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Sample records for mottelson-nilsson model

  1. On the relation between the interacting boson model of Arima and Iachello and the collective model of Bohr and Mottelson

    International Nuclear Information System (INIS)

    Assenbaum, H.J.; Weiguny, A.

    1982-01-01

    The generator coordinate method is used to relate the interacting boson model of Arima and Iachello and the collective model of Bohr and Mottelson through an isometric transformation. It associates complex parameters to the original boson operators whereas the ultimate collective variables are real. The absolute squares of the collective wave functions can be given a direct probability interpretation. The lowest order Bohr-Mottelson hamiltonian is obtained in the harmonic approximation to the interacting boson model; unharmonic coupling terms render the collective potential to be velocity-dependent. (orig.)

  2. A new relation of parameters of Bohr-Mottelson rotational spectra formula

    International Nuclear Information System (INIS)

    Li Mingliang; Xu Fuxin

    2003-01-01

    With the first three terms of Harris formula included and Mottelson's method followed, a new relation of the parameters of Bohr-Mottelson rotational spectra formula is brought forward. Superdeformed bands of even-even nuclei and normal deformed bands of nuclei in actinide and rare-earth are fitted with four-parameter Bohr-Mottelson rotational spectra formula. The relations of the parameters A, B, C, D are studied. The result show, for normal deformed bands, the new relation approach the experiment value in the same degree as the relation deduced from ab formula, but for superdeformed bands, the new relation is closer to the experiment than the relation deduced from ab formula. Three-parameter Harris formula may have better convergence than two-parameter Harris formula

  3. Assignment of Nilsson orbitals at superdeformation - identical bands

    Energy Technology Data Exchange (ETDEWEB)

    Ragnarsson, I [Lund Univ. (Sweden). Dept. of Mathematical Physics

    1992-08-01

    The relative transition energies of superdeformed rotational bands are used to extract ``effective alignments`` of the valence particles. It is found that the effective alignments give a direct picture of the Nilsson orbitals which are active in {sup 146-150}Gd, i.e., especially the orbitals [651 1/2] and [642 5/2], and that all bands observed in these nuclei can be understood within one consistent scheme. The experimental features are reproduced in calculations using the Nilsson-Strutinsky cranking model. The nearly identical transition energies seen in neighboring odd-proton and even-proton nuclei in the Dy/Tb/Gd region are investigated using the same formalism. Again, a consistent picture seems to emerge where, as suggested previously, the nucleus with a hole in the [301 1/2] Nilsson orbital and the corresponding core nucleus have calculated transition energies which are almost identical over a large range in spin. 2 refs., figs.

  4. E2 transition probabilities between Nilsson states in odd-A nuclei

    International Nuclear Information System (INIS)

    Krpic, D.K.; Savic, I.M.; Anicin, I.V.

    1976-01-01

    Presented here are the matrices needed for the calculation of E2 transition probabilities between all pairs of Nilsson states with ΔN = 0 and ΔK = 0, 1, 2. The needed coefficients of states are tabulated by Nilsson and by Davidson

  5. Identification of Nilsson orbitals in the superdeformed minimum of 237Pu

    International Nuclear Information System (INIS)

    Morgan, Thomas James

    2008-01-01

    In this thesis, a spectroscopy experiment in the second minimum of the double humped fission barrier of 237 Pu is presented, in which, for the first time, single - particle states for a neutron - rich shape isomer with odd neutron number were identified and characterised by their Nilsson quantum numbers. While rotational ( 236f U and 240f Pu) and vibrational excitations ( 240f Pu) had already been identified earlier in the even-even neighbouring nuclei, now the fission isomers in 237 Pu (t 1/2 =115 ns/1.12 μs) were investigated in a γ-spectroscopy experiment at the Cologne Tandem accelerator. Using the 235 U(α,2n) reaction with a pulsed R beam, states in the second minimum were populated. Following the prompt decay of excited states into the ground states of the two shape isomers, the nucleus decays with its halflife, the resulting fission fragments were detected in a specially built 4π parallel plate detector. The extremely rare isomeric γ decays were measured in coincidence with the fission fragments using the highly efficient MINIBALL spectrometer. The background-subtracted γ-ray spectrum was disentangled into contributions from the two shape isomers and 9 excited rotational bands were identified built on the ground states of the two isomers. The ground state spins of the two shape isomers were determined to be I=5/2 (115 ns isomer) and I=9/2 (1120 ns isomer). From the 149 identified γ transitions, independent level schemes were constructed for the two fission isomers in 237 Pu. The consistency of these level schemes was supported by the connecting γ transitions between rotational bands. Furthermore, both level schemes could be combined to a common level scheme, in which the ground state of the long-lived 9/2 isomer was placed 54.0(3) keV above the ground state of the short-lived 5/2 isomer. The resulting level scheme was compared to Hartree-Fock-Bogolyubov single-particle calculations, Nilsson model and Woods-Saxon potential calculations. This

  6. Identification of Nilsson orbitals in the superdeformed minimum of {sup 237}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Thomas James

    2008-03-31

    -particle calculations, Nilsson model and Woods-Saxon potential calculations. This comparison allowed for the first time an assignment of the Nilsson quantum numbers. In the course of this thesis the 5/2{sup +}[862] and 9/2{sup +}[624] Nilsson single-particle states were identified for the ground states of the two isomers in {sup 237f}Pu as well as 3/2{sup -}[512] and 7/2{sup -}[514] for excited rotational bands, for the first time based on calculations reproducing the deformed magic neutron number N=146. The identification of Nilsson orbitals will provide an important input for the validation and improvement of theoretical nuclear models and will lead to improved predictions for fission barriers and their extrapolations to neutron-rich heavy elements in the mass region of the r-process path of the astrophysical nucleosynthesis. (orig.)

  7. Inspirations from the theories of Bohr and Mottelson: a Canadian perspective

    International Nuclear Information System (INIS)

    Ward, D; Waddington, J C; Svensson, C E

    2016-01-01

    The theories developed by Bohr and Mottelson have inspired much of the world-wide experimental investigation into the structure of the atomic nucleus. On the occasion of the 40th anniversary of the awarding of their Nobel prize, we reflect on some of the experimental developments made in understanding the structure of nuclei. We have chosen to focus on experiments performed in Canada, or having strong ties to Canada, and the work included here spans virtually the whole of the second half of the 20th century. The 8π Spectrometer, which figures prominently in this story, was a novel departure for funding science in Canada that involved an intimate collaboration between a Crown Corporation (Atomic Energy of Canada Ltd) and University research, and enabled many of the insights discussed here. (invited comment)

  8. Radiation and penetration matrix elements for magnetic quadrupole transitions between Nilsson states in odd nuclei

    International Nuclear Information System (INIS)

    Feresin, A.P.; Guseva, I.S.

