advantageously in a field theory setting. More generally the methods developed herein should be extremely valuable when calculating quantum processes in non-constant background fields, offering a utilitarian alternative to the two standard methods of calculation—perturbation theory in the background field or taking the background field into account exactly. The formalism developed also allows for the approximate calculation of covariances of partial differential equations from a knowledge of the solutions of a homogeneous ordinary differential equation.
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.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-22
... Activities; Proposed Collection; Comment Request; Background Checks for Contractor Employees (Renewal) AGENCY... the electronic docket, go to www.regulations.gov . Title: Background Checks for Contractor Employees... consolidated in 40 CFR part 9. Abstract: The EPA uses contractors to perform services throughout the nation...
Grounding Abstractness: Abstract Concepts and the Activation of the Mouth
Borghi, Anna M.; Zarcone, Edoardo
2016-01-01
One key issue for theories of cognition is how abstract concepts, such as freedom, are represented. According to the WAT (Words As social Tools) proposal, abstract concepts activate both sensorimotor and linguistic/social information, and their acquisition modality involves the linguistic experience more than the acquisition of concrete concepts. We report an experiment in which participants were presented with abstract and concrete definitions followed by concrete and abstract target-words. When the definition and the word matched, participants were required to press a key, either with the hand or with the mouth. Response times and accuracy were recorded. As predicted, we found that abstract definitions and abstract words yielded slower responses and more errors compared to concrete definitions and concrete words. More crucially, there was an interaction between the target-words and the effector used to respond (hand, mouth). While responses with the mouth were overall slower, the advantage of the hand over the mouth responses was more marked with concrete than with abstract concepts. The results are in keeping with grounded and embodied theories of cognition and support the WAT proposal, according to which abstract concepts evoke linguistic-social information, hence activate the mouth. The mechanisms underlying the mouth activation with abstract concepts (re-enactment of acquisition experience, or re-explanation of the word meaning, possibly through inner talk) are discussed. To our knowledge this is the first behavioral study demonstrating with real words that the advantage of the hand over the mouth is more marked with concrete than with abstract concepts, likely because of the activation of linguistic information with abstract concepts. PMID:27777563
Abstract number and arithmetic in preschool children.
Barth, Hilary; La Mont, Kristen; Lipton, Jennifer; Spelke, Elizabeth S
2005-09-27
Educated humans use language to express abstract number, applying the same number words to seven apples, whistles, or sins. Is language or education the source of numerical abstraction? Claims to the contrary must present evidence for numerical knowledge that applies to disparate entities, in people who have received no formal mathematics instruction and cannot express such knowledge in words. Here we show that preschool children can compare and add large sets of elements without counting, both within a single visual-spatial modality (arrays of dots) and across two modalities and formats (dot arrays and tone sequences). In two experiments, children viewed animations and either compared one visible array of dots to a second array or added two successive dot arrays and compared the sum to a third array. In further experiments, a dot array was replaced by a sequence of sounds, so that participants had to integrate quantity information presented aurally and visually. Children performed all tasks successfully, without resorting to guessing strategies or responding to continuous variables. Their accuracy varied with the ratio of the two quantities: a signature of large, approximate number representations in adult humans and animals. Addition was as accurate as comparison, even though children showed no relevant knowledge when presented with symbolic versions of the addition tasks. Abstract knowledge of number and addition therefore precedes, and may guide, language-based instruction in mathematics.
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.…
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.
An approximation theory for the identification of nonlinear distributed parameter systems
NASA Technical Reports Server (NTRS)
Banks, H. T.; Reich, Simeon; Rosen, I. G.
1988-01-01
An abstract approximation framework for the identification of nonlinear distributed parameter systems is developed. Inverse problems for nonlinear systems governed by strongly maximal monotone operators (satisfying a mild continuous dependence condition with respect to the unknown parameters to be identified) are treated. Convergence of Galerkin approximations and the corresponding solutions of finite dimensional approximating identification problems to a solution of the original finite dimensional identification problem is demonstrated using the theory of nonlinear evolution systems and a nonlinear analog of the Trotter-Kato approximation result for semigroups of bounded linear operators. The nonlinear theory developed here is shown to subsume an existing linear theory as a special case. It is also shown to be applicable to a broad class of nonlinear elliptic operators and the corresponding nonlinear parabolic partial differential equations to which they lead. An application of the theory to a quasilinear model for heat conduction or mass transfer is discussed.
Studies of the extreme ultraviolet/soft x-ray background
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stern, R.A.
1978-01-01
The results of an extensive sky survey of the extreme ultraviolet (EUV)/soft x-ray background are reported. The data were obtained with a focusing telescope designed and calibrated at U.C. Berkeley which observed EUV sources and the diffuse background as part of the Apollo-Soyuz mission in July, 1975. With a primary field-of-view of 2.3 + 0.1/sup 0/ FWHM and four EUV bandpass filters (16 to 25, 20 to 73, 80 to 108, and 80 to 250 eV) the EUV telescope obtained background data included in the final observational sample for 21 discrete sky locations and 11 large angular scans, as wellmore » as for a number of shorter observations. Analysis of the data reveals as intense flux above 80 eV energy, with upper limits to the background intensity given for the lower energy filters Ca 2 x 10/sup 4/ and 6 x 10/sup 2/ ph cm/sup -2/ sec/sup -1/ ster/sup -1/ eV/sup -1/ at 21 and 45 eV respectively). The 80 to 108 eV flux agrees within statistical errors with the earlier results of Cash, Malina and Stern (1976): the Apollo-Soyuz average reported intensity is 4.0 +- 1.3 ph cm/sup -2/ sec/sup -1/ ster/sup -1/ eV/sup -1/ at Ca 100 eV, or roughly a factor of ten higher than the corresponding 250 eV intensity. The uniformity of the background flux is uncertain due to limitations in the statistical accuracy of the data; upper limits to the point-to-point standard deviation of the background intensity are (..delta..I/I approximately less than 0.8 +- 0.4 (80 to 108 eV) and approximately less than 0.4 +- 0.2 (80 to 250 eV). No evidence is found for a correlation between the telescope count rate and earth-based parameters (zenith angle, sun angle, etc.) for E approximately greater than 80 eV (the lower energy bandpasses are significantly affected by scattered solar radiation. Unlike some previous claims for the soft x-ray background, no simple dependence upon galactic latitude is seen.« less
Publication Rates of Abstracts Presented at Five National Pharmacy Association Meetings
Prohaska, Emily; Generali, Joyce; Zak, Kevin; Grauer, Dennis
2013-01-01
Background: Abstract presentations at professional meetings provide a medium for disseminating the findings of scholarly activity. Rates of abstract publication from various biomedical disciplines have been evaluated, with pharmacy noted to be lower than other specialties. Previous research on pharmacy abstract publication rates was conducted for a limited number of professional meetings but has not been assessed using Google Scholar. Objective: To determine the full publication rate of abstracts presented at the 2005 American College of Clinical Pharmacy (ACCP) Spring and Annual Meetings, American Pharmacists Association (APhA) Annual Meeting, and American Society of Health-System Pharmacists (ASHP) Summer and Midyear Clinical Meetings. Methods: Publication status was assessed for abstracts presented during the 2005 ACCP Spring and Annual Meetings, APhA Annual Meeting, and ASHP Summer and Midyear Clinical Meetings using PubMed and Google Scholar. Data collected included abstract category, study category, practice site, database(s) in which publication appeared, time in months to publication, publication type, and journal of publication. Results: Evaluation of 2,000 abstracts presented in 2005 revealed an overall full publication rate of 19.8% (n = 384). Nearly all pharmacy abstracts were published as manuscripts (98.4%; n=378) and indexed in PubMed and Google Scholar (91.9%; n = 353), although a significant percentage were indexed in Google Scholar only (7.8%; n = 30). The mean time to full publication was 16.8 months (SD ±11.9 months). Conclusions: Results were consistent with previously reported full publication rates of abstracts from pharmacy association meetings, indicating that abstracts presented at pharmacy meetings continue to have a lower full publication rate than other health disciplines. PMID:24421465
A review on natural background radiation
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
Full-text publication of abstracts presented at European Orthodontic Society congresses.
Livas, Christos; Pandis, Nikolaos; Ren, Yijin
2014-10-01
Empirical evidence has indicated that only a subsample of studies conducted reach full-text publication and this phenomenon has become known as publication bias. A form of publication bias is the selectively delayed full publication of conference abstracts. The objective of this article was to examine the publication status of oral abstracts and poster-presentation abstracts, included in the scientific program of the 82nd and 83rd European Orthodontic Society (EOS) congresses, held in 2006 and 2007, and to identify factors associated with full-length publication. A systematic search of PubMed and Google Scholar databases was performed in April 2013 using author names and keywords from the abstract title to locate abstract and full-article publications. Information regarding mode of presentation, type of affiliation, geographical origin, statistical results, and publication details were collected and analyzed using univariable and multivariable logistic regression. Approximately 51 per cent of the EOS 2006 and 55 per cent of the EOS 2007 abstracts appeared in print more than 5 years post congress. A mean period of 1.32 years elapsed between conference and publication date. Mode of presentation (oral or poster), use of statistical analysis, and research subject area were significant predictors for publication success. Inherent discrepancies of abstract reporting, mainly related to presentation of preliminary results and incomplete description of methods, may be considered in analogous studies. On average 52.2 per cent of the abstracts presented at the two EOS conferences reached full publication. Abstracts presented orally, including statistical analysis, were more likely to get published. © The Author 2013. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Graviton propagator from background-independent quantum gravity.
Rovelli, Carlo
2006-10-13
We study the graviton propagator in Euclidean loop quantum gravity. We use spin foam, boundary-amplitude, and group-field-theory techniques. We compute a component of the propagator to first order, under some approximations, obtaining the correct large-distance behavior. This indicates a way for deriving conventional spacetime quantities from a background-independent theory.
Background-Limited Infrared-Submillimeter Spectroscopy (BLISS)
NASA Technical Reports Server (NTRS)
Bradford, Charles Matt
2004-01-01
The bulk of the cosmic far-infrared background light will soon be resolved into its individual sources with Spitzer, Astro-F, Herschel, and submm/mm ground-based cameras. The sources will be dusty galaxies at z approximately equal to 1-4. Their physical conditions and processes in these galaxies are directly probed with moderate-resolution spectroscopy from 20 micrometers to 1 mm. Currently large cold telescopes are being combined with sensitive direct detectors, offering the potential for mid-far-IR spectroscopy at the background limit (BLISS). The capability will allow routine observations of even modest high-redshift galaxies in a variety of lines. The BLISS instrument's capabilities are described in this presentation.
Nuclear science abstracts (NSA) database 1948--1974 (on the Internet)
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
Nuclear Science Abstracts (NSA) is a comprehensive abstract and index collection of the International Nuclear Science and Technology literature for the period 1948 through 1976. Included are scientific and technical reports of the US Atomic Energy Commission, US Energy Research and Development Administration and its contractors, other agencies, universities, and industrial and research organizations. Coverage of the literature since 1976 is provided by Energy Science and Technology Database. Approximately 25% of the records in the file contain abstracts. These are from the following volumes of the print Nuclear Science Abstracts: Volumes 12--18, Volume 29, and Volume 33. The database containsmore » over 900,000 bibliographic records. All aspects of nuclear science and technology are covered, including: Biomedical Sciences; Metals, Ceramics, and Other Materials; Chemistry; Nuclear Materials and Waste Management; Environmental and Earth Sciences; Particle Accelerators; Engineering; Physics; Fusion Energy; Radiation Effects; Instrumentation; Reactor Technology; Isotope and Radiation Source Technology. The database includes all records contained in Volume 1 (1948) through Volume 33 (1976) of the printed version of Nuclear Science Abstracts (NSA). This worldwide coverage includes books, conference proceedings, papers, patents, dissertations, engineering drawings, and journal literature. This database is now available for searching through the GOV. Research Center (GRC) service. GRC is a single online web-based search service to well known Government databases. Featuring powerful search and retrieval software, GRC is an important research tool. The GRC web site is at http://grc.ntis.gov.« less
PS2-06: Best Practices for Advancing Multi-site Chart Abstraction Research
Blick, Noelle; Cole, Deanna; King, Colleen; Riordan, Rick; Von Worley, Ann; Yarbro, Patty
2012-01-01
Background/Aims Multi-site chart abstraction studies are becoming increasingly common within the HMORN. Differences in systems among HMORN sites can pose significant obstacles to the success of these studies. It is therefore crucial to standardize abstraction activities by following best practices for multi-site chart abstraction, as consistency of processes across sites will increase efficiencies and enhance data quality. Methods Over the past few months the authors have been meeting to identify obstacles to multi-site chart abstraction and to address ways in which multi-site chart abstraction processes can be systemized and standardized. The aim of this workgroup is to create a best practice guide for multi-site chart abstraction studies. Focus areas include: abstractor training, format for chart abstraction (database, paper, etc), data quality, redaction, mechanism for transferring data, site specific access to medical records, IRB/HIPAA concerns, and budgetary issues. Results The results of the workgroup’s efforts (the best practice guide) will be presented by a panel of experts at the 2012 HMORN conference. The presentation format will also focus on discussion among attendees to elicit further input and to identify areas that need to be further addressed. Subsequently, the best practice guide will be posted on the HMORN website. Discussion The best practice guide for multi-site chart abstraction studies will establish sound guidelines and serve as an aid to researchers embarking on multi-site chart abstraction studies. Efficiencies and data quality will be further enhanced with standardized multi-site chart abstraction practices.
Secret loss of unitarity due to the classical background
NASA Astrophysics Data System (ADS)
Yang, I.-Sheng
2017-07-01
We show that a quantum subsystem can become significantly entangled with a classical background through a process with few or no semiclassical backreactions. We study two quantum harmonic oscillators coupled to each other in a time-independent Hamiltonian. We compare it to its semiclassical approximation in which one of the oscillators is treated as the classical background. In this approximation, the remaining quantum oscillator has an effective Hamiltonian which is time-dependent, and its evolution appears to be unitary. However, in the fully quantum model, the two oscillators can entangle each other. Thus, the unitarity of either individual oscillator is never guaranteed. We derive the critical time scale after which the unitarity of either individual oscillator is irrevocably lost. In particular, we give an example that in the adiabatic limit, unitarity is lost before other relevant questions can be addressed.
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…
USSR and Eastern Europe Scientific Abstracts, Engineering and Equipment, Number 38
1977-12-27
THEORY OF STIMULATED EMISSION OF SOUND IN A LIQUID HALF-SPACE WITH UNEVEN BOUNDARY WHEN Q-SWITCHED LASER RADIATION IS ABSORBED Moscow AKUSTICHESKIY...Coherent and Non- linear Optics ["Concerning the Influence of an Uneven Boundary on Optical Stimulation of Sound in a Liquid ," Abstracts of Reports to...switched laser radiation is absorbed in a liquid half-space is considered in the small perturbation approximation. It is assumed that the
NASA Technical Reports Server (NTRS)
Sunyayev, R. A.
1979-01-01
Secondary heating and ionization of the intergalactic gas at redshifts z approximately 10-30 could lead to the large optical depth of the Universe for Thomson scattering and could smooth the primordial fluctuations formed at z approximately 1500. It is shown that the gas motions connected with the large scale density perturbations at z approximately 10-15 must lead to the generation of secondary fluctuations of microwave background. The contribution of the rich clusters of galaxies and young galaxies to the fluctuations of microwave background is also estimated.
2010-01-01
Background Due to language limitations, the abstract of journal article may be the only way for people of non-Chinese speaking countries to know about trials in traditional Chinese medicine (TCM). However, little is known about the reporting quality of these trial abstracts. Our study is to assess the reporting quality of abstracts of randomized controlled trials (RCT) published in four leading Chinese medical journals of TCM, and to identify any differences in reporting between the Chinese and English version of the same abstract publication. Method Two reviewers hand-searched the Chinese Journal of Integrated Traditional and Western Medicine, the Chinese Journal of Integrative Medicine, the China Journal of Chinese Materia Medica and the Chinese Acupuncture & Moxibustion for all abstracts of RCTs published between 2006 and 2007. Two reviewers independently assessed the reporting quality of the Chinese and English version of all eligible abstracts based on a modified version of the CONSORT for reporting randomised trials in journal and conference abstracts (CONSORT for abstracts). Results We identified a total of 345 RCTs of TCM with both a Chinese and English abstract. More than half of Chinese abstracts reported details of the trial participants (68%; 234/345), control group intervention (52%; 179/345), the number of participants randomized (73%; 253/345) and benefits when interpreting the trial results (55%; 190/345). Reporting of methodological quality or key features of trial design and trial results were poor; only 2% (7/345) included details of the trial design, 3% (11/345) defined the primary outcome, 5% (17/345) described the methods of random sequence generation, and only 4% (13/345) reported the number of participants analyzed. No abstracts provided details on allocation concealment and trial registration. The percentage agreement in reporting (between the Chinese and English version of the same abstract) ranged from 84% to 100% across individual
Generalized INF-SUP condition for Chebyshev approximation of the Navier-Stokes equations
NASA Technical Reports Server (NTRS)
Bernardi, Christine; Canuto, Claudio; Maday, Yvon
1986-01-01
An abstract mixed problem and its approximation are studied; both are well-posed if and only if several inf-sup conditions are satisfied. These results are applied to a spectral Galerkin method for the Stokes problem in a square, when it is formulated in Chebyshev weighted Sobolev spaces. Finally, a collocation method for the Navier-Stokes equations at Chebyshev nodes is analyzed.
Normal and compound poisson approximations for pattern occurrences in NGS reads.
Zhai, Zhiyuan; Reinert, Gesine; Song, Kai; Waterman, Michael S; Luan, Yihui; Sun, Fengzhu
2012-06-01
Next generation sequencing (NGS) technologies are now widely used in many biological studies. In NGS, sequence reads are randomly sampled from the genome sequence of interest. Most computational approaches for NGS data first map the reads to the genome and then analyze the data based on the mapped reads. Since many organisms have unknown genome sequences and many reads cannot be uniquely mapped to the genomes even if the genome sequences are known, alternative analytical methods are needed for the study of NGS data. Here we suggest using word patterns to analyze NGS data. Word pattern counting (the study of the probabilistic distribution of the number of occurrences of word patterns in one or multiple long sequences) has played an important role in molecular sequence analysis. However, no studies are available on the distribution of the number of occurrences of word patterns in NGS reads. In this article, we build probabilistic models for the background sequence and the sampling process of the sequence reads from the genome. Based on the models, we provide normal and compound Poisson approximations for the number of occurrences of word patterns from the sequence reads, with bounds on the approximation error. The main challenge is to consider the randomness in generating the long background sequence, as well as in the sampling of the reads using NGS. We show the accuracy of these approximations under a variety of conditions for different patterns with various characteristics. Under realistic assumptions, the compound Poisson approximation seems to outperform the normal approximation in most situations. These approximate distributions can be used to evaluate the statistical significance of the occurrence of patterns from NGS data. The theory and the computational algorithm for calculating the approximate distributions are then used to analyze ChIP-Seq data using transcription factor GABP. Software is available online (www
Equivalent background speed in recovery from motion adaptation.
Simpson, W A; Newman, A; Aasland, W
1997-01-01
We measured, in the same observers, (1) the detectability, d, of a small rotational jump following adaptation to rotational motion and (2) the detectability of the same jump when superimposed on one of several background rotation speeds. Following 90 s of motion adaptation the detectability of the jump was impaired, and sensitivity slowly recovered over the course of 60 s. The detectability of the jump was also impaired by the background speed in a way consistent with a quadratic form of Weber's law. We propose that motion adaptation impairs the detectability of the small jump because it is as if an equivalent background speed has been superimposed on the display. We measured the equivalent background by finding the real background speed that produced the same d' at each instant in the recovery from motion adaptation. The equivalent background started at approximately one to two thirds the speed of the adapting motion, declined rapidly, rose to a small peak at 30 s, then disappeared by 60 s. Since the equivalent background speed corresponds to the speed of the motion aftereffect, we have measured the time course of the motion aftereffect with objective psychophysics.
NASA Technical Reports Server (NTRS)
Gibson, J. S.; Rosen, I. G.
1986-01-01
An abstract approximation framework is developed for the finite and infinite time horizon discrete-time linear-quadratic regulator problem for systems whose state dynamics are described by a linear semigroup of operators on an infinite dimensional Hilbert space. The schemes included the framework yield finite dimensional approximations to the linear state feedback gains which determine the optimal control law. Convergence arguments are given. Examples involving hereditary and parabolic systems and the vibration of a flexible beam are considered. Spline-based finite element schemes for these classes of problems, together with numerical results, are presented and discussed.
Cosmic Infrared Background Fluctuations and Zodiacal Light
NASA Technical Reports Server (NTRS)
Arendt, Richard G.; Kashlinsky, A.; Moseley, S. H.; Mather, J.
2017-01-01
We performed a specific observational test to measure the effect that the zodiacal light can have on measurements of the spatial fluctuations of the near-IR (near-infrared)background. Previous estimates of possible fluctuations caused by zodiacal light have often been extrapolated from observations of the thermal emission at longer wavelengths and low angular resolution or from IRAC (Infrared Array Camera) observations of high-latitude fields where zodiacal light is faint and not strongly varying with time. The new observations analyzed here target the COSMOS (Cosmic Evolution Survey) field at low ecliptic latitude where the zodiacal light intensity varies by factors of approximately 2 over the range of solar elongations at which the field can be observed. We find that the white-noise component of the spatial power spectrum of the background is correlated with the modeled zodiacal light intensity. Roughly half of the measured white noise is correlated with the zodiacal light, but a more detailed interpretation of the white noise is hampered by systematic uncertainties that are evident in the zodiacal light model. At large angular scales (greater than or approximately equal to 100 arcseconds) where excess power above the white noise is observed, we find no correlation of the power with the modeled intensity of the zodiacal light. This test clearly indicates that the large-scale power in the infrared background is not being caused by the zodiacal light.
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.
Bayrakçeken, Fuat
2008-02-01
The reactions of photochemically generated deuterium atoms of selected initial translational energy with ethane have been investigated. At each initial energy the relative probability of the atoms undergoing reaction or energy loss on collision with ethane was investigated, and the phenomenological threshold energy was measured as 30+/-5kJmol(-1) for the abstraction from the secondary C-H bonds. The ratio of relative yields per bond, secondary:primary was approximately 3 at the higher energies studied. The correlation of threshold energies with bond dissociation energies, heats of reaction and activation energies is discussed for abstraction reactions with several hydrocarbons.
New cosmic microwave background constraint to primordial gravitational waves.
Smith, Tristan L; Pierpaoli, Elena; Kamionkowski, Marc
2006-07-14
Primordial gravitational waves (GWs) with frequencies > or approximately equal to 10(-15) Hz contribute to the radiation density of the Universe at the time of decoupling of the cosmic microwave background (CMB). This affects the CMB and matter power spectra in a manner identical to massless neutrinos, unless the initial density perturbation for the GWs is nonadiabatic, as may occur if such GWs are produced during inflation or some post-inflation phase transition. In either case, current observations provide a constraint to the GW amplitude that competes with that from big-bang nucleosynthesis (BBN), although it extends to much lower frequencies (approximately 10(-15) Hz rather than the approximately 10(-10) Hz from BBN): at 95% confidence level, omega(gw)h(2)
Relationship between abstract thinking and eye gaze pattern in patients with schizophrenia
2014-01-01
Background Effective integration of visual information is necessary to utilize abstract thinking, but patients with schizophrenia have slow eye movement and usually explore limited visual information. This study examines the relationship between abstract thinking ability and the pattern of eye gaze in patients with schizophrenia using a novel theme identification task. Methods Twenty patients with schizophrenia and 22 healthy controls completed the theme identification task, in which subjects selected which word, out of a set of provided words, best described the theme of a picture. Eye gaze while performing the task was recorded by the eye tracker. Results Patients exhibited a significantly lower correct rate for theme identification and lesser fixation and saccade counts than controls. The correct rate was significantly correlated with the fixation count in patients, but not in controls. Conclusions Patients with schizophrenia showed impaired abstract thinking and decreased quality of gaze, which were positively associated with each other. Theme identification and eye gaze appear to be useful as tools for the objective measurement of abstract thinking in patients with schizophrenia. PMID:24739356
DOE Office of Scientific and Technical Information (OSTI.GOV)
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.
Approximation methods for inverse problems involving the vibration of beams with tip bodies
NASA Technical Reports Server (NTRS)
Rosen, I. G.
1984-01-01
Two cubic spline based approximation schemes for the estimation of structural parameters associated with the transverse vibration of flexible beams with tip appendages are outlined. The identification problem is formulated as a least squares fit to data subject to the system dynamics which are given by a hybrid system of coupled ordinary and partial differential equations. The first approximation scheme is based upon an abstract semigroup formulation of the state equation while a weak/variational form is the basis for the second. Cubic spline based subspaces together with a Rayleigh-Ritz-Galerkin approach were used to construct sequences of easily solved finite dimensional approximating identification problems. Convergence results are briefly discussed and a numerical example demonstrating the feasibility of the schemes and exhibiting their relative performance for purposes of comparison is provided.
2018 Congress Poster Abstracts
2018-02-21
Each abstract has been indexed according to the first author. Abstracts appear as they were submitted and have not undergone editing or the Oncology Nursing Forum’s review process. Only abstracts that will be presented appear here. Poster numbers are subject to change. For updated poster numbers, visit congress.ons.org or check the Congress guide. Data published in abstracts presented at the ONS 43rd Annual Congress are embargoed until the conclusion of the presentation. Coverage and/or distribution of an abstract, poster, or any of its supplemental material to or by the news media, any commercial entity, or individuals, including the authors of said abstract, is strictly prohibited until the embargo is lifted. Promotion of general topics and speakers is encouraged within these guidelines.
Cosmic background radiation anisotropy in an open inflation, cold dark matter cosmogony
NASA Technical Reports Server (NTRS)
Kamionkowski, Marc; Ratra, Bharat; Spergel, David N.; Sugiyama, Naoshi
1994-01-01
We compute the cosmic background radiation anisotropy, produced by energy-density fluctuations generated during an early epoch of inflation, in an open cosmological model based on the cold dark matter scenario. At Omega(sub 0) is approximately 0.3-0.4, the Cosmic Background Explorer (COBE) normalized open model appears to be consistent with most observations.
Cosmic microwave background bispectrum from recombination.
Huang, Zhiqi; Vernizzi, Filippo
2013-03-08
We compute the cosmic microwave background temperature bispectrum generated by nonlinearities at recombination on all scales. We use CosmoLib2nd, a numerical Boltzmann code at second order to compute cosmic microwave background bispectra on the full sky. We consistently include all effects except gravitational lensing, which can be added to our result using standard methods. The bispectrum is peaked on squeezed triangles and agrees with the analytic approximation in the squeezed limit at the few percent level for all the scales where this is applicable. On smaller scales, we recover previous results on perturbed recombination. For cosmic-variance limited data to l(max)=2000, its signal-to-noise ratio is S/N=0.47, corresponding to f(NL)(eff)=-2.79, and will bias a local signal by f(NL)(loc) ~/= 0.82.
USSR and Eastern Europe Scientific Abstracts, Engineering and Equipment, Number 31
1977-04-18
average coefficient of air absorption is computed by the method of approximate replacement of the real spectrum by the graduated one. The entire range...end of transition area with an accuracy of 15%. Figures 5; References 7. USSR UDC 541.24:532.5 PARAMETRIC METHOD OF CALCULATION OF THERMODYNAMIC...12, 1976 Abstract No 12B723 by V. A. Polyanskiy] GLEBOV, G. A., and KOSHKIN, V. K. [Text] A method is presented for calculation of thermodynamic
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.
NASA Technical Reports Server (NTRS)
Beyer, Andrew D.; Runyan, M. C.; Kenyon, M.; Echternach, P. M .; Chui, T.; Bumble, B.; Bradford, C. M.; Holmes, W. A.; Bock, J. J.
2012-01-01
We report experimental progress toward demonstrating background-limited arrays of membrane-isolated transition-edge sensors (TESs) for the Background Limited Infrared/Sub-mm Spectrograph (BLISS). BLISS is a space-borne instrument with grating spectrometers for wavelengths lambda=35-435 micron and with R=lambda/delta lambda approximately equals 500. The goals for BLISS TESs are: noise equivalent power (NEP) = 5x10 (sup -20) W/Hz(exp 1/2) and response time tau <30ms. We expect background-limited performance from bilayers TESs with T(sub c) = 65mK and G=15fW/K. However, such TESs cannot be operated at 50mK unless stray power on the devices, or dark power P(sub D), is less than 200aW. We describe criteria for measuring P(sub D) that requires accurate knowledge of TC. Ultimately, we fabricated superconducting thermistors from Ir (T(sub c) >= 135mK) and Mo/Cu proximitized bilayers, where T(sub c) is the thermistor transition temperature. We measured the Ir TES arrays in our 50mK adiabatic demagnetization refrigerator test system, which can measure up to eight 1x32 arrays simultaneously using a time-division multiplexer, as well as our single-pixel test system which can measure down to 15mK. In our previous Ir array measurements our best reported performance was NEP=2.5x10(exp -19) W/Hz(sub 1/2) and Tau approximately equals 5ms for straight-beam TESs. In fact, we expected NEP approximately equals 1.5x10(exp -19)?W/Hz(sup 1/2) for meander beam TESs, but did not achieve this previously due to 1/f noise. Here, we detail improvements toward measuring the expected NEP and demonstrate NEP=(1.3+0.2)x10 (sup -19)W/Hz(exp 1/2) in our single-pixel test system and NEP=(1.6+/-0.3)x10(sup -19)W/Hz(sup 1/2) in our array test system.
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.
Large-angle cosmic microwave background anisotropies in an open universe
NASA Technical Reports Server (NTRS)
Kamionkowski, Marc; Spergel, David N.
1994-01-01
If the universe is open, scales larger than the curvature scale may be probed by observation of large-angle fluctuations in the cosmic microwave background (CMB). We consider primordial adiabatic perturbations and discuss power spectra that are power laws in volume, wavelength, and eigenvalue of the Laplace operator. Such spectra may have arisen if, for example, the universe underwent a period of `frustated' inflation. The resulting large-angle anisotropies of the CMB are computed. The amplitude generally increases as Omega is decreased but decreases as h is increased. Interestingly enough, for all three Ansaetze, anisotropies on angular scales larger than the curvature scale are suppressed relative to the anisotropies on scales smaller than the curvature scale, but cosmic variance makes discrimination between various models difficult. Models with 0.2 approximately less than Omega h approximately less than 0.3 appear compatible with CMB fluctuations detected by Cosmic Background Explorer Satellite (COBE) and the Tenerife experiment and with the amplitude and spectrum of fluctuations of galaxy counts in the APM, CfA, and 1.2 Jy IRAS surveys. COBE normalization for these models yields sigma(sub 8) approximately = 0.5 - 0.7. Models with smaller values of Omega h when normalized to COBE require bias factors in excess of 2 to be compatible with the observed galaxy counts on the 8/h Mpc scale. Requiring that the age of the universe exceed 10 Gyr implies that Omega approximately greater than 0.25, while requiring that from the last-scattering term in the Sachs-Wolfe formula, large-angle anisotropies come primarily from the decay of potential fluctuations at z approximately less than 1/Omega. Thus, if the universe is open, COBE has been detecting temperature fluctuations produced at moderate redshift rather than at z approximately 1300.
Abstracting Concepts and Methods.
ERIC Educational Resources Information Center
Borko, Harold; Bernier, Charles L.
This text provides a complete discussion of abstracts--their history, production, organization, publication--and of indexing. Instructions for abstracting are outlined, and standards and criteria for abstracting are stated. Management, automation, and personnel are discussed in terms of possible economies that can be derived from the introduction…
Rational approximations to rational models: alternative algorithms for category learning.
Sanborn, Adam N; Griffiths, Thomas L; Navarro, Daniel J
2010-10-01
Rational models of cognition typically consider the abstract computational problems posed by the environment, assuming that people are capable of optimally solving those problems. This differs from more traditional formal models of cognition, which focus on the psychological processes responsible for behavior. A basic challenge for rational models is thus explaining how optimal solutions can be approximated by psychological processes. We outline a general strategy for answering this question, namely to explore the psychological plausibility of approximation algorithms developed in computer science and statistics. In particular, we argue that Monte Carlo methods provide a source of rational process models that connect optimal solutions to psychological processes. We support this argument through a detailed example, applying this approach to Anderson's (1990, 1991) rational model of categorization (RMC), which involves a particularly challenging computational problem. Drawing on a connection between the RMC and ideas from nonparametric Bayesian statistics, we propose 2 alternative algorithms for approximate inference in this model. The algorithms we consider include Gibbs sampling, a procedure appropriate when all stimuli are presented simultaneously, and particle filters, which sequentially approximate the posterior distribution with a small number of samples that are updated as new data become available. Applying these algorithms to several existing datasets shows that a particle filter with a single particle provides a good description of human inferences.
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.
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.
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.
The Social Background of Students and Their Prospect for Success at School.
ERIC Educational Resources Information Center
Phillipines National Commission for UNESCO.
This document is an English-language abstract (approximately 1,500 words) of a report prepared in answer to an IBE questionnaire. In the Philippines, the main problem is that widespread poverty is responsible for many undernourshed, poorly sheltered and ill clad students whose prospect of success at school is from the start seriously hampered by…
The effect of Limber and flat-sky approximations on galaxy weak lensing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lemos, Pablo; Challinor, Anthony; Efstathiou, George, E-mail: pl411@cam.ac.uk, E-mail: a.d.challinor@ast.cam.ac.uk, E-mail: gpe@ast.cam.ac.uk
We review the effect of the commonly-used Limber and flat-sky approximations on the calculation of shear power spectra and correlation functions for galaxy weak lensing. These approximations are accurate at small scales, but it has been claimed recently that their impact on low multipoles could lead to an increase in the amplitude of the mass fluctuations inferred from surveys such as CFHTLenS, reducing the tension between galaxy weak lensing and the amplitude determined by Planck from observations of the cosmic microwave background. Here, we explore the impact of these approximations on cosmological parameters derived from weak lensing surveys, using themore » CFHTLenS data as a test case. We conclude that the use of small-angle approximations for cosmological parameter estimation is negligible for current data, and does not contribute to the tension between current weak lensing surveys and Planck.« less
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.
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…
A theoretical and shock tube kinetic study on hydrogen abstraction from phenyl formate.
Ning, Hongbo; Liu, Dapeng; Wu, Junjun; Ma, Liuhao; Ren, Wei; Farooq, Aamir
2018-06-12
The hydrogen abstraction reactions of phenyl formate (PF) by different radicals (H/O(3P)/OH/HO2) were theoretically investigated. We calculated the reaction energetics for PF + H/O/OH using the composite method ROCBS-QB3//M06-2X/cc-pVTZ and that for PF + HO2 at the M06-2X/cc-pVTZ level of theory. The high-pressure limit rate constants were calculated using the transition state theory in conjunction with the 1-D hindered rotor approximation and tunneling correction. Three-parameter Arrhenius expressions of rate constants were provided over the temperature range of 500-2000 K. To validate the theoretical calculations, the overall rate constants of PF + OH → Products were measured in shock tube experiments at 968-1128 K and 1.16-1.25 atm using OH laser absorption. The predicted overall rate constants agree well with the shock tube data (within 15%) over the entire experimental conditions. Rate constant analysis indicates that the H-abstraction at the formic acid site dominates the PF consumption, whereas the contribution of H-abstractions at the aromatic ring increases with temperature. Additionally, comparisons of site-specific H-abstractions from PF with methyl formate, ethyl formate, benzene, and toluene were performed to understand the effects of the aromatic ring and side-chain substituent on H-abstraction rate constants.
Katsikadakos, D; Hardalupas, Y; Taylor, A M K P; Hunt, P A
2012-07-21
Hydrogen abstraction reactions by the methyl radical from n-butanol have been investigated at the ROCBS-QB3 level of theory. Reaction energies and product geometries for the most stable conformer of n-butanol (ROH) have been computed, the reaction energies order α < γ < β < δ < OH. The preference for n-butane to favour H-abstraction at C(β) and C(γ) while, in contrast, n-butanol favours radical reactions at the C(α) carbon is rationalised. Transition state (TS) barriers and geometries for the most stable conformer of n-butanol are presented, and discussed with respect to the Hammond postulate. The reaction barriers order as α < OH < γ < β < δ. This relative ordering is not consistent with product radical stability, C-H bond dissociation energies or previous studies using O[combining dot above]H and HO[combining dot above](2) radicals. We provide a molecular orbital based rationalisation for this ordering and answer two related questions: Why is the γ-channel more stable than the β-channel? Why do the two C(γ)-H H-abstraction TS differ in energy? The method and basis set dependence of the TS barriers is investigated. The Boltzmann probability distribution for the n-butanol conformers suggests that low energy conformers are present in approximately equal proportions to the most stable conformer at combustion temperatures where ĊH(3) radicals are present. Thus, the relative significance of the various H-abstraction channels has been assessed for a selection of higher energy conformers (ROH'). Key results include finding that higher energy n-butanol conformers (E(ROH') > E(ROH)) can generate lower energy product radicals, E(ROH') < E(ROH). Moreover, higher energy conformers can also have a globally competitive TS energy for H-abstraction.
The Social Background of Students and Their Prospect of Success at School.
ERIC Educational Resources Information Center
Kaniel, Soshana
This document is an English-language abstract (approximately 1,500 words) of a report prepared by a research worker in reply to an IBE questionnaire on the subject. The goal of Israeli education policy has been to raise the educational level of the more backward immigrants to Israel who form a large culturally deprived group, while maintaining an…
ASTRONAUTICS INFORMATION. Abstracts Vol. III, No. 1. Abstracts 3,082- 3,184
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1961-01-01
Abstracts are presented on astronautics. The abstracts are generally restricted to spaceflight and to applicable techniques and data. The publication covers the period of January 1961. 102 references. (J.R.D.)
ASTRONAUTICS INFORMATION. ABSTRACTS, VOL. V, NO. 3. Abstracts 5,201- 5,330
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hardgrove, B.J.; Warren, F.L. comps.
1962-03-01
Abstracts of astronautics information covering the period March 1962 are presented. The 129 abstracts cover the subject of spaceflight and applicable data and techniques. Author, subject, and source indexes are included. (M.C.G.)
Approximate Dynamic Programming: Combining Regional and Local State Following Approximations.
