UPPER BOUND RISK ESTIMATES FOR MIXTURES OF CARCINOGENS

EPA Science Inventory

The excess cancer risk that might result from exposure to a mixture of chemical carcinogens usually is estimated with data from experiments conducted on individual chemicals. An upper bound on the total excess risk is estimated commonly by summing individual upper bound risk esti...

Influence of gravitation on the propagation of electromagnetic radiation

NASA Technical Reports Server (NTRS)

Mashhoon, B.

1975-01-01

The existence of a general helicity-rotation coupling is demonstrated for electromagnetic waves propagating in the field of a slowly rotating body and in the Goedel universe. This coupling leads to differential focusing of circularly polarized radiation by a gravitational field which is detectable for a rapidly rotating collapsed body. The electromagnetic perturbations and their frequency spectrum are given for the Goedel universe. The spectrum of frequencies is bounded from below by the characteristic rotation frequency of the Goedel universe. If the universe were rotating, the differential focusing effect would be extremely small due to the present upper limit on the anisotropy of the microwave background radiation.

DD production and their interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Yanrui; Oka, Makoto; Takizawa, Makoto

2010-07-01

S- and P-wave DD scatterings are studied in a meson exchange model with the coupling constants obtained in the heavy quark effective theory. With the extracted P-wave phase shifts and the separable potential approximation, we include the DD rescattering effect and investigate the production process e{sup +}e{sup -{yields}}DD. We find that it is difficult to explain the anomalous line shape observed by the BES Collaboration with this mechanism. Combining our model calculation and the experimental measurement, we estimate the upper limit of the nearly universal cutoff parameter to be around 2 GeV. With this number, the upper limits of themore » binding energies of the S-wave DD and BB bound states are obtained. Assuming that the S-wave and P-wave interactions rely on the same cutoff, our study provides a way of extracting the information about S-wave molecular bound states from the P-wave meson pair production.« less

Upper bounds of deformation in the Upper Rhine Graben from GPS data - First results from GURN (GNSS Upper Rhine Graben Network)

NASA Astrophysics Data System (ADS)

Masson, Frederic; Knoepfler, Andreas; Mayer, Michael; Ulrich, Patrice; Heck, Bernhard

2010-05-01

In September 2008, the Institut de Physique du Globe de Strasbourg (Ecole et Observatoire des Sciences de la Terre, EOST) and the Geodetic Institute (GIK) of Karlsruhe University (TH) established a transnational cooperation called GURN (GNSS Upper Rhine Graben Network). Within the GURN initiative these institutions are cooperating in order to establish a highly precise and highly sensitive network of permanently operating GNSS sites for the detection of crustal movements in the Upper Rhine Graben region. At the beginning, the network consisted of the permanently operating GNSS sites of SAPOS®-Baden-Württemberg, different data providers in France (e.g. EOST, Teria, RGP) and some further sites (e.g. IGS). In July 2009, the network was extended to the South when swisstopo (Switzerland) and to the North when SAPOS®-Rheinland-Pfalz joined GURN. Therefore, actually the GNSS network consists of approx. 80 permanently operating reference sites. The presentation will discuss the actual status of GURN, main research goals, and will present first results concerning the data quality as well as time series of a first reprocessing of all available data since 2002 using GAMIT/GLOBK (EOST working group) and the Bernese GPS Software (GIK working group). Based on these time series, the velocity as well as strain fields will be calculated in the future. The GURN initiative is also aiming for the estimation of the upper bounds of deformation in the Upper Rhine Graben region.

Upper bound on the slope of steady water waves with small adverse vorticity

NASA Astrophysics Data System (ADS)

So, Seung Wook; Strauss, Walter A.

2018-03-01

We consider the angle of inclination (with respect to the horizontal) of the profile of a steady 2D inviscid symmetric periodic or solitary water wave subject to gravity. There is an upper bound of 31.15° in the irrotational case [1] and an upper bound of 45° in the case of favorable vorticity [13]. On the other hand, if the vorticity is adverse, the profile can become vertical. We prove here that if the adverse vorticity is sufficiently small, then the angle still has an upper bound which is slightly larger than 45°.

Data envelopment analysis with upper bound on output to measure efficiency performance of departments in Malaikulsaleh University

NASA Astrophysics Data System (ADS)

Abdullah, Dahlan; Suwilo, Saib; Tulus; Mawengkang, Herman; Efendi, Syahril

2017-09-01

The higher education system in Indonesia can be considered not only as an important source of developing knowledge in the country, but also could create positive living conditions for the country. Therefore it is not surprising that enrollments in higher education continue to expand. However, the implication of this situation, the Indonesian government is necessarily to support more funds. In the interest of accountability, it is essential to measure the efficiency for this higher institution. Data envelopment analysis (DEA) is a method to evaluate the technical efficiency of production units which have multiple input and output. The higher learning institution considered in this paper is Malikussaleh University located in Lhokseumawe, a city in Aceh province of Indonesia. This paper develops a method to evaluate efficiency for all departments in Malikussaleh University using DEA with bounded output. Accordingly, we present some important differences in efficiency of those departments. Finally we discuss the effort should be done by these departments in order to become efficient.

Calculation of upper confidence bounds on proportion of area containing not-sampled vegetation types: An application to map unit definition for existing vegetation maps

Treesearch

Paul L. Patterson; Mark Finco

2011-01-01

This paper explores the information forest inventory data can produce regarding forest types that were not sampled and develops the equations necessary to define the upper confidence bounds on not-sampled forest types. The problem is reduced to a Bernoulli variable. This simplification allows the upper confidence bounds to be calculated based on Cochran (1977)....

Aggregating quantum repeaters for the quantum internet

NASA Astrophysics Data System (ADS)

Azuma, Koji; Kato, Go

2017-09-01

The quantum internet holds promise for accomplishing quantum teleportation and unconditionally secure communication freely between arbitrary clients all over the globe, as well as the simulation of quantum many-body systems. For such a quantum internet protocol, a general fundamental upper bound on the obtainable entanglement or secret key has been derived [K. Azuma, A. Mizutani, and H.-K. Lo, Nat. Commun. 7, 13523 (2016), 10.1038/ncomms13523]. Here we consider its converse problem. In particular, we present a universal protocol constructible from any given quantum network, which is based on running quantum repeater schemes in parallel over the network. For arbitrary lossy optical channel networks, our protocol has no scaling gap with the upper bound, even based on existing quantum repeater schemes. In an asymptotic limit, our protocol works as an optimal entanglement or secret-key distribution over any quantum network composed of practical channels such as erasure channels, dephasing channels, bosonic quantum amplifier channels, and lossy optical channels.

Heterogeneous upper-bound finite element limit analysis of masonry walls out-of-plane loaded

NASA Astrophysics Data System (ADS)

Milani, G.; Zuccarello, F. A.; Olivito, R. S.; Tralli, A.

2007-11-01

A heterogeneous approach for FE upper bound limit analyses of out-of-plane loaded masonry panels is presented. Under the assumption of associated plasticity for the constituent materials, mortar joints are reduced to interfaces with a Mohr Coulomb failure criterion with tension cut-off and cap in compression, whereas for bricks both limited and unlimited strength are taken into account. At each interface, plastic dissipation can occur as a combination of out-of-plane shear, bending and torsion. In order to test the reliability of the model proposed, several examples of dry-joint panels out-of-plane loaded tested at the University of Calabria (Italy) are discussed. Numerical results are compared with experimental data for three different series of walls at different values of the in-plane compressive vertical loads applied. The comparisons show that reliable predictions of both collapse loads and failure mechanisms can be obtained by means of the numerical procedure employed.

Modeling of magnitude distributions by the generalized truncated exponential distribution

NASA Astrophysics Data System (ADS)

Raschke, Mathias

2015-01-01

The probability distribution of the magnitude can be modeled by an exponential distribution according to the Gutenberg-Richter relation. Two alternatives are the truncated exponential distribution (TED) and the cutoff exponential distribution (CED). The TED is frequently used in seismic hazard analysis although it has a weak point: when two TEDs with equal parameters except the upper bound magnitude are mixed, then the resulting distribution is not a TED. Inversely, it is also not possible to split a TED of a seismic region into TEDs of subregions with equal parameters except the upper bound magnitude. This weakness is a principal problem as seismic regions are constructed scientific objects and not natural units. We overcome it by the generalization of the abovementioned exponential distributions: the generalized truncated exponential distribution (GTED). Therein, identical exponential distributions are mixed by the probability distribution of the correct cutoff points. This distribution model is flexible in the vicinity of the upper bound magnitude and is equal to the exponential distribution for smaller magnitudes. Additionally, the exponential distributions TED and CED are special cases of the GTED. We discuss the possible ways of estimating its parameters and introduce the normalized spacing for this purpose. Furthermore, we present methods for geographic aggregation and differentiation of the GTED and demonstrate the potential and universality of our simple approach by applying it to empirical data. The considerable improvement by the GTED in contrast to the TED is indicated by a large difference between the corresponding values of the Akaike information criterion.

Higher order terms in the inflation potential and the lower bound on the tensor to scalar ratio r

DOE Office of Scientific and Technical Information (OSTI.GOV)

Destri, C., E-mail: Claudio.Destri@mib.infn.it; Vega, H.J. de, E-mail: devega@lpthe.jussieu.fr; Observatoire de Paris, LERMA, Laboratoire Associe au CNRS UMR 8112, 61, Avenue de l'Observatoire, 75014 Paris

Research Highlights: > In Ginsburg-Landau (G-L) approach data favors new inflation over chaotic inflation. > n{sub s} and r fall inside a universal banana-shaped region in G-L new inflation. > The banana region for the observed value n{sub s}=0.964 implies 0.021 Fermion condensate inflaton potential is a double well in the G-L class. - Abstract: The MCMC analysis of the CMB + LSS data in the context of the Ginsburg-Landau approach to inflation indicated that the fourth degree double-well inflaton potential in new inflation gives an excellent fit of the present CMB and LSS data. This provided a lowermore » bound for the ratio r of the tensor to scalar fluctuations and as most probable value r {approx_equal} 0.05, within reach of the forthcoming CMB observations. In this paper we systematically analyze the effects of arbitrarily higher order terms in the inflaton potential on the CMB observables: spectral index n{sub s} and ratio r. Furthermore, we compute in close form the inflaton potential dynamically generated when the inflaton field is a fermion condensate in the inflationary universe. This inflaton potential turns out to belong to the Ginsburg-Landau class too. The theoretical values in the (n{sub s}, r) plane for all double well inflaton potentials in the Ginsburg-Landau approach (including the potential generated by fermions) fall inside a universal banana-shaped region B. The upper border of the banana-shaped region B is given by the fourth order double-well potential and provides an upper bound for the ratio r. The lower border of B is defined by the quadratic plus an infinite barrier inflaton potential and provides a lower bound for the ratio r. For example, the current best value of the spectral index n{sub s} = 0.964, implies r is in the interval: 0.021 < r < 0.053. Interestingly enough, this range is within reach of forthcoming CMB observations.« less

Calculation of upper confidence bounds on not-sampled vegetation types using a systematic grid sample: An application to map unit definition for existing vegetation maps

Treesearch

Paul L. Patterson; Mark Finco

2009-01-01

This paper explores the information FIA data can produce regarding forest types that were not sampled and develops the equations necessary to define the upper confidence bounds on not-sampled forest types. The problem is reduced to a Bernoulli variable. This simplification allows the upper confidence bounds to be calculated based on Cochran (1977). Examples are...

General upper bound on single-event upset rate. [due to ionizing radiation in orbiting vehicle avionics

NASA Technical Reports Server (NTRS)

Chlouber, Dean; O'Neill, Pat; Pollock, Jim

1990-01-01

A technique of predicting an upper bound on the rate at which single-event upsets due to ionizing radiation occur in semiconducting memory cells is described. The upper bound on the upset rate, which depends on the high-energy particle environment in earth orbit and accelerator cross-section data, is given by the product of an upper-bound linear energy-transfer spectrum and the mean cross section of the memory cell. Plots of the spectrum are given for low-inclination and polar orbits. An alternative expression for the exact upset rate is also presented. Both methods rely only on experimentally obtained cross-section data and are valid for sensitive bit regions having arbitrary shape.

Upper bounds on secret-key agreement over lossy thermal bosonic channels

NASA Astrophysics Data System (ADS)

Kaur, Eneet; Wilde, Mark M.

2017-12-01

Upper bounds on the secret-key-agreement capacity of a quantum channel serve as a way to assess the performance of practical quantum-key-distribution protocols conducted over that channel. In particular, if a protocol employs a quantum repeater, achieving secret-key rates exceeding these upper bounds is evidence of having a working quantum repeater. In this paper, we extend a recent advance [Liuzzo-Scorpo et al., Phys. Rev. Lett. 119, 120503 (2017), 10.1103/PhysRevLett.119.120503] in the theory of the teleportation simulation of single-mode phase-insensitive Gaussian channels such that it now applies to the relative entropy of entanglement measure. As a consequence of this extension, we find tighter upper bounds on the nonasymptotic secret-key-agreement capacity of the lossy thermal bosonic channel than were previously known. The lossy thermal bosonic channel serves as a more realistic model of communication than the pure-loss bosonic channel, because it can model the effects of eavesdropper tampering and imperfect detectors. An implication of our result is that the previously known upper bounds on the secret-key-agreement capacity of the thermal channel are too pessimistic for the practical finite-size regime in which the channel is used a finite number of times, and so it should now be somewhat easier to witness a working quantum repeater when using secret-key-agreement capacity upper bounds as a benchmark.

Upper bounds on the error probabilities and asymptotic error exponents in quantum multiple state discrimination

DOE Office of Scientific and Technical Information (OSTI.GOV)

Audenaert, Koenraad M. R., E-mail: koenraad.audenaert@rhul.ac.uk; Department of Physics and Astronomy, University of Ghent, S9, Krijgslaan 281, B-9000 Ghent; Mosonyi, Milán, E-mail: milan.mosonyi@gmail.com

2014-10-01

We consider the multiple hypothesis testing problem for symmetric quantum state discrimination between r given states σ₁, …, σ{sub r}. By splitting up the overall test into multiple binary tests in various ways we obtain a number of upper bounds on the optimal error probability in terms of the binary error probabilities. These upper bounds allow us to deduce various bounds on the asymptotic error rate, for which it has been hypothesized that it is given by the multi-hypothesis quantum Chernoff bound (or Chernoff divergence) C(σ₁, …, σ{sub r}), as recently introduced by Nussbaum and Szkoła in analogy with Salikhov'smore » classical multi-hypothesis Chernoff bound. This quantity is defined as the minimum of the pairwise binary Chernoff divergences min{sub j« less

Upper bounds on sequential decoding performance parameters

NASA Technical Reports Server (NTRS)

Jelinek, F.

1974-01-01

This paper presents the best obtainable random coding and expurgated upper bounds on the probabilities of undetectable error, of t-order failure (advance to depth t into an incorrect subset), and of likelihood rise in the incorrect subset, applicable to sequential decoding when the metric bias G is arbitrary. Upper bounds on the Pareto exponent are also presented. The G-values optimizing each of the parameters of interest are determined, and are shown to lie in intervals that in general have nonzero widths. The G-optimal expurgated bound on undetectable error is shown to agree with that for maximum likelihood decoding of convolutional codes, and that on failure agrees with the block code expurgated bound. Included are curves evaluating the bounds for interesting choices of G and SNR for a binary-input quantized-output Gaussian additive noise channel.

Asymmetric thermal-relic dark matter: Sommerfeld-enhanced freeze-out, annihilation signals and unitarity bounds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baldes, Iason; Petraki, Kalliopi, E-mail: iason.baldes@desy.de, E-mail: kpetraki@lpthe.jussieu.fr

Dark matter that possesses a particle-antiparticle asymmetry and has thermalised in the early universe, requires a larger annihilation cross-section compared to symmetric dark matter, in order to deplete the dark antiparticles and account for the observed dark matter density. The annihilation cross-section determines the residual symmetric component of dark matter, which may give rise to annihilation signals during CMB and inside haloes today. We consider dark matter with long-range interactions, in particular dark matter coupled to a light vector or scalar force mediator. We compute the couplings required to attain a final antiparticle-to-particle ratio after the thermal freeze-out of themore » annihilation processes in the early universe, and then estimate the late-time annihilation signals. We show that, due to the Sommerfeld enhancement, highly asymmetric dark matter with long-range interactions can have a significant annihilation rate, potentially larger than symmetric dark matter of the same mass with contact interactions. We discuss caveats in this estimation, relating to the formation of stable bound states. Finally, we consider the non-relativistic partial-wave unitarity bound on the inelastic cross-section, we discuss why it can be realised only by long-range interactions, and showcase the importance of higher partial waves in this regime of large inelasticity. We derive upper bounds on the mass of symmetric and asymmetric thermal-relic dark matter for s -wave and p -wave annihilation, and exhibit how these bounds strengthen as the dark asymmetry increases.« less

Entropy production of doubly stochastic quantum channels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Müller-Hermes, Alexander, E-mail: muellerh@posteo.net; Department of Mathematical Sciences, University of Copenhagen, 2100 Copenhagen; Stilck França, Daniel, E-mail: dsfranca@mytum.de

2016-02-15

We study the entropy increase of quantum systems evolving under primitive, doubly stochastic Markovian noise and thus converging to the maximally mixed state. This entropy increase can be quantified by a logarithmic-Sobolev constant of the Liouvillian generating the noise. We prove a universal lower bound on this constant that stays invariant under taking tensor-powers. Our methods involve a new comparison method to relate logarithmic-Sobolev constants of different Liouvillians and a technique to compute logarithmic-Sobolev inequalities of Liouvillians with eigenvectors forming a projective representation of a finite abelian group. Our bounds improve upon similar results established before and as an applicationmore » we prove an upper bound on continuous-time quantum capacities. In the last part of this work we study entropy production estimates of discrete-time doubly stochastic quantum channels by extending the framework of discrete-time logarithmic-Sobolev inequalities to the quantum case.« less

How entangled can a multi-party system possibly be?

NASA Astrophysics Data System (ADS)

Qi, Liqun; Zhang, Guofeng; Ni, Guyan

2018-06-01

The geometric measure of entanglement of a pure quantum state is defined to be its distance to the space of pure product (separable) states. Given an n-partite system composed of subsystems of dimensions d1 , … ,dn, an upper bound for maximally allowable entanglement is derived in terms of geometric measure of entanglement. This upper bound is characterized exclusively by the dimensions d1 , … ,dn of composite subsystems. Numerous examples demonstrate that the upper bound appears to be reasonably tight.

A new upper bound for the norm of interval matrices with application to robust stability analysis of delayed neural networks.

PubMed

Faydasicok, Ozlem; Arik, Sabri

2013-08-01

The main problem with the analysis of robust stability of neural networks is to find the upper bound norm for the intervalized interconnection matrices of neural networks. In the previous literature, the major three upper bound norms for the intervalized interconnection matrices have been reported and they have been successfully applied to derive new sufficient conditions for robust stability of delayed neural networks. One of the main contributions of this paper will be the derivation of a new upper bound for the norm of the intervalized interconnection matrices of neural networks. Then, by exploiting this new upper bound norm of interval matrices and using stability theory of Lyapunov functionals and the theory of homomorphic mapping, we will obtain new sufficient conditions for the existence, uniqueness and global asymptotic stability of the equilibrium point for the class of neural networks with discrete time delays under parameter uncertainties and with respect to continuous and slope-bounded activation functions. The results obtained in this paper will be shown to be new and they can be considered alternative results to previously published corresponding results. We also give some illustrative and comparative numerical examples to demonstrate the effectiveness and applicability of the proposed robust stability condition. Copyright © 2013 Elsevier Ltd. All rights reserved.

Estimation variance bounds of importance sampling simulations in digital communication systems

NASA Technical Reports Server (NTRS)

Lu, D.; Yao, K.

1991-01-01

In practical applications of importance sampling (IS) simulation, two basic problems are encountered, that of determining the estimation variance and that of evaluating the proper IS parameters needed in the simulations. The authors derive new upper and lower bounds on the estimation variance which are applicable to IS techniques. The upper bound is simple to evaluate and may be minimized by the proper selection of the IS parameter. Thus, lower and upper bounds on the improvement ratio of various IS techniques relative to the direct Monte Carlo simulation are also available. These bounds are shown to be useful and computationally simple to obtain. Based on the proposed technique, one can readily find practical suboptimum IS parameters. Numerical results indicate that these bounding techniques are useful for IS simulations of linear and nonlinear communication systems with intersymbol interference in which bit error rate and IS estimation variances cannot be obtained readily using prior techniques.

On the likelihood of single-peaked preferences.

PubMed

Lackner, Marie-Louise; Lackner, Martin

2017-01-01

This paper contains an extensive combinatorial analysis of the single-peaked domain restriction and investigates the likelihood that an election is single-peaked. We provide a very general upper bound result for domain restrictions that can be defined by certain forbidden configurations. This upper bound implies that many domain restrictions (including the single-peaked restriction) are very unlikely to appear in a random election chosen according to the Impartial Culture assumption. For single-peaked elections, this upper bound can be refined and complemented by a lower bound that is asymptotically tight. In addition, we provide exact results for elections with few voters or candidates. Moreover, we consider the Pólya urn model and the Mallows model and obtain lower bounds showing that single-peakedness is considerably more likely to appear for certain parameterizations.

A tight upper bound for quadratic knapsack problems in grid-based wind farm layout optimization

NASA Astrophysics Data System (ADS)

Quan, Ning; Kim, Harrison M.

2018-03-01

The 0-1 quadratic knapsack problem (QKP) in wind farm layout optimization models possible turbine locations as nodes, and power loss due to wake effects between pairs of turbines as edges in a complete graph. The goal is to select up to a certain number of turbine locations such that the sum of selected node and edge coefficients is maximized. Finding the optimal solution to the QKP is difficult in general, but it is possible to obtain a tight upper bound on the QKP's optimal value which facilitates the use of heuristics to solve QKPs by giving a good estimate of the optimality gap of any feasible solution. This article applies an upper bound method that is especially well-suited to QKPs in wind farm layout optimization due to certain features of the formulation that reduce the computational complexity of calculating the upper bound. The usefulness of the upper bound was demonstrated by assessing the performance of the greedy algorithm for solving QKPs in wind farm layout optimization. The results show that the greedy algorithm produces good solutions within 4% of the optimal value for small to medium sized problems considered in this article.

Edge connectivity and the spectral gap of combinatorial and quantum graphs

NASA Astrophysics Data System (ADS)

Berkolaiko, Gregory; Kennedy, James B.; Kurasov, Pavel; Mugnolo, Delio

2017-09-01

We derive a number of upper and lower bounds for the first nontrivial eigenvalue of Laplacians on combinatorial and quantum graph in terms of the edge connectivity, i.e. the minimal number of edges which need to be removed to make the graph disconnected. On combinatorial graphs, one of the bounds corresponds to a well-known inequality of Fiedler, of which we give a new variational proof. On quantum graphs, the corresponding bound generalizes a recent result of Band and Lévy. All proofs are general enough to yield corresponding estimates for the p-Laplacian and allow us to identify the minimizers. Based on the Betti number of the graph, we also derive upper and lower bounds on all eigenvalues which are ‘asymptotically correct’, i.e. agree with the Weyl asymptotics for the eigenvalues of the quantum graph. In particular, the lower bounds improve the bounds of Friedlander on any given graph for all but finitely many eigenvalues, while the upper bounds improve recent results of Ariturk. Our estimates are also used to derive bounds on the eigenvalues of the normalized Laplacian matrix that improve known bounds of spectral graph theory.

On the role of entailment patterns and scalar implicatures in the processing of numerals

PubMed Central

Panizza, Daniele; Chierchia, Gennaro; Clifton, Charles

2009-01-01

There has been much debate, in both the linguistics and the psycholinguistics literature, concerning numbers and the interpretation of number denoting determiners ('numerals'). Such debate concerns, in particular, the nature and distribution of upper-bounded ('at-least') interpretations vs. lower-bounded ('exact') construals. In the present paper we show that the interpretation and processing of numerals are affected by the entailment properties of the context in which they occur. Experiment 1 established off-line preferences using a questionnaire. Experiment 2 investigated the processing issue through an eye tracking experiment using a silent reading task. Our results show that the upper-bounded interpretation of numerals occurs more often in an upward entailing context than in a downward entailing context. Reading times of the numeral itself were longer when it was embedded in an upward entailing context than when it was not, indicating that processing resources were required when the context triggered an upper-bounded interpretation. However, reading of a following context that required an upper-bounded interpretation triggered more regressions towards the numeral when it had occurred in a downward entailing context than in an upward entailing one. Such findings show that speakers' interpretation and processing of numerals is systematically affected by the polarity of the sentence in which they occur, and support the hypothesis that the upper-bounded interpretation of numerals is due to a scalar implicature. PMID:20161494

The Upper and Lower Bounds of the Prediction Accuracies of Ensemble Methods for Binary Classification

PubMed Central

Wang, Xueyi; Davidson, Nicholas J.

2011-01-01

Ensemble methods have been widely used to improve prediction accuracy over individual classifiers. In this paper, we achieve a few results about the prediction accuracies of ensemble methods for binary classification that are missed or misinterpreted in previous literature. First we show the upper and lower bounds of the prediction accuracies (i.e. the best and worst possible prediction accuracies) of ensemble methods. Next we show that an ensemble method can achieve > 0.5 prediction accuracy, while individual classifiers have < 0.5 prediction accuracies. Furthermore, for individual classifiers with different prediction accuracies, the average of the individual accuracies determines the upper and lower bounds. We perform two experiments to verify the results and show that it is hard to achieve the upper and lower bounds accuracies by random individual classifiers and better algorithms need to be developed. PMID:21853162

Upper bound of abutment scour in laboratory and field data

USGS Publications Warehouse

Benedict, Stephen

2016-01-01

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a field investigation of abutment scour in South Carolina and used those data to develop envelope curves that define the upper bound of abutment scour. To expand on this previous work, an additional cooperative investigation was initiated to combine the South Carolina data with abutment scour data from other sources and evaluate upper bound patterns with this larger data set. To facilitate this analysis, 446 laboratory and 331 field measurements of abutment scour were compiled into a digital database. This extensive database was used to evaluate the South Carolina abutment scour envelope curves and to develop additional envelope curves that reflected the upper bound of abutment scour depth for the laboratory and field data. The envelope curves provide simple but useful supplementary tools for assessing the potential maximum abutment scour depth in the field setting.

Lower bounds on the violation of the monogamy inequality for quantum correlation measures

NASA Astrophysics Data System (ADS)

Kumar, Asutosh; Dhar, Himadri Shekhar

2016-06-01

In multiparty quantum systems, the monogamy inequality proposes an upper bound on the distribution of bipartite quantum correlation between a single party and each of the remaining parties in the system, in terms of the amount of quantum correlation shared by that party with the rest of the system taken as a whole. However, it is well known that not all quantum correlation measures universally satisfy the monogamy inequality. In this work, we aim at determining the nontrivial value by which the monogamy inequality can be violated by a quantum correlation measure. Using an information-theoretic complementarity relation between the normalized purity and quantum correlation in any given multiparty state, we obtain a nontrivial lower bound on the negative monogamy score for the quantum correlation measure. In particular, for the three-qubit states the lower bound is equal to the negative von Neumann entropy of the single qubit reduced density matrix. We analytically examine the tightness of the derived lower bound for certain n -qubit quantum states. Further, we report numerical results of the same for monogamy violating correlation measures using Haar uniformly generated three-qubit states.

A Collaborative 20 Questions Model for Target Search with Human-Machine Interaction

DTIC Science & Technology

2013-05-01

optimal policies for entropy loss,” Journal of Applied Probability, vol. 49, pp. 114–136, 2012. [2] R. Castro and R. Nowak, “ Active learning and...vol. 10, pp. 223231, 1974. [8] R. Castro, Active Learning and Adaptive Sampling for Non- parametric Inference, Ph.D. thesis, Rice University, August...2007. [9] R. Castro and R. D. Nowak, “Upper and lower bounds for active learning ,” in 44th Annual Allerton Conference on Communica- tion, Control and Computing, 2006.

Physical Uncertainty Bounds (PUB)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaughan, Diane Elizabeth; Preston, Dean L.

2015-03-19

This paper introduces and motivates the need for a new methodology for determining upper bounds on the uncertainties in simulations of engineered systems due to limited fidelity in the composite continuum-level physics models needed to simulate the systems. We show that traditional uncertainty quantification methods provide, at best, a lower bound on this uncertainty. We propose to obtain bounds on the simulation uncertainties by first determining bounds on the physical quantities or processes relevant to system performance. By bounding these physics processes, as opposed to carrying out statistical analyses of the parameter sets of specific physics models or simply switchingmore » out the available physics models, one can obtain upper bounds on the uncertainties in simulated quantities of interest.« less

Perturbative unitarity constraints on gauge portals

NASA Astrophysics Data System (ADS)

El Hedri, Sonia; Shepherd, William; Walker, Devin G. E.

2017-12-01

Dark matter that was once in thermal equilibrium with the Standard Model is generally prohibited from obtaining all of its mass from the electroweak phase transition. This implies a new scale of physics and mediator particles to facilitate dark matter annihilation. In this work, we focus on dark matter that annihilates through a generic gauge boson portal. We show how partial wave unitarity places upper bounds on the dark gauge boson, dark Higgs and dark matter masses. Outside of well-defined fine-tuned regions, we find an upper bound of 9 TeV for the dark matter mass when the dark Higgs and dark gauge bosons both facilitate the dark matter annihilations. In this scenario, the upper bound on the dark Higgs and dark gauge boson masses are 10 TeV and 16 TeV, respectively. When only the dark gauge boson facilitates dark matter annihilations, we find an upper bound of 3 TeV and 6 TeV for the dark matter and dark gauge boson, respectively. Overall, using the gauge portal as a template, we describe a method to not only place upper bounds on the dark matter mass but also on the new particles with Standard Model quantum numbers. We briefly discuss the reach of future accelerator, direct and indirect detection experiments for this class of models.

Non-singular and cyclic universe from the modified GUP

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salah, Maha; Hammad, Fayçal; Faizal, Mir

In this paper, we investigate the effects of a new version of the generalized uncertainty principle (modified GUP) on the dynamics of the Universe. As the modified GUP will modify the relation between the entropy and area of the apparent horizon, it will also deform the Friedmann equations within Jacobson's approach. We explicitly find these deformed Friedmann equations governing the modified GUP-corrected dynamics of such a Universe. It is shown that the modified GUP-deformed Jacobson's approach implies an upper bound for the density of such a Universe. The Big Bang singularity can therefore also be avoided using the modified GUP-correctionsmore » to horizons' thermodynamics. In fact, we are able to analyze the pre Big Bang state of the Universe. Furthermore, the equations imply that the expansion of the Universe will come to a halt and then will immediately be followed by a contracting phase. When the equations are extrapolated beyond the maximum rate of contraction, a cyclic Universe scenario emerges.« less

Non-singular and cyclic universe from the modified GUP

NASA Astrophysics Data System (ADS)

Salah, Maha; Hammad, Fayçal; Faizal, Mir; Farag Ali, Ahmed

2017-02-01

In this paper, we investigate the effects of a new version of the generalized uncertainty principle (modified GUP) on the dynamics of the Universe. As the modified GUP will modify the relation between the entropy and area of the apparent horizon, it will also deform the Friedmann equations within Jacobson's approach. We explicitly find these deformed Friedmann equations governing the modified GUP-corrected dynamics of such a Universe. It is shown that the modified GUP-deformed Jacobson's approach implies an upper bound for the density of such a Universe. The Big Bang singularity can therefore also be avoided using the modified GUP-corrections to horizons' thermodynamics. In fact, we are able to analyze the pre Big Bang state of the Universe. Furthermore, the equations imply that the expansion of the Universe will come to a halt and then will immediately be followed by a contracting phase. When the equations are extrapolated beyond the maximum rate of contraction, a cyclic Universe scenario emerges.

Mathematics of gravitational lensing: multiple imaging and magnification

NASA Astrophysics Data System (ADS)

Petters, A. O.; Werner, M. C.

2010-09-01

The mathematical theory of gravitational lensing has revealed many generic and global properties. Beginning with multiple imaging, we review Morse-theoretic image counting formulas and lower bound results, and complex-algebraic upper bounds in the case of single and multiple lens planes. We discuss recent advances in the mathematics of stochastic lensing, discussing a general formula for the global expected number of minimum lensed images as well as asymptotic formulas for the probability densities of the microlensing random time delay functions, random lensing maps, and random shear, and an asymptotic expression for the global expected number of micro-minima. Multiple imaging in optical geometry and a spacetime setting are treated. We review global magnification relation results for model-dependent scenarios and cover recent developments on universal local magnification relations for higher order caustics.

Universality of quantum gravity corrections.

PubMed

Das, Saurya; Vagenas, Elias C

2008-11-28

We show that the existence of a minimum measurable length and the related generalized uncertainty principle (GUP), predicted by theories of quantum gravity, influence all quantum Hamiltonians. Thus, they predict quantum gravity corrections to various quantum phenomena. We compute such corrections to the Lamb shift, the Landau levels, and the tunneling current in a scanning tunneling microscope. We show that these corrections can be interpreted in two ways: (a) either that they are exceedingly small, beyond the reach of current experiments, or (b) that they predict upper bounds on the quantum gravity parameter in the GUP, compatible with experiments at the electroweak scale. Thus, more accurate measurements in the future should either be able to test these predictions, or further tighten the above bounds and predict an intermediate length scale between the electroweak and the Planck scale.

Reflections on conformal spectra

DOE PAGES

Kim, Hyungrok; Kravchuk, Petr; Ooguri, Hirosi

2016-04-29

Here, we use modular invariance and crossing symmetry of conformal field theory to reveal approximate reflection symmetries in the spectral decompositions of the partition function in two dimensions in the limit of large central charge and of the four-point function in any dimension in the limit of large scaling dimensions Δ 0 of external operators. We use these symmetries to motivate universal upper bounds on the spectrum and the operator product expansion coefficients, which we then derive by independent techniques. Some of the bounds for four-point functions are valid for finite Δ 0 as well as for large Δ 0.more » We discuss a similar symmetry in a large spacetime dimension limit. Finally, we comment on the analogue of the Cardy formula and sparse light spectrum condition for the four-point function.« less

Universal optimal hole-doping concentration in single-layer high-temperature cuprate superconductors

NASA Astrophysics Data System (ADS)

Honma, T.; Hor, P. H.

2006-09-01

We argue that in cuprate physics there are two types, hole content per CuO2 plane (Ppl) and the corresponding hole content per unit volume (P3D), of hole-doping concentrations for addressing physical properties that are two dimensional (2D) and three dimensional (3D) in nature, respectively. We find that the superconducting transition temperature (Tc) varies systematically with P3D as a superconducting 'dome' with a universal optimal hole-doping concentration of P3Dopt = 1.6 × 1021 cm-3 for single-layer high-temperature superconductors. We suggest that P3Dopt determines the upper bound of the electronic energy of underdoped single-layer high-Tc cuprates.

Eigenvalues of the Wentzell-Laplace operator and of the fourth order Steklov problems

NASA Astrophysics Data System (ADS)

Xia, Changyu; Wang, Qiaoling

2018-05-01

We prove a sharp upper bound and a lower bound for the first nonzero eigenvalue of the Wentzell-Laplace operator on compact manifolds with boundary and an isoperimetric inequality for the same eigenvalue in the case where the manifold is a bounded domain in a Euclidean space. We study some fourth order Steklov problems and obtain isoperimetric upper bound for the first eigenvalue of them. We also find all the eigenvalues and eigenfunctions for two kind of fourth order Steklov problems on a Euclidean ball.

SAS and SPSS macros to calculate standardized Cronbach's alpha using the upper bound of the phi coefficient for dichotomous items.

PubMed

Sun, Wei; Chou, Chih-Ping; Stacy, Alan W; Ma, Huiyan; Unger, Jennifer; Gallaher, Peggy

2007-02-01

Cronbach's a is widely used in social science research to estimate the internal consistency of reliability of a measurement scale. However, when items are not strictly parallel, the Cronbach's a coefficient provides a lower-bound estimate of true reliability, and this estimate may be further biased downward when items are dichotomous. The estimation of standardized Cronbach's a for a scale with dichotomous items can be improved by using the upper bound of coefficient phi. SAS and SPSS macros have been developed in this article to obtain standardized Cronbach's a via this method. The simulation analysis showed that Cronbach's a from upper-bound phi might be appropriate for estimating the real reliability when standardized Cronbach's a is problematic.

The Problem of Limited Inter-rater Agreement in Modelling Music Similarity

PubMed Central

Flexer, Arthur; Grill, Thomas

2016-01-01

One of the central goals of Music Information Retrieval (MIR) is the quantification of similarity between or within pieces of music. These quantitative relations should mirror the human perception of music similarity, which is however highly subjective with low inter-rater agreement. Unfortunately this principal problem has been given little attention in MIR so far. Since it is not meaningful to have computational models that go beyond the level of human agreement, these levels of inter-rater agreement present a natural upper bound for any algorithmic approach. We will illustrate this fundamental problem in the evaluation of MIR systems using results from two typical application scenarios: (i) modelling of music similarity between pieces of music; (ii) music structure analysis within pieces of music. For both applications, we derive upper bounds of performance which are due to the limited inter-rater agreement. We compare these upper bounds to the performance of state-of-the-art MIR systems and show how the upper bounds prevent further progress in developing better MIR systems. PMID:28190932

Evidence for a bound on the lifetime of de Sitter space

NASA Astrophysics Data System (ADS)

Freivogel, Ben; Lippert, Matthew

2008-12-01

Recent work has suggested a surprising new upper bound on the lifetime of de Sitter vacua in string theory. The bound is parametrically longer than the Hubble time but parametrically shorter than the recurrence time. We investigate whether the bound is satisfied in a particular class of de Sitter solutions, the KKLT vacua. Despite the freedom to make the supersymmetry breaking scale exponentially small, which naively would lead to extremely stable vacua, we find that the lifetime is always less than about exp(1022) Hubble times, in agreement with the proposed bound. This result, however, is contingent on several estimates and assumptions; in particular, we rely on a conjectural upper bound on the Euler number of the Calabi-Yau fourfolds used in KKLT compactifications.

Upper bound on the efficiency of certain nonimaging concentrators in the physical-optics model

NASA Astrophysics Data System (ADS)

Welford, W. T.; Winston, R.

1982-09-01

Upper bounds on the performance of nonimaging concentrators are obtained within the framework of scalar-wave theory by using a simple approach to avoid complex calculations on multiple phase fronts. The approach consists in treating a theoretically perfect image-forming device and postulating that no non-image-forming concentrator can have a better performance than such an ideal image-forming system. The performance of such a system can be calculated according to wave theory, and this will provide, in accordance with the postulate, upper bounds on the performance of nonimaging systems. The method is demonstrated for a two-dimensional compound parabolic concentrator.

LHC phenomenology of SO(10) models with Yukawa unification

NASA Astrophysics Data System (ADS)

Anandakrishnan, Archana; Bryant, B. Charles; Raby, Stuart; Wingerter, Akın

2013-10-01

In this paper we study an SO(10) SUSY GUT with Yukawa unification for the third generation. We perform a global χ2 analysis given to obtain the GUT boundary conditions consistent with 11 low-energy observables, including the top, bottom and tau masses. We assume a universal mass, m16, for squarks and sleptons and a universal gaugino mass, M1/2. We then analyze the phenomenological consequences for the LHC for 15 benchmark models with fixed m16=20TeV and with varying values of the gluino mass. The goal of the present work is to (i) evaluate the lower bound on the gluino mass in our model coming from the most recent published data of CMS and (ii) to compare this bound with similar bounds obtained by CMS using simplified models. The bottom line is that the bounds coming from the same-sign dilepton analysis are comparable for our model and the simplified model studied assuming B(g˜→tt¯χ˜10)=100%. However the bounds coming from the purely hadronic analyses for our model are 10%-20% lower than obtained for the simplified models. This is due to the fact that for our models the branching ratio for the decay g˜→gχ˜1,20 is significant. Thus there are significantly fewer b-jets. We find a lower bound on the gluino mass in our models with Mg˜≳1000GeV. Finally, there is a theoretical upper bound on the gluino mass which increases with the value of m16. For m16≤30TeV, the gluino mass satisfies Mg˜≤2.8TeV at 90% C.L. Thus, unless we further increase the amount of fine-tuning, we expect gluinos to be discovered at LHC 14.

Lower and upper bounds for entanglement of Rényi-α entropy.

PubMed

Song, Wei; Chen, Lin; Cao, Zhuo-Liang

2016-12-23

Entanglement Rényi-α entropy is an entanglement measure. It reduces to the standard entanglement of formation when α tends to 1. We derive analytical lower and upper bounds for the entanglement Rényi-α entropy of arbitrary dimensional bipartite quantum systems. We also demonstrate the application our bound for some concrete examples. Moreover, we establish the relation between entanglement Rényi-α entropy and some other entanglement measures.

Global a priori estimates for the inhomogeneous Landau equation with moderately soft potentials

NASA Astrophysics Data System (ADS)

Cameron, Stephen; Silvestre, Luis; Snelson, Stanley

2018-05-01

We establish a priori upper bounds for solutions to the spatially inhomogeneous Landau equation in the case of moderately soft potentials, with arbitrary initial data, under the assumption that mass, energy and entropy densities stay under control. Our pointwise estimates decay polynomially in the velocity variable. We also show that if the initial data satisfies a Gaussian upper bound, this bound is propagated for all positive times.

Global solutions of restricted open-shell Hartree-Fock theory from semidefinite programming with applications to strongly correlated quantum systems.

PubMed

Veeraraghavan, Srikant; Mazziotti, David A

2014-03-28

We present a density matrix approach for computing global solutions of restricted open-shell Hartree-Fock theory, based on semidefinite programming (SDP), that gives upper and lower bounds on the Hartree-Fock energy of quantum systems. While wave function approaches to Hartree-Fock theory yield an upper bound to the Hartree-Fock energy, we derive a semidefinite relaxation of Hartree-Fock theory that yields a rigorous lower bound on the Hartree-Fock energy. We also develop an upper-bound algorithm in which Hartree-Fock theory is cast as a SDP with a nonconvex constraint on the rank of the matrix variable. Equality of the upper- and lower-bound energies guarantees that the computed solution is the globally optimal solution of Hartree-Fock theory. The work extends a previously presented method for closed-shell systems [S. Veeraraghavan and D. A. Mazziotti, Phys. Rev. A 89, 010502-R (2014)]. For strongly correlated systems the SDP approach provides an alternative to the locally optimized Hartree-Fock energies and densities with a certificate of global optimality. Applications are made to the potential energy curves of C2, CN, Cr2, and NO2.

Perturbative unitarity constraints on gauge portals

DOE PAGES

El Hedri, Sonia; Shepherd, William; Walker, Devin G. E.

2017-10-03

Dark matter that was once in thermal equilibrium with the Standard Model is generally prohibited from obtaining all of its mass from the electroweak phase transition. This implies a new scale of physics and mediator particles to facilitate dark matter annihilation. In this work, we focus on dark matter that annihilates through a generic gauge boson portal. We show how partial wave unitarity places upper bounds on the dark gauge boson, dark Higgs and dark matter masses. Outside of well-defined fine-tuned regions, we find an upper bound of 9 TeV for the dark matter mass when the dark Higgs andmore » dark gauge bosons both facilitate the dark matter annihilations. In this scenario, the upper bound on the dark Higgs and dark gauge boson masses are 10 TeV and 16 TeV, respectively. When only the dark gauge boson facilitates dark matter annihilations, we find an upper bound of 3 TeV and 6 TeV for the dark matter and dark gauge boson, respectively. Overall, using the gauge portal as a template, we describe a method to not only place upper bounds on the dark matter mass but also on the new particles with Standard Model quantum numbers. Here, we briefly discuss the reach of future accelerator, direct and indirect detection experiments for this class of models.« less

Perturbative unitarity constraints on gauge portals

DOE Office of Scientific and Technical Information (OSTI.GOV)

El Hedri, Sonia; Shepherd, William; Walker, Devin G. E.

Dark matter that was once in thermal equilibrium with the Standard Model is generally prohibited from obtaining all of its mass from the electroweak phase transition. This implies a new scale of physics and mediator particles to facilitate dark matter annihilation. In this work, we focus on dark matter that annihilates through a generic gauge boson portal. We show how partial wave unitarity places upper bounds on the dark gauge boson, dark Higgs and dark matter masses. Outside of well-defined fine-tuned regions, we find an upper bound of 9 TeV for the dark matter mass when the dark Higgs andmore » dark gauge bosons both facilitate the dark matter annihilations. In this scenario, the upper bound on the dark Higgs and dark gauge boson masses are 10 TeV and 16 TeV, respectively. When only the dark gauge boson facilitates dark matter annihilations, we find an upper bound of 3 TeV and 6 TeV for the dark matter and dark gauge boson, respectively. Overall, using the gauge portal as a template, we describe a method to not only place upper bounds on the dark matter mass but also on the new particles with Standard Model quantum numbers. Here, we briefly discuss the reach of future accelerator, direct and indirect detection experiments for this class of models.« less

Noisy metrology: a saturable lower bound on quantum Fisher information

NASA Astrophysics Data System (ADS)

Yousefjani, R.; Salimi, S.; Khorashad, A. S.

2017-06-01

In order to provide a guaranteed precision and a more accurate judgement about the true value of the Cramér-Rao bound and its scaling behavior, an upper bound (equivalently a lower bound on the quantum Fisher information) for precision of estimation is introduced. Unlike the bounds previously introduced in the literature, the upper bound is saturable and yields a practical instruction to estimate the parameter through preparing the optimal initial state and optimal measurement. The bound is based on the underling dynamics, and its calculation is straightforward and requires only the matrix representation of the quantum maps responsible for encoding the parameter. This allows us to apply the bound to open quantum systems whose dynamics are described by either semigroup or non-semigroup maps. Reliability and efficiency of the method to predict the ultimate precision limit are demonstrated by three main examples.

Standard Deviation for Small Samples

ERIC Educational Resources Information Center

Joarder, Anwar H.; Latif, Raja M.

2006-01-01

Neater representations for variance are given for small sample sizes, especially for 3 and 4. With these representations, variance can be calculated without a calculator if sample sizes are small and observations are integers, and an upper bound for the standard deviation is immediate. Accessible proofs of lower and upper bounds are presented for…

Finite-error metrological bounds on multiparameter Hamiltonian estimation

NASA Astrophysics Data System (ADS)

Kura, Naoto; Ueda, Masahito

2018-01-01

Estimation of multiple parameters in an unknown Hamiltonian is investigated. We present upper and lower bounds on the time required to complete the estimation within a prescribed error tolerance δ . The lower bound is given on the basis of the Cramér-Rao inequality, where the quantum Fisher information is bounded by the squared evolution time. The upper bound is obtained by an explicit construction of estimation procedures. By comparing the cases with different numbers of Hamiltonian channels, we also find that the few-channel procedure with adaptive feedback and the many-channel procedure with entanglement are equivalent in the sense that they require the same amount of time resource up to a constant factor.

Neutrino oscillations: what do we know about θ13

NASA Astrophysics Data System (ADS)

Ernst, David

2008-10-01

The phenomenon of neutrino oscillations is reviewed. A new analysis tool for the recent, more finely binned Super-K atmospheric data is outlined. This analysis incorporates the full three-neutrino oscillation probabilities, including the mixing angle θ13 to all orders, and a full three- neutrino treatment of the Earth's MSW effect. Combined with the K2K, MINOS, and CHOOZ data, the upper bound on θ13 is found to arise from the Super-K atmospheric data, while the lower bound arises from CHOOZ. This is caused by the linear in θ13 terms which are of particualr importance in the region L/E>10^4 m/MeV where the sub-dominant expansion is not convergent. In addition, the enhancement of θ12 by the Earth MSW effect is found to be important for this result. The best fit value of θ13 is found to be (statistically insignificantly) negative and given by θ13=-0.07^+0.18-0.11. In collaboration with Jesus Escamilla, Vanderbilt University and David Latimer, University of Kentucky.

Optimism in the face of uncertainty supported by a statistically-designed multi-armed bandit algorithm.

PubMed

Kamiura, Moto; Sano, Kohei

2017-10-01

The principle of optimism in the face of uncertainty is known as a heuristic in sequential decision-making problems. Overtaking method based on this principle is an effective algorithm to solve multi-armed bandit problems. It was defined by a set of some heuristic patterns of the formulation in the previous study. The objective of the present paper is to redefine the value functions of Overtaking method and to unify the formulation of them. The unified Overtaking method is associated with upper bounds of confidence intervals of expected rewards on statistics. The unification of the formulation enhances the universality of Overtaking method. Consequently we newly obtain Overtaking method for the exponentially distributed rewards, numerically analyze it, and show that it outperforms UCB algorithm on average. The present study suggests that the principle of optimism in the face of uncertainty should be regarded as the statistics-based consequence of the law of large numbers for the sample mean of rewards and estimation of upper bounds of expected rewards, rather than as a heuristic, in the context of multi-armed bandit problems. Copyright © 2017 Elsevier B.V. All rights reserved.

Superadiabatic Controlled Evolutions and Universal Quantum Computation.

PubMed

Santos, Alan C; Sarandy, Marcelo S

2015-10-29

Adiabatic state engineering is a powerful technique in quantum information and quantum control. However, its performance is limited by the adiabatic theorem of quantum mechanics. In this scenario, shortcuts to adiabaticity, such as provided by the superadiabatic theory, constitute a valuable tool to speed up the adiabatic quantum behavior. Here, we propose a superadiabatic route to implement universal quantum computation. Our method is based on the realization of piecewise controlled superadiabatic evolutions. Remarkably, they can be obtained by simple time-independent counter-diabatic Hamiltonians. In particular, we discuss the implementation of fast rotation gates and arbitrary n-qubit controlled gates, which can be used to design different sets of universal quantum gates. Concerning the energy cost of the superadiabatic implementation, we show that it is dictated by the quantum speed limit, providing an upper bound for the corresponding adiabatic counterparts.

Superadiabatic Controlled Evolutions and Universal Quantum Computation

PubMed Central

Santos, Alan C.; Sarandy, Marcelo S.

2015-01-01

Adiabatic state engineering is a powerful technique in quantum information and quantum control. However, its performance is limited by the adiabatic theorem of quantum mechanics. In this scenario, shortcuts to adiabaticity, such as provided by the superadiabatic theory, constitute a valuable tool to speed up the adiabatic quantum behavior. Here, we propose a superadiabatic route to implement universal quantum computation. Our method is based on the realization of piecewise controlled superadiabatic evolutions. Remarkably, they can be obtained by simple time-independent counter-diabatic Hamiltonians. In particular, we discuss the implementation of fast rotation gates and arbitrary n-qubit controlled gates, which can be used to design different sets of universal quantum gates. Concerning the energy cost of the superadiabatic implementation, we show that it is dictated by the quantum speed limit, providing an upper bound for the corresponding adiabatic counterparts. PMID:26511064

The covariant entropy conjecture and concordance cosmological models

NASA Astrophysics Data System (ADS)

He, Song; Zhang, Hongbao

2008-10-01

Recently a covariant entropy conjecture has been proposed for dynamical horizons. We apply this conjecture to concordance cosmological models, namely, those cosmological models filled with perfect fluids, in the presence of a positive cosmological constant. As a result, we find that this conjecture has a severe constraint power. Not only does this conjecture rule out those cosmological models disfavored by the anthropic principle, but also it imposes an upper bound 10-60 on the cosmological constant for our own universe, which thus provides an alternative macroscopic perspective for understanding the long-standing cosmological constant problem.

An Upper Bound on High Speed Satellite Collision Probability When Only One Object has Position Uncertainty Information

NASA Technical Reports Server (NTRS)

Frisbee, Joseph H., Jr.

2015-01-01

Upper bounds on high speed satellite collision probability, PC †, have been investigated. Previous methods assume an individual position error covariance matrix is available for each object. The two matrices being combined into a single, relative position error covariance matrix. Components of the combined error covariance are then varied to obtain a maximum PC. If error covariance information for only one of the two objects was available, either some default shape has been used or nothing could be done. An alternative is presented that uses the known covariance information along with a critical value of the missing covariance to obtain an approximate but potentially useful Pc upper bound.

Tri-critical behavior of the Blume-Emery-Griffiths model on a Kagomé lattice: Effective-field theory and Rigorous bounds

NASA Astrophysics Data System (ADS)

Santos, Jander P.; Sá Barreto, F. C.

2016-01-01

Spin correlation identities for the Blume-Emery-Griffiths model on Kagomé lattice are derived and combined with rigorous correlation inequalities lead to upper bounds on the critical temperature. From the spin correlation identities the mean field approximation and the effective field approximation results for the magnetization, the critical frontiers and the tricritical points are obtained. The rigorous upper bounds on the critical temperature improve over those effective-field type theories results.

Bounds for the Z-spectral radius of nonnegative tensors.

PubMed

He, Jun; Liu, Yan-Min; Ke, Hua; Tian, Jun-Kang; Li, Xiang

2016-01-01

In this paper, we have proposed some new upper bounds for the largest Z-eigenvalue of an irreducible weakly symmetric and nonnegative tensor, which improve the known upper bounds obtained in Chang et al. (Linear Algebra Appl 438:4166-4182, 2013), Song and Qi (SIAM J Matrix Anal Appl 34:1581-1595, 2013), He and Huang (Appl Math Lett 38:110-114, 2014), Li et al. (J Comput Anal Appl 483:182-199, 2015), He (J Comput Anal Appl 20:1290-1301, 2016).

Morphological representation of order-statistics filters.

PubMed

Charif-Chefchaouni, M; Schonfeld, D

1995-01-01

We propose a comprehensive theory for the morphological bounds on order-statistics filters (and their repeated iterations). Conditions are derived for morphological openings and closings to serve as bounds (lower and upper, respectively) on order-statistics filters (and their repeated iterations). Under various assumptions, morphological open-closings and close-openings are also shown to serve as (tighter) bounds (lower and upper, respectively) on iterations of order-statistics filters. Simulations of the application of the results presented to image restoration are finally provided.

The upper bound of Pier Scour defined by selected laboratory and field data

USGS Publications Warehouse

Benedict, Stephen; Caldwell, Andral W.

2015-01-01

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted several field investigations of pier scour in South Carolina (Benedict and Caldwell, 2006; Benedict and Caldwell, 2009) and used that data to develop envelope curves defining the upper bound of pier scour. To expand upon this previous work, an additional cooperative investigation was initiated to combine the South Carolina data with pier-scour data from other sources and evaluate the upper bound of pier scour with this larger data set. To facilitate this analysis, a literature review was made to identify potential sources of published pier-scour data, and selected data were compiled into a digital spreadsheet consisting of approximately 570 laboratory and 1,880 field measurements. These data encompass a wide range of laboratory and field conditions and represent field data from 24 states within the United States and six other countries. This extensive database was used to define the upper bound of pier-scour depth with respect to pier width encompassing the laboratory and field data. Pier width is a primary variable that influences pier-scour depth (Laursen and Toch, 1956; Melville and Coleman, 2000; Mueller and Wagner, 2005, Ettema et al. 2011, Arneson et al. 2012) and therefore, was used as the primary explanatory variable in developing the upper-bound envelope curve. The envelope curve provides a simple but useful tool for assessing the potential maximum pier-scour depth for pier widths of about 30 feet or less.

Bounds on the information rate of quantum-secret-sharing schemes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarvepalli, Pradeep

An important metric of the performance of a quantum-secret-sharing scheme is its information rate. Beyond the fact that the information rate is upper-bounded by one, very little is known in terms of bounds on the information rate of quantum-secret-sharing schemes. Furthermore, not every scheme can be realized with rate one. In this paper we derive upper bounds for the information rates of quantum-secret-sharing schemes. We show that there exist quantum access structures on n players for which the information rate cannot be better than O((log{sub 2}n)/n). These results are the quantum analogues of the bounds for classical-secret-sharing schemes proved bymore » Csirmaz.« less

The upper bound to the Relative Reporting Ratio—a measure of the impact of the violation of hidden assumptions underlying some disproportionality methods used in signal detection

PubMed Central

Van Holle, Lionel; Bauchau, Vincent

2014-01-01

Purpose For disproportionality measures based on the Relative Reporting Ratio (RRR) such as the Information Component (IC) and the Empirical Bayesian Geometrical Mean (EBGM), each product and event is assumed to represent a negligible fraction of the spontaneous report database (SRD). Here, we provide the tools for allowing signal detection experts to assess the consequence of the violation of this assumption on their specific SRD. Methods For each product–event pair (P–E), a worst-case scenario associated all the reported events-of-interest with the product of interest. The values of the RRR under this scenario were measured for different sets of stratification factors using the GlaxoSmithKline vaccines SRD. These values represent the RRR upper bound that RRR cannot exceed whatever the true strength of association. Results Depending on the choice of stratification factors, the RRR could not exceed an upper bound of 2 for up to 2.4% of the P–Es. For Engerix™, 23.4% of all reports in the SDR, the RRR could not exceed an upper bound of 2 for up to 13.8% of pairs. For the P–E Rotarix™-Intussusception, the choice of stratification factors impacted the upper bound to RRR: from 52.5 for an unstratified RRR to 2.0 for a fully stratified RRR. Conclusions The quantification of the upper bound can indicate whether measures such as EBGM, IC, or RRR can be used for SRD for which products or events represent a non-negligible fraction of the entire SRD. In addition, at the level of the product or P–E, it can also highlight detrimental impact of overstratification. © 2014 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd. PMID:24395594

Bounds of memory strength for power-law series.

PubMed

Guo, Fangjian; Yang, Dan; Yang, Zimo; Zhao, Zhi-Dan; Zhou, Tao

2017-05-01

Many time series produced by complex systems are empirically found to follow power-law distributions with different exponents α. By permuting the independently drawn samples from a power-law distribution, we present nontrivial bounds on the memory strength (first-order autocorrelation) as a function of α, which are markedly different from the ordinary ±1 bounds for Gaussian or uniform distributions. When 1<α≤3, as α grows bigger, the upper bound increases from 0 to +1 while the lower bound remains 0; when α>3, the upper bound remains +1 while the lower bound descends below 0. Theoretical bounds agree well with numerical simulations. Based on the posts on Twitter, ratings of MovieLens, calling records of the mobile operator Orange, and the browsing behavior of Taobao, we find that empirical power-law-distributed data produced by human activities obey such constraints. The present findings explain some observed constraints in bursty time series and scale-free networks and challenge the validity of measures such as autocorrelation and assortativity coefficient in heterogeneous systems.

Bounds of memory strength for power-law series

NASA Astrophysics Data System (ADS)

Guo, Fangjian; Yang, Dan; Yang, Zimo; Zhao, Zhi-Dan; Zhou, Tao

2017-05-01

Many time series produced by complex systems are empirically found to follow power-law distributions with different exponents α . By permuting the independently drawn samples from a power-law distribution, we present nontrivial bounds on the memory strength (first-order autocorrelation) as a function of α , which are markedly different from the ordinary ±1 bounds for Gaussian or uniform distributions. When 1 <α ≤3 , as α grows bigger, the upper bound increases from 0 to +1 while the lower bound remains 0; when α >3 , the upper bound remains +1 while the lower bound descends below 0. Theoretical bounds agree well with numerical simulations. Based on the posts on Twitter, ratings of MovieLens, calling records of the mobile operator Orange, and the browsing behavior of Taobao, we find that empirical power-law-distributed data produced by human activities obey such constraints. The present findings explain some observed constraints in bursty time series and scale-free networks and challenge the validity of measures such as autocorrelation and assortativity coefficient in heterogeneous systems.

