Modelling of Non-Premixed Turbulent Combustion of Hydrogen using Conditional Moment Closure Method
International Nuclear Information System (INIS)
Noor, M M; Hairuddin, A Aziz; Wandel, Andrew P; Yusaf, T F
2012-01-01
Most of the electricity generation and energy for transport is still generated by the conversion of chemical to mechanical energy by burning the fuels in the combustion chamber. Regulation for pollution and the demand for more fuel economy had driven worldwide researcher to focus on combustion efficiency. In order to reduce experimental cost, accurate modelling and simulation is very critical step. Taylor series expansion was utilised to reduce the error term for the discretization. FORTRAN code was used to execute the discretized partial differential equation. Hydrogen combustion was simulated using Conditional Moment Closure (CMC) model. Combustion of hydrogen with oxygen was successfully simulated and reported in this paper.
The conditional moment closure method for modeling lean premixed turbulent combustion
Martin, Scott Montgomery
Natural gas fired lean premixed gas turbines have become the method of choice for new power generation systems due to their high efficiency and low pollutant emissions. As emission regulations for these combustion systems become more stringent, the use of numerical modeling has become an important a priori tool in designing clean and efficient combustors. Here a new turbulent combustion model is developed in an attempt to improve the state of the art. The Conditional Moment Closure (CMC) method is a new theory that has been applied to non-premixed combustion with good success. The application of the CMC method to premixed systems has been proposed, but has not yet been done. The premixed CMC method replaces the species mass fractions as independent variables with the species mass fractions that are conditioned on a reaction progress variable (RPV). Conservation equations for these new variables are then derived and solved. The general idea behind the CMC method is that the behavior of the chemical species is closely coupled to the reaction progress variable. Thus, species conservation equations that are conditioned on the RPV will have terms involving the fluctuating quantities that are much more likely to be negligible. The CMC method accounts for the interaction between scalar dissipation (micromixing) and chemistry, while de-coupling the kinetics from the bulk flow (macromixing). Here the CMC method is combined with a commercial computational fluid dynamics program, which calculates the large-scale fluid motions. The CMC model is validated by comparison to 2-D reacting backward facing step data. Predicted species, temperature and velocity fields are compared to experimental data with good success. The CMC model is also validated against the University of Washington's 3-D jet stirred reactor (JSR) data, which is an idealized lean premixed combustor. The JSR results are encouraging, but not as good as the backward facing step. The largest source of error is from
Moment Closure for the Stochastic Logistic Model
National Research Council Canada - National Science Library
Singh, Abhyudai; Hespanha, Joao P
2006-01-01
..., which we refer to as the moment closure function. In this paper, a systematic procedure for constructing moment closure functions of arbitrary order is presented for the stochastic logistic model...
Directory of Open Access Journals (Sweden)
Ahmad El Sayed
2015-01-01
Full Text Available A lifted hydrogen/nitrogen turbulent jet flame issuing into a vitiated coflow is investigated using the conditional moment closure (CMC supplemented by the presumed mapping function (PMF approach for the modelling of conditional mixing and velocity statistics. Using a prescribed reference field, the PMF approach yields a presumed probability density function (PDF for the mixture fraction, which is then used in closing the conditional scalar dissipation rate (CSDR and conditional velocity in a fully consistent manner. These closures are applied to a lifted flame and the findings are compared to previous results obtained using β-PDF-based closures over a range of coflow temperatures (Tc. The PMF results are in line with those of the β-PDF and compare well to measurements. The transport budgets in mixture fraction and physical spaces and the radical history ahead of the stabilisation height indicate that the stabilisation mechanism is susceptible to Tc. As in the previous β-PDF calculations, autoignition around the “most reactive” mixture fraction remains the controlling mechanism for sufficiently high Tc. Departure from the β-PDF predictions is observed when Tc is decreased as PMF predicts stabilisation by means of premixed flame propagation. This conclusion is based on the observation that lean mixtures are heated by downstream burning mixtures in a preheat zone developing ahead of the stabilization height. The spurious sources, which stem from inconsistent CSDR modelling, are further investigated. The findings reveal that their effect is small but nonnegligible, most notably within the flame zone.
Numerical approximation of the Boltzmann equation : moment closure
Abdel Malik, M.R.A.; Brummelen, van E.H.
2012-01-01
This work applies the moment method onto a generic form of kinetic equations to simplify kinetic models of particle systems. This leads to the moment closure problem which is addressed using entropy-based moment closure techniques utilizing entropy minimization. The resulting moment closure system
Comparison of PDF and Moment Closure Methods in the Modeling of Turbulent Reacting Flows
Norris, Andrew T.; Hsu, Andrew T.
1994-01-01
In modeling turbulent reactive flows, Probability Density Function (PDF) methods have an advantage over the more traditional moment closure schemes in that the PDF formulation treats the chemical reaction source terms exactly, while moment closure methods are required to model the mean reaction rate. The common model used is the laminar chemistry approximation, where the effects of turbulence on the reaction are assumed negligible. For flows with low turbulence levels and fast chemistry, the difference between the two methods can be expected to be small. However for flows with finite rate chemistry and high turbulence levels, significant errors can be expected in the moment closure method. In this paper, the ability of the PDF method and the moment closure scheme to accurately model a turbulent reacting flow is tested. To accomplish this, both schemes were used to model a CO/H2/N2- air piloted diffusion flame near extinction. Identical thermochemistry, turbulence models, initial conditions and boundary conditions are employed to ensure a consistent comparison can be made. The results of the two methods are compared to experimental data as well as to each other. The comparison reveals that the PDF method provides good agreement with the experimental data, while the moment closure scheme incorrectly shows a broad, laminar-like flame structure.
Multivariate moment closure techniques for stochastic kinetic models
International Nuclear Information System (INIS)
Lakatos, Eszter; Ale, Angelique; Kirk, Paul D. W.; Stumpf, Michael P. H.
2015-01-01
Stochastic effects dominate many chemical and biochemical processes. Their analysis, however, can be computationally prohibitively expensive and a range of approximation schemes have been proposed to lighten the computational burden. These, notably the increasingly popular linear noise approximation and the more general moment expansion methods, perform well for many dynamical regimes, especially linear systems. At higher levels of nonlinearity, it comes to an interplay between the nonlinearities and the stochastic dynamics, which is much harder to capture correctly by such approximations to the true stochastic processes. Moment-closure approaches promise to address this problem by capturing higher-order terms of the temporally evolving probability distribution. Here, we develop a set of multivariate moment-closures that allows us to describe the stochastic dynamics of nonlinear systems. Multivariate closure captures the way that correlations between different molecular species, induced by the reaction dynamics, interact with stochastic effects. We use multivariate Gaussian, gamma, and lognormal closure and illustrate their use in the context of two models that have proved challenging to the previous attempts at approximating stochastic dynamics: oscillations in p53 and Hes1. In addition, we consider a larger system, Erk-mediated mitogen-activated protein kinases signalling, where conventional stochastic simulation approaches incur unacceptably high computational costs
Multivariate moment closure techniques for stochastic kinetic models
Energy Technology Data Exchange (ETDEWEB)
Lakatos, Eszter, E-mail: e.lakatos13@imperial.ac.uk; Ale, Angelique; Kirk, Paul D. W.; Stumpf, Michael P. H., E-mail: m.stumpf@imperial.ac.uk [Department of Life Sciences, Centre for Integrative Systems Biology and Bioinformatics, Imperial College London, London SW7 2AZ (United Kingdom)
2015-09-07
Stochastic effects dominate many chemical and biochemical processes. Their analysis, however, can be computationally prohibitively expensive and a range of approximation schemes have been proposed to lighten the computational burden. These, notably the increasingly popular linear noise approximation and the more general moment expansion methods, perform well for many dynamical regimes, especially linear systems. At higher levels of nonlinearity, it comes to an interplay between the nonlinearities and the stochastic dynamics, which is much harder to capture correctly by such approximations to the true stochastic processes. Moment-closure approaches promise to address this problem by capturing higher-order terms of the temporally evolving probability distribution. Here, we develop a set of multivariate moment-closures that allows us to describe the stochastic dynamics of nonlinear systems. Multivariate closure captures the way that correlations between different molecular species, induced by the reaction dynamics, interact with stochastic effects. We use multivariate Gaussian, gamma, and lognormal closure and illustrate their use in the context of two models that have proved challenging to the previous attempts at approximating stochastic dynamics: oscillations in p53 and Hes1. In addition, we consider a larger system, Erk-mediated mitogen-activated protein kinases signalling, where conventional stochastic simulation approaches incur unacceptably high computational costs.
Analysis of turbulent conical diffuser flow using second moment closures
International Nuclear Information System (INIS)
Adane, K.K.; Tachie, M.F.; Ormiston, S.J.
2004-01-01
A commercial CFD code, CFX-TASCflow, is used to predict a turbulent conical diffuser flow. The computation was performed using a low-Reynolds number k-ω model, a low-Reynolds number k-ω based non-linear algebraic Reynolds stress model, and a second moment closure with a wall-function. The experimental data of Kassab are used to validate the numerical results. The results show that all the turbulence models reproduce the static pressure coefficient distribution reasonably well. The low Reynolds number k-ω models give better prediction of the friction velocity than the second moment closure. The models also predict the Reynolds shear stress reasonably well but fail to reproduce the correct level of the turbulent kinetic energy. (author)
International Nuclear Information System (INIS)
Myong, R. S.; Nagdewe, S. P.
2011-01-01
The Grad's closure for the high-order moment equation is revisited and, by extending his theory, a physically motivated closure is developed for the one-dimensional velocity shear gas flow. The closure is based on the physical argument of the relative importance of various terms appearing in the moment equation. Also, the closure is derived such that the resulting theory may be inclusive of the well established linear theory (Navier-Stokes-Fourier) as limiting case near local thermal equilibrium.
Defining Higher-Order Turbulent Moment Closures with an Artificial Neural Network and Random Forest
McGibbon, J.; Bretherton, C. S.
2017-12-01
Unresolved turbulent advection and clouds must be parameterized in atmospheric models. Modern higher-order closure schemes depend on analytic moment closure assumptions that diagnose higher-order moments in terms of lower-order ones. These are then tested against Large-Eddy Simulation (LES) higher-order moment relations. However, these relations may not be neatly analytic in nature. Rather than rely on an analytic higher-order moment closure, can we use machine learning on LES data itself to define a higher-order moment closure?We assess the ability of a deep artificial neural network (NN) and random forest (RF) to perform this task using a set of observationally-based LES runs from the MAGIC field campaign. By training on a subset of 12 simulations and testing on remaining simulations, we avoid over-fitting the training data.Performance of the NN and RF will be assessed and compared to the Analytic Double Gaussian 1 (ADG1) closure assumed by Cloudy Layers Unified By Binormals (CLUBB), a higher-order turbulence closure currently used in the Community Atmosphere Model (CAM). We will show that the RF outperforms the NN and the ADG1 closure for the MAGIC cases within this diagnostic framework. Progress and challenges in using a diagnostic machine learning closure within a prognostic cloud and turbulence parameterization will also be discussed.
Flow simulation in piping system dead legs using second moment, closure and k-epsilon model
International Nuclear Information System (INIS)
Deutsch, E.; Mechitoua, N.; Mattei, J.D.
1996-01-01
This paper deals with an industrial application of second moment closure turbulence model in in numerical simulation of 3D turbulent flows in piping system dead legs. Calculations performed with the 3D ESTET code are presented which contrast the performance of k-epsilon eddy viscosity model and second moment closure turbulence models. Coarse (100 000), medium (400 000) and fine (1 500 000) meshes were used. The second moment closure performs significantly better than eddy viscosity model and predicts with a good agreement the vortex penetration in dead legs provided to use sufficiently refined meshes. The results point out the necessity to be able to perform calculations using fine mesh before introducing refined physical models such as second moment closure turbulence model in a numerical code. This study illustrates the ability of second moment closure turbulence model to simulate 3D turbulent industrial flows. Reynolds stress model computation does not require special care, the calculation is carried on as simply as the k-ξ one. The CPU time needed is less that twice the CPU time needed using k-ξ model. (authors)
Foucart, Francois
2018-04-01
General relativistic radiation hydrodynamic simulations are necessary to accurately model a number of astrophysical systems involving black holes and neutron stars. Photon transport plays a crucial role in radiatively dominated accretion discs, while neutrino transport is critical to core-collapse supernovae and to the modelling of electromagnetic transients and nucleosynthesis in neutron star mergers. However, evolving the full Boltzmann equations of radiative transport is extremely expensive. Here, we describe the implementation in the general relativistic SPEC code of a cheaper radiation hydrodynamic method that theoretically converges to a solution of Boltzmann's equation in the limit of infinite numerical resources. The algorithm is based on a grey two-moment scheme, in which we evolve the energy density and momentum density of the radiation. Two-moment schemes require a closure that fills in missing information about the energy spectrum and higher order moments of the radiation. Instead of the approximate analytical closure currently used in core-collapse and merger simulations, we complement the two-moment scheme with a low-accuracy Monte Carlo evolution. The Monte Carlo results can provide any or all of the missing information in the evolution of the moments, as desired by the user. As a first test of our methods, we study a set of idealized problems demonstrating that our algorithm performs significantly better than existing analytical closures. We also discuss the current limitations of our method, in particular open questions regarding the stability of the fully coupled scheme.
Efficient algorithms and implementations of entropy-based moment closures for rarefied gases
Energy Technology Data Exchange (ETDEWEB)
Schaerer, Roman Pascal, E-mail: schaerer@mathcces.rwth-aachen.de; Bansal, Pratyuksh; Torrilhon, Manuel
2017-07-01
We present efficient algorithms and implementations of the 35-moment system equipped with the maximum-entropy closure in the context of rarefied gases. While closures based on the principle of entropy maximization have been shown to yield very promising results for moderately rarefied gas flows, the computational cost of these closures is in general much higher than for closure theories with explicit closed-form expressions of the closing fluxes, such as Grad's classical closure. Following a similar approach as Garrett et al. (2015) , we investigate efficient implementations of the computationally expensive numerical quadrature method used for the moment evaluations of the maximum-entropy distribution by exploiting its inherent fine-grained parallelism with the parallelism offered by multi-core processors and graphics cards. We show that using a single graphics card as an accelerator allows speed-ups of two orders of magnitude when compared to a serial CPU implementation. To accelerate the time-to-solution for steady-state problems, we propose a new semi-implicit time discretization scheme. The resulting nonlinear system of equations is solved with a Newton type method in the Lagrange multipliers of the dual optimization problem in order to reduce the computational cost. Additionally, fully explicit time-stepping schemes of first and second order accuracy are presented. We investigate the accuracy and efficiency of the numerical schemes for several numerical test cases, including a steady-state shock-structure problem.
Efficient algorithms and implementations of entropy-based moment closures for rarefied gases
International Nuclear Information System (INIS)
Schaerer, Roman Pascal; Bansal, Pratyuksh; Torrilhon, Manuel
2017-01-01
We present efficient algorithms and implementations of the 35-moment system equipped with the maximum-entropy closure in the context of rarefied gases. While closures based on the principle of entropy maximization have been shown to yield very promising results for moderately rarefied gas flows, the computational cost of these closures is in general much higher than for closure theories with explicit closed-form expressions of the closing fluxes, such as Grad's classical closure. Following a similar approach as Garrett et al. (2015) , we investigate efficient implementations of the computationally expensive numerical quadrature method used for the moment evaluations of the maximum-entropy distribution by exploiting its inherent fine-grained parallelism with the parallelism offered by multi-core processors and graphics cards. We show that using a single graphics card as an accelerator allows speed-ups of two orders of magnitude when compared to a serial CPU implementation. To accelerate the time-to-solution for steady-state problems, we propose a new semi-implicit time discretization scheme. The resulting nonlinear system of equations is solved with a Newton type method in the Lagrange multipliers of the dual optimization problem in order to reduce the computational cost. Additionally, fully explicit time-stepping schemes of first and second order accuracy are presented. We investigate the accuracy and efficiency of the numerical schemes for several numerical test cases, including a steady-state shock-structure problem.
Efficient algorithms and implementations of entropy-based moment closures for rarefied gases
Schaerer, Roman Pascal; Bansal, Pratyuksh; Torrilhon, Manuel
2017-07-01
We present efficient algorithms and implementations of the 35-moment system equipped with the maximum-entropy closure in the context of rarefied gases. While closures based on the principle of entropy maximization have been shown to yield very promising results for moderately rarefied gas flows, the computational cost of these closures is in general much higher than for closure theories with explicit closed-form expressions of the closing fluxes, such as Grad's classical closure. Following a similar approach as Garrett et al. (2015) [13], we investigate efficient implementations of the computationally expensive numerical quadrature method used for the moment evaluations of the maximum-entropy distribution by exploiting its inherent fine-grained parallelism with the parallelism offered by multi-core processors and graphics cards. We show that using a single graphics card as an accelerator allows speed-ups of two orders of magnitude when compared to a serial CPU implementation. To accelerate the time-to-solution for steady-state problems, we propose a new semi-implicit time discretization scheme. The resulting nonlinear system of equations is solved with a Newton type method in the Lagrange multipliers of the dual optimization problem in order to reduce the computational cost. Additionally, fully explicit time-stepping schemes of first and second order accuracy are presented. We investigate the accuracy and efficiency of the numerical schemes for several numerical test cases, including a steady-state shock-structure problem.
Comparison of different moment-closure approximations for stochastic chemical kinetics
Energy Technology Data Exchange (ETDEWEB)
Schnoerr, David [School of Biological Sciences, University of Edinburgh, Edinburgh (United Kingdom); School of Informatics, University of Edinburgh, Edinburgh (United Kingdom); Sanguinetti, Guido [School of Informatics, University of Edinburgh, Edinburgh (United Kingdom); Grima, Ramon [School of Biological Sciences, University of Edinburgh, Edinburgh (United Kingdom)
2015-11-14
In recent years, moment-closure approximations (MAs) of the chemical master equation have become a popular method for the study of stochastic effects in chemical reaction systems. Several different MA methods have been proposed and applied in the literature, but it remains unclear how they perform with respect to each other. In this paper, we study the normal, Poisson, log-normal, and central-moment-neglect MAs by applying them to understand the stochastic properties of chemical systems whose deterministic rate equations show the properties of bistability, ultrasensitivity, and oscillatory behaviour. Our results suggest that the normal MA is favourable over the other studied MAs. In particular, we found that (i) the size of the region of parameter space where a closure gives physically meaningful results, e.g., positive mean and variance, is considerably larger for the normal closure than for the other three closures, (ii) the accuracy of the predictions of the four closures (relative to simulations using the stochastic simulation algorithm) is comparable in those regions of parameter space where all closures give physically meaningful results, and (iii) the Poisson and log-normal MAs are not uniquely defined for systems involving conservation laws in molecule numbers. We also describe the new software package MOCA which enables the automated numerical analysis of various MA methods in a graphical user interface and which was used to perform the comparative analysis presented in this paper. MOCA allows the user to develop novel closure methods and can treat polynomial, non-polynomial, as well as time-dependent propensity functions, thus being applicable to virtually any chemical reaction system.
Bronstein, Leo; Koeppl, Heinz
2018-01-01
Approximate solutions of the chemical master equation and the chemical Fokker-Planck equation are an important tool in the analysis of biomolecular reaction networks. Previous studies have highlighted a number of problems with the moment-closure approach used to obtain such approximations, calling it an ad hoc method. In this article, we give a new variational derivation of moment-closure equations which provides us with an intuitive understanding of their properties and failure modes and allows us to correct some of these problems. We use mixtures of product-Poisson distributions to obtain a flexible parametric family which solves the commonly observed problem of divergences at low system sizes. We also extend the recently introduced entropic matching approach to arbitrary ansatz distributions and Markov processes, demonstrating that it is a special case of variational moment closure. This provides us with a particularly principled approximation method. Finally, we extend the above approaches to cover the approximation of multi-time joint distributions, resulting in a viable alternative to process-level approximations which are often intractable.
Optimization and large scale computation of an entropy-based moment closure
Kristopher Garrett, C.; Hauck, Cory; Hill, Judith
2015-12-01
We present computational advances and results in the implementation of an entropy-based moment closure, MN, in the context of linear kinetic equations, with an emphasis on heterogeneous and large-scale computing platforms. Entropy-based closures are known in several cases to yield more accurate results than closures based on standard spectral approximations, such as PN, but the computational cost is generally much higher and often prohibitive. Several optimizations are introduced to improve the performance of entropy-based algorithms over previous implementations. These optimizations include the use of GPU acceleration and the exploitation of the mathematical properties of spherical harmonics, which are used as test functions in the moment formulation. To test the emerging high-performance computing paradigm of communication bound simulations, we present timing results at the largest computational scales currently available. These results show, in particular, load balancing issues in scaling the MN algorithm that do not appear for the PN algorithm. We also observe that in weak scaling tests, the ratio in time to solution of MN to PN decreases.
A Necessary Moment Condition for the Fractional Central Limit Theorem
DEFF Research Database (Denmark)
Johansen, Søren; Nielsen, Morten
2012-01-01
We discuss the moment condition for the fractional functional central limit theorem (FCLT) for partial sums of x(t)=¿^{-d}u(t) , where -1/2classical condition is existence of q=2 and q>1/(d+1/2) moments...... of the innovation sequence. When d is close to -1/2 this moment condition is very strong. Our main result is to show that when -1/2conditions on u(t), the existence of q=1/(d+1/2) moments is in fact necessary for the FCLT for fractionally integrated processes and that q>1/(d+1....../2) moments are necessary for more general fractional processes. Davidson and de Jong (2000, Econometric Theory 16, 643-- 666) presented a fractional FCLT where onlyq>2 finite moments are assumed. As a corollary to our main theorem we show that their moment condition is not sufficient and hence...
Modelling turbulence around and inside porous media based on the second moment closure
International Nuclear Information System (INIS)
Kuwata, Yusuke; Suga, Kazuhiko
2013-01-01
Highlights: • A novel turbulence model for flows in porous media is proposed. • Three stress tensors emerging in double averaging N–S are individually modelled. • The most advanced second moment closure is applied for the macro-scale stress. • A one equation and the Smagorinsky models are applied to the other stresses. • Promising results are obtained in test flows around and inside porous media. -- Abstract: To predict turbulence in porous media, a new approach is discussed. By double (both volume and Reynolds) averaging Navier–Stokes equations, there appear three unknown covariant terms in the momentum equation. They are namely the dispersive covariance, the macro-scale and the micro-scale Reynolds stresses, in the present study. For the macro-scale Reynolds stress, the TCL (two-component-limit) second moment closure is applied whereas the eddy viscosity models are applied to the other covariant terms: the Smagorinsky model and the one-equation eddy viscosity model, respectively for the dispersive covariance and the micro-scale Reynolds stress. The presently proposed model is evaluated in square rib array flows and porous wall channel flows with reasonable accuracy though further development is required
Hamiltonian fluid closures of the Vlasov-Ampère equations: From water-bags to N moment models
Energy Technology Data Exchange (ETDEWEB)
Perin, M.; Chandre, C.; Tassi, E. [Aix-Marseille Université, Université de Toulon, CNRS, CPT UMR 7332, 13288 Marseille (France); Morrison, P. J. [Department of Physics and Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712-1060 (United States)
2015-09-15
Moment closures of the Vlasov-Ampère system, whereby higher moments are represented as functions of lower moments with the constraint that the resulting fluid system remains Hamiltonian, are investigated by using water-bag theory. The link between the water-bag formalism and fluid models that involve density, fluid velocity, pressure and higher moments is established by introducing suitable thermodynamic variables. The cases of one, two, and three water-bags are treated and their Hamiltonian structures are provided. In each case, we give the associated fluid closures and we discuss their Casimir invariants. We show how the method can be extended to an arbitrary number of fields, i.e., an arbitrary number of water-bags and associated moments. The thermodynamic interpretation of the resulting models is discussed. Finally, a general procedure to derive Hamiltonian N-field fluid models is proposed.
Thielen, L.; Hanjalić, K.; Jonker, H.; Manceau, R.
2005-01-01
We present numerical computations of flow and heat transfer in multiple jets impinging normally on a flat heated surface, obtained with a new second-moment turbulence closure combined with an elliptic blending model of non-viscous wall blocking effect. This model provides the mean velocity and
International Nuclear Information System (INIS)
Nishimura, M.; Maekawa, I.
2004-01-01
A numerical study is performed on the natural draft reactor cavity cooling system (RCCS). In the cooling system, buoyancy driven heated upward flow could be in the mixed convection regime that is accompanied by heat transfer impairment. Also, the heating wall condition is asymmetric with regard to the channel cross section. These flow regime and thermal boundary conditions may invalidate the use of design correlation. To precisely simulate the flow and thermal fields within the RCCS, the second moment closure turbulence model is applied. Two types of the RCCS channel geometry are selected to make a comparison: an annular duct with fins on the outer surface of the inner circular wall, and a multi-rectangular duct. The prediction shows that the local heat transfer coefficient on the RCCS with finned annular duct is less than 1/6 of that estimated with Dittus-Boelter correlation. Much portion of the natural draft airflow does not contribute cooling at all because mainstream escapes from the narrow gaps between the fins. This result and thus the finned annulus design are unacceptable from the viewpoint for structural integrity of the RCCS wall boundary. The performance of the multi-rectangular duct design is acceptable that the RCCS maximum temperature is less than 400 degree centigrade even when the flow rate is halved from the designed condition. (author)
Roy, Subrata P.
2014-01-28
The method of moments with interpolative closure (MOMIC) for soot formation and growth provides a detailed modeling framework maintaining a good balance in generality, accuracy, robustness, and computational efficiency. This study presents several computational issues in the development and implementation of the MOMIC-based soot modeling for direct numerical simulations (DNS). The issues of concern include a wide dynamic range of numbers, choice of normalization, high effective Schmidt number of soot particles, and realizability of the soot particle size distribution function (PSDF). These problems are not unique to DNS, but they are often exacerbated by the high-order numerical schemes used in DNS. Four specific issues are discussed in this article: the treatment of soot diffusion, choice of interpolation scheme for MOMIC, an approach to deal with strongly oxidizing environments, and realizability of the PSDF. General, robust, and stable approaches are sought to address these issues, minimizing the use of ad hoc treatments such as clipping. The solutions proposed and demonstrated here are being applied to generate new physical insight into complex turbulence-chemistry-soot-radiation interactions in turbulent reacting flows using DNS. © 2014 Copyright Taylor and Francis Group, LLC.
Moment Conditions Selection Based on Adaptive Penalized Empirical Likelihood
Directory of Open Access Journals (Sweden)
Yunquan Song
2014-01-01
Full Text Available Empirical likelihood is a very popular method and has been widely used in the fields of artificial intelligence (AI and data mining as tablets and mobile application and social media dominate the technology landscape. This paper proposes an empirical likelihood shrinkage method to efficiently estimate unknown parameters and select correct moment conditions simultaneously, when the model is defined by moment restrictions in which some are possibly misspecified. We show that our method enjoys oracle-like properties; that is, it consistently selects the correct moment conditions and at the same time its estimator is as efficient as the empirical likelihood estimator obtained by all correct moment conditions. Moreover, unlike the GMM, our proposed method allows us to carry out confidence regions for the parameters included in the model without estimating the covariances of the estimators. For empirical implementation, we provide some data-driven procedures for selecting the tuning parameter of the penalty function. The simulation results show that the method works remarkably well in terms of correct moment selection and the finite sample properties of the estimators. Also, a real-life example is carried out to illustrate the new methodology.
International Nuclear Information System (INIS)
Maupu, V.; Laurence, D.
1996-01-01
Natural turbulent convection in a differentially heated infinite vertical slot is computed with a mixed finite differences/Fourier code. At a Rayleigh number of 10 5 , in the case without mean stratification, periodic perturbations from the laminar solution develop and transition to a fully turbulent flow occurs. From then on, a database of one-point statistics is presented: mean velocity and temperature, Reynolds stress components, turbulent heat fluxes and variance of temperature, but also budgets of second moment equations. This database is then used for testing of a second moment closure based on the Launder-Reece-Rodi model on an elliptic relaxation for near wall effects on pressure redistribution. This level of modelling is required by the presence of counter gradient fluxes, which cannot be accounted for eddy viscosity and eddy diffusivity assumptions. Furthermore, an algebraic third order moment closure was found necessary because of counter gradient turbulent transport terms which appear to mainly originate from the mean velocity and temperature gradient terms usually neglected in conventional transport models, such as the standard Daly-Harlow or Hanjalic-Launder models. (authors)
International Nuclear Information System (INIS)
Pot, G.; Laurence, D.; Rharif, N.E.; Leal de Sousa, L.; Compe, C.
1995-12-01
This paper deals with the introduction of a second moment closure turbulence model (Reynolds Stress Model) in an industrial finite element code, N3S, developed at Electricite de France.The numerical implementation of the model in N3S will be detailed in 2D and 3D. Some details are given concerning finite element computations and solvers. Then, some results will be given, including a comparison between standard k-ε model, R.S.M. model and experimental data for some test case. (authors). 22 refs., 3 figs
International Nuclear Information System (INIS)
Maupu, V.; Laurence, D.; Boudjemadi, R.; Le Quere, P.
1996-03-01
Natural turbulent convection in a differentially heated infinite vertical slot is computed with a mixed finite differences/Fourier code. At a Rayleigh number of 10 5 , periodic perturbations from the laminar solution develop and transition to a fully turbulent flow occurs. From then on, a database of high order correlations is constituted and used for testing a second moment closure based on the LRR model and elliptic relaxation near wall effects. Counter gradient turbulent transport, found in the central part of the channel, requires an algebraic model for the triple correlations instead of the standard DH or HL, gradient diffusion models. (authors). 18 refs., 14 figs., 1 tab
Relativistic correction to the deuteron magnetic moment and angular condition
International Nuclear Information System (INIS)
Kondratyuk, L.A.; Strikman, M.I.
1983-01-01
The relativistic correction (RC) to the deuteron magnetic moment μsub(d) is investigated using the light-cone dynamics. The restrictions imposed by the angular condition on the electromagnetic current operator of deuteron are discussed in detail. It is shown that the additive model for the current operator of interacting consistuencies is consistent with the angular condition only for the two first terms of expansion of the ''good'' electromagnetic current component jsub(+) in powers of the momentum transfer q. The RC into μsub(d) is calculated using the mattix element of the ''good'' component. The account of RC decreases essentially the discrepancy between the theoretical and experimental values. The value of Δsub(μ) is determined for the Hamada-Johnston potential hard core potential (0.93x10 -2 ) for the Reid soft core potential (0.71x10 -2 ) and for the Paris potential (0.63x10 -2 )
A well-balanced scheme for Ten-Moment Gaussian closure equations with source term
Meena, Asha Kumari; Kumar, Harish
2018-02-01
In this article, we consider the Ten-Moment equations with source term, which occurs in many applications related to plasma flows. We present a well-balanced second-order finite volume scheme. The scheme is well-balanced for general equation of state, provided we can write the hydrostatic solution as a function of the space variables. This is achieved by combining hydrostatic reconstruction with contact preserving, consistent numerical flux, and appropriate source discretization. Several numerical experiments are presented to demonstrate the well-balanced property and resulting accuracy of the proposed scheme.
Frasca, Mattia; Sharkey, Kieran J
2016-06-21
Understanding the dynamics of spread of infectious diseases between individuals is essential for forecasting the evolution of an epidemic outbreak or for defining intervention policies. The problem is addressed by many approaches including stochastic and deterministic models formulated at diverse scales (individuals, populations) and different levels of detail. Here we consider discrete-time SIR (susceptible-infectious-removed) dynamics propagated on contact networks. We derive a novel set of 'discrete-time moment equations' for the probability of the system states at the level of individual nodes and pairs of nodes. These equations form a set which we close by introducing appropriate approximations of the joint probabilities appearing in them. For the example case of SIR processes, we formulate two types of model, one assuming statistical independence at the level of individuals and one at the level of pairs. From the pair-based model we then derive a model at the level of the population which captures the behavior of epidemics on homogeneous random networks. With respect to their continuous-time counterparts, the models include a larger number of possible transitions from one state to another and joint probabilities with a larger number of individuals. The approach is validated through numerical simulation over different network topologies. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Directory of Open Access Journals (Sweden)
Gökhan Gökdere
2014-05-01
Full Text Available In this paper, closed form expressions for the moments of the truncated Pareto order statistics are obtained by using conditional distribution. We also derive some results for the moments which will be useful for moment computations based on ordered data.
Fisher, A. W.; Sanford, L. P.; Scully, M. E.
2016-12-01
Coherent wave-driven turbulence generated through wave breaking or nonlinear wave-current interactions, e.g. Langmuir turbulence (LT), can significantly enhance the downward transfer of momentum, kinetic energy, and dissolved gases in the oceanic surface layer. There are few observations of these processes in the estuarine or coastal environments, where wind-driven mixing may co-occur with energetic tidal mixing and strong density stratification. This presents a major challenge for evaluating vertical mixing parameterizations used in modeling estuarine and coastal dynamics. We carried out a large, multi-investigator study of wind-driven estuarine dynamics in the middle reaches of Chesapeake Bay, USA, during 2012-2013. The center of the observational array was an instrumented turbulence tower with both atmospheric and marine turbulence sensors as well as rapidly sampled temperature and conductivity sensors. For this paper, we examined the impacts of surface gravity waves on vertical profiles of turbulent mixing and compared our results to second-moment turbulence closure predictions. Wave and turbulence measurements collected from the vertical array of Acoustic Doppler Velocimeters (ADVs) provided direct estimates of the dominant terms in the TKE budget and the surface wave field. Observed dissipation rates, TKE levels, and turbulent length scales are compared to published scaling relations and used in the calculation of second-moment nonequilibrium stability functions. Results indicate that in the surface layer of the estuary, where elevated dissipation is balanced by vertical divergence in TKE flux, existing nonequilibrium stability functions underpredict observed eddy viscosities. The influences of wave breaking and coherent wave-driven turbulence on modeled and observed stability functions will be discussed further in the context of turbulent length scales, TKE and dissipation profiles, and the depth at which the wave-dominated turbulent transport layer
International Nuclear Information System (INIS)
Shin, Jong Keun; Choi, Young Don; An, Jeong Soo
2007-01-01
A second moment turbulence closure using the elliptic-blending equation is introduced to analyze the turbulence and heat transfer in a square sectioned U-bend duct flow. The turbulent heat flux model based on the elliptic concept satisfies the near-wall balance between viscous diffusion, viscous dissipation and temperature-pressure gradient correlation, and also has the characteristics of approaching its respective conventional high Reynolds number model far away from the wall. Also, the traditional GGDH heat flux model is compared with the present elliptic concept-based heat flux model. The turbulent heat flux models are closely linked to the elliptic blending second moment closure which is used for the prediction of Reynolds stresses. The predicted results show their reasonable agreement with experimental data for a square sectioned U-bend duct flow field adopted in the present study
Moment-based boundary conditions for lattice Boltzmann simulations of natural convection in cavities
Allen, Rebecca; Reis, Tim
2016-01-01
moments, which are then translated into conditions for the discrete velocity distribution functions. The method is formulated so that it is consistent with the second order implementation of the discrete velocity Boltzmann equations for fluid flow
A Necessary Moment Condition for the Fractional Functional Central Limit Theorem
DEFF Research Database (Denmark)
Johansen, Søren; Nielsen, Morten Ørregaard
We discuss the moment condition for the fractional functional central limit theorem (FCLT) for partial sums of x(t)=¿^(-d)u(t), where d ¿ (-1/2,1/2) is the fractional integration parameter and u(t) is weakly dependent. The classical condition is existence of q>max(2,(d+1/2)-¹) moments...... of the innovation sequence. When d is close to -1/2 this moment condition is very strong. Our main result is to show that under some relatively weak conditions on u(t), the existence of q=max(2,(d+1/2)-¹) is in fact necessary for the FCLT for fractionally integrated processes and that q>max(2,(d+1/2)-¹) moments...... are necessary and sufficient for more general fractional processes. Davidson and de Jong (2000) presented a fractional FCLT where only q>2 finite moments are assumed, which is remarkable because it is the only FCLT where the moment condition has been weakened relative to the earlier condition. As a corollary...
A necessary moment condition for the fractional functional central limit theorem
DEFF Research Database (Denmark)
Johansen, Søren; Nielsen, Morten Ørregaard
We discuss the moment condition for the fractional functional central limit theorem (FCLT) for partial sums of x_{t}=Delta^{-d}u_{t}, where d in (-1/2,1/2) is the fractional integration parameter and u_{t} is weakly dependent. The classical condition is existence of q>max(2,(d+1/2)^{-1}) moments...... of the innovation sequence. When d is close to -1/2 this moment condition is very strong. Our main result is to show that under some relatively weak conditions on u_{t}, the existence of q≥max(2,(d+1/2)^{-1}) is in fact necessary for the FCLT for fractionally integrated processes and that q>max(2,(d+1....../2)^{-1}) moments are necessary and sufficient for more general fractional processes. Davidson and de Jong (2000) presented a fractional FCLT where only q>2 finite moments are assumed, which is remarkable because it is the only FCLT where the moment condition has been weakened relative to the earlier condition...
Field-scale water balance closure in seasonally frozen conditions
Directory of Open Access Journals (Sweden)
X. Pan
2017-11-01
Full Text Available Hydrological water balance closure is a simple concept, yet in practice it is uncommon to measure every significant term independently in the field. Here we demonstrate the degree to which the field-scale water balance can be closed using only routine field observations in a seasonally frozen prairie pasture field site in Saskatchewan, Canada. Arrays of snow and soil moisture measurements were combined with a precipitation gauge and flux tower evapotranspiration estimates. We consider three hydrologically distinct periods: the snow accumulation period over the winter, the snowmelt period in spring, and the summer growing season. In each period, we attempt to quantify the residual between net precipitation (precipitation minus evaporation and the change in field-scale storage (snow and soil moisture, while accounting for measurement uncertainties. When the residual is negligible, a simple 1-D water balance with no net drainage is adequate. When the residual is non-negligible, we must find additional processes to explain the result. We identify the hydrological fluxes which confound the 1-D water balance assumptions during different periods of the year, notably blowing snow and frozen soil moisture redistribution during the snow accumulation period, and snowmelt runoff and soil drainage during the melt period. Challenges associated with quantifying these processes, as well as uncertainties in the measurable quantities, caution against the common use of water balance residuals to estimate fluxes and constrain models in such a complex environment.
Directory of Open Access Journals (Sweden)
Qunying Wu
2017-05-01
Full Text Available Abstract In this paper, we study the equivalent conditions of complete moment convergence for sequences of identically distributed extended negatively dependent random variables. As a result, we extend and generalize some results of complete moment convergence obtained by Chow (Bull. Inst. Math. Acad. Sin. 16:177-201, 1988 and Li and Spătaru (J. Theor. Probab. 18:933-947, 2005 from the i.i.d. case to extended negatively dependent sequences.
Shriram, Duraisamy; Parween, Rizuwana; Lee, Yee Han Dave; Subburaj, Karupppasamy
2017-07-01
Knee osteoarthritis that prevalently occurs at the medial compartment is a progressive chronic disorder affecting the articular cartilage of the knee joint, and lead to loss of joint functionality. Valgus braces have been used as a treatment procedure to unload the medial compartment for patients with medial osteoarthritis. Valgus braces through the application of counteracting external valgus moment shift the load from medial compartment towards the lateral compartment. Previous biomechanical studies focused only on the changes in varus moments before and after wearing the brace. The objective of this study was to investigate the influence of opposing external valgus moment applied by knee braces on the lateral tibial cartilage contact conditions using a 3D finite element model of the knee joint. Finite element simulations were performed on the knee joint model without and with the application of opposing valgus moment to mimic the unbraced and braced conditions. Lateral tibial cartilage contact pressures and contact area, and tibial rotation (varus-valgus and internal-external) were estimated for the complete walking gait cycle. The opposing valgus moment increased the maximum contact pressure and contact area on the lateral tibial cartilage compared to the normal gait moment. A peak contact pressure of 8.2 MPa and maximum cartilage loaded area of 28% (loaded cartilage nodes) on the lateral cartilage with the application of external valgus moment were induced at 50% of the gait cycle. The results show that the use of opposing valgus moment may significantly increase the maximum contact pressures and contact area on the lateral tibial cartilage and increases the risk of articular cartilage damage on the lateral compartment.
Topology of plasma equilibria and the current closure condition
International Nuclear Information System (INIS)
Kocic, S.; Mahajan, S.M.; Hazeltine, R.D.
2005-01-01
A virtually complete description of the topology of stationary incompressible Euler flows and the magnetic field satisfying the magnetostatic equation is given by a theorem due to Arnol'd. We apply this theorem to describe the topology of stationary states of plasmas with significant fluid flow, obeying the Hall magnetohydrodynamics model equations. In the context of the integrability (nonchaotic topology) of the magnetic and velocity fields, we discuss the validity of conditions analogous to that of Greene and Johnson, which, in the case of magnetostatic equations, states that the line integral ∫dl/B is the same for each closed magnetic field line on a given magnetic surface. We also show how this property follows from the existence of a continuous volume-preserving symmetry of the magnetic field
Moment-based boundary conditions for lattice Boltzmann simulations of natural convection in cavities
Allen, Rebecca
2016-06-29
We study a multiple relaxation time lattice Boltzmann model for natural convection with moment-based boundary conditions. The unknown primary variables of the algorithm at a boundary are found by imposing conditions directly upon hydrodynamic moments, which are then translated into conditions for the discrete velocity distribution functions. The method is formulated so that it is consistent with the second order implementation of the discrete velocity Boltzmann equations for fluid flow and temperature. Natural convection in square cavities is studied for Rayleigh numbers ranging from 103 to 108. An excellent agreement with benchmark data is observed and the flow fields are shown to converge with second order accuracy. Copyright © 2016 Inderscience Enterprises Ltd.
Nuclear moments and charge radii of argon isotopes between the neutron-shell closures N=20 and N=28
Blaum, K; Lassen, J; Lievens, P; Marinova, K; Neugart, R
2008-01-01
We report the measurement of optical isotope shifts for $^{40-44}\\!$Ar relative to $^{38}$Ar from which changes in the mean square nuclear charge radii across the 1$\\scriptstyle{f}_{7/2}$ neutron shell are deduced. In addition, the hyperfine structure of $^{41\\!}$Ar and $^{43}$Ar yields the spins, magnetic dipole and electric quadrupole moments, in particular the spin $\\,\\scriptstyle\\textrm{I}$ = 5/2 for $\\,^{43}\\!$Ar. The investigations were carried out by fast-beam collinear laser spectroscopy using highly sensitive detection based on optical pumping and state-selective collisional ionization. Mean square charge radii are now known from $^{32}$Ar to $^{46}$Ar, covering sd-shell as well as $\\scriptstyle{f}_{7/2}$-shell nuclei. They are discussed in the framework of spherical SGII Skyrme-type Hartree-Fock calculations, semi-empirically corrected for quadrupole core polarization. The Zamick-Talmi formula excellently describes the charge radii across the $\\scriptstyle{f}_{7/2}$ neutron shell, as it does for the...
Moment inertia pump analysis used in the Rsg-Gas primary coolant loop under lofa condition
International Nuclear Information System (INIS)
Sudarmono; Setiyanto; Dhandhang, P.; Dibyo, S.; Royadi
1998-01-01
The moment inertia of primary cooling system analysis under LOFA condition has been done. It is potentially one of limiting design constraints of the RSG-GAS safety because the coolant flow rate reduces very rapidly under LOFA condition due to the low inertia circulation pumps. If a loss of flow accident occurs, the mass flow will decrease rapidly and the heat transfer coefficient between cladding and coolant will also decreases. As a consequence the fuel and cladding temperature will increase. The whole core was represented by the 1/4 sector and divided into 19 subchannels and 40 axial nodes. In the present study, moment inertia of pump analysis for RSG-GAS reactor was performed with COBRA-IV-I subchannel code. As the DNB correlation, W-3 Correlation was selected for base case. The flow and power transients under pump trip accident were determined from experiments. The result above compared with the design data are 75 kg m 2 and 81 Kg m 2 respectively. The result shows that the RSG-GAS requires the inertia more than 75 kg m 2
Containment closure time following loss of cooling under shutdown conditions of YGN units 3 and 4
Energy Technology Data Exchange (ETDEWEB)
Seul, Kwang Won; Bang, Young Seok; Kim, Se Won; Kim, Hho Jung [Korea Institute of Nuclear Safety, Taejon (Korea, Republic of)
1998-12-31
The YGN Units 3 and 4 plant conditions during shutdown operation were reviewed to identify the possible event scenarios following the loss of shutdown cooling. The thermal hydraulic analyses were performed for the five cases of RCS configurations under the worst event scenario, unavailable secondary cooling and no RCS inventory makeup, using the RELAP5/MOD3.2 code to investigate the plant behavior. From the analyses results, times to boil, times to core uncovery and times to core heat up were estimated to determine the containment closure time to prevent the uncontrolled release of fission products to atmosphere. These data provide useful information to the abnormal procedure to cope with the event. 6 refs., 7 figs., 2 tabs. (Author)
Containment closure time following loss of cooling under shutdown conditions of YGN units 3 and 4
International Nuclear Information System (INIS)
Seul, Kwang Won; Bang, Young Seok; Kim, Se Won; Kim, Hho Jung
1998-01-01
The YGN Units 3 and 4 plant conditions during shutdown operation were reviewed to identify the possible event scenarios following the loss of shutdown cooling. The thermal hydraulic analyses were performed for the five cases of RCS configurations under the worst event scenario, unavailable secondary cooling and no RCS inventory makeup, using the RELAP5/MOD3.2 code to investigate the plant behavior. From the analyses results, times to boil, times to core uncovery and times to core heat up were estimated to determine the containment closure time to prevent the uncontrolled release of fission products to atmosphere. These data provide useful information to the abnormal procedure to cope with the event
Improvement of storage conditions and closure of the radioactive waste repository - Rozan
International Nuclear Information System (INIS)
Dutton, L.M.C.; Pacey, N.R.; Buckley, M.J.; Thomson, J.G.; Miller, W.; Barraclough, I.; Tomczak, W.; Mitrega, J.; Smietanski, L.
2005-01-01
The Rozan repository is a near-surface repository on the site of an ex-military fort, operated by Radioactive Waste Management Plant (RWMP). Solid or encapsulated waste is consigned to the repository. Low- and medium-activity waste produced in Poland is collected, processed, solidified and prepared for disposal at the Swierk facility. The waste is currently stored or disposed of within the fort structures, these have robust concrete walls, that provide both shielding and containment. The project, funded by the European Commission through the Phare Programme, aimed to improve the storage conditions and determine a strategy for closure achieving two key results; Stakeholder agreement to a strategy for the management and closure of the repository, and; Approval by the National Atomic Energy Agency of the safety case for the selected strategy. The strategy was selected using a multi-criteria analysis methodology at workshops that involved experts, regulators and other stakeholders. The selected strategy proposed that the waste in Facilities 3A and 8 should be left in situ and these facilities should continue to operate until the repository is closed. The waste in Rooms K7 to K9 of Facility 1 and in Facilities 2 and 3 should be retrieved, assayed, treated and packaged prior to redisposal. The short-lived waste that is retrieved from Rooms K7 to K9 of Facility 1 and Facilities 2 and 3 should be emplaced in Facility 8 subject to acceptance by the NAEA of the dose of 0.3mSv/y that might occur at long times in the future from a very unlikely scenario. When operations at the repository end, Facilities 3A and 8 should be covered with a multi-layer cap. Following selection of the strategy, assessment work was undertaken to support the production of the suite of safety cases. (author)
International Nuclear Information System (INIS)
2008-01-01
Corrective Action Unit (CAU) 481 is identified in the Federal Facility Agreement and Consent Order (FFACO) as Area 12 T-Tunnel Conditional Release Storage Yard. CAU 481 is located in Area 12 of the Nevada Test Site, which is approximately 65 miles northwest of Las Vegas, Nevada. This CAU consists of one Corrective Action Site (CAS), CAS 12-42-05, Housekeeping Waste. CAU 481 closure activities were conducted by the Defense Threat Reduction Agency from August 2007 through July 2008 according to the FFACO and Revision 3 of the Sectored Clean-up Work Plan for Housekeeping Category Waste Sites. Closure activities included removal and disposal of construction debris and low-level waste. Drained fluids, steel, and lead was recycled as appropriate. Waste generated during closure activities was appropriately managed and disposed.
Analysis of RLC Elements under Stochastic Conditions Using the First and the Second Moments
Directory of Open Access Journals (Sweden)
WALCZAK, J.
2015-11-01
Full Text Available This paper describes a method of determining the first two moments of the response for basic components of electrical circuits, i.e. resistors, inductors and capacitors. The paper goal was to obtain closed form formulae for the moments describing voltage or current stochastic processes. It has been assumed that the element parameters R (resistance, L (inductance and C (capacitance could be random variables, deterministic functions or stochastic processes and excitations are second order stochastic processes. Moreover, two cases of dependence between the random parameters and the excitation stochastic processes have been considered. The obtained results enable determination of exact solutions for the first two moments without application of numerical algorithms.
Emergency transfer tube closure and process for sealing transfer tube under emergency conditions
International Nuclear Information System (INIS)
Hardin, R.T. Jr.; Marshall, J.R.
1987-01-01
In a nuclear fuel reactor well that includes a transfer tube projecting outwardly from wall thereof, the transfer tube is described having a first closure assembly. The transfer tube has a circumferential flange extending outwardly laterally therefrom, an emergency transfer tube closure therefor comprising; a pair of elongated, vertically-extending U-shaped guides, one U-shaped guide disposed laterally on each side of the transfer tube, each of the U-shaped guides comprising a base and laterally extending flanges thereon, the U-shaped guides having their open ends facing each other, a closure plate, having a surface facing the circumferential flange greater in area than the area circumscribed by the outer circumference of the circumferential flange, vertically disposed the U-shaped guides, the closure plate normally being disposed in a vertical plane just slightly in front of the vertical plane of the circumferential flange, two pairs of rollers, one pair of which is rotatably mounted on each side of the closure plate adjacent the U-shaped guides, riding on the inner portion of each of the flanges of each of the U-shaped guides. Each of the U-shaped guides is provided with a pair of spatially disposed openings on a flange thereof adjacent the wall of the nuclear fuel reactor well, each of the pairs of openings being disposed on each of the U-shaped guides a distance equal to the distance between the center lines of the corresponding pair of rollers riding within the U-shaped guides, each of the openings being sufficiently large to receive a corresponding roller of the pairs of rollers in the U-shaped guides. The openings is shaped on the flanges of the U-shaped guides so that when the pairs of rollers are disposed therein, the face of the closure plate will be in sealing engagement with the circumferential flange of the transfer tube
Directory of Open Access Journals (Sweden)
Amjad Asad
2017-01-01
Full Text Available In this paper, the hydrodynamics of a bubble column is investigated numerically using the discrete bubble model, which tracks the dispersed bubbles individually in a liquid column. The discrete bubble model is combined with the volume of fluid approach to account for a proper free surface boundary condition at the liquid–gas interface. This improves describing the backflow region, which takes place close to the wall region. The numerical simulation is conducted by means of the open source computational fluid dynamics library OpenFOAM®. In order to validate the numerical model, experimental results of a bubble column are used. The numerical prediction shows an overall good agreement compared to the experimental data. The effect of injection conditions and the influence of the drag closures on bubble dynamics are investigated in the current paper. Here, the significant effect of injection boundary conditions on bubble dynamics and flow velocity in the studied cavity is revealed. Moreover, the impact of the choice of the drag closure on the liquid velocity field and on bubble behavior is indicated by comparing three drag closures derived from former studies.
Lindroth, A.; Mölder, M.; Lagergren, F.
2009-08-01
Temperature measurements in trunks and branches in a mature ca. 100 years-old mixed pine and spruce forest in central Sweden were used to estimate the heat storage in the tree biomass. The estimated heat flux in the sample trees and data on biomass distributions were used to scale up to stand level biomass heat fluxes. The rate of change of sensible and latent heat storage in the air layer below the level of the flux measurements was estimated from air temperature and humidity profile measurements and soil heat flux was estimated from heat flux plates and soil temperature measurements. The fluxes of sensible and latent heat from the forest were measured with an eddy covariance system in a tower. The analysis was made for a two-month period in summer of 1995. The tree biomass heat flux was the largest of the estimated storage components and varied between 40 and -35 W m-2 on summer days with nice weather. Averaged over two months the diurnal maximum of total heat storage was 45 W m-2 and the minimum was -35 W m-2. The soil heat flux and the sensible heat storage in air were out of phase with the biomass flux and they reached maximum values that were about 75% of the maximum of the tree biomass heat storage. The energy balance closure improved significantly when the total heat storage was added to the turbulent fluxes. The slope of a regression line with sum of fluxes and storage as independent and net radiation as dependent variable, increased from 0.86 to 0.95 for half-hourly data and the scatter was also reduced. The most significant finding was, however, that during nights with strongly stable conditions when the sensible heat flux dropped to nearly zero, the total storage matched the net radiation nearly perfectly. Another interesting result was that the mean energy imbalance started to increase when the Richardson number became more negative than ca. -0.1. In fact, the largest energy deficit occurred at maximum instability. Our conclusion is that eddy
Directory of Open Access Journals (Sweden)
A. Sakabekov
2016-01-01
Full Text Available We prove existence and uniqueness of the solution of the problem with initial and Maxwell-Auzhan boundary conditions for nonstationary nonlinear one-dimensional Boltzmann’s six-moment system equations in space of functions continuous in time and summable in square by a spatial variable. In order to obtain a priori estimation of the initial and boundary value problem for nonstationary nonlinear one-dimensional Boltzmann’s six-moment system equations we get the integral equality and then use the spherical representation of vector. Then we obtain the initial value problem for Riccati equation. We have managed to obtain a particular solution of this equation in an explicit form.