Deptula, Patryk; Rosenfeld, Joel A; Kamalapurkar, Rushikesh; Dixon, Warren E
2018-06-01
An infinite-horizon optimal regulation problem for a control-affine deterministic system is solved online using a local state following (StaF) kernel and a regional model-based reinforcement learning (R-MBRL) method to approximate the value function. Unlike traditional methods such as R-MBRL that aim to approximate the value function over a large compact set, the StaF kernel approach aims to approximate the value function in a local neighborhood of the state that travels within a compact set. In this paper, the value function is approximated using a state-dependent convex combination of the StaF-based and the R-MBRL-based approximations. As the state enters a neighborhood containing the origin, the value function transitions from being approximated by the StaF approach to the R-MBRL approach. Semiglobal uniformly ultimately bounded (SGUUB) convergence of the system states to the origin is established using a Lyapunov-based analysis. Simulation results are provided for two, three, six, and ten-state dynamical systems to demonstrate the scalability and performance of the developed method.
Alter, David; Grenache, David G; Bosler, David S; Karcher, Raymond E; Nichols, James; Rajadhyaksha, Aparna; Camelo-Piragua, Sandra; Rauch, Carol; Huddleston, Brent J; Frank, Elizabeth L; Sluss, Patrick M; Lewandrowski, Kent; Eichhorn, John H; Hall, Janet E; Rahman, Saud S; McPherson, Richard A; Kiechle, Frederick L; Hammett-Stabler, Catherine; Pierce, Kristin A; Kloehn, Erica A; Thomas, Patricia A; Walts, Ann E; Madan, Rashna; Schlesinger, Kathie; Nawgiri, Ranjana; Bhutani, Manoop; Kanber, Yonca; Abati, Andrea; Atkins, Kristen A; Farrar, Robert; Gopez, Evelyn Valencerina; Jhala, Darshana; Griffin, Sonya; Jhala, Khushboo; Jhala, Nirag; Bentz, Joel S; Emerson, Lyska; Chadwick, Barbara E; Barroeta, Julieta E; Baloch, Zubair W; Collins, Brian T; Middleton, Owen L; Davis, Gregory G; Haden-Pinneri, Kathryn; Chu, Albert Y; Keylock, Joren B; Ramoso, Robert; Thoene, Cynthia A; Stewart, Donna; Pierce, Arand; Barry, Michelle; Aljinovic, Nika; Gardner, David L; Barry, Michelle; Shields, Lisa B E; Arnold, Jack; Stewart, Donna; Martin, Erica L; Rakow, Rex J; Paddock, Christopher; Zaki, Sherif R; Prahlow, Joseph A; Stewart, Donna; Shields, Lisa B E; Rolf, Cristin M; Falzon, Andrew L; Hudacki, Rachel; Mazzella, Fermina M; Bethel, Melissa; Zarrin-Khameh, Neda; Gresik, M Vicky; Gill, Ryan; Karlon, William; Etzell, Joan; Deftos, Michael; Karlon, William J; Etzell, Joan E; Wang, Endi; Lu, Chuanyi M; Manion, Elizabeth; Rosenthal, Nancy; Wang, Endi; Lu, Chuanyi M; Tang, Patrick; Petric, Martin; Schade, Andrew E; Hall, Geraldine S; Oethinger, Margret; Hall, Geraldine; Picton, Avis R; Hoang, Linda; Imperial, Miguel Ranoa; Kibsey, Pamela; Waites, Ken; Duffy, Lynn; Hall, Geraldine S; Salangsang, Jo-Anne M; Bravo, Lulette Tricia C; Oethinger, Margaret D; Veras, Emanuela; Silva, Elvia; Vicens, Jimena; Silva, Elvio; Keylock, Joren; Hempel, James; Rushing, Elizabeth; Posligua, Lorena E; Deavers, Michael T; Nash, Jason W; Basturk, Olca; Perle, Mary Ann; Greco, Alba; Lee, Peng; Maru, Dipen; Weydert, Jamie Allen; Stevens, Todd M; Brownlee, Noel A; Kemper, April E; Williams, H James; Oliverio, Brock J; Al-Agha, Osama M; Eskue, Kyle L; Newlands, Shawn D; Eltorky, Mahmoud A; Puri, Puja K; Royer, Michael C; Rush, Walter L; Tavora, Fabio; Galvin, Jeffrey R; Franks, Teri J; Carter, James Elliot; Kahn, Andrea Graciela; Lozada Muñoz, Luis R; Houghton, Dan; Land, Kevin J; Nester, Theresa; Gildea, Jacob; Lefkowitz, Jerry; Lacount, Rachel A; Thompson, Hannis W; Refaai, Majed A; Quillen, Karen; Lopez, Ana Ortega; Goldfinger, Dennis; Muram, Talia; Thompson, Hannis
2009-02-01
The following abstracts are compiled from Check Sample exercises published in 2008. These peer-reviewed case studies assist laboratory professionals with continuing medical education and are developed in the areas of clinical chemistry, cytopathology, forensic pathology, hematology, microbiology, surgical pathology, and transfusion medicine. Abstracts for all exercises published in the program will appear annually in AJCP.
Students' Moral Reasoning as Related to Cultural Background and Educational Experience.
ERIC Educational Resources Information Center
Bar-Yam, Miriam; And Others
The relationship between moral development and cultural and educational background is examined. Approximately 120 Israeli youth representing different social classes, sex, religious affiliation, and educational experience were interviewed. The youth interviewed included urban middle and lower class students, Kibbutz-born, Youth Aliyah…
1989-06-15
Andes near Santiago de Chile extinction coefficients have been determined at elevations above 3000 meters. Values betwee 0.018 km and 0.15 km have been...McGovern 1515 North Atlantic Aerosol Background concentrations measured at a Hebridean coastal site N.H. Smith, P.M. Park and I.E. Consterdine 1530...ocean V. Dreiling, R. Maser and L. Schutz 1615 Measurements of aerosol concentration and distribution at Helgoland Island P. Brand, J. Gebhart, M. Below
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.
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
Countably QC-Approximating Posets
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 σ c(L)op of all σ-Scott-closed subsets of L is weakly generalized countably approximating. PMID:25165730
Relativistic electron plasma oscillations in an inhomogeneous ion background
NASA Astrophysics Data System (ADS)
Karmakar, Mithun; Maity, Chandan; Chakrabarti, Nikhil
2018-06-01
The combined effect of relativistic electron mass variation and background ion inhomogeneity on the phase mixing process of large amplitude electron oscillations in cold plasmas have been analyzed by using Lagrangian coordinates. An inhomogeneity in the ion density is assumed to be time-independent but spatially periodic, and a periodic perturbation in the electron density is considered as well. An approximate space-time dependent solution is obtained in the weakly-relativistic limit by employing the Bogolyubov and Krylov method of averaging. It is shown that the phase mixing process of relativistically corrected electron oscillations is strongly influenced by the presence of a pre-existing ion density ripple in the plasma background.
Polnaszek, Brock; Gilmore-Bykovskyi, Andrea; Hovanes, Melissa; Roiland, Rachel; Ferguson, Patrick; Brown, Roger; Kind, Amy JH
2014-01-01
Background Unstructured data encountered during retrospective electronic medical record (EMR) abstraction has routinely been identified as challenging to reliably abstract, as this data is often recorded as free text, without limitations to format or structure. There is increased interest in reliably abstracting this type of data given its prominent role in care coordination and communication, yet limited methodological guidance exists. Objective As standard abstraction approaches resulted in sub-standard data reliability for unstructured data elements collected as part of a multi-site, retrospective EMR study of hospital discharge communication quality, our goal was to develop, apply and examine the utility of a phase-based approach to reliably abstract unstructured data. This approach is examined using the specific example of discharge communication for warfarin management. Research Design We adopted a “fit-for-use” framework to guide the development and evaluation of abstraction methods using a four step, phase-based approach including (1) team building, (2) identification of challenges, (3) adaptation of abstraction methods, and (4) systematic data quality monitoring. Measures Unstructured data elements were the focus of this study, including elements communicating steps in warfarin management (e.g., warfarin initiation) and medical follow-up (e.g., timeframe for follow-up). Results After implementation of the phase-based approach, inter-rater reliability for all unstructured data elements demonstrated kappas of ≥ 0.89 -- an average increase of + 0.25 for each unstructured data element. Conclusions As compared to standard abstraction methodologies, this phase-based approach was more time intensive, but did markedly increase abstraction reliability for unstructured data elements within multi-site EMR documentation. PMID:27624585
Quantum gravitational contributions to the cosmic microwave background anisotropy spectrum.
Kiefer, Claus; Krämer, Manuel
2012-01-13
We derive the primordial power spectrum of density fluctuations in the framework of quantum cosmology. For this purpose we perform a Born-Oppenheimer approximation to the Wheeler-DeWitt equation for an inflationary universe with a scalar field. In this way, we first recover the scale-invariant power spectrum that is found as an approximation in the simplest inflationary models. We then obtain quantum gravitational corrections to this spectrum and discuss whether they lead to measurable signatures in the cosmic microwave background anisotropy spectrum. The nonobservation so far of such corrections translates into an upper bound on the energy scale of inflation.
ERIC Educational Resources Information Center
American Biology Teacher, 1976
1976-01-01
Presents abstracts of 63 papers to be presented at the 1976 Convention of the National Association of Biology Teachers, October 14-17, 1976, Denver, Colorado. Papers cover a wide range of biology and science education topics with the majority concentrating upon the convention's main program, "Ecosystems: 1776-1976-?". (SL)
1982-12-01
Third Molars in Naval Personnel,- (Abstract #1430) 7. A. SEROWSKI* and F. AKER --"The Effect of Marine and Fresh-Water Atmospheric Environments on...Packaged Dental Instrument4’, (Abstract #1133) 8. I. L. SHKLAIR*, R. W. GAUGLER, R. G. WALTER -.The Effect of Three Surfactants on Controlling Caries...Insoluble Streptococcal Glucan"’. e (Abstract #102) - _/_ / 10. R. G. WALTER* and I. L. SHKLAIR - The Effect of T-10 Dextran on Caries and Plaque in
Approximate Dispersion Relations for Waves on Arbitrary Shear Flows
NASA Astrophysics Data System (ADS)
Ellingsen, S. À.; Li, Y.
2017-12-01
An approximate dispersion relation is derived and presented for linear surface waves atop a shear current whose magnitude and direction can vary arbitrarily with depth. The approximation, derived to first order of deviation from potential flow, is shown to produce good approximations at all wavelengths for a wide range of naturally occuring shear flows as well as widely used model flows. The relation reduces in many cases to a 3-D generalization of the much used approximation by Skop (1987), developed further by Kirby and Chen (1989), but is shown to be more robust, succeeding in situations where the Kirby and Chen model fails. The two approximations incur the same numerical cost and difficulty. While the Kirby and Chen approximation is excellent for a wide range of currents, the exact criteria for its applicability have not been known. We explain the apparently serendipitous success of the latter and derive proper conditions of applicability for both approximate dispersion relations. Our new model has a greater range of applicability. A second order approximation is also derived. It greatly improves accuracy, which is shown to be important in difficult cases. It has an advantage over the corresponding second-order expression proposed by Kirby and Chen that its criterion of accuracy is explicitly known, which is not currently the case for the latter to our knowledge. Our second-order term is also arguably significantly simpler to implement, and more physically transparent, than its sibling due to Kirby and Chen.<abstract type="synopsis">
Thermal effects and sudden decay approximation in the curvaton scenario
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kitajima, Naoya; Takesako, Tomohiro; Yokoyama, Shuichiro
2014-10-01
We study the impact of a temperature-dependent curvaton decay rate on the primordial curvature perturbation generated in the curvaton scenario. Using the familiar sudden decay approximation, we obtain an analytical expression for the curvature perturbation after the decay of the curvaton. We then investigate numerically the evolution of the background and of the perturbations during the decay. We first show that the instantaneous transfer coefficient, related to the curvaton energy fraction at the decay, can be extended into a more general parameter, which depends on the net transfer of the curvaton energy into radiation energy or, equivalently, on the totalmore » entropy ratio after the complete curvaton decay. We then compute the curvature perturbation and compare this result with the sudden decay approximation prediction.« less
NASA Astrophysics Data System (ADS)
Sharpanskykh, Alexei; Treur, Jan
Employing rich internal agent models of actors in large-scale socio-technical systems often results in scalability issues. The problem addressed in this paper is how to improve computational properties of a complex internal agent model, while preserving its behavioral properties. The problem is addressed for the case of an existing affective-cognitive decision making model instantiated for an emergency scenario. For this internal decision model an abstracted behavioral agent model is obtained, which ensures a substantial increase of the computational efficiency at the cost of approximately 1% behavioural error. The abstraction technique used can be applied to a wide range of internal agent models with loops, for example, involving mutual affective-cognitive interactions.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Gortais, Bernard
2003-07-29
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.
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…
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.
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.
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.
A method to characterise site, urban and regional ambient background radiation.
Passmore, C; Kirr, M
2011-03-01
Control dosemeters are routinely provided to customers to monitor the background radiation so that it can be subtracted from the gross response of the dosemeter to arrive at the occupational dose. Landauer, the largest dosimetry processor in the world with subsidiaries in Australia, Brazil, China, France, Japan, Mexico and the UK, has clients in approximately 130 countries. The Glenwood facility processes over 1.1 million controls per year. This network of clients around the world provides a unique ability to monitor the world's ambient background radiation. Control data can be mined to provide useful historical information regarding ambient background rates and provide a historical baseline for geographical areas. Historical baseline can be used to provide site or region-specific background subtraction values, document the variation in ambient background radiation around a client's site or provide a baseline for measuring the efficiency of clean-up efforts in urban areas after a dirty bomb detonation.
Abstraction and reformulation in artificial intelligence.
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
Abstraction and reformulation in artificial intelligence.
Holte, Robert C; Choueiry, Berthe Y
2003-07-29
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.
Approximate symmetries of Hamiltonians
NASA Astrophysics Data System (ADS)
Chubb, Christopher T.; Flammia, Steven T.
2017-08-01
We explore the relationship between approximate symmetries of a gapped Hamiltonian and the structure of its ground space. We start by considering approximate symmetry operators, defined as unitary operators whose commutators with the Hamiltonian have norms that are sufficiently small. We show that when approximate symmetry operators can be restricted to the ground space while approximately preserving certain mutual commutation relations. We generalize the Stone-von Neumann theorem to matrices that approximately satisfy the canonical (Heisenberg-Weyl-type) commutation relations and use this to show that approximate symmetry operators can certify the degeneracy of the ground space even though they only approximately form a group. Importantly, the notions of "approximate" and "small" are all independent of the dimension of the ambient Hilbert space and depend only on the degeneracy in the ground space. Our analysis additionally holds for any gapped band of sufficiently small width in the excited spectrum of the Hamiltonian, and we discuss applications of these ideas to topological quantum phases of matter and topological quantum error correcting codes. Finally, in our analysis, we also provide an exponential improvement upon bounds concerning the existence of shared approximate eigenvectors of approximately commuting operators under an added normality constraint, which may be of independent interest.
NASA Astrophysics Data System (ADS)
Wüst, Sabine; Wendt, Verena; Linz, Ricarda; Bittner, Michael
2017-09-01
Cubic splines with equidistant spline sampling points are a common method in atmospheric science, used for the approximation of background conditions by means of filtering superimposed fluctuations from a data series. What is defined as background or superimposed fluctuation depends on the specific research question. The latter also determines whether the spline or the residuals - the subtraction of the spline from the original time series - are further analysed.Based on test data sets, we show that the quality of approximation of the background state does not increase continuously with an increasing number of spline sampling points and/or decreasing distance between two spline sampling points. Splines can generate considerable artificial oscillations in the background and the residuals.We introduce a repeating spline approach which is able to significantly reduce this phenomenon. We apply it not only to the test data but also to TIMED-SABER temperature data and choose the distance between two spline sampling points in a way that is sensitive for a large spectrum of gravity waves.
Massanari, R M; Wilkerson, K; Streed, S A; Hierholzer, W J
1987-01-01
Proper reporting of discharge diagnoses, including complications of medical care, is essential for maximum recovery of revenues under the prospective reimbursement system. To evaluate the effectiveness of abstracting techniques in identifying nosocomial infections at discharge, discharge abstracts of patients with nosocomial infections were reviewed during September through November of 1984. Patients with nosocomial infections were identified using modified Centers for Disease Control (CDC) definitions and trained surveillance technicians. Records which did not include the diagnosis of nosocomial infections in the discharge abstract were identified, and potential lost revenues were estimated. We identified 631 infections in 498 patients. On average, only 57 per cent of the infections were properly recorded and coded in the discharge abstract. Of the additional monies which might be anticipated by the health care institution to assist in the cost of care of adverse events, approximately one-third would have been lost due to errors in coding in the discharge abstract. Although these lost revenues are substantial, they constitute but a small proportion of the potential costs to the institution when patients acquire nosocomial infections. PMID:3105338
Approximate Synchrony: An Abstraction for Distributed Almost Synchronous Systems
2015-05-29
finding bugs. Verification of the TSCH Protocol. Time Synchronized Channel Hopping (TSCH) is a Medium Access Control scheme that enables low power...allotted by the schedule and remain in sleep mode otherwise. In the ab- sence of precise time-synchronization, the time-slots across nodes would not be
Kazerani, Maryam; Davoudian, Atefeh; Zayeri, Farid; Soori, Hamid
2017-01-01
Background: Systematic reviews and meta-analysis have significant advantages over conventional reviews in that all available data should be presented. This study aimed to evaluate Iranian systematic reviews and meta-analysis abstracts indexed in WOS and Scopus during 2003-2012 based on PRISMA checklist. Methods: This is an analytical study. We evaluated 46 article abstracts indexed in WOS, 89 article abstracts indexed in Scopus and 158 article abstracts indexed in WOS and Scopus both (overlapped group). The quality of the abstracts was evaluated according to the PRISMA checklist for abstracts. Some indicators including distribution per year, total citation, average citations per year, average citations per documents and average citations per year in each article were determined through searching the WOS and Scopus Databases' analytical section. Then, the correlations between the abstract's PRISMA scores, average citations per year, and publication year were calculated. Results: The abstract's quality is not desirable as far as the PRISMA criteria are concerned. In other words, none of the articles' abstracts is in line with the PRISMA items. The average of scores of the current study was 5.9 while the maximum score was 12. The PRISMA criteria showed the highest compliance with "Objectives" (98.6%), the second highest with "Synthesis of result" (85%) and "Title" (80.2%) and the lowest compliance with "Registration" (2%). There was a positive correlation between the compliance of PRISMA score and the average citations per year while there was a negative correlation between PRISMA score and the publication year. Conclusion: It seems that the suggested criteria for reporting Iranian systematic reviews and meta-analysis are not considered adequately by the writers and even scientific journal editors.
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
Metacognition and abstract reasoning.
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.
Gürses, İlke Ali; Gayretli, Özcan; Gürtekin, Başak; Öztürk, Adnan
2017-01-01
Background: Despite significant efforts made for, most abstracts presented during a meeting do not proceed and publish as a manuscript in scientific journals. Aims: To investigate publication rates of national anatomy congresses. Study Design: Descriptive study. Methods: All abstracts presented at two annual meetings in 2007 and 2008 were extracted. PubMed and Google Scholar database search used for publication history. Presentation and study types, publication rates and mean publishing times were evaluated. Inconsistency rates between meeting abstract and final published article were also considered. Results: Among 342 abstracts, 195 (57%) were followed by a full-text article. Publication rates for oral and poster presentations were 75% and 52.2%, respectively. The mean publication time was 23.7±23 months. Overall, 89.2% of the articles were published within 5 years. There were no inconsistencies in 50 (25.6%) articles, while 145 (74.4%) had inconsistencies compared to the abstracts presented at the congress. Getting adequate information for 45 (23.1%) articles was not possible. There was no standard reporting format for the abstracts. Conclusion: Our study shows that, overall publication rates for abstracts presented at national anatomy meetings were higher than those presented at national meetings for clinical specialties. PMID:28251026
Concept Formation and Abstraction.
ERIC Educational Resources Information Center
Lunzer, Eric A.
1979-01-01
This paper examines the nature of concepts and conceptual processes and the manner of their formation. It argues that a process of successive abstraction and systematization is central to the evolution of conceptual structures. Classificatory processes are discussed and three levels of abstraction outlined. (Author/SJL)
Abstraction Techniques for Parameterized Verification
2006-11-01
approach for applying model checking to unbounded systems is to extract finite state models from them using conservative abstraction techniques. Prop...36 2.5.1 Multiple Reference Processes . . . . . . . . . . . . . . . . . . . 36 2.5.2 Adding Monitor Processes...model checking to complex pieces of code like device drivers depends on the use of abstraction methods. An abstraction method extracts a small finite
The abstract is only allowed to be 500 words maximum and is supposed to represent the theme of the conference so I am focusing my information more on the background of why phosphorus is important to recovery then giving a little less detail on the material I've made for this purp...
Geophysical abstracts 167, October-December 1956
Rabbitt, Mary C.; Vitaliano, Dorothy B.; Vesselowsky, S.T.; ,
1956-01-01
Geophysical Abstracts includes abstracts of technical papers and books on the physics of the solid earth, the application of physical methods and techniques to geologic problems, and geophysical exploration. The table of contents, which is alphabetically arranged, shows the material covered.Abstracts are prepared only of material that is believed to be generally available. Ordinarily abstracts are not published of material with limited circulation (such as dissertations, open-file reports, or memoranda) or of other papers presented orally at meetings unless summaries of substantial length are published. Abstracts of papers in Japanese and Chinese are based on abstracts or summaries in a western language accompanying the paper.
Geophysical abstracts 164, January-March 1956
Rabbitt, Mary C.; Vitaliano, Dorothy B.; Vesselowsky, S.T.; ,
1956-01-01
Geophysical Abstracts includes abstracts of technical papers and books on the physics of the solid earth, the application of physical methods and techniques to geologic problems, and geophysical exploration. A new table of contents, alphabetically arranged, has been adapted to show more clearly the material covered.Abstracts are prepared only of material that is believed to be generally available. Ordinarily abstracts are not published of material with limited circulation (such as dissertations, open-file reports, or memoranda) or of papers presented orally at meetings unless summaries of substantial length are published. Abstracts of papers in Japanese and Chinese are based on abstracts or summaries in a western language accompanying the paper.
Geophysical abstracts 166, July-September 1956
Rabbitt, Mary C.; Vitaliano, Dorothy B.; Vesselowsky, S.T.; ,
1956-01-01
Geophysical Abstracts includes abstracts of technical papers and books on the physics of the solid earth, the application of physical methods and techniques to geologic problems, and geophysical exploration. The table of contents, which is alphabetically arranged, shows the material covered.Abstracts are prepared only of material that is believed to be generally available. Ordinarily abstracts are not published of material with limited circulation (such as dissertations, open-file reports, or memoranda) or of other papers presented orally at meetings unless summaries of substantial length are published. Abstracts of papers in Japanese and Chinese are based on abstracts or summaries in a western language accompanying the paper.
Geophysical abstracts 165, April-June 1956
Rabbitt, Mary C.; Vitaliano, Dorothy B.; Vesselowsky, S.T.; ,
1956-01-01
Geophysical Abstracts includes abstracts of technical papers and books on the physics of the solid earth, the application of physical methods and techniques to geologic problems, and geophysical exploration. The table of contents, which is alphabetically arranged, shows the material covered.Abstracts are prepared only of material that is believed to be generally available. Ordinarily abstracts are not published of material with limited circulation (such as dissertations, open-file reports, or memoranda) or of other papers presented orally at meetings unless summaries of substantial length are published. Abstracts of papers in Japanese and Chinese are based on abstracts or summaries in a western language accompanying the paper.
Neural network submodel as an abstraction tool: relating network performance to combat outcome
NASA Astrophysics Data System (ADS)
Jablunovsky, Greg; Dorman, Clark; Yaworsky, Paul S.
2000-06-01
Simulation of Command and Control (C2) networks has historically emphasized individual system performance with little architectural context or credible linkage to `bottom- line' measures of combat outcomes. Renewed interest in modeling C2 effects and relationships stems from emerging network intensive operational concepts. This demands improved methods to span the analytical hierarchy between C2 system performance models and theater-level models. Neural network technology offers a modeling approach that can abstract the essential behavior of higher resolution C2 models within a campaign simulation. The proposed methodology uses off-line learning of the relationships between network state and campaign-impacting performance of a complex C2 architecture and then approximation of that performance as a time-varying parameter in an aggregated simulation. Ultimately, this abstraction tool offers an increased fidelity of C2 system simulation that captures dynamic network dependencies within a campaign context.
Energy Research Abstracts. [DOE abstract journal
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-01-01
Energy Research Abstracts (ERA) provides abstracting and indexing coverage of all scientific and technical reports, journal articles, conference papers and proceedings, books, patents, theses, and monographs originated by the US Department of Energy, its laboratories, energy centers, and contractors. ERA also covers other energy information prepared in report form by federal and state government organizations, foreign governments, and domestic and foreign universities and research organizations. ERA coverage of non-report literature is limited to that generated by Department of Energy activity. ERA is comprehensive in its subject scope, encompassing the DOE's research, development, demonstration, and technological programs resulting from its broadmore » charter for energy sources, conservation, safety, environmental impacts, and regulation. Corporate, author, subject, report number, and contract number indexes are included. ERA is available on an exchange basis to universities, research intitutions, industrial firms, and publishers of scientific information. Federal, state, and municipal agencies concerned with energy development, conservation, and usage may obtain ERA free of charge. Inquiries should be directed to the Technical Information Center, P.O. Box 62, Oak Ridge, Tennessee 37830. ERA is available to the public on a subscription basis for 24 semimonthly issues including a semiannual index and an annual index. All citations announced in ERA exist as separate records in the DOE Energy Data Base.« less
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.
Padé Approximant and Minimax Rational Approximation in Standard Cosmology
NASA Astrophysics Data System (ADS)
Zaninetti, Lorenzo
2016-02-01
The luminosity distance in the standard cosmology as given by $\\Lambda$CDM and consequently the distance modulus for supernovae can be defined by the Pad\\'e approximant. A comparison with a known analytical solution shows that the Pad\\'e approximant for the luminosity distance has an error of $4\\%$ at redshift $= 10$. A similar procedure for the Taylor expansion of the luminosity distance gives an error of $4\\%$ at redshift $=0.7 $; this means that for the luminosity distance, the Pad\\'e approximation is superior to the Taylor series. The availability of an analytical expression for the distance modulus allows applying the Levenberg--Marquardt method to derive the fundamental parameters from the available compilations for supernovae. A new luminosity function for galaxies derived from the truncated gamma probability density function models the observed luminosity function for galaxies when the observed range in absolute magnitude is modeled by the Pad\\'e approximant. A comparison of $\\Lambda$CDM with other cosmologies is done adopting a statistical point of view.
Measurement of the cosmic microwave background spectrum by the COBE FIRAS instrument
NASA Technical Reports Server (NTRS)
Mather, J. C.; Cheng, E. S.; Cottingham, D. A.; Eplee, R. E., Jr.; Fixsen, D. J.; Hewagama, T.; Isaacman, R. B.; Jensen, K. A.; Meyer, S. S.; Noerdlinger, P. D.
1994-01-01
The cosmic microwave background radiation (CMBR) has a blackbody spectrum within 3.4 x 10(exp -8) ergs/sq cm/s/sr cm over the frequency range from 2 to 20/cm (5-0.5 mm). These measurements, derived from the Far-Infrared Absolute Spectrophotomer (FIRAS) instrument on the Cosmic Background Explorer (COBE) satellite, imply stringent limits on energy release in the early universe after t approximately 1 year and redshift z approximately 3 x 10(exp 6). The deviations are less than 0.30% of the peak brightness, with an rms value of 0.01%, and the dimensionless cosmological distortion parameters are limited to the absolute value of y is less than 2.5 x 10(exp -5) and the absolute value of mu is less than 3.3 x 10(exp -4) (95% confidence level). The temperature of the CMBR is 2.726 +/- 0.010 K (95% confidence level systematic).
Kazerani, Maryam; Davoudian, Atefeh; Zayeri, Farid; Soori, Hamid
2017-01-01
Background: Systematic reviews and meta-analysis have significant advantages over conventional reviews in that all available data should be presented. This study aimed to evaluate Iranian systematic reviews and meta-analysis abstracts indexed in WOS and Scopus during 2003-2012 based on PRISMA checklist. Methods: This is an analytical study. We evaluated 46 article abstracts indexed in WOS, 89 article abstracts indexed in Scopus and 158 article abstracts indexed in WOS and Scopus both (overlapped group). The quality of the abstracts was evaluated according to the PRISMA checklist for abstracts. Some indicators including distribution per year, total citation, average citations per year, average citations per documents and average citations per year in each article were determined through searching the WOS and Scopus Databases’ analytical section. Then, the correlations between the abstract's PRISMA scores, average citations per year, and publication year were calculated. Results: The abstract’s quality is not desirable as far as the PRISMA criteria are concerned. In other words, none of the articles’ abstracts is in line with the PRISMA items. The average of scores of the current study was 5.9 while the maximum score was 12. The PRISMA criteria showed the highest compliance with "Objectives" (98.6%), the second highest with "Synthesis of result" (85%) and "Title" (80.2%) and the lowest compliance with "Registration" (2%). There was a positive correlation between the compliance of PRISMA score and the average citations per year while there was a negative correlation between PRISMA score and the publication year. Conclusion: It seems that the suggested criteria for reporting Iranian systematic reviews and meta-analysis are not considered adequately by the writers and even scientific journal editors. PMID:28955668
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…
Scientific meeting abstracts: significance, access, and trends.
Kelly, J A
1998-01-01
Abstracts of scientific papers and posters that are presented at annual scientific meetings of professional societies are part of the broader category of conference literature. They are an important avenue for the dissemination of current data. While timely and succinct, these abstracts present problems such as an abbreviated peer review and incomplete bibliographic access. METHODS: Seventy societies of health sciences professionals were surveyed about the publication of abstracts from their annual meetings. Nineteen frequently cited journals also were contacted about their policies on the citation of meeting abstracts. Ten databases were searched for the presence of meetings abstracts. RESULTS: Ninety percent of the seventy societies publish their abstracts, with nearly half appearing in the society's journal. Seventy-seven percent of the societies supply meeting attendees with a copy of each abstract, and 43% make their abstracts available in an electronic format. Most of the journals surveyed allow meeting abstracts to be cited. Bibliographic access to these abstracts does not appear to be widespread. CONCLUSIONS: Meeting abstracts play an important role in the dissemination of scientific knowledge. Bibliographic access to meeting abstracts is very limited. The trend toward making meeting abstracts available via the Internet has the potential to give a broader audience access to the information they contain. PMID:9549015
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.
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…
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.
Water Pollution Abstracts. Volume 43, Number 4, Abstracts 645-849.
WATER POLLUTION, *ABSTRACTS, PURIFICATION, WASTES(INDUSTRIAL), CONTROL, SEWAGE, WATER SUPPLIES, PUBLIC HEALTH, PETROLEUM PRODUCTS, DEGRADATION, DAMS...ESTUARIES, PLANKTON, PHOTOSYNTHESIS, VIRUSES, SEA WATER , MICROBIOLOGY, UNITED KINGDOM.
Reaction kinetics of hydrogen atom abstraction from isopentanol by the H atom and HO2˙ radical.
Parab, Prajakta Rajaram; Heufer, K Alexander; Fernandes, Ravi Xavier
2018-04-25
Isopentanol is a potential next-generation biofuel for future applications to Homogeneous Charge Compression Ignition (HCCI) engine concepts. To provide insights into the combustion behavior of isopentanol, especially to its auto-ignition behavior which is linked both to efficiency and pollutant formation in real combustion systems, detailed quantum chemical studies for crucial reactions are desired. H-Abstraction reaction rates from fuel molecules are key initiation steps for chain branching required for auto-ignition. In this study, rate constants are determined for the hydrogen atom abstraction reactions from isopentanol by the H atom and HO2˙ radical by implementing the CBS-QB3 composite method. For the treatment of the internal rotors, a Pitzer-Gwinn-like approximation is applied. On comparing the computed reaction energies, the highest exothermicity (ΔE = -46 kJ mol-1) is depicted for Hα abstraction by the H atom whereas the lowest endothermicity (ΔE = 29 kJ mol-1) is shown for the abstraction of Hα by the HO2˙ radical. The formation of hydrogen bonding is found to affect the kinetics of the H atom abstraction reactions by the HO2˙ radical. Further above 750 K, the calculated high pressure limit rate constants indicate that the total contribution from delta carbon sites (Cδ) is predominant for hydrogen atom abstraction by the H atom and HO2˙ radical.
The Republic of the Philippines: Background and U.S. Relations
2007-08-10
cost of living. 21 The HDI ranks countries according to human development indicators of life expectancy, education, literacy, and gross domestic...sovereignty over Mischief Reef, which is one of approximately 100 reefs and islands disputed by five Southeast Asian countries . A Visiting Forces...Order Code RL33233 The Republic of the Philippines: Background and U.S. Relations Updated August 10, 2007 Thomas Lum Specialist in Asian Affairs
Lunar Roving Vehicle photographed against lunar background during EVA
1971-08-01
AS15-88-11901 (31 July-2 Aug. 1971) --- The Lunar Roving Vehicle (LRV) is photographed alone against the desolate lunar background during the third Apollo 15 lunar surface extravehicular activity (EVA) at the Hadley-Apennine landing site. This view is looking north. The west edge of Mount Hadley is at the upper right edge of the picture. Mount Hadley rises approximately 4,500 meters (about 4,765 feet) above the plain. The most distant lunar feature visible is approximately 25 kilometers (about 15.5 statute miles) away. While astronauts David R. Scott, commander; and James B. Irwin, lunar module pilot, descended in the Lunar Module (LM) "Falcon" to explore the moon, astronaut Alfred M. Worden, command module pilot, remained with the Command and Service Modules (CSM) in lunar orbit.
Approximating a DSM-5 Diagnosis of PTSD Using DSM-IV Criteria
Rosellini, Anthony J.; Stein, Murray B.; Colpe, Lisa J.; Heeringa, Steven G.; Petukhova, Maria V.; Sampson, Nancy A.; Schoenbaum, Michael; Ursano, Robert J.; Kessler, Ronald C.
2015-01-01
Background Diagnostic criteria for DSM-5 posttraumatic stress disorder (PTSD) are in many ways similar to DSM-IV criteria, raising the possibility that it might be possible to closely approximate DSM-5 diagnoses using DSM-IV symptoms. If so, the resulting transformation rules could be used to pool research data based on the two criteria sets. Methods The Pre-Post Deployment Study (PPDS) of the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) administered a blended 30-day DSM-IV and DSM-5 PTSD symptom assessment based on the civilian PTSD Checklist for DSM-IV (PCL-C) and the PTSD Checklist for DSM-5 (PCL-5). This assessment was completed by 9,193 soldiers from three US Army Brigade Combat Teams approximately three months after returning from Afghanistan. PCL-C items were used to operationalize conservative and broad approximations of DSM-5 PTSD diagnoses. The operating characteristics of these approximations were examined compared to diagnoses based on actual DSM-5 criteria. Results The estimated 30-day prevalence of DSM-5 PTSD based on conservative (4.3%) and broad (4.7%) approximations of DSM-5 criteria using DSM-IV symptom assessments were similar to estimates based on actual DSM-5 criteria (4.6%). Both approximations had excellent sensitivity (92.6-95.5%), specificity (99.6-99.9%), total classification accuracy (99.4-99.6%), and area under the receiver operating characteristic curve (0.96-0.98). Conclusions DSM-IV symptoms can be used to approximate DSM-5 diagnoses of PTSD among recently-deployed soldiers, making it possible to recode symptom-level data from earlier DSM-IV studies to draw inferences about DSM-5 PTSD. However, replication is needed in broader trauma-exposed samples to evaluate the external validity of this finding. PMID:25845710
ERIC Educational Resources Information Center
Novak, Gordon S., Jr.
GLISP is a high-level computer language (based on Lisp and including Lisp as a sublanguage) which is compiled into Lisp. GLISP programs are compiled relative to a knowledge base of object descriptions, a form of abstract datatypes. A primary goal of the use of abstract datatypes in GLISP is to allow program code to be written in terms of objects,…
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…
Thyra Abstract Interface Package
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bartlett, Roscoe A.
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 utilities 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. Codemore » also currently exists for testing objects and providing composite objects such as product vectors.« less
Knowledge acquisition for temporal abstraction.
Stein, A; Musen, M A; Shahar, Y
1996-01-01
Temporal abstraction is the task of detecting relevant patterns in data over time. The knowledge-based temporal-abstraction method uses knowledge about a clinical domain's contexts, external events, and parameters to create meaningful interval-based abstractions from raw time-stamped clinical data. In this paper, we describe the acquisition and maintenance of domain-specific temporal-abstraction knowledge. Using the PROTEGE-II framework, we have designed a graphical tool for acquiring temporal knowledge directly from expert physicians, maintaining the knowledge in a sharable form, and converting the knowledge into a suitable format for use by an appropriate problem-solving method. In initial tests, the tool offered significant gains in our ability to rapidly acquire temporal knowledge and to use that knowledge to perform automated temporal reasoning.
A Simple and Practical Dictionary-based Approach for Identification of Proteins in Medline Abstracts
Egorov, Sergei; Yuryev, Anton; Daraselia, Nikolai
2004-01-01
Objective: The aim of this study was to develop a practical and efficient protein identification system for biomedical corpora. Design: The developed system, called ProtScan, utilizes a carefully constructed dictionary of mammalian proteins in conjunction with a specialized tokenization algorithm to identify and tag protein name occurrences in biomedical texts and also takes advantage of Medline “Name-of-Substance” (NOS) annotation. The dictionaries for ProtScan were constructed in a semi-automatic way from various public-domain sequence databases followed by an intensive expert curation step. Measurements: The recall and precision of the system have been determined using 1,000 randomly selected and hand-tagged Medline abstracts. Results: The developed system is capable of identifying protein occurrences in Medline abstracts with a 98% precision and 88% recall. It was also found to be capable of processing approximately 300 abstracts per second. Without utilization of NOS annotation, precision and recall were found to be 98.5% and 84%, respectively. Conclusion: The developed system appears to be well suited for protein-based Medline indexing and can help to improve biomedical information retrieval. Further approaches to ProtScan's recall improvement also are discussed. PMID:14764613
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)
Accounting for orphaned aftershocks in the earthquake background rate
Van Der Elst, Nicholas
2017-01-01
Aftershocks often occur within cascades of triggered seismicity in which each generation of aftershocks triggers an additional generation, and so on. The rate of earthquakes in any particular generation follows Omori's law, going approximately as 1/t. This function decays rapidly, but is heavy-tailed, and aftershock sequences may persist for long times at a rate that is difficult to discriminate from background. It is likely that some apparently spontaneous earthquakes in the observational catalogue are orphaned aftershocks of long-past main shocks. To assess the relative proportion of orphaned aftershocks in the apparent background rate, I develop an extension of the ETAS model that explicitly includes the expected contribution of orphaned aftershocks to the apparent background rate. Applying this model to California, I find that the apparent background rate can be almost entirely attributed to orphaned aftershocks, depending on the assumed duration of an aftershock sequence. This implies an earthquake cascade with a branching ratio (the average number of directly triggered aftershocks per main shock) of nearly unity. In physical terms, this implies that very few earthquakes are completely isolated from the perturbing effects of other earthquakes within the fault system. Accounting for orphaned aftershocks in the ETAS model gives more accurate estimates of the true background rate, and more realistic expectations for long-term seismicity patterns.