Bound of dissipation on a plane Couette dynamo

NASA Astrophysics Data System (ADS)

Alboussière, Thierry

2009-06-01

Variational turbulence is among the few approaches providing rigorous results in turbulence. In addition, it addresses a question of direct practical interest, namely, the rate of energy dissipation. Unfortunately, only an upper bound is obtained as a larger functional space than the space of solutions to the Navier-Stokes equations is searched. Yet, in some cases, this upper bound is in good agreement with experimental results in terms of order of magnitude and power law of the imposed Reynolds number. In this paper, the variational approach to turbulence is extended to the case of dynamo action and an upper bound is obtained for the global dissipation rate (viscous and Ohmic). A simple plane Couette flow is investigated. For low magnetic Prandtl number Pm fluids, the upper bound of energy dissipation is that of classical turbulence (i.e., proportional to the cubic power of the shear velocity) for magnetic Reynolds numbers below Pm-1 and follows a steeper evolution for magnetic Reynolds numbers above Pm-1 (i.e., proportional to the shear velocity to the power of 4) in the case of electrically insulating walls. However, the effect of wall conductance is crucial: for a given value of wall conductance, there is a value for the magnetic Reynolds number above which energy dissipation cannot be bounded. This limiting magnetic Reynolds number is inversely proportional to the square root of the conductance of the wall. Implications in terms of energy dissipation in experimental and natural dynamos are discussed.

Limitations of the background field method applied to Rayleigh-Bénard convection

NASA Astrophysics Data System (ADS)

Nobili, Camilla; Otto, Felix

2017-09-01

We consider Rayleigh-Bénard convection as modeled by the Boussinesq equations, in the case of infinite Prandtl numbers and with no-slip boundary condition. There is a broad interest in bounds of the upwards heat flux, as given by the Nusselt number Nu, in terms of the forcing via the imposed temperature difference, as given by the Rayleigh number in the turbulent regime Ra ≫ 1 . In several studies, the background field method applied to the temperature field has been used to provide upper bounds on Nu in terms of Ra. In these applications, the background field method comes in the form of a variational problem where one optimizes a stratified temperature profile subject to a certain stability condition; the method is believed to capture the marginal stability of the boundary layer. The best available upper bound via this method is Nu ≲Ra/1 3 ( ln R a )/1 15 ; it proceeds via the construction of a stable temperature background profile that increases logarithmically in the bulk. In this paper, we show that the background temperature field method cannot provide a tighter upper bound in terms of the power of the logarithm. However, by another method, one does obtain the tighter upper bound Nu ≲ Ra /1 3 ( ln ln Ra ) /1 3 so that the result of this paper implies that the background temperature field method is unphysical in the sense that it cannot provide the optimal bound.

Upper-Bound Estimates Of SEU in CMOS

NASA Technical Reports Server (NTRS)

Edmonds, Larry D.

1990-01-01

Theory of single-event upsets (SEU) (changes in logic state caused by energetic charged subatomic particles) in complementary metal oxide/semiconductor (CMOS) logic devices extended to provide upper-bound estimates of rates of SEU when limited experimental information available and configuration and dimensions of SEU-sensitive regions of devices unknown. Based partly on chord-length-distribution method.

An upper bound on the second order asymptotic expansion for the quantum communication cost of state redistribution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Datta, Nilanjana, E-mail: n.datta@statslab.cam.ac.uk; Hsieh, Min-Hsiu, E-mail: Min-Hsiu.Hsieh@uts.edu.au; Oppenheim, Jonathan, E-mail: j.oppenheim@ucl.ac.uk

State redistribution is the protocol in which given an arbitrary tripartite quantum state, with two of the subsystems initially being with Alice and one being with Bob, the goal is for Alice to send one of her subsystems to Bob, possibly with the help of prior shared entanglement. We derive an upper bound on the second order asymptotic expansion for the quantum communication cost of achieving state redistribution with a given finite accuracy. In proving our result, we also obtain an upper bound on the quantum communication cost of this protocol in the one-shot setting, by using the protocol ofmore » coherent state merging as a primitive.« less

Improved bounds on the energy-minimizing strains in martensitic polycrystals

NASA Astrophysics Data System (ADS)

Peigney, Michaël

2016-07-01

This paper is concerned with the theoretical prediction of the energy-minimizing (or recoverable) strains in martensitic polycrystals, considering a nonlinear elasticity model of phase transformation at finite strains. The main results are some rigorous upper bounds on the set of energy-minimizing strains. Those bounds depend on the polycrystalline texture through the volume fractions of the different orientations. The simplest form of the bounds presented is obtained by combining recent results for single crystals with a homogenization approach proposed previously for martensitic polycrystals. However, the polycrystalline bound delivered by that procedure may fail to recover the monocrystalline bound in the homogeneous limit, as is demonstrated in this paper by considering an example related to tetragonal martensite. This motivates the development of a more detailed analysis, leading to improved polycrystalline bounds that are notably consistent with results for single crystals in the homogeneous limit. A two-orientation polycrystal of tetragonal martensite is studied as an illustration. In that case, analytical expressions of the upper bounds are derived and the results are compared with lower bounds obtained by considering laminate textures.

Solving Open Job-Shop Scheduling Problems by SAT Encoding

NASA Astrophysics Data System (ADS)

Koshimura, Miyuki; Nabeshima, Hidetomo; Fujita, Hiroshi; Hasegawa, Ryuzo

This paper tries to solve open Job-Shop Scheduling Problems (JSSP) by translating them into Boolean Satisfiability Testing Problems (SAT). The encoding method is essentially the same as the one proposed by Crawford and Baker. The open problems are ABZ8, ABZ9, YN1, YN2, YN3, and YN4. We proved that the best known upper bounds 678 of ABZ9 and 884 of YN1 are indeed optimal. We also improved the upper bound of YN2 and lower bounds of ABZ8, YN2, YN3 and YN4.

Upper and lower bounds for semi-Markov reliability models of reconfigurable systems

NASA Technical Reports Server (NTRS)

White, A. L.

1984-01-01

This paper determines the information required about system recovery to compute the reliability of a class of reconfigurable systems. Upper and lower bounds are derived for these systems. The class consists of those systems that satisfy five assumptions: the components fail independently at a low constant rate, fault occurrence and system reconfiguration are independent processes, the reliability model is semi-Markov, the recovery functions which describe system configuration have small means and variances, and the system is well designed. The bounds are easy to compute, and examples are included.

The Laughlin liquid in an external potential

NASA Astrophysics Data System (ADS)

Rougerie, Nicolas; Yngvason, Jakob

2018-04-01

We study natural perturbations of the Laughlin state arising from the effects of trapping and disorder. These are N-particle wave functions that have the form of a product of Laughlin states and analytic functions of the N variables. We derive an upper bound to the ground state energy in a confining external potential, matching exactly a recently derived lower bound in the large N limit. Irrespective of the shape of the confining potential, this sharp upper bound can be achieved through a modification of the Laughlin function by suitably arranged quasi-holes.

Determining Normal-Distribution Tolerance Bounds Graphically

NASA Technical Reports Server (NTRS)

Mezzacappa, M. A.

1983-01-01

Graphical method requires calculations and table lookup. Distribution established from only three points: mean upper and lower confidence bounds and lower confidence bound of standard deviation. Method requires only few calculations with simple equations. Graphical procedure establishes best-fit line for measured data and bounds for selected confidence level and any distribution percentile.

An evaluation of risk estimation procedures for mixtures of carcinogens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hwang, J.S.; Chen, J.J.

1999-12-01

The estimation of health risks from exposure to a mixture of chemical carcinogens is generally based on the combination of information from several available single compound studies. The current practice of directly summing the upper bound risk estimates of individual carcinogenic components as an upper bound on the total risk of a mixture is known to be generally too conservative. Gaylor and Chen (1996, Risk Analysis) proposed a simple procedure to compute an upper bound on the total risk using only the upper confidence limits and central risk estimates of individual carcinogens. The Gaylor-Chen procedure was derived based on anmore » underlying assumption of the normality for the distributions of individual risk estimates. IN this paper the authors evaluated the Gaylor-Chen approach in terms the coverages of the upper confidence limits on the true risks of individual carcinogens. In general, if the coverage probabilities for the individual carcinogens are all approximately equal to the nominal level, then the Gaylor-Chen approach should perform well. However, the Gaylor-Chen approach can be conservative or anti-conservative if some of all individual upper confidence limit estimates are conservative or anti-conservative.« less

Fluctuation Theorem for Many-Body Pure Quantum States.

PubMed

Iyoda, Eiki; Kaneko, Kazuya; Sagawa, Takahiro

2017-09-08

We prove the second law of thermodynamics and the nonequilibrium fluctuation theorem for pure quantum states. The entire system obeys reversible unitary dynamics, where the initial state of the heat bath is not the canonical distribution but is a single energy eigenstate that satisfies the eigenstate-thermalization hypothesis. Our result is mathematically rigorous and based on the Lieb-Robinson bound, which gives the upper bound of the velocity of information propagation in many-body quantum systems. The entanglement entropy of a subsystem is shown connected to thermodynamic heat, highlighting the foundation of the information-thermodynamics link. We confirmed our theory by numerical simulation of hard-core bosons, and observed dynamical crossover from thermal fluctuations to bare quantum fluctuations. Our result reveals a universal scenario that the second law emerges from quantum mechanics, and can be experimentally tested by artificial isolated quantum systems such as ultracold atoms.

Search for a gamma-ray line feature from a group of nearby galaxy clusters with Fermi LAT Pass 8 data

NASA Astrophysics Data System (ADS)

Liang, Yun-Feng; Shen, Zhao-Qiang; Li, Xiang; Fan, Yi-Zhong; Huang, Xiaoyuan; Lei, Shi-Jun; Feng, Lei; Liang, En-Wei; Chang, Jin

2016-05-01

Galaxy clusters are the largest gravitationally bound objects in the Universe and may be suitable targets for indirect dark matter searches. With 85 months of Fermi LAT Pass 8 publicly available data, we analyze the gamma-ray emission in the direction of 16 nearby galaxy clusters with an unbinned likelihood analysis. No statistically or globally significant γ -ray line feature is identified and a tentative line signal may present at ˜43 GeV . The 95% confidence level upper limits on the velocity-averaged cross section of dark matter particles annihilating into double γ rays (i.e., ⟨σ v ⟩χχ →γ γ) are derived. Unless very optimistic boost factors of dark matter annihilation in these galaxy clusters have been assumed, such constraints are much weaker than the bounds set by the Galactic γ -ray data.

Fluctuation Theorem for Many-Body Pure Quantum States

NASA Astrophysics Data System (ADS)

Iyoda, Eiki; Kaneko, Kazuya; Sagawa, Takahiro

2017-09-01

We prove the second law of thermodynamics and the nonequilibrium fluctuation theorem for pure quantum states. The entire system obeys reversible unitary dynamics, where the initial state of the heat bath is not the canonical distribution but is a single energy eigenstate that satisfies the eigenstate-thermalization hypothesis. Our result is mathematically rigorous and based on the Lieb-Robinson bound, which gives the upper bound of the velocity of information propagation in many-body quantum systems. The entanglement entropy of a subsystem is shown connected to thermodynamic heat, highlighting the foundation of the information-thermodynamics link. We confirmed our theory by numerical simulation of hard-core bosons, and observed dynamical crossover from thermal fluctuations to bare quantum fluctuations. Our result reveals a universal scenario that the second law emerges from quantum mechanics, and can be experimentally tested by artificial isolated quantum systems such as ultracold atoms.

The upper bound of abutment scour defined by selected laboratory and field data

USGS Publications Warehouse

Benedict, Stephen; Caldwell, Andral W.

2015-01-01

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a field investigation of abutment scour in South Carolina and used that data to develop envelope curves defining the upper bound of abutment scour. To expand upon this previous work, an additional cooperative investigation was initiated to combine the South Carolina data with abutment-scour data from other sources and evaluate the upper bound of abutment scour with the larger data set. To facilitate this analysis, a literature review was made to identify potential sources of published abutment-scour data, and selected data, consisting of 446 laboratory and 331 field measurements, were compiled for the analysis. These data encompassed a wide range of laboratory and field conditions and represent field data from 6 states within the United States. The data set was used to evaluate the South Carolina abutment-scour envelope curves. Additionally, the data were used to evaluate a dimensionless abutment-scour envelope curve developed by Melville (1992), highlighting the distinct difference in the upper bound for laboratory and field data. The envelope curves evaluated in this investigation provide simple but useful tools for assessing the potential maximum abutment-scour depth in the field setting.

Symmetry Parameter Constraints from a Lower Bound on Neutron-matter Energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tews, Ingo; Lattimer, James M.; Ohnishi, Akira

We propose the existence of a lower bound on the energy of pure neutron matter (PNM) on the basis of unitary-gas considerations. We discuss its justification from experimental studies of cold atoms as well as from theoretical studies of neutron matter. We demonstrate that this bound results in limits to the density-dependent symmetry energy, which is the difference between the energies of symmetric nuclear matter and PNM. In particular, this bound leads to a lower limit to the volume symmetry energy parameter S {sub 0}. In addition, for assumed values of S {sub 0} above this minimum, this bound impliesmore » both upper and lower limits to the symmetry energy slope parameter L , which describes the lowest-order density dependence of the symmetry energy. A lower bound on neutron-matter incompressibility is also obtained. These bounds are found to be consistent with both recent calculations of the energies of PNM and constraints from nuclear experiments. Our results are significant because several equations of state that are currently used in astrophysical simulations of supernovae and neutron star mergers, as well as in nuclear physics simulations of heavy-ion collisions, have symmetry energy parameters that violate these bounds. Furthermore, below the nuclear saturation density, the bound on neutron-matter energies leads to a lower limit to the density-dependent symmetry energy, which leads to upper limits to the nuclear surface symmetry parameter and the neutron-star crust–core boundary. We also obtain a lower limit to the neutron-skin thicknesses of neutron-rich nuclei. Above the nuclear saturation density, the bound on neutron-matter energies also leads to an upper limit to the symmetry energy, with implications for neutron-star cooling via the direct Urca process.« less

Computational experience with a parallel algorithm for tetrangle inequality bound smoothing.

PubMed

Rajan, K; Deo, N

1999-09-01

Determining molecular structure from interatomic distances is an important and challenging problem. Given a molecule with n atoms, lower and upper bounds on interatomic distances can usually be obtained only for a small subset of the 2(n(n-1)) atom pairs, using NMR. Given the bounds so obtained on the distances between some of the atom pairs, it is often useful to compute tighter bounds on all the 2(n(n-1)) pairwise distances. This process is referred to as bound smoothing. The initial lower and upper bounds for the pairwise distances not measured are usually assumed to be 0 and infinity. One method for bound smoothing is to use the limits imposed by the triangle inequality. The distance bounds so obtained can often be tightened further by applying the tetrangle inequality--the limits imposed on the six pairwise distances among a set of four atoms (instead of three for the triangle inequalities). The tetrangle inequality is expressed by the Cayley-Menger determinants. For every quadruple of atoms, each pass of the tetrangle inequality bound smoothing procedure finds upper and lower limits on each of the six distances in the quadruple. Applying the tetrangle inequalities to each of the (4n) quadruples requires O(n4) time. Here, we propose a parallel algorithm for bound smoothing employing the tetrangle inequality. Each pass of our algorithm requires O(n3 log n) time on a REW PRAM (Concurrent Read Exclusive Write Parallel Random Access Machine) with O(log(n)n) processors. An implementation of this parallel algorithm on the Intel Paragon XP/S and its performance are also discussed.

Symmetry Parameter Constraints from a Lower Bound on Neutron-matter Energy

NASA Astrophysics Data System (ADS)

Tews, Ingo; Lattimer, James M.; Ohnishi, Akira; Kolomeitsev, Evgeni E.

2017-10-01

We propose the existence of a lower bound on the energy of pure neutron matter (PNM) on the basis of unitary-gas considerations. We discuss its justification from experimental studies of cold atoms as well as from theoretical studies of neutron matter. We demonstrate that this bound results in limits to the density-dependent symmetry energy, which is the difference between the energies of symmetric nuclear matter and PNM. In particular, this bound leads to a lower limit to the volume symmetry energy parameter S 0. In addition, for assumed values of S 0 above this minimum, this bound implies both upper and lower limits to the symmetry energy slope parameter L ,which describes the lowest-order density dependence of the symmetry energy. A lower bound on neutron-matter incompressibility is also obtained. These bounds are found to be consistent with both recent calculations of the energies of PNM and constraints from nuclear experiments. Our results are significant because several equations of state that are currently used in astrophysical simulations of supernovae and neutron star mergers, as well as in nuclear physics simulations of heavy-ion collisions, have symmetry energy parameters that violate these bounds. Furthermore, below the nuclear saturation density, the bound on neutron-matter energies leads to a lower limit to the density-dependent symmetry energy, which leads to upper limits to the nuclear surface symmetry parameter and the neutron-star crust-core boundary. We also obtain a lower limit to the neutron-skin thicknesses of neutron-rich nuclei. Above the nuclear saturation density, the bound on neutron-matter energies also leads to an upper limit to the symmetry energy, with implications for neutron-star cooling via the direct Urca process.

Divergences and estimating tight bounds on Bayes error with applications to multivariate Gaussian copula and latent Gaussian copula

NASA Astrophysics Data System (ADS)

Thelen, Brian J.; Xique, Ismael J.; Burns, Joseph W.; Goley, G. Steven; Nolan, Adam R.; Benson, Jonathan W.

2017-04-01

In Bayesian decision theory, there has been a great amount of research into theoretical frameworks and information- theoretic quantities that can be used to provide lower and upper bounds for the Bayes error. These include well-known bounds such as Chernoff, Battacharrya, and J-divergence. Part of the challenge of utilizing these various metrics in practice is (i) whether they are "loose" or "tight" bounds, (ii) how they might be estimated via either parametric or non-parametric methods, and (iii) how accurate the estimates are for limited amounts of data. In general what is desired is a methodology for generating relatively tight lower and upper bounds, and then an approach to estimate these bounds efficiently from data. In this paper, we explore the so-called triangle divergence which has been around for a while, but was recently made more prominent in some recent research on non-parametric estimation of information metrics. Part of this work is motivated by applications for quantifying fundamental information content in SAR/LIDAR data, and to help in this, we have developed a flexible multivariate modeling framework based on multivariate Gaussian copula models which can be combined with the triangle divergence framework to quantify this information, and provide approximate bounds on Bayes error. In this paper we present an overview of the bounds, including those based on triangle divergence and verify that under a number of multivariate models, the upper and lower bounds derived from triangle divergence are significantly tighter than the other common bounds, and often times, dramatically so. We also propose some simple but effective means for computing the triangle divergence using Monte Carlo methods, and then discuss estimation of the triangle divergence from empirical data based on Gaussian Copula models.

Method for universal detection of two-photon polarization entanglement

NASA Astrophysics Data System (ADS)

Bartkiewicz, Karol; Horodecki, Paweł; Lemr, Karel; Miranowicz, Adam; Życzkowski, Karol

2015-03-01

Detecting and quantifying quantum entanglement of a given unknown state poses problems that are fundamentally important for quantum information processing. Surprisingly, no direct (i.e., without quantum tomography) universal experimental implementation of a necessary and sufficient test of entanglement has been designed even for a general two-qubit state. Here we propose an experimental method for detecting a collective universal witness, which is a necessary and sufficient test of two-photon polarization entanglement. It allows us to detect entanglement for any two-qubit mixed state and to establish tight upper and lower bounds on its amount. A different element of this method is the sequential character of its main components, which allows us to obtain relatively complicated information about quantum correlations with the help of simple linear-optical elements. As such, this proposal realizes a universal two-qubit entanglement test within the present state of the art of quantum optics. We show the optimality of our setup with respect to the minimal number of measured quantities.

Upper and lower bounds of ground-motion variabilities: implication for source properties

NASA Astrophysics Data System (ADS)

Cotton, Fabrice; Reddy-Kotha, Sreeram; Bora, Sanjay; Bindi, Dino

2017-04-01

One of the key challenges of seismology is to be able to analyse the physical factors that control earthquakes and ground-motion variabilities. Such analysis is particularly important to calibrate physics-based simulations and seismic hazard estimations at high frequencies. Within the framework of the development of ground-motion prediction equation (GMPE) developments, ground-motions residuals (differences between recorded ground motions and the values predicted by a GMPE) are computed. The exponential growth of seismological near-source records and modern GMPE analysis technics allow to partition these residuals into between- and a within-event components. In particular, the between-event term quantifies all those repeatable source effects (e.g. related to stress-drop or kappa-source variability) which have not been accounted by the magnitude-dependent term of the model. In this presentation, we first discuss the between-event variabilities computed both in the Fourier and Response Spectra domains, using recent high-quality global accelerometric datasets (e.g. NGA-west2, Resorce, Kiknet). These analysis lead to the assessment of upper bounds for the ground-motion variability. Then, we compare these upper bounds with lower bounds estimated by analysing seismic sequences which occurred on specific fault systems (e.g., located in Central Italy or in Japan). We show that the lower bounds of between-event variabilities are surprisingly large which indicates a large variability of earthquake dynamic properties even within the same fault system. Finally, these upper and lower bounds of ground-shaking variability are discussed in term of variability of earthquake physical properties (e.g., stress-drop and kappa_source).

Considerations on Estimating Upper Bounds of Neutron Doses Equivalents to Military Participants at Atmospheric Nuclear Tests

DTIC Science & Technology

2007-04-01

distribution is unlimited. April 2007 DTRAo1-03-C-0064 David C. Kocher Prepared by: SENES Oak Ridge, Inc. 102 Donner Drive Oak Ridge, TN 37830 REPORT...Donner Drive Oak Ridge, TN 37830 8. PERFORMlNGORGANIZATION REPORT NUMBER DTRA-TR-07-3 9. SPONSORTNG/MONTTORTNG AGENCY NAME(S) AND ADDRESS(ES) Defense...Greensboro Drive, I\\{lS E-5-5 Mclean, VAZZI02 Senes Oak Ridge, Inc. 102 Donner Drive Oak Ridge, TN 37830 Oak Ridge Associated Universities 210 Badger Avenue Oak Ridge, TN 37830 ATTN:Dr. Toohev DL-2

Advancing precision cosmology with 21 cm intensity mapping

NASA Astrophysics Data System (ADS)

Masui, Kiyoshi Wesley

In this thesis we make progress toward establishing the observational method of 21 cm intensity mapping as a sensitive and efficient method for mapping the large-scale structure of the Universe. In Part I we undertake theoretical studies to better understand the potential of intensity mapping. This includes forecasting the ability of intensity mapping experiments to constrain alternative explanations to dark energy for the Universe's accelerated expansion. We also considered how 21 cm observations of the neutral gas in the early Universe (after recombination but before reionization) could be used to detect primordial gravity waves, thus providing a window into cosmological inflation. Finally we showed that scientifically interesting measurements could in principle be performed using intensity mapping in the near term, using existing telescopes in pilot surveys or prototypes for larger dedicated surveys. Part II describes observational efforts to perform some of the first measurements using 21 cm intensity mapping. We develop a general data analysis pipeline for analyzing intensity mapping data from single dish radio telescopes. We then apply the pipeline to observations using the Green Bank Telescope. By cross-correlating the intensity mapping survey with a traditional galaxy redshift survey we put a lower bound on the amplitude of the 21 cm signal. The auto-correlation provides an upper bound on the signal amplitude and we thus constrain the signal from both above and below. This pilot survey represents a pioneering effort in establishing 21 cm intensity mapping as a probe of the Universe.

Odds of observing the multiverse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dahlen, A.

2010-03-15

Eternal inflation predicts that our observable universe lies within a bubble (or pocket universe) embedded in a volume of inflating space. The interior of the bubble undergoes inflation and standard cosmology, while the bubble walls expand outward and collide with other neighboring bubbles. The collisions provide either an opportunity to make a direct observation of the multiverse or, if they produce unacceptable anisotropy, a threat to inflationary theory. The probability of an observer in our bubble detecting the effects of collisions has an absolute upper bound set by the odds of being in the part of our bubble that liesmore » in the forward light cone of a collision; in the case of collisions with bubbles of identical vacua, this bound is given by the bubble nucleation rate times (H{sub O}/H{sub I}){sup 2}, where H{sub O} is the Hubble scale outside the bubbles and H{sub I} is the scale of the second round of inflation that occurs inside our bubble. Similar results were obtained by Freigovel et al. using a different method for the case of collisions with bubbles of much larger cosmological constant; here, it is shown to hold in the case of collisions with identical bubbles as well.« less

Complexity, Heuristic, and Search Analysis for the Games of Crossings and Epaminondas

DTIC Science & Technology

2014-03-27

research in Artifical Intelligence (Section 2.1) and why games are studied (Section 2.2). Section 2.3 discusses how games are played and solved. An...5 2.1 Games in Artificial Intelligence . . . . . . . . . . . . . . . . . . . . . . . . 5 2.2 Game Study...Artificial Intelligence UCT Upper Confidence Bounds applied to Trees HUCT Heuristic Guided UCT LOA Lines of Action UCB Upper Confidence Bound RAVE Rapid

The Estimation of the IRT Reliability Coefficient and Its Lower and Upper Bounds, with Comparisons to CTT Reliability Statistics

ERIC Educational Resources Information Center

Kim, Seonghoon; Feldt, Leonard S.

2010-01-01

The primary purpose of this study is to investigate the mathematical characteristics of the test reliability coefficient rho[subscript XX'] as a function of item response theory (IRT) parameters and present the lower and upper bounds of the coefficient. Another purpose is to examine relative performances of the IRT reliability statistics and two…

Multivariate Lipschitz optimization: Survey and computational comparison

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, P.; Gourdin, E.; Jaumard, B.

1994-12-31

Many methods have been proposed to minimize a multivariate Lipschitz function on a box. They pertain the three approaches: (i) reduction to the univariate case by projection (Pijavskii) or by using a space-filling curve (Strongin); (ii) construction and refinement of a single upper bounding function (Pijavskii, Mladineo, Mayne and Polak, Jaumard Hermann and Ribault, Wood...); (iii) branch and bound with local upper bounding functions (Galperin, Pint{acute e}r, Meewella and Mayne, the present authors). A survey is made, stressing similarities of algorithms, expressed when possible within a unified framework. Moreover, an extensive computational comparison is reported on.

Numerical and analytical bounds on threshold error rates for hypergraph-product codes

NASA Astrophysics Data System (ADS)

Kovalev, Alexey A.; Prabhakar, Sanjay; Dumer, Ilya; Pryadko, Leonid P.

2018-06-01

We study analytically and numerically decoding properties of finite-rate hypergraph-product quantum low density parity-check codes obtained from random (3,4)-regular Gallager codes, with a simple model of independent X and Z errors. Several nontrivial lower and upper bounds for the decodable region are constructed analytically by analyzing the properties of the homological difference, equal minus the logarithm of the maximum-likelihood decoding probability for a given syndrome. Numerical results include an upper bound for the decodable region from specific heat calculations in associated Ising models and a minimum-weight decoding threshold of approximately 7 % .

Computational micromechanics of woven composites

NASA Technical Reports Server (NTRS)

Hopkins, Dale A.; Saigal, Sunil; Zeng, Xiaogang

1991-01-01

The bounds on the equivalent elastic material properties of a composite are presently addressed by a unified energy approach which is valid for both unidirectional and 2D and 3D woven composites. The unit cell considered is assumed to consist, first, of the actual composite arrangement of the fibers and matrix material, and then, of an equivalent pseudohomogeneous material. Equating the strain energies due to the two arrangements yields an estimate of the upper bound for the material equivalent properties; successive increases in the order of displacement field that is assumed in the composite arrangement will successively produce improved upper bound estimates.

Upper bounds on the photon mass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Accioly, Antonio; Group of Field Theory from First Principles, Sao Paulo State University; Instituto de Fisica Teorica

2010-09-15

The effects of a nonzero photon rest mass can be incorporated into electromagnetism in a simple way using the Proca equations. In this vein, two interesting implications regarding the possible existence of a massive photon in nature, i.e., tiny alterations in the known values of both the anomalous magnetic moment of the electron and the gravitational deflection of electromagnetic radiation, are utilized to set upper limits on its mass. The bounds obtained are not as stringent as those recently found; nonetheless, they are comparable to other existing bounds and bring new elements to the issue of restricting the photon mass.

Estimating the Richness of a Population When the Maximum Number of Classes Is Fixed: A Nonparametric Solution to an Archaeological Problem

PubMed Central

Eren, Metin I.; Chao, Anne; Hwang, Wen-Han; Colwell, Robert K.

2012-01-01

Background Estimating assemblage species or class richness from samples remains a challenging, but essential, goal. Though a variety of statistical tools for estimating species or class richness have been developed, they are all singly-bounded: assuming only a lower bound of species or classes. Nevertheless there are numerous situations, particularly in the cultural realm, where the maximum number of classes is fixed. For this reason, a new method is needed to estimate richness when both upper and lower bounds are known. Methodology/Principal Findings Here, we introduce a new method for estimating class richness: doubly-bounded confidence intervals (both lower and upper bounds are known). We specifically illustrate our new method using the Chao1 estimator, rarefaction, and extrapolation, although any estimator of asymptotic richness can be used in our method. Using a case study of Clovis stone tools from the North American Lower Great Lakes region, we demonstrate that singly-bounded richness estimators can yield confidence intervals with upper bound estimates larger than the possible maximum number of classes, while our new method provides estimates that make empirical sense. Conclusions/Significance Application of the new method for constructing doubly-bound richness estimates of Clovis stone tools permitted conclusions to be drawn that were not otherwise possible with singly-bounded richness estimates, namely, that Lower Great Lakes Clovis Paleoindians utilized a settlement pattern that was probably more logistical in nature than residential. However, our new method is not limited to archaeological applications. It can be applied to any set of data for which there is a fixed maximum number of classes, whether that be site occupancy models, commercial products (e.g. athletic shoes), or census information (e.g. nationality, religion, age, race). PMID:22666316

Upper bound on the Abelian gauge coupling from asymptotic safety

NASA Astrophysics Data System (ADS)

Eichhorn, Astrid; Versteegen, Fleur

2018-01-01

We explore the impact of asymptotically safe quantum gravity on the Abelian gauge coupling in a model including a charged scalar, confirming indications that asymptotically safe quantum fluctuations of gravity could trigger a power-law running towards a free fixed point for the gauge coupling above the Planck scale. Simultaneously, quantum gravity fluctuations balance against matter fluctuations to generate an interacting fixed point, which acts as a boundary of the basin of attraction of the free fixed point. This enforces an upper bound on the infrared value of the Abelian gauge coupling. In the regime of gravity couplings which in our approximation also allows for a prediction of the top quark and Higgs mass close to the experimental value [1], we obtain an upper bound approximately 35% above the infrared value of the hypercharge coupling in the Standard Model.

Limits of Gaussian fluctuations in the cosmic microwave background at 19.2 GHz

NASA Technical Reports Server (NTRS)

Boughn, S. P.; Cheng, E. S.; Cottingham, D. A.; Fixsen, D. J.

1992-01-01

The Northern Hemisphere data from the 19.2 GHz full sky survey are analyzed to place limits on the magnitude of Gaussian fluctuations in the cosmic microwave background implied by a variety of correlation functions. Included among the models tested are the monochromatic and Gaussian-shaped families, and those with power-law spectra for n values between -2 and 1. An upper bound is placed on the quadrupole anisotropy of Delta T/T less than 3.2 x 10 exp -5 rms, and an upper bound on scale-invariant (n = 1) fluctuations of a2 less than 4.5 x 10 exp -5 (95 percent confidence level). There is significant contamination of these data from Galactic emission, and improvement of the modeling of the Galaxy could yield a significant reduction of these upper bounds.

Limits on Gaussian fluctuations in the cosmic microwave background at 19.2 GHz

NASA Technical Reports Server (NTRS)

Boughn, S. P.; Cheng, E. S.; Cottingham, D. A.; Fixsen, D. J.

1991-01-01

The Northern Hemisphere data from the 19.2 GHz full sky survey are analyzed to place limits on the magnitude of Gaussian fluctuations in the cosmic microwave background implied by a variety of correlation functions. Included among the models tested are the monochromatic and Gaussian-shaped families, and those with power law spectra for n from -2 to 1. We place an upper bound on the quadrupole anisotropy of DeltaT/T less than 3.2 x 10 exp -5 rms, and an upper bound on scale-invariant (n = 1) fluctuations of a2 less than 4.5 x 10 exp -5 (95 percent confidence level). There is significant contamination of these data from Galactic emission, and improvement of our modeling of the Galaxy could yield a significant reduction of these upper bounds.

Limits on diffuse fluxes of high energy extraterrestrial neutrinos with the AMANDA-B10 detector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahrens, J.; Bai, X.; Barwick, S.W.

2003-03-11

Data from the AMANDA-B10 detector taken during the austral winter of 1997 have been searched for a diffuse flux of high energy extraterrestrial muon-neutrinos, as predicted from, e.g., the sum of all active galaxies in the universe. This search yielded no excess events above those expected from the background atmospheric neutrinos, leading to upper limits on the extraterrestrial neutrino flux. For an assumed E{sup -2} spectrum, a 90 percent classical confidence level upper limit has been placed at a level E{sup 2} Phi(E) = 8.4 x 10{sup -7} GeV cm{sup -2} s{sup -1}1 sr{sup -1} (for a predominant neutrino energymore » range 6-1000 TeV) which is the most restrictive bound placed by any neutrino detector. When specific predicted spectral forms are considered, it is found that some are excluded.« less

Upper Bound on Diffusivity

NASA Astrophysics Data System (ADS)

Hartman, Thomas; Hartnoll, Sean A.; Mahajan, Raghu

2017-10-01

The linear growth of operators in local quantum systems leads to an effective light cone even if the system is nonrelativistic. We show that the consistency of diffusive transport with this light cone places an upper bound on the diffusivity: D ≲v2τeq. The operator growth velocity v defines the light cone, and τeq is the local equilibration time scale, beyond which the dynamics of conserved densities is diffusive. We verify that the bound is obeyed in various weakly and strongly interacting theories. In holographic models, this bound establishes a relation between the hydrodynamic and leading nonhydrodynamic quasinormal modes of planar black holes. Our bound relates transport data—including the electrical resistivity and the shear viscosity—to the local equilibration time, even in the absence of a quasiparticle description. In this way, the bound sheds light on the observed T -linear resistivity of many unconventional metals, the shear viscosity of the quark-gluon plasma, and the spin transport of unitary fermions.

Backstepping Design of Adaptive Neural Fault-Tolerant Control for MIMO Nonlinear Systems.

PubMed

Gao, Hui; Song, Yongduan; Wen, Changyun

In this paper, an adaptive controller is developed for a class of multi-input and multioutput nonlinear systems with neural networks (NNs) used as a modeling tool. It is shown that all the signals in the closed-loop system with the proposed adaptive neural controller are globally uniformly bounded for any external input in . In our control design, the upper bound of the NN modeling error and the gains of external disturbance are characterized by unknown upper bounds, which is more rational to establish the stability in the adaptive NN control. Filter-based modification terms are used in the update laws of unknown parameters to improve the transient performance. Finally, fault-tolerant control is developed to accommodate actuator failure. An illustrative example applying the adaptive controller to control a rigid robot arm shows the validation of the proposed controller.In this paper, an adaptive controller is developed for a class of multi-input and multioutput nonlinear systems with neural networks (NNs) used as a modeling tool. It is shown that all the signals in the closed-loop system with the proposed adaptive neural controller are globally uniformly bounded for any external input in . In our control design, the upper bound of the NN modeling error and the gains of external disturbance are characterized by unknown upper bounds, which is more rational to establish the stability in the adaptive NN control. Filter-based modification terms are used in the update laws of unknown parameters to improve the transient performance. Finally, fault-tolerant control is developed to accommodate actuator failure. An illustrative example applying the adaptive controller to control a rigid robot arm shows the validation of the proposed controller.

Length bounds for connecting discharges in triggered lightning subsequent strokes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Idone, V.P.

1990-11-20

Highly time resolved streak recordings from nine subsequent strokes in four triggered flashes have been examined for evidence of the occurrence of upward connecting discharges. These photographic recordings were obtained with superior spatial and temporal resolution (0.3 m and 0.5 {lambda}s) and were examined with a video image analysis system to help delineate the separate leader and return stroke image tracks. Unfortunately, a definitive determination of the occurrence of connecting discharges in these strokes could not be made. The data did allow various determinations of an upper bound length for any possible connecting discharge in each stroke. Under the simplestmore » analysis approach possible, an 'absolute' upper bound set of lengths was measured that ranged from 12 to 27 m with a mean of 19 m; two other more involved analyses yielded arguably better upper bound estimates of 8-18 m and 7-26 m with means of 19 m; two other more involved analyses yielded arguably better upper bound estimates of 8-18 m and 7-26 m with means of 12 and 13 m, respectively. An additional set of low time-resolution telephoto recordings of the lowest few meters of channel revealed six strokes in these flashes with one or more upward unconnected channels originating from the lightning rod tip. The maximum length of unconnected channel seen in each of these strokes ranged from 0.2 to 1.6 m with a mean of 0.7 m. This latter set of observations is interpreted as indirect evidence that connecting discharges did occur in these strokes and that the lower bound for their length is about 1 m.« less

Risk assessment and monitoring programme of nitrates through vegetables in the Region of Valencia (Spain).

PubMed

Quijano, Leyre; Yusà, Vicent; Font, Guillermina; McAllister, Claudia; Torres, Concepción; Pardo, Olga

2017-02-01

This study was carried out to determine current levels of nitrate in vegetables marketed in the Region of Valencia (Spain) and to estimate the toxicological risk associated with their intake. A total of 533 samples of seven vegetable species were studied. Nitrate levels were derived from the Valencia Region monitoring programme carried out from 2009 to 2013 and food consumption levels were taken from the first Valencia Food Consumption Survey, conducted in 2010. The exposure was estimated using a probabilistic approach and two scenarios were assumed for left-censored data: the lower-bound scenario, in which unquantified results (below the limit of quantification) were set to zero and the upper-bound scenario, in which unquantified results were set to the limit of quantification value. The exposure of the Valencia consumers to nitrate through the consumption of vegetable products appears to be relatively low. In the adult population (16-95 years) the P99.9 was 3.13 mg kg -1 body weight day -1 and 3.15 mg kg -1 body weight day -1 in the lower bound and upper bound scenario, respectively. On the other hand, for young people (6-15 years) the P99.9 of the exposure was 4.20 mg kg -1 body weight day -1 and 4.40 mg kg -1 body weight day -1 in the lower bound and upper bound scenario, respectively. The risk characterisation indicates that, under the upper bound scenario, 0.79% of adults and 1.39% of young people can exceed the Acceptable Daily Intake of nitrate. This percentage could join the vegetable extreme consumers (such as vegetarians) of vegetables. Overall, the estimated exposures to nitrate from vegetables are unlikely to result in appreciable health risks. Copyright © 2016 Elsevier Ltd. All rights reserved.

On the upper bound in the Bohm sheath criterion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kotelnikov, I. A., E-mail: I.A.Kotelnikov@inp.nsk.su; Skovorodin, D. I., E-mail: D.I.Skovorodin@inp.nsk.su

2016-02-15

The question is discussed about the existence of an upper bound in the Bohm sheath criterion, according to which the Debye sheath at the interface between plasma and a negatively charged electrode is stable only if the ion flow velocity in plasma exceeds the ion sound velocity. It is stated that, with an exception of some artificial ionization models, the Bohm sheath criterion is satisfied as an equality at the lower bound and the ion flow velocity is equal to the speed of sound. In the one-dimensional theory, a supersonic flow appears in an unrealistic model of a localized ionmore » source the size of which is less than the Debye length; however, supersonic flows seem to be possible in the two- and three-dimensional cases. In the available numerical codes used to simulate charged particle sources with a plasma emitter, the presence of the upper bound in the Bohm sheath criterion is not supposed; however, the correspondence with experimental data is usually achieved if the ion flow velocity in plasma is close to the ion sound velocity.« less

Computer search for binary cyclic UEP codes of odd length up to 65

NASA Technical Reports Server (NTRS)

Lin, Mao-Chao; Lin, Chi-Chang; Lin, Shu

1990-01-01

Using an exhaustive computation, the unequal error protection capabilities of all binary cyclic codes of odd length up to 65 that have minimum distances at least 3 are found. For those codes that can only have upper bounds on their unequal error protection capabilities computed, an analytic method developed by Dynkin and Togonidze (1976) is used to show that the upper bounds meet the exact unequal error protection capabilities.

The direct reaction field hamiltonian: Analysis of the dispersion term and application to the water dimer

NASA Astrophysics Data System (ADS)

Thole, B. T.; Van Duijnen, P. Th.

1982-10-01

The induction and dispersion terms obtained from quantum-mechanical calculations with a direct reaction field hamiltonian are compared to second order perturbation theory expressions. The dispersion term is shown to give an upper bound which is a generalization of Alexander's upper bound. The model is illustrated by a calculation on the interactions in the water dimer. The long range Coulomb, induction and dispersion interactions are reasonably reproduced.

On the Kirchhoff Index of Graphs

NASA Astrophysics Data System (ADS)

Das, Kinkar C.

2013-09-01

Let G be a connected graph of order n with Laplacian eigenvalues μ1 ≥ μ2 ≥ ... ≥ μn-1 > mn = 0. The Kirchhoff index of G is defined as [xxx] In this paper. we give lower and upper bounds on Kf of graphs in terms on n, number of edges, maximum degree, and number of spanning trees. Moreover, we present lower and upper bounds on the Nordhaus-Gaddum-type result for the Kirchhoff index.

Upper bound of pier scour in laboratory and field data

USGS Publications Warehouse

Benedict, Stephen; Caldwell, Andral W.

2016-01-01

The U.S. Geological Survey (USGS), in cooperation with the South Carolina Department of Transportation, conducted several field investigations of pier scour in South Carolina and used the data to develop envelope curves defining the upper bound of pier scour. To expand on this previous work, an additional cooperative investigation was initiated to combine the South Carolina data with pier scour data from other sources and to evaluate upper-bound relations with this larger data set. To facilitate this analysis, 569 laboratory and 1,858 field measurements of pier scour were compiled to form the 2014 USGS Pier Scour Database. This extensive database was used to develop an envelope curve for the potential maximum pier scour depth encompassing the laboratory and field data. The envelope curve provides a simple but useful tool for assessing the potential maximum pier scour depth for effective pier widths of about 30 ft or less.

Resilient filtering for time-varying stochastic coupling networks under the event-triggering scheduling

NASA Astrophysics Data System (ADS)

Wang, Fan; Liang, Jinling; Dobaie, Abdullah M.

2018-07-01

The resilient filtering problem is considered for a class of time-varying networks with stochastic coupling strengths. An event-triggered strategy is adopted to save the network resources by scheduling the signal transmission from the sensors to the filters based on certain prescribed rules. Moreover, the filter parameters to be designed are subject to gain perturbations. The primary aim of the addressed problem is to determine a resilient filter that ensures an acceptable filtering performance for the considered network with event-triggering scheduling. To handle such an issue, an upper bound on the estimation error variance is established for each node according to the stochastic analysis. Subsequently, the resilient filter is designed by locally minimizing the derived upper bound at each iteration. Moreover, rigorous analysis shows the monotonicity of the minimal upper bound regarding the triggering threshold. Finally, a simulation example is presented to show effectiveness of the established filter scheme.

Objects of Maximum Electromagnetic Chirality

NASA Astrophysics Data System (ADS)

Fernandez-Corbaton, Ivan; Fruhnert, Martin; Rockstuhl, Carsten

2016-07-01

We introduce a definition of the electromagnetic chirality of an object and show that it has an upper bound. Reciprocal objects attain the upper bound if and only if they are transparent for all the fields of one polarization handedness (helicity). Additionally, electromagnetic duality symmetry, i.e., helicity preservation upon interaction, turns out to be a necessary condition for reciprocal objects to attain the upper bound. We use these results to provide requirements for the design of such extremal objects. The requirements can be formulated as constraints on the polarizability tensors for dipolar objects or on the material constitutive relations for continuous media. We also outline two applications for objects of maximum electromagnetic chirality: a twofold resonantly enhanced and background-free circular dichroism measurement setup, and angle-independent helicity filtering glasses. Finally, we use the theoretically obtained requirements to guide the design of a specific structure, which we then analyze numerically and discuss its performance with respect to maximal electromagnetic chirality.

Exact lower and upper bounds on stationary moments in stochastic biochemical systems

NASA Astrophysics Data System (ADS)

Ghusinga, Khem Raj; Vargas-Garcia, Cesar A.; Lamperski, Andrew; Singh, Abhyudai

2017-08-01

In the stochastic description of biochemical reaction systems, the time evolution of statistical moments for species population counts is described by a linear dynamical system. However, except for some ideal cases (such as zero- and first-order reaction kinetics), the moment dynamics is underdetermined as lower-order moments depend upon higher-order moments. Here, we propose a novel method to find exact lower and upper bounds on stationary moments for a given arbitrary system of biochemical reactions. The method exploits the fact that statistical moments of any positive-valued random variable must satisfy some constraints that are compactly represented through the positive semidefiniteness of moment matrices. Our analysis shows that solving moment equations at steady state in conjunction with constraints on moment matrices provides exact lower and upper bounds on the moments. These results are illustrated by three different examples—the commonly used logistic growth model, stochastic gene expression with auto-regulation and an activator-repressor gene network motif. Interestingly, in all cases the accuracy of the bounds is shown to improve as moment equations are expanded to include higher-order moments. Our results provide avenues for development of approximation methods that provide explicit bounds on moments for nonlinear stochastic systems that are otherwise analytically intractable.

Upper bounds on the error probabilities and asymptotic error exponents in quantum multiple state discrimination

NASA Astrophysics Data System (ADS)

Audenaert, Koenraad M. R.; Mosonyi, Milán

2014-10-01

We consider the multiple hypothesis testing problem for symmetric quantum state discrimination between r given states σ1, …, σr. By splitting up the overall test into multiple binary tests in various ways we obtain a number of upper bounds on the optimal error probability in terms of the binary error probabilities. These upper bounds allow us to deduce various bounds on the asymptotic error rate, for which it has been hypothesized that it is given by the multi-hypothesis quantum Chernoff bound (or Chernoff divergence) C(σ1, …, σr), as recently introduced by Nussbaum and Szkoła in analogy with Salikhov's classical multi-hypothesis Chernoff bound. This quantity is defined as the minimum of the pairwise binary Chernoff divergences min _{j

Detecting the Stochastic Gravitational-Wave Background

NASA Astrophysics Data System (ADS)

Colacino, Carlo Nicola

2017-12-01

The stochastic gravitational-wave background (SGWB) is by far the most difficult source of gravitational radiation detect. At the same time, it is the most interesting and intriguing one. This book describes the initial detection of the SGWB and describes the underlying mathematics behind one of the most amazing discoveries of the 21st century. On the experimental side it would mean that interferometric gravitational wave detectors work even better than expected. On the observational side, such a detection could give us information about the very early Universe, information that could not be obtained otherwise. Even negative results and improved upper bounds could put constraints on many cosmological and particle physics models.

Quantum gravitational contributions to the cosmic microwave background anisotropy spectrum.

PubMed

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.

Differential Games of inf-sup Type and Isaacs Equations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaise, Hidehiro; Sheu, S.-J.

2005-06-15

Motivated by the work of Fleming, we provide a general framework to associate inf-sup type values with the Isaacs equations.We show that upper and lower bounds for the generators of inf-sup type are upper and lower Hamiltonians, respectively. In particular, the lower (resp. upper) bound corresponds to the progressive (resp. strictly progressive) strategy. By the Dynamic Programming Principle and identification of the generator, we can prove that the inf-sup type game is characterized as the unique viscosity solution of the Isaacs equation. We also discuss the Isaacs equation with a Hamiltonian of a convex combination between the lower and uppermore » Hamiltonians.« less

Universal bounds on current fluctuations.

PubMed

Pietzonka, Patrick; Barato, Andre C; Seifert, Udo

2016-05-01

For current fluctuations in nonequilibrium steady states of Markovian processes, we derive four different universal bounds valid beyond the Gaussian regime. Different variants of these bounds apply to either the entropy change or any individual current, e.g., the rate of substrate consumption in a chemical reaction or the electron current in an electronic device. The bounds vary with respect to their degree of universality and tightness. A universal parabolic bound on the generating function of an arbitrary current depends solely on the average entropy production. A second, stronger bound requires knowledge both of the thermodynamic forces that drive the system and of the topology of the network of states. These two bounds are conjectures based on extensive numerics. An exponential bound that depends only on the average entropy production and the average number of transitions per time is rigorously proved. This bound has no obvious relation to the parabolic bound but it is typically tighter further away from equilibrium. An asymptotic bound that depends on the specific transition rates and becomes tight for large fluctuations is also derived. This bound allows for the prediction of the asymptotic growth of the generating function. Even though our results are restricted to networks with a finite number of states, we show that the parabolic bound is also valid for three paradigmatic examples of driven diffusive systems for which the generating function can be calculated using the additivity principle. Our bounds provide a general class of constraints for nonequilibrium systems.

Tidal disruption of Periodic Comet Shoemaker-Levy 9 and a constraint on its mean density

NASA Technical Reports Server (NTRS)

Boss, Alan P.

1994-01-01

The apparent tidal disruption of Periodic Comet Shoemaker-Levy 9 (1993e) during a close encounter within approximately 1.62 planetary radii of Jupiter can be used along with theoretical models of tidal disruption to place an upper bound on the density of the predisruption body. Depending on the theoretical model used, these upper bounds range from rho(sub c) less than 0.702 +/- 0.080 g/cu cm for a simple analytical model calibrated by numerical smoothed particle hydrodynamics (SPH) simulations to rho(sub c) less than 1.50 +/- 0.17 g/cu cm for a detailed semianalytical model. The quoted uncertainties stem from an assumed uncertainty in the perijove radius. However, the uncertainty introduced by the different theoretical models is the major source of error; this uncertainty could be eliminated by future SPH simulations specialized to cometary disruptions, including the effects of initially prolate, spinning comets. If the SPH-based upper bound turns out to be most appropriate, it would be consistent with the predisruption body being a comet with a relatively low density and porous structure, as has been asserted previously based on observations of cometary outgassing. Regardless of which upper bound is preferable, the models all agree that the predisruption body could not have been a relatively high-density body, such as an asteroid with rho approximately = 2 g/cu cm.

Limit analysis of hollow spheres or spheroids with Hill orthotropic matrix

NASA Astrophysics Data System (ADS)

Pastor, Franck; Pastor, Joseph; Kondo, Djimedo

2012-03-01

Recent theoretical studies of the literature are concerned by the hollow sphere or spheroid (confocal) problems with orthotropic Hill type matrix. They have been developed in the framework of the limit analysis kinematical approach by using very simple trial velocity fields. The present Note provides, through numerical upper and lower bounds, a rigorous assessment of the approximate criteria derived in these theoretical works. To this end, existing static 3D codes for a von Mises matrix have been easily extended to the orthotropic case. Conversely, instead of the non-obvious extension of the existing kinematic codes, a new original mixed approach has been elaborated on the basis of the plane strain structure formulation earlier developed by F. Pastor (2007). Indeed, such a formulation does not need the expressions of the unit dissipated powers. Interestingly, it delivers a numerical code better conditioned and notably more rapid than the previous one, while preserving the rigorous upper bound character of the corresponding numerical results. The efficiency of the whole approach is first demonstrated through comparisons of the results to the analytical upper bounds of Benzerga and Besson (2001) or Monchiet et al. (2008) in the case of spherical voids in the Hill matrix. Moreover, we provide upper and lower bounds results for the hollow spheroid with the Hill matrix which are compared to those of Monchiet et al. (2008).

Data report for onshore-offshore wide-angle seismic recordings in the Bering-Chukchi Sea, Western Alaska and eastern Siberia

USGS Publications Warehouse

Brocher, Thomas M.; Allen, Richard M.; Stone, David B.; Wolf, Lorraine W.; Galloway, Brian K.

1995-01-01

This report presents fourteen deep-crustal wide-angle seismic reflection and refraction profiles recorded onland in western Alaska and eastern Siberia from marine air gun sources in the Bering-Chukchi Seas. During a 20-day period in August, 1994, the R/V Ewing acquired two long (a total of 3754 km) deep-crustal seismic-reflection profiles on the continental shelf of the Bering and Chukchi Seas, in a collaborative project between Stanford University and the United States Geological Survey (USGS). The Ewing's 137.7 liter (8355 cu. in.) air gun array was the source for both the multichannel reflection and the wide-angle seismic data. The Ewing, operated by the Lamont-Doherty Earth Observatory, steamed northward from Nunivak Island to Barrow, and returned, firing the air gun array at intervals of either 50 m or 75 m. About 37,700 air gun shots were fired along the northward directed Lines 1 and 2, and more than 40,000 air gun shots were fired along the southward directed Line 3. The USGS and the University of Alaska, Fairbanks (UAF), deployed an array of twelve 3-component REFTEK and PDAS recorders in western Alaska and eastern Siberia which continuously recorded the air gun signals fired during the northward bound Lines 1 and 2. Seven of these recorders also continuously recorded the southward bound Line 3. These wide-angle seismic data were acquired to: (1) image reflectors in the upper to lower crust, (2) determine crustal and upper mantle refraction velocities, and (3) provide important constraints on the geometry of the Moho along the seismic lines. In this report, we describe the land recording of wide-angle data conducted by the USGS and the UAF, describe in detail how the wide-angle REFTEK and PDAS data were reduced to common receiver gather seismic sections, and illustrate the wide-angle seismic data obtained by the REFTEKs and PDAS's. Air gun signals were observed to ranges in excess of 400 km, and crustal and upper /mantle refractions indicate substantial variation in the crustal thickness along the transect.

Spherically symmetric vacuum in covariant F (T )=T +α/2 T2+O (Tγ) gravity theory

NASA Astrophysics Data System (ADS)

DeBenedictis, Andrew; Ilijić, Saša

2016-12-01

Recently, a fully covariant version of the theory of F (T ) torsion gravity has been introduced by M. Kršśák and E. Saridakis [Classical Quantum Gravity 33, 115009 (2016)]. In covariant F (T ) gravity, the Schwarzschild solution is not a vacuum solution for F (T )≠T , and therefore determining the spherically symmetric vacuum is an important open problem. Within the covariant framework, we perturbatively solve the spherically symmetric vacuum gravitational equations around the Schwarzschild solution for the scenario with F (T )=T +(α /2 )T2 , representing the dominant terms in theories governed by Lagrangians analytic in the torsion scalar. From this, we compute the perihelion shift correction to solar system planetary orbits as well as perturbative gravitational effects near neutron stars. This allows us to set an upper bound on the magnitude of the coupling constant, α , which governs deviations from general relativity. We find the bound on this nonlinear torsion coupling constant by specifically considering the uncertainty in the perihelion shift of Mercury. We also analyze a bound from a similar comparison with the periastron orbit of the binary pulsar PSR J0045-7319 as an independent check for consistency. Setting bounds on the dominant nonlinear coupling is important in determining if other effects in the Solar System or greater universe could be attributable to nonlinear torsion.

Universal upper limit on inflation energy scale from cosmic magnetic field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujita, Tomohiro; Mukohyama, Shinji, E-mail: tomohiro.fujita@ipmu.jp, E-mail: shinji.mukohyama@ipmu.jp

2012-10-01

Recently observational lower bounds on the strength of cosmic magnetic fields were reported, based on γ-ray flux from distant blazars. If inflation is responsible for the generation of such magnetic fields then the inflation energy scale is bounded from above as ρ{sub inf}{sup 1/4} < 2.5 × 10{sup −7}M{sub Pl} × (B{sub obs}/10{sup −15}G){sup −2} in a wide class of inflationary magnetogenesis models, where B{sub obs} is the observed strength of cosmic magnetic fields. The tensor-to-scalar ratio is correspondingly constrained as r < 10{sup −19} × (B{sub obs}/10{sup −15}G){sup −8}. Therefore, if the reported strength B{sub obs} ≥ 10{sup −15}Gmore » is confirmed and if any signatures of gravitational waves from inflation are detected in the near future, then our result indicates some tensions between inflationary magnetogenesis and observations.« less

Thermal diffusivity and butterfly velocity in anisotropic Q-lattice models

NASA Astrophysics Data System (ADS)

Jeong, Hyun-Sik; Ahn, Yongjun; Ahn, Dujin; Niu, Chao; Li, Wei-Jia; Kim, Keun-Young

2018-01-01

We study a relation between the thermal diffusivity ( D T ) and two quantum chaotic properties, Lyapunov time (τ L ) and butterfly velocity ( v B ) in strongly correlated systems by using a holographic method. Recently, it was shown that E_i:={D}_{T,i}/({v}{^{B,i}}^2{τ}_L)(i=x,y) is universal in the sense that it is determined only by some scaling exponents of the IR metric in the low temperature limit regardless of the matter fields and ultraviolet data. Inspired by this observation, by analyzing the anisotropic IR scaling geometry carefully, we find the concrete expressions for E_i in terms of the critical dynamical exponents z i in each direction, E_i={z}_i/2({z}_i-1) . Furthermore, we find the lower bound of E_i is always 1 /2, which is not affected by anisotropy, contrary to the η/s case. However, there may be an upper bound determined by given fixed anisotropy.

Interacting dark energy: Dynamical system analysis

NASA Astrophysics Data System (ADS)

Golchin, Hanif; Jamali, Sara; Ebrahimi, Esmaeil

We investigate the impacts of interaction between dark matter (DM) and dark energy (DE) in the context of two DE models, holographic (HDE) and ghost dark energy (GDE). In fact, using the dynamical system analysis, we obtain the cosmological consequence of several interactions, considering all relevant component of universe, i.e. matter (dark and luminous), radiation and DE. Studying the phase space for all interactions in detail, we show the existence of unstable matter-dominated and stable DE-dominated phases. We also show that linear interactions suffer from the absence of standard radiation-dominated epoch. Interestingly, this failure resolved by adding the nonlinear interactions to the models. We find an upper bound for the value of the coupling constant of the interaction between DM and DE as b < 0.57in the case of holographic model, and b < 0.61 in the case of GDE model, to result in a cosmological viable matter-dominated epoch. More specifically, this bound is vital to satisfy instability and deceleration of matter-dominated epoch.

Bounds for the price of discrete arithmetic Asian options

NASA Astrophysics Data System (ADS)

Vanmaele, M.; Deelstra, G.; Liinev, J.; Dhaene, J.; Goovaerts, M. J.

2006-01-01

In this paper the pricing of European-style discrete arithmetic Asian options with fixed and floating strike is studied by deriving analytical lower and upper bounds. In our approach we use a general technique for deriving upper (and lower) bounds for stop-loss premiums of sums of dependent random variables, as explained in Kaas et al. (Ins. Math. Econom. 27 (2000) 151-168), and additionally, the ideas of Rogers and Shi (J. Appl. Probab. 32 (1995) 1077-1088) and of Nielsen and Sandmann (J. Financial Quant. Anal. 38(2) (2003) 449-473). We are able to create a unifying framework for European-style discrete arithmetic Asian options through these bounds, that generalizes several approaches in the literature as well as improves the existing results. We obtain analytical and easily computable bounds. The aim of the paper is to formulate an advice of the appropriate choice of the bounds given the parameters, investigate the effect of different conditioning variables and compare their efficiency numerically. Several sets of numerical results are included. We also discuss hedging using these bounds. Moreover, our methods are applicable to a wide range of (pricing) problems involving a sum of dependent random variables.