    1984-01-01

    Single-particle matrix elements for magnetic quadrupole gamma radiation in odd deformed nuclei, calculated with the aid of Nilsson-potential wave functions, are presented. Also given are the internal conversion penetration matrix elements, calculated in the same manner. The penetration matrix elements are needed to estimate the nuclear penetration parameter, which determines the deviation of experimental internal conversion coefficients from their standard values given in tables. Matrix elements are given for transitions between all pairs of Nilsson single-particle states with ΔN = 1 and ΔK = 0, 1, and 2 for the nuclear shells with 4< or =N< or =7 and for the two deformation values epsilon = 0.2 and 0.3

  9. Magnetic dipole moments of deformed odd-A nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Garg, V P; Sharma, S D; Mahesh, P S [Punjabi Univ., Patiala (India). Dept. of Physics

    1976-12-01

    Using an extended version of A S Davydov and G F Filippov's model (1958), B E Chi and J P Davidson have calculated magnetic moments of odd-A nuclei in 2s-ld shell, diagonalizing the state matrices for a set of parameters giving the best fit for nuclear spectra (1966). To study the failure of this model in case of nuclear moments, instead of diagonalizing an attempt has been made to simplify the expression for magnetic dipole moment for single nucleonic states without configuration mixing. The model takes care of the proper sign of spin projections. On replacing the total angular momentum j of odd particle (proton or neutron) by its projection ..cap omega.., the expression reduces to that of Mottelson and Nilsson for spin-up nuclei. The Coriolis coupling calculations also have been performed for those odd-A nuclei with K = 1/2. The results are found in better agreement with experimental report in comparison with those of other models.

  10. Probability theory plus noise: Replies to Crupi and Tentori (2016) and to Nilsson, Juslin, and Winman (2016).

    Science.gov (United States)

    Costello, Fintan; Watts, Paul

    2016-01-01

    A standard assumption in much of current psychology is that people do not reason about probability using the rules of probability theory but instead use various heuristics or "rules of thumb," which can produce systematic reasoning biases. In Costello and Watts (2014), we showed that a number of these biases can be explained by a model where people reason according to probability theory but are subject to random noise. More importantly, that model also predicted agreement with probability theory for certain expressions that cancel the effects of random noise: Experimental results strongly confirmed this prediction, showing that probabilistic reasoning is simultaneously systematically biased and "surprisingly rational." In their commentaries on that paper, both Crupi and Tentori (2016) and Nilsson, Juslin, and Winman (2016) point to various experimental results that, they suggest, our model cannot explain. In this reply, we show that our probability theory plus noise model can in fact explain every one of the results identified by these authors. This gives a degree of additional support to the view that people's probability judgments embody the rational rules of probability theory and that biases in those judgments can be explained as simply effects of random noise. (c) 2015 APA, all rights reserved).

  11. Remarks on the microscopic derivation of the collective model

    International Nuclear Information System (INIS)

    Toyoda, T.; Wildermuth, K.

    1984-01-01

    The rotational part of the phenomenological collective model of Bohr and Mottelson and others is derived microscopically, starting with the Schrodinger equation written in projection form and introducing a new set of 'relative Euler angles'. In order to derive the local Schrodinger equation of the collective model, it is assumed that the intrinsic wave functions give strong peaking properties to the overlapping kernels

  12. Una investigación fílmica en un laberinto literario: ‘El crimen de Oribe’ de Leopoldo Torre Nilsson (1950

    Directory of Open Access Journals (Sweden)

    Matthias Hausmann

    2016-08-01

    Full Text Available Comentando ciertas adaptaciones cinematográficas de obras literarias de Adolfo Bioy Casares el crítico de cine Sergio Wolf escribe: „[L]a narrativa del autor es en sí ‚una trampa para cineastas‘ aunque prometa ser ‚una trama para cineastas‘.“ Leopoldo Torre Nilsson no sólo rodó La mano en la trampa, sino fue también el primero en meter la mano en esa trampa que constituyen las narraciones de Bioy, porque su primer propio largometraje, El crimen de Oribe, basado en el cuento “El perjurio de la nieve”, es la primera transposición fílmica de una obra de su compatriota.En ese cuento Bioy construye un laberinto de declaraciones contradictorias sobre la misteriosa muerte de una joven muchacha, las cuales fuerzan al lector a hacer su propia investigación – una investigación que el autor quiere explícitamente literaria, porque para indicar pistas al lector hace comentar a sus personajes los manuscritos escritos por otros, lo que significa un desafío para cada adaptación fílmica. Nuestro artículo intenta mostrar cómo Torre reacciona ante este desafío; especial atención se presta a su tratamiento del motivo principal de la investigación así que al rol de un cosmos cerrado, tan importante en toda la obra de Torre Nilsson como en la de Bioy, y en otro procedimiento apreciado por el director y el autor a la vez, la mise en abyme.

  13. SU(6) quadrupole phonon model for even and odd nuclei and the SU(3) limit

    Energy Technology Data Exchange (ETDEWEB)

    Paar, V; Brant, S [Zagreb Univ. (Yugoslavia). Prirodoslovno Matematicki Fakultet; Canto, L F [Rio de Janeiro Univ. (Brazil). Inst. de Fisica; Leander, G [Lund Inst. of Tech. (Sweden). Dept. of Mathematical Physics; Oak Ridge National Lab., TN (USA)); Vouk, M [Zagreb Univ. (Yugoslavia). Computing Centre SRCE

    1982-04-05

    Analogous to the equivalence between the SU(6) quadrupole-phonon model (TQM) and the interacting boson model (IBM), the equivalence is pointed out for odd systems between the SU(6) particle quadrupole-phonon coupling model (PTQM) and the interacting boson-fermion model (IBFM). PTQM is formulated starting from the Dyson representation for the odd system. Different aspects of the SU(3) limit of TQM and PTQM are studied; the quadrupole-phonon block structure of rotational bands in even and odd nuclei and analytic expressions based on the coherent state; signature effects generated in PTQM; electromagnetic properties and correction factors for PTQM; overlaps of the PTQM analogs of Nilsson states with Coriolis-coupled Nilsson states and the relation to the rotational model representation.

  14. Structure of transition nuclei states in fermion dynamic-symmetry model

    International Nuclear Information System (INIS)

    Baktybaev, K.; Kojlyk, N.O.; Romankulov, K.

    2007-01-01

    In the paper collective structures of osmium heavy isotopes nucleons are studied. Results of diagonalization of SO(6) symmetric Hamiltonian of fermion-dynamical symmetry-model are comparing with results of other phenomenological methods such as Bohr-Mottelson model and interacting bosons model. For heavy osmium isotopes not only collective excitations spectral bands but also for probability of E2-electromagnet transition are which are compared with existing experimental data. It is revealed, that complexity of state structure for examined nuclei is related with competition and interweaving of rotation and vibration states and also more complicated states of γ instable nature

  15. Present status of the VMI and related models

    International Nuclear Information System (INIS)

    Scharff-Goldhaber, G.