Accounting for orphaned aftershocks in the earthquake background rate
NASA Astrophysics Data System (ADS)
van der Elst, Nicholas J.
2017-11-01
Aftershocks often occur within cascades of triggered seismicity in which each generation of aftershocks triggers an additional generation, and so on. The rate of earthquakes in any particular generation follows Omori's law, going approximately as 1/t. This function decays rapidly, but is heavy-tailed, and aftershock sequences may persist for long times at a rate that is difficult to discriminate from background. It is likely that some apparently spontaneous earthquakes in the observational catalogue are orphaned aftershocks of long-past main shocks. To assess the relative proportion of orphaned aftershocks in the apparent background rate, I develop an extension of the ETAS model that explicitly includes the expected contribution of orphaned aftershocks to the apparent background rate. Applying this model to California, I find that the apparent background rate can be almost entirely attributed to orphaned aftershocks, depending on the assumed duration of an aftershock sequence. This implies an earthquake cascade with a branching ratio (the average number of directly triggered aftershocks per main shock) of nearly unity. In physical terms, this implies that very few earthquakes are completely isolated from the perturbing effects of other earthquakes within the fault system. Accounting for orphaned aftershocks in the ETAS model gives more accurate estimates of the true background rate, and more realistic expectations for long-term seismicity patterns.
NASA Technical Reports Server (NTRS)
Rosen, I. G.
1985-01-01
Rayleigh-Ritz methods for the approximation of the natural modes for a class of vibration problems involving flexible beams with tip bodies using subspaces of piecewise polynomial spline functions are developed. An abstract operator theoretic formulation of the eigenvalue problem is derived and spectral properties investigated. The existing theory for spline-based Rayleigh-Ritz methods applied to elliptic differential operators and the approximation properties of interpolatory splines are useed to argue convergence and establish rates of convergence. An example and numerical results are discussed.
Probing quantum entanglement in the Schwarzschild space-time beyond the single-mode approximation
NASA Astrophysics Data System (ADS)
He, Juan; Ding, Zhi-Yong; Ye, Liu
2018-05-01
In this paper, we deduce the vacuum structure for Dirac fields in the background of Schwarzschild space-time beyond the single-mode approximation and discuss the performance of quantum entanglement between particle and antiparticle modes of a Dirac field with Hawking effect. It is shown that Hawking radiation does not always destroy the physically accessible entanglement, and entanglement amplification may happen in some cases. This striking result is different from that of the single-mode approximation, which holds that the Hawking radiation can only destroy entanglement. Lastly, we analyze the physically accessible entanglement relation outside the event horizon and demonstrate that the monogamy inequality is constantly established regardless of the choice of given parameters.
2013-01-01
Background The inclusion of randomized controlled trials (RCTs) reported in conference abstracts in systematic reviews is controversial, partly because study design information and risk of bias is often not fully reported in the abstract. The Association for Research in Vision and Ophthalmology (ARVO) requires trial registration of abstracts submitted for their annual conference as of 2007. Our goal was to assess the feasibility of obtaining study design information critical to systematic reviews, but not typically included in conference abstracts, from the trial registration record. Methods We reviewed all conference abstracts presented at the ARVO meetings from 2007 through 2009, and identified 496 RCTs; 154 had a single matching registration record in ClinicalTrials.gov. Two individuals independently extracted information from the abstract and the ClinicalTrials.gov record, including study design, sample size, inclusion criteria, masking, interventions, outcomes, funder, and investigator name and contact information. Discrepancies were resolved by consensus. We assessed the frequencies of reporting variables appearing in the abstract and the trial register and assessed agreement of information reported in both sources. Results We found a substantial amount of study design information in the ClinicalTrials.gov record that was unavailable in the corresponding conference abstract, including eligibility criteria associated with gender (83%; 128/154); masking or blinding of study participants (53%, 82/154), persons administering treatment (30%, 46/154), and persons measuring the outcomes (40%, 61/154)); and number of study centers (58%; 90/154). Only 34% (52/154) of abstracts explicitly described a primary outcome, but a primary outcome was included in the “Primary Outcome” field in the ClinicalTrials.gov record for 82% (126/154) of studies. One or more study interventions were reported in each abstract, but agreed exactly with those reported in Clinical
Estimate of the cosmological bispectrum from the MAXIMA-1 cosmic microwave background map.
Santos, M G; Balbi, A; Borrill, J; Ferreira, P G; Hanany, S; Jaffe, A H; Lee, A T; Magueijo, J; Rabii, B; Richards, P L; Smoot, G F; Stompor, R; Winant, C D; Wu, J H P
2002-06-17
We use the measurement of the cosmic microwave background taken during the MAXIMA-1 flight to estimate the bispectrum of cosmological perturbations. We propose an estimator for the bispectrum that is appropriate in the flat sky approximation, apply it to the MAXIMA-1 data, and evaluate errors using bootstrap methods. We compare the estimated value with what would be expected if the sky signal were Gaussian and find that it is indeed consistent, with a chi(2) per degree of freedom of approximately unity. This measurement places constraints on models of inflation.
Genetic Background but not Metallothionein Phenotype Dictates Sensitivity to
Cadmium-Induced Testicular Injury in Mice
Jie Liu1,2, Chris Corton3, David J. Dix4, Yaping Liu1, Michael P. Waalkes2
and Curtis D. Klaassen1
ABSTRACT
Parenteral administrati...
Abstracts of contributed papers
DOE Office of Scientific and Technical Information (OSTI.GOV)
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.
Dissecting the Gamma-Ray Background in Search of Dark Matter
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cholis, Ilias; Hooper, Dan; McDermott, Samuel D.
2014-02-01
Several classes of astrophysical sources contribute to the approximately isotropic gamma-ray background measured by the Fermi Gamma-Ray Space Telescope. In this paper, we use Fermi's catalog of gamma-ray sources (along with corresponding source catalogs at infrared and radio wavelengths) to build and constrain a model for the contributions to the extragalactic gamma-ray background from astrophysical sources, including radio galaxies, star-forming galaxies, and blazars. We then combine our model with Fermi's measurement of the gamma-ray background to derive constraints on the dark matter annihilation cross section, including contributions from both extragalactic and galactic halos and subhalos. The resulting constraints are competitivemore » with the strongest current constraints from the Galactic Center and dwarf spheroidal galaxies. As Fermi continues to measure the gamma-ray emission from a greater number of astrophysical sources, it will become possible to more tightly constrain the astrophysical contributions to the extragalactic gamma-ray background. We project that with 10 years of data, Fermi's measurement of this background combined with the improved constraints on the astrophysical source contributions will yield a sensitivity to dark matter annihilations that exceeds the strongest current constraints by a factor of ~ 5 - 10.« less
Hopewell, Sally; Clarke, Mike; Moher, David; Wager, Elizabeth; Middleton, Philippa; Altman, Douglas G; Schulz, Kenneth F
2008-01-01
Background Clear, transparent, and sufficiently detailed abstracts of conferences and journal articles related to randomized controlled trials (RCTs) are important, because readers often base their assessment of a trial solely on information in the abstract. Here, we extend the CONSORT (Consolidated Standards of Reporting Trials) Statement to develop a minimum list of essential items, which authors should consider when reporting the results of a RCT in any journal or conference abstract. Methods and Findings We generated a list of items from existing quality assessment tools and empirical evidence. A three-round, modified-Delphi process was used to select items. In all, 109 participants were invited to participate in an electronic survey; the response rate was 61%. Survey results were presented at a meeting of the CONSORT Group in Montebello, Canada, January 2007, involving 26 participants, including clinical trialists, statisticians, epidemiologists, and biomedical editors. Checklist items were discussed for eligibility into the final checklist. The checklist was then revised to ensure that it reflected discussions held during and subsequent to the meeting. CONSORT for Abstracts recommends that abstracts relating to RCTs have a structured format. Items should include details of trial objectives; trial design (e.g., method of allocation, blinding/masking); trial participants (i.e., description, numbers randomized, and number analyzed); interventions intended for each randomized group and their impact on primary efficacy outcomes and harms; trial conclusions; trial registration name and number; and source of funding. We recommend the checklist be used in conjunction with this explanatory document, which includes examples of good reporting, rationale, and evidence, when available, for the inclusion of each item. Conclusions CONSORT for Abstracts aims to improve reporting of abstracts of RCTs published in journal articles and conference proceedings. It will help
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)
Abstracting and indexing guide
,; ,
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.
ERIC Educational Resources Information Center
Johns Hopkins Univ., Baltimore, MD. Center for the Study of Social Organization of Schools.
This booklet contains abstracts of 62 documents published by the Johns Hopkins University Center for the Study of Social Organization of Schools from September 1967 to May 1970. The majority of the documents are research studies in the areas of desegregation, language development, educational opportunity, and educational games--most of them…
Gandhi, Divyangkumar; Mclean, Richard W.; Laiyemo, Adeyinka O.
2017-01-01
Background/Aims Abstract presentations at scientific meetings provide an opportunity to convey the results of important research. Unfortunately, many abstracts are not eventually published as full manuscripts. We evaluated factors associated with publication of abstracts as manuscripts up to 6.5 years after presentation at the 73rd scientific meeting of the American College of Gastroenterology in 2008. Methods All abstracts, excluding case reports, presented at the meeting were evaluated. We systematically searched for matching manuscripts indexed in PubMed or EMBASE up till May 2015. We used logistic regression models to determine factors associated with manuscript publication and calculated odds ratios (OR) and 95% confidence intervals (CI). Results Of included 791 abstracts, 249 (31.5%) were published as manuscripts within 6.5 years. Oral presentation (OR=2.11; 95%CI: 1.15-3.87), multicenter studies (OR=2.67; 95%CI: 1.44-4.95), abstracts by University-based authors (OR=1.80; 95%CI: 1.20-2.72), and funded research (OR=2.15; 95%CI: 1.43-3.23) were more likely to be published. Winning an award at the meeting was not associated with manuscript publication (OR=1.09; 95%CI: 0.57-2.06). Conclusions There is an urgent need to improve dissemination of scientific knowledge through publication of abstracts presented at gastroenterology meetings as manuscripts. Mentors should endeavor to encourage their mentees to complete this final stage of their scholarly activities. PMID:27931019
NASA Technical Reports Server (NTRS)
Ito, K.
1984-01-01
The stability and convergence properties of the Legendre-tau approximation for hereditary differential systems are analyzed. A charactristic equation is derived for the eigenvalues of the resulting approximate system. As a result of this derivation the uniform exponential stability of the solution semigroup is preserved under approximation. It is the key to obtaining the convergence of approximate solutions of the algebraic Riccati equation in trace norm.
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.
A scalable moment-closure approximation for large-scale biochemical reaction networks
Kazeroonian, Atefeh; Theis, Fabian J.; Hasenauer, Jan
2017-01-01
Abstract Motivation: Stochastic molecular processes are a leading cause of cell-to-cell variability. Their dynamics are often described by continuous-time discrete-state Markov chains and simulated using stochastic simulation algorithms. As these stochastic simulations are computationally demanding, ordinary differential equation models for the dynamics of the statistical moments have been developed. The number of state variables of these approximating models, however, grows at least quadratically with the number of biochemical species. This limits their application to small- and medium-sized processes. Results: In this article, we present a scalable moment-closure approximation (sMA) for the simulation of statistical moments of large-scale stochastic processes. The sMA exploits the structure of the biochemical reaction network to reduce the covariance matrix. We prove that sMA yields approximating models whose number of state variables depends predominantly on local properties, i.e. the average node degree of the reaction network, instead of the overall network size. The resulting complexity reduction is assessed by studying a range of medium- and large-scale biochemical reaction networks. To evaluate the approximation accuracy and the improvement in computational efficiency, we study models for JAK2/STAT5 signalling and NFκB signalling. Our method is applicable to generic biochemical reaction networks and we provide an implementation, including an SBML interface, which renders the sMA easily accessible. Availability and implementation: The sMA is implemented in the open-source MATLAB toolbox CERENA and is available from https://github.com/CERENADevelopers/CERENA. Contact: jan.hasenauer@helmholtz-muenchen.de or atefeh.kazeroonian@tum.de Supplementary information: Supplementary data are available at Bioinformatics online. PMID:28881983
SEER Abstracting Tool (SEER*Abs)
With this customizable tool, registrars can collect and store data abstracted from medical records. Download the software and find technical support and reference manuals. SEER*Abs has features for creating records, managing abstracting work and data, accessing reference data, and integrating edits.
The Abstraction Process of Limit Knowledge
ERIC Educational Resources Information Center
Sezgin Memnun, Dilek; Aydin, Bünyamin; Özbilen, Ömer; Erdogan, Günes
2017-01-01
The RBC+C abstraction model is an effective model in mathematics education because it gives the opportunity to analyze research data through cognitive actions. For this reason, we aim to examine the abstraction process of the limit knowledge of two volunteer participant students using the RBC+C abstraction model. With this aim, the students'…
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.
Abstracts of Research Papers 1970.
ERIC Educational Resources Information Center
Drowatzky, John N., Ed.
This publication includes the abstracts of 199 research papers presented at the 1970 American Association for Health, Physical Education, and Recreation convention in Seattle, Washington. Abstracts from symposia on environmental quality education, obesity, motor development, research methods, and laboratory equipment are also included. Each…
Effects of Background Noise on Cortical Encoding of Speech in Autism Spectrum Disorders
ERIC Educational Resources Information Center
Russo, Nicole; Zecker, Steven; Trommer, Barbara; Chen, Julia; Kraus, Nina
2009-01-01
This study provides new evidence of deficient auditory cortical processing of speech in noise in autism spectrum disorders (ASD). Speech-evoked responses (approximately 100-300 ms) in quiet and background noise were evaluated in typically-developing (TD) children and children with ASD. ASD responses showed delayed timing (both conditions) and…
CONTRIBUTIONS TO RATIONAL APPROXIMATION,
Some of the key results of linear Chebyshev approximation theory are extended to generalized rational functions. Prominent among these is Haar’s...linear theorem which yields necessary and sufficient conditions for uniqueness. Some new results in the classic field of rational function Chebyshev...Furthermore a Weierstrass type theorem is proven for rational Chebyshev approximation. A characterization theorem for rational trigonometric Chebyshev approximation in terms of sign alternation is developed. (Author)
Kinetics of Hydrogen Abstraction and Addition Reactions of 3-Hexene by ȮH Radicals.
Yang, Feiyu; Deng, Fuquan; Pan, Youshun; Zhang, Yingjia; Tang, Chenglong; Huang, Zuohua
2017-03-09
Rate coefficients of H atom abstraction and H atom addition reactions of 3-hexene by the hydroxyl radicals were determined using both conventional transition-state theory and canonical variational transition-state theory, with the potential energy surface (PES) evaluated at the CCSD(T)/CBS//BHandHLYP/6-311G(d,p) level and quantum mechanical effect corrected by the compounded methods including one-dimensional Wigner method, multidimensional zero-curvature tunneling method, and small-curvature tunneling method. Results reveal that accounting for approximate 70% of the overall H atom abstractions occur in the allylic site via both direct and indirect channels. The indirect channel containing two van der Waals prereactive complexes exhibits two times larger rate coefficient relative to the direct one. The OH addition reaction also contains two van der Waals complexes, and its submerged barrier results in a negative temperature coefficient behavior at low temperatures. In contrast, The OH addition pathway dominates only at temperatures below 450 K whereas the H atom abstraction reactions dominate overwhelmingly at temperature over 1000 K. All of the rate coefficients calculated with an uncertainty of a factor of 5 were fitted in a quasi-Arrhenius formula. Analyses on the PES, minimum reaction path and activation free Gibbs energy were also performed in this study.
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)
Smith, Heather D.; Bogenschutz, Elizabeth D.; Bayliss, Amy J.; Altenburger, Peter A.
2011-01-01
Background and Objective Professional meetings, such as the American Physical Therapy Association's (APTA's) Combined Sections Meeting (CSM), provide forums for sharing information relevant to physical therapy. An indicator of whether therapists fully disseminate their work is the number of full-text peer-reviewed publications that result. The purposes of this study were: (1) to determine the full-text publication rate of work presented in abstract form at CSM and (2) to investigate factors influencing this rate. Methods A systematic search was undertaken to locate full-text publications of work presented in abstract form within the Orthopaedic and Sports Physical Therapy sections at CSM between 2000 and 2004. Eligible publications were published within 5 years following abstract presentation. The influences of APTA section, year of abstract presentation, institution of origin, study design, sample size, study significance, reporting of a funding source, and presentation type on full-text publication rate were assessed. Characteristics of full-text publications were explored. Results Work presented in 1 out of 4 abstracts (25.4%) progressed to full-text publication. Odds of full-text publication increased if the abstract originated from a doctorate-granting or “other” institution, reported findings of an experimental study, reported a statistically significant finding, included a larger sample size, disclosed a funding source, or was presented as a platform presentation. More than one third (37.8%) of full-text publications were published in the Journal of Orthopaedic and Sports Physical Therapy or Physical Therapy, and 4 out of 10 full-text publications (39.2%) contained at least one major change from information presented in abstract form. Conclusions The full-text publication rate for information presented in abstract form within the Orthopaedic and Sports Physical Therapy sections at CSM is low relative to comparative disciplines. Caution should be
Binarization algorithm for document image with complex background
NASA Astrophysics Data System (ADS)
Miao, Shaojun; Lu, Tongwei; Min, Feng
2015-12-01
The most important step in image preprocessing for Optical Character Recognition (OCR) is binarization. Due to the complex background or varying light in the text image, binarization is a very difficult problem. This paper presents the improved binarization algorithm. The algorithm can be divided into several steps. First, the background approximation can be obtained by the polynomial fitting, and the text is sharpened by using bilateral filter. Second, the image contrast compensation is done to reduce the impact of light and improve contrast of the original image. Third, the first derivative of the pixels in the compensated image are calculated to get the average value of the threshold, then the edge detection is obtained. Fourth, the stroke width of the text is estimated through a measuring of distance between edge pixels. The final stroke width is determined by choosing the most frequent distance in the histogram. Fifth, according to the value of the final stroke width, the window size is calculated, then a local threshold estimation approach can begin to binaries the image. Finally, the small noise is removed based on the morphological operators. The experimental result shows that the proposed method can effectively remove the noise caused by complex background and varying light.
Innovation Abstracts; Volume XIV, 1992.
ERIC Educational Resources Information Center
Roueche, Suanne D., Ed.
1992-01-01
This series of 30 one- to two-page abstracts covering 1992 highlights a variety of innovative approaches to teaching and learning in the community college. Topics covered in the abstracts include: (1) faculty recognition and orientation; (2) the Amado M. Pena, Jr., Scholarship Program; (3) innovative teaching techniques, with individual abstracts…
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…
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…
A cosmic microwave background feature consistent with a cosmic texture.
Cruz, M; Turok, N; Vielva, P; Martínez-González, E; Hobson, M
2007-12-07
The Cosmic Microwave Background provides our most ancient image of the universe and our best tool for studying its early evolution. Theories of high-energy physics predict the formation of various types of topological defects in the very early universe, including cosmic texture, which would generate hot and cold spots in the Cosmic Microwave Background. We show through a Bayesian statistical analysis that the most prominent 5 degrees -radius cold spot observed in all-sky images, which is otherwise hard to explain, is compatible with having being caused by a texture. From this model, we constrain the fundamental symmetry-breaking energy scale to be (0) approximately 8.7 x 10(15) gigaelectron volts. If confirmed, this detection of a cosmic defect will probe physics at energies exceeding any conceivable terrestrial experiment.
NASA Astrophysics Data System (ADS)
Aleksandrov, A. P.; Berezovoy, A. N.; Galper, A. M.; Grachev, V. M.; Dmitrenko, V. V.; Kirillov-Ugryumov, V. G.; Lebedev, V. V.; Lyakhov, V. A.; Moiseyev, A. A.; Ulin, S. Y.
1985-09-01
Coding collimators are used to improve the angular resolution of gamma-ray telescopes at energies above 50 MeV. However, the interaction of cosmic rays with the collimation material can lead to the appearance of a gamma-ray background flux which can have a deleterious effect on measurement efficiency. An experiment was performed on the Salyut-6-Soyuz spacecraft system with the Elena-F small-scale gamma-ray telescope in order to measure the magnitude of this background. It is shown that, even at a zenith angle of approximately zero degrees (the angle at which the gamma-ray observations are made), the coding collimator has only an insignificant effect on the background conditions.
Approximate kernel competitive learning.
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. Copyright © 2014 Elsevier Ltd. All rights reserved.
Refining a taxonomy for guideline implementation: results of an exercise in abstract classification.
Mazza, Danielle; Bairstow, Phillip; Buchan, Heather; Chakraborty, Samantha Paubrey; Van Hecke, Oliver; Grech, Cathy; Kunnamo, Ilkka
2013-03-15
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. 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. 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). 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.
Innovation Abstracts, Volume XVI, 1994.
ERIC Educational Resources Information Center
Roueche, Suanne D., Ed.
1994-01-01
This volume of 30 one- to two-page abstracts highlights a variety of innovative approaches to teaching and learning in the community college. Topics covered in the abstracts include: (1) music in the biology classroom; (2) pairing English as a second language and freshman composition students in writing activities; (3) moot court exercises in…
A grounded theory of abstraction in artificial intelligence.
Zucker, Jean-Daniel
2003-01-01
In artificial intelligence, abstraction is commonly used to account for the use of various levels of details in a given representation language or the ability to change from one level to another while preserving useful properties. Abstraction has been mainly studied in problem solving, theorem proving, knowledge representation (in particular for spatial and temporal reasoning) and machine learning. In such contexts, abstraction is defined as a mapping between formalisms that reduces the computational complexity of the task at stake. By analysing the notion of abstraction from an information quantity point of view, we pinpoint the differences and the complementary role of reformulation and abstraction in any representation change. We contribute to extending the existing semantic theories of abstraction to be grounded on perception, where the notion of information quantity is easier to characterize formally. In the author's view, abstraction is best represented using abstraction operators, as they provide semantics for classifying different abstractions and support the automation of representation changes. The usefulness of a grounded theory of abstraction in the cartography domain is illustrated. Finally, the importance of explicitly representing abstraction for designing more autonomous and adaptive systems is discussed. PMID:12903672
A grounded theory of abstraction in artificial intelligence.
Zucker, Jean-Daniel
2003-07-29
In artificial intelligence, abstraction is commonly used to account for the use of various levels of details in a given representation language or the ability to change from one level to another while preserving useful properties. Abstraction has been mainly studied in problem solving, theorem proving, knowledge representation (in particular for spatial and temporal reasoning) and machine learning. In such contexts, abstraction is defined as a mapping between formalisms that reduces the computational complexity of the task at stake. By analysing the notion of abstraction from an information quantity point of view, we pinpoint the differences and the complementary role of reformulation and abstraction in any representation change. We contribute to extending the existing semantic theories of abstraction to be grounded on perception, where the notion of information quantity is easier to characterize formally. In the author's view, abstraction is best represented using abstraction operators, as they provide semantics for classifying different abstractions and support the automation of representation changes. The usefulness of a grounded theory of abstraction in the cartography domain is illustrated. Finally, the importance of explicitly representing abstraction for designing more autonomous and adaptive systems is discussed.
First Intrinsic Anisotropy Observations With the Cosmic Background Imager
NASA Technical Reports Server (NTRS)
Padin, S.; Cartwright, J. K.; Mason, B. S.; Pearson, T. J.; Readhead, A. C. S.; Shepherd, M. C.; Sievers, J.; Udomprasert, P. S.; Holzapfel, W. L.; Myers, S. T.;
2001-01-01
We present the first results of observations of the intrinsic anisotropy of the cosmic microwave background radiation with the Cosmic Background Imager from a site at 5080 in altitude in northern Chile. Our observations show a sharp decrease in C_l in the range l = 400 - 1500. Such a decrease in power at high l is one of the fundamental predictions of the standard cosmological model, and these are the first observations which cover a broad enough 1-range to show this decrease in a single experiment. The power, C_l, at l approximately 600 is higher than measured by Boomerang and Maxima, with the differences being significant at the 2.7sigma and 1.9sigma levels, respectively. The C_l we have measured enable us to place limits on the density parameter, Omega(tot) <= 0.4 or Omega(tot) >= 0.7 (90% confidence).
Higgs effective potential in a perturbed Robertson-Walker background
NASA Astrophysics Data System (ADS)
Maroto, Antonio L.; Prada, Francisco
2014-12-01
We calculate the one-loop effective potential of a scalar field in a Robertson-Walker background with scalar metric perturbations. A complete set of orthonormal solutions of the perturbed equations is obtained by using the adiabatic approximation for comoving observers. After analyzing the problem of renormalization in inhomogeneous backgrounds, we get the explicit contribution of metric perturbations to the effective potential. We apply these results to the Standard Model Higgs field and evaluate the effects of metric perturbations on the Higgs mass and on its vacuum expectation value. Space-time variations are found, which are proportional to the gravitational slip parameter, with a typical amplitude of the order of Δ ϕ /ϕ ≃10-11 on cosmological scales. We also discuss possible astrophysical signatures in the Solar System and in the Milky Way that could open new possibilities to explore the symmetry breaking sector of the electroweak interactions.
Abstract Spatial Reasoning as an Autistic Strength
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
Dim target trajectory-associated detection in bright earth limb background
NASA Astrophysics Data System (ADS)
Chen, Penghui; Xu, Xiaojian; He, Xiaoyu; Jiang, Yuesong
2015-09-01
The intensive emission of earth limb in the field of view of sensors contributes much to the observation images. Due to the low signal-to-noise ratio (SNR), it is a challenge to detect small targets in earth limb background, especially for the detection of point-like targets from a single frame. To improve the target detection, track before detection (TBD) based on the frame sequence is performed. In this paper, a new technique is proposed to determine the target associated trajectories, which jointly carries out background removing, maximum value projection (MVP) and Hough transform. The background of the bright earth limb in the observation images is removed according to the profile characteristics. For a moving target, the corresponding pixels in the MVP image are shifting approximately regularly in time sequence. And the target trajectory is determined by Hough transform according to the pixel characteristics of the target and the clutter and noise. Comparing with traditional frame-by-frame methods, determining associated trajectories from MVP reduces the computation load. Numerical simulations are presented to demonstrate the effectiveness of the approach proposed.
NASA Technical Reports Server (NTRS)
Mashhoon, B.
1982-01-01
The influence of a stochastic and isotropic background of gravitational radiation on timing measurements of pulsars is investigated, and it is shown that pulsar timing noise may be used to establish a significant upper limit of about 10 to the -10th on the total energy density of very long-wavelength stochastic gravitational waves. This places restriction on the strength of very long wavelength gravitational waves in the Friedmann model, and such a background is expected to have no significant effect on the approximately 3 K electromagnetic background radiation or on the dynamics of a cluster of galaxies.
A method of reducing background fluctuation in tunable diode laser absorption spectroscopy
NASA Astrophysics Data System (ADS)
Yang, Rendi; Dong, Xiaozhou; Bi, Yunfeng; Lv, Tieliang
2018-03-01
Optical interference fringe is the main factor that leads to background fluctuation in gas concentration detection based on tunable diode laser absorption spectroscopy. The interference fringes are generated by multiple reflections or scatterings upon optical surfaces in optical path and make the background signal present an approximated sinusoidal oscillation. To reduce the fluctuation of the background, a method that combines dual tone modulation (DTM) with vibration reflector (VR) is proposed in this paper. The combination of DTM and VR can make the unwanted periodic interference fringes to be averaged out and the effectiveness of the method in reducing background fluctuation has been verified by simulation and real experiments in this paper. In the detection system based on the proposed method, the standard deviation (STD) value of the background signal is decreased to 0.0924 parts per million (ppm), which is reduced by a factor of 16 compared with that of wavelength modulation spectroscopy. The STD value of 0.0924 ppm corresponds to the absorption of 4 . 328 × 10-6Hz - 1 / 2 (with effective optical path length of 4 m and integral time of 0.1 s). Moreover, the proposed method presents a better stable performance in reducing background fluctuation in long time experiments.
Scherer, Roberta W.; Huynh, Lynn; Ervin, Ann-Margret; Dickersin, Kay
2015-01-01
Background Including results from unpublished randomized controlled trials (RCTs) in a systematic review may ameliorate the effect of publication bias in systematic review results. Unpublished RCTs are sometimes described in abstracts presented at conferences, included in trials registers, or both. Trial results may not be available in a trials register and abstracts describing RCT results often lack study design information. Complementary information from a trials register record may be sufficient to allow reliable inclusion of an unpublished RCT only available as an abstract in a systematic review. Methods We identified 496 abstracts describing RCTs presented at the 2007 to 2009 Association for Research in Vision and Ophthalmology (ARVO) meetings; 154 RCTs were registered in ClinicalTrials.gov. Two persons extracted verbatim primary and non-primary outcomes reported in the abstract and ClinicalTrials.gov record. We compared each abstract outcome with all ClinicalTrials.gov outcomes and coded matches as complete, partial, or no match. Results We identified 800 outcomes in 152 abstracts (95 primary [51 abstracts] and 705 [141 abstracts] non-primary outcomes). No outcomes were reported in 2 abstracts. Of 95 primary outcomes, 17 (18%) agreed completely, 53 (56%) partially, and 25 (26%) had no match with a ClinicalTrials.gov primary or non-primary outcome. Among 705 non-primary outcomes, 56 (8%) agreed completely, 205 (29%) agreed partially, and 444 (63%) had no match with a ClinicalTrials.gov primary or non-primary outcome. Among the 258 outcomes partially agreeing, we found additional information on the time when the outcome was measured more often in ClinicalTrials.gov than in the abstract (141/258 (55%) versus 55/258 (21%)). We found no association between the presence of non-matching “new” outcomes and year of registration, time to registry update, industry sponsorship, or multi-center status. Conclusion Conference abstracts may be a valuable source of
Construct Abstraction for Automatic Information Abstraction from Digital Images
2006-05-30
objects and features and the names of objects of objects and features. For example, in Figure 15 the parts of the fish could be named the ‘mouth... fish -1 fish -2 fish -3 tennis shoe tennis racquet...of abstraction and generality. For example, an algorithm might usefully find a polygon ( blob ) in an image and calculate numbers such as the
Tips to Understanding and Writing Manuscript Abstracts
ERIC Educational Resources Information Center
Plakhotnik, Maria S.
2017-01-01
An abstract represents a short summary of key elements of the manuscript. The purpose of this essay is to discuss the function, contents, and types of manuscript abstracts. The essay concludes with a few tips for authors to writing effective abstracts.
Saldanha, Ian J; Schmid, Christopher H; Lau, Joseph; Dickersin, Kay; Berlin, Jesse A; Jap, Jens; Smith, Bryant T; Carini, Simona; Chan, Wiley; De Bruijn, Berry; Wallace, Byron C; Hutfless, Susan M; Sim, Ida; Murad, M Hassan; Walsh, Sandra A; Whamond, Elizabeth J; Li, Tianjing
2016-11-22
Data abstraction, a critical systematic review step, is time-consuming and prone to errors. Current standards for approaches to data abstraction rest on a weak evidence base. We developed the Data Abstraction Assistant (DAA), a novel software application designed to facilitate the abstraction process by allowing users to (1) view study article PDFs juxtaposed to electronic data abstraction forms linked to a data abstraction system, (2) highlight (or "pin") the location of the text in the PDF, and (3) copy relevant text from the PDF into the form. We describe the design of a randomized controlled trial (RCT) that compares the relative effectiveness of (A) DAA-facilitated single abstraction plus verification by a second person, (B) traditional (non-DAA-facilitated) single abstraction plus verification by a second person, and (C) traditional independent dual abstraction plus adjudication to ascertain the accuracy and efficiency of abstraction. This is an online, randomized, three-arm, crossover trial. We will enroll 24 pairs of abstractors (i.e., sample size is 48 participants), each pair comprising one less and one more experienced abstractor. Pairs will be randomized to abstract data from six articles, two under each of the three approaches. Abstractors will complete pre-tested data abstraction forms using the Systematic Review Data Repository (SRDR), an online data abstraction system. The primary outcomes are (1) proportion of data items abstracted that constitute an error (compared with an answer key) and (2) total time taken to complete abstraction (by two abstractors in the pair, including verification and/or adjudication). The DAA trial uses a practical design to test a novel software application as a tool to help improve the accuracy and efficiency of the data abstraction process during systematic reviews. Findings from the DAA trial will provide much-needed evidence to strengthen current recommendations for data abstraction approaches. The trial is registered
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.
Cosmological applications of Padé approximant
NASA Astrophysics Data System (ADS)
Wei, Hao; Yan, Xiao-Peng; Zhou, Ya-Nan
2014-01-01
As is well known, in mathematics, any function could be approximated by the Padé approximant. The Padé approximant is the best approximation of a function by a rational function of given order. In fact, the Padé approximant often gives better approximation of the function than truncating its Taylor series, and it may still work where the Taylor series does not converge. In the present work, we consider the Padé approximant in two issues. First, we obtain the analytical approximation of the luminosity distance for the flat XCDM model, and find that the relative error is fairly small. Second, we propose several parameterizations for the equation-of-state parameter (EoS) of dark energy based on the Padé approximant. They are well motivated from the mathematical and physical points of view. We confront these EoS parameterizations with the latest observational data, and find that they can work well. In these practices, we show that the Padé approximant could be an useful tool in cosmology, and it deserves further investigation.
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…
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)
Multi-terminology indexing for the assignment of MeSH descriptors to medical abstracts in French
Pereira, Suzanne; Sakji, Saoussen; Névéol, Aurélie; Kergourlay, Ivan; Kerdelhué, Gaétan; Serrot, Elisabeth; Joubert, Michel; Darmoni, Stéfan J.
2009-01-01
Background: To facilitate information retrieval in the biomedical domain, a system for the automatic assignment of Medical Subject Headings to documents curated by an online quality-controlled health gateway was implemented. The French Multi-Terminology Indexer (F-MTI) implements a multiterminology approach using nine main medical terminologies in French and the mappings between them. Objective: This paper presents recent efforts to assess the added value of (a) integrating four new terminologies (Orphanet, ATC, drug names, MeSH supplementary concepts) into F-MTI’s knowledge sources and (b) performing the automatic indexing on the titles and abstracts (vs. title only) of the online health resources. Methods: F-MTI was evaluated on a CISMeF corpus comprising 18,161 manually indexed resources. Results: The performance of F-MTI including nine health terminologies on CISMeF resources with Title only was 27.9% precision and 19.7% recall, while the performance on CISMeF resources with Title and Abstract is 14.9 % precision (−13.0%) and 25.9% recall (+6.2%). Conclusion: In a few weeks, CISMeF will launch the indexing of resources based on title and abstract, using nine terminologies. PMID:20351910
Odic, Darko; Lisboa, Juan Valle; Eisinger, Robert; Olivera, Magdalena Gonzalez; Maiche, Alejandro; Halberda, Justin
2016-01-01
What is the relationship between our intuitive sense of number (e.g., when estimating how many marbles are in a jar), and our intuitive sense of other quantities, including time (e.g., when estimating how long it has been since we last ate breakfast)? Recent work in cognitive, developmental, comparative psychology, and computational neuroscience has suggested that our representations of approximate number, time, and spatial extent are fundamentally linked and constitute a "generalized magnitude system". But, the shared behavioral and neural signatures between number, time, and space may alternatively be due to similar encoding and decision-making processes, rather than due to shared domain-general representations. In this study, we investigate the relationship between approximate number and time in a large sample of 6-8 year-old children in Uruguay by examining how individual differences in the precision of number and time estimation correlate with school mathematics performance. Over four testing days, each child completed an approximate number discrimination task, an approximate time discrimination task, a digit span task, and a large battery of symbolic math tests. We replicate previous reports showing that symbolic math abilities correlate with approximate number precision and extend those findings by showing that math abilities also correlate with approximate time precision. But, contrary to approximate number and time sharing common representations, we find that each of these dimensions uniquely correlates with formal math: approximate number correlates more strongly with formal math compared to time and continues to correlate with math even when precision in time and individual differences in working memory are controlled for. These results suggest that there are important differences in the mental representations of approximate number and approximate time and further clarify the relationship between quantity representations and mathematics. Copyright
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.
NASA Technical Reports Server (NTRS)
Tilton, James C.; Cook, Diane J.
2008-01-01
Under a project recently selected for funding by NASA's Science Mission Directorate under the Applied Information Systems Research (AISR) program, Tilton and Cook will design and implement the integration of the Subdue graph based knowledge discovery system, developed at the University of Texas Arlington and Washington State University, with image segmentation hierarchies produced by the RHSEG software, developed at NASA GSFC, and perform pilot demonstration studies of data analysis, mining and knowledge discovery on NASA data. Subdue represents a method for discovering substructures in structural databases. Subdue is devised for general-purpose automated discovery, concept learning, and hierarchical clustering, with or without domain knowledge. Subdue was developed by Cook and her colleague, Lawrence B. Holder. For Subdue to be effective in finding patterns in imagery data, the data must be abstracted up from the pixel domain. An appropriate abstraction of imagery data is a segmentation hierarchy: a set of several segmentations of the same image at different levels of detail in which the segmentations at coarser levels of detail can be produced from simple merges of regions at finer levels of detail. The RHSEG program, a recursive approximation to a Hierarchical Segmentation approach (HSEG), can produce segmentation hierarchies quickly and effectively for a wide variety of images. RHSEG and HSEG were developed at NASA GSFC by Tilton. In this presentation we provide background on the RHSEG and Subdue technologies and present a preliminary analysis on how RHSEG and Subdue may be combined to enhance image data analysis, mining and knowledge discovery.
Cosmic microwave background bispectrum from primordial magnetic fields on large angular scales.
Seshadri, T R; Subramanian, Kandaswamy
2009-08-21
Primordial magnetic fields lead to non-Gaussian signals in the cosmic microwave background (CMB) even at the lowest order, as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. In contrast, CMB non-Gaussianity due to inflationary scalar perturbations arises only as a higher-order effect. We propose a novel probe of stochastic primordial magnetic fields that exploits the characteristic CMB non-Gaussianity that they induce. We compute the CMB bispectrum (b(l1l2l3)) induced by such fields on large angular scales. We find a typical value of l1(l1 + 1)l3(l3 + 1)b(l1l2l3) approximately 10(-22), for magnetic fields of strength B0 approximately 3 nG and with a nearly scale invariant magnetic spectrum. Observational limits on the bispectrum allow us to set upper limits on B0 approximately 35 nG.