Coefficient of performance and its bounds with the figure of merit for a general refrigerator

NASA Astrophysics Data System (ADS)

Long, Rui; Liu, Wei

2015-02-01

A general refrigerator model with non-isothermal processes is studied. The coefficient of performance (COP) and its bounds at maximum χ figure of merit are obtained and analyzed. This model accounts for different heat capacities during the heat transfer processes. So, different kinds of refrigerator cycles can be considered. Under the constant heat capacity condition, the upper bound of the COP is the Curzon-Ahlborn (CA) coefficient of performance and is independent of the time durations of the heat exchanging processes. With the maximum χ criterion, in the refrigerator cycles, such as the reversed Brayton refrigerator cycle, the reversed Otto refrigerator cycle and the reversed Atkinson refrigerator cycle, where the heat capacity in the heat absorbing process is not less than that in the heat releasing process, their COPs are bounded by the CA coefficient of performance; otherwise, such as for the reversed Diesel refrigerator cycle, its COP can exceed the CA coefficient of performance. Furthermore, the general refined upper and lower bounds have been proposed.

Search for Chemically Bound Water in the Surface Layer of Mars Based on HEND/Mars Odyssey Data

NASA Technical Reports Server (NTRS)

Basilevsky, A. T.; Litvak, M. L.; Mitrofanov, I. G.; Boynton, W.; Saunders, R. S.

2003-01-01

This study is emphasized on search for signatures of chemically bound water in surface layer of Mars based on data acquired by High Energy Neutron Detector (HEND) which is part of the Mars Odyssey Gamma Ray Spectrometer (GRS). Fluxes of epithermal (probe the upper 1-2 m) and fast (the upper 20-30 cm) neutrons, considered in this work, were measured since mid February till mid June 2002. First analysis of this data set with emphasis of chemically bound water was made. Early publications of the GRS results reported low neutron flux at high latitudes, interpreted as signature of ground water ice, and in two low latitude areas: Arabia and SW of Olympus Mons (SWOM), interpreted as 'geographic variations in the amount of chemically and/or physically bound H2O and or OH...'. It is clear that surface materials of Mars do contain chemically bound water, but its amounts are poorly known and its geographic distribution was not analyzed.

Pre-Test Assessment of the Upper Bound of the Drag Coefficient Repeatability of a Wind Tunnel Model

NASA Technical Reports Server (NTRS)

Ulbrich, N.; L'Esperance, A.

2017-01-01

A new method is presented that computes a pre{test estimate of the upper bound of the drag coefficient repeatability of a wind tunnel model. This upper bound is a conservative estimate of the precision error of the drag coefficient. For clarity, precision error contributions associated with the measurement of the dynamic pressure are analyzed separately from those that are associated with the measurement of the aerodynamic loads. The upper bound is computed by using information about the model, the tunnel conditions, and the balance in combination with an estimate of the expected output variations as input. The model information consists of the reference area and an assumed angle of attack. The tunnel conditions are described by the Mach number and the total pressure or unit Reynolds number. The balance inputs are the partial derivatives of the axial and normal force with respect to all balance outputs. Finally, an empirical output variation of 1.0 microV/V is used to relate both random instrumentation and angle measurement errors to the precision error of the drag coefficient. Results of the analysis are reported by plotting the upper bound of the precision error versus the tunnel conditions. The analysis shows that the influence of the dynamic pressure measurement error on the precision error of the drag coefficient is often small when compared with the influence of errors that are associated with the load measurements. Consequently, the sensitivities of the axial and normal force gages of the balance have a significant influence on the overall magnitude of the drag coefficient's precision error. Therefore, results of the error analysis can be used for balance selection purposes as the drag prediction characteristics of balances of similar size and capacities can objectively be compared. Data from two wind tunnel models and three balances are used to illustrate the assessment of the precision error of the drag coefficient.

Circles-in-the-sky searches and observable cosmic topology in a flat universe

NASA Astrophysics Data System (ADS)

Mota, B.; Rebouças, M. J.; Tavakol, R.

2010-05-01

In a universe with a detectable nontrivial spatial topology, the last scattering surface contains pairs of matching circles with the same distribution of temperature fluctuations—the so-called circles-in-the-sky. Searches for nearly antipodal circles-in-the-sky in maps of cosmic microwave background radiation have so far been unsuccessful. This negative outcome, along with recent theoretical results concerning the detectability of nearly flat compact topologies, is sufficient to exclude a detectable nontrivial topology for most observers in very nearly flat positively and negatively curved universes, whose total matter-energy density satisfies 0<|Ωtot-1|≲10-5. Here, we investigate the consequences of these searches for observable nontrivial topologies if the Universe turns out to be exactly flat (Ωtot=1). We demonstrate that in this case, the conclusions deduced from such searches can be radically different. We show that, although there is no characteristic topological scale in the flat manifolds, for all multiply-connected orientable flat manifolds, it is possible to directly study the action of the holonomies in order to obtain a general upper bound on the angle that characterizes the deviation from antipodicity of pairs of matching circles associated with the shortest closed geodesic. This bound is valid for all observers and all possible values of the compactification length parameters. We also show that in a flat universe, there are observers for whom the circles-in-the-sky searches already undertaken are insufficient to exclude the possibility of a detectable nontrivial spatial topology. It is remarkable how such small variations in the spatial curvature of the Universe, which are effectively indistinguishable geometrically, can have such a drastic effect on the detectability of cosmic topology. Another important outcome of our results is that they offer a framework with which to make statistical inferences from future circles-in-the-sky searches on whether the Universe is exactly flat.

Improved Lower Bounds on the Price of Stability of Undirected Network Design Games

NASA Astrophysics Data System (ADS)

Bilò, Vittorio; Caragiannis, Ioannis; Fanelli, Angelo; Monaco, Gianpiero

Bounding the price of stability of undirected network design games with fair cost allocation is a challenging open problem in the Algorithmic Game Theory research agenda. Even though the generalization of such games in directed networks is well understood in terms of the price of stability (it is exactly H n , the n-th harmonic number, for games with n players), far less is known for network design games in undirected networks. The upper bound carries over to this case as well while the best known lower bound is 42/23 ≈ 1.826. For more restricted but interesting variants of such games such as broadcast and multicast games, sublogarithmic upper bounds are known while the best known lower bound is 12/7 ≈ 1.714. In the current paper, we improve the lower bounds as follows. We break the psychological barrier of 2 by showing that the price of stability of undirected network design games is at least 348/155 ≈ 2.245. Our proof uses a recursive construction of a network design game with a simple gadget as the main building block. For broadcast and multicast games, we present new lower bounds of 20/11 ≈ 1.818 and 1.862, respectively.

An analysis of the vertical structure equation for arbitrary thermal profiles

NASA Technical Reports Server (NTRS)

Cohn, Stephen E.; Dee, Dick P.

1989-01-01

The vertical structure equation is a singular Sturm-Liouville problem whose eigenfunctions describe the vertical dependence of the normal modes of the primitive equations linearized about a given thermal profile. The eigenvalues give the equivalent depths of the modes. The spectrum of the vertical structure equation and the appropriateness of various upper boundary conditions, both for arbitrary thermal profiles were studied. The results depend critically upon whether or not the thermal profile is such that the basic state atmosphere is bounded. In the case of a bounded atmosphere it is shown that the spectrum is always totally discrete, regardless of details of the thermal profile. For the barotropic equivalent depth, which corresponds to the lowest eigen value, upper and lower bounds which depend only on the surface temperature and the atmosphere height were obtained. All eigenfunctions are bounded, but always have unbounded first derivatives. It was proved that the commonly invoked upper boundary condition that vertical velocity must vanish as pressure tends to zero, as well as a number of alternative conditions, is well posed. It was concluded that the vertical structure equation always has a totally discrete spectrum under the assumptions implicit in the primitive equations.

An analysis of the vertical structure equation for arbitrary thermal profiles

NASA Technical Reports Server (NTRS)

Cohn, Stephen E.; Dee, Dick P.

1987-01-01

The vertical structure equation is a singular Sturm-Liouville problem whose eigenfunctions describe the vertical dependence of the normal modes of the primitive equations linearized about a given thermal profile. The eigenvalues give the equivalent depths of the modes. The spectrum of the vertical structure equation and the appropriateness of various upper boundary conditions, both for arbitrary thermal profiles were studied. The results depend critically upon whether or not the thermal profile is such that the basic state atmosphere is bounded. In the case of a bounded atmosphere it is shown that the spectrum is always totally discrete, regardless of details of the thermal profile. For the barotropic equivalent depth, which corresponds to the lowest eigen value, upper and lower bounds which depend only on the surface temperature and the atmosphere height were obtained. All eigenfunctions are bounded, but always have unbounded first derivatives. It was proved that the commonly invoked upper boundary condition that vertical velocity must vanish as pressure tends to zero, as well as a number of alternative conditions, is well posed. It was concluded that the vertical structure equation always has a totally discrete spectrum under the assumptions implicit in the primitive equations.

Ultimate energy density of observable cold baryonic matter.

PubMed

Lattimer, James M; Prakash, Madappa

2005-03-25

We demonstrate that the largest measured mass of a neutron star establishes an upper bound to the energy density of observable cold baryonic matter. An equation of state-independent expression satisfied by both normal neutron stars and self-bound quark matter stars is derived for the largest energy density of matter inside stars as a function of their masses. The largest observed mass sets the lowest upper limit to the density. Implications from existing and future neutron star mass measurements are discussed.

Generalized monogamy inequalities and upper bounds of negativity for multiqubit systems

NASA Astrophysics Data System (ADS)

Yang, Yanmin; Chen, Wei; Li, Gang; Zheng, Zhu-Jun

2018-01-01

In this paper, we present some generalized monogamy inequalities and upper bounds of negativity based on convex-roof extended negativity (CREN) and CREN of assistance (CRENOA). These monogamy relations are satisfied by the negativity of N -qubit quantum systems A B C1⋯CN -2 , under the partitions A B | C1⋯CN -2 and A B C1| C2⋯CN -2 . Furthermore, the W -class states are used to test these generalized monogamy inequalities.

Computing an upper bound on contact stress with surrogate duality

NASA Astrophysics Data System (ADS)

Xuan, Zhaocheng; Papadopoulos, Panayiotis

2016-07-01

We present a method for computing an upper bound on the contact stress of elastic bodies. The continuum model of elastic bodies with contact is first modeled as a constrained optimization problem by using finite elements. An explicit formulation of the total contact force, a fraction function with the numerator as a linear function and the denominator as a quadratic convex function, is derived with only the normalized nodal contact forces as the constrained variables in a standard simplex. Then two bounds are obtained for the sum of the nodal contact forces. The first is an explicit formulation of matrices of the finite element model, derived by maximizing the fraction function under the constraint that the sum of the normalized nodal contact forces is one. The second bound is solved by first maximizing the fraction function subject to the standard simplex and then using Dinkelbach's algorithm for fractional programming to find the maximum—since the fraction function is pseudo concave in a neighborhood of the solution. These two bounds are solved with the problem dimensions being only the number of contact nodes or node pairs, which are much smaller than the dimension for the original problem, namely, the number of degrees of freedom. Next, a scheme for constructing an upper bound on the contact stress is proposed that uses the bounds on the sum of the nodal contact forces obtained on a fine finite element mesh and the nodal contact forces obtained on a coarse finite element mesh, which are problems that can be solved at a lower computational cost. Finally, the proposed method is verified through some examples concerning both frictionless and frictional contact to demonstrate the method's feasibility, efficiency, and robustness.

Performance bounds on parallel self-initiating discrete-event

NASA Technical Reports Server (NTRS)

Nicol, David M.

1990-01-01

The use is considered of massively parallel architectures to execute discrete-event simulations of what is termed self-initiating models. A logical process in a self-initiating model schedules its own state re-evaluation times, independently of any other logical process, and sends its new state to other logical processes following the re-evaluation. The interest is in the effects of that communication on synchronization. The performance is considered of various synchronization protocols by deriving upper and lower bounds on optimal performance, upper bounds on Time Warp's performance, and lower bounds on the performance of a new conservative protocol. The analysis of Time Warp includes the overhead costs of state-saving and rollback. The analysis points out sufficient conditions for the conservative protocol to outperform Time Warp. The analysis also quantifies the sensitivity of performance to message fan-out, lookahead ability, and the probability distributions underlying the simulation.

Bounds on the Coupling of the Majoron to Light Neutrinos from Supernova Cooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farzan, Yasaman

2002-12-02

We explore the role of Majoron (J) emission in the supernova cooling process, as a source of upper bound on the neutrino-Majoron coupling. We show that the strongest upper bound on the coupling to {nu}{sub 3} comes from the {nu}{sub e}{nu}{sub e} {yields} J process in the core of a supernova. We also find bounds on diagonal couplings of the Majoron to {nu}{sub {mu}({tau})}{nu}{sub {mu}({tau})} and on off-diagonal {nu}{sub e}{nu}{sub {mu}({tau})} couplings in various regions of the parameter space. We discuss the evaluation of cross-section for four-particle interactions ({nu}{nu} {yields} JJ and {nu}J {yields} {nu}J). We show that these aremore » typically dominated by three-particle sub-processes and do not give new independent constraints.« less

A linear programming approach to max-sum problem: a review.

PubMed

Werner, Tomás

2007-07-01

The max-sum labeling problem, defined as maximizing a sum of binary (i.e., pairwise) functions of discrete variables, is a general NP-hard optimization problem with many applications, such as computing the MAP configuration of a Markov random field. We review a not widely known approach to the problem, developed by Ukrainian researchers Schlesinger et al. in 1976, and show how it contributes to recent results, most importantly, those on the convex combination of trees and tree-reweighted max-product. In particular, we review Schlesinger et al.'s upper bound on the max-sum criterion, its minimization by equivalent transformations, its relation to the constraint satisfaction problem, the fact that this minimization is dual to a linear programming relaxation of the original problem, and the three kinds of consistency necessary for optimality of the upper bound. We revisit problems with Boolean variables and supermodular problems. We describe two algorithms for decreasing the upper bound. We present an example application for structural image analysis.

Kernel K-Means Sampling for Nyström Approximation.

PubMed

He, Li; Zhang, Hong

2018-05-01

A fundamental problem in Nyström-based kernel matrix approximation is the sampling method by which training set is built. In this paper, we suggest to use kernel -means sampling, which is shown in our works to minimize the upper bound of a matrix approximation error. We first propose a unified kernel matrix approximation framework, which is able to describe most existing Nyström approximations under many popular kernels, including Gaussian kernel and polynomial kernel. We then show that, the matrix approximation error upper bound, in terms of the Frobenius norm, is equal to the -means error of data points in kernel space plus a constant. Thus, the -means centers of data in kernel space, or the kernel -means centers, are the optimal representative points with respect to the Frobenius norm error upper bound. Experimental results, with both Gaussian kernel and polynomial kernel, on real-world data sets and image segmentation tasks show the superiority of the proposed method over the state-of-the-art methods.

ϕ 3 theory with F4 flavor symmetry in 6 - 2 ɛ dimensions: 3-loop renormalization and conformal bootstrap

NASA Astrophysics Data System (ADS)

Pang, Yi; Rong, Junchen; Su, Ning

2016-12-01

We consider ϕ 3 theory in 6 - 2 ɛ with F 4 global symmetry. The beta function is calculated up to 3 loops, and a stable unitary IR fixed point is observed. The anomalous dimensions of operators quadratic or cubic in ϕ are also computed. We then employ conformal bootstrap technique to study the fixed point predicted from the perturbative approach. For each putative scaling dimension of ϕ (Δ ϕ ), we obtain the corresponding upper bound on the scaling dimension of the second lowest scalar primary in the 26 representation ( Δ 26 2nd ) which appears in the OPE of ϕ × ϕ. In D = 5 .95, we observe a sharp peak on the upper bound curve located at Δ ϕ equal to the value predicted by the 3-loop computation. In D = 5, we observe a weak kink on the upper bound curve at ( Δ ϕ , Δ 26 2nd ) = (1.6, 4).

Strong polygamy of quantum correlations in multi-party quantum systems

NASA Astrophysics Data System (ADS)

Kim, Jeong San

2014-10-01

We propose a new type of polygamy inequality for multi-party quantum entanglement. We first consider the possible amount of bipartite entanglement distributed between a fixed party and any subset of the rest parties in a multi-party quantum system. By using the summation of these distributed entanglements, we provide an upper bound of the distributed entanglement between a party and the rest in multi-party quantum systems. We then show that this upper bound also plays as a lower bound of the usual polygamy inequality, therefore the strong polygamy of multi-party quantum entanglement. For the case of multi-party pure states, we further show that the strong polygamy of entanglement implies the strong polygamy of quantum discord.

Optimal bounds and extremal trajectories for time averages in nonlinear dynamical systems

NASA Astrophysics Data System (ADS)

Tobasco, Ian; Goluskin, David; Doering, Charles R.

2018-02-01

For any quantity of interest in a system governed by ordinary differential equations, it is natural to seek the largest (or smallest) long-time average among solution trajectories, as well as the extremal trajectories themselves. Upper bounds on time averages can be proved a priori using auxiliary functions, the optimal choice of which is a convex optimization problem. We prove that the problems of finding maximal trajectories and minimal auxiliary functions are strongly dual. Thus, auxiliary functions provide arbitrarily sharp upper bounds on time averages. Moreover, any nearly minimal auxiliary function provides phase space volumes in which all nearly maximal trajectories are guaranteed to lie. For polynomial equations, auxiliary functions can be constructed by semidefinite programming, which we illustrate using the Lorenz system.

Semiclassical analysis of spectral singularities and their applications in optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mostafazadeh, Ali

2011-08-15

Motivated by possible applications of spectral singularities in optics, we develop a semiclassical method of computing spectral singularities. We use this method to examine the spectral singularities of a planar slab gain medium whose gain coefficient varies due to the exponential decay of the intensity of the pumping beam inside the medium. For both singly and doublypumped samples, we obtain universal upper bounds on the decay constant beyond which no lasing occurs. Furthermore, we show that the dependence of the wavelength of the spectral singularities on the value of the decay constant is extremely mild. This is an indication ofmore » the stability of optical spectral singularities.« less

Upper bounds on quantum uncertainty products and complexity measures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guerrero, Angel; Sanchez-Moreno, Pablo; Dehesa, Jesus S.

The position-momentum Shannon and Renyi uncertainty products of general quantum systems are shown to be bounded not only from below (through the known uncertainty relations), but also from above in terms of the Heisenberg-Kennard product . Moreover, the Cramer-Rao, Fisher-Shannon, and Lopez-Ruiz, Mancini, and Calbet shape measures of complexity (whose lower bounds have been recently found) are also bounded from above. The improvement of these bounds for systems subject to spherically symmetric potentials is also explicitly given. Finally, applications to hydrogenic and oscillator-like systems are done.

Minimum-error quantum distinguishability bounds from matrix monotone functions: A comment on 'Two-sided estimates of minimum-error distinguishability of mixed quantum states via generalized Holevo-Curlander bounds' [J. Math. Phys. 50, 032106 (2009)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tyson, Jon

2009-06-15

Matrix monotonicity is used to obtain upper bounds on minimum-error distinguishability of arbitrary ensembles of mixed quantum states. This generalizes one direction of a two-sided bound recently obtained by the author [J. Tyson, J. Math. Phys. 50, 032106 (2009)]. It is shown that the previously obtained special case has unique properties.

Bond additive modeling 10. Upper and lower bounds of bond incident degree indices of catacondensed fluoranthenes

NASA Astrophysics Data System (ADS)

Vukičević, Damir; Đurđević, Jelena

2011-10-01

Bond incident degree index is a descriptor that is calculated as the sum of the bond contributions such that each bond contribution depends solely on the degrees of its incident vertices (e.g. Randić index, Zagreb index, modified Zagreb index, variable Randić index, atom-bond connectivity index, augmented Zagreb index, sum-connectivity index, many Adriatic indices, and many variable Adriatic indices). In this Letter we find tight upper and lower bounds for bond incident degree index for catacondensed fluoranthenes with given number of hexagons.

Beating the photon-number-splitting attack in practical quantum cryptography.

PubMed

Wang, Xiang-Bin

2005-06-17

We propose an efficient method to verify the upper bound of the fraction of counts caused by multiphoton pulses in practical quantum key distribution using weak coherent light, given whatever type of Eve's action. The protocol simply uses two coherent states for the signal pulses and vacuum for the decoy pulse. Our verified upper bound is sufficiently tight for quantum key distribution with a very lossy channel, in both the asymptotic and nonasymptotic case. So far our protocol is the only decoy-state protocol that works efficiently for currently existing setups.

The local interstellar helium density - Corrected

NASA Technical Reports Server (NTRS)

Freeman, J.; Paresce, F.; Bowyer, S.

1979-01-01

An upper bound for the number density of neutral helium in the local interstellar medium of 0.004 + or - 0.0022 per cu cm was previously reported, based on extreme-ultraviolet telescope observations at 584 A made during the 1975 Apollo-Soyuz Test Project. A variety of evidence is found which indicates that the 584-A sensitivity of the instrument declined by a factor of 2 between the last laboratory calibration and the time of the measurements. The upper bound on the helium density is therefore revised to 0.0089 + or - 0.005 per cu cm.

Upper bound on three-tangles of reduced states of four-qubit pure states

NASA Astrophysics Data System (ADS)

Sharma, S. Shelly; Sharma, N. K.

2017-06-01

Closed formulas for upper bounds on three-tangles of three-qubit reduced states in terms of three-qubit-invariant polynomials of pure four-qubit states are obtained. Our results offer tighter constraints on total three-way entanglement of a given qubit with the rest of the system than those used by Regula et al. [Phys. Rev. Lett. 113, 110501 (2014), 10.1103/PhysRevLett.113.110501 and Phys. Rev. Lett. 116, 049902(E) (2016)], 10.1103/PhysRevLett.116.049902 to verify monogamy of four-qubit quantum entanglement.

A fresh look into the interacting dark matter scenario

NASA Astrophysics Data System (ADS)

Escudero, Miguel; Lopez-Honorez, Laura; Mena, Olga; Palomares-Ruiz, Sergio; Villanueva-Domingo, Pablo

2018-06-01

The elastic scattering between dark matter particles and radiation represents an attractive possibility to solve a number of discrepancies between observations and standard cold dark matter predictions, as the induced collisional damping would imply a suppression of small-scale structures. We consider this scenario and confront it with measurements of the ionization history of the Universe at several redshifts and with recent estimates of the counts of Milky Way satellite galaxies. We derive a conservative upper bound on the dark matter-photon elastic scattering cross section of σγ DM < 8 × 10‑10 σT (mDM/GeV) at 95% CL, about one order of magnitude tighter than previous constraints from satellite number counts. Due to the strong degeneracies with astrophysical parameters, the bound on the dark matter-photon scattering cross section derived here is driven by the estimate of the number of Milky Way satellite galaxies. Finally, we also argue that future 21 cm probes could help in disentangling among possible non-cold dark matter candidates, such as interacting and warm dark matter scenarios. Let us emphasize that bounds of similar magnitude to the ones obtained here could be also derived for models with dark matter-neutrino interactions and would be as constraining as the tightest limits on such scenarios.

Circuit bounds on stochastic transport in the Lorenz equations

NASA Astrophysics Data System (ADS)

Weady, Scott; Agarwal, Sahil; Wilen, Larry; Wettlaufer, J. S.

2018-07-01

In turbulent Rayleigh-Bénard convection one seeks the relationship between the heat transport, captured by the Nusselt number, and the temperature drop across the convecting layer, captured by the Rayleigh number. In experiments, one measures the Nusselt number for a given Rayleigh number, and the question of how close that value is to the maximal transport is a key prediction of variational fluid mechanics in the form of an upper bound. The Lorenz equations have traditionally been studied as a simplified model of turbulent Rayleigh-Bénard convection, and hence it is natural to investigate their upper bounds, which has previously been done numerically and analytically, but they are not as easily accessible in an experimental context. Here we describe a specially built circuit that is the experimental analogue of the Lorenz equations and compare its output to the recently determined upper bounds of the stochastic Lorenz equations [1]. The circuit is substantially more efficient than computational solutions, and hence we can more easily examine the system. Because of offsets that appear naturally in the circuit, we are motivated to study unique bifurcation phenomena that arise as a result. Namely, for a given Rayleigh number, we find a reentrant behavior of the transport on noise amplitude and this varies with Rayleigh number passing from the homoclinic to the Hopf bifurcation.

A fast algorithm for determining bounds and accurate approximate p-values of the rank product statistic for replicate experiments.

PubMed

Heskes, Tom; Eisinga, Rob; Breitling, Rainer

2014-11-21

The rank product method is a powerful statistical technique for identifying differentially expressed molecules in replicated experiments. A critical issue in molecule selection is accurate calculation of the p-value of the rank product statistic to adequately address multiple testing. Both exact calculation and permutation and gamma approximations have been proposed to determine molecule-level significance. These current approaches have serious drawbacks as they are either computationally burdensome or provide inaccurate estimates in the tail of the p-value distribution. We derive strict lower and upper bounds to the exact p-value along with an accurate approximation that can be used to assess the significance of the rank product statistic in a computationally fast manner. The bounds and the proposed approximation are shown to provide far better accuracy over existing approximate methods in determining tail probabilities, with the slightly conservative upper bound protecting against false positives. We illustrate the proposed method in the context of a recently published analysis on transcriptomic profiling performed in blood. We provide a method to determine upper bounds and accurate approximate p-values of the rank product statistic. The proposed algorithm provides an order of magnitude increase in throughput as compared with current approaches and offers the opportunity to explore new application domains with even larger multiple testing issue. The R code is published in one of the Additional files and is available at http://www.ru.nl/publish/pages/726696/rankprodbounds.zip .

Energy Bounds for a Compressed Elastic Film on a Substrate

NASA Astrophysics Data System (ADS)

Bourne, David P.; Conti, Sergio; Müller, Stefan

2017-04-01

We study pattern formation in a compressed elastic film which delaminates from a substrate. Our key tool is the determination of rigorous upper and lower bounds on the minimum value of a suitable energy functional. The energy consists of two parts, describing the two main physical effects. The first part represents the elastic energy of the film, which is approximated using the von Kármán plate theory. The second part represents the fracture or delamination energy, which is approximated using the Griffith model of fracture. A simpler model containing the first term alone was previously studied with similar methods by several authors, assuming that the delaminated region is fixed. We include the fracture term, transforming the elastic minimisation into a free boundary problem, and opening the way for patterns which result from the interplay of elasticity and delamination. After rescaling, the energy depends on only two parameters: the rescaled film thickness, {σ }, and a measure of the bonding strength between the film and substrate, {γ }. We prove upper bounds on the minimum energy of the form {σ }^a {γ }^b and find that there are four different parameter regimes corresponding to different values of a and b and to different folding patterns of the film. In some cases, the upper bounds are attained by self-similar folding patterns as observed in experiments. Moreover, for two of the four parameter regimes we prove matching, optimal lower bounds.

Chameleon-photon mixing in a primordial magnetic field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schelpe, Camilla A. O.

2010-08-15

The existence of a sizable, O(10{sup -10}-10{sup -9} G), cosmological magnetic field in the early Universe has been postulated as a necessary step in certain formation scenarios for the large-scale O({mu}G) magnetic fields found in galaxies and galaxy clusters. If this field exists then it may induce significant mixing between photons and axion-like particles (ALPs) in the early Universe. The resonant conversion of photons into ALPs in a primordial magnetic field has been studied elsewhere by Mirizzi, Redondo and Sigl (2009). Here we consider the nonresonant mixing between photons and scalar ALPs with masses much less than the plasma frequencymore » along the path, with specific reference to the chameleon scalar field model. The mixing would alter the intensity and polarization state of the cosmic microwave background (CMB) radiation. We find that the average modification to the CMB polarization modes is negligible. However the average modification to the CMB intensity spectrum is more significant and we compare this to high-precision measurements of the CMB monopole made by the far infrared absolute spectrophotometer on board the COBE satellite. The resulting 95% confidence limit on the scalar-photon conversion probability in the primordial field (at 100 GHz) is P{sub {gamma}{r_reversible}{phi}<}2.6x10{sup -2}. This corresponds to a degenerate constraint on the photon-scalar coupling strength, g{sub eff}, and the magnitude of the primordial magnetic field. Taking the upper bound on the strength of the primordial magnetic field derived from the CMB power spectra, B{sub {lambda}{<=}5}.0x10{sup -9} G, this would imply an upper bound on the photon-scalar coupling strength in the range g{sub eff} < or approx. 7.14x10{sup -13} GeV{sup -1} to g{sub eff} < or approx. 9.20x10{sup -14} GeV{sup -1}, depending on the power spectrum of the primordial magnetic field.« less

The Quantum Measurement Problem and Physical reality: A Computation Theoretic Perspective

NASA Astrophysics Data System (ADS)

Srikanth, R.

2006-11-01

Is the universe computable? If yes, is it computationally a polynomial place? In standard quantum mechanics, which permits infinite parallelism and the infinitely precise specification of states, a negative answer to both questions is not ruled out. On the other hand, empirical evidence suggests that NP-complete problems are intractable in the physical world. Likewise, computational problems known to be algorithmically uncomputable do not seem to be computable by any physical means. We suggest that this close correspondence between the efficiency and power of abstract algorithms on the one hand, and physical computers on the other, finds a natural explanation if the universe is assumed to be algorithmic; that is, that physical reality is the product of discrete sub-physical information processing equivalent to the actions of a probabilistic Turing machine. This assumption can be reconciled with the observed exponentiality of quantum systems at microscopic scales, and the consequent possibility of implementing Shor's quantum polynomial time algorithm at that scale, provided the degree of superposition is intrinsically, finitely upper-bounded. If this bound is associated with the quantum-classical divide (the Heisenberg cut), a natural resolution to the quantum measurement problem arises. From this viewpoint, macroscopic classicality is an evidence that the universe is in BPP, and both questions raised above receive affirmative answers. A recently proposed computational model of quantum measurement, which relates the Heisenberg cut to the discreteness of Hilbert space, is briefly discussed. A connection to quantum gravity is noted. Our results are compatible with the philosophy that mathematical truths are independent of the laws of physics.

Saturn's very axisymmetric magnetic field: No detectable secular variation or tilt

NASA Astrophysics Data System (ADS)

Cao, Hao; Russell, Christopher T.; Christensen, Ulrich R.; Dougherty, Michele K.; Burton, Marcia E.

2011-04-01

Saturn is the only planet in the solar system whose observed magnetic field is highly axisymmetric. At least a small deviation from perfect symmetry is required for a dynamo-generated magnetic field. Analyzing more than six years of magnetometer data obtained by Cassini close to the planet, we show that Saturn's observed field is much more axisymmetric than previously thought. We invert the magnetometer observations that were obtained in the "current-free" inner magnetosphere for an internal model, varying the assumed unknown rotation rate of Saturn's deep interior. No unambiguous non-axially symmetric magnetic moment is detected, with a new upper bound on the dipole tilt of 0.06°. An axisymmetric internal model with Schmidt-normalized spherical harmonic coefficients g10 = 21,191 ± 24 nT, g20 = 1586 ± 7 nT. g30 = 2374 ± 47 nT is derived from these measurements, the upper bounds on the axial degree 4 and 5 terms are 720 nT and 3200 nT respectively. The secular variation for the last 30 years is within the probable error of each term from degree 1 to 3, and the upper bounds are an order of magnitude smaller than in similar terrestrial terms for degrees 1 and 2. Differentially rotating conducting stable layers above Saturn's dynamo region have been proposed to symmetrize the magnetic field (Stevenson, 1982). The new upper bound on the dipole tilt implies that this stable layer must have a thickness L >= 4000 km, and this thickness is consistent with our weak secular variation observations.

Spacetime deformation effect on the early universe and the PTOLEMY experiment

NASA Astrophysics Data System (ADS)

Horvat, Raul; Trampetic, Josip; You, Jiangyang

2017-09-01

Using a fully-fledged formulation of gauge field theory deformed by the spacetime noncommutativity, we study its impact on relic neutrino direct detection, as proposed recently by the PTOLEMY experiment. The noncommutative background tends to influence the propagating neutrinos by providing them with a tree-level vector-like coupling to photons, enabling thus otherwise sterile right-handed (RH) neutrinos to be thermally produced in the early universe. Such a new component in the universe's background radiation has been switched today to the almost fully active sea of non-relativistic neutrinos, exerting consequently some impact on the capture on tritium at PTOLEMY. The peculiarities of our nonperturbative approach tend to reflect in the cosmology as well, upon the appearances of the coupling temperature, above which RH neutrinos stay permanently decoupled from thermal environment. This entails the maximal scale of noncommutativity as well, being of order of 10-4MPl, above which there is no impact whatsoever on the capture rates at PTOLEMY. The latter represents an exceptional upper bound on the scale of noncommutativity coming from phenomenology.

Biodegradation kinetics for pesticide exposure assessment.

PubMed

Wolt, J D; Nelson, H P; Cleveland, C B; van Wesenbeeck, I J

2001-01-01

Understanding pesticide risks requires characterizing pesticide exposure within the environment in a manner that can be broadly generalized across widely varied conditions of use. The coupled processes of sorption and soil degradation are especially important for understanding the potential environmental exposure of pesticides. The data obtained from degradation studies are inherently variable and, when limited in extent, lend uncertainty to exposure characterization and risk assessment. Pesticide decline in soils reflects dynamically coupled processes of sorption and degradation that add complexity to the treatment of soil biodegradation data from a kinetic perspective. Additional complexity arises from study design limitations that may not fully account for the decline in microbial activity of test systems, or that may be inadequate for considerations of all potential dissipation routes for a given pesticide. Accordingly, kinetic treatment of data must accommodate a variety of differing approaches starting with very simple assumptions as to reaction dynamics and extending to more involved treatments if warranted by the available experimental data. Selection of the appropriate kinetic model to describe pesticide degradation should rely on statistical evaluation of the data fit to ensure that the models used are not overparameterized. Recognizing the effects of experimental conditions and methods for kinetic treatment of degradation data is critical for making appropriate comparisons among pesticide biodegradation data sets. Assessment of variability in soil half-life among soils is uncertain because for many pesticides the data on soil degradation rate are limited to one or two soils. Reasonable upper-bound estimates of soil half-life are necessary in risk assessment so that estimated environmental concentrations can be developed from exposure models. Thus, an understanding of the variable and uncertain distribution of soil half-lives in the environment is necessary to estimate bounding values. Statistical evaluation of measures of central tendency for multisoil kinetic studies shows that geometric means better represent the distribution in soil half-lives than do the arithmetic or harmonic means. Estimates of upper-bound soil half-life values based on the upper 90% confidence bound on the geometric mean tend to accurately represent the upper bound when pesticide degradation rate is biologically driven but appear to overestimate the upper bound when there is extensive coupling of biodegradation with sorptive processes. The limited data available comparing distribution in pesticide soil half-lives between multisoil laboratory studies and multilocation field studies suggest that the probability density functions are similar. Thus, upper-bound estimates of pesticide half-life determined from laboratory studies conservatively represent pesticide biodegradation in the field environment for the purposes of exposure and risk assessment. International guidelines and approaches used for interpretations of soil biodegradation reflect many common elements, but differ in how the source and nature of variability in soil kinetic data are considered. Harmonization of approaches for the use of soil biodegradation data will improve the interpretative power of these data for the purposes of exposure and risk assessment.

Jarzynski equality: connections to thermodynamics and the second law.

PubMed

Palmieri, Benoit; Ronis, David

2007-01-01

The one-dimensional expanding ideal gas model is used to compute the exact nonequilibrium distribution function. The state of the system during the expansion is defined in terms of local thermodynamics quantities. The final equilibrium free energy, obtained a long time after the expansion, is compared against the free energy that appears in the Jarzynski equality. Within this model, where the Jarzynski equality holds rigorously, the free energy change that appears in the equality does not equal the actual free energy change of the system at any time of the process. More generally, the work bound that is obtained from the Jarzynski equality is an upper bound to the upper bound that is obtained from the first and second laws of thermodynamics. The cancellation of the dissipative (nonequilibrium) terms that result in the Jarzynski equality is shown in the framework of response theory. This is used to show that the intuitive assumption that the Jarzynski work bound becomes equal to the average work done when the system evolves quasistatically is incorrect under some conditions.

More on the decoder error probability for Reed-Solomon codes

NASA Technical Reports Server (NTRS)

Cheung, K.-M.

1987-01-01

The decoder error probability for Reed-Solomon codes (more generally, linear maximum distance separable codes) is examined. McEliece and Swanson offered an upper bound on P sub E (u), the decoder error probability given that u symbol errors occurs. This upper bound is slightly greater than Q, the probability that a completely random error pattern will cause decoder error. By using a combinatoric technique, the principle of inclusion and exclusion, an exact formula for P sub E (u) is derived. The P sub e (u) for the (255, 223) Reed-Solomon Code used by NASA, and for the (31,15) Reed-Solomon code (JTIDS code), are calculated using the exact formula, and the P sub E (u)'s are observed to approach the Q's of the codes rapidly as u gets larger. An upper bound for the expression is derived, and is shown to decrease nearly exponentially as u increases. This proves analytically that P sub E (u) indeed approaches Q as u becomes large, and some laws of large numbers come into play.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baker, Kyri; Toomey, Bridget

Evolving power systems with increasing levels of stochasticity call for a need to solve optimal power flow problems with large quantities of random variables. Weather forecasts, electricity prices, and shifting load patterns introduce higher levels of uncertainty and can yield optimization problems that are difficult to solve in an efficient manner. Solution methods for single chance constraints in optimal power flow problems have been considered in the literature, ensuring single constraints are satisfied with a prescribed probability; however, joint chance constraints, ensuring multiple constraints are simultaneously satisfied, have predominantly been solved via scenario-based approaches or by utilizing Boole's inequality asmore » an upper bound. In this paper, joint chance constraints are used to solve an AC optimal power flow problem while preventing overvoltages in distribution grids under high penetrations of photovoltaic systems. A tighter version of Boole's inequality is derived and used to provide a new upper bound on the joint chance constraint, and simulation results are shown demonstrating the benefit of the proposed upper bound. The new framework allows for a less conservative and more computationally efficient solution to considering joint chance constraints, specifically regarding preventing overvoltages.« less

Lorenz curves in a new science-funding model

NASA Astrophysics Data System (ADS)

Huang, Ding-wei

2017-12-01

We propose an agent-based model to theoretically and systematically explore the implications of a new approach to fund science, which has been suggested recently by J. Bollen et al.[?] We introduce various parameters and examine their effects. The concentration of funding is shown by the Lorenz curve and the Gini coefficient. In this model, all scientists are treated equally and follow the well-intended regulations. All scientists give a fixed ratio of their funding to others. The fixed ratio becomes an upper bound for the Gini coefficient. We observe two distinct regimes in the parameter space: valley and plateau. In the valley regime, the fluidity of funding is significant. The Lorenz curve is smooth. The Gini coefficient is well below the upper bound. The funding distribution is the desired result. In the plateau regime, the cumulative advantage is significant. The Lorenz curve has a sharp turn. The Gini coefficient saturates to the upper bound. The undue concentration of funding happens swiftly. The funding distribution is the undesired results, where a minority of scientists take the majority of funding. Phase transitions between these two regimes are discussed.

Expected performance of m-solution backtracking

NASA Technical Reports Server (NTRS)

Nicol, D. M.

1986-01-01

This paper derives upper bounds on the expected number of search tree nodes visited during an m-solution backtracking search, a search which terminates after some preselected number m problem solutions are found. The search behavior is assumed to have a general probabilistic structure. The results are stated in terms of node expansion and contraction. A visited search tree node is said to be expanding if the mean number of its children visited by the search exceeds 1 and is contracting otherwise. It is shown that if every node expands, or if every node contracts, then the number of search tree nodes visited by a search has an upper bound which is linear in the depth of the tree, in the mean number of children a node has, and in the number of solutions sought. Also derived are bounds linear in the depth of the tree in some situations where an upper portion of the tree contracts (expands), while the lower portion expands (contracts). While previous analyses of 1-solution backtracking have concluded that the expected performance is always linear in the tree depth, the model allows superlinear expected performance.

Error control techniques for satellite and space communications

NASA Technical Reports Server (NTRS)

Costello, Daniel J., Jr.

1990-01-01

An expurgated upper bound on the event error probability of trellis coded modulation is presented. This bound is used to derive a lower bound on the minimum achievable free Euclidean distance d sub (free) of trellis codes. It is shown that the dominant parameters for both bounds, the expurgated error exponent and the asymptotic d sub (free) growth rate, respectively, can be obtained from the cutoff-rate R sub O of the transmission channel by a simple geometric construction, making R sub O the central parameter for finding good trellis codes. Several constellations are optimized with respect to the bounds.

Variability in sinking fluxes and composition of particle-bound phosphorus in the Xisha area of the northern South China Sea

NASA Astrophysics Data System (ADS)

Dong, Yuan; Li, Qian P.; Wu, Zhengchao; Zhang, Jia-Zhong

2016-12-01

Export fluxes of phosphorus (P) by sinking particles are important in studying ocean biogeochemical dynamics, whereas their composition and temporal variability are still inadequately understood in the global oceans, including the northern South China Sea (NSCS). A time-series study of particle fluxes was conducted at a mooring station adjacent to the Xisha Trough in the NSCS from September 2012 to September 2014, with sinking particles collected every two weeks by two sediment traps deployed at 500 m and 1500 m depths. Five operationally defined particulate P classes of sinking particles including loosely-bound P, Fe-bound P, CaCO3-bound P, detrital apatite P, and refractory organic P were quantified by a sequential extraction method (SEDEX). Our results revealed substantial variability in sinking particulate P composition at the Xisha over two years of samplings. Particulate inorganic P was largely contributed from Fe-bound P in the upper trap, but detrital P in the lower trap. Particulate organic P, including exchangeable organic P, CaCO3-bound organic P, and refractory organic P, contributed up to 50-55% of total sinking particulate P. Increase of CaCO3-bound P in the upper trap during 2014 could be related to a strong El Niño event with enhanced CaCO3 deposition. We also found sediment resuspension responsible for the unusual high particles fluxes at the lower trap based on analyses of a two-component mixing model. There was on average a total mass flux of 78±50 mg m-2 d-1 at the upper trap during the study period. A significant correlation between integrated primary productivity in the region and particle fluxes at 500 m of the station suggested the important role of biological production in controlling the concentration, composition, and export fluxes of sinking particulate P in the NSCS.

ON COMPUTING UPPER LIMITS TO SOURCE INTENSITIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kashyap, Vinay L.; Siemiginowska, Aneta; Van Dyk, David A.

2010-08-10

A common problem in astrophysics is determining how bright a source could be and still not be detected in an observation. Despite the simplicity with which the problem can be stated, the solution involves complicated statistical issues that require careful analysis. In contrast to the more familiar confidence bound, this concept has never been formally analyzed, leading to a great variety of often ad hoc solutions. Here we formulate and describe the problem in a self-consistent manner. Detection significance is usually defined by the acceptable proportion of false positives (background fluctuations that are claimed as detections, or Type I error),more » and we invoke the complementary concept of false negatives (real sources that go undetected, or Type II error), based on the statistical power of a test, to compute an upper limit to the detectable source intensity. To determine the minimum intensity that a source must have for it to be detected, we first define a detection threshold and then compute the probabilities of detecting sources of various intensities at the given threshold. The intensity that corresponds to the specified Type II error probability defines that minimum intensity and is identified as the upper limit. Thus, an upper limit is a characteristic of the detection procedure rather than the strength of any particular source. It should not be confused with confidence intervals or other estimates of source intensity. This is particularly important given the large number of catalogs that are being generated from increasingly sensitive surveys. We discuss, with examples, the differences between these upper limits and confidence bounds. Both measures are useful quantities that should be reported in order to extract the most science from catalogs, though they answer different statistical questions: an upper bound describes an inference range on the source intensity, while an upper limit calibrates the detection process. We provide a recipe for computing upper limits that applies to all detection algorithms.« less

Efficiency of a thermodynamic motor at maximum power

NASA Astrophysics Data System (ADS)

Moreau, M.; Gaveau, B.; Schulman, L. S.

2012-02-01

Several recent theories address the efficiency of a macroscopic thermodynamic motor at maximum power and question the so-called Curzon-Ahlborn (CA) efficiency. Considering the entropy exchanges and productions in an n-sources motor, we study the maximization of its power and show that the controversies are partly due to some imprecision in the maximization variables. When power is maximized with respect to the system temperatures, these temperatures are proportional to the square root of the corresponding source temperatures, which leads to the CA formula for a bithermal motor. On the other hand, when power is maximized with respect to the transition durations, the Carnot efficiency of a bithermal motor admits the CA efficiency as a lower bound, which is attained if the duration of the adiabatic transitions can be neglected. Additionally, we compute the energetic efficiency, or “sustainable efficiency,” which can be defined for n sources, and we show that it has no other universal upper bound than 1, but that in certain situations, which are favorable for power production, it does not exceed ½.

Efficiency of a thermodynamic motor at maximum power.

PubMed

Moreau, M; Gaveau, B; Schulman, L S

2012-02-01

Several recent theories address the efficiency of a macroscopic thermodynamic motor at maximum power and question the so-called Curzon-Ahlborn (CA) efficiency. Considering the entropy exchanges and productions in an n-sources motor, we study the maximization of its power and show that the controversies are partly due to some imprecision in the maximization variables. When power is maximized with respect to the system temperatures, these temperatures are proportional to the square root of the corresponding source temperatures, which leads to the CA formula for a bithermal motor. On the other hand, when power is maximized with respect to the transition durations, the Carnot efficiency of a bithermal motor admits the CA efficiency as a lower bound, which is attained if the duration of the adiabatic transitions can be neglected. Additionally, we compute the energetic efficiency, or "sustainable efficiency," which can be defined for n sources, and we show that it has no other universal upper bound than 1, but that in certain situations, which are favorable for power production, it does not exceed ½. © 2012 American Physical Society

Bounds and inequalities relating h-index, g-index, e-index and generalized impact factor: an improvement over existing models.

PubMed

Abbas, Ash Mohammad

2012-01-01

In this paper, we describe some bounds and inequalities relating h-index, g-index, e-index, and generalized impact factor. We derive the bounds and inequalities relating these indexing parameters from their basic definitions and without assuming any continuous model to be followed by any of them. We verify the theorems using citation data for five Price Medalists. We observe that the lower bound for h-index given by Theorem 2, [formula: see text], g ≥ 1, comes out to be more accurate as compared to Schubert-Glanzel relation h is proportional to C(2/3)P(-1/3) for a proportionality constant of 1, where C is the number of citations and P is the number of papers referenced. Also, the values of h-index obtained using Theorem 2 outperform those obtained using Egghe-Liang-Rousseau power law model for the given citation data of Price Medalists. Further, we computed the values of upper bound on g-index given by Theorem 3, g ≤ (h + e), where e denotes the value of e-index. We observe that the upper bound on g-index given by Theorem 3 is reasonably tight for the given citation record of Price Medalists.

Reverse preferential spread in complex networks

NASA Astrophysics Data System (ADS)

Toyoizumi, Hiroshi; Tani, Seiichi; Miyoshi, Naoto; Okamoto, Yoshio

2012-08-01

Large-degree nodes may have a larger influence on the network, but they can be bottlenecks for spreading information since spreading attempts tend to concentrate on these nodes and become redundant. We discuss that the reverse preferential spread (distributing information inversely proportional to the degree of the receiving node) has an advantage over other spread mechanisms. In large uncorrelated networks, we show that the mean number of nodes that receive information under the reverse preferential spread is an upper bound among any other weight-based spread mechanisms, and this upper bound is indeed a logistic growth independent of the degree distribution.

A note on the upper bound of the spectral radius for SOR iteration matrix

NASA Astrophysics Data System (ADS)

Chang, D.-W. Da-Wei

2004-05-01

Recently, Wang and Huang (J. Comput. Appl. Math. 135 (2001) 325, Corollary 4.7) established the following estimation on the upper bound of the spectral radius for successive overrelaxation (SOR) iteration matrix:ρSOR≤1-ω+ωρGSunder the condition that the coefficient matrix A is a nonsingular M-matrix and ω≥1, where ρSOR and ρGS are the spectral radius of SOR iteration matrix and Gauss-Seidel iteration matrix, respectively. In this note, we would like to point out that the above estimation is not valid in general.

A Novel Capacity Analysis for Wireless Backhaul Mesh Networks

NASA Astrophysics Data System (ADS)

Chung, Tein-Yaw; Lee, Kuan-Chun; Lee, Hsiao-Chih

This paper derived a closed-form expression for inter-flow capacity of a backhaul wireless mesh network (WMN) with centralized scheduling by employing a ring-based approach. Through the definition of an interference area, we are able to accurately describe a bottleneck collision area for a WMN and calculate the upper bound of inter-flow capacity. The closed-form expression shows that the upper bound is a function of the ratio between transmission range and network radius. Simulations and numerical analysis show that our analytic solution can better estimate the inter-flow capacity of WMNs than that of previous approach.

On the error probability of general tree and trellis codes with applications to sequential decoding

NASA Technical Reports Server (NTRS)

Johannesson, R.

1973-01-01

An upper bound on the average error probability for maximum-likelihood decoding of the ensemble of random binary tree codes is derived and shown to be independent of the length of the tree. An upper bound on the average error probability for maximum-likelihood decoding of the ensemble of random L-branch binary trellis codes of rate R = 1/n is derived which separates the effects of the tail length T and the memory length M of the code. It is shown that the bound is independent of the length L of the information sequence. This implication is investigated by computer simulations of sequential decoding utilizing the stack algorithm. These simulations confirm the implication and further suggest an empirical formula for the true undetected decoding error probability with sequential decoding.

Efficient Regressions via Optimally Combining Quantile Information*

PubMed Central

Zhao, Zhibiao; Xiao, Zhijie

2014-01-01

We develop a generally applicable framework for constructing efficient estimators of regression models via quantile regressions. The proposed method is based on optimally combining information over multiple quantiles and can be applied to a broad range of parametric and nonparametric settings. When combining information over a fixed number of quantiles, we derive an upper bound on the distance between the efficiency of the proposed estimator and the Fisher information. As the number of quantiles increases, this upper bound decreases and the asymptotic variance of the proposed estimator approaches the Cramér-Rao lower bound under appropriate conditions. In the case of non-regular statistical estimation, the proposed estimator leads to super-efficient estimation. We illustrate the proposed method for several widely used regression models. Both asymptotic theory and Monte Carlo experiments show the superior performance over existing methods. PMID:25484481

Toward allocative efficiency in the prescription drug industry.

PubMed

Guell, R C; Fischbaum, M

1995-01-01

Traditionally, monopoly power in the pharmaceutical industry has been measured by profits. An alternative method estimates the deadweight loss of consumer surplus associated with the exercise of monopoly power. Although upper and lower bound estimates for this inefficiency are far apart, they at least suggest a dramatically greater welfare loss than measures of industry profitability would imply. A proposed system would have the U.S. government employing its power of eminent domain to "take" and distribute pharmaceutical patents, providing as "just compensation" the present value of the patent's expected future monopoly profits. Given the allocative inefficiency of raising taxes to pay for the program, the impact of the proposal on allocative efficiency would be at least as good at our lower bound estimate of monopoly costs while substantially improving efficiency at or near our upper bound estimate.

Tight upper bound for the maximal quantum value of the Svetlichny operators

NASA Astrophysics Data System (ADS)

Li, Ming; Shen, Shuqian; Jing, Naihuan; Fei, Shao-Ming; Li-Jost, Xianqing

2017-10-01

It is a challenging task to detect genuine multipartite nonlocality (GMNL). In this paper, the problem is considered via computing the maximal quantum value of Svetlichny operators for three-qubit systems and a tight upper bound is obtained. The constraints on the quantum states for the tightness of the bound are also presented. The approach enables us to give the necessary and sufficient conditions of violating the Svetlichny inequality (SI) for several quantum states, including the white and color noised Greenberger-Horne-Zeilinger (GHZ) states. The relation between the genuine multipartite entanglement concurrence and the maximal quantum value of the Svetlichny operators for mixed GHZ class states is also discussed. As the SI is useful for the investigation of GMNL, our results give an effective and operational method to detect the GMNL for three-qubit mixed states.

Locality of Temperature

NASA Astrophysics Data System (ADS)

Kliesch, M.; Gogolin, C.; Kastoryano, M. J.; Riera, A.; Eisert, J.

2014-07-01

This work is concerned with thermal quantum states of Hamiltonians on spin- and fermionic-lattice systems with short-range interactions. We provide results leading to a local definition of temperature, thereby extending the notion of "intensivity of temperature" to interacting quantum models. More precisely, we derive a perturbation formula for thermal states. The influence of the perturbation is exactly given in terms of a generalized covariance. For this covariance, we prove exponential clustering of correlations above a universal critical temperature that upper bounds physical critical temperatures such as the Curie temperature. As a corollary, we obtain that above the critical temperature, thermal states are stable against distant Hamiltonian perturbations. Moreover, our results imply that above the critical temperature, local expectation values can be approximated efficiently in the error and the system size.

Vacuum stability in the U(1)χ extended model with vanishing scalar potential at the Planck scale

NASA Astrophysics Data System (ADS)

Haba, Naoyuki; Yamaguchi, Yuya

2015-09-01

We investigate the vacuum stability in a scale invariant local {U}(1)_χ model with vanishing scalar potential at the Planck scale. We find that it is impossible to realize the Higgs mass of 125 GeV while keeping the Higgs quartic coupling λ _H positive in all energy scales, that is, the same as the standard model. Once one allows λ _H<0, the lower bounds of the Z' boson mass ares obtained through the positive definiteness of the scalar mass squared eigenvalues, while the bounds are smaller than the LHC bounds. On the other hand, the upper bounds strongly depend on the number of relevant Majorana Yukawa couplings of the right-handed neutrinos N_ν . Considering decoupling effects of the Z' boson and the right-handed neutrinos, the condition of the singlet scalar quartic coupling λ _φ >0 gives the upper bound in the N_ν =1 case, while it does not constrain the N_ν =2 and 3 cases. In particular, we find that the Z' boson mass is tightly restricted for the N_ν =1 case as M_{Z'} &lsim 3.7 TeV.

Universal bound on the efficiency of molecular motors

NASA Astrophysics Data System (ADS)

Pietzonka, Patrick; Barato, Andre C.; Seifert, Udo

2016-12-01

The thermodynamic uncertainty relation provides an inequality relating any mean current, the associated dispersion and the entropy production rate for arbitrary non-equilibrium steady states. Applying it here to a general model of a molecular motor running against an external force or torque, we show that the thermodynamic efficiency of such motors is universally bounded by an expression involving only experimentally accessible quantities. For motors pulling cargo through a viscous fluid, a universal bound for the corresponding Stokes efficiency follows as a variant. A similar result holds if mechanical force is used to synthesize molecules of high chemical potential. Crucially, no knowledge of the detailed underlying mechano-chemical mechanism is required for applying these bounds.

$$ \\mathcal{N} $$ = 4 superconformal bootstrap of the K 3 CFT

DOE PAGES

Lin, Ying-Hsuan; Shao, Shu-Heng; Simmons-Duffin, David; ...

2017-05-23

We study two-dimensional (4; 4) superconformal eld theories of central charge c = 6, corresponding to nonlinear sigma models on K3 surfaces, using the superconformal bootstrap. This is made possible through a surprising relation between the BPS N = 4 superconformal blocks with c = 6 and bosonic Virasoro conformal blocks with c = 28, and an exact result on the moduli dependence of a certain integrated BPS 4-point function. Nontrivial bounds on the non-BPS spectrum in the K3 CFT are obtained as functions of the CFT moduli, that interpolate between the free orbifold points and singular CFT points. Wemore » observe directly from the CFT perspective the signature of a continuous spectrum above a gap at the singular moduli, and fi nd numerically an upper bound on this gap that is saturated by the A1 N = 4 cigar CFT. We also derive an analytic upper bound on the fi rst nonzero eigenvalue of the scalar Laplacian on K3 in the large volume regime, that depends on the K3 moduli data. As two byproducts, we find an exact equivalence between a class of BPS N = 2 superconformal blocks and Virasoro conformal blocks in two dimensions, and an upper bound on the four-point functions of operators of sufficiently low scaling dimension in three and four dimensional CFTs.« less

$$ \\mathcal{N} $$ = 4 superconformal bootstrap of the K 3 CFT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Ying-Hsuan; Shao, Shu-Heng; Simmons-Duffin, David

We study two-dimensional (4; 4) superconformal eld theories of central charge c = 6, corresponding to nonlinear sigma models on K3 surfaces, using the superconformal bootstrap. This is made possible through a surprising relation between the BPS N = 4 superconformal blocks with c = 6 and bosonic Virasoro conformal blocks with c = 28, and an exact result on the moduli dependence of a certain integrated BPS 4-point function. Nontrivial bounds on the non-BPS spectrum in the K3 CFT are obtained as functions of the CFT moduli, that interpolate between the free orbifold points and singular CFT points. Wemore » observe directly from the CFT perspective the signature of a continuous spectrum above a gap at the singular moduli, and fi nd numerically an upper bound on this gap that is saturated by the A1 N = 4 cigar CFT. We also derive an analytic upper bound on the fi rst nonzero eigenvalue of the scalar Laplacian on K3 in the large volume regime, that depends on the K3 moduli data. As two byproducts, we find an exact equivalence between a class of BPS N = 2 superconformal blocks and Virasoro conformal blocks in two dimensions, and an upper bound on the four-point functions of operators of sufficiently low scaling dimension in three and four dimensional CFTs.« less

Comonotonic bounds on the survival probabilities in the Lee-Carter model for mortality projection

NASA Astrophysics Data System (ADS)

Denuit, Michel; Dhaene, Jan

2007-06-01

In the Lee-Carter framework, future survival probabilities are random variables with an intricate distribution function. In large homogeneous portfolios of life annuities, value-at-risk or conditional tail expectation of the total yearly payout of the company are approximately equal to the corresponding quantities involving random survival probabilities. This paper aims to derive some bounds in the increasing convex (or stop-loss) sense on these random survival probabilities. These bounds are obtained with the help of comonotonic upper and lower bounds on sums of correlated random variables.

Theoretical investigation of the upper and lower bounds of a generalized dimensionless bearing health indicator

NASA Astrophysics Data System (ADS)

Wang, Dong; Tsui, Kwok-Leung

2018-01-01

Bearing-supported shafts are widely used in various machines. Due to harsh working environments, bearing performance degrades over time. To prevent unexpected bearing failures and accidents, bearing performance degradation assessment becomes an emerging topic in recent years. Bearing performance degradation assessment aims to evaluate the current health condition of a bearing through a bearing health indicator. In the past years, many signal processing and data mining based methods were proposed to construct bearing health indicators. However, the upper and lower bounds of these bearing health indicators were not theoretically calculated and they strongly depended on historical bearing data including normal and failure data. Besides, most health indicators are dimensional, which connotes that these health indicators are prone to be affected by varying operating conditions, such as varying speeds and loads. In this paper, based on the principle of squared envelope analysis, we focus on theoretical investigation of bearing performance degradation assessment in the case of additive Gaussian noises, including distribution establishment of squared envelope, construction of a generalized dimensionless bearing health indicator, and mathematical calculation of the upper and lower bounds of the generalized dimensionless bearing health indicator. Then, analyses of simulated and real bearing run to failure data are used as two case studies to illustrate how the generalized dimensionless health indicator works and demonstrate its effectiveness in bearing performance degradation assessment. Results show that squared envelope follows a noncentral chi-square distribution and the upper and lower bounds of the generalized dimensionless health indicator can be mathematically established. Moreover, the generalized dimensionless health indicator is sensitive to an incipient bearing defect in the process of bearing performance degradation.