Masoodi, Habibeh; Jafarzadehpur, Ebrahim; Esmaeili, Alireza; Abolbashari, Fereshteh; Ahmadi Hosseini, Seyed Mahdi
2014-08-01
To evaluate changes of nasal and temporal anterior chamber angle (ACA) in subjects with angle closure glaucoma using Spectralis AS-OCT (SAS-OCT) under dark and light conditions. Based on dark-room gonioscopy, 24 subjects with open angles and 86 with narrow angles participated in this study. The nasal and temporal angle opening distance at 500 μm anterior to the scleral spur (AOD500), nasal and temporal ACA were measured using SAS-OCT in light and dark conditions. In 2 groups, ACA and AOD500 in nasal and temporal quadrants were significantly greater in light compared to dark (all with p=0.000). The AOD500 and ACA were significantly higher in nasal than temporal in measured conditions for 2 groups except the ACA and AOD500 of normal group measured in light. The difference between nasal and temporal in dark (29.07 ± 65.71 μm for AOD500 and 5.7 ± 4.07° for ACA) was greater than light (24.86 ± 79.85 μm for AOD500 and 2.09 ± 7.21° for ACA) condition. But the difference was only significant for ACA (p=0.000). The correlation analysis showed a negative correlation between AOD500 and pupil diameter in temporal and nasal quadrants (both with p=0.000). While temporal AOD500 difference correlated with spherical equivalent, temporal and asal gonioscopy, nasal AOD correlated with IOP, temporal and nasal gonioscopy. Clinically important changes in ACA structure could be detected with SAS-OCT in nasal and temporal quadrants under different illumination intensity. The results could help in improvement of examination condition for better and more accurate assessment of individuals with angle closure glaucoma. Copyright © 2014 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
Matthew Crosston
2015-09-01
Full Text Available This paper is about how the conceptualization of ‘culture’ in intelligence studies has taken on too powerful a role, one that has become too restrictive in its impact on thinking about other intelligence communities, especially non-Western ones. This restriction brings about unintentional cognitive closure that damages intelligence analysis. The argument leans heavily in many ways on the fine work of Desch and Johnston in the discipline of Security Studies, who cogently brought to light over fifteen years ago how ultra-popular cultural theories were best utilized as supplements to traditional realist approaches, but were not in fact capable of supplanting or replacing realist explanations entirely. The discipline of Intelligence Studies today needs a similar ‘intellectual intervention’ as it has almost unknowingly advanced in the post-Cold War era on the coattails of Security Studies but has largely failed to apply the same corrective measures. This effort may be best accomplished by going back to Snyder in the 1970s who warned that culture should be used as the explanation of last resort for Security Studies.
International Nuclear Information System (INIS)
Vaidya, W.V.
1991-01-01
Compliance variations in the threshold regime of a high strength ferritic steel tested under closure-free conditions at room temperature and in air are reported. In contrast to the Paris regime, and irrespective of whether the data during load shedding, at threshold or after postthreshold load increase are considered, it is found that comparatively compliance varies inconsistently in the threshold regime. Therefore, a 1:1 correlation between the averaged optical crack length and that inferred from compliance was not observed. This discrepancy is analyzed. The variations in compliance are utilized to infer the crack front behavior, and the results are discussed in terms of the microstructural impedance. (orig.) With 22 figs., 2 appendices [de
Nieto, Alejandra; Roehl, Holger
2018-03-15
There has been a growing interest in recent years in the assessment of suitable vial/stopper combinations for storage and shipment of frozen drug products. Considering that the glass transition temperature (Tg) of butyl rubber stoppers used in Container Closure Systems (CCS) is between -55°C to -65°C, a storage or shipment temperature of a frozen product below the Tg of the rubber stopper, may require special attention, since below the Tg the rubber becomes more plastic-like and loses its elastic (sealing) characteristics. Thus they risk maintaining Container Closure Integrity (CCI). Given that the rubber regains its elastic properties and reseals after rewarming to ambient temperature, leaks during frozen temperature storage and transportation are transient and the CCI methods used at room temperature conditions are unable to confirm CCI in the frozen state. Hence, several experimental methods have been developed in recent years in order to evaluate CCI at low temperatures. Finite Element (FE) simulations were applied in order to investigate the sealing behaviour of rubber stoppers for the drug product CCS under frozen storage conditions. FE analysis can help reducing the experimental design space and thus number of measurements needed, as they can be used as an ad-on to experimental testing. Several scenarios have been simulated including the effect of thermal history, rubber type, storage time, worst case CCS geometric tolerances and capping pressure. The results of these calculations have been validated with experimental data derived from laboratory experiments (CCI at low temperatures), and a concept for tightness has been developed. It has been concluded that FE simulations have the potential to become a powerful predictive tool towards a better understanding of the influence of cold storage on the rubber sealing properties (and hence on CCI) when dealing with frozen drug products. Copyright © 2018, Parenteral Drug Association.
Structural analysis of closure bolts for shipping casks
International Nuclear Information System (INIS)
Mok, G.C.; Fischer, L.E.
1993-04-01
This paper identifies the active forces and moments in a closure bolt of a shipping cask. It examines the interactions of these forces/moments and suggest simplified methods for their analysis. The paper also evaluates the role that the forces and moments play in the structure integrity of the closure bolt and recommends stress limits and desirable practices to ensure its integrity
Kopferman, H; Massey, H S W
1958-01-01
Nuclear Moments focuses on the processes, methodologies, reactions, and transformations of molecules and atoms, including magnetic resonance and nuclear moments. The book first offers information on nuclear moments in free atoms and molecules, including theoretical foundations of hyperfine structure, isotope shift, spectra of diatomic molecules, and vector model of molecules. The manuscript then takes a look at nuclear moments in liquids and crystals. Discussions focus on nuclear paramagnetic and magnetic resonance and nuclear quadrupole resonance. The text discusses nuclear moments and nucl
Conditional dissipation of scalars in homogeneous turbulence: Closure for MMC modelling
Wandel, Andrew P.
2013-08-01
While the mean and unconditional variance are to be predicted well by any reasonable turbulent combustion model, these are generally not sufficient for the accurate modelling of complex phenomena such as extinction/reignition. An additional criterion has been recently introduced: accurate modelling of the dissipation timescales associated with fluctuations of scalars about their conditional mean (conditional dissipation timescales). Analysis of Direct Numerical Simulation (DNS) results for a passive scalar shows that the conditional dissipation timescale is of the order of the integral timescale and smaller than the unconditional dissipation timescale. A model is proposed: the conditional dissipation timescale is proportional to the integral timescale. This model is used in Multiple Mapping Conditioning (MMC) modelling for a passive scalar case and a reactive scalar case, comparing to DNS results for both. The results show that this model improves the accuracy of MMC predictions so as to match the DNS results more closely using a relatively-coarse spatial resolution compared to other turbulent combustion models.
Directory of Open Access Journals (Sweden)
Mahmood Yahyai
2015-12-01
Full Text Available Column-tree moment resisting frames, as the efficient shop-welded and field-bolted structural systems, are used in many countries. Very limited research has been carried out on such systems under fire conditions. This paper presents experimental investigations of the behavior of beam and bolted splice connections in steel column-tree moment resisting frames exposed to fire. Two full-scale steel sub-frames with different splice connections were tested under ISO 834 standard fire. The flange splice plates were configured as a single plate with single shear bolts in first specimen, and as double plates with double shear bolts in second specimen. The observation of thermal and structural fire behaviors including temperature histories, temperature-deflection of the beam, temperature-rotation of splice connections and failure modes were investigated. The temperature-deflection and temperature-rotation curves remained in the elastic range until about 600°C. Beyond 600°C, the behavior would be highly nonlinear plastic. The beam splice connection failed due to shear fracture of top bolts at temperatures beyond 750°C. Consequently, stub beam web failed at those temperatures because of block-shear. Using double plates with double shear bolts for flange splices would enhance the temperature resistance and rotational capacity of the beam splice connections. Both tests results confirmed that specimens retain the capacity to support the design load when the average beam temperature does not exceed 600°C. This temperature limit confirms the temperature criteria provided by ASTM E119 and ANSI/UL 263 for a restrained beam, and can be used to specify the minimum fire resistance criteria for beams in column-tree MRFs. The measured time-deflection curves showed that the restrained fire resistance rating for both unprotected specimens obtained about 15 minutes in both tests.
Montgomery County of Maryland — This is an up to date map of current road closures in Montgomery County.This dataset is updated every few minutes from the Department of Transportation road closure...
Caille, Soline; Samson, Alain; Salmon, Jean-Michel
2017-01-01
Aims: The management of O2, CO2 and SO2 at bottling and the choice of closure are two key factors of the shelf life of bottled wines before bringing them to market. The impact of eight closures (four screw caps, two synthetic stoppers and two technical stoppers) was evaluated on a red Merlot/Tannat wine. The results of a rosé wine are also discussed. Methods and results: Analytical monitoring (O2, CO2, SO2, aphrometric pressure, L*, a*, b*) was carried out over 538 days of storage at 20°C,...
Wallhead, Ian R.; Edwards, Lyndon; Poole, Peter
1994-01-01
The optical method of caustics has been successfully extended to enable stress intensity factors as low as 1MPa square root of m to be determined accurately for central fatigue cracks in 2024-T3 aluminium alloy test panels. The feasibility of using this technique to study crack closure, and to determine the effective stress intensity factor range, Delta K(sub eff), has been investigated. Comparisons have been made between the measured values of stress intensity factor, K(sub caus), and corresponding theoretical values, K(sub theo), for a range of fatigue cracks grown under different loading conditions. The values of K(sub caus) and K(sub theo) were in good agreement at maximum stress, where the cracks are fully open, while K(sub caus) exceeded K(sub theo) at minimum stress, due to crack closure. However, the levels of crack closure and values of Delta K(sub eff) obtained could not account for the variations of crack growth rate with loading conditions. It is concluded that the values of Delta K(sub eff), based on caustic measurements in a 1/square root of r stress field well outside the plastic zone, do not fully reflect local conditions which control crack tip behavior.
2002-01-01
Experiment IS358 uses the intense and pure beams of copper isotopes provided by the ISOLDE RILIS (resonance ionization laser ion source). The isotopes are implanted and oriented in the low temperature nuclear orientation set-up NICOLE. Magnetic moments are measured by $\\beta$-NMR. Copper (Z=29), with a single proton above the proton-magic nickel isotopes provides an ideal testground for precise shell model calculations of magnetic moments and their experimental verification. In the course of our experiments we already determined the magnetic moments of $^{67}$Ni, $^{67}$Cu, $^{68g}$Cu, $^{69}$Cu and $^{71}$Cu which provide important information on the magicity of the N=40 subshell closure. In 2001 we plan to conclude our systematic investigations by measuring the magnetic moment of the neutron-deficient isotope $^{59}$Cu. This will pave the way for a subsequent study of the magnetic moment of $^{57}$Cu with a complementary method.
International Nuclear Information System (INIS)
Hutchinson, I.P.G.; Ellison, R.D.
1992-01-01
Closure of a waste management unit can be either permanent or temporary. Permanent closure may be due to: economic factors which make it uneconomical to mine the remaining minerals; depletion of mineral resources; physical site constraints that preclude further mining and beneficiation; environmental, regulatory or other requirements that make it uneconomical to continue to develop the resources. Temporary closure can occur for a period of several months to several years, and may be caused by factors such as: periods of high rainfall or snowfall which prevent mining and waste disposal; economic circumstances which temporarily make it uneconomical to mine the target mineral; labor problems requiring a cessation of operations for a period of time; construction activities that are required to upgrade project components such as the process facilities and waste management units; and mine or process plant failures that require extensive repairs. Permanent closure of a mine waste management unit involves the provision of durable surface containment features to protect the waters of the State in the long-term. Temporary closure may involve activities that range from ongoing maintenance of the existing facilities to the installation of several permanent closure features in order to reduce ongoing maintenance. This paper deals with the permanent closure features
Directory of Open Access Journals (Sweden)
Vidal Jean-Claude
2017-01-01
Full Text Available Aims: The management of O2, CO2 and SO2 at bottling and the choice of the closure are two key factors of the shelf life of wine in bottles before bringing them to market. The impact of four screw caps, two synthetic and two technical corks was evaluated on a red wine of Merlot/Tannat. Methods and results: Analytical monitoring (O2, CO2, SO2, aphrometric pressure, L*, a*, b* was carried out during 538 days of storage at 20 °C. Two sensory analyses at 10 and 17 months completed the study. The wine was bottled with an average total oxygen content of 2 mg/L. The heterogeneity intra and inter procedure was controlled, including for the dissolved carbon dioxide content. Conclusion: Unlike closures with highest OTR, the two technical corks and the two screw caps with Saranex seal, harboring the lowest OTR, matched with the wines exhibiting a low total O2 content at equilibrium (from 4th to 18th month, with more free SO2 and less changed colour. However this OTR gradient (5 to 67 μg/d observed through the physicochemical analyses was not necessarily confirmed by both sensory analyses performed. Significance and impact of study: This study puts into perspective the impact of OTR closure on sensory characteristics evolution of wine consumed during the first two years, especially when the total oxygen at bottling exceeds 1.5 mg/L.
Vidal, Jean-Claude; Caille, Soline; Samson, Alain; Salmon, Jean-Michel
2017-01-01
Aims: The management of O2, CO2 and SO2 at bottling and the choice of the closure are two key factors of the shelf life of wine in bottles before bringing them to market. The impact of four screw caps, two synthetic and two technical corks was evaluated on a red wine of Merlot/Tannat. Methods and results: Analytical monitoring (O2, CO2, SO2, aphrometric pressure, L*, a*, b*) was carried out during 538 days of storage at 20 °C. Two sensory analyses at 10 and 17 months completed the stu...
Novae Restauration
2012-01-01
Christmas Restaurant closures Please note that the Restaurant 1 and Restaurant 3 will be closed from Friday, 21 December at 5 p.m. to Sunday, 6 January, inclusive. They will reopen on Monday, 7 January 2013. Restaurant 2 closure for renovation To meet greater demand and to modernize its infrastructure, Restaurant 2 will be closed from Monday, 17 December. On Monday, 14 January 2013, Sophie Vuetaz’s team will welcome you to a renovated self-service area on the 1st floor. The selections on the ground floor will also be expanded to include pasta and pizza, as well as snacks to eat in or take away. To ensure a continuity of service, we suggest you take your break at Restaurant 1 or Restaurant 3 (Prévessin).
International Nuclear Information System (INIS)
Vaidya, W.V.
1991-01-01
Near-threshold fatigue crack propagation behavior of a high strength steel was investigated in laboratory air under closure-free testing conditions at R = 0.7 (= R eff ), and at two different K-gradients. Depending on the criterion assumed, the threshold value differed; the criterion of non-propagation gave a lower threshold value than that assumed by the propagation criterion. Nevertheless, the subsequent propagation following a load increase was discontinuous in both the cases, and da/dN vs ΔK curves obtained on the same specimen during the K-decreasing and the K-increasing test were not necessarily identical in the threshold regime. This behavior, hysteresis, is analyzed mainly from the experimental viewpoint, and it is shown that hysteresis is not an artifact. (orig.) With 13 figs., 3 appendices [de
Directory of Open Access Journals (Sweden)
Kupavtsev Vladimir Vladimirovich
2014-02-01
Full Text Available The method of two-sided evaluations is extended to the problems of stability of an elastic non-uniformly compressed rod, the variation formulations of which may be presented in terms of internal bending moments with uniform integral conditions. The problems are considered, in which one rod end is fixed and the other rod end is either restraint or pivoted, or embedded into a support which may be shifted in a transversal direction.For the substantiation of the lower evaluations determination, a sequence of functionals is constructed, the minimum values of which are the lower evaluations for the minimum critical value of the loading parameter of the rod, and the calculation process is reduced to the determination of the maximum eigenvalues of modular matrices. The matrix elements are expressed in terms of integrals of basic functions depending on the type of fixation of the rod ends. The basic functions, with the accuracy up to a linear polynomial, are the same as the bending moments arising with the bifurcation of the equilibrium of a rod with a constant cross-section compressed by longitudinal forces at the rod ends. The calculation of the upper evaluation is reduced to the determination of the maximum eigenvalue of the matrix, which almost coincides with one of the elements of the modular matrices. It is noted that the obtained upper bound evaluation is not worse thanthe evaluation obtained by the Ritz method with the use of the same basic functions.
Directory of Open Access Journals (Sweden)
A. Sarayev
2014-02-01
Full Text Available This study is aimed at investigation of a car collision with a pedestrian under limited visibility condi-tions. For this purpose an expert has to analyze the accident details and determine the critical time at which the car driver must take an action to avoid the collision. The analysis is complicated due to the fact that the vehicle is equipped with an anti-blocking braking system and does not leave a braking trace on the pavement. In this case, a relevant expert analysis technique does not exist. The development of such techniques as the basis of this scientific work is given.
Avar, Z; Tóth, B; Zacher, P
1979-01-01
Authors have performed the McDonald cerclage operation on 172 gravidae because of cervical incompetence. From these pregnancies 80.2 per cent of the infants have survived over the sixth day. While with operations performed on the basis of extended indications for surgery an effect of 56.5 per cent was achieved, it was in cases of classical ones 92.8 per cent. Two complicated cases are reported caused by blastospores or bacteria respectively, isolated also in the vaginal secretion which have ascended into the uterine cavity. Both cases resulted in fetal death and in a septic condition of the mother. It is emphasized that the normal vaginal bioflora is essential condition for the cervical suture.
Energy Technology Data Exchange (ETDEWEB)
Denham, M. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Millings, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2012-08-28
This document provides information specific to H-Area waste tanks that enables a flow and transport model with limited chemical capabilities to account for varying waste release from the tanks through time. The basis for varying waste release is solubilities of radionuclides that change as pore fluids passing through the waste change in composition. Pore fluid compositions in various stages were generated by simulations of tank grout degradation. The first part of the document describes simulations of the degradation of the reducing grout in post-closure tanks. These simulations assume flow is predominantly through a water saturated porous medium. The infiltrating fluid that reacts with the grout is assumed to be fluid that has passed through the closure cap and into the tank. The results are three stages of degradation referred to as Reduced Region II, Oxidized Region II, and Oxidized Region III. A reaction path model was used so that the transitions between each stage are noted by numbers of pore volumes of infiltrating fluid reacted. The number of pore volumes to each transition can then be converted to time within a flow and transport model. The bottoms of some tanks in H-Area are below the water table requiring a different conceptual model for grout degradation. For these simulations the reacting fluid was assumed to be 10% infiltrate through the closure cap and 90% groundwater. These simulations produce an additional four pore fluid compositions referred to as Conditions A through D and were intended to simulate varying degrees of groundwater influence. The most probable degradation path for the submerged tanks is Condition C to Condition D to Oxidized Region III and eventually to Condition A. Solubilities for Condition A are estimated in the text for use in sensitivity analyses if needed. However, the grout degradation simulations did not include sufficient pore volumes of infiltrating fluid for the grout to evolve to Condition A. Solubility controls for use
Directory of Open Access Journals (Sweden)
U. Dusek
2011-09-01
Full Text Available We investigate the CCN activity of freshly emitted biomass burning particles and their hygroscopic growth at a relative humidity (RH of 85%. The particles were produced in the Mainz combustion laboratory by controlled burning of various wood types. The water uptake at sub- and supersaturations is parameterized by the hygroscopicity parameter, κ (c.f. Petters and Kreidenweis, 2007. For the wood burns, κ is low, generally around 0.06. The main emphasis of this study is a comparison of κ derived from measurements at sub- and supersaturated conditions (κ_{G} and κ_{CCN}, in order to see whether the water uptake at 85% RH can predict the CCN properties of the biomass burning particles. Differences in κ_{G}and κ_{CCN} can arise through solution non-idealities, the presence of slightly soluble or surface active compounds, or non-spherical particle shape. We find that κ_{G} and κ_{CCN} agree within experimental uncertainties (of around 30% for particle sizes of 100 and 150 nm; only for 50 nm particles is κ_{CCN} larger than κ_{G} by a factor of 2. The magnitude of this difference and its dependence on particle size is consistent with the presence of surface active organic compounds. These compounds mainly facilitate the CCN activation of small particles, which form the most concentrated solution droplets at the point of activation. The 50 nm particles, however, are only activated at supersaturations higher than 1% and are therefore of minor importance as CCN in ambient clouds. By comparison with the actual chemical composition of the biomass burning particles, we estimate that the hygroscopicity of the water-soluble organic carbon (WSOC fraction can be represented by a κ_{WSOC} value of approximately 0.2. The effective hygroscopicity of a typical wood burning particle can therefore be represented by a linear mixture of an inorganic component with κ ≅ 0.6, a WSOC
Revisiting the Landau fluid closure.
Hunana, P.; Zank, G. P.; Webb, G. M.; Adhikari, L.
2017-12-01
Advanced fluid models that are much closer to the full kinetic description than the usual magnetohydrodynamic description are a very useful tool for studying astrophysical plasmas and for interpreting solar wind observational data. The development of advanced fluid models that contain certain kinetic effects is complicated and has attracted much attention over the past years. Here we focus on fluid models that incorporate the simplest possible forms of Landau damping, derived from linear kinetic theory expanded about a leading-order (gyrotropic) bi-Maxwellian distribution function f_0, under the approximation that the perturbed distribution function f_1 is gyrotropic as well. Specifically, we focus on various Pade approximants to the usual plasma response function (and to the plasma dispersion function) and examine possibilities that lead to a closure of the linear kinetic hierarchy of fluid moments. We present re-examination of the simplest Landau fluid closures.
International Nuclear Information System (INIS)
Kobayashi, Toshio; Adachi, Naohito; Masuda, Kiyoshi
1998-01-01
In a design of a thick RC slab such as a basemat of a nuclear reactor building, the design method as same as for RC column is usually used. In this method, bending moment and axial force which are obtained by linear Finite Element Method (FEM) for external force are considered. But the assumption for linear FEM in which concrete participates for tensile stress is different from that for reinforcement design in which concrete does not participate for tensile stress. This difference of the assumption results that in-plane tensile strain at the center of the slab depth in the reinforcement design is larger than that in linear FEM. Some effects will appear in stress distribution if this tensile strain is constrained by boundary condition. In this paper, a practical method to evaluate the boundary constrain effects for this in-plane tensile strain is proposed and a simulation analysis of a thick reinforced concrete slab with a large opening for out-of-plane force is also reported. (author)
Assembling Transgender Moments
Greteman, Adam J.
2017-01-01
In this article, the author seeks to assemble moments--scholarly, popular, and aesthetic--in order to explore the possibilities that emerge as moments collect in education's encounters with the needs, struggles, and possibilities of transgender lives and practices. Assembling moments, the author argues, illustrates the value of "moments"…
Full closure strategic analysis.
2014-07-01
The full closure strategic analysis was conducted to create a decision process whereby full roadway : closures for construction and maintenance activities can be evaluated and approved or denied by CDOT : Traffic personnel. The study reviewed current...
Sternal exploration or closure
VAC - vacuum-assisted closure - sternal wound; Sternal dehiscence; Sternal infection ... in the wound to look for signs of infection Remove dead or infected ... use a VAC (vacuum-assisted closure) dressing. It is a negative ...
Reconstruction of convex bodies from moments
DEFF Research Database (Denmark)
Hörrmann, Julia; Kousholt, Astrid
We investigate how much information about a convex body can be retrieved from a finite number of its geometric moments. We give a sufficient condition for a convex body to be uniquely determined by a finite number of its geometric moments, and we show that among all convex bodies, those which......- rithm that approximates a convex body using a finite number of its Legendre moments. The consistency of the algorithm is established using the stabil- ity result for Legendre moments. When only noisy measurements of Legendre moments are available, the consistency of the algorithm is established under...
Stochastic Generalized Method of Moments
Yin, Guosheng; Ma, Yanyuan; Liang, Faming; Yuan, Ying
2011-01-01
The generalized method of moments (GMM) is a very popular estimation and inference procedure based on moment conditions. When likelihood-based methods are difficult to implement, one can often derive various moment conditions and construct the GMM objective function. However, minimization of the objective function in the GMM may be challenging, especially over a large parameter space. Due to the special structure of the GMM, we propose a new sampling-based algorithm, the stochastic GMM sampler, which replaces the multivariate minimization problem by a series of conditional sampling procedures. We develop the theoretical properties of the proposed iterative Monte Carlo method, and demonstrate its superior performance over other GMM estimation procedures in simulation studies. As an illustration, we apply the stochastic GMM sampler to a Medfly life longevity study. Supplemental materials for the article are available online. © 2011 American Statistical Association.
Stochastic Generalized Method of Moments
Yin, Guosheng
2011-08-16
The generalized method of moments (GMM) is a very popular estimation and inference procedure based on moment conditions. When likelihood-based methods are difficult to implement, one can often derive various moment conditions and construct the GMM objective function. However, minimization of the objective function in the GMM may be challenging, especially over a large parameter space. Due to the special structure of the GMM, we propose a new sampling-based algorithm, the stochastic GMM sampler, which replaces the multivariate minimization problem by a series of conditional sampling procedures. We develop the theoretical properties of the proposed iterative Monte Carlo method, and demonstrate its superior performance over other GMM estimation procedures in simulation studies. As an illustration, we apply the stochastic GMM sampler to a Medfly life longevity study. Supplemental materials for the article are available online. © 2011 American Statistical Association.
Tenhunen, J D; Lange, O L; Braun, M
1981-08-01
Shrubs of the Mediterranean sclerophyllous species Arbutus unedo and Quercus ilex were studied under simulated habitat conditions in an environmental chamber. Temperature, humidity, and light intensity were altered stepwise to simulate diurnal changes in conditions similar to those measured in an evergreen macchia in Sobreda, Portugal. Leaves were enclosed in cuvettes which reproduced the growth chamber climate and which allowed measurement of gas exchange. Increasing atmospheric stress in the form of higher temperature and lower humidity on successive days gradually results in midday depression of transpiration rate and net photosynthesis rate of leaves due to midday stomatal closure.
Bolin, Michael
2010-01-01
If you're ready to use Closure to build rich web applications with JavaScript, this hands-on guide has precisely what you need to learn this suite of tools in depth. Closure makes it easy for experienced JavaScript developers to write and maintain large and complex codebases -- as Google has demonstrated by using Closure with Gmail, Google Docs, and Google Maps. Author and Closure contributor Michael Bolin has included numerous code examples and best practices, as well as valuable information not available publicly until now. You'll learn all about Closure's Library, Compiler, Templates, tes
Liebert, Adam; Wabnitz, Heidrun; Elster, Clemens
2012-05-01
Time-resolved near-infrared spectroscopy allows for depth-selective determination of absorption changes in the adult human head that facilitates separation between cerebral and extra-cerebral responses to brain activation. The aim of the present work is to analyze which combinations of moments of measured distributions of times of flight (DTOF) of photons and source-detector separations are optimal for the reconstruction of absorption changes in a two-layered tissue model corresponding to extra- and intra-cerebral compartments. To this end we calculated the standard deviations of the derived absorption changes in both layers by considering photon noise and a linear relation between the absorption changes and the DTOF moments. The results show that the standard deviation of the absorption change in the deeper (superficial) layer increases (decreases) with the thickness of the superficial layer. It is confirmed that for the deeper layer the use of higher moments, in particular the variance of the DTOF, leads to an improvement. For example, when measurements at four different source-detector separations between 8 and 35 mm are available and a realistic thickness of the upper layer of 12 mm is assumed, the inclusion of the change in mean time of flight, in addition to the change in attenuation, leads to a reduction of the standard deviation of the absorption change in the deeper tissue layer by a factor of 2.5. A reduction by another 4% can be achieved by additionally including the change in variance.
Social and macro economic impact of closure
International Nuclear Information System (INIS)
Medeliene, D.
1999-01-01
The social consequences of closure of Ignalina NPP will largely depend on the actions the Government takes. If it puts in place the conditions which enable the International Financial Institutions to assist Lithuania, both in providing loans and grants for decommissioning and (in the case of the EU) providing Structural Adjustment Funds for the regional economic development of the Visaginas area, then solutions to the problems of closure can be found. But if the Government delays putting into place the necessary conditions, then Lithuania will be left to solve the problems of - inter alia necessary - closure of Ignalina NPP on its own. (author)
International Nuclear Information System (INIS)
Lipkin, H.J.
1983-06-01
The new experimental values of hyperon magnetic moments are compared with sum rules predicted from general quark models. Three difficulties are encountered which are not easily explained by simple models. The isovector contributions of nonstrange quarks to hyperon moments are smaller than the corresponding contribution to nucleon moments, indicating either appreciable configuration mixing present in hyperon wave functions and absent in nucleons or an additional isovector contribution beyond that of valence quarks; e.g. from a pion cloud. The large magnitude of the ω - moment may indicate that the strange quark contribution to the ω moments is considerably larger than the value μ(#betta#) predicted by simple models which have otherwise been very successful. The set of controversial values from different experiments of the μ - moment include a value very close to -(1/2)μ(μ + ) which would indicate that strange quarks do not contribute at all to the μ moments. (author)
Stief, Thomas; Peikenkamp, Klaus
2015-01-01
Stress occurring at the feet while wearing footwear is often determined using pressure measurement systems. However, other forms of stress, such as bending, torsional and shear loadings, cannot be detected in shoes during day-to-day activities. Nevertheless, the detection of these types of stresses would be helpful for understanding the mechanical aspects of various kinds of hard and soft tissue injuries. Therefore, we describe the development of a new measuring device that allows the reliable determination of bending and torsional load at the foot in shoes. The system consists of a measuring insole and an analogue device with Bluetooth interface. The specific shape of the insole base layer, the positions of the strain gauges, and the interconnections between them have all been selected in such a way so as to isolate bending and torsional moment detections in the medial and lateral metatarsal region. The system was calibrated using a classical two-point test procedure. A single case study was executed to evaluate the new device for practical use. This application consisted of one subject wearing neutral shoes walking on a treadmill. The calibration results (coefficients of determination R(2) > 0.999) show that bending and torsional load can be reliably detected using the measurement system presented. In the single case study, alternating bending and torsional load can be detected during walking, and the shape of the detected bending moments can be confirmed by the measurements of Arndt et al. (J Biomech 35:621-8, 2002). Despite some limitations, the presented device allows for the reliable determination of bending and torsional stresses at the foot in shoes.
Marciano, William J
2010-01-01
This book provides a self-contained description of the measurements of the magnetic dipole moments of the electron and muon, along with a discussion of the measurements of the fine structure constant, and the theory associated with magnetic and electric dipole moments. Also included are the searches for a permanent electric dipole moment of the electron, muon, neutron and atomic nuclei. The related topic of the transition moment for lepton flavor violating processes, such as neutrinoless muon or tauon decays, and the search for such processes are included as well. The papers, written by many o
International Nuclear Information System (INIS)
Klahn, F.C.; Nolan, J.H.; Wills, C.
1982-01-01
This invention relates to a closure mechanism for closing openings such as the bore of a conduit and for releasably securing members within the bore. More particularly, this invention relates to a closure mechanism for tubular irradiation surveillance specimen assembly holders used in nuclear reactors
Spins, moments and radii of Cd isotopes
International Nuclear Information System (INIS)
Hammen, Michael
2013-01-01
The complex nature of the nucleon-nucleon interaction and the wide range of systems covered by the roughly 3000 known nuclides leads to a multitude of effects observed in nuclear structure. Among the most prominent ones is the occurence of shell closures at so-called ''magic numbers'', which are explained by the nuclear shell model. Although the shell model already is on duty for several decades, it is still constantly extended and improved. For this process of extension, fine adjustment and verification, it is important to have experimental data of nuclear properties, especially at crucial points like in the vicinity of shell closures. This is the motivation for the work performed in this thesis: the measurement and analysis of nuclear ground state properties of the isotopic chain of 100-130 Cd by collinear laser spectroscopy. The experiment was conducted at ISOLDE/CERN using the collinear laser spectroscopy apparatus COLLAPS. This experiment is the continuation of a run on neutral atomic cadmium from A = 106 to A = 126 and extends the measured isotopes to even more exotic species. The required gain in sensitivity is mainly achieved by using a radiofrequency cooler and buncher for background reduction and by using the strong 5s 2 S 1/2 →5p 2 P 3/2 transition in singly ionized Cd. The latter requires a continuous wave laser system with a wavelength of 214.6 nm, which has been developed during this thesis. Fourth harmonic generation of an infrared titanium sapphire laser is achieved by two subsequent cavity-enhanced second harmonic generations, leading to the production of deep-UV laser light up to about 100 mW. The acquired data of the Z=48 Cd isotopes, having one proton pair less than the Z=50 shell closure at tin, covers the isotopes from N=52 up to N=82 and therefore almost the complete region between the neutron shell closures N=50 and N=82. The isotope shifts and the hyperfine structures of these isotopes have been recorded and the magnetic dipole moments
Spins, moments and radii of Cd isotopes
Energy Technology Data Exchange (ETDEWEB)
Hammen, Michael
2013-10-30
recorded and the magnetic dipole moments, the electric quadrupole moments, spins and changes in mean square charge radii are extracted. The obtained data reveal among other features an extremely linear behaviour of the quadrupole moments of the I=11/2{sup -} isomeric states and a parabolic development in differences in mean square nuclear charge radii between ground and isomeric state. The development of charge radii between the shell closures is smooth, exposes a regular odd-even staggering and can be described and interpreted in the model of Zamick and Thalmi.
Biomechanics Strategies for Space Closure in Deep Overbite
Directory of Open Access Journals (Sweden)
Harryanto Wijaya
2013-07-01
Full Text Available Space closure is an interesting aspect of orthodontic treatment related to principles of biomechanics. It should be tailored individually based on patient’s diagnosis and treatment plan. Understanding the space closure biomechanics basis leads to achieve the desired treatment objective. Overbite deepening and losing posterior anchorage are the two most common unwanted side effects in space closure. Conventionally, correction of overbite must be done before space closure resulted in longer treatment. Application of proper space closure biomechanics strategies is necessary to achieve the desired treatment outcome. This cases report aimed to show the space closure biomechanics strategies that effectively control the overbite as well as posterior anchorage in deep overbite patients without increasing treatment time. Two patients who presented with class II division 1 malocclusion were treated with fixed orthodontic appliance. The primary strategies included extraction space closure on segmented arch that employed two-step space closure, namely single canine retraction simultaneously with incisors intrusion followed by enmasse retraction of four incisors by using differential moment concept. These strategies successfully closed the space, corrected deep overbite and controlled posterior anchorage simultaneously so that the treatment time was shortened. Biomechanics strategies that utilized were effective to achieve the desired treatment outcome.
Moment distributions of phase-type
DEFF Research Database (Denmark)
Bladt, Mogens; Nielsen, Bo Friis
2012-01-01
Both matrix-exponential and phase-type distributions have a number of important closure properties. Among those are the distributions of the age and residual life-time of a stationary renewal process with inter-arrivals of either type. In this talk we show that the spread, which is the sum of the...... with phase-type distributions. For the first order distribution we present an explicit formula for the related Lorenz curve and Gini index. Moment distributions of orders one, two and three have been extensively used in areas such as economy, physics, demography and civil engineering....
Electric dipole moments reconsidered
International Nuclear Information System (INIS)
Rupertsberger, H.
1989-01-01
The electric dipole moments of elementary particles, atoms, molecules and their connection to the electric susceptibility are discussed for stationary states. Assuming rotational invariance it is emphasized that for such states only in the case of a parity and time reversal violating interaction the considered particles can obtain a nonvanishing expectation value for the electric dipole moment. 1 fig., 13 refs. (Author)
DEFF Research Database (Denmark)
Swann, Andrew Francis; Madsen, Thomas Bruun
2012-01-01
We introduce a notion of moment map adapted to actions of Lie groups that preserve a closed three-form. We show existence of our multi-moment maps in many circumstances, including mild topological assumptions on the underlying manifold. Such maps are also shown to exist for all groups whose second...
Energy Technology Data Exchange (ETDEWEB)
Michael Ramsey-Musolf; Wick Haxton; Ching-Pang Liu
2002-03-29
Nuclear anapole moments are parity-odd, time-reversal-even E1 moments of the electromagnetic current operator. Although the existence of this moment was recognized theoretically soon after the discovery of parity nonconservation (PNC), its experimental isolation was achieved only recently, when a new level of precision was reached in a measurement of the hyperfine dependence of atomic PNC in 133Cs. An important anapole moment bound in 205Tl also exists. In this paper, we present the details of the first calculation of these anapole moments in the framework commonly used in other studies of hadronic PNC, a meson exchange potential that includes long-range pion exchange and enough degrees of freedom to describe the five independent S-P amplitudes induced by short-range interactions. The resulting contributions of pi-, rho-, and omega-exchange to the single-nucleon anapole moment, to parity admixtures in the nuclear ground state, and to PNC exchange currents are evaluated, using configuration-mixed shell-model wave functions. The experimental anapole moment constraints on the PNC meson-nucleon coupling constants are derived and compared with those from other tests of the hadronic weak interaction. While the bounds obtained from the anapole moment results are consistent with the broad ''reasonable ranges'' defined by theory, they are not in good agreement with the constraints from the other experiments. We explore possible explanations for the discrepancy and comment on the potential importance of new experiments.
International Nuclear Information System (INIS)
Michael Ramsey-Musolf; Wick Haxton; Ching-Pang Liu
2002-01-01
Nuclear anapole moments are parity-odd, time-reversal-even E1 moments of the electromagnetic current operator. Although the existence of this moment was recognized theoretically soon after the discovery of parity nonconservation (PNC), its experimental isolation was achieved only recently, when a new level of precision was reached in a measurement of the hyperfine dependence of atomic PNC in 133Cs. An important anapole moment bound in 205Tl also exists. In this paper, we present the details of the first calculation of these anapole moments in the framework commonly used in other studies of hadronic PNC, a meson exchange potential that includes long-range pion exchange and enough degrees of freedom to describe the five independent S-P amplitudes induced by short-range interactions. The resulting contributions of pi-, rho-, and omega-exchange to the single-nucleon anapole moment, to parity admixtures in the nuclear ground state, and to PNC exchange currents are evaluated, using configuration-mixed shell-model wave functions. The experimental anapole moment constraints on the PNC meson-nucleon coupling constants are derived and compared with those from other tests of the hadronic weak interaction. While the bounds obtained from the anapole moment results are consistent with the broad ''reasonable ranges'' defined by theory, they are not in good agreement with the constraints from the other experiments. We explore possible explanations for the discrepancy and comment on the potential importance of new experiments
Schmüdgen, Konrad
2017-01-01
This advanced textbook provides a comprehensive and unified account of the moment problem. It covers the classical one-dimensional theory and its multidimensional generalization, including modern methods and recent developments. In both the one-dimensional and multidimensional cases, the full and truncated moment problems are carefully treated separately. Fundamental concepts, results and methods are developed in detail and accompanied by numerous examples and exercises. Particular attention is given to powerful modern techniques such as real algebraic geometry and Hilbert space operators. A wide range of important aspects are covered, including the Nevanlinna parametrization for indeterminate moment problems, canonical and principal measures for truncated moment problems, the interplay between Positivstellensätze and moment problems on semi-algebraic sets, the fibre theorem, multidimensional determinacy theory, operator-theoretic approaches, and the existence theory and important special topics of multidime...
An online visual loop closure detection method for indoor robotic navigation
Erhan, Can; Sariyanidi, Evangelos; Sencan, Onur; Temeltas, Hakan
2015-01-01
In this paper, we present an enhanced loop closure method* based on image-to-image matching relies on quantized local Zernike moments. In contradistinction to the previous methods, our approach uses additional depth information to extract Zernike moments in local manner. These moments are used to represent holistic shape information inside the image. The moments in complex space that are extracted from both grayscale and depth images are coarsely quantized. In order to find out the similarity between two locations, nearest neighbour (NN) classification algorithm is performed. Exemplary results and the practical implementation case of the method are also given with the data gathered on the testbed using a Kinect. The method is evaluated in three different datasets of different lighting conditions. Additional depth information with the actual image increases the detection rate especially in dark environments. The results are referred as a successful, high-fidelity online method for visual place recognition as well as to close navigation loops, which is a crucial information for the well known simultaneously localization and mapping (SLAM) problem. This technique is also practically applicable because of its low computational complexity, and performing capability in real-time with high loop closing accuracy.
Directory of Open Access Journals (Sweden)
A D Macleod
2009-01-01
Full Text Available Aim: To observe the incidence of full or partial eyelid closure at death. Materials and Methods: The presence of ptosis was recorded in 100 consecutive hospice patient deaths. Results: Majority (63% of the patients died with their eyes fully closed, however, 37% had bilateral ptosis at death, with incomplete eye closure. In this study, central nervous system tumor involvement and/or acute hepatic encephalopathy appeared to be pre-mortem risk factors of bilateral ptosis at death. Conclusion: Organicity and not psychogenicity is, therefore, the likely etiology of failure of full eyelid closure at death.
RCRA corrective action and closure
International Nuclear Information System (INIS)
1995-02-01
This information brief explains how RCRA corrective action and closure processes affect one another. It examines the similarities and differences between corrective action and closure, regulators' interests in RCRA facilities undergoing closure, and how the need to perform corrective action affects the closure of DOE's permitted facilities and interim status facilities
Simpson, Kyle
2014-01-01
No matter how much experience you have with JavaScript, odds are you don’t fully understand the language. This concise yet in-depth guide takes you inside scope and closures, two core concepts you need to know to become a more efficient and effective JavaScript programmer. You’ll learn how and why they work, and how an understanding of closures can be a powerful part of your development skillset.
Repository Closure and Sealing Approach
International Nuclear Information System (INIS)
A.T. Watkins
2000-01-01
The scope of this analysis will be to develop the conceptual design of the closure seals and their locations in the Subsurface Facilities. The design will be based on the recently established program requirements for transitioning to the Site Recommendation (SR) design as outlined by ''Approach to Implementing the Site Recommendation Baseline'' (Stroupe 2000) and the ''Monitored Geologic Repository Project Description Document'' (CRWMS M andO 1999b). The objective of this analysis will be to assist in providing a description for the Subsurface Facilities System Description Document, Section 2 and finally to document any conclusions reached in order to contribute and provide support to the SR. This analysis is at a conceptual level and is considered adequate to support the SR design. The final closure barriers and seals for the ventilation shafts, and the north and south ramps will require these openings to be permanently sealed to limit excessive air and water inflows and prevent human intrusion. The major tasks identified with closure in this analysis are: (1) Developing the overall subsurface seal layout and identifying design and operational interfaces for the Subsurface Facilities. (2) Summarizing the general site conditions and general rock characteristic with respect to seal location and describing the seal selected. (3) Identify seal construction materials, methodology of construction and strategic locations including design of the seal and plugs. (4) Discussing methods to prevent human intrusion
International Nuclear Information System (INIS)
Krivoruchenko, M.I.
1985-01-01
In chiral bag model an expression is obtained for the quark wave functions with account of color and pion interaction of quarks. The quadrupole moments of nonstrange hadrons are calculated. Quadrupole moment of nucleon isobar is found to be Q(Δ)=-6.3x10 -28 esub(Δ)(cm)sup(2). Fredictions of the chiral bag model are in strong disagreement with the non-relativistic quark model
Particle electric dipole moments
Pendlebury, J M
2000-01-01
Measurements of particle electric dipole moments (EDMs) continue to put powerful constraints on theories of T-symmetry and CP-symmetry violation, which form currently one of the most prominent fields in particle physics. EDM measurements have been concentrated on neutral systems such as the neutron and atoms and molecules. These measurements allow one to deduce, in turn, the electric dipole moments of the fundamental fermions, that is, the lighter leptons and quarks and also those of some heavy nuclei.
Moment Restriction-based Econometric Methods: An Overview
N. Kunitomo (Naoto); M.J. McAleer (Michael); Y. Nishiyama (Yoshihiko)
2010-01-01
textabstractMoment restriction-based econometric modelling is a broad class which includes the parametric, semiparametric and nonparametric approaches. Moments and conditional moments themselves are nonparametric quantities. If a model is specified in part up to some finite dimensional parameters,
Directory of Open Access Journals (Sweden)
Frederico Valle e Flister
2011-03-01
Full Text Available This work investigates the ability of the conditional CAPM to explain anomalous returns related to momentum, size and book-to-market effects using Lewellen and Nagel’s (2006 methodology in the Brazilian stock market. To this end we studied a sample of Bovespa’s stocks in a monthly basis from July 1995 to June 2008. The results indicate that only the book-to-market effect presents statistical significance. The conditional model, tested from time series of 12 months, also showed no significant gains in relation to the unconditional form. However, there are evidences that betas do vary over time, suggesting that the sample size on beta calculations may influence portfolio choices, i.e., the evidence of variation in betas over time means that analysis based on the CAPM should be cautious when using unconditional models.
Energy Technology Data Exchange (ETDEWEB)
Hanks, T.C.; Kanamori, H.
1979-05-10
The nearly conincident forms of the relations between seismic moment M/sub o/ and the magnitudes M/sub L/, M/sub s/, and M/sub w/ imply a moment magnitude scale M=2/3 log M/sub o/-10.7 which is uniformly valid for 3< or approx. =M/sub L/< or approx. = 7, 5 < or approx. =M/sub s/< or approx. =7 1/2 and M/sub w/> or approx. = 7 1/2.
International Nuclear Information System (INIS)
Overseth, O.E.
1981-01-01
The Fermilab Neutral Hyperon Beam Collaboration has measured the magnetic moments of Λ 0 , XI-neutral and XI-minus hyperons. With a recently published result for the Σ + hyperon, we now have precision measurements on the magnetic moments of six baryons. This allows a sensitive test of the quark model. The data are in qualitative agreement with the simple additive static quark model. Quantitatively however the data disagree with theoretical predictions by typically 15%. Several theoretical attempts to understand or remedy this discrepancy will be mentioned
International Nuclear Information System (INIS)
Kalen, D.D.; Mitchem, J.W.
1982-01-01
This invention relates to a closure mechanism for tubular irradiation surveillance specimen assembly holder used in nuclear reactors. The closure mechanism is composed of a latching member which includes a generally circular chamber with a plurality of elongated latches depending therefrom. The latching member circumscribes part of an actuator member which is disposed within the latching member so as to be axially movable. The axial movement of the actuator actuates positioning of the latches between positions in which the latches are locked and secured within the actuator member. Means, capable of being remotely manipulated, are provided to move the actuator in order to position the latches and load the articles within the tube
International Nuclear Information System (INIS)
Caldwell, T.B.
1997-01-01
A reducing grout has been developed for closing high level waste tanks at the Savannah River Site in Aiken, South Carolina. The grout has a low redox potential, which minimizes the mobility of Sr 90 , the radionuclide with the highest dose potential after closure. The grout also has a high pH which reduces the solubility of the plutonium isotopes. The grout has a high compressive strength and low permeability, which enhances its ability to limit the migration of contaminants after closure. The grout was designed and tested by Construction Technology Laboratories, Inc. Placement methods were developed by the Savannah River Site personnel
The verification of the Taylor-expansion moment method in solving aerosol breakage
Directory of Open Access Journals (Sweden)
Yu Ming-Zhou
2012-01-01
Full Text Available The combination of the method of moment, characterizing the particle population balance, and the computational fluid dynamics has been an emerging research issue in the studies on the aerosol science and on the multiphase flow science. The difficulty of solving the moment equation arises mainly from the closure of some fractal moment variables which appears in the transform from the non-linear integral-differential population balance equation to the moment equations. Within the Taylor-expansion moment method, the breakage-dominated Taylor-expansion moment equation is first derived here when the symmetric fragmentation mechanism is involved. Due to the high efficiency and the high precision, this proposed moment model is expected to become an important tool for solving population balance equations.
Pieters, Jurgen
2001-01-01
'Moments of Negotiation' offers the first book-length and indepth analysis of the New Historicist reading method, which the American Shakespeare-scolar Stephen Greenblatt introduced at the beginning of the 1980s. Ever since, Greenblatt has been hailed as the prime representative of this movement,
International Nuclear Information System (INIS)
Towner, I.S.; Khanna, F.C.
1984-01-01
Consideration of core polarization, isobar currents and meson-exchange processes gives a satisfactory understanding of the ground-state magnetic moments in closed-shell-plus (or minus)-one nuclei, A = 3, 15, 17, 39 and 41. Ever since the earliest days of the nuclear shell model the understanding of magnetic moments of nuclear states of supposedly simple configurations, such as doubly closed LS shells +-1 nucleon, has been a challenge for theorists. The experimental moments, which in most cases are known with extraordinary precision, show a small yet significant departure from the single-particle Schmidt values. The departure, however, is difficult to evaluate precisely since, as will be seen, it results from a sensitive cancellation between several competing corrections each of which can be as large as the observed discrepancy. This, then, is the continuing fascination of magnetic moments. In this contribution, we revisit the subjet principally to identify the role played by isobar currents, which are of much concern at this conference. But in so doing we warn quite strongly of the dangers of considering just isobar currents in isolation; equal consideration must be given to competing processes which in this context are the mundane nuclear structure effects, such as core polarization, and the more popular meson-exchange currents
Higgins, Chris
2014-01-01
In "The Humanist Moment," Chris Higgins sets out to recover a tenable, living humanism, rejecting both the version vilified by the anti-humanists and the one sentimentalized by the reactionary nostalgists. Rescuing humanism from such polemics is only the first step, as we find at least nine rival, contemporary definitions of humanism.…
International Nuclear Information System (INIS)
Payri, Raul; López, J. Javier; Martí-Aldaraví, Pedro; Giraldo, Jhoan S.
2016-01-01
Highlights: • LES in a non-reacting jet with co-flow is performed with OpenFoam. • Smagorinsky (SMAG) and One Equation Eddy (OEE) approaches are compared. • A turbulent pipe is used to generate and map coherent inlet turbulence structure. • Fluctuating inlet boundary condition requires much less computational cost. - Abstract: In this paper, the behavior and turbulence structure of a non-reacting jet with a co-flow stream is described by means of Large Eddy Simulations (LES) carried out with the computational tool OpenFoam. In order to study the influence of the sub-grid scale (SGS) model on the main flow statistics, Smagorinsky (SMAG) and One Equation Eddy (OEE) approaches are used to model the smallest scales involved in the turbulence of the jet. The impact of cell size and turbulent inlet boundary condition in resulting velocity profiles is analyzed as well. Four different tasks have been performed to accomplish these objectives. Firstly, the simulation of a turbulent pipe, which is necessary to generate and map coherent turbulence structure into the inlet of the non-reacting jet domain. Secondly, a structured mesh based on hexahedrons has been built for the jet and its co-flow. The third task consists on performing four different simulations. In those, mapping statistics from the turbulent pipe is compared with the use of fluctuating inlet boundary condition available in OpenFoam; OEE and SMAG approaches are contrasted; and the effect of changing cell size is investigated. Finally, as forth task, the obtained results are compared with experimental data. As main conclusions of this comparison, it has been proved that the fluctuating boundary condition requires much less computational cost, but some inaccuracies were found close to the nozzle. Also, both SGS models are capable to simulate this kind of jets with a co-flow stream with exactitude.
Evaluation of the Momentum Closure Schemes in MPAS-Ocean
Zhao, Shimei; Liu, Yudi; Liu, Wei
2018-04-01
In order to compare and evaluate the performances of the Laplacian viscosity closure, the biharmonic viscosity closure, and the Leith closure momentum schemes in the MPAS-Ocean model, a variety of physical quantities, such as the relative reference potential energy (RPE) change, the RPE time change rate (RPETCR), the grid Reynolds number, the root mean square (RMS) of kinetic energy, and the spectra of kinetic energy and enstrophy, are calculated on the basis of results of a 3D baroclinic periodic channel. Results indicate that: 1) The RPETCR demonstrates a saturation phenomenon in baroclinic eddy tests. The critical grid Reynolds number corresponding to RPETCR saturation differs between the three closures: the largest value is in the biharmonic viscosity closure, followed by that in the Laplacian viscosity closure, and that in the Leith closure is the smallest. 2) All three closures can effectively suppress spurious dianeutral mixing by reducing the grid Reynolds number under sub-saturation conditions of the RPETCR, but they can also damage certain physical processes. Generally, the damage to the rotation process is greater than that to the advection process. 3) The dissipation in the biharmonic viscosity closure is strongly dependent on scales. Most dissipation concentrates on small scales, and the energy of small-scale eddies is often transferred to large-scale kinetic energy. The viscous dissipation in the Laplacian viscosity closure is the strongest on various scales, followed by that in the Leith closure. Note that part of the small-scale kinetic energy is also transferred to large-scale kinetic energy in the Leith closure. 4) The characteristic length scale L and the dimensionless parameter D in the Leith closure are inherently coupled. The RPETCR is inversely proportional to the product of D and L. When the product of D and L is constant, both the simulated RPETCR and the inhibition of spurious dianeutral mixing are the same in all tests using the Leith
Professional Closure Beyond State Authorization
Directory of Open Access Journals (Sweden)
Gitte Sommer Harrits
2014-03-01
Full Text Available For decades, the Weberian approach to the study of professions has been strong, emphasizing state authorization and market monopolies as constituting what is considered a profession. Originally, however, the Weberian conception of closure, or the ways in which a profession is constituted and made separate, was broader. This article suggests a revision of the closure concept, integrating insights from Pierre Bourdieu, and conceptualizing professional closure as the intersection of social, symbolic and legal closure. Based on this revision, this article demonstrates how to apply such a concept in empirical studies. This is done by exploring social, symbolic and legal closure across sixteen professional degree programs. The analyses show a tendency for some overlap between different forms of closure, with a somewhat divergent pattern for legal closure. Results support the argument that we need to study these processes as an intersection of different sources of closure, including capital, lifestyles and discourse
DEFF Research Database (Denmark)
Sofka, Wolfgang; Torres Preto, Miguel; de Faria, Pedro
2014-01-01
We investigate the consequences of MNC subsidiary closures for employees who lose their jobs. In particular, we examine the extent to which the human capital that these employees acquired while employed by the MNC influences the wages they receive in their new jobs. We propose an employee...