Neural dynamic optimization for control systems. I. Background.
Seong, C Y; Widrow, B
2001-01-01
The paper presents neural dynamic optimization (NDO) as a method of optimal feedback control for nonlinear multi-input-multi-output (MIMO) systems. The main feature of NDO is that it enables neural networks to approximate the optimal feedback solution whose existence dynamic programming (DP) justifies, thereby reducing the complexities of computation and storage problems of the classical methods such as DP. This paper mainly describes the background and motivations for the development of NDO, while the two other subsequent papers of this topic present the theory of NDO and demonstrate the method with several applications including control of autonomous vehicles and of a robot arm, respectively.
Cosmic microwave background radiation anisotropies in brane worlds.
Koyama, Kazuya
2003-11-28
We propose a new formulation to calculate the cosmic microwave background (CMB) spectrum in the Randall-Sundrum two-brane model based on recent progress in solving the bulk geometry using a low energy approximation. The evolution of the anisotropic stress imprinted on the brane by the 5D Weyl tensor is calculated. An impact of the dark radiation perturbation on the CMB spectrum is investigated in a simple model assuming an initially scale-invariant adiabatic perturbation. The dark radiation perturbation induces isocurvature perturbations, but the resultant spectrum can be quite different from the prediction of simple mixtures of adiabatic and isocurvature perturbations due to Weyl anisotropic stress.
Abstracting/Annotating. ERIC Processing Manual, Section VI.
ERIC Educational Resources Information Center
Brandhorst, Ted, Ed.
Rules and guidelines are provided for the preparation of abstracts and annotations for documents and journal articles entering the ERIC database. Various types of abstracts are defined, including the Informative, Indicative, and mixed Informative-Indicative. Advice is given on how to select the abstract type appropriate for the particular…
Leptogenesis from heavy right-handed neutrinos in CPT violating backgrounds
NASA Astrophysics Data System (ADS)
Bossingham, Thomas; Mavromatos, Nick E.; Sarkar, Sarben
2018-02-01
We discuss leptogenesis in a model with heavy right-handed Majorana neutrinos propagating in a constant but otherwise generic CPT-violating axial time-like background (motivated by string theory). At temperatures much higher than the temperature of the electroweak phase transition, we solve approximately, but analytically (using Padé approximants), the corresponding Boltzmann equations, which describe the generation of lepton asymmetry from the tree-level decays of heavy neutrinos into Standard Model leptons. At such temperatures these leptons are effectively massless. The current work completes in a rigorous way a preliminary treatment of the same system, by some of the present authors. In this earlier work, lepton asymmetry was crudely estimated considering the decay of a right-handed neutrino at rest. Our present analysis includes thermal momentum modes for the heavy neutrino and this leads to a total lepton asymmetry which is bigger by a factor of two as compared to the previous estimate. Nevertheless, our current and preliminary results for the freezeout are found to be in agreement (within a ˜ 12.5% uncertainty). Our analysis depends on a novel use of Padé approximants to solve the Boltzmann equations and may be more widely useful in cosmology.
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.
ABSTRACTS OF RESEARCH REPORTS.
DENTISTRY, ABSTRACTS), TEETH, DISEASES, MOUTH, TRANSPLANTATION, HYGIENE, STERILIZATION, FLUORIDES, HISTOLOGY, SURGICAL IMPLANTATION, OXYTETRACYCLINE , GELATINS, CELLULOSE, CASTING, PROGRAMMED INSTRUCTION, TRAINING DEVICES
Abstractions for Fault-Tolerant Distributed System Verification
NASA Technical Reports Server (NTRS)
Pike, Lee S.; Maddalon, Jeffrey M.; Miner, Paul S.; Geser, Alfons
2004-01-01
Four kinds of abstraction for the design and analysis of fault tolerant distributed systems are discussed. These abstractions concern system messages, faults, fault masking voting, and communication. The abstractions are formalized in higher order logic, and are intended to facilitate specifying and verifying such systems in higher order theorem provers.
Sleight, C C; Prinz, P M
1985-11-01
In this study language-disordered and nondisordered children viewed a nonverbal film, wrote the story, and narrated it to language-disordered and nondisordered peers who were unfamiliar with the film. The narratives were analyzed for the use of abstracts, orientations (background information), and codas. Language-disordered children made fewer references to the orientation clauses of props and activities than nondisordered children. Neither group modified their language in the areas examined to take into account the communicative status of their listeners. Therapeutic implications for the language-disordered children are presented as are suggestions for future research.
ERIC Educational Resources Information Center
Cresswell, John
2004-01-01
The primary focus of this report is to examine the effect that immigrant status and home language background may have on the performance of Australian students who participated in the OECD/Programme for International Student Assessment (PISA 2000). Approximately 5,477 students from 231 schools across Australia participated in the study. In this…
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.
Abstraction and model evaluation in category learning.
Vanpaemel, Wolf; Storms, Gert
2010-05-01
Thirty previously published data sets, from seminal category learning tasks, are reanalyzed using the varying abstraction model (VAM). Unlike a prototype-versus-exemplar analysis, which focuses on extreme levels of abstraction only, a VAM analysis also considers the possibility of partial abstraction. Whereas most data sets support no abstraction when only the extreme possibilities are considered, we show that evidence for abstraction can be provided using the broader view on abstraction provided by the VAM. The present results generalize earlier demonstrations of partial abstraction (Vanpaemel & Storms, 2008), in which only a small number of data sets was analyzed. Following the dominant modus operandi in category learning research, Vanpaemel and Storms evaluated the models on their best fit, a practice known to ignore the complexity of the models under consideration. In the present study, in contrast, model evaluation not only relies on the maximal likelihood, but also on the marginal likelihood, which is sensitive to model complexity. Finally, using a large recovery study, it is demonstrated that, across the 30 data sets, complexity differences between the models in the VAM family are small. This indicates that a (computationally challenging) complexity-sensitive model evaluation method is uncalled for, and that the use of a (computationally straightforward) complexity-insensitive model evaluation method is justified.
Planets as background noise sources in free space optical communications
NASA Technical Reports Server (NTRS)
Katz, J.
1986-01-01
Background noise generated by planets is the dominant noise source in most deep space direct detection optical communications systems. Earlier approximate analyses of this problem are based on simplified blackbody calculations and can yield results that may be inaccurate by up to an order of magnitude. Various other factors that need to be taken into consideration, such as the phase angle and the actual spectral dependence of the planet albedo, in order to obtain a more accurate estimate of the noise magnitude are examined.
Bounded-Degree Approximations of Stochastic Networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quinn, Christopher J.; Pinar, Ali; Kiyavash, Negar
2017-06-01
We propose algorithms to approximate directed information graphs. Directed information graphs are probabilistic graphical models that depict causal dependencies between stochastic processes in a network. The proposed algorithms identify optimal and near-optimal approximations in terms of Kullback-Leibler divergence. The user-chosen sparsity trades off the quality of the approximation against visual conciseness and computational tractability. One class of approximations contains graphs with speci ed in-degrees. Another class additionally requires that the graph is connected. For both classes, we propose algorithms to identify the optimal approximations and also near-optimal approximations, using a novel relaxation of submodularity. We also propose algorithms to identifymore » the r-best approximations among these classes, enabling robust decision making.« less
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…
Limitations of shallow nets approximation.
Lin, Shao-Bo
2017-10-01
In this paper, we aim at analyzing the approximation abilities of shallow networks in reproducing kernel Hilbert spaces (RKHSs). We prove that there is a probability measure such that the achievable lower bound for approximating by shallow nets can be realized for all functions in balls of reproducing kernel Hilbert space with high probability, which is different with the classical minimax approximation error estimates. This result together with the existing approximation results for deep nets shows the limitations for shallow nets and provides a theoretical explanation on why deep nets perform better than shallow nets. Copyright © 2017 Elsevier Ltd. All rights reserved.
Innermost stable circular orbit of spinning particle in charged spinning black hole background
NASA Astrophysics Data System (ADS)
Zhang, Yu-Peng; Wei, Shao-Wen; Guo, Wen-Di; Sui, Tao-Tao; Liu, Yu-Xiao
2018-04-01
In this paper we investigate the innermost stable circular orbit (ISCO) (spin-aligned or anti-aligned orbit) for a classical spinning test particle with the pole-dipole approximation in the background of Kerr-Newman black hole in the equatorial plane. It is shown that the orbit of the spinning particle is related to the spin of the test particle. The motion of the spinning test particle will be superluminal if its spin is too large. We give an additional condition by considering the superluminal constraint for the ISCO in the black hole backgrounds. We obtain numerically the relations between the ISCO and the properties of the black holes and the test particle. It is found that the radius of the ISCO for a spinning test particle is smaller than that of a nonspinning test particle in the black hole backgrounds.
Cosmic microwave background dipole spectrum measured by the COBE FIRAS instrument
NASA Technical Reports Server (NTRS)
Fixsen, D. J.; Cheng, E. S.; Cottingham, D. A.; Eplee, R. E., Jr.; Isaacman, R. B.; Mather, J. C.; Meyer, S. S.; Noerdlinger, P. D.; Shafer, R. A.; Weiss, R.
1994-01-01
The Far-Infrared Absolute Spectrophotometer (FIRAS) instrument on the Cosmic Background Explorer (COBE) has determined the dipole spectrum of the cosmic microwave background radiation (CMBR) from 2 to 20/cm. For each frequency the signal is decomposed by fitting to a monopole, a dipole, and a Galactic template for approximately 60% of the sky. The overall dipole spectrum fits the derivative of a Planck function with an amplitude of 3.343 +/- 0.016 mK (95% confidence level), a temperature of 2.714 +/- 0.022 K (95% confidence level), and an rms deviation of 6 x 10(exp -9) ergs/sq cm/s/sr cm limited by a detector and cosmic-ray noise. The monopole temperature is consistent with that determined by direct measurement in the accompanying article by Mather et al.
Determining neutrino mass from the cosmic microwave background alone.
Kaplinghat, Manoj; Knox, Lloyd; Song, Yong-Seon
2003-12-12
Distortions of cosmic microwave background temperature and polarization maps caused by gravitational lensing, observable with high angular resolution and high sensitivity, can be used to measure the neutrino mass. Assuming two massless species and one with mass m(nu), we forecast sigma(m(nu))=0.15 eV from the Planck satellite and sigma(m(nu))=0.04 eV from observations with twice the angular resolution and approximately 20 times the sensitivity. A detection is likely at this higher sensitivity since the observation of atmospheric neutrino oscillations requires Deltam(2)(nu) greater, similar (0.04 eV)(2).
Dossett, Lesly A.; Fox, Erin E.; del Junco, Deborah J.; Zaydfudim, Victor; Kauffmann, Rondi; Shelton, Julia; Wang, Weiwei; Cioffi, William G.; Holcomb, John B.; Cotton, Bryan A.
2014-01-01
BACKGROUND As a primary venue for presenting research results, abstracts selected for presentation at national meetings should be of the highest scientific merit and research quality. It is uncertain to what degree this is achieved as the methodological quality of abstracts submitted to national surgical meetings has not been previously described. The objective of this study was to evaluate abstracts presented at a leading trauma meeting for methodological quality. METHODS All abstracts accepted for the 2009 American Association for the Surgery of Trauma meeting were reviewed and scored for methodological quality based on 10 criteria (scores, 0–10; 10 being the highest). Criteria were based on nationally published methodology guidelines. Two independent reviewers who were blinded to institution, region, and author reviewed each abstract. RESULTS A total of 187 abstracts were accepted for presentation (67 oral and 120 posters). The most frequent clinical topics were shock/transfusion (23%), abdomen (12%), and nervous system (11%). Shock/transfusion abstracts were more common in the oral presentations (31% vs. 19%; p =0.06). Abstracts from the northeast and south regions were the most common in both oral (26% and 29%) and posters (25% and 24%). Basic science accounted for 12% of accepted studies, while 51% were clinical and 28% were health services/outcomes. Only 8% of abstracts presented randomized data and only 11% reported null findings. Overall abstract scores ranged from 3 to 10 (median, 7; mean, 7.4). Abstracts selected for poster presentation had an overall higher score than those selected for oral presentation (7.4 ±1.7 vs. 6.8 ±1.7; p =0.02). CONCLUSION Although oral presentations traditionally receive the most attention and interest, the methodological quality of abstracts accepted for poster presentation equals (and sometimes exceeds) that of oral abstracts. Attendees of these national meetings should reconsider their time spent in viewing and visiting
The semantic richness of abstract concepts
Recchia, Gabriel; Jones, Michael N.
2012-01-01
We contrasted the predictive power of three measures of semantic richness—number of features (NFs), contextual dispersion (CD), and a novel measure of number of semantic neighbors (NSN)—for a large set of concrete and abstract concepts on lexical decision and naming tasks. NSN (but not NF) facilitated processing for abstract concepts, while NF (but not NSN) facilitated processing for the most concrete concepts, consistent with claims that linguistic information is more relevant for abstract concepts in early processing. Additionally, converging evidence from two datasets suggests that when NSN and CD are controlled for, the features that most facilitate processing are those associated with a concept's physical characteristics and real-world contexts. These results suggest that rich linguistic contexts (many semantic neighbors) facilitate early activation of abstract concepts, whereas concrete concepts benefit more from rich physical contexts (many associated objects and locations). PMID:23205008
More on approximations of Poisson probabilities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kao, C
1980-05-01
Calculation of Poisson probabilities frequently involves calculating high factorials, which becomes tedious and time-consuming with regular calculators. The usual way to overcome this difficulty has been to find approximations by making use of the table of the standard normal distribution. A new transformation proposed by Kao in 1978 appears to perform better for this purpose than traditional transformations. In the present paper several approximation methods are stated and compared numerically, including an approximation method that utilizes a modified version of Kao's transformation. An approximation based on a power transformation was found to outperform those based on the square-root type transformationsmore » as proposed in literature. The traditional Wilson-Hilferty approximation and Makabe-Morimura approximation are extremely poor compared with this approximation. 4 tables. (RWR)« less
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.
Tan, Ting; Yang, Xueliang; Krauter, Caroline M; Ju, Yiguang; Carter, Emily A
2015-06-18
The kinetics of hydrogen abstraction by five radicals (H, O((3)P), OH, CH3, and HO2) from methyl acetate (MA) is investigated theoretically in order to gain further understanding of certain aspects of the combustion chemistry of biodiesels, such as the effect of the ester moiety. We employ ab initio quantum chemistry methods, coupled cluster singles and doubles with perturbative triples correction (CCSD(T)) and multireference averaged coupled pair functional theory (MRACPF2), to predict chemically accurate reaction energetics. Overall, MRACPF2 predicts slightly higher barrier heights than CCSD(T) for MA + H/CH3/O/OH, but slightly lower barrier heights for hydrogen abstraction by HO2. Based on the obtained reaction energies, we also report high-pressure-limit rate constants using transition state theory (TST) in conjunction with the separable-hindered-rotor approximation, the variable reaction coordinate TST, and the multi-structure all-structure approach. The fitted modified Arrhenius expressions are provided over a temperature range of 250 to 2000 K. The predictions are in good agreement with available experimental results. Abstractions from both of the methyl groups in MA are expected to contribute to consumption of the fuel as they exhibit similar rate coefficients. The reactions involving the OH radical are predicted to have the highest rates among the five abstracting radicals, while those initiated by HO2 are expected to be the lowest.
Park, Subok; Gallas, Bradon D; Badano, Aldo; Petrick, Nicholas A; Myers, Kyle J
2007-04-01
A previous study [J. Opt. Soc. Am. A22, 3 (2005)] has shown that human efficiency for detecting a Gaussian signal at a known location in non-Gaussian distributed lumpy backgrounds is approximately 4%. This human efficiency is much less than the reported 40% efficiency that has been documented for Gaussian-distributed lumpy backgrounds [J. Opt. Soc. Am. A16, 694 (1999) and J. Opt. Soc. Am. A18, 473 (2001)]. We conducted a psychophysical study with a number of changes, specifically in display-device calibration and data scaling, from the design of the aforementioned study. Human efficiency relative to the ideal observer was found again to be approximately 5%. Our variance analysis indicates that neither scaling nor display made a statistically significant difference in human performance for the task. We conclude that the non-Gaussian distributed lumpy background is a major factor in our low human-efficiency results.
NASA Technical Reports Server (NTRS)
Mule, Peter; Hill, Michael D.; Sampler, Henry P.
2000-01-01
The Microwave Anisotropy Probe (MAP) Observatory, scheduled for a fall 2000 launch, is designed to measure temperature fluctuations (anisotropy) and produce a high sensitivity and high spatial resolution (better than 0.3 deg.) map of the cosmic microwave background (CMB) radiation over the entire sky between 22 and 90 GHz. MAP utilizes back-to-back composite Gregorian telescopes supported on a composite truss structure to focus the microwave signals into 10 differential microwave receivers. Proper position and shape of the telescope reflectors at the operating temperature of approximately 90 K is a critical element to ensuring mission success. We describe the methods and analysis used to validate the in-flight position and shape predictions for the reflectors based on photogrammetric (PG) metrology data taken under vacuum with the reflectors at approximately 90 K. Contour maps showing reflector distortion analytical extrapolations were generated. The resulting reflector distortion data are shown to be crucial to the analytical assessment of the MAP instrument's microwave system in-flight performance.
Abstractive dissociation of oxygen over Al(111): a nonadiabatic quantum model.
Katz, Gil; Kosloff, Ronnie; Zeiri, Yehuda
2004-02-22
The dissociation of oxygen on a clean aluminum surface is studied theoretically. A nonadiabatic quantum dynamical model is used, based on four electronically distinct potential energy surfaces characterized by the extent of charge transfer from the metal to the adsorbate. A flat surface approximation is used to reduce the computation complexity. The conservation of the helicopter angular momentum allows Boltzmann averaging of the outcome of the propagation of a three degrees of freedom wave function. The dissociation event is simulated by solving the time-dependent Schrödinger equation for a period of 30 femtoseconds. As a function of incident kinetic energy, the dissociation yield follows the experimental trend. An attempt at simulation employing only the lowest adiabatic surface failed, qualitatively disagreeing with both experiment and nonadiabatic calculations. The final products, adsorptive dissociation and abstractive dissociation, are obtained by carrying out a semiclassical molecular dynamics simulation with surface hopping which describes the back charge transfer from an oxygen atom negative ion to the surface. The final adsorbed oxygen pair distribution compares well with experiment. By running the dynamical events backward in time, a correlation is established between the products and the initial conditions which lead to their production. Qualitative agreement is thus obtained with recent experiments that show suppression of abstraction by rotational excitation. (c) 2004 American Institute of Physics.
Olfactory language and abstraction across cultures
Burenhult, Niclas; Stensmyr, Marcus; de Valk, Josje; Hansson, Bill S.
2018-01-01
Olfaction presents a particularly interesting arena to explore abstraction in language. Like other abstract domains, such as time, odours can be difficult to conceptualize. An odour cannot be seen or held, it can be difficult to locate in space, and for most people odours are difficult to verbalize. On the other hand, odours give rise to primary sensory experiences. Every time we inhale we are using olfaction to make sense of our environment. We present new experimental data from 30 Jahai hunter-gatherers from the Malay Peninsula and 30 matched Dutch participants from the Netherlands in an odour naming experiment. Participants smelled monomolecular odorants and named odours while reaction times, odour descriptors and facial expressions were measured. We show that while Dutch speakers relied on concrete descriptors, i.e. they referred to odour sources (e.g. smells like lemon), the Jahai used abstract vocabulary to name the same odours (e.g. musty). Despite this differential linguistic categorization, analysis of facial expressions showed that the two groups, nevertheless, had the same initial emotional reactions to odours. Critically, these cross-cultural data present a challenge for how to think about abstraction in language. This article is part of the theme issue ‘Varieties of abstract concepts: development, use and representation in the brain’. PMID:29915007
Approximate circuits for increased reliability
DOE Office of Scientific and Technical Information (OSTI.GOV)
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 referencemore » 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.« less
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…
ERIC Educational Resources Information Center
Wilson, Cynthia, Ed.
2001-01-01
This is volume 14 of Leadership Abstracts, a newsletter published by the League for Innovation (California). Issue 1 of February 2001, "Developmental Education: A Policy Primer," discusses developmental programs in the community college. According to the article, community college trustees and presidents would serve their constituents well by…
A novel background field removal method for MRI using projection onto dipole fields (PDF).
Liu, Tian; Khalidov, Ildar; de Rochefort, Ludovic; Spincemaille, Pascal; Liu, Jing; Tsiouris, A John; Wang, Yi
2011-11-01
For optimal image quality in susceptibility-weighted imaging and accurate quantification of susceptibility, it is necessary to isolate the local field generated by local magnetic sources (such as iron) from the background field that arises from imperfect shimming and variations in magnetic susceptibility of surrounding tissues (including air). Previous background removal techniques have limited effectiveness depending on the accuracy of model assumptions or information input. In this article, we report an observation that the magnetic field for a dipole outside a given region of interest (ROI) is approximately orthogonal to the magnetic field of a dipole inside the ROI. Accordingly, we propose a nonparametric background field removal technique based on projection onto dipole fields (PDF). In this PDF technique, the background field inside an ROI is decomposed into a field originating from dipoles outside the ROI using the projection theorem in Hilbert space. This novel PDF background removal technique was validated on a numerical simulation and a phantom experiment and was applied in human brain imaging, demonstrating substantial improvement in background field removal compared with the commonly used high-pass filtering method. Copyright © 2011 John Wiley & Sons, Ltd.
Poyer, R K
1984-01-01
Journal article overlap is defined as the same journal article being indexed by two or more services. Using journal references from seventy dissertations written in the preclinical sciences, the extent of journal article overlap among Index Medicus, Science Citation Index, Biological Abstracts, and Chemical Abstracts was examined. Of the 7,969 journal references cited, 92% were indexed by at least two of these services; 591 articles were covered by only one of the services, and 55 articles were not indexed. A discussion of the advantages and costs of journal article overlap is presented. PMID:6388693
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;…
Mathematical Abstraction: Constructing Concept of Parallel Coordinates
NASA Astrophysics Data System (ADS)
Nurhasanah, F.; Kusumah, Y. S.; Sabandar, J.; Suryadi, D.
2017-09-01
Mathematical abstraction is an important process in teaching and learning mathematics so pre-service mathematics teachers need to understand and experience this process. One of the theoretical-methodological frameworks for studying this process is Abstraction in Context (AiC). Based on this framework, abstraction process comprises of observable epistemic actions, Recognition, Building-With, Construction, and Consolidation called as RBC + C model. This study investigates and analyzes how pre-service mathematics teachers constructed and consolidated concept of Parallel Coordinates in a group discussion. It uses AiC framework for analyzing mathematical abstraction of a group of pre-service teachers consisted of four students in learning Parallel Coordinates concepts. The data were collected through video recording, students’ worksheet, test, and field notes. The result shows that the students’ prior knowledge related to concept of the Cartesian coordinate has significant role in the process of constructing Parallel Coordinates concept as a new knowledge. The consolidation process is influenced by the social interaction between group members. The abstraction process taken place in this group were dominated by empirical abstraction that emphasizes on the aspect of identifying characteristic of manipulated or imagined object during the process of recognizing and building-with.
Ghimire, Saurav; Kyung, Eunjung; Lee, Heeyoung; Kim, Eunyoung
2014-06-01
The aims of this study were to evaluate the quality of randomized controlled trial (RCT) abstracts published in the field of oncology and identify characteristics associated with better reporting quality. All phase III trials published during 2005-2007 [before Consolidated Standards of Reporting Trials (CONSORT)] and 2010-2012 (after CONSORT) were searched electronically in MEDLINE/PubMed and retrieved for review using an 18-point overall quality score (OQS) for reporting based on the CONSORT for Abstract guidelines. Descriptive statistics followed by multivariate linear regression were used to identify features associated with improved reporting quality. The mean OQS was 8.2 (range: 5-13; 95% confidence interval (CI): 8.0, 8.3) and 9.9 (range: 5-18; 95% CI: 9.7, 10.2) in the pre- and post-CONSORT periods, respectively. The method for random sequence generation, allocation concealment, blinding details, and funding sources were missing in pre-CONSORT abstracts and insufficiently reported (<20%) in post-CONSORT abstracts. A high impact factor (P < 0.001) and the journal of publication (P < 0.001) were independent factors that were significantly associated with higher reporting quality on multivariate analysis. The reporting quality of RCT abstracts in oncology showed suboptimal improvement over time. Thus, stricter adherence to the CONSORT for Abstract guidelines is needed to improve the reporting quality of RCT abstracts published in oncology. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Harrison, F. A.; Aird, J.; Civano, F.; Lansbury, G.; Mullaney, J. R.; Ballentyne, D. R.; Alexander, D. M.; Stern, D.; Ajello, M.; Barret, D.;
2016-01-01
We present the 3-8 kiloelectronvolts and 8-24 kiloelectronvolts number counts of active galactic nuclei (AGNs) identified in the Nuclear Spectroscopic Telescope Array (NuSTAR) extragalactic surveys. NuSTAR has now resolved 33 percent -39 percent of the X-ray background in the 8-24 kiloelectronvolts band, directly identifying AGNs with obscuring columns up to approximately 10 (exp 25) per square centimeter. In the softer 3-8 kiloelectronvolts band the number counts are in general agreement with those measured by XMM-Newton and Chandra over the flux range 5 times 10 (exp -15) less than or approximately equal to S (3-8 kiloelectronvolts) divided by ergs per second per square centimeter less than or approximately equal to 10 (exp -12) probed by NuSTAR. In the hard 8-24 kiloelectronvolts band NuSTAR probes fluxes over the range 2 times 10 (exp -14) less than or approximately equal to S (8-24 kiloelectronvolts) divided by ergs per second per square centimeter less than or approximately equal to 10 (exp -12), a factor approximately 100 times fainter than previous measurements. The 8-24 kiloelectronvolts number counts match predictions from AGN population synthesis models, directly confirming the existence of a population of obscured and/or hard X-ray sources inferred from the shape of the integrated cosmic X-ray background. The measured NuSTAR counts lie significantly above simple extrapolation with a Euclidian slope to low flux of the Swift/BAT15-55 kiloelectronvolts number counts measured at higher fluxes (S (15-55 kiloelectronvolts) less than or approximately equal to 10 (exp -11) ergs per second per square centimeter), reflecting the evolution of the AGN population between the Swift/BAT local (redshift is less than 0.1) sample and NuSTAR's redshift approximately equal to 1 sample. CXB (Cosmic X-ray Background) synthesis models, which account for AGN evolution, lie above the Swift/BAT measurements, suggesting that they do not fully capture the evolution of obscured
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…
Mueller, Silke M; Schiebener, Johannes; Delazer, Margarete; Brand, Matthias
2018-01-22
Many decision situations in everyday life involve mathematical considerations. In decisions under objective risk, i.e., when explicit numeric information is available, executive functions and abilities to handle exact numbers and ratios are predictors of objectively advantageous choices. Although still debated, exact numeric abilities, e.g., normative calculation skills, are assumed to be related to approximate number processing skills. The current study investigates the effects of approximative numeric abilities on decision making under objective risk. Participants (N = 153) performed a paradigm measuring number-comparison, quantity-estimation, risk-estimation, and decision-making skills on the basis of rapid dot comparisons. Additionally, a risky decision-making task with exact numeric information was administered, as well as tasks measuring executive functions and exact numeric abilities, e.g., mental calculation and ratio processing skills, were conducted. Approximative numeric abilities significantly predicted advantageous decision making, even beyond the effects of executive functions and exact numeric skills. Especially being able to make accurate risk estimations seemed to contribute to superior choices. We recommend approximation skills and approximate number processing to be subject of future investigations on decision making under risk.
Abstraction in Mathematics and Mathematics Learning
ERIC Educational Resources Information Center
Mitchelmore, Michael; White, Paul
2004-01-01
It is claimed that, since mathematics is essentially a self-contained system, mathematical objects may best be described as "abstract-apart." On the other hand, fundamental mathematical ideas are closely related to the real world and their learning involves empirical concepts. These concepts may be called "abstract-general" because they embody…
Dissertation Abstracts in Mathematics Education, 1983.
ERIC Educational Resources Information Center
Suydam, Marilyn N., Comp.
The dissertation abstracts in this compilation all appeared in "Dissertation Abstracts International" in 1983. The 300 dissertations cited in the annual listing of research in the July 1984 issue of the "Journal for Research in Mathematics Education" are included, as well as 55 dissertations which were located but could not be…
The 2nd United Kingdom Extracellular Vesicle Forum Meeting Abstracts
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
The Nature of the Unresolved Extragalactic Cosmic Soft X-Ray Background
NASA Technical Reports Server (NTRS)
Cappelluti, N.; Ranalli, P.; Roncarelli, M.; Arevalo, P.; Zamorani, G.; Comastri, A.; Gilli, R.; Rovilos, E.; Vignali, C.; Allevato, V.;
2013-01-01
In this paper we investigate the power spectrum of the unresolved 0.5-2 keV cosmic X-ray background (CXB) with deep Chandra 4-Msec (Ms) observations in the Chandra Deep Field South (CDFS). We measured a signal that, on scales >30 arcsec, is significantly higher than the shot noise and is increasing with angular scale. We interpreted this signal as the joint contribution of clustered undetected sources like active galactic nuclei (AGN), galaxies and the intergalactic medium (IGM). The power of unresolved cosmic source fluctuations accounts for approximately 12 per cent of the 0.5-2 keV extragalactic CXB. Overall, our modelling predicts that approximately 20 per cent of the unresolved CXB flux is produced by low-luminosity AGN, approximately 25 per cent by galaxies and approximately 55 per cent by the IGM. We do not find any direct evidence of the so-called 'warm hot intergalactic medium' (i.e. matter with 10(exp 5) less than T less than 10(exp 7) K and density contrast delta less than 1000), but we estimated that it could produce about 1/7 of the unresolved CXB. We placed an upper limit on the space density of postulated X-ray-emitting early black holes at z greater than 7.5 and compared it with supermassive black hole evolution models.
Automated Assume-Guarantee Reasoning by Abstraction Refinement
NASA Technical Reports Server (NTRS)
Pasareanu, Corina S.; Giannakopoulous, Dimitra; Glannakopoulou, Dimitra
2008-01-01
Current automated approaches for compositional model checking in the assume-guarantee style are based on learning of assumptions as deterministic automata. We propose an alternative approach based on abstraction refinement. Our new method computes the assumptions for the assume-guarantee rules as conservative and not necessarily deterministic abstractions of some of the components, and refines those abstractions using counter-examples obtained from model checking them together with the other components. Our approach also exploits the alphabets of the interfaces between components and performs iterative refinement of those alphabets as well as of the abstractions. We show experimentally that our preliminary implementation of the proposed alternative achieves similar or better performance than a previous learning-based implementation.
Correlation between low level fluctuations in the x ray background and faint galaxies
NASA Technical Reports Server (NTRS)
Tolstoy, Eline; Griffiths, R. E.
1993-01-01
A correlation between low-level x-ray fluctuations in the cosmic x-ray background flux and the large numbers of galaxies found in deep optical imaging, to m(sub v) is less than or equal to 24 - 26, is desired. These (faint) galaxies by their morphology and color in deep multi-color CCD images and plate material were optically identified. Statistically significant correlations between these galaxies and low-level x-ray fluctuations at the same positions in multiple deep Einstein HRI observations in PAVO and in a ROSAT PSPC field were searched for. Our aim is to test the hypothesis that faint 'star burst' galaxies might contribute significantly to the cosmic x-ray background (at approximately 1 keV).
The representation of abstract words: why emotion matters.
Kousta, Stavroula-Thaleia; Vigliocco, Gabriella; Vinson, David P; Andrews, Mark; Del Campo, Elena
2011-02-01
Although much is known about the representation and processing of concrete concepts, knowledge of what abstract semantics might be is severely limited. In this article we first address the adequacy of the 2 dominant accounts (dual coding theory and the context availability model) put forward in order to explain representation and processing differences between concrete and abstract words. We find that neither proposal can account for experimental findings and that this is, at least partly, because abstract words are considered to be unrelated to experiential information in both of these accounts. We then address a particular type of experiential information, emotional content, and demonstrate that it plays a crucial role in the processing and representation of abstract concepts: Statistically, abstract words are more emotionally valenced than are concrete words, and this accounts for a residual latency advantage for abstract words, when variables such as imageability (a construct derived from dual coding theory) and rated context availability are held constant. We conclude with a discussion of our novel hypothesis for embodied abstract semantics. (c) 2010 APA, all rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wong, Jerry T.; Kamyar, Farzad; Molloi, Sabee
2007-10-15
Densitometry measurements have been performed previously using subtracted images. However, digital subtraction angiography (DSA) in coronary angiography is highly susceptible to misregistration artifacts due to the temporal separation of background and target images. Misregistration artifacts due to respiration and patient motion occur frequently, and organ motion is unavoidable. Quantitative densitometric techniques would be more clinically feasible if they could be implemented using unsubtracted images. The goal of this study is to evaluate image recovery techniques for densitometry measurements using unsubtracted images. A humanoid phantom and eight swine (25-35 kg) were used to evaluate the accuracy and precision of the followingmore » image recovery techniques: Local averaging (LA), morphological filtering (MF), linear interpolation (LI), and curvature-driven diffusion image inpainting (CDD). Images of iodinated vessel phantoms placed over the heart of the humanoid phantom or swine were acquired. In addition, coronary angiograms were obtained after power injections of a nonionic iodinated contrast solution in an in vivo swine study. Background signals were estimated and removed with LA, MF, LI, and CDD. Iodine masses in the vessel phantoms were quantified and compared to known amounts. Moreover, the total iodine in left anterior descending arteries was measured and compared with DSA measurements. In the humanoid phantom study, the average root mean square errors associated with quantifying iodine mass using LA and MF were approximately 6% and 9%, respectively. The corresponding average root mean square errors associated with quantifying iodine mass using LI and CDD were both approximately 3%. In the in vivo swine study, the root mean square errors associated with quantifying iodine in the vessel phantoms with LA and MF were approximately 5% and 12%, respectively. The corresponding average root mean square errors using LI and CDD were both 3%. The standard
High-Level Data-Abstraction System
NASA Technical Reports Server (NTRS)
Fishwick, P. A.
1986-01-01
Communication with data-base processor flexible and efficient. High Level Data Abstraction (HILDA) system is three-layer system supporting data-abstraction features of Intel data-base processor (DBP). Purpose of HILDA establishment of flexible method of efficiently communicating with DBP. Power of HILDA lies in its extensibility with regard to syntax and semantic changes. HILDA's high-level query language readily modified. Offers powerful potential to computer sites where DBP attached to DEC VAX-series computer. HILDA system written in Pascal and FORTRAN 77 for interactive execution.
2010-01-01
Background An increase in work on the full text of journal articles and the growth of PubMedCentral have the opportunity to create a major paradigm shift in how biomedical text mining is done. However, until now there has been no comprehensive characterization of how the bodies of full text journal articles differ from the abstracts that until now have been the subject of most biomedical text mining research. Results We examined the structural and linguistic aspects of abstracts and bodies of full text articles, the performance of text mining tools on both, and the distribution of a variety of semantic classes of named entities between them. We found marked structural differences, with longer sentences in the article bodies and much heavier use of parenthesized material in the bodies than in the abstracts. We found content differences with respect to linguistic features. Three out of four of the linguistic features that we examined were statistically significantly differently distributed between the two genres. We also found content differences with respect to the distribution of semantic features. There were significantly different densities per thousand words for three out of four semantic classes, and clear differences in the extent to which they appeared in the two genres. With respect to the performance of text mining tools, we found that a mutation finder performed equally well in both genres, but that a wide variety of gene mention systems performed much worse on article bodies than they did on abstracts. POS tagging was also more accurate in abstracts than in article bodies. Conclusions Aspects of structure and content differ markedly between article abstracts and article bodies. A number of these differences may pose problems as the text mining field moves more into the area of processing full-text articles. However, these differences also present a number of opportunities for the extraction of data types, particularly that found in parenthesized text
Combining global and local approximations
NASA Technical Reports Server (NTRS)
Haftka, Raphael T.
1991-01-01
A method based on a linear approximation to a scaling factor, designated the 'global-local approximation' (GLA) method, is presented and shown capable of extending the range of usefulness of derivative-based approximations to a more refined model. The GLA approach refines the conventional scaling factor by means of a linearly varying, rather than constant, scaling factor. The capabilities of the method are demonstrated for a simple beam example with a crude and more refined FEM model.
Prendergast, Sarah; Mattishent, Katharina; Broughton, Tom; Beales, Ian
2013-01-01
Background: Reports have suggested that academic medicine may be in decline within the UK. Further evidence suggests that rates of subsequent full publication of abstracts presented at major scientific meetings are low and may be declining. We have compared the publication rates of abstracts presented at meetings of the British Society of Gastroenterology (BSG) between 1995 and 2005 and examined factors associated with full paper publication. Methods: Abstracts presented at BSG meetings in 1995 and 2005 were assessed by cross-referencing with multiple databases. Abstract characteristics associated with publication were analysed. Results: There were no differences in overall publication rates, impact factors or time to publication between 1995 and 2005. Overall, basic-science abstracts were twice as likely to achieve full publication than non-basic science. There was a significant fall in the publication rates for case series and audits, and significantly increased rates for fundamental/basic-science abstracts over the study period. There were non-significant increases in publication rates for controlled trials and systematic reviews. In general, publication rates for all predominantly clinically orientated abstracts reduced between the two periods with the most notable fall occurring in nutrition. Conclusions: There was no evidence of a decline in overall abstract publication rates between 1995 and 2005. There seemed to be trend for increased publication rates of abstracts using perceived high-quality study methodologies with a corresponding decrease in those with lower quality methods. The proportion of basic-science abstracts is likely to be a determinant of overall full publication rates following scientific meetings.
Conference Abstracts: AEDS '82.
ERIC Educational Resources Information Center
Journal of Computers in Mathematics and Science Teaching, 1982
1982-01-01
Abstracts from nine selected papers presented at the 1982 Association for Educational Data Systems (AEDS) conference are provided. Copies of conference proceedings may be obtained for fifteen dollars from the Association. (MP)
Spline approximation, Part 1: Basic methodology
NASA Astrophysics Data System (ADS)
Ezhov, Nikolaj; Neitzel, Frank; Petrovic, Svetozar
2018-04-01
In engineering geodesy point clouds derived from terrestrial laser scanning or from photogrammetric approaches are almost never used as final results. For further processing and analysis a curve or surface approximation with a continuous mathematical function is required. In this paper the approximation of 2D curves by means of splines is treated. Splines offer quite flexible and elegant solutions for interpolation or approximation of "irregularly" distributed data. Depending on the problem they can be expressed as a function or as a set of equations that depend on some parameter. Many different types of splines can be used for spline approximation and all of them have certain advantages and disadvantages depending on the approximation problem. In a series of three articles spline approximation is presented from a geodetic point of view. In this paper (Part 1) the basic methodology of spline approximation is demonstrated using splines constructed from ordinary polynomials and splines constructed from truncated polynomials. In the forthcoming Part 2 the notion of B-spline will be explained in a unique way, namely by using the concept of convex combinations. The numerical stability of all spline approximation approaches as well as the utilization of splines for deformation detection will be investigated on numerical examples in Part 3.