Jefferson's Academical Village, Bounded by University Avenue on the north, ...

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

Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

Reionization during the dark ages from a cosmic axion background

DOE Office of Scientific and Technical Information (OSTI.GOV)

Evoli, Carmelo; Leo, Matteo; Mirizzi, Alessandro

2016-05-01

Recently it has been pointed out that a cosmic background of relativistic axion-like particles (ALPs) would be produced by the primordial decays of heavy fields in the post-inflation epoch, contributing to the extra-radiation content in the Universe today. Primordial magnetic fields would trigger conversions of these ALPs into sub-MeV photons during the dark ages. This photon flux would produce an early reionization of the Universe, leaving a significant imprint on the total optical depth to recombination τ. Using the current measurement of τ and the limit on the extra-radiation content Δ N {sub eff} by the Planck experiment we putmore » a strong bound on the ALP-photon conversions. Namely we obtain upper limits on the product of the photon-ALP coupling constant g {sub a} {sub γ} times the magnetic field strength B down to g {sub a} {sub γ} B ∼> 6 × 10{sup −18} GeV{sup −1} nG for ultralight ALPs.« less

``Carbon Credits'' for Resource-Bounded Computations Using Amortised Analysis

NASA Astrophysics Data System (ADS)

Jost, Steffen; Loidl, Hans-Wolfgang; Hammond, Kevin; Scaife, Norman; Hofmann, Martin

Bounding resource usage is important for a number of areas, notably real-time embedded systems and safety-critical systems. In this paper, we present a fully automatic static type-based analysis for inferring upper bounds on resource usage for programs involving general algebraic datatypes and full recursion. Our method can easily be used to bound any countable resource, without needing to revisit proofs. We apply the analysis to the important metrics of worst-case execution time, stack- and heap-space usage. Our results from several realistic embedded control applications demonstrate good matches between our inferred bounds and measured worst-case costs for heap and stack usage. For time usage we infer good bounds for one application. Where we obtain less tight bounds, this is due to the use of software floating-point libraries.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Azunre, P.

Here in this paper, two novel techniques for bounding the solutions of parametric weakly coupled second-order semilinear parabolic partial differential equations are developed. The first provides a theorem to construct interval bounds, while the second provides a theorem to construct lower bounds convex and upper bounds concave in the parameter. The convex/concave bounds can be significantly tighter than the interval bounds because of the wrapping effect suffered by interval analysis in dynamical systems. Both types of bounds are computationally cheap to construct, requiring solving auxiliary systems twice and four times larger than the original system, respectively. An illustrative numerical examplemore » of bound construction and use for deterministic global optimization within a simple serial branch-and-bound algorithm, implemented numerically using interval arithmetic and a generalization of McCormick's relaxation technique, is presented. Finally, problems within the important class of reaction-diffusion systems may be optimized with these tools.« less

Adaptive and bounded investment returns promote cooperation in spatial public goods games.

PubMed

Chen, Xiaojie; Liu, Yongkui; Zhou, Yonghui; Wang, Long; Perc, Matjaž

2012-01-01

The public goods game is one of the most famous models for studying the evolution of cooperation in sizable groups. The multiplication factor in this game can characterize the investment return from the public good, which may be variable depending on the interactive environment in realistic situations. Instead of using the same universal value, here we consider that the multiplication factor in each group is updated based on the differences between the local and global interactive environments in the spatial public goods game, but meanwhile limited to within a certain range. We find that the adaptive and bounded investment returns can significantly promote cooperation. In particular, full cooperation can be achieved for high feedback strength when appropriate limitation is set for the investment return. Also, we show that the fraction of cooperators in the whole population can become larger if the lower and upper limits of the multiplication factor are increased. Furthermore, in comparison to the traditionally spatial public goods game where the multiplication factor in each group is identical and fixed, we find that cooperation can be better promoted if the multiplication factor is constrained to adjust between one and the group size in our model. Our results highlight the importance of the locally adaptive and bounded investment returns for the emergence and dominance of cooperative behavior in structured populations.

Adaptive and Bounded Investment Returns Promote Cooperation in Spatial Public Goods Games

PubMed Central

Chen, Xiaojie; Liu, Yongkui; Zhou, Yonghui; Wang, Long; Perc, Matjaž

2012-01-01

The public goods game is one of the most famous models for studying the evolution of cooperation in sizable groups. The multiplication factor in this game can characterize the investment return from the public good, which may be variable depending on the interactive environment in realistic situations. Instead of using the same universal value, here we consider that the multiplication factor in each group is updated based on the differences between the local and global interactive environments in the spatial public goods game, but meanwhile limited to within a certain range. We find that the adaptive and bounded investment returns can significantly promote cooperation. In particular, full cooperation can be achieved for high feedback strength when appropriate limitation is set for the investment return. Also, we show that the fraction of cooperators in the whole population can become larger if the lower and upper limits of the multiplication factor are increased. Furthermore, in comparison to the traditionally spatial public goods game where the multiplication factor in each group is identical and fixed, we find that cooperation can be better promoted if the multiplication factor is constrained to adjust between one and the group size in our model. Our results highlight the importance of the locally adaptive and bounded investment returns for the emergence and dominance of cooperative behavior in structured populations. PMID:22615836

1. Title Sheet Jefferson's Academical Village, Bounded by University ...

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

1. Title Sheet - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

Effects of triplet Higgs bosons in long baseline neutrino experiments

NASA Astrophysics Data System (ADS)

Huitu, K.; Kärkkäinen, T. J.; Maalampi, J.; Vihonen, S.

2018-05-01

The triplet scalars (Δ =Δ++,Δ+,Δ0) utilized in the so-called type-II seesaw model to explain the lightness of neutrinos, would generate nonstandard interactions (NSI) for a neutrino propagating in matter. We investigate the prospects to probe these interactions in long baseline neutrino oscillation experiments. We analyze the upper bounds that the proposed DUNE experiment might set on the nonstandard parameters and numerically derive upper bounds, as a function of the lightest neutrino mass, on the ratio the mass MΔ of the triplet scalars, and the strength |λϕ| of the coupling ϕ ϕ Δ of the triplet Δ and conventional Higgs doublet ϕ . We also discuss the possible misinterpretation of these effects as effects arising from a nonunitarity of the neutrino mixing matrix and compare the results with the bounds that arise from the charged lepton flavor violating processes.

Estimates on Functional Integrals of Quantum Mechanics and Non-relativistic Quantum Field Theory

NASA Astrophysics Data System (ADS)

Bley, Gonzalo A.; Thomas, Lawrence E.

2017-01-01

We provide a unified method for obtaining upper bounds for certain functional integrals appearing in quantum mechanics and non-relativistic quantum field theory, functionals of the form {E[{exp}(A_T)]} , the (effective) action {A_T} being a function of particle trajectories up to time T. The estimates in turn yield rigorous lower bounds for ground state energies, via the Feynman-Kac formula. The upper bounds are obtained by writing the action for these functional integrals in terms of stochastic integrals. The method is illustrated in familiar quantum mechanical settings: for the hydrogen atom, for a Schrödinger operator with {1/|x|^2} potential with small coupling, and, with a modest adaptation of the method, for the harmonic oscillator. We then present our principal applications of the method, in the settings of non-relativistic quantum field theories for particles moving in a quantized Bose field, including the optical polaron and Nelson models.

Dwell time-based stabilisation of switched delay systems using free-weighting matrices

NASA Astrophysics Data System (ADS)

Koru, Ahmet Taha; Delibaşı, Akın; Özbay, Hitay

2018-01-01

In this paper, we present a quasi-convex optimisation method to minimise an upper bound of the dwell time for stability of switched delay systems. Piecewise Lyapunov-Krasovskii functionals are introduced and the upper bound for the derivative of Lyapunov functionals is estimated by free-weighting matrices method to investigate non-switching stability of each candidate subsystems. Then, a sufficient condition for the dwell time is derived to guarantee the asymptotic stability of the switched delay system. Once these conditions are represented by a set of linear matrix inequalities , dwell time optimisation problem can be formulated as a standard quasi-convex optimisation problem. Numerical examples are given to illustrate the improvements over previously obtained dwell time bounds. Using the results obtained in the stability case, we present a nonlinear minimisation algorithm to synthesise the dwell time minimiser controllers. The algorithm solves the problem with successive linearisation of nonlinear conditions.

Decay of superconducting correlations for gauged electrons in dimensions D ≤ 4

NASA Astrophysics Data System (ADS)

Tada, Yasuhiro; Koma, Tohru

2018-03-01

We study lattice superconductors coupled to gauge fields, such as an attractive Hubbard model in electromagnetic fields, with a standard gauge fixing. We prove upper bounds for a two-point Cooper pair correlation at finite temperatures in spatial dimensions D ≤ 4. The upper bounds decay exponentially in three dimensions and by power law in four dimensions. These imply the absence of the superconducting long-range order for the Cooper pair amplitude as a consequence of fluctuations of the gauge fields. Since our results hold for the gauge fixing Hamiltonian, they cannot be obtained as a corollary of Elitzur's theorem.

Calculations of reliability predictions for the Apollo spacecraft

NASA Technical Reports Server (NTRS)

Amstadter, B. L.

1966-01-01

A new method of reliability prediction for complex systems is defined. Calculation of both upper and lower bounds are involved, and a procedure for combining the two to yield an approximately true prediction value is presented. Both mission success and crew safety predictions can be calculated, and success probabilities can be obtained for individual mission phases or subsystems. Primary consideration is given to evaluating cases involving zero or one failure per subsystem, and the results of these evaluations are then used for analyzing multiple failure cases. Extensive development is provided for the overall mission success and crew safety equations for both the upper and lower bounds.

A proof of the log-concavity conjecture related to the computation of the ergodic capacity of MIMO channels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gurvitis, Leonid

2009-01-01

An upper bound on the ergodic capacity of MIMO channels was introduced recently in [1]. This upper bound amounts to the maximization on the simplex of some multilinear polynomial p({lambda}{sub 1}, ..., {lambda}{sub n}) with non-negative coefficients. In general, such maximizations problems are NP-HARD. But if say, the functional log(p) is concave on the simplex and can be efficiently evaluated, then the maximization can also be done efficiently. Such log-concavity was conjectured in [1]. We give in this paper self-contained proof of the conjecture, based on the theory of H-Stable polynomials.

Investigation of matter-antimatter interaction for possible propulsion applications

NASA Technical Reports Server (NTRS)

Morgan, D. L., Jr.

1974-01-01

Matter-antimatter annihilation is discussed as a means of rocket propulsion. The feasibility of different means of antimatter storage is shown to depend on how annihilation rates are affected by various circumstances. The annihilation processes are described, with emphasis on important features of atom-antiatom interatomic potential energies. A model is developed that allows approximate calculation of upper and lower bounds to the interatomic potential energy for any atom-antiatom pair. Formulae for the upper and lower bounds for atom-antiatom annihilation cross-sections are obtained and applied to the annihilation rates for each means of antimatter storage under consideration. Recommendations for further studies are presented.

Marginal Consistency: Upper-Bounding Partition Functions over Commutative Semirings.

PubMed

Werner, Tomás

2015-07-01

Many inference tasks in pattern recognition and artificial intelligence lead to partition functions in which addition and multiplication are abstract binary operations forming a commutative semiring. By generalizing max-sum diffusion (one of convergent message passing algorithms for approximate MAP inference in graphical models), we propose an iterative algorithm to upper bound such partition functions over commutative semirings. The iteration of the algorithm is remarkably simple: change any two factors of the partition function such that their product remains the same and their overlapping marginals become equal. In many commutative semirings, repeating this iteration for different pairs of factors converges to a fixed point when the overlapping marginals of every pair of factors coincide. We call this state marginal consistency. During that, an upper bound on the partition function monotonically decreases. This abstract algorithm unifies several existing algorithms, including max-sum diffusion and basic constraint propagation (or local consistency) algorithms in constraint programming. We further construct a hierarchy of marginal consistencies of increasingly higher levels and show than any such level can be enforced by adding identity factors of higher arity (order). Finally, we discuss instances of the framework for several semirings, including the distributive lattice and the max-sum and sum-product semirings.

On the Role of Entailment Patterns and Scalar Implicatures in the Processing of Numerals

ERIC Educational Resources Information Center

Panizza, Daniele; Chierchia, Gennaro; Clifton, Charles, Jr.

2009-01-01

There has been much debate, in both the linguistics and the psycholinguistics literature, concerning numbers and the interpretation of number denoting determiners ("numerals"). Such debate concerns, in particular, the nature and distribution of upper-bounded ("exact") interpretations vs. lower-bounded ("at-least") construals. In the present paper…

Sublinear Upper Bounds for Stochastic Programs with Recourse. Revision.

DTIC Science & Technology

1987-06-01

approximation procedures for (1.1) generally rely on discretizations of E (Huang, Ziemba , and Ben-Tal (1977), Kall and Stoyan (1982), Birge and Wets...Wright, Practical optimization (Academic Press, London and New York,1981). C.C. Huang, W. Ziemba , and A. Ben-Tal, "Bounds on the expectation of a con

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zachos, C. K.; High Energy Physics

Following ref [1], a classical upper bound for quantum entropy is identified and illustrated, 0 {le} S{sub q} {le} ln (e{sigma}{sup 2}/2{h_bar}), involving the variance {sigma}{sup 2} in phase space of the classical limit distribution of a given system. A fortiori, this further bounds the corresponding information-theoretical generalizations of the quantum entropy proposed by Renyi.

Representing and Acquiring Geographic Knowledge.

DTIC Science & Technology

1984-01-01

which is allowed if v is a kowledge bound of REG. e3. The real vertices of a clump map into the boundary of the corresponding object so * , 21...example, *What is the diameter of the pond?" can be answered, but the answer will, in general, be a range power -bound, upper-bound]. If the clump for...cases of others. They are included separately, because their procedures are either faster or more powerful than the general procedure. I will not

A Posteriori Finite Element Bounds for Sensitivity Derivatives of Partial-Differential-Equation Outputs. Revised

NASA Technical Reports Server (NTRS)

Lewis, Robert Michael; Patera, Anthony T.; Peraire, Jaume

1998-01-01

We present a Neumann-subproblem a posteriori finite element procedure for the efficient and accurate calculation of rigorous, 'constant-free' upper and lower bounds for sensitivity derivatives of functionals of the solutions of partial differential equations. The design motivation for sensitivity derivative error control is discussed; the a posteriori finite element procedure is described; the asymptotic bounding properties and computational complexity of the method are summarized; and illustrative numerical results are presented.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Müller-Hermes, Alexander, E-mail: muellerh@ma.tum.de; Wolf, Michael M., E-mail: m.wolf@tum.de; Reeb, David, E-mail: reeb.qit@gmail.com

We investigate linear maps between matrix algebras that remain positive under tensor powers, i.e., under tensoring with n copies of themselves. Completely positive and completely co-positive maps are trivial examples of this kind. We show that for every n ∈ ℕ, there exist non-trivial maps with this property and that for two-dimensional Hilbert spaces there is no non-trivial map for which this holds for all n. For higher dimensions, we reduce the existence question of such non-trivial “tensor-stable positive maps” to a one-parameter family of maps and show that an affirmative answer would imply the existence of non-positive partial transposemore » bound entanglement. As an application, we show that any tensor-stable positive map that is not completely positive yields an upper bound on the quantum channel capacity, which for the transposition map gives the well-known cb-norm bound. We, furthermore, show that the latter is an upper bound even for the local operations and classical communications-assisted quantum capacity, and that moreover it is a strong converse rate for this task.« less

Numerical simulation for horizontal subsurface flow constructed wetlands: A short review including geothermal effects and solution bounding in biodegradation procedures

NASA Astrophysics Data System (ADS)

Liolios, K.; Tsihrintzis, V.; Angelidis, P.; Georgiev, K.; Georgiev, I.

2016-10-01

Current developments on modeling of groundwater flow and contaminant transport and removal in the porous media of Horizontal Subsurface Flow Constructed Wetlands (HSF CWs) are first reviewed in a short way. The two usual environmental engineering approaches, the black-box and the process-based one, are briefly presented. Next, recent research results obtained by using these two approaches are briefly discussed as application examples, where emphasis is given to the evaluation of the optimal design and operation parameters concerning HSF CWs. For the black-box approach, the use of Artificial Neural Networks is discussed for the formulation of models, which predict the removal performance of HSF CWs. A novel mathematical prove is presented, which concerns the dependence of the first-order removal coefficient on the Temperature and the Hydraulic Residence Time. For the process-based approach, an application example is first discussed which concerns procedures to evaluate the optimal range of values for the removal coefficient, dependent on either the Temperature or the Hydraulic Residence Time. This evaluation is based on simulating available experimental results of pilot-scale units operated in Democritus University of Thrace, Xanthi, Greece. Further, in a second example, a novel enlargement of the system of Partial Differential Equations is presented, in order to include geothermal effects. Finally, in a third example, the case of parameters uncertainty concerning biodegradation procedures is considered and the use of upper and a novel approach is presented, which concerns the upper and the lower solution bound for the practical draft design of HSF CWs.

Measures and limits of models of fixation selection.

PubMed

Wilming, Niklas; Betz, Torsten; Kietzmann, Tim C; König, Peter

2011-01-01

Models of fixation selection are a central tool in the quest to understand how the human mind selects relevant information. Using this tool in the evaluation of competing claims often requires comparing different models' relative performance in predicting eye movements. However, studies use a wide variety of performance measures with markedly different properties, which makes a comparison difficult. We make three main contributions to this line of research: First we argue for a set of desirable properties, review commonly used measures, and conclude that no single measure unites all desirable properties. However the area under the ROC curve (a classification measure) and the KL-divergence (a distance measure of probability distributions) combine many desirable properties and allow a meaningful comparison of critical model performance. We give an analytical proof of the linearity of the ROC measure with respect to averaging over subjects and demonstrate an appropriate correction of entropy-based measures like KL-divergence for small sample sizes in the context of eye-tracking data. Second, we provide a lower bound and an upper bound of these measures, based on image-independent properties of fixation data and between subject consistency respectively. Based on these bounds it is possible to give a reference frame to judge the predictive power of a model of fixation selection. We provide open-source python code to compute the reference frame. Third, we show that the upper, between subject consistency bound holds only for models that predict averages of subject populations. Departing from this we show that incorporating subject-specific viewing behavior can generate predictions which surpass that upper bound. Taken together, these findings lay out the required information that allow a well-founded judgment of the quality of any model of fixation selection and should therefore be reported when a new model is introduced.

Randomized noninferiority trial of telephone versus in-person genetic counseling for hereditary breast and ovarian cancer.

PubMed

Schwartz, Marc D; Valdimarsdottir, Heiddis B; Peshkin, Beth N; Mandelblatt, Jeanne; Nusbaum, Rachel; Huang, An-Tsun; Chang, Yaojen; Graves, Kristi; Isaacs, Claudine; Wood, Marie; McKinnon, Wendy; Garber, Judy; McCormick, Shelley; Kinney, Anita Y; Luta, George; Kelleher, Sarah; Leventhal, Kara-Grace; Vegella, Patti; Tong, Angie; King, Lesley

2014-03-01

Although guidelines recommend in-person counseling before BRCA1/BRCA2 gene testing, genetic counseling is increasingly offered by telephone. As genomic testing becomes more common, evaluating alternative delivery approaches becomes increasingly salient. We tested whether telephone delivery of BRCA1/2 genetic counseling was noninferior to in-person delivery. Participants (women age 21 to 85 years who did not have newly diagnosed or metastatic cancer and lived within a study site catchment area) were randomly assigned to usual care (UC; n = 334) or telephone counseling (TC; n = 335). UC participants received in-person pre- and post-test counseling; TC participants completed all counseling by telephone. Primary outcomes were knowledge, satisfaction, decision conflict, distress, and quality of life; secondary outcomes were equivalence of BRCA1/2 test uptake and costs of delivering TC versus UC. TC was noninferior to UC on all primary outcomes. At 2 weeks after pretest counseling, knowledge (d = 0.03; lower bound of 97.5% CI, -0.61), perceived stress (d = -0.12; upper bound of 97.5% CI, 0.21), and satisfaction (d = -0.16; lower bound of 97.5% CI, -0.70) had group differences and confidence intervals that did not cross their 1-point noninferiority limits. Decision conflict (d = 1.1; upper bound of 97.5% CI, 3.3) and cancer distress (d = -1.6; upper bound of 97.5% CI, 0.27) did not cross their 4-point noninferiority limit. Results were comparable at 3 months. TC was not equivalent to UC on BRCA1/2 test uptake (UC, 90.1%; TC, 84.2%). TC yielded cost savings of $114 per patient. Genetic counseling can be effectively and efficiently delivered via telephone to increase access and decrease costs.

Sign rank versus Vapnik-Chervonenkis dimension

NASA Astrophysics Data System (ADS)

Alon, N.; Moran, Sh; Yehudayoff, A.

2017-12-01

This work studies the maximum possible sign rank of sign (N × N)-matrices with a given Vapnik-Chervonenkis dimension d. For d=1, this maximum is three. For d=2, this maximum is \\widetilde{\\Theta}(N1/2). For d >2, similar but slightly less accurate statements hold. The lower bounds improve on previous ones by Ben-David et al., and the upper bounds are novel. The lower bounds are obtained by probabilistic constructions, using a theorem of Warren in real algebraic topology. The upper bounds are obtained using a result of Welzl about spanning trees with low stabbing number, and using the moment curve. The upper bound technique is also used to: (i) provide estimates on the number of classes of a given Vapnik-Chervonenkis dimension, and the number of maximum classes of a given Vapnik-Chervonenkis dimension--answering a question of Frankl from 1989, and (ii) design an efficient algorithm that provides an O(N/log(N)) multiplicative approximation for the sign rank. We also observe a general connection between sign rank and spectral gaps which is based on Forster's argument. Consider the adjacency (N × N)-matrix of a Δ-regular graph with a second eigenvalue of absolute value λ and Δ ≤ N/2. We show that the sign rank of the signed version of this matrix is at least Δ/λ. We use this connection to prove the existence of a maximum class C\\subseteq\\{+/- 1\\}^N with Vapnik-Chervonenkis dimension 2 and sign rank \\widetilde{\\Theta}(N1/2). This answers a question of Ben-David et al. regarding the sign rank of large Vapnik-Chervonenkis classes. We also describe limitations of this approach, in the spirit of the Alon-Boppana theorem. We further describe connections to communication complexity, geometry, learning theory, and combinatorics. Bibliography: 69 titles.

A formulation of a matrix sparsity approach for the quantum ordered search algorithm

NASA Astrophysics Data System (ADS)

Parmar, Jupinder; Rahman, Saarim; Thiara, Jaskaran

One specific subset of quantum algorithms is Grovers Ordered Search Problem (OSP), the quantum counterpart of the classical binary search algorithm, which utilizes oracle functions to produce a specified value within an ordered database. Classically, the optimal algorithm is known to have a log2N complexity; however, Grovers algorithm has been found to have an optimal complexity between the lower bound of ((lnN-1)/π≈0.221log2N) and the upper bound of 0.433log2N. We sought to lower the known upper bound of the OSP. With Farhi et al. MITCTP 2815 (1999), arXiv:quant-ph/9901059], we see that the OSP can be resolved into a translational invariant algorithm to create quantum query algorithm restraints. With these restraints, one can find Laurent polynomials for various k — queries — and N — database sizes — thus finding larger recursive sets to solve the OSP and effectively reducing the upper bound. These polynomials are found to be convex functions, allowing one to make use of convex optimization to find an improvement on the known bounds. According to Childs et al. [Phys. Rev. A 75 (2007) 032335], semidefinite programming, a subset of convex optimization, can solve the particular problem represented by the constraints. We were able to implement a program abiding to their formulation of a semidefinite program (SDP), leading us to find that it takes an immense amount of storage and time to compute. To combat this setback, we then formulated an approach to improve results of the SDP using matrix sparsity. Through the development of this approach, along with an implementation of a rudimentary solver, we demonstrate how matrix sparsity reduces the amount of time and storage required to compute the SDP — overall ensuring further improvements will likely be made to reach the theorized lower bound.

Sample Complexity Bounds for Differentially Private Learning

PubMed Central

Chaudhuri, Kamalika; Hsu, Daniel

2013-01-01

This work studies the problem of privacy-preserving classification – namely, learning a classifier from sensitive data while preserving the privacy of individuals in the training set. In particular, the learning algorithm is required in this problem to guarantee differential privacy, a very strong notion of privacy that has gained significant attention in recent years. A natural question to ask is: what is the sample requirement of a learning algorithm that guarantees a certain level of privacy and accuracy? We address this question in the context of learning with infinite hypothesis classes when the data is drawn from a continuous distribution. We first show that even for very simple hypothesis classes, any algorithm that uses a finite number of examples and guarantees differential privacy must fail to return an accurate classifier for at least some unlabeled data distributions. This result is unlike the case with either finite hypothesis classes or discrete data domains, in which distribution-free private learning is possible, as previously shown by Kasiviswanathan et al. (2008). We then consider two approaches to differentially private learning that get around this lower bound. The first approach is to use prior knowledge about the unlabeled data distribution in the form of a reference distribution chosen independently of the sensitive data. Given such a reference , we provide an upper bound on the sample requirement that depends (among other things) on a measure of closeness between and the unlabeled data distribution. Our upper bound applies to the non-realizable as well as the realizable case. The second approach is to relax the privacy requirement, by requiring only label-privacy – namely, that the only labels (and not the unlabeled parts of the examples) be considered sensitive information. An upper bound on the sample requirement of learning with label privacy was shown by Chaudhuri et al. (2006); in this work, we show a lower bound. PMID:25285183

Extending Landauer's bound from bit erasure to arbitrary computation

NASA Astrophysics Data System (ADS)

Wolpert, David

The minimal thermodynamic work required to erase a bit, known as Landauer's bound, has been extensively investigated both theoretically and experimentally. However, when viewed as a computation that maps inputs to outputs, bit erasure has a very special property: the output does not depend on the input. Existing analyses of thermodynamics of bit erasure implicitly exploit this property, and thus cannot be directly extended to analyze the computation of arbitrary input-output maps. Here we show how to extend these earlier analyses of bit erasure to analyze the thermodynamics of arbitrary computations. Doing this establishes a formal connection between the thermodynamics of computers and much of theoretical computer science. We use this extension to analyze the thermodynamics of the canonical ``general purpose computer'' considered in computer science theory: a universal Turing machine (UTM). We consider a UTM which maps input programs to output strings, where inputs are drawn from an ensemble of random binary sequences, and prove: i) The minimal work needed by a UTM to run some particular input program X and produce output Y is the Kolmogorov complexity of Y minus the log of the ``algorithmic probability'' of Y. This minimal amount of thermodynamic work has a finite upper bound, which is independent of the output Y, depending only on the details of the UTM. ii) The expected work needed by a UTM to compute some given output Y is infinite. As a corollary, the overall expected work to run a UTM is infinite. iii) The expected work needed by an arbitrary Turing machine T (not necessarily universal) to compute some given output Y can either be infinite or finite, depending on Y and the details of T. To derive these results we must combine ideas from nonequilibrium statistical physics with fundamental results from computer science, such as Levin's coding theorem and other theorems about universal computation. I would like to ackowledge the Santa Fe Institute, Grant No. TWCF0079/AB47 from the Templeton World Charity Foundation, Grant No. FQXi-RHl3-1349 from the FQXi foundation, and Grant No. CHE-1648973 from the U.S. National Science Foundation.

Spread of entanglement and causality

NASA Astrophysics Data System (ADS)

Casini, Horacio; Liu, Hong; Mezei, Márk

2016-07-01

We investigate causality constraints on the time evolution of entanglement entropy after a global quench in relativistic theories. We first provide a general proof that the so-called tsunami velocity is bounded by the speed of light. We then generalize the free particle streaming model of [1] to general dimensions and to an arbitrary entanglement pattern of the initial state. In more than two spacetime dimensions the spread of entanglement in these models is highly sensitive to the initial entanglement pattern, but we are able to prove an upper bound on the normalized rate of growth of entanglement entropy, and hence the tsunami velocity. The bound is smaller than what one gets for quenches in holographic theories, which highlights the importance of interactions in the spread of entanglement in many-body systems. We propose an interacting model which we believe provides an upper bound on the spread of entanglement for interacting relativistic theories. In two spacetime dimensions with multiple intervals, this model and its variations are able to reproduce intricate results exhibited by holographic theories for a significant part of the parameter space. For higher dimensions, the model bounds the tsunami velocity at the speed of light. Finally, we construct a geometric model for entanglement propagation based on a tensor network construction for global quenches.

Ion wake field effects on the dust-ion-acoustic surface mode in a semi-bounded Lorentzian dusty plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Myoung-Jae; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr; Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180-3590

The dispersion relation for the dust ion-acoustic surface waves propagating at the interface of semi-bounded Lorentzian dusty plasma with supersonic ion flow has been kinetically derived to investigate the nonthermal property and the ion wake field effect. We found that the supersonic ion flow creates the upper and the lower modes. The increase in the nonthermal particles decreases the wave frequency for the upper mode whereas it increases the frequency for the lower mode. The increase in the supersonic ion flow velocity is found to enhance the wave frequency for both modes. We also found that the increase in nonthermalmore » plasmas is found to enhance the group velocity of the upper mode. However, the nonthermal particles suppress the lower mode group velocity. The nonthermal effects on the group velocity will be reduced in the limit of small or large wavelength limit.« less

Dark energy and extended dark matter halos

NASA Astrophysics Data System (ADS)

Chernin, A. D.; Teerikorpi, P.; Valtonen, M. J.; Dolgachev, V. P.; Domozhilova, L. M.; Byrd, G. G.

2012-03-01

The cosmological mean matter (dark and baryonic) density measured in the units of the critical density is Ωm = 0.27. Independently, the local mean density is estimated to be Ωloc = 0.08-0.23 from recent data on galaxy groups at redshifts up to z = 0.01-0.03 (as published by Crook et al. 2007, ApJ, 655, 790 and Makarov & Karachentsev 2011, MNRAS, 412, 2498). If the lower values of Ωloc are reliable, as Makarov & Karachentsev and some other observers prefer, does this mean that the Local Universe of 100-300 Mpc across is an underdensity in the cosmic matter distribution? Or could it nevertheless be representative of the mean cosmic density or even be an overdensity due to the Local Supercluster therein. We focus on dark matter halos of groups of galaxies and check how much dark mass the invisible outer layers of the halos are able to host. The outer layers are usually devoid of bright galaxies and cannot be seen at large distances. The key factor which bounds the size of an isolated halo is the local antigravity produced by the omnipresent background of dark energy. A gravitationally bound halo does not extend beyond the zero-gravity surface where the gravity of matter and the antigravity of dark energy balance, thus defining a natural upper size of a system. We use our theory of local dynamical effects of dark energy to estimate the maximal sizes and masses of the extended dark halos. Using data from three recent catalogs of galaxy groups, we show that the calculated mass bounds conform with the assumption that a significant amount of dark matter is located in the invisible outer parts of the extended halos, sufficient to fill the gap between the observed and expected local matter density. Nearby groups of galaxies and the Virgo cluster have dark halos which seem to extend up to their zero-gravity surfaces. If the extended halo is a common feature of gravitationally bound systems on scales of galaxy groups and clusters, the Local Universe could be typical or even an overdense region, with a low density contrast ~1.

Bounding the solutions of parametric weakly coupled second-order semilinear parabolic partial differential equations

DOE PAGES

Azunre, P.

2016-09-21

Here in this paper, two novel techniques for bounding the solutions of parametric weakly coupled second-order semilinear parabolic partial differential equations are developed. The first provides a theorem to construct interval bounds, while the second provides a theorem to construct lower bounds convex and upper bounds concave in the parameter. The convex/concave bounds can be significantly tighter than the interval bounds because of the wrapping effect suffered by interval analysis in dynamical systems. Both types of bounds are computationally cheap to construct, requiring solving auxiliary systems twice and four times larger than the original system, respectively. An illustrative numerical examplemore » of bound construction and use for deterministic global optimization within a simple serial branch-and-bound algorithm, implemented numerically using interval arithmetic and a generalization of McCormick's relaxation technique, is presented. Finally, problems within the important class of reaction-diffusion systems may be optimized with these tools.« less

Bounds on quantum confinement effects in metal nanoparticles

NASA Astrophysics Data System (ADS)

Blackman, G. Neal; Genov, Dentcho A.

2018-03-01

Quantum size effects on the permittivity of metal nanoparticles are investigated using the quantum box model. Explicit upper and lower bounds are derived for the permittivity and relaxation rates due to quantum confinement effects. These bounds are verified numerically, and the size dependence and frequency dependence of the empirical Drude size parameter is extracted from the model. Results suggest that the common practice of empirically modifying the dielectric function can lead to inaccurate predictions for highly uniform distributions of finite-sized particles.

Fixed-Time Outer Synchronization of Complex Networks with Noise Coupling

NASA Astrophysics Data System (ADS)

Shi, Hong-Jun; Miao, Lian-Ying; Sun, Yong-Zheng; Liu, Mao-Xing

2018-03-01

In this paper, the fixed-time outer synchronization of complex networks with noise coupling is investigated. Based on the theory of fixed-time stability and matrix inequalities, sufficient conditions for fixed-time outer synchronization are established and the estimation of the upper bound of the setting time is obtained. The result shows that the setting time can be adjusted to a desired value regardless of the initial states. Numerical simulations are performed to verify the effectiveness of the theoretical results. The effects of control parameters and the density of controlled nodes on the converging time are studied. Supported by the National Natural Science Foundation of China under Grant Nos. 11711530203 and 11771443, and the Fundamental Research Funds for the Central Universities under Grant No. 2015XKMS076

Stability of a Unitary Bose Gas

NASA Astrophysics Data System (ADS)

Fletcher, Richard J.; Gaunt, Alexander L.; Navon, Nir; Smith, Robert P.; Hadzibabic, Zoran

2013-09-01

We study the stability of a thermal K39 Bose gas across a broad Feshbach resonance, focusing on the unitary regime, where the scattering length a exceeds the thermal wavelength λ. We measure the general scaling laws relating the particle-loss and heating rates to the temperature, scattering length, and atom number. Both at unitarity and for positive a≪λ we find agreement with three-body theory. However, for a<0 and away from unitarity, we observe significant four-body decay. At unitarity, the three-body loss coefficient, L3∝λ4, is 3 times lower than the universal theoretical upper bound. This reduction is a consequence of species-specific Efimov physics and makes K39 particularly promising for studies of many-body physics in a unitary Bose gas.

Localization of the eigenvalues of linear integral equations with applications to linear ordinary differential equations.

NASA Technical Reports Server (NTRS)

Sloss, J. M.; Kranzler, S. K.

1972-01-01

The equivalence of a considered integral equation form with an infinite system of linear equations is proved, and the localization of the eigenvalues of the infinite system is expressed. Error estimates are derived, and the problems of finding upper bounds and lower bounds for the eigenvalues are solved simultaneously.

The Limits of Coding with Joint Constraints on Detected and Undetected Error Rates

NASA Technical Reports Server (NTRS)

Dolinar, Sam; Andrews, Kenneth; Pollara, Fabrizio; Divsalar, Dariush

2008-01-01

We develop a remarkably tight upper bound on the performance of a parameterized family of bounded angle maximum-likelihood (BA-ML) incomplete decoders. The new bound for this class of incomplete decoders is calculated from the code's weight enumerator, and is an extension of Poltyrev-type bounds developed for complete ML decoders. This bound can also be applied to bound the average performance of random code ensembles in terms of an ensemble average weight enumerator. We also formulate conditions defining a parameterized family of optimal incomplete decoders, defined to minimize both the total codeword error probability and the undetected error probability for any fixed capability of the decoder to detect errors. We illustrate the gap between optimal and BA-ML incomplete decoding via simulation of a small code.

Multi-soliton interaction of a generalized Schrödinger-Boussinesq system in a magnetized plasma

NASA Astrophysics Data System (ADS)

Zhao, Xue-Hui; Tian, Bo; Chai, Jun; Wu, Xiao-Yu; Guo, Yong-Jiang

2017-04-01

Under investigation in this paper is a generalized Schrödinger-Boussinesq system, which describes the stationary propagation of coupled upper-hybrid waves and magnetoacoustic waves in a magnetized plasma. Bilinear forms, one-, two- and three-soliton solutions are derived by virtue of the Hirota method and symbolic computation. Propagation and interaction for the solitons are illustrated graphically: Coefficients β1^{} and β2^{} can affect the velocities and propagation directions of the solitary waves. Amplitude, velocity and shape of the one solitary wave keep invariant during the propagation, implying that the transport of the energy is stable in the upper-hybrid and magnetoacoustic waves, and amplitude of the upper-hybrid wave is bigger than that of the magnetoacoustic wave. For the upper-hybrid and magnetoacoustic waves, head-on, overtaking and bound-state interaction between the two solitary waves are asymptotically depicted, respectively, indicating that the interaction between the two solitary waves is elastic. Elastic interaction between the bound-state soliton and a single one soliton is also displayed, and interaction among the three solitary waves is all elastic.

On the Coriolis effect in acoustic waveguides.

PubMed

Wegert, Henry; Reindl, Leonard M; Ruile, Werner; Mayer, Andreas P

2012-05-01

Rotation of an elastic medium gives rise to a shift of frequency of its acoustic modes, i.e., the time-period vibrations that exist in it. This frequency shift is investigated by applying perturbation theory in the regime of small ratios of the rotation velocity and the frequency of the acoustic mode. In an expansion of the relative frequency shift in powers of this ratio, upper bounds are derived for the first-order and the second-order terms. The derivation of the theoretical upper bounds of the first-order term is presented for linear vibration modes as well as for stable nonlinear vibrations with periodic time dependence that can be represented by a Fourier series.

Asymptotics of the evolution semigroup associated with a scalar field in the presence of a non-linear electromagnetic field

NASA Astrophysics Data System (ADS)

Albeverio, Sergio; Tamura, Hiroshi

2018-04-01

We consider a model describing the coupling of a vector-valued and a scalar homogeneous Markovian random field over R4, interpreted as expressing the interaction between a charged scalar quantum field coupled with a nonlinear quantized electromagnetic field. Expectations of functionals of the random fields are expressed by Brownian bridges. Using this, together with Feynman-Kac-Itô type formulae and estimates on the small time and large time behaviour of Brownian functionals, we prove asymptotic upper and lower bounds on the kernel of the transition semigroup for our model. The upper bound gives faster than exponential decay for large distances of the corresponding resolvent (propagator).

The upper bounds of reduced axial and shear moduli in cross-ply laminates with matrix cracks

NASA Technical Reports Server (NTRS)

Lee, Jong-Won; Allen, D. H.; Harris, C. E.

1991-01-01

The present study proposes a mathematical model utilizing the internal state variable concept for predicting the upper bounds of the reduced axial and shear stiffnesses in cross-ply laminates with matrix cracks. The displacement components at the matrix crack surfaces are explicitly expressed in terms of the observable axial and shear strains and the undamaged material properties. The reduced axial and shear stiffnesses are predicted for glass/epoxy and graphite/epoxy laminates. Comparison of the model with other theoretical and experimental studies is also presented to confirm direct applicability of the model to angle-ply laminates with matrix cracks subjected to general in-plane loading.

SURE reliability analysis: Program and mathematics

NASA Technical Reports Server (NTRS)

Butler, Ricky W.; White, Allan L.

1988-01-01

The SURE program is a new reliability analysis tool for ultrareliable computer system architectures. The computational methods on which the program is based provide an efficient means for computing accurate upper and lower bounds for the death state probabilities of a large class of semi-Markov models. Once a semi-Markov model is described using a simple input language, the SURE program automatically computes the upper and lower bounds on the probability of system failure. A parameter of the model can be specified as a variable over a range of values directing the SURE program to perform a sensitivity analysis automatically. This feature, along with the speed of the program, makes it especially useful as a design tool.

Right-handed neutrino dark matter in left-right symmetric models

NASA Astrophysics Data System (ADS)

Bhupal Dev, P. S.; Mohapatra, Rabindra N.; Zhang, Yongchao

2017-07-01

We show that in a class of non-supersymmetric left-right extensions of the Standard Model (SM), the lightest right-handed neutrino (RHN) is naturally stable and can therefore play the role of thermal Dark Matter (DM) in the Universe for a wide mass range from TeV to PeV. Our model is based on the gauge group SU(3) c × SU(2) L × SU(2) R × U(1) YL × U(1) YR in which a heavy copy of the SM fermions are introduced and the stability of the RHN DM is guaranteed by an automatic Z 2 symmetry present in the leptonic sector. The active neutrino masses in the model arise from the type-II seesaw mechanism. We find a lower bound on the RHN DM mass of order TeV from relic density constraints, as well as an unitarity upper bound in the multi-TeV to PeV scale, depending on the entropy dilution factor. The RHN DM could be made long-lived by soft-breaking of the Z 2 symmetry and provides a concrete example of decaying DM interpretation of the PeV neutrinos observed at IceCube.

Highly accurate bound state calculations of the two-center molecular ions by using the universal variational expansion for three-body systems

NASA Astrophysics Data System (ADS)

Frolov, Alexei M.

2018-03-01

The universal variational expansion for the non-relativistic three-body systems is explicitly constructed. This universal expansion can be used to perform highly accurate numerical computations of the bound state spectra in various three-body systems, including Coulomb three-body systems with arbitrary particle masses and electric charges. Our main interest is related to the adiabatic three-body systems which contain one bound electron and two heavy nuclei of hydrogen isotopes: the protium p, deuterium d and tritium t. We also consider the analogous (model) hydrogen ion ∞H2+ with the two infinitely heavy nuclei.

(Pre-) calibration of a Reduced Complexity Model of the Antarctic Contribution to Sea-level Changes

NASA Astrophysics Data System (ADS)

Ruckert, K. L.; Guan, Y.; Shaffer, G.; Forest, C. E.; Keller, K.

2015-12-01

(Pre-) calibration of a Reduced Complexity Model of the Antarctic Contribution to Sea-level ChangesKelsey L. Ruckert1*, Yawen Guan2, Chris E. Forest1,3,7, Gary Shaffer 4,5,6, and Klaus Keller1,7,81 Department of Geosciences, The Pennsylvania State University, University Park, Pennsylvania, USA 2 Department of Statistics, The Pennsylvania State University, University Park, Pennsylvania, USA 3 Department of Meteorology, The Pennsylvania State University, University Park, Pennsylvania, USA 4 GAIA_Antarctica, University of Magallanes, Punta Arenas, Chile 5 Center for Advanced Studies in Arid Zones, La Serena, Chile 6 Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark 7 Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, Pennsylvania, USA 8 Department of Engineering and Public Policy, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA * Corresponding author. E-mail klr324@psu.eduUnderstanding and projecting future sea-level changes poses nontrivial challenges. Sea-level changes are driven primarily by changes in the density of seawater as well as changes in the size of glaciers and ice sheets. Previous studies have demonstrated that a key source of uncertainties surrounding sea-level projections is the response of the Antarctic ice sheet to warming temperatures. Here we calibrate a previously published and relatively simple model of the Antarctic ice sheet over a hindcast period from the last interglacial period to the present. We apply and compare a range of (pre-) calibration methods, including a Bayesian approach that accounts for heteroskedasticity. We compare the model hindcasts and projections for different levels of model complexity and calibration methods. We compare the projections with the upper bounds from previous studies and find our projections have a narrower range in 2100. Furthermore we discuss the implications for the design of climate risk management strategies.

Constraining the generalized uncertainty principle with the atomic weak-equivalence-principle test

NASA Astrophysics Data System (ADS)

Gao, Dongfeng; Wang, Jin; Zhan, Mingsheng

2017-04-01

Various models of quantum gravity imply the Planck-scale modifications of Heisenberg's uncertainty principle into a so-called generalized uncertainty principle (GUP). The GUP effects on high-energy physics, cosmology, and astrophysics have been extensively studied. Here, we focus on the weak-equivalence-principle (WEP) violation induced by the GUP. Results from the WEP test with the 85Rb-87Rb dual-species atom interferometer are used to set upper bounds on parameters in two GUP proposals. A 1045-level bound on the Kempf-Mangano-Mann proposal and a 1027-level bound on Maggiore's proposal, which are consistent with bounds from other experiments, are obtained. All these bounds have huge room for improvement in the future.

PubMed

Trinker, Horst

2011-10-28

We study the distribution of triples of codewords of codes and ordered codes. Schrijver [A. Schrijver, New code upper bounds from the Terwilliger algebra and semidefinite programming, IEEE Trans. Inform. Theory 51 (8) (2005) 2859-2866] used the triple distribution of a code to establish a bound on the number of codewords based on semidefinite programming. In the first part of this work, we generalize this approach for ordered codes. In the second part, we consider linear codes and linear ordered codes and present a MacWilliams-type identity for the triple distribution of their dual code. Based on the non-negativity of this linear transform, we establish a linear programming bound and conclude with a table of parameters for which this bound yields better results than the standard linear programming bound.

Validation of the SURE Program, phase 1

NASA Technical Reports Server (NTRS)

Dotson, Kelly J.

1987-01-01

Presented are the results of the first phase in the validation of the SURE (Semi-Markov Unreliability Range Evaluator) program. The SURE program gives lower and upper bounds on the death-state probabilities of a semi-Markov model. With these bounds, the reliability of a semi-Markov model of a fault-tolerant computer system can be analyzed. For the first phase in the validation, fifteen semi-Markov models were solved analytically for the exact death-state probabilities and these solutions compared to the corresponding bounds given by SURE. In every case, the SURE bounds covered the exact solution. The bounds, however, had a tendency to separate in cases where the recovery rate was slow or the fault arrival rate was fast.

The random coding bound is tight for the average code.

NASA Technical Reports Server (NTRS)

Gallager, R. G.

1973-01-01

The random coding bound of information theory provides a well-known upper bound to the probability of decoding error for the best code of a given rate and block length. The bound is constructed by upperbounding the average error probability over an ensemble of codes. The bound is known to give the correct exponential dependence of error probability on block length for transmission rates above the critical rate, but it gives an incorrect exponential dependence at rates below a second lower critical rate. Here we derive an asymptotic expression for the average error probability over the ensemble of codes used in the random coding bound. The result shows that the weakness of the random coding bound at rates below the second critical rate is due not to upperbounding the ensemble average, but rather to the fact that the best codes are much better than the average at low rates.

Scalable L-infinite coding of meshes.

PubMed

Munteanu, Adrian; Cernea, Dan C; Alecu, Alin; Cornelis, Jan; Schelkens, Peter

2010-01-01

The paper investigates the novel concept of local-error control in mesh geometry encoding. In contrast to traditional mesh-coding systems that use the mean-square error as target distortion metric, this paper proposes a new L-infinite mesh-coding approach, for which the target distortion metric is the L-infinite distortion. In this context, a novel wavelet-based L-infinite-constrained coding approach for meshes is proposed, which ensures that the maximum error between the vertex positions in the original and decoded meshes is lower than a given upper bound. Furthermore, the proposed system achieves scalability in L-infinite sense, that is, any decoding of the input stream will correspond to a perfectly predictable L-infinite distortion upper bound. An instantiation of the proposed L-infinite-coding approach is demonstrated for MESHGRID, which is a scalable 3D object encoding system, part of MPEG-4 AFX. In this context, the advantages of scalable L-infinite coding over L-2-oriented coding are experimentally demonstrated. One concludes that the proposed L-infinite mesh-coding approach guarantees an upper bound on the local error in the decoded mesh, it enables a fast real-time implementation of the rate allocation, and it preserves all the scalability features and animation capabilities of the employed scalable mesh codec.

Adaptive nonsingular fast terminal sliding-mode control for the tracking problem of uncertain dynamical systems.

PubMed

Boukattaya, Mohamed; Mezghani, Neila; Damak, Tarak

2018-06-01

In this paper, robust and adaptive nonsingular fast terminal sliding-mode (NFTSM) control schemes for the trajectory tracking problem are proposed with known or unknown upper bound of the system uncertainty and external disturbances. The developed controllers take the advantage of the NFTSM theory to ensure fast convergence rate, singularity avoidance, and robustness against uncertainties and external disturbances. First, a robust NFTSM controller is proposed which guarantees that sliding surface and equilibrium point can be reached in a short finite-time from any initial state. Then, in order to cope with the unknown upper bound of the system uncertainty which may be occurring in practical applications, a new adaptive NFTSM algorithm is developed. One feature of the proposed control law is their adaptation techniques where the prior knowledge of parameters uncertainty and disturbances is not needed. However, the adaptive tuning law can estimate the upper bound of these uncertainties using only position and velocity measurements. Moreover, the proposed controller eliminates the chattering effect without losing the robustness property and the precision. Stability analysis is performed using the Lyapunov stability theory, and simulation studies are conducted to verify the effectiveness of the developed control schemes. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Effects of general relativity on glitch amplitudes and pulsar mass upper bounds

NASA Astrophysics Data System (ADS)

Antonelli, M.; Montoli, A.; Pizzochero, P. M.

2018-04-01

Pinning of vortex lines in the inner crust of a spinning neutron star may be the mechanism that enhances the differential rotation of the internal neutron superfluid, making it possible to freeze some amount of angular momentum which eventually can be released, thus causing a pulsar glitch. We investigate the general relativistic corrections to pulsar glitch amplitudes in the slow-rotation approximation, consistently with the stratified structure of the star. We thus provide a relativistic generalization of a previous Newtonian model that was recently used to estimate upper bounds on the masses of glitching pulsars. We find that the effect of general relativity on the glitch amplitudes obtained by emptying the whole angular momentum reservoir is less than 30 per cent. Moreover, we show that the Newtonian upper bounds on the masses of large glitchers obtained from observations of their maximum recorded event differ by less than a few percent from those calculated within the relativistic framework. This work can also serve as a basis to construct more sophisticated models of angular momentum reservoir in a relativistic context: in particular, we present two alternative scenarios for macroscopically rigid and slack pinned vortex lines, and we generalize the Feynman-Onsager relation to the case when both entrainment coupling between the fluids and a strong axisymmetric gravitational field are present.

A Reduced Basis Method with Exact-Solution Certificates for Symmetric Coercive Equations

DTIC Science & Technology

2013-11-06

the energy associated with the infinite - dimensional weak solution of parametrized symmetric coercive partial differential equations with piecewise...builds bounds with respect to the infinite - dimensional weak solution, aims to entirely remove the issue of the “truth” within the certified reduced basis...framework. We in particular introduce a reduced basis method that provides rigorous upper and lower bounds

The Economic Cost of Methamphetamine Use in the United States, 2005

ERIC Educational Resources Information Center

Nicosia, Nancy; Pacula, Rosalie Liccardo; Kilmer, Beau; Lundberg, Russell; Chiesa, James

2009-01-01

This first national estimate suggests that the economic cost of methamphetamine (meth) use in the United States reached $23.4 billion in 2005. Given the uncertainty in estimating the costs of meth use, this book provides a lower-bound estimate of $16.2 billion and an upper-bound estimate of $48.3 billion. The analysis considers a wide range of…

Curvature Continuous and Bounded Path Planning for Fixed-Wing UAVs

PubMed Central

Jiang, Peng; Li, Deshi; Sun, Tao

2017-01-01

Unmanned Aerial Vehicles (UAVs) play an important role in applications such as data collection and target reconnaissance. An accurate and optimal path can effectively increase the mission success rate in the case of small UAVs. Although path planning for UAVs is similar to that for traditional mobile robots, the special kinematic characteristics of UAVs (such as their minimum turning radius) have not been taken into account in previous studies. In this paper, we propose a locally-adjustable, continuous-curvature, bounded path-planning algorithm for fixed-wing UAVs. To deal with the curvature discontinuity problem, an optimal interpolation algorithm and a key-point shift algorithm are proposed based on the derivation of a curvature continuity condition. To meet the upper bound for curvature and to render the curvature extrema controllable, a local replanning scheme is designed by combining arcs and Bezier curves with monotonic curvature. In particular, a path transition mechanism is built for the replanning phase using minimum curvature circles for a planning philosophy. Numerical results demonstrate that the analytical planning algorithm can effectively generate continuous-curvature paths, while satisfying the curvature upper bound constraint and allowing UAVs to pass through all predefined waypoints in the desired mission region. PMID:28925960

Paramagnetic or diamagnetic persistent currents? A topological point of view

NASA Astrophysics Data System (ADS)

Waintal, Xavier

2009-03-01

A persistent current flows at low temperatures in small conducting rings when they are threaded by a magnetic flux. I will discuss the sign of this persistent current (diamagnetic or paramagnetic response) in the special case of N electrons in a one dimensional ring [1]. One dimension is very special in the sense that the sign of the persistent current is entirely controlled by the topology of the system. I will establish lower bounds for the free energy in the presence of arbitrary electron-electron interactions and external potentials. Those bounds are the counterparts of upper bounds derived by Leggett using another topological argument. Rings with odd (even) numbers of polarized electrons are always diamagnetic (paramagnetic). The situation is more interesting with unpolarized electrons where Leggett upper bound breaks down: rings with N=4n exhibit either paramagnetic behavior or a superconductor-like current-phase relation. The topological argument provides a rigorous justification for the phenomenological Huckel rule which states that cyclic molecules with 4n + 2 electrons like benzene are aromatic while those with 4n electrons are not. [4pt] [1] Xavier Waintal, Geneviève Fleury, Kyryl Kazymyrenko, Manuel Houzet, Peter Schmitteckert, and Dietmar Weinmann Phys. Rev. Lett.101, 106804 (2008).

Curvature Continuous and Bounded Path Planning for Fixed-Wing UAVs.

PubMed

Wang, Xiaoliang; Jiang, Peng; Li, Deshi; Sun, Tao

2017-09-19

Unmanned Aerial Vehicles (UAVs) play an important role in applications such as data collection and target reconnaissance. An accurate and optimal path can effectively increase the mission success rate in the case of small UAVs. Although path planning for UAVs is similar to that for traditional mobile robots, the special kinematic characteristics of UAVs (such as their minimum turning radius) have not been taken into account in previous studies. In this paper, we propose a locally-adjustable, continuous-curvature, bounded path-planning algorithm for fixed-wing UAVs. To deal with the curvature discontinuity problem, an optimal interpolation algorithm and a key-point shift algorithm are proposed based on the derivation of a curvature continuity condition. To meet the upper bound for curvature and to render the curvature extrema controllable, a local replanning scheme is designed by combining arcs and Bezier curves with monotonic curvature. In particular, a path transition mechanism is built for the replanning phase using minimum curvature circles for a planning philosophy. Numerical results demonstrate that the analytical planning algorithm can effectively generate continuous-curvature paths, while satisfying the curvature upper bound constraint and allowing UAVs to pass through all predefined waypoints in the desired mission region.

The accuracy of less: Natural bounds explain why quantity decreases are estimated more accurately than quantity increases.

PubMed

Chandon, Pierre; Ordabayeva, Nailya

2017-02-01

Five studies show that people, including experts such as professional chefs, estimate quantity decreases more accurately than quantity increases. We argue that this asymmetry occurs because physical quantities cannot be negative. Consequently, there is a natural lower bound (zero) when estimating decreasing quantities but no upper bound when estimating increasing quantities, which can theoretically grow to infinity. As a result, the "accuracy of less" disappears (a) when a numerical or a natural upper bound is present when estimating quantity increases, or (b) when people are asked to estimate the (unbounded) ratio of change from 1 size to another for both increasing and decreasing quantities. Ruling out explanations related to loss aversion, symbolic number mapping, and the visual arrangement of the stimuli, we show that the "accuracy of less" influences choice and demonstrate its robustness in a meta-analysis that includes previously published results. Finally, we discuss how the "accuracy of less" may explain asymmetric reactions to the supersizing and downsizing of food portions, some instances of the endowment effect, and asymmetries in the perception of increases and decreases in physical and psychological distance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Bounds on area and charge for marginally trapped surfaces with a cosmological constant

NASA Astrophysics Data System (ADS)

Simon, Walter

2012-03-01

We sharpen the known inequalities AΛ ⩽ 4π(1 - g) (Hayward et al 1994 Phys. Rev. D 49 5080, Woolgar 1999 Class. Quantum Grav. 16 3005) and A ⩾ 4πQ2 (Dain et al 2012 Class. Quantum Grav. 29 035013) between the area A and the electric charge Q of a stable marginally outer-trapped surface (MOTS) of genus g in the presence of a cosmological constant Λ. In particular, instead of requiring stability we include the principal eigenvalue λ of the stability operator. For Λ* = Λ + λ > 0, we obtain a lower and an upper bound for Λ*A in terms of Λ*Q2, as well as the upper bound Q \\le 1/(2\\sqrt{\\Lambda ^{*}}) for the charge, which reduces to Q \\le 1/(2\\sqrt{\\Lambda }) in the stable case λ ⩾ 0. For Λ* < 0, there only remains a lower bound on A. In the spherically symmetric, static, stable case, one of our area inequalities is saturated iff the surface gravity vanishes. We also discuss implications of our inequalities for ‘jumps’ and mergers of charged MOTS.

Perturbative unitarity constraints on the NMSSM Higgs Sector

DOE PAGES

Betre, Kassahun; El Hedri, Sonia; Walker, Devin G. E.

2017-11-11

We place perturbative unitarity constraints on both the dimensionful and dimensionless parameters in the Next-to-Minimal Supersymmetric Standard Model (NMSSM) Higgs Sector. These constraints, plus the requirement that the singlino and/or Higgsino constitutes at least part of the observed dark matter relic abundance, generate upper bounds on the Higgs, neutralino and chargino mass spectrum. Requiring higher-order corrections to be no more than 41% of the tree-level value, we obtain an upper bound of 20 TeV for the heavy Higgses and 12 TeV for the charginos and neutralinos outside defined fine-tuned regions. If the corrections are no more than 20% of themore » tree-level value, the bounds are 7 TeV for the heavy Higgses and 5 TeV for the charginos and neutralinos. Finally, in all, by using the NMSSM as a template, we describe a method which replaces naturalness arguments with more rigorous perturbative unitarity arguments to get a better understanding of when new physics will appear.« less

An upper bound on the radius of a highly electrically conducting lunar core

NASA Technical Reports Server (NTRS)

Hobbs, B. A.; Hood, L. L.; Herbert, F.; Sonett, C. P.

1983-01-01

Parker's (1980) nonlinear inverse theory for the electromagnetic sounding problem is converted to a form suitable for analysis of lunar day-side transfer function data by: (1) transforming the solution in plane geometry to that in spherical geometry; and (2) transforming the theoretical lunar transfer function in the dipole limit to an apparent resistivity function. The theory is applied to the revised lunar transfer function data set of Hood et al. (1982), which extends in frequency from 10 to the -5th to 10 to the -3rd Hz. On the assumption that an iron-rich lunar core, whether molten or solid, can be represented by a perfect conductor at the minimum sampled frequency, an upper bound of 435 km on the maximum radius of such a core is calculated. This bound is somewhat larger than values of 360-375 km previously estimated from the same data set via forward model calculations because the prior work did not consider all possible mantle conductivity functions.

An upper bound on the particle-laden dependency of shear stresses at solid-fluid interfaces

NASA Astrophysics Data System (ADS)

Zohdi, T. I.