    1980-05-01

    This article traces the evolution of the Variable Moment of Inertia model in its relation to the shell model, the Bohr-Mottelson model and the Interacting Boson Model. The discovery of a new type of spectrum, that of pseudomagic nuclei (isobars of doubly magic nuclei) is reported, and an explanation for their dynamics is suggested. The type of rotational motion underlying the ground state band of an e-e nucleus is shown to depend on whether the minimum number of valence nucleon pairs of one kind (neutrons or protons) is less than or equal to 2 or > 2. In the former case the alpha-dumbbell model holds; in the latter the two-fluid model

  16. Problems in nuclear wobbling motion

    International Nuclear Information System (INIS)

    Oi, Makito; Fletcher, Julian

    2005-01-01

    Experimental results in Lu isotopes in the A ∼ 160 mass region have been interpreted as indicating the existence of the wobbling mode proposed by Bohr and Mottelson. Despite the success analysing the obtained data by use of the phenomenological particle-plus-rotor model (PRM) by Hamamoto, questions still remain. These questions relate to the lack of evidence of even-even wobbling systems, the anharmonicity of the wobbling spectrum and the nonlinear spin dependence of the excitation energy. An extension of the original Bohr-Mottelson model is suggested that incorporates spin dependence into the moment of inertia which provides a possible mechanism for explaining the latter two questions, whilst phenomenological arguments are adopted for the first

  17. Algebraic formulation of collective models. I. The mass quadrupole collective model

    International Nuclear Information System (INIS)

    Rosensteel, G.; Rowe, D.J.

    1979-01-01

    This paper is the first in a series of three which together present a microscopic formulation of the Bohr--Mottelson (BM) collective model of the nucleus. In this article the mass quadrupole collective (MQC) model is defined and shown to be a generalization of the BM model. The MQC model eliminates the small oscillation assumption of BM and also yields the rotational and CM (3) submodels by holonomic constraints on the MQC configuration space. In addition, the MQC model is demonstrated to be an algebraic model, so that the state space of the MQC model carries an irrep of a Lie algebra of microscopic observables, the MQC algebra. An infinite class of new collective models is then given by the various inequivalent irreps of this algebra. A microscopic embedding of the BM model is achieved by decomposing the representation of the MQC algebra on many-particle state space into its irreducible components. In the second paper this decomposition is studied in detail. The third paper presents the symplectic model, which provides the realization of the collective model in the harmonic oscillator shell model

  18. Nobel prizes 1975

    International Nuclear Information System (INIS)

    Braunbek, W.

    1975-01-01

    The 1975 Nobel prize in physics was awarded to A. Bohr, B. Mottelson and J. Rainwater for their new ideas about the structure of the heavier atomic nuclei and the foundation of the 'unified model' of these nuclei. (orig.) [de

  19. Equivalence of the spherical and deformed shell-model approach to intruder states

    International Nuclear Information System (INIS)

    Heyde, K.; Coster, C. de; Ryckebusch, J.; Waroquier, M.

    1989-01-01

    We point out that the description of intruder states, incorporating particle-hole (p-h) excitation across a closed shell in the spherical shell model or a description starting from the Nilsson model are equivalent. We furthermore indicate that the major part of the nucleon-nucleon interaction, responsible for the low excitation energy of intruder states comes as a two-body proton-neutron quadrupole interaction in the spherical shell model. In the deformed shell model, quadrupole binding energy is gained mainly through the one-body part of the potential. (orig.)

  20. Experimental tests of recent nuclear models with the (n,γ) reaction

    International Nuclear Information System (INIS)

    Casten, R.F.

    1978-01-01

    The nonselectivity of the (n,γ) reaction provides a powerful tool for the study of those nuclear models of broad applicability whose characteristic excitations span a wide range of degrees of freedom. Several recent examples of this are discussed with particular emphasis on the recent discovery of the 0(6) limit of the interacting boson model and of a new interpretation of the Pt--0s transition region which consequently emerges. Other topics considered include recent extensions of the Nilsson model to new regions of nucleus, excitation energy and complexity of states. 43 references

  1. The SU(3) structure of rotational states in heavy deformed nuclei

    International Nuclear Information System (INIS)

    Jarrio, M.; Wood, J.L.; Rowe, D.J.

    1991-01-01

    The SU(3) coupling scheme provides an informative basis for the expansion of shell-model wave functions and their interpretation in collective-model terms. We show in this paper that it is possible, using the coupled-rotor-vibrator model, to infer averages of the distributions of SU(3) representation labels in heavy rotational nuclei by direct interpretation of physically observed E2 transition rates and quadrupole moments. We find that the distributions of SU(3) representation labels have nearly constant average values for states belonging to some well-defined rotational bands. These are bands of states having B(E2) values and quadrupole moments that follow the predictions of the rotor model. Such bands are interpreted as soft SU(3) bands in parallel with the concept of a soft rotor band with vibrational-shape fluctuations. The concept of a soft SU(3) band and its implications for beta-vibrational excited bands is developed. The average SU(3) representation labels inferred from experiment are interpreted by calculating those implied by the Nilsson model. An analysis of the SU(3) content of Nilsson wave functions also leads to two remarkable predictions. The first is that, in the asymptotic limit, the Nilsson model implies intrinsic states for a rotor band that are beta rigid. The second is that, although the intrinsic Nilsson state is axially symmetric, it generates a sequence of K=0, 2, 4,...bands. (orig.)

  2. Anharmonicity in nuclear wobbling motion

    International Nuclear Information System (INIS)

    Oi, M.

    2007-01-01

    An unexpected strong anharmonicity was observed in the wobbling spectrum in 163 Lu. In an attempt to understand what causes the deviation from the original wobbling model by Bohr and Mottelson, an analysis is presented using several different approaches, such as exact diagonalization, a semiclassical model to deal with anharmonic wobbling motion, and a microscopic method based on the self-consistent cranking calculation

  3. Coupled channel folding model description of α scattering from 9Be

    International Nuclear Information System (INIS)

    Roy, S.; Chatterjee, J.M.; Majumdar, H.; Datta, S.K.; Banerjee, S.R.; Chintalapudi, S.N.

    1995-01-01

    Alpha scattering from 9 Be at E α = 65 MeV is described in the coupled channel framework with phenomenological as well as folded potentials. The multipole components of the deformed density of 9 Be are derived from Nilsson model wave functions. Reasonably good agreements are obtained for the angular distributions of 3/2 - (g.s.) and 5/2 - (2.43 MeV) states of the ground state band with folded potentials. The deformation predicted by the model corroborates with that derived from the phenomenological analysis with potentials of different geometries

  4. Pseudo SU(3) shell model: Normal parity bands in odd-mass nuclei

    International Nuclear Information System (INIS)

    Vargas, C.E.; Hirsch, J.G.; Draayer, J.P.