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.
User-Extensible Graphics Using Abstract Structure,
1987-08-01
Flex 6 The Algol68 model of the graphical abstract structure 5 The creation of a PictureDefinition 6 The making of a picture from a PictureDefinition 7...data together with the operations that can be performed on that data. i 7! ś I _ § 4, The Alqol68 model of the graphical abstract structure Every
Characteristic microwave background distortions from collapsing domain wall bubbles
NASA Technical Reports Server (NTRS)
Goetz, Guenter; Noetzold, Dirk
1990-01-01
The magnitude and angular pattern of distortions of the microwave background are analyzed by collapsing spherical domain walls. A characteristic pattern of redshift distortions of red or blue spikes surrounded by blue discs was found. The width and height of a spike is related to the diameter and magnitude of the disc. A measurement of the relations between these quantities thus can serve as an unambiguous indicator for a collapsing spherical domain wall. From the redshift distortion in the blue discs an upper bound was found on the surface energy density of the walls sigma is less than or approximately 8 MeV cubed.
The faint galaxy contribution to the diffuse extragalactic background light
NASA Technical Reports Server (NTRS)
Cole, Shaun; Treyer, Marie-Agnes; Silk, Joseph
1992-01-01
Models of the faint galaxy contribution to the diffuse extragalactic background light are presented, which are consistent with current data on faint galaxy number counts and redshifts. The autocorrelation function of surface brightness fluctuations in the extragalactic diffuse light is predicted, and the way in which these predictions depend on the cosmological model and assumptions of biasing is determined. It is confirmed that the recent deep infrared number counts are most compatible with a high density universe (Omega-0 is approximately equal to 1) and that the steep blue counts then require an extra population of rapidly evolving blue galaxies. The faintest presently detectable galaxies produce an interesting contribution to the extragalactic diffuse light, and still fainter galaxies may also produce a significant contribution. These faint galaxies still only produce a small fraction of the total optical diffuse background light, but on scales of a few arcminutes to a few degrees, they produce a substantial fraction of the fluctuations in the diffuse light.
Static Analysis Using Abstract Interpretation
NASA Technical Reports Server (NTRS)
Arthaud, Maxime
2017-01-01
Short presentation about static analysis and most particularly abstract interpretation. It starts with a brief explanation on why static analysis is used at NASA. Then, it describes the IKOS (Inference Kernel for Open Static Analyzers) tool chain. Results on NASA projects are shown. Several well known algorithms from the static analysis literature are then explained (such as pointer analyses, memory analyses, weak relational abstract domains, function summarization, etc.). It ends with interesting problems we encountered (such as C++ analysis with exception handling, or the detection of integer overflow).
Abstraction networks for terminologies: Supporting management of "big knowledge".
Halper, Michael; Gu, Huanying; Perl, Yehoshua; Ochs, Christopher
2015-05-01
Terminologies and terminological systems have assumed important roles in many medical information processing environments, giving rise to the "big knowledge" challenge when terminological content comprises tens of thousands to millions of concepts arranged in a tangled web of relationships. Use and maintenance of knowledge structures on that scale can be daunting. The notion of abstraction network is presented as a means of facilitating the usability, comprehensibility, visualization, and quality assurance of terminologies. An abstraction network overlays a terminology's underlying network structure at a higher level of abstraction. In particular, it provides a more compact view of the terminology's content, avoiding the display of minutiae. General abstraction network characteristics are discussed. Moreover, the notion of meta-abstraction network, existing at an even higher level of abstraction than a typical abstraction network, is described for cases where even the abstraction network itself represents a case of "big knowledge." Various features in the design of abstraction networks are demonstrated in a methodological survey of some existing abstraction networks previously developed and deployed for a variety of terminologies. The applicability of the general abstraction-network framework is shown through use-cases of various terminologies, including the Systematized Nomenclature of Medicine - Clinical Terms (SNOMED CT), the Medical Entities Dictionary (MED), and the Unified Medical Language System (UMLS). Important characteristics of the surveyed abstraction networks are provided, e.g., the magnitude of the respective size reduction referred to as the abstraction ratio. Specific benefits of these alternative terminology-network views, particularly their use in terminology quality assurance, are discussed. Examples of meta-abstraction networks are presented. The "big knowledge" challenge constitutes the use and maintenance of terminological structures that
Monotone Boolean approximation
DOE Office of Scientific and Technical Information (OSTI.GOV)
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 formore » the analysis of noncoherent fault trees and event tree sequences.« less
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.
Testing approximations for non-linear gravitational clustering
NASA Technical Reports Server (NTRS)
Coles, Peter; Melott, Adrian L.; Shandarin, Sergei F.
1993-01-01
The accuracy of various analytic approximations for following the evolution of cosmological density fluctuations into the nonlinear regime is investigated. The Zel'dovich approximation is found to be consistently the best approximation scheme. It is extremely accurate for power spectra characterized by n = -1 or less; when the approximation is 'enhanced' by truncating highly nonlinear Fourier modes the approximation is excellent even for n = +1. The performance of linear theory is less spectrum-dependent, but this approximation is less accurate than the Zel'dovich one for all cases because of the failure to treat dynamics. The lognormal approximation generally provides a very poor fit to the spatial pattern.
Towards ab initio Calculations with the Dynamical Vertex Approximation
NASA Astrophysics Data System (ADS)
Galler, Anna; Kaufmann, Josef; Gunacker, Patrik; Pickem, Matthias; Thunström, Patrik; Tomczak, Jan M.; Held, Karsten
2018-04-01
While key effects of the many-body problem — such as Kondo and Mott physics — can be understood in terms of on-site correlations, non-local fluctuations of charge, spin, and pairing amplitudes are at the heart of the most fascinating and unresolved phenomena in condensed matter physics. Here, we review recent progress in diagrammatic extensions to dynamical mean-field theory for ab initio materials calculations. We first recapitulate the quantum field theoretical background behind the two-particle vertex. Next we discuss latest algorithmic advances in quantum Monte Carlo simulations for calculating such two-particle quantities using worm sampling and vertex asymptotics, before giving an introduction to the ab initio dynamical vertex approximation (AbinitioDΓA). Finally, we highlight the potential of AbinitioDΓA by detailing results for the prototypical correlated metal SrVO3.
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…
[Quantitative Analysis of Heavy Metals in Water with LIBS Based on Signal-to-Background Ratio].
Hu, Li; Zhao, Nan-jing; Liu, Wen-qing; Fang, Li; Zhang, Da-hai; Wang, Yin; Meng, De Shuo; Yu, Yang; Ma, Ming-jun
2015-07-01
There are many influence factors in the precision and accuracy of the quantitative analysis with LIBS technology. According to approximately the same characteristics trend of background spectrum and characteristic spectrum along with the change of temperature through in-depth analysis, signal-to-background ratio (S/B) measurement and regression analysis could compensate the spectral line intensity changes caused by system parameters such as laser power, spectral efficiency of receiving. Because the measurement dates were limited and nonlinear, we used support vector machine (SVM) for regression algorithm. The experimental results showed that the method could improve the stability and the accuracy of quantitative analysis of LIBS, and the relative standard deviation and average relative error of test set respectively were 4.7% and 9.5%. Data fitting method based on signal-to-background ratio(S/B) is Less susceptible to matrix elements and background spectrum etc, and provides data processing reference for real-time online LIBS quantitative analysis technology.
Alvarez, Sergio A; Winner, Ellen; Hawley-Dolan, Angelina; Snapper, Leslie
2015-01-01
People with no arts background often misunderstand abstract art as requiring no skill. However, adults with no art background discriminate paintings by abstract expressionists from superficially similar works by children and animals. We tested whether participants show different visual exploration when looking at paintings by artists' versus children or animals. Participants sat at an eye tracker and viewed paintings by artists paired with "similar" paintings by children or animals, and were asked which they preferred and which was better. Mean duration of eye gaze fixations, total fixation time, and spatial extent of visual exploration was greater to the artist than child or animal images in response to quality but not preference. Pupil dilation was greater to the artist images in response to both questions and greater in response to the quality than preference question. Explicit selections of images paralleled total fixation times: Participants selected at chance for preference, but selected the artist images above chance in response to quality. Results show that lay adults respond differently on both an implicit as well as explicit measure when thinking about preference versus quality in art and discriminate abstract paintings by artists from superficially similar works by children and animals, despite the popular misconception by the average viewer that "my kid could have done that." © The Author(s) 2015.
Primativo, Silvia; Reilly, Jamie; Crutch, Sebastian J
2016-01-01
The Abstract Conceptual Feature (ACF) framework predicts that word meaning is represented within a high-dimensional semantic space bounded by weighted contributions of perceptual, affective, and encyclopedic information. The ACF, like latent semantic analysis, is amenable to distance metrics between any two words. We applied predictions of the ACF framework to abstract words using eye tracking via an adaptation of the classical ‘visual word paradigm’. Healthy adults (N=20) selected the lexical item most related to a probe word in a 4-item written word array comprising the target and three distractors. The relation between the probe and each of the four words was determined using the semantic distance metrics derived from ACF ratings. Eye-movement data indicated that the word that was most semantically related to the probe received more and longer fixations relative to distractors. Importantly, in sets where participants did not provide an overt behavioral response, the fixation rates were none the less significantly higher for targets than distractors, closely resembling trials where an expected response was given. Furthermore, ACF ratings which are based on individual words predicted eye fixation metrics of probe-target similarity at least as well as latent semantic analysis ratings which are based on word co-occurrence. The results provide further validation of Euclidean distance metrics derived from ACF ratings as a measure of one facet of the semantic relatedness of abstract words and suggest that they represent a reasonable approximation of the organization of abstract conceptual space. The data are also compatible with the broad notion that multiple sources of information (not restricted to sensorimotor and emotion information) shape the organization of abstract concepts. Whilst the adapted ‘visual word paradigm’ is potentially a more metacognitive task than the classical visual world paradigm, we argue that it offers potential utility for studying
Faint blue counts from formation of dwarf galaxies at z approximately equals 1
NASA Technical Reports Server (NTRS)
Babul, Arif; Rees, Martin J.
1993-01-01
The nature of faint blue objects (FBO's) has been a source of much speculation since their detection in deep CCD images of the sky. Their high surface density argues against them being progenitors of present-day bright galaxies and since they are only weakly clustered on small scales, they cannot be entities that merged together to form present-day galaxies. Babul & Rees (1992) have suggested that the observed faint blue counts may be due to dwarf elliptical galaxies undergoing their initial starburst at z is approximately equal to 1. In generic hierarchical clustering scenarios, however, dwarf galaxy halos (M is approximately 10(exp 9) solar mass) are expected to form at an earlier epoch; for example, typical 10(exp 9) solar mass halos will virialize at z is approximately equal to 2.3 if the power-spectrum for the density fluctuations is that of the standard b = 2 cold dark matter (CDM) model. Under 'ordinary conditions' the gas would rapidly cool, collect in the cores, and undergo star-formation. Conditions at high redshifts are far from 'ordinary'. The intense UV background will prevent the gas in the dwarf halos from cooling, the halos being released from their suspended state only when the UV flux has diminished sufficiently.
Selected abstracts on aviation weather hazard research
DOT National Transportation Integrated Search
1996-01-01
This paper consists of bibliographic information and abstracts for literature on the topics of weather-related aviation hazards. These abstracts were selected from reports written for the ASR-9, ITWS, TDWR programs, sponsored by the Federal Aviation ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mace, Emily K.; Aalseth, Craig E.; Bonicalzi, Ricco
Abstract. Characterization of two sets of custom unequal length proportional counters is underway at Pacific Northwest National Laboratory (PNNL). These detectors will be used in measurements to determine the absolute activity concentration of gaseous radionuclides (e.g., 37Ar). A set of three detectors has been fabricated based on previous PNNL ultra-low-background proportional counters (ULBPC) designs and now operate in PNNL’s shallow underground counting laboratory. A second set of four counters has also been fabricated using clean assembly of OFHC copper components for use in an above-ground counting laboratory. Characterization of both sets of detectors is underway with measurements of background rates,more » gas gain, energy resolution, and shielding considerations. These results will be presented along with uncertainty estimates of future absolute gas counting measurements.« less
NASA Astrophysics Data System (ADS)
Zhang, Dongbo; Peng, Yinghui; Yi, Yao; Shang, Xingyu
2013-10-01
Detection of red lesions [hemorrhages (HRs) and microaneurysms (MAs)] is crucial for the diagnosis of early diabetic retinopathy. A method based on background estimation and adapted to specific characteristics of HRs and MAs is proposed. Candidate red lesions are located by background estimation and Mahalanobis distance measure and then some adaptive postprocessing techniques, which include vessel detection, nonvessel exclusion based on shape analysis, and noise points exclusion by double-ring filter (only used for MAs detection), are conducted to remove nonlesion pixels. The method is evaluated on our collected image dataset, and experimental results show that it is better than or approximate to other previous approaches. It is effective to reduce the false-positive and false-negative results that arise from incomplete and inaccurate vessel structure.
On the Power of Abstract Interpretation
NASA Technical Reports Server (NTRS)
Reddy, Uday S.; Kamin, Samuel N.
1991-01-01
Increasingly sophisticated applications of static analysis place increased burden on the reliability of the analysis techniques. Often, the failure of the analysis technique to detect some information my mean that the time or space complexity of the generated code would be altered. Thus, it is important to precisely characterize the power of static analysis techniques. We follow the approach of Selur et. al. who studied the power of strictness analysis techniques. Their result can be summarized by saying 'strictness analysis is perfect up to variations in constants.' In other words, strictness analysis is as good as it could be, short of actually distinguishing between concrete values. We use this approach to characterize a broad class of analysis techniques based on abstract interpretation including, but not limited to, strictness analysis. For the first-order case, we consider abstract interpretations where the abstract domain for data values is totally ordered. This condition is satisfied by Mycroft's strictness analysis that of Sekar et. al. and Wadler's analysis of list-strictness. For such abstract interpretations, we show that the analysis is complete in the sense that, short of actually distinguishing between concrete values with the same abstraction, it gives the best possible information. We further generalize these results to typed lambda calculus with pairs and higher-order functions. Note that products and function spaces over totally ordered domains are not totally ordered. In fact, the notion of completeness used in the first-order case fails if product domains or function spaces are added. We formulate a weaker notion of completeness based on observability of values. Two values (including pairs and functions) are considered indistinguishable if their observable components are indistinguishable. We show that abstract interpretation of typed lambda calculus programs is complete up to this notion of indistinguishability. We use denotationally
Apparatus having reduced background for measuring radiation activity in aerosol particles
Rodgers, John C.; McFarland, Andrew R.; Oritz, Carlos A.; Marlow, William H.
1992-01-01
Apparatus having reduced background for measuring radiation activity in aerosol particles. A continuous air monitoring sampler is described for use in detecting the presence of alpha-emitting aerosol particles. An inlet fractionating screen has been demonstrated to remove about 95% of freshly formed radon progeny from the aerosol sample, and approximately 33% of partially aged progeny. Addition of an electrical condenser and a modified dichotomous virtual impactor are expected to produce considerable improvement in these numbers, the goal being to enrich the transuranic (TRU) fraction of the aerosols. This offers the possibility of improving the signal-to-noise ratio for the detected alpha-particle energy spectrum in the region of interest for detecting TRU materials associated with aerosols, thereby enhancing the performance of background-compensation algorithms for improving the quality of alarm signals intended to warn personnel of potentially harmful quantities of TRU materials in the ambient air.
Reporting of Numerical and Statistical Differences in Abstracts
Dryver, Eric; Hux, Janet E
2002-01-01
OBJECTIVE The reporting of relative risk reductions (RRRs) or absolute risk reductions (ARRs) to quantify binary outcomes in trials engenders differing perceptions of therapeutic efficacy, and the merits of P values versus confidence intervals (CIs) are also controversial. We describe the manner in which numerical and statistical difference in treatment outcomes is presented in published abstracts. DESIGN A descriptive study of abstracts published in 1986 and 1996 in 8 general medical and specialty journals. Inclusion criteria: controlled, intervention trials with a binary primary or secondary outcome. Seven items were recorded: raw data (outcomes for each treatment arm), measure of relative difference (e.g., RRR), ARR, number needed to treat, P value, CI, and verbal statement of statistical significance. The prevalence of these items was compared between journals and across time. RESULTS Of 5,293 abstracts, 300 met the inclusion criteria. In 1986, 60% of abstracts did not provide both the raw data and a corresponding P value or CI, while 28% failed to do so in 1Dr. Hux is a Career Scientist of the Ontario Ministry of Health and receives salary support from the Institute for Clinical Evaluative Sciences in Ontario.996 (P < .001; RRR of 53%; ARR of 32%; CI for ARR 21% to 43%). The variability between journals was highly significant (P < .001). In 1986, 100% of abstracts lacked a measure of absolute difference while 88% of 1996 abstracts did so (P < .001). In 1986, 98% of abstracts lacked a CI while 65% of 1996 abstracts did so (P < .001). CONCLUSIONS The provision of quantitative outcome and statistical quantitative information has significantly increased between 1986 and 1996. However, further progress can be made to make abstracts more informative. PMID:11929506
Journal Literature Covered by Physics Abstracts in 1965.
ERIC Educational Resources Information Center
Keenan, Stella; Brickwedde, F.G.
A study of the publications of the Physics Journal literature has been made, utilizing the 1965 issues of Physics Abstracts. It is intended to provide a profile of the physics literature and statistical information on physics abstract coverage. It deals with abstracts from serial (journal) publications and includes some 32,000 articles from 495…
Abstract and concrete categories? Evidences from neurodegenerative diseases.
Catricalà, Eleonora; Della Rosa, Pasquale A; Plebani, Valentina; Vigliocco, Gabriella; Cappa, Stefano F
2014-11-01
We assessed the performance of patients with a diagnosis of Alzheimer׳s disease (AD) and of the semantic variant of primary progressive aphasia (sv-PPA) in a series of tasks involving both abstract and concrete stimuli, which were controlled for most of the variables that have been shown to affect performance on lexical-semantic tasks. Our aims were to compare the patients׳ performance on abstract and concrete stimuli and to assess category-effects within the abstract and concrete domains. The results showed: (i) a better performance on abstract than concrete concepts in sv-PPA patients. (ii) Category-related effects in the abstract domain, with emotion concepts being preserved in AD and social relations being selectively impaired in sv-PPA. In addition, a living-non living dissociation may be (infrequently) observed in individual AD patients after controlling for an extensive set of potential confounds. Thus, differences between and within the concrete or abstract domain may be present in patients with semantic memory disorders, mirroring the different brain regions involved by the different pathologies. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Bervillier, C.; Boisseau, B.; Giacomini, H.
2008-02-01
The relation between the Wilson-Polchinski and the Litim optimized ERGEs in the local potential approximation is studied with high accuracy using two different analytical approaches based on a field expansion: a recently proposed genuine analytical approximation scheme to two-point boundary value problems of ordinary differential equations, and a new one based on approximating the solution by generalized hypergeometric functions. A comparison with the numerical results obtained with the shooting method is made. A similar accuracy is reached in each case. Both two methods appear to be more efficient than the usual field expansions frequently used in the current studies of ERGEs (in particular for the Wilson-Polchinski case in the study of which they fail).
ERIC Educational Resources Information Center
Proceedings of the ASIS Annual Meeting, 1996
1996-01-01
Includes abstracts of special interest group (SIG) sessions. Highlights include digital imagery; text summarization; browsing; digital libraries; icons and the Web; information management; curricula planning; interfaces; information systems; theories; scholarly and scientific communication; global development; archives; document delivery;…
Process improvement: a multi-registry database abstraction success story.
Abrich, Victor; Rokey, Roxann; Devadas, Christopher; Uebel, Julie
2014-01-01
The St. Joseph Hospital/Marshfield Clinic Cardiac Database Registry submits data to the National Cardiovascular Data Registry (NCDR) and to the Society of Thoracic Surgeons (STS) National Database. Delayed chart abstraction is problematic, since hospital policy prohibits patient care clarifications made to the medical record more than 1 month after hospital discharge. This can also lead to late identification of missed care opportunities and untimely notification to providers. Our institution was 3.5 months behind in retrospective postdischarge case abstraction. A process improvement plan was implemented to shorten this delay to 1 month postdischarge. Daily demand of incoming cases and abstraction capacity were determined for 4 employees. Demand was matched to capacity, with the remaining time allocated to reducing backlog. Daily demand of new cases was 17.1 hours. Daily abstraction capacity was 24 hours, assuming 6 hours of effective daily abstraction time per employee, leaving 7 hours per day for backlogged case abstraction. The predicted time to reach abstraction target was 10 weeks. This was accomplished after 10 weeks, as predicted, leading to a 60% reduction of backlogged cases. The delay of postdischarge chart abstraction was successfully shortened from 3.5 months to 1 month. We intend to maintain same-day abstraction efficiency without reaccumulating substantial backlog.
ERIC Educational Resources Information Center
Proceedings of the ASIS Annual Meeting, 1994
1994-01-01
Includes abstracts of 18 special interest group (SIG) sessions. Highlights include natural language processing, information science and terminology science, classification, knowledge-intensive information systems, information value and ownership issues, economics and theories of information science, information retrieval interfaces, fuzzy thinking…
Conference Abstracts: AEDS '84.
ERIC Educational Resources Information Center
Baird, William E.
1985-01-01
The Association of Educational Data Systems (AEDS) conference included 102 presentations. Abstracts of seven of these presentations are provided. Topic areas considered include LOGO, teaching probability through a computer game, writing effective computer assisted instructional materials, computer literacy, research on instructional…
ERIC Educational Resources Information Center
Proceedings of the ASIS Annual Meeting, 1993
1993-01-01
Presents abstracts of 34 special interest group (SIG) sessions. Highlights include humanities scholars and electronic texts; information retrieval and indexing systems design; automated indexing; domain analysis; query expansion in document retrieval systems; thesauri; business intelligence; Americans with Disabilities Act; management;…
An Approximate Approach to Automatic Kernel Selection.
Ding, Lizhong; Liao, Shizhong
2016-02-02
Kernel selection is a fundamental problem of kernel-based learning algorithms. In this paper, we propose an approximate approach to automatic kernel selection for regression from the perspective of kernel matrix approximation. We first introduce multilevel circulant matrices into automatic kernel selection, and develop two approximate kernel selection algorithms by exploiting the computational virtues of multilevel circulant matrices. The complexity of the proposed algorithms is quasi-linear in the number of data points. Then, we prove an approximation error bound to measure the effect of the approximation in kernel matrices by multilevel circulant matrices on the hypothesis and further show that the approximate hypothesis produced with multilevel circulant matrices converges to the accurate hypothesis produced with kernel matrices. Experimental evaluations on benchmark datasets demonstrate the effectiveness of approximate kernel selection.
Cosmic microwave background snapshots: pre-WMAP and post-WMAP.
Bond, J Richard; Contaldi, Carlo; Pogosyan, Dmitry
2003-11-15
We highlight the remarkable evolution in the cosmic microwave background (CMB) power spectrum C(l) as a function of multipole l over the past few years, and in the cosmological parameters for minimal inflation models derived from it: from anisotropy results before 2000; in 2000 and 2001 from Boomerang, Maxima and the Degree Angular Scale Interferometer (DASI), extending l to approximately 1000; and in 2002 from the Cosmic Background Imager (CBI), Very Small Array (VSA), ARCHEOPS and Arcminute Cosmology Bolometer Array Receiver (ACBAR), extending l to approximately 3000, with more from Boomerang and DASI as well. Pre-WMAP (pre-Wilkinson Microwave Anisotropy Probe) optimal band powers are in good agreement with each other and with the exquisite one-year WMAP results, unveiled in February 2003, which now dominate the l less, similar 600 bands. These CMB experiments significantly increased the case for accelerated expansion in the early Universe (the inflationary paradigm) and at the current epoch (dark energy dominance) when they were combined with "prior" probabilities on the parameters. The minimal inflation parameter set, [omega(b), omega(cdm), Omega(tot), Omega(Lambda), n(s), tau(C), sigma(8)], is applied in the same way to the evolving data. C(l) database and Monte Carlo Markov Chain (MCMC) methods are shown to give similar values, which are highly stable over time and for different prior choices, with the increasing precision best characterized by decreasing errors on uncorrelated "parameter eigenmodes". Priors applied range from weak ones to stronger constraints from the expansion rate (HST-h), from cosmic acceleration from supernovae (SN1) and from galaxy clustering, gravitational lensing and local cluster abundance (LSS). After marginalizing over the other cosmic and experimental variables for the weak + LSS prior, the pre-WMAP data of January 2003 compared with the post-WMAP data of March 2003 give Omega(tot) = 1.03(-0.04)(+0.05) compared with 1
Approximate error conjugation gradient minimization methods
Kallman, Jeffrey S
2013-05-21
In one embodiment, a method includes selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, calculating an approximate error using the subset of rays, and calculating a minimum in a conjugate gradient direction based on the approximate error. In another embodiment, a system includes a processor for executing logic, logic for selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, logic for calculating an approximate error using the subset of rays, and logic for calculating a minimum in a conjugate gradient direction based on the approximate error. In other embodiments, computer program products, methods, and systems are described capable of using approximate error in constrained conjugate gradient minimization problems.
Multi-variate joint PDF for non-Gaussianities: exact formulation and generic approximations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Verde, Licia; Jimenez, Raul; Alvarez-Gaume, Luis
2013-06-01
We provide an exact expression for the multi-variate joint probability distribution function of non-Gaussian fields primordially arising from local transformations of a Gaussian field. This kind of non-Gaussianity is generated in many models of inflation. We apply our expression to the non-Gaussianity estimation from Cosmic Microwave Background maps and the halo mass function where we obtain analytical expressions. We also provide analytic approximations and their range of validity. For the Cosmic Microwave Background we give a fast way to compute the PDF which is valid up to more than 7σ for f{sub NL} values (both true and sampled) not ruledmore » out by current observations, which consists of expressing the PDF as a combination of bispectrum and trispectrum of the temperature maps. The resulting expression is valid for any kind of non-Gaussianity and is not limited to the local type. The above results may serve as the basis for a fully Bayesian analysis of the non-Gaussianity parameter.« less
Content Abstract Classification Using Naive Bayes
NASA Astrophysics Data System (ADS)
Latif, Syukriyanto; Suwardoyo, Untung; Aldrin Wihelmus Sanadi, Edwin
2018-03-01
This study aims to classify abstract content based on the use of the highest number of words in an abstract content of the English language journals. This research uses a system of text mining technology that extracts text data to search information from a set of documents. Abstract content of 120 data downloaded at www.computer.org. Data grouping consists of three categories: DM (Data Mining), ITS (Intelligent Transport System) and MM (Multimedia). Systems built using naive bayes algorithms to classify abstract journals and feature selection processes using term weighting to give weight to each word. Dimensional reduction techniques to reduce the dimensions of word counts rarely appear in each document based on dimensional reduction test parameters of 10% -90% of 5.344 words. The performance of the classification system is tested by using the Confusion Matrix based on comparative test data and test data. The results showed that the best classification results were obtained during the 75% training data test and 25% test data from the total data. Accuracy rates for categories of DM, ITS and MM were 100%, 100%, 86%. respectively with dimension reduction parameters of 30% and the value of learning rate between 0.1-0.5.
Large-scale anisotropy of the cosmic microwave background radiation
NASA Technical Reports Server (NTRS)
Silk, J.; Wilson, M. L.
1981-01-01
Inhomogeneities in the large-scale distribution of matter inevitably lead to the generation of large-scale anisotropy in the cosmic background radiation. The dipole, quadrupole, and higher order fluctuations expected in an Einstein-de Sitter cosmological model have been computed. The dipole and quadrupole anisotropies are comparable to the measured values, and impose important constraints on the allowable spectrum of large-scale matter density fluctuations. A significant dipole anisotropy is generated by the matter distribution on scales greater than approximately 100 Mpc. The large-scale anisotropy is insensitive to the ionization history of the universe since decoupling, and cannot easily be reconciled with a galaxy formation theory that is based on primordial adiabatic density fluctuations.
Reionization and the cosmic microwave background in an open universe
NASA Technical Reports Server (NTRS)
Persi, Fred M.
1995-01-01
If the universe was reionized at high reshift (z greater than or approximately equal to 30) or never recombined, then photon-electron scattering can erase fluctuations in the cosmic microwave background at scales less than or approximately equal to 1 deg. Peculiar motion at the surface of last scattering will then have given rise to new anisotropy at the 1 min level through the Vishniac effect. Here the observed fluctuations in galaxy counts are extrapolated to high redshifts using linear theory, and the expected anisotropy is computed. The predicted level of anisotropies is a function of Omega(sub 0) and the ratio of the density in ionized baryons to the critical density and is shown to depend strongly on the large- and small-scale power. It is not possible to make general statements about the viability of all reionized models based on current observations, but it is possible to rule out specific models for structure formation, particularly those with high baryonic content or small-scale power. The induced fluctuations are shown to scale with cosmological parameters and optical depth.
Homicide in the western family and background factors of a perpetrator.
Aho, Anna Liisa; Remahl, Anni; Paavilainen, Eija
2017-07-01
Familicide is a multiple-victim homicide incident in which the killer's spouse and one or more children are slain. A systematic review was conducted to reveal the background factors of western homicide perpetrators. The systematic search was performed in the Arto, Medic, Cinahl, Medline, EBSCOhost Academic Search Premier and Social Services abstracts databases. The keywords were familicide, family homicide, familicide-suicide, filicide-suicide, extended suicide, child, murder, family, filicide and infanticide. The searches revealed 4139 references from the databases. The references were filtered and 32 peer-reviewed research articles revealed in years 2004-2014 were selected as data. The articles were analysed using inductive content analysis, by finding all possible background factors related to homicide. The factors were described as percentages of the range. The background factors of familicide perpetrators were categorised as follows: perpetrators who had committed homicide of a child and intimate partner and possibly committed suicide; a father had who killed a child; a mother who had killed a child; a father who had committed a filicide-suicide; and a mother who had committed a filicide-suicide. Psychological instability, violence and crime were found in all these categories of familicides. Perpetrators who had committed a suicide in addition to the familicide had more often been diagnosed with depression, but they sought treatment for mental health problems less often and had violence and self-destructiveness less often in their background than in other familicide categories. Social and healthcare professionals should be more sensitive to emerging family problems and be prepared for intervention.
Feedback Form for the ADS Abstract Service
ADS Feedback Form for the ADS Abstract Service Please use this form to report bugs or send comments to the ADS Abstract Project. Thank you for your feedback. â Required field Your Name: â Your E
Argument structure and the representation of abstract semantics.
Rodríguez-Ferreiro, Javier; Andreu, Llorenç; Sanz-Torrent, Mònica
2014-01-01
According to the dual coding theory, differences in the ease of retrieval between concrete and abstract words are related to the exclusive dependence of abstract semantics on linguistic information. Argument structure can be considered a measure of the complexity of the linguistic contexts that accompany a verb. If the retrieval of abstract verbs relies more on the linguistic codes they are associated to, we could expect a larger effect of argument structure for the processing of abstract verbs. In this study, sets of length- and frequency-matched verbs including 40 intransitive verbs, 40 transitive verbs taking simple complements, and 40 transitive verbs taking sentential complements were presented in separate lexical and grammatical decision tasks. Half of the verbs were concrete and half were abstract. Similar results were obtained in the two tasks, with significant effects of imageability and transitivity. However, the interaction between these two variables was not significant. These results conflict with hypotheses assuming a stronger reliance of abstract semantics on linguistic codes. In contrast, our data are in line with theories that link the ease of retrieval with availability and robustness of semantic information.
Giegerich, Robert; Voss, Björn; Rehmsmeier, Marc
2004-01-01
The function of a non-protein-coding RNA is often determined by its structure. Since experimental determination of RNA structure is time-consuming and expensive, its computational prediction is of great interest, and efficient solutions based on thermodynamic parameters are known. Frequently, however, the predicted minimum free energy structures are not the native ones, leading to the necessity of generating suboptimal solutions. While this can be accomplished by a number of programs, the user is often confronted with large outputs of similar structures, although he or she is interested in structures with more fundamental differences, or, in other words, with different abstract shapes. Here, we formalize the concept of abstract shapes and introduce their efficient computation. Each shape of an RNA molecule comprises a class of similar structures and has a representative structure of minimal free energy within the class. Shape analysis is implemented in the program RNAshapes. We applied RNAshapes to the prediction of optimal and suboptimal abstract shapes of several RNAs. For a given energy range, the number of shapes is considerably smaller than the number of structures, and in all cases, the native structures were among the top shape representatives. This demonstrates that the researcher can quickly focus on the structures of interest, without processing up to thousands of near-optimal solutions. We complement this study with a large-scale analysis of the growth behaviour of structure and shape spaces. RNAshapes is available for download and as an online version on the Bielefeld Bioinformatics Server.
AAVSO and the International Year of Light (Poster abstract)
NASA Astrophysics Data System (ADS)
Larsen, K.
2015-06-01
(Abstract only) The United Nations General Assembly has officially designated 2015 to be the International Year of Light (IYL). Modeled in part on the earlier International Year of Astronomy (IYA), this cross-disciplinary, international educational and outreach project will celebrate the importance of light in science, technology, cultural heritage, and the arts. It ties in with several important anniversaries, such as the 1000th anniversary of the publication of Ibn Al Haythem's “Book of Optics,” the 150th anniversary of Maxwell's equations of electromagnetism, the centenary of Einstein's General Theory of Relativity, and the 50th anniversary of the discovery of the Cosmic Microwave Background Radiation. Because variable stars are defined as such due to the variability of the light we observe from them, all of the AAVSO programs, regardless of type of variable or instrumentation (eye, DSLR, PEP, or CCD) have natural tie-ins to the study of light. This poster will highlight a number of specific ways that AAVSO members and the organization as a whole can become intimately involved with this unique outreach opportunity.
Valderrama-Zurián, Juan Carlos; Bolaños-Pizarro, Máxima; Bueno-Cañigral, Francisco Jesús; Álvarez, F Javier; Ontalba-Ruipérez, José Antonio; Aleixandre-Benavent, Rafael
2009-01-01
Background Subsequent publication rate of abstracts presented at meetings is seen as an indicator of the interest and quality of the meeting. We have analyzed characteristics and rate publication in peer-reviewed journals derived from oral communications and posters presented at the 1999 College on Problems of Drug Dependence (CPDD) meeting. Methods All 689 abstracts presented at the 1999 CPDD meeting were reviewed. In order to find the existence of publications derived from abstracts presented at that meeting, a set of bibliographical searches in the database Medline was developed in July 2006. Information was gathered concerning the abstracts, articles and journals in which they were published. Results 254 out of 689 abstracts (36.9%) gave rise to at least one publication. The oral communications had a greater likelihood of being published than did the posters (OR = 2.53, 95% CI 1.80-3.55). The average time lapse to publication of an article was 672.97 days. The number of authors per work in the subsequent publications was 4.55. The articles were published in a total of 84 journals, of which eight were indexed with the subject term Substance-Related Disorders. Psychopharmacology (37 articles, 14.5%) was the journal that published the greatest number of articles subsequent to the abstracts presented at the 1999 CPDD meeting. Conclusion One out of every three abstracts presented to the 1999 CPDD meeting were later published in peer-reviewed journals indexed in Medline. The subsequent publication of the abstracts presented in the CPDD meetings should be actively encouraged, as this maximizes the dissemination of the scientific research and therefore the investment. PMID:19889211
Compendium of abstracts on statistical applications in geotechnical engineering
NASA Astrophysics Data System (ADS)
Hynes-Griffin, M. E.; Deer, G. W.
1983-09-01
The results of a literature search of geotechnical and statistical abstracts are presented in tables listing specific topics, title of the abstract, main author and the file number under which the abstract can be found.
Composing Interfering Abstract Protocols
2016-04-01
Tecnologia , Universidade Nova de Lisboa, Caparica, Portugal. This document is a companion technical report of the paper, “Composing Interfering Abstract...a Ciência e Tecnologia (Portuguese Foundation for Science and Technology) through the Carnegie Mellon Portugal Program under grant SFRH / BD / 33765
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.
Bilingual Vocational Education. Project Abstracts 1987-1988.
ERIC Educational Resources Information Center
Office of Vocational and Adult Education (ED), Washington, DC.
Abstracts are provided for 16 bilingual vocational education projects offered in 1987-88. Each abstract provides information on: grantee; state; project title; project director, address, and telephone number; project officer and U.S. Department of Education address; language group(s) served; occupational skills area(s); length of training cycle…
Properties of magnetized Coulomb crystals of ions with polarizable electron background
NASA Astrophysics Data System (ADS)
Kozhberov, A. A.
2018-06-01
We have studied phonon and thermodynamic properties of a body-centered cubic (bcc) Coulomb crystal of ions with weakly polarized electron background in a uniform magnetic field B. At B = 0, the difference between phonon moments calculated using the Thomas-Fermi (TF) and random phase approximations is always less than 1% and for description of phonon properties of a crystal, TF formalism was used. This formalism was successfully applied to investigate thermodynamic properties of magnetized Coulomb crystals. It was shown that the influence of the polarization of the electron background is significant only at κ TF a > 0.1 and T ≪ T p ( 1 + h2 ) - 1 / 2 , where κTF is the Thomas-Fermi wavenumber, a is the ion sphere radius, T p ≡ ℏ ω p is the ion plasma temperature, h ≡ ω B / ω p , ωB is the ion cyclotron frequency, and ωp is the ion plasma frequency.
Preparing and presenting effective abstracts and posters in psychiatry
Singh, Manpreet K.
2014-01-01
Presenting an abstract and a poster gives scientists from all fields, including psychiatry, an important opportunity to introduce their research to others. Researchers and mental health professionals at all levels of career development can use several media resources to assist them with the technical aspects of preparing an abstract or a poster. This article will focus on major principles associated with preparing and presenting an abstract and a poster at a scientific meeting. A literature search using NIH PubMed was conducted to identify peer and non-peer-reviewed articles that provide methods for effective abstract and poster presentation for the period of 1966 to June 2014. First, we review the purpose and relative importance of abstracts and posters in academic settings. Next, we describe the qualities of an effective abstract and poster and common pitfalls that may occur. Finally, we present a systematic approach to preparing and presenting an abstract and a poster in a scientific setting. Several sources consistently suggest that readability, organization, and succinctness are qualities that make an effective and successful abstract and poster. Mental health professionals in all stages of their career development may benefit from following these guidelines in presenting their scientific work. PMID:25085499
Subsequent publication of oral and maxillofacial surgery meeting abstracts.