2018-03-01

In modern advanced manufacturing processes, such as three-dimensional printing of electronics, fine-scale particles are added to a base fluid yielding a modified fluid. For example, in three-dimensional printing, particle-functionalized inks are created by adding particles to freely flowing solvents forming a mixture, which is then deposited onto a surface, which upon curing yields desirable solid properties, such as thermal conductivity, electrical permittivity and magnetic permeability. However, wear at solid-fluid interfaces within the machinery walls that deliver such particle-laden fluids is typically attributed to the fluid-induced shear stresses, which increase with the volume fraction of added particles. The objective of this work is to develop a rigorous strict upper bound for the tolerable volume fraction of particles that can be added, while remaining below a given stress threshold at a fluid-solid interface. To illustrate the bound's utility, the expression is applied to a series of classical flow regimes.

Perturbative unitarity constraints on the NMSSM Higgs Sector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Betre, Kassahun; El Hedri, Sonia; Walker, Devin G. E.

We place perturbative unitarity constraints on both the dimensionful and dimensionless parameters in the Next-to-Minimal Supersymmetric Standard Model (NMSSM) Higgs Sector. These constraints, plus the requirement that the singlino and/or Higgsino constitutes at least part of the observed dark matter relic abundance, generate upper bounds on the Higgs, neutralino and chargino mass spectrum. Requiring higher-order corrections to be no more than 41% of the tree-level value, we obtain an upper bound of 20 TeV for the heavy Higgses and 12 TeV for the charginos and neutralinos outside defined fine-tuned regions. If the corrections are no more than 20% of themore » tree-level value, the bounds are 7 TeV for the heavy Higgses and 5 TeV for the charginos and neutralinos. Finally, in all, by using the NMSSM as a template, we describe a method which replaces naturalness arguments with more rigorous perturbative unitarity arguments to get a better understanding of when new physics will appear.« less

Quantum Dynamical Applications of Salem's Theorem

NASA Astrophysics Data System (ADS)

Damanik, David; Del Rio, Rafael

2009-07-01

We consider the survival probability of a state that evolves according to the Schrödinger dynamics generated by a self-adjoint operator H. We deduce from a classical result of Salem that upper bounds for the Hausdorff dimension of a set supporting the spectral measure associated with the initial state imply lower bounds on a subsequence of time scales for the survival probability. This general phenomenon is illustrated with applications to the Fibonacci operator and the critical almost Mathieu operator. In particular, this gives the first quantitative dynamical bound for the critical almost Mathieu operator.

Volumes and intrinsic diameters of hypersurfaces

NASA Astrophysics Data System (ADS)

Paeng, Seong-Hun

2015-09-01

We estimate the volume and the intrinsic diameter of a hypersurface M with geometric information of a hypersurface which is parallel to M at distance T. It can be applied to the Riemannian Penrose inequality to obtain a lower bound of the total mass of a spacetime. Also it can be used to obtain upper bounds of the volume and the intrinsic diameter of the celestial r-sphere without a lower bound of the sectional curvature. We extend our results to metric-measure spaces by using the Bakry-Emery Ricci tensor.

The SURE reliability analysis program

NASA Technical Reports Server (NTRS)

Butler, R. W.

1986-01-01

The SURE program is a new reliability tool for ultrareliable computer system architectures. The program is based on computational methods recently developed for the NASA Langley Research Center. These methods provide an efficient means for computing accurate upper and lower bounds for the death state probabilities of a large class of semi-Markov models. Once a semi-Markov model is described using a simple input language, the SURE program automatically computes the upper and lower bounds on the probability of system failure. A parameter of the model can be specified as a variable over a range of values directing the SURE program to perform a sensitivity analysis automatically. This feature, along with the speed of the program, makes it especially useful as a design tool.

The SURE Reliability Analysis Program

NASA Technical Reports Server (NTRS)

Butler, R. W.

1986-01-01

The SURE program is a new reliability analysis tool for ultrareliable computer system architectures. The program is based on computational methods recently developed for the NASA Langley Research Center. These methods provide an efficient means for computing accurate upper and lower bounds for the death state probabilities of a large class of semi-Markov models. Once a semi-Markov model is described using a simple input language, the SURE program automatically computes the upper and lower bounds on the probability of system failure. A parameter of the model can be specified as a variable over a range of values directing the SURE program to perform a sensitivity analysis automatically. This feature, along with the speed of the program, makes it especially useful as a design tool.

Quantum State Tomography via Linear Regression Estimation

PubMed Central

Qi, Bo; Hou, Zhibo; Li, Li; Dong, Daoyi; Xiang, Guoyong; Guo, Guangcan

2013-01-01

A simple yet efficient state reconstruction algorithm of linear regression estimation (LRE) is presented for quantum state tomography. In this method, quantum state reconstruction is converted into a parameter estimation problem of a linear regression model and the least-squares method is employed to estimate the unknown parameters. An asymptotic mean squared error (MSE) upper bound for all possible states to be estimated is given analytically, which depends explicitly upon the involved measurement bases. This analytical MSE upper bound can guide one to choose optimal measurement sets. The computational complexity of LRE is O(d4) where d is the dimension of the quantum state. Numerical examples show that LRE is much faster than maximum-likelihood estimation for quantum state tomography. PMID:24336519

The digital computer as a metaphor for the perfect laboratory experiment: Loophole-free Bell experiments

NASA Astrophysics Data System (ADS)

De Raedt, Hans; Michielsen, Kristel; Hess, Karl

2016-12-01

Using Einstein-Podolsky-Rosen-Bohm experiments as an example, we demonstrate that the combination of a digital computer and algorithms, as a metaphor for a perfect laboratory experiment, provides solutions to problems of the foundations of physics. Employing discrete-event simulation, we present a counterexample to John Bell's remarkable "proof" that any theory of physics, which is both Einstein-local and "realistic" (counterfactually definite), results in a strong upper bound to the correlations that are being measured in Einstein-Podolsky-Rosen-Bohm experiments. Our counterexample, which is free of the so-called detection-, coincidence-, memory-, and contextuality loophole, violates this upper bound and fully agrees with the predictions of quantum theory for Einstein-Podolsky-Rosen-Bohm experiments.

Event-based recursive filtering for a class of nonlinear stochastic parameter systems over fading channels

NASA Astrophysics Data System (ADS)

Shen, Yuxuan; Wang, Zidong; Shen, Bo; Alsaadi, Fuad E.

2018-07-01

In this paper, the recursive filtering problem is studied for a class of time-varying nonlinear systems with stochastic parameter matrices. The measurement transmission between the sensor and the filter is conducted through a fading channel characterized by the Rice fading model. An event-based transmission mechanism is adopted to decide whether the sensor measurement should be transmitted to the filter. A recursive filter is designed such that, in the simultaneous presence of the stochastic parameter matrices and fading channels, the filtering error covariance is guaranteed to have an upper bound and such an upper bound is then minimized by appropriately choosing filter gain matrix. Finally, a simulation example is presented to demonstrate the effectiveness of the proposed filtering scheme.

Combinatorial complexity of pathway analysis in metabolic networks.

PubMed

Klamt, Steffen; Stelling, Jörg

2002-01-01

Elementary flux mode analysis is a promising approach for a pathway-oriented perspective of metabolic networks. However, in larger networks it is hampered by the combinatorial explosion of possible routes. In this work we give some estimations on the combinatorial complexity including theoretical upper bounds for the number of elementary flux modes in a network of a given size. In a case study, we computed the elementary modes in the central metabolism of Escherichia coli while utilizing four different substrates. Interestingly, although the number of modes occurring in this complex network can exceed half a million, it is still far below the upper bound. Hence, to a certain extent, pathway analysis of central catabolism is feasible to assess network properties such as flexibility and functionality.

A one-dimensional model of solid-earth electrical resistivity beneath Florida

USGS Publications Warehouse

Blum, Cletus; Love, Jeffrey J.; Pedrie, Kolby; Bedrosian, Paul A.; Rigler, E. Joshua

2015-11-19

An estimated one-dimensional layered model of electrical resistivity beneath Florida was developed from published geological and geophysical information. The resistivity of each layer is represented by plausible upper and lower bounds as well as a geometric mean resistivity. Corresponding impedance transfer functions, Schmucker-Weidelt transfer functions, apparent resistivity, and phase responses are calculated for inducing geomagnetic frequencies ranging from 10−5 to 100 hertz. The resulting one-dimensional model and response functions can be used to make general estimates of time-varying electric fields associated with geomagnetic storms such as might represent induction hazards for electric-power grid operation. The plausible upper- and lower-bound resistivity structures show the uncertainty, giving a wide range of plausible time-varying electric fields.

Rebuttal to "On the distribution of the modulus of Gabor wavelet coefficients and the upper bound of the dimensionless smoothness index in the case of additive Gaussian noises: Revisited" by Dong Wang, Qiang Zhou, and Kwok-Leung Tsui

NASA Astrophysics Data System (ADS)

Soltani Bozchalooi, Iman; Liang, Ming

2018-04-01

A discussion paper entitled "On the distribution of the modulus of Gabor wavelet coefficients and the upper bound of the dimensionless smoothness index in the case of additive Gaussian noises: revisited" by Dong Wang, Qiang Zhou, Kwok-Leung Tsui has been brought to our attention recently. This discussion paper (hereafter called Wang et al. paper) is based on arguments that are fundamentally incorrect and which we rebut within this commentary. However, as the flaws in the arguments proposed by Wang et al. are clear, we will keep this rebuttal as brief as possible.

Two Upper Bounds for the Weighted Path Length of Binary Trees. Report No. UIUCDCS-R-73-565.

ERIC Educational Resources Information Center

Pradels, Jean Louis

Rooted binary trees with weighted nodes are structures encountered in many areas, such as coding theory, searching and sorting, information storage and retrieval. The path length is a meaningful quantity which gives indications about the expected time of a search or the length of a code, for example. In this paper, two sharp bounds for the total…

The Mystery of Io's Warm Polar Regions: Implications for Heat Flow

NASA Technical Reports Server (NTRS)

Matson, D. L.; Veeder, G. J.; Johnson, T. V.; Blaney, D. L.; Davies, A. G.

2002-01-01

Unexpectedly warm polar temperatures further support the idea that Io is covered virtually everywhere by cooling lava flows. This implies a new heat flow component. Io's heat flow remains constrained between a lower bound of (approximately) 2.5 W m(exp -2) and an upper bound of (approximately) 13 W m(exp -2). Additional information is contained in the original extended abstract.

Risk aversion and risk seeking in multicriteria forest management: a Markov decision process approach

Treesearch

Joseph Buongiorno; Mo Zhou; Craig Johnston

2017-01-01

Markov decision process models were extended to reflect some consequences of the risk attitude of forestry decision makers. One approach consisted of maximizing the expected value of a criterion subject to an upper bound on the variance or, symmetrically, minimizing the variance subject to a lower bound on the expected value.  The other method used the certainty...

Verifying the error bound of numerical computation implemented in computer systems

DOEpatents

Sawada, Jun

2013-03-12

A verification tool receives a finite precision definition for an approximation of an infinite precision numerical function implemented in a processor in the form of a polynomial of bounded functions. The verification tool receives a domain for verifying outputs of segments associated with the infinite precision numerical function. The verification tool splits the domain into at least two segments, wherein each segment is non-overlapping with any other segment and converts, for each segment, a polynomial of bounded functions for the segment to a simplified formula comprising a polynomial, an inequality, and a constant for a selected segment. The verification tool calculates upper bounds of the polynomial for the at least two segments, beginning with the selected segment and reports the segments that violate a bounding condition.

Gravitational wave emission from oscillating millisecond pulsars

NASA Astrophysics Data System (ADS)

Alford, Mark G.; Schwenzer, Kai

2015-02-01

Neutron stars undergoing r-mode oscillation emit gravitational radiation that might be detected on the Earth. For known millisecond pulsars the observed spin-down rate imposes an upper limit on the possible gravitational wave signal of these sources. Taking into account the physics of r-mode evolution, we show that only sources spinning at frequencies above a few hundred Hertz can be unstable to r-modes, and we derive a more stringent universal r-mode spin-down limit on their gravitational wave signal. We find that this refined bound limits the gravitational wave strain from millisecond pulsars to values below the detection sensitivity of next generation detectors. Young sources are therefore a more promising option for the detection of gravitational waves emitted by r-modes and to probe the interior composition of compact stars in the near future.

The cosmological Higgstory of the vacuum instability

DOE PAGES

Espinosa, José R.; Giudice, Gian F.; Morgante, Enrico; ...

2015-09-24

We report that the Standard Model Higgs potential becomes unstable at large field values. After clarifying the issue of gauge dependence of the effective potential, we study the cosmological evolution of the Higgs field in presence of this instability throughout inflation, reheating and the present epoch. We conclude that anti-de Sitter patches in which the Higgs field lies at its true vacuum are lethal for our universe. From this result, we derive upper bounds on the Hubble constant during inflation, which depend on the reheating temperature and on the Higgs coupling to the scalar curvature or to the inflaton. Finallymore » we study how a speculative link between Higgs meta-stability and consistence of quantum gravity leads to a sharp prediction for the Higgs and top masses, which is consistent with measured values.« less

Search for invisible decays of a Higgs boson using vector-boson fusion in pp collisions at √s = 8 TeV with the ATLAS detector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aad, G.; Abbott, B.; Abdallah, J.

2016-01-28

A search for a Higgs boson produced via vector-boson fusion and decaying into invisible particles is presented, using 20.3 fb -1 of proton-proton collision data at a centre-of-mass energy of 8 TeV recorded by the ATLAS detector at the LHC. For a Higgs boson with a mass of 125 GeV, assuming the Standard Model production cross section, an upper bound of 0.28 is set on the branching fraction of H → invisible at 95% confidence level, where the expected upper limit is 0.31. Furthermore, the results are interpreted in models of Higgs-portal dark matter where the branching fraction limit ismore » converted into upper bounds on the dark-matter-nucleon scattering cross section as a function of the dark-matter particle mass, and compared to results from the direct dark-matter detection experiments.« less

Statistical thermodynamics foundation for photovoltaic and photothermal conversion. II. Application to photovoltaic conversion

NASA Astrophysics Data System (ADS)

Badescu, Viorel; Landsberg, Peter T.

1995-08-01

The general theory developed in part I was applied to build up two models of photovoltaic conversion. To this end two different systems were analyzed. The first system consists of the whole absorber (converter), for which the balance equations for energy and entropy are written and then used to derive an upper bound for solar energy conversion. The second system covers a part of the absorber (converter), namely the valence and conduction electronic bands. The balance of energy is used in this case to derive, under additional assumptions, another upper limit for the conversion efficiency. This second system deals with the real location where the power is generated. Both models take into consideration the radiation polarization and reflection, and the effects of concentration. The second model yields a more accurate upper bound for the conversion efficiency. A generalized solar cell equation is derived. It is proved that other previous theories are particular cases of the present more general formalism.

Limits on the fluctuating part of y-type distortion monopole from Planck and SPT results

NASA Astrophysics Data System (ADS)

Khatri, Rishi; Sunyaev, Rashid

2015-08-01

We use the published Planck and SPT cluster catalogs [1,2] and recently published y-distortion maps [3] to put strong observational limits on the contribution of the fluctuating part of the y-type distortions to the y-distortion monopole. Our bounds are 5.4× 10-8 < langle yrangle < 2.2× 10-6. Our upper bound is a factor of 6.8 stronger than the currently best upper 95% confidence limit from COBE-FIRAS of langle yrangle <15× 10-6. In the standard cosmology, large scale structure is the only source of such distortions and our limits therefore constrain the baryonic physics involved in the formation of the large scale structure. Our lower limit, from the detected clusters in the Planck and SPT catalogs, also implies that a Pixie-like experiment should detect the y-distortion monopole at >27-σ. The biggest sources of uncertainty in our upper limit are the monopole offsets between different HFI channel maps that we estimate to be <10-6.

On the realization of the bulk modulus bounds for two-phase viscoelastic composites

NASA Astrophysics Data System (ADS)

Andreasen, Casper Schousboe; Andreassen, Erik; Jensen, Jakob Søndergaard; Sigmund, Ole

2014-02-01

Materials with good vibration damping properties and high stiffness are of great industrial interest. In this paper the bounds for viscoelastic composites are investigated and material microstructures that realize the upper bound are obtained by topology optimization. These viscoelastic composites can be realized by additive manufacturing technologies followed by an infiltration process. Viscoelastic composites consisting of a relatively stiff elastic phase, e.g. steel, and a relatively lossy viscoelastic phase, e.g. silicone rubber, have non-connected stiff regions when optimized for maximum damping. In order to ensure manufacturability of such composites the connectivity of the matrix is ensured by imposing a conductivity constraint and the influence on the bounds is discussed.

1-norm support vector novelty detection and its sparseness.

PubMed

Zhang, Li; Zhou, WeiDa

2013-12-01

This paper proposes a 1-norm support vector novelty detection (SVND) method and discusses its sparseness. 1-norm SVND is formulated as a linear programming problem and uses two techniques for inducing sparseness, or the 1-norm regularization and the hinge loss function. We also find two upper bounds on the sparseness of 1-norm SVND, or exact support vector (ESV) and kernel Gram matrix rank bounds. The ESV bound indicates that 1-norm SVND has a sparser representation model than SVND. The kernel Gram matrix rank bound can loosely estimate the sparseness of 1-norm SVND. Experimental results show that 1-norm SVND is feasible and effective. Copyright © 2013 Elsevier Ltd. All rights reserved.

On the perturbation of the group generalized inverse for a class of bounded operators in Banach spaces

NASA Astrophysics Data System (ADS)

Castro-González, N.; Vélez-Cerrada, J. Y.

2008-05-01

Given a bounded operator A on a Banach space X with Drazin inverse AD and index r, we study the class of group invertible bounded operators B such that I+AD(B-A) is invertible and . We show that they can be written with respect to the decomposition as a matrix operator, , where B1 and are invertible. Several characterizations of the perturbed operators are established, extending matrix results. We analyze the perturbation of the Drazin inverse and we provide explicit upper bounds of ||B#-AD|| and ||BB#-ADA||. We obtain a result on the continuity of the group inverse for operators on Banach spaces.

Bounds on invisible Higgs boson decays extracted from LHC ttH production data.

PubMed

Zhou, Ning; Khechadoorian, Zepyoor; Whiteson, Daniel; Tait, Tim M P

2014-10-10

We present an upper bound on the branching fraction of the Higgs boson to invisible particles by recasting a CMS Collaboration search for stop quarks decaying to tt + E(T)(miss). The observed (expected) bound, BF(H → inv.) < 0.40(0.65) at 95% C.L., is the strongest direct limit to date, benefiting from a downward fluctuation in the CMS data in that channel. In addition, we combine this new constraint with existing published constraints to give an observed (expected) bound of BF(H → inv.) < 0.40(0.40) at 95% C.L., and we show some of the implications for theories of dark matter which communicate through the Higgs portal.

Money Gone Up in Smoke: The Tobacco Use and Malnutrition Nexus in Bangladesh

PubMed Central

Husain, Muhammad Jami; Virk-Baker, Mandeep; Parascandola, Mark; Khondker, Bazlul Haque; Ahluwalia, Indu B.

2017-01-01

BACKGROUND The tobacco epidemic in Bangladesh is pervasive. Expenditures on tobacco may reduce money available for food in a country with a high malnutrition rate. OBJECTIVES The aims of the study are to quantify the opportunity costs of tobacco expenditure in terms of nutrition (ie, food energy) forgone and the potential improvements in the household level food-energy status if the money spent on tobacco were diverted for food consumption. METHOD We analyzed data from the 2010 Bangladesh Household Income and Expenditure Survey, a nationally representative survey conducted among 12,240 households. We present 2 analytical scenarios: (1) the lower-bound gain scenario entailing money spent on tobacco partially diverted to acquiring food according to households’ food consumption share in total expenditures; and (2) the upper-bound gain scenario entailing money spent on tobacco diverted to acquiring food only. Age- and gender-based energy norms were used to identify food-energy deficient households. Data were analyzed by mutually exclusive smoking-only, smokeless-only, and dual-tobacco user households. FINDINGS On average, a smoking-only household could gain 269–497 kilocalories (kcal) daily under the lower-bound and upper-bound scenarios, respectively. The potential energy gains for smokeless-only and dual-tobacco user households ranged from 148–268 kcal and 508–924 kcal, respectively. Under these lower- and upper-bound estimates, the percentage of smoking-only user households that are malnourished declined significantly from the baseline rate of 38% to 33% and 29%, respectively. For the smokeless-only and dual-tobacco user households, there were 2–3 and 6–9 percentage point drops in the malnutrition prevalence rates. The tobacco expenditure shift could translate to an additional 4.6–7.7 million food-energy malnourished persons meeting their caloric requirements. CONCLUSIONS The findings suggest that tobacco use reduction could facilitate concomitant improvements in population-level nutrition status and may inform the development and refinement of tobacco prevention and control efforts in Bangladesh. PMID:28283125

Money Gone Up in Smoke: The Tobacco Use and Malnutrition Nexus in Bangladesh.

PubMed

Husain, Muhammad Jami; Virk-Baker, Mandeep; Parascandola, Mark; Khondker, Bazlul Haque; Ahluwalia, Indu B

The tobacco epidemic in Bangladesh is pervasive. Expenditures on tobacco may reduce money available for food in a country with a high malnutrition rate. The aims of the study are to quantify the opportunity costs of tobacco expenditure in terms of nutrition (ie, food energy) forgone and the potential improvements in the household level food-energy status if the money spent on tobacco were diverted for food consumption. We analyzed data from the 2010 Bangladesh Household Income and Expenditure Survey, a nationally representative survey conducted among 12,240 households. We present 2 analytical scenarios: (1) the lower-bound gain scenario entailing money spent on tobacco partially diverted to acquiring food according to households' food consumption share in total expenditures; and (2) the upper-bound gain scenario entailing money spent on tobacco diverted to acquiring food only. Age- and gender-based energy norms were used to identify food-energy deficient households. Data were analyzed by mutually exclusive smoking-only, smokeless-only, and dual-tobacco user households. On average, a smoking-only household could gain 269-497 kilocalories (kcal) daily under the lower-bound and upper-bound scenarios, respectively. The potential energy gains for smokeless-only and dual-tobacco user households ranged from 148-268 kcal and 508-924 kcal, respectively. Under these lower- and upper-bound estimates, the percentage of smoking-only user households that are malnourished declined significantly from the baseline rate of 38% to 33% and 29%, respectively. For the smokeless-only and dual-tobacco user households, there were 2-3 and 6-9 percentage point drops in the malnutrition prevalence rates. The tobacco expenditure shift could translate to an additional 4.6-7.7 million food-energy malnourished persons meeting their caloric requirements. The findings suggest that tobacco use reduction could facilitate concomitant improvements in population-level nutrition status and may inform the development and refinement of tobacco prevention and control efforts in Bangladesh. Copyright © 2016. Published by Elsevier Inc.

Termination Proofs for String Rewriting Systems via Inverse Match-Bounds

NASA Technical Reports Server (NTRS)

Butler, Ricky (Technical Monitor); Geser, Alfons; Hofbauer, Dieter; Waldmann, Johannes

2004-01-01

Annotating a letter by a number, one can record information about its history during a reduction. A string rewriting system is called match-bounded if there is a global upper bound to these numbers. In earlier papers we established match-boundedness as a strong sufficient criterion for both termination and preservation of regular languages. We show now that the string rewriting system whose inverse (left and right hand sides exchanged) is match-bounded, also have exceptional properties, but slightly different ones. Inverse match-bounded systems effectively preserve context-free languages; their sets of normalized strings and their sets of immortal strings are effectively regular. These sets of strings can be used to decide the normalization, the termination and the uniform termination problems of inverse match-bounded systems. We also show that the termination problem is decidable in linear time, and that a certain strong reachability problem is deciable, thus solving two open problems of McNaughton's.

Bounded Linear Stability Analysis - A Time Delay Margin Estimation Approach for Adaptive Control

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.; Ishihara, Abraham K.; Krishnakumar, Kalmanje Srinlvas; Bakhtiari-Nejad, Maryam

2009-01-01

This paper presents a method for estimating time delay margin for model-reference adaptive control of systems with almost linear structured uncertainty. The bounded linear stability analysis method seeks to represent the conventional model-reference adaptive law by a locally bounded linear approximation within a small time window using the comparison lemma. The locally bounded linear approximation of the combined adaptive system is cast in a form of an input-time-delay differential equation over a small time window. The time delay margin of this system represents a local stability measure and is computed analytically by a matrix measure method, which provides a simple analytical technique for estimating an upper bound of time delay margin. Based on simulation results for a scalar model-reference adaptive control system, both the bounded linear stability method and the matrix measure method are seen to provide a reasonably accurate and yet not too conservative time delay margin estimation.

Tightening the entropic uncertainty bound in the presence of quantum memory

NASA Astrophysics Data System (ADS)

Adabi, F.; Salimi, S.; Haseli, S.

2016-06-01

The uncertainty principle is a fundamental principle in quantum physics. It implies that the measurement outcomes of two incompatible observables cannot be predicted simultaneously. In quantum information theory, this principle can be expressed in terms of entropic measures. M. Berta et al. [Nat. Phys. 6, 659 (2010), 10.1038/nphys1734] have indicated that uncertainty bound can be altered by considering a particle as a quantum memory correlating with the primary particle. In this article, we obtain a lower bound for entropic uncertainty in the presence of a quantum memory by adding an additional term depending on the Holevo quantity and mutual information. We conclude that our lower bound will be tightened with respect to that of Berta et al. when the accessible information about measurements outcomes is less than the mutual information about the joint state. Some examples have been investigated for which our lower bound is tighter than Berta et al.'s lower bound. Using our lower bound, a lower bound for the entanglement of formation of bipartite quantum states has been obtained, as well as an upper bound for the regularized distillable common randomness.

Safe Upper-Bounds Inference of Energy Consumption for Java Bytecode Applications

NASA Technical Reports Server (NTRS)

Navas, Jorge; Mendez-Lojo, Mario; Hermenegildo, Manuel V.

2008-01-01

Many space applications such as sensor networks, on-board satellite-based platforms, on-board vehicle monitoring systems, etc. handle large amounts of data and analysis of such data is often critical for the scientific mission. Transmitting such large amounts of data to the remote control station for analysis is usually too expensive for time-critical applications. Instead, modern space applications are increasingly relying on autonomous on-board data analysis. All these applications face many resource constraints. A key requirement is to minimize energy consumption. Several approaches have been developed for estimating the energy consumption of such applications (e.g. [3, 1]) based on measuring actual consumption at run-time for large sets of random inputs. However, this approach has the limitation that it is in general not possible to cover all possible inputs. Using formal techniques offers the potential for inferring safe energy consumption bounds, thus being specially interesting for space exploration and safety-critical systems. We have proposed and implemented a general frame- work for resource usage analysis of Java bytecode [2]. The user defines a set of resource(s) of interest to be tracked and some annotations that describe the cost of some elementary elements of the program for those resources. These values can be constants or, more generally, functions of the input data sizes. The analysis then statically derives an upper bound on the amount of those resources that the program as a whole will consume or provide, also as functions of the input data sizes. This article develops a novel application of the analysis of [2] to inferring safe upper bounds on the energy consumption of Java bytecode applications. We first use a resource model that describes the cost of each bytecode instruction in terms of the joules it consumes. With this resource model, we then generate energy consumption cost relations, which are then used to infer safe upper bounds. How energy consumption for each bytecode instruction is measured is beyond the scope of this paper. Instead, this paper is about how to infer safe energy consumption estimations assuming that those energy consumption costs are provided. For concreteness, we use a simplified version of an existing resource model [1] in which an energy consumption cost for individual Java opcodes is defined.

Universal bounds on the time evolution of entanglement entropy.

PubMed

Avery, Steven G; Paulos, Miguel F

2014-12-05

Using relative entropy, we derive bounds on the time rate of change of geometric entanglement entropy for any relativistic quantum field theory in any dimension. The bounds apply to both mixed and pure states, and may be extended to curved space. We illustrate the bounds in a few examples and comment on potential applications and future extensions.

Are culture-bound syndromes as real as universally-occurring disorders?

PubMed

Cooper, Rachel

2010-12-01

This paper asks what it means to say that a disorder is a "real" disorder and then considers whether culture-bound syndromes are real disorders. Following J.L. Austin I note that when we ask whether some supposed culture-bound syndrome is a real disorder we should start by specifying what possible alternatives we have in mind. We might be asking whether the reported behaviours genuinely occur, that is, whether the culture-bound syndrome is a genuine phenomenon as opposed to a myth. We might be wondering whether the condition should rightly be considered a disorder, as opposed to some sort of non-disorder condition (for example, a non-disorder form of deviance, or a potentially valuable condition). We might want to know whether the culture-bound syndrome is really a distinct disorder, in the sense that scientific classification systems should include it as a separate category, or whether it is just a variant of a universally occurring disorder. I argue that some specific difficulties can arise with determining whether a culture-bound syndrome is a real disorder in each of these three senses. However, the frequent assumption that real disorders will necessarily occur universally, and that those that occur only in certain environments are suspicious is not generally justified. Copyright © 2010 Elsevier Ltd. All rights reserved.

Hardening Effect Analysis by Modular Upper Bound and Finite Element Methods in Indentation of Aluminum, Steel, Titanium and Superalloys

PubMed Central

Bermudo, Carolina; Sevilla, Lorenzo; Martín, Francisco; Trujillo, Francisco Javier

2017-01-01

The application of incremental processes in the manufacturing industry is having a great development in recent years. The first stage of an Incremental Forming Process can be defined as an indentation. Because of this, the indentation process is starting to be widely studied, not only as a hardening test but also as a forming process. Thus, in this work, an analysis of the indentation process under the new Modular Upper Bound perspective has been performed. The modular implementation has several advantages, including the possibility of the introduction of different parameters to extend the study, such as the friction effect, the temperature or the hardening effect studied in this paper. The main objective of the present work is to analyze the three hardening models developed depending on the material characteristics. In order to support the validation of the hardening models, finite element analyses of diverse materials under an indentation are carried out. Results obtained from the Modular Upper Bound are in concordance with the results obtained from the numerical analyses. In addition, the numerical and analytical methods are in concordance with the results previously obtained in the experimental indentation of annealed aluminum A92030. Due to the introduction of the hardening factor, the new modular distribution is a suitable option for the analysis of indentation process. PMID:28772914

Exploring L1 model space in search of conductivity bounds for the MT problem

NASA Astrophysics Data System (ADS)

Wheelock, B. D.; Parker, R. L.

2013-12-01

Geophysical inverse problems of the type encountered in electromagnetic techniques are highly non-unique. As a result, any single inverted model, though feasible, is at best inconclusive and at worst misleading. In this paper, we use modified inversion methods to establish bounds on electrical conductivity within a model of the earth. Our method consists of two steps, each making use of the 1-norm in model regularization. Both 1-norm minimization problems are framed without approximation as non-negative least-squares (NNLS) problems. First, we must identify a parsimonious set of regions within the model for which upper and lower bounds on average conductivity will be sought. This is accomplished by minimizing the 1-norm of spatial variation, which produces a model with a limited number of homogeneous regions; in fact, the number of homogeneous regions will never be greater than the number of data, regardless of the number of free parameters supplied. The second step establishes bounds for each of these regions with pairs of inversions. The new suite of inversions also uses a 1-norm penalty, but applied to the conductivity values themselves, rather than the spatial variation thereof. In the bounding step we use the 1-norm of our model parameters because it is proportional to average conductivity. For a lower bound on average conductivity, the 1-norm within a bounding region is minimized. For an upper bound on average conductivity, the 1-norm everywhere outside a bounding region is minimized. The latter minimization has the effect of concentrating conductance into the bounding region. Taken together, these bounds are a measure of the uncertainty in the associated region of our model. Starting with a blocky inverse solution is key in the selection of the bounding regions. Of course, there is a tradeoff between resolution and uncertainty: an increase in resolution (smaller bounding regions), results in greater uncertainty (wider bounds). Minimization of the 1-norm of spatial variation delivers the fewest possible regions defined by a mean conductivity, the quantity we wish to bound. Thus, these regions present a natural set for which the most narrow and discriminating bounds can be found. For illustration, we apply these techniques to synthetic magnetotelluric (MT) data sets resulting from one-dimensional (1D) earth models. In each case we find that with realistic data coverage, any single inverted model can often stray from the truth, while the computed bounds on an encompassing region contain both the inverted and the true conductivities, indicating that our measure of model uncertainty is robust. Such estimates of uncertainty for conductivity can then be translated to bounds on important petrological parameters such as mineralogy, porosity, saturation, and fluid type.

Pharmacokinetics and repolarization effects of intravenous and transdermal granisetron.

PubMed

Mason, Jay W; Selness, Daniel S; Moon, Thomas E; O'Mahony, Bridget; Donachie, Peter; Howell, Julian

2012-05-15

The need for greater clarity about the effects of 5-HT(3) receptor antagonists on cardiac repolarization is apparent in the changing product labeling across this therapeutic class. This study assessed the repolarization effects of granisetron, a 5-HT(3) receptor antagonist antiemetic, administered intravenously and by a granisetron transdermal system (GTDS). In a parallel four-arm study, healthy subjects were randomized to receive intravenous granisetron, GTDS, placebo, or oral moxifloxacin (active control). The primary endpoint was difference in change from baseline in mean Fridericia-corrected QT interval (QTcF) between GTDS and placebo (ddQTcF) on days 3 and 5. A total of 240 subjects were enrolled, 60 in each group. Adequate sensitivity for detection of QTc change was shown by a 5.75 ms lower bound of the 90% confidence interval (CI) for moxifloxacin versus placebo at 2 hours postdose on day 3. Day 3 ddQTcF values varied between 0.2 and 1.9 ms for GTDS (maximum upper bound of 90% CI, 6.88 ms), between -1.2 and 1.6 ms for i.v. granisetron (maximum upper bound of 90% CI, 5.86 ms), and between -3.4 and 4.7 ms for moxifloxacin (maximum upper bound of 90% CI, 13.45 ms). Day 5 findings were similar. Pharmacokinetic-ddQTcF modeling showed a minimally positive slope of 0.157 ms/(ng/mL), but a very low correlation (r = 0.090). GTDS was not associated with statistically or clinically significant effects on QTcF or other electrocardiographic variables. This study provides useful clarification on the effect of granisetron delivered by GTDS on cardiac repolarization. ©2012 AACR.

Using a Water Balance Model to Bound Potential Irrigation Development in the Upper Blue Nile Basin

NASA Astrophysics Data System (ADS)

Jain Figueroa, A.; McLaughlin, D.

2016-12-01

The Grand Ethiopian Renaissance Dam (GERD), on the Blue Nile is an example of water resource management underpinning food, water and energy security. Downstream countries have long expressed concern about water projects in Ethiopia because of possible diversions to agricultural uses that could reduce flow in the Nile. Such diversions are attractive to Ethiopia as a partial solution to its food security problems but they could also conflict with hydropower revenue from GERD. This research estimates an upper bound on diversions above the GERD project by considering the potential for irrigated agriculture expansion and, in particular, the availability of water and land resources for crop production. Although many studies have aimed to simulate downstream flows for various Nile basin management plans, few have taken the perspective of bounding the likely impacts of upstream agricultural development. The approach is to construct an optimization model to establish a bound on Upper Blue Nile (UBN) agricultural development, paying particular attention to soil suitability and seasonal variability in climate. The results show that land and climate constraints impose significant limitations on crop production. Only 25% of the land area is suitable for irrigation due to the soil, slope and temperature constraints. When precipitation is also considered only 11% of current land area could be used in a way that increases water consumption. The results suggest that Ethiopia could consume an additional 3.75 billion cubic meters (bcm) of water per year, through changes in land use and storage capacity. By exploiting this irrigation potential, Ethiopia could potentially decrease the annual flow downstream of the UBN by 8 percent from the current 46 bcm/y to the modeled 42 bcm/y.

FACTORING TO FIT OFF DIAGONALS.

DTIC Science & Technology

imply an upper bound on the number of factors. When applied to somatotype data, the method improved substantially on centroid solutions and indicated a reinterpretation of earlier factoring studies. (Author)

Evolution of cosmic string networks

NASA Technical Reports Server (NTRS)

Albrecht, Andreas; Turok, Neil

1989-01-01

Results on cosmic strings are summarized including: (1) the application of non-equilibrium statistical mechanics to cosmic string evolution; (2) a simple one scale model for the long strings which has a great deal of predictive power; (3) results from large scale numerical simulations; and (4) a discussion of the observational consequences of our results. An upper bound on G mu of approximately 10(-7) emerges from the millisecond pulsar gravity wave bound. How numerical uncertainties affect this are discussed. Any changes which weaken the bound would probably also give the long strings the dominant role in producing observational consequences.

Approximating Multilinear Monomial Coefficients and Maximum Multilinear Monomials in Multivariate Polynomials

NASA Astrophysics Data System (ADS)

Chen, Zhixiang; Fu, Bin

This paper is our third step towards developing a theory of testing monomials in multivariate polynomials and concentrates on two problems: (1) How to compute the coefficients of multilinear monomials; and (2) how to find a maximum multilinear monomial when the input is a ΠΣΠ polynomial. We first prove that the first problem is #P-hard and then devise a O *(3 n s(n)) upper bound for this problem for any polynomial represented by an arithmetic circuit of size s(n). Later, this upper bound is improved to O *(2 n ) for ΠΣΠ polynomials. We then design fully polynomial-time randomized approximation schemes for this problem for ΠΣ polynomials. On the negative side, we prove that, even for ΠΣΠ polynomials with terms of degree ≤ 2, the first problem cannot be approximated at all for any approximation factor ≥ 1, nor "weakly approximated" in a much relaxed setting, unless P=NP. For the second problem, we first give a polynomial time λ-approximation algorithm for ΠΣΠ polynomials with terms of degrees no more a constant λ ≥ 2. On the inapproximability side, we give a n (1 - ɛ)/2 lower bound, for any ɛ> 0, on the approximation factor for ΠΣΠ polynomials. When the degrees of the terms in these polynomials are constrained as ≤ 2, we prove a 1.0476 lower bound, assuming Pnot=NP; and a higher 1.0604 lower bound, assuming the Unique Games Conjecture.

Necessary and sufficient criterion for extremal quantum correlations in the simplest Bell scenario

NASA Astrophysics Data System (ADS)

Ishizaka, Satoshi

2018-05-01

In the study of quantum nonlocality, one obstacle is that the analytical criterion for identifying the boundaries between quantum and postquantum correlations has not yet been given, even in the simplest Bell scenario. We propose a plausible, analytical, necessary and sufficient condition ensuring that a nonlocal quantum correlation in the simplest scenario is an extremal boundary point. Our extremality condition amounts to certifying an information-theoretical quantity; the probability of guessing a measurement outcome of a distant party optimized using any quantum instrument. We show that this quantity can be upper and lower bounded from any correlation in a device-independent way, and we use numerical calculations to confirm that coincidence of the upper and lower bounds appears to be necessary and sufficient for the extremality.

On the validity of the Arrhenius equation for electron attachment rate coefficients.

PubMed

Fabrikant, Ilya I; Hotop, Hartmut

2008-03-28

The validity of the Arrhenius equation for dissociative electron attachment rate coefficients is investigated. A general analysis allows us to obtain estimates of the upper temperature bound for the range of validity of the Arrhenius equation in the endothermic case and both lower and upper bounds in the exothermic case with a reaction barrier. The results of the general discussion are illustrated by numerical examples whereby the rate coefficient, as a function of temperature for dissociative electron attachment, is calculated using the resonance R-matrix theory. In the endothermic case, the activation energy in the Arrhenius equation is close to the threshold energy, whereas in the case of exothermic reactions with an intermediate barrier, the activation energy is found to be substantially lower than the barrier height.

On dynamic tumor eradication conditions under combined chemical/anti-angiogenic therapies

NASA Astrophysics Data System (ADS)

Starkov, Konstantin E.

2018-02-01

In this paper ultimate dynamics of the five-dimensional cancer tumor growth model at the angiogenesis phase is studied. This model elaborated by Pinho et al. in 2014 describes interactions between normal/cancer/endothelial cells under chemotherapy/anti-angiogenic agents in tumor growth process. The author derives ultimate upper bounds for normal/tumor/endothelial cells concentrations and ultimate upper and lower bounds for chemical/anti-angiogenic concentrations. Global asymptotic tumor clearance conditions are obtained for two versions: the use of only chemotherapy and the combined application of chemotherapy and anti-angiogenic therapy. These conditions are established as the attraction conditions to the maximum invariant set in the tumor free plane, and furthermore, the case is examined when this set consists only of tumor free equilibrium points.

Robust guaranteed cost tracking control of quadrotor UAV with uncertainties.

PubMed

Xu, Zhiwei; Nian, Xiaohong; Wang, Haibo; Chen, Yinsheng

2017-07-01

In this paper, a robust guaranteed cost controller (RGCC) is proposed for quadrotor UAV system with uncertainties to address set-point tracking problem. A sufficient condition of the existence for RGCC is derived by Lyapunov stability theorem. The designed RGCC not only guarantees the whole closed-loop system asymptotically stable but also makes the quadratic performance level built for the closed-loop system have an upper bound irrespective to all admissible parameter uncertainties. Then, an optimal robust guaranteed cost controller is developed to minimize the upper bound of performance level. Simulation results verify the presented control algorithms possess small overshoot and short setting time, with which the quadrotor has ability to perform set-point tracking task well. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Thermal dark matter co-annihilating with a strongly interacting scalar

NASA Astrophysics Data System (ADS)

Biondini, S.; Laine, M.

2018-04-01

Recently many investigations have considered Majorana dark matter co-annihilating with bound states formed by a strongly interacting scalar field. However only the gluon radiation contribution to bound state formation and dissociation, which at high temperatures is subleading to soft 2 → 2 scatterings, has been included. Making use of a non-relativistic effective theory framework and solving a plasma-modified Schrödinger equation, we address the effect of soft 2 → 2 scatterings as well as the thermal dissociation of bound states. We argue that the mass splitting between the Majorana and scalar field has in general both a lower and an upper bound, and that the dark matter mass scale can be pushed at least up to 5…6TeV.

A Priori Bound on the Velocity in Axially Symmetric Navier-Stokes Equations

NASA Astrophysics Data System (ADS)

Lei, Zhen; Navas, Esteban A.; Zhang, Qi S.

2016-01-01

Let v be the velocity of Leray-Hopf solutions to the axially symmetric three-dimensional Navier-Stokes equations. Under suitable conditions for initial values, we prove the following a priori bound |v(x, t)| ≤ C |ln r|^{1/2}/r^2, qquad 0 < r ≤ 1/2, where r is the distance from x to the z axis, and C is a constant depending only on the initial value. This provides a pointwise upper bound (worst case scenario) for possible singularities, while the recent papers (Chiun-Chuan et al., Commun PDE 34(1-3):203-232, 2009; Koch et al., Acta Math 203(1):83-105, 2009) gave a lower bound. The gap is polynomial order 1 modulo a half log term.

Viscosity bound versus the universal relaxation bound

NASA Astrophysics Data System (ADS)

Hod, Shahar

2017-10-01

For gauge theories with an Einstein gravity dual, the AdS/CFT correspondence predicts a universal value for the ratio of the shear viscosity to the entropy density, η / s = 1 / 4 π. The holographic calculations have motivated the formulation of the celebrated KSS conjecture, according to which all fluids conform to the lower bound η / s ≥ 1 / 4 π. The bound on η / s may be regarded as a lower bound on the relaxation properties of perturbed fluids and it has been the focus of much recent attention. In particular, it was argued that for a class of field theories with Gauss-Bonnet gravity dual, the shear viscosity to entropy density ratio, η / s, could violate the conjectured KSS bound. In the present paper we argue that the proposed violations of the KSS bound are strongly constrained by Bekenstein's generalized second law (GSL) of thermodynamics. In particular, it is shown that physical consistency of the Gauss-Bonnet theory with the GSL requires its coupling constant to be bounded by λGB ≲ 0 . 063. We further argue that the genuine physical bound on the relaxation properties of physically consistent fluids is ℑω(k > 2 πT) > πT, where ω and k are respectively the proper frequency and the wavenumber of a perturbation mode in the fluid.

Observational constraints on quantum decoherence during inflation

NASA Astrophysics Data System (ADS)

Martin, Jérôme; Vennin, Vincent

2018-05-01

Since inflationary perturbations must generically couple to all degrees of freedom present in the early Universe, it is more realistic to view these fluctuations as an open quantum system interacting with an environment. Then, on very general grounds, their evolution can be modelled with a Lindblad equation. This modified evolution leads to quantum decoherence of the system, as well as to corrections to observables such as the power spectrum of curvature fluctuations. On one hand, current cosmological observations constrain the properties of possible environments and place upper bounds on the interaction strengths. On the other hand, imposing that decoherence completes by the end of inflation implies lower bounds on the interaction strengths. Therefore, the question arises of whether successful decoherence can occur without altering the power spectrum. In this paper, we systematically identify all scenarios in which this is possible. As an illustration, we discuss the case in which the environment consists of a heavy test scalar field. We show that this realises the very peculiar configuration where the correction to the power spectrum is quasi scale invariant. In that case, the presence of the environment improves the fit to the data for some inflationary models but deteriorates it for others. This clearly demonstrates that decoherence is not only of theoretical importance but can also be crucial for astrophysical observations.

Determination of 3D surface displacement rates in the Upper Rhine Graben based on GURN (GNSS Upper Rhine Graben Network)

NASA Astrophysics Data System (ADS)

Mayer, M.; Knöpfler, A.; Masson, F.; Ulrich, P.; Heck, B.

2012-04-01

In September 2008, the Institut de Physique du Globe de Strasbourg (Ecole et Observatoire des Sciences de la Terre) and the Geodetic Institute of Karlsruhe University (now: Karlsruhe Institute of Technology) established the transnational cooperation GURN (GNSS Upper Rhine Graben Network). Within the GURN initiative, these institutions are cooperating in order to carry out geo-scientific research in the framework of the transnational project TOPO-WECEP (Western and Central European Platform; link: http://www.topo-wecep.eu/), which succeeded the former project URGENT (Upper Rhine Graben Evolution and NeoTectonics; link: http://comp1.geol.unibas.ch) of the EUCOR universities (European Confederation of Upper Rhine Universities). The Rhine Graben is the central segment of the European Cenozoic rift system, which extends from the North Sea through Germany and France to the Mediterranean coast over a distance of some 1100 km. GURN focusses on the Upper Rhine Graben (URG). The URG is a 300 km long and 40 km wide SSW-NNE trending rift, extending from Basel (Switzerland) to Frankfurt (Germany). It is limited to the west by the Vosges Mountains and to the east by the Black Forest Mountains, culminating in elevations of approx. 1500 m. The uplifted area of the Rhenish Massif bounds the URG to the north. To the south, the Leymen, Ferrette, and Vendlincourt folds represent the northernmost structural front of the Jura fold and thrust belt. Present-day distribution of the seismicity in the URG area is classified as moderate but not null. Expected velocities and strain rates are very low (relative velocities lower than 0.1mm/yr). The research is actually based on data of GNSS (Global Navigation Satellite Systems). A highly precise and highly sensitive geodetic network of permanently operating GNSS sites region has been established in the URG region in order to detect recent short-term (data base starting in year 2002) crustal movements based on displacements of GNSS sites. The regional network GURN actually consists of approx. 80 permanently operating GNSS sites of different data providers in Germany, France and Switzerland. The first work steps in the context of GURN were dominated by a detailed analysis of the GNSS data base (e.g., instrumental change artefacts). This analysis included a comparison of the working group related results (EOST, GIK), where different software packages and data handling strategies were used to derive 3D coordinate time series as basis for the determination of a 3D surface displacement field. Due to very small expected velocities in the URG region, the recent GURN focus is on the reliable derivation of site velocities, therefore effects of datum realisation have to be handled with care. The presentation gives an insight into the joint venture GURN focussing on recent results (e.g., 3D surface velocity field).

University of Florida Campus, Plaza of the Americas, University of ...

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

University of Florida Campus, Plaza of the Americas, University of Florida Campus Quad Bounded by West University Avenue, US 441/Southwest 13th Street, Stadium Road, and North-South Drive, Gainesville, Alachua County, FL

Detection of Pneumonia Associated Pathogens Using a Prototype Multiplexed Pneumonia Test in Hospitalized Patients with Severe Pneumonia

PubMed Central

Schulte, Berit; Eickmeyer, Holm; Heininger, Alexandra; Juretzek, Stephanie; Karrasch, Matthias; Denis, Olivier; Roisin, Sandrine; Pletz, Mathias W.; Klein, Matthias; Barth, Sandra; Lüdke, Gerd H.; Thews, Anne; Torres, Antoni; Cillóniz, Catia; Straube, Eberhard; Autenrieth, Ingo B.; Keller, Peter M.

2014-01-01

Severe pneumonia remains an important cause of morbidity and mortality. Polymerase chain reaction (PCR) has been shown to be more sensitive than current standard microbiological methods – particularly in patients with prior antibiotic treatment – and therefore, may improve the accuracy of microbiological diagnosis for hospitalized patients with pneumonia. Conventional detection techniques and multiplex PCR for 14 typical bacterial pneumonia-associated pathogens were performed on respiratory samples collected from adult hospitalized patients enrolled in a prospective multi-center study. Patients were enrolled from March until September 2012. A total of 739 fresh, native samples were eligible for analysis, of which 75 were sputa, 421 aspirates, and 234 bronchial lavages. 276 pathogens were detected by microbiology for which a valid PCR result was generated (positive or negative detection result by Curetis prototype system). Among these, 120 were identified by the prototype assay, 50 pathogens were not detected. Overall performance of the prototype for pathogen identification was 70.6% sensitivity (95% confidence interval (CI) lower bound: 63.3%, upper bound: 76.9%) and 95.2% specificity (95% CI lower bound: 94.6%, upper bound: 95.7%). Based on the study results, device cut-off settings were adjusted for future series production. The overall performance with the settings of the CE series production devices was 78.7% sensitivity (95% CI lower bound: 72.1%) and 96.6% specificity (95% CI lower bound: 96.1%). Time to result was 5.2 hours (median) for the prototype test and 43.5 h for standard-of-care. The Pneumonia Application provides a rapid and moderately sensitive assay for the detection of pneumonia-causing pathogens with minimal hands-on time. Trial Registration Deutsches Register Klinischer Studien (DRKS) DRKS00005684 PMID:25397673

For the Problem of Knowledge of the Universe

NASA Astrophysics Data System (ADS)

Kalanov, Temur Z.

2003-04-01

A new approach to the problem of knowledge of the Universe is suggested. This approach represents the new point of view which has arisen from the critical analysis of the foundations of physics, cosmology and philosophy (dialectical materialism). The principal idea following from the analysis is that only concepts (categories) and principles of dialectics are a basis of the correct theory of the Universe. The foundation of the correct theory is represented by the following philosophical principles. (a) The principle of materiality (objective reality) of the Nature: the Nature (Universe) is a system (set) of material objects (particles, bodies, fields). (b) The principle of existence of material object: an object exists as the objective reality, and movement is a form of existence of object. (c) The principle (definition) of movement of object: the movement is change (i.e. transition of some states into others) in general; the movement determines a direction, and direction characterizes the movement. (d) The principle of existence of time: the time exist as the parameter of the system of reference. (e) The principle of unity of opposites. (In particular, it means that the opposites are bounds of each other. In other words, if a class is divided into two non intersecting (opposite) subclasses, then each subclass is a bound another). (f) System principle: the properties of the system are not logical consequence, corollary of the properties of the elements of the system. These principles result in the following main statements about the Nature (Universe). The Universe does not contain subset of non objects (i.e. empty subset). Therefore, in accordance with (e), the Universe has no objective bound. It means that size (radius), mass, energy are not parameters of the Universe (i.e. size, mass, energy have physical meaning only in the case of limited objects). Consequences. (1) The generally accepted theories of evolution of the Universe (for example, Big Bang Theory) are incorrect if they contain the assumption of existence of the bound of the Universe (i.e. if concepts of singular state of the Universe, of expending or compressing of the Universe, of stability or instability of the Universe underlie the theories). (2) The principle of movement of the Universe: the movement of the Universe is represented by birth and extermination of objects and, consequently, change of structure of the Universe as a system. In particular, it means that there exist copies of objects. (In fact, the principle of identity of quantum particles of the same kind (for example, electrons) is a form of manifestation (consequence) of the principle of birth and extermination of objects). (3) The principle of movement of the Universe is a form of manifestation of the principle of development of the Universe (Nature). (4) The principle of development of the Universe (Nature) is a form of manifestation of the principle of existence of Unitary (i.e. of God). (5) The principle of existence of Unitary (God): Unitary (God) exists as the dialectical unity, identity of the opposites the real (material) and non real (non material) aspects of Unitary. (6) The principle of existence of Unitary (God) represents principal point of a new dialectical gnosiology (i.e. theory of knowledge). (7) Dialectical unity, identity of human practice and of human non practice (i.e. of human ethics based on comprehension of existence of God) is the criterion human truth. (8) The criterion of human truth determines a true way of knowledge of the Nature (Universe). (9) A bound of human knowledge and of human development is determined by development principle. (10) The existence of the bound of human development means existence of the bound only between Mankind and non Mankind (i.e. Supreme Intellect). Hence, the end of evolution of Mankind means transition, transformation, transmutation, dissolution of Mankind into Supreme Intellect. The comprehension of existence of Supreme Intellect around us will mean a beginning of contact, of dialogue with it.

Pioneer Venus orbiter search for Venusian lightning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borucki, W.J.; Dyer, J.W.; Phillips, J.R.

1991-07-01

During the 1988 and 1990, the star sensor aboard the Pioneer Venus orbiter (PVO) was used to search for optical pulses from lightning on the nightside of Venus. Useful data were obtained for 53 orbits in 1988 and 55 orbits in 1990. During this period, approximately 83 s of search time plus 7749 s of control data were obtained. The results again find no optical evidence for lightning activity. With the region that was observed during 1988, the results imply that the upper bound to short-duration flashes is 4 {times} 10{sup {minus}7} flashes/km{sup 2}/s for flashes that are at leastmore » 50% as bright as typical terrestrial lightning. During 1990, when the 2-Hz filter was used, the results imply an upper bound of 1 {times} 10{sup {minus}7} flashes/km{sup 2}/s for long-duration flashes at least 1.6% as bright as typical terrestrial lightning flashes or 33% as bright as the pulses observed by the Venera 9. The upper bounds to the flash rates for the 1988 and 1990 searches are twice and one half the global terrestrial rate, respectively. These two searches covered the region from 60{degrees}N latitude to 30{degrees}S latitude, 250{degrees} to 350{degrees} longitude, and the region from 45{degrees}N latitude to 55{degrees}S latitude, 155{degrees} to 300{degrees} longitude. Both searches sampled much of the nightside region from the dawn terminator to within 4 hours of the dusk terminator. These searches covered a much larger latitude range than any previous search. The results show that the Beat and Phoebe Regio areas previously identified by Russell et al. (1988) as areas with high rates of lightning activity were not active during the two seasons of the observations. When the authors assume that their upper bounds to the nightside flash rate are representative of the entire planet, the results imply that the global flash rate and energy dissipation rate derived by Krasnopol'sky (1983) from his observation of a single storm are too high.« less

NASA’s MAVEN Mission Observes Ups and Downs of Water Escape from Mars

NASA Image and Video Library

2017-12-08

After investigating the upper atmosphere of the Red Planet for a full Martian year, NASA’s MAVEN mission has determined that the escaping water does not always go gently into space. Sophisticated measurements made by a suite of instruments on the Mars Atmosphere and Volatile Evolution, or MAVEN, spacecraft revealed the ups and downs of hydrogen escape – and therefore water loss. The escape rate peaked when Mars was at its closest point to the sun and dropped off when the planet was farthest from the sun. The rate of loss varied dramatically overall, with 10 times more hydrogen escaping at the maximum. “MAVEN is giving us unprecedented detail about hydrogen escape from the upper atmosphere of Mars, and this is crucial for helping us figure out the total amount of water lost over billions of years,” said Ali Rahmati, a MAVEN team member at the University of California at Berkeley who analyzed data from two of the spacecraft’s instruments. Hydrogen in Mars’ upper atmosphere comes from water vapor in the lower atmosphere. An atmospheric water molecule can be broken apart by sunlight, releasing the two hydrogen atoms from the oxygen atom that they had been bound to. Several processes at work in Mars’ upper atmosphere may then act on the hydrogen, leading to its escape. Read more: go.nasa.gov/2dAgAV4 NASA image use policy. 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 Like us on Facebook Find us on Instagram

Standard representation and unified stability analysis for dynamic artificial neural network models.

PubMed

Kim, Kwang-Ki K; Patrón, Ernesto Ríos; Braatz, Richard D

2018-02-01

An overview is provided of dynamic artificial neural network models (DANNs) for nonlinear dynamical system identification and control problems, and convex stability conditions are proposed that are less conservative than past results. The three most popular classes of dynamic artificial neural network models are described, with their mathematical representations and architectures followed by transformations based on their block diagrams that are convenient for stability and performance analyses. Classes of nonlinear dynamical systems that are universally approximated by such models are characterized, which include rigorous upper bounds on the approximation errors. A unified framework and linear matrix inequality-based stability conditions are described for different classes of dynamic artificial neural network models that take additional information into account such as local slope restrictions and whether the nonlinearities within the DANNs are odd. A theoretical example shows reduced conservatism obtained by the conditions. Copyright © 2017. Published by Elsevier Ltd.

High redshift signatures in the 21 cm forest due to cosmic string wakes

NASA Astrophysics Data System (ADS)

Tashiro, Hiroyuki; Sekiguchi, Toyokazu; Silk, Joseph

2014-01-01

Cosmic strings induce minihalo formation in the early universe. The resultant minihalos cluster in string wakes and create a ``21 cm forest'' against the cosmic microwave background (CMB) spectrum. Such a 21 cm forest can contribute to angular fluctuations of redshifted 21 cm signals integrated along the line of sight. We calculate the root-mean-square amplitude of the 21 cm fluctuations due to strings and show that these fluctuations can dominate signals from minihalos due to primordial density fluctuations at high redshift (zgtrsim10), even if the string tension is below the current upper bound, Gμ < 1.5 × 10-7. Our results also predict that the Square Kilometre Array (SKA) can potentially detect the 21 cm fluctuations due to strings with Gμ ≈ 7.5 × 10-8 for the single frequency band case and 4.0 × 10-8 for the multi-frequency band case.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bazavov, A.; Ding, H. -T.; Hegde, P.

In this paper, we investigate the phase structure of QCD with three degenerate quark flavors as a function of the degenerate quark masses at vanishing baryon number density. We use the highly improved staggered quarks on lattices with temporal extent N τ = 6 and perform calculations for six values of quark masses, which in the continuum limit correspond to pion masses in the range 80 MeV ≲ m π ≲ 230 MeV. By analyzing the volume and temperature dependence of the chiral condensate and chiral susceptibility, we find no direct evidence for a first-order phase transition in this rangemore » of pion mass values. Finally, relying on the universal scaling behaviors of the chiral observables near an anticipated chiral critical point, we estimate an upper bound for the critical pion mass m c π ≲ 50 MeV, below which a region of first-order chiral phase transition is favored.« less

Postinflationary vacuum instability and Higgs-inflaton couplings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Enqvist, Kari; Karčiauskas, Mindaugas; Lebedev, Oleg

2016-11-11

The Higgs-inflaton coupling plays an important role in the Higgs field dynamics in the early Universe. Even a tiny coupling generated at loop level can have a dramatic effect on the fate of the electroweak vacuum. Such Higgs-inflaton interaction is present both at the trilinear and quartic levels in realistic reheating models. In this work, we examine the Higgs dynamics during the preheating epoch, focusing on the effects of the parametric and tachyonic resonances. We use lattice simulations and other numerical tools in our studies. We find that the resonances can induce large fluctuations of the Higgs field which destabilizemore » the electroweak vacuum. Our considerations thus provide an upper bound on quartic and trilinear interactions between the Higgs and the inflaton. We conclude that there exists a favorable range of the couplings within which the Higgs field is stabilized during both inflation and preheating epochs.« less

Alder Establishment and Channel Dynamics in a Tributary of the South Fork Eel River, Mendocino County, California

Treesearch

William J. Trush; Edward C. Connor; Knight Alan W.