    2000-01-01

    A pseudo shell SU(3) model description of normal parity bands in 159 Tb is presented. The Hamiltonian includes spherical Nilsson single-particle energies, the quadrupole-quadrupole and pairing interactions, as well as three rotor terms. A systematic parametrization is introduced, accompanied by a detailed discussion of the effect each term in the Hamiltonian has on the energy spectrum. Yrast and excited band wavefunctions are analyzed together with their B(E2) values

  5. The core-quasiparticle model for odd-odd nuclei and applications to candidates for gamma-ray lasers

    International Nuclear Information System (INIS)

    Strottman, D.D.

    1988-01-01

    A reliable estimate of the properties of isomers that may be viable candidates for a gamma-ray laser requires the use of the most accurate save functions possible. The majority of models that have been used to estimate the properties of isomers are applicable to only selected regions of the nuclear mass table. In particular, the Bohr-Mottelson model of odd-A and odd-odd nuclei will fail if the even-even core is not strongly deformed or if the deformations are changing strongly as a function of mass. This paper reports how the problem is overcome in a new core- quasiparticle model for odd-odd nuclei. The model introduces the pairing interaction ab initio; the odd-A states are mixtures of particle and hole states. The core may be soft towards deformation or axial asymmetry and may change rapidly as a function of mass. Thus, the model is ideally suited for application to the region of transitional nuclei such as the Te, La, and Os regions

  6. Unique parity states in 109Pd as a test of particle-rotor and IBFA models

    International Nuclear Information System (INIS)

    Casten, R.F.

    1980-01-01

    Calculations were performed for anti-aligned levels in 109 Pd. For a Nilsson model with pairing, variable moment of inertia, and Coriolis coupling, the favored levels were well reproduced, but the low-spin unfavored states exhibited serious disagreement with experiment results. Calculations with the IBFA were a significant improvement, in particular a regards the splitting of states of common spin. Comments on the source of this improvement are offered. 2 figures, 1 table

  7. New estimates of quadrupole deformation β of some nearly spherical even Mo nuclei

    International Nuclear Information System (INIS)

    Singh, Y.; Gupta, K.K.; Singh, M.; Bihari, Chhail; Varshney, A.K.; Gupta, D.K.

    2013-01-01

    The deformation parameter β and γ of the collective model of Bohr and Mottelson are basic descriptors of the nuclear equilibrium shape and structure. In recent past the sets of deformation parameters (β, γ) have been extracted from both level energies and E2 transition rates in even Xe, Ba and Ce nuclei and Hf, W, Os, Pt and Hg nuclei using rigid triaxial rotor model of Davydov – Filippov

  8. Two-body potentials in the collective model

    International Nuclear Information System (INIS)

    Draayer, J.P.; Rosensteel, G.; Arizona State Univ., Tempe

    1982-01-01

    The question, 'How well can a 1+2-body shell-model interaction represent a many-body potential.', is addressed by optimally expanding the (1+2+3)-body potential β 3 cos 3γ and the (1+2+3+4)-body potential β 4 of the Bohr-Mottelson collective model in terms of (1+2)-body operators. It is found that the correlation of β 4 with its approximation is greater than 97% throughout the sd shell. Although β 3 cos 3γ is also well approximated in the first half of the sd shell where it has more than 80% correlation with its approximation, the correlation drops abruptly at 28 Si to 50% and remains low in the second half of the shell. The approximations are primarily sums of the various components of the quadrupole-quadrupole interaction connecting different major oscillator shells. The results suggest that axially-symmetric deformation can be represented by simple (1+2)-body operators, whereas asymmetric shapes require non-simple 3-body terms. (orig.)

  9. Coupled channel folding model description of {alpha} scattering from {sup 9}Be

    Energy Technology Data Exchange (ETDEWEB)

    Roy, S.; Chatterjee, J.M.; Majumdar, H. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Calcutta 700064 (India); Datta, S.K. [Nuclear Science Centre, P.O.10502, New Delhi 110067 (India); Banerjee, S.R. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Calcutta 700064 (India); Chintalapudi, S.N. [Inter-University Consortium, Department of Atomic Energy Facilities, Bidhannagar, Calcutta 700064 (India)

    1995-09-01

    Alpha scattering from {sup 9}Be at {ital E}{sub {alpha}}= 65 MeV is described in the coupled channel framework with phenomenological as well as folded potentials. The multipole components of the deformed density of {sup 9}Be are derived from Nilsson model wave functions. Reasonably good agreements are obtained for the angular distributions of 3/2{sup {minus}}(g.s.) and 5/2{sup {minus}}(2.43 MeV) states of the ground state band with folded potentials. The deformation predicted by the model corroborates with that derived from the phenomenological analysis with potentials of different geometries.

  10. Odd - even staggering, a result of γ - band split

    International Nuclear Information System (INIS)

    Singh, M.; Gupta, D.K.; Singh, Yuvraj; Gupta, K.K.; Bihari, Chhail; Sharma, Aparna; Varshney, A.K.; Varshney, Mani

    2011-01-01

    The structure of low - lying K = 2+ gamma band in even - even nuclei represents quadrupole vibration breaking axial symmetry in unified collective model of Bohr-Mottelson. In the group theoretical approach of the Interacting boson model (IBM) the band structure can belong to one of the three limiting symmetries of U (6) algebra viz. U (5), SU (3) and O (6), corresponding to the anharmonic vibrator, deformed rotor and γ - unstable respectively

  11. Contribution to the projected Hartree-Fock method and microscopic theory of coupling between rotation bands

    International Nuclear Information System (INIS)

    Brut, F.

    1982-01-01

    The spectroscopy of odd-A nuclei, in the 1p and 2s-1d shells, is studied in the framework of the projected Hartree-Fock method and by the generator coordinate method. The nuclear effective interactions of Cohen and Kurath, on the one hand, and of Kuo or Preedom-Wildenthal, on the other hand, are used. The binding energies, the nuclear spectra, the static moments and the electromagnetic transitions obtained by these two approaches are compared to the same quantities given by a complete diagonalization in the shell model basis. This study of light nuclei gives some possibilities to put in order the energy levels by coupled rotational bands. In the microscopic approach, thus we find all the elements of the unified model of Bohr and Mottelson. To give evidence of such a relation, the functions of the angle β, in the integrals of the projection method of Peierls and Yoccoz, for a Slater determinant, are developed in the vicinity of the bounds β = O and β = π. The microscopic coefficients are evaluated in the Hartree-Fock approximation, using the particle-hole formalism. Calculations are made for 20 Ne and 21 Ne and the resulting microscopic coefficients are compared with the corresponding terms of the unified model of Bohr and Mottelson [fr

  12. A new model for nuclear matter

    International Nuclear Information System (INIS)

    Skyrme, T.H.R.