Rodriguez, Joseph L; Laskin, Daniel M
2012-05-01
Previous studies in various medical specialties have shown that fewer than 50% of abstracts presented at meetings are subsequently published. The purpose of the present study was to determine the publication rate of abstracts presented at the annual meetings of the American Association of Oral and Maxillofacial Surgeons. The titles and authors of the abstracts from all oral abstract session presentations and posters by American contributors were collected from the Final Programs of the American Association of Oral and Maxillofacial Surgeons annual meetings for 2006 to 2009. A PubMed search for published articles through December 2010 was then performed using the authors' names, abstract titles, and key words. A total of 311 abstract presentations were done at the 4 annual meetings. Of these, only 85 (24%) were subsequently published. No difference was found between abstracts from oral or poster presentations. Most of the articles were published in the Journal of Oral and Maxillofacial Surgery. Because of deficiencies that can occur in abstracts and the need to disseminate the information they contain, it is important to take the appropriate measures to ensure that full articles are subsequently published. Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Preparing and presenting effective abstracts and posters in psychiatry.
Singh, Manpreet K
2014-12-01
Presenting an abstract and a poster gives scientists from all fields, including psychiatry, an important opportunity to introduce their research to others. Researchers and mental health professionals at all levels of career development can use several media resources to assist them with the technical aspects of preparing an abstract or a poster. This article will focus on major principles associated with preparing and presenting an abstract and a poster at a scientific meeting. A literature search using NIH PubMed was conducted to identify peer and nonpeer-reviewed articles that provide methods for effective abstract and poster presentation for the period of 1966 to June 2014. First, the author reviews the purpose and relative importance of abstracts and posters in academic settings. Next, the author describes the qualities of an effective abstract and poster and common pitfalls that may occur. Finally, the author presents a systematic approach to preparing and presenting an abstract and a poster in a scientific setting. Several sources consistently suggest that readability, organization, and succinctness are qualities that make an effective and successful abstract and poster. Mental health professionals in all stages of their career development may benefit from following these guidelines in presenting their scientific work.
NASA Astrophysics Data System (ADS)
Isomura, Noritake; Cui, Yi-Tao; Murai, Takaaki; Oji, Hiroshi; Kimoto, Yasuji
2017-07-01
In Auger electron spectroscopy (AES), the spectral background is mainly due to inelastic scattering of Auger electrons that lose their kinetic energy in a sample bulk. To investigate the spectral components within this background for SiO2(19.3 nm)/Si(100) with known layer thickness, X-ray absorption spectroscopy (XAS) was used in the partial-electron-yield (PEY) mode at several electron kinetic energies to probe the background of the Si KLL Auger peak. The Si K-edge PEY-XAS spectra constituted of both Si and SiO2 components at each kinetic energy, and their component fractions were approximately the same as those derived from the simulated AES background for the same sample structure. The contributions of Auger electrons originating from layers at different depths to the inelastic background could thus be identified experimentally.
Galievsky, Victor A; Stasheuski, Alexander S; Krylov, Sergey N
2017-10-17
The limit-of-detection (LOD) in analytical instruments with fluorescence detection can be improved by reducing noise of optical background. Efficiently reducing optical background noise in systems with spectrally nonuniform background requires complex optimization of an emission filter-the main element of spectral filtration. Here, we introduce a filter-optimization method, which utilizes an expression for the signal-to-noise ratio (SNR) as a function of (i) all noise components (dark, shot, and flicker), (ii) emission spectrum of the analyte, (iii) emission spectrum of the optical background, and (iv) transmittance spectrum of the emission filter. In essence, the noise components and the emission spectra are determined experimentally and substituted into the expression. This leaves a single variable-the transmittance spectrum of the filter-which is optimized numerically by maximizing SNR. Maximizing SNR provides an accurate way of filter optimization, while a previously used approach based on maximizing a signal-to-background ratio (SBR) is the approximation that can lead to much poorer LOD specifically in detection of fluorescently labeled biomolecules. The proposed filter-optimization method will be an indispensable tool for developing new and improving existing fluorescence-detection systems aiming at ultimately low LOD.
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,…
Non-Gaussian microwave background fluctuations from nonlinear gravitational effects
NASA Technical Reports Server (NTRS)
Salopek, D. S.; Kunstatter, G. (Editor)
1991-01-01
Whether the statistics of primordial fluctuations for structure formation are Gaussian or otherwise may be determined if the Cosmic Background Explorer (COBE) Satellite makes a detection of the cosmic microwave-background temperature anisotropy delta T(sub CMB)/T(sub CMB). Non-Gaussian fluctuations may be generated in the chaotic inflationary model if two scalar fields interact nonlinearly with gravity. Theoretical contour maps are calculated for the resulting Sachs-Wolfe temperature fluctuations at large angular scales (greater than 3 degrees). In the long-wavelength approximation, one can confidently determine the nonlinear evolution of quantum noise with gravity during the inflationary epoch because: (1) different spatial points are no longer in causal contact; and (2) quantum gravity corrections are typically small-- it is sufficient to model the system using classical random fields. If the potential for two scalar fields V(phi sub 1, phi sub 2) possesses a sharp feature, then non-Gaussian fluctuations may arise. An explicit model is given where cold spots in delta T(sub CMB)/T(sub CMB) maps are suppressed as compared to the Gaussian case. The fluctuations are essentially scale-invariant.
NASA Technical Reports Server (NTRS)
Merrill, W. C.
1978-01-01
The Routh approximation technique for reducing the complexity of system models was applied in the frequency domain to a 16th order, state variable model of the F100 engine and to a 43d order, transfer function model of a launch vehicle boost pump pressure regulator. The results motivate extending the frequency domain formulation of the Routh method to the time domain in order to handle the state variable formulation directly. The time domain formulation was derived and a characterization that specifies all possible Routh similarity transformations was given. The characterization was computed by solving two eigenvalue-eigenvector problems. The application of the time domain Routh technique to the state variable engine model is described, and some results are given. Additional computational problems are discussed, including an optimization procedure that can improve the approximation accuracy by taking advantage of the transformation characterization.
Assume-Guarantee Abstraction Refinement Meets Hybrid Systems
NASA Technical Reports Server (NTRS)
Bogomolov, Sergiy; Frehse, Goran; Greitschus, Marius; Grosu, Radu; Pasareanu, Corina S.; Podelski, Andreas; Strump, Thomas
2014-01-01
Compositional verification techniques in the assume- guarantee style have been successfully applied to transition systems to efficiently reduce the search space by leveraging the compositional nature of the systems under consideration. We adapt these techniques to the domain of hybrid systems with affine dynamics. To build assumptions we introduce an abstraction based on location merging. We integrate the assume-guarantee style analysis with automatic abstraction refinement. We have implemented our approach in the symbolic hybrid model checker SpaceEx. The evaluation shows its practical potential. To the best of our knowledge, this is the first work combining assume-guarantee reasoning with automatic abstraction-refinement in the context of hybrid automata.
Innovation Abstracts: Volume XI, Numbers 1-30.
ERIC Educational Resources Information Center
Roueche, Suanne D., Ed.
1989-01-01
This series of one- to two-page abstracts highlights a variety of innovative approaches to teaching and learning in the community college. Topics covered in the abstracts include: (1) cooperative planning for institutional excellence; (2) rewarding scholarship among community college faculty; (3) in-class debates as a learning strategy; (4)…
Variational dynamic background model for keyword spotting in handwritten documents
NASA Astrophysics Data System (ADS)
Kumar, Gaurav; Wshah, Safwan; Govindaraju, Venu
2013-12-01
We propose a bayesian framework for keyword spotting in handwritten documents. This work is an extension to our previous work where we proposed dynamic background model, DBM for keyword spotting that takes into account the local character level scores and global word level scores to learn a logistic regression classifier to separate keywords from non-keywords. In this work, we add a bayesian layer on top of the DBM called the variational dynamic background model, VDBM. The logistic regression classifier uses the sigmoid function to separate keywords from non-keywords. The sigmoid function being neither convex nor concave, exact inference of VDBM becomes intractable. An expectation maximization step is proposed to do approximate inference. The advantage of VDBM over the DBM is multi-fold. Firstly, being bayesian, it prevents over-fitting of data. Secondly, it provides better modeling of data and an improved prediction of unseen data. VDBM is evaluated on the IAM dataset and the results prove that it outperforms our prior work and other state of the art line based word spotting system.
NASA Astrophysics Data System (ADS)
Ballestrero, Alessandro; Maina, Ezio
1991-10-01
The reaction pp→ t t¯γγ is studied for 80⩽ Mγγ⩽140 GeV, as a possible background to the detection of an intermedia te mass standard model Higgs in the rare ℓ νγγ final state. If the top is not too heavy the prompt photon production, integrated over a window of 6 GeV in Mγγ around the Higgs mass, can be larger than the production of photon pairs from Higgs decay. Standard isolation cuts can effectively dispose of this background for mt⩾150 GeV. For mt∼100 GeV approximately the same nu mber of background and signal events pass the cuts.
Abstract processing and observer vantage perspective in dysphoria.
Hart-Smith, Ly; Moulds, Michelle L
2018-05-07
processing and observer vantage perspective have been associated with negative consequences in depression. We investigated the relationship between mode of processing and vantage perspective bidirectionally in high and low dysphoric individuals, using abstract and concrete descriptions of experimenter-provided everyday actions. When vantage perspective was manipulated and processing mode was measured (Study 1a), participants who adopted a field perspective did not differ from those who adopted an observer perspective in their preference for abstract descriptions, irrespective of dysphoria status. When processing mode was manipulated and vantage perspective was measured (Study 1b), participants provided with abstract descriptions had a greater tendency to adopt an observer perspective than those provided with concrete descriptions, irrespective of dysphoria status. These results were replicated in larger online samples (Studies 2a and 2b). Together, they indicate a unidirectional causal relationship, whereby processing mode causally influences vantage perspective, in contrast to the bidirectional relationship previously reported in an unselected sample (Libby, Shaeffer, & Eibach, 2009). Further, these findings demonstrate that abstract processing increases the likelihood of adopting an observer perspective, and support targeting abstract processing in the treatment of depression to address the negative consequences associated with both abstract processing and recalling/imagining events from an observer perspective. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
The lexical processing of abstract and concrete nouns.
Papagno, Costanza; Fogliata, Arianna; Catricalà, Eleonora; Miniussi, Carlo
2009-03-31
Recent activation studies have suggested different neural correlates for processing concrete and abstract words. However, the precise localization is far from being defined. One reason for the heterogeneity of these results could lie in the extreme variability of experimental paradigms, ranging from explicit semantic judgments to lexical decision tasks (auditory and/or visual). The present study explored the processing of abstract/concrete nouns by using repetitive Transcranial Magnetic Stimulation (rTMS) and a lexical decision paradigm in neurologically-unimpaired subjects. Four sites were investigated: left inferior frontal, bilaterally posterior-superior temporal and left posterior-inferior parietal. An interference on accuracy was found for abstract words when rTMS was applied over the left temporal site, while for concrete words accuracy decreased when rTMS was applied over the right temporal site. Accuracy for abstract words, but not for concrete words, decreased after frontal stimulation as compared to the sham condition. These results suggest that abstract lexical entries are stored in the posterior part of the left temporal superior gyrus and possibly in the left frontal inferior gyrus, while the regions involved in storing concrete items include the right temporal cortex. It cannot be excluded, however, that additional areas, not tested in this experiment, are involved in processing both, concrete and abstract nouns.
ERIC Educational Resources Information Center
Sakhnini, Victoria; Hazzan, Orit
2008-01-01
The research presented in this article deals with the difficulties and mental processes involved in the definition, implementation, and use of abstract data types encountered by 12th grade advanced-level computer science students. Research findings are interpreted within the theoretical framework of "reducing abstraction" [Hazzan 1999]. The…
Poster Session- Extended Abstracts
Jack D. Alexander III; Jean Findley; Brenda K. Kury; Jan L. Beyers; Douglas S. Cram; Terrell T. Baker; Jon C. Boren; Carl Edminster; Sue A. Ferguson; Steven McKay; David Nagel; Trent Piepho; Miriam Rorig; Casey Anderson; Jeanne Hoadley; Paulette L. Ford; Mark C. Andersen; Ed L. Fredrickson; Joe Truett; Gary W. Roemer; Brenda K. Kury; Jennifer Vollmer; Christine L. May; Danny C. Lee; James P. Menakis; Robert E. Keane; Zhi-Liang Zhu; Carol Miller; Brett Davis; Katharine Gray; Ken Mix; William P. Kuvlesky Jr.; D. Lynn Drawe; Marcia G. Narog; Roger D. Ottmar; Robert E. Vihnanek; Clinton S. Wright; Timothy E. Paysen; Burton K. Pendleton; Rosemary L. Pendleton; Carleton S. White; John Rogan; Doug Stow; Janet Franklin; Jennifer Miller; Lisa Levien; Chris Fischer; Emma Underwood; Robert Klinger; Peggy Moore; Clinton S. Wright
2008-01-01
Titles found within Poster Session-Extended Abstracts include:Assessment of emergency fire rehabilitation of four fires from the 2000 fire season on the Vale, Oregon, BLM district: review of the density sampling materials and methods: p. 329Â Growth of regreen, seeded for erosion control, in the...
Constructing Abstraction Hierarchies Using a Skill-Symbol Loop
Konidaris, George
2017-01-01
We describe a framework for building abstraction hierarchies whereby an agent alternates skill- and representation-construction phases to construct a sequence of increasingly abstract Markov decision processes. Our formulation builds on recent results showing that the appropriate abstract representation of a problem is specified by the agent’s skills. We describe how such a hierarchy can be used for fast planning, and illustrate the construction of an appropriate hierarchy for the Taxi domain. PMID:28579718
Analysis of corrections to the eikonal approximation
NASA Astrophysics Data System (ADS)
Hebborn, C.; Capel, P.
2017-11-01
Various corrections to the eikonal approximations are studied for two- and three-body nuclear collisions with the goal to extend the range of validity of this approximation to beam energies of 10 MeV/nucleon. Wallace's correction does not improve much the elastic-scattering cross sections obtained at the usual eikonal approximation. On the contrary, a semiclassical approximation that substitutes the impact parameter by a complex distance of closest approach computed with the projectile-target optical potential efficiently corrects the eikonal approximation. This opens the possibility to analyze data measured down to 10 MeV/nucleon within eikonal-like reaction models.
Title I, Higher Education Act Program Abstracts.
ERIC Educational Resources Information Center
Miller, Lorna M., Ed.
The 1979 edition of the Title I, Higher Education Act Program Abstracts is presented. Directed toward state Title I, HEA administrators, the program abstracts are made available in order to encourage nationwide program replication of those tested and evaluated programs that have been conducted with Title I support by institutions of higher…
Approximations of Two-Attribute Utility Functions
1976-09-01
preferred to") be a bina-zy relation on the set • of simple probability measures or ’gambles’ defined on a set T of consequences. Throughout this study it...simplifying independence assumptions. Although there are several approaches to this problem, the21 present study will focus on approximations of u... study will elicit additional interest in the topic. 2. REMARKS ON APPROXIMATION THEORY This section outlines a few basic ideas of approximation theory
Youssef, Joseph El; Engle, Julia M.; Massoud, Ryan G.; Ward, W. Kenneth
2010-01-01
Abstract Background A cause of suboptimal accuracy in amperometric glucose sensors is the presence of a background current (current produced in the absence of glucose) that is not accounted for. We hypothesized that a mathematical correction for the estimated background current of a commercially available sensor would lead to greater accuracy compared to a situation in which we assumed the background current to be zero. We also tested whether increasing the frequency of sensor calibration would improve sensor accuracy. Methods This report includes analysis of 20 sensor datasets from seven human subjects with type 1 diabetes. Data were divided into a training set for algorithm development and a validation set on which the algorithm was tested. A range of potential background currents was tested. Results Use of the background current correction of 4 nA led to a substantial improvement in accuracy (improvement of absolute relative difference or absolute difference of 3.5–5.5 units). An increase in calibration frequency led to a modest accuracy improvement, with an optimum at every 4 h. Conclusions Compared to no correction, a correction for the estimated background current of a commercially available glucose sensor led to greater accuracy and better detection of hypoglycemia and hyperglycemia. The accuracy-optimizing scheme presented here can be implemented in real time. PMID:20879968
Possibilities of identifying cyber attack in noisy space of n-dimensional abstract system
NASA Astrophysics Data System (ADS)
Jašek, Roman; Dvořák, Jiří; Janková, Martina; Sedláček, Michal
2016-06-01
This article briefly mentions some selected options of current concept for identifying cyber attacks from the perspective of the new cyberspace of real system. In the cyberspace, there is defined n-dimensional abstract system containing elements of the spatial arrangement of partial system elements such as micro-environment of cyber systems surrounded by other suitably arranged corresponding noise space. This space is also gradually supplemented by a new image of dynamic processes in a discreet environment, and corresponding again to n-dimensional expression of time space defining existence and also the prediction for expected cyber attacksin the noise space. Noises are seen here as useful and necessary for modern information and communication technologies (e.g. in processes of applied cryptography in ICT) and then the so-called useless noises designed for initial (necessary) filtering of this highly aggressive environment and in future expectedly offensive background in cyber war (e.g. the destruction of unmanned means of an electromagnetic pulse, or for destruction of new safety barriers created on principles of electrostatic field or on other principles of modern physics, etc.). The key to these new options is the expression of abstract systems based on the models of microelements of cyber systems and their hierarchical concept in structure of n-dimensional system in given cyberspace. The aim of this article is to highlight the possible systemic expression of cyberspace of abstract system and possible identification in time-spatial expression of real environment (on microelements of cyber systems and their surroundings with noise characteristics and time dimension in dynamic of microelements' own time and externaltime defined by real environment). The article was based on a partial task of faculty specific research.
Born approximation in linear-time invariant system
NASA Astrophysics Data System (ADS)
Gumjudpai, Burin
2017-09-01
An alternative way of finding the LTI’s solution with the Born approximation, is investigated. We use Born approximation in the LTI and in the transformed LTI in form of Helmholtz equation. General solution are considered as infinite series or Feynman graph. Slow-roll approximation are explored. Transforming the LTI system into Helmholtz equation, approximated general solution can be found for any given forms of force with its initial value.
Abstracts of BESRL Research Publications, FY 1969.
ERIC Educational Resources Information Center
Brown, Emma E.
Publications abstracted include Technical Research Reports 1156 and 1157, Technical Research Notes 199 through 210, Research Studies 68-4 through 68-6 and 69-1 through 6910, and Research Memorandums 68-8 through 68-13. Included are descriptions of 19 Work Units covering activities reported in the 33 abstracted publications, a list of regular…
Parent Education: Abstract Bibliography.
ERIC Educational Resources Information Center
Kremer, Barbara, Comp.
This bibliography has been compiled to alert educators to parent education documents found in the ERIC microfiche collection and in journal literature. Abstracts of selected documents have been taken from "Research in Education (RIE)", and journal article citations from the "Current Index to Journals in Education (CIJE)". Included are published…
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)
Approximate Model of Zone Sedimentation
NASA Astrophysics Data System (ADS)
Dzianik, František
2011-12-01
The process of zone sedimentation is affected by many factors that are not possible to express analytically. For this reason, the zone settling is evaluated in practice experimentally or by application of an empirical mathematical description of the process. The paper presents the development of approximate model of zone settling, i.e. the general function which should properly approximate the behaviour of the settling process within its entire range and at the various conditions. Furthermore, the specification of the model parameters by the regression analysis of settling test results is shown. The suitability of the model is reviewed by graphical dependencies and by statistical coefficients of correlation. The approximate model could by also useful on the simplification of process design of continual settling tanks and thickeners.
Energy conservation - A test for scattering approximations
NASA Technical Reports Server (NTRS)
Acquista, C.; Holland, A. C.
1980-01-01
The roles of the extinction theorem and energy conservation in obtaining the scattering and absorption cross sections for several light scattering approximations are explored. It is shown that the Rayleigh, Rayleigh-Gans, anomalous diffraction, geometrical optics, and Shifrin approximations all lead to reasonable values of the cross sections, while the modified Mie approximation does not. Further examination of the modified Mie approximation for the ensembles of nonspherical particles reveals additional problems with that method.
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…
Baulig, Christine; Krummenauer, Frank; Geis, Berit; Tulka, Sabrina; Knippschild, Stephanie
2018-05-22
To assess the reporting quality of randomised controlled trial (RCT) abstracts on age-related macular degeneration (AMD) healthcare, to evaluate the adherence to the Consolidated Standards of Reporting Trials (CONSORT) statement's recommendations on minimum abstract information and to identify journal characteristics associated with abstract reporting quality. Cross-sectional evaluation of RCT abstracts on AMD healthcare. A PubMed search was implemented to identify RCT abstracts on AMD healthcare published in the English language between January 2004 and December 2013. Data extraction was performed by two parallel readers independently by means of a documentation format in accordance with the 16 items of the CONSORT checklist for abstracts. The total number of criteria fulfilled by an abstract was derived as primary endpoint of the investigation; incidence rate ratios (IRRs) with unadjusted 95% CI were estimated by means of multiple Poisson regression to identify journal and article characteristics (publication year, multicentre design, structured abstract recommendations, effective sample size, effective abstract word counts and journal impact factor) possibly associated with the total number of fulfilled items. 136 of 673 identified abstracts (published in 36 different journals) fulfilled all eligibility criteria. The median number of fulfilled items was 7 (95% CI 7 to 8). No abstract reported all 16 recommended items; the maximum total number was 14, the minimum 3 of 16 items. Multivariate analysis only demonstrated the abstracts' word counts as being significantly associated with a better reporting of abstracts (Poisson regression-based IRR 1.002, 95% CI 1.001 to 1.003). Reporting quality of RCT abstracts on AMD investigations showed a considerable potential for improvement to meet the CONSORT abstract reporting recommendations. Furthermore, word counts of abstracts were identified as significantly associated with the overall abstract reporting quality.
Recognition of computerized facial approximations by familiar assessors.
Richard, Adam H; Monson, Keith L
2017-11-01
Studies testing the effectiveness of facial approximations typically involve groups of participants who are unfamiliar with the approximated individual(s). This limitation requires the use of photograph arrays including a picture of the subject for comparison to the facial approximation. While this practice is often necessary due to the difficulty in obtaining a group of assessors who are familiar with the approximated subject, it may not accurately simulate the thought process of the target audience (friends and family members) in comparing a mental image of the approximated subject to the facial approximation. As part of a larger process to evaluate the effectiveness and best implementation of the ReFace facial approximation software program, the rare opportunity arose to conduct a recognition study using assessors who were personally acquainted with the subjects of the approximations. ReFace facial approximations were generated based on preexisting medical scans, and co-workers of the scan donors were tested on whether they could accurately pick out the approximation of their colleague from arrays of facial approximations. Results from the study demonstrated an overall poor recognition performance (i.e., where a single choice within a pool is not enforced) for individuals who were familiar with the approximated subjects. Out of 220 recognition tests only 10.5% resulted in the assessor selecting the correct approximation (or correctly choosing not to make a selection when the array consisted only of foils), an outcome that was not significantly different from the 9% random chance rate. When allowed to select multiple approximations the assessors felt resembled the target individual, the overall sensitivity for ReFace approximations was 16.0% and the overall specificity was 81.8%. These results differ markedly from the results of a previous study using assessors who were unfamiliar with the approximated subjects. Some possible explanations for this disparity in
Consistent Yokoya-Chen Approximation to Beamstrahlung(LCC-0010)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peskin, M
2004-04-22
I reconsider the Yokoya-Chen approximate evolution equation for beamstrahlung and modify it slightly to generate simple, consistent analytical approximations for the electron and photon energy spectra. I compare these approximations to previous ones, and to simulation data.I reconsider the Yokoya-Chen approximate evolution equation for beamstrahlung and modify it slightly to generate simple, consistent analytical approximations for the electron and photon energy spectra. I compare these approximations to previous ones, and to simulation data.
Atypical associations to abstract words in Broca's aphasia.
Roll, Mikael; Mårtensson, Frida; Sikström, Sverker; Apt, Pia; Arnling-Bååth, Rasmus; Horne, Merle
2012-09-01
Left frontal brain lesions are known to give rise to aphasia and impaired word associations. These associations have previously been difficult to analyze. We used a semantic space method to investigate associations to cue words. The degree of abstractness of the generated words and semantic similarity to the cue words were measured. Three subjects diagnosed with Broca's aphasia and twelve control subjects associated freely to cue words. Results were evaluated with latent semantic analysis (LSA) applied to the Swedish Parole corpus. The aphasic subjects could be clearly distinguished from controls by a lower degree of abstractness in the words they generated. The aphasic group's associations showed a negative correlation between semantic similarity to cue word and abstractness of cue word. By developing novel semantic measures, we showed that Broca's aphasic subjects' word production was characterized by a low degree of abstractness and low degree of coherence in associations to abstract cue words. The results support models where meanings of concrete words are represented in neural networks involving perceptual and motor areas, whereas the meaning of abstract words is more dependent on connections to other word forms in the left frontal region. Semantic spaces can be used in future developments of evaluative tools for both diagnosis and research purposes. Copyright © 2011 Elsevier Srl. All rights reserved.
Calibration of a Background Oriented Schlieren (BOS) Set-up
NASA Astrophysics Data System (ADS)
Porta, David; Echeverría, Carlos; Cardoso, Hiroki; Aguayo, Alejandro; Stern, Catalina
2014-11-01
We use two materials with different known indexes of refraction to calibrate a Background Oriented Schlieren (BOS) experimental set-up, and to validate the Lorenz-Lorentz equation. BOS is used in our experiments to determine local changes of density in the shock pattern of an axisymmetric supersonic air jet. It is important to validate, in particular, the Gladstone Dale approximation (index of refraction close to one) in our experimental conditions and determine the uncertainty of our density measurements. In some cases, the index of refraction of the material is well known, but in others the density is measured and related to the displacement field. We acknowledge support from UNAM through DGAPA PAPIIT IN117712 and the Graduate Program in Mechanical Engineering.
Selected Translated Abstracts of Chinese-Language Climate Change Publications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cushman, R.M.; Burtis, M.D.
1999-05-01
This report contains English-translated abstracts of important Chinese-language literature concerning global climate change for the years 1995-1998. This body of literature includes the topics of adaptation, ancient climate change, climate variation, the East Asia monsoon, historical climate change, impacts, modeling, and radiation and trace-gas emissions. In addition to the biological citations and abstracts translated into English, this report presents the original citations and abstracts in Chinese. Author and title indexes are included to assist the reader in locating abstracts of particular interest.
Broad-band flared horn with low sidelobes. [applicable to cosmic background radiation measurement
NASA Technical Reports Server (NTRS)
Mather, J. C.
1981-01-01
A circular horn antenna flared like a trumpet is analyzed with the geometrical theory of diffraction and then tested experimentally. Sidelobes are found to be extremely low (-75 dB), in agreement with theory. Low sidelobe performance is predicted to be broad-band and to improve at higher frequencies. The full aperture of the tested horn is approximately 50 wavelengths. Suggestions for even better low sidelobe antennas are made. The applicability of this horn to the measurement of cosmic background radiation is noted.
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.
Children and Computers Abstracts.
ERIC Educational Resources Information Center
Rothenberg, Dianne, Ed.
1992-01-01
Abstracts of reports of eight research studies on computer uses in children's education are presented. Topics covered include (1) LOGO computer language; (2) computer graphics for art instruction; (3) animation; (4) problem solving; (5) children's use of symbols; (6) an evaluation of a Chapter 1 program involving children's computer use; (7) peer…
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…
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.
Abstract Imagery in Art Therapy: What Does It Mean?
ERIC Educational Resources Information Center
Hanes, Michael J.
1998-01-01
Explores some of the factors involving abstract imagery in the work of art-therapy patients and presents examples of abstract imagery produced by patients in an acute-patient psychiatric hospital. Examples illustrate that abstract imagery can serve not only a defensive purpose, but a progressive function as well. (Author/MKA)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zillich, Robert E., E-mail: robert.zillich@jku.at
2015-11-15
We construct an accurate imaginary time propagator for path integral Monte Carlo simulations for heterogeneous systems consisting of a mixture of atoms and molecules. We combine the pair density approximation, which is highly accurate but feasible only for the isotropic interactions between atoms, with the Takahashi–Imada approximation for general interactions. We present finite temperature simulations results for energy and structure of molecules–helium clusters X{sup 4}He{sub 20} (X=HCCH and LiH) which show a marked improvement over the Trotter approximation which has a 2nd-order time step bias. We show that the 4th-order corrections of the Takahashi–Imada approximation can also be applied perturbativelymore » to a 2nd-order simulation.« less
How to prepare and submit abstracts for scientific meetings
Japiassú, Andre Miguel
2013-01-01
The presentation of study results is a key step in scientific research, and submitting an abstract to a meeting is often the first form of public communication. Meeting abstracts have a defined structure that is similar to abstracts for scientific articles, with an introduction, the objective, methods, results and conclusions. However, abstracts for meetings are not presented as part of a full article and, therefore, must contain the necessary and most relevant data. In this article, we detail their structure and include tips to make them technically correct. PMID:23917970
How to prepare and submit abstracts for scientific meetings.
Japiassú, Andre Miguel
2013-01-01
The presentation of study results is a key step in scientific research, and submitting an abstract to a meeting is often the first form of public communication. Meeting abstracts have a defined structure that is similar to abstracts for scientific articles, with an introduction, the objective, methods, results and conclusions. However, abstracts for meetings are not presented as part of a full article and, therefore, must contain the necessary and most relevant data. In this article, we detail their structure and include tips to make them technically correct.
Optimal background matching camouflage.
Michalis, Constantine; Scott-Samuel, Nicholas E; Gibson, David P; Cuthill, Innes C
2017-07-12
Background matching is the most familiar and widespread camouflage strategy: avoiding detection by having a similar colour and pattern to the background. Optimizing background matching is straightforward in a homogeneous environment, or when the habitat has very distinct sub-types and there is divergent selection leading to polymorphism. However, most backgrounds have continuous variation in colour and texture, so what is the best solution? Not all samples of the background are likely to be equally inconspicuous, and laboratory experiments on birds and humans support this view. Theory suggests that the most probable background sample (in the statistical sense), at the size of the prey, would, on average, be the most cryptic. We present an analysis, based on realistic assumptions about low-level vision, that estimates the distribution of background colours and visual textures, and predicts the best camouflage. We present data from a field experiment that tests and supports our predictions, using artificial moth-like targets under bird predation. Additionally, we present analogous data for humans, under tightly controlled viewing conditions, searching for targets on a computer screen. These data show that, in the absence of predator learning, the best single camouflage pattern for heterogeneous backgrounds is the most probable sample. © 2017 The Authors.
The thermal background determines how the infrared and visual systems interact in pit vipers.
Chen, Qin; Liu, Yang; Brauth, Steven E; Fang, Guangzhan; Tang, Yezhong
2017-09-01
The thermal infrared (IR) sensing system of pit vipers is believed to complement vision and provide a substitute imaging system in dark environments. Theoretically, the IR system would best image a scene consisting of a homothermal target in cold surroundings as a bright spot on a dark background. To test this hypothesis, we evaluated how the pit viper ( Gloydius brevicaudus ) discriminates and strikes prey when the background temperature is either higher or lower than that of the prey (approximately 32-33°C) in different parts of the scene. Snakes were tested in a modified predation cage in which background temperatures were set to 26°C on one side and either 33 or 40°C on the opposite side when the eyes, the pit organs or neither sensory system was occluded. When the eyes were blocked, snakes preferred to strike prey on the 26°C side rather than on the 33°C side but showed no bias in the other conditions. Snakes showed no preference for 26 versus 40°C background temperature, although more missed strikes occurred when the eyes were occluded. The results thus revealed that the pit viper IR system can accomplish a 'brightness constancy' computation reflecting the difference between the target and background temperatures, much as the visual system compares the luminance of a figure and the background. Furthermore, the results show that the IR system performs less well for locating prey when the background is warmer than the target. © 2017. Published by The Company of Biologists Ltd.
Better approximation guarantees for job-shop scheduling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goldberg, L.A.; Paterson, M.; Srinivasan, A.
1997-06-01
Job-shop scheduling is a classical NP-hard problem. Shmoys, Stein & Wein presented the first polynomial-time approximation algorithm for this problem that has a good (polylogarithmic) approximation guarantee. We improve the approximation guarantee of their work, and present further improvements for some important NP-hard special cases of this problem (e.g., in the preemptive case where machines can suspend work on operations and later resume). We also present NC algorithms with improved approximation guarantees for some NP-hard special cases.
The imprint of proper motion of nonlinear structures on the cosmic microwave background
NASA Technical Reports Server (NTRS)
Tuluie, Robin; Laguna, Pablo
1995-01-01
We investigate the imprint of nonlinear matter condensations on the cosmic microwave background (CMB) in an Omega = 1, cold dark matter (CDM) model universe. Temperature anisotropies are obtained by numerically evolving matter inhomogeneities and CMB photons from the beginning of decoupling until the present epoch. The underlying density field produced by the inhomogeneities is followed from the linear, through the weakly clustered, into the fully nonlinear regime. We concentrate on CMB temperature distortions arising from variations in the gravitational potentials of nonlinear structures. We find two sources of temperature fluctuations produced by time-varying potentials: (1) anisotropies due to intrinsic changes in the gravitational potentials of the inhomogeneities and (2) anisotropies generated by the peculiar, bulk motion of the structures across the microwave sky. Both effects generate CMB anisotropies in the range of 10(exp -7) approximately less than or equal to (Delta T/T) approximately less than or equal to 10(exp -6) on scales of approximately 1 deg. For isolated structures, anisotropies due to proper motion exhibit a dipole-like signature in the CMB sky that in principle could yield information on the transverse velocity of the structures.
A "how-to" guide in preparing abstracts and poster presentations.
Boullata, Joseph I; Mancuso, Carissa E
2007-12-01
The preparation of an abstract or poster to share information from a project or case report with colleagues is a professional goal for many nutrition support practitioners. This paper provides an approach to help practitioners prepare an abstract for submission and subsequently a poster for presentation at a meeting. A nutrition support question that required collecting and evaluating information, or a unique patient case or case series, can serve as the focus of an abstract and subsequent poster. The professional meeting selected should be appropriate for the abstract topic, and the authors should closely adhere to the organization's abstract submission guidelines. The well-prepared abstract will then serve as the outline for the poster content; the visual aspect of the poster is also important to effectively communicate the information to colleagues at the meeting. Adequate time is required to prepare both the abstract and the poster in order to fittingly reflect the value of the information. Efforts in preparing the abstract will be worthwhile once the abstract has been accepted by reviewers for a poster session at the meeting. Likewise, the effort in preparing the poster in advance allows the presenter to enjoy the poster session and discuss the project with colleagues.
NASA Astrophysics Data System (ADS)
Arkhangelskaja, I. V.; Arkhangelskiy, A. I.
2016-02-01
The gamma-ray background physical origin for low altitude orbits defined by: diffuse cosmic gamma-emission, atmospheric gamma-rays, gamma-emission formed in interactions of charged particles (both prompt and activation) and transient events such as electrons precipitations and solar flares. The background conditions in the energy range from 0.1 MeV up to several MeV for low altitude orbits differ due to frequency of Earth Radiation Belts - ERBs (included South Atlantic Anomaly - SAA) passes and cosmic rays rigidity. The detectors and satellite constructive elements are activated by trapped in ERBs and moving along magnetic lines charged particles. In this case we propose simplified polynomial model separately for polar and equatorial orbits parts: background count rate temporal profile approximation by 4-5 order polynomials in equatorial regions, and linear approximations, parabolas or constants in polar caps. The polynomials’ coefficients supposed to be similar for identical spectral channels for each analyzed equatorial part taken into account normalization coefficients defined due to Kp-indexes study within period corresponding to calibration coefficients being approximately constants. The described model was successfully applied for the solar flares hard X-ray and gamma-ray emission characteristic studies by AVS-F apparatus data onboard CORONAS-F satellite.
Scatolini, Fabio; Alves, Cláudio Jorge Pinto
2016-01-01
ABSTRACT OBJECTIVE To perform a quantitative analysis of the background noise at Congonhas Airport surroundings based on large sampling and measurements with no interruption. METHODS Measuring sites were chosen from 62 and 72 DNL (day-night-level) noise contours, in urban sites compatible with residential use. Fifteen sites were monitored for at least 168 hours without interruption or seven consecutive days. Data compilation was based on cross-reference between noise measurements and air traffic control records, and results were validated by airport meteorological reports. Preliminary diagnoses were established using the standard NBR-13368. Background noise values were calculated based on the Sound Exposure Level (SEL). Statistic parameters were calculated in one-hour intervals. RESULTS Only four of the fifteen sites assessed presented aircraft operations as a clear cause for the noise annoyance. Even so, it is possible to detect background noise levels above regulation limits during periods of low airport activity or when it closes at night. CONCLUSIONS All the sites monitored showed background noise levels above regulation limits between 7:00 and 21:00. In the intervals between 6:00-6:59 and 21:00-22:59 the noise data, when analyzed with the current airport operational characteristics, still allow the development of additional mitigating measures. PMID:28099658
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…
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.
Linear Approximation SAR Azimuth Processing Study
NASA Technical Reports Server (NTRS)
Lindquist, R. B.; Masnaghetti, R. K.; Belland, E.; Hance, H. V.; Weis, W. G.
1979-01-01
A segmented linear approximation of the quadratic phase function that is used to focus the synthetic antenna of a SAR was studied. Ideal focusing, using a quadratic varying phase focusing function during the time radar target histories are gathered, requires a large number of complex multiplications. These can be largely eliminated by using linear approximation techniques. The result is a reduced processor size and chip count relative to ideally focussed processing and a correspondingly increased feasibility for spaceworthy implementation. A preliminary design and sizing for a spaceworthy linear approximation SAR azimuth processor meeting requirements similar to those of the SEASAT-A SAR was developed. The study resulted in a design with approximately 1500 IC's, 1.2 cubic feet of volume, and 350 watts of power for a single look, 4000 range cell azimuth processor with 25 meters resolution.
Land Application of Sewage Effluents and Sludges: Selected Abstracts.
ERIC Educational Resources Information Center
Environmental Protection Agency, Washington, DC. Office of Research and Development.
This report contains 568 selected abstracts concerned with the land application of sewage effluents and sludges. The abstracts are arranged in chronological groupings of ten-year periods from the l940's to the mid-l970's. The report also includes an author index and a subject matter index to facilitate reference to specific abstracts or narrower…
Orthopaedic Section Poster Presentations (Abstracts OPO1-OPO300).