1989-01-01

Riparian communities established along Elder Creek, a tributary of the upper South Fork Eel River, are bounded by two frequencies of periodic flooding. The upper limit for the riparian zone occurs at bankfull stage. The lower riparian limit is associated with a more frequent stage height, called the active channel, having an exceedance probability of 11 percent on a...

Variational bounds on the temperature distribution

NASA Astrophysics Data System (ADS)

Kalikstein, Kalman; Spruch, Larry; Baider, Alberto

1984-02-01

Upper and lower stationary or variational bounds are obtained for functions which satisfy parabolic linear differential equations. (The error in the bound, that is, the difference between the bound on the function and the function itself, is of second order in the error in the input function, and the error is of known sign.) The method is applicable to a range of functions associated with equalization processes, including heat conduction, mass diffusion, electric conduction, fluid friction, the slowing down of neutrons, and certain limiting forms of the random walk problem, under conditions which are not unduly restrictive: in heat conduction, for example, we do not allow the thermal coefficients or the boundary conditions to depend upon the temperature, but the thermal coefficients can be functions of space and time and the geometry is unrestricted. The variational bounds follow from a maximum principle obeyed by the solutions of these equations.

Long-distance measurement-device-independent quantum key distribution with coherent-state superpositions.

PubMed

Yin, H-L; Cao, W-F; Fu, Y; Tang, Y-L; Liu, Y; Chen, T-Y; Chen, Z-B

2014-09-15

Measurement-device-independent quantum key distribution (MDI-QKD) with decoy-state method is believed to be securely applied to defeat various hacking attacks in practical quantum key distribution systems. Recently, the coherent-state superpositions (CSS) have emerged as an alternative to single-photon qubits for quantum information processing and metrology. Here, in this Letter, CSS are exploited as the source in MDI-QKD. We present an analytical method that gives two tight formulas to estimate the lower bound of yield and the upper bound of bit error rate. We exploit the standard statistical analysis and Chernoff bound to perform the parameter estimation. Chernoff bound can provide good bounds in the long-distance MDI-QKD. Our results show that with CSS, both the security transmission distance and secure key rate are significantly improved compared with those of the weak coherent states in the finite-data case.

Universal bounds on charged states in 2d CFT and 3d gravity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benjamin, Nathan; Dyer, Ethan; Fitzpatrick, A. Liam

2016-08-04

We derive an explicit bound on the dimension of the lightest charged state in two dimensional conformal field theories with a global abelian symmetry. We find that the bound scales with c and provide examples that parametrically saturate this bound. We also prove that any such theory must contain a state with charge-to-mass ratio above a minimal lower bound. As a result, we comment on the implications for charged states in three dimensional theories of gravity.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, E.B. Jr.

Various methods for the calculation of lower bounds for eigenvalues are examined, including those of Weinstein, Temple, Bazley and Fox, Gay, and Miller. It is shown how all of these can be derived in a unified manner by the projection technique. The alternate forms obtained for the Gay formula show how a considerably improved method can be readily obtained. Applied to the ground state of the helium atom with a simple screened hydrogenic trial function, this new method gives a lower bound closer to the true energy than the best upper bound obtained with this form of trial function. Possiblemore » routes to further improved methods are suggested.« less

Upper Bounds on the Expected Value of a Convex Function Using Gradient and Conjugate Function Information.

DTIC Science & Technology

1987-08-01

of the absolute difference between the random variable and its mean.Gassmann and Ziemba 119861 provide a weaker bound that does not require...2.8284, and EX4tV) -12 EX’iX) = -42. Hence C = -2 -€t* i-4’]= I-- . 1213. £1 2 5 COMPARISONS OF BOUNDS IN IIn Gassmann and Ziemba 11986) extend an idea...solution of the foLLowing Linear program: (see Gassmann, Ziemba (1986),Theorem 1) m m m-GZ=max(XT(vi) I: z. 1=1,Z vo=x io (5.1hk i-l i=i i=1 I I where 0

Bounds on Block Error Probability for Multilevel Concatenated Codes

NASA Technical Reports Server (NTRS)

Lin, Shu; Moorthy, Hari T.; Stojanovic, Diana

1996-01-01

Maximum likelihood decoding of long block codes is not feasable due to large complexity. Some classes of codes are shown to be decomposable into multilevel concatenated codes (MLCC). For these codes, multistage decoding provides good trade-off between performance and complexity. In this paper, we derive an upper bound on the probability of block error for MLCC. We use this bound to evaluate difference in performance for different decompositions of some codes. Examples given show that a significant reduction in complexity can be achieved when increasing number of stages of decoding. Resulting performance degradation varies for different decompositions. A guideline is given for finding good m-level decompositions.

New Anomalous Lieb-Robinson Bounds in Quasiperiodic XY Chains

NASA Astrophysics Data System (ADS)

Damanik, David; Lemm, Marius; Lukic, Milivoje; Yessen, William

2014-09-01

We announce and sketch the rigorous proof of a new kind of anomalous (or sub-ballistic) Lieb-Robinson (LR) bound for an isotropic XY chain in a quasiperiodic transversal magnetic field. Instead of the usual effective light cone |x|≤v|t|, we obtain |x|≤v|t|α for some 0<α <1. We can characterize the allowed values of α exactly as those exceeding the upper transport exponent αu+ of a one-body Schrödinger operator. To our knowledge, this is the first rigorous derivation of anomalous quantum many-body transport. We also discuss anomalous LR bounds with power-law tails for a random dimer field.

Precision Measurement of the Electron's Electric Dipole Moment Using Trapped Molecular Ions

NASA Astrophysics Data System (ADS)

Cairncross, William B.; Gresh, Daniel N.; Grau, Matt; Cossel, Kevin C.; Roussy, Tanya S.; Ni, Yiqi; Zhou, Yan; Ye, Jun; Cornell, Eric A.

2017-10-01

We describe the first precision measurement of the electron's electric dipole moment (de) using trapped molecular ions, demonstrating the application of spin interrogation times over 700 ms to achieve high sensitivity and stringent rejection of systematic errors. Through electron spin resonance spectroscopy on 180Hf 19F+ in its metastable 3Δ1 electronic state, we obtain de=(0.9 ±7. 7stat±1. 7syst)×10-29 e cm , resulting in an upper bound of |de|<1.3 ×10-28 e cm (90% confidence). Our result provides independent confirmation of the current upper bound of |de|<9.4 ×10-29 e cm [J. Baron et al., New J. Phys. 19, 073029 (2017), 10.1088/1367-2630/aa708e], and offers the potential to improve on this limit in the near future.

Limit cycles via higher order perturbations for some piecewise differential systems

NASA Astrophysics Data System (ADS)

Buzzi, Claudio A.; Lima, Maurício Firmino Silva; Torregrosa, Joan

2018-05-01

A classical perturbation problem is the polynomial perturbation of the harmonic oscillator, (x‧ ,y‧) =(- y + εf(x , y , ε) , x + εg(x , y , ε)) . In this paper we study the limit cycles that bifurcate from the period annulus via piecewise polynomial perturbations in two zones separated by a straight line. We prove that, for polynomial perturbations of degree n , no more than Nn - 1 limit cycles appear up to a study of order N. We also show that this upper bound is reached for orders one and two. Moreover, we study this problem in some classes of piecewise Liénard differential systems providing better upper bounds for higher order perturbation in ε, showing also when they are reached. The Poincaré-Pontryagin-Melnikov theory is the main technique used to prove all the results.

Non-localization of eigenfunctions for Sturm-Liouville operators and applications

NASA Astrophysics Data System (ADS)

Liard, Thibault; Lissy, Pierre; Privat, Yannick

2018-02-01

In this article, we investigate a non-localization property of the eigenfunctions of Sturm-Liouville operators Aa = -∂xx + a (ṡ) Id with Dirichlet boundary conditions, where a (ṡ) runs over the bounded nonnegative potential functions on the interval (0 , L) with L > 0. More precisely, we address the extremal spectral problem of minimizing the L2-norm of a function e (ṡ) on a measurable subset ω of (0 , L), where e (ṡ) runs over all eigenfunctions of Aa, at the same time with respect to all subsets ω having a prescribed measure and all L∞ potential functions a (ṡ) having a prescribed essentially upper bound. We provide some existence and qualitative properties of the minimizers, as well as precise lower and upper estimates on the optimal value. Several consequences in control and stabilization theory are then highlighted.

Fisher information of a single qubit interacts with a spin-qubit in the presence of a magnetic field

NASA Astrophysics Data System (ADS)

Metwally, N.

2018-06-01

In this contribution, quantum Fisher information is utilized to estimate the parameters of a central qubit interacting with a single-spin qubit. The effect of the longitudinal, transverse and the rotating strengths of the magnetic field on the estimation degree is discussed. It is shown that, in the resonance case, the number of peaks and consequently the size of the estimation regions increase as the rotating magnetic field strength increases. The precision estimation of the central qubit parameters depends on the initial state settings of the central and the spin-qubit, either encode classical or quantum information. It is displayed that, the upper bounds of the estimation degree are large if the two qubits encode classical information. In the non-resonance case, the estimation degree depends on which of the longitudinal/transverse strength is larger. The coupling constant between the central qubit and the spin-qubit has a different effect on the estimation degree of the weight and the phase parameters, where the possibility of estimating the weight parameter decreases as the coupling constant increases, while it increases for the phase parameter. For large number of spin-particles, namely, we have a spin-bath particles, the upper bounds of the Fisher information with respect to the weight parameter of the central qubit decreases as the number of the spin particle increases. As the interaction time increases, the upper bounds appear at different initial values of the weight parameter.

Simplest little Higgs model revisited: Hidden mass relation, unitarity, and naturalness

NASA Astrophysics Data System (ADS)

Cheung, Kingman; He, Shi-Ping; Mao, Ying-nan; Zhang, Chen; Zhou, Yang

2018-06-01

We analyze the scalar potential of the simplest little Higgs (SLH) model in an approach consistent with the spirit of continuum effective field theory (CEFT). By requiring correct electroweak symmetry breaking (EWSB) with the 125 GeV Higgs boson, we are able to derive a relation between the pseudoaxion mass mη and the heavy top mass mT, which serves as a crucial test of the SLH mechanism. By requiring mη2>0 an upper bound on mT can be obtained for any fixed SLH global symmetry breaking scale f . We also point out that an absolute upper bound on f can be obtained by imposing partial wave unitarity constraint, which in turn leads to absolute upper bounds of mT≲19 TeV , mη≲1.5 TeV , and mZ'≲48 TeV . We present the allowed region in the three-dimensional parameter space characterized by f ,tβ,mT, taking into account the requirement of valid EWSB and the constraint from perturbative unitarity. We also propose a strategy of analyzing the fine-tuning problem consistent with the spirit of CEFT and apply it to the SLH. We suggest that the scalar potential and fine-tuning analysis strategies adopted here should also be applicable to a wide class of little Higgs and twin Higgs models, which may reveal interesting relations as crucial tests of the related EWSB mechanism and provide a new perspective on assessing their degree of fine-tuning.

Bounds on OPE coefficients from interference effects in the conformal collider

NASA Astrophysics Data System (ADS)

Córdova, Clay; Maldacena, Juan; Turiaci, Gustavo J.

2017-11-01

We apply the average null energy condition to obtain upper bounds on the three-point function coefficients of stress tensors and a scalar operator, < TTOi>, in general CFTs. We also constrain the gravitational anomaly of U(1) currents in four-dimensional CFTs, which are encoded in three-point functions of the form 〈 T T J 〉. In theories with a large N AdS dual we translate these bounds into constraints on the coefficient of a higher derivative bulk term of the form ∫ϕ W 2. We speculate that these bounds also apply in de-Sitter. In this case our results constrain inflationary observables, such as the amplitude for chiral gravity waves that originate from higher derivative terms in the Lagrangian of the form ϕ W W ∗.

Reduced conservatism in stability robustness bounds by state transformation

NASA Technical Reports Server (NTRS)

Yedavalli, R. K.; Liang, Z.

1986-01-01

This note addresses the issue of 'conservatism' in the time domain stability robustness bounds obtained by the Liapunov approach. A state transformation is employed to improve the upper bounds on the linear time-varying perturbation of an asymptotically stable linear time-invariant system for robust stability. This improvement is due to the variance of the conservatism of the Liapunov approach with respect to the basis of the vector space in which the Liapunov function is constructed. Improved bounds are obtained, using a transformation, on elemental and vector norms of perturbations (i.e., structured perturbations) as well as on a matrix norm of perturbations (i.e., unstructured perturbations). For the case of a diagonal transformation, an algorithm is proposed to find the 'optimal' transformation. Several examples are presented to illustrate the proposed analysis.

Generalized Hofmann quantum process fidelity bounds for quantum filters

NASA Astrophysics Data System (ADS)

Sedlák, Michal; Fiurášek, Jaromír

2016-04-01

We propose and investigate bounds on the quantum process fidelity of quantum filters, i.e., probabilistic quantum operations represented by a single Kraus operator K . These bounds generalize the Hofmann bounds on the quantum process fidelity of unitary operations [H. F. Hofmann, Phys. Rev. Lett. 94, 160504 (2005), 10.1103/PhysRevLett.94.160504] and are based on probing the quantum filter with pure states forming two mutually unbiased bases. Determination of these bounds therefore requires far fewer measurements than full quantum process tomography. We find that it is particularly suitable to construct one of the probe bases from the right eigenstates of K , because in this case the bounds are tight in the sense that if the actual filter coincides with the ideal one, then both the lower and the upper bounds are equal to 1. We theoretically investigate the application of these bounds to a two-qubit optical quantum filter formed by the interference of two photons on a partially polarizing beam splitter. For an experimentally convenient choice of factorized input states and measurements we study the tightness of the bounds. We show that more stringent bounds can be obtained by more sophisticated processing of the data using convex optimization and we compare our methods for different choices of the input probe states.

A Multi-Armed Bandit Approach to Following a Markov Chain

DTIC Science & Technology

2017-06-01

focus on the House to Café transition (p1,4). We develop a Multi-Armed Bandit approach for efficiently following this target, where each state takes the...and longitude (each state corresponding to a physical location and a small set of activities). The searcher would then apply our approach on this...the target’s transition probability and the true probability over time. Further, we seek to provide upper bounds (i.e., worst case bounds) on the

Hard and Soft Constraints in Reliability-Based Design Optimization

NASA Technical Reports Server (NTRS)

Crespo, L.uis G.; Giesy, Daniel P.; Kenny, Sean P.

2006-01-01

This paper proposes a framework for the analysis and design optimization of models subject to parametric uncertainty where design requirements in the form of inequality constraints are present. Emphasis is given to uncertainty models prescribed by norm bounded perturbations from a nominal parameter value and by sets of componentwise bounded uncertain variables. These models, which often arise in engineering problems, allow for a sharp mathematical manipulation. Constraints can be implemented in the hard sense, i.e., constraints must be satisfied for all parameter realizations in the uncertainty model, and in the soft sense, i.e., constraints can be violated by some realizations of the uncertain parameter. In regard to hard constraints, this methodology allows (i) to determine if a hard constraint can be satisfied for a given uncertainty model and constraint structure, (ii) to generate conclusive, formally verifiable reliability assessments that allow for unprejudiced comparisons of competing design alternatives and (iii) to identify the critical combination of uncertain parameters leading to constraint violations. In regard to soft constraints, the methodology allows the designer (i) to use probabilistic uncertainty models, (ii) to calculate upper bounds to the probability of constraint violation, and (iii) to efficiently estimate failure probabilities via a hybrid method. This method integrates the upper bounds, for which closed form expressions are derived, along with conditional sampling. In addition, an l(sub infinity) formulation for the efficient manipulation of hyper-rectangular sets is also proposed.

How fast can a black hole rotate?

NASA Astrophysics Data System (ADS)

Herdeiro, Carlos A. R.; Radu, Eugen

2015-11-01

Kerr black holes (BHs) have their angular momentum, J, bounded by their mass, M: Jc ≤ GM2. There are, however, known BH solutions violating this Kerr bound. We propose a very simple universal bound on the rotation, rather than on the angular momentum, of four-dimensional, stationary and axisymmetric, asymptotically flat BHs, given in terms of an appropriately defined horizon linear velocity, vH. The vH bound is simply that vH cannot exceed the velocity of light. We verify the vH bound for known BH solutions, including some that violate the Kerr bound, and conjecture that only extremal Kerr BHs saturate the vH bound.

Lepton-flavor universality limits in warped space

NASA Astrophysics Data System (ADS)

Megías, Eugenio; Quirós, Mariano; Salas, Lindber

2017-10-01

We explore the limits on lepton-flavor universality (LFU) violation in theories where the hierarchy problem is solved by means of a warped extra dimension. In those theories, LFU violation, in fermion interaction with Kaluza-Klein modes of gauge bosons, is provided ab initio when different flavors of fermions are differently localized along the extra dimension. As this fact arises from the mass pattern of quarks and leptons, LFU violation is natural in this class of theories. We analyze the experimental data pointing toward LFU violation, as well as the most relevant electroweak and flavor observables, and the LFU tests in the μ /e and τ /μ sectors. We find agreement with RK(*) and RD(*) data at 95% C.L., provided the third-generation left-handed fermions are composite (0.14

Dark Coulomb binding of heavy neutrinos of fourth family

NASA Astrophysics Data System (ADS)

Belotsky, K. M.; Esipova, E. A.; Khlopov, M. Yu.; Laletin, M. N.

2015-11-01

Direct dark matter searches put severe constraints on the weakly interacting massive particles (WIMPs). These constraints cause serious troubles for the model of stable neutrino of fourth generation with mass around 50GeV. Though the calculations of primordial abundance of these particles make them in the charge symmetric case a sparse subdominant component of the modern dark matter, their presence in the universe would exceed the current upper limits by several orders of the magnitude. However, if quarks and leptons of fourth generation possess their own Coulomb-like y-interaction, recombination of pairs of heavy neutrinos and antineutrinos and their annihilation in the “neutrinium” atoms can play important role in their cosmological evolution, reducing their modern abundance far below the experimental upper limits. The model of stable fourth generation assumes that the dominant part of dark matter is explained by excessive Ū antiquarks, forming (ŪŪŪ)-- charged clusters, bound with primordial helium in nuclear-interacting O-helium (OHe) dark atoms. The y charge conservation implies generation of the same excess of fourth generation neutrinos, potentially dangerous WIMP component of this scenario. We show that due to y-interaction recombination of fourth neutrinos with OHe hides these WIMPs from direct WIMP searches, leaving the negligible fraction of free neutrinos, what makes their existence compatible with the experimental constraints.

Ionospheric Signatures in Radio Occultation Data

NASA Technical Reports Server (NTRS)

Mannucci, Anthony J.; Ao, Chi; Iijima, Byron A.; Kursinkski, E. Robert

2012-01-01

We can extend robustly the radio occultation data record by 6 years (+60%) by developing a singlefrequency processing method for GPS/MET data. We will produce a calibrated data set with profile-byprofile data characterization to determine robust upper bounds on ionospheric bias. Part of an effort to produce a calibrated RO data set addressing other key error sources such as upper boundary initialization. Planned: AIRS-GPS water vapor cross validation (water vapor climatology and trends).

Historic Landscape Plan University of Florida Campus, Plaza of ...

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

Historic Landscape Plan - University of Florida Campus, Plaza of the Americas, University of Florida Campus Quad Bounded by West University Avenue, US 441/Southwest 13th Street, Stadium Road, and North-South Drive, Gainesville, Alachua County, FL

Testing ΛCDM cosmology at turnaround: where to look for violations of the bound?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanoglidis, D.; Pavlidou, V.; Tomaras, T.N., E-mail: dtanogl@physics.uoc.gr, E-mail: pavlidou@physics.uoc.gr, E-mail: tomaras@physics.uoc.gr

In ΛCDM cosmology, structure formation is halted shortly after dark energy dominates the mass/energy budget of the Universe. A manifestation of this effect is that in such a cosmology the turnaround radius—the non-expanding mass shell furthest away from the center of a structure— has an upper bound. Recently, a new, local, test for the existence of dark energy in the form of a cosmological constant was proposed based on this turnaround bound. Before designing an experiment that, through high-precision determination of masses and —independently— turnaround radii, will challenge ΛCDM cosmology, we have to answer two important questions: first, when turnaround-scalemore » structures are predicted to be close enough to their maximum size, so that a possible violation of the bound may be observable. Second, which is the best mass scale to target for possible violations of the bound. These are the questions we address in the present work. Using the Press-Schechter formalism, we find that turnaround structures have in practice already stopped forming, and consequently, the turnaround radius of structures must be very close to the maximum value today. We also find that the mass scale of ∼ 10{sup 13} M{sub ⊙} characterizes the turnaround structures that start to form in a statistically important number density today —and even at an infinite time in the future, since structure formation has almost stopped. This mass scale also separates turnaround structures with qualitatively different cosmological evolution: smaller structures are no longer readjusting their mass distribution inside the turnaround scale, they asymptotically approach their ultimate abundance from higher values, and they are common enough to have, at some epoch, experienced major mergers with structures of comparable mass; larger structures exhibit the opposite behavior. We call this mass scale the transitional mass scale and we argue that it is the optimal for the purpose outlined above. As a corollary, we explain the different accretion behavior of small and larger structures observed in already conducted numerical simulations.« less

New bounding and decomposition approaches for MILP investment problems: Multi-area transmission and generation planning under policy constraints

DOE PAGES

Munoz, F. D.; Hobbs, B. F.; Watson, J. -P.

2016-02-01

A novel two-phase bounding and decomposition approach to compute optimal and near-optimal solutions to large-scale mixed-integer investment planning problems is proposed and it considers a large number of operating subproblems, each of which is a convex optimization. Our motivating application is the planning of power transmission and generation in which policy constraints are designed to incentivize high amounts of intermittent generation in electric power systems. The bounding phase exploits Jensen’s inequality to define a lower bound, which we extend to stochastic programs that use expected-value constraints to enforce policy objectives. The decomposition phase, in which the bounds are tightened, improvesmore » upon the standard Benders’ algorithm by accelerating the convergence of the bounds. The lower bound is tightened by using a Jensen’s inequality-based approach to introduce an auxiliary lower bound into the Benders master problem. Upper bounds for both phases are computed using a sub-sampling approach executed on a parallel computer system. Numerical results show that only the bounding phase is necessary if loose optimality gaps are acceptable. But, the decomposition phase is required to attain optimality gaps. Moreover, use of both phases performs better, in terms of convergence speed, than attempting to solve the problem using just the bounding phase or regular Benders decomposition separately.« less

New bounding and decomposition approaches for MILP investment problems: Multi-area transmission and generation planning under policy constraints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Munoz, F. D.; Hobbs, B. F.; Watson, J. -P.

A novel two-phase bounding and decomposition approach to compute optimal and near-optimal solutions to large-scale mixed-integer investment planning problems is proposed and it considers a large number of operating subproblems, each of which is a convex optimization. Our motivating application is the planning of power transmission and generation in which policy constraints are designed to incentivize high amounts of intermittent generation in electric power systems. The bounding phase exploits Jensen’s inequality to define a lower bound, which we extend to stochastic programs that use expected-value constraints to enforce policy objectives. The decomposition phase, in which the bounds are tightened, improvesmore » upon the standard Benders’ algorithm by accelerating the convergence of the bounds. The lower bound is tightened by using a Jensen’s inequality-based approach to introduce an auxiliary lower bound into the Benders master problem. Upper bounds for both phases are computed using a sub-sampling approach executed on a parallel computer system. Numerical results show that only the bounding phase is necessary if loose optimality gaps are acceptable. But, the decomposition phase is required to attain optimality gaps. Moreover, use of both phases performs better, in terms of convergence speed, than attempting to solve the problem using just the bounding phase or regular Benders decomposition separately.« less

Fluorescence photon migration techniques for the on-farm measurement of somatic cell count in fresh cow's milk

NASA Astrophysics Data System (ADS)

Khoo, Geoffrey; Kuennemeyer, Rainer; Claycomb, Rod W.

2005-04-01

Currently, the state of the art of mastitis detection in dairy cows is the laboratory-based measurement of somatic cell count (SCC), which is time consuming and expensive. Alternative, rapid, and reliable on-farm measurement methods are required for effective farm management. We have investigated whether fluorescence lifetime measurements can determine SCC in fresh, unprocessed milk. The method is based on the change in fluorescence lifetime of ethidium bromide when it binds to DNA from the somatic cells. Milk samples were obtained from a Fullwood Merlin Automated Milking System and analysed within a twenty-four hour period, over which the SCC does not change appreciably. For reference, the milk samples were also sent to a testing laboratory where the SCC was determined by traditional methods. The results show that we can quantify SCC using the fluorescence photon migration method from a lower bound of 4x105 cells mL-1 to an upper bound of 1 x 107 cells mL-1. The upper bound is due to the reference method used while the cause of the lower boundary is unknown, yet.

Record length requirement of long-range dependent teletraffic

NASA Astrophysics Data System (ADS)

Li, Ming

2017-04-01

This article contributes the highlights mainly in two folds. On the one hand, it presents a formula to compute the upper bound of the variance of the correlation periodogram measurement of teletraffic (traffic for short) with long-range dependence (LRD) for a given record length T and a given value of the Hurst parameter H (Theorems 1 and 2). On the other hand, it proposes two formulas for the computation of the variance upper bound of the correlation periodogram measurement of traffic of fractional Gaussian noise (fGn) type and the generalized Cauchy (GC) type, respectively (Corollaries 1 and 2). They may constitute a reference guideline of record length requirement of traffic with LRD. In addition, record length requirement for the correlation periodogram measurement of traffic with either the Schuster type or the Bartlett one is studied and the present results about it show that both types of periodograms may be used for the correlation measurement of traffic with a pre-desired variance bound of correlation estimation. Moreover, real traffic in the Internet Archive by the Special Interest Group on Data Communication under the Association for Computing Machinery of US (ACM SIGCOMM) is analyzed in the case study in this topic.

Improving the efficiency of single and multiple teleportation protocols based on the direct use of partially entangled states

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fortes, Raphael; Rigolin, Gustavo, E-mail: rigolin@ifi.unicamp.br

We push the limits of the direct use of partially pure entangled states to perform quantum teleportation by presenting several protocols in many different scenarios that achieve the optimal efficiency possible. We review and put in a single formalism the three major strategies known to date that allow one to use partially entangled states for direct quantum teleportation (no distillation strategies permitted) and compare their efficiencies in real world implementations. We show how one can improve the efficiency of many direct teleportation protocols by combining these techniques. We then develop new teleportation protocols employing multipartite partially entangled states. The threemore » techniques are also used here in order to achieve the highest efficiency possible. Finally, we prove the upper bound for the optimal success rate for protocols based on partially entangled Bell states and show that some of the protocols here developed achieve such a bound. -- Highlights: •Optimal direct teleportation protocols using directly partially entangled states. •We put in a single formalism all strategies of direct teleportation. •We extend these techniques for multipartite partially entangle states. •We give upper bounds for the optimal efficiency of these protocols.« less

Performance analysis of optimal power allocation in wireless cooperative communication systems

NASA Astrophysics Data System (ADS)

Babikir Adam, Edriss E.; Samb, Doudou; Yu, Li

2013-03-01

Cooperative communication has been recently proposed in wireless communication systems for exploring the inherent spatial diversity in relay channels.The Amplify-and-Forward (AF) cooperation protocols with multiple relays have not been sufficiently investigated even if it has a low complexity in term of implementation. We consider in this work a cooperative diversity system in which a source transmits some information to a destination with the help of multiple relay nodes with AF protocols and investigate the optimality of allocating powers both at the source and the relays system by optimizing the symbol error rate (SER) performance in an efficient way. Firstly we derive a closedform SER formulation for MPSK signal using the concept of moment generating function and some statistical approximations in high signal to noise ratio (SNR) for the system under studied. We then find a tight corresponding lower bound which converges to the same limit as the theoretical upper bound and develop an optimal power allocation (OPA) technique with mean channel gains to minimize the SER. Simulation results show that our scheme outperforms the equal power allocation (EPA) scheme and is tight to the theoretical approximation based on the SER upper bound in high SNR for different number of relays.

Simulating the effect of vegetation cover on the sediment yield of mediterranean catchments using SHETRAN

NASA Astrophysics Data System (ADS)

Lukey, B. T.; Sheffield, J.; Bathurst, J. C.; Lavabre, J.; Mathys, N.; Martin, C.

1995-08-01

The sediment yield of two catchments in southern France was modelled using the newly developed sediment code of SHETRAN. A fire in August 1990 denuded the Rimbaud catchment, providing an opportunity to study the effect of vegetation cover on sediment yield by running the model for both pre-and post-fire cases. Model output is in the form of upper and lower bounds on sediment discharge, reflecting the uncertainty in the erodibility of the soil. The results are encouraging since measured sediment discharge falls largely between the predicted bounds, and simulated sediment yield is dramatically lower for the catchment before the fire which matches observation. SHETRAN is also applied to the Laval catchment, which is subject to Badlands gulley erosion. Again using the principle of generating upper and lower bounds on sediment discharge, the model is shown to be capable of predicting the bulk sediment discharge over periods of months. To simulate the effect of reforestation, the model is run with vegetation cover equivalent to a neighbouring fully forested basin. The results obtained indicate that SHETRAN provides a powerful tool for predicting the impact of environmental change and land management on sediment yield.

Existence and amplitude bounds for irrotational water waves in finite depth

NASA Astrophysics Data System (ADS)

Kogelbauer, Florian

2017-12-01

We prove the existence of solutions to the irrotational water-wave problem in finite depth and derive an explicit upper bound on the amplitude of the nonlinear solutions in terms of the wavenumber, the total hydraulic head, the wave speed and the relative mass flux. Our approach relies upon a reformulation of the water-wave problem as a one-dimensional pseudo-differential equation and the Newton-Kantorovich iteration for Banach spaces. This article is part of the theme issue 'Nonlinear water waves'.

Entanglement polygon inequality in qubit systems

NASA Astrophysics Data System (ADS)

Qian, Xiao-Feng; Alonso, Miguel A.; Eberly, J. H.

2018-06-01

We prove a set of tight entanglement inequalities for arbitrary N-qubit pure states. By focusing on all bi-partite marginal entanglements between each single qubit and its remaining partners, we show that the inequalities provide an upper bound for each marginal entanglement, while the known monogamy relation establishes the lower bound. The restrictions and sharing properties associated with the inequalities are further analyzed with a geometric polytope approach, and examples of three-qubit GHZ-class and W-class entangled states are presented to illustrate the results.

Quantum Speed Limits across the Quantum-to-Classical Transition

NASA Astrophysics Data System (ADS)

Shanahan, B.; Chenu, A.; Margolus, N.; del Campo, A.

2018-02-01

Quantum speed limits set an upper bound to the rate at which a quantum system can evolve. Adopting a phase-space approach, we explore quantum speed limits across the quantum-to-classical transition and identify equivalent bounds in the classical world. As a result, and contrary to common belief, we show that speed limits exist for both quantum and classical systems. As in the quantum domain, classical speed limits are set by a given norm of the generator of time evolution.

Bounds on the cross-correlation functions of state m-sequences

NASA Astrophysics Data System (ADS)

Woodcock, C. F.; Davies, Phillip A.; Shaar, Ahmed A.

1987-03-01

Lower and upper bounds on the peaks of the periodic Hamming cross-correlation function for state m-sequences, which are often used in frequency-hopped spread-spectrum systems, are derived. The state position mapped (SPM) sequences of the state m-sequences are described. The use of SPM sequences for OR-channel code division multiplexing is studied. The relation between the Hamming cross-correlation function and the correlation function of SPM sequence is examined. Numerical results which support the theoretical data are presented.

Hybrid Theory of Electron-Hydrogenic Systems Elastic Scattering

NASA Technical Reports Server (NTRS)

Bhatia, A. K.

2007-01-01

Accurate electron-hydrogen and electron-hydrogenic cross sections are required to interpret fusion experiments, laboratory plasma physics and properties of the solar and astrophysical plasmas. We have developed a method in which the short-range and long-range correlations can be included at the same time in the scattering equations. The phase shifts have rigorous lower bounds and the scattering lengths have rigorous upper bounds. The phase shifts in the resonance region can be used to calculate very accurately the resonance parameters.

DD-bar production and their interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Yanrui; Oka, Makoto; Takizawa, Makoto

2011-05-23

We have explored the bound state problem and the scattering problem of the DD-bar pair in a meson exchange model. When considering their production in the e{sup +}e{sup -} process, we included the DD-bar rescattering effect. Although it is difficult to answer whether the S-wave DD-bar bound state exists or not from the binding energies and the phase shifts, one may get an upper limit of the binding energy from the production of the BB-bar, the bottom analog of DD-bar.

Thin-wall approximation in vacuum decay: A lemma

NASA Astrophysics Data System (ADS)

Brown, Adam R.

2018-05-01

The "thin-wall approximation" gives a simple estimate of the decay rate of an unstable quantum field. Unfortunately, the approximation is uncontrolled. In this paper I show that there are actually two different thin-wall approximations and that they bracket the true decay rate: I prove that one is an upper bound and the other a lower bound. In the thin-wall limit, the two approximations converge. In the presence of gravity, a generalization of this lemma provides a simple sufficient condition for nonperturbative vacuum instability.

A Note on the Kirchhoff and Additive Degree-Kirchhoff Indices of Graphs

NASA Astrophysics Data System (ADS)

Yang, Yujun; Klein, Douglas J.

2015-06-01

Two resistance-distance-based graph invariants, namely, the Kirchhoff index and the additive degree-Kirchhoff index, are studied. A relation between them is established, with inequalities for the additive degree-Kirchhoff index arising via the Kirchhoff index along with minimum, maximum, and average degrees. Bounds for the Kirchhoff and additive degree-Kirchhoff indices are also determined, and extremal graphs are characterised. In addition, an upper bound for the additive degree-Kirchhoff index is established to improve a previously known result.

Magnitude error bounds for sampled-data frequency response obtained from the truncation of an infinite series, and compensator improvement program

NASA Technical Reports Server (NTRS)

Mitchell, J. R.

1972-01-01

The frequency response method of analyzing control system performance is discussed, and the difficulty of obtaining the sampled frequency response of the continuous system is considered. An upper bound magnitude error equation is obtained which yields reasonable estimates of the actual error. Finalization of the compensator improvement program is also reported, and the program was used to design compensators for Saturn 5/S1-C dry workshop and Saturn 5/S1-C Skylab.

On the boundedness and integration of non-oscillatory solutions of certain linear differential equations of second order.

PubMed

Tunç, Cemil; Tunç, Osman

2016-01-01

In this paper, certain system of linear homogeneous differential equations of second-order is considered. By using integral inequalities, some new criteria for bounded and [Formula: see text]-solutions, upper bounds for values of improper integrals of the solutions and their derivatives are established to the considered system. The obtained results in this paper are considered as extension to the results obtained by Kroopnick (2014) [1]. An example is given to illustrate the obtained results.

Blow-up of solutions to a quasilinear wave equation for high initial energy

NASA Astrophysics Data System (ADS)

Li, Fang; Liu, Fang

2018-05-01

This paper deals with blow-up solutions to a nonlinear hyperbolic equation with variable exponent of nonlinearities. By constructing a new control function and using energy inequalities, the authors obtain the lower bound estimate of the L2 norm of the solution. Furthermore, the concavity arguments are used to prove the nonexistence of solutions; at the same time, an estimate of the upper bound of blow-up time is also obtained. This result extends and improves those of [1,2].

Scenarios for gluino coannihilation

DOE PAGES

Ellis, John; Evans, Jason L.; Luo, Feng; ...

2016-02-11

In this article, we study supersymmetric scenarios in which the gluino is the next-to-lightest supersymmetric particle (NLSP), with a mass sufficiently close to that of the lightest supersymmetric particle (LSP) that gluino coannihilation becomes important. One of these scenarios is the MSSM with soft supersymmetry-breaking squark and slepton masses that are universal at an input GUT renormalization scale, but with non-universal gaugino masses. The other scenario is an extension of the MSSM to include vector-like supermultiplets. In both scenarios, we identify the regions of parameter space where gluino coannihilation is important, and discuss their relations to other regions of parametermore » space where other mechanisms bring the dark matter density into the range allowed by cosmology. In the case of the non-universal MSSM scenario, we find that the allowed range of parameter space is constrained by the requirement of electroweak symmetry breaking, the avoidance of a charged LSP and the measured mass of the Higgs boson, in particular, as well as the appearance of other dark matter (co)annihilation processes. Nevertheless, LSP masses m X ≲ 8TeV with the correct dark matter density are quite possible. In the case of pure gravity mediation with additional vector-like supermultiplets, changes to the anomaly-mediated gluino mass and the threshold effects associated with these states can make the gluino almost degenerate with the LSP, and we find a similar upper bound.« less

Percolative theories of strongly disordered ceramic high-temperature superconductors.

PubMed

Phillips, J C

2010-01-26

Optimally doped ceramic superconductors (cuprates, pnictides, etc.) exhibit transition temperatures T(c) much larger than strongly coupled metallic superconductors like Pb (T(c) = 7.2 K, E(g)/kT(c) = 4.5) and exhibit many universal features that appear to contradict the Bardeen, Cooper, and Schrieffer theory of superconductivity based on attractive electron-phonon pairing interactions. These complex materials are strongly disordered and contain several competing nanophases that cannot be described effectively by parameterized Hamiltonian models, yet their phase diagrams also exhibit many universal features in both the normal and superconductive states. Here we review the rapidly growing body of experimental results that suggest that these anomalously universal features are the result of marginal stabilities of the ceramic electronic and lattice structures. These dual marginal stabilities favor both electronic percolation of a dopant network and rigidity percolation of the deformed lattice network. This "double percolation" model has previously explained many features of the normal-state transport properties of these materials and is the only theory that has successfully predicted strict lowest upper bounds for T(c) in the cuprate and pnictide families. Here it is extended to include Coulomb correlations and percolative band narrowing, as well as an angular energy gap equation, which rationalizes angularly averaged gap/T(c) ratios, and shows that these are similar to those of conventional strongly coupled superconductors.

Vertical structure of tropospheric winds on gas giants

NASA Astrophysics Data System (ADS)

Scott, R. K.; Dunkerton, T. J.

2017-04-01

Zonal mean zonal velocity profiles from cloud-tracking observations on Jupiter and Saturn are used to infer latitudinal variations of potential temperature consistent with a shear stable potential vorticity distribution. Immediately below the cloud tops, density stratification is weaker on the poleward and stronger on the equatorward flanks of midlatitude jets, while at greater depth the opposite relation holds. Thermal wind balance then yields the associated vertical shears of midlatitude jets in an altitude range bounded above by the cloud tops and bounded below by the level where the latitudinal gradient of static stability changes sign. The inferred vertical shear below the cloud tops is consistent with existing thermal profiling of the upper troposphere. The sense of the associated mean meridional circulation in the upper troposphere is discussed, and expected magnitudes are given based on existing estimates of the radiative timescale on each planet.

Gravitating Q-balls in the Affleck-Dine mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tamaki, Takashi; Sakai, Nobuyuki; Department of Education, Yamagata University, Yamagata 990-8560

2011-04-15

We investigate how gravity affects ''Q-balls'' with the Affleck-Dine potential V{sub AD}({phi}):=(m{sup 2}/2){phi}{sup 2} [1+Kln(({phi}/M)){sup 2}]. Contrary to the flat case, in which equilibrium solutions exist only if K<0, we find three types of gravitating solutions as follows. In the case that K<0, ordinary Q-ball solutions exist; there is an upper bound of the charge due to gravity. In the case that K=0, equilibrium solutions called (mini-)boson stars appear due to gravity; there is an upper bound of the charge, too. In the case that K>0, equilibrium solutions appear, too. In this case, these solutions are not asymptotically flat butmore » surrounded by Q-matter. These solutions might be important in considering a dark matter scenario in the Affleck-Dine mechanism.« less

Precision Measurement of the Electron's Electric Dipole Moment Using Trapped Molecular Ions.

PubMed

Cairncross, William B; Gresh, Daniel N; Grau, Matt; Cossel, Kevin C; Roussy, Tanya S; Ni, Yiqi; Zhou, Yan; Ye, Jun; Cornell, Eric A

2017-10-13

We describe the first precision measurement of the electron's electric dipole moment (d_{e}) using trapped molecular ions, demonstrating the application of spin interrogation times over 700 ms to achieve high sensitivity and stringent rejection of systematic errors. Through electron spin resonance spectroscopy on ^{180}Hf^{19}F^{+} in its metastable ^{3}Δ_{1} electronic state, we obtain d_{e}=(0.9±7.7_{stat}±1.7_{syst})×10^{-29}  e cm, resulting in an upper bound of |d_{e}|<1.3×10^{-28}  e cm (90% confidence). Our result provides independent confirmation of the current upper bound of |d_{e}|<9.4×10^{-29}  e cm [J. Baron et al., New J. Phys. 19, 073029 (2017)NJOPFM1367-263010.1088/1367-2630/aa708e], and offers the potential to improve on this limit in the near future.

Insights into the Earth System mass variability from CSR-RL05 GRACE gravity fields

NASA Astrophysics Data System (ADS)

Bettadpur, S.

2012-04-01

The next-generation Release-05 GRACE gravity field data products are the result of extensive effort applied to the improvements to the GRACE Level-1 (tracking) data products, and to improvements in the background gravity models and processing methodology. As a result, the squared-error upper-bound in RL05 fields is half or less than the squared-error upper-bound in RL04 fields. The CSR-RL05 field release consists of unconstrained gravity fields as well as a regularized gravity field time-series that can be used for several applications without any post-processing error reduction. This paper will describe the background and the nature of these improvements in the data products, and provide an error characterization. We will describe the insights these new series offer in measuring the mass flux due to diverse Hydrologic, Oceanographic and Cryospheric processes.

Potential-field sounding using Euler's homogeneity equation and Zidarov bubbling

USGS Publications Warehouse

Cordell, Lindrith

1994-01-01

Potential-field (gravity) data are transformed into a physical-property (density) distribution in a lower half-space, constrained solely by assumed upper bounds on physical-property contrast and data error. A two-step process is involved. The data are first transformed to an equivalent set of line (2-D case) or point (3-D case) sources, using Euler's homogeneity equation evaluated iteratively on the largest residual data value. Then, mass is converted to a volume-density product, constrained to an upper density bound, by 'bubbling,' which exploits circular or radial expansion to redistribute density without changing the associated gravity field. The method can be developed for gravity or magnetic data in two or three dimensions. The results can provide a beginning for interpretation of potential-field data where few independent constraints exist, or more likely, can be used to develop models and confirm or extend interpretation of other geophysical data sets.

Search for violations of quantum mechanics

DOE PAGES

Ellis, John; Hagelin, John S.; Nanopoulos, D. V.; ...

1984-07-01

The treatment of quantum effects in gravitational fields indicates that pure states may evolve into mixed states, and Hawking has proposed modification of the axioms of field theory which incorporate the corresponding violation of quantum mechanics. In this study we propose a modified hamiltonian equation of motion for density matrices and use it to interpret upper bounds on the violation of quantum mechanics in different phenomenological situations. We apply our formalism to the K 0-K 0 system and to long baseline neutron interferometry experiments. In both cases we find upper bounds of about 2 × 10 -21 GeV on contributionsmore » to the single particle “hamiltonian” which violate quantum mechanical coherence. We discuss how these limits might be improved in the future, and consider the relative significance of other successful tests of quantum mechanics. Finally, an appendix contains model estimates of the magnitude of effects violating quantum mechanics.« less

An Analytical Framework for Runtime of a Class of Continuous Evolutionary Algorithms.

PubMed

Zhang, Yushan; Hu, Guiwu

2015-01-01

Although there have been many studies on the runtime of evolutionary algorithms in discrete optimization, relatively few theoretical results have been proposed on continuous optimization, such as evolutionary programming (EP). This paper proposes an analysis of the runtime of two EP algorithms based on Gaussian and Cauchy mutations, using an absorbing Markov chain. Given a constant variation, we calculate the runtime upper bound of special Gaussian mutation EP and Cauchy mutation EP. Our analysis reveals that the upper bounds are impacted by individual number, problem dimension number n, searching range, and the Lebesgue measure of the optimal neighborhood. Furthermore, we provide conditions whereby the average runtime of the considered EP can be no more than a polynomial of n. The condition is that the Lebesgue measure of the optimal neighborhood is larger than a combinatorial calculation of an exponential and the given polynomial of n.

Estimation of the lower and upper bounds on the probability of failure using subset simulation and random set theory

NASA Astrophysics Data System (ADS)

Alvarez, Diego A.; Uribe, Felipe; Hurtado, Jorge E.

2018-02-01

Random set theory is a general framework which comprises uncertainty in the form of probability boxes, possibility distributions, cumulative distribution functions, Dempster-Shafer structures or intervals; in addition, the dependence between the input variables can be expressed using copulas. In this paper, the lower and upper bounds on the probability of failure are calculated by means of random set theory. In order to accelerate the calculation, a well-known and efficient probability-based reliability method known as subset simulation is employed. This method is especially useful for finding small failure probabilities in both low- and high-dimensional spaces, disjoint failure domains and nonlinear limit state functions. The proposed methodology represents a drastic reduction of the computational labor implied by plain Monte Carlo simulation for problems defined with a mixture of representations for the input variables, while delivering similar results. Numerical examples illustrate the efficiency of the proposed approach.

Crustal volumes of the continents and of oceanic and continental submarine plateaus

NASA Technical Reports Server (NTRS)

Schubert, G.; Sandwell, D.

1989-01-01

Using global topographic data and the assumption of Airy isostasy, it is estimated that the crustal volume of the continents is 7182 X 10 to the 6th cu km. The crustal volumes of the oceanic and continental submarine plateaus are calculated at 369 X 10 to the 6th cu km and 242 X 10 to the 6th cu km, respectively. The total continental crustal volume is found to be 7581 X 10 to the 6th cu km, 3.2 percent of which is comprised of continental submarine plateaus on the seafloor. An upper bound on the contintental crust addition rate by the accretion of oceanic plateaus is set at 3.7 cu km/yr. Subduction of continental submarine plateaus with the oceanic lithosphere on a 100 Myr time scale yields an upper bound to the continental crustal subtraction rate of 2.4 cu km/yr.

Comparison of various techniques for calibration of AIS data

NASA Technical Reports Server (NTRS)

Roberts, D. A.; Yamaguchi, Y.; Lyon, R. J. P.

1986-01-01

The Airborne Imaging Spectrometer (AIS) samples a region which is strongly influenced by decreasing solar irradiance at longer wavelengths and strong atmospheric absorptions. Four techniques, the Log Residual, the Least Upper Bound Residual, the Flat Field Correction and calibration using field reflectance measurements were investigated as a means for removing these two features. Of the four techniques field reflectance calibration proved to be superior in terms of noise and normalization. Of the other three techniques, the Log Residual was superior when applied to areas which did not contain one dominant cover type. In heavily vegetated areas, the Log Residual proved to be ineffective. After removing anomalously bright data values, the Least Upper Bound Residual proved to be almost as effective as the Log Residual in sparsely vegetated areas and much more effective in heavily vegetated areas. Of all the techniques, the Flat Field Correction was the noisest.

Isotope-abundance variations and atomic weights of selected elements: 2016 (IUPAC Technical Report)

USGS Publications Warehouse

Coplen, Tyler B.; Shrestha, Yesha

2016-01-01

There are 63 chemical elements that have two or more isotopes that are used to determine their standard atomic weights. The isotopic abundances and atomic weights of these elements can vary in normal materials due to physical and chemical fractionation processes (not due to radioactive decay). These variations are well known for 12 elements (hydrogen, lithium, boron, carbon, nitrogen, oxygen, magnesium, silicon, sulfur, chlorine, bromine, and thallium), and the standard atomic weight of each of these elements is given by IUPAC as an interval with lower and upper bounds. Graphical plots of selected materials and compounds of each of these elements have been published previously. Herein and at the URL http://dx.doi.org/10.5066/F7GF0RN2, we provide isotopic abundances, isotope-delta values, and atomic weights for each of the upper and lower bounds of these materials and compounds.

Constructions for finite-state codes

NASA Technical Reports Server (NTRS)

Pollara, F.; Mceliece, R. J.; Abdel-Ghaffar, K.

1987-01-01

A class of codes called finite-state (FS) codes is defined and investigated. These codes, which generalize both block and convolutional codes, are defined by their encoders, which are finite-state machines with parallel inputs and outputs. A family of upper bounds on the free distance of a given FS code is derived from known upper bounds on the minimum distance of block codes. A general construction for FS codes is then given, based on the idea of partitioning a given linear block into cosets of one of its subcodes, and it is shown that in many cases the FS codes constructed in this way have a d sub free which is as large as possible. These codes are found without the need for lengthy computer searches, and have potential applications for future deep-space coding systems. The issue of catastropic error propagation (CEP) for FS codes is also investigated.

An upper-bound assessment of the benefits of reducing perchlorate in drinking water.

PubMed

Lutter, Randall

2014-10-01

The Environmental Protection Agency plans to issue new federal regulations to limit drinking water concentrations of perchlorate, which occurs naturally and results from the combustion of rocket fuel. This article presents an upper-bound estimate of the potential benefits of alternative maximum contaminant levels for perchlorate in drinking water. The results suggest that the economic benefits of reducing perchlorate concentrations in drinking water are likely to be low, i.e., under $2.9 million per year nationally, for several reasons. First, the prevalence of detectable perchlorate in public drinking water systems is low. Second, the population especially sensitive to effects of perchlorate, pregnant women who are moderately iodide deficient, represents a minority of all pregnant women. Third, and perhaps most importantly, reducing exposure to perchlorate in drinking water is a relatively ineffective way of increasing iodide uptake, a crucial step linking perchlorate to health effects of concern. © 2014 Society for Risk Analysis.

Fault-tolerant clock synchronization validation methodology. [in computer systems

NASA Technical Reports Server (NTRS)

Butler, Ricky W.; Palumbo, Daniel L.; Johnson, Sally C.

1987-01-01

A validation method for the synchronization subsystem of a fault-tolerant computer system is presented. The high reliability requirement of flight-crucial systems precludes the use of most traditional validation methods. The method presented utilizes formal design proof to uncover design and coding errors and experimentation to validate the assumptions of the design proof. The experimental method is described and illustrated by validating the clock synchronization system of the Software Implemented Fault Tolerance computer. The design proof of the algorithm includes a theorem that defines the maximum skew between any two nonfaulty clocks in the system in terms of specific system parameters. Most of these parameters are deterministic. One crucial parameter is the upper bound on the clock read error, which is stochastic. The probability that this upper bound is exceeded is calculated from data obtained by the measurement of system parameters. This probability is then included in a detailed reliability analysis of the system.

Achieving unequal error protection with convolutional codes

NASA Technical Reports Server (NTRS)

Mills, D. G.; Costello, D. J., Jr.; Palazzo, R., Jr.

1994-01-01

This paper examines the unequal error protection capabilities of convolutional codes. Both time-invariant and periodically time-varying convolutional encoders are examined. The effective free distance vector is defined and is shown to be useful in determining the unequal error protection (UEP) capabilities of convolutional codes. A modified transfer function is used to determine an upper bound on the bit error probabilities for individual input bit positions in a convolutional encoder. The bound is heavily dependent on the individual effective free distance of the input bit position. A bound relating two individual effective free distances is presented. The bound is a useful tool in determining the maximum possible disparity in individual effective free distances of encoders of specified rate and memory distribution. The unequal error protection capabilities of convolutional encoders of several rates and memory distributions are determined and discussed.

Gauge mediation at the LHC: status and prospects

DOE PAGES

Knapen, Simon; Redigolo, Diego

2017-01-30

We show that the predictivity of general gauge mediation (GGM) with TeV-scale stops is greatly increased once the Higgs mass constraint is imposed. The most notable results are a strong lower bound on the mass of the gluino and right-handed squarks, and an upper bound on the Higgsino mass. If the μ-parameter is positive, the wino mass is also bounded from above. These constraints relax significantly for high messenger scales and as such long-lived NLSPs are favored in GGM. We identify a small set of most promising topologies for the neutralino/sneutrino NLSP scenarios and estimate the impact of the currentmore » bounds and the sensitivity of the high luminosity LHC. The stau, stop and sbottom NLSP scenarios can be robustly excluded at the high luminosity LHC.« less

On the Inequalities of Babu\\vska-Aziz, Friedrichs and Horgan-Payne

NASA Astrophysics Data System (ADS)

Costabel, Martin; Dauge, Monique

2015-09-01

The equivalence between the inequalities of Babu\\vska-Aziz and Friedrichs for sufficiently smooth bounded domains in the plane was shown by Horgan and Payne 30 years ago. We prove that this equivalence, and the equality between the associated constants, is true without any regularity condition on the domain. For the Horgan-Payne inequality, which is an upper bound of the Friedrichs constant for plane star-shaped domains in terms of a geometric quantity known as the Horgan-Payne angle, we show that it is true for some classes of domains, but not for all bounded star-shaped domains. We prove a weaker inequality that is true in all cases.

A simple method for assessing occupational exposure via the one-way random effects model.

PubMed

Krishnamoorthy, K; Mathew, Thomas; Peng, Jie

2016-11-01

A one-way random effects model is postulated for the log-transformed shift-long personal exposure measurements, where the random effect in the model represents an effect due to the worker. Simple closed-form confidence intervals are proposed for the relevant parameters of interest using the method of variance estimates recovery (MOVER). The performance of the confidence bounds is evaluated and compared with those based on the generalized confidence interval approach. Comparison studies indicate that the proposed MOVER confidence bounds are better than the generalized confidence bounds for the overall mean exposure and an upper percentile of the exposure distribution. The proposed methods are illustrated using a few examples involving industrial hygiene data.

Wave height estimates from pressure and velocity data at an intermediate depth in the presence of uniform currents

NASA Astrophysics Data System (ADS)

Basu, Biswajit

2017-12-01

Bounds on estimates of wave heights (valid for large amplitudes) from pressure and flow measurements at an arbitrary intermediate depth have been provided. Two-dimensional irrotational steady water waves over a flat bed with a finite depth in the presence of underlying uniform currents have been considered in the analysis. Five different upper bounds based on a combination of pressure and velocity field measurements have been derived, though there is only one available lower bound on the wave height in the case of the speed of current greater than or less than the wave speed. This article is part of the theme issue 'Nonlinear water waves'.

A communication channel model of the software process

NASA Technical Reports Server (NTRS)

Tausworthe, R. C.

1988-01-01

Reported here is beginning research into a noisy communication channel analogy of software development process productivity, in order to establish quantifiable behavior and theoretical bounds. The analogy leads to a fundamental mathematical relationship between human productivity and the amount of information supplied by the developers, the capacity of the human channel for processing and transmitting information, the software product yield (object size), the work effort, requirements efficiency, tool and process efficiency, and programming environment advantage. Also derived is an upper bound to productivity that shows that software reuse is the only means than can lead to unbounded productivity growth; practical considerations of size and cost of reusable components may reduce this to a finite bound.

A communication channel model of the software process

NASA Technical Reports Server (NTRS)

Tausworthe, Robert C.

1988-01-01

Beginning research into a noisy communication channel analogy of software development process productivity, in order to establish quantifiable behavior and theoretical bounds is discussed. The analogy leads to a fundamental mathematical relationship between human productivity and the amount of information supplied by the developers, the capacity of the human channel for processing and transmitting information, the software product yield (object size) the work effort, requirements efficiency, tool and process efficiency, and programming environment advantage. An upper bound to productivity is derived that shows that software reuse is the only means that can lead to unbounded productivity growth; practical considerations of size and cost of reusable components may reduce this to a finite bound.

A passivity criterion for sampled-data bilateral teleoperation systems.

PubMed

Jazayeri, Ali; Tavakoli, Mahdi

2013-01-01

A teleoperation system consists of a teleoperator, a human operator, and a remote environment. Conditions involving system and controller parameters that ensure the teleoperator passivity can serve as control design guidelines to attain maximum teleoperation transparency while maintaining system stability. In this paper, sufficient conditions for teleoperator passivity are derived for when position error-based controllers are implemented in discrete-time. This new analysis is necessary because discretization causes energy leaks and does not necessarily preserve the passivity of the system. The proposed criterion for sampled-data teleoperator passivity imposes lower bounds on the teleoperator's robots dampings, an upper bound on the sampling time, and bounds on the control gains. The criterion is verified through simulations and experiments.

Reliability Estimating Procedures for Electric and Thermochemical Propulsion Systems. Volume 1

DTIC Science & Technology

1977-02-01

Laboratories, The Marquardt Company, NASA Goddard Space Flight Center, RCA Astro Elec- tronics, Rockwell International, Applied Physics Laboratory...E fX ) 2.3 Failure Rate Means and Bounds 5% Lower Bound Median Mean 95% Upper Bound A.05 X.05 . AIA. 9 5 0.00025 0.0024 0.06 0.022 x10- 6 per cycle, 1...Iq IIt. Xg4 4l Wl ~ 4𔃺 L Q ൘ I1-269 I- I J N1- 74-i Liu I- (~J~~~jto 1-27 r4J > U 0 1-271 T 27 fX ~𔃽 0L 1-273 -- va VAv( 13 1-272 %J% ~ii 000 41

Robust Bounded Influence Tests in Linear Models

DTIC Science & Technology

1988-11-01

sensitivity analysis and bounded influence estimation. In: Evaluation of Econometric Models, J. Kmenta and J.B. Ramsey (eds.) Academic Press, New York...1R’OBUST bOUNDED INFLUENCE TESTS IN LINEA’ MODELS and( I’homas P. [lettmansperger* Tim [PennsylvanLa State UJniversity A M i0d fix pu111 rsos.p JJ 1 0...November 1988 ROBUST BOUNDED INFLUENCE TESTS IN LINEAR MODELS Marianthi Markatou The University of Iowa and Thomas P. Hettmansperger* The Pennsylvania

Ada (Trade Name)/SQL (Structured Query Language) Binding Specification

DTIC Science & Technology

1988-06-01

TYPES iS package ADA-SOL Is type DWPLOYEEyNAME Is new STRING ( 1 .. 30 ); type BOSSNAME is new EMPLOYEENAME; type EMPLOYEE SALARY is digits 7 range 0.00...minimum number of significant decimal digits . All real numbers between the lower and upper bounds, inclusive, belong to the subtype, and are...and the elements of strings. Format <character> -:- < digit > I <letter> ! <special character> < digit > ::- 0111213141516171819 <letter> ::- <upper case

Characterization of Seismic Noise at Selected Non-Urban Sites

DTIC Science & Technology

2010-03-01

Field sites for seismic recordings: Scottish moor (upper left), Enfield, NH (upper right), and vicinity of Keele, England (bottom). ERDC...three sites. The sites are: a wind farm on a remote moor in Scotland, a ~13 acre field bounded by woods in a rural Enfield, NH neigh- borhood, and a site...in a rural Enfield, NH, neighborhood, and a site transitional from developed land to farmland within 1 km of the six-lane M6 motorway near Keele

Estimation of inflation parameters for Perturbed Power Law model using recent CMB measurements

NASA Astrophysics Data System (ADS)

Mukherjee, Suvodip; Das, Santanu; Joy, Minu; Souradeep, Tarun

2015-01-01

Cosmic Microwave Background (CMB) is an important probe for understanding the inflationary era of the Universe. We consider the Perturbed Power Law (PPL) model of inflation which is a soft deviation from Power Law (PL) inflationary model. This model captures the effect of higher order derivative of Hubble parameter during inflation, which in turn leads to a non-zero effective mass meff for the inflaton field. The higher order derivatives of Hubble parameter at leading order sources constant difference in the spectral index for scalar and tensor perturbation going beyond PL model of inflation. PPL model have two observable independent parameters, namely spectral index for tensor perturbation νt and change in spectral index for scalar perturbation νst to explain the observed features in the scalar and tensor power spectrum of perturbation. From the recent measurements of CMB power spectra by WMAP, Planck and BICEP-2 for temperature and polarization, we estimate the feasibility of PPL model with standard ΛCDM model. Although BICEP-2 claimed a detection of r=0.2, estimates of dust contamination provided by Planck have left open the possibility that only upper bound on r will be expected in a joint analysis. As a result we consider different upper bounds on the value of r and show that PPL model can explain a lower value of tensor to scalar ratio (r<0.1 or r<0.01) for a scalar spectral index of ns=0.96 by having a non-zero value of effective mass of the inflaton field m2eff/H2. The analysis with WP + Planck likelihood shows a non-zero detection of m2eff/H2 with 5.7 σ and 8.1 σ respectively for r<0.1 and r<0.01. Whereas, with BICEP-2 likelihood m2eff/H2 = -0.0237 ± 0.0135 which is consistent with zero.