DEFF Research Database (Denmark)
Lundahl, Mikela
2014-01-01
Heritage is a discourse that aims at closure. It fixates the narrative of the past through the celebration of specific material (or sometimes immaterial non-) ob-jects. It organizes temporality and construct events and freezes time. How does this unfold in the case of the UNESCO World Heritage si...
2013-01-01
On the occasion of the annual closure of CERN, there will be no mail distributed on Friday 20 December 2013 but mail will be collected in the morning. Nevertheless, you will still be able to bring your outgoing mail to Building 555-R-002 until 12 noon.
Ring closure in actin polymers
Energy Technology Data Exchange (ETDEWEB)
Sinha, Supurna, E-mail: supurna@rri.res.in [Raman Research Institute, Bangalore 560080 (India); Chattopadhyay, Sebanti [Doon University, Dehradun 248001 (India)
2017-03-18
We present an analysis for the ring closure probability of semiflexible polymers within the pure bend Worm Like Chain (WLC) model. The ring closure probability predicted from our analysis can be tested against fluorescent actin cyclization experiments. We also discuss the effect of ring closure on bend angle fluctuations in actin polymers. - Highlights: • Ring closure of biopolymers. • Worm like chain model. • Predictions for experiments.
A Quick Guide to Paravalvular Leak Closure
Gafoor, Sameer; Franke, Jennifer; Bertog, Stefan; Lam, Simon; Vaskelyte, Laura; Hofmann, Ilona; Matic, Predrag
2015-01-01
Paravalvular leak (PVL) is a seldomly covered aspect of structural heart disease. However, this is a condition that frequently presents after valvular replacement. This article will cover the diagnosising and treating PVL (i.e. imaging, access, and device selection). In addition, specific aspects of aortic and mitral PVL closure will be covered in this review. PMID:29588686
Transcatheter closure of patent ductus arteriosus: past, present and future.
Baruteau, Alban-Elouen; Hascoët, Sébastien; Baruteau, Julien; Boudjemline, Younes; Lambert, Virginie; Angel, Claude-Yves; Belli, Emre; Petit, Jérôme; Pass, Robert
2014-02-01
This review aims to describe the past history, present techniques and future directions in transcatheter treatment of patent ductus arteriosus (PDA). Transcatheter PDA closure is the standard of care in most cases and PDA closure is indicated in any patient with signs of left ventricular volume overload due to a ductus. In cases of left-to-right PDA with severe pulmonary arterial hypertension, closure may be performed under specific conditions. The management of clinically silent or very tiny PDAs remains highly controversial. Techniques have evolved and the transcatheter approach to PDA closure is now feasible and safe with current devices. Coils and the Amplatzer Duct Occluder are used most frequently for PDA closure worldwide, with a high occlusion rate and few complications. Transcatheter PDA closure in preterm or low-bodyweight infants remains a highly challenging procedure and further device and catheter design development is indicated before transcatheter closure is the treatment of choice in this delicate patient population. The evolution of transcatheter PDA closure from just 40 years ago with 18F sheaths to device delivery via a 3F sheath is remarkable and it is anticipated that further improvements will result in better safety and efficacy of transcatheter PDA closure techniques. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
CIRSE Vascular Closure Device Registry
Reekers, Jim A.; Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria
2011-01-01
Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. The CIRSE registry of closure devices
Crack closure, a literature study
Holmgren, M.
1993-08-01
In this report crack closure is treated. The state of the art is reviewed. Different empirical formulas for determining the crack closure are compared with each other, and their benefits are discussed. Experimental techniques for determining the crack closure stress are discussed, and some results from fatigue tests are also reported. Experimental data from the literature are reported.
Redefining the political moment
Directory of Open Access Journals (Sweden)
James Arvanitakis
2011-07-01
Full Text Available On 16 February 2003, more than half a million people gathered in Sydney, Australia, as part of a global anti-war protest aimed at stopping the impending invasion of Iraq by the then US Administration. It is difficult to estimate how many millions marched on the coordinated protest, but it was by far the largest mobilization of a generation. Walking and chanting on the streets of Sydney that day, it seemed that a political moment was upon us. In a culture that rarely embraces large scale activism, millions around Australian demanded to be heard. The message was clear: if you do not hear us, we would be willing to bring down a government. The invasion went ahead, however, with the then Australian government, under the leadership of John Howard, being one of the loudest and staunchest supporters of the Bush Administrations drive to war. Within 18 months, anti-war activists struggled to have a few hundred participants take part in anti-Iraq war rallies, and the Howard Government was comfortably re-elected for another term. The political moment had come and gone, with both social commentators and many members of the public looking for a reason. While the conservative media was often the focus of analysis, this paper argues that in a time of late capitalism, the political moment is hollowed out by ‘Politics’ itself. That is to say, that formal political processes (or ‘Politics’ undermine the political practices that people participate in everyday (or ‘politics’. Drawing on an ongoing research project focusing on democracy and young people, I discuss how the concept of ’politics‘ has been destabilised and subsequently, the political moment has been displaced. This displacement has led to a re-definition of ‘political action’ and, I argue, the emergence of a different type of everyday politics.
Czech Academy of Sciences Publication Activity Database
Suk, Tomáš; Flusser, Jan
2004-01-01
Roč. 26, č. 10 (2004), s. 1364-1367 ISSN 0162-8828 R&D Projects: GA ČR GA201/03/0675 Institutional research plan: CEZ:AV0Z1075907 Keywords : projective transform * moment invariants * object recognition Subject RIV: JD - Computer Applications, Robotics Impact factor: 4.352, year: 2004 http://library.utia.cas.cz/prace/20040112.pdf
Spins, moments and charge radii beyond $^{48}$Ca
Neyens, G; Rajabali, M M; Hammen, M; Blaum, K; Froemmgen, N E; Garcia ruiz, R F; Kreim, K D; Budincevic, I
Laser spectroscopy of $^{49-54}$Ca is proposed as a continuation of the experimental theme initiated with IS484 “Ground-state properties of K-isotopes from laser and $\\beta$-NMR spectroscopy” and expanded in INTC-I-117 “Moments, Spins and Charge Radii Beyond $^{48}$Ca.” It is anticipated that the charge radii of these isotopes can show strong evidence for the existence of a sub-shell closure at N=32 and could provide a first tentative investigation into the existence of a shell effect at N=34. Furthermore the proposed experiments will simultaneously provide model-independent measurements of the spins, magnetic moments and quadrupole moments of $^{51,53}$Ca permitting existing and future excitation spectra to be pinned to firm unambiguous ground states.
Summer season | Cafeteria closures
2013-01-01
Please note the following cafeteria closures over the summer season: Bldg. 54 closed from 29/07/2013 to 06/09/2013. Bldg. 13: closed from 13/07/2013 to 06/09/2013. Restaurant No. 2, table service (brasserie and restaurant): closed from 01/08/2013 to 06/09/2013. Bldg. 864: closed from 29/07/2013 to 06/09/2013. Bldg. 865: closed from 29/07/2013 to 06/09/2013.
Heavy quark and magnetic moment
International Nuclear Information System (INIS)
Mubarak, Ahmad; Jallu, M.S.
1979-01-01
The magnetic moments and transition moments of heavy hadrons including the conventional particles are obtained under the SU(5) truth symmetry scheme. To this end state vectors are defined and the quark additivity principle is taken into account. (author)
Moment methods for nonlinear maps
International Nuclear Information System (INIS)
Pusch, G.D.; Atomic Energy of Canada Ltd., Chalk River, ON
1993-01-01
It is shown that Differential Algebra (DA) may be used to push moments of distributions through a map, at a computational cost per moment comparable to pushing a single particle. The algorithm is independent of order, and whether or not the map is symplectic. Starting from the known result that moment-vectors transform linearly - like a tensor - even under a nonlinear map, I suggest that the form of the moment transformation rule indicates that the moment-vectors are elements of the dual to DA-vector space. I propose several methods of manipulating moments and constructing invariants using DA. I close with speculations on how DA might be used to ''close the circle'' to solve the inverse moment problem, yielding an entirely DA-and-moment-based space-charge code. (Author)
Energy Technology Data Exchange (ETDEWEB)
Zou, Ling [Idaho National Lab. (INL), Idaho Falls, ID (United States); Berry, R. A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Martineau, R. C. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Andrs, D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zhang, H. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hansel, J. E. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sharpe, J. P. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Johns, Russell C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2017-04-01
The RELAP-7 code is the next generation nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). The code is based on the INL’s modern scientific software development framework, MOOSE (Multi-Physics Object Oriented Simulation Environment). The overall design goal of RELAP-7 is to take advantage of the previous thirty years of advancements in computer architecture, software design, numerical integration methods, and physical models. The end result will be a reactor systems analysis capability that retains and improves upon RELAP5’s and TRACE’s capabilities and extends their analysis capabilities for all reactor system simulation scenarios. The RELAP-7 code utilizes the well-posed 7-equation two-phase flow model for compressible two-phase flow. Closure models used in the TRACE code has been reviewed and selected to reflect the progress made during the past decades and provide a basis for the colure correlations implemented in the RELAP-7 code. This document provides a summary on the closure correlations that are currently implemented in the RELAP-7 code. The closure correlations include sub-grid models that describe interactions between the fluids and the flow channel, and interactions between the two phases.
Urethrovaginal fistula closure.
Clifton, Marisa M; Goldman, Howard B
2017-01-01
In the developed world, urethrovaginal fistulas are most the likely the result of iatrogenic injury. These fistulas are quite rare. Proper surgical repair requires careful dissection and tension-free closure. The objective of this video is to demonstrate the identification and surgical correction of an urethrovaginal fistula. The case presented is of a 59-year-old woman with a history of pelvic organ prolapse and symptomatic stress urinary incontinence who underwent vaginal hysterectomy, anterior colporrhaphy, posterior colporrhaphy, and synthetic sling placement. Postoperatively, she developed a mesh extrusion and underwent sling excision. After removal of her synthetic sling, she began to experience continuous urinary incontinence. Physical examination and cystourethroscopy demonstrated an urethrovaginal fistula at the midurethra. Options were discussed and the patient wished to undergo transvaginal fistula repair. The urethrovaginal fistula was intubated with a Foley catheter. The fistula tract was isolated and removed. The urethra was then closed with multiple tension-free layers. This video demonstrates several techniques for identifying and subsequently repairing an urethrovaginal fistula. Additionally, it demonstrates the importance of tension-free closure. Urethrovaginal fistulas are rare. They should be repaired with careful dissection and tension-free closure.
Review on improved seismic imaging with closure phase
Schuster, Gerard T.; Huang, Yunsong; Hanafy, Sherif M.; Zhou, Min; Yu, Jianhua; Alhagan, Ola; Dai, Wei
2014-01-01
remedy this problem, we comprehensively reviewed inverting differential traveltimes that satisfied the closure-phase condition. The result is that the source and receiver statics are completely eliminated in the data and velocities far from the target do
Paul Callaghan luminous moments
Callaghan, Paul
2013-01-01
Acknowledged internationally for his ground-breaking scientific research in the field of magnetic resonance, Sir Paul Callaghan was a scientist and visionary with a rare gift for promoting science to a wide audience. He was named New Zealander of the Year in 2011. His death in early 2012 robbed New Zealand of an inspirational leader. Paul Callaghan: Luminous Moments brings together some of his most significant writing. Whether he describes his childhood in Wanganui, reflects on discovering the beauty of science, sets out New Zealand's future potential or discusses the experience of fa
Neutron Electric Dipole Moment
International Nuclear Information System (INIS)
Mischke, R.E.
2003-01-01
The status of experiments to measure the electric dipole moment of the neutron is presented and the planned experiment at Los Alamos is described. The goal of this experiment is an improvement in sensitivity of a factor of 50 to 100 over the current limit. It has the potential to reveal new sources of T and CP violation and to challenge calculations that propose extensions to the Standard Model. The experiment employs several advances in technique to reach its goals and the feasibility of meeting these technical challenges is currently under study
Pit closures - effects and alternatives
Energy Technology Data Exchange (ETDEWEB)
Stott, A G
1987-02-01
During the last decade, British Coal has closed around 100 mines. This article illustrates the effect of pit closures on the colliery's workforce, and the local community and its economy. Working conditions at Newmarket Colliery and the Selby coalfield are compared within the context of British Coal's national transfer market. British Coal's transfer benefits include resettlement payments and mortgage subsidies. The job creation venture of British Coal Enterprise Ltd. has helped to create over 3700 new jobs in 264 projects, involving a total investment of 38 M pounds sterling. The article also discusses deputies' qualifications and prospects for recently qualified management staff, and gives a comparison of losses suffered by the different mining unions.
Closure and ratio correlation analysis of lunar chemical and grain size data
Butler, J. C.
1976-01-01
Major element and major element plus trace element analyses were selected from the lunar data base for Apollo 11, 12 and 15 basalt and regolith samples. Summary statistics for each of the six data sets were compiled, and the effects of closure on the Pearson product moment correlation coefficient were investigated using the Chayes and Kruskal approximation procedure. In general, there are two types of closure effects evident in these data sets: negative correlations of intermediate size which are solely the result of closure, and correlations of small absolute value which depart significantly from their expected closure correlations which are of intermediate size. It is shown that a positive closure correlation will arise only when the product of the coefficients of variation is very small (less than 0.01 for most data sets) and, in general, trace elements in the lunar data sets exhibit relatively large coefficients of variation.
Directory of Open Access Journals (Sweden)
Marc eWittmann
2011-10-01
Full Text Available It has been suggested that perception and action can be understood as evolving in temporal epochs or sequential processing units. Successive events are fused into units forming a unitary experience or ‘psychological present’. Studies have identified several temporal integration levels on different time scales which are fundamental for our understanding of behaviour and subjective experience. In recent literature concerning the philosophy and neuroscience of consciousness these separate temporal processing levels are not always precisely distinguished. Therefore, empirical evidence from psychophysics and neuropsychology on these distinct temporal processing levels is presented and discussed within philosophical conceptualizations of time experience. On an elementary level, one can identify a functional moment, a basic temporal building block of perception in the range of milliseconds that defines simultaneity and succession. Below a certain threshold temporal order is not perceived, individual events are processed as co-temporal. On a second level, an experienced moment, which is based on temporal integration of up to a few seconds, has been reported in many qualitatively different experiments in perception and action. It has been suggested that this segmental processing mechanism creates temporal windows that provide a logistical basis for conscious representation and the experience of nowness. On a third level of integration, continuity of experience is enabled by working-memory in the range of multiple seconds allowing the maintenance of cognitive operations and emotional feelings, leading to mental presence, a temporal window of an individual’s experienced presence.
Madadi-Kandjani, E.; Fox, R. O.; Passalacqua, A.
2017-06-01
An extended quadrature method of moments using the β kernel density function (β -EQMOM) is used to approximate solutions to the evolution equation for univariate and bivariate composition probability distribution functions (PDFs) of a passive scalar for binary and ternary mixing. The key element of interest is the molecular mixing term, which is described using the Fokker-Planck (FP) molecular mixing model. The direct numerical simulations (DNSs) of Eswaran and Pope ["Direct numerical simulations of the turbulent mixing of a passive scalar," Phys. Fluids 31, 506 (1988)] and the amplitude mapping closure (AMC) of Pope ["Mapping closures for turbulent mixing and reaction," Theor. Comput. Fluid Dyn. 2, 255 (1991)] are taken as reference solutions to establish the accuracy of the FP model in the case of binary mixing. The DNSs of Juneja and Pope ["A DNS study of turbulent mixing of two passive scalars," Phys. Fluids 8, 2161 (1996)] are used to validate the results obtained for ternary mixing. Simulations are performed with both the conditional scalar dissipation rate (CSDR) proposed by Fox [Computational Methods for Turbulent Reacting Flows (Cambridge University Press, 2003)] and the CSDR from AMC, with the scalar dissipation rate provided as input and obtained from the DNS. Using scalar moments up to fourth order, the ability of the FP model to capture the evolution of the shape of the PDF, important in turbulent mixing problems, is demonstrated. Compared to the widely used assumed β -PDF model [S. S. Girimaji, "Assumed β-pdf model for turbulent mixing: Validation and extension to multiple scalar mixing," Combust. Sci. Technol. 78, 177 (1991)], the β -EQMOM solution to the FP model more accurately describes the initial mixing process with a relatively small increase in computational cost.
Nevada Test Site closure program
International Nuclear Information System (INIS)
Shenk, D.P.
1994-08-01
This report is a summary of the history, design and development, procurement, fabrication, installation and operation of the closures used as containment devices on underground nuclear tests at the Nevada Test Site. It also addresses the closure program mothball and start-up procedures. The Closure Program Document Index and equipment inventories, included as appendices, serve as location directories for future document reference and equipment use
DEFF Research Database (Denmark)
de Faria, Pedro; Sofka, Wolfgang; Torres Preto, Miguel
2013-01-01
We investigate the consequences of MNC subsidiary closures for employees who lose their jobs. We ask to what degree the foreign knowledge that they were exposed to is valued in their new job. We argue theoretically that this foreign knowledge is both valuable and not readily available in the host...... country but is also distant and therefore difficult to absorb. We predict an inverse u-shaped relationship between the exposure to foreign knowledge and the salary in the new job. We empirically support our predictions for a sample of almost 140,000 affected employees in Portugal from 2002 to 2009....
Approximating distributions from moments
Pawula, R. F.
1987-11-01
A method based upon Pearson-type approximations from statistics is developed for approximating a symmetric probability density function from its moments. The extended Fokker-Planck equation for non-Markov processes is shown to be the underlying foundation for the approximations. The approximation is shown to be exact for the beta probability density function. The applicability of the general method is illustrated by numerous pithy examples from linear and nonlinear filtering of both Markov and non-Markov dichotomous noise. New approximations are given for the probability density function in two cases in which exact solutions are unavailable, those of (i) the filter-limiter-filter problem and (ii) second-order Butterworth filtering of the random telegraph signal. The approximate results are compared with previously published Monte Carlo simulations in these two cases.
Influence of fatigue crack wake length and state of stress on crack closure
Telesman, Jack; Fisher, Douglas M.
1988-01-01
The location of crack closure with respect to crack wake and specimen thickness under different loading conditions was determined. The rate of increase of K sub CL in the crack wake was found to be significantly higher for plasticity induced closure in comparison to roughness induced closure. Roughness induced closure was uniform throughout the thickness of the specimen while plasticity induced closure levels were 50 percent higher in the near surface region than in the midthickness. The influence of state of stress on low-high load interaction effects was also examined. Load interaction effects differed depending upon the state of stress and were explained in terms of delta K sub eff.
International Nuclear Information System (INIS)
Anon.
1995-01-01
Discussions on the future of the Chernobyl nuclear plant between the Ukrainian government, the Group of Seven Industrial nations (GT) and the European Union (EU) are summarized. At the G7 meeting, a timetable for the closure of the entire station by 2000 was presented by Ukrainian officials. The timetable depends on financial commitments from Western governments. Without these, the project would take 10 to 15 years. Following this meeting, which took place on 16-17th May 1995. EU finance ministers authorized release of a ECU 85 million loan. On 23 May, the European Parliament's Committee on Research, Technology and Energy held a public hearing on the Chernobyl station. The primary topic was a feasibility study on the clean-up of Chernobyl 4 and plans for the sarcophagus. Other matters discussed included the effect of the delays and indecision in settling the plants's future. Safety improvements being made to other RBMKs were not being carried out at Chernobyl because of the expected closure. The replacement of the power now supplied to the Ukraine by the Chernobyl reactors is also an issue. The solution favoured by the Ukraine is to being on-line three VVER-1000s that are currently close to completion. Western governments find this solution difficult to accept, however. (UK)
An 18 Moments Model for Dense Gases: Entropy and Galilean Relativity Principles without Expansions
Directory of Open Access Journals (Sweden)
M. Cristina Carrisi
2015-01-01
Full Text Available The 14 moments model for dense gases, introduced in the last few years by Arima, Taniguchi, Ruggeri and Sugiyama, is here extended up to 18 moments. They have found the closure of the balance equations up to a finite order with respect to equilibrium; it is also possible to impose for that model the entropy and Galilean relativity principles up to whatever order with respect to equilibrium, but by using Taylor’s expansion. Here, the exact solution is found, without expansions, but a bigger number of moments has to be considered and reasons will be shown suggesting that this number is at least 18.
Tight closure and vanishing theorems
International Nuclear Information System (INIS)
Smith, K.E.
2001-01-01
Tight closure has become a thriving branch of commutative algebra since it was first introduced by Mel Hochster and Craig Huneke in 1986. Over the past few years, it has become increasingly clear that tight closure has deep connections with complex algebraic geometry as well, especially with those areas of algebraic geometry where vanishing theorems play a starring role. The purpose of these lectures is to introduce tight closure and to explain some of these connections with algebraic geometry. Tight closure is basically a technique for harnessing the power of the Frobenius map. The use of the Frobenius map to prove theorems about complex algebraic varieties is a familiar technique in algebraic geometry, so it should perhaps come as no surprise that tight closure is applicable to algebraic geometry. On the other hand, it seems that so far we are only seeing the tip of a large and very beautiful iceberg in terms of tight closure's interpretation and applications to algebraic geometry. Interestingly, although tight closure is a 'characteristic p' tool, many of the problems where tight closure has proved useful have also yielded to analytic (L2) techniques. Despite some striking parallels, there had been no specific result directly linking tight closure and L∼ techniques. Recently, however, the equivalence of an ideal central to the theory of tight closure was shown to be equivalent to a certain 'multiplier ideal' first defined using L2 methods. Presumably, deeper connections will continue to emerge. There are two main types of problems for which tight closure has been helpful: in identifying nice structure and in establishing uniform behavior. The original algebraic applications of tight closure include, for example, a quick proof of the Hochster-Roberts theorem on the Cohen-Macaulayness of rings of invariants, and also a refined version of the Brianqon-Skoda theorem on the uniform behaviour of integral closures of powers of ideals. More recent, geometric
Extension of moment projection method to the fragmentation process
International Nuclear Information System (INIS)
Wu, Shaohua; Yapp, Edward K.Y.; Akroyd, Jethro; Mosbach, Sebastian; Xu, Rong; Yang, Wenming; Kraft, Markus
2017-01-01
The method of moments is a simple but efficient method of solving the population balance equation which describes particle dynamics. Recently, the moment projection method (MPM) was proposed and validated for particle inception, coagulation, growth and, more importantly, shrinkage; here the method is extended to include the fragmentation process. The performance of MPM is tested for 13 different test cases for different fragmentation kernels, fragment distribution functions and initial conditions. Comparisons are made with the quadrature method of moments (QMOM), hybrid method of moments (HMOM) and a high-precision stochastic solution calculated using the established direct simulation algorithm (DSA) and advantages of MPM are drawn.
Extension of moment projection method to the fragmentation process
Energy Technology Data Exchange (ETDEWEB)
Wu, Shaohua [Department of Mechanical Engineering, National University of Singapore, Engineering Block EA, Engineering Drive 1, 117576 (Singapore); Yapp, Edward K.Y.; Akroyd, Jethro; Mosbach, Sebastian [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge, CB2 3RA (United Kingdom); Xu, Rong [School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 (Singapore); Yang, Wenming [Department of Mechanical Engineering, National University of Singapore, Engineering Block EA, Engineering Drive 1, 117576 (Singapore); Kraft, Markus, E-mail: mk306@cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge, CB2 3RA (United Kingdom); School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 (Singapore)
2017-04-15
The method of moments is a simple but efficient method of solving the population balance equation which describes particle dynamics. Recently, the moment projection method (MPM) was proposed and validated for particle inception, coagulation, growth and, more importantly, shrinkage; here the method is extended to include the fragmentation process. The performance of MPM is tested for 13 different test cases for different fragmentation kernels, fragment distribution functions and initial conditions. Comparisons are made with the quadrature method of moments (QMOM), hybrid method of moments (HMOM) and a high-precision stochastic solution calculated using the established direct simulation algorithm (DSA) and advantages of MPM are drawn.
International Nuclear Information System (INIS)
Wang, Liang; Germaschewski, K.; Hakim, Ammar H.; Bhattacharjee, A.
2015-01-01
We introduce an extensible multi-fluid moment model in the context of collisionless magnetic reconnection. This model evolves full Maxwell equations and simultaneously moments of the Vlasov-Maxwell equation for each species in the plasma. Effects like electron inertia and pressure gradient are self-consistently embedded in the resulting multi-fluid moment equations, without the need to explicitly solving a generalized Ohm's law. Two limits of the multi-fluid moment model are discussed, namely, the five-moment limit that evolves a scalar pressures for each species and the ten-moment limit that evolves the full anisotropic, non-gyrotropic pressure tensor for each species. We first demonstrate analytically and numerically that the five-moment model reduces to the widely used Hall magnetohydrodynamics (Hall MHD) model under the assumptions of vanishing electron inertia, infinite speed of light, and quasi-neutrality. Then, we compare ten-moment and fully kinetic particle-in-cell (PIC) simulations of a large scale Harris sheet reconnection problem, where the ten-moment equations are closed with a local linear collisionless approximation for the heat flux. The ten-moment simulation gives reasonable agreement with the PIC results regarding the structures and magnitudes of the electron flows, the polarities and magnitudes of elements of the electron pressure tensor, and the decomposition of the generalized Ohm's law. Possible ways to improve the simple local closure towards a nonlocal fully three-dimensional closure are also discussed
Directory of Open Access Journals (Sweden)
Jay Foster
2015-11-01
Full Text Available At least two recent collections of essays – Postmodernism and the Enlightenment (2001 and What’s Left of Enlightenment?: A Postmodern Question (2001 – have responded to postmodern critiques of Enlightenment by arguing that Enlightenment philosophes themselves embraced a number of post-modern themes. This essay situates Kant’s essay Was ist Aufklärung (1784 in the context of this recent literature about the appropriate characterization of modernity and the Enlightenment. Adopting an internalist reading of Kant’s Aufklärung essay, this paper observes that Kant is surprisingly ambivalent about who might be Enlightened and unspecific about when Enlightenment might be achieved. The paper argues that this is because Kant is concerned less with elucidating his concept of Enlightenment and more with characterizing a political condition that might provide the conditions for the possibility of Enlightenment. This paper calls this political condition modernity and it is achieved when civil order can be maintained alongside fractious and possibly insoluble public disagreement about matters of conscience, including the nature and possibility of Enlightenment. Thus, the audience for the Aufklärung essay is not the tax collector, soldier or clergyman, but rather the sovereign. Kant enjoins and advises the prince that discord and debate about matters of conscience need not entail any political unrest or upheaval. It is in this restricted (Pocockian sense that the Enlightenment essay is Kant’s Machiavellian moment.
Guidance for closure of existing DOE LLW disposal sites
International Nuclear Information System (INIS)
Blanchfield, L.
1987-01-01
During FY 1986, a closure guidance document was developed. The purpose of this document is to provide guidance in support of DOE Order 5820.2 to site operating contractors for the stabilization and closure of existing low-level waste (LLW) shallow land disposal sites at US Department of Energy (DOE) facilities. Guidance is provided to aid operators in placing existing LLW sites in a closed conditions, i.e., a condition in which a nonoperational site meets postclosure performance requirements and can be shown, within a high degree of confidence, to perform as anticipated in the future, under the most cost-effective maintenance approach. Guidance is based on the philosophy that closure should be planned and performed using a systems approach. Plans for FY 1987 call for revision of the document to incorporate more information on closure of LLW sites also containing radioactive mixed waste and/or transuranic waste. 4 references, 3 figures, 2 tables
Moment invariants for particle beams
International Nuclear Information System (INIS)
Lysenko, W.P.; Overley, M.S.
1988-01-01
The rms emittance is a certain function of second moments in 2-D phase space. It is preserved for linear uncoupled (1-D) motion. In this paper, the authors present new functions of moments that are invariants for coupled motion. These invariants were computed symbolically using a computer algebra system. Possible applications for these invariants are discussed. Also, approximate moment invariants for nonlinear motion are presented
International Nuclear Information System (INIS)
Kalen, D.D.; Mitchem, J.W.
1981-01-01
An apparatus is provided for closing the bore of a tube and releasably securing articles within the tube under longitudinal load. A latching member has a cylindrical section and several circumferentially-spaced elongated latches hanging down from one end of the cylinder. An elongated actuator has integral cam and spline and is partly located within the latch with the cam radially contacting the latches and the spline projecting into the circumferential spaces between the latches. The actuator is axially movable between a position in which the latches are locked to the tube walls and a position in which the latches are secured from contact with the tube walls. Means are provided for axially moving the actuator such that the cam positions the latches; and means are also provided for engaging the articles within the tube. The closure is particularly applicable to tubular irradiation surveillance specimen assembly holders used in reactors
Airport Movement Area Closure Planner, Phase I
National Aeronautics and Space Administration — This SBIR research develops an automation tool improving temporary and permanent runway closure management. The Movement Area Closure Planner (MACP) provides airport...
Elliptic blending model : A new near-wall Reynolds-stress turbulence closure
Manceau, R.; Hanjali?, K.
2001-01-01
A new approach to modeling the effects of a solid wall in one-point second-moment (Reynolds-stress) turbulence closures is presented. The model is based on the relaxation of an inhomogeneous (near-wall) formulation of the pressure–strain tensor towards the chosen conventional homogeneous
Spins, Electromagnetic Moments, and Isomers of 107-129Cd
Yordanov, D T; Bieron, J; Bissell, M L; Blaum, K; Budincevic, I; Fritzsche, S; Frommgen, N; Georgiev, G; Geppert, Ch; Hammen, M; Kowalska, M; Kreim, K; Krieger, A; Neugart, R; Nortershauser, W; Papuga, J; Schmidt, S
2013-01-01
The neutron-rich isotopes of cadmium up to the N=82 shell closure have been investigated by high-resolution laser spectroscopy. Deep-UV excitation at 214.5 nm and radioactive-beam bunching provided the required experimental sensitivity. Long-lived isomers are observed in 127Cd and 129Cd for the first time. One essential feature of the spherical shell model is unambiguously confirmed by a linear increase of the 11/2- quadrupole moments. Remarkably, this mechanism is found to act well beyond the h11/2 shell.
Face recognition using Krawtchouk moment
Indian Academy of Sciences (India)
Zernike moment to enhance the discriminant nature (Pang et al 2006). ... was proposed which is partially invariant to changes in the local image samples, ... tigate the Krawtchouk discrete orthogonal moment-based feature ..... in scale have been achieved by changing the distance between the person and the video camera.
Variational approach to magnetic moments
Energy Technology Data Exchange (ETDEWEB)
Lipparini, E; Stringari, S; Traini, M [Dipartimento di Matematica e Fisica, Libera Universita di Trento, Italy
1977-11-07
Magnetic moments in nuclei with a spin unsaturated core plus or minus an extra nucleon have been studied using a restricted Hartree-Fock approach. The method yields simple explicit expressions for the deformed ground state and for magnetic moments. Different projection techniques of the HF scheme have been discussed and compared with perturbation theory.
On fractional Fourier transform moments
Alieva, T.; Bastiaans, M.J.
2000-01-01
Based on the relation between the ambiguity function represented in a quasi-polar coordinate system and the fractional power spectra, the fractional Fourier transform moments are introduced. Important equalities for the global second-order fractional Fourier transform moments are derived and their
Neutron Electric Dipole Moment Experiments
Peng, Jen-Chieh
2008-01-01
The neutron electric dipole moment (EDM) provides unique information on CP violation and physics beyond the Standard Model. We first review the history of experimental searches for neutron electric dipole moment. The status of future neutron EDM experiments, including experiments using ultra-cold neutrons produced in superfluid helium, will then be presented.
Vingerhoets, P; Avgoulea, M; Billowes, J; Bissell, M L; Blaum, K; Brown, B A; Cheal, B; De Rydt, M; Forest, D H; Geppert, Ch; Honma, M; Kowalska, M; Kramer, J; Krieger, A; Mane, E; Neugart, R; Neyens, G; Nortershauser, W; Otsuka, T; Schug, M; Stroke, H H; Tungate, G; Yordanov, D T
2010-01-01
Measurements of the ground-state nuclear spins, magnetic and quadrupole moments of the copper isotopes from 61Cu up to 75Cu are reported. The experiments were performed at the ISOLDE facility, using the technique of collinear laser spectroscopy. The trend in the magnetic moments between the N=28 and N=50 shell closures is reasonably reproduced by large-scale shell-model calculations starting from a 56Ni core. The quadrupole moments reveal a strong polarization of the underlying Ni core when the neutron shell is opened, which is however strongly reduced at N=40 due to the parity change between the $pf$ and $g$ orbits. No enhanced core polarization is seen beyond N=40. Deviations between measured and calculated moments are attributed to the softness of the 56Ni core and weakening of the Z=28 and N=28 shell gaps.
Decontamination and inspection plan for Phase 3 closure of the 300 area waste acid treatment system
International Nuclear Information System (INIS)
LUKE, S.N.
1999-01-01
This decontamination and inspection plan (DIP) describes decontamination and verification activities in support of Phase 3 closure of the 300 Area Waste Acid Treatment System (WATS). Phase 3 is the third phase of three WATS closure phases. Phase 3 attains clean closure conditions for WATS portions of the 334 and 311 Tank Farms (TF) and the 333 and 303-F Buildings. This DIP also describes designation and management of waste and debris generated during Phase 3 closure activities. Information regarding Phase 1 and Phase 2 for decontamination and verification activities closure can be found in WHC-SD-ENV-AP-001 and HNF-1784, respectively. This DIP is provided as a supplement to the closure plan (DOE/RL-90-11). This DIP provides the documentation for Ecology concurrence with Phase 3 closure methods and activities. This DIP is intended to provide greater detail than is contained in the closure plan to satisfy Ecology Dangerous Waste Regulations, Washington Administrative Code (WAC) 173-303-610 requirement that closure documents describe the methods for removing, transporting, storing, and disposing of all dangerous waste at the unit. The decontamination and verification activities described in this DIP are based on the closure plan and on agreements reached between Ecology and the U.S. Department of Energy, Richland Operations Office (DOE-RL) during Phase 3 closure activity workshops and/or project manager meetings (PMMs)
International Nuclear Information System (INIS)
1994-01-01
This report has been prepared to satisfy Section 3156(b) of Public Law 101-189 (Reports in Connection with Permanent Closures of Department of Energy Defense Nuclear Facilities), which requires submittal of a Closure Report to Congress by the Secretary of Energy upon the permanent cessation of production operations at a US Department of Energy (DOE) defense nuclear facility (Watkins 1991). This closure report provides: (1) A complete survey of the environmental problems at the facility; (2) Budget quality data indicating the cost of environmental restoration and other remediation and cleanup efforts at the facility; (3) A proposed cleanup schedule
Energy Technology Data Exchange (ETDEWEB)
1994-01-01
This report has been prepared to satisfy Section 3156(b) of Public Law 101-189 (Reports in Connection with Permanent Closures of Department of Energy Defense Nuclear Facilities), which requires submittal of a Closure Report to Congress by the Secretary of Energy upon the permanent cessation of production operations at a US Department of Energy (DOE) defense nuclear facility (Watkins 1991). This closure report provides: (1) A complete survey of the environmental problems at the facility; (2) Budget quality data indicating the cost of environmental restoration and other remediation and cleanup efforts at the facility; (3) A proposed cleanup schedule.
Evaluation of Container Closure System Integrity for Frozen Storage Drug Products.
Nieto, Alejandra; Roehl, Holger; Brown, Helen; Nikoloff, Jonas; Adler, Michael; Mahler, Hanns-Christian
2016-01-01
Sometimes, drug product for parenteral administration is stored in a frozen state (e.g., -20 °C or -80 °C), particularly during early stages of development of some biotech molecules in order to provide sufficient stability. Shipment of frozen product could potentially be performed in the frozen state, yet possibly at different temperatures, for example, using dry ice (-80 °C). Container closure systems of drug products usually consist of a glass vial, rubber stopper, and an aluminum crimped cap. In the frozen state, the glass transition temperature (Tg) of commonly used rubber stoppers is between -55 and -65 °C. Below their Tg, rubber stoppers are known to lose their elastic properties and become brittle, and thus potentially fail to maintain container closure integrity in the frozen state. Leaks during frozen temperature storage and transportation are likely to be transient, yet, can possibly risk container closure integrity and lead to microbial contamination. After thawing, the rubber stopper is supposed to re-seal the container closure system. Given the transient nature of the possible impact on container closure integrity in the frozen state, typical container closure integrity testing methods (used at room temperature conditions) are unable to evaluate and thus confirm container closure integrity in the frozen state. Here we present the development of a novel method (thermal physical container closure integrity) for direct assessment of container closure integrity by a physical method (physical container closure integrity) at frozen conditions, using a modified He leakage test. In this study, different container closure systems were evaluated with regard to physical container closure integrity in the frozen state to assess the suitability of vial/stopper combinations and were compared to a gas headspace method. In summary, the thermal physical container closure integrity He leakage method was more sensitive in detecting physical container closure
Interferometric Imaging Directly with Closure Phases and Closure Amplitudes
Chael, Andrew A.; Johnson, Michael D.; Bouman, Katherine L.; Blackburn, Lindy L.; Akiyama, Kazunori; Narayan, Ramesh
2018-04-01
Interferometric imaging now achieves angular resolutions as fine as ∼10 μas, probing scales that are inaccessible to single telescopes. Traditional synthesis imaging methods require calibrated visibilities; however, interferometric calibration is challenging, especially at high frequencies. Nevertheless, most studies present only a single image of their data after a process of “self-calibration,” an iterative procedure where the initial image and calibration assumptions can significantly influence the final image. We present a method for efficient interferometric imaging directly using only closure amplitudes and closure phases, which are immune to station-based calibration errors. Closure-only imaging provides results that are as noncommittal as possible and allows for reconstructing an image independently from separate amplitude and phase self-calibration. While closure-only imaging eliminates some image information (e.g., the total image flux density and the image centroid), this information can be recovered through a small number of additional constraints. We demonstrate that closure-only imaging can produce high-fidelity results, even for sparse arrays such as the Event Horizon Telescope, and that the resulting images are independent of the level of systematic amplitude error. We apply closure imaging to VLBA and ALMA data and show that it is capable of matching or exceeding the performance of traditional self-calibration and CLEAN for these data sets.
Neglected ends: clinical ethics consultation and the prospects for closure.
Fiester, Autumn
2015-01-01
Clinical ethics consultations (CECs) are sometimes deemed complete at the moment when the consultants make a recommendation. In CECs that involve actual ethical conflict, this view of a consult's endpoint runs the risk of overemphasizing the conflict's resolution at the expense of the consult's process, which can have deleterious effects on the various parties in the conflict. This overly narrow focus on reaching a decision or recommendation in consults that involve profound moral disagreement can result in two types of adverse, lingering sequelae: moral distress or negative moral emotions. The problem, succinctly named, is that such consults have insufficient "closure" for patients, families, and providers. To promote closure, and avoid the ills of moral distress and the moral emotions, I argue that CECs need to prioritize assisted conversation between the different stakeholders in these conflicts, what is often referred to as "bioethics mediation."
International Nuclear Information System (INIS)
Fuenkajorn, K.; Daemen, J.J.K.
1988-12-01
Constitutive law parameters are determined from salt behavior characterization experiments. The results are applied to predict creep (time-dependent) closure of boreholes in salt specimens subjected to various loading configurations. Rheological models (linear and nonlinear viscoelastic and viscoplastic models), empirical models, and physical theory models have been formulated from the results of uniaxial creep tests, strain and stress rate controlled uniaxial tests, constant strain rate triaxial tests, cyclic loading tests, and seismic velocity measurements. Analytical solutions for a thick-walled cylinder subjected to internal and external pressures and for a circular hole in an infinite plate subjected to a biaxial or uniaxial stressfield have been derived from each of the linear viscoelastic models and from one of the empirical laws. The experimental results indicate that the salt samples behave as an elastic-viscoplastic material. The elastic behavior tends to be linear and time-independent. The plastic deformation is time-dependent. The stress increment to strain rate increment ratio gradually decreases as the stress level increases. The transient potential creep law seems to give the simplest satisfactory governing equation describing the viscoplastic behavior of salt during the transient phase. 204 refs., 27 figs., 29 tabs
Understanding the basis of space closure in Orthodontics for a more efficient orthodontic treatment.
Ribeiro, Gerson Luiz Ulema; Jacob, Helder B
2016-01-01
Space closure is one of the most challenging processes in Orthodontics and requires a solid comprehension of biomechanics in order to avoid undesirable side effects. Understanding the biomechanical basis of space closure better enables clinicians to determine anchorage and treatment options. In spite of the variety of appliance designs, space closure can be performed by means of friction or frictionless mechanics, and each technique has its advantages and disadvantages. Friction mechanics or sliding mechanics is attractive because of its simplicity; the space site is closed by means of elastics or coil springs to provide force, and the brackets slide on the orthodontic archwire. On the other hand, frictionless mechanics uses loop bends to generate force to close the space site, allowing differential moments in the active and reactive units, leading to a less or more anchorage control, depending on the situation. This article will discuss various theoretical aspects and methods of space closure based on biomechanical concepts.
Understanding the basis of space closure in Orthodontics for a more efficient orthodontic treatment
Directory of Open Access Journals (Sweden)
Gerson Luiz Ulema Ribeiro
2016-04-01
Full Text Available ABSTRACT Introduction: Space closure is one of the most challenging processes in Orthodontics and requires a solid comprehension of biomechanics in order to avoid undesirable side effects. Understanding the biomechanical basis of space closure better enables clinicians to determine anchorage and treatment options. In spite of the variety of appliance designs, space closure can be performed by means of friction or frictionless mechanics, and each technique has its advantages and disadvantages. Friction mechanics or sliding mechanics is attractive because of its simplicity; the space site is closed by means of elastics or coil springs to provide force, and the brackets slide on the orthodontic archwire. On the other hand, frictionless mechanics uses loop bends to generate force to close the space site, allowing differential moments in the active and reactive units, leading to a less or more anchorage control, depending on the situation. Objective: This article will discuss various theoretical aspects and methods of space closure based on biomechanical concepts.
International Nuclear Information System (INIS)
1993-06-01
This document describes activities for the closure of a surface impoundment (2101-M Pond) at the Hanford Site. The 2101-H Pond was initially constructed in 1953 to serve as a drainage collection area for the 2101-H Building. (Until the Basalt Waste Isolation Project (BWIP) Laboratory was constructed in the 2101-M Building in 1979--1981, the only source contributing discharge to the pond was condensate water from the 2101-H Building heating, ventilation, and air conditioning (HVAC) system. The drains for the BWIP Laboratory rooms were plumbed into a 4-in., cast-iron, low-pressure drain pipe that carries waste water from the HVAC system to the pond. During the active life of the BWIP Laboratory, solutions of dissolved barium in groundwater samples were discharged to the 2101-M Pond via the laboratory drains. As a result of the discharges, a Part A permit application was initially submitted to the Washington State Department of Ecology (Ecology) in August 1986 which designates the 2101-M Pond as a surface impoundment
Independent particle Schroedinger Fluid: moments of inertia
International Nuclear Information System (INIS)
Kan, K.K.; Griffin, J.J.
1977-10-01
This philosophy of the Single Particle Schroedinger Fluid, especially as regards the velocity fields which find such a natural role therein, is applied to the study of the moments of inertia of independent Fermion system. It is shown that three simplified systems exhibit the rigid-body rotational velocity field in the limit of large A, and that the leading deviations, both on the average and fluctuating, from this large A limit can be described analytically, and verified numerically. For a single particle in a Hill-Wheeler box the moments are studied numerically, and their large fluctuations identified with the specific energy level degeneracies of its parallelepiped shape. The full assemblage of these new and old results is addressed to the question of the necessary and sufficient condition that the moment have the rigid value. Counterexamples are utilized to reject some conditions, and the conjecture is argued that Unconstrained Shape Equilibrium might be the necessary and sufficient condition. The spheroidal square well problem is identified as a promising test case
On the baryon magnetic moments
International Nuclear Information System (INIS)
Ferreira, P.L.
1976-01-01
In the context of quark confinement ideas, the baryon magnetic moments are calculated by assuming a SU(3) breaking due to the inequalities of the quark masses (m sub(p) different m sub(n) different m lambda ). The modified SU(6) result for the ratio of the magnetic moments of the neutron and proton is obtained. The p-quark is found heavier than the n-quark by circa 15 MeV. and alternative way of evaluating the baryon magnetic moments by means of simple physical considerations based on the properties of the SU(6) baryon S-waves functions is given
Moment Magnitude discussion in Austria
Weginger, Stefan; Jia, Yan; Hausmann, Helmut; Lenhardt, Wolfgang
2017-04-01
We implemented and tested the Moment Magnitude estimation „dbmw" from the University of Trieste in our Antelope near real-time System. It is used to get a fast Moment Magnitude solutions and Ground Motion Parameter (PGA, PGV, PSA 0.3, PSA 1.0 and PSA 3.0) to calculate Shake and Interactive maps. A Moment Magnitude Catalogue was generated and compared with the Austrian Earthquake Catalogue and all available Magnitude solution of the neighbouring agencies. Relations of Mw to Ml and Ground Motion to Intensity are presented.
International Nuclear Information System (INIS)
Matsuta, K.; Arimura, K.; Nagatomo, T.; Akutsu, K.; Iwakoshi, T.; Kudo, S.; Ogura, M.; Takechi, M.; Tanaka, K.; Sumikama, T.; Minamisono, K.; Miyake, T.; Minamisono, T.; Fukuda, M.; Mihara, M.; Kitagawa, A.; Sasaki, M.; Kanazawa, M.; Torikoshi, M.; Suda, M.; Hirai, M.; Momota, S.; Nojiri, Y.; Sakamoto, A.; Saihara, M.; Ohtsubo, T.; Alonso, J.R.; Krebs, G.F.; Symons, T.J.M.
2004-01-01
The magnetic moment of 33 Cl (Iπ=3/2+, T1/2=2.51s) has been re-measured precisely by β-NMR method. The obtained magnetic moment |μ|=0.7549(3)μN is consistent with the old value 0.7523(16)μN, but is 5 times more accurate. The value is well reproduced by the shell model calculation, μSM=0.70μN. Combined with the magnetic moment of the mirror partner 33 S, the nuclear matrix elements , , , and were derived
Moment methods with effective nuclear Hamiltonians; calculations of radial moments
International Nuclear Information System (INIS)
Belehrad, R.H.
1981-02-01
A truncated orthogonal polynomial expansion is used to evaluate the expectation value of the radial moments of the one-body density of nuclei. The expansion contains the configuration moments, , , and 2 >, where R/sup (k)/ is the operator for the k-th power of the radial coordinate r, and H is the effective nuclear Hamiltonian which is the sum of the relative kinetic energy operator and the Bruckner G matrix. Configuration moments are calculated using trace reduction formulae where the proton and neutron orbitals are treated separately in order to find expectation values of good total isospin. The operator averages are taken over many-body shell model states in the harmonic oscillator basis where all particles are active and single-particle orbitals through six major shells are included. The radial moment expectation values are calculated for the nuclei 16 O, 40 Ca, and 58 Ni and find that is usually the largest term in the expansion giving a large model space dependence to the results. For each of the 3 nuclei, a model space is found which gives the desired rms radius and then we find that the other 5 lowest moments compare favorably with other theoretical predictions. Finally, we use a method of Gordon (5) to employ the lowest 6 radial moment expectation values in the calculation of elastic electron scattering from these nuclei. For low to moderate momentum transfer, the results compare favorably with the experimental data
Closure and Sealing Design Calculation
International Nuclear Information System (INIS)
T. Lahnalampi; J. Case
2005-01-01
The purpose of the ''Closure and Sealing Design Calculation'' is to illustrate closure and sealing methods for sealing shafts, ramps, and identify boreholes that require sealing in order to limit the potential of water infiltration. In addition, this calculation will provide a description of the magma that can reduce the consequences of an igneous event intersecting the repository. This calculation will also include a listing of the project requirements related to closure and sealing. The scope of this calculation is to: summarize applicable project requirements and codes relating to backfilling nonemplacement openings, removal of uncommitted materials from the subsurface, installation of drip shields, and erecting monuments; compile an inventory of boreholes that are found in the area of the subsurface repository; describe the magma bulkhead feature and location; and include figures for the proposed shaft and ramp seals. The objective of this calculation is to: categorize the boreholes for sealing by depth and proximity to the subsurface repository; develop drawing figures which show the location and geometry for the magma bulkhead; include the shaft seal figures and a proposed construction sequence; and include the ramp seal figure and a proposed construction sequence. The intent of this closure and sealing calculation is to support the License Application by providing a description of the closure and sealing methods for the Safety Analysis Report. The closure and sealing calculation will also provide input for Post Closure Activities by describing the location of the magma bulkhead. This calculation is limited to describing the final configuration of the sealing and backfill systems for the underground area. The methods and procedures used to place the backfill and remove uncommitted materials (such as concrete) from the repository and detailed design of the magma bulkhead will be the subject of separate analyses or calculations. Post-closure monitoring will not
International Nuclear Information System (INIS)
Banach, Zbigniew; Larecki, Wieslaw
2013-01-01
The spectral formulation of the nine-moment radiation hydrodynamics resulting from using the Boltzmann entropy maximization procedure is considered. The analysis is restricted to the one-dimensional flows of a gas of massless fermions. The objective of the paper is to demonstrate that, for such flows, the spectral nine-moment maximum entropy hydrodynamics of fermionic radiation is not a purely formal theory. We first determine the domains of admissible values of the spectral moments and of the Lagrange multipliers corresponding to them. We then prove the existence of a solution to the constrained entropy optimization problem. Due to the strict concavity of the entropy functional defined on the space of distribution functions, there exists a one-to-one correspondence between the Lagrange multipliers and the moments. The maximum entropy closure of moment equations results in the symmetric conservative system of first-order partial differential equations for the Lagrange multipliers. However, this system can be transformed into the equivalent system of conservation equations for the moments. These two systems are consistent with the additional conservation equation interpreted as the balance of entropy. Exploiting the above facts, we arrive at the differential relations satisfied by the entropy function and the additional function required to close the system of moment equations. We refer to this additional function as the moment closure function. In general, the moment closure and entropy–entropy flux functions cannot be explicitly calculated in terms of the moments determining the state of a gas. Therefore, we develop a perturbation method of calculating these functions. Some additional analytical (and also numerical) results are obtained, assuming that the maximum entropy distribution function tends to the Maxwell–Boltzmann limit. (paper)
Microbial hotspots and hot moments in soil
Kuzyakov, Yakov; Blagodatskaya, Evgenia
2015-04-01
Soils are the most heterogeneous parts of the biosphere, with an extremely high differentiation of properties and processes within nano- to macroscales. The spatial and temporal heterogeneity of input of labile organics by plants creates microbial hotspots over short periods of time - the hot moments. We define microbial hotspots as small soil volumes with much faster process rates and much more intensive interactions compared to the average soil conditions. Such hotspots are found in the rhizosphere, detritusphere, biopores (including drilosphere) and on aggregate surfaces, but hotspots are frequently of mixed origin. Hot moments are short-term events or sequences of events inducing accelerated process rates as compared to the averaged rates. Thus, hotspots and hot moments are defined by dynamic characteristics, i.e. by process rates. For this hotspot concept we extensively reviewed and examined the localization and size of hotspots, spatial distribution and visualization approaches, transport of labile C to and from hotspots, lifetime and process intensities, with a special focus on process rates and microbial activities. The fraction of active microorganisms in hotspots is 2-20 times higher than in the bulk soil, and their specific activities (i.e. respiration, microbial growth, mineralization potential, enzyme activities, RNA/DNA ratio) may also be much higher. The duration of hot moments in the rhizosphere is limited and is controlled by the length of the input of labile organics. It can last a few hours up to a few days. In the detritusphere, however, the duration of hot moments is regulated by the output - by decomposition rates of litter - and lasts for weeks and months. Hot moments induce succession in microbial communities and intense intra- and interspecific competition affecting C use efficiency, microbial growth and turnover. The faster turnover and lower C use efficiency in hotspots counterbalances the high C inputs, leading to the absence of strong
Fast computation of Krawtchouk moments
Czech Academy of Sciences Publication Activity Database
Honarvar Shakibaei Asli, B.; Flusser, Jan
2014-01-01
Roč. 288, č. 1 (2014), s. 73-86 ISSN 0020-0255 R&D Projects: GA ČR GAP103/11/1552 Institutional support: RVO:67985556 Keywords : Krawtchouk polynomial * Krawtchouk moment * Geometric moment * Impulse response * Fast computation * Digital filter Subject RIV: JD - Computer Applications, Robotics Impact factor: 4.038, year: 2014 http://library.utia.cas.cz/separaty/2014/ZOI/flusser-0432452.pdf
Stochastic development regression using method of moments
DEFF Research Database (Denmark)
Kühnel, Line; Sommer, Stefan Horst
2017-01-01
This paper considers the estimation problem arising when inferring parameters in the stochastic development regression model for manifold valued non-linear data. Stochastic development regression captures the relation between manifold-valued response and Euclidean covariate variables using...... the stochastic development construction. It is thereby able to incorporate several covariate variables and random effects. The model is intrinsically defined using the connection of the manifold, and the use of stochastic development avoids linearizing the geometry. We propose to infer parameters using...... the Method of Moments procedure that matches known constraints on moments of the observations conditional on the latent variables. The performance of the model is investigated in a simulation example using data on finite dimensional landmark manifolds....
The cranking moment of inertia in a static potential
International Nuclear Information System (INIS)
Bengtsson, R.; Hamamoto, I.; Ibarra, R.H.
1978-01-01
Taking into account the self-consistency condition for the deformation, the authors estimate the cranking moment of inertia in the absence of pair-correlations for the Woods-Saxon potential and various versions of the modified oscillator potential. The authors investigate the expectation that in a static potential the moment of inertia is almost equal to the rigid-body moment of inertia at the self-consistent deformation. They examine especially the consequence of the presence of the l 2 term in the conventional modified oscillator potential. (Auth.)
Electric moments in molecule interferometry
International Nuclear Information System (INIS)
Eibenberger, Sandra; Gerlich, Stefan; Arndt, Markus; Tuexen, Jens; Mayor, Marcel
2011-01-01
We investigate the influence of different electric moments on the shift and dephasing of molecules in a matter wave interferometer. Firstly, we provide a quantitative comparison of two molecules that are non-polar yet polarizable in their thermal ground state and that differ in their stiffness and response to thermal excitations. While C 25 H 20 is rather rigid, its larger derivative C 49 H 16 F 52 is additionally equipped with floppy side chains and vibrationally activated dipole moment variations. Secondly, we elucidate the role of a permanent electric dipole momentby contrasting the quantum interference pattern of a (nearly) non-polar and a polar porphyrin derivative. We find that a high molecular polarizability and even sizeable dipole moment fluctuations are still well compatible with high-contrast quantum interference fringes. The presence of permanent electric dipole moments, however, can lead to a dephasing and rapid degradation of the quantum fringe pattern already at moderate electric fields. This finding is of high relevance for coherence experiments with large organic molecules, which are generally equipped with strong electric moments.
A TWO-MOMENT RADIATION HYDRODYNAMICS MODULE IN ATHENA USING A TIME-EXPLICIT GODUNOV METHOD
Energy Technology Data Exchange (ETDEWEB)
Skinner, M. Aaron; Ostriker, Eve C., E-mail: askinner@astro.umd.edu, E-mail: eco@astro.princeton.edu [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States)
2013-06-01
We describe a module for the Athena code that solves the gray equations of radiation hydrodynamics (RHD), based on the first two moments of the radiative transfer equation. We use a combination of explicit Godunov methods to advance the gas and radiation variables including the non-stiff source terms, and a local implicit method to integrate the stiff source terms. We adopt the M{sub 1} closure relation and include all leading source terms to O({beta}{tau}). We employ the reduced speed of light approximation (RSLA) with subcycling of the radiation variables in order to reduce computational costs. Our code is dimensionally unsplit in one, two, and three space dimensions and is parallelized using MPI. The streaming and diffusion limits are well described by the M{sub 1} closure model, and our implementation shows excellent behavior for a problem with a concentrated radiation source containing both regimes simultaneously. Our operator-split method is ideally suited for problems with a slowly varying radiation field and dynamical gas flows, in which the effect of the RSLA is minimal. We present an analysis of the dispersion relation of RHD linear waves highlighting the conditions of applicability for the RSLA. To demonstrate the accuracy of our method, we utilize a suite of radiation and RHD tests covering a broad range of regimes, including RHD waves, shocks, and equilibria, which show second-order convergence in most cases. As an application, we investigate radiation-driven ejection of a dusty, optically thick shell in the ISM. Finally, we compare the timing of our method with other well-known iterative schemes for the RHD equations. Our code implementation, Hyperion, is suitable for a wide variety of astrophysical applications and will be made freely available on the Web.
Fuel channel closure and adapter
International Nuclear Information System (INIS)
Cashen, W.S.
1985-01-01
This invention provides a mechanical closure/actuating ram combination particularly suited for use in sealing the ends of the pressure tubes when a CANDU-type reactor is refueled. It provides a cluster that may be inserted into a fuel channel end fitting to provide at least partial closing off of a pressure tube while permitting the disengagement of the fueling machine and its withdrawal from the closure for other purposes. The invention also provides a ram/closure combination wherein the application of loading force to a deformable sealing disk is regulated by a massive load bar component forming part of the fueling machine and being therefore accessible for maintenance or replacement
Static spacetimes with prescribed multipole moments: a proof of a conjecture by Geroch
International Nuclear Information System (INIS)
Herberthson, Magnus
2009-01-01
In this paper we give sufficient conditions on a sequence of multipole moments for a static spacetime to exist with precisely these moments. The proof is constructive in the sense that a metric having prescribed multipole moments up to a given order can be calculated. Since these sufficient conditions agree with already known necessary conditions, this completes the proof of a long standing conjecture due to Geroch.
Moments of inertia of neutron stars
Energy Technology Data Exchange (ETDEWEB)
Greif, Svenja Kim; Hebeler, Kai; Schwenk, Achim [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany); ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum fuer Schwerionenforschung GmbH (Germany)
2016-07-01
Neutron stars are unique laboratories for matter at extreme conditions. While nuclear forces provide systematic constraints on properties of neutron-rich matter up to around nuclear saturation density, the composition of matter at high densities is still unknown. Recent precise observations of 2 M {sub CircleDot} neutron stars made it possible to derive systematic constraints on the equation of state at high densities and also neutron star radii. Further improvements of these constraints require the observation of even heavier neutron stars or a simultaneous measurement of mass and radius of a single neutron star. Since the precise measurement of neutron star radii is an inherently difficult problem, the observation of moment of inertia of neutron stars provides a promising alternative, since they can be measured by pulsar timing experiments. We present a theoretical framework that allows to calculate moments of inertia microscopically, we show results based on state of the art equations of state and illustrate how future measurements of moments of inertia allow to constrain the equation of state and other properties of neutron stars.
Travel costs associated with flood closures of state highways near Centralia/Chehalis, Washington.
2014-09-01
This report discusses the travel costs associated with the closure of roads in the greater : Centralia/Chehalis, Washington region due to 100-year flood conditions starting on the Chehalis River. The costs : were computed for roadway closures on I-5,...
Vacuum with mesh is a feasible temporary closure device after fascial dehiscence
DEFF Research Database (Denmark)
Bjørsum-Meyer, Thomas; Skarbye, Mona; Jensen, Kenneth Højsgaard
2013-01-01
INTRODUCTION: The open abdomen is a challenging condition and a temporary abdominal closure device is required in order to protect the intra-abdominal viscera. We aimed to evaluate the feasibility of a recent device: vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM) after f...
40 CFR 265.280 - Closure and post-closure.
2010-07-01
... contaminants caused by wind erosion; and (4) Compliance with § 265.276 concerning the growth of food-chain... and post-closure care objectives of paragraph (a) of this section: (1) Type and amount of hazardous..., including amount, frequency, and pH of precipitation; (5) Geological and soil profiles and surface and...
Method of moments in electromagnetics
Gibson, Walton C
2007-01-01
Responding to the need for a clear, up-to-date introduction to the field, The Method of Moments in Electromagnetics explores surface integral equations in electromagnetics and presents their numerical solution using the method of moments (MOM) technique. It provides the numerical implementation aspects at a nuts-and-bolts level while discussing integral equations and electromagnetic theory at a higher level. The author covers a range of topics in this area, from the initial underpinnings of the MOM to its current applications. He first reviews the frequency-domain electromagnetic theory and t
Neutron star moments of inertia
Ravenhall, D. G.; Pethick, C. J.
1994-01-01
An approximation for the moment of inertia of a neutron star in terms of only its mass and radius is presented, and insight into it is obtained by examining the behavior of the relativistic structural equations. The approximation is accurate to approximately 10% for a variety of nuclear equations of state, for all except very low mass stars. It is combined with information about the neutron-star crust to obtain a simple expression (again in terms only of mass and radius) for the fractional moment of inertia of the crust.
Towards a collisionless fluid closure in plasma turbulence
Energy Technology Data Exchange (ETDEWEB)
Dif Pradalier, G
2005-07-01
In this work 2 generic possible descriptions of a plasma have been compared namely the kinetic and the fluid approaches. The latter focuses on the successive moments (n, u, p, q,...) of the distribution function, whereas the former describes the time-evolution in phase space of this distribution function, both being based on the Vlasov equation. The fluid description is attractive for the Vlasov equation is tractable with great difficulties. Nevertheless it rests on a major difficulty: as the set of fluid equations constitute an infinite hierarchy, a closure equation must be chosen. The first chapter details physical characteristics of a fundamental kinetic interaction mechanism between waves and particles. In chapter 2 we propose a fluid closure that allows analytic comparison with a linear fully kinetic result, near an homogeneous, electrostatic, Maxwellian equilibrium. This approach consists in adjusting chosen parameters in order to minimize the discrepancies between fluid and kinetic linear response functions. In chapter 3 we present a general frame for a fluid closure in a magnetized plasma. This is attempted in a linear, simplified model with low dimensionality.
Directory of Open Access Journals (Sweden)
Qian Huang
2016-01-01
Full Text Available Open abdomen (OA has been an effective treatment for abdominal catastrophes in traumatic and general surgery. However, management of patients with OA remains a formidable task for surgeons. The central goal of OA is closure of fascial defect as early as is clinically feasible without precipitating abdominal compartment syndrome. Historically, techniques such as packing, mesh, and vacuum-assisted closure have been developed to assist temporary abdominal closure, and techniques such as components separation, mesh-mediated traction, bridging fascial defect with permanent synthetic mesh, or biologic mesh have also been attempted to achieve early primary fascial closure, either alone or in combined use. The objective of this review is to present the challenges of these techniques for OA with a goal of early primary fascial closure, when the patient’s physiological condition allows.
2010-10-01
... Bluefish Fishery § 648.161 Closures. (a) EEZ closure. NMFS shall close the EEZ to fishing for bluefish by... dealer permit holders that no commercial quota is available for landing bluefish in that state. ...
CIRSE Vascular Closure Device Registry
International Nuclear Information System (INIS)
Reekers, Jim A.; Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria
2011-01-01
Purpose: Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. Methods: The CIRSE registry of closure devices with an anchor and a plug started in January 2009 and ended in August 2009. A total of 1,107 patients were included in the registry. Results: Deployment success was 97.2%. Deployment failure specified to access type was 8.8% [95% confidence interval (95% CI) 5.0–14.5] for antegrade access and 1.8% (95% CI 1.1–2.9) for retrograde access (P = 0.001). There was no difference in deployment failure related to local PVD at the access site. Calcification was a reason for deployment failure in only 5.9 cm, and two vessel occlusions. Conclusion: The conclusion of this registry of closure devices with an anchor and a plug is that the use of this device in interventional radiology procedures is safe, with a low incidence of serious access site complications. There seems to be no difference in complications between antegrade and retrograde access and other parameters.
304 Concretion facility closure plan
International Nuclear Information System (INIS)
1990-04-01
The Hanford Site, located northwest of Richland, Washington, houses reactors, chemical-separation systems, and related facilities used for the production of special nuclear materials. The 300 Area of the Hanford Site contains reactor fuel manufacturing facilities and several research and development laboratories. Recyclable scrap uranium Zircaloy-2 and copper silicon alloy, uranium-titanium alloy, beryllium/Zircaloy-2 alloy, and Zircaloy-2 chips and fines were secured in concrete billets in the 304 Concretion Facility, located in the 300 Area. The beryllium/Zircaloy-2 alloy and Zircaloy-2 chips and fines are designated as low-level radioactive mixed waste (LLRMW) with the characteristic of ignitability. The concretion process reduced the ignitability of the fines and chips for safe storage and shipment. This process has been discontinued and the 304 Concretion Facility is now undergoing closure as defined in the Resource Conservation and Recovery Act of 1976 (RCRA). This closure plan presents a description of the facility, the history of materials and wastes managed, and the procedures that will be followed to close the 304 Concretion Facility (304 Facility). Clean closure of the 304 Facility is the proposed method for closure of the facility. Justification for this proposal is presented. 15 refs., 22 figs., 4 tabs
Telephone switchboard closure | 19 December
2014-01-01
Exceptionally, the telephone switchboard will close at 4 p.m. on Friday, 19 December, instead of the usual time of 6 p.m., to allow time for closing all systems properly before the annual closure. Therefore, switchboard operator assistance to transfer calls from/to external lines will stop. All other phone services will run as usual.
CIRSE Vascular Closure Device Registry
Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria
2010-01-01
Purpose Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. Methods The CIRSE registry of closure devices with an anchor and a plug started in January 2009 and ended in August 2009. A total of 1,107 patients were included in the registry. Results Deployment success was 97.2%. Deployment failure specified to access type was 8.8% [95% confidence interval (95% CI) 5.0–14.5] for antegrade access and 1.8% (95% CI 1.1–2.9) for retrograde access (P = 0.001). There was no difference in deployment failure related to local PVD at the access site. Calcification was a reason for deployment failure in only 5.9 cm, and two vessel occlusions. Conclusion The conclusion of this registry of closure devices with an anchor and a plug is that the use of this device in interventional radiology procedures is safe, with a low incidence of serious access site complications. There seems to be no difference in complications between antegrade and retrograde access and other parameters. PMID:20981425
Quiet Moment around the Campfire
Centers for Disease Control (CDC) Podcasts
2014-06-18
Byron Breedlove reads his essay, "Quiet Moment around the Campfire," about the art of Frederic Remington and the transmission of pathogens as frontiers expand. Created: 6/18/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 6/19/2014.
Particle electric dipole-moments
Energy Technology Data Exchange (ETDEWEB)
Pendlebury, J M [Sussex Univ., Brighton (United Kingdom)
1997-04-01
The incentive to detect particle electric dipole-moments, as a window on time-reversal violation, remains undiminished. Efforts to improve the measurements for the neutron, the electron and some nuclei are still making rapid progress as more powerful experimental methods are brought to bear. A new measurement for the neutron at ILL is presented. (author). 7 refs.
Moment of Inertia by Differentiation
Rizcallah, Joseph A.
2015-01-01
The calculation of the moment of inertia of an extended body, as presented in standard introductory-level textbooks, involves the evaluation of a definite integral--an operation often not fully mastered by beginners, let alone the conceptual difficulties it presents, even to the advanced student, in understanding and setting up the integral in the…
Unteachable Moments and Pedagogical Relationships
Wang, Hongyu
2016-01-01
This paper discusses how Julia Kristeva's theory can inform our understanding of unteachable moments. It proposes a pedagogical relationship that can contain breakdowns of meanings and work toward breakthroughs to new awareness, particularly related to social justice pedagogy in teacher education. First, one example from the author's own teaching…
Moment Distributions of Phase Type
DEFF Research Database (Denmark)
Bladt, Mogens; Nielsen, Bo Friis
2011-01-01
Moment distributions of phase-type and matrix-exponential distributions are shown to remain within their respective classes. We provide a probabilistic phase-type representation for the former case and an alternative representation, with an analytically appealing form, for the latter. First order...
Moment methods and Lanczos methods
International Nuclear Information System (INIS)
Whitehead, R.R.
1980-01-01
In contrast to many of the speakers at this conference I am less interested in average properties of nuclei than in detailed spectroscopy. I will try to show, however, that the two are very closely connected and that shell-model calculations may be used to give a great deal of information not normally associated with the shell-model. It has been demonstrated clearly to us that the level spacing fluctuations in nuclear spectra convey very little physical information. This is true when the fluctuations are averaged over the entire spectrum but not if one's interest is in the lowest few states, whose spacings are relatively large. If one wishes to calculate a ground state (say) accurately, that is with an error much smaller than the excitation energy of the first excited state, very high moments, μ/sub n/, n approx. 200, are needed. As I shall show, we use such moments as a matter of course, albeit without actually calculating them; in fact I will try to show that, if at all possible, the actual calculations of moments is to be avoided like the plague. At the heart of the new shell-model methods embodied in the Glasgow shell-model program and one or two similar ones is the so-called Lanczos method and this, it turns out, has many deep and subtle connections with the mathematical theory of moments. It is these connections that I will explore here
Fetal endoscopic myelomeningocele closure preserves segmental neurological function
Verbeek, Renate J.; Heep, Axel; Maurits, Natalia M.; Cremer, Reinhold; Hoving, Eelco W.; Brouwer, Oebele F.; Van der Hoeven, Johannes H.; Sival, Deborah A.
AIM: Our aim was to compare the effect of prenatal endoscopic with postnatal myelomeningocele closure (fetally operated spina bifida aperta [fSBA]) versus neonatally operated spina bifida aperta [nSBA]) on segmental neurological leg condition. METHOD: Between 2003 and 2009, the fetal surgical
Responses of primary producers to mouth closure in the temporarily ...
African Journals Online (AJOL)
Low river inflow conditions during 2009/2010 resulted in the mouth of the Great Brak Estuary remaining closed for almost two years. The low water level in Wolwedans Dam resulted in no annual environmental flow releases being made, causing mouth closure. The response of primary producers to this prolonged period of ...
Moments and mean square charge radii of short-lived argon isotopes
Klein, A; Georg, U; Keim, M; Lievens, P; Neugart, R; Neuroth, M; Silverans, R E; Vermeeren, L
1996-01-01
We report on the measurement of optical isotope shifts for $^{32-40}$Ar and for $^{46}$Ar from which the changes in mean square nuclear charge radii across the N = 20 neutron shell closure are deducted. The investigations were carried out by collinear laser spectroscopy in fast beams of neutral argon atoms. The ultra-sensitive detection combines optical pumping, state-selective collisional ionization and counting of $\\beta$-radioactivity. By reaching far into the sd-shell, the results add new information to the systematics of radii in the calcium region (Z $\\approx$ 20). Contrary to all major neutron shell closures with N $\\geq$ 28, the N = 20 shell closure causes no significant slope change in the development of the radii. Information from the hyperfine structure of the odd-A isotopes includes includes the magnetic moments of $^{33}$Ar (I=1/2) and $^{39}$Ar (I=7/2), and the quadrupole moments of $^{35}$Ar, $^{37}$Ar (I=3/2) and $^{39}$Ar. The electromagnetic moments are compared to shell-model predictions fo...
Stochastic analysis of complex reaction networks using binomial moment equations.
Barzel, Baruch; Biham, Ofer
2012-09-01
The stochastic analysis of complex reaction networks is a difficult problem because the number of microscopic states in such systems increases exponentially with the number of reactive species. Direct integration of the master equation is thus infeasible and is most often replaced by Monte Carlo simulations. While Monte Carlo simulations are a highly effective tool, equation-based formulations are more amenable to analytical treatment and may provide deeper insight into the dynamics of the network. Here, we present a highly efficient equation-based method for the analysis of stochastic reaction networks. The method is based on the recently introduced binomial moment equations [Barzel and Biham, Phys. Rev. Lett. 106, 150602 (2011)]. The binomial moments are linear combinations of the ordinary moments of the probability distribution function of the population sizes of the interacting species. They capture the essential combinatorics of the reaction processes reflecting their stoichiometric structure. This leads to a simple and transparent form of the equations, and allows a highly efficient and surprisingly simple truncation scheme. Unlike ordinary moment equations, in which the inclusion of high order moments is prohibitively complicated, the binomial moment equations can be easily constructed up to any desired order. The result is a set of equations that enables the stochastic analysis of complex reaction networks under a broad range of conditions. The number of equations is dramatically reduced from the exponential proliferation of the master equation to a polynomial (and often quadratic) dependence on the number of reactive species in the binomial moment equations. The aim of this paper is twofold: to present a complete derivation of the binomial moment equations; to demonstrate the applicability of the moment equations for a representative set of example networks, in which stochastic effects play an important role.
75 FR 29322 - Base Closure and Realignment
2010-05-25
... DEPARTMENT OF DEFENSE Office of the Secretary Base Closure and Realignment AGENCY: Office of...)(ii) of the Defense Base Closure and Realignment Act of 1990. It provides a partial list of military installations closing or realigning pursuant to the 2005 Base Closure and Realignment (BRAC) Report. It also...
Regularized κ-distributions with non-diverging moments
Scherer, K.; Fichtner, H.; Lazar, M.
2017-12-01
For various plasma applications the so-called (non-relativistic) κ-distribution is widely used to reproduce and interpret the suprathermal particle populations exhibiting a power-law distribution in velocity or energy. Despite its reputation the standard κ-distribution as a concept is still disputable, mainly due to the velocity moments M l which make a macroscopic characterization possible, but whose existence is restricted only to low orders l definition of the κ-distribution itself is conditioned by the existence of the moment of order l = 2 (i.e., kinetic temperature) satisfied only for κ > 3/2 . In order to resolve these critical limitations we introduce the regularized κ-distribution with non-diverging moments. For the evaluation of all velocity moments a general analytical expression is provided enabling a significant step towards a macroscopic (fluid-like) description of space plasmas, and, in general, any system of κ-distributed particles.
Maximal Electric Dipole Moments of Nuclei with Enhanced Schiff Moments
Ellis, John; Pilaftsis, Apostolos
2011-01-01
The electric dipole moments (EDMs) of heavy nuclei, such as 199Hg, 225Ra and 211Rn, can be enhanced by the Schiff moments induced by the presence of nearby parity-doublet states. Working within the framework of the maximally CP-violating and minimally flavour-violating (MCPMFV) version of the MSSM, we discuss the maximal values that such EDMs might attain, given the existing experimental constraints on the Thallium, neutron and Mercury EDMs. The maximal EDM values of the heavy nuclei are obtained with the help of a differential-geometrical approach proposed recently that enables the maxima of new CP-violating observables to be calculated exactly in the linear approximation. In the case of 225Ra, we find that its EDM may be as large as 6 to 50 x 10^{-27} e.cm.
Moment stability for a predator–prey model with parametric dichotomous noises
International Nuclear Information System (INIS)
Jin Yan-Fei
2015-01-01
In this paper, we investigate the solution moment stability for a Harrison-type predator–prey model with parametric dichotomous noises. Using the Shapiro–Loginov formula, the equations for the first-order and second-order moments are obtained and the corresponding stable conditions are given. It is found that the solution moment stability depends on the noise intensity and correlation time of noise. The first-order and second-order moments become unstable with the decrease of correlation time. That is, the dichotomous noise can improve the solution moment stability with respect to Gaussian white noise. Finally, some numerical results are presented to verify the theoretical analyses. (paper)
DEFF Research Database (Denmark)
Dippmann, Christian; Kraemer, Otto; Lund, Bent
2018-01-01
in patients without additional risk factors for instability such as hypermobility or dysplasia of the hip. We hypothesised that capsular closure will lead to a superior outcome in hip arthroscopy for femoroacetabular impingement syndrome (FAIS) compared with non-capsular closure. METHODS AND ANALYSIS...... years and FAIS according to the Warwick agreement. Exclusion criteria are: previous hip surgery in either hip, previous conditions of Legg-Calvé-Perthes or slipped capital femoral epiphysis, malignant disease, recent hip or pelvic fractures, arthritis, Ehlers-Danlos or Marfan disease, recent (within 6...
A mapping closure for turbulent scalar mixing using a time-evolving reference field
Girimaji, Sharath S.
1992-01-01
A general mapping-closure approach for modeling scalar mixing in homogeneous turbulence is developed. This approach is different from the previous methods in that the reference field also evolves according to the same equations as the physical scalar field. The use of a time-evolving Gaussian reference field results in a model that is similar to the mapping closure model of Pope (1991), which is based on the methodology of Chen et al. (1989). Both models yield identical relationships between the scalar variance and higher-order moments, which are in good agreement with heat conduction simulation data and can be consistent with any type of epsilon(phi) evolution. The present methodology can be extended to any reference field whose behavior is known. The possibility of a beta-pdf reference field is explored. The shortcomings of the mapping closure methods are discussed, and the limit at which the mapping becomes invalid is identified.
Closure plan for the proposed Millennium Project
International Nuclear Information System (INIS)
Tuttle, S.; Sisson, R.
1999-01-01
A $2.2 billion expansion of the current oil sands operation has been proposed by Suncor Energy Inc. The expansion would more than double the productive capacity of the present facility. As part of the application for this expansion, called Project Millennium, a comprehensive closure plan has been developed and filed by the Corporation. The Plan includes a systematic evaluation of the area to be developed, a description of the development activities planned, and the goals and objectives of the Corporation in re-establishing the landforms and ecosystems concurrently with running the operation. The Plan envisages surface contouring as early as practicable during the mine development, soil reconstruction, and re-establishment of vegetation, surface drainage and wetlands. The Corporation undertakes to monitor the performance of the reclaimed areas based on landform performance, the impact of chemical constituents on the landscape and ecosystem sustainability. An annual monitoring report assessing herbaceous vegetation growth, major species composition, tree and shrub survival and growth rate, groundwater conditions, amount of precipitation, the utility of constructed wetlands for treatment of reclamation area seepage and runoff waters, and wildlife population changes, will be prepared annually. A future research program associated with the Reclamation and Closure Plan will also examine the effectiveness of the reclamation drainage system as fish habitat, and the potential of the proposed end-pit lake to provide a viable aquatic ecosystem. 8 refs., 2 figs
The Critical Moment of Transition
DEFF Research Database (Denmark)
Svalgaard, Lotte
2018-01-01
By providing a holding environment to acknowledge sensitivities and address emotions, leadership programs prove to be powerful spaces for increasing self- and social awareness. However, the challenge is for one to maintain the newly gained self- and social awareness after leaving the holding...... environment and entering a context characterized by activity and performance. This is a frequently debated challenge for both academics and providers of management learning. Yet, critical moments in this transition remain under-exposed and under-researched. The contribution of this article is a research study......—within the context of an international MBA program—of MBA students applying their knowledge from a Leadership Stream in an international consultancy project. This article contributes to the theory and practice of management learning by providing a lens through which subjective experience of critical moments...
2006-01-01
One of the first events reconstructed in the Muon Drift Tubes, the Hadron Calorimeter and elements of the Silicon Tracker (TK) at 3 Tesla. The atmosphere in the CMS control rooms was electric. Everbody was at the helm for the first full-scale testing of the experiment. This was a crunch moment for the entire collaboration. On Tuesday, 22 August the magnet attained almost its nominal power of 4 Tesla! At the same moment, in a tiny improvised control room, the physicists were keyed up to test the entire detector system for the first time. The first cosmic ray tracks appeared on their screens in the week of 15 August. The tests are set to continue for several weeks more until the first CMS components are lowered into their final positions in the cavern.
Moment Distributions of Phase Type
DEFF Research Database (Denmark)
Bladt, Mogens; Nielsen, Bo Friis
In this paper we prove that the class of distributions on the positive reals with a rational Laplace transform, also known as matrix-exponential distributions, is closed under formation of moment distributions. In particular, the results are hence valid for the well known class of phase-type dist...... alternative representation in terms of sub{intensity matrices. Finally we are able to nd explicit expressions for both the Lorenz curve and the Gini index....
Electric Dipole Moments of Hadrons
Wirzba, Andreas
2016-01-01
A nonzero electric dipole moment (EDM) of the neutron, proton, deuteron, helion or any finite system necessarily involves the breaking of a symmetry, either by the presence of external fields (leading to the case of induced EDMs) or explicitly by the breaking of the discrete parity and time-reflection symmetries in the case of permanent EDMs. Recent - and in the case of the deuteron even unpublished - results for the relevant matrix elements of nuclear EDM operators are presented and the rel...
A moment-convergence method for stochastic analysis of biochemical reaction networks.
Zhang, Jiajun; Nie, Qing; Zhou, Tianshou
2016-05-21
Traditional moment-closure methods need to assume that high-order cumulants of a probability distribution approximate to zero. However, this strong assumption is not satisfied for many biochemical reaction networks. Here, we introduce convergent moments (defined in mathematics as the coefficients in the Taylor expansion of the probability-generating function at some point) to overcome this drawback of the moment-closure methods. As such, we develop a new analysis method for stochastic chemical kinetics. This method provides an accurate approximation for the master probability equation (MPE). In particular, the connection between low-order convergent moments and rate constants can be more easily derived in terms of explicit and analytical forms, allowing insights that would be difficult to obtain through direct simulation or manipulation of the MPE. In addition, it provides an accurate and efficient way to compute steady-state or transient probability distribution, avoiding the algorithmic difficulty associated with stiffness of the MPE due to large differences in sizes of rate constants. Applications of the method to several systems reveal nontrivial stochastic mechanisms of gene expression dynamics, e.g., intrinsic fluctuations can induce transient bimodality and amplify transient signals, and slow switching between promoter states can increase fluctuations in spatially heterogeneous signals. The overall approach has broad applications in modeling, analysis, and computation of complex biochemical networks with intrinsic noise.
A moment-convergence method for stochastic analysis of biochemical reaction networks
Energy Technology Data Exchange (ETDEWEB)
Zhang, Jiajun [School of Mathematics and Computational Science, Sun Yat-Sen University, Guangzhou 510275 (China); Nie, Qing [Department of Mathematics, University of California at Irvine, Irvine, California 92697 (United States); Zhou, Tianshou, E-mail: mcszhtsh@mail.sysu.edu.cn [School of Mathematics and Computational Science, Sun Yat-Sen University, Guangzhou 510275 (China); Guangdong Province Key Laboratory of Computational Science and School of Mathematics and Computational Science, Sun Yat-Sen University, Guangzhou 510275 (China)
2016-05-21
Traditional moment-closure methods need to assume that high-order cumulants of a probability distribution approximate to zero. However, this strong assumption is not satisfied for many biochemical reaction networks. Here, we introduce convergent moments (defined in mathematics as the coefficients in the Taylor expansion of the probability-generating function at some point) to overcome this drawback of the moment-closure methods. As such, we develop a new analysis method for stochastic chemical kinetics. This method provides an accurate approximation for the master probability equation (MPE). In particular, the connection between low-order convergent moments and rate constants can be more easily derived in terms of explicit and analytical forms, allowing insights that would be difficult to obtain through direct simulation or manipulation of the MPE. In addition, it provides an accurate and efficient way to compute steady-state or transient probability distribution, avoiding the algorithmic difficulty associated with stiffness of the MPE due to large differences in sizes of rate constants. Applications of the method to several systems reveal nontrivial stochastic mechanisms of gene expression dynamics, e.g., intrinsic fluctuations can induce transient bimodality and amplify transient signals, and slow switching between promoter states can increase fluctuations in spatially heterogeneous signals. The overall approach has broad applications in modeling, analysis, and computation of complex biochemical networks with intrinsic noise.
Observations on early and delayed colostomy closure.
Tade, A O; Salami, B A; Ayoade, B A
2011-06-01
Traditional treatment of a variety of colorectal pathologies had included a diverting colostomy that was closed eight or more weeks later during a readmission. The aim of this retrospective study was to determine the outcomes of early colostomy closure and delayed colostomy closure in patients with temporary colostomies following traumatic and non-traumatic colorectal pathologies. In this study early colostomy closure was the closure of a colostomy within three weeks of its construction, while delayed colostomy closure referred to closure after 3 weeks. Complete records of the 37 adult patients who had temporary colostomy constructed and closed between Jan. 1997 December 2003 for various colorectal pathologies were studied. Fourteen patients had early colostomy closure while 23 had delayed closure. In the early colostomy closure group there were 10 men and 4 women. The mean age of the patients was 28yr with a range of 18-65yr. Colostomies were closed 9-18 days after initial colostomy construction. There was no mortality. Morbidity rate 28.6% (4 out of 14). There were two faecal fistulas (14.3%). Twenty-three patients had delayed colostomy closure 8 weeks to 18 months after initial colostomy construction. These were patients unfit for early surgery after initial colostomy construction because of carcinoma, significant weight loss, or sepsis. There was no mortality. Morbidity rate was 26.1%. There were 3 faecal fistulas (13.2%). Outcomes following early colostomy closure and delayed closure were comparable. Patients fit for surgery should have early closure whilst patients who may have compromised health should have delayed closure.
304 Concretion Facility Closure Plan
International Nuclear Information System (INIS)
1991-10-01
The Hanford Site, located northwest of Richland, Washington, houses reactors, chemical-separation systems, and related facilities used for the production of special nuclear materials. The 300 Area of the Hanford Site contains reactor fuel manufacturing facilities and several research and development laboratories. Recyclable scrap uranium with Zircaloy-2 and copper silicon allo , uranium-titanium alloy, beryllium/Zircaloy-2 alloy, and Zircaloy-2 chips and fines were secured in concrete billets (7.5-gal containers) in the 304 Concretion Facility (304 Facility), located in the 300 Area. The beryllium/Zircaloy-2 alloy and Zircaloy-2 chips and fines are designated as low-level radioactive mixed waste (LLRMW) with the characteristic of ignitability. The concretion process reduced the ignitability of the fines and chips for safe storage and shipment. This process has been discontinued and the 304 Concretion Facility is now undergoing closure as defined in the Resource Conservation and Recovery Act of 1976 (RCRA) and the Washington Administrative Code (WAC) Dangerous Waste Regulations, WAC 173-303-040 (Ecology 1991). This closure plan presents a description of the facility, the history of materials and wastes managed, and the procedures that will be followed to close the 304 Facility. The strategy for closure of the 304 Facility is presented in Section 6.0
Self-assembly and flux closure studies of magnetic nanoparticle rings
DEFF Research Database (Denmark)
Wei, Alexander; Kasama, Takeshi; Dunin-Borkowski, Rafal E.
2011-01-01
Thermoremanent magnetic nanoparticles (MNPs) can self-assemble into rings through dipolar interactions, when dispersed under appropriate conditions. Analysis of individual MNP rings and clusters by off-axis electron holography reveals bistable flux closure (FC) states at ambient temperatures...
Adaptive wall treatment for a second moment closure in the industrial context
International Nuclear Information System (INIS)
Wald, Jean-Francois
2016-01-01
CFD computations of turbulent flows always begin with a complex meshing process (upper plenum, fuel assembly in the nuclear industry for example). Geometrical constraints are the first ones to be satisfied (level of details, important zones to refine regarding 'user experiences'). One has however to satisfy constraints that are inherent to the RANS model (Reynolds Averaged Navier Stokes) used for the computation. For example, if a 'High-Reynolds' (κ-ε standard, SSG,...) model is used one should only have wall cells with a dimensionless distance to the wall greater or equal to 20 to justify the use of the universal 'law of the wall'. On the other hand, if a 'Low-Reynolds' (BL-v"2/k, EB-RSM,...) model is used, one should only find wall cells with a dimensionless distance to the wall below 1. If those models are used in an inappropriate way the results could be dramatic (computations can either diverge or give unphysical results). This thesis proposes the development of a new turbulence model with adaptive wall treatments that gives satisfactory results on all types of meshes. In particular, the model will be able to cope with meshes containing both 'High-Reynolds' and 'Low-Reynolds' wall cells. Given the complex flows encountered in the nuclear industry this thesis will use a model known for its good behavior: the EB-RSM model. This model is able to reproduce the anisotropy of the turbulence and give more satisfactory results than eddy viscosity models in different configurations. This model is available in Code Saturne, an open source code developed at EDF. All the developments are made in this code. (author)
Roy, Subrata P.; Arias, Paul G.; Lecoustre, Vivien R.; Haworth, Daniel C.; Im, Hong G.; Trouvé , Arnaud C.
2014-01-01
of ad hoc treatments such as clipping. The solutions proposed and demonstrated here are being applied to generate new physical insight into complex turbulence-chemistry-soot-radiation interactions in turbulent reacting flows using DNS. © 2014 Copyright
Magnetic dipole moments of 58Cu and 59Cu by in-source laser spectroscopy
International Nuclear Information System (INIS)
Stone, N. J.; Koester, U.; Stone, J. Rikovska; Fedorov, D. V.; Fedoseyev, V. N.; Flanagan, K. T.; Hass, M.; Lakshmi, S.
2008-01-01
Online measurements of the magnetic dipole moments and isotope shifts of 58 Cu and 59 Cu by the in-source laser spectroscopy method are reported. The results for the magnetic moments are μ ( 58 Cu) =+0.52(8) μ N ,μ( 59 Cu) =+1.84(3) μ N and for the isotope shifts δν 59,65 =1.72(22) GHz and δν 58,65 =1.99(30) GHz in the transition from the 3d 10 4s 2 S 1/2 ground state to the 3d 10 4p 2 P 1/2 state in Cu I. The magnetic moment of 58 Cu is discussed in the context of the strength of the subshell closure at 56 Ni, additivity rules and large-scale shell model calculations
CSIR Research Space (South Africa)
Malan, DF
2003-03-01
Full Text Available with strain bursting conditions, while low values (< 0.1) are associated with significant risks of falls of ground. The typical closure ratio calculated for the experimental site at Mponeng Mine was 0.5. Fortunately no face bursting occurred during... the period of monitoring but any possible changes in closure ratio preceding bursts could therefore not be investigated. Another preliminary finding is that it appears that the closure ratio is relatively independent of position along the stope face...
Directory of Open Access Journals (Sweden)
A. Reichert
2016-09-01
Full Text Available We present a first quantification of the near-infrared (NIR water vapor continuum absorption from an atmospheric radiative closure experiment carried out at the Zugspitze (47.42° N, 10.98° E; 2964 m a.s.l.. Continuum quantification is achieved via radiative closure using radiometrically calibrated solar Fourier transform infrared (FTIR absorption spectra covering the 2500 to 7800 cm−1 spectral range. The dry atmospheric conditions at the Zugspitze site (IWV 1.4 to 3.3 mm enable continuum quantification even within water vapor absorption bands, while upper limits for continuum absorption can be provided in the centers of window regions. Throughout 75 % of the 2500 to 7800 cm−1 spectral range, the Zugspitze results agree within our estimated uncertainty with the widely used MT_CKD 2.5.2 model (Mlawer et al., 2012. In the wings of water vapor absorption bands, our measurements indicate about 2–5 times stronger continuum absorption than MT_CKD, namely in the 2800 to 3000 cm−1 and 4100 to 4200 cm−1 spectral ranges. The measurements are consistent with the laboratory measurements of Mondelain et al. (2015, which rely on cavity ring-down spectroscopy (CDRS, and the calorimetric–interferometric measurements of Bicknell et al. (2006. Compared to the recent FTIR laboratory studies of Ptashnik et al. (2012, 2013, our measurements are consistent within the estimated errors throughout most of the spectral range. However, in the wings of water vapor absorption bands our measurements indicate typically 2–3 times weaker continuum absorption under atmospheric conditions, namely in the 3200 to 3400, 4050 to 4200, and 6950 to 7050 cm−1 spectral regions.
On the interpretation of the support moment
Hof, AL
2000-01-01
It has been suggested by Winter (J. Biomech. 13 (1980) 923-927) that the 'support moment', the sum of the sagittal extension moments, shows less variability in walking than any of the joint moments separately. A simple model is put forward to explain this finding. It is proposed to reformulate the
Gonioscopy in primary angle closure glaucoma.
Bruno, Christina A; Alward, Wallace L M
2002-06-01
Primary angle closure is a condition characterized by obstruction to aqueous humor outflow by the peripheral iris, and results in changes in the iridocorneal angle that are visible through gonioscopic examination. Gonioscopy in these eyes, however, can be difficult. This chapter discusses techniques that might help in the examination. These include beginning the examination with the inferior angle, methods to help in looking over the iris, cycloplegia, locating the corneal wedge, indentation, van Herick estimation, examining the other eye, and topical glycerin. Finally, there is a discussion about the pathology associated with the closed angle, with emphasis on the appearance of iris bombé, plateau iris, and the distinction between iris processes and peripheral anterior synechiae.
Electric and Magnetic Dipole Moments
CERN. Geneva
2005-01-01
The stringent limit on the electric dipole moment of the neutron forced the issue on the strong CP-problem. The most elegant solution of which is the axion field proposed by Peccei and Quinn. The current limit on the QCD parameter theta coming from the limit on the neutron EDM is of order 10-10. I am going to describe the present status on the neutron EDM searches and further prospects on getting down to theta_qcd sensitivity of 10-13 with the new deuteron EDM in storage rings proposal. For completeness the current status and prospects of the muon g-2 experiment will also be given.
The Muon Electric Dipole Moment
Barger, Vernon; Kao, Chung; Das, Ashok
1997-01-01
The electric dipole moment of the muon ($d_\\mu$) is evaluated in a two Higgs doublet model with a softly broken discrete symmetry. For $\\tan\\beta \\equiv |v_2|/|v_1| \\sim 1$, contributions from two loop diagrams involving the $t$ quark and the $W$ boson dominate; while for $\\tan\\beta \\gsim 10$, contributions from two loop diagrams involving the $b$ quark and the $\\tau$ lepton are dominant. For $8 \\gsim \\tan\\beta \\gsim 4$, significant cancellation occurs among the contributions from two loop di...
Storage shaft definitive closure plug and method
International Nuclear Information System (INIS)
Dardaine, M.
1992-01-01
A definitive closure plug system for radioactive waste storage at any deepness, is presented. The inherent weight of the closure materials is used to set in the plug: these materials display an inclined sliding surface in such a way that when the closure material rests on a stable surface of the shaft storage materials, the relative sliding of the different materials tends to spread them towards the shaft internal wall so as to completely occlude the shaft
Requirements for moment connections in statically indeterminate timber structures
Leijten, A.J.M.
2011-01-01
In statically indeterminate structures, connections play a vital role in the moment distribution. Demonstrated here is a method to evaluate the conditions, taking full advantage of the benefits offered by the indeterminate nature of the structures, and using the well-established, graphical beam-line
100-D Ponds closure plan. Revision 1
International Nuclear Information System (INIS)
Petersen, S.W.
1997-09-01
The 100-D Ponds is a Treatment, Storage, and Disposal (TSD) unit on the Hanford Facility that received both dangerous and nonregulated waste. This Closure Plan (Rev. 1) for the 100-D Ponds TSD unit consists of a RCRA Part A Dangerous Waste Permit Application (Rev. 3), a RCRA Closure Plan, and supporting information contained in the appendices to the plan. The closure plan consists of eight chapters containing facility description, process information, waste characteristics, and groundwater monitoring data. There are also chapters containing the closure strategy and performance standards. The strategy for the closure of the 100-D Ponds TSD unit is clean closure. Appendices A and B of the closure plan demonstrate that soil and groundwater beneath 100-D Ponds are below cleanup limits. All dangerous wastes or dangerous waste constituents or residues associated with the operation of the ponds have been removed, therefore, human health and the environment are protected. Discharges to the 100-D Ponds, which are located in the 100-DR-1 operable unit, were discontinued in June 1994. Contaminated sediment was removed from the ponds in August 1996. Subsequent sampling and analysis demonstrated that there is no contamination remaining in the ponds, therefore, this closure plan is a demonstration of clean closure
Closure Welding of Plutonium Bearing Storage Containers
International Nuclear Information System (INIS)
Cannell, G.R.
2002-01-01
A key element in the Department of Energy (DOE) strategy for the stabilization, packaging and storage of plutonium-bearing materials involves closure welding of DOE-STD-3013 Outer Containers (3013 container). The 3013 container provides the primary barrier and pressure boundary preventing release of plutonium-bearing materials to the environment. The final closure (closure weld) of the 3013 container must be leaktight, structurally sound and meet DOE STD 3013 specified criteria. This paper focuses on the development, qualification and demonstration of the welding process for the closure welding of Hanford PFP 3013 outer containers
Moment-to-moment dynamics of ADHD behaviour
Directory of Open Access Journals (Sweden)
Aase Heidi
2005-08-01
learning long behavioural sequences may ultimately lead to deficient development of verbally governed behaviour and self control. The study represents a new approach to analyzing the moment-to-moment dynamics of behaviour, and provides support for the theory that reinforcement processes are altered in ADHD.
Review on improved seismic imaging with closure phase
Schuster, Gerard T.
2014-08-13
The timing and amplitudes of arrivals recorded in seismic traces are influenced by velocity variations all along the associated raypaths. Consequently, velocity errors far from the target can lead to blurred imaging of the target body. To partly remedy this problem, we comprehensively reviewed inverting differential traveltimes that satisfied the closure-phase condition. The result is that the source and receiver statics are completely eliminated in the data and velocities far from the target do not need to be known. We successfully used the phase closure equation for traveltime tomography, refraction statics, migration, refraction tomography, and earthquake location, all of which demonstrated the higher resolution achievable by processing data with differential traveltimes rather than absolute traveltimes. More generally, the stationary version of the closure-phase equation is equivalent to Fermat’s principle and can be derived from the equations of seismic interferometry. In summary, the general closure-phase equation is the mathematical foundation for approximately redatuming sources and/or receivers to the target of interest without the need to accurately know the statics or the velocity model away from the target.
Application of statistical dynamical turbulence closures to data assimilation
International Nuclear Information System (INIS)
O'Kane, Terence J; Frederiksen, Jorgen S
2010-01-01
We describe the development of an accurate yet computationally tractable statistical dynamical closure theory for general inhomogeneous turbulent flows, coined the quasi-diagonal direct interaction approximation closure (QDIA), and its application to problems in data assimilation. The QDIA provides prognostic equations for evolving mean fields, covariances and higher-order non-Gaussian terms, all of which are also required in the formulation of data assimilation schemes for nonlinear geophysical flows. The QDIA is a generalization of the class of direct interaction approximation theories, initially developed by Kraichnan (1959 J. Fluid Mech. 5 497) for isotropic turbulence, to fully inhomogeneous flows and has been further generalized to allow for both inhomogeneous and non-Gaussian initial conditions and long integrations. A regularization procedure or empirical vertex renormalization that ensures correct inertial range spectra is also described. The aim of this paper is to provide a coherent mathematical description of the QDIA turbulence closure and closure-based data assimilation scheme we have labeled the statistical dynamical Kalman filter. The mathematical formalism presented has been synthesized from recent works of the authors with some additional material and is presented in sufficient detail that the paper is of a pedagogical nature.
MCO closure welding process parameter development and qualification
International Nuclear Information System (INIS)
CANNELL, G.R.
2003-01-01
One of the key elements in the SNF process is final closure of the MCO by welding. Fuel is loaded into the MCO (approximately 2 ft. in diameter and 13 ft. long) and a heavy shield plug is inserted into the top, creating a mechanical seal. The plug contains several process ports for various operations, including vacuum drying and inert-gas backfilling of the packaged fuel. When fully processed, the Canister Cover Assembly (CCA) is placed over the shield plug and final closure made by welding. The following reports the effort between the Amer Industrial Technology (AIT) and Fluor Hanford (FH) to develop and qualify the welding process for making the final closure--with primary emphasis on developing a set of robust parameters for deposition of the root pass. Work was carried out in three phases: (1) Initial welding process and equipment selection with subsequent field demonstration testing; (2) Development and qualification of a specific process technique and parameters; and (3) Validation of the process and parameters at the CSB under mock production conditions. This work establishes the process technique and parameters that provide a high level of confidence that acceptable MCO closure welds will be made on a consistent and repeatable basis
Crustal fraction of moment of inertia in pulsars
International Nuclear Information System (INIS)
Atta, Debasis; Mukhopadhyay, Somnath; Basu, D.N.
2015-01-01
In the present work, stability of the β-equilibrated dense nuclear matter is analyzed with respect to the thermodynamic stability conditions. Based on the density dependent M3Y (DDM3Y) effective nucleon-nucleon (NN) interaction, the location of the inner edge of neutron star crusts and core-crust transition density and pressure are calculated and crustal fraction of moment of inertia is determined. These results for pressure and density at core-crust transition together with the observed minimum crustal fraction of the total moment of inertia provide a new limit for the radius of the Vela pulsar
Closure for spent-fuel transport and storage containers
International Nuclear Information System (INIS)
Ahner, S.; Knackstedt, H.G.; Srostlik, P.
1980-01-01
The container has a transport closure and a shielding closure. This shielding closure consists of two pieces (double closure system), which can be fartened to one another like a bayonet fixing. A central motion of rotation is enough to open the closure. It can be done remote-controlled as well as manually. (DG) [de
Classification and closure properties of languages for describing concurrent system behaviours
Energy Technology Data Exchange (ETDEWEB)
Szijarto, M.
1981-01-01
The correspondence between sequential program schemes and formal languages is well known. The situation is more complicated in the case of parallel program schemes, and trace languages have been introduced to describe them. The author introduces the concept of the closure of a language on a so called independence relation on the alphabet of the language, and formulate several theorems about them and the trace languages. He investigates the closedness properties of Chomsky classes under closure on independence relations, and as a special case we derive a new necessary and sufficient condition for the regularity of the commutative closure of a language. 12 references.
Transitional nuclei near shell closures
Energy Technology Data Exchange (ETDEWEB)
Mukherjee, G. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064 (India); Pai, H. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064, India and Present Address: Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstrasse 9, 64289 Darmstadt (Germany)
2014-08-14
High spin states in Bismuth and Thallium nuclei near the Z = 82 shell closure and Cesium nuclei near the N = 82 shell closure in A = 190 and A = 130 regions, respectively, have been experimentally investigated using heavy-ion fusion evaporation reaction and by detecting the gamma rays using the Indian National Gamma Array (INGA). Interesting shape properties in these transitional nuclei have been observed. The results were compared with the neighboring nuclei in these two regions. The total Routhian surface (TRS) calculations have been performed for a better understanding of the observed properties. In mass region A = 190, a change in shape from spherical to deformed has been observd around neutron number N = 112 for the Bi (Z = 83) isotopes with proton number above the magic gap Z = 82, whereas, the shape of Tl (Z = 81) isotopes with proton number below the magic gap Z = 82 remains stable as a function of neutron number. An important transition from aplanar to planar configuration of angular momentum vectors leading to the occurance of nuclar chirality and magnetic rotation, respectively, has been proposed for the unique parity πh{sub 11/2}⊗νh{sub 11/2} configuration in Cs isotopes in the mass region A ∼ 130 around neutron number N = 79. These results are in commensurate with the TRS calculations.
Criticality assessment of LLRWDF closure
International Nuclear Information System (INIS)
Sarrack, A.G.; Weber, J.H.; Woody, N.D.
1992-01-01
During the operation of the Low Level Radioactive Waste Disposal Facility (LLRWDF), large amounts (greater than 100 kg) of enriched uranium (EU) were buried. This EU came primarily from the closing and decontamination of the Naval Fuels Facility in the time period from 1987--1989. Waste Management Operations (WMO) procedures were used to keep the EU boxes separated to prevent possible criticality during normal operation. Closure of the LLRWDF is currently being planned, and waste stabilization by Dynamic Compaction (DC) is proposed. Dynamic compaction will crush the containers in the LLRWDF and result in changes in their geometry. Research of the LLRWDF operations and record keeping practices have shown that the EU contents of trenches are known, but details of the arrangement of the contents cannot be proven. Reviews of the trench contents, combined with analysis of potential critical configurations, revealed that some portions of the LLRWDF can be expected to be free of criticality concerns while other sections have credible probabilities for the assembly of a critical mass, even in the uncompacted configuration. This will have an impact on the closure options and which trenches can be compacted
Laboratory testing of closure cap repair techniques
International Nuclear Information System (INIS)
Persoff, P.; Moridis, G.; Tuck, D.M.
1996-10-01
Landfill design requires a low permeability closure cap as well as a low permeability liner. The Savannah River Site, in South Carolina, has approximately 85 acres of mixed waste landfills covered with compacted kaolin clay. Maintaining low permeability of the clay cap requires both that the permeability of the compacted clay itself remain low and that the integrity of the barrier be maintained. Barrier breaches typically result from penetration by roots or animals, and especially cracks caused by uneven settling or desiccation. In this study, clay layers, 0.81 m in diameter and 7.6 cm thick, were compacted in 7 lysimeters to simulate closure caps. The hydraulic conductivity of each layer was measured, and the compacted clay layers (CCL's) were cracked by drying. Then various repair techniques were applied and the effectiveness of each repair was assessed by remeasuring the hydraulic conductivity. Finally the repaired CCL was again dried and measured to determine how the repair responded to the conditions that caused the original failure. For a full report of this investigation see Persoff et al. Six repair techniques have been tested, four of which involve the use of injectable barrier liquids colloidal silica (CS) and polysiloxane (PSX) described below: (I) covering the crack with a bentonite geosynthetic clay liner (GCL), (ii) recompaction of new kaolinite at STD+3 moisture content joined to existing kaolinite that had dried and shrunk, (iii) direct injection of colloidal silica to a crack, (iv) injection of colloidal silica (CS) to wells in an overlying sand layer, (v) direct injection of polysiloxane to a crack, and (vi), injection of polysiloxane (PSX) to wells in an overlying soil layer
The Critical Moment of Transition
DEFF Research Database (Denmark)
Svalgaard, Lotte
2018-01-01
By providing a holding environment to acknowledge sensitivities and address emotions, leadership programmes prove to be powerful spaces for increasing self- and social awareness. However, the challenge is for one to maintain the newly gained self- and social awareness after leaving the holding...... – within the context of an international MBA program – of MBA students applying their knowledge from a Leadership Stream in an International Consultancy Project. This paper contributes to the theory and practice of management learning by providing lenses to understand subjective experiences of critical...... moments of transition, developing the notion of “mindful avoidance,” and pointing out a major and neglected potential space in the design of management education....
Theoretical and experimental studies for optimization of PCRV top closures
International Nuclear Information System (INIS)
Ottosen, N.S.; Andersen, S.I.
1975-01-01
The results from the remaining part of the parameter study and the preparations for the verification of an optimized design are presented. Three models have been made in the same scale and with the same depth to span ratio α as the low LM-3 model from the first investigation, i.e. α=0.35. The model LM-5 was provided with reinforcement in the tensile zone, the upper part of the closure. This reinforcement did not influence the stresses and strains in the load carrying concrete, and the dome failed at the same pressure as in the unreinforced model LM-3. However, the closure did not disintegrate, but failed due to large overall deformations causing seal leakage. In the model LM-6, the inverted dome, which is formed at higher loads as demonstrated in LM-3, was reinforced perpendicular to the supposed middle surface. This reinforcement proved to be effective, giving the dome a higher ultimate load capacity. The LM-6 test stopped due to a circumferential crack in the flange. Finally, the unreinforced LM-7 closure was tested to failure. Apart from minor changes in the flange, LM-7 was identical to LM-3 except for the excavated upper part of the concrete, which in LM-3 formed the heavily cracked tensile zone. The ultimate load and the failure mode observed for this closure were the same as for the LM-3. The experimental results are compared to finite element calculations, in which plasticity and cracking of the concrete are taken into account, and the influence of different material models for the concrete is investigated. A unique failure criterion, which includes failure of the concrete for both tensile and compressive stresses in the same mathematical expression, is proposed. Based on the results obtained from the parameter study, a new closure design is proposed, which is optimized with respect to the requirements at service conditions and ultimate load
Hospital closure: Phoenix, Hydra or Titanic?
Dunne, T; Davis, S
1996-01-01
Very little has been published about the effects of hospital closure in terms of the service, financial or management issues of the process. Attempts through a case-study format to redress the balance and as such represents the reflections of practitioners who have recently undergone the experience of hospital closure and the often neglected issues arising both during and after the process.
Key financial ratios can foretell hospital closures.
Lynn, M L; Wertheim, P
1993-11-01
An analysis of various financial ratios sampled from open and closed hospitals shows that certain leverage, liquidity, capital efficiency, and resource availability ratios can predict hospital closure up to two years in advance of the closure with an accuracy of nearly 75 percent.
2010-07-01
... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Use and Management of Containers § 264.178 Closure. At closure, all hazardous waste and hazardous waste residues must be removed...
Hanford Patrol Academy Demolition Sites Closure Plan
International Nuclear Information System (INIS)
1992-11-01
From 1975 to 1991 the Hanford Patrol Academy Demolition Sites (HPADS) were used for demolition events. These demolition events were a form of thermal treatment for spent or abandoned chemical waste. Because the HPADS will no longer be used for this thermal activity, the sites will be closed. Closure will be conducted pursuant to the requirements of the Washington State Department of Ecology (Ecology) Dangerous Waste Regulations, Washington Administrative Code (WAC) 173-303-610 and 40 CFR 270.1. Closure also will satisfy closure requirements of WAC 173-303-680 and for the thermal treatment closure requirements of 40 CFR 265.381. This closure plan presents a description of the HPADS, the history of the waste treated, and the approach that will be followed to close the HPADS. Because dangerous waste does not include the source, special nuclear, and by-product material components of mixed waste, radionuclides are not within the scope of WAC 173-303 or of this closure plan. The information on radionuclides is provided only for general knowledge where appropriate. Only dangerous constituents derived from HPADS operations will be addressed in this closure plan in accordance with WAC 173-303-610(2)(b)(i). The HPADS are actually two distinct soil closure areas within the Hanford Patrol Academy training area
Calculation of Post-Closure Natural Convection Heat and Mass Transfer in Yucca Mountain Drifts
International Nuclear Information System (INIS)
Webb, S.; Itamura, M.
2004-01-01
Natural convection heat and mass transfer under post-closure conditions has been calculated for Yucca Mountain drifts using the computational fluid dynamics (CFD) code FLUENT. Calculations have been performed for 300, 1000, 3000, and 10,000 years after repository closure. Effective dispersion coefficients that can be used to calculate mass transfer in the drift have been evaluated as a function of time and boundary temperature tilt
When the Battle is Lost and Won: Delayed Chest Closure After Bilateral Lung Transplantation.
Soresi, Simona; Sabashnikov, Anton; Weymann, Alexander; Zeriouh, Mohamed; Simon, André R; Popov, Aron-Frederik
2015-10-12
In this article we summarize benefits of delayed chest closure strategy in lung transplantation, addressing indications, different surgical techniques, and additional perioperative treatment. Delayed chest closure seems to be a valuable and safe strategy in managing patients with various conditions after lung transplantation, such as instable hemodynamics, need for high respiratory pressures, coagulopathy, and size mismatch. Therefore, this approach should be considered in lung transplant centers to give patients time to recover before the chest is closed.
Some Recent Developments in Turbulence Closure Modeling
Durbin, Paul A.
2018-01-01
Turbulence closure models are central to a good deal of applied computational fluid dynamical analysis. Closure modeling endures as a productive area of research. This review covers recent developments in elliptic relaxation and elliptic blending models, unified rotation and curvature corrections, transition prediction, hybrid simulation, and data-driven methods. The focus is on closure models in which transport equations are solved for scalar variables, such as the turbulent kinetic energy, a timescale, or a measure of anisotropy. Algebraic constitutive representations are reviewed for their role in relating scalar closures to the Reynolds stress tensor. Seamless and nonzonal methods, which invoke a single closure model, are reviewed, especially detached eddy simulation (DES) and adaptive DES. Other topics surveyed include data-driven modeling and intermittency and laminar fluctuation models for transition prediction. The review concludes with an outlook.
Noncommutative QED and anomalous dipole moments
International Nuclear Information System (INIS)
Riad, I.F.; Sheikh-Jabbari, M.M.
2000-09-01
We study QED on noncommutative spaces, NCQED. In particular we present the detailed calculation for the noncommutative electron-photon vertex and show that the Ward identity is satisfied. We discuss that in the noncommutative case moving electron will show electric dipole effects. In addition, we work out the electric and magnetic dipole moments up to one loop level. For the magnetic moment we show that noncommutative electron has an intrinsic (spin independent) magnetic moment. (author)
Electric dipole moment of diatomic molecules
International Nuclear Information System (INIS)
Rosato, A.
1983-01-01
The electric dipole moment of some diatomic molecules is calculated using the Variational Cellular Method. The results obtained for the molecules CO, HB, HF and LiH are compared with other calculations and with experimental data. It is shown that there is strong dependence of the electric dipole moment with respect to the geometry of the cells. It is discussed the possibility of fixing the geometry of the problem by giving the experimental value of the dipole moment. (Author) [pt
Electric dipole moment of diatomic molecules
International Nuclear Information System (INIS)
Rosato, A.
1983-01-01
The electric dipole moment of some diatomic molecules is calculated using the Variational Cellular Method. The results obtained for the CO, HB, HF and LiH molecules are compared with other calculations and with experimental data. It is shown that there is strong dependence of the electric dipole moment with respect to the geometry of the cells. The possibility of fixing the geometry of the problem by giving the experimental value of the dipole moment is discussed. (Author) [pt
Restrictions on the neutrino magnetic dipole moment
International Nuclear Information System (INIS)
Duncan, M.J.; Sankar, S.U.; Grifols, J.A.; Mendez, A.
1987-01-01
We examine mechanisms for producing neutrino magnetic moments from a wide class of particle theories which are extensions of the standard model. We show that it is difficult to naturally obtain a moment greater than ≅ 10 -2 electron Bohr magnetons. Thus models of phenomena requiring moments of order ≅ 10 -10 magnetons, such as those proposed as a resolution to the solar neutrino puzzle, are in conflict with current perceptions in particle physics. (orig.)
W-boson electric dipole moment
International Nuclear Information System (INIS)
He, X.; McKellar, B.H.J.
1990-01-01
The W-boson electric dipole moment is calculated in the SU(3) C xSU(2) L xU(1) Y model with several Higgs-boson doublets. Using the constraint on the CP-violating parameters from the experimental upper bound of the neutron electric dipole moment, we find that the W-boson electric dipole moment is constrained to be less than 10 -4
Study on a monitoring strategy to support decision making for geological repository closure
International Nuclear Information System (INIS)
Suyama, Yasuhiro; Tanabe, Hiromi; Eto, Jiro; Yoshimura, Kimitaka
2010-01-01
Japan currently plans to dispose of high-level radioactive wastes (vitrified HLWs) produced from the reprocessing of spent nuclear fuel in deep geological formations, in order to isolate the radioactive wastes from the human environment for tens of thousands of years. Such a geological repository must be designed to ensure operational safety and post-closure safety. Then, following the closure of the geological repository, post-closure safety will be provided by an engineered barrier system (EBS) and a natural barrier system (NBS) without relying on monitoring or institutional control. However, from a technical standpoint, monitoring has been required during backfilling in current studies. Additionally, there has been strong social pressure to continue monitoring during all the phases including post-closure. On the basis of the current situations, a monitoring strategy for geological disposal must be studied to ensure the long term safety of geological disposal. Focusing on decision making for geological repository closure, the authors have created a basic logical structure for the decision making process with the principles for ensuring safety and have developed a monitoring strategy based on the logical structure. The monitoring strategy is founded on three key aspects: the role of monitoring, boundary conditions of monitoring at the time of decision making, and a methodology for monitoring planning. Then, the monitoring strategy becomes a starting point of monitoring planning during site characterization, construction, operation and staged closure, as well as post-closure with institutional control, and of social science studies. (author)
How to introduce the magnetic dipole moment
International Nuclear Information System (INIS)
Bezerra, M; Kort-Kamp, W J M; Cougo-Pinto, M V; Farina, C
2012-01-01
We show how the concept of the magnetic dipole moment can be introduced in the same way as the concept of the electric dipole moment in introductory courses on electromagnetism. Considering a localized steady current distribution, we make a Taylor expansion directly in the Biot-Savart law to obtain, explicitly, the dominant contribution of the magnetic field at distant points, identifying the magnetic dipole moment of the distribution. We also present a simple but general demonstration of the torque exerted by a uniform magnetic field on a current loop of general form, not necessarily planar. For pedagogical reasons we start by reviewing briefly the concept of the electric dipole moment. (paper)
Gross shell structure of moments of inertia
International Nuclear Information System (INIS)
Deleplanque, M.A.; Frauendorf, S.; Pashkevich, V.V.; Chu, S.Y.; Unzhakova, A.
2002-01-01
Average yrast moments of inertia at high spins, where the pairing correlations are expected to be largely absent, were found to deviate from the rigid-body values. This indicates that shell effects contribute to the moment of inertia. We discuss the gross dependence of moments of inertia and shell energies on the neutron number in terms of the semiclassical periodic orbit theory. We show that the ground-state shell energies, nuclear deformations and deviations from rigid-body moments of inertia are all due to the same periodic orbits
Analysis of scaled-factorial-moment data
International Nuclear Information System (INIS)
Seibert, D.
1990-01-01
We discuss the two standard constructions used in the search for intermittency, the exclusive and inclusive scaled factorial moments. We propose the use of a new scaled factorial moment that reduces to the exclusive moment in the appropriate limit and is free of undesirable multiplicity correlations that are contained in the inclusive moment. We show that there are some similarities among most of the models that have been proposed to explain factorial-moment data, and that these similarities can be used to increase the efficiency of testing these models. We begin by calculating factorial moments from a simple independent-cluster model that assumes only approximate boost invariance of the cluster rapidity distribution and an approximate relation among the moments of the cluster multiplicity distribution. We find two scaling laws that are essentially model independent. The first scaling law relates the moments to each other with a simple formula, indicating that the different factorial moments are not independent. The second scaling law relates samples with different rapidity densities. We find evidence for much larger clusters in heavy-ion data than in light-ion data, indicating possible spatial intermittency in the heavy-ion events
Closure for milliliter scale bioreactor
Klein, David L.; Laidlaw, Robert D.; Andronaco, Gregory; Boyer, Stephen G.
2010-12-14
A closure for a microreactor includes a cap that is configured to be inserted into a well of the microreactor. The cap, or at least a portion of the cap, is compliant so as to form a seal with the well when the cap is inserted. The cap includes an aperture that provides an airway between the inside of the well to the external environment when the cap is inserted into the well. A porous plug is inserted in the aperture, e.g., either directly or in tube that extends through the aperture. The porous plug permits gas within the well to pass through the aperture while preventing liquids from passing through to reduce evaporation and preventing microbes from passing through to provide a sterile environment. A one-way valve may also be used to help control the environment in the well.
Closure of Microcosm for refurbishment
2014-01-01
Since 1994, the Microcosm exhibition has given the opportunity to visitors of all ages and backgrounds to have a first glimpse into the secrets of physics. To ensure that Microcosm can continue fulfilling its educational aims at the same level of quality for many years to come, it is closing for renovation work on 8 December 2014 and is expected to reopen during Summer 2015. During the closure, the “Fun with Physics” workshop will not take place, but the Universe of Particles exhibition in the Globe and the Passport to the Big Bang circuit will remain accessible to the public, free of charge and with no need to book in advance. Guided tours of CERN are also available (advance booking required via this page).
The neutron electric dipole moment
International Nuclear Information System (INIS)
He, X.G.; McKellar, B.H.J.; Pakvasa, S.
1989-01-01
A systematic study was made of the electric dipole moment (EDM) of neutron D n in various models of CP violation. It was found that in the standard KM model with 3 families the neutron EDM is in the range 1.4x10 -33 ≤ D n ≤ 1.6x10 -31 ecm; that the two Higgs doublet model has approximately the same value of D n as the standard model; that D n in the Weinberg model is predicted to satisfy D n > 10 -25 ecm; that in a class of left-right symmetric models D n is of the order of 10 -26-11 ecm; that in supersymmetric models D n is of the order 10 -22 φ ecm with φ being the possible phase difference of the phases of gluino mass and the gluino-quark-smark mixing matrix and that the strong CP parameter θ is found to be θ -9 , using the present experimental limit that D n -25 ecm with 90% confidence. 65 refs., 10 figs
Stereo Correspondence Using Moment Invariants
Premaratne, Prashan; Safaei, Farzad
Autonomous navigation is seen as a vital tool in harnessing the enormous potential of Unmanned Aerial Vehicles (UAV) and small robotic vehicles for both military and civilian use. Even though, laser based scanning solutions for Simultaneous Location And Mapping (SLAM) is considered as the most reliable for depth estimation, they are not feasible for use in UAV and land-based small vehicles due to their physical size and weight. Stereovision is considered as the best approach for any autonomous navigation solution as stereo rigs are considered to be lightweight and inexpensive. However, stereoscopy which estimates the depth information through pairs of stereo images can still be computationally expensive and unreliable. This is mainly due to some of the algorithms used in successful stereovision solutions require high computational requirements that cannot be met by small robotic vehicles. In our research, we implement a feature-based stereovision solution using moment invariants as a metric to find corresponding regions in image pairs that will reduce the computational complexity and improve the accuracy of the disparity measures that will be significant for the use in UAVs and in small robotic vehicles.
Explanations pertaining to the Hip Joint Flexor Moment During the Stance Phase of Human Walking
DEFF Research Database (Denmark)
Simonsen, Erik B; Cappelen, Katrine L; Skorini, Ragnhild
2012-01-01
A hip joint flexor moment in the last half of the stance phase during walking has repeatedly been reported. However, the purpose of this moment remains uncertain and it is unknown how it is generated. Nine male subjects were instructed to walk at 4.5 km/h with their upper body in three different...... positions: normal, inclined and reclined. Net joint moments were calculated about the hip, knee and ankle joint. The peak hip joint flexor moment during late stance was significantly lower during inclined walking than in the two other conditions. During normal walking the iliacus muscle showed no or very...... weak activity and first at the transition from stance to swing. When walking reclined, a clear but rather low activity level of the iliacus muscle was seen in the first half of the stance phase, which could contribute to the hip moment. In the inclined condition the iliacus showed much increased...
Closed forms and multi-moment maps
DEFF Research Database (Denmark)
Madsen, Thomas Bruun; Swann, Andrew Francis
2013-01-01
We extend the notion of multi-moment map to geometries defined by closed forms of arbitrary degree. We give fundamental existence and uniqueness results and discuss a number of essential examples, including geometries related to special holonomy. For forms of degree four, multi-moment maps are gu...
Magnetic moment of single layer graphene rings
Margulis, V. A.; Karpunin, V. V.; Mironova, K. I.
2018-01-01
Magnetic moment of single layer graphene rings is investigated. An analytical expression for the magnetic moment as a function of the magnetic field flux through the one-dimensional quantum rings is obtained. This expression has the oscillation character. The oscillation period is equal to one flux quanta.
6-quark contribution to nuclear magnetic moments
International Nuclear Information System (INIS)
Ito, H.
1985-01-01
The magnetic moments of nuclei with LS closed shell +/-1 particle are calculated. Core polarization and meson exchange current are treated realistically in order to single out the 6-quark contribution. Overall agreement with experimental values is quite good. It is shown that the 6-quark system contributes to the respective iso-vector and iso-scalar moments with reasonable magnitudes
D-dimensional moments of inertia
International Nuclear Information System (INIS)
Bender, C.M.; Mead, L.R.
1995-01-01
We calculate the moments of inertia of D-dimensional spheres and spherical shells, where D is a complex number. We also examine the moments of inertia of fractional-dimensional geometrical objects such as the Cantor set and the Sierpinski carpet and their D-dimensional analogs. copyright 1995 American Association of Physics Teachers
Dynamical moments of inertia for superdeformed nuclei
International Nuclear Information System (INIS)
Obikhod, T.V.
1995-01-01
The method of quantum groups has been applied for calculation the dynamical moments of inertia for the yrast superdeformed bands in 194 Hg and 192 Hg as well as to calculation of the dynamical moments of inertia of superdeformed bands in 150 Gd and 148 Gd
Polarization electric dipole moment in nonaxial nuclei
International Nuclear Information System (INIS)
Denisov, V.Yu.; Davidovskaya, O.I.
1996-01-01
An expression for the macroscopic polarization electric dipole moment is obtained for nonaxial nuclei whose radii of the proton and neutron surfaces are related by a linear equation. Dipole transitions associated with the polarization electric dipole moment are analyzed for static and dynamical multipole deformations
Droplet-model electric dipole moments
International Nuclear Information System (INIS)
Myers, W.D.; Swiatecki, W.J.
1991-01-01
Denisov's recent criticism of the droplet-model formula for the dipole moment of a deformed nucleus as derived by Dorso et al., it shown to be invalid. This helps to clarify the relation of theory to the measured dipole moments, as discussed in the review article by Aberg et al. (orig.)
Teachable Moment: Google Earth Takes Us There
Williams, Ann; Davinroy, Thomas C.
2015-01-01
In the current educational climate, where clearly articulated learning objectives are required, it is clear that the spontaneous teachable moment still has its place. Authors Ann Williams and Thomas Davinroy think that instructors from almost any discipline can employ Google Earth as a tool to take advantage of teachable moments through the…
Space Closure with Loop Mechanics for Treatment of Bimaxillary Protrusion: A Case Report
Sanjay, N; Rajesh, R N G; Scindia, Rajat; Ajith, Sreedevi D
2015-01-01
This case report intends to highlight the space closure with tear drop loop mechanics for bimaxillary protrusion. Loops can be fabricated in a sectional or full arch wire, and closing loops are usually used in loop mechanics for extraction space closure. The major advantage of loop mechanics is the lack of friction between the bracket and arch wire during space closure. An adult patient with bimaxillary protrusion reported to the clinic. The patient was treated successfully by maximum retraction of maxillary and mandibular anterior teeth after extraction of all first premolars. Space closure was begun using a moment differential between posterior and anterior segments created by a Tear drop loop. Anterior teeth were moved with bodily movement, and no anchorage loss of the posterior segments was seen using a Tear drop loop spring. A stable result with normal over jet and overbite was achieved with retraction of maxillary and mandibular anterior teeth. With a Tear drop loop, individual biomechanical responses can be achieved, and it is possible to calculate force magnitude for every patient. PMID:26028908
Firl, G. J.; Randall, D. A.
2013-12-01
The so-called "assumed probability density function (PDF)" approach to subgrid-scale (SGS) parameterization has shown to be a promising method for more accurately representing boundary layer cloudiness under a wide range of conditions. A new parameterization has been developed, named the Two-and-a-Half ORder closure (THOR), that combines this approach with a higher-order turbulence closure. THOR predicts the time evolution of the turbulence kinetic energy components, the variance of ice-liquid water potential temperature (θil) and total non-precipitating water mixing ratio (qt) and the covariance between the two, and the vertical fluxes of horizontal momentum, θil, and qt. Ten corresponding third-order moments in addition to the skewnesses of θil and qt are calculated using diagnostic functions assuming negligible time tendencies. The statistical moments are used to define a trivariate double Gaussian PDF among vertical velocity, θil, and qt. The first three statistical moments of each variable are used to estimate the two Gaussian plume means, variances, and weights. Unlike previous similar models, plume variances are not assumed to be equal or zero. Instead, they are parameterized using the idea that the less dominant Gaussian plume (typically representing the updraft-containing portion of a grid cell) has greater variance than the dominant plume (typically representing the "environmental" or slowly subsiding portion of a grid cell). Correlations among the three variables are calculated using the appropriate covariance moments, and both plume correlations are assumed to be equal. The diagnosed PDF in each grid cell is used to calculate SGS condensation, SGS fluxes of cloud water species, SGS buoyancy terms, and to inform other physical parameterizations about SGS variability. SGS condensation is extended from previous similar models to include condensation over both liquid and ice substrates, dependent on the grid cell temperature. Implementations have been
Directory of Open Access Journals (Sweden)
Harryanto Wijaya
2012-09-01
Full Text Available Background: Anchorage is one of the major concerns in orthodontic space closure. Various methods have been proposed to enhance posterior anchorage in space closure such as headgear, Nance holding appliance, and micro implant as temporary anchorage devices. However, several issues such as patient's compliance, appliance effectiveness, and cost of the device become many clinicians concern. The differential moment concept in segmented arch is a technique that requires no patient compliance but can effectively manage posterior anchorage and avoid bite deepening by careful application of forces and moments. Purpose: The purpose of this case report is to show the use of differential moment concept in segmented arch technique to manage posterior anchorage and to avoid bite deepening. Case: A 21 years old female patient with protrusive teeth as her chief complaint was treated using fixed orthodontic appliance. Case management: The treatment included four first bicuspid extraction and space closure utilizing differential moment concept in segmented arch. Conclusion: It can be concluded that application of differential moment concept in segmented arch technique is a non invasive, compliance independent, effective, and cost efficient method to manage posterior anchorage and to avoid bite deepening.latar belakang: Penjangkaran merupakan salah satu aspek yang sering kali menjadi masalah dalam penutupan ruang pada perawatan ortodonti. Berbagai metode disarankan untuk memperkuat penjangkaran posterior dalam penutupan ruang seperti headgear, piranti penahan Nance, dan implan mikro sebagai alat penjangkar sementara. Namun demikian, beberapa hal seperti kerjasama pasien, efektivitas piranti, dan biaya dari alat-alat tersebut sering menjadi perhatian/pertimbangan bagi klinisi. Konsep momen diferensial pada segmented arch adalah suatu cara yang efektif untuk memperkuat penjangkaran dan menghindari pendalaman gigitan tanpa memerlukan kerjasama pasien. tujuan
On the fourth moment of Hecke Maass forms and the Random Wave Conjecture
Buttcane, Jack; Khan, Rizwanur
2016-01-01
Conditionally on the Generalized Lindel\\"of Hypothesis, we obtain an asymptotic for the fourth moment of Hecke Maass cusp forms of large Laplacian eigenvalue for the full modular group. This lends support to the Random Wave Conjecture.
Electric dipole moments of nanosolvated acid molecules in water clusters.
Guggemos, Nicholas; Slavíček, Petr; Kresin, Vitaly V
2015-01-30
The electric dipole moments of (H2O)nDCl (n=3-9) clusters have been measured by the beam-deflection method. Reflecting the (dynamical) charge distribution within the system, the dipole moment contributes information about the microscopic structure of nanoscale solvation. The addition of a DCl molecule to a water cluster results in a strongly enhanced susceptibility. There is evidence for a noticeable rise in the dipole moment occurring at n≈5-6. This size is consistent with predictions for the onset of ionic dissociation. Additionally, a molecular-dynamics model suggests that even with a nominally bound impurity an enhanced dipole moment can arise due to the thermal and zero-point motion of the proton and the water molecules. The experimental measurements and the calculations draw attention to the importance of fluctuations in defining the polarity of water-based nanoclusters and generally to the essential role played by motional effects in determining the response of fluxional nanoscale systems under realistic conditions.
Gravitational closure of matter field equations
Düll, Maximilian; Schuller, Frederic P.; Stritzelberger, Nadine; Wolz, Florian
2018-04-01
The requirement that both the matter and the geometry of a spacetime canonically evolve together, starting and ending on shared Cauchy surfaces and independently of the intermediate foliation, leaves one with little choice for diffeomorphism-invariant gravitational dynamics that can equip the coefficients of a given system of matter field equations with causally compatible canonical dynamics. Concretely, we show how starting from any linear local matter field equations whose principal polynomial satisfies three physicality conditions, one may calculate coefficient functions which then enter an otherwise immutable set of countably many linear homogeneous partial differential equations. Any solution of these so-called gravitational closure equations then provides a Lagrangian density for any type of tensorial geometry that features ultralocally in the initially specified matter Lagrangian density. Thus the given system of matter field equations is indeed closed by the so obtained gravitational equations. In contrast to previous work, we build the theory on a suitable associated bundle encoding the canonical configuration degrees of freedom, which allows one to include necessary constraints on the geometry in practically tractable fashion. By virtue of the presented mechanism, one thus can practically calculate, rather than having to postulate, the gravitational theory that is required by specific matter field dynamics. For the special case of standard model matter one obtains general relativity.
Early closure of postinfarction ventricular septal defects.
Martinelli, Luigi; Dottori, Vincenzo; Caputo, Enrico; Graffigna, Angelo; Pederzolli, Carlo
2003-05-01
According to the guidelines of the American College of Cardiology/American Heart Association early closure of postinfarction septal defects is now a class I indication although it still carries a relevant morbidity and mortality. The operative risk is related both to the critical hemodynamic conditions of the patient and to the technical difficulties posed by the friable tissue of the infarcted area. The most recent techniques involving the use of pericardial patches reinforced by acrylic glue have significantly reduced the hospital mortality. The aim of this study was to discuss the reliability of an aggressive, tissue-sparing surgical approach to this complication. We present a consecutive series of 12 patients operated upon between January 1998 and October 2001 within 12 hours of the onset of clinical evidence of postinfarction septal rupture. Repair was achieved with minimal septal debridement and the use of a large pericardial patch reinforced by a biological glue. Three cases of dehiscence required early reoperation with no hospital mortality. This procedure is technically feasible and allows early aggressive treatment of postinfarction septal rupture with satisfactory results.
Cyanoacrylate for Intraoral Wound Closure: A Possibility?
Directory of Open Access Journals (Sweden)
Parimala Sagar
2015-01-01
Full Text Available Wound closure is a part of any surgical procedure and the objective of laceration repair or incision closure is to approximate the edges of a wound so that natural healing process may occur. Over the years new biomaterials have been discovered as an alternate to conventional suture materials. Cyanoacrylate bioadhesives are one among them. They carry the advantages of rapid application, patient comfort, resistance to infection, hemostatic properties, and no suture removal anxiety. Hence this study was undertaken to study the effect of long chain cyanoacrylate as an adhesive for intraoral wound closure and also to explore its hemostatic and antibacterial effects. Isoamyl-2-cyanoacrylate (AMCRYLATE was used as the adhesive in the study. In conclusion isoamyl cyanoacrylate can be used for intraoral wound closure, as an alternative to sutures for gluing the mucoperiosteum to bone, for example, after impaction removal, periapical surgeries, and cleft repair. Its hemostatic and antibacterial activity has to be further evaluated.
Reliability assessment of underground shaft closure
International Nuclear Information System (INIS)
Fossum, A.F.; Munson, D.E.
1994-01-01
The intent of the WIPP, being constructed in the bedded geologic salt deposits of Southeastern New Mexico, is to provide the technological basis for the safe disposal of radioactive Transuranic (TRU) wastes generated by the defense programs of the United States. In determining this technological basis, advanced reliability and structural analysis techniques are used to determine the probability of time-to-closure of a hypothetical underground shaft located in an argillaceous salt formation and filled with compacted crushed salt. Before being filled with crushed salt for sealing, the shaft provides access to an underground facility. Reliable closure of the shaft depends upon the sealing of the shaft through creep closure and recompaction of crushed backfill. Appropriate methods are demonstrated to calculate cumulative distribution functions of the closure based on laboratory determined random variable uncertainty in salt creep properties
32 CFR 989.25 - Base closure and realignment.
2010-07-01
... 32 National Defense 6 2010-07-01 2010-07-01 false Base closure and realignment. 989.25 Section 989... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.25 Base closure and realignment. Base closure or realignment may entail special requirements for environmental analysis. The permanent base closure...
Transcatheter closure of ventricular septal defect with Occlutech Duct Occluder.
Atik-Ugan, Sezen; Saltik, Irfan Levent
2018-04-01
Patent ductus arteriosus occluders are used for transcatheter closure of ventricular septal defects, as well as for closure of patent ductus arteriosus. The Occlutech Duct Occluder is a newly introduced device for transcatheter closure of patent ductus arteriosus. Here, we present a case in which the Occlutech Duct Occluder was successfully used on a patient for the closure of a perimembraneous ventricular septal defect.
Occupancy estimation and the closure assumption
Rota, Christopher T.; Fletcher, Robert J.; Dorazio, Robert M.; Betts, Matthew G.
2009-01-01
1. Recent advances in occupancy estimation that adjust for imperfect detection have provided substantial improvements over traditional approaches and are receiving considerable use in applied ecology. To estimate and adjust for detectability, occupancy modelling requires multiple surveys at a site and requires the assumption of 'closure' between surveys, i.e. no changes in occupancy between surveys. Violations of this assumption could bias parameter estimates; however, little work has assessed model sensitivity to violations of this assumption or how commonly such violations occur in nature. 2. We apply a modelling procedure that can test for closure to two avian point-count data sets in Montana and New Hampshire, USA, that exemplify time-scales at which closure is often assumed. These data sets illustrate different sampling designs that allow testing for closure but are currently rarely employed in field investigations. Using a simulation study, we then evaluate the sensitivity of parameter estimates to changes in site occupancy and evaluate a power analysis developed for sampling designs that is aimed at limiting the likelihood of closure. 3. Application of our approach to point-count data indicates that habitats may frequently be open to changes in site occupancy at time-scales typical of many occupancy investigations, with 71% and 100% of species investigated in Montana and New Hampshire respectively, showing violation of closure across time periods of 3 weeks and 8 days respectively. 4. Simulations suggest that models assuming closure are sensitive to changes in occupancy. Power analyses further suggest that the modelling procedure we apply can effectively test for closure. 5. Synthesis and applications. Our demonstration that sites may be open to changes in site occupancy over time-scales typical of many occupancy investigations, combined with the sensitivity of models to violations of the closure assumption, highlights the importance of properly addressing
Special closures for steel drum shipping containers
International Nuclear Information System (INIS)
Bonzon, L.L.; Otts, J.V.
1976-01-01
The objective of this program was to develop special lid closures for typical, steel drum, radioactive material shipping containers. Previous experience and testing had shown that the existing container was adequate to withstand the required environmental tests for certification, but that the lid and closure were just marginally effective. Specifically, the lid closure failed to consistently maintain a tight seal between the container and the lid after drop tests, thus causing the package contents to be vulnerable in the subsequent fire test. Recognizing the deficiency, the United States Energy Research and Development Administration requested the development of new closure(s) which would: (1) be as strong and resistant to a drop as the bottom of the container; (2) have minimal economic impact on the overall container cost; (3) maximize the use of existing container designs; (4) consider crush loads; and (5) result in less dependence on personnel and loading procedures. Several techniques were evaluated and found to be more effective than the standard closure mechanism. Of these, three new closure techniques were designed, fabricated, and proven to be structurally adequate to provide containment when a 454-kg drum was drop tested from 9.14-m onto an unyielding surface. The three designs were: (1) a 152-mm long lid extension or skirt welded to the standard drum lid, (2) a separate inner lid, with 152-mm long skirt and (3) C-clamps used at the container-lid interface. Based upon structural integrity, economic impact, and minimal design change, the lid extension is the recommended special closure
Factors affecting closure of a temporary stoma.
Taylor, Claire; Varma, Sarah
2012-01-01
The purpose of the study was to examine time to reversal of a temporary ostomy, reasons for delayed closure, and patient satisfaction with the scheduling of their closure and related hospital care. Cross-sectional, descriptive study. The target population comprised patients who underwent creation of a temporary ostomy and reversal surgery within one National Health System Hospital Trust in the United Kingdom. The population served by this Trust are ethnically and socioeconomically diverse, predominantly living in urban areas around Greater London. Sixty-one persons who met inclusion criteria were identified. A two-step analytical process was undertaken. First, a literature review examining incidence and causes of delayed stoma closure was undertaken. Second, a postal survey of all patients who had had their stoma closed in 2009 was conducted. Respondents were allowed 2 weeks to complete and return the questionnaire. The survey instrument was developed locally and subjected to content validation using ostomy patients, surgical and nursing colleagues. It consisted of 9 questions querying time from original surgery to closure, reasons for delaying closure surgery beyond 12 weeks, and satisfaction with care. Twenty-seven patients returned their questionnaires, indicating they consented to participate; a response rate of 44%. Half of the respondents (n = 14 [52%]) underwent closure surgery within 6 months of stoma formation; the remaining 48% waited more than 6 months (median: 6.5 months, range: 1.5-26 months). Thirteen patients (48%) reported a delay in receiving their stoma closure; the main reason cited was the need for a course of adjuvant postoperative chemotherapy. Three quarters of respondents (22 [74%]) were satisfied with the overall care they received. Findings from this study suggest that stoma closure may be associated with fewest complications if performed before 12 weeks.
Exceptional closure of UNIQA office at CERN
HR Department
2009-01-01
The UNIQA office at CERN will be closed from Wednesday 18 February to Friday 20 February due to painting work. During this closure, the Headquarters of UNIQA in Geneva will remain at the disposal of the members. See details https://cern.ch/chis/UNIQA_Offices.asp The CERN office will re-open on Monday 23 February according to the normal schedule. We apologise for any inconvenience caused by this closure.
On multipole moments in general relativity
International Nuclear Information System (INIS)
Hoenselaers, C.
1986-01-01
In general situations, involving gravitational waves the question of multiple moments in general relativity restricts the author to stationary axisymmetric situations. Here it has been shown that multipole moments, a set of numbers defined at spatial infinity as far away from the source as possible, determine a solution of Einstein's equations uniquely. With the rather powerful methods for generating solutions one might hope to get solutions with predefined multipole moments. Before doing so, however, one needs an efficient algorithm for calculating the moments of a given solution. Chapter 2 deals with a conjecture pertaining to such a calculational procedure and shows it to be not true. There is another context in which multipole moments are important. Consider a system composed of several objects. To separate, if possible, the various parts of their interaction, one needs a definition for multipole moments of individual members of a many body system. In spite of the fact that there is no definition for individual moments, with the exception of mass and angular momentum, Chapter 3 shows what can be done for the double Kerr solution. The authors can identify various terms in he interaction of two aligned Kerr objects and show that gravitational spin-spin interaction is indeed proportional to the product of the angular momenta
Table of Nuclear Electric Quadrupole Moments
International Nuclear Information System (INIS)
Stone, N.J.
2013-12-01
This Table is a compilation of experimental measurements of static electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. To aid identification of the states, their excitation energy, half-life, spin and parity are given, along with a brief indication of the method and any reference standard used in the particular measurement. Experimental data from all quadrupole moment measurements actually provide a value of the product of the moment and the electric field gradient [EFG] acting at the nucleus. Knowledge of the EFG is thus necessary to extract the quadrupole moment. A single recommended value of the moment is given for each state, based, for each element, wherever possible, upon a standard reference moment for a nuclear state of that element studied in a situation in which the electric field gradient has been well calculated. For several elements one or more subsidiary reference EFG/moment references are required and their use is specified. The literature search covers the period to mid-2013. (author)
Theory of nuclear magnetic moments - LT-35
Energy Technology Data Exchange (ETDEWEB)
Kerman, A. K.
1952-09-15
The purpose of these notes is to give an account of some attempts at interpreting the observed values of nuclear magnetic moments. There is no attempt at a complete summary of the field as that would take much more space than is used here. In many cases the arguments are only outlined and references are given for those interested in further details. A discussion of the theory of nuclear magnetic moments necessitates many excursions into the details of the nuclear models because the magnetic moments have a direct bearing on the validity of these models. However the main emphasis here is on those features which tend to explain the magnetic moments and other evidence is not discussed unless it has a direct bearing on the problem. In the first part of the discussion the Shell Model of the nucleus is used, as this model seems to correlate a large body of data relating to the heavier nuclei. Included here are the modifications proposed to explain the fact that the experimental magnetic moments do not fit quantitatively with the exact predictions of the Shell Model. The next sections deal with some of the more drastic modifications introduced to explain the large nuclear quadrupole moments and the effect of these modifications on the magnetic moments. Finally we turn to more detailed investigations of the light nuclei, in particular the - Conjugate nuclei. (author)
Energy Technology Data Exchange (ETDEWEB)
Arima, Takashi, E-mail: tks@stat.nitech.ac.jp [Center for Social Contribution and Collaboration, Nagoya Institute of Technology (Japan); Mentrelli, Andrea, E-mail: andrea.mentrelli@unibo.it [Department of Mathematics and Research Center of Applied Mathematics (CIRAM), University of Bologna (Italy); Ruggeri, Tommaso, E-mail: tommaso.ruggeri@unibo.it [Department of Mathematics and Research Center of Applied Mathematics (CIRAM), University of Bologna (Italy)
2014-06-15
Molecular extended thermodynamics of rarefied polyatomic gases is characterized by two hierarchies of equations for moments of a suitable distribution function in which the internal degrees of freedom of a molecule is taken into account. On the basis of physical relevance the truncation orders of the two hierarchies are proven to be not independent on each other, and the closure procedures based on the maximum entropy principle (MEP) and on the entropy principle (EP) are proven to be equivalent. The characteristic velocities of the emerging hyperbolic system of differential equations are compared to those obtained for monatomic gases and the lower bound estimate for the maximum equilibrium characteristic velocity established for monatomic gases (characterized by only one hierarchy for moments with truncation order of moments N) by Boillat and Ruggeri (1997) (λ{sub (N)}{sup E,max})/(c{sub 0}) ⩾√(6/5 (N−1/2 )),(c{sub 0}=√(5/3 k/m T)) is proven to hold also for rarefied polyatomic gases independently from the degrees of freedom of a molecule. -- Highlights: •Molecular extended thermodynamics of rarefied polyatomic gases is studied. •The relation between two hierarchies of equations for moments is derived. •The equivalence of maximum entropy principle and entropy principle is proven. •The characteristic velocities are compared to those of monatomic gases. •The lower bound of the maximum characteristic velocity is estimated.
International Nuclear Information System (INIS)
Arima, Takashi; Mentrelli, Andrea; Ruggeri, Tommaso
2014-01-01
Molecular extended thermodynamics of rarefied polyatomic gases is characterized by two hierarchies of equations for moments of a suitable distribution function in which the internal degrees of freedom of a molecule is taken into account. On the basis of physical relevance the truncation orders of the two hierarchies are proven to be not independent on each other, and the closure procedures based on the maximum entropy principle (MEP) and on the entropy principle (EP) are proven to be equivalent. The characteristic velocities of the emerging hyperbolic system of differential equations are compared to those obtained for monatomic gases and the lower bound estimate for the maximum equilibrium characteristic velocity established for monatomic gases (characterized by only one hierarchy for moments with truncation order of moments N) by Boillat and Ruggeri (1997) (λ (N) E,max )/(c 0 ) ⩾√(6/5 (N−1/2 )),(c 0 =√(5/3 k/m T)) is proven to hold also for rarefied polyatomic gases independently from the degrees of freedom of a molecule. -- Highlights: •Molecular extended thermodynamics of rarefied polyatomic gases is studied. •The relation between two hierarchies of equations for moments is derived. •The equivalence of maximum entropy principle and entropy principle is proven. •The characteristic velocities are compared to those of monatomic gases. •The lower bound of the maximum characteristic velocity is estimated
ASD Closure in Structural Heart Disease.
Wiktor, Dominik M; Carroll, John D
2018-04-17
While the safety and efficacy of percutaneous ASD closure has been established, new data have recently emerged regarding the negative impact of residual iatrogenic ASD (iASD) following left heart structural interventions. Additionally, new devices with potential advantages have recently been studied. We will review here the potential indications for closure of iASD along with new generation closure devices and potential late complications requiring long-term follow-up. With the expansion of left-heart structural interventions and large-bore transseptal access, there has been growing experience gained with management of residual iASD. Some recently published reports have implicated residual iASD after these procedures as a potential source of diminished clinical outcomes and mortality. Additionally, recent trials investigating new generation closure devices as well as expanding knowledge regarding late complications of percutaneous ASD closure have been published. While percutaneous ASD closure is no longer a novel approach to managing septal defects, there are several contemporary issues related to residual iASD following large-bore transseptal access and new generation devices which serve as an impetus for this review. Ongoing attention to potential late complications and decreasing their incidence with ongoing study is clearly needed.
Percutaneous Transcatheter PDA Device Closure in Infancy
International Nuclear Information System (INIS)
Ullah, M.; Sultan, M.; Akhtar, K.; Sadiq, N.; Akbar, H.
2014-01-01
Objective: To evaluate the results and complications associated with transcatheter closure of patent ductus arteriosus (PDA) in infants. Study Design: Quasi-experimental study. Place and Duration of Study: Paediatric Cardiology Department of Armed Forces Institute of Cardiology / National Institute of Heart Diseases (AFIC/NIHD), Rawalpindi, from December 2010 to June 2012. Methodology: Infants undergoing transcatheter device closure of PDA were included. All patients were evaluated by experienced Paediatric Cardiologists with 2-D echocardiography and Doppler before the procedure. Success of closure and complications were recorded. Results: The age of patients varied from 05 - 12 months and 31 (56.4%) were females. Out of the 55 infants, 3 (5.4%) were not offered device closure after aortogram (two large tubular type ducts and one tiny duct, considered unsuitable for device closure); while in 50 (96.1%) patients out of remaining 52, the duct was successfully closed with transcatheter PDA device or coil. In one infant, device deployment resulted in acquired coarctation, necessitating device retrieval by Snare followed by surgical duct interruption and another patient had non-fatal cardiac arrest during device deployment leading to abandonment of procedure and subsequent successful surgical interruption. Local vascular complications occurred in 12 (21.8%) of cases and all were satisfactorily treated. Conclusion: Transcatheter device closure of PDA in infants was an effective procedure in the majority of cases; however, here were considerable number of local access site vascular complications. (author)
Higher Moments of Underlying Event Distributions
Xu, Zhen
2017-01-01
We perform an Underlying Event analysis for real data sets from pp collisions at center of mass energy $ \\sqrt{s}=5 $ and 13 TeV and pPb collisions at $ \\sqrt{s}=7 $ TeV at the LHC, together with the Monte Carlo data sets generated with Pythia8 and EPOS in the same conditions. The analysis is focused on the transverse region which is more sensitive to the Underlying Event, and performed as a function of the leading track transverse - momentum $p_t$ in each event. In our work, not only the average underlying event activity but also its fluctuation, namely its root mean square (RMS), Skewness and Kurtosis, are analyzed. We find that the particle density, energy density and their fluctuation magnitude (RMS) are suppressed at leading $p_t\\approx$ 5 GeV/c for all these cases, with EPOS having evident deviation of 10\\%-25\\%. The higher moments skewness and kurtosis decrease rapidly in low leading $p_t$ region, and follow an interesting Gaussian-like peak centered at leading $p_t\\approx$ 15 GeV/c.
Moments analysis of concurrent Poisson processes
International Nuclear Information System (INIS)
McBeth, G.W.; Cross, P.
1975-01-01
A moments analysis of concurrent Poisson processes has been carried out. Equations are given which relate combinations of distribution moments to sums of products involving the number of counts associated with the processes and the mean rate of the processes. Elimination of background is discussed and equations suitable for processing random radiation, parent-daughter pairs in the presence of background, and triple and double correlations in the presence of background are given. The theory of identification of the four principle radioactive series by moments analysis is discussed. (Auth.)
Exchange currents for hypernuclear magnetic moments
International Nuclear Information System (INIS)
Saito, K.; Oka, M.; Suzuki, T.
1997-01-01
The meson (K and π) exchange currents for the hypernuclear magnetic moments are calculated using the effective Lagrangian method. The seagull diagram, the mesonic diagram and the Σ 0 -excitation diagram are considered. The Λ-N exchange magnetic moments for 5 Λ He and A=6 hypernuclei are calculated employing the harmonic oscillator shell model. It is found that the two-body correction is about -9% of the single particle value for 5 Λ He. The π exchange current, induced only in the Σ 0 -excitation diagram, is found to give dominant contribution for the isovector magnetic moments of hypernuclei with A=6. (orig.)
Moment analysis of hadronic vacuum polarization
Directory of Open Access Journals (Sweden)
Eduardo de Rafael
2014-09-01
Full Text Available I suggest a new approach to the determination of the hadronic vacuum polarization (HVP contribution to the anomalous magnetic moment of the muon aμHVP in lattice QCD. It is based on properties of the Mellin transform of the hadronic spectral function and their relation to the HVP self-energy in the Euclidean. I show how aμHVP is very well approximated by a few moments associated to this Mellin transform and how these moments can be evaluated in lattice QCD, providing thus a series of tests when compared with the corresponding determinations using experimental data.
Moment analysis of hadronic vacuum polarization
International Nuclear Information System (INIS)
Rafael, Eduardo de
2014-01-01
I suggest a new approach to the determination of the hadronic vacuum polarization (HVP) contribution to the anomalous magnetic moment of the muon a μ HVP in lattice QCD. It is based on properties of the Mellin transform of the hadronic spectral function and their relation to the HVP self-energy in the Euclidean. I show how a μ HVP is very well approximated by a few moments associated to this Mellin transform and how these moments can be evaluated in lattice QCD, providing thus a series of tests when compared with the corresponding determinations using experimental data
Moment analysis of hadronic vacuum polarization
Energy Technology Data Exchange (ETDEWEB)
Rafael, Eduardo de
2014-09-07
I suggest a new approach to the determination of the hadronic vacuum polarization (HVP) contribution to the anomalous magnetic moment of the muon a{sub μ}{sup HVP} in lattice QCD. It is based on properties of the Mellin transform of the hadronic spectral function and their relation to the HVP self-energy in the Euclidean. I show how a{sub μ}{sup HVP} is very well approximated by a few moments associated to this Mellin transform and how these moments can be evaluated in lattice QCD, providing thus a series of tests when compared with the corresponding determinations using experimental data.
Moment approach to charged particle beam dynamics
International Nuclear Information System (INIS)
Channell, P.J.
1983-01-01
We have derived the hierarchy of moment equations that describes the dynamics of charged-particle beams in linear accelerators and can truncate the hierarchy at any level either by discarding higher moments or by a cumulant expansion discarding only correlation functions. We have developed a procedure for relating the density expansion linearly to the moments to any order. The relation of space-charge fields to the density has been derived; and an accurate, systematic, and computationally convenient expansion of the resultant integrals has been developed
Dipole moments of the rho meson
International Nuclear Information System (INIS)
Hecht, M.B.; McKellar, B.H.P.
1997-04-01
The electric and magnetic dipole moments (EDM) of the rho meson are calculated using the propagators and vertices derived from the quantum chromodynamics Dyson-Schwinger equations. Results obtained from using the Bethe-Salpeter amplitude studied by Chappell, Mitchell et. al., and Pichowsky and Lee, are compared. The rho meson EDM is generated through the inclusion of a quark electric dipole moment, which is left as a free variable. These results are compared to the perturbative results to obtain a measure of the effects of quark interactions and confinement. The two dipole moments are also calculated using the phenomenological MIT bag model to provide a further basis for comparison
Moments method in the theory of accelerators
International Nuclear Information System (INIS)
Perel'shtejn, Eh.A.
1984-01-01
The moments method is widely used for solution of different physical and calculation problems in the theory of accelerators, magnetic optics and dynamics of high-current beams. Techniques using moments of the second order-mean squape characteristics of charged particle beams is shown to be most developed. The moments method is suitable and sometimes even the only technique applicable for solution of computerized problems on optimization of accelerating structures, beam transport channels, matching and other systems with accout of a beam space charge
105-DR Large Sodium Fire Facility closure activities evaluation report
International Nuclear Information System (INIS)
Adler, J.G.
1996-01-01
This report evaluates the closure activities at the 105-DR Large Sodium Fire Facility. The closure activities discussed include: the closure activities for the structures, equipment, soil, and gravel scrubber; decontamination methods; materials made available for recycling or reuse; and waste management. The evaluation compares these activities to the regulatory requirements and closure plan requirements. The report concludes that the areas identified in the closure plan can be clean closed
Primary closure in colon trauma.
Salinas-Aragón, Luis Enrique; Guevara-Torres, Lorenzo; Vaca-Pérez, Enrique; Belmares-Taboada, Jaime Arístides; Ortiz-Castillo, Fátima de Guadalupe; Sánchez-Aguilar, Martín
2009-01-01
Primary repair of colon injuries is an accepted therapeutic option; however, controversy persists regarding its safety. Our objective was to report the evolution and presence of complications in patients with colon injury who underwent primary closure and to determine if the time interval (>6 h), degree of injury, contamination, anatomic site injured, PATI (Penetrating Abdominal Trauma Index) >25, and the presence of other injuries in colon trauma are associated with increased morbidity and mortality. This was a prospective, observational, longitudinal and descriptive study conducted at the Central Hospital "Dr. Ignacio Morones Prieto," San Luis Potosí, Mexico, from January 1, 2003 to December 31, 2007. We included patients with abdominal trauma with colon injury subjected to surgical treatment. chi(2) was used for basic statistical analysis. There were 481 patients with abdominal trauma who underwent surgery; 77(16.1%) had colon injury. Ninety percent (n = 69) were treated in the first 6 h; 91% (n = 70) were due to penetrating injuries, and gunshot wound accounted for 48% (n = 37). Transverse colon was the most frequently injured (38%) (n = 29). Grade I and II injuries accounted for 75.3% (n = 58). Procedures included primary repair (76.66 %) (n = 46); resection with anastomosis (8.3%) (n = 5); and colostomy (15%) (n = 9). Associated injuries were present in 76.6% (n = 59). There was some degree of contamination in 85.7% (n = 66); 82.8% (58) had PATI colon injury. Primary repair is a safe procedure for treatment of colon injuries. Patients with primary repair had lower morbidity (p <0.009). Surgery during the first 6 h (p <0.006) and in hemodynamically stable patients (p <0.014) had a lower risk of complications.
Accelerating cleanup: Paths to closure
International Nuclear Information System (INIS)
1998-06-01
This report describes the status of Environmental Management's (EM's) cleanup program and a direction forward to complete achievement of the 2006 vision. Achieving the 2006 vision results in significant benefits related to accomplishing EM program objectives. As DOE sites accelerate cleanup activities, risks to public health, the environment, and worker safety and health are all reduced. Finding more efficient ways to conduct work can result in making compliance with applicable environmental requirements easier to achieve. Finally, as cleanup activities at sites are completed, the EM program can focus attention and resources on the small number of sites with more complex cleanup challenges. Chapter 1 describes the process by which this report has been developed and what it hopes to accomplish, its relationship to the EM decision-making process, and a general background of the EM mission and program. Chapter 2 describes how the site-by-site projections were constructed, and summarizes, for each of DOE's 11 Operations/Field Offices, the projected costs and schedules for completing the cleanup mission. Chapter 3 presents summaries of the detailed cleanup projections from three of the 11 Operations/Field Offices: Rocky Flats (Colorado), Richland (Washington), and Savannah River (South Carolina). The remaining eight Operations/Field Office summaries are in Appendix E. Chapter 4 reviews the cost drivers, budgetary constraints, and performance enhancements underlying the detailed analysis of the 353 projects that comprise EM's accelerated cleanup and closure effort. Chapter 5 describes a management system to support the EM program. Chapter 6 provides responses to the general comments received on the February draft of this document
On the Higher Moments of Particle Multiplicity, Chemical Freeze-Out, and QCD Critical Endpoint
Directory of Open Access Journals (Sweden)
A. Tawfik
2013-01-01
Full Text Available We calculate the first six nonnormalized moments of particle multiplicity within the framework of the hadron resonance gas model. In terms of the lower order moments and corresponding correlation functions, general expressions of higher order moments are derived. Thermal evolution of the first four normalized moments and their products (ratios are studied at different chemical potentials, so that it is possible to evaluate them at chemical freeze-out curve. It is found that a nonmonotonic behaviour reflecting the dynamical fluctuation and strong correlation of particles starts to appear from the normalized third order moment. We introduce novel conditions for describing the chemical freeze-out curve. Although the hadron resonance gas model does not contain any information on the criticality related to the chiral dynamics and singularity in the physical observables, we are able to find out the location of the QCD critical endpoint at μ ~ 350 MeV and temperature T ~ 162 MeV.
Moment stability for a predator-prey model with parametric dichotomous noises
Jin, Yan-Fei
2015-06-01
In this paper, we investigate the solution moment stability for a Harrison-type predator-prey model with parametric dichotomous noises. Using the Shapiro-Loginov formula, the equations for the first-order and second-order moments are obtained and the corresponding stable conditions are given. It is found that the solution moment stability depends on the noise intensity and correlation time of noise. The first-order and second-order moments become unstable with the decrease of correlation time. That is, the dichotomous noise can improve the solution moment stability with respect to Gaussian white noise. Finally, some numerical results are presented to verify the theoretical analyses. Project supported by the National Natural Science Foundation of China (Grant No. 11272051).
Nolan, Winifred P; See, Jovina L; Chew, Paul T K; Friedman, David S; Smith, Scott D; Radhakrishnan, Sunita; Zheng, Ce; Foster, Paul J; Aung, Tin
2007-01-01
To evaluate noncontact anterior segment optical coherence technology (AS-OCT) as a qualitative method of imaging the anterior chamber angle and to determine its ability to detect primary angle closure when compared with gonioscopy in Asian subjects. Prospective observational case series. Two hundred three subjects were recruited from glaucoma clinics in Singapore with diagnoses of primary angle closure, primary open-angle glaucoma, ocular hypertension, or cataract. Both eyes (if eligible) of each patient were included in the study. Exclusion criteria were pseudophakia or previous glaucoma surgery. Images of the nasal, temporal, and inferior angles were obtained with AS-OCT in dark and then light conditions. Gonioscopic angle width was graded using the Spaeth classification for each quadrant in low lighting conditions. Angle closure was defined by AS-OCT as contact between the peripheral iris and angle wall anterior to the scleral spur and by gonioscopy as a Spaeth grade of 0 degree (posterior trabecular meshwork not visible). Comparison of the 2 methods in detecting angle closure was done by eye and by individual. Sensitivities and specificities of AS-OCT were calculated using gonioscopy as the reference standard. Complete data were available for 342 eyes of 200 patients. Of the patients, 70.9% had a clinical diagnosis of treated or untreated primary angle closure. Angle closure in > or =1 quadrants was detected by AS-OCT in 142 (71%) patients (228 [66.7%] eyes) and by gonioscopy in 99 (49.5%) patients (152 [44.4%] eyes). The inferior angle was closed more frequently than the nasal or temporal quadrants using both AS-OCT and gonioscopy. When performed under dark conditions, AS-OCT identified 98% of those subjects found to have angle closure on gonioscopy (95% confidence interval [CI], 92.2-99.6) and led to the characterization of 44.6% of those found to have open angles on gonioscopy to have angle closure as well. With gonioscopy as the reference standard
Influence of lip closure on alveolar cleft width in patients with cleft lip and palate
Directory of Open Access Journals (Sweden)
Schmelzle Rainer
2011-01-01
Full Text Available Abstract Background The influence of surgery on growth and stability after treatment in patients with cleft lip and palate are topics still under discussion. The aim of the present study was to investigate the influence of early lip closure on the width of the alveolar cleft using dental casts. Methods A total of 44 clefts were investigated using plaster casts, 30 unilateral and 7 bilateral clefts. All infants received a passive molding plate a few days after birth. The age at the time of closure of the lip was 2.1 month in average (range 1-6 months. Plaster casts were obtained at the following stages: shortly after birth, prior to lip closure, prior to soft palate closure. We determined the width of the alveolar cleft before lip closure and prior to soft palate closure measuring the alveolar cleft width from the most lateral point of the premaxilla/anterior segment to the most medial point of the smaller segment. Results After lip closure 15 clefts presented with a width of 0 mm, meaning that the mucosa of the segments was almost touching one another. 19 clefts showed a width of up to 2 mm and 10 clefts were still over 2 mm wide. This means a reduction of 0% in 5 clefts, of 1-50% in 6 clefts, of 51-99% in 19 clefts, and of 100% in 14 clefts. Conclusions Early lip closure reduces alveolar cleft width. In most cases our aim of a remaining cleft width of 2 mm or less can be achieved. These are promising conditions for primary alveolar bone grafting to restore the dental bony arch.
Moments of inertia in a semiclassical approach
International Nuclear Information System (INIS)
Benchein, K.
1993-01-01
Semiclassical calculations have been performed for 31 nuclei. As a result of preliminary non-fully self-consistent calculations, the moments of inertia in investigated nuclei abd spin degrees of freedom are found
Anomalous magnetic moment with heavy virtual leptons
Energy Technology Data Exchange (ETDEWEB)
Kurz, Alexander [Karlsruher Institut fuer Technologie (Germany). Inst. fuer Theoretische Teilchenphysik; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Liu, Tao; Steinhauser, Matthias [Karlsruher Institut fuer Technologie (Germany). Inst. fuer Theoretische Teilchenphysik; Marquard, Peter [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)
2013-11-15
We compute the contributions to the electron and muon anomalous magnetic moment induced by heavy leptons up to four-loop order. Asymptotic expansion is applied to obtain three analytic expansion terms which show rapid convergence.
Calibration of TWSTFT Links Through the Triangle Closure Condition
2008-12-01
y Observatorio de la Armada, San Fernando, Spain SP Swedish National Testing and Research Institute in Borås, Sweden USNO US Naval Observatory in...accuracy for the realization of International Atomic Time,” Metrologia , 45, 185- 198. [5] D. Piester et al., 2006, “Calibration of six European TWSTFT
Droplet-model predictions of charge moments
International Nuclear Information System (INIS)
Myers, W.D.
1982-04-01
The Droplet Model expressions for calculating various moments of the nuclear charge distribution are given. There are contributions to the moments from the size and shape of the system, from the internal redistribution induced by the Coulomb repulsion, and from the diffuseness of the surface. A case is made for the use of diffuse charge distributions generated by convolution as an alternative to Fermi-functions
Moments of the very high multiplicity distributions
International Nuclear Information System (INIS)
Nechitailo, V.A.
2004-01-01
In experiment, the multiplicity distributions of inelastic processes are truncated due to finite energy, insufficient statistics, or special choice of events. It is shown that the moments of such truncated multiplicity distributions possess some typical features. In particular, the oscillations of cumulant moments at high ranks and their negative values at the second rank can be considered as ones most indicative of the specifics of these distributions. They allow one to distinguish between distributions of different type
Moment approach to tandem mirror radial transport
International Nuclear Information System (INIS)
Siebert, K.D.; Callen, J.D.
1986-02-01
A moment approach is proposed for the study of tandem mirror radial transport in the resonant plateau regime. The salient features of the method are described with reference to axisymmetric tokamak transport theory. In particular, the importance of momentum conservation to the establishment of the azimuthal variations in the electrostatic potential is demonstrated. Also, an ad hoc drift kinetic equation is solved to determine parallel viscosity coefficients which are required to close the moment system
Theoretical status of baryon magnetic moments
Franklin, Jerrold
1989-05-01
This talk given at the Eighth International Symposium on High-Energy Spin Physics in Minneapolis, Minnesota (September 12-17, 1988), is a short summary of theoretical results for baryon magnetic moments. Results from the static bag model and pion exchange effects are summarized and compared with experimental data. A list of references for various models and properties effecting the baryon magnetic moments is given at the end of the article. (AIP)
Theoretical status of baryon magnetic moments
International Nuclear Information System (INIS)
Franklin, J.
1989-01-01
This talk given at the Eighth International Symposium on High-Energy Spin Physics in Minneapolis, Minnesota (September 12--17, 1988), is a short summary of theoretical results for baryon magnetic moments. Results from the static bag model and pion exchange effects are summarized and compared with experimental data. A list of references for various models and properties effecting the baryon magnetic moments is given at the end of the article
From moments to functions in quantum chromodynamics
International Nuclear Information System (INIS)
Bluemlein, Johannes; Klein, Sebastian; Kauers, Manuel; Schneider, Carsten
2009-02-01
Single-scale quantities, like the QCD anomalous dimensions andWilson coefficients, obey difference equations. Therefore their analytic form can be determined from a finite number of moments. We demonstrate this in an explicit calculation by establishing and solving large scale recursions by means of computer algebra for the anomalous dimensions and Wilson coefficients in unpolarized deeply inelastic scattering from their Mellin moments to 3-loop order. (orig.)
Estimation of Uncertainties of Full Moment Tensors
2017-10-06
For our moment tensor inversions, we use the ‘cut-and-paste’ ( CAP ) code of Zhu and Helmberger (1996) and Zhu and Ben-Zion (2013), with some...modifications. For the misfit function we use an L1 norm Silwal and Tape (2016), and we incorporate the number of misfitting polarities into the waveform... norm of the eigenvalue triple provides the magnitude of the moment tensor, leaving two free parameters to define the source type. In the same year
Moments expansion densities for quantifying financial risk
Ñíguez, T.M.; Perote, J.
2017-01-01
We propose a novel semi-nonparametric distribution that is feasibly parameterized to represent the non-Gaussianities of the asset return distributions. Our Moments Expansion (ME) density presents gains in simplicity attributable to its innovative polynomials, which are defined by the difference between the nth power of the random variable and the nth moment of the density used as the basis. We show that the Gram-Charlier distribution is a particular case of the ME-type of densities. The latte...
From moments to functions in quantum chromodynamics
Energy Technology Data Exchange (ETDEWEB)
Bluemlein, Johannes; Klein, Sebastian [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Kauers, Manuel; Schneider, Carsten [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation
2009-02-15
Single-scale quantities, like the QCD anomalous dimensions andWilson coefficients, obey difference equations. Therefore their analytic form can be determined from a finite number of moments. We demonstrate this in an explicit calculation by establishing and solving large scale recursions by means of computer algebra for the anomalous dimensions and Wilson coefficients in unpolarized deeply inelastic scattering from their Mellin moments to 3-loop order. (orig.)
Flows, scaling, and the control of moment hierarchies for stochastic chemical reaction networks
Smith, Eric; Krishnamurthy, Supriya
2017-12-01
Stochastic chemical reaction networks (CRNs) are complex systems that combine the features of concurrent transformation of multiple variables in each elementary reaction event and nonlinear relations between states and their rates of change. Most general results concerning CRNs are limited to restricted cases where a topological characteristic known as deficiency takes a value 0 or 1, implying uniqueness and positivity of steady states and surprising, low-information forms for their associated probability distributions. Here we derive equations of motion for fluctuation moments at all orders for stochastic CRNs at general deficiency. We show, for the standard base case of proportional sampling without replacement (which underlies the mass-action rate law), that the generator of the stochastic process acts on the hierarchy of factorial moments with a finite representation. Whereas simulation of high-order moments for many-particle systems is costly, this representation reduces the solution of moment hierarchies to a complexity comparable to solving a heat equation. At steady states, moment hierarchies for finite CRNs interpolate between low-order and high-order scaling regimes, which may be approximated separately by distributions similar to those for deficiency-zero networks and connected through matched asymptotic expansions. In CRNs with multiple stable or metastable steady states, boundedness of high-order moments provides the starting condition for recursive solution downward to low-order moments, reversing the order usually used to solve moment hierarchies. A basis for a subset of network flows defined by having the same mean-regressing property as the flows in deficiency-zero networks gives the leading contribution to low-order moments in CRNs at general deficiency, in a 1 /n expansion in large particle numbers. Our results give a physical picture of the different informational roles of mean-regressing and non-mean-regressing flows and clarify the dynamical
Control of aperture closure during reach-to-grasp movements in Parkinson's disease.
Rand, M K; Smiley-Oyen, A L; Shimansky, Y P; Bloedel, J R; Stelmach, G E
2006-01-01
This study examined whether the pattern of coordination between arm-reaching toward an object (hand transport) and the initiation of aperture closure for grasping is different between PD patients and healthy individuals, and whether that pattern is affected by the necessity to quickly adjust the reach-to-grasp movement in response to an unexpected shift of target location. Subjects reached for and grasped a vertical dowel, the location of which was indicated by illuminating one of the three dowels placed on a horizontal plane. In control conditions, target location was fixed during the trial. In perturbation conditions, target location was shifted instantaneously by switching the illumination to a different dowel during the reach. The hand distance from the target at which the subject initiated aperture closure (aperture closure distance) was similar for both the control and perturbation conditions within each group of subjects. However, that distance was significantly closer to the target in the PD group than in the control group. The timing of aperture closure initiation varied considerably across the trials in both groups of subjects. In contrast, aperture closure distance was relatively invariant, suggesting that aperture closure initiation was determined by spatial parameters of arm kinematics rather than temporal parameters. The linear regression analysis of aperture closure distance showed that the distance was highly predictable based on the following three parameters: the amplitude of maximum grip aperture, hand velocity, and hand acceleration. This result implies that a control law, the arguments of which include the above parameters, governs the initiation of aperture closure. Further analysis revealed that the control law was very similar between the subject groups under each condition as well as between the control and perturbation conditions for each group. Consequently, the shorter aperture closure distance observed in PD patients apparently is a
Control of aperture closure during reach-to-grasp movements in parkinson’s disease
Rand, M. K.; Smiley-Oyen, A. L.; Shimansky, Y. P.; Bloedel, J. R.; Stelmach, G. E.
2007-01-01
This study examined whether the pattern of coordination between arm-reaching toward an object (hand transport) and the initiation of aperture closure for grasping is different between PD patients and healthy individuals, and whether that pattern is affected by the necessity to quickly adjust the reach-to-grasp movement in response to an unexpected shift of target location. Subjects reached for and grasped a vertical dowel, the location of which was indicated by illuminating one of the three dowels placed on a horizontal plane. In control conditions, target location was fixed during the trial. In perturbation conditions, target location was shifted instantaneously by switching the illumination to a different dowel during the reach. The hand distance from the target at which the subject initiated aperture closure (aperture closure distance) was similar for both the control and perturbation conditions within each group of subjects. However, that distance was significantly closer to the target in the PD group than in the control group. The timing of aperture closure initiation varied considerably across the trials in both groups of subjects. In contrast, aperture closure distance was relatively invariant, suggesting that aperture closure initiation was determined by spatial parameters of arm kinematics rather than temporal parameters. The linear regression analysis of aperture closure distance showed that the distance was highly predictable based on the following three parameters: the amplitude of maximum grip aperture, hand velocity, and hand acceleration. This result implies that a control law, the arguments of which include the above parameters, governs the initiation of aperture closure. Further analysis revealed that the control law was very similar between the subject groups under each condition as well as between the control and perturbation conditions for each group. Consequently, the shorter aperture closure distance observed in PD patients apparently is a
Djer, Mulyadi M; Idris, Nikmah S; Alwi, Idrus; Wijaya, Ika P
2014-07-01
Transcatheter closure of perimembranous and muscular ventricular septal defect (VSD) has been performed widely and it has more advantages compare to surgery. However, transcatheter closure of residual VSD post operation of complex congenital heart disease is still challenging because of the complexity of anatomy and concern about device stability, so the operator should meticulously choose the most appropriate technique and device. We would like to report a case of transcatheter closure of residual VSD post Rastelli operation in a patient with double outlet right ventricle (DORV), sub-aortic VSD, severe infundibulum pulmonary stenosis (PS) and single coronary artery. The patient had undergone operations for four times, but he still had intractable heart failure that did not response to medications. On the first attempt. we closed the VSD using a VSD occluder, unfortunately the device embolized into the descending aorta, but fortunately we was able to snare it out. Then we decided to close the VSD using a patent ductus arteriosus (PDA occluder). On transesophageal echocardiography (TEE) and angiography evaluation, the device position was stable. Post transcatheter VSD closure, the patient clinical condition improved significantly and he could finally be discharged after a long post-surgery hospitalization. Based on this experience we concluded that the transcatheter closure of residual VSD in complex CHD using PDA occluder could be an effective alternative treatment.
Exact collisional moments for plasma fluid theories
Pfefferle, David; Hirvijoki, Eero; Lingam, Manasvi
2017-10-01
The velocity-space moments of the often troublesome nonlinear Landau collision operator are expressed exactly in terms of multi-index Hermite-polynomial moments of the distribution functions. The collisional moments are shown to be generated by derivatives of two well-known functions, namely the Rosenbluth-MacDonald-Judd-Trubnikov potentials for a Gaussian distribution. The resulting formula has a nonlinear dependency on the relative mean flow of the colliding species normalised to the root-mean-square of the corresponding thermal velocities, and a bilinear dependency on densities and higher-order velocity moments of the distribution functions, with no restriction on temperature, flow or mass ratio of the species. The result can be applied to both the classic transport theory of plasmas, that relies on the Chapman-Enskog method, as well as to deriving collisional fluid equations that follow Grad's moment approach. As an illustrative example, we provide the collisional ten-moment equations with exact conservation laws for momentum- and energy-transfer rate.
40 CFR 264.228 - Closure and post-closure care.
2010-07-01
... remaining wastes to a bearing capacity sufficient to support final cover; and (iii) Cover the surface....112 must include both a plan for complying with paragraph (a)(1) of this section and a contingent plan... practicably removed at closure; and (ii) The owner or operator must prepare a contingent post-closure plan...
International Nuclear Information System (INIS)
Khan, A.W.; Maqsood, R.; Saleem, M.M.
2017-01-01
To compare the mean post-operative analgesic requirement in non-closure and closure of peritoneum during open appendectomy. Study Design: Randomized controlled trial. Place and Duration of Study: Department of General Surgery Combined Military Hospital Quetta, from 1st August 2014 to 30th April 2015. Material and Methods: A total of 60 patients were included in this study and were divided into two groups of 30 each. Patients in group A underwent open appendectomy with closure of peritoneum while patients in group B had non-closure of peritoneum during the same procedure. Post-operatively, pain severity was assessed on visual analogue scale (VAS) numeric pain distress scale. On presence of VAS numeric pain distress scale between 5 to 7, intramuscular (IM) diclofenac sodium was given and on score >7, intravascular (IV) tramadol was given. The final outcome was measured at day 0 and day 1. Results: Pain score and analgesic requirements were significantly less in non-closure group than closure group on day 0 and day 1, showing statistically significant difference between the two groups. Conclusion: Mean post-operative analgesic requirement is significantly less in non-closure group as compared to closure group during open appendectomy. (author)
Scalp Wound Closure with K wires: An alternative easier method to scalp wound closure.
Ramesh, S; Ajik, S
2012-12-01
Scalp defects and lacerations present a reconstructive challenge to plastic surgeons. Many methods have been described from the use of skin grafting to rotation flaps. Here we present a method of closure of a contaminated scalp wound with the use of Kirschner wires. In our case, closure of scalp laceration was made possible with the use of 1.4 Kirschner wires and cable tie/ zip tie fasteners. The duration to closure of wound was 10 days. In reconstructing the scalp defect, this method was found to adhere to principles of scalp reconstruction. There were no post operative complications found from the procedure. On initial application on the edge of the wound, tension applied caused the K wires to cut through the wound edge. On replacement of K wires 1cm away from wound edge the procedure was not plagued by any further complication. In conclusion we find scalp closure with Kirschner wires are a simple and effective method for scalp wound closure.
Performance Evaluation of Moment Connections of Moment Resisting Frames Against Progressive Collapse
Directory of Open Access Journals (Sweden)
M. Mahmoudi
2017-02-01
Full Text Available When a primary structural element fails due to sudden load such as explosion, the building undergoes progressive collapse. The method for design of moment connections during progressive collapse is different to seismic design of moment connections. Because in this case, the axial force on the connections makes it behave differently. The purpose of this paper is to evaluate the performance of a variety of moment connections in preventing progressive collapse in steel moment frames. To achieve this goal, three prequalified moment connections (BSEEP, BFP and WUP-W were designed according seismic codes. These moment connections were analyzed numerically using ABAQUS software for progressive collapse. The results show that the BFP connection (bolted flange plate has capacity much more than other connections because of the use of plates at the junction of beam-column.
End effects on elbows subjected to moment loadings
International Nuclear Information System (INIS)
Rodabaugh, E.C.; Moore, S.E.
1982-01-01
So-called end effects for moment loadings on short-radius and long-radius butt welding elbows of various arc lengths are investigated with a view toward providing more accurate design formulas for critical piping systems. Data developed in this study, along with published information, were used to develop relatively simple design equations for elbows attached at both ends to long sections of straight pipe. These formulas are the basis for an alternate ASME Code procedure for evaluating the bending moment stresses in Class 1 nuclear piping (ASME Code Case N-319). The more complicated problems of elbows with other end conditions, e.g., flanges at one or both ends, are also considered. Comparisons of recently published experimental and theoretical studies with current industrial code design rules for these situations indicate that these rules also need to be improved
Moment problems and the causal set approach to quantum gravity
International Nuclear Information System (INIS)
Ash, Avner; McDonald, Patrick
2003-01-01
We study a collection of discrete Markov chains related to the causal set approach to modeling discrete theories of quantum gravity. The transition probabilities of these chains satisfy a general covariance principle, a causality principle, and a renormalizability condition. The corresponding dynamics are completely determined by a sequence of non-negative real coupling constants. Using techniques related to the classical moment problem, we give a complete description of any such sequence of coupling constants. We prove a representation theorem: every discrete theory of quantum gravity arising from causal set dynamics satisfying covariance, causality, and renormalizability corresponds to a unique probability distribution function on the non-negative real numbers, with the coupling constants defining the theory given by the moments of the distribution
International Nuclear Information System (INIS)
Yu Mingzhou; Lin Jianzhong; Jin Hanhui; Jiang Ying
2011-01-01
The closure of moment equations for nanoparticle coagulation due to Brownian motion in the entire size regime is performed using a newly proposed method of moments. The equations in the free molecular size regime and the continuum plus near-continuum regime are derived separately in which the fractal moments are approximated by three-order Taylor-expansion series. The moment equations for coagulation in the entire size regime are achieved by the harmonic mean solution and the Dahneke’s solution. The results produced by the quadrature method of moments (QMOM), the Pratsinis’s log-normal moment method (PMM), the sectional method (SM), and the newly derived Taylor-expansion moment method (TEMOM) are presented and compared in accuracy and efficiency. The TEMOM method with Dahneke’s solution produces the most accurate results with a high efficiency than other existing moment models in the entire size regime, and thus it is recommended to be used in the following studies on nanoparticle dynamics due to Brownian motion.
Stomal Closure: Strategies to Prevent Incisional Hernia
Harries, Rhiannon L.; Torkington, Jared
2018-01-01
Incisional hernias following ostomy reversal occur frequently. Incisional hernias at the site of a previous stoma closure can cause significant morbidity, impaired quality of life, lead to life-threatening hernia incarceration or strangulation and result in a significant financial burden on health care systems Despite this, the evidence base on the subject is limited. Many recognised risk factors for the development of incisional hernia following ostomy reversal are related to patient factors such as age, malignancy, diabetes, COPD, hypertension and obesity, and are not easily correctable. There is a limited amount of evidence to suggest that prophylactic mesh reinforcement may be of benefit to reduce the post stoma closure incisional hernia rate but a further large scale randomised controlled trial is due to report in the near future. There appears to be weak evidence to suggest that surgeons should favour circular, or “purse-string” closure of the skin following stoma closure in order to reduce the risk of SSI, which in turn may reduce incisional hernia formation. There remains the need for further evidence in relation to suture technique, skin closure techniques, mechanical bowel preparation and oral antibiotic prescription focusing on incisional hernia development as an outcome measure. Within this review, we discuss in detail the evidence base for the risk factors for the development of, and the strategies to prevent ostomy reversal site incisional hernias. PMID:29670882
Angle closure glaucoma in congenital ectropion uvea
Directory of Open Access Journals (Sweden)
Grace M. Wang
2018-06-01
Full Text Available Purpose: Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. Observations: Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months and required additional surgery (cycloablation or trabeculectomy. Conclusions and importance: Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control. Keywords: Congenital ectropion uvea, Juvenile glaucoma, Angle-closure glaucoma, Glaucoma drainage device
Closure of shallow underground injection wells
International Nuclear Information System (INIS)
Veil, J.A.; Grunewald, B.
1993-01-01
Shallow injection wells have long been used for disposing liquid wastes. Some of these wells have received hazardous or radioactive wastes. According to US Environmental Protection Agency (EPA) regulations, Class IV wells are those injection wells through which hazardous or radioactive wastes are injected into or above an underground source of drinking water (USDW). These wells must be closed. Generally Class V wells are injection wells through which fluids that do not contain hazardous or radioactive wastes are injected into or above a USDW. Class V wells that are responsible for violations of drinking water regulations or that pose a threat to human health must also be closed. Although EPA regulations require closure of certain types of shallow injection wells, they do not provide specific details on the closure process. This paper describes the regulatory background, DOE requirements, and the steps in a shallow injection well closure process: Identification of wells needing closure; monitoring and disposal of accumulated substances; filling and sealing of wells; and remediation. In addition, the paper describes a major national EPA shallow injection well enforcement initiative, including closure plan guidance for wells used to dispose of wastes from service station operations
Stomal Closure: Strategies to Prevent Incisional Hernia
Directory of Open Access Journals (Sweden)
Rhiannon L. Harries
2018-04-01
Full Text Available Incisional hernias following ostomy reversal occur frequently. Incisional hernias at the site of a previous stoma closure can cause significant morbidity, impaired quality of life, lead to life-threatening hernia incarceration or strangulation and result in a significant financial burden on health care systems Despite this, the evidence base on the subject is limited. Many recognised risk factors for the development of incisional hernia following ostomy reversal are related to patient factors such as age, malignancy, diabetes, COPD, hypertension and obesity, and are not easily correctable. There is a limited amount of evidence to suggest that prophylactic mesh reinforcement may be of benefit to reduce the post stoma closure incisional hernia rate but a further large scale randomised controlled trial is due to report in the near future. There appears to be weak evidence to suggest that surgeons should favour circular, or “purse-string” closure of the skin following stoma closure in order to reduce the risk of SSI, which in turn may reduce incisional hernia formation. There remains the need for further evidence in relation to suture technique, skin closure techniques, mechanical bowel preparation and oral antibiotic prescription focusing on incisional hernia development as an outcome measure. Within this review, we discuss in detail the evidence base for the risk factors for the development of, and the strategies to prevent ostomy reversal site incisional hernias.
Strategic Planning for Hot Cell Closure
International Nuclear Information System (INIS)
LANGSTAFF, D.C.
2001-01-01
The United States Department of Energy (DOE) and its contractor were remediating a large hot cell complex to mitigate the radiological hazard. A Resource Conservation and Recovery Act (RCRA) closure unit was determined to be located within the complex. The regulator established a challenge to develop an acceptable closure plan on a short schedule (four months). The scope of the plan was to remove all excess equipment and mixed waste from the closure unit, establish the requirements of the legally binding Closure Plan and develop an acceptable schedule. The complex has several highly radioactive tanks, tank vaults, piping, and large hot cells containing complex chemical processing equipment. Driven by a strong need to develop an effective strategy to meet cleanup commitments, three principles were followed to develop an acceptable plan: (1) Use a team approach, (2) Establish a buffer zone to support closure, and (3) Use good practice when planning the work sequence. The team was composed of DOE, contractor, and Washington State Department of Ecology (Regulator) staff. The team approach utilized member expertise and fostered member involvement and communication. The buffer zone established an area between the unregulated parts of the building and the areas that were allegedly not in compliance with environmental standards. Introduction of the buffer zone provided simplicity, clarity, and flexibility into the process. Using good practice means using the DOE Integrated Safety Management Core Functions for planning and implementing work safely. Paying adequate attention to detail when the situation required contributed to the process credibility and a successful plan
Invariant hip moment pattern while walking with a robotic hip exoskeleton.
Lewis, Cara L; Ferris, Daniel P
2011-03-15
Robotic lower limb exoskeletons hold significant potential for gait assistance and rehabilitation; however, we have a limited understanding of how people adapt to walking with robotic devices. The purpose of this study was to test the hypothesis that people reduce net muscle moments about their joints when robotic assistance is provided. This reduction in muscle moment results in a total joint moment (muscle plus exoskeleton) that is the same as the moment without the robotic assistance despite potential differences in joint angles. To test this hypothesis, eight healthy subjects trained with the robotic hip exoskeleton while walking on a force-measuring treadmill. The exoskeleton provided hip flexion assistance from approximately 33% to 53% of the gait cycle. We calculated the root mean squared difference (RMSD) between the average of data from the last 15 min of the powered condition and the unpowered condition. After completing three 30-min training sessions, the hip exoskeleton provided 27% of the total peak hip flexion moment during gait. Despite this substantial contribution from the exoskeleton, subjects walked with a total hip moment pattern (muscle plus exoskeleton) that was almost identical and more similar to the unpowered condition than the hip angle pattern (hip moment RMSD 0.027, angle RMSD 0.134, p<0.001). The angle and moment RMSD were not different for the knee and ankle joints. These findings support the concept that people adopt walking patterns with similar joint moment patterns despite differences in hip joint angles for a given walking speed. Copyright © 2011 Elsevier Ltd. All rights reserved.
Data-driven non-Markovian closure models
Kondrashov, Dmitri; Chekroun, Mickaël D.; Ghil, Michael
2015-03-01
This paper has two interrelated foci: (i) obtaining stable and efficient data-driven closure models by using a multivariate time series of partial observations from a large-dimensional system; and (ii) comparing these closure models with the optimal closures predicted by the Mori-Zwanzig (MZ) formalism of statistical physics. Multilayer stochastic models (MSMs) are introduced as both a generalization and a time-continuous limit of existing multilevel, regression-based approaches to closure in a data-driven setting; these approaches include empirical model reduction (EMR), as well as more recent multi-layer modeling. It is shown that the multilayer structure of MSMs can provide a natural Markov approximation to the generalized Langevin equation (GLE) of the MZ formalism. A simple correlation-based stopping criterion for an EMR-MSM model is derived to assess how well it approximates the GLE solution. Sufficient conditions are derived on the structure of the nonlinear cross-interactions between the constitutive layers of a given MSM to guarantee the existence of a global random attractor. This existence ensures that no blow-up can occur for a broad class of MSM applications, a class that includes non-polynomial predictors and nonlinearities that do not necessarily preserve quadratic energy invariants. The EMR-MSM methodology is first applied to a conceptual, nonlinear, stochastic climate model of coupled slow and fast variables, in which only slow variables are observed. It is shown that the resulting closure model with energy-conserving nonlinearities efficiently captures the main statistical features of the slow variables, even when there is no formal scale separation and the fast variables are quite energetic. Second, an MSM is shown to successfully reproduce the statistics of a partially observed, generalized Lotka-Volterra model of population dynamics in its chaotic regime. The challenges here include the rarity of strange attractors in the model's parameter
Mathaes, Roman; Mahler, Hanns-Christian; Vorgrimler, Lothar; Steinberg, Henrik; Dreher, Sascha; Roggo, Yves; Nieto, Alejandra; Brown, Helen; Roehl, Holger; Adler, Michael; Luemkemann, Joerg; Huwyler, Joerg; Lam, Philippe; Stauch, Oliver; Mohl, Silke; Streubel, Alexander
2016-01-01
The majority of parenteral drug products are manufactured in glass vials with an elastomeric rubber stopper and a crimp cap. The vial sealing process is a critical process step during fill-and-finish operations, as it defines the seal quality of the final product. Different critical capping process parameters can affect rubber stopper defects, rubber stopper compression, container closure integrity, and also crimp cap quality. A sufficiently high force to remove the flip-off button prior to usage is required to ensure quality of the drug product unit by the flip-off button during storage, transportation, and until opening and use. Therefore, the final product is 100% visually inspected for lose or defective crimp caps, which is subjective as well as time- and labor-intensive. In this study, we sealed several container closure system configurations with different capping equipment settings (with corresponding residual seal force values) to investigate the torque moment required to turn the crimp cap. A correlation between torque moment and residual seal force has been established. The torque moment was found to be influenced by several parameters, including diameter of the vial head, type of rubber stopper (serum or lyophilized) and type of crimp cap (West(®) or Datwyler(®)). In addition, we measured the force required to remove the flip-off button of a sealed container closure system. The capping process had no influence on measured forces; however, it was possible to detect partially crimped vials. In conclusion, a controlled capping process with a defined target residual seal force range leads to a tight crimp cap on a sealed container closure system and can ensure product quality. The majority of parenteral drug products are manufactured in a glass vials with an elastomeric rubber stopper and a crimp cap. The vial sealing process is a critical process step during fill-and-finish operations, as it defines the seal quality of the final product. An adequate force
Closure plan for the M-Area settling basin and vicinity at the Savannah River Plant
International Nuclear Information System (INIS)
Colven, W.P.; Pickett, J.B.; Muska, C.F.; Boone, L.F.
1988-03-01
The closure plan for the M-Area settling basin and vicinity was originally submitted to the South Carolina Department of Health and Environmental Control (SCDHEC) Bureau of Solid and Hazardous Waste Management in September 1984. The plan was revised in July and November 1985 in response to SCDHEC comments. After public comment in April through July 1986, the closure plan was conditionally approved by SCDHEC in March 1987. The conditions included (1) providing a temporary wastewater treatment facility to process the water remaining in the basin, (2) using a burn box to limit ash emissions from burning in the basin, (3) obtaining SCDHEC approval prior to operating the leach field, and (4) completing all closure activities within three years of the startup date
MOMENTS OF THE LENGTH OF LINE SEGMENTS IN HOMOGENEOUS PLANAR STIT TESSELLATIONS
Directory of Open Access Journals (Sweden)
Christoph Thäle
2011-05-01
Full Text Available Homogeneous planar tessellations stable under iteration (STIT tessellations are considered. Using recent results about the joint distribution of direction and length of the typical I-, K- and J-segment we prove closed formulas for the first, second and higher moments of the length of these segments given their direction. This especially leads to themean values and variances of these quantities andmean value relations as well as general moment relationships. Moreover, the relation between these mean values and certain conditional mean values (and also higher moments is discussed. The results are also illustrated for several examples.
Biological constraints do not entail cognitive closure.
Vlerick, Michael
2014-12-01
From the premise that our biology imposes cognitive constraints on our epistemic activities, a series of prominent authors--most notably Fodor, Chomsky and McGinn--have argued that we are cognitively closed to certain aspects and properties of the world. Cognitive constraints, they argue, entail cognitive closure. I argue that this is not the case. More precisely, I detect two unwarranted conflations at the core of arguments deriving closure from constraints. The first is a conflation of what I will refer to as 'representation' and 'object of representation'. The second confuses the cognitive scope of the assisted mind for that of the unassisted mind. Cognitive closure, I conclude, cannot be established from pointing out the (uncontroversial) existence of cognitive constraints. Copyright © 2014 Elsevier Ltd. All rights reserved.
Hanford Patrol Academy demolition sites closure plan
Energy Technology Data Exchange (ETDEWEB)
1993-09-30
The Hanford Site is owned by the U.S. Government and operated by the U.S. Department of Energy, Richland Operations Office. Westinghouse Hanford Company is a major contractor to the U.S. Department of Energy, Richland Operations Office and serves as co-operator of the Hanford Patrol Academy Demolition Sites, the unit addressed in this paper. This document consists of a Hanford Facility Dangerous Waste Part A Permit Application, Form 3 (Revision 4), and a closure plan for the site. An explanation of the Part A Form 3 submitted with this closure plan is provided at the beginning of the Part A section. This Hanford Patrol Academy Demolition Sites Closure Plan submittal contains information current as of December 15, 1994.
Development of an arid site closure plan
International Nuclear Information System (INIS)
Nyhan, J.W.; Barnes, F.J.
1987-01-01
This document describes the development of a prototype plan for the effective closure and stabilization of an arid low-level waste disposal site. This plan will provide demonstrated closure techniques for a trench in a disposal site at Los Alamos. The accuracy of modeling soil water storage by two hydrologic models, CREAMS and HELP, was tested by comparing simulation results with field measurements of soil moisture in eight experimental landfill cover systems having a range of well-defined soil profiles and vegetative covers. Regression analysis showed that CREAMS generally represented soil moisture more accurately than HELP simulations. Precautions for determining parameter values for model input and for interpreting simulation results are discussed. A specific example is presented showing how the field-validated hydrologic models can be used to develop a final prototype closure plan. 15 refs., 13 figs., 3 tabs
Primary closure of equine laryngotomy incisions
DEFF Research Database (Denmark)
Lindegaard, C.; Karlsson, L.; Ekstrøm, Claus Thorn
2016-01-01
incision between January 1995 and June 2012 were reviewed. Horses with a laryngotomy incision closed in three layers for primary healing were included. Descriptive data on healing characteristics and complications of laryngotomy wounds were collected from the medical records and via follow......The objective was to report healing characteristics and complications after primary closure of equine laryngotomies and analyse factors potentially associated with complications. This retrospective case series of the medical records of horses (n = 180) undergoing laryngoplasty and laryngotomy...... after primary closure of equine laryngotomy incisions are infrequent and considered of minimal severity and can be performed safely when paying careful attention to the closure of the cricothyroid membrane....
Consistent calculation of the polarization electric dipole moment by the shell-correction method
International Nuclear Information System (INIS)
Denisov, V.Yu.
1992-01-01
Macroscopic calculations of the polarization electric dipole moment which arises in nuclei with an octupole deformation are discussed in detail. This dipole moment is shown to depend on the position of the center of gravity. The conditions of consistency of the radii of the proton and neutron potentials and the radii of the proton and neutron surfaces, respectively, are discussed. These conditions must be incorporated in a shell-correction calculation of this dipole moment. A correct calculation of this moment by the shell-correction method is carried out. Dipole transitions between (on the one hand) levels belonging to an octupole vibrational band and (on the other) the ground state in rare-earth nuclei with a large quadrupole deformation are studied. 19 refs., 3 figs
Hamiltonian closures in fluid models for plasmas
Tassi, Emanuele
2017-11-01
This article reviews recent activity on the Hamiltonian formulation of fluid models for plasmas in the non-dissipative limit, with emphasis on the relations between the fluid closures adopted for the different models and the Hamiltonian structures. The review focuses on results obtained during the last decade, but a few classical results are also described, in order to illustrate connections with the most recent developments. With the hope of making the review accessible not only to specialists in the field, an introduction to the mathematical tools applied in the Hamiltonian formalism for continuum models is provided. Subsequently, we review the Hamiltonian formulation of models based on the magnetohydrodynamics description, including those based on the adiabatic and double adiabatic closure. It is shown how Dirac's theory of constrained Hamiltonian systems can be applied to impose the incompressibility closure on a magnetohydrodynamic model and how an extended version of barotropic magnetohydrodynamics, accounting for two-fluid effects, is amenable to a Hamiltonian formulation. Hamiltonian reduced fluid models, valid in the presence of a strong magnetic field, are also reviewed. In particular, reduced magnetohydrodynamics and models assuming cold ions and different closures for the electron fluid are discussed. Hamiltonian models relaxing the cold-ion assumption are then introduced. These include models where finite Larmor radius effects are added by means of the gyromap technique, and gyrofluid models. Numerical simulations of Hamiltonian reduced fluid models investigating the phenomenon of magnetic reconnection are illustrated. The last part of the review concerns recent results based on the derivation of closures preserving a Hamiltonian structure, based on the Hamiltonian structure of parent kinetic models. Identification of such closures for fluid models derived from kinetic systems based on the Vlasov and drift-kinetic equations are presented, and
A kinematic view of loop closure.
Coutsias, Evangelos A; Seok, Chaok; Jacobson, Matthew P; Dill, Ken A
2004-03-01
We consider the problem of loop closure, i.e., of finding the ensemble of possible backbone structures of a chain segment of a protein molecule that is geometrically consistent with preceding and following parts of the chain whose structures are given. We reduce this problem of determining the loop conformations of six torsions to finding the real roots of a 16th degree polynomial in one variable, based on the robotics literature on the kinematics of the equivalent rotator linkage in the most general case of oblique rotators. We provide a simple intuitive view and derivation of the polynomial for the case in which each of the three pair of torsional axes has a common point. Our method generalizes previous work on analytical loop closure in that the torsion angles need not be consecutive, and any rigid intervening segments are allowed between the free torsions. Our approach also allows for a small degree of flexibility in the bond angles and the peptide torsion angles; this substantially enlarges the space of solvable configurations as is demonstrated by an application of the method to the modeling of cyclic pentapeptides. We give further applications to two important problems. First, we show that this analytical loop closure algorithm can be efficiently combined with an existing loop-construction algorithm to sample loops longer than three residues. Second, we show that Monte Carlo minimization is made severalfold more efficient by employing the local moves generated by the loop closure algorithm, when applied to the global minimization of an eight-residue loop. Our loop closure algorithm is freely available at http://dillgroup. ucsf.edu/loop_closure/. Copyright 2004 Wiley Periodicals, Inc. J Comput Chem 25: 510-528, 2004
Modeling elephant-mediated cascading effects of water point closure.
Hilbers, Jelle P; Van Langevelde, Frank; Prins, Herbert H T; Grant, C C; Peel, Mike J S; Coughenour, Michael B; De Knegt, Henrik J; Slotow, Rob; Smit, Izak P J; Kiker, Greg A; De Boer, Willem F
2015-03-01
Wildlife management to reduce the impact of wildlife on their habitat can be done in several ways, among which removing animals (by either culling or translocation) is most often used. There are, however, alternative ways to control wildlife densities, such as opening or closing water points. The effects of these alternatives are poorly studied. In this paper, we focus on manipulating large herbivores through the closure of water points (WPs). Removal of artificial WPs has been suggested in order to change the distribution of African elephants, which occur in high densities in national parks in Southern Africa and are thought to have a destructive effect on the vegetation. Here, we modeled the long-term effects of different scenarios of WP closure on the spatial distribution of elephants, and consequential effects on the vegetation and other herbivores in Kruger National Park, South Africa. Using a dynamic ecosystem model, SAVANNA, scenarios were evaluated that varied in availability of artificial WPs; levels of natural water; and elephant densities. Our modeling results showed that elephants can indirectly negatively affect the distributions of meso-mixed feeders, meso-browsers, and some meso-grazers under wet conditions. The closure of artificial WPs hardly had any effect during these natural wet conditions. Under dry conditions, the spatial distribution of both elephant bulls and cows changed when the availability of artificial water was severely reduced in the model. These changes in spatial distribution triggered changes in the spatial availability of woody biomass over the simulation period of 80 years, and this led to changes in the rest of the herbivore community, resulting in increased densities of all herbivores, except for giraffe and steenbok, in areas close to rivers. The spatial distributions of elephant bulls and cows showed to be less affected by the closure of WPs than most of the other herbivore species. Our study contributes to ecologically
Reactor vessel closure head replacements in 1997
International Nuclear Information System (INIS)
Anon.
1997-01-01
The Framatome-Jeumont Industrie consortium have completed in 1997 28 reactor vessel (RV) closure head replacements, including five on 1300 MWe class PWR units. Framatome manages the operations and handles removal and reinstallation of equipment (not including the control rod drive mechanisms (CRDM)) and the requalification tests, while JI, which manufactures the CRDMs, is involved in the CRDM cutting, re-machining and welding operations, using tools of original design, in order to optimize the RV closure head operation in terms of costs, schedule and dosage
Closure properties of Watson-Crick grammars
Zulkufli, Nurul Liyana binti Mohamad; Turaev, Sherzod; Tamrin, Mohd Izzuddin Mohd; Azeddine, Messikh
2015-12-01
In this paper, we define Watson-Crick context-free grammars, as an extension of Watson-Crick regular grammars and Watson-Crick linear grammars with context-free grammar rules. We show the relation of Watson-Crick (regular and linear) grammars to the sticker systems, and study some of the important closure properties of the Watson-Crick grammars. We establish that the Watson-Crick regular grammars are closed under almost all of the main closure operations, while the differences between other Watson-Crick grammars with their corresponding Chomsky grammars depend on the computational power of the Watson-Crick grammars which still need to be studied.
Straight line closure of congenital macrostomia
Directory of Open Access Journals (Sweden)
Schwarz Richard
2004-01-01
Full Text Available The results of patients operated on by Nepal Cleft Lip and Palate Association (NECLAPA surgeons for congenital macrostomia were prospectively studied between January 2000 and December 2002. There were four males and three females with a median age of 10 years. Three had an associated branchial arch syndrome. In all patients an overlapping repair of orbicularis oris was done. Six patients had a straight line closure with excellent cosmetic results and one a Z-plasty with a more obvious scar. All had a normal appearing commissure. Overlapping orbicularis repair with straight line skin closure for this rare congenital anomaly is recommended.
Environmental considerations in mine closure planning
International Nuclear Information System (INIS)
Ricks, G.
1997-01-01
Mine closure planning considers the best ways to plan and manage the environmental changes and socio-economic effects associated with the closing of mines. While the criteria for judging successful closures may vary, it is particularly important for physical, chemical and biological stability to be achieved and for final land use to be appropriate. Trust funds are increasingly favoured as a practical means of fulfilling the requirement for a financial surety and of ensuring that financial provision is available at the end of the mine's life. (author)
Uncertainty Quantification of Multi-Phase Closures
Energy Technology Data Exchange (ETDEWEB)
Nadiga, Balasubramanya T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baglietto, Emilio [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
2017-10-27
In the ensemble-averaged dispersed phase formulation used for CFD of multiphase ows in nuclear reactor thermohydraulics, closures of interphase transfer of mass, momentum, and energy constitute, by far, the biggest source of error and uncertainty. Reliable estimators of this source of error and uncertainty are currently non-existent. Here, we report on how modern Validation and Uncertainty Quanti cation (VUQ) techniques can be leveraged to not only quantify such errors and uncertainties, but also to uncover (unintended) interactions between closures of di erent phenomena. As such this approach serves as a valuable aide in the research and development of multiphase closures. The joint modeling of lift, drag, wall lubrication, and turbulent dispersion|forces that lead to tranfer of momentum between the liquid and gas phases|is examined in the frame- work of validation of the adiabatic but turbulent experiments of Liu and Banko , 1993. An extensive calibration study is undertaken with a popular combination of closure relations and the popular k-ϵ turbulence model in a Bayesian framework. When a wide range of super cial liquid and gas velocities and void fractions is considered, it is found that this set of closures can be validated against the experimental data only by allowing large variations in the coe cients associated with the closures. We argue that such an extent of variation is a measure of uncertainty induced by the chosen set of closures. We also nd that while mean uid velocity and void fraction pro les are properly t, uctuating uid velocity may or may not be properly t. This aspect needs to be investigated further. The popular set of closures considered contains ad-hoc components and are undesirable from a predictive modeling point of view. Consequently, we next consider improvements that are being developed by the MIT group under CASL and which remove the ad-hoc elements. We use non-intrusive methodologies for sensitivity analysis and calibration (using
Laser peripheral iridoplasty for angle-closure.
Ng, Wai Siene; Ang, Ghee Soon; Azuara-Blanco, Augusto
2012-02-15
Angle-closure glaucoma is a leading cause of irreversible blindness in the world. Treatment is aimed at opening the anterior chamber angle and lowering the IOP with medical and/or surgical treatment (e.g. trabeculectomy, lens extraction). Laser iridotomy works by eliminating pupillary block and widens the anterior chamber angle in the majority of patients. When laser iridotomy fails to open the anterior chamber angle, laser iridoplasty may be recommended as one of the options in current standard treatment for angle-closure. Laser peripheral iridoplasty works by shrinking and pulling the peripheral iris tissue away from the trabecular meshwork. Laser peripheral iridoplasty can be used for crisis of acute angle-closure and also in non-acute situations. To assess the effectiveness of laser peripheral iridoplasty in the treatment of narrow angles (i.e. primary angle-closure suspect), primary angle-closure (PAC) or primary angle-closure glaucoma (PACG) in non-acute situations when compared with any other intervention. In this review, angle-closure will refer to patients with narrow angles (PACs), PAC and PACG. We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2011, Issue 12), MEDLINE (January 1950 to January 2012), EMBASE (January 1980 to January 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 5 January 2012. We included only randomised controlled trials (RCTs) in this review. Patients with narrow angles, PAC or PACG were eligible. We excluded studies that included only patients with acute presentations
Special closure for radioactive shipping container
International Nuclear Information System (INIS)
Otts, J.V.
1976-03-01
The objective of this program was to develop a special lid closure for radioactive material shipping containers, typically steel drums. Three closure techniques were designed, fabricated, and proven to be structurally adequate to protect 1000 lb when dropped 30 ft. The three designs were (1) a 6-in. lid extension (skirt), (2) a 6-in. inner lid, and (3) c-clamps used at the container/lid interface. Based upon structural integrity, economic impact, and minimal design change, the 6-in. lid extension is recommended
Multidisciplinary Assessment in Optimising Results of Percutaneous Patent Foramen Ovale Closure.
Davies, Allan; Ekmejian, Avedis; Collins, Nicholas; Bhagwandeen, Rohan
2017-03-01
Percutaneous patent foramen ovale (PFO) closure is a therapeutic option to prevent recurrent cerebral ischaemia in patients with cryptogenic stroke and transient cerebral ischaemia (TIA). The apparent lack of benefit seen in previous randomised trials has, in part, reflected inclusion of patients with alternate mechanisms of stroke. The role of formal neurology involvement in accurately delineating the likely aetiology of stroke or TIA is crucial in appropriate identification of patients for device closure. Furthermore, as the benefits of device closure may accrue over time, long-term follow-up is essential to define the role of device closure in management of presumed cryptogenic stroke. We retrospectively reviewed our experience with percutaneous PFO device closure since 2005. All subjects who underwent PFO closure at John Hunter and Lake Macquarie Private Hospitals were included in the study. All patients referred for device closure following cryptogenic stroke or TIA had first undergone formal neurology review with appropriate imaging and exclusion of paroxysmal atrial arrhythmia. Patients with a history of transient ischaemic attack (TIA) are frequently referred to a specialised clinic, aimed to identify patients with conditions not referable to cerebral ischaemia, with investigations initiated by the specialist clinic to elucidate an underlying aetiology. Outcome data was derived from the Hunter New England Area Local Health District Cardiac and Stroke Outcomes Unit, in addition to review of the medical record. The Cardiac and Stroke Outcomes Unit prospectively identified all patients presenting with stroke, TIA and atrial fibrillation. One hundred and twelve consecutive patients undergoing percutaneous patent foramen ovale closure between 2005 and 2015 were identified. The average age was 42.7 years and 57 (50.9%) patients were male. Cryptogenic stroke (68.8%) and transient cerebral ischaemia (23.2%) were the most common indications for PFO closure, with the
Measurement of the electric dipole moment and magnetic moment anomaly of the muon
Onderwater, CJG
2005-01-01
The experimental precision of the anomalous magnetic moment of the muon has been improved to 0.5 part-per-million by the Brookhaven E821 experiment, similar to the theoretical uncertainty. In the same experiment, a new limit on the electric dipole moment of 2.8 x 10(-19) e-cm (95% CL) was set. The
An online database of nuclear electromagnetic moments
International Nuclear Information System (INIS)
Mertzimekis, T.J.; Stamou, K.; Psaltis, A.
2016-01-01
Measurements of nuclear magnetic dipole and electric quadrupole moments are considered quite important for the understanding of nuclear structure both near and far from the valley of stability. The recent advent of radioactive beams has resulted in a plethora of new, continuously flowing, experimental data on nuclear structure – including nuclear moments – which hinders the information management. A new, dedicated, public and user friendly online database ( (http://magneticmoments.info)) has been created comprising experimental data of nuclear electromagnetic moments. The present database supersedes existing printed compilations, including also non-evaluated series of data and relevant meta-data, while putting strong emphasis on bimonthly updates. The scope, features and extensions of the database are reported.
Pengenalan Pose Tangan Menggunakan HuMoment
Directory of Open Access Journals (Sweden)
Dina Budhi Utami
2017-02-01
Full Text Available Computer vision yang didasarkan pada pengenalan bentuk memiliki banyak potensi dalam interaksi manusia dan komputer. Pose tangan dapat dijadikan simbol interaksi manusia dengan komputer seperti halnya pada penggunaan berbagai pose tangan pada bahasa isyarat. Berbagai pose tangan dapat digunakan untuk menggantikan fungsi mouse, untuk mengendalikan robot, dan sebagainya. Penelitian ini difokuskan pada pembangunan sistem pengenalan pose tangan menggunakan HuMoment. Proses pengenalan pose tangan dimulai dengan melakukan segmentasi citra masukan untuk menghasilkan citra ROI (Region of Interest yaitu area telapak tangan. Selanjutnya dilakukan proses deteksi tepi. Kemudian dilakukan ekstraksi nilai HuMoment. Nilai HuMoment dikuantisasikan ke dalam bukukode yang dihasilkan dari proses pelatihan menggunakan K-Means. Proses kuantisasi dilakukan dengan menghitung nilai Euclidean Distance terkecil antara nilai HuMomment citra masukan dan bukukode. Berdasarkan hasil penelitian, nilai akurasi sistem dalam mengenali pose tangan adalah 88.57%.
The vector meson with anomalous magnetic moment
International Nuclear Information System (INIS)
Boyarkin, O.M.
1976-01-01
The possibility of introducing an anomalous magnetic moment into the Stuckelberg version of the charged vector meson theory is considered. It is shown that the interference of states with spins equal to one and zero is absent in the presence of an anomalous magnetic moment of a particle. The differential cross section of scattering on the Coulomb field of a nucleus is calculated, and so are the differential and integral cross sections of meson pair production on annihilation of two gamma quanta. The two-photon mechanism of production of a meson pair in colliding electron-positron beams is considered. It is shown that with any value of the anomalous magnetic moment the cross section of the esup(+)esup(-) → esup(+)esup(-)γsup(*)γsup(*) → esup(+)esup(-)Wsup(+)Wsup(-) reaction exceeds that of the esup(+)esup(-) → γsup(*) → Wsup(+)Wsup(-) at sufficiently high energies
The anomalous magnetic moment of the muon
Jegerlehner, Friedrich
2017-01-01
This research monograph covers extensively the theory of the muon anomalous magnetic moment and provides estimates of the theoretical uncertainties. The muon anomalous magnetic moment is one of the most precisely measured quantities in elementary particle physics and provides one of the most stringent tests of relativistic quantum field theory as a fundamental theoretical framework. It allows for an extremely precise check of the standard model of elementary particles and of its limitations. This book reviews the present state of knowledge of the anomalous magnetic moment a=(g-2)/2 of the muon. Recent experiments at the Brookhaven National Laboratory now reach the unbelievable precision of 0.5 parts per million, improving the accuracy of previous g-2 experiments at CERN by a factor of 14. In addition, quantum electrodynamics and electroweak and hadronic effects are reviewed. Since non-perturbative hadronic effects play a key role for the precision test, their evaluation is described in detail. Perspectives fo...
A corrector for spacecraft calculated electron moments
Directory of Open Access Journals (Sweden)
J. Geach
2005-03-01
Full Text Available We present the application of a numerical method to correct electron moments calculated on-board spacecraft from the effects of potential broadening and energy range truncation. Assuming a shape for the natural distribution of the ambient plasma and employing the scalar approximation, the on-board moments can be represented as non-linear integral functions of the underlying distribution. We have implemented an algorithm which inverts this system successfully over a wide range of parameters for an assumed underlying drifting Maxwellian distribution. The outputs of the solver are the corrected electron plasma temperature Te, density Ne and velocity vector Ve. We also make an estimation of the temperature anisotropy A of the distribution. We present corrected moment data from Cluster's PEACE experiment for a range of plasma environments and make comparisons with electron and ion data from other Cluster instruments, as well as the equivalent ground-based calculations using full 3-D distribution PEACE telemetry.
Composite quarks and their magnetic moments
International Nuclear Information System (INIS)
Parthasarathy, R.
1980-08-01
A composite quark model based on the symmetry group SU(10)sub(flavour) x SU(10)sub(colour) with the assumption of mass non-degenerate sub-quarks is considered. Magnetic moments of quarks and sub-quarks are obtained from the observed nucleon magnetic moments. Using these quark and sub-quark magnetic moments, a satisfactory agreement for the radiative decays of vector mesons (rho,ω) is obtained. The ratio of the masses of the sub-quarks constituting the u,d,s quarks are found to be Msub(p)/Msub(n) = 0.3953 and Msub(p)/Msub(lambda) = 0.596, indicating a mass hierarchy Msub(p) < Msub(n) < Msub(lambda) for the sub-quarks. (author)
Kπ=0+ band moment of inertia anomaly
International Nuclear Information System (INIS)
Zeng, J.Y.; Wu, C.S.; Cheng, L.; Lin, C.Z.; China Center of Advanced Science and Technology
1990-01-01
The moments of inertia of K π =0 + bands in the well-deformed nuclei are calculated by a particle-number-conserving treatment for the cranked shell model. The very accurate solutions to the low-lying K π =0 + bands are obtained by making use of an effective K truncation. Calculations show that the main contribution to the moments of inertia comes from the nucleons in the intruding high-j orbits. Considering the fact that no free parameter is involved in the calculation and no extra inert core contribution is added, the agreement between the calculated and the observed moments of inertia of 0 + bands in 168 Er is very satisfactory
Baryon magnetic moments: Symmetries and relations
Energy Technology Data Exchange (ETDEWEB)
Parreno, Assumpta [University of Barcelona; Savage, Martin [Univ. of Washington, Seattle, WA (United States); Tiburzi, Brian [City College of New York, NY (United States); City Univ. (CUNY), NY (United States); Wilhelm, Jonas [Justus-Liebig-Universitat Giessen, Giessen, Germany; Univ. of Washington, Seattle, WA (United States); Chang, Emmanuel [Univ. of Washington, Seattle, WA (United States); Detmold, William [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Orginos, Kostas [College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2018-04-01
Magnetic moments of the octet baryons are computed using lattice QCD in background magnetic fields, including the first treatment of the magnetically coupled Σ0- Λ system. Although the computations are performed for relatively large values of the up and down quark masses, we gain new insight into the symmetries and relations between magnetic moments by working at a three-flavor mass-symmetric point. While the spinflavor symmetry in the large Nc limit of QCD is shared by the naïve constituent quark model, we find instances where quark model predictions are considerably favored over those emerging in the large Nc limit. We suggest further calculations that would shed light on the curious patterns of baryon magnetic moments.
Neutron Electric Dipole Moment from colored scalars⋆
Directory of Open Access Journals (Sweden)
Fajfer Svjetlana
2014-01-01
Full Text Available We present new contributions to the neutron electric dipole moment induced by a color octet, weak doublet scalar, accommodated within a modified Minimal Flavor Violating framework. These flavor non-diagonal couplings of the color octet scalar might account for an assymmetry of order 3 × 10−3 for aCP(D0 → K−K+ − aCP(D0 → π+π− at tree level. The same couplings constrained by this assymmetry also induce two-loop contributions to the neutron electric dipole moment. We find that the direct CP violating asymmetry in neutral D-meson decays is more constraining on the allowed parameter space than the current experimental bound on neutron electric dipole moment.
Energy Technology Data Exchange (ETDEWEB)
Ohtsubo, T., E-mail: tohtsubo@np.gs.niigata-u.ac.jp; Kawamura, Y.; Ohya, S. [Niigata University, Department of Physics (Japan); Izumikawa, T. [Niigata University, Radioisotope Center (Japan); Nishimura, K. [Toyama University, Faculty of Engineering (Japan); Muto, S. [Neutron Science Laboratory, KEK (Japan); Shinozuka, T. [Tohoku University, Cyclotron and Radioisotope Center (Japan)
2007-11-15
Nuclear magnetic resonances were measured for {sup 48}Sc and {sup 44m}Sc oriented at 8 mK in an Fe host metal. The magnetic hyperfine splitting frequencies at an external magnetic field of 0.2 T were determined to be 63.22(11) MHz and 64.81(1) MHz for {sup 48}Sc and {sup 44m}Sc, respectively. With the known magnetic moment of {mu}({sup 44m}Sc)=+3.88 (1) {mu}{sub N}, the magnetic moment of {sup 48}Sc is deduced as {mu}({sup 44}Sc)=+3.785(12) {mu}{sub N}. The measured magnetic moment of {sup 48}Sc is discussed in terms of the shell model using the effective interactions.
Closure Strategy Nevada Test Site Area 5 Radioactive Waste Management Site
Energy Technology Data Exchange (ETDEWEB)
NSTec Environmental Management
2007-03-01
This paper presents an overview of the strategy for closure of part of the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada Test Site (NTS), which is about 65 miles northwest of Las Vegas, Nevada (Figure 1). The Area 5 RWMS is in the northern part of Frenchman Flat, approximately 14 miles north of Mercury. The Area 5 RWMS encompasses 732 acres subdivided into quadrants, and is bounded by a 1,000-foot (ft)-wide buffer zone. The northwest and southwest quadrants have not been developed. The northeast and southeast quadrants have been used for disposal of unclassified low-level radioactive waste (LLW) and indefinite storage of classified materials. This paper focuses on closure of the 38 waste disposal and classified material storage units within the southeast quadrant of the Area 5 RWMS, called the ''92-Acre Area''. The U.S Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO) is currently planning to close the 92-Acre Area by 2011. Closure planning for this site must take into account the regulatory requirements for a diversity of waste streams, disposal and storage configurations, disposal history, and site conditions. For ease of discussion, the 92-Acre Area has been subdivided into six closure units defined by waste type, location, and similarity in regulatory requirements. Each of the closure units contains one or more waste disposal units; waste disposal units are also called waste disposal cells. The paper provides a brief background of the Area 5 RWMS, identifies key closure issues for the 92-Acre Area, recommends actions to address the issues, and provides the National Security Technologies, LLC (NSTec), schedule for closure.
Energy Technology Data Exchange (ETDEWEB)
Xu, Kuan-Man [NASA Langley Research Center, Hampton, VA (United States); Cheng, Anning [NASA Langley Research Center, Hampton, VA (United States); Science Systems and Applications, Inc., Hampton, VA (United States)
2015-11-24
The intermediately-prognostic higher-order turbulence closure (IPHOC) introduces a joint double-Gaussian distribution of liquid water potential temperature (θ_{l} ), total water mixing ratio (q_{t}), and vertical velocity (w) to represent any skewed turbulence circulation. The distribution is inferred from the first-, second-, and third-order moments of the variables given above, and is used to diagnose cloud fraction and gridmean liquid water mixing ratio, as well as the buoyancy term and fourth-order terms in the equations describing the evolution of the second- and third-order moments. Only three third-order moments, i.e., the triple moments of θ_{l}, q_{t}, and w, are predicted in IPHOC.
Determination of the neutron magnetic moment
International Nuclear Information System (INIS)
Greene, G.L.; Ramsey, N.F.; Mampe, W.; Pendlebury, J.M.; Smith, K.; Dress, W.B.; Miller, P.D.; Perrin, P.
1981-01-01
The neutron magnetic moment has been measured with an improvement of a factor of 100 over the previous best measurement. Using a magnetic resonance spectrometer of the separated oscillatory field type capable of determining a resonance signal for both neutrons and protons (in flowing H 2 O), we find μ/sub n//μ/sub p/ = 0.68497935(17) (0.25 ppM). The neutron magnetic moment can also be expressed without loss of accuracy in a variety of other units
Macroscopic quantum tunneling of the magnetic moment
Tejada, J.; Hernandez, J. M.; del Barco, E.
1999-05-01
In this paper we review the work done on magnetic relaxation during the last 10 years on both single-domain particles and magnetic molecules and its contribution to the discovery of quantum tunneling of the magnetic moment (Chudnovsky and Tejada, Macroscopic Quantum tunneling of the Magnetic moment, Cambridge University press, Cambridge, 1998). We present first the theoretical expressions and their connection to quantum relaxation and secondly, we show and discuss the experimental results. Finally, we discuss very recent hysteresis data on Mn 12Ac molecules at extremely large sweeping rate for the external magnetic field which suggest the existence of quantum spin—phonon avalanches.
The Method of Moments in electromagnetics
Gibson, Walton C
2014-01-01
Now Covers Dielectric Materials in Practical Electromagnetic DevicesThe Method of Moments in Electromagnetics, Second Edition explains the solution of electromagnetic integral equations via the method of moments (MOM). While the first edition exclusively focused on integral equations for conducting problems, this edition extends the integral equation framework to treat objects having conducting as well as dielectric parts.New to the Second EditionExpanded treatment of coupled surface integral equations for conducting and composite conducting/dielectric objects, including objects having multipl
Hyperon magnetic moments and total cross sections
International Nuclear Information System (INIS)
Lipkin, H.J.
1982-06-01
The new data on both total cross sections and magnetic moments are simply described by beginning with the additive quark model in an SU(3) limit where all quarks behave like strange quarks and breaking both additivity and SU(3) simultaneously with an additional non-additive mechanism which affects only nonstrange quark contributions. The suggestion that strange quarks behave more simply than nonstrange may provide clues to underlying structure or dynamics. Small discrepancies in the moments are analyzed and shown to provide serious difficulties for most models if they are statistically significant. (author)
Scale invariants from Gaussian-Hermite moments
Czech Academy of Sciences Publication Activity Database
Yang, B.; Kostková, Jitka; Flusser, Jan; Suk, Tomáš
2017-01-01
Roč. 132, č. 1 (2017), s. 77-84 ISSN 0165-1684 R&D Projects: GA ČR GA15-16928S Institutional support: RVO:67985556 Keywords : Scale invariants * Gaussian–Hermite moments * Variable modulation * Normalization * Zernike moments Subject RIV: JD - Computer Applications, Robotics OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 3.110, year: 2016 http://library.utia.cas.cz/separaty/2016/ZOI/flusser-0466031.pdf
Spin and orbital moments in actinide compounds
DEFF Research Database (Denmark)
Lebech, B.; Wulff, M.; Lander, G.H.
1991-01-01
The extended spatial distribution of both the transition-metal 3d electrons and the actinide 5f electrons results in a strong interaction between these electron states when the relevant elements are alloyed. A particular interesting feature of this hybridization, which is predicted by single...... experiments designed to determine the magnetic moments at the actinide and transition-metal sublattice sites in compounds such as UFe2, NpCo2, and PuFe2 and to separate the spin and orbital components at the actinide sites. The results show, indeed, that the ratio of the orbital to spin moment is reduced...
Moments of structure functions in full QCD
International Nuclear Information System (INIS)
Dolgov, D.; Brower, R.; Capitani, S.; Negele, J.W.; Pochinsky, A.; Renner, D.; Eicker, N.; Lippert, T.; Schilling, K.; Edwards, R.G.; Heller, U.M.
2001-01-01
Moments of the quark density distribution, moments of the quark helicity distribution, and the tensor charge are calculated in full QCD. Calculations of matrix elements of operators from the operator product expansion have been performed on 16 3 x 32 lattices for Wilson fermions at β = 5.6 using configurations from the SESAM collaboration and at β = 5.5 using configurations from SCRI. One-loop perturbative renormalization corrections are included. Selected results are compared with corresponding quenched calculations and with calculations using cooled configurations
Nuclear moments of inertia at high spin
International Nuclear Information System (INIS)
Deleplanque, M.A.
1982-10-01
The competition between collective motion and alignment at high spin can be evaluated by measuring two complementary dynamic moments of inertia. The first, I band, measured in γ-γ correlation experiments, relates to the collective properties of the nucleus. A new moment of inertia I/sub eff/ is defined here, which contains both collective and alignment effects. Both of these can be measured in continuum γ-ray spectra of rotational nuclei up to high frequencies. The evolution of γ-ray spectra for Er nuclei from mass 160 to 154 shows that shell effects can directly be observed in the spectra of the lighter nuclei
The maximum entropy method of moments and Bayesian probability theory
Bretthorst, G. Larry
2013-08-01
The problem of density estimation occurs in many disciplines. For example, in MRI it is often necessary to classify the types of tissues in an image. To perform this classification one must first identify the characteristics of the tissues to be classified. These characteristics might be the intensity of a T1 weighted image and in MRI many other types of characteristic weightings (classifiers) may be generated. In a given tissue type there is no single intensity that characterizes the tissue, rather there is a distribution of intensities. Often this distributions can be characterized by a Gaussian, but just as often it is much more complicated. Either way, estimating the distribution of intensities is an inference problem. In the case of a Gaussian distribution, one must estimate the mean and standard deviation. However, in the Non-Gaussian case the shape of the density function itself must be inferred. Three common techniques for estimating density functions are binned histograms [1, 2], kernel density estimation [3, 4], and the maximum entropy method of moments [5, 6]. In the introduction, the maximum entropy method of moments will be reviewed. Some of its problems and conditions under which it fails will be discussed. Then in later sections, the functional form of the maximum entropy method of moments probability distribution will be incorporated into Bayesian probability theory. It will be shown that Bayesian probability theory solves all of the problems with the maximum entropy method of moments. One gets posterior probabilities for the Lagrange multipliers, and, finally, one can put error bars on the resulting estimated density function.
Charged point particles with magnetic moment in general relativity
International Nuclear Information System (INIS)
Amorim, R.; Tiomno, J.
1977-01-01
Halbwachs Lagrangean formalism for the theory of charged point particles with spin (g = 2) is generalized and formulated in General Relativity for particles of arbitrary charge and magnetic moment. Equations are obtained, both corresponding to Frenkel's condition Ssub(μν)Xsup(ν) = 0 and to Nakano's condition Ssub(μν)Psup(ν) = 0. With the later condition the exact equations are highly coupled and non linear. When linearized in the electromagnetic and gravitational fields they coincide with de Groot-Suttorp equations for vanishing gravitational fields and with Dixon-Wald equations in the absence of electromagnetic field. The equations corresponding to Frenkel's condition, when linearized in Ssub(μν), coincide with Papapetrou's and Frenkel's equations in the corresponding limits [pt
Parents' Attitudes to the Closure of Small Rural Primary Schools
Archbold, A.; Nisbet, J.
1977-01-01
Attitudes of 134 parents of children from 10 rural schools threatened with closure, and 56 parents of children from seven schools recently closed, were assessed by interview. Most parents opposed closure, and most gave educational reasons for their attitudes. (Author)
International Nuclear Information System (INIS)
2006-01-01
This Closure Report (CR) describes the activities performed to close CAU 115, Area 25 Test Cell A Facility, as presented in the NDEP-approved SAFER Plan (NNSA/NSO, 2004). The SAFER Plan includes a summary of the site history, process knowledge, and closure standards. This CR provides a summary of the completed closure activities, documentation of waste disposal, and analytical and radiological data to confirm that the remediation goals were met and to document final site conditions. The approved closure alternative as presented in the SAFER Plan for CAU 115 (NNSA/NSO, 2004) was clean closure; however, closure in place was implemented under a Record of Technical Change (ROTC) to the SAFER Plan when radiological surveys indicated that the concrete reactor pad was radiologically activated and could not be decontaminated to meet free release levels. The ROTC is included as Appendix G of this report. The objectives of closure were to remove any trapped residual liquids and gases, dispose regulated and hazardous waste, decontaminate removable radiological contamination, demolish and dispose aboveground structures, remove the dewar as a best management practice (BMP), and characterize and restrict access to all remaining radiological contamination. Radiological contaminants of concern (COCs) included cobalt-60, cesium-137, strontium-90, uranium-234/235/236/238, and plutonium-239/240. Additional COCs included Resource Conservation and Recovery Act (RCRA) metals, polychlorinated biphenyls (PCBs), and asbestos
Padrino, Juan C.; Sprittles, James; Lockerby, Duncan
2017-11-01
Thermophoresis refers to the forces on and motions of objects caused by temperature gradients when these objects are exposed to rarefied gases. This phenomenon can occur when the ratio of the gas mean free path to the characteristic physical length scale (Knudsen number) is not negligible. In this work, we obtain the thermophoretic force on a rigid, heat-conducting spherical particle immersed in a rarefied gas resulting from a uniform temperature gradient imposed far from the sphere. To this end, we model the gas dynamics using the steady, linearized version of the so-called regularized 13-moment equations (R13). This set of equations, derived from the Boltzmann equation using the moment method, provides closures to the mass, momentum, and energy conservation laws in the form of constitutive, transport equations for the stress and heat flux that extends the Navier-Stokes-Fourier model to include rarefaction effects. Integration of the pressure and stress on the surface of the sphere leads to the net force as a function of the Knudsen number, dimensionless temperature gradient, and particle-to-gas thermal conductivity ratio. Results from this expression are compared with predictions from other moment-based models as well as from kinetic models. Supported in the UK by the Engineering and Physical Sciences Research Council (EP/N016602/1).
300 Area Process Trenches Closure Plan
International Nuclear Information System (INIS)
Luke, S.N.
1994-01-01
Since 1987, Westinghouse Hanford Company has been a major contractor to the US Department of Energy, Richland Operations Office and has served as co-operator of the 300 Area Process Trenches, the waste management unit addressed in this closure plan. For the purposes of the Resource Conservation and Recovery Act, Westinghouse Hanford Company is identified as ''co-operator.'' The 300 Area Process Trenches Closure Plan (Revision 0) consists of a Resource Conservation and Recovery Act Part A Dangerous Waste Permit Application, Form 3 and a Resource Conservation and Recovery Act Closure Plan. An explanation of the Part A Permit Application, Form 3 submitted with this document is provided at the beginning of the Part A Section. The closure plan consists of nine chapters and six appendices. The 300 Area Process Trenches received dangerous waste discharges from research and development laboratories in the 300 Area and from fuels fabrication processes. This waste consisted of state-only toxic (WT02), corrosive (D002), chromium (D007), spent halogenated solvents (F001, F002, and F003), and spent nonhalogented solvent (F005). Accurate records are unavailable concerning the amount of dangerous waste discharged to the trenches. The estimated annual quantity of waste (item IV.B) reflects the total quantity of both regulated and nonregulated waste water that was discharged to the unit
Downstreamness: A concept to analyse basin closure
van Oel, P.R.; Krol, Martinus S.; Hoekstra, Arjen Ysbert
2011-01-01
In many places in the world, increasing water demands have led to the development of infrastructure for freshwater storage and irrigation. Especially in water-scarce regions, this development has led to a growing number of concerns about basin closure. These concerns ask for a structured approach
Scale separation closure and Alfven wave turbulence
International Nuclear Information System (INIS)
Chen, C.Y.; Mahajan, S.M.
1985-04-01
Based on the concept of scale separation between coherent response function and incoherent source for renormalized turbulence theories, a closure scheme is proposed. A model problem dealing with shear-Alfven wave turbulence is numerically solved; the solution explicitly shows expected turbulence features such as frequency shift from linear modes, band-broadening, and a power law dependence for the turbulence spectrum
VACUUM ASSISTED CLOSURE IN DIABETIC FOOT MANAGEMENT
Moganakannan; `Prema; Arun Sundara Rajan
2014-01-01
Comparision of vacuum assisted closure vs conventional dressing in management of diabetic foot patients. 30 patients were taken in that 15 underwent vacuum therapy and remaining 15 underwent conventional dressing.They were analysed by the development of granulation tissue and wound healing.The study showed Vac therapy is the best modality for management of diabetic foot patients.
Opening up closure. Semiotics across scales
Lemke
2000-01-01
The dynamic emergence of new levels of organization in complex systems is related to the semiotic reorganization of discrete/continuous variety at the level below as continuous/discrete meaning for the level above. In this view both the semiotic and the dynamic closure of system levels is reopened to allow the development and evolution of greater complexity.
Individual Consequences of Plant Closures and Cutbacks
DEFF Research Database (Denmark)
Andersen, Steen
1991-01-01
This thesis describes the segment of unemployment which has its origin in major closures and cutbacks. The argument for this is to make it possible to describe and to analyse a flow into and a flow out of a population of unemployed. Given a major dismissal the following questions are to be answer...
Hexone Storage and Treatment Facility closure plan
International Nuclear Information System (INIS)
1992-11-01
The HSTF is a storage and treatment unit subject to the requirements for the storage and treatment of dangerous waste. Closure is being conducted under interim status and will be completed pursuant to the requirements of Washington State Department of Ecology (Ecology) Dangerous Waste Regulations, Washington Administrative Code (WAC) 173-303-610 and WAC 173-303-640. Because dangerous waste does not include the source, special nuclear, and by-product material components of mixed waste, radionuclides are not within the scope of WAC 173-303 or of this closure plan. The information on radionuclides is provided only for general knowledge where appropriate. The known hazardous/dangerous waste remaining at the site before commencing other closure activities consists of the still vessels, a tarry sludge in the storage tanks, and residual contamination in equipment, piping, filters, etc. The treatment and removal of waste at the HSTF are closure activities as defined in the Resource Conservation and Recovery Act (RCRA) of 1976 and WAC 173-303
Synthesis of azaphenanthridines via anionic ring closure
DEFF Research Database (Denmark)
Hansen, Henriette Møller; Lysén, M.; Begtrup, M.
2005-01-01
A new and convergent synthesis of azaphenanthridines via an anionic ring closure is reported. Ortho-lithiation/in situ borylation of cyanopyridines produces the corresponding cyanopyridylboronic esters, which undergo a Suzuki-Miyaura cross-coupling to give the key intermediates. Addition of lithium...
Spontaneous closure of traumatic CSF otorrhoea following ...
African Journals Online (AJOL)
We present a 40 year-old male who sustained a head injury with left cerebrospinal fluid otorrhoea following a road traffic accident. Plain radiograph revealed a defect in the temporal bone extending in to the tympanomastoid area. Patient was managed conservatively with closure of the fistula and resolution of the leakage ...
Flower opening and closure: a review
Doorn, van W.G.; Meeteren, van U.
2003-01-01
Flower opening and closure are traits of a reproductive syndrome, as it allows pollen removal and/or pollination. Various types of opening can be distinguished such as nocturnal and diurnal and single or repetitive. Opening is generally due to cell expansion. Osmotic solute levels increase by the
Angle closure glaucoma in congenital ectropion uvea.
Wang, Grace M; Thuente, Daniel; Bohnsack, Brenda L
2018-06-01
Congenital ectropion uvea is a rare anomaly, which is associated with open, but dysplastic iridocorneal angles that cause childhood glaucoma. Herein, we present 3 cases of angle-closure glaucoma in children with congenital ectropion uvea. Three children were initially diagnosed with unilateral glaucoma secondary to congenital ectropion uvea at 7, 8 and 13 years of age. The three cases showed 360° of ectropion uvea and iris stromal atrophy in the affected eye. In one case, we have photographic documentation of progression to complete angle closure, which necessitated placement of a glaucoma drainage device 3 years after combined trabeculotomy and trabeculectomy. The 2 other cases, which presented as complete angle closure, also underwent glaucoma drainage device implantation. All three cases had early glaucoma drainage device encapsulation (within 4 months) and required additional surgery (cycloablation or trabeculectomy). Congenital ectropion uvea can be associated with angle-closure glaucoma, and placement of glaucoma drainage devices in all 3 of our cases showed early failure due to plate encapsulation. Glaucoma in congenital ectropion uvea requires attention to angle configuration and often requires multiple surgeries to obtain intraocular pressure control.
Automatically closing swing gate closure assembly
Chang, Shih-Chih; Schuck, William J.; Gilmore, Richard F.
1988-01-01
A swing gate closure assembly for nuclear reactor tipoff assembly wherein the swing gate is cammed open by a fuel element or spacer but is reliably closed at a desired closing rate primarily by hydraulic forces in the absence of a fuel charge.
Transcatheter Device Closure of Patent Ductus Arteriosus
International Nuclear Information System (INIS)
Sultan, M.; Ullah, M.; Sadiq, N.; Akhtar, K.; Akbar, H.
2014-01-01
Objective: To determine the efficacy, safety and immediate complications encountered during percutaneous device closure of patent ductus arteriosus (PDA). Study Design: Case series. Place and Duration of Study: Department of Paediatric Cardiology, AFIC/NIHD, Rawalpindi, from January 2005 to December 2010. Methodology: Consecutive 500 patients who underwent attempted transcatheter PDA device closure were included in the study. Device type position, success of closure and complications were described as frequency percentage. Results: In 491 cases (98.2%), PDA was successfully occluded including 4 cases (0.8%) where devices were dislodged but retrieved and redeployed in Cath laboratory. PDA occluder devices used in 448 cases (91%) while coils (single or multiple) were used in 42 cases (8.5%) and in one case (0.2%) ASD occluder device was used to occlude the PDA. There were 09 (1.8%) unsuccessful cases, 06 (1.2%) were abandoned as ducts were considered unsuitable for device closure, 02 (0.4%) devices dislodged and needed surgical retrieval and one case (0.2%) was abandoned due to faulty equipment. The narrowest PDA diameter ranged from 0.5 - 14 mm with mean of 4.5 +- 2.4 mm. There was a single (0.2%) mortality. Conclusion: Transcatheter occlusion of PDA by coil or occluder device is an effective therapeutic option with high success rate. Complication rate is low in the hands of skilled operators yet paediatric cardiac surgical back-up cover is mandatory. (author)
International Nuclear Information System (INIS)
Antony, M.S.; Britz, J.
1986-01-01
A compilation of experimental root-mean square radii, isotope shifts, ground-state magnetic dipole and electric quadrupole moments of nuclei 1≤A≤239 is presented. Shell, sub-subshell closures and changes in nuclear deformations discernible from data are displayed graphically. The nuclear charge distribution, for 1≤A≤ 239 nuclei deduced from Coulomb displacement energies is shown for comparison
Primary closure after carotid endarterectomy is not inferior to other closure techniques.
Avgerinos, Efthymios D; Chaer, Rabih A; Naddaf, Abdallah; El-Shazly, Omar M; Marone, Luke; Makaroun, Michel S
2016-09-01
Primary closure after carotid endarterectomy (CEA) has been much maligned as an inferior technique with worse outcomes than in patch closure. Our purpose was to compare perioperative and long-term results of different CEA closure techniques in a large institutional experience. A consecutive cohort of CEAs between January 1, 2000, and December 31, 2010, was retrospectively analyzed. Closure technique was used to divide patients into three groups: primary longitudinal arteriotomy closure (PRC), patch closure (PAC), and eversion closure (EVC). End points were perioperative events, long-term strokes, and restenosis ≥70%. Multivariate regression models were used to assess the effect of baseline predictors. There were 1737 CEA cases (bilateral, 143; mean age, 71.4 ± 9.3 years; 56.2% men; 35.3% symptomatic) performed during the study period with a mean clinical follow-up of 49.8 ± 36.4 months (range, 0-155 months). More men had primary closure, but other demographic and baseline symptoms were similar between groups. Half the patients had PAC, with the rest evenly distributed between PRC and EVC. The rate of nerve injury was 2.7%, the rate of reintervention for hematoma was 1.5%, and the length of hospital stay was 2.4 ± 3.0 days, with no significant differences among groups. The combined stroke and death rate was 2.5% overall and 3.9% and 1.7% in the symptomatic and asymptomatic cohort, respectively. Stroke and death rates were similar between groups: PRC, 11 (2.7%); PAC, 19 (2.2%); EVC, 13 (2.9%). Multivariate analysis showed baseline symptomatic disease (odds ratio, 2.4; P = .007) and heart failure (odds ratio, 3.1; P = .003) as predictors of perioperative stroke and death, but not the type of closure. Cox regression analysis demonstrated, among other risk factors, no statin use (hazard ratio, 2.1; P = .008) as a predictor of ipsilateral stroke and severe (glomerular filtration rate <30 mL/min/1.73 m(2)) renal insufficiency (hazard ratio, 2.6; P
Evaluation of proposed panel closure modifications at WIPP
Energy Technology Data Exchange (ETDEWEB)
Allen, Lawrence E.; Silva, Matthew K.; Channell, James K.; Abel, John F.; Morgan, Dudley R.
2001-12-31
A key component in the design of the WIPP repository is the installation of concrete structures as panel seals in the intake and exhaust drifts after a panel has been filled with waste containers. As noted in the EPA final rule, the panel seal closure system is intended to block brine flow between the waste panels at the WIPP. On April 17, 2001, the DOE proposed seven modifications to the EPA concerning the design of the panel closure system. EPA approval of these modifications is necessary since the details of the panel design are specified in EPA’s final rule as a condition for WIPP certification. However, the EPA has not determined whether a rulemaking would be required for these proposed design modifications. On September 4, 2001, the DOE withdrew the request, noting that it would be resubmitted on a future date. The Environmental Evaluation Group (EEG) contracted with two engineers, Dr. John Abel and Dr. Rusty Morgan, to evaluate the proposed modifications. The EEG has accepted the conclusions and recommendations from these two experts: 1) replacement of Salado Mass Concrete with a generic salt-based concrete; 2) replacement of the explosion wall with a construction wall; 3) replacement of freshwater grouting with salt-based grouting; 4) option to allow surface or underground mixing; and 5) option to allow up to one year for completion of closure. The proposed modification to allow local carbonate river rock as aggregate is acceptable pending demonstration that no problems will exist in the resulting concrete. The proposed modification to give the contractor discretion in removal of steel forms is not supported. Instead, several recommendations are made to specifically reduce the number of forms left, thereby reducing potential migration pathways.
Zannis, John; Angobaldo, Jeff; Marks, Malcolm; DeFranzo, Anthony; David, Lisa; Molnar, Joseph; Argenta, Louis
2009-04-01
Fasciotomy wounds can be a major contributor to length of stay for patients as well as a difficult reconstructive challenge. Once the compartment pressure has been relieved and stabilized, the wound should be closed as quickly and early as possible to avoid later complications. Skin grafting can lead to morbidity and scarring at both the donor and fasciotomy site. Primary closure results in a more functional and esthetic outcome with less morbidity for the patient, but can often be difficult to achieve secondary to edema, skin retraction, and skin edge necrosis. Our objective was to examine fasciotomy wound outcomes, including time to definitive closure, comparing traditional wet-to-dry dressings, and the vacuum-assisted closure (VAC) device. This retrospective chart review included a consecutive series of patients over a 10-year period. This series included 458 patients who underwent 804 fasciotomies. Of these fasciotomy wounds, 438 received exclusively VAC. dressings, 270 received only normal saline wet-to-dry dressings, and 96 were treated with a combination of both. Of the sample, 408 patients were treated with exclusively VAC therapy or wet-to-dry dressings and 50 patients were treated with a combination of both. In comparing all wounds, there was a statistically significant higher rate of primary closure using the VAC versus traditional wet-to-dry dressings (P lower extremities and P extremities). The time to primary closure of wounds was shorter in the VAC. group in comparison with the non-VAC group. This study has shown that the use of the VAC for fasciotomy wound closure results in a higher rate of primary closure versus traditional wet-to-dry dressings. In addition, the time to primary closure of wounds or time to skin grafting is shorter when the VAC was employed. The VAC used in the described settings decreases hospitalization time, allows for earlier rehabilitation, and ultimately leads to increased patient satisfaction.
The Rising Rate of Rural Hospital Closures.
Kaufman, Brystana G; Thomas, Sharita R; Randolph, Randy K; Perry, Julie R; Thompson, Kristie W; Holmes, George M; Pink, George H
2016-01-01
Since 2010, the rate of rural hospital closures has increased significantly. This study is a preliminary look at recent closures and a formative step in research to understand the causes and the impact on rural communities. The 2009 financial performance and market characteristics of rural hospitals that closed from 2010 through 2014 were compared to rural hospitals that remained open during the same period, stratified by critical access hospitals (CAHs) and other rural hospitals (ORHs). Differences were tested using Pearson's chi-square (categorical variables) and Wilcoxon rank test of medians. The relationships between negative operating margin and (1) market factors and (2) utilization/staffing factors were explored using logistic regression. In 2009, CAHs that subsequently closed from 2010 through 2014 had, in general, lower levels of profitability, liquidity, equity, patient volume, and staffing. In addition, ORHs that closed had smaller market shares and operated in markets with smaller populations compared to ORHs that remained open. Odds of unprofitability were associated with both market and utilization factors. Although half of the closed hospitals ceased providing health services altogether, the remainder have since converted to an alternative health care delivery model. Financial and market characteristics appear to be associated with closure of rural hospitals from 2010 through 2014, suggesting that it is possible to identify hospitals at risk of closure. As closure rates show no sign of abating, it is important to study the drivers of distress in rural hospitals, as well as the potential for alternative health care delivery models. © 2015 National Rural Health Association.
Colostomy closure: how to avoid complications.
Bischoff, Andrea; Levitt, Marc A; Lawal, Taiwo A; Peña, Alberto
2010-11-01
Colostomy is an operation frequently performed in pediatric surgery. Despite its benefits, it can produce significant morbidity. In a previous publication we presented our experience with the errors and complications that occurred during cases of colostomy creation. We now have focused in the morbidity related to the colostomy closure. The technical details that might have contributed to the minimal morbidity we experienced are described. The medical records of 649 patients who underwent colostomy closure over a 28-year period were retrospectively reviewed looking for complications following these procedures. Our perioperative protocol for colostomy closure consisted in: clear fluids by mouth and repeated proximal stoma irrigations 24 h prior to the operation. Administration of IV antibiotics during anesthesia induction and continued for 48 h. Meticulous surgical technique that included: packing of the proximal stoma, plastic drape to immobilize the surgical field, careful hemostasis, emphasis in avoiding contamination, cleaning the edge of the stomas to allow a good 2-layer, end-to-end anastomosis with separated long-term absorbable sutures, generous irrigation of the peritoneal cavity and subsequent layers with saline solution, closure by layers to avoid dead space, and avoidance of hematomas. No drains and no nasogastric tubes were used. Oral fluids were started the day after surgery and patients were discharged 48-72 h after the operation. The original diagnoses of the patients were: anorectal malformation (583), Hirschsprung's disease (53), and others (13). 10 patients (1.5%) had complications: 6 had intestinal obstruction (5 due to small bowel adhesions, 1 had temporary delay of the function of the anastomosis due to a severe size discrepancy between proximal and distal stoma with a distal microcolon) and 4 incisional hernias. There were no anastomotic dehiscences or wound infection. There was no bleeding, no anastomotic stricture and no mortality. Based on
9 CFR 318.301 - Containers and closures.
2010-01-01
... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Containers and closures. 318.301... Canning and Canned Products § 318.301 Containers and closures. (a) Examination and cleaning of empty containers. (1) Empty containers, closures, and flexible pouch roll stock shall be evaluated by the...
Crack closure and sequential effects in fatigue: A literature survey
Holmgren, M.
A literature survey of the phenomenon of crack closure is reported here. The state of the art is reviewed and several empirical formulas for determining the crack closure are compared with each other. Their properties, advantages and disadvantages are briefly discussed. Experimental techniques for determining the crack closure stress are presented and experimental data from the literature are reported.
40 CFR 267.143 - Financial assurance for closure.
2010-07-01
...), utilizing the certificate of insurance for closure specified at 40 CFR 264.151(e). (f) Corporate financial... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Financial assurance for closure. 267... PERMIT Financial Requirements § 267.143 Financial assurance for closure. The owner or operator must...
Permanent Closure of the TAN-664 Underground Storage Tank
Energy Technology Data Exchange (ETDEWEB)
Bradley K. Griffith
2011-12-01
This closure package documents the site assessment and permanent closure of the TAN-664 gasoline underground storage tank in accordance with the regulatory requirements established in 40 CFR 280.71, 'Technical Standards and Corrective Action Requirements for Owners and Operators of Underground Storage Tanks: Out-of-Service UST Systems and Closure.'
Neural tube closure depends on expression of Grainyhead-like 3 in multiple tissues.
De Castro, Sandra C P; Hirst, Caroline S; Savery, Dawn; Rolo, Ana; Lickert, Heiko; Andersen, Bogi; Copp, Andrew J; Greene, Nicholas D E
2018-03-15
Failure of neural tube closure leads to neural tube defects (NTDs), common congenital abnormalities in humans. Among the genes whose loss of function causes NTDs in mice, Grainyhead-like3 (Grhl3) is essential for spinal neural tube closure, with null mutants exhibiting fully penetrant spina bifida. During spinal neurulation Grhl3 is initially expressed in the surface (non-neural) ectoderm, subsequently in the neuroepithelial component of the neural folds and at the node-streak border, and finally in the hindgut endoderm. Here, we show that endoderm-specific knockout of Grhl3 causes late-arising spinal NTDs, preceded by increased ventral curvature of the caudal region which was shown previously to suppress closure of the spinal neural folds. This finding supports the hypothesis that diminished Grhl3 expression in the hindgut is the cause of spinal NTDs in the curly tail, carrying a hypomorphic Grhl3 allele. Complete loss of Grhl3 function produces a more severe phenotype in which closure fails earlier in neurulation, before the stage of onset of expression in the hindgut of wild-type embryos. This implicates additional tissues and NTD mechanisms in Grhl3 null embryos. Conditional knockout of Grhl3 in the neural plate and node-streak border has minimal effect on closure, suggesting that abnormal function of surface ectoderm, where Grhl3 transcripts are first detected, is primarily responsible for early failure of spinal neurulation in Grhl3 null embryos. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Periodic Closures as Adaptive Coral Reef Management in the Indo-Pacific
Directory of Open Access Journals (Sweden)
Josh Cinner
2006-06-01
Full Text Available This study explores the social, economic, and ecological context within which communities in Papua New Guinea and Indonesia use adaptive coral reef management. We tested whether periodic closures had positive effects on reef resources, and found that both the biomass and the average size of fishes commonly caught in Indo-Pacific subsistence fisheries were greater inside areas subject to periodic closures compared to sites with year-round open access. Surprisingly, both long-lived and short-lived species benefited from periodic closures. Our study sites were remote communities that shared many socioeconomic characteristics; these may be crucial to the effectiveness of adaptive management of reef resources through periodic closures. Some of these factors include exclusive tenure over marine resources, a body of traditional ecological knowledge that allows for the rapid assessment of resource conditions, social customs that facilitate compliance with closures, relatively small human populations, negligible migration, and a relatively low dependence on fisheries. This dynamic adaptive management system, in which communities manage their resources among multiple social and ecological baselines, contrasts with western fisheries management practices, centered on maintaining exploited populations at stable levels in which net production is maximized.
Magnetic moment densities in selected UTX compounds
Czech Academy of Sciences Publication Activity Database
Javorský, P.; Schweizer, J.; Givord, F.; Boucherle, J.-X.; Andreev, Alexander V.; Diviš, M.; Lelievre-Berna, E.; Sechovský, V.
2004-01-01
Roč. 350, - (2004), e131-e134 ISSN 0921-4526 R&D Projects: GA ČR GA202/03/0550 Institutional research plan: CEZ:AV0Z1010914 Keywords : uranium compound * polarized neutron scattering * magnetic moment Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.679, year: 2004
Moments, Mixed Methods, and Paradigm Dialogs
Denzin, Norman K.
2010-01-01
I reread the 50-year-old history of the qualitative inquiry that calls for triangulation and mixed methods. I briefly visit the disputes within the mixed methods community asking how did we get to where we are today, the period of mixed-multiple-methods advocacy, and Teddlie and Tashakkori's third methodological moment. (Contains 10 notes.)
The isotopic dipole moment of HDO
Energy Technology Data Exchange (ETDEWEB)
Assafrao, Denise; Mohallem, Jose R [Laboratorio de Atomos e Moleculas Especiais, Departamento de Fisica, ICEx, Universidade Federal de Minas Gerais, CP 702, 30123-970, Belo Horizonte, MG (Brazil)
2007-03-14
An adiabatic variational approximation is used to study the monodeuterated water molecule, HDO, accounting for the isotopic effect. The isotopic dipole moment, pointing from D to H, is then calculated for the first time, yielding (1.5 {+-} 0.1) x 10{sup -3} Debye, being helpful in the interpretation of experiments. (fast track communication)
Using Aha! Moments to Understand Leadership Theory
Moore, Lori L.; Lewis, Lauren J.
2012-01-01
As Huber (2002) noted, striving to understand how leadership is taught and learned is both a challenge and an opportunity facing leadership educators. This article describes the "Leadership Aha! Moment" assignment used in a leadership theory course to help students recognize the intersection of leadership theories and their daily lives while…
Moment matrices, border bases and radical computation
B. Mourrain; J.B. Lasserre; M. Laurent (Monique); P. Rostalski; P. Trebuchet (Philippe)
2013-01-01
htmlabstractIn this paper, we describe new methods to compute the radical (resp. real radical) of an ideal, assuming it complex (resp. real) variety is nte. The aim is to combine approaches for solving a system of polynomial equations with dual methods which involve moment matrices and
Moment matrices, border bases and radical computation
Lasserre, J.B.; Laurent, M.; Mourrain, B.; Rostalski, P.; Trébuchet, P.
2013-01-01
In this paper, we describe new methods to compute the radical (resp. real radical) of an ideal, assuming its complex (resp. real) variety is finite. The aim is to combine approaches for solving a system of polynomial equations with dual methods which involve moment matrices and semi-definite
Moment matrices, border bases and radical computation
B. Mourrain; J.B. Lasserre; M. Laurent (Monique); P. Rostalski; P. Trebuchet (Philippe)
2011-01-01
htmlabstractIn this paper, we describe new methods to compute the radical (resp. real radical) of an ideal, assuming it complex (resp. real) variety is nte. The aim is to combine approaches for solving a system of polynomial equations with dual methods which involve moment matrices and
Real object recognition using moment invariants
Indian Academy of Sciences (India)
are taken from different angles of view are the main features leading us to our objective. ... Two-dimensional moments of a digitally sampled M × M image that has gray function f (x, y), (x, .... in this paper. Information about the original colours of the objects is not used. .... multi-dimensional changes and recognition. Table 1.
Magnitude of localized magnetic moments in metals
International Nuclear Information System (INIS)
Kiwi, M.; Pestana, E.; Ramirez, R.
1979-01-01
The magnitude of the localized magnetic moment of a transition or rare earth element impurity in a metal is evaluated within the framework of the Anderson model. Rotational invariance is preserved throughout. Graphs of the magnitude of the magnetization as a function of the relevant parameters of the model are provided and discussed. (author)
Wonderful Life : Exploring Wonder in Meaningful Moments
van de Goor, Marie Jacqueline; Sools, Anna Maria; Westerhof, Gerben Johan; Bohlmeijer, Ernst Thomas
In this article, we bring the study of meaning together with the emerging field of study focusing on the emotions of wonder: wonder, enchantment, awe, and being moved. It is in meaningful moments that these two meet, and in our empirical study, we used the emotions of wonder as a lens to investigate
Rovibrational matrix elements of the multipole moments
Indian Academy of Sciences (India)
Rovibrational matrix elements of the multipole moments ℓ up to rank 10 and of the linear polarizability of the H2 molecule in the condensed phase have been computed taking into account the effect of the intermolecular potential. Comparison with gas phase matrix elements shows that the effect of solid state interactions is ...
The muon magnetic moment and new physics
Energy Technology Data Exchange (ETDEWEB)
Stoeckinger, Dominik, E-mail: Dominik.Stoeckinger@tu-dresden.de [Institute for Nuclear and Particle Physics (Germany)
2013-03-15
The impact of the muon magnetic moment measurement on physics beyond the Standard Model is briefly reviewed. Particular emphasis is given on the case of supersymmetry. The sensitivity of g - 2 to supersymmetry parameters and the potential for model discrimination and parameter measurements is described. The interplay between LHC data on the Higgs boson, limits on new particles, and g - 2 is discussed.
Search for a neutron electric dipole moment
Energy Technology Data Exchange (ETDEWEB)
Morse, J [Rutherford Appleton Laboratory, Chilton (U.K.)
1984-03-01
To search for evidence of a breakdown of symmetry under the time reversal transformation, a magnetic resonance measurement is made to detect an electric dipole moment (EDM) of ultracold neutrons stored for periods approximately= 60s in the presence of a strong electric field. The measured neutron EDM is (0.3 +- 4.8) x 10/sup -25/ ecm.
Transverse tails and higher order moments
International Nuclear Information System (INIS)
Spence, W.L.; Decker, F.J.; Woodley, M.D.
1993-05-01
The tails that may be engendered in a beam's transverse phase space distribution by, e.g., intrabunch wakefields and nonlinear magnetic fields, are all important diagnostic and object of tuning in linear colliders. Wire scanners or phosphorescent screen monitors yield one dimensional projected spatial profiles of such beams that are generically asymmetric around their centroids, and therefore require characterization by the third moment left-angle x 3 right-angle in addition to the conventional mean-square or second moment. A set of measurements spread over sufficient phase advance then allows the complete set left-angle x 3 right-angle, left-angle xx' 2 right-angle, left-angle x' 3 right-angle, and left-angle x 2 x'right-angle to be deduced -- the natural extension of the well-known ''emittance measurement'' treatment of second moments. The four third moments may be usefully decomposed into parts rotating in phase space at the β-tron frequency and at its third harmonic, each specified by a phase-advance-invariant amplitude and a phase. They provide a framework for the analysis and tuning of transverse wakefield tails
Expert judgement combination using moment methods
International Nuclear Information System (INIS)
Wisse, Bram; Bedford, Tim; Quigley, John
2008-01-01
Moment methods have been employed in decision analysis, partly to avoid the computational burden that decision models involving continuous probability distributions can suffer from. In the Bayes linear (BL) methodology prior judgements about uncertain quantities are specified using expectation (rather than probability) as the fundamental notion. BL provides a strong foundation for moment methods, rooted in work of De Finetti and Goldstein. The main objective of this paper is to discuss in what way expert assessments of moments can be combined, in a non-Bayesian way, to construct a prior assessment. We show that the linear pool can be justified in an analogous but technically different way to linear pools for probability assessments, and that this linear pool has a very convenient property: a linear pool of experts' assessments of moments is coherent if each of the experts has given coherent assessments. To determine the weights of the linear pool we give a method of performance based weighting analogous to Cooke's classical model and explore its properties. Finally, we compare its performance with the classical model on data gathered in applications of the classical model
Water hammer caused by closure of turbine safety spherical valves
Karadžić, U.; Bergant, A.; Vukoslavčević, P.
2010-08-01
This paper investigates water hammer effects caused by closure of spherical valves against the discharge. During the first phase of modernisation of Perućica high-head hydropower plant (HPP), Montenegro, safety spherical valves (inlet turbine valves) have been refurbished on the first two Pelton turbine units. The valve closure is controlled by the valve actuator (hydraulic servomotor). Because the torque acting on the valve body is dependent on flow conditions the valve closing time may vary significantly for different flow velocities (passive valve). For the passive valve the torques acting on the valve body should be considered in the valve model. The valve closing time results from numerical simulation. On the contrary, for the active valve the valve closing time is assumed prior to simulation. The spherical valve boundary condition is incorporated into the method of characteristics (MOC) algorithm. The staggered (diamond) grid in applying the MOC is used in this paper. The passive valve boundary condition is described by the water hammer equations, the valve equation that relates discharge to pressure head drop and the dynamic equation of the valve body motion (torque equation). The active valve boundary condition is described by the first two equations, respectively. Standard quasi-steady friction model is used for estimating friction losses in plant's tunnel and penstocks. Numerical results using both the active and the passive spherical valve models are compared with results of measurements. It has been found that the influence of flow conditions on the spherical valve closing time is minor for the cases considered. Computed and measured results agree reasonably well.
Water hammer caused by closure of turbine safety spherical valves
International Nuclear Information System (INIS)
Karadzic, U; Vukoslavcevic, P; Bergant, A
2010-01-01
This paper investigates water hammer effects caused by closure of spherical valves against the discharge. During the first phase of modernisation of Perucica high-head hydropower plant (HPP), Montenegro, safety spherical valves (inlet turbine valves) have been refurbished on the first two Pelton turbine units. The valve closure is controlled by the valve actuator (hydraulic servomotor). Because the torque acting on the valve body is dependent on flow conditions the valve closing time may vary significantly for different flow velocities (passive valve). For the passive valve the torques acting on the valve body should be considered in the valve model. The valve closing time results from numerical simulation. On the contrary, for the active valve the valve closing time is assumed prior to simulation. The spherical valve boundary condition is incorporated into the method of characteristics (MOC) algorithm. The staggered (diamond) grid in applying the MOC is used in this paper. The passive valve boundary condition is described by the water hammer equations, the valve equation that relates discharge to pressure head drop and the dynamic equation of the valve body motion (torque equation). The active valve boundary condition is described by the first two equations, respectively. Standard quasi-steady friction model is used for estimating friction losses in plant's tunnel and penstocks. Numerical results using both the active and the passive spherical valve models are compared with results of measurements. It has been found that the influence of flow conditions on the spherical valve closing time is minor for the cases considered. Computed and measured results agree reasonably well.
Water hammer caused by closure of turbine safety spherical valves
Energy Technology Data Exchange (ETDEWEB)
Karadzic, U; Vukoslavcevic, P [Faculty of Mechanical Engineering, University of Montenegro Dzordza Vasingtona nn, Podgorica, 81000 (Montenegro); Bergant, A, E-mail: uros.karadzic@ac.m [LitostrojPower d.o.o., Litostrojska 50, Ljubljana, 1000 (Slovenia)
2010-08-15
This paper investigates water hammer effects caused by closure of spherical valves against the discharge. During the first phase of modernisation of Perucica high-head hydropower plant (HPP), Montenegro, safety spherical valves (inlet turbine valves) have been refurbished on the first two Pelton turbine units. The valve closure is controlled by the valve actuator (hydraulic servomotor). Because the torque acting on the valve body is dependent on flow conditions the valve closing time may vary significantly for different flow velocities (passive valve). For the passive valve the torques acting on the valve body should be considered in the valve model. The valve closing time results from numerical simulation. On the contrary, for the active valve the valve closing time is assumed prior to simulation. The spherical valve boundary condition is incorporated into the method of characteristics (MOC) algorithm. The staggered (diamond) grid in applying the MOC is used in this paper. The passive valve boundary condition is described by the water hammer equations, the valve equation that relates discharge to pressure head drop and the dynamic equation of the valve body motion (torque equation). The active valve boundary condition is described by the first two equations, respectively. Standard quasi-steady friction model is used for estimating friction losses in plant's tunnel and penstocks. Numerical results using both the active and the passive spherical valve models are compared with results of measurements. It has been found that the influence of flow conditions on the spherical valve closing time is minor for the cases considered. Computed and measured results agree reasonably well.
Exploration of Learning Strategies Associated With Aha Learning Moments.
Pilcher, Jobeth W
2016-01-01
Educators recognize aha moments as powerful aspects of learning. Yet limited research has been performed regarding how to promote these learning moments. This article describes an exploratory study of aha learning moments as experienced and described by participants. Findings showed use of visuals, scenarios, storytelling, Socratic questions, and expert explanation led to aha learning moments. The findings provide guidance regarding the types of learning strategies that can be used to promote aha moments.
Trunk muscle activation. The effects of torso flexion, moment direction, and moment magnitude.
Lavender, S; Trafimow, J; Andersson, G B; Mayer, R S; Chen, I H
1994-04-01
This study was performed to quantify the electromyographic trunk muscle activities in response to variations in moment magnitude and direction while in forward-flexed postures. Recordings were made over eight trunk muscles in 19 subjects who maintained forward-flexed postures of 30 degrees and 60 degrees. In each of the two flexed postures, external moments of 20 Nm and 40 Nm were applied via a chest harness. The moment directions were varied in seven 30 degrees increments to a subject's right side, such that the direction of the applied load ranged from the upper body's anterior midsagittal plane (0 degree) to the posterior midsagittal plane (180 degrees). Statistical analyses yielded significant moment magnitude by moment-direction interaction effects for the EMG output from six of the eight muscles. Trunk flexion by moment-direction interactions were observed in the responses from three muscles. In general, the primary muscle supporting the torso and the applied load was the contralateral (left) erector spinae. The level of electromyographic activity in the anterior muscles was quite low, even with the posterior moment directions.
Trunk muscle cocontraction: the effects of moment direction and moment magnitude.
Lavender, S A; Tsuang, Y H; Andersson, G B; Hafezi, A; Shin, C C
1992-09-01
This study investigated the cocontraction of eight trunk muscles during the application of asymmetric loads to the torso. External moments of 10, 20, 30, 40, and 50 Nm were applied to the torso via a harness system. The direction of the applied moment was varied by 30 degrees increments to the subjects' right side between the sagittally symmetric orientations front and rear. Electromyographic (EMG) data from the left and right latissimus dorsi, erector spinae, external oblique, and rectus abdominus were collected from 10 subjects. The normalized EMG data were tested using multivariate and univariate analyses of variance procedures. These analyses showed significant interactions between the moment magnitude and the moment direction for seven of the eight muscles. Most of the interactions could be characterized as due to changes in muscle recruitment with changes in the direction of the external moment. Analysis of the relative activation levels, which were computed for each combination of moment magnitude and direction, indicated large changes in muscle recruitment due to asymmetry, but only small adjustments in the relative activation levels due to increased moment magnitude.
International Nuclear Information System (INIS)
Gelles, C. M.; Sheppard, F. R.
2002-01-01
This paper details the development of the Rocky Flats Integrated Closure Project Baseline - an innovative project management effort undertaken to ensure proactive management of the Rocky Flats Closure Contract in support of the Department's goal for achieving the safe closure of the Rocky Flats Environmental Technology Site (RFETS) in December 2006. The accelerated closure of RFETS is one of the most prominent projects within the Department of Energy (DOE) Environmental Management program. As the first major former weapons plant to be remediated and closed, it is a first-of-kind effort requiring the resolution of multiple complex technical and institutional challenges. Most significantly, the closure of RFETS is dependent upon the shipment of all special nuclear material and wastes to other DOE sites. The Department is actively working to strengthen project management across programs, and there is increasing external interest in this progress. The development of the Rocky Flats Integrated Closure Project Baseline represents a groundbreaking and cooperative effort to formalize the management of such a complex project across multiple sites and organizations. It is original in both scope and process, however it provides a useful precedent for the other ongoing project management efforts within the Environmental Management program
Control-surface hinge-moment calculations for a high-aspect-ratio supercritical wing
Perry, B., III
1978-01-01
The hinge moments, at selected flight conditions, resulting from deflecting two trailing edge control surfaces (one inboard and one midspan) on a high aspect ratio, swept, fuel conservative wing with a supercritical airfoil are estimated. Hinge moment results obtained from procedures which employ a recently developed transonic analysis are given. In this procedure a three dimensional inviscid transonic aerodynamics computer program is combined with a two dimensional turbulent boundary layer program in order to obtain an interacted solution. These results indicate that trends of the estimated hinge moment as a function of deflection angle are similar to those from experimental hinge moment measurements made on wind tunnel models with swept supercritical wings tested at similar values of free stream Mach number and angle of attack.
Ankle taping can reduce external ankle joint moments during drop landings on a tilted surface.
Sato, Nahoko; Nunome, Hiroyuki; Hopper, Luke S; Ikegami, Yasuo
2017-09-20
Ankle taping is commonly used to prevent ankle sprains. However, kinematic assessments investigating the biomechanical effects of ankle taping have provided inconclusive results. This study aimed to determine the effect of ankle taping on the external ankle joint moments during a drop landing on a tilted surface at 25°. Twenty-five participants performed landings on a tilted force platform that caused ankle inversion with and without ankle taping. Landing kinematics were captured using a motion capture system. External ankle inversion moment, the angular impulse due to the medio-lateral and vertical components of ground reaction force (GRF) and their moment arm lengths about the ankle joint were analysed. The foot plantar inclination relative to the ground was assessed. In the taping condition, the foot plantar inclination and ankle inversion angular impulse were reduced significantly compared to that of the control. The only component of the external inversion moment to change significantly in the taped condition was a shortened medio-lateral GRF moment arm length. It can be assumed that the ankle taping altered the foot plantar inclination relative to the ground, thereby shortening the moment arm of medio-lateral GRF that resulted in the reduced ankle inversion angular impulse.
Tocco, Maria Pia; Costantino, Alberto; Ballardini, Milva; D'Andrea, Claudio; Masala, Marcello; Merico, Eusebio; Mosillo, Luigi; Sordini, Paolo
2009-05-01
Postoperative deep sternal wound infection is a severe complication of cardiac surgery, with a high mortality rate and a high morbidity rate. The objective of this prospective study is to report our experience with the vacuum assisted closure (VAC) system for the management of deep wound infection. We also devised an innovative closure technique post VAC therapy using thermo reactive clips. The advantage of this technique is that the posterior face of the sternum does not have to be separated from the mediastinal structures thus minimising the risk of damage. From October 2006 to October 2008, we prospectively evaluated 21 patients affected by mediastinitis after sternotomy. Nineteen patients had sternotomy for coronary artery bypass grafting (CABG), one patient for aortic valve replacement (AVR) and another one for ascending aortic replacement (AAR). All patients were treated with the VAC system at the time of infection diagnosis. When the wound tissue appeared viable and the microbiological cultures were negative, the chest was closed using the most suitable procedure for the patient in question; nine patients were closed using pectoralis flaps, nine patients using Nitinol clips, one patient with a combined technique (use of Nitinol clips and muscle flap), one patient with a direct wound closure and another patient, who needed AAR with a homograft performed in another institution, was closed using sternal wires. We had no mortality; wound healing was successfully achieved in all patients. In more than 50% of the patients, the VAC therapy allowed direct sternal resynthesis. The average duration of the vacuum therapy was 26 days (range 14-37 days). VAC is a safe and effective option in the treatment of post-sternotomy mediastinitis, with excellent survival and immediate improvement of local wound conditions; furthermore, the use of Nitinol clips after VAC therapy demonstrated to be a safe and non-invasive option for sternal resynthesis. After VAC therapy, a
Boele van Hensbroek, Pieter; Wind, Jan; Dijkgraaf, Marcel G. W.; Busch, Olivier R. C.; Goslings, J. Carel
2009-01-01
Background This study was designed to systematically review the literature to assess which temporary abdominal closure (TAC) technique is associated with the highest delayed primary fascial closure (FC) rate. In some cases of abdominal trauma or infection, edema or packing precludes fascial closure
International Nuclear Information System (INIS)
Eberlein, Susan J.; Bergeron, Marcel P.; Kemp, Christopher J.; Hildebrand, R. Douglas; Aly, Alaa; Kozak, Matthew; Mehta, Sunil; Connelly, Michael
2013-01-01
The Office of River Protection under the U.S. Department of Energy (DOE) is pursuing closure of the Single-Shell Tank (SST) Waste Management Area (WMA) C as stipulated by the Hanford Federal Facility Agreement and Consent Order (HFFACO) under federal requirements and work tasks will be done under the State-approved closure plans and permits. An initial step in meeting the regulatory requirements is to develop a baseline risk assessment representing current conditions based on available characterization data and information collected at the WMA C location. The baseline risk assessment will be supporting a Resource Conservation and Recovery Act of 1976 (RCRA) Field Investigation (RFI)/Corrective Measures Study (CMS) for WMA closure and RCRA corrective action. Complying with the HFFACO conditions also involves developing a long-term closure Performance Assessment (PA) that evaluates human health and environmental impacts resulting from radionuclide inventories in residual wastes remaining in WMA C tanks and ancillary equipment. This PA is being developed to meet the requirements necessary for closure authorization under DOE Order 435.1 and Washington State Hazardous Waste Management Act. To meet the HFFACO conditions, the long-term closure risk analysis will include an evaluation of human health and environmental impacts from hazardous chemical inventories along with other performance Comprehensive Environmental Response, Compensation, and Liability Act Appropriate and Applicable Requirements (CERCLA ARARs) in residual wastes left in WMA C facilities after retrieval and removal. This closure risk analysis is needed to needed to comply with the requirements for permitted closure. Progress to date in developing a baseline risk assessment of WMA C has involved aspects of an evaluation of soil characterization and groundwater monitoring data collected as a part of the RFI/CMS and RCRA monitoring. Developing the long-term performance assessment aspects has involved the
Energy Technology Data Exchange (ETDEWEB)
Eberlein, Susan J.; Bergeron, Marcel P.; Kemp, Christopher J.
2013-11-11
The Office of River Protection under the U.S. Department of Energy (DOE) is pursuing closure of the Single-Shell Tank (SST) Waste Management Area (WMA) C as stipulated by the Hanford Federal Facility Agreement and Consent Order (HFFACO) under federal requirements and work tasks will be done under the State-approved closure plans and permits. An initial step in meeting the regulatory requirements is to develop a baseline risk assessment representing current conditions based on available characterization data and information collected at the WMA C location. The baseline risk assessment will be supporting a Resource Conservation and Recovery Act of 1976 (RCRA) Field Investigation (RFI)/Corrective Measures Study (CMS) for WMA closure and RCRA corrective action. Complying with the HFFACO conditions also involves developing a long-term closure Performance Assessment (PA) that evaluates human health and environmental impacts resulting from radionuclide inventories in residual wastes remaining in WMA C tanks and ancillary equipment. This PA is being developed to meet the requirements necessary for closure authorization under DOE Order 435.1 and Washington State Hazardous Waste Management Act. To meet the HFFACO conditions, the long-term closure risk analysis will include an evaluation of human health and environmental impacts from hazardous chemical inventories along with other performance Comprehensive Environmental Response, Compensation, and Liability Act Appropriate and Applicable Requirements (CERCLA ARARs) in residual wastes left in WMA C facilities after retrieval and removal. This closure risk analysis is needed to needed to comply with the requirements for permitted closure. Progress to date in developing a baseline risk assessment of WMA C has involved aspects of an evaluation of soil characterization and groundwater monitoring data collected as a part of the RFI/CMS and RCRA monitoring. Developing the long-term performance assessment aspects has involved the
Cloud condensation nuclei closure study on summer arctic aerosol
Martin, M.; Chang, R. Y.-W.; Sierau, B.; Sjogren, S.; Swietlicki, E.; Abbatt, J. P. D.; Leck, C.; Lohmann, U.
2011-11-01
We present an aerosol - cloud condensation nuclei (CCN) closure study on summer high Arctic aerosol based on measurements that were carried out in 2008 during the Arctic Summer Cloud Ocean Study (ASCOS) on board the Swedish ice breaker Oden. The data presented here were collected during a three-week time period in the pack ice (>85° N) when the icebreaker Oden was moored to an ice floe and drifted passively during the most biological active period into autumn freeze up conditions. CCN number concentrations were obtained using two CCN counters measuring at different supersaturations. The directly measured CCN number concentration was then compared with a CCN number concentration calculated using both bulk aerosol mass composition data from an aerosol mass spectrometer (AMS) and aerosol number size distributions obtained from a differential mobility particle sizer, assuming κ-Köhler theory, surface tension of water and an internally mixed aerosol. The last assumption was supported by measurements made with a hygroscopic tandem differential mobility analyzer (HTDMA) for particles >70 nm. For the two highest measured supersaturations, 0.73 and 0.41%, closure could not be achieved with the investigated settings concerning hygroscopicity and density. The calculated CCN number concentration was always higher than the measured one for those two supersaturations. This might be caused by a relative larger insoluble organic mass fraction of the smaller particles that activate at these supersaturations, which are thus less good CCN than the larger particles. On average, 36% of the mass measured with the AMS was organic mass. At 0.20, 0.15 and 0.10% supersaturation, closure could be achieved with different combinations of hygroscopic parameters and densities within the uncertainty range of the fit. The best agreement of the calculated CCN number concentration with the observed one was achieved when the organic fraction of the aerosol was treated as nearly water insoluble
International Nuclear Information System (INIS)
Alexander, P.
1993-01-01
A hydromagnetic equation system for the interplanetary collisionless solar wind is used to derive a set of conservation laws for that medium. It is found that every equation of the original system, including the closure relation, is related to one conservation law. The set that has been derived does not only include the traditional laws, but also a new one for the magnetic moment of the electrons. The conservation set is then used to obtain the space constants for the solar coronal expansion. The new law yields a constant that has not been predicted by other models
International Nuclear Information System (INIS)
2012-01-01
Appendix F of this report. The requirements are summarized in Section 5.2 of this report. The proposed post-closure requirements consist of visual inspections to determine the condition of postings and radiological surveys to verify contamination has not migrated. NNSA/NSO requests the following: (1) A Notice of Completion from the Nevada Division of Environmental Protection to NNSA/NSO for closure of CAU 547; and (2) The transfer of CAU 547 from Appendix III to Appendix IV, Closed Corrective Action Units, of the FFACO.
Energy Technology Data Exchange (ETDEWEB)
NSTec Environmental Restoration
2012-07-17
Appendix F of this report. The requirements are summarized in Section 5.2 of this report. The proposed post-closure requirements consist of visual inspections to determine the condition of postings and radiological surveys to verify contamination has not migrated. NNSA/NSO requests the following: (1) A Notice of Completion from the Nevada Division of Environmental Protection to NNSA/NSO for closure of CAU 547; and (2) The transfer of CAU 547 from Appendix III to Appendix IV, Closed Corrective Action Units, of the FFACO.
Assessment of consistent two-equation closure for forest flows
DEFF Research Database (Denmark)
Sogachev, Andrey; Cavar, Dalibor; Bechmann, Andreas
of grid turbulence and wall-bounded flow, the closure suggested is also valid for homogeneous shear flows commonly observed inside tall vegetative canopies. The present work assess the plant drag closure by comparing results of two different CFD models against observations derived over the forested area...... and can be applied for any twoequation closure. Results derived by different CFD models with k-epsilon and k-omega closure are similar and in good comparison with observations. Overall, numerical results show that the closure performs well, opening new possibilities for application to tasks related...... to the atmospheric boundary layer—where it is important to adequately account for the influences of vegetation....
Resource Conservation and Recovery Act Closure Plan for the Y-12 9409-5 Tank Storage Facility
International Nuclear Information System (INIS)
1995-02-01
This document presents information on the closure of the Y-12 9409-5 Tank Storage Facility. Topics discussed include: facility description; closure history; closure performance standard; partial closure; maximum waste inventory; closure activities; schedule; and postclosure care
Moment-to-Moment Optimal Branding in TV Commercials: Preventing Avoidance by Pulsing
Thales S. Teixeira; Michel Wedel; Rik Pieters
2010-01-01
We develop a conceptual framework about the impact that branding activity (the audiovisual representation of brands) and consumers' focused versus dispersed attention have on consumer moment-to-moment avoidance decisions during television advertising. We formalize this framework in a dynamic probit model and estimate it with Markov chain Monte Carlo methods. Data on avoidance through zapping, along with eye tracking on 31 commercials for nearly 2,000 participants, are used to calibrate the mo...
Roushdy, Alaa; Abd El Razek, Yasmeen; Mamdouh Tawfik, Ahmed
2018-01-01
To determine anatomic and hemodynamic echocardiographic predictors for patent ductus arteriosus (PDA) device vs coil closure. Seventy-six patients who were referred for elective transcatheter PDA closure were enrolled in the study. All patients underwent full echocardiogram including measurement of the PDA pulmonary end diameter, color flow width and extent, peak and end-diastolic Doppler gradients across the duct, diastolic flow reversal, left atrial dimensions and volume, left ventricular sphericity index, and volumes. The study group was subdivided into 2 subgroups based on the mode of PDA closure whether by coil (n = 42) or device (n = 34). Using univariate analysis there was a highly significant difference between the 2 groups as regard the pulmonary end diameter measured in both the suprasternal and parasternal short-axis views as well as the color flow width and color flow extent (P closure group had statistically significant higher end-systolic and end-diastolic volumes indexed, left atrial volume, and diastolic flow reversal. Receiver operating characteristic curve analysis showed a pulmonary end diameter cutoff point from the suprasternal view > 2.5 mm and from parasternal short-axis view > 2.61 mm to have the highest balanced sensitivity and specificity to predict the likelihood for device closure (AUC 0.971 and 0.979 respectively). The pulmonary end diameter measured from the suprasternal view was the most independent predictor of device closure. The selection between PDA coil or device closure can be done on the basis of multiple anatomic and hemodynamic echocardiographic variables. © 2017 Wiley Periodicals, Inc.
A regenerative approach towards mucosal fenestration closure
Gandi, Padma; Anumala, Naveen; Reddy, Amarender; Viswa Chandra, Rampalli
2013-01-01
Mucosal fenestration is an opening or an interstice through the oral mucosa. A lesion which occurs with greater frequency than generally realised, its occurrence is attributed to a myriad of causes. Mucogingival procedures including connective tissue grafts, free gingival grafts and lateral pedicle grafts are generally considered to be the treatment of choice in the closure of a mucosal fenestration. More often, these procedures are performed in conjunction with other procedures such as periradicular surgery and with bone grafts. However, the concomitant use of gingival grafts and bone grafts in mucosal fenestrations secondary to infections in sites exhibiting severe bone loss is highly debatable. In this article, we report two cases of mucosal fenestrations secondary to trauma and their management by regenerative periodontal surgery with the placement of guided tissue regeneration membrane and bone graft. The final outcome was a complete closure of the fenestration in both the cases. PMID:23749826
Improving environmental performance through mine closure planning
International Nuclear Information System (INIS)
McKee, W.; McKenna, G.
1998-01-01
Syncrude has been investigating landscape redevelopment concepts since 1995 after a two-year tailings technology selection study resulted in a major shift in their long-term tailings disposal strategy. The change from fluid disposal to solid disposal of tailings leads to a different landscape, incorporating a new water material type, new landforms and a new schedule of reclamation activity. A multidisciplinary approach was needed to assess, design and develop the final landscape. Planning approach in progress at Syncrude Canada was described, and the basic concepts and tools of closure planning discovered to date were outlined. The economic impacts of closure planning on mining and tailings operations in general, were discussed. 14 refs
Exchange current contributions to isoscalar magnetic moments
International Nuclear Information System (INIS)
Arima, A.; Bentz, W.; Ichii, S.
1986-01-01
In this work the authors have investigated two recent suggestions which indicated appreciable exchange current contributions to isoscalar magnetic moments. On account of gauge invariance the authors found that in both treatments certain important terms seem to be omitted. The authors then performed explicit calculations using a one-boson exchange model for the exchange current operator. The authors found that the results are sensitive to the ratio of coupling constants g/sub σNN///g/sub ωNN/. Due to this fact it is difficult to draw quantitative conclusions. In the present model calculation the authors found that both g/sub s/(0) and g/sub 1//sup 0/ are enhanced by about 3% to 4%, resulting in non-negligible corrections to isoscalar magnetic moments
Higher Mellin moments for charged current DIS
International Nuclear Information System (INIS)
Rogal, M.; Moch, S.
2007-06-01
We report on our recent results for deep-inelastic neutrino(ν)-proton(P) scattering. We have computed the perturbative QCD corrections to three loops for the charged current structure functions F 2 , F L and F 3 for the combination νP- anti νP. In leading twist approximation we have calculated the first six odd-integer Mellin moments in the case of F 2 and F L and the first six even-integer moments in the case of F 3 . As a new result we have obtained the coefficient functions to O(α 3 s ) and we have found the corresponding anomalous dimensions to agree with known results in the literature. (orig.)
Impurity-induced moments in underdoped cuprates
International Nuclear Information System (INIS)
Khaliullin, G.; Kilian, R.; Krivenko, S.; Fulde, P.
1997-01-01
We examine the effect of a nonmagnetic impurity in a two-dimensional spin liquid in the spin-gap phase, employing a drone-fermion representation of spin-1/2 operators. The properties of the local moment induced in the vicinity of the impurity are investigated and an expression for the nuclear-magnetic-resonance Knight shift is derived, which we compare with experimental results. Introducing a second impurity into the spin liquid an antiferromagnetic interaction between the moments is found when the two impurities are located on different sublattices. The presence of many impurities leads to a screening of this interaction as is shown by means of a coherent-potential approximation. Further, the Kondo screening of an impurity-induced local spin by charge carriers is discussed. copyright 1997 The American Physical Society
Inverse-moment chiral sum rules
International Nuclear Information System (INIS)
Golowich, E.; Kambor, J.
1996-01-01
A general class of inverse-moment sum rules was previously derived by the authors in a chiral perturbation theory (ChPT) study at two-loop order of the isospin and hypercharge vector-current propagators. Here, we address the evaluation of the inverse-moment sum rules in terms of existing data and theoretical constraints. Two kinds of sum rules are seen to occur: those which contain as-yet undetermined O(q 6 ) counterterms and those free of such quantities. We use the former to obtain phenomenological evaluations of two O(q 6 ) counterterms. Light is shed on the important but difficult issue regarding contributions of higher orders in the ChPT expansion. copyright 1996 The American Physical Society
Electric Dipole Moment Results from lattice QCD
Dragos, Jack; Luu, Thomas; Shindler, Andrea; de Vries, Jordy
2018-03-01
We utilize the gradient flow to define and calculate electric dipole moments induced by the strong QCD θ-term and the dimension-6 Weinberg operator. The gradient flow is a promising tool to simplify the renormalization pattern of local operators. The results of the nucleon electric dipole moments are calculated on PACS-CS gauge fields (available from the ILDG) using Nf = 2+1, of discrete size 323×64 and spacing a ≃ 0.09 fm. These gauge fields use a renormalization-group improved gauge action and a nonperturbatively O(a) improved clover quark action at β = 1.90, with cSW = 1.715. The calculation is performed at pion masses of mπ ≃ 411, 701 MeV.
Electric Dipole Moment Results from lattice QCD
Directory of Open Access Journals (Sweden)
Dragos Jack
2018-01-01
Full Text Available We utilize the gradient flow to define and calculate electric dipole moments induced by the strong QCD θ-term and the dimension-6 Weinberg operator. The gradient flow is a promising tool to simplify the renormalization pattern of local operators. The results of the nucleon electric dipole moments are calculated on PACS-CS gauge fields (available from the ILDG using Nf = 2+1, of discrete size 323×64 and spacing a ≃ 0.09 fm. These gauge fields use a renormalization-group improved gauge action and a nonperturbatively O(a improved clover quark action at β = 1.90, with cSW = 1.715. The calculation is performed at pion masses of mπ ≃ 411, 701 MeV.
Solar wind velocity and geomagnetic moment variations
International Nuclear Information System (INIS)
Kalinin, Yu.D.; Rozanova, T.S.
1982-01-01
The mean year values of the solar wind velocity have been calculated from the mean-year values of a geomagnetic activity index am according to the Svalgard equation of regression for the pe-- riod from 1930 to 1960. For the same years the values of the geomagnetic moment M and separately of its ''inner'' (causes of which'' are inside the Earth) and ''external'' (causes of which are outside the Earth) parts have been calculated from the mean year data of 12 magnetic observatories. The proof of the presence of the 11-year variation in the moment M has been obtained. It is concluded that the 11-year variations in M result from the variations of the solar wind velocity
Theater gateway closure: a strategic level barricade
logistical planners at the strategic level can anticipate or mitigate the effects of a theater gateway closure on military operations. Through two...that at the strategic level the effects are based on the economic and diplomatic elements of the national power, affecting proportionally sustainment...Finally, logistical planners at the strategic level need to have a vast and ample knowledge and understanding of the operational environment to
Calcined solids storage facility closure study
International Nuclear Information System (INIS)
Dahlmeir, M.M.; Tuott, L.C.; Spaulding, B.C.
1998-02-01
The disposal of radioactive wastes now stored at the Idaho National Engineering and Environmental Laboratory is currently mandated under a open-quotes Settlement Agreementclose quotes (or open-quotes Batt Agreementclose quotes) between the Department of Energy and the State of Idaho. Under this agreement, all high-level waste must be treated as necessary to meet the disposal criteria and disposed of or made road ready to ship from the INEEL by 2035. In order to comply with this agreement, all calcined waste produced in the New Waste Calcining Facility and stored in the Calcined Solids Facility must be treated and disposed of by 2035. Several treatment options for the calcined waste have been studied in support of the High-Level Waste Environmental Impact Statement. Two treatment methods studied, referred to as the TRU Waste Separations Options, involve the separation of the high-level waste (calcine) into TRU waste and low-level waste (Class A or Class C). Following treatment, the TRU waste would be sent to the Waste Isolation Pilot Plant (WIPP) for final storage. It has been proposed that the low-level waste be disposed of in the Tank Farm Facility and/or the Calcined Solids Storage Facility following Resource Conservation and Recovery Act closure. In order to use the seven Bin Sets making up the Calcined Solids Storage Facility as a low-level waste landfill, the facility must first be closed to Resource Conservation and Recovery Act (RCRA) standards. This study identifies and discusses two basic methods available to close the Calcined Solids Storage Facility under the RCRA - Risk-Based Clean Closure and Closure to Landfill Standards. In addition to the closure methods, the regulatory requirements and issues associated with turning the Calcined Solids Storage Facility into an NRC low-level waste landfill or filling the bin voids with clean grout are discussed
Base Closure: A Road Map for Completion
1991-03-22
leadership . At the same time, he should issue written press releases. Selected senior leaders from the base should be briefed separately from key community...they will hold with other agencies on base. These matters should be the commander’s call; they will reflect his style of leadership and preference for...base closure. He alone must foresee what can most likely go wrong as well as what should go right in this arduous process. DCNSIZING AN ORGANIZATIN The
The Galois closure of Drinfeld modular towers
DEFF Research Database (Denmark)
Bassa, Alp; Beelen, Peter
2011-01-01
In this article we study Drinfeld modular curves X0(pn) associated to congruence subgroups Γ0(pn) of GL(2,Fq[T]) where p is a prime of Fq[T]. For n>r>0 we compute the extension degrees and investigate the structure of the Galois closures of the covers X0(pn)→X0(pr) and some of their variations...
Calcined solids storage facility closure study
Energy Technology Data Exchange (ETDEWEB)
Dahlmeir, M.M.; Tuott, L.C.; Spaulding, B.C. [and others
1998-02-01
The disposal of radioactive wastes now stored at the Idaho National Engineering and Environmental Laboratory is currently mandated under a {open_quotes}Settlement Agreement{close_quotes} (or {open_quotes}Batt Agreement{close_quotes}) between the Department of Energy and the State of Idaho. Under this agreement, all high-level waste must be treated as necessary to meet the disposal criteria and disposed of or made road ready to ship from the INEEL by 2035. In order to comply with this agreement, all calcined waste produced in the New Waste Calcining Facility and stored in the Calcined Solids Facility must be treated and disposed of by 2035. Several treatment options for the calcined waste have been studied in support of the High-Level Waste Environmental Impact Statement. Two treatment methods studied, referred to as the TRU Waste Separations Options, involve the separation of the high-level waste (calcine) into TRU waste and low-level waste (Class A or Class C). Following treatment, the TRU waste would be sent to the Waste Isolation Pilot Plant (WIPP) for final storage. It has been proposed that the low-level waste be disposed of in the Tank Farm Facility and/or the Calcined Solids Storage Facility following Resource Conservation and Recovery Act closure. In order to use the seven Bin Sets making up the Calcined Solids Storage Facility as a low-level waste landfill, the facility must first be closed to Resource Conservation and Recovery Act (RCRA) standards. This study identifies and discusses two basic methods available to close the Calcined Solids Storage Facility under the RCRA - Risk-Based Clean Closure and Closure to Landfill Standards. In addition to the closure methods, the regulatory requirements and issues associated with turning the Calcined Solids Storage Facility into an NRC low-level waste landfill or filling the bin voids with clean grout are discussed.
Evaluation of Two Energy Balance Closure Parametrizations
Eder, Fabian; De Roo, Frederik; Kohnert, Katrin; Desjardins, Raymond L.; Schmid, Hans Peter; Mauder, Matthias
2014-05-01
A general lack of energy balance closure indicates that tower-based eddy-covariance (EC) measurements underestimate turbulent heat fluxes, which calls for robust correction schemes. Two parametrization approaches that can be found in the literature were tested using data from the Canadian Twin Otter research aircraft and from tower-based measurements of the German Terrestrial Environmental Observatories (TERENO) programme. Our analysis shows that the approach of Huang et al. (Boundary-Layer Meteorol 127:273-292, 2008), based on large-eddy simulation, is not applicable to typical near-surface flux measurements because it was developed for heights above the surface layer and over homogeneous terrain. The biggest shortcoming of this parametrization is that the grid resolution of the model was too coarse so that the surface layer, where EC measurements are usually made, is not properly resolved. The empirical approach of Panin and Bernhofer (Izvestiya Atmos Oceanic Phys 44:701-716, 2008) considers landscape-level roughness heterogeneities that induce secondary circulations and at least gives a qualitative estimate of the energy balance closure. However, it does not consider any feature of landscape-scale heterogeneity other than surface roughness, such as surface temperature, surface moisture or topography. The failures of both approaches might indicate that the influence of mesoscale structures is not a sufficient explanation for the energy balance closure problem. However, our analysis of different wind-direction sectors shows that the upwind landscape-scale heterogeneity indeed influences the energy balance closure determined from tower flux data. We also analyzed the aircraft measurements with respect to the partitioning of the "missing energy" between sensible and latent heat fluxes and we could confirm the assumption of scalar similarity only for Bowen ratios 1.
Moments, positive polynomials and their applications
Lasserre, Jean Bernard
2009-01-01
Many important applications in global optimization, algebra, probability and statistics, applied mathematics, control theory, financial mathematics, inverse problems, etc. can be modeled as a particular instance of the Generalized Moment Problem (GMP) . This book introduces a new general methodology to solve the GMP when its data are polynomials and basic semi-algebraic sets. This methodology combines semidefinite programming with recent results from real algebraic geometry to provide a hierarchy of semidefinite relaxations converging to the desired optimal value. Applied on appropriate cones,
A big measurement of a small moment
E Sauer, B.; Devlin, J. A.; Rabey, I. M.
2017-07-01
A beam of ThO molecules has been used to make the most precise measurement of the electron’s electric dipole moment (EDM) to date. In their recent paper, the ACME collaboration set out in detail their experimental and data analysis techniques. In a tour-de-force, they explain the many ways in which their apparatus can produce a signal which mimics the EDM and show how these systematic effects are measured and controlled.
Some special moments from last month
Claudia Marcelloni de Oliveira
Integration of the three shells into the ATLAS pixel barrel last month. Lowering of the first sector of the MDT Muon Big Wheel on side C in the ATLAS cavern in December 2006. Some intense moment during the first ATLAS integration run from the main ATLAS control room. Muriel was one of the 20000 ATLAS cavern visitors in 2006 to enjoy herself during her visit.
Nuclear moments of radioactive nuclei. Final report
International Nuclear Information System (INIS)
Greenlees, G.W.
1985-01-01
An unsuccessful attempt was made to study nuclear moments of radioactive nuclear using laser spectroscopy. Although preliminary tests had indicated a sensitivity sufficient to observe signals of fluxes less than one atom/s no resonance fluorescence was detected. Activity measurements showed several hundred nuclei per second were in the beam; therefore it was postulated that, due to the the reactivity of the 126 Ba and sodium used, contaminants were the probable source of negative results. 3 refs., 2 figs
Nuclear moments of inertia at high spins
International Nuclear Information System (INIS)
Deleplanque, M.A.
1984-01-01
For nuclei in high spin states a yrast-like part of a continuum γ-ray spectrum shows naturally how angular momentum is generated as a function of frequency. In rotational nuclei, the rotational frequency is omega = dE/dI approx. E/sub γ/2, half the collective E2 transition energy. The height of the spectrum for a rotor is proportional to dN/dE/sub γ/ = dI/4d omega. dI/d omega is a dynamic (second derivative of energy with spin) moment of inertia. It contains both alignments and collective effects and is therefore an effective moment of inertia J/sub eff//sup (2)/. It shows how much angular momentum is generated at each frequency. If the collective moment of inertia J/sub band//sup (2)/(omega) is measured (from γ-γ correlation experiments) for the same system, the collective and aligned (Δi) contributions to the increase of angular momentum ΔI in a frequency interval Δ omega can be separated: Δi/ΔI = 1 - J/sub band//sup (2)//J/sub eff//sup (2)/. This is at present the only way to extract such detailed information at the highest spin states where discrete lines cannot be resolved. An example of the spectra obtained in several Er nuclei is shown. They are plotted in units of the moment of inertia J/sub eff//sup (2)/. The high-energy part of the spectra has been corrected for incomplete feeding at these frequencies
Model Reduction using Vorobyev Moment Problem
Czech Academy of Sciences Publication Activity Database
Strakoš, Zdeněk
2009-01-01
Roč. 51, č. 3 (2009), s. 363-379 ISSN 1017-1398 R&D Projects: GA AV ČR IAA100300802 Institutional research plan: CEZ:AV0Z10300504 Keywords : matching moments * model reduction * Krylov subspace methods * conjugate gradient method * Lanczos method * Arnoldi method * Gauss-Christoffel quadrature * scattering amplitude Subject RIV: BA - General Mathematics Impact factor: 0.716, year: 2009
CP-violation and electric dipole moments
Energy Technology Data Exchange (ETDEWEB)
Le Dall, Matthias; Ritz, Adam, E-mail: aritz@uvic.ca [University of Victoria, Department of Physics and Astronomy (Canada)
2013-03-15
Searches for intrinsic electric dipole moments of nucleons, atoms and molecules are precision flavour-diagonal probes of new -odd physics. We review and summarise the effective field theory analysis of the observable EDMs in terms of a general set of CP-odd operators at 1 GeV, and the ensuing model-independent constraints on new physics. We also discuss the implications for supersymmetric models, in light of the mass limits emerging from the LHC.
Monte Carlo Volcano Seismic Moment Tensors
Waite, G. P.; Brill, K. A.; Lanza, F.
2015-12-01
Inverse modeling of volcano seismic sources can provide insight into the geometry and dynamics of volcanic conduits. But given the logistical challenges of working on an active volcano, seismic networks are typically deficient in spatial and temporal coverage; this potentially leads to large errors in source models. In addition, uncertainties in the centroid location and moment-tensor components, including volumetric components, are difficult to constrain from the linear inversion results, which leads to a poor understanding of the model space. In this study, we employ a nonlinear inversion using a Monte Carlo scheme with the objective of defining robustly resolved elements of model space. The model space is randomized by centroid location and moment tensor eigenvectors. Point sources densely sample the summit area and moment tensors are constrained to a randomly chosen geometry within the inversion; Green's functions for the random moment tensors are all calculated from modeled single forces, making the nonlinear inversion computationally reasonable. We apply this method to very-long-period (VLP) seismic events that accompany minor eruptions at Fuego volcano, Guatemala. The library of single force Green's functions is computed with a 3D finite-difference modeling algorithm through a homogeneous velocity-density model that includes topography, for a 3D grid of nodes, spaced 40 m apart, within the summit region. The homogenous velocity and density model is justified by long wavelength of VLP data. The nonlinear inversion reveals well resolved model features and informs the interpretation through a better understanding of the possible models. This approach can also be used to evaluate possible station geometries in order to optimize networks prior to deployment.
Phenomenology of convection-parameterization closure
Directory of Open Access Journals (Sweden)
J.-I. Yano
2013-04-01
Full Text Available Closure is a problem of defining the convective intensity in a given parameterization. In spite of many years of efforts and progress, it is still considered an overall unresolved problem. The present article reviews this problem from phenomenological perspectives. The physical variables that may contribute in defining the convective intensity are listed, and their statistical significances identified by observational data analyses are reviewed. A possibility is discussed for identifying a correct closure hypothesis by performing a linear stability analysis of tropical convectively coupled waves with various different closure hypotheses. Various individual theoretical issues are considered from various different perspectives. The review also emphasizes that the dominant physical factors controlling convection differ between the tropics and extra-tropics, as well as between oceanic and land areas. Both observational as well as theoretical analyses, often focused on the tropics, do not necessarily lead to conclusions consistent with our operational experiences focused on midlatitudes. Though we emphasize the importance of the interplays between these observational, theoretical and operational perspectives, we also face challenges for establishing a solid research framework that is universally applicable. An energy cycle framework is suggested as such a candidate.
Stochastic particle acceleration and statistical closures
International Nuclear Information System (INIS)
Dimits, A.M.; Krommes, J.A.
1985-10-01
In a recent paper, Maasjost and Elsasser (ME) concluded, from the results of numerical experiments and heuristic arguments, that the Bourret and the direct-interaction approximation (DIA) are ''of no use in connection with the stochastic acceleration problem'' because (1) their predictions were equivalent to that of the simpler Fokker-Planck (FP) theory, and (2) either all or none of the closures were in good agreement with the data. Here some analytically tractable cases are studied and used to test the accuracy of these closures. The cause of the discrepancy (2) is found to be the highly non-Gaussian nature of the force used by ME, a point not stressed by them. For the case where the force is a position-independent Ornstein-Uhlenbeck (i.e., Gaussian) process, an effective Kubo number K can be defined. For K << 1 an FP description is adequate, and conclusion (1) of ME follows; however, for K greater than or equal to 1 the DIA behaves much better qualitatively than the other two closures. For the non-Gaussian stochastic force used by ME, all common approximations fail, in agreement with (2)
Spins, moments and radii of Cd isotopes
Hammen, Michael
The complex nature of the nucleon-nucleon interaction and the wide range of systems covered by the roughly 3000 known nuclides leads to a multitude of effects observed in nuclear structure. Among the most prominent ones is the occurence of shell closures at so-called ”magic numbers”, which are explained by the nuclear shell model. Although the shell model already is on duty for several decades, it is still constantly extended and improved. For this process of extension, ﬁne adjustment and veriﬁcation, it is important to have experimental data of nuclear properties, especially at crucial points like in the vicinity of shell closures. This is the motivation for the work performed in this thesis: the measurement and analysis of nuclear ground state properties of the isotopic chain of $^{100−130}$Cd by collinear laser spectroscopy. The experiment was conducted at ISOLDE/CERN using the collinear laser spectroscopy apparatus COLLAPS. This experiment is the continuation of a run on neutral atomic cadmium f...
USING MAGNETIC MOMENTS TO UNVEIL THE NUCLEAR STRUCTURE OF LOW-SPIN NUCLEAR STATES
Directory of Open Access Journals (Sweden)
Diego A. Torres
2011-07-01
Full Text Available The experimental study of magnetic moments for nuclear states near the ground state, I ≤ 2, provides a powerful tool to test nuclear structure models. Traditionally, the use of Coulomb excitation reactions has been used to study low spin states, mostly I = 2. The use of alternative reaction channels, such as α transfer, for the production of radioactive species that, otherwise, will be only produced in future radioactive beam facilities has proved to be an alternative to measure not only excited states with I > 2, but to populate and study long-live radioactive nuclei. This contribution will present the experimental tools and challenges for the use of the transient field technique for the measurement of g factors in nuclear states with I ≤ 2, using Coulomb excitation and α-transfer reactions. Recent examples of experimental results near the N = 50 shell closure, and the experimental challenges for future implementations with radioactive beams, will be discussed.
Relativistic dynamics of point magnetic moment
Rafelski, Johann; Formanek, Martin; Steinmetz, Andrew
2018-01-01
The covariant motion of a classical point particle with magnetic moment in the presence of (external) electromagnetic fields is revisited. We are interested in understanding extensions to the Lorentz force involving point particle magnetic moment (Stern-Gerlach force) and how the spin precession dynamics is modified for consistency. We introduce spin as a classical particle property inherent to Poincaré symmetry of space-time. We propose a covariant formulation of the magnetic force based on a `magnetic' 4-potential and show how the point particle magnetic moment relates to the Amperian (current loop) and Gilbertian (magnetic monopole) descriptions. We show that covariant spin precession lacks a unique form and discuss the connection to g-2 anomaly. We consider the variational action principle and find that a consistent extension of the Lorentz force to include magnetic spin force is not straightforward. We look at non-covariant particle dynamics, and present a short introduction to the dynamics of (neutral) particles hit by a laser pulse of arbitrary shape.
Moments of the Wigner delay times
International Nuclear Information System (INIS)
Berkolaiko, Gregory; Kuipers, Jack
2010-01-01
The Wigner time delay is a measure of the time spent by a particle inside the scattering region of an open system. For chaotic systems, the statistics of the individual delay times (whose average is the Wigner time delay) are thought to be well described by random matrix theory. Here we present a semiclassical derivation showing the validity of random matrix results. In order to simplify the semiclassical treatment, we express the moments of the delay times in terms of correlation functions of scattering matrices at different energies. In the semiclassical approximation, the elements of the scattering matrix are given in terms of the classical scattering trajectories, requiring one to study correlations between sets of such trajectories. We describe the structure of correlated sets of trajectories and formulate the rules for their evaluation to the leading order in inverse channel number. This allows us to derive a polynomial equation satisfied by the generating function of the moments. Along with showing the agreement of our semiclassical results with the moments predicted by random matrix theory, we infer that the scattering matrix is unitary to all orders in the semiclassical approximation.
On the multipole moments of charge distributions
International Nuclear Information System (INIS)
Khare, P.L.
1977-01-01
There are two different standard methods for showing the equivalence of a charge distribution in a small volume tau surrounding a point O, to the superposition of a monopole, a dipole, a quadrupole and poles of higher moments at the point O: (a) to show that the electrostatic potential due to the charge distribution at an outside point is the same as due to these superposed multipoles (including a monopole). (b) to show that the energy of interaction of an external field with the charge distribution is the same as with the superposed equivalent monopole and multipoles. Neither of these methods gives a physical picture of the equivalence of a charge distribution to the superposition of different multipoles. An attempt is made to interpret in physical terms the emergence of the multipoles of different order, that are equivalent to a charge distribution and to show that the magnitudes of the moments of these multipoles are in agreement with the results of both the approaches (a) and (b). This physical interpretation also helps to understand, in a simple manner, some of the wellknown properties of the multipole moments of atoms and nuclei. (K.B.)
Relativistic dynamics of point magnetic moment
Energy Technology Data Exchange (ETDEWEB)
Rafelski, Johann; Formanek, Martin; Steinmetz, Andrew [The University of Arizona, Department of Physics, Tucson, AZ (United States)
2018-01-15
The covariant motion of a classical point particle with magnetic moment in the presence of (external) electromagnetic fields is revisited. We are interested in understanding extensions to the Lorentz force involving point particle magnetic moment (Stern-Gerlach force) and how the spin precession dynamics is modified for consistency. We introduce spin as a classical particle property inherent to Poincare symmetry of space-time. We propose a covariant formulation of the magnetic force based on a 'magnetic' 4-potential and show how the point particle magnetic moment relates to the Amperian (current loop) and Gilbertian (magnetic monopole) descriptions. We show that covariant spin precession lacks a unique form and discuss the connection to g - 2 anomaly. We consider the variational action principle and find that a consistent extension of the Lorentz force to include magnetic spin force is not straightforward. We look at non-covariant particle dynamics, and present a short introduction to the dynamics of (neutral) particles hit by a laser pulse of arbitrary shape. (orig.)
The Anomalous Magnetic Moment of the Muon
Jegerlehner, Friedrich
2008-01-01
This book reviews the present state of knowledge of the anomalous magnetic moment a=(g-2)/2 of the muon. The muon anomalous magnetic moment amy is one of the most precisely measured quantities in elementary particle physics and provides one of the most stringent tests of relativistic quantum field theory as a fundamental theoretical framework. It allows for an extremely precise check of the standard model of elementary particles and of its limitations. Recent experiments at the Brookhaven National Laboratory now reach the unbelievable precision of 0.5 parts per million, improving the accuracy of previous g-2 experiments at CERN by a factor of 14. A major part of the book is devoted to the theory of the anomalous magnetic moment and to estimates of the theoretical uncertainties. Quantum electrodynamics and electroweak and hadronic effects are reviewed. Since non-perturbative hadronic effects play a key role for the precision test, their evaluation is described in detail. After the overview of theory, the exper...
The Koszul complex of a moment map
DEFF Research Database (Denmark)
Herbig, Hans-Christian; Schwarz, Gerald W.
2013-01-01
Let $K\\to\\U(V)$ be a unitary representation of the compact Lie group $K$. Then there is a canonical moment mapping $\\rho\\colon V\\to\\liek^*$. We have the Koszul complex ${\\mathcal K}(\\rho,\\mathcal C^\\infty(V))$ of the component functions $\\rho_1,\\dots,\\rho_k$ of $\\rho$. Let $G=K_\\C$, the complexif......Let $K\\to\\U(V)$ be a unitary representation of the compact Lie group $K$. Then there is a canonical moment mapping $\\rho\\colon V\\to\\liek^*$. We have the Koszul complex ${\\mathcal K}(\\rho,\\mathcal C^\\infty(V))$ of the component functions $\\rho_1,\\dots,\\rho_k$ of $\\rho$. Let $G......$ be a moment mapping and consider the Koszul complex given by the component functions of $\\rho$. We show that the Koszul complex is a resolution of the smooth functions on $Z=\\rho\\inv(0)$ if and only if the complexification of each symplectic slice representation at a point of $Z$ is $1$-large....
International Nuclear Information System (INIS)
Avishai, Y.; Fabre de la Ripelle, M.
1987-01-01
The contribution of CP violating nucleon-nucleon interaction to the electric dipole moment of 3 He is evaluated following a recent proposal for its experimental detection. Two models of CP violating interactions are used, namely, the Kobayashi-Maskawa mechanism and the occurrence of the Θ term in the QCD lagrangian. These CP violating interactions are combined with realistic strong nucleon-nucleon interactions to induce a CP forbidden component of the 3 He wave function. The matrix element of the electric dipole operator is then evaluated between CP allowed and CP forbidden components yielding the observable electric dipole moment. Using the parameters emerging from the penguin terms in the Kobaysashi-Maskawa model we obtain a result much larger than the electric dipole moment of the neutron in the same model. On the other hand, no enhancement is found for the Θ-term mechanism. A possible explanation for this difference is discussed. Numerical estimates can be given only in the Kobayashi-Maskawa model, giving d( 3 He) ≅ 10 30 e . cm. In the second mechanism, the estimate give d ( 3 He) ≅ 10 16 anti Θ. (orig.)
Local electric dipole moments: A generalized approach.
Groß, Lynn; Herrmann, Carmen
2016-09-30
We present an approach for calculating local electric dipole moments for fragments of molecular or supramolecular systems. This is important for understanding chemical gating and solvent effects in nanoelectronics, atomic force microscopy, and intensities in infrared spectroscopy. Owing to the nonzero partial charge of most fragments, "naively" defined local dipole moments are origin-dependent. Inspired by previous work based on Bader's atoms-in-molecules (AIM) partitioning, we derive a definition of fragment dipole moments which achieves origin-independence by relying on internal reference points. Instead of bond critical points (BCPs) as in existing approaches, we use as few reference points as possible, which are located between the fragment and the remainder(s) of the system and may be chosen based on chemical intuition. This allows our approach to be used with AIM implementations that circumvent the calculation of critical points for reasons of computational efficiency, for cases where no BCPs are found due to large interfragment distances, and with local partitioning schemes other than AIM which do not provide BCPs. It is applicable to both covalently and noncovalently bound systems. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
International Nuclear Information System (INIS)
Hosoya, Shinichi; Yamashita, Tadashi; Iwatsuki, Teruki; Saegusa, Hiromitsu; Onoe, Hironori; Ishibashi, Masayuki
2016-01-01
The Mizunami Underground Research Laboratory (MIU) project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of geological disposal technologies through investigations of the deep geological environment in the crystalline host rock (granite) at Mizunami City in Gifu Prefecture, central Japan. On the occasion of the reform of the entire JAEA organization in 2014, JAEA identified the critical issues on the geoscientific research program: “Development of modelling technologies for mass transport”, “Development of drift backfilling technologies” and “Development of technologies for reducing groundwater inflow”, based on the latest results of the synthesizing R and D. The purposes of the “Development of drift backfilling technologies” are to develop closure methodology and technology, and long-term monitoring technology, and to evaluate resilience of geological environment. In order to achieve the purposes, previous information from the case example of underground facility constructed in crystalline rock in Europe has been collected in this study. In particular, the boundary conditions for the closure, geological characteristics, technical specifications, and method of monitoring have been focused. The information on the international project regarding drift closure test and development of monitoring technologies has also been collected. In addition, interviews were conducted to Finnish and Swedish specialists who have experiences involving planning, construction management, monitoring, and safety assessment for the closure to obtain the technical knowledge. Based on the collected information, concept and point of attention, which are regarding drift closure testing, and planning, execution management and monitoring on the closure of MIU, have been specified. (author)
Containment closure time following the loss of shutdown cooling event of YGN Units 3 and 4
International Nuclear Information System (INIS)
Seul, Kwang Won; Bang, Young Seok; Kim, Hho Jung
1999-01-01
The YGN Units 3 and 4 plant conditions during shutdown operation were reviewed to identify the possible event scenarios following the loss of shutdown cooling (SDC) event. For the five cases of typical reactor coolant system (RCS) configurations under the worst event sequence, such as unavailable secondary cooling and no RCS inventory makeup, the thermal hydraulic analyses were performed using the RELAP5/MOS3.2 code to investigate the plant behavior following the event. The thermal hydraulic analyses include the estimation of time to boil, time to core uncovery, and time to core heat up to determine the containment closure time to prevent the uncontrolled release of fission products to atmosphere. The result indicates that the containment closure is recommended to be achieved within 42 minutes after the loss of SDC for the steam generator (SG) inlet plenum manway open case or the large cold leg open case under the worst event sequence. The containment closure time is significantly dependent on the elevation and size of the opening and the SG secondary water level condition. It is also found that the containment closure needs to be initiated before the boiling time to ensure the survivability of the workers in the containment. These results will provide using information to operators to cope with the loss of SDC event. (Author). 15 refs., 3 tabs., 7 figs
An approach for the design of closure bolts of spent fuel elements transportation packages
International Nuclear Information System (INIS)
Mattar Neto, Miguel; Miranda, Carlos A.J.; Fainer, Gerson
2009-01-01
The spent fuel elements transportation packages must be designed for severe conditions including significant fire and impact loads corresponding to hypothetical accident conditions. In general, these packages have large flat lids connected to cylindrical bodies by closure bolts that can be the weak link in the containment system. The bolted closure design depends on the geometrical characteristics of the flat lid and the cylindrical body, including their flanges, on the type of the gaskets and their dimensions, and on the number, strength, and tightness of the bolts. There are well established procedures for the closure bolts design used in pressure vessels and piping. They can not be used directly in the bolts design applied to transportation packages. Prior to the use of these procedures, it is necessary consider the differences in the main loads (pressure for the pressure vessels and piping and impact loads for the transportation packages) and in the geometry (large flat lids are not used in pressure vessels and piping). So, this paper presents an approach for the design of the closure bolts of spent fuel elements transportation packages considering the impact loads and the typical geometrical configuration of the transportation packages. (author)
International Nuclear Information System (INIS)
Barrou, A.; Prost, J.P.; Delidais, M.
1983-08-01
In order to avoid undesirable plastic response in PWR primary system components, tests were performed on 1/10 scale pipes and elbows made from AISI 316 austenitic stainless steel. L/D ratios were from 0.56 to 4.50 mm, arc angles of elbows were 30 0 , 45 0 , 60 0 and 90 0 . Pipes were subjected to bending moments at 3 internal pressure levels. They were tested to determine the mode of failure and served as a reference for elbows. Elbows were subjected to in-plane (closing and opening) and out-of-plane bending moments, at 3 pressure and 2 temperature levels. During these tests, loadings and displacements of components were monitored. Ovalisation of sections was measured regularly. The experimental plastic collapse moment corresponding to excessive deformation was compared to the maximum allowable moment under Design conditions. The experimental plastic instability moment considered as a limit for functional capability was compared to the maximum allowable moment for level C and D service limits
Functional roles of lower-limb joint moments while walking in water.
Miyoshi, Tasuku; Shirota, Takashi; Yamamoto, Shin-Ichiro; Nakazawa, Kimitaka; Akai, Masami
2005-02-01
To clarify the functional roles of lower-limb joint moments and their contribution to support and propulsion tasks while walking in water compared with that on land. Sixteen healthy, young subjects walked on land and in water at several different speeds with and without additional loads. Walking in water is a major rehabilitation therapy for patients with orthopedic disorders. However, the functional role of lower-limb joint moments while walking in water is still unclear. Kinematics, electromyographic activities in biceps femoris and gluteus maximums, and ground reaction forces were measured under the following conditions: walking on land and in water at a self-determined pace, slow walking on land, and fast walking in water with or without additional loads (8 kg). The hip, knee, and ankle joint moments were calculated by inverse dynamics. The contribution of the walking speed increased the hip extension moment, and the additional weight increased the ankle plantar flexion and knee extension moment. The major functional role was different in each lower-limb joint muscle. That of the muscle group in the ankle is to support the body against gravity, and that of the muscle group involved in hip extension is to contribute to propulsion. In addition, walking in water not only reduced the joint moments but also completely changed the inter-joint coordination. It is of value for clinicians to be aware that the greater the viscosity of water produces a greater load on the hip joint when fast walking in water.
The relationship between local and moment magnitude in Greece during the period 2008-2016
Konstantinou, K. I.; Melis, N. S.
2018-03-01
We perform a systematic comparison between local and moment magnitudes in Greece for the period 2008-2016 when both magnitudes have been determined using waveform data recorded by the Hellenic Unified Seismic Network (HUSN). Differences between the two magnitudes scales on average do not exceed ± 0.2 units as has been found in other regions worldwide. A recalculation of local magnitude using magnitude residuals for each HUSN station shows that station site conditions have very little influence on the difference between local and moment magnitude. It is therefore more likely that wave propagation effects and in rare cases, anomalous source properties are dominant factors in shaping this difference. General orthogonal regression is applied to the whole dataset and also to subsets covering different areas of Greece or different time period to calibrate the one magnitude scale against the other using a linear model. The resulting relationships differ very little, suggesting that there is no significant regional/temporal variation between local and moment magnitudes. While these relationships predict that local magnitude is very close to moment magnitude if both are determined using HUSN data, the comparison with Global CMT moment magnitude (with M w in the range 4.5-6.2) shows that it is larger than local magnitude by 0.18 units. These results are particularly important for converting local magnitudes to equivalent moment magnitudes and thus homogenize the Greek earthquake catalog.