2018-01-01
These abstracts are presented here as prepared by the authors. The accuracy and content of each abstract remain the responsibility of the authors. In the identification number above each abstract, OPO designates an Orthopaedic Section poster presentation. J Orthop Sports Phys Ther 2018;48(1):A67-A202. doi:10.2519/jospt.2018.48.1.A67.
Controlling Low-Rate Signal Path Microdischarge for an Ultra-Low-Background Proportional Counter
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mace, Emily K.; Aalseth, Craig E.; Bonicalzi, Ricco
2013-05-01
ABSTRACT Pacific Northwest National Laboratory (PNNL) has developed an ultra-low-background proportional counter (ULBPC) made of high purity copper. These detectors are part of an ultra-low-background counting system (ULBCS) in the newly constructed shallow underground laboratory at PNNL (at a depth of ~30 meters water-equivalent). To control backgrounds, the current preamplifier electronics are located outside the ULBCS shielding. Thus the signal from the detector travels through ~1 meter of cable and is potentially susceptible to high voltage microdischarge and other sources of electronic noise. Based on initial successful tests, commercial cables and connectors were used for this critical signal path. Subsequentmore » testing across different batches of commercial cables and connectors, however, showed unwanted (but still low) rates of microdischarge noise. To control this noise source, two approaches were pursued: first, to carefully validate cables, connectors, and other commercial components in this critical signal path, making modifications where necessary; second, to develop a custom low-noise, low-background preamplifier that can be integrated with the ULBPC and thus remove most commercial components from the critical signal path. This integrated preamplifier approach is based on the Amptek A250 low-noise charge-integrating preamplifier module. The initial microdischarge signals observed are presented and characterized according to the suspected source. Each of the approaches for mitigation is described, and the results from both are compared with each other and with the original performance seen with commercial cables and connectors.« less
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.
Acoustic invisibility cloaks of arbitrary shapes for complex background media
NASA Astrophysics Data System (ADS)
Zhu, Jian; Chen, Tianning; Liang, Qingxuan; Wang, Xiaopeng; Xiong, Jie; Jiang, Ping
2016-04-01
We report on the theoretical investigation of the acoustic cloaks working in complex background media in this paper. The constitutive parameters of arbitrary-shape cloaks are derived based on the transformation acoustic theory and coordinate transformation technique. The detailed analysis of boundaries conditions and potential applications of the cloaks are also presented in our work. To overcome the difficulty of achieving the materials with ideal parameters in nature, concentric alternating layered isotropic materials is adopted to approximate the required properties of the cloak. Theoretical design and excellent invisibility are demonstrated by numerical simulations. The inhomogeneous medium and arbitrary-shape acoustic cloaks grow closer to real application and may be a new hot spot in future.
On Nash-Equilibria of Approximation-Stable Games
NASA Astrophysics Data System (ADS)
Awasthi, Pranjal; Balcan, Maria-Florina; Blum, Avrim; Sheffet, Or; Vempala, Santosh
One reason for wanting to compute an (approximate) Nash equilibrium of a game is to predict how players will play. However, if the game has multiple equilibria that are far apart, or ɛ-equilibria that are far in variation distance from the true Nash equilibrium strategies, then this prediction may not be possible even in principle. Motivated by this consideration, in this paper we define the notion of games that are approximation stable, meaning that all ɛ-approximate equilibria are contained inside a small ball of radius Δ around a true equilibrium, and investigate a number of their properties. Many natural small games such as matching pennies and rock-paper-scissors are indeed approximation stable. We show furthermore there exist 2-player n-by-n approximation-stable games in which the Nash equilibrium and all approximate equilibria have support Ω(log n). On the other hand, we show all (ɛ,Δ) approximation-stable games must have an ɛ-equilibrium of support O(Δ^{2-o(1)}/ɛ2{log n}), yielding an immediate n^{O(Δ^{2-o(1)}/ɛ^2log n)}-time algorithm, improving over the bound of [11] for games satisfying this condition. We in addition give a polynomial-time algorithm for the case that Δ and ɛ are sufficiently close together. We also consider an inverse property, namely that all non-approximate equilibria are far from some true equilibrium, and give an efficient algorithm for games satisfying that condition.
DSH abstract: coverage of the world communicative disorders literature.
Seaton, W H; Williams, D M
1982-06-01
The percentage of journal articles covered by dsh Abstracts and the time it took these articles to appear as abstracts in this secondary publication were analyzed. Articles were obtained from nineteen communicative disorders journals every other year for the years from 1968 to 1976. Then the author index of dsh Abstracts was searched each year for up to five years following journal publication to determine whether each article was included in this abstracting service's coverage of the world literature. Of the 5548 articles included in the study, 3270 (59%) were covered by this abstracting service within a mean time of 9 months; however, time lag and coverage varied considerably for individual journals on a year by year basis. It was concluded that for historical searches and current awareness needs this secondary publication may not be meeting the information needs of communicative disorders specialists.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lynch, H.; Schwitters, R.F.; Toner, W.T.
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.
Use of an OSSE to Evaluate Background Error Covariances Estimated by the 'NMC Method'
NASA Technical Reports Server (NTRS)
Errico, Ronald M.; Prive, Nikki C.; Gu, Wei
2014-01-01
The NMC method has proven utility for prescribing approximate background-error covariances required by variational data assimilation systems. Here, untunedNMCmethod estimates are compared with explicitly determined error covariances produced within an OSSE context by exploiting availability of the true simulated states. Such a comparison provides insights into what kind of rescaling is required to render the NMC method estimates usable. It is shown that rescaling of variances and directional correlation lengths depends greatly on both pressure and latitude. In particular, some scaling coefficients appropriate in the Tropics are the reciprocal of those in the Extratropics. Also, the degree of dynamic balance is grossly overestimated by the NMC method. These results agree with previous examinations of the NMC method which used ensembles as an alternative for estimating background-error statistics.
Legendre-tau approximations for functional differential equations
NASA Technical Reports Server (NTRS)
Ito, K.; Teglas, R.
1986-01-01
The numerical approximation of solutions to linear retarded functional differential equations are considered using the so-called Legendre-tau method. The functional differential equation is first reformulated as a partial differential equation with a nonlocal boundary condition involving time-differentiation. The approximate solution is then represented as a truncated Legendre series with time-varying coefficients which satisfy a certain system of ordinary differential equations. The method is very easy to code and yields very accurate approximations. Convergence is established, various numerical examples are presented, and comparison between the latter and cubic spline approximation is made.
Legendre-Tau approximations for functional differential equations
NASA Technical Reports Server (NTRS)
Ito, K.; Teglas, R.
1983-01-01
The numerical approximation of solutions to linear functional differential equations are considered using the so called Legendre tau method. The functional differential equation is first reformulated as a partial differential equation with a nonlocal boundary condition involving time differentiation. The approximate solution is then represented as a truncated Legendre series with time varying coefficients which satisfy a certain system of ordinary differential equations. The method is very easy to code and yields very accurate approximations. Convergence is established, various numerical examples are presented, and comparison between the latter and cubic spline approximations is made.
Piecewise linear approximation for hereditary control problems
NASA Technical Reports Server (NTRS)
Propst, Georg
1987-01-01
Finite dimensional approximations are presented 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 has to be minimized subject to the controlled retarded system. It is shown that the approximate optimal feedback operators converge to the true ones both in case the cost integral ranges over a finite time interval as well as in the case it ranges over an infinite time interval. The arguments in the latter case rely on the fact that the piecewise linear approximations to stable systems are stable in a uniform sense. This feature is established using a vector-component stability criterion in the state space R(n) x L(2) and the favorable eigenvalue behavior of the piecewise linear approximations.
Approximation concepts for efficient structural synthesis
NASA Technical Reports Server (NTRS)
Schmit, L. A., Jr.; Miura, H.
1976-01-01
It is shown that efficient structural synthesis capabilities can be created by using approximation concepts to mesh finite element structural analysis methods with nonlinear mathematical programming techniques. The history of the application of mathematical programming techniques to structural design optimization problems is reviewed. Several rather general approximation concepts are described along with the technical foundations of the ACCESS 1 computer program, which implements several approximation concepts. A substantial collection of structural design problems involving truss and idealized wing structures is presented. It is concluded that since the basic ideas employed in creating the ACCESS 1 program are rather general, its successful development supports the contention that the introduction of approximation concepts will lead to the emergence of a new generation of practical and efficient, large scale, structural synthesis capabilities in which finite element analysis methods and mathematical programming algorithms will play a central role.
Pacifier Overuse and Conceptual Relations of Abstract and Emotional Concepts.
Barca, Laura; Mazzuca, Claudia; Borghi, Anna M
2017-01-01
This study explores the impact of the extensive use of an oral device since infancy (pacifier) on the acquisition of concrete, abstract, and emotional concepts. While recent evidence showed a negative relation between pacifier use and children's emotional competence (Niedenthal et al., 2012), the possible interaction between use of pacifier and processing of emotional and abstract language has not been investigated. According to recent theories, while all concepts are grounded in sensorimotor experience, abstract concepts activate linguistic and social information more than concrete ones. Specifically, the Words As Social Tools (WAT) proposal predicts that the simulation of their meaning leads to an activation of the mouth (Borghi and Binkofski, 2014; Borghi and Zarcone, 2016). Since the pacifier affects facial mimicry forcing mouth muscles into a static position, we hypothesize its possible interference on acquisition/consolidation of abstract emotional and abstract not-emotional concepts, which are mainly conveyed during social and linguistic interactions, than of concrete concepts. Fifty-nine first grade children, with a history of different frequency of pacifier use, provided oral definitions of the meaning of abstract not-emotional, abstract emotional, and concrete words. Main effect of concept type emerged, with higher accuracy in defining concrete and abstract emotional concepts with respect to abstract not-emotional concepts, independently from pacifier use. Accuracy in definitions was not influenced by the use of pacifier, but correspondence and hierarchical clustering analyses suggest that the use of pacifier differently modulates the conceptual relations elicited by abstract emotional and abstract not-emotional. While the majority of the children produced a similar pattern of conceptual relations, analyses on the few (6) children who overused the pacifier (for more than 3 years) showed that they tend to distinguish less clearly between concrete and
Pacifier Overuse and Conceptual Relations of Abstract and Emotional Concepts
Barca, Laura; Mazzuca, Claudia; Borghi, Anna M.
2017-01-01
This study explores the impact of the extensive use of an oral device since infancy (pacifier) on the acquisition of concrete, abstract, and emotional concepts. While recent evidence showed a negative relation between pacifier use and children's emotional competence (Niedenthal et al., 2012), the possible interaction between use of pacifier and processing of emotional and abstract language has not been investigated. According to recent theories, while all concepts are grounded in sensorimotor experience, abstract concepts activate linguistic and social information more than concrete ones. Specifically, the Words As Social Tools (WAT) proposal predicts that the simulation of their meaning leads to an activation of the mouth (Borghi and Binkofski, 2014; Borghi and Zarcone, 2016). Since the pacifier affects facial mimicry forcing mouth muscles into a static position, we hypothesize its possible interference on acquisition/consolidation of abstract emotional and abstract not-emotional concepts, which are mainly conveyed during social and linguistic interactions, than of concrete concepts. Fifty-nine first grade children, with a history of different frequency of pacifier use, provided oral definitions of the meaning of abstract not-emotional, abstract emotional, and concrete words. Main effect of concept type emerged, with higher accuracy in defining concrete and abstract emotional concepts with respect to abstract not-emotional concepts, independently from pacifier use. Accuracy in definitions was not influenced by the use of pacifier, but correspondence and hierarchical clustering analyses suggest that the use of pacifier differently modulates the conceptual relations elicited by abstract emotional and abstract not-emotional. While the majority of the children produced a similar pattern of conceptual relations, analyses on the few (6) children who overused the pacifier (for more than 3 years) showed that they tend to distinguish less clearly between concrete and
Possibilities of identifying cyber attack in noisy space of n-dimensional abstract system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jašek, Roman; Dvořák, Jiří; Janková, Martina
This article briefly mentions some selected options of current concept for identifying cyber attacks from the perspective of the new cyberspace of real system. In the cyberspace, there is defined n-dimensional abstract system containing elements of the spatial arrangement of partial system elements such as micro-environment of cyber systems surrounded by other suitably arranged corresponding noise space. This space is also gradually supplemented by a new image of dynamic processes in a discreet environment, and corresponding again to n-dimensional expression of time space defining existence and also the prediction for expected cyber attacksin the noise space. Noises are seen heremore » as useful and necessary for modern information and communication technologies (e.g. in processes of applied cryptography in ICT) and then the so-called useless noises designed for initial (necessary) filtering of this highly aggressive environment and in future expectedly offensive background in cyber war (e.g. the destruction of unmanned means of an electromagnetic pulse, or for destruction of new safety barriers created on principles of electrostatic field or on other principles of modern physics, etc.). The key to these new options is the expression of abstract systems based on the models of microelements of cyber systems and their hierarchical concept in structure of n-dimensional system in given cyberspace. The aim of this article is to highlight the possible systemic expression of cyberspace of abstract system and possible identification in time-spatial expression of real environment (on microelements of cyber systems and their surroundings with noise characteristics and time dimension in dynamic of microelements’ own time and externaltime defined by real environment). The article was based on a partial task of faculty specific research.« less
3D Visualizations of Abstract DataSets
2010-08-01
contrasts no shadows, drop shadows and drop lines. 15. SUBJECT TERMS 3D displays, 2.5D displays, abstract network visualizations, depth perception , human...altitude perception in airspace management and airspace route planning—simulated reality visualizations that employ altitude and heading as well as...cues employed by display designers for depicting real-world scenes on a flat surface can be applied to create a perception of depth for abstract
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…
Brain network response underlying decisions about abstract reinforcers.
Mills-Finnerty, Colleen; Hanson, Catherine; Hanson, Stephen Jose
2014-12-01
Decision making studies typically use tasks that involve concrete action-outcome contingencies, in which subjects do something and get something. No studies have addressed decision making involving abstract reinforcers, where there are no action-outcome contingencies and choices are entirely hypothetical. The present study examines these kinds of choices, as well as whether the same biases that exist for concrete reinforcer decisions, specifically framing effects, also apply during abstract reinforcer decisions. We use both General Linear Model as well as Bayes network connectivity analysis using the Independent Multi-sample Greedy Equivalence Search (IMaGES) algorithm to examine network response underlying choices for abstract reinforcers under positive and negative framing. We find for the first time that abstract reinforcer decisions activate the same network of brain regions as concrete reinforcer decisions, including the striatum, insula, anterior cingulate, and VMPFC, results that are further supported via comparison to a meta-analysis of decision making studies. Positive and negative framing activated different parts of this network, with stronger activation in VMPFC during negative framing and in DLPFC during positive, suggesting different decision making pathways depending on frame. These results were further clarified using connectivity analysis, which revealed stronger connections between anterior cingulate, insula, and accumbens during negative framing compared to positive. Taken together, these results suggest that not only do abstract reinforcer decisions rely on the same brain substrates as concrete reinforcers, but that the response underlying framing effects on abstract reinforcers also resemble those for concrete reinforcers, specifically increased limbic system connectivity during negative frames. Copyright © 2014 Elsevier Inc. All rights reserved.
Characterizing the peak in the cosmic microwave background angular power spectrum
Knox; Page
2000-08-14
A peak has been unambiguously detected in the cosmic microwave background angular spectrum. Here we characterize its properties with fits to phenomenological models. We find that the TOCO and BOOM/NA data determine the peak location to be in the range 175-243 and 151-259, respectively (at 95% confidence) and determine the peak amplitude to be between approximately 70 and 90 &mgr;K. The peak shape is consistent with inflation-inspired flat, cold dark matter plus cosmological constant models of structure formation with adiabatic, nearly scale invariant initial conditions. It is inconsistent with open models and presents a great challenge to defect models.
NASA Astrophysics Data System (ADS)
Lamberts, T.; Fedoseev, G.; Kästner, J.; Ioppolo, S.; Linnartz, H.
2017-03-01
We present a combined experimental and theoretical study focussing on the quantum tunneling of atoms in the reaction between CH4 and OH. The importance of this reaction pathway is derived by investigating isotope substituted analogs. Quantitative reaction rates needed for astrochemical models at low temperature are currently unavailable both in the solid state and in the gas phase. Here, we study tunneling effects upon hydrogen abstraction in CH4 + OH by focusing on two reactions: CH4 + OD → CH3 + HDO and CD4 + OH → CD3 + HDO. The experimental study shows that the solid-state reaction rate RCH4 + OD is higher than RCD4 + OH at 15 K. Experimental results are accompanied by calculations of the corresponding unimolecular and bimolecular reaction rate constants using instanton theory taking into account surface effects. For the work presented here, the unimolecular reactions are particularly interesting as these provide insight into reactions following a Langmuir-Hinshelwood process. The resulting ratio of the rate constants shows that the H abstraction (kCH4 + OD) is approximately ten times faster than D-abstraction (kCD4 + OH) at 65 K. We conclude that tunneling is involved at low temperatures in the abstraction reactions studied here. The unimolecular rate constants can be used by the modeling community as a first approach to describe OH-mediated abstraction reactions in the solid phase. For this reason we provide fits of our calculated rate constants that allow the inclusion of these reactions in models in a straightforward fashion.
Approximations of e and ?: An Exploration
ERIC Educational Resources Information Center
Brown, Philip R.
2017-01-01
Fractional approximations of e and p are discovered by searching for repetitions or partial repetitions of digit strings in their expansions in different number bases. The discovery of such fractional approximations is suggested for students and teachers as an entry point into mathematics research.
Improved Discrete Approximation of Laplacian of Gaussian
NASA Technical Reports Server (NTRS)
Shuler, Robert L., Jr.
2004-01-01
An improved method of computing a discrete approximation of the Laplacian of a Gaussian convolution of an image has been devised. The primary advantage of the method is that without substantially degrading the accuracy of the end result, it reduces the amount of information that must be processed and thus reduces the amount of circuitry needed to perform the Laplacian-of- Gaussian (LOG) operation. Some background information is necessary to place the method in context. The method is intended for application to the LOG part of a process of real-time digital filtering of digitized video data that represent brightnesses in pixels in a square array. The particular filtering process of interest is one that converts pixel brightnesses to binary form, thereby reducing the amount of information that must be performed in subsequent correlation processing (e.g., correlations between images in a stereoscopic pair for determining distances or correlations between successive frames of the same image for detecting motions). The Laplacian is often included in the filtering process because it emphasizes edges and textures, while the Gaussian is often included because it smooths out noise that might not be consistent between left and right images or between successive frames of the same image.
Topics in Multivariate Approximation Theory.
1982-05-01
once that a continuous function f can be approximated from Sa :o span (N3 )B63 to within *(f, 131 ), with 13 t- sup3 e3 dian PS The simple approximation...N(C) 3- U P s P3AC 0 0 ) . Then, as in Lebesgue’s inequality, we could conclude that f - Qf - f-p - Q(f-p) , for all p e k k therefore I(f-0f) JCI 4 I
International symposium on erosion and landscape evolution abstracts
USDA-ARS?s Scientific Manuscript database
This book contains all of the extended abstracts from the ASABE specialty conference, the International Symposium on Erosion and Landscape Evolution (ISELE), held September 18-21, 2011 at the Hilton Anchorage Hotel in Anchorage, Alaska. Three extended abstracts from the meeting keynote speakers as ...
Abstracts of Research, July 1973 through June 1974.
ERIC Educational Resources Information Center
Ohio State Univ., Columbus. Computer and Information Science Research Center.
Abstracts of research papers in the fields of computer and information science are given; 72 papers are abstracted in the areas of information storage and retrieval, information processing, linguistic analysis, artificial intelligence, mathematical techniques, systems programing, and computer networks. In addition, the Ohio State University…
Odors and Air Pollution: A Bibliography with Abstracts.
ERIC Educational Resources Information Center
Environmental Protection Agency, Research Triangle Park, NC. Office of Air Programs.
The annotated bibliography presents a compilation of abstracts which deal with odors as they relate to air pollution. The abstracts are arranged within the following categories: Emission sources; Control methods; Measurement methods; Air quality measurements; Atmospheric interaction; Basic science and technology; Effects-human health;…
Efficiency of the human observer detecting random signals in random backgrounds
Park, Subok; Clarkson, Eric; Kupinski, Matthew A.; Barrett, Harrison H.
2008-01-01
The efficiencies of the human observer and the channelized-Hotelling observer relative to the ideal observer for signal-detection tasks are discussed. Both signal-known-exactly (SKE) tasks and signal-known-statistically (SKS) tasks are considered. Signal location is uncertain for the SKS tasks, and lumpy backgrounds are used for background uncertainty in both cases. Markov chain Monte Carlo methods are employed to determine ideal-observer performance on the detection tasks. Psychophysical studies are conducted to compute human-observer performance on the same tasks. Efficiency is computed as the squared ratio of the detectabilities of the observer of interest to the ideal observer. Human efficiencies are approximately 2.1% and 24%, respectively, for the SKE and SKS tasks. The results imply that human observers are not affected as much as the ideal observer by signal-location uncertainty even though the ideal observer outperforms the human observer for both tasks. Three different simplified pinhole imaging systems are simulated, and the humans and the model observers rank the systems in the same order for both the SKE and the SKS tasks. PMID:15669610
Differential emotional processing in concrete and abstract words.
Yao, Bo; Keitel, Anne; Bruce, Gillian; Scott, Graham G; O'Donnell, Patrick J; Sereno, Sara C
2018-02-12
Emotion (positive and negative) words are typically recognized faster than neutral words. Recent research suggests that emotional valence, while often treated as a unitary semantic property, may be differentially represented in concrete and abstract words. Studies that have explicitly examined the interaction of emotion and concreteness, however, have demonstrated inconsistent patterns of results. Moreover, these findings may be limited as certain key lexical variables (e.g., familiarity, age of acquisition) were not taken into account. We investigated the emotion-concreteness interaction in a large-scale, highly controlled lexical decision experiment. A 3 (Emotion: negative, neutral, positive) × 2 (Concreteness: abstract, concrete) design was used, with 45 items per condition and 127 participants. We found a significant interaction between emotion and concreteness. Although positive and negative valenced words were recognized faster than neutral words, this emotion advantage was significantly larger in concrete than in abstract words. We explored potential contributions of participant alexithymia level and item imageability to this interactive pattern. We found that only word imageability significantly modulated the emotion-concreteness interaction. While both concrete and abstract emotion words are advantageously processed relative to comparable neutral words, the mechanisms of this facilitation are paradoxically more dependent on imageability in abstract words. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Editors' Introduction: Abstract Concepts: Structure, Processing, and Modeling.
Bolognesi, Marianna; Steen, Gerard
2018-06-22
Our ability to deal with abstract concepts is one of the most intriguing faculties of human cognition. Still, we know little about how such concepts are formed, processed, and represented in mind. For example, because abstract concepts do not designate referents that can be experienced through our body, the role of perceptual experiences in shaping their content remains controversial. Current theories suggest a variety of alternative explanations to the question of "how abstract concepts are represented in the human mind." These views pinpoint specific streams of semantic information that would play a prominent role in shaping the content of abstract concepts, such as situation-based information (e.g., Barsalou & Wiemer-Hastings, ), affective information (Kousta, Vigliocco, Vinson, Andrews, & Del Campo, ), and linguistic information (Louwerse, ). Rarely, these theoretical views are directly compared. In this special issue, current views are presented in their most recent and advanced form, and directly compared and discussed in a debate, which is reported at the end of each article. As a result, new exciting questions and challenges arise. These questions and challenges, reported in this introductory article, can arguably pave the way to new empirical studies and theoretical developments on the nature of abstract concepts. © 2018 Cognitive Science Society, Inc.
Microarray image analysis: background estimation using quantile and morphological filters.
Bengtsson, Anders; Bengtsson, Henrik
2006-02-28
In a microarray experiment the difference in expression between genes on the same slide is up to 103 fold or more. At low expression, even a small error in the estimate will have great influence on the final test and reference ratios. In addition to the true spot intensity the scanned signal consists of different kinds of noise referred to as background. In order to assess the true spot intensity background must be subtracted. The standard approach to estimate background intensities is to assume they are equal to the intensity levels between spots. In the literature, morphological opening is suggested to be one of the best methods for estimating background this way. This paper examines fundamental properties of rank and quantile filters, which include morphological filters at the extremes, with focus on their ability to estimate between-spot intensity levels. The bias and variance of these filter estimates are driven by the number of background pixels used and their distributions. A new rank-filter algorithm is implemented and compared to methods available in Spot by CSIRO and GenePix Pro by Axon Instruments. Spot's morphological opening has a mean bias between -47 and -248 compared to a bias between 2 and -2 for the rank filter and the variability of the morphological opening estimate is 3 times higher than for the rank filter. The mean bias of Spot's second method, morph.close.open, is between -5 and -16 and the variability is approximately the same as for morphological opening. The variability of GenePix Pro's region-based estimate is more than ten times higher than the variability of the rank-filter estimate and with slightly more bias. The large variability is because the size of the background window changes with spot size. To overcome this, a non-adaptive region-based method is implemented. Its bias and variability are comparable to that of the rank filter. The performance of more advanced rank filters is equal to the best region-based methods. However, in
Approximation methods for combined thermal/structural design
NASA Technical Reports Server (NTRS)
Haftka, R. T.; Shore, C. P.
1979-01-01
Two approximation concepts for combined thermal/structural design are evaluated. The first concept is an approximate thermal analysis based on the first derivatives of structural temperatures with respect to design variables. Two commonly used first-order Taylor series expansions are examined. The direct and reciprocal expansions are special members of a general family of approximations, and for some conditions other members of that family of approximations are more accurate. Several examples are used to compare the accuracy of the different expansions. The second approximation concept is the use of critical time points for combined thermal and stress analyses of structures with transient loading conditions. Significant time savings are realized by identifying critical time points and performing the stress analysis for those points only. The design of an insulated panel which is exposed to transient heating conditions is discussed.
The Paradox of Abstraction: Precision Versus Concreteness.
Iliev, Rumen; Axelrod, Robert
2017-06-01
We introduce a novel measure of abstractness based on the amount of information of a concept computed from its position in a semantic taxonomy. We refer to this measure as precision. We propose two alternative ways to measure precision, one based on the path length from a concept to the root of the taxonomic tree, and another one based on the number of direct and indirect descendants. Since more information implies greater processing load, we hypothesize that nouns higher in precision will have a processing disadvantage in a lexical decision task. We contrast precision to concreteness, a common measure of abstractness based on the proportion of sensory-based information associated with a concept. Since concreteness facilitates cognitive processing, we predict that while both concreteness and precision are measures of abstractness, they will have opposite effects on performance. In two studies we found empirical support for our hypothesis. Precision and concreteness had opposite effects on latency and accuracy in a lexical decision task, and these opposite effects were observable while controlling for word length, word frequency, affective content and semantic diversity. Our results support the view that concepts organization includes amodal semantic structures which are independent of sensory information. They also suggest that we should distinguish between sensory-based and amount-of-information-based abstractness.
Abstract Algebra for Teachers: An Evaluative Case Study
ERIC Educational Resources Information Center
Hoffman, Andrew Joseph
2017-01-01
This manuscript describes the study of an abstract algebra course for preservice secondary mathematics teachers (PSMTs). Often, courses in abstract algebra have not been viewed as productive, beneficial learning experiences for future teachers, both by researchers and PSMTs themselves. This despite calls for increased content knowledge for…
NASA Technical Reports Server (NTRS)
Schmidt, A. F. (Editor)
1972-01-01
Selected information is presented from an assemblage of reports and publications on heat transfer and fluid dynamics with direct applicability to oxygen systems. For each document cited, an abstract has been prepared together with key words and a listing of most important references found in the document. Additionally, an author index, a subject index, and a key word index have been provided to simplify the retrieval of specific information from this work. In each subject area - e.g., boiling heat transfer - the individual citations are listed alphabetically by first author, with review papers dually noted under the appropriate subject category and under review papers. Of the documents reviewed and evaluated for inclusion in this publication, coverage of existing information directly concerned with oxygen was given primary emphasis. However, work not specifically oxygen-designated but considered applicable to oxygen by the reviewer e.g., a two-phase friction factor correlation derived from nitrogen experiments is occasionally given where no actual oxygen data exist, as an aid to the reader. Approximately 130 abstracts are listed.
Intuitive reasoning about abstract and familiar physics problems
NASA Technical Reports Server (NTRS)
Kaiser, Mary Kister; Jonides, John; Alexander, Joanne
1986-01-01
Previous research has demonstrated that many people have misconceptions about basic properties of motion. Two experiments examined whether people are more likely to produce dynamically correct predictions about basic motion problems involving situations with which they are familiar, and whether solving such problems enhances performance on a subsequent abstract problem. In experiment 1, college students were asked to predict the trajectories of objects exiting a curved tube. Subjects were more accurate on the familiar version of the problem, and there was no evidence of transfer to the abstract problem. In experiment 2, two familiar problems were provided in an attempt to enhance subjects' tendency to extract the general structure of the problems. Once again, they gave more correct responses to the familiar problems but failed to generalize to the abstract problem. Formal physics training was associated with correct predictions for the abstract problem but was unrelated to performance on the familiar problems.
Grasping the invisible: semantic processing of abstract words.
Zdrazilova, Lenka; Pexman, Penny M
2013-12-01
The problem of how abstract word meanings are represented has been a challenging one. In the present study, we extended the semantic richness approach (e.g., Yap, Tan, Pexman, & Hargreaves in Psychonomic Bulletin & Review 18:742-750, 2011) to abstract words, examining the effects of six semantic richness variables on lexical-semantic processing for 207 abstract nouns. The candidate richness dimensions were context availability (CA), sensory experience rating (SER), valence, arousal, semantic neighborhood (SN), and number of associates (NoA). The behavioral tasks were lexical decision (LDT) and semantic categorization (SCT). Our results showed that the semantic richness variables were significantly related to both LDT and SCT latencies, even after lexical and orthographic factors were controlled. The patterns of richness effects varied across tasks, with CA effects in the LDT, and SER and valence effects in the SCT. These results provide new insight into how abstract meanings may be grounded, and are consistent with a dynamic, multidimensional framework for semantic processing.
High-efficiency and low-background multi-segmented proportional gas counter for β-decay spectroscopy
NASA Astrophysics Data System (ADS)
Mukai, M.; Hirayama, Y.; Watanabe, Y. X.; Schury, P.; Jung, H. S.; Ahmed, M.; Haba, H.; Ishiyama, H.; Jeong, S. C.; Kakiguchi, Y.; Kimura, S.; Moon, J. Y.; Oyaizu, M.; Ozawa, A.; Park, J. H.; Ueno, H.; Wada, M.; Miyatake, H.
2018-03-01
A multi-segmented proportional gas counter (MSPGC) with high detection efficiency and low-background event rate has been developed for β-decay spectroscopy. The MSPGC consists of two cylindrically aligned layers of 16 counters (32 counters in total). Each counter has a long active length and small trapezoidal cross-section, and the total solid angle of the 32 counters is 80% of 4 π. β-rays are distinguished from the background events including cosmic-rays by analyzing the hit patterns of independent counters. The deduced intrinsic detection efficiency of each counter was almost 100%. The measured background event rate was 0.11 counts per second using the combination of veto counters for cosmic-rays and lead block shields for background γ-rays. The MSPGC was applied to measure the β-decay half-lives of 198Ir and 199mPt. The evaluated half-lives of T1/2 = 9 . 8(7) s and 12.4(7) s for 198Ir and 199mPt, respectively, were in agreement with previously reported values. The estimated absolute detection efficiency of the MSPGC from GEANT4 simulations was consistent with the evaluated efficiency from the analysis of the β- γ spectroscopy of 199Pt, saturating at approximately 60% for Qβ > 4 MeV.
Abstracts of ARI Research Publications, FY 1979
1980-11-01
Technical Report 483 ABSTRACTS OF ARI RESEARCH PUBLICATIONS FY 1979 -- C:) U. S . ArmyL.) LAa Research Institute for the Behavioral and Social...U. S . ARMY RESEARCH INSTITUTE FOR THE BEHAVIORAL AND SOCIAL SCIENCES A Field Operating Agency under the Jurisdiction of the Deputy Chief of Staff...PIEIT’S ATALOG NUMBER Technical Report 483 l L~,2 y. (-P- NUZE 4. TITLE (nd Subtfti.) S . TYPE OF REPORT & PERIOD COVERED ABSTRACTS OF ARI RESEARCH
A result about scale transformation families in approximation
NASA Astrophysics Data System (ADS)
Apprato, Dominique; Gout, Christian
2000-06-01
Scale transformations are common in approximation. In surface approximation from rapidly varying data, one wants to suppress, or at least dampen the oscillations of the approximation near steep gradients implied by the data. In that case, scale transformations can be used to give some control over overshoot when the surface has large variations of its gradient. Conversely, in image analysis, scale transformations are used in preprocessing to enhance some features present on the image or to increase jumps of grey levels before segmentation of the image. In this paper, we establish the convergence of an approximation method which allows some control over the behavior of the approximation. More precisely, we study the convergence of an approximation from a data set of , while using scale transformations on the values before and after classical approximation. In addition, the construction of scale transformations is also given. The algorithm is presented with some numerical examples.
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…
Honors Dissertation Abstracts: A Bounded Qualitative Meta-Study
ERIC Educational Resources Information Center
Holman, Debra K.; Banning, James H.
2012-01-01
A potential source of useful information about undergraduate honors education can be found in doctoral dissertation abstracts that focus on honors. Debra Holman and James Banning of Colorado State University sought to explore this resource by undertaking a bounded qualitative meta-study of such abstracts using document analysis. Three…
Approximations to camera sensor noise
NASA Astrophysics Data System (ADS)
Jin, Xiaodan; Hirakawa, Keigo
2013-02-01
Noise is present in all image sensor data. Poisson distribution is said to model the stochastic nature of the photon arrival process, while it is common to approximate readout/thermal noise by additive white Gaussian noise (AWGN). Other sources of signal-dependent noise such as Fano and quantization also contribute to the overall noise profile. Question remains, however, about how best to model the combined sensor noise. Though additive Gaussian noise with signal-dependent noise variance (SD-AWGN) and Poisson corruption are two widely used models to approximate the actual sensor noise distribution, the justification given to these types of models are based on limited evidence. The goal of this paper is to provide a more comprehensive characterization of random noise. We concluded by presenting concrete evidence that Poisson model is a better approximation to real camera model than SD-AWGN. We suggest further modification to Poisson that may improve the noise model.
Approximate techniques of structural reanalysis
NASA Technical Reports Server (NTRS)
Noor, A. K.; Lowder, H. E.
1974-01-01
A study is made of two approximate techniques for structural reanalysis. These include Taylor series expansions for response variables in terms of design variables and the reduced-basis method. In addition, modifications to these techniques are proposed to overcome some of their major drawbacks. The modifications include a rational approach to the selection of the reduced-basis vectors and the use of Taylor series approximation in an iterative process. For the reduced basis a normalized set of vectors is chosen which consists of the original analyzed design and the first-order sensitivity analysis vectors. The use of the Taylor series approximation as a first (initial) estimate in an iterative process, can lead to significant improvements in accuracy, even with one iteration cycle. Therefore, the range of applicability of the reanalysis technique can be extended. Numerical examples are presented which demonstrate the gain in accuracy obtained by using the proposed modification techniques, for a wide range of variations in the design variables.
NASA Astrophysics Data System (ADS)
Aleksandrov, A. P.; Berezovoj, A. N.; Gal'Per, A. M.; Grachev, V. M.; Dmitrenko, V. V.; Kirillov-Ugryumov, V. G.; Lebedev, V. V.; Lyakhov, V. A.; Moiseev, A. A.; Ulin, S. E.; Shchvets, N. I.
1984-11-01
Coding collimators are used to improve the angular resolution of gamma-ray telescopes at energies above 50 MeV. However, the interaction of cosmic rays with the collimator material can lead to the appearance of a gramma-ray background flux which can have a deleterious effect on measurement efficiency. An experiment was performed on the Salyut-6-Soyuz spacecraft system with the Elena-F small-scale gamma-ray telescope in order to measure the magnitude of this background. It is shown that, even at a zenith angle of approximately zero degrees (the angle at which the gamma-ray observations are made), the coding collimator has only an insignificant effect on the background conditions.
Generating effective project scheduling heuristics by abstraction and reconstitution
NASA Technical Reports Server (NTRS)
Janakiraman, Bhaskar; Prieditis, Armand
1992-01-01
A project scheduling problem consists of a finite set of jobs, each with fixed integer duration, requiring one or more resources such as personnel or equipment, and each subject to a set of precedence relations, which specify allowable job orderings, and a set of mutual exclusion relations, which specify jobs that cannot overlap. No job can be interrupted once started. The objective is to minimize project duration. This objective arises in nearly every large construction project--from software to hardware to buildings. Because such project scheduling problems are NP-hard, they are typically solved by branch-and-bound algorithms. In these algorithms, lower-bound duration estimates (admissible heuristics) are used to improve efficiency. One way to obtain an admissible heuristic is to remove (abstract) all resources and mutual exclusion constraints and then obtain the minimal project duration for the abstracted problem; this minimal duration is the admissible heuristic. Although such abstracted problems can be solved efficiently, they yield inaccurate admissible heuristics precisely because those constraints that are central to solving the original problem are abstracted. This paper describes a method to reconstitute the abstracted constraints back into the solution to the abstracted problem while maintaining efficiency, thereby generating better admissible heuristics. Our results suggest that reconstitution can make good admissible heuristics even better.
Enhancements to the NASA Astrophysics Science Information and Abstract Service
NASA Astrophysics Data System (ADS)
Kurtz, M. J.; Eichhorn, G.; Accomazzi, A.; Grant, C. S.; Murray, S. S.
1995-05-01
The NASA Astrophysics Data System Astrophysics Science Information and Abstract Service, the extension of the ADS Abstract Service continues rapidly to expand in both use and capabilities. Each month the service is used by about 4,000 different people, and returns about 1,000,000 pieces of bibliographic information. Among the recent additions to the system are: 1. Whole Text Access. In addition to the ApJ Letters we now have whole text for the ApJ on-line, soon we will have AJ and Rev. Mexicana. Discussions with other publishers are in progress. 2. Space Instrumentation Database. We now provide a second abstract service, covering papers related to space instruments. This is larger than the astronomy and astrophysics database in terms of total abstracts. 3. Reference Books and Historical Journals. We have begun putting the SAO Annals and the HCO Annals on-line. We have put the Handbook of Space Astronomy and Astrophysics by M.V. Zombeck (Cambridge U.P.) on-line. 4. Author Abstracts. We can now include original abstracts in addition to those we get from the NASA STI Abstracts Database. We have included abstracts for A&A in collaboration with the CDS in Strasbourg, and are collaborating with the AAS and the ASP on others. We invite publishers and editors of journals and conference proceedings to include their original abstracts in our service; send inquiries via e-mail to ads@cfa.harvard.edu. 5. Author Notes. We now accept notes and comments from authors of articles in our database. These are arbitrary html files and may contain pointers to other WWW documents, they are listed along with the abstracts, whole text, and data available in the index listing for every reference. The ASIAS is available at: http://adswww.harvard.edu/
The evolution of voids in the adhesion approximation
NASA Astrophysics Data System (ADS)
Sahni, Varun; Sathyaprakah, B. S.; Shandarin, Sergei F.