Exploring CP violation in the MSSM.

PubMed

Arbey, Alexandre; Ellis, John; Godbole, Rohini M; Mahmoudi, Farvah

We explore the prospects for observing CP violation in the minimal supersymmetric extension of the Standard Model (MSSM) with six CP-violating parameters, three gaugino mass phases and three phases in trilinear soft supersymmetry-breaking parameters, using the CPsuperH code combined with a geometric approach to maximise CP-violating observables subject to the experimental upper bounds on electric dipole moments. We also implement CP-conserving constraints from Higgs physics, flavour physics and the upper limits on the cosmological dark matter density and spin-independent scattering. We study possible values of observables within the constrained MSSM (CMSSM), the non-universal Higgs model (NUHM), the CPX scenario and a variant of the phenomenological MSSM (pMSSM). We find values of the CP-violating asymmetry [Formula: see text] in [Formula: see text] decay that may be as large as 3 %, so future measurements of [Formula: see text] may provide independent information about CP violation in the MSSM. We find that CP-violating MSSM contributions to the [Formula: see text] meson mass mixing term [Formula: see text] are in general below the present upper limit, which is dominated by theoretical uncertainties. If these could be reduced, [Formula: see text] could also provide an interesting and complementary constraint on the six CP-violating MSSM phases, enabling them all to be determined experimentally, in principle. We also find that CP violation in the [Formula: see text] and [Formula: see text] couplings can be quite large, and so may offer interesting prospects for future [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] colliders.

2. 1827 Landscape Plan Jefferson's Academical Village, Bounded by ...

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

2. 1827 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

14. 2013 Landscape Plan Jefferson's Academical Village, Bounded by ...

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

14. 2013 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

5. 1880 Landscape Plan Jefferson's Academical Village, Bounded by ...

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

5. 1880 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

11. 1981 Landscape Plan Jefferson's Academical Village, Bounded by ...

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

11. 1981 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

7. 1914 Landscape Plan Jefferson's Academical Village, Bounded by ...

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

7. 1914 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

9. 1947 Landscape Plan Jefferson's Academical Village, Bounded by ...

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

9. 1947 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

3. 1860 Landscape Plan Jefferson's Academical Village, Bounded by ...

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

3. 1860 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

8. 1914 Tree Plan Jefferson's Academical Village, Bounded by ...

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

8. 1914 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

6. 1880 Tree Plan Jefferson's Academical Village, Bounded by ...

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

6. 1880 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

4. 1860 Tree Plan Jefferson's Academical Village, Bounded by ...

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

4. 1860 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

10. 1947 Tree Plan Jefferson's Academical Village, Bounded by ...

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

10. 1947 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

12. 1981 Tree Plan Jefferson's Academical Village, Bounded by ...

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

12. 1981 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

Universality of the Volume Bound in Slow-Roll Eternal Inflation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dubovsky, Sergei; Senatore, Leonardo; Villadoro, Giovanni

2012-03-28

It has recently been shown that in single field slow-roll inflation the total volume cannot grow by a factor larger than e{sup S{sub dS}/2} without becoming infinite. The bound is saturated exactly at the phase transition to eternal inflation where the probability to produce infinite volume becomes non zero. We show that the bound holds sharply also in any space-time dimensions, when arbitrary higher-dimensional operators are included and in the multi-field inflationary case. The relation with the entropy of de Sitter and the universality of the bound strengthen the case for a deeper holographic interpretation. As a spin-off we providemore » the formalism to compute the probability distribution of the volume after inflation for generic multi-field models, which might help to address questions about the population of vacua of the landscape during slow-roll inflation.« less

Length estimations of presumed upward connecting leaders in lightning flashes to flat water and flat ground

NASA Astrophysics Data System (ADS)

Stolzenburg, Maribeth; Marshall, Thomas C.; Karunarathne, Sumedhe; Orville, Richard E.

2018-10-01

Using video data recorded at 50,000 frames per second for nearby negative lightning flashes, estimates are derived for the length of positive upward connecting leaders (UCLs) that presumably formed prior to new ground attachments. Return strokes were 1.7 to 7.8 km distant, yielding image resolutions of 4.25 to 19.5 m. No UCLs are imaged in these data, indicating those features were too transient or too dim compared to other lightning processes that are imaged at these resolutions. Upper bound lengths for 17 presumed UCLs are determined from the height above flat ground or water of the successful stepped leader tip in the image immediately prior to (within 20 μs before) the return stroke. Better estimates of maximum UCL lengths are determined using the downward stepped leader tip's speed of advance and the estimated return stroke time within its first frame. For 17 strokes, the upper bound length of the possible UCL averages 31.6 m and ranges from 11.3 to 50.3 m. Among the close strokes (those with spatial resolution <8 m per pixel), the five which connected to water (salt water lagoon) have UCL upper bound estimates averaging significantly shorter (24.1 m) than the average for the three close strokes which connected to land (36.9 m). The better estimates of maximum UCL lengths for the eight close strokes average 20.2 m, with slightly shorter average of 18.3 m for the five that connected to water. All the better estimates of UCL maximum lengths are <38 m in this dataset

Modification of the activity of cell wall-bound peroxidase by hypergravity in relation to the stimulation of lignin formation in azuki bean epicotyls

NASA Astrophysics Data System (ADS)

Wakabayashi, Kazuyuki; Nakano, Saho; Soga, Kouichi; Hoson, Takayuki

Lignin is a component of cell walls of terrestrial plants, which provides cell walls with the mechanical rigidity. Lignin is a phenolic polymer with high molecular mass and formed by the polymerization of phenolic substances on a cellulosic matrix. The polymerization is catalyzed by cell wall-bound peroxidase, and thus the activity of this enzyme regulates the rate of formation of lignin. In the present study, the changes in the lignin content and the activity of cell wall peroxidase were investigated along epicotyls of azuki bean seedlings grown under hypergravity conditions. The endogenous growth occurred primarily in the upper regions of the epicotyl and no growth was detected in the middle or basal regions. The amounts of acetyl bromide-soluble lignin increased from the upper to the basal regions of epicotyls. The lignin content per unit length in the basal region was three times higher than that in the upper region. Hypergravity treatment at 300 g for 6 h stimulated the increase in the lignin content in all regions of epicotyls, particularly in the basal regions. The peroxidase activity in the protein fraction extracted from the cell wall preparation with a high ionic strength buffer also increased gradually toward the basal region, and hypergravity treatment clearly increased the activity in all regions. There was a close correlation between the lignin content and the enzyme activity. These results suggest that gravity stimuli modulate the activity of cell wall-bound peroxidase, which, in turn, causes the stimulation of the lignin formation in stem organs.

Thermalization Time Bounds for Pauli Stabilizer Hamiltonians

NASA Astrophysics Data System (ADS)

Temme, Kristan

2017-03-01

We prove a general lower bound to the spectral gap of the Davies generator for Hamiltonians that can be written as the sum of commuting Pauli operators. These Hamiltonians, defined on the Hilbert space of N-qubits, serve as one of the most frequently considered candidates for a self-correcting quantum memory. A spectral gap bound on the Davies generator establishes an upper limit on the life time of such a quantum memory and can be used to estimate the time until the system relaxes to thermal equilibrium when brought into contact with a thermal heat bath. The bound can be shown to behave as {λ ≥ O(N^{-1} exp(-2β overline{ɛ}))}, where {overline{ɛ}} is a generalization of the well known energy barrier for logical operators. Particularly in the low temperature regime we expect this bound to provide the correct asymptotic scaling of the gap with the system size up to a factor of N -1. Furthermore, we discuss conditions and provide scenarios where this factor can be removed and a constant lower bound can be proven.

A duality approach for solving bounded linear programming problems with fuzzy variables based on ranking functions and its application in bounded transportation problems

NASA Astrophysics Data System (ADS)

Ebrahimnejad, Ali

2015-08-01

There are several methods, in the literature, for solving fuzzy variable linear programming problems (fuzzy linear programming in which the right-hand-side vectors and decision variables are represented by trapezoidal fuzzy numbers). In this paper, the shortcomings of some existing methods are pointed out and to overcome these shortcomings a new method based on the bounded dual simplex method is proposed to determine the fuzzy optimal solution of that kind of fuzzy variable linear programming problems in which some or all variables are restricted to lie within lower and upper bounds. To illustrate the proposed method, an application example is solved and the obtained results are given. The advantages of the proposed method over existing methods are discussed. Also, one application of this algorithm in solving bounded transportation problems with fuzzy supplies and demands is dealt with. The proposed method is easy to understand and to apply for determining the fuzzy optimal solution of bounded fuzzy variable linear programming problems occurring in real-life situations.

Stability of Nonlinear Systems with Unknown Time-varying Feedback Delay

NASA Astrophysics Data System (ADS)

Chunodkar, Apurva A.; Akella, Maruthi R.

2013-12-01

This paper considers the problem of stabilizing a class of nonlinear systems with unknown bounded delayed feedback wherein the time-varying delay is 1) piecewise constant 2) continuous with a bounded rate. We also consider application of these results to the stabilization of rigid-body attitude dynamics. In the first case, the time-delay in feedback is modeled specifically as a switch among an arbitrarily large set of unknown constant values with a known strict upper bound. The feedback is a linear function of the delayed states. In the case of linear systems with switched delay feedback, a new sufficiency condition for average dwell time result is presented using a complete type Lyapunov-Krasovskii (L-K) functional approach. Further, the corresponding switched system with nonlinear perturbations is proven to be exponentially stable inside a well characterized region of attraction for an appropriately chosen average dwell time. In the second case, the concept of the complete type L-K functional is extended to a class of nonlinear time-delay systems with unknown time-varying time-delay. This extension ensures stability robustness to time-delay in the control design for all values of time-delay less than the known upper bound. Model-transformation is used in order to partition the nonlinear system into a nominal linear part that is exponentially stable with a bounded perturbation. We obtain sufficient conditions which ensure exponential stability inside a region of attraction estimate. A constructive method to evaluate the sufficient conditions is presented together with comparison with the corresponding constant and piecewise constant delay. Numerical simulations are performed to illustrate the theoretical results of this paper.

Chang'e 3 lunar mission and upper limit on stochastic background of gravitational wave around the 0.01 Hz band

NASA Astrophysics Data System (ADS)

Tang, Wenlin; Xu, Peng; Hu, Songjie; Cao, Jianfeng; Dong, Peng; Bu, Yanlong; Chen, Lue; Han, Songtao; Gong, Xuefei; Li, Wenxiao; Ping, Jinsong; Lau, Yun-Kau; Tang, Geshi

2017-09-01

The Doppler tracking data of the Chang'e 3 lunar mission is used to constrain the stochastic background of gravitational wave in cosmology within the 1 mHz to 0.05 Hz frequency band. Our result improves on the upper bound on the energy density of the stochastic background of gravitational wave in the 0.02-0.05 Hz band obtained by the Apollo missions, with the improvement reaching almost one order of magnitude at around 0.05 Hz. Detailed noise analysis of the Doppler tracking data is also presented, with the prospect that these noise sources will be mitigated in future Chinese deep space missions. A feasibility study is also undertaken to understand the scientific capability of the Chang'e 4 mission, due to be launched in 2018, in relation to the stochastic gravitational wave background around 0.01 Hz. The study indicates that the upper bound on the energy density may be further improved by another order of magnitude from the Chang'e 3 mission, which will fill the gap in the frequency band from 0.02 Hz to 0.1 Hz in the foreseeable future.

The generalized truncated exponential distribution as a model for earthquake magnitudes

NASA Astrophysics Data System (ADS)

Raschke, Mathias

2015-04-01

The random distribution of small, medium and large earthquake magnitudes follows an exponential distribution (ED) according to the Gutenberg-Richter relation. But a magnitude distribution is truncated in the range of very large magnitudes because the earthquake energy is finite and the upper tail of the exponential distribution does not fit well observations. Hence the truncated exponential distribution (TED) is frequently applied for the modelling of the magnitude distributions in the seismic hazard and risk analysis. The TED has a weak point: when two TEDs with equal parameters, except the upper bound magnitude, are mixed, then the resulting distribution is not a TED. Inversely, it is also not possible to split a TED of a seismic region into TEDs of subregions with equal parameters, except the upper bound magnitude. This weakness is a principal problem as seismic regions are constructed scientific objects and not natural units. It also applies to alternative distribution models. The presented generalized truncated exponential distribution (GTED) overcomes this weakness. The ED and the TED are special cases of the GTED. Different issues of the statistical inference are also discussed and an example of empirical data is presented in the current contribution.

Fundamental limitations of cavity-assisted atom interferometry

NASA Astrophysics Data System (ADS)

Dovale-Álvarez, M.; Brown, D. D.; Jones, A. W.; Mow-Lowry, C. M.; Miao, H.; Freise, A.

2017-11-01

Atom interferometers employing optical cavities to enhance the beam splitter pulses promise significant advances in science and technology, notably for future gravitational wave detectors. Long cavities, on the scale of hundreds of meters, have been proposed in experiments aiming to observe gravitational waves with frequencies below 1 Hz, where laser interferometers, such as LIGO, have poor sensitivity. Alternatively, short cavities have also been proposed for enhancing the sensitivity of more portable atom interferometers. We explore the fundamental limitations of two-mirror cavities for atomic beam splitting, and establish upper bounds on the temperature of the atomic ensemble as a function of cavity length and three design parameters: the cavity g factor, the bandwidth, and the optical suppression factor of the first and second order spatial modes. A lower bound to the cavity bandwidth is found which avoids elongation of the interaction time and maximizes power enhancement. An upper limit to cavity length is found for symmetric two-mirror cavities, restricting the practicality of long baseline detectors. For shorter cavities, an upper limit on the beam size was derived from the geometrical stability of the cavity. These findings aim to aid the design of current and future cavity-assisted atom interferometers.

Limits on the fluctuating part of y-type distortion monopole from Planck and SPT results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khatri, Rishi; Sunyaev, Rashid, E-mail: khatri@mpa-garching.mpg.de, E-mail: sunyaev@mpa-garching.mpg.de

2015-08-01

We use the published Planck and SPT cluster catalogs [1,2] and recently published y-distortion maps [3] to put strong observational limits on the contribution of the fluctuating part of the y-type distortions to the y-distortion monopole. Our bounds are 5.4× 10{sup −8} < ( y) < 2.2× 10{sup −6}. Our upper bound is a factor of 6.8 stronger than the currently best upper 95% confidence limit from COBE-FIRAS of ( y) <15× 10{sup −6}. In the standard cosmology, large scale structure is the only source of such distortions and our limits therefore constrain the baryonic physics involved in the formation of the large scale structure. Our lower limit, from themore » detected clusters in the Planck and SPT catalogs, also implies that a Pixie-like experiment should detect the y-distortion monopole at >27-σ. The biggest sources of uncertainty in our upper limit are the monopole offsets between different HFI channel maps that we estimate to be <10{sup −6}.« less

Approximation Set of the Interval Set in Pawlak's Space

PubMed Central

Wang, Jin; Wang, Guoyin

2014-01-01

The interval set is a special set, which describes uncertainty of an uncertain concept or set Z with its two crisp boundaries named upper-bound set and lower-bound set. In this paper, the concept of similarity degree between two interval sets is defined at first, and then the similarity degrees between an interval set and its two approximations (i.e., upper approximation set R¯(Z) and lower approximation set R_(Z)) are presented, respectively. The disadvantages of using upper-approximation set R¯(Z) or lower-approximation set R_(Z) as approximation sets of the uncertain set (uncertain concept) Z are analyzed, and a new method for looking for a better approximation set of the interval set Z is proposed. The conclusion that the approximation set R 0.5(Z) is an optimal approximation set of interval set Z is drawn and proved successfully. The change rules of R 0.5(Z) with different binary relations are analyzed in detail. Finally, a kind of crisp approximation set of the interval set Z is constructed. We hope this research work will promote the development of both the interval set model and granular computing theory. PMID:25177721

Uncertainty, imprecision, and the precautionary principle in climate change assessment.

PubMed

Borsuk, M E; Tomassini, L

2005-01-01

Statistical decision theory can provide useful support for climate change decisions made under conditions of uncertainty. However, the probability distributions used to calculate expected costs in decision theory are themselves subject to uncertainty, disagreement, or ambiguity in their specification. This imprecision can be described using sets of probability measures, from which upper and lower bounds on expectations can be calculated. However, many representations, or classes, of probability measures are possible. We describe six of the more useful classes and demonstrate how each may be used to represent climate change uncertainties. When expected costs are specified by bounds, rather than precise values, the conventional decision criterion of minimum expected cost is insufficient to reach a unique decision. Alternative criteria are required, and the criterion of minimum upper expected cost may be desirable because it is consistent with the precautionary principle. Using simple climate and economics models as an example, we determine the carbon dioxide emissions levels that have minimum upper expected cost for each of the selected classes. There can be wide differences in these emissions levels and their associated costs, emphasizing the need for care when selecting an appropriate class.

Finite state projection based bounds to compare chemical master equation models using single-cell data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, Zachary; Neuert, Gregor; Department of Pharmacology, School of Medicine, Vanderbilt University, Nashville, Tennessee 37232

2016-08-21

Emerging techniques now allow for precise quantification of distributions of biological molecules in single cells. These rapidly advancing experimental methods have created a need for more rigorous and efficient modeling tools. Here, we derive new bounds on the likelihood that observations of single-cell, single-molecule responses come from a discrete stochastic model, posed in the form of the chemical master equation. These strict upper and lower bounds are based on a finite state projection approach, and they converge monotonically to the exact likelihood value. These bounds allow one to discriminate rigorously between models and with a minimum level of computational effort.more » In practice, these bounds can be incorporated into stochastic model identification and parameter inference routines, which improve the accuracy and efficiency of endeavors to analyze and predict single-cell behavior. We demonstrate the applicability of our approach using simulated data for three example models as well as for experimental measurements of a time-varying stochastic transcriptional response in yeast.« less

Imaginary-frequency polarizability and van der Waals force constants of two-electron atoms, with rigorous bounds

NASA Technical Reports Server (NTRS)

Glover, R. M.; Weinhold, F.

1977-01-01

Variational functionals of Braunn and Rebane (1972) for the imagery-frequency polarizability (IFP) have been generalized by the method of Gramian inequalities to give rigorous upper and lower bounds, valid even when the true (but unknown) unperturbed wavefunction must be represented by a variational approximation. Using these formulas in conjunction with flexible variational trial functions, tight error bounds are computed for the IFP and the associated two- and three-body van der Waals interaction constants of the ground 1(1S) and metastable 2(1,3S) states of He and Li(+). These bounds generally establish the ground-state properties to within a fraction of a per cent and metastable properties to within a few per cent, permitting a comparative assessment of competing theoretical methods at this level of accuracy. Unlike previous 'error bounds' for these properties, the present results have a completely a priori theoretical character, with no empirical input data.

Uniqueness of First Order Post-Newtonian Collinear Solutions for Three-Body Problem under a Scalar-Tensor Theory

NASA Astrophysics Data System (ADS)

Cao, Wei-Guang; Zhou, Tian-Yi; Xie, Yi

2017-10-01

As a continuing investigation of an earlier work that establishes the collinear solutions to the three-body problem with general masses under a scalar-tensor theory, we study these solutions and prove their uniqueness up to the first order post-Newtonian approximation. With the help of observed bounds on the scalar field in the Solar System, we show that the seventh-order polynomial equation determining the distance ratio among the three masses has either one or three positive roots. However, in the case with three positive roots, it is found that two positive roots break down the slow-motion condition for the post-Newtonian approximation so that only one positive root is physically valid. The resulting uniqueness suggests that the locations of the three masses are very close to their Newtonian positions with post-Newtonian corrections of general relativity and the scalar field. We also prove that, in the framework of the scalar-tensor theory, the angular velocity of the collinear configuration is always less than the Newtonian one when all other parameters are fixed. These results are valid only for three-body systems where upper-bounds on the scalar field are compatible with those of the Solar System. Supported by the National Natural Science Foundation of China under Grant Nos. 11573015 and J1210039, and the Innovation Training Project for Undergraduates of Nanjing University, China

Manipulations of Cartesian Graphs: A First Introduction to Analysis.

ERIC Educational Resources Information Center

Lowenthal, Francis; Vandeputte, Christiane

1989-01-01

Introduces an introductory module for analysis. Describes stock of basic functions and their graphs as part one and three methods as part two: transformations of simple graphs, the sum of stock functions, and upper and lower bounds. (YP)

Budgeted Interactive Learning

DTIC Science & Technology

2017-06-15

the methodology of reducing the online-algorithm-selecting problem as a contextual bandit problem, which is yet another interactive learning...KH2016a] Kuan-Hao Huang and Hsuan-Tien Lin. Linear upper confidence bound algorithm for contextual bandit problem with piled rewards. In Proceedings

Amortized entanglement of a quantum channel and approximately teleportation-simulable channels

NASA Astrophysics Data System (ADS)

Kaur, Eneet; Wilde, Mark M.

2018-01-01

This paper defines the amortized entanglement of a quantum channel as the largest difference in entanglement between the output and the input of the channel, where entanglement is quantified by an arbitrary entanglement measure. We prove that the amortized entanglement of a channel obeys several desirable properties, and we also consider special cases such as the amortized relative entropy of entanglement and the amortized Rains relative entropy. These latter quantities are shown to be single-letter upper bounds on the secret-key-agreement and PPT-assisted quantum capacities of a quantum channel, respectively. Of especial interest is a uniform continuity bound for these latter two special cases of amortized entanglement, in which the deviation between the amortized entanglement of two channels is bounded from above by a simple function of the diamond norm of their difference and the output dimension of the channels. We then define approximately teleportation- and positive-partial-transpose-simulable (PPT-simulable) channels as those that are close in diamond norm to a channel which is either exactly teleportation- or PPT-simulable, respectively. These results then lead to single-letter upper bounds on the secret-key-agreement and PPT-assisted quantum capacities of channels that are approximately teleportation- or PPT-simulable, respectively. Finally, we generalize many of the concepts in the paper to the setting of general resource theories, defining the amortized resourcefulness of a channel and the notion of ν-freely-simulable channels, connecting these concepts in an operational way as well.

Unveiling ν secrets with cosmological data: Neutrino masses and mass hierarchy

NASA Astrophysics Data System (ADS)

Vagnozzi, Sunny; Giusarma, Elena; Mena, Olga; Freese, Katherine; Gerbino, Martina; Ho, Shirley; Lattanzi, Massimiliano

2017-12-01

Using some of the latest cosmological data sets publicly available, we derive the strongest bounds in the literature on the sum of the three active neutrino masses, Mν, within the assumption of a background flat Λ CDM cosmology. In the most conservative scheme, combining Planck cosmic microwave background temperature anisotropies and baryon acoustic oscillations (BAO) data, as well as the up-to-date constraint on the optical depth to reionization (τ ), the tightest 95% confidence level upper bound we find is Mν<0.151 eV . The addition of Planck high-ℓ polarization data, which, however, might still be contaminated by systematics, further tightens the bound to Mν<0.118 eV . A proper model comparison treatment shows that the two aforementioned combinations disfavor the inverted hierarchy at ˜64 % C .L . and ˜71 % C .L . , respectively. In addition, we compare the constraining power of measurements of the full-shape galaxy power spectrum versus the BAO signature, from the BOSS survey. Even though the latest BOSS full-shape measurements cover a larger volume and benefit from smaller error bars compared to previous similar measurements, the analysis method commonly adopted results in their constraining power still being less powerful than that of the extracted BAO signal. Our work uses only cosmological data; imposing the constraint Mν>0.06 eV from oscillations data would raise the quoted upper bounds by O (0.1 σ ) and would not affect our conclusions.

Future trends in computer waste generation in India.

PubMed

Dwivedy, Maheshwar; Mittal, R K

2010-11-01

The objective of this paper is to estimate the future projection of computer waste in India and to subsequently analyze their flow at the end of their useful phase. For this purpose, the study utilizes the logistic model-based approach proposed by Yang and Williams to forecast future trends in computer waste. The model estimates future projection of computer penetration rate utilizing their first lifespan distribution and historical sales data. A bounding analysis on the future carrying capacity was simulated using the three parameter logistic curve. The observed obsolete generation quantities from the extrapolated penetration rates are then used to model the disposal phase. The results of the bounding analysis indicate that in the year 2020, around 41-152 million units of computers will become obsolete. The obsolete computer generation quantities are then used to estimate the End-of-Life outflows by utilizing a time-series multiple lifespan model. Even a conservative estimate of the future recycling capacity of PCs will reach upwards of 30 million units during 2025. Apparently, more than 150 million units could be potentially recycled in the upper bound case. However, considering significant future investment in the e-waste recycling sector from all stakeholders in India, we propose a logistic growth in the recycling rate and estimate the requirement of recycling capacity between 60 and 400 million units for the lower and upper bound case during 2025. Finally, we compare the future obsolete PC generation amount of the US and India. Copyright © 2010 Elsevier Ltd. All rights reserved.

Corium shield

DOEpatents

McDonald, Douglas B.; Buchholz, Carol E.

1994-01-01

A shield for restricting molten corium from flowing into a water sump disposed in a floor of a containment vessel includes upper and lower walls which extend vertically upwardly and downwardly from the floor for laterally bounding the sump. The upper wall includes a plurality of laterally spaced apart flow channels extending horizontally therethrough, with each channel having a bottom disposed coextensively with the floor for channeling water therefrom into the sump. Each channel has a height and a length predeterminedly selected for allowing heat from the molten corium to dissipate through the upper and lower walls as it flows therethrough for solidifying the molten corium therein to prevent accumulation thereof in the sump.

Thermodynamic properties of Kehagias-Sfetsos black hole and KS/CFT correspondence

NASA Astrophysics Data System (ADS)

Pradhan, Parthapratim

2017-11-01

We speculate on various thermodynamic features of the inner horizon ({\\mathcal H}-) and outer horizons ({\\mathcal H}+) of Kehagias-Sfetsos (KS) black hole (BH) in the background of the Hořava-Lifshitz gravity. We compute particularly the area product, area sum, area minus and area division of the BH horizons. We find that they all are not showing universal behavior whereas the product is a universal quantity (PRADHAN P., Phys. Lett. B, 747 (2015) 64). Based on these relations, we derive the area bound of all horizons. From the area bound we derive the entropy bound and irreducible mass bound for all the horizons ({\\mathcal H}+/-) . We also observe that the first law of BH thermodynamics and Smarr-Gibbs-Duhem relations do not hold for this BH. The underlying reason behind this failure is due to the scale invariance of the coupling constant. Moreover, we compute the Cosmic-Censorship-Inequality for this BH which gives the lower bound for the total mass of the spacetime and it is supported by the cosmic cencorship conjecture. Finally, we discuss the KS/CFT correspondence via a thermodynamic procedure.

Observed Volume Fluxes and Mixing in the Dardanelles Strait

DTIC Science & Technology

2013-10-04

et al , 2001; Kara el al ., 2008]. [3] It has been recognized for years that the upper-layer outflow from the Dardanelles Strait to the Aegean Sea...than the interior of the sea and manifests itself as a subsurface flow bounded by the upper layer of the Sea of Mannara. 5007 JAROSZ ET AL ...both ends of the Dardanelles Strait, and assuming a steady state mass budget, Unl’uata et al . [1990] estimated mean annual volume transports in the

Exact one-sided confidence limits for the difference between two correlated proportions.

PubMed

Lloyd, Chris J; Moldovan, Max V

2007-08-15

We construct exact and optimal one-sided upper and lower confidence bounds for the difference between two probabilities based on matched binary pairs using well-established optimality theory of Buehler. Starting with five different approximate lower and upper limits, we adjust them to have coverage probability exactly equal to the desired nominal level and then compare the resulting exact limits by their mean size. Exact limits based on the signed root likelihood ratio statistic are preferred and recommended for practical use.

Search for weakly decaying Λn ‾ and ΛΛ exotic bound states in central Pb-Pb collisions at √{sNN} = 2.76 TeV

NASA Astrophysics Data System (ADS)

Adam, J.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmed, I.; Ahn, S. U.; Aimo, I.; Aiola, S.; Ajaz, M.; Akindinov, A.; Alam, S. N.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Alfaro Molina, R.; Alici, A.; Alkin, A.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Alves Garcia Prado, C.; Andrei, C.; Andronic, A.; Anguelov, V.; Anielski, J.; Antičić, T.; Antinori, F.; Antonioli, P.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Armesto, N.; Arnaldi, R.; Aronsson, T.; Arsene, I. C.; Arslandok, M.; Augustinus, A.; Averbeck, R.; Azmi, M. D.; Bach, M.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Baldisseri, A.; Ball, M.; Baltasar Dos Santos Pedrosa, F.; Baral, R. C.; Barbano, A. M.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartalini, P.; Bartke, J.; Bartsch, E.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Batista Camejo, A.; Batyunya, B.; Batzing, P. C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Bello Martinez, H.; Bellwied, R.; Belmont, R.; Belmont-Moreno, E.; Belyaev, V.; Bencedi, G.; Beole, S.; Berceanu, I.; Bercuci, A.; Berdnikov, Y.; Berenyi, D.; Bertens, R. A.; Berzano, D.; Betev, L.; Bhasin, A.; Bhat, I. R.; Bhati, A. K.; Bhattacharjee, B.; Bhom, J.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Bielčík, J.; Bielčíková, J.; Bilandzic, A.; Biswas, S.; Bjelogrlic, S.; Blanco, F.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Bøggild, H.; Boldizsár, L.; Bombara, M.; Book, J.; Borel, H.; Borissov, A.; Borri, M.; Bossú, F.; Botje, M.; Botta, E.; Böttger, S.; Braun-Munzinger, P.; Bregant, M.; Breitner, T.; Broker, T. A.; Browning, T. A.; Broz, M.; Brucken, E. J.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bufalino, S.; Buncic, P.; Busch, O.; Buthelezi, Z.; Buxton, J. T.; Caffarri, D.; Cai, X.; Caines, H.; Calero Diaz, L.; Caliva, A.; Calvo Villar, E.; Camerini, P.; Carena, F.; Carena, W.; Castillo Castellanos, J.; Castro, A. J.; Casula, E. A. R.; Cavicchioli, C.; Ceballos Sanchez, C.; Cepila, J.; Cerello, P.; Chang, B.; Chapeland, S.; Chartier, M.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chibante Barroso, V.; Chinellato, D. D.; Chochula, P.; Choi, K.; Chojnacki, M.; Choudhury, S.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chung, S. U.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Colamaria, F.; Colella, D.; Collu, A.; Colocci, M.; Conesa Balbastre, G.; Conesa del Valle, Z.; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Corrales Morales, Y.; Cortés Maldonado, I.; Cortese, P.; Cosentino, M. R.; Costa, F.; Crochet, P.; Cruz Albino, R.; Cuautle, E.; Cunqueiro, L.; Dahms, T.; Dainese, A.; Danu, A.; Das, D.; Das, I.; Das, S.; Dash, A.; Dash, S.; De, S.; De Caro, A.; de Cataldo, G.; de Cuveland, J.; De Falco, A.; De Gruttola, D.; De Marco, N.; De Pasquale, S.; Deisting, A.; Deloff, A.; Dénes, E.; D'Erasmo, G.; Di Bari, D.; Di Mauro, A.; Di Nezza, P.; Diaz Corchero, M. A.; Dietel, T.; Dillenseger, P.; Divià, R.; Djuvsland, Ø.; Dobrin, A.; Dobrowolski, T.; Domenicis Gimenez, D.; Dönigus, B.; Dordic, O.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Dupieux, P.; Ehlers, R. J.; Elia, D.; Engel, H.; Erazmus, B.; Erhardt, F.; Eschweiler, D.; Espagnon, B.; Estienne, M.; Esumi, S.; Evans, D.; Evdokimov, S.; Eyyubova, G.; Fabbietti, L.; Fabris, D.; Faivre, J.; Fantoni, A.; Fasel, M.; Feldkamp, L.; Felea, D.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fionda, F. M.; Fiore, E. M.; Fleck, M. G.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Frankenfeld, U.; Fuchs, U.; Furget, C.; Furs, A.; Fusco Girard, M.; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gallio, M.; Gangadharan, D. R.; Ganoti, P.; Gao, C.; Garabatos, C.; Garcia-Solis, E.; Gargiulo, C.; Gasik, P.; Germain, M.; Gheata, A.; Gheata, M.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Giubilato, P.; Gladysz-Dziadus, E.; Glässel, P.; Gomez Ramirez, A.; González-Zamora, P.; Gorbunov, S.; Görlich, L.; Gotovac, S.; Grabski, V.; Graczykowski, L. K.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Grosse-Oetringhaus, J. F.; Grossiord, J.-Y.; Grosso, R.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gulkanyan, H.; Gunji, T.; Gupta, A.; Gupta, R.; Haake, R.; Haaland, Ø.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.; Hanratty, L. D.; Hansen, A.; Harris, J. W.; Hartmann, H.; Harton, A.; Hatzifotiadou, D.; Hayashi, S.; Heckel, S. T.; Heide, M.; Helstrup, H.; Herghelegiu, A.; Herrera Corral, G.; Hess, B. A.; Hetland, K. F.; Hilden, T. E.; Hillemanns, H.; Hippolyte, B.; Hristov, P.; Huang, M.; Humanic, T. J.; Hussain, N.; Hussain, T.; Hutter, D.; Hwang, D. S.; Ilkaev, R.; Ilkiv, I.; Inaba, M.; Ionita, C.; Ippolitov, M.; Irfan, M.; Ivanov, M.; Ivanov, V.; Izucheev, V.; Jachołkowski, A.; Jacobs, P. M.; Jahnke, C.; Jang, H. J.; Janik, M. A.; Jayarathna, P. H. S. Y.; Jena, C.; Jena, S.; Jimenez Bustamante, R. T.; Jones, P. G.; Jung, H.; Jusko, A.; Kalinak, P.; Kalweit, A.; Kamin, J.; Kang, J. H.; Kaplin, V.; Kar, S.; Karasu Uysal, A.; Karavichev, O.; Karavicheva, T.; Karpechev, E.; Kebschull, U.; Keidel, R.; Keijdener, D. L. D.; Keil, M.; Khan, K. H.; Khan, M. M.; Khan, P.; Khan, S. A.; Khanzadeev, A.; Kharlov, Y.; Kileng, B.; Kim, B.; Kim, D. W.; Kim, D. J.; Kim, H.; Kim, J. S.; Kim, M.; Kim, M.; Kim, S.; Kim, T.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Kiss, G.; Klay, J. L.; Klein, C.; Klein, J.; Klein-Bösing, C.; Kluge, A.; Knichel, M. L.; Knospe, A. G.; Kobayashi, T.; Kobdaj, C.; Kofarago, M.; Köhler, M. K.; Kollegger, T.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Kondratyuk, E.; Konevskikh, A.; Kouzinopoulos, C.; Kovalenko, V.; Kowalski, M.; Kox, S.; Koyithatta Meethaleveedu, G.; Kral, J.; Králik, I.; Kravčáková, A.; Krelina, M.; Kretz, M.; Krivda, M.; Krizek, F.; Kryshen, E.; Krzewicki, M.; Kubera, A. M.; Kučera, V.; Kucheriaev, Y.; Kugathasan, T.; Kuhn, C.; Kuijer, P. G.; Kulakov, I.; Kumar, J.; Kumar, L.; Kurashvili, P.; Kurepin, A.; Kurepin, A. B.; Kuryakin, A.; Kushpil, S.; Kweon, M. J.; Kwon, Y.; La Pointe, S. L.; La Rocca, P.; Lagana Fernandes, C.; Lakomov, I.; Langoy, R.; Lara, C.; Lardeux, A.; Lattuca, A.; Laudi, E.; Lea, R.; Leardini, L.; Lee, G. R.; Lee, S.; Legrand, I.; Lehnert, J.; Lemmon, R. C.; Lenti, V.; Leogrande, E.; León Monzón, I.; Leoncino, M.; Lévai, P.; Li, S.; Li, X.; Lien, J.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M. A.; Ljunggren, H. M.; Lodato, D. F.; Loenne, P. I.; Loggins, V. R.; Loginov, V.; Loizides, C.; Lopez, X.; López Torres, E.; Lowe, A.; Lu, X.-G.; Luettig, P.; Lunardon, M.; Luparello, G.; Maevskaya, A.; Mager, M.; Mahajan, S.; Mahmood, S. M.; Maire, A.; Majka, R. D.; Malaev, M.; Maldonado Cervantes, I.; Malinina, L.; Mal'Kevich, D.; Malzacher, P.; Mamonov, A.; Manceau, L.; Manko, V.; Manso, F.; Manzari, V.; Marchisone, M.; Mareš, J.; Margagliotti, G. V.; Margotti, A.; Margutti, J.; Marín, A.; Markert, C.; Marquard, M.; Martashvili, I.; Martin, N. A.; Martin Blanco, J.; Martinengo, P.; Martínez, M. I.; Martínez García, G.; Martinez Pedreira, M.; Martynov, Y.; Mas, A.; Masciocchi, S.; Masera, M.; Masoni, A.; Massacrier, L.; Mastroserio, A.; Matyja, A.; Mayer, C.; Mazer, J.; Mazzoni, M. A.; Mcdonald, D.; Meddi, F.; Menchaca-Rocha, A.; Meninno, E.; Mercado Pérez, J.; Meres, M.; Miake, Y.; Mieskolainen, M. M.; Mikhaylov, K.; Milano, L.; Milosevic, J.; Minervini, L. M.; Mischke, A.; Mishra, A. N.; Miśkowiec, D.; Mitra, J.; Mitu, C. M.; Mohammadi, N.; Mohanty, B.; Molnar, L.; Montaño Zetina, L.; Montes, E.; Morando, M.; Moretto, S.; Morreale, A.; Morsch, A.; Muccifora, V.; Mudnic, E.; Mühlheim, D.; Muhuri, S.; Mukherjee, M.; Müller, H.; Mulligan, J. D.; Munhoz, M. G.; Murray, S.; Musa, L.; Musinsky, J.; Nandi, B. K.; Nania, R.; Nappi, E.; Naru, M. U.; Nattrass, C.; Nayak, K.; Nayak, T. K.; Nazarenko, S.; Nedosekin, A.; Nellen, L.; Ng, F.; Nicassio, M.; Niculescu, M.; Niedziela, J.; Nielsen, B. S.; Nikolaev, S.; Nikulin, S.; Nikulin, V.; Noferini, F.; Nomokonov, P.; Nooren, G.; Norman, J.; Nyanin, A.; Nystrand, J.; Oeschler, H.; Oh, S.; Oh, S. K.; Ohlson, A.; Okatan, A.; Okubo, T.; Olah, L.; Oleniacz, J.; Oliveira Da Silva, A. C.; Oliver, M. H.; Onderwaater, J.; Oppedisano, C.; Ortiz Velasquez, A.; Oskarsson, A.; Otwinowski, J.; Oyama, K.; Ozdemir, M.; Pachmayer, Y.; Pagano, P.; Paić, G.; Pajares, C.; Pal, S. K.; Pan, J.; Pandey, A. K.; Pant, D.; Papikyan, V.; Pappalardo, G. S.; Pareek, P.; Park, W. J.; Parmar, S.; Passfeld, A.; Paticchio, V.; Paul, B.; Pawlak, T.; Peitzmann, T.; Pereira Da Costa, H.; Pereira De Oliveira Filho, E.; Peresunko, D.; Pérez Lara, C. E.; Peskov, V.; Pestov, Y.; Petráček, V.; Petrov, V.; Petrovici, M.; Petta, C.; Piano, S.; Pikna, M.; Pillot, P.; Pinazza, O.; Pinsky, L.; Piyarathna, D. B.; Płoskoń, M.; Planinic, M.; Pluta, J.; Pochybova, S.; Podesta-Lerma, P. L. M.; Poghosyan, M. G.; Polichtchouk, B.; Poljak, N.; Poonsawat, W.; Pop, A.; Porteboeuf-Houssais, S.; Porter, J.; Pospisil, J.; Prasad, S. K.; Preghenella, R.; Prino, F.; Pruneau, C. A.; Pshenichnov, I.; Puccio, M.; Puddu, G.; Pujahari, P.; Punin, V.; Putschke, J.; Qvigstad, H.; Rachevski, A.; Raha, S.; Rajput, S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Raniwala, R.; Raniwala, S.; Räsänen, S. S.; Rascanu, B. T.; Rathee, D.; Razazi, V.; Read, K. F.; Real, J. S.; Redlich, K.; Reed, R. J.; Rehman, A.; Reichelt, P.; Reicher, M.; Reidt, F.; Ren, X.; Renfordt, R.; Reolon, A. R.; Reshetin, A.; Rettig, F.; Revol, J.-P.; Reygers, K.; Riabov, V.; Ricci, R. A.; Richert, T.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Ristea, C.; Rivetti, A.; Rocco, E.; Rodríguez Cahuantzi, M.; Rodriguez Manso, A.; Røed, K.; Rogochaya, E.; Rohr, D.; Röhrich, D.; Romita, R.; Ronchetti, F.; Ronflette, L.; Rosnet, P.; Rossi, A.; Roukoutakis, F.; Roy, A.; Roy, C.; Roy, P.; Rubio Montero, A. J.; Rui, R.; Russo, R.; Ryabinkin, E.; Ryabov, Y.; Rybicki, A.; Sadovsky, S.; Šafařík, K.; Sahlmuller, B.; Sahoo, P.; Sahoo, R.; Sahoo, S.; Sahu, P. K.; Saini, J.; Sakai, S.; Saleh, M. A.; Salgado, C. A.; Salzwedel, J.; Sambyal, S.; Samsonov, V.; Sanchez Castro, X.; Šándor, L.; Sandoval, A.; Sano, M.; Santagati, G.; Sarkar, D.; Scapparone, E.; Scarlassara, F.; Scharenberg, R. P.; Schiaua, C.; Schicker, R.; Schmidt, C.; Schmidt, H. R.; Schuchmann, S.; Schukraft, J.; Schulc, M.; Schuster, T.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, R.; Seeder, K. S.; Seger, J. E.; Sekiguchi, Y.; Selyuzhenkov, I.; Senosi, K.; Seo, J.; Serradilla, E.; Sevcenco, A.; Shabanov, A.; Shabetai, A.; Shadura, O.; Shahoyan, R.; Shangaraev, A.; Sharma, A.; Sharma, N.; Shigaki, K.; Shtejer, K.; Sibiriak, Y.; Siddhanta, S.; Sielewicz, K. M.; Siemiarczuk, T.; Silvermyr, D.; Silvestre, C.; Simatovic, G.; Simonetti, G.; Singaraju, R.; Singh, R.; Singha, S.; Singhal, V.; Sinha, B. C.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T. B.; Slupecki, M.; Smirnov, N.; Snellings, R. J. M.; Snellman, T. W.; Søgaard, C.; Soltz, R.; Song, J.; Song, M.; Song, Z.; Soramel, F.; Sorensen, S.; Spacek, M.; Spiriti, E.; Sputowska, I.; Spyropoulou-Stassinaki, M.; Srivastava, B. K.; Stachel, J.; Stan, I.; Stefanek, G.; Steinpreis, M.; Stenlund, E.; Steyn, G.; Stiller, J. H.; Stocco, D.; Strmen, P.; Suaide, A. A. P.; Sugitate, T.; Suire, C.; Suleymanov, M.; Sultanov, R.; Šumbera, M.; Symons, T. J. M.; Szabo, A.; Szanto de Toledo, A.; Szarka, I.; Szczepankiewicz, A.; Szymanski, M.; Takahashi, J.; Tanaka, N.; Tangaro, M. A.; Tapia Takaki, J. D.; Tarantola Peloni, A.; Tariq, M.; Tarzila, M. G.; Tauro, A.; Tejeda Muñoz, G.; Telesca, A.; Terasaki, K.; Terrevoli, C.; Teyssier, B.; Thäder, J.; Thomas, D.; Tieulent, R.; Timmins, A. R.; Toia, A.; Trogolo, S.; Trubnikov, V.; Trzaska, W. H.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Tveter, T. S.; Ullaland, K.; Uras, A.; Usai, G. L.; Utrobicic, A.; Vajzer, M.; Vala, M.; Valencia Palomo, L.; Vallero, S.; Van Der Maarel, J.; Van Hoorne, J. W.; van Leeuwen, M.; Vanat, T.; Vande Vyvre, P.; Varga, D.; Vargas, A.; Vargyas, M.; Varma, R.; Vasileiou, M.; Vasiliev, A.; Vauthier, A.; Vechernin, V.; Veen, A. M.; Veldhoen, M.; Velure, A.; Venaruzzo, M.; Vercellin, E.; Vergara Limón, S.; Vernet, R.; Verweij, M.; Vickovic, L.; Viesti, G.; Viinikainen, J.; Vilakazi, Z.; Villalobos Baillie, O.; Vinogradov, A.; Vinogradov, L.; Vinogradov, Y.; Virgili, T.; Vislavicius, V.; Viyogi, Y. P.; Vodopyanov, A.; Völkl, M. A.; Voloshin, K.; Voloshin, S. A.; Volpe, G.; von Haller, B.; Vorobyev, I.; Vranic, D.; Vrláková, J.; Vulpescu, B.; Vyushin, A.; Wagner, B.; Wagner, J.; Wang, H.; Wang, M.; Wang, Y.; Watanabe, D.; Weber, M.; Weber, S. G.; Wessels, J. P.; Westerhoff, U.; Wiechula, J.; Wikne, J.; Wilde, M.; Wilk, G.; Wilkinson, J.; Williams, M. C. S.; Windelband, B.; Winn, M.; Yaldo, C. G.; Yamaguchi, Y.; Yang, H.; Yang, P.; Yano, S.; Yasnopolskiy, S.; Yin, Z.; Yokoyama, H.; Yoo, I.-K.; Yurchenko, V.; Yushmanov, I.; Zaborowska, A.; Zaccolo, V.; Zaman, A.; Zampolli, C.; Zanoli, H. J. C.; Zaporozhets, S.; Zarochentsev, A.; Závada, P.; Zaviyalov, N.; Zbroszczyk, H.; Zgura, I. S.; Zhalov, M.; Zhang, H.; Zhang, X.; Zhang, Y.; Zhao, C.; Zhigareva, N.; Zhou, D.; Zhou, Y.; Zhou, Z.; Zhu, H.; Zhu, J.; Zhu, X.; Zichichi, A.; Zimmermann, A.; Zimmermann, M. B.; Zinovjev, G.; Zyzak, M.

2016-01-01

We present results of a search for two hypothetical strange dibaryon states, i.e. the H-dibaryon and the possible Λn ‾ bound state. The search is performed with the ALICE detector in central (0-10%) Pb-Pb collisions at √{sNN} = 2.76 TeV, by invariant mass analysis in the decay modes Λn ‾ → d ‾π+ and H-dibaryon → Λpπ-. No evidence for these bound states is observed. Upper limits are determined at 99% confidence level for a wide range of lifetimes and for the full range of branching ratios. The results are compared to thermal, coalescence and hybrid UrQMD model expectations, which describe correctly the production of other loosely bound states, like the deuteron and the hypertriton.

Extracting Loop Bounds for WCET Analysis Using the Instrumentation Point Graph

NASA Astrophysics Data System (ADS)

Betts, A.; Bernat, G.

2009-05-01

Every calculation engine proposed in the literature of Worst-Case Execution Time (WCET) analysis requires upper bounds on loop iterations. Existing mechanisms to procure this information are either error prone, because they are gathered from the end-user, or limited in scope, because automatic analyses target very specific loop structures. In this paper, we present a technique that obtains bounds completely automatically for arbitrary loop structures. In particular, we show how to employ the Instrumentation Point Graph (IPG) to parse traces of execution (generated by an instrumented program) in order to extract bounds relative to any loop-nesting level. With this technique, therefore, non-rectangular dependencies between loops can be captured, allowing more accurate WCET estimates to be calculated. We demonstrate the improvement in accuracy by comparing WCET estimates computed through our HMB framework against those computed with state-of-the-art techniques.

Search for weakly decaying Λ n - and ΛΛ exotic bound states in central Pb–Pb collisions at s NN = 2.76  TeV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adam, J.; Adamová, D.; Aggarwal, M. M.

Here, we present results of a search for two hypothetical strange dibaryon states, i.e. the H-dibaryon and the possiblemore » $$\\overline{Λn}$$ bound state. The search is performed with the ALICE detector in central (0-10%) Pb-Pb collisions at $$\\sqrt{s}$$$_ {NN}$$ = 2.76 TeV, by invariant mass analysis in the decay modes $$\\overline{Λn}$$ → $$\\bar{d}$$π + and H-dibaryon →Λpπ -. No evidence for these bound states is observed. Upper limits are determined at 99% confidence level for a wide range of lifetimes and for the full range of branching ratios. The results are compared to thermal, coalescence and hybrid UrQMD model expectations, which describe correctly the production of other loosely bound states, like the deuteron and the hypertriton.« less

Marathon: An Open Source Software Library for the Analysis of Markov-Chain Monte Carlo Algorithms

PubMed Central

Rechner, Steffen; Berger, Annabell

2016-01-01

We present the software library marathon, which is designed to support the analysis of sampling algorithms that are based on the Markov-Chain Monte Carlo principle. The main application of this library is the computation of properties of so-called state graphs, which represent the structure of Markov chains. We demonstrate applications and the usefulness of marathon by investigating the quality of several bounding methods on four well-known Markov chains for sampling perfect matchings and bipartite graphs. In a set of experiments, we compute the total mixing time and several of its bounds for a large number of input instances. We find that the upper bound gained by the famous canonical path method is often several magnitudes larger than the total mixing time and deteriorates with growing input size. In contrast, the spectral bound is found to be a precise approximation of the total mixing time. PMID:26824442

Information models of software productivity - Limits on productivity growth

NASA Technical Reports Server (NTRS)

Tausworthe, Robert C.

1992-01-01

Research into generalized information-metric models of software process productivity establishes quantifiable behavior and theoretical bounds. The models establish a fundamental mathematical relationship between software productivity and the human capacity for information traffic, the software product yield (system size), information efficiency, and tool and process efficiencies. An upper bound is derived that quantifies average software productivity and the maximum rate at which it may grow. This bound reveals that ultimately, when tools, methodologies, and automated assistants have reached their maximum effective state, further improvement in productivity can only be achieved through increasing software reuse. The reuse advantage is shown not to increase faster than logarithmically in the number of reusable features available. The reuse bound is further shown to be somewhat dependent on the reuse policy: a general 'reuse everything' policy can lead to a somewhat slower productivity growth than a specialized reuse policy.

Coefficient of performance at maximum figure of merit and its bounds for low-dissipation Carnot-like refrigerators.

PubMed

Wang, Yang; Li, Mingxing; Tu, Z C; Hernández, A Calvo; Roco, J M M

2012-07-01

The figure of merit for refrigerators performing finite-time Carnot-like cycles between two reservoirs at temperature T(h) and T(c) (

Search for weakly decaying Λ n - and ΛΛ exotic bound states in central Pb–Pb collisions at s NN = 2.76  TeV

DOE PAGES

Adam, J.; Adamová, D.; Aggarwal, M. M.; ...

2016-11-28

Here, we present results of a search for two hypothetical strange dibaryon states, i.e. the H-dibaryon and the possiblemore » $$\\overline{Λn}$$ bound state. The search is performed with the ALICE detector in central (0-10%) Pb-Pb collisions at $$\\sqrt{s}$$$_ {NN}$$ = 2.76 TeV, by invariant mass analysis in the decay modes $$\\overline{Λn}$$ → $$\\bar{d}$$π + and H-dibaryon →Λpπ -. No evidence for these bound states is observed. Upper limits are determined at 99% confidence level for a wide range of lifetimes and for the full range of branching ratios. The results are compared to thermal, coalescence and hybrid UrQMD model expectations, which describe correctly the production of other loosely bound states, like the deuteron and the hypertriton.« less

Resistivity bound for hydrodynamic bad metals

PubMed Central

Lucas, Andrew; Hartnoll, Sean A.

2017-01-01

We obtain a rigorous upper bound on the resistivity ρ of an electron fluid whose electronic mean free path is short compared with the scale of spatial inhomogeneities. When such a hydrodynamic electron fluid supports a nonthermal diffusion process—such as an imbalance mode between different bands—we show that the resistivity bound becomes ρ≲AΓ. The coefficient A is independent of temperature and inhomogeneity lengthscale, and Γ is a microscopic momentum-preserving scattering rate. In this way, we obtain a unified mechanism—without umklapp—for ρ∼T2 in a Fermi liquid and the crossover to ρ∼T in quantum critical regimes. This behavior is widely observed in transition metal oxides, organic metals, pnictides, and heavy fermion compounds and has presented a long-standing challenge to transport theory. Our hydrodynamic bound allows phonon contributions to diffusion constants, including thermal diffusion, to directly affect the electrical resistivity. PMID:29073054

Interferometric tests of Planckian quantum geometry models

DOE PAGES

Kwon, Ohkyung; Hogan, Craig J.

2016-04-19

The effect of Planck scale quantum geometrical effects on measurements with interferometers is estimated with standard physics, and with a variety of proposed extensions. It is shown that effects are negligible in standard field theory with canonically quantized gravity. Statistical noise levels are estimated in a variety of proposals for nonstandard metric fluctuations, and these alternatives are constrained using upper bounds on stochastic metric fluctuations from LIGO. Idealized models of several interferometer system architectures are used to predict signal noise spectra in a quantum geometry that cannot be described by a fluctuating metric, in which position noise arises from holographicmore » bounds on directional information. Lastly, predictions in this case are shown to be close to current and projected experimental bounds.« less

Integrability and chemical potential in the (3 + 1)-dimensional Skyrme model

NASA Astrophysics Data System (ADS)

Alvarez, P. D.; Canfora, F.; Dimakis, N.; Paliathanasis, A.

2017-10-01

Using a remarkable mapping from the original (3 + 1)dimensional Skyrme model to the Sine-Gordon model, we construct the first analytic examples of Skyrmions as well as of Skyrmions-anti-Skyrmions bound states within a finite box in 3 + 1 dimensional flat space-time. An analytic upper bound on the number of these Skyrmions-anti-Skyrmions bound states is derived. We compute the critical isospin chemical potential beyond which these Skyrmions cease to exist. With these tools, we also construct topologically protected time-crystals: time-periodic configurations whose time-dependence is protected by their non-trivial winding number. These are striking realizations of the ideas of Shapere and Wilczek. The critical isospin chemical potential for these time-crystals is determined.

Properties of Coulomb crystals: rigorous results.

PubMed

Cioslowski, Jerzy

2008-04-28

Rigorous equalities and bounds for several properties of Coulomb crystals are presented. The energy e(N) per particle pair is shown to be a nondecreasing function of the particle number N for all clusters described by double-power-law pairwise-additive potentials epsilon(r) that are unbound at both r-->0 and r-->infinity. A lower bound for the ratio of the mean reciprocal crystal radius and e(N) is derived. The leading term in the asymptotic expression for the shell capacity that appears in the recently introduced approximate model of Coulomb crystals is obtained, providing in turn explicit large-N asymptotics for e(N) and the mean crystal radius. In addition, properties of the harmonic vibrational spectra are investigated, producing an upper bound for the zero-point energy.

Calculating Reuse Distance from Source Code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narayanan, Sri Hari Krishna; Hovland, Paul

The efficient use of a system is of paramount importance in high-performance computing. Applications need to be engineered for future systems even before the architecture of such a system is clearly known. Static performance analysis that generates performance bounds is one way to approach the task of understanding application behavior. Performance bounds provide an upper limit on the performance of an application on a given architecture. Predicting cache hierarchy behavior and accesses to main memory is a requirement for accurate performance bounds. This work presents our static reuse distance algorithm to generate reuse distance histograms. We then use these histogramsmore » to predict cache miss rates. Experimental results for kernels studied show that the approach is accurate.« less

Energy efficient quantum machines

NASA Astrophysics Data System (ADS)

Abah, Obinna; Lutz, Eric

2017-05-01

We investigate the performance of a quantum thermal machine operating in finite time based on shortcut-to-adiabaticity techniques. We compute efficiency and power for a paradigmatic harmonic quantum Otto engine by taking the energetic cost of the shortcut driving explicitly into account. We demonstrate that shortcut-to-adiabaticity machines outperform conventional ones for fast cycles. We further derive generic upper bounds on both quantities, valid for any heat engine cycle, using the notion of quantum speed limit for driven systems. We establish that these quantum bounds are tighter than those stemming from the second law of thermodynamics.

An efficient method for generalized linear multiplicative programming problem with multiplicative constraints.

PubMed

Zhao, Yingfeng; Liu, Sanyang

2016-01-01

We present a practical branch and bound algorithm for globally solving generalized linear multiplicative programming problem with multiplicative constraints. To solve the problem, a relaxation programming problem which is equivalent to a linear programming is proposed by utilizing a new two-phase relaxation technique. In the algorithm, lower and upper bounds are simultaneously obtained by solving some linear relaxation programming problems. Global convergence has been proved and results of some sample examples and a small random experiment show that the proposed algorithm is feasible and efficient.

Bounds on strong field magneto-transport in three-dimensional composites

NASA Astrophysics Data System (ADS)

Briane, Marc; Milton, Graeme W.

2011-10-01

This paper deals with bounds satisfied by the effective non-symmetric conductivity of three-dimensional composites in the presence of a strong magnetic field. On the one hand, it is shown that for general composites the antisymmetric part of the effective conductivity cannot be bounded solely in terms of the antisymmetric part of the local conductivity, contrary to the columnar case studied by Briane and Milton [SIAM J. Appl. Math. 70(8), 3272-3286 (2010), 10.1137/100798090]. Thus a suitable rank-two laminate, the conductivity of which has a bounded antisymmetric part together with a high-contrast symmetric part, may generate an arbitrarily large antisymmetric part of the effective conductivity. On the other hand, bounds are provided which show that the antisymmetric part of the effective conductivity must go to zero if the upper bound on the antisymmetric part of the local conductivity goes to zero, and the symmetric part of the local conductivity remains bounded below and above. Elementary bounds on the effective moduli are derived assuming the local conductivity and the effective conductivity have transverse isotropy in the plane orthogonal to the magnetic field. New Hashin-Shtrikman type bounds for two-phase three-dimensional composites with a non-symmetric conductivity are provided under geometric isotropy of the microstructure. The derivation of the bounds is based on a particular variational principle symmetrizing the problem, and the use of Y-tensors involving the averages of the fields in each phase.