    1994-01-01

    The different values obtained for nuclear radii from electromagnetic interactions as compared with specifically nuclear interactions suggested a model of nuclear matter in which the meson field is supposed to condense into an incompressible fluid and the nucleonic sources are confined to its interior by a strong interaction between the sources and the fluid as a whole. The sources are also coupled to spin and charge fluctuations in the fluid, whose exchange leads to further internucleonic forces. It is necessary to postulate that the fluid have a comparatively low density; as a result rotational levels of the fluid are high, leading to a small probability of exchange of angular momentum (and charge coupled to it) with the sources. The values of the anomalous electrical interactions of nucleons deduced are in rough agreement with the facts. The nuclear structure indicated is a shell model embedded in the mesic fluid whose oscillations, strongly coupled to the nucleons, give rise to the collective features of nuclear structure as in the theory of Bohr and Mottelson. It is suggested that this picture of the mesic field may indicate where to look for solutions of the meson field equations. (author). 9 refs

  13. Shell model for warm rotating nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Matsuo, M.; Yoshida, K. [Kyoto Univ. (Japan); Dossing, T. [Univ. of Copenhagen (Denmark)] [and others

    1996-12-31

    Utilizing a shell model which combines the cranked Nilsson mean-field and the residual surface and volume delta two-body forces, the authors discuss the onset of rotational damping in normal- and super-deformed nuclei. Calculation for a typical normal deformed nucleus {sup 168}Yb indicates that the rotational damping sets in at around 0.8 MeV above the yrast line, and about 30 rotational bands of various length exists at a given rotational frequency, in overall agreement with experimental findings. It is predicted that the onset of rotational damping changes significantly in different superdeformed nuclei due to the variety of the shell gaps and single-particle orbits associated with the superdeformed mean-field.

  14. Strange history: the fall of Rome explained in Hereditas.

    Science.gov (United States)

    Bengtsson, Bengt O

    2014-12-01

    In 1921 Hereditas published an article on the fall of Rome written by the famous classical scholar Martin P:son Nilsson. Why was a paper on this unexpected topic printed in the newly founded journal? To Nilsson, the demise of the Roman Empire was explained by the "bastardization" occurring between "races" from different parts of the realm. Offspring from mixed couples were of a less stable "type" than their parents, due to the breaking up by recombination of the original hereditary dispositions, which led to a general loss of competence to rule and govern. Thus, the "hardness" of human genes, together with their recombination, was - according to Nilsson - the main cause of the fall of Rome. Nilsson's argument is not particularly convincingly presented. Human "races" are taken to have the same genetic structure as inbred crop strains, and Nilsson believes in a metaphysical unity between the individual and the race to which it belongs. However, in my view, Martin P:son Nilsson and his friend Herman Nilsson-Ehle had wider aims with the article than to explain a historical event. The article can be read as indicating strong support from the classical human sciences to the ambitious new science of genetics. Support is also transferred from genetics to the conservative worldview, where the immutability and inflexibility of the Mendelian genes are used to strengthen the wish for greater stability in politics and life. The strange article in Hereditas can, thus, be read as an early instance in the - still ongoing - tug-of-war between the conservative and the liberal ideological poles over how genetic results best are socially interpreted. © 2015 The Authors.

  15. Band mixing and electric monopole contribution in 2sub(. gamma. ). -->. 2sub(g) transition in /sup 168/Er

    Energy Technology Data Exchange (ETDEWEB)

    Sahota, H S; Hasiza, M L; Mittal, R [Punjabi Univ., Patiala (India). Dept. of Physics

    1976-06-01

    The 2sub(..gamma..)..-->..2sub(g) transition in /sup 168/Er has been examined for the presence of electric monopole contribution. The experimental E0/E2 reduced transition probabilities and monopole matrix element have been found to be somewhat larger than the theoretical predictions of the Bohr-Mottelson model but the ratio rhosup(2)/X has been found to agree well with the theoretical value. The band mixing parameters have also been evaluated and found to be sizeable.

  16. Chlorerede opløsningsmidler i den mættede zone

    DEFF Research Database (Denmark)

    Broholm, K.

    1996-01-01

    Anmeldelse af Jensen,B.K. & Nilsson,B.: Chlorerede opløsningsmidler i den mættede zone. Miljøstyrelsen 1996, (Miljøprojekt 330)......Anmeldelse af Jensen,B.K. & Nilsson,B.: Chlorerede opløsningsmidler i den mættede zone. Miljøstyrelsen 1996, (Miljøprojekt 330)...

  17. Most negative and most positive expectation values of the spin operator

    International Nuclear Information System (INIS)

    Zamick, Larry

    2011-01-01

    Formulas for the most positive and most negative values of the expectation of the spin operator are given and compared with single-particle values. The Nilsson model is used to evaluate these expectations and a scenario is discussed where the value is greater than one.

  18. Calculation of M1-excitations in the 42Ca, 44Ca and 54Fe with allowance for the 1p 1h * phonon configurations

    International Nuclear Information System (INIS)

    Kamerdzhiev, S.P.; Tkachev, V.N.

    1988-01-01

    The microscopic model of account of 1p1hx phonon configurations is used to describe M1-excitations in 42 Ca, 44 Ca and 54 Fe 1f 7/2 -shell. The most low-lying and more collectivized electrical phonons are taken into account. The Boron-Mottelson collective model with parameters obtained in the experiment is used to describe them. The calculation results are compared with calculations on other models. A set of all data allows to make the supposition that the deficient part of M1-resonance force in nuclei of 1f 7/2 -shell should be distributed on low-intensive 1 + -levels in the wide range of the nucleon binding energy

  19. The splitting of giant multipole states of deformed nuclei

    International Nuclear Information System (INIS)

    Suzuki, T.; Rowe, D.J.

    1977-01-01

    A vibrating potential model is applied to deformed nuclei with a deformed harmonic oscillator potential in order to discuss the splitting of isoscalar giant quadrupole states. Eigenfrequencies of the collective states are estimated to be √2ω(1 - delta/3), √2ω(1 - delta/6) and √2ω(1 + delta/3) for K = 0 + ,1 + and 2 + modes, respectively. The splitting of isovector dipole and isovector quadrupole states is also studied according to a schematic model as proposed by Bohr and Mottelson. It is shown that isovector dipole states are split, as in a hydrodynamic model, while isovector quadrupole states with the same scaling factors as those of isocalar quadrupole modes. (Auth.)

  20. An introduction to the interacting boson-fermion model

    International Nuclear Information System (INIS)

    Iachello, F.

    1985-01-01

    Spectra of odd-even medium mass and heavy nuclei are rather complex since they arise from the interplay between collective and single particle degrees of freedom. Their properties can be discussed in terms of simple models only in a limited number of cases, as, for example, in spherical nuclei (where the shell model can be applied in a straight forward way), or in nuclei with a rigid axially symmetric deformation (where the deformed shell model, or Nilsson model, can be used). Neither of these models, can, however, be applied to the large majority of nuclei, those forming the transitional classes. In the last few years, a model for odd-even nuclei has been introduced which is, on one side relatively simple, but which, on the other side, is able to describe the large variety of observed spectra. In this model, the collective degrees of freedom are described by bosons, while the single particle degrees of freedom are described by fermions, hence the name interacting boson-fermion model given to it. The authors describes the basic features of the model concentrating my attention to those cases that can be solved analytically, without resorting to numerical calculations. These analytical results are obtained by making use of group theory

  1. A deformable bag model of hadrons, 1

    International Nuclear Information System (INIS)

    Ui, Haruo; Saito, Koich

    1983-01-01

    As a generalization of the MIT spherical bag model, we construct the spheroidal bag model of hadron with an arbitrary eccentricity. This generalization is made by slightly modifying the MIT linear boundary condition: The linear boundary condition is examined in detail. Our model always satisfies two necessary requirements of the MIT bag model - i.e., n.j = 0, no quark colour flux leaves the bag, and q-barq = 0, the scalar density of quark should vanish on the bag surface- and it reduces to the MIT spherical bag model in the limit of zero-eccentricity. Lagrangian formalism of our model is briefly described. The eigenfrequencies of a single massless quark confined in this spheroidal bag are numerically calculated. We obtain the level-splitting of the excited quark orbits, which is just analogous to the well-known Nilsson's splitting of single particle orbits in deformed nuclei. By using the numerical results of the lowest orbit, the effect of the bag-deformation on the mass of low-lying hadrons is estimated. It is found that, although the spherical bag is stable, the quark bag is extremely soft against the quadrupole deformation. Brief discussions are added on the mechanisms which make the spherical bag more stable. (author)

  2. An approximate method for calculating the deformation of rotating nuclei

    International Nuclear Information System (INIS)

    Lind, P.

    1988-01-01

    The author presents as a collective model where the potential surface at spin I=0 is calculated in the Nilsson-Strutinsky model, an analytical expression for the moment of inertia is used which depends on the deformation and the pairing gaps for protons and neutrons, and the energy is minimized with respect to these gaps. Calculations in this model are performed for 16 Oyb. (HSI)

  3. Rotations as coherent states of SU(6) quadrupole phonons in the SU(3) limit

    Energy Technology Data Exchange (ETDEWEB)

    Canto, L F [Rio de Janeiro Univ. (Brazil). Inst. de Fisica; Paar, V [Zagreb Univ. (Yugoslavia). Prirodoslovno Matematicki Fakultet; Rio de Janeiro Univ. (Brazil). Inst. de Fisica)

    1981-06-18

    Analytic expressions for the wavefunctions of the ground-state rotational band for even and odd nuclei are derived in terms of spherical quadrupole phonons truncated at N(max) phonons. For N(max) ..-->.. infinite the Bohr-Mottelson rotational states are generated as an asymptotic gaussian distribution of quadrupole phonons.

  4. Low-energy coupling of individual and collective degrees of freedom: a general microscopic approach

    International Nuclear Information System (INIS)

    Quentin, P.; Meyer, M.

    1988-01-01

    A general microscopic approach of low energy coupling of individual and collective degrees of freedom is presented. The ingredients of a Bohr-Mottelson unified model description are determined consistently from the Skyrme SIII effective interaction, through the adiabatic limit of the time-dependent Hartree-Fock-Bogoliubov approximation. Three specific aspects will be mostly developed: i) the effect of pairing correlations on adiabatic mass parameters and collective dynamics; ii) a consistent coupling of collective and individual degrees of freedom to describe odd nuclei; iii) a study of spectroscopic data in odd-odd nuclei as a test of effective nucleon-nucleon interactions. (author)

  5. Reflections on collectivity

    International Nuclear Information System (INIS)

    Feshbach, H.

    1983-01-01

    Comments are made on papers presented to the International School of Nuclear Physics, Erice (1982) concerning collective bands and collectivity in nuclei. The importance of these collective modes of motion, the role of the Bohr-Mottelson model and the Interacting Boson Models (IBM-1 and IBM-2), and experimental evidence presented by a number of workers, are examined. The extensions of the models to take into account additional degrees of freedom both collective and non-collective, the discovery of new collective modes such as those corresponding to tri-axial shapes, and the possible existence of additional symmetries reported at the meeting, are discussed. Finally the importance is examined of relating the phenomenological models to a more fundamental underlying theory, which has been taken to be the nuclear shell model. (U.K.)

  6. Structure of the lowest excited 0/sup +/ rotational band of /sup 16/O

    Energy Technology Data Exchange (ETDEWEB)

    Ikebata, Yasuhiko; Suekane, Shota

    1983-10-01

    The structure of the lowest excited 0/sup +/ rotational band is investigated by using the extended Nilsson model wave functions with angular momentum projection and the B1 interaction, two-body LS-force of the Skyrme type and the Coulomb interaction. The results obtained show good agreement with energy interval in this band.

  7. Pramana – Journal of Physics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    ... of states max with a tendency for the system to become more oblate or prolate depending on the shift in the maximum density of states as the angular momentum decreases or increases. The change in nuclear level density with collectivity, i.e. with the use of cranked Nilsson model single particle levels has been noticed.

  8. Statistical model analysis of fast-neutron-induced fission of U isotopes

    International Nuclear Information System (INIS)

    Lestone, J.P.; Gavron, A.

    1994-01-01

    We have obtained the first experimental evidence of the washing out of the collective level density enhancement associated with the amma deformation of the triaxial first barrier in the U isotope cross sections at neutron energies up to ∼20 MeV, with a statistical model which uses level densities obtained from Nilsson model singles particle levels, we find that it is necessary to (1) wash out the triaxial level density enhancement at an excitation energy of ∼7 MeV above the triaxial barriers with a width of ∼1 MeV, and (2) incorporate the effects of preequilibrium emission. These results imply a γ deformation of the first barriers in the range 10 degree--20 degree. Above an incoming neutron energy of ∼20 MeV where insufficient data exist to constrain optical model potentials, our statistical model U(n,f) cross sections increasingly overestimate the experimental data. A satisfactory reproduction of all the available U(n,f) cross sections above ∼20 MeV is obtained by scaling our calculated compound nucleus formation cross sections. This scaling factor falls from 1.0 at ∼20 MeV to 0.82 at 100 MeV

  9. Calculation of nuclear moment of inertia with proper treatment of pairing interaction

    International Nuclear Information System (INIS)

    Tazaki, S.; Ando, Y.; Hasegawa, M.

    1997-01-01

    An attempt to calculate nuclear moments of inertia treating the pairing interaction exactly is reported. As usual, hamiltonian is composed of the Nilsson's singleparticle energies and the pairing interaction, but the eigenstates and the eigenvalues are calculated exactly in a realistic, sufficiently large model space. The method of calculating the moment of inertia is presented. (author)

  10. The τ-compression effect in γ-soft nulei

    International Nuclear Information System (INIS)

    Pan, X.W.; Feng, D.H.

    1993-01-01

    It is shown that a particular deviation from the SO(5) level structure persists in most well known SO(6)-like nuclei, namely, the τ-dependent compression of levels in the gamma-soft nuclei. This compression can be regarded as an extention of Mottelson-Valatin effect in the SO(5) scheme, i.e.. The reduction of pairing interaction with the increasing of τ-number will cause a compression in the energy levels. We find that this phenomenon can be effectively explained in terms of the SO(6) plus Pairing model. Using the pairing term to perturb the SO(6) Hamiltonian, a new level regularity for the SO(5) scheme is obtained

  11. Carbon Cowboys in Peru and the Prospects of Local REDD Governance

    Directory of Open Access Journals (Sweden)

    Wil de Jong

    2014-12-01

    Full Text Available The paper demonstrates the vulnerability of natural resource governance in locations where future forest carbon emission reduction will be pursued using payment mechanisms like REDD (Reducing Emission from Deforestation and Forest Degradation. The specific case is of an Australian national, David Nilsson who arrived in 2010 in the city of Iquitos, capital of the Peruvian Amazon. Nilsson tried to sign joint venture agreements with multiple indigenous organizations to trade carbon credits on their behalf. The paper analyses in much detail Nilsson's strategy to convince various local actors to sign up for his scheme. It demonstrates how people with responsibilities to represent indigenous interests, including leaders of their organizations, members of local NGos and staff of the regional government, eagerly supported these initiatives, but for ambiguous reasons. Even after Nilsson's treacherous dealings were widely exposed in the national and international news-media, this support did not stop. The case of this Peruvian carbon cowboy was specifically mentioned in "COICA's and AIDESEP's Iquitos Declaration", which is one of the early manifestations of an indigenous discourse that questions UNFCCC (United Nations Framework Convention on Climate Change and REDD (Reducing Emission from Deforestation and Forest Degradation. The paper demonstrates the political, institutional and governance fragility of locations where future REDD projects or similar initiatives to reduce forest carbon emissions are planned.

  12. Electromagnetic properties in {sup 160-170}Dy nuclei. A microscopic description by the pseudo-SU(3) shell model

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, Carlos E.; Bagatella-Flores, Norma [Universidad Veracruzana, Facultad de Fisica, Veracruz (Mexico); Velazquez, Victor [Universidad Nacional Autonoma de Mexico, Facultad de Ciencias, Mexico D.F. (Mexico); Lerma-Hernandez, Sergio [Universidad Veracruzana, Facultad de Fisica, Veracruz (Mexico); Universidad Nacional Autonoma de Mexico, Instituto de Ciencias Nucleares, Mexico D.F. (Mexico)

    2017-04-15

    The large collectivity observed in the rare-earth region of the nuclear landscape is well known. The microscopic studies are difficult to perform in this region due to the enormous size of the valence spaces, a problem that can be avoided by means of the use of symmetry-based models. Here we present calculations for electromagnetic properties of {sup 160-170}Dy nuclei within the pseudo-SU(3) scheme. The model Hamiltonian includes the preserving symmetry Q.Q term and the symmetry-breaking Nilsson and pairing terms, systematically parametrized for all members of the chain. The model is used to calculate B(E2) and B(M1) inter-band transition strengths between the ground state, γ and β-bands. In addition, we present results for quadrupole moments and g factors in these rotational bands. The results show that the pseudo-SU(3) shell model is a powerful microscopic theory for a description of electromagnetic properties of states in the normal parity sector in heavy deformed nuclei. (orig.)

  13. Hartree-Fock theory for the equilibrium shape of light nuclei; Theorie Hartree-Fock de la forme d'equilibre des noyaux legers

    Energy Technology Data Exchange (ETDEWEB)

    Ripka, G. [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires

    1968-09-01

    Most of the content of this thesis is published in english in Advances In Nuclear Physics, Vol. 1 (Editors: Baranger and Vogt - Plenum Press). The Hartree- Fock equations are derived. The expansions of the orbits and the possible symmetries of the Hartree-Fock field are discussed. Wavefunctions of even-even N = Z nuclei are given for 12 {<=} A {<=} 40. The role of the monopole, quadrupole and exchange components of the force are discussed. The multiplicity of the solutions and the effect of the spin-orbit interaction are discussed. Exact angular momentum projection is used to generate rotational bands. The validity of the adiabatic rotational model in light nuclei is discussed. Hartree-Fock calculations are extended to include major-shell mixing in order to obtain quadrupole deformations without the use of effective charge. The incompressibility, of nuclei is discussed and the compatibility between the Hartree-Fock solutions, the Mottelson model of quadrupole deformations and the SU3 states of J.P. Elliott and M. Moshinsky is established. (author) [French] La theorie de Hartree-Fock est appliquee au calcul des fonctions d'onde des noyaux legers deformes. Les equations de Hartree-Fock, les symetries permises et le choix du developpement des orbites sont discutes. Les fonctions d'onde des noyaux pair-pairs N = Z (12 {<=} A {<=} 40) sont tabulees. Les contributions des composantes monopolaires et quadrupolaires ainsi que des termes d'echange de la force nucleon-nucleon sont discutees. La methode de projection de moment cinetique est utilisee pour engendrer les bandes de rotation. La validite du modele rotationnel adiabatique est discutee. Les calculs de Hartree-Fock qui tiennent compte du melange de plusieurs couches majeures dans chaque orbite sont appliques au calcul des deformations quadrupolaires sans l'utilisation de charge effective. L'incompressibilite des noyaux et la compatibilite des fonctions d'onde de Hartree- Fock avec les

  14. Hartree-Fock theory for the equilibrium shape of light nuclei; Theorie Hartree-Fock de la forme d'equilibre des noyaux legers

    Energy Technology Data Exchange (ETDEWEB)

    Ripka, G [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires

    1968-09-01

    Most of the content of this thesis is published in english in Advances In Nuclear Physics, Vol. 1 (Editors: Baranger and Vogt - Plenum Press). The Hartree- Fock equations are derived. The expansions of the orbits and the possible symmetries of the Hartree-Fock field are discussed. Wavefunctions of even-even N = Z nuclei are given for 12 {<=} A {<=} 40. The role of the monopole, quadrupole and exchange components of the force are discussed. The multiplicity of the solutions and the effect of the spin-orbit interaction are discussed. Exact angular momentum projection is used to generate rotational bands. The validity of the adiabatic rotational model in light nuclei is discussed. Hartree-Fock calculations are extended to include major-shell mixing in order to obtain quadrupole deformations without the use of effective charge. The incompressibility, of nuclei is discussed and the compatibility between the Hartree-Fock solutions, the Mottelson model of quadrupole deformations and the SU3 states of J.P. Elliott and M. Moshinsky is established. (author) [French] La theorie de Hartree-Fock est appliquee au calcul des fonctions d'onde des noyaux legers deformes. Les equations de Hartree-Fock, les symetries permises et le choix du developpement des orbites sont discutes. Les fonctions d'onde des noyaux pair-pairs N = Z (12 {<=} A {<=} 40) sont tabulees. Les contributions des composantes monopolaires et quadrupolaires ainsi que des termes d'echange de la force nucleon-nucleon sont discutees. La methode de projection de moment cinetique est utilisee pour engendrer les bandes de rotation. La validite du modele rotationnel adiabatique est discutee. Les calculs de Hartree-Fock qui tiennent compte du melange de plusieurs couches majeures dans chaque orbite sont appliques au calcul des deformations quadrupolaires sans l'utilisation de charge effective. L'incompressibilite des noyaux et la compatibilite des fonctions d'onde de Hartree- Fock avec les fonctions d'onde SU3 de J

  15. Studies of internal bremsstrahlung spectrum of 35S beta emitter in the photon energy region of 1–100 keV

    International Nuclear Information System (INIS)

    Singh, Amrit; Dhaliwal, A.S.

    2014-01-01

    The internal bremsstrahlung (IB) spectral photon distribution, produced by soft beta particles of 35 S (W max =164 keV), in the photon energy region of 1–100 keV, is measured by using a Si(Li) detector, having high energy resolution and efficiency at low energy region. The measured spectral IB photon distribution is compared with KUB theory and Coulomb corrected IB theories given by Nilsson, and Lewis and Ford. After applying the necessary corrections, the experimental and theoretical IB spectral photon distributions are compared in terms of the number of IB photon of energy k per m o c 2 per unit photon yield. In the low energy region (below 10 keV), the experimental results are in agreement with all the theories. However, in photon energy region of 10–50 keV, experimental results are in agreement with Coulomb corrected Nilsson theory only, within the experimental errors. Further, beyond 50 keV, the Nilsson theory is more close to the experimental results than the KUB, and the Lewis and Ford theories. Hence, the Nilsson theory is more accurate than the other theories given by KUB and Lewis and Ford, particularly at a high energy end. The experimental results reported here with Si(Li) detector are free from number of ambiguities in earlier measurements reported with NaI(Tl) and HPGe detectors. The present results are indicating a relook into the theoretical considerations, given by different theories, while taking into account the Coulomb corrections for predicting the IB spectrum, particularly at high photon energy region. - Highlights: • The internal bremsstrahlung spectrum of 35 S beta emitter, in the photon energy region of 1–100 keV. • These measurement are taken by using a Si(Li) detector. • Theoretical and experimental results are reported in terms of number of photons of energy k per m 0 c 2 per unit photon yield. • The Nilsson theory for IB is more accurate than KUB and Lewis and Ford, particularly at high photon energy region

  16. Microscopic approach to nuclear anharmonicities

    International Nuclear Information System (INIS)

    Matsuo, Masayuki; Shimizu, Yoshifumi; Matsuyanagi, Kenichi

    1985-01-01

    Present status of microscopic study of nuclear anharmonicity phenomena is reviewed from the viewpoint of the time-dependent Hartree-Bogoliubov approach. Both classical- and quantum-mechanical aspects of this approach are discussed. The Bohr-Mottelson-type collective Hamiltonian for anharmonic gamma vibrations is microscopically derived by means of the self-consistent-collective-coordinate method, and applied to the problem of two-phonon states of 168 Er. (orig.)

  17. Theoretical study of band structure of odd-mass {sup 115,117}I isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Dhanvir, E-mail: singh1472phy@gmail.com; Kumar, Amit, E-mail: akbcw2@gmail.com; Sharma, Chetan, E-mail: chetan24101985@gmail.com [Research Scholar, Department of Physics and Electronics, University of Jammu, Jammu-180006 (India); Singh, Suram, E-mail: suramsingh@gmail.com [Assistant Professor, Department of Physics, Govt. Degree College, Kathua-184101 (India); Bharti, Arun, E-mail: arunbharti-2003@yahoo.co.in [Professor, Department of Physics and Electronics, University of Jammu, Jammu-180006 (India)

    2016-05-06

    By using the microscopic approach of Projected Shell Model (PSM), negative-parity band structures of odd mass neutron-rich {sup 115,117}I nuclei have been studied with the deformed single-particle states generated by the standard Nilsson potential. For these isotopes, the band structures have been analyzed in terms of quasi-particles configurations. The phenomenon of back bending in moment of inertia is also studied in the present work.

  18. Prediction of energies of yrast band in some even-even nuclei

    International Nuclear Information System (INIS)

    Varshney, A.K.; Singh, Yuvraj; Gupta, D.K.; Singh, M.; Gupta, K.K.; Bihari, Chhail; Dhiman, S.K.

    2012-01-01

    The deformation parameter β and γ of the collective model of Bohr and Mottelson are basic descriptors of the nuclear equilibrium shape and structure. The researchers found that the values of γ obtained from energies (= γ e ) are nearly equal to the value of γ derived from transition rate (= γ b ) in even Xe, Ba and Ce nuclei (A∼120-140) and Hf, W, Os, Pt and Hg nuclei (A∼160-200) using rigid triaxial rotor model of Davydov-Filippov. In the present study, the relatively light mass nuclei (Mo, Ru and Pd) have been taken. As far as γ is concerned, it is known that the Ru chains of nuclei is intermediate between the two having opposite trends for parameter γ, decreasing for Mo and increasing for Pd, and has an irregular behaviour in itself with the increase of neutron number

  19. Internal bremsstrahlung from 89Sr and 90Sr

    International Nuclear Information System (INIS)

    Sayibaba, T.; Narasimha Murity, K.; Rao, C.R.; Satyaprakash; Gubbi, G.K.

    1987-01-01

    The internal bremsstrahlung (IB) spectra emitted in the beta-decays of 89 Sr and 90 Sr were measured with a HPGe detector and a multichannel analyser along with a standard geometrical set-up. Sufficient care has been taken to avoid spurious effects. After making all the necessary corrections, the experimental results