1994-08-01
We apply the adhesion approximation to study the formation and evolution of voids in the universe. Our simulations-carried out using 1283 particles in a cubical box with side 128 Mpc-indicate that the void spectrum evolves with time and that the mean void size in the standard Cosmic Background Explorer Satellite (COBE)-normalized cold dark matter (CDM) model with H50 = 1 scals approximately as bar D(z) = bar Dzero/(1+2)1/2, where bar Dzero approximately = 10.5 Mpc. Interestingly, we find a strong correlation between the sizes of voids and the value of the primordial gravitational potential at void centers. This observation could in principle, pave the way toward reconstructing the form of the primordial potential from a knowledge of the observed void spectrum. Studying the void spectrum at different cosmological epochs, for spectra with a built in k-space cutoff we find that the number of voids in a representative volume evolves with time. The mean number of voids first increases until a maximum value is reached (indicating that the formation of cellular structure is complete), and then begins to decrease as clumps and filaments erge leading to hierarchical clustering and the subsequent elimination of small voids. The cosmological epoch characterizing the completion of cellular structure occurs when the length scale going nonlinear approaches the mean distance between peaks of the gravitaional potential. A central result of this paper is that voids can be populated by substructure such as mini-sheets and filaments, which run through voids. The number of such mini-pancakes that pass through a given void can be measured by the genus characteristic of an individual void which is an indicator of the topology of a given void in intial (Lagrangian) space. Large voids have on an average a larger measure than smaller voids indicating more substructure within larger voids relative to smaller ones. We find that the topology of individual voids is strongly epoch dependent
NASA Astrophysics Data System (ADS)
Carrillo-Rivera, J. J.; Cardona, A.; Edmunds, W. M.
2002-04-01
Significant amounts of fluoride are found in the abstracted groundwater of San Luis Potosí. This groundwater withdrawal induces a cold, low-fluoride flow as well as deeper thermal fluoride-rich flow in various proportions. Flow mixing takes place depending on the abstraction regime, local hydrogeology, and borehole construction design and operation. Fluoride concentrations (≈3.7 mg l -1) could become higher still, in time and space, if the input of regional fluoride-rich water to the abstraction boreholes is enhanced. It is suggested that by controlling the abstraction well-head water temperature at 28-30 °C, a pumped water mixture with a fluoride content close to the maximum drinking water standard of 1.5 mg l -1 will be produced. Further, new boreholes and those already operating could take advantage of fluoride solubility controls to reduce the F concentration in the abstracted water by considering lithology and borehole construction design in order to regulate groundwater flow conditions.
Approximate Bayesian evaluations of measurement uncertainty
NASA Astrophysics Data System (ADS)
Possolo, Antonio; Bodnar, Olha
2018-04-01
The Guide to the Expression of Uncertainty in Measurement (GUM) includes formulas that produce an estimate of a scalar output quantity that is a function of several input quantities, and an approximate evaluation of the associated standard uncertainty. This contribution presents approximate, Bayesian counterparts of those formulas for the case where the output quantity is a parameter of the joint probability distribution of the input quantities, also taking into account any information about the value of the output quantity available prior to measurement expressed in the form of a probability distribution on the set of possible values for the measurand. The approximate Bayesian estimates and uncertainty evaluations that we present have a long history and illustrious pedigree, and provide sufficiently accurate approximations in many applications, yet are very easy to implement in practice. Differently from exact Bayesian estimates, which involve either (analytical or numerical) integrations, or Markov Chain Monte Carlo sampling, the approximations that we describe involve only numerical optimization and simple algebra. Therefore, they make Bayesian methods widely accessible to metrologists. We illustrate the application of the proposed techniques in several instances of measurement: isotopic ratio of silver in a commercial silver nitrate; odds of cryptosporidiosis in AIDS patients; height of a manometer column; mass fraction of chromium in a reference material; and potential-difference in a Zener voltage standard.
Mercury and Air Pollution: A Bibliography With Abstracts.
ERIC Educational Resources Information Center
Environmental Protection Agency, Research Triangle Park, NC. Office of Air Programs.
The Air Pollution Technical Information Center (APTIC) of the Office of Air Programs has selected and compiled this bibliography of abstracts on mercury and air pollution. The abstracted documents are considered representative of available literature, although not all-inclusive. They are grouped into eleven categories: (1) Emission Sources, (2)…
Innovation Abstracts: Volume XII, Numbers 1-30, 1990.
ERIC Educational Resources Information Center
Roueche, Susanne D., Ed.
1990-01-01
This series of one- to two-page abstracts highlights a variety of innovative approaches to teaching and learning in the community college. Topics covered in the abstracts include: (1) academic partnerships pairing "high-risk" students with a concerned faculty member, counselor, or administrator; (2) teacher-to-teacher learning partnerships; (3)…
Dangouloff-Ros, V; Ronot, M; Lagadec, M; Vilgrain, V
2015-05-01
To evaluate the publication rate of scientific abstracts that were presented orally at the 2008, 2009, and 2010 annual meetings of the French Society of Radiology by French radiologists, and to perform a French regional analysis. Orally presented abstracts were identified by examining online abstract books of the 2008, 2009, and 2010 annual meetings of the French Society of Radiology, and cross-checked by reviewing the paper version of abstracts for the same period. Only abstracts from French teams were selected. The administrative region of submission was noted for each abstract and for each region the total population, the number of active radiologists, the number of active members of the French Society of Radiology and the number of academic radiologists were noted. Imaging subspecialties were also noted. 625 abstracts were identified resulting in 268 publications (publication rate: 43%). The median number of presentations and publications per region was 18 (range: 1-255) and 7 (range: 0-101), respectively. The ratio per million inhabitants was 7.5 and 3 respectively. The median number of presentations and publications per 100 active radiologists (respectively members of the FSR) was 7 and 3 (respectively 10 and 4). The median number of presentations and publications per academic radiologist were 2.6, and 1.2, respectively. The regional variations for each indicator were high (40-180%). Three subspecialties had a publication rate of more than 50%: thoracic imaging (58%), abdominal imaging (52%), and genitourinary imaging (51%). The publication rate of orally presented French scientific abstracts was high, with important variations according to the regions of origin and imaging subspecialties. Copyright © 2015 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.
NASA Technical Reports Server (NTRS)
Rybicki, G. B.; Hummer, D. G.
1991-01-01
A method is presented for solving multilevel transfer problems when nonoverlapping lines and background continuum are present and active continuum transfer is absent. An approximate lambda operator is employed to derive linear, 'preconditioned', statistical-equilibrium equations. A method is described for finding the diagonal elements of the 'true' numerical lambda operator, and therefore for obtaining the coefficients of the equations. Iterations of the preconditioned equations, in conjunction with the transfer equation's formal solution, are used to solve linear equations. Some multilevel problems are considered, including an eleven-level neutral helium atom. Diagonal and tridiagonal approximate lambda operators are utilized in the problems to examine the convergence properties of the method, and it is found to be effective for the line transfer problems.
2011 statistical abstract of the United States
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.
Temporal abstraction-based clinical phenotyping with Eureka!
Post, Andrew R; Kurc, Tahsin; Willard, Richie; Rathod, Himanshu; Mansour, Michel; Pai, Akshatha Kalsanka; Torian, William M; Agravat, Sanjay; Sturm, Suzanne; Saltz, Joel H
2013-01-01
Temporal abstraction, a method for specifying and detecting temporal patterns in clinical databases, is very expressive and performs well, but it is difficult for clinical investigators and data analysts to understand. Such patterns are critical in phenotyping patients using their medical records in research and quality improvement. We have previously developed the Analytic Information Warehouse (AIW), which computes such phenotypes using temporal abstraction but requires software engineers to use. We have extended the AIW's web user interface, Eureka! Clinical Analytics, to support specifying phenotypes using an alternative model that we developed with clinical stakeholders. The software converts phenotypes from this model to that of temporal abstraction prior to data processing. The model can represent all phenotypes in a quality improvement project and a growing set of phenotypes in a multi-site research study. Phenotyping that is accessible to investigators and IT personnel may enable its broader adoption.
NASA Astrophysics Data System (ADS)
Köhn, A.; Guidi, L.; Holzhauer, E.; Maj, O.; Poli, E.; Snicker, A.; Weber, H.
2018-07-01
Plasma turbulence, and edge density fluctuations in particular, can under certain conditions broaden the cross-section of injected microwave beams significantly. This can be a severe problem for applications relying on well-localized deposition of the microwave power, like the control of MHD instabilities. Here we investigate this broadening mechanism as a function of fluctuation level, background density and propagation length in a fusion-relevant scenario using two numerical codes, the full-wave code IPF-FDMC and the novel wave kinetic equation solver WKBeam. The latter treats the effects of fluctuations using a statistical approach, based on an iterative solution of the scattering problem (Born approximation). The full-wave simulations are used to benchmark this approach. The Born approximation is shown to be valid over a large parameter range, including ITER-relevant scenarios.
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,…
Localization Versus Abstraction: A Comparison of Two Search Reduction Techniques
NASA Technical Reports Server (NTRS)
Lansky, Amy L.
1992-01-01
There has been much recent work on the use of abstraction to improve planning behavior and cost. Another technique for dealing with the inherently explosive cost of planning is localization. This paper compares the relative strengths of localization and abstraction in reducing planning search cost. In particular, localization is shown to subsume abstraction. Localization techniques can model the various methods of abstraction that have been used, but also provide a much more flexible framework, with a broader range of benefits.
2017-12-08
Algerian Abstract - April 8th, 1985 Description: What look like pale yellow paint streaks slashing through a mosaic of mottled colors are ridges of wind-blown sand that make up Erg Iguidi, an area of ever-shifting sand dunes extending from Algeria into Mauritania in northwestern Africa. Erg Iguidi is one of several Saharan ergs, or sand seas, where individual dunes often surpass 500 meters-nearly a third of a mile-in both width and height. Credit: USGS/NASA/Landsat 5 To learn more about the Landsat satellite go to: landsat.gsfc.nasa.gov/ NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook
Automatic Generation of Cycle-Approximate TLMs with Timed RTOS Model Support
NASA Astrophysics Data System (ADS)
Hwang, Yonghyun; Schirner, Gunar; Abdi, Samar
This paper presents a technique for automatically generating cycle-approximate transaction level models (TLMs) for multi-process applications mapped to embedded platforms. It incorporates three key features: (a) basic block level timing annotation, (b) RTOS model integration, and (c) RTOS overhead delay modeling. The inputs to TLM generation are application C processes and their mapping to processors in the platform. A processor data model, including pipelined datapath, memory hierarchy and branch delay model is used to estimate basic block execution delays. The delays are annotated to the C code, which is then integrated with a generated SystemC RTOS model. Our abstract RTOS provides dynamic scheduling and inter-process communication (IPC) with processor- and RTOS-specific pre-characterized timing. Our experiments using a MP3 decoder and a JPEG encoder show that timed TLMs, with integrated RTOS models, can be automatically generated in less than a minute. Our generated TLMs simulated three times faster than real-time and showed less than 10% timing error compared to board measurements.
Difference equation state approximations for nonlinear hereditary control problems
NASA Technical Reports Server (NTRS)
Rosen, I. G.
1982-01-01
Discrete approximation schemes for the solution of nonlinear hereditary control problems are constructed. The methods involve approximation by a sequence of optimal control problems in which the original infinite dimensional state equation has been approximated by a finite dimensional discrete difference equation. Convergence of the state approximations is argued using linear semigroup theory and is then used to demonstrate that solutions to the approximating optimal control problems in some sense approximate solutions to the original control problem. Two schemes, one based upon piecewise constant approximation, and the other involving spline functions are discussed. Numerical results are presented, analyzed and used to compare the schemes to other available approximation methods for the solution of hereditary control problems.
Typographic Settings for Structured Abstracts.
ERIC Educational Resources Information Center
Hartley, James
2000-01-01
Lists some of the major typographic variables involved in structured abstracts (containing sub-headings). Illustrates how typography can affect clarity by presenting seven examples that illustrate the effects of these typographic variables in practice. Concludes with a final example of an effective approach. (SR)
Approximate Equation of State for Overdriven and Reflected Detonation Products
NASA Astrophysics Data System (ADS)
Liu, Zhi-Yue; Itoh, Shigeru
2001-06-01
Approximate Equation of State for Overdriven and Reflected Detonation Products Zhi-Yue Liu and Shigeru Itoh Shock Wave and Condensed Matter Research Center, Kumamoto University, 2-39-1 Kurokami, Kumamoto, 860-8555, Japan ABSTRACT There are several types of equations of state (EOS) to describe the isentropic expansion behavior of the detonation products after the explosive is exploded. Of which, Jones-Wilkins-Lee (or JWL) equation and polytropic gas (or gamma-law) equation are most popularly employed owing to either the completely experimental calibration or simple form in expression. However, both equations fail to correctly describe the behavior of detonation products above the Chapman-Jouguet (C-J) state. For this reason, a new form of equation of state is proposed for overcoming this deficiency. The new equation of state is simply a linear combination of JWL and gamma-law equations. The coefficient appeared in the EOS can be obtained by fitting to the data from the overdriven detonation experiments. Results show that this form of EOS not only gives the satisfactory description to the variation of the detonation products in overdriven or reflected state also can simply be incorporated into the hydrodynamic computer codes.
1981-12-01
Development in Initally Caries-Free Naval Recruits" (Abstract #898) , 13. M. R. WIRTHLIN* and E. B. HANCOCK - " Regeneration After Biologic Treat- ment of...These variables can be grouped into four categories: oral condition (N-7), clinical attendance (N=4), personal characteristics (N=4), and record...Histologic examination of the pulp tissue in these teeth were related to the clinical criteria prior to extraction. Clinical criteria associated
Approximation algorithms for planning and control
NASA Technical Reports Server (NTRS)
Boddy, Mark; Dean, Thomas
1989-01-01
A control system operating in a complex environment will encounter a variety of different situations, with varying amounts of time available to respond to critical events. Ideally, such a control system will do the best possible with the time available. In other words, its responses should approximate those that would result from having unlimited time for computation, where the degree of the approximation depends on the amount of time it actually has. There exist approximation algorithms for a wide variety of problems. Unfortunately, the solution to any reasonably complex control problem will require solving several computationally intensive problems. Algorithms for successive approximation are a subclass of the class of anytime algorithms, algorithms that return answers for any amount of computation time, where the answers improve as more time is allotted. An architecture is described for allocating computation time to a set of anytime algorithms, based on expectations regarding the value of the answers they return. The architecture described is quite general, producing optimal schedules for a set of algorithms under widely varying conditions.
Approximation methods in gravitational-radiation theory
NASA Technical Reports Server (NTRS)
Will, C. M.
1986-01-01
The observation of gravitational-radiation damping in the binary pulsar PSR 1913 + 16 and the ongoing experimental search for gravitational waves of extraterrestrial origin have made the theory of gravitational radiation an active branch of classical general relativity. In calculations of gravitational radiation, approximation methods play a crucial role. Recent developments are summarized in two areas in which approximations are important: (a) the quadrupole approxiamtion, which determines the energy flux and the radiation reaction forces in weak-field, slow-motion, source-within-the-near-zone systems such as the binary pulsar; and (b) the normal modes of oscillation of black holes, where the Wentzel-Kramers-Brillouin approximation gives accurate estimates of the complex frequencies of the modes.
Immunogenetic background of patients with autoimmune fatigue syndrome.
Itoh, Y; Igarashi, T; Tatsuma, N; Imai, T; Yoshida, J; Tsuchiya, M; Murakami, M; Fukunaga, Y
2000-10-01
We have previously reported that approximately 50% of children with chronic nonspecific complaints were positive for antinuclear antibodies (ANA), and that a novel autoantibody to a 62 kD protein (anti-Sa) was found in 40% of these ANA-positive patients. Therefore, we proposed a distinct disease entity termed autoimmune fatigue syndrome (AIFS). We hypothesized that if autoimmune mechanisms did play an important role in the pathogenesis of AIFS, it is possible that it is immunogenetically regulated as observed in other autoimmune disorders. In order to examine the immunogenetic background of AIFS patients, HLA-A, -B, -C, and -DR loci were analyzed serologically in 61 AIFS patients. AIFS was found to be positively associated with the class I antigen HLA-B61 and with the class II antigen HLA-DR9, with odds ratios of 2.77 (p = 0.015, Pcorr = 0.48) and 2.60 (p= 0.012, Pcorr = 0.17), respectively. A negative association was also found between AIFS and HLA-DR2 with odds ratio of 0.25 (p = 0.029, Pcorr = 0.041). When comparing anti-Sa positive AIFS patients with healthy controls, the odds ratios associated with HLA-B61, DR9, and DR2 were 3.42 (p = 0.021, Pcorr = 0.22), 3.96 (p = 0.0011, Pcorr = 0.015), and 0.16 (p = 0.0022, Porr = 0.031), respectively. Thus, the HLA associations observed in this study suggested that immunogenetic background might play a role in AIFS.
The Acquisition of Abstract Words by Young Infants
ERIC Educational Resources Information Center
Bergelson, Elika; Swingley, Daniel
2013-01-01
Young infants' learning of words for abstract concepts like "all gone" and "eat," in contrast to their learning of more concrete words like "apple" and "shoe," may follow a relatively protracted developmental course. We examined whether infants know such abstract words. Parents named one of two events shown in side-by-side videos while their…
Contextualizing Action for the Abstraction of Scientific Knowledge
ERIC Educational Resources Information Center
Saglam, Yilmaz
2015-01-01
In this paper, abstraction is associated with an activity in the sense of activity theory by Vygotsky. To him, participation in social activities is a fundamental act for the child in order to achieve higher mental functions. The present paper aimed to experimentally investigate the abstraction process and illustrate how meaning emerges on social…
Difference equation state approximations for nonlinear hereditary control problems
NASA Technical Reports Server (NTRS)
Rosen, I. G.
1984-01-01
Discrete approximation schemes for the solution of nonlinear hereditary control problems are constructed. The methods involve approximation by a sequence of optimal control problems in which the original infinite dimensional state equation has been approximated by a finite dimensional discrete difference equation. Convergence of the state approximations is argued using linear semigroup theory and is then used to demonstrate that solutions to the approximating optimal control problems in some sense approximate solutions to the original control problem. Two schemes, one based upon piecewise constant approximation, and the other involving spline functions are discussed. Numerical results are presented, analyzed and used to compare the schemes to other available approximation methods for the solution of hereditary control problems. Previously announced in STAR as N83-33589
Wang, Ling; Li, Yulin; Li, Jing; Zhang, Mingming; Xu, Lin; Yuan, Wenming; Wang, Gang; Hopewell, Sally
2010-07-08
Due to language limitations, the abstract of journal article may be the only way for people of non-Chinese speaking countries to know about trials in traditional Chinese medicine (TCM). However, little is known about the reporting quality of these trial abstracts. Our study is to assess the reporting quality of abstracts of randomized controlled trials (RCT) published in four leading Chinese medical journals of TCM, and to identify any differences in reporting between the Chinese and English version of the same abstract publication. Two reviewers hand-searched the Chinese Journal of Integrated Traditional and Western Medicine, the Chinese Journal of Integrative Medicine, the China Journal of Chinese Materia Medica and the Chinese Acupuncture & Moxibustion for all abstracts of RCTs published between 2006 and 2007. Two reviewers independently assessed the reporting quality of the Chinese and English version of all eligible abstracts based on a modified version of the CONSORT for reporting randomised trials in journal and conference abstracts (CONSORT for abstracts). We identified a total of 345 RCTs of TCM with both a Chinese and English abstract. More than half of Chinese abstracts reported details of the trial participants (68%; 234/345), control group intervention (52%; 179/345), the number of participants randomized (73%; 253/345) and benefits when interpreting the trial results (55%; 190/345). Reporting of methodological quality or key features of trial design and trial results were poor; only 2% (7/345) included details of the trial design, 3% (11/345) defined the primary outcome, 5% (17/345) described the methods of random sequence generation, and only 4% (13/345) reported the number of participants analyzed. No abstracts provided details on allocation concealment and trial registration. The percentage agreement in reporting (between the Chinese and English version of the same abstract) ranged from 84% to 100% across individual checklist item. The reporting
Approximate number word knowledge before the cardinal principle.
Gunderson, Elizabeth A; Spaepen, Elizabet; Levine, Susan C
2015-02-01
Approximate number word knowledge-understanding the relation between the count words and the approximate magnitudes of sets-is a critical piece of knowledge that predicts later math achievement. However, researchers disagree about when children first show evidence of approximate number word knowledge-before, or only after, they have learned the cardinal principle. In two studies, children who had not yet learned the cardinal principle (subset-knowers) produced sets in response to number words (verbal comprehension task) and produced number words in response to set sizes (verbal production task). As evidence of approximate number word knowledge, we examined whether children's numerical responses increased with increasing numerosity of the stimulus. In Study 1, subset-knowers (ages 3.0-4.2 years) showed approximate number word knowledge above their knower-level on both tasks, but this effect did not extend to numbers above 4. In Study 2, we collected data from a broader age range of subset-knowers (ages 3.1-5.6 years). In this sample, children showed approximate number word knowledge on the verbal production task even when only examining set sizes above 4. Across studies, children's age predicted approximate number word knowledge (above 4) on the verbal production task when controlling for their knower-level, study (1 or 2), and parents' education, none of which predicted approximation ability. Thus, children can develop approximate knowledge of number words up to 10 before learning the cardinal principle. Furthermore, approximate number word knowledge increases with age and might not be closely related to the development of exact number word knowledge. Copyright © 2014 Elsevier Inc. All rights reserved.
Computing Functions by Approximating the Input
ERIC Educational Resources Information Center
Goldberg, Mayer
2012-01-01
In computing real-valued functions, it is ordinarily assumed that the input to the function is known, and it is the output that we need to approximate. In this work, we take the opposite approach: we show how to compute the values of some transcendental functions by approximating the input to these functions, and obtaining exact answers for their…
Comprehension of concrete and abstract words in semantic dementia
Jefferies, Elizabeth; Patterson, Karalyn; Jones, Roy W.; Lambon Ralph, Matthew A.
2009-01-01
The vast majority of brain-injured patients with semantic impairment have better comprehension of concrete than abstract words. In contrast, several patients with semantic dementia (SD), who show circumscribed atrophy of the anterior temporal lobes bilaterally, have been reported to show reverse imageability effects, i.e., relative preservation of abstract knowledge. Although these reports largely concern individual patients, some researchers have recently proposed that superior comprehension of abstract concepts is a characteristic feature of SD. This would imply that the anterior temporal lobes are particularly crucial for processing sensory aspects of semantic knowledge, which are associated with concrete not abstract concepts. However, functional neuroimaging studies of healthy participants do not unequivocally predict reverse imageability effects in SD because the temporal poles sometimes show greater activation for more abstract concepts. We examined a case-series of eleven SD patients on a synonym judgement test that orthogonally varied the frequency and imageability of the items. All patients had higher success rates for more imageable as well as more frequent words, suggesting that (a) the anterior temporal lobes underpin semantic knowledge for both concrete and abstract concepts, (b) more imageable items – perhaps due to their richer multimodal representations – are typically more robust in the face of global semantic degradation and (c) reverse imageability effects are not a characteristic feature of SD. PMID:19586212
Kaye, Stephen B
2009-04-01
To provide a scalar measure of refractive error, based on geometric lens power through principal, orthogonal and oblique meridians, that is not limited to the paraxial and sag height approximations. A function is derived to model sections through the principal meridian of a lens, followed by rotation of the section through orthogonal and oblique meridians. Average focal length is determined using the definition for the average of a function. Average univariate power in the principal meridian (including spherical aberration), can be computed from the average of a function over the angle of incidence as determined by the parameters of the given lens, or adequately computed from an integrated series function. Average power through orthogonal and oblique meridians, can be similarly determined using the derived formulae. The widely used computation for measuring refractive error, the spherical equivalent, introduces non-constant approximations, leading to a systematic bias. The equations proposed provide a good univariate representation of average lens power and are not subject to a systematic bias. They are particularly useful for the analysis of aggregate data, correlating with biological treatment variables and for developing analyses, which require a scalar equivalent representation of refractive power.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berkel, M. van; Fellow of the Japan Society for the Promotion of Science; FOM Institute DIFFER-Dutch Institute for Fundamental Energy Research, Association EURATOM- FOM, Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein
2014-11-15
In this paper, a number of new approximations are introduced to estimate the perturbative diffusivity (χ), convectivity (V), and damping (τ) in cylindrical geometry. For this purpose, the harmonic components of heat waves induced by localized deposition of modulated power are used. The approximations are based on semi-infinite slab approximations of the heat equation. The main result is the approximation of χ under the influence of V and τ based on the phase of two harmonics making the estimate less sensitive to calibration errors. To understand why the slab approximations can estimate χ well in cylindrical geometry, the relationships betweenmore » heat transport models in slab and cylindrical geometry are studied. In addition, the relationship between amplitude and phase with respect to their derivatives, used to estimate χ, is discussed. The results are presented in terms of the relative error for the different derived approximations for different values of frequency, transport coefficients, and dimensionless radius. The approximations show a significant region in which χ, V, and τ can be estimated well, but also regions in which the error is large. Also, it is shown that some compensation is necessary to estimate V and τ in a cylindrical geometry. On the other hand, errors resulting from the simplified assumptions are also discussed showing that estimating realistic values for V and τ based on infinite domains will be difficult in practice. This paper is the first part (Part I) of a series of three papers. In Part II and Part III, cylindrical approximations based directly on semi-infinite cylindrical domain (outward propagating heat pulses) and inward propagating heat pulses in a cylindrical domain, respectively, will be treated.« less
International Early Childhood Resources from Educational Research Abstracts Online (ERA)
ERIC Educational Resources Information Center
International Journal of Early Years Education, 2004
2004-01-01
This annotated bibliography provides abstracts for 14 resources relating to early childhood around the world. Each annotation contains: title; author name(s); Educational Research Abstract; Abstract number; Source (name of journal in which the resource was published); ISSN of the journal in which the resource was published; and Issue (journal…
NASA Patent Abstracts: A Continuing Bibliography. Supplement 54
NASA Technical Reports Server (NTRS)
1999-01-01
The NASA Patent Abstracts Bibliography is a semiannual NASA publication containing comprehensive abstracts of NASA owned inventions covered by U.S. patents and applications for patent. The citations included in the bibliography arrangement of citations were originally published in NASA's Scientific and Technical Aerospace Reports (STAR) and cover STAR announcements made since May 1969. The citations published in this issue cover the period June 1998 through December 1998. This issue includes 10 major subject divisions separated into 76 specific categories and one general category/division. Each entry consists of a STAR citation accompanied by an abstract and, when appropriate, a key illustration taken from the patent or application for patent. Entries are arranged by subject category in ascending order.
Pawlak Algebra and Approximate Structure on Fuzzy Lattice
Zhuang, Ying; Liu, Wenqi; Wu, Chin-Chia; Li, Jinhai
2014-01-01
The aim of this paper is to investigate the general approximation structure, weak approximation operators, and Pawlak algebra in the framework of fuzzy lattice, lattice topology, and auxiliary ordering. First, we prove that the weak approximation operator space forms a complete distributive lattice. Then we study the properties of transitive closure of approximation operators and apply them to rough set theory. We also investigate molecule Pawlak algebra and obtain some related properties. PMID:25152922
Pawlak algebra and approximate structure on fuzzy lattice.
Zhuang, Ying; Liu, Wenqi; Wu, Chin-Chia; Li, Jinhai
2014-01-01
The aim of this paper is to investigate the general approximation structure, weak approximation operators, and Pawlak algebra in the framework of fuzzy lattice, lattice topology, and auxiliary ordering. First, we prove that the weak approximation operator space forms a complete distributive lattice. Then we study the properties of transitive closure of approximation operators and apply them to rough set theory. We also investigate molecule Pawlak algebra and obtain some related properties.
NASA Astrophysics Data System (ADS)
Voloshinov, V. V.
2018-03-01
In computations related to mathematical programming problems, one often has to consider approximate, rather than exact, solutions satisfying the constraints of the problem and the optimality criterion with a certain error. For determining stopping rules for iterative procedures, in the stability analysis of solutions with respect to errors in the initial data, etc., a justified characteristic of such solutions that is independent of the numerical method used to obtain them is needed. A necessary δ-optimality condition in the smooth mathematical programming problem that generalizes the Karush-Kuhn-Tucker theorem for the case of approximate solutions is obtained. The Lagrange multipliers corresponding to the approximate solution are determined by solving an approximating quadratic programming problem.
Calibration of an Ultra-Low-Background Proportional Counter for Measuring 37Ar
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seifert, Allen; Aalseth, Craig E.; Bonicalzi, Ricco
Abstract. An ultra-low-background proportional counter (ULBPC) design has been developed at Pacific Northwest National Laboratory (PNNL) using clean materials, primarily electrochemically-purified copper. This detector, along with an ultra-low-background counting system (ULBCS), was developed to complement a new shallow underground laboratory (30 meters water-equivalent) constructed at PNNL. The ULBCS design includes passive neutron and gamma shielding, along with an active cosmic-veto system. This system provides a capability for making ultra-sensitive measurements to support applications like age-dating soil hydrocarbons with 14C/3H, age-dating of groundwater with 39Ar, and soil-gas assay for 37Ar to support On-Site Inspection (OSI). On-Site Inspection is a key componentmore » of the verification regime for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Measurements of radionuclides created by an underground nuclear explosion are valuable signatures of a Treaty violation. For OSI, the 35-day half-life of 37Ar, produced from neutron interactions with calcium in soil, provides both high specific activity and sufficient time for inspection before decay limits sensitivity. This work describes the calibration techniques and analysis methods developed to enable quantitative measurements of 37Ar samples over a broad range of pressures. These efforts, along with parallel work in progress on gas chemistry separation, are expected to provide a significant new capability for 37Ar soil gas background studies.« less
NASA Astrophysics Data System (ADS)
Kim, SungKun; Lee, Hunpyo
2017-06-01
Via a dynamical cluster approximation with N c = 4 in combination with a semiclassical approximation (DCA+SCA), we study the doped two-dimensional Hubbard model. We obtain a plaquette antiferromagnetic (AF) Mott insulator, a plaquette AF ordered metal, a pseudogap (or d-wave superconductor) and a paramagnetic metal by tuning the doping concentration. These features are similar to the behaviors observed in copper-oxide superconductors and are in qualitative agreement with the results calculated by the cluster dynamical mean field theory with the continuous-time quantum Monte Carlo (CDMFT+CTQMC) approach. The results of our DCA+SCA differ from those of the CDMFT+CTQMC approach in that the d-wave superconducting order parameters are shown even in the high doped region, unlike the results of the CDMFT+CTQMC approach. We think that the strong plaquette AF orderings in the dynamical cluster approximation (DCA) with N c = 4 suppress superconducting states with increasing doping up to strongly doped region, because frozen dynamical fluctuations in a semiclassical approximation (SCA) approach are unable to destroy those orderings. Our calculation with short-range spatial fluctuations is initial research, because the SCA can manage long-range spatial fluctuations in feasible computational times beyond the CDMFT+CTQMC tool. We believe that our future DCA+SCA calculations should supply information on the fully momentum-resolved physical properties, which could be compared with the results measured by angle-resolved photoemission spectroscopy experiments.
On Teaching Abstraction in Computer Science to Novices
ERIC Educational Resources Information Center
Armoni, Michal
2013-01-01
Abstraction is a key concept in CS, one of the most fundamental ideas underlying CS and its practice. However, teaching this soft concept to novices is a very difficult task, as discussed by many CSE experts. This paper discusses this issue, and suggests a general framework for teaching abstraction in CS to novices, a framework that would fit into…
Experiencing Art: The Influence of Expertise and Painting Abstraction Level
Pihko, Elina; Virtanen, Anne; Saarinen, Veli-Matti; Pannasch, Sebastian; Hirvenkari, Lotta; Tossavainen, Timo; Haapala, Arto; Hari, Riitta
2011-01-01
How does expertise influence the perception of representational and abstract paintings? We asked 20 experts on art history and 20 laypersons to explore and evaluate a series of paintings ranging in style from representational to abstract in five categories. We compared subjective esthetic judgments and emotional evaluations, gaze patterns, and electrodermal reactivity between the two groups of participants. The level of abstraction affected esthetic judgments and emotional valence ratings of the laypersons but had no effect on the opinions of the experts: the laypersons’ esthetic and emotional ratings were highest for representational paintings and lowest for abstract paintings, whereas the opinions of the experts were independent of the abstraction level. The gaze patterns of both groups changed as the level of abstraction increased: the number of fixations and the length of the scanpaths increased while the duration of the fixations decreased. The viewing strategies – reflected in the target, location, and path of the fixations – however indicated that experts and laypersons paid attention to different aspects of the paintings. The electrodermal reactivity did not vary according to the level of abstraction in either group but expertise was reflected in weaker responses, compared with laypersons, to information received about the paintings. PMID:21941475
Yalçınkaya, Merter; Bagatur, Erdem
2013-01-01
The aim of this study was to evaluate the publication rates of full-text articles after presentation of abstracts at a Turkish National Orthopaedics and Traumatology Congress, determine the time lag from the congress date to publication of full-text articles and assess the consistency between abstracts and the subsequent publications. All abstracts from the scientific program of the 20th Turkish National Orthopaedics and Traumatology Congress (2007) were identified and computerized PubMed searches were conducted to determine whether an abstract had been followed by publication of a full-text article and key features were compared to evaluate their consistency. The time lag to publication and the impact factors of the journals where the articles were published were noted. Of the 770 abstracts (264 oral, 506 poster presentations), 227 (29.5%) were followed by a full-text and 116 (44%) of the 264 oral and 111 (22%) of the 506 poster presentations were published. The mean time to publication was 14.9±16.075 (range: 33 to 55) months. Thirty-three (14.5%) were published prior to the presentation at the congress. The likelihood of publication decreased after the third year (26 of 227, 11.5%). A total of 182 (80.2%) articles showed inconsistencies with the abstract; 74 (32.6%) minor, 14 (6.2%) major, and 94 (41.4%) minor and major inconsistencies. The mean impact factor of the journals was 1.152±0.858. The vast majority of abstracts presented at this congress were not followed by publication of a full-text article. Additionally, frequent inconsistencies between the final published article and the original abstract indicated the inadequacy of quality of reporting in abstracts.
The neural representation of abstract words: the role of emotion.
Vigliocco, Gabriella; Kousta, Stavroula-Thaleia; Della Rosa, Pasquale Anthony; Vinson, David P; Tettamanti, Marco; Devlin, Joseph T; Cappa, Stefano F
2014-07-01
It is generally assumed that abstract concepts are linguistically coded, in line with imaging evidence of greater engagement of the left perisylvian language network for abstract than concrete words (Binder JR, Desai RH, Graves WW, Conant LL. 2009. Where is the semantic system? A critical review and meta-analysis of 120 functional neuroimaging studies. Cerebral Cortex. 19:2767-2796; Wang J, Conder JA, Blitzer DN, Shinkareva SV. 2010. Neural representation of abstract and concrete concepts: A meta-analysis of neuroimaging studies. Hum Brain Map. 31:1459-1468). Recent behavioral work, which used tighter matching of items than previous studies, however, suggests that abstract concepts also entail affective processing to a greater extent than concrete concepts (Kousta S-T, Vigliocco G, Vinson DP, Andrews M, Del Campo E. The representation of abstract words: Why emotion matters. J Exp Psychol Gen. 140:14-34). Here we report a functional magnetic resonance imaging experiment that shows greater engagement of the rostral anterior cingulate cortex, an area associated with emotion processing (e.g., Etkin A, Egner T, Peraza DM, Kandel ER, Hirsch J. 2006. Resolving emotional conflict: A role for the rostral anterior cingulate cortex in modulating activity in the amygdala. Neuron. 52:871), in abstract processing. For abstract words, activation in this area was modulated by the hedonic valence (degree of positive or negative affective association) of our items. A correlation analysis of more than 1,400 English words further showed that abstract words, in general, receive higher ratings for affective associations (both valence and arousal) than concrete words, supporting the view that engagement of emotional processing is generally required for processing abstract words. We argue that these results support embodiment views of semantic representation, according to which, whereas concrete concepts are grounded in our sensory-motor experience, affective experience is crucial in the
ERIC Educational Resources Information Center
1971
This document is an English-language abstract (approximately 1,500 words) of a French report in response to an IBE questionnaire. Studies conducted by the Ministry of Information have revealed that particularly serious educational wastage has been taking place on both the elementary and secondary levels, and the French education system is not well…
Differential equation based method for accurate approximations in optimization
NASA Technical Reports Server (NTRS)
Pritchard, Jocelyn I.; Adelman, Howard M.
1990-01-01
This paper describes a method to efficiently and accurately approximate the effect of design changes on structural response. The key to this new method is to interpret sensitivity equations as differential equations that may be solved explicitly for closed form approximations, hence, the method is denoted the Differential Equation Based (DEB) method. Approximations were developed for vibration frequencies, mode shapes and static displacements. The DEB approximation method was applied to a cantilever beam and results compared with the commonly-used linear Taylor series approximations and exact solutions. The test calculations involved perturbing the height, width, cross-sectional area, tip mass, and bending inertia of the beam. The DEB method proved to be very accurate, and in msot cases, was more accurate than the linear Taylor series approximation. The method is applicable to simultaneous perturbation of several design variables. Also, the approximations may be used to calculate other system response quantities. For example, the approximations for displacement are used to approximate bending stresses.
Differential equation based method for accurate approximations in optimization
NASA Technical Reports Server (NTRS)
Pritchard, Jocelyn I.; Adelman, Howard M.
1990-01-01
A method to efficiently and accurately approximate the effect of design changes on structural response is described. The key to this method is to interpret sensitivity equations as differential equations that may be solved explicitly for closed form approximations, hence, the method is denoted the Differential Equation Based (DEB) method. Approximations were developed for vibration frequencies, mode shapes and static displacements. The DEB approximation method was applied to a cantilever beam and results compared with the commonly-used linear Taylor series approximations and exact solutions. The test calculations involved perturbing the height, width, cross-sectional area, tip mass, and bending inertia of the beam. The DEB method proved to be very accurate, and in most cases, was more accurate than the linear Taylor series approximation. The method is applicable to simultaneous perturbation of several design variables. Also, the approximations may be used to calculate other system response quantities. For example, the approximations for displacements are used to approximate bending stresses.