Static aeroelastic analysis and tailoring of missile control fins

NASA Technical Reports Server (NTRS)

Mcintosh, S. C., Jr.; Dillenius, M. F. E.

1989-01-01

A concept for enhancing the design of control fins for supersonic tactical missiles is described. The concept makes use of aeroelastic tailoring to create fin designs (for given planforms) that limit the variations in hinge moments that can occur during maneuvers involving high load factors and high angles of attack. It combines supersonic nonlinear aerodynamic load calculations with finite-element structural modeling, static and dynamic structural analysis, and optimization. The problem definition is illustrated. The fin is at least partly made up of a composite material. The layup is fixed, and the orientations of the material principal axes are allowed to vary; these are the design variables. The objective is the magnitude of the difference between the chordwise location of the center of pressure and its desired location, calculated for a given flight condition. Three types of constraints can be imposed: upper bounds on static displacements for a given set of load conditions, lower bounds on specified natural frequencies, and upper bounds on the critical flutter damping parameter at a given set of flight speeds and altitudes. The idea is to seek designs that reduce variations in hinge moments that would otherwise occur. The block diagram describes the operation of the computer program that accomplishes these tasks. There is an option for a single analysis in addition to the optimization.

Statistical mechanical estimation of the free energy of formation of E. coli biomass for use with macroscopic bioreactor balances.

PubMed

Grosz, R; Stephanopoulos, G

1983-09-01

The need for the determination of the free energy of formation of biomass in bioreactor second law balances is well established. A statistical mechanical method for the calculation of the free energy of formation of E. coli biomass is introduced. In this method, biomass is modelled to consist of a system of biopolymer networks. The partition function of this system is proposed to consist of acoustic and optical modes of vibration. Acoustic modes are described by Tarasov's model, the parameters of which are evaluated with the aid of low-temperature calorimetric data for the crystalline protein bovine chymotrypsinogen A. The optical modes are described by considering the low-temperature thermodynamic properties of biological monomer crystals such as amino acid crystals. Upper and lower bounds are placed on the entropy to establish the maximum error associated with the statistical method. The upper bound is determined by endowing the monomers in biomass with ideal gas properties. The lower bound is obtained by limiting the monomers to complete immobility. On this basis, the free energy of formation is fixed to within 10%. Proposals are made with regard to experimental verification of the calculated value and extension of the calculation to other types of biomass.

Bounds on light gluinos from the BEBC beam dump experiment

NASA Astrophysics Data System (ADS)

Cooper-Sarkar, A. M.; Parker, M. A.; Sarkar, S.; Aderholz, M.; Bostock, P.; Clayton, E. F.; Faccini-Turluer, M. L.; Grässler, H.; Guy, J.; Hulth, P. O.; Hultqvist, K.; Idschok, U.; Klein, H.; Kreutzmann, H.; Krstic, J.; Mobayyen, M. M.; Morrison, D. R. O.; Nellen, B.; Schmid, P.; Schmitz, N.; Talebzadeh, M.; Venus, W.; Vignaud, D.; Walck, Ch.; Wachsmuth, H.; Wünsch, B.; WA66 Collaboration

1985-10-01

Observational upper limits on anomalous neutral-current events in a proton beam dump experiment are used to constrain the possible hadroproduction and decay of light gluinos. These results require ifm g˜$̆4 GeV for ifm q˜ - minw.

5. Corridor A and Building No. 9962A (with white door). ...

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

5. Corridor A and Building No. 9962-A (with white door). In upper left is east side of Building No. 9952-B. - Madigan Hospital, Corridors & Ramps, Bounded by Wilson & McKinley Avenues & Garfield & Lincoln Streets, Tacoma, Pierce County, WA

Interpolation Inequalities and Spectral Estimates for Magnetic Operators

NASA Astrophysics Data System (ADS)

Dolbeault, Jean; Esteban, Maria J.; Laptev, Ari; Loss, Michael

2018-05-01

We prove magnetic interpolation inequalities and Keller-Lieb-Thir-ring estimates for the principal eigenvalue of magnetic Schr{\\"o}dinger operators. We establish explicit upper and lower bounds for the best constants and show by numerical methods that our theoretical estimates are accurate.

Liouville type theorems of a nonlinear elliptic equation for the V-Laplacian

NASA Astrophysics Data System (ADS)

Huang, Guangyue; Li, Zhi

2018-03-01

In this paper, we consider Liouville type theorems for positive solutions to the following nonlinear elliptic equation: Δ _V u+aulog u=0, where a is a nonzero real constant. By using gradient estimates, we obtain upper bounds of |\

Universal Binding and Recoil Corrections to Bound State g Factors in Hydrogenlike Ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eides, Michael I.; Martin, Timothy J. S.

2010-09-03

The leading relativistic and recoil corrections to bound state g factors of particles with arbitrary spin are calculated. It is shown that these corrections are universal for any spin and depend only on the free particle gyromagnetic ratios. To prove this universality we develop nonrelativistic quantum electrodynamics (NRQED) for charged particles with an arbitrary spin. The coefficients in the NRQED Hamiltonian for higher spin particles are determined only by the requirements of Lorentz invariance and local charge conservation in the respective relativistic theory. For spin one charged particles, the NRQED Hamiltonian follows from the renormalizable QED of the charged vectormore » bosons. We show that universality of the leading relativistic and recoil corrections can be explained with the help of the Bargmann-Michael-Telegdi equation.« less

Classical Physics and the Bounds of Quantum Correlations.

PubMed

Frustaglia, Diego; Baltanás, José P; Velázquez-Ahumada, María C; Fernández-Prieto, Armando; Lujambio, Aintzane; Losada, Vicente; Freire, Manuel J; Cabello, Adán

2016-06-24

A unifying principle explaining the numerical bounds of quantum correlations remains elusive, despite the efforts devoted to identifying it. Here, we show that these bounds are indeed not exclusive to quantum theory: for any abstract correlation scenario with compatible measurements, models based on classical waves produce probability distributions indistinguishable from those of quantum theory and, therefore, share the same bounds. We demonstrate this finding by implementing classical microwaves that propagate along meter-size transmission-line circuits and reproduce the probabilities of three emblematic quantum experiments. Our results show that the "quantum" bounds would also occur in a classical universe without quanta. The implications of this observation are discussed.

Taming the runaway problem of inflationary landscapes

NASA Astrophysics Data System (ADS)

Hall, Lawrence J.; Watari, Taizan; Yanagida, T. T.

2006-05-01

A wide variety of vacua, and their cosmological realization, may provide an explanation for the apparently anthropic choices of some parameters of particle physics and cosmology. If the probability on various parameters is weighted by volume, a flat potential for slow-roll inflation is also naturally understood, since the flatter the potential the larger the volume of the subuniverse. However, such inflationary landscapes have a serious problem, predicting an environment that makes it exponentially hard for observers to exist and giving an exponentially small probability for a moderate universe like ours. A general solution to this problem is proposed, and is illustrated in the context of inflaton decay and leptogenesis, leading to an upper bound on the reheating temperature in our subuniverse. In a particular scenario of chaotic inflation and nonthermal leptogenesis, predictions can be made for the size of CP violating phases, the rate of neutrinoless double beta decay and, in the case of theories with gauge-mediated weak-scale supersymmetry, for the fundamental scale of supersymmetry breaking.

Chiral phase structure of three flavor QCD at vanishing baryon number density

DOE PAGES

Bazavov, A.; Ding, H. -T.; Hegde, P.; ...

2017-04-12

In this paper, we investigate the phase structure of QCD with three degenerate quark flavors as a function of the degenerate quark masses at vanishing baryon number density. We use the highly improved staggered quarks on lattices with temporal extent N τ = 6 and perform calculations for six values of quark masses, which in the continuum limit correspond to pion masses in the range 80 MeV ≲ m π ≲ 230 MeV. By analyzing the volume and temperature dependence of the chiral condensate and chiral susceptibility, we find no direct evidence for a first-order phase transition in this rangemore » of pion mass values. Finally, relying on the universal scaling behaviors of the chiral observables near an anticipated chiral critical point, we estimate an upper bound for the critical pion mass m c π ≲ 50 MeV, below which a region of first-order chiral phase transition is favored.« less

Search for gamma-ray lines towards galaxy clusters with the Fermi-LAT

DOE PAGES

Anderson, B.; Zimmer, S.; Conrad, J.; ...

2016-02-09

We report on a search for monochromatic γ-ray features in the spectra of galaxy clusters observed by the Fermi Large Area Telescope. Galaxy clusters are the largest structures in the Universe that are bound by dark matter (DM), making them an important testing ground for possible selfinteractions or decays of the DM particles. Monochromatic γ-ray lines provide a unique signature due to the absence of astrophysical backgrounds and are as such considered a smoking-gun signature for new physics. An unbinned joint likelihood analysis of the sixteen most promising clusters using five years of data at energies between 10 and 400more » GeV revealed no significant features. For the case of self-annihilation, we set upper limits on the monochromatic velocity-averaged interaction cross section. These limits are compatible with those obtained from observations of the Galactic Center, albeit weaker due to the larger distance to the studied clusters.« less

Non-minimally coupled f(R) cosmology

NASA Astrophysics Data System (ADS)

Thakur, Shruti; Sen, Anjan A.; Seshadri, T. R.

2011-02-01

We investigate the consequences of non-minimal gravitational coupling to matter and study how it differs from the case of minimal coupling by choosing certain simple forms for the nature of coupling. The values of the parameters are specified at z=0 (present epoch) and the equations are evolved backwards to calculate the evolution of cosmological parameters. We find that the Hubble parameter evolves more slowly in non-minimal coupling case as compared to the minimal coupling case. In both the cases, the universe accelerates around present time, and enters the decelerating regime in the past. Using the latest Union2 dataset for supernova Type Ia observations as well as the data for baryon acoustic oscillation (BAO) from SDSS observations, we constraint the parameters of Linder exponential model in the two different approaches. We find that there is an upper bound on model parameter in minimal coupling. But for non-minimal coupling case, there is range of allowed values for the model parameter.

2D CFT partition functions at late times

NASA Astrophysics Data System (ADS)

Dyer, Ethan; Gur-Ari, Guy

2017-08-01

We consider the late time behavior of the analytically continued partition function Z( β + it) Z( β - it) in holographic 2 d CFTs. This is a probe of information loss in such theories and in their holographic duals. We show that each Virasoro character decays in time, and so information is not restored at the level of individual characters. We identify a universal decaying contribution at late times, and conjecture that it describes the behavior of generic chaotic 2 d CFTs out to times that are exponentially large in the central charge. It was recently suggested that at sufficiently late times one expects a crossover to random matrix behavior. We estimate an upper bound on the crossover time, which suggests that the decay is followed by a parametrically long period of late time growth. Finally, we discuss gravitationally-motivated integrable theories and show how information is restored at late times by a series of characters. This hints at a possible bulk mechanism, where information is restored by an infinite sum over non-perturbative saddles.

Electroweak Kaluza-Klein dark matter

DOE PAGES

Flacke, Thomas; Kang, Dong Woo; Kong, Kyoungchul; ...

2017-04-07

In models with universal extra dimensions (UED), the lightest Kaluza-Klein excitation of neutral electroweak gauge bosons is a stable, weakly interacting massive particle and thus is a candidate for dark matter thanks to Kaluza-Klein parity. We examine concrete model realizations of such dark matter in the context of non-minimal UED extensions. The boundary localized kinetic terms for the electroweak gauge bosons lead to a non-trivial mixing among the first Kaluza-Klein excitations of themore » $${\\rm SU}(2)_W$$ and $${\\rm U}(1)_Y$$ gauge bosons and the resultant low energy phenomenology is rich. We investigate implications of various experiments including low energy electroweak precision measurements, direct and indirect detection of dark matter particles and direct collider searches at the LHC. Furthermore, we show that the electroweak Kaluza-Klein dark matter can be as heavy as 2.4 TeV, which is significantly higher than $1.3$ TeV as is indicated as an upper bound in the minimal UED model.« less

Yukawa unification in an SO(10) SUSY GUT: SUSY on the edge

NASA Astrophysics Data System (ADS)

Poh, Zijie; Raby, Stuart

2015-07-01

In this paper we analyze Yukawa unification in a three family SO(10) SUSY GUT. We perform a global χ2 analysis and show that supersymmetry (SUSY) effects do not decouple even though the universal scalar mass parameter at the grand unified theory (GUT) scale, m16, is found to lie between 15 and 30 TeV with the best fit given for m16≈25 TeV . Note, SUSY effects do not decouple since stops and bottoms have mass of order 5 TeV, due to renormalization group running from MGUT. The model has many testable predictions. Gauginos are the lightest sparticles and the light Higgs boson is very much standard model-like. The model is consistent with flavor and C P observables with the BR (μ →e γ ) close to the experimental upper bound. With such a large value of m16 we clearly cannot be considered "natural" SUSY nor are we "split" SUSY. We are thus in the region in between or "SUSY on the edge."

The evolving Planck mass in classically scale-invariant theories

NASA Astrophysics Data System (ADS)

Kannike, K.; Raidal, M.; Spethmann, C.; Veermäe, H.

2017-04-01

We consider classically scale-invariant theories with non-minimally coupled scalar fields, where the Planck mass and the hierarchy of physical scales are dynamically generated. The classical theories possess a fixed point, where scale invariance is spontaneously broken. In these theories, however, the Planck mass becomes unstable in the presence of explicit sources of scale invariance breaking, such as non-relativistic matter and cosmological constant terms. We quantify the constraints on such classical models from Big Bang Nucleosynthesis that lead to an upper bound on the non-minimal coupling and require trans-Planckian field values. We show that quantum corrections to the scalar potential can stabilise the fixed point close to the minimum of the Coleman-Weinberg potential. The time-averaged motion of the evolving fixed point is strongly suppressed, thus the limits on the evolving gravitational constant from Big Bang Nucleosynthesis and other measurements do not presently constrain this class of theories. Field oscillations around the fixed point, if not damped, contribute to the dark matter density of the Universe.

Activating distillation with an infinitesimal amount of bound entanglement.

PubMed

Vollbrecht, Karl Gerd H; Wolf, Michael M

2002-06-17

We show that bipartite quantum states of any dimension, which do not have a positive partial transpose (NPPT), become 1-distillable when one adds an infinitesimal amount of bound entanglement. To this end we investigate the activation properties of a new class of symmetric bound entangled states of full rank. It is shown that in this set there exist universal activator states capable of activating the distillation of any NPPT state. The result shows that even a small amount of bound entanglement can be useful for quantum information purposes.

Bekenstein bounds, Penrose inequalities, and black hole formation

NASA Astrophysics Data System (ADS)

Jaracz, Jaroslaw S.; Khuri, Marcus A.

2018-06-01

A universal geometric inequality for bodies relating energy, size, angular momentum, and charge is naturally implied by Bekenstein's entropy bounds. We establish versions of this inequality for axisymmetric bodies satisfying appropriate energy conditions, thus lending credence to the most general form of Bekenstein's bound. Similar techniques are then used to prove a Penrose-like inequality in which the ADM energy is bounded from below in terms of horizon area, angular momentum, and charge. Lastly, new criteria for the formation of black holes is presented involving concentration of angular momentum, charge, and nonelectromagnetic matter energy.

Evaluating the Potential Importance of Monoterpene Degradation for Global Acetone Production

NASA Astrophysics Data System (ADS)

Kelp, M. M.; Brewer, J.; Keller, C. A.; Fischer, E. V.

2015-12-01

Acetone is one of the most abundant volatile organic compounds (VOCs) in the atmosphere, but estimates of the global source of acetone vary widely. A better understanding of acetone sources is essential because acetone serves as a source of HOx in the upper troposphere and as a precursor to the NOx reservoir species peroxyacetyl nitrate (PAN). Although there are primary anthropogenic and pyrogenic sources of acetone, the dominant acetone sources are thought to be from direct biogenic emissions and photochemical production, particularly from the oxidation of iso-alkanes. Recent work suggests that the photochemical degradation of monoterpenes may also represent a significant contribution to global acetone production. We investigate that hypothesis using the GEOS-Chem chemical transport model. In this work, we calculate the emissions of eight terpene species (α-pinene, β-pinene, limonene, Δ3-carene, myrcene, sabinene, trans-β-ocimene, and an 'other monoterpenes' category which contains 34 other trace species) and couple these with upper and lower bound literature yields from species-specific chamber studies. We compare the simulated acetone distributions against in situ acetone measurements from a global suite of NASA aircraft campaigns. When simulating an upper bound on yields, the model-to-measurement comparison improves for North America at both the surface and in the upper troposphere. The inclusion of acetone production from monoterpene degradation also improves the ability of the model to reproduce observations of acetone in East Asian outflow. However, in general the addition of monoterpenes degrades the model comparison for the Southern Hemisphere.

Probing the size of extra dimensions with gravitational wave astronomy

NASA Astrophysics Data System (ADS)

Yagi, Kent; Tanahashi, Norihiro; Tanaka, Takahiro

2011-04-01

In the Randall-Sundrum II braneworld model, it has been conjectured, according to the AdS/CFT correspondence, that a brane-localized black hole (BH) larger than the bulk AdS curvature scale ℓ cannot be static, and it is dual to a four-dimensional BH emitting Hawking radiation through some quantum fields. In this scenario, the number of the quantum field species is so large that this radiation changes the orbital evolution of a BH binary. We derived the correction to the gravitational waveform phase due to this effect and estimated the upper bounds on ℓ by performing Fisher analyses. We found that the Deci-Hertz Interferometer Gravitational Wave Observatory and the Big Bang Observatory (DECIGO/BBO) can give a stronger constraint than the current tabletop result by detecting gravitational waves from small mass BH/BH and BH/neutron star (NS) binaries. Furthermore, DECIGO/BBO is expected to detect 105 BH/NS binaries per year. Taking this advantage, we find that DECIGO/BBO can actually measure ℓ down to ℓ=0.33μm for a 5 yr observation if we know that binaries are circular a priori. This is about 40 times smaller than the upper bound obtained from the tabletop experiment. On the other hand, when we take eccentricities into binary parameters, the detection limit weakens to ℓ=1.5μm due to strong degeneracies between ℓ and eccentricities. We also derived the upper bound on ℓ from the expected detection number of extreme mass ratio inspirals with LISA and BH/NS binaries with DECIGO/BBO, extending the discussion made recently by McWilliams [Phys. Rev. Lett. 104, 141601 (2010)PRLTAO0031-900710.1103/PhysRevLett.104.141601]. We found that these less robust constraints are weaker than the ones from phase differences.

Stability results for multi-layer radial Hele-Shaw and porous media flows

NASA Astrophysics Data System (ADS)

Gin, Craig; Daripa, Prabir

2015-01-01

Motivated by stability problems arising in the context of chemical enhanced oil recovery, we perform linear stability analysis of Hele-Shaw and porous media flows in radial geometry involving an arbitrary number of immiscible fluids. Key stability results obtained and their relevance to the stabilization of fingering instability are discussed. Some of the key results, among many others, are (i) absolute upper bounds on the growth rate in terms of the problem data; (ii) validation of these upper bound results against exact computation for the case of three-layer flows; (iii) stability enhancing injection policies; (iv) asymptotic limits that reduce these radial flow results to similar results for rectilinear flows; and (v) the stabilizing effect of curvature of the interfaces. Multi-layer radial flows have been found to have the following additional distinguishing features in comparison to rectilinear flows: (i) very long waves, some of which can be physically meaningful, are stable; and (ii) eigenvalues can be complex for some waves depending on the problem data, implying that the dispersion curves for one or more waves can contact each other. Similar to the rectilinear case, these results can be useful in providing insight into the interfacial instability transfer mechanism as the problem data are varied. Moreover, these can be useful in devising smart injection policies as well as controlling the complexity of the long-term dynamics when drops of various immiscible fluids intersperse among each other. As an application of the upper bound results, we provide stabilization criteria and design an almost stable multi-layer system by adding many layers of fluid with small positive jumps in viscosity in the direction of the basic flow.

Mechanical metamaterials at the theoretical limit of isotropic elastic stiffness

NASA Astrophysics Data System (ADS)

Berger, J. B.; Wadley, H. N. G.; McMeeking, R. M.

2017-02-01

A wide variety of high-performance applications require materials for which shape control is maintained under substantial stress, and that have minimal density. Bio-inspired hexagonal and square honeycomb structures and lattice materials based on repeating unit cells composed of webs or trusses, when made from materials of high elastic stiffness and low density, represent some of the lightest, stiffest and strongest materials available today. Recent advances in 3D printing and automated assembly have enabled such complicated material geometries to be fabricated at low (and declining) cost. These mechanical metamaterials have properties that are a function of their mesoscale geometry as well as their constituents, leading to combinations of properties that are unobtainable in solid materials; however, a material geometry that achieves the theoretical upper bounds for isotropic elasticity and strain energy storage (the Hashin-Shtrikman upper bounds) has yet to be identified. Here we evaluate the manner in which strain energy distributes under load in a representative selection of material geometries, to identify the morphological features associated with high elastic performance. Using finite-element models, supported by analytical methods, and a heuristic optimization scheme, we identify a material geometry that achieves the Hashin-Shtrikman upper bounds on isotropic elastic stiffness. Previous work has focused on truss networks and anisotropic honeycombs, neither of which can achieve this theoretical limit. We find that stiff but well distributed networks of plates are required to transfer loads efficiently between neighbouring members. The resulting low-density mechanical metamaterials have many advantageous properties: their mesoscale geometry can facilitate large crushing strains with high energy absorption, optical bandgaps and mechanically tunable acoustic bandgaps, high thermal insulation, buoyancy, and fluid storage and transport. Our relatively simple design can be manufactured using origami-like sheet folding and bonding methods.

Mechanical metamaterials at the theoretical limit of isotropic elastic stiffness.

PubMed

Berger, J B; Wadley, H N G; McMeeking, R M

2017-03-23

A wide variety of high-performance applications require materials for which shape control is maintained under substantial stress, and that have minimal density. Bio-inspired hexagonal and square honeycomb structures and lattice materials based on repeating unit cells composed of webs or trusses, when made from materials of high elastic stiffness and low density, represent some of the lightest, stiffest and strongest materials available today. Recent advances in 3D printing and automated assembly have enabled such complicated material geometries to be fabricated at low (and declining) cost. These mechanical metamaterials have properties that are a function of their mesoscale geometry as well as their constituents, leading to combinations of properties that are unobtainable in solid materials; however, a material geometry that achieves the theoretical upper bounds for isotropic elasticity and strain energy storage (the Hashin-Shtrikman upper bounds) has yet to be identified. Here we evaluate the manner in which strain energy distributes under load in a representative selection of material geometries, to identify the morphological features associated with high elastic performance. Using finite-element models, supported by analytical methods, and a heuristic optimization scheme, we identify a material geometry that achieves the Hashin-Shtrikman upper bounds on isotropic elastic stiffness. Previous work has focused on truss networks and anisotropic honeycombs, neither of which can achieve this theoretical limit. We find that stiff but well distributed networks of plates are required to transfer loads efficiently between neighbouring members. The resulting low-density mechanical metamaterials have many advantageous properties: their mesoscale geometry can facilitate large crushing strains with high energy absorption, optical bandgaps and mechanically tunable acoustic bandgaps, high thermal insulation, buoyancy, and fluid storage and transport. Our relatively simple design can be manufactured using origami-like sheet folding and bonding methods.

MRI-based assessment of the pineal gland in a large population of children aged 0-5 years and comparison with pineoblastoma: part I, the solid gland.

PubMed

Galluzzi, Paolo; de Jong, Marcus C; Sirin, Selma; Maeder, Philippe; Piu, Pietro; Cerase, Alfonso; Monti, Lucia; Brisse, Hervé J; Castelijns, Jonas A; de Graaf, Pim; Goericke, Sophia L

2016-07-01

Differentiation between normal solid (non-cystic) pineal glands and pineal pathologies on brain MRI is difficult. The aim of this study was to assess the size of the solid pineal gland in children (0-5 years) and compare the findings with published pineoblastoma cases. We retrospectively analyzed the size (width, height, planimetric area) of solid pineal glands in 184 non-retinoblastoma patients (73 female, 111 male) aged 0-5 years on MRI. The effect of age and gender on gland size was evaluated. Linear regression analysis was performed to analyze the relation between size and age. Ninety-nine percent prediction intervals around the mean were added to construct a normal size range per age, with the upper bound of the predictive interval as the parameter of interest as a cutoff for normalcy. There was no significant interaction of gender and age for all the three pineal gland parameters (width, height, and area). Linear regression analysis gave 99 % upper prediction bounds of 7.9, 4.8, and 25.4 mm(2), respectively, for width, height, and area. The slopes (size increase per month) of each parameter were 0.046, 0.023, and 0.202, respectively. Ninety-three percent (95 % CI 66-100 %) of asymptomatic solid pineoblastomas were larger in size than the 99 % upper bound. This study establishes norms for solid pineal gland size in non-retinoblastoma children aged 0-5 years. Knowledge of the size of the normal pineal gland is helpful for detection of pineal gland abnormalities, particularly pineoblastoma.

Optimizing Retransmission Threshold in Wireless Sensor Networks

PubMed Central

Bi, Ran; Li, Yingshu; Tan, Guozhen; Sun, Liang

2016-01-01

The retransmission threshold in wireless sensor networks is critical to the latency of data delivery in the networks. However, existing works on data transmission in sensor networks did not consider the optimization of the retransmission threshold, and they simply set the same retransmission threshold for all sensor nodes in advance. The method did not take link quality and delay requirement into account, which decreases the probability of a packet passing its delivery path within a given deadline. This paper investigates the problem of finding optimal retransmission thresholds for relay nodes along a delivery path in a sensor network. The object of optimizing retransmission thresholds is to maximize the summation of the probability of the packet being successfully delivered to the next relay node or destination node in time. A dynamic programming-based distributed algorithm for finding optimal retransmission thresholds for relay nodes along a delivery path in the sensor network is proposed. The time complexity is OnΔ·max1≤i≤n{ui}, where ui is the given upper bound of the retransmission threshold of sensor node i in a given delivery path, n is the length of the delivery path and Δ is the given upper bound of the transmission delay of the delivery path. If Δ is greater than the polynomial, to reduce the time complexity, a linear programming-based (1+pmin)-approximation algorithm is proposed. Furthermore, when the ranges of the upper and lower bounds of retransmission thresholds are big enough, a Lagrange multiplier-based distributed O(1)-approximation algorithm with time complexity O(1) is proposed. Experimental results show that the proposed algorithms have better performance. PMID:27171092

Formation of eyes in large-scale cyclonic vortices

NASA Astrophysics Data System (ADS)

Oruba, L.; Davidson, P. A.; Dormy, E.

2018-01-01

We present numerical simulations of steady, laminar, axisymmetric convection of a Boussinesq fluid in a shallow, rotating, cylindrical domain. The flow is driven by an imposed vertical heat flux and shaped by the background rotation of the domain. The geometry is inspired by that of tropical cyclones and the global flow pattern consists of a shallow swirling vortex combined with a poloidal flow in the r -z plane which is predominantly inward near the bottom boundary and outward along the upper surface. Our numerical experiments confirm that, as suggested in our recent work [L. Oruba et al., J. Fluid Mech. 812, 890 (2017), 10.1017/jfm.2016.846], an eye forms at the center of the vortex which is reminiscent of that seen in a tropical cyclone and is characterized by a local reversal in the direction of the poloidal flow. We establish scaling laws for the flow and map out the conditions under which an eye will, or will not, form. We show that, to leading order, the velocity scales with V =(αg β ) 1 /2H , where g is gravity, α is the expansion coefficient, β is the background temperature gradient, and H is the depth of the domain. We also show that the two most important parameters controlling the flow are Re =V H /ν and Ro =V /(Ω H ) , where Ω is the background rotation rate and ν the viscosity. The Prandtl number and aspect ratio also play an important, if secondary, role. Finally, and most importantly, we establish the criteria required for eye formation. These consist of a lower bound on Re , upper and lower bounds on Ro , and an upper bound on the Ekman number.

Correlations Between the Cosmic X-Ray and Microwave Backgrounds: Constraints on a Cosmological Constant

NASA Technical Reports Server (NTRS)

Boughn, S. P.; Crittenden, R. G.; Turok, N. G.

1998-01-01

In universes with significant curvature or cosmological constant, cosmic microwave background (CMB) anisotropies are created very recently via the Rees-Sciama or integrated Sachs-Wolfe effects. This causes the CMB anisotropies to become partially correlated with the local matter density (z less than 4). We examine the prospects of using the hard (2- 10 keV) X-ray background as a probe of the local density and the measured correlation between the HEAO1 A2 X-ray survey and the 4-year COBE-DMR map to obtain a constraint on the cosmological constant. The 95% confidence level upper limit on the cosmological constant is OMega(sub Lambda) less than or equal to 0.5, assuming that the observed fluctuations in the X-ray map result entirely from large scale structure. (This would also imply that the X-rays trace matter with a bias factor of b(sub x) approx. = 5.6 Omega(sub m, sup 0.53)). This bound is weakened considerably if a large portion of the X-ray fluctuations arise from Poisson noise from unresolved sources. For example, if one assumes that the X-ray bias is b(sub x) = 2, then the 95% confidence level upper limit is weaker, Omega(sub Lambda) less than or equal to 0.7. More stringent limits should be attainable with data from the next generation of CMB and X-ray background maps.

Needle-free jet injection for administration of influenza vaccine: a randomised non-inferiority trial.

PubMed

McAllister, Linda; Anderson, Jonathan; Werth, Kristen; Cho, Iksung; Copeland, Karen; Le Cam Bouveret, Nancy; Plant, David; Mendelman, Paul M; Cobb, David K

2014-08-23

Administration of vaccines by needle-free technology such as jet injection might offer an alternative to needles and syringes that avoids the issue of needle phobia and the risk of needle-stick injury. We aimed to assess the immunogenicity and safety of trivalent influenza vaccine given by needle-free jet injector compared with needle and syringe. For this randomised, comparator-controlled trial, we randomly assigned (1:1) healthy adults (aged 18-64 years) who attended one of four employee health clinics in the University of Colorado health system, with stratification by site, to receive one dose of the trivalent inactivated influenza vaccine Afluria given either intramuscularly with a needle-free jet injector (Stratis; PharmaJet, Golden, CO, USA) or with needle and syringe. Randomisation was done with a computer-generated randomisation schedule with a block size of 100. Because of the nature of the study, masking of participants was not possible. Immunogenicity was assessed by measurement of the hemagglutination inhibition antibody titres in serum for the three viral strains included in the vaccine. We included six coprimary endpoints: three strain-specific geometric mean titre ratios and the absolute differences in three strain-specific seroconversion rates. The immune response of the jet injector group was regarded as non-inferior to that of the needle and syringe group if both the upper bound of each of the three 95% CIs for the strain-specific geometric mean titre ratios was 1.5 or less, and the upper bound of the three 95% CIs for the strain-specific seroconversion rate differences was less than 10 percentage points. We used t test for group comparison. This study is registered with ClinicalTrials.gov, number NCT01688921. During the 2012-13 influenza season of the northern hemisphere, we allocated 1250 participants to receive vaccination by needle-free jet injector (n=627) or needle and syringe (n=623). In the intention-to-treat immunogenicity population, all participants with two serum samples were included (575 in the jet injector group and 574 in the needle and syringe group). The immune response to Afluria when given by needle-free jet injector met the criteria for non-inferiority for all six coprimary endpoints. The jet injector group met the geometric mean titre criterion for non-inferiority for the A/H1N1, A/H3N2, and B strains (upper bound of the 95% CI for the geometric mean titre ratios were 1·10 for A/H1N1, 1·17 for A/H3N2, and 1·04 for B strains). The jet injector group met the seroconversion rate criterion for non-inferiority for the A/H1N1, A/H3N2, and B strains (upper bound of the 95% CI of the seroconversion rate differences were 6·0% for A/H1N1, 7·0% for A/H3N2, and 5·7% for B strains). We recorded serious adverse events in three participants, none of which were study related. The immune response to influenza vaccine given with the jet injector device was non-inferior to the immune response to influenza vaccine given with needle and syringe. The device had a clinically acceptable safety profile, but was associated with a higher frequency of local injection site reactions than was the use of needle and syringe. The Stratis needle-free jet injector device could be used as an alternative method of administration of Afluria trivalent influenza vaccine. Biomedical Advanced Research and Development Authority (BARDA), PATH, bioCSL, and PharmaJet. Copyright © 2014 Elsevier Ltd. All rights reserved.

Supersymmetry searches in GUT models with non-universal scalar masses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cannoni, M.; Gómez, M.E.; Ellis, J.

2016-03-01

We study SO(10), SU(5) and flipped SU(5) GUT models with non-universal soft supersymmetry-breaking scalar masses, exploring how they are constrained by LHC supersymmetry searches and cold dark matter experiments, and how they can be probed and distinguished in future experiments. We find characteristic differences between the various GUT scenarios, particularly in the coannihilation region, which is very sensitive to changes of parameters. For example, the flipped SU(5) GUT predicts the possibility of ∼t{sub 1}−χ coannihilation, which is absent in the regions of the SO(10) and SU(5) GUT parameter spaces that we study. We use the relic density predictions in differentmore » models to determine upper bounds for the neutralino masses, and we find large differences between different GUT models in the sparticle spectra for the same LSP mass, leading to direct connections of distinctive possible experimental measurements with the structure of the GUT group. We find that future LHC searches for generic missing E{sub T}, charginos and stops will be able to constrain the different GUT models in complementary ways, as will the Xenon 1 ton and Darwin dark matter scattering experiments and future FERMI or CTA γ-ray searches.« less

Abridged Too Far? Credit Transfer: Examining the Transition Process from TAFE to University

ERIC Educational Resources Information Center

Millman, Theresa

2013-01-01

In responding to a global audience, universities are increasingly bound up in priorities of maintaining viability within landscapes of globalised market imperatives, and with changing paradigms of purpose; universities need to be accessible to all. In Australia, pathways to university provided by Credit Transfer have increased student mobility;…

Should Reproductive Anatomy Be Taught in University Health Courses?

ERIC Educational Resources Information Center

Powell, Brent; Fletcher, J. Sue

2013-01-01

There has been little research on undergraduate reproductive anatomy education. This pilot study explores knowledge of anatomical reproductive anatomy among university students in a lower division and upper division health course. Using a Qualtrics survey program, a convenience sample of 120 lower division and 157 upper division students for a…

Standard Model in multiscale theories and observational constraints

NASA Astrophysics Data System (ADS)

Calcagni, Gianluca; Nardelli, Giuseppe; Rodríguez-Fernández, David

2016-08-01

We construct and analyze the Standard Model of electroweak and strong interactions in multiscale spacetimes with (i) weighted derivatives and (ii) q -derivatives. Both theories can be formulated in two different frames, called fractional and integer picture. By definition, the fractional picture is where physical predictions should be made. (i) In the theory with weighted derivatives, it is shown that gauge invariance and the requirement of having constant masses in all reference frames make the Standard Model in the integer picture indistinguishable from the ordinary one. Experiments involving only weak and strong forces are insensitive to a change of spacetime dimensionality also in the fractional picture, and only the electromagnetic and gravitational sectors can break the degeneracy. For the simplest multiscale measures with only one characteristic time, length and energy scale t*, ℓ* and E*, we compute the Lamb shift in the hydrogen atom and constrain the multiscale correction to the ordinary result, getting the absolute upper bound t*<10-23 s . For the natural choice α0=1 /2 of the fractional exponent in the measure, this bound is strengthened to t*<10-29 s , corresponding to ℓ*<10-20 m and E*>28 TeV . Stronger bounds are obtained from the measurement of the fine-structure constant. (ii) In the theory with q -derivatives, considering the muon decay rate and the Lamb shift in light atoms, we obtain the independent absolute upper bounds t*<10-13 s and E*>35 MeV . For α0=1 /2 , the Lamb shift alone yields t*<10-27 s , ℓ*<10-19 m and E*>450 GeV .

A note on the WGC, effective field theory and clockwork within string theory

NASA Astrophysics Data System (ADS)

Ibáñez, Luis E.; Montero, Miguel

2018-02-01

It has been recently argued that Higgsing of theories with U(1) n gauge interactions consistent with the Weak Gravity Conjecture (WGC) may lead to effective field theories parametrically violating WGC constraints. The minimal examples typically involve Higgs scalars with a large charge with respect to a U(1) (e.g. charges ( Z, 1) in U(1)2 with Z ≫ 1). This type of Higgs multiplets play also a key role in clockwork U(1) theories. We study these issues in the context of heterotic string theory and find that, even if there is no new physics at the standard magnetic WGC scale Λ ˜ g IR M P , the string scale is just slightly above, at a scale ˜ √{k_{IR}}Λ. Here k IR is the level of the IR U(1) worldsheet current. We show that, unlike the standard magnetic cutoff, this bound is insensitive to subsequent Higgsing. One may argue that this constraint gives rise to no bound at the effective field theory level since k IR is model dependent and in general unknown. However there is an additional constraint to be taken into account, which is that the Higgsing scalars with large charge Z should be part of the string massless spectrum, which becomes an upper bound k IR ≤ k 0 2 , where k 0 is the level of the UV currents. Thus, for fixed k 0, Z cannot be made parametrically large. The upper bound on the charges Z leads to limitations on the size and structure of hierarchies in an iterated U(1) clockwork mechanism.

THE COOL ACCRETION DISK IN ESO 243-49 HLX-1: FURTHER EVIDENCE OF AN INTERMEDIATE-MASS BLACK HOLE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, Shane W.; Narayan, Ramesh; Zhu Yucong

2011-06-20

With an inferred bolometric luminosity exceeding 10{sup 42} erg s{sup -1}, HLX-1 in ESO 243-49 is the most luminous of ultraluminous X-ray sources and provides one of the strongest cases for the existence of intermediate-mass black holes. We obtain good fits to disk-dominated observations of the source with BHSPEC, a fully relativistic black hole accretion disk spectral model. Due to degeneracies in the model arising from the lack of independent constraints on inclination and black hole spin, there is a factor of 100 uncertainty in the best-fit black hole mass M. Nevertheless, spectral fitting of XMM-Newton observations provides robust lowermore » and upper limits with 3000 M{sub sun} {approx}< M {approx}< 3 x 10{sup 5} M{sub sun}, at 90% confidence, placing HLX-1 firmly in the intermediate-mass regime. The lower bound on M is entirely determined by matching the shape and peak energy of the thermal component in the spectrum. This bound is consistent with (but independent of) arguments based solely on the Eddington limit. Joint spectral modeling of the XMM-Newton data with more luminous Swift and Chandra observations increases the lower bound to 6000 M{sub sun}, but this tighter constraint is not independent of the Eddington limit. The upper bound on M is sensitive to the maximum allowed inclination i, and is reduced to M {approx}< 10{sup 5} M{sub sun} if we limit i {approx}< 75{sup 0}.« less

The Limb Infrared Monitor of the Stratosphere (LIMS) experiment

NASA Technical Reports Server (NTRS)

Russell, J. M.; Gille, J. C.

1978-01-01

The Limb Infrared Monitor of the Stratosphere is used to obtain vertical profiles and maps of temperature and the concentration of ozone, water vapor, nitrogen dioxide, and nitric acid for the region of the stratosphere bounded by the upper troposphere and the lower mesosphere.

RIEMANNIAN MANIFOLDS ADMITTING A CONFORMAL TRANSFORMATION GROUP

PubMed Central

Yano, Kentaro

1969-01-01

Let M be a Riemannian manifold with constant scalar curvature K which admits an infinitesimal conformal transformation. A necessary and sufficient condition in order that it be isometric with a sphere is obtained. Inequalities giving upper and lower bounds for K are also derived. PMID:16578692

An Upper Bound for Population Exposure Variability (SOT)

EPA Science Inventory

Tools for the rapid assessment of exposure potential are needed in order to put the results of rapidly-applied tools for assessing biological activity, such as ToxCast® and other high throughput methodologies, into a quantitative exposure context. The ExpoCast models (Wambaugh et...

Water Mass Map from Neutron Spectrometer

NASA Technical Reports Server (NTRS)

2003-01-01

December 8, 2003

This map shows the estimated lower limit of the water content of the upper meter of Martian soil. The estimates are derived from the hydrogen abundance measured by the neutron spectrometer component of the gamma ray spectrometer suite on NASA's Mars Odyssey spacecraft.

The highest water-mass fractions, exceeding 30 percent to well over 60 percent, are in the polar regions, beyond about 60 degrees latitude north or south. Farther from the poles, significant concentrations are in the area bound in longitude by minus 10 degrees to 50 degrees and in latitude by 30 degrees south to 40 degrees north, and in an area to the south and west of Olympus Mons (30 degrees to 0 degrees south latitude and minus 135 degrees to 110 degrees longitude).

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the 2001 Mars Odyssey mission for the NASA Office of Space Science in Washington. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson and NASA's Johnson Space Center, Houston, operate the science instruments. The gamma-ray spectrometer was provided by the University of Arizona in collaboration with the Russian Aviation and Space Agency, which provided the high-energy neutron detector, and the Los Alamos National Laboratories, New Mexico, which provided the neutron spectrometer. Lockheed Martin Space Systems, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL.

Ferromagnetic Potts models with multisite interaction

NASA Astrophysics Data System (ADS)

Schreiber, Nir; Cohen, Reuven; Haber, Simi

2018-03-01

We study the q -state Potts model with four-site interaction on a square lattice. Based on the asymptotic behavior of lattice animals, it is argued that when q ≤4 the system exhibits a second-order phase transition and when q >4 the transition is first order. The q =4 model is borderline. We find 1 /lnq to be an upper bound on Tc, the exact critical temperature. Using a low-temperature expansion, we show that 1 /(θ lnq ) , where θ >1 is a q -dependent geometrical term, is an improved upper bound on Tc. In fact, our findings support Tc=1 /(θ lnq ) . This expression is used to estimate the finite correlation length in first-order transition systems. These results can be extended to other lattices. Our theoretical predictions are confirmed numerically by an extensive study of the four-site interaction model using the Wang-Landau entropic sampling method for q =3 ,4 ,5 . In particular, the q =4 model shows an ambiguous finite-size pseudocritical behavior.

Extremal values on Zagreb indices of trees with given distance k-domination number.

PubMed

Pei, Lidan; Pan, Xiangfeng

2018-01-01

Let [Formula: see text] be a graph. A set [Formula: see text] is a distance k -dominating set of G if for every vertex [Formula: see text], [Formula: see text] for some vertex [Formula: see text], where k is a positive integer. The distance k -domination number [Formula: see text] of G is the minimum cardinality among all distance k -dominating sets of G . The first Zagreb index of G is defined as [Formula: see text] and the second Zagreb index of G is [Formula: see text]. In this paper, we obtain the upper bounds for the Zagreb indices of n -vertex trees with given distance k -domination number and characterize the extremal trees, which generalize the results of Borovićanin and Furtula (Appl. Math. Comput. 276:208-218, 2016). What is worth mentioning, for an n -vertex tree T , is that a sharp upper bound on the distance k -domination number [Formula: see text] is determined.

Pinning down inelastic dark matter in the Sun and in direct detection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blennow, Mattias; Clementz, Stefan; Herrero-Garcia, Juan, E-mail: emb@kth.se, E-mail: scl@kth.se, E-mail: juhg@kth.se

2016-04-01

We study the solar capture rate of inelastic dark matter with endothermic and/or exothermic interactions. By assuming that an inelastic dark matter signal will be observed in next generation direct detection experiments we can set a lower bound on the capture rate that is independent of the local dark matter density, the velocity distribution, the galactic escape velocity as well as the scattering cross section. In combination with upper limits from neutrino observatories we can place upper bounds on the annihilation channels leading to neutrinos. We find that, while endothermic scattering limits are weak in the isospin-conserving case, strong boundsmore » may be set for exothermic interactions, in particular in the spin-dependent case. Furthermore, we study the implications of observing two direct detection signals, in which case one can halo-independently obtain the dark matter mass and the mass splitting, and disentangle the endothermic/exothermic nature of the scattering. Finally we discuss isospin violation.« less

Diffusion Influenced Adsorption Kinetics.

PubMed

Miura, Toshiaki; Seki, Kazuhiko

2015-08-27

When the kinetics of adsorption is influenced by the diffusive flow of solutes, the solute concentration at the surface is influenced by the surface coverage of solutes, which is given by the Langmuir-Hinshelwood adsorption equation. The diffusion equation with the boundary condition given by the Langmuir-Hinshelwood adsorption equation leads to the nonlinear integro-differential equation for the surface coverage. In this paper, we solved the nonlinear integro-differential equation using the Grünwald-Letnikov formula developed to solve fractional kinetics. Guided by the numerical results, analytical expressions for the upper and lower bounds of the exact numerical results were obtained. The upper and lower bounds were close to the exact numerical results in the diffusion- and reaction-controlled limits, respectively. We examined the validity of the two simple analytical expressions obtained in the diffusion-controlled limit. The results were generalized to include the effect of dispersive diffusion. We also investigated the effect of molecular rearrangement of anisotropic molecules on surface coverage.

A method for paraplegic upper-body posture estimation during standing: a pilot study for rehabilitation purposes.

PubMed

Pages, Gaël; Ramdani, Nacim; Fraisse, Philippe; Guiraud, David

2009-06-01

This paper presents a contribution for restoring standing in paraplegia while using functional electrical stimulation (FES). Movement generation induced by FES remains mostly open looped and stimulus intensities are tuned empirically. To design an efficient closed-loop control, a preliminary study has been carried out to investigate the relationship between body posture and voluntary upper body movements. A methodology is proposed to estimate body posture in the sagittal plane using force measurements exerted on supporting handles during standing. This is done by setting up constraints related to the geometric equations of a two-dimensional closed chain model and the hand-handle interactions. All measured quantities are subject to an uncertainty assumed unknown but bounded. The set membership estimation problem is solved via interval analysis. Guaranteed uncertainty bounds are computed for the estimated postures. In order to test the feasibility of our methodology, experiments were carried out with complete spinal cord injured patients.

Non-linear collisional Penrose process: How much energy can a black hole release?

NASA Astrophysics Data System (ADS)

Nakao, Ken-ichi; Okawa, Hirotada; Maeda, Kei-ichi

2018-01-01

Energy extraction from a rotating or charged black hole is one of the fascinating issues in general relativity. The collisional Penrose process is one such extraction mechanism and has been reconsidered intensively since Bañados, Silk, and West pointed out the physical importance of very high energy collisions around a maximally rotating black hole. In order to get results analytically, the test particle approximation has been adopted so far. Successive works based on this approximation scheme have not yet revealed the upper bound on the efficiency of the energy extraction because of the lack of backreaction. In the Reissner-Nordström spacetime, by fully taking into account the self-gravity of the shells, we find that there is an upper bound on the extracted energy that is consistent with the area law of a black hole. We also show one particular scenario in which almost the maximum energy extraction is achieved even without the Bañados-Silk-West collision.

Optimal Coordinated EV Charging with Reactive Power Support in Constrained Distribution Grids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paudyal, Sumit; Ceylan, Oğuzhan; Bhattarai, Bishnu P.

Electric vehicle (EV) charging/discharging can take place in any P-Q quadrants, which means EVs could support reactive power to the grid while charging the battery. In controlled charging schemes, distribution system operator (DSO) coordinates with the charging of EV fleets to ensure grid’s operating constraints are not violated. In fact, this refers to DSO setting upper bounds on power limits for EV charging. In this work, we demonstrate that if EVs inject reactive power into the grid while charging, DSO could issue higher upper bounds on the active power limits for the EVs for the same set of grid constraints.more » We demonstrate the concept in an 33-node test feeder with 1,500 EVs. Case studies show that in constrained distribution grids in coordinated charging, average costs of EV charging could be reduced if the charging takes place in the fourth P-Q quadrant compared to charging with unity power factor.« less

Stochastic parameter estimation in nonlinear time-delayed vibratory systems with distributed delay

NASA Astrophysics Data System (ADS)

Torkamani, Shahab; Butcher, Eric A.

2013-07-01

The stochastic estimation of parameters and states in linear and nonlinear time-delayed vibratory systems with distributed delay is explored. The approach consists of first employing a continuous time approximation to approximate the delayed integro-differential system with a large set of ordinary differential equations having stochastic excitations. Then the problem of state and parameter estimation in the resulting stochastic ordinary differential system is represented as an optimal filtering problem using a state augmentation technique. By adapting the extended Kalman-Bucy filter to the augmented filtering problem, the unknown parameters of the time-delayed system are estimated from noise-corrupted, possibly incomplete measurements of the states. Similarly, the upper bound of the distributed delay can also be estimated by the proposed technique. As an illustrative example to a practical problem in vibrations, the parameter, delay upper bound, and state estimation from noise-corrupted measurements in a distributed force model widely used for modeling machine tool vibrations in the turning operation is investigated.

Performance Analysis of Amplify-and-Forward Systems with Single Relay Selection in Correlated Environments.

PubMed

Van Nguyen, Binh; Kim, Kiseon

2016-09-11

In this paper, we consider amplify-and-forward (AnF) cooperative systems under correlated fading environments. We first present a brief overview of existing works on the effect of channel correlations on the system performance. We then focus on our main contribution which is analyzing the outage probability of a multi-AnF-relay system with the best relay selection (BRS) scheme under a condition that two channels of each relay, source-relay and relay-destination channels, are correlated. Using lower and upper bounds on the end-to-end received signal-to-noise ratio (SNR) at the destination, we derive corresponding upper and lower bounds on the system outage probability. We prove that the system can achieve a diversity order (DO) equal to the number of relays. In addition, and importantly, we show that the considered correlation form has a constructive effect on the system performance. In other words, the larger the correlation coefficient, the better system performance. Our analytic results are corroborated by extensive Monte-Carlo simulations.

Beamforming Based Full-Duplex for Millimeter-Wave Communication

PubMed Central

Liu, Xiao; Xiao, Zhenyu; Bai, Lin; Choi, Jinho; Xia, Pengfei; Xia, Xiang-Gen

2016-01-01

In this paper, we study beamforming based full-duplex (FD) systems in millimeter-wave (mmWave) communications. A joint transmission and reception (Tx/Rx) beamforming problem is formulated to maximize the achievable rate by mitigating self-interference (SI). Since the optimal solution is difficult to find due to the non-convexity of the objective function, suboptimal schemes are proposed in this paper. A low-complexity algorithm, which iteratively maximizes signal power while suppressing SI, is proposed and its convergence is proven. Moreover, two closed-form solutions, which do not require iterations, are also derived under minimum-mean-square-error (MMSE), zero-forcing (ZF), and maximum-ratio transmission (MRT) criteria. Performance evaluations show that the proposed iterative scheme converges fast (within only two iterations on average) and approaches an upper-bound performance, while the two closed-form solutions also achieve appealing performances, although there are noticeable differences from the upper bound depending on channel conditions. Interestingly, these three schemes show different robustness against the geometry of Tx/Rx antenna arrays and channel estimation errors. PMID:27455256

White Light Stray Light Test of the SOHO UVCS

NASA Technical Reports Server (NTRS)

Gardner, L. N.; Gardner, L. N.; Fineschi, S.

1998-01-01

During the late stages of the integration phase of the Ultraviolet Coronagraph Spectrometer (UVCS) instrument for the Solar and Heliospheric Observatory (SOHO) at MATRA-Marconi in Toulouse, France, SOHO Project management at Goddard Space Flight Center (GSFC) became concerned that the elaborate stray light rejection system for the instrument had not been tested and might possibly be misaligned such that the instrument could not deliver promised scientific returns. A white light stray light test, which would place an upper bound on the value of UVCS's stray light rejection capability, was commissioned, conceived, and carried out. This upper bound value would be indicative of the weakest coronal features the spectrometer would be capable of discerning. The test was rapidly developed at GSFC in coordination with science team members from Harvard-Smithsonian Center for Astrophysics (CFA) and was carried out at MATRA in late February 1995. The outcome of this test helped to justify similar, much desired tests with visible and far ultraviolet light at CFA in a facility specifically designed to perform such testing.

Quantifying the tracking capability of space-based AIS systems

NASA Astrophysics Data System (ADS)

Skauen, Andreas Nordmo

2016-01-01

The Norwegian Defence Research Establishment (FFI) has operated three Automatic Identification System (AIS) receivers in space. Two are on dedicated nano-satellites, AISSat-1 and AISSat-2. The third, the NORAIS Receiver, was installed on the International Space Station. A general method for calculating the upper bound on the tracking capability of a space-based AIS system has been developed and the results from the algorithm applied to AISSat-1 and the NORAIS Receiver individually. In addition, a constellation of AISSat-1 and AISSat-2 is presented. The tracking capability is defined as the probability of re-detecting ships as they move around the globe and is explained to represent and upper bound on a space-based AIS system performance. AISSat-1 and AISSat-2 operates on the nominal AIS1 and AIS2 channels, while the NORAIS Receiver data used are from operations on the dedicated space AIS channels, AIS3 and AIS4. The improved tracking capability of operations on the space AIS channels is presented.

Flutter suppression and stability analysis for a variable-span wing via morphing technology

NASA Astrophysics Data System (ADS)

Li, Wencheng; Jin, Dongping

2018-01-01

A morphing wing can enhance aerodynamic characteristics and control authority as an alternative to using ailerons. To use morphing technology for flutter suppression, the dynamical behavior and stability of a variable-span wing subjected to the supersonic aerodynamic loads are investigated numerically in this paper. An axially moving cantilever plate is employed to model the variable-span wing, in which the governing equations of motion are established via the Kane method and piston theory. A morphing strategy based on axially moving rates is proposed to suppress the flutter that occurs beyond the critical span length, and the flutter stability is verified by Floquet theory. Furthermore, the transient stability during the morphing motion is analyzed and the upper bound of the morphing rate is obtained. The simulation results indicate that the proposed morphing law, which is varying periodically with a proper amplitude, could accomplish the flutter suppression. Further, the upper bound of the morphing speed decreases rapidly once the span length is close to its critical span length.

Activity of upper limb muscles during human walking.

PubMed

Kuhtz-Buschbeck, Johann P; Jing, Bo

2012-04-01

The EMG activity of upper limb muscles during human gait has rarely been studied previously. It was examined in 20 normal volunteers in four conditions: walking on a treadmill (1) with unrestrained natural arm swing (Normal), (2) while volitionally holding the arms still (Held), (3) with the arms immobilized (Bound), and (4) with the arms swinging in phase with the ipsilateral legs, i.e. opposite-to-normal phasing (Anti-Normal). Normal arm swing involved weak rhythmical lengthening and shortening contractions of arm and shoulder muscles. Phasic muscle activity was needed to keep the unrestricted arms still during walking (Held), indicating a passive component of arm swing. An active component, possibly programmed centrally, existed as well, because some EMG signals persisted when the arms were immobilized during walking (Bound). Anti-Normal gait involved stronger EMG activity than Normal walking and was uneconomical. The present results indicate that normal arm swing has both passive and active components. Copyright © 2011 Elsevier Ltd. All rights reserved.

Time-optical spinup maneuvers of flexible spacecraft

NASA Technical Reports Server (NTRS)

Singh, G.; Kabamba, P. T.; Mcclamroch, N. H.

1990-01-01

Attitude controllers for spacecraft have been based on the assumption that the bodies being controlled are rigid. Future spacecraft, however, may be quite flexible. Many applications require spinning up/down these vehicles. In this work the minimum time control of these maneuvers is considered. The time-optimal control is shown to possess an important symmetry property. Taking advantage of this property, the necessary and sufficient conditions for optimality are transformed into a system of nonlinear algebraic equations in the control switching times during one half of the maneuver, the maneuver time, and the costates at the mid-maneuver time. These equations can be solved using a homotopy approach. Control spillover measures are introduced and upper bounds on these measures are obtained. For a special case these upper bounds can be expressed in closed form for an infinite dimensional evaluation model. Rotational stiffening effects are ignored in the optimal control analysis. Based on a heuristic argument a simple condition is given which justifies the omission of these nonlinear effects. This condition is validated by numerical simulation.

Mercury: results on mass, radius, ionosphere, and atmosphere from mariner 10 dual-frequency radio signals.

PubMed

Howard, H T; Tyler, G L; Esposito, P B; Anderson, J D; Reasenberg, R D; Shapiro, I I; Fjeldbo, G; Kliore, A J; Levy, G S; Brunn, D L; Dickinson, R; Edelson, R E; Martin, W L; Postal, R B; Seidel, B; Sesplaukis, T T; Shirley, D L; Stelzried, C T; Sweetnam, D N; Wood, G E; Zygielbaum, A I

1974-07-12

Analysis of the radio-tracking data from Mariner 10 yields 6,023,600 +/- 600 for the ratio of the mass of the sun to that of Mercury, in very good agreement with values determined earlier from radar data alone. Occultation measurements yielded values for the radius of Mercury of 2440 +/- 2 and 2438 +/- 2 kilometers at laditudes of 2 degrees N and 68 degrees N, respectively, again in close agreement with the average equatorial radius of 2439 +/- 1 kilometers determined from radar data. The mean density of 5.44 grams per cubic centimeter deduced for Mercury from Mariner 10 data thus virtually coincides with the prior determination. No evidence of either an ionosphere or an atmosphere was found, with the data yielding upper bounds on the electron density of about 1500 and 4000 electrons per cubic centimeter on the dayside and nightside, respectively, and an inferred upper bound on the surface pressure of 10(-8) millibar.

Nonlinear recurrent neural networks for finite-time solution of general time-varying linear matrix equations.

PubMed

Xiao, Lin; Liao, Bolin; Li, Shuai; Chen, Ke

2018-02-01

In order to solve general time-varying linear matrix equations (LMEs) more efficiently, this paper proposes two nonlinear recurrent neural networks based on two nonlinear activation functions. According to Lyapunov theory, such two nonlinear recurrent neural networks are proved to be convergent within finite-time. Besides, by solving differential equation, the upper bounds of the finite convergence time are determined analytically. Compared with existing recurrent neural networks, the proposed two nonlinear recurrent neural networks have a better convergence property (i.e., the upper bound is lower), and thus the accurate solutions of general time-varying LMEs can be obtained with less time. At last, various different situations have been considered by setting different coefficient matrices of general time-varying LMEs and a great variety of computer simulations (including the application to robot manipulators) have been conducted to validate the better finite-time convergence of the proposed two nonlinear recurrent neural networks. Copyright © 2017 Elsevier Ltd. All rights reserved.

Two approximations of the present value distribution of a disability annuity

NASA Astrophysics Data System (ADS)

Spreeuw, Jaap

2006-02-01

The distribution function of the present value of a cash flow can be approximated by means of a distribution function of a random variable, which is also the present value of a sequence of payments, but with a simpler structure. The corresponding random variable has the same expectation as the random variable corresponding to the original distribution function and is a stochastic upper bound of convex order. A sharper upper bound can be obtained if more information about the risk is available. In this paper, it will be shown that such an approach can be adopted for disability annuities (also known as income protection policies) in a three state model under Markov assumptions. Benefits are payable during any spell of disability whilst premiums are only due whenever the insured is healthy. The quality of the two approximations is investigated by comparing the distributions obtained with the one derived from the algorithm presented in the paper by Hesselager and Norberg [Insurance Math. Econom. 18 (1996) 35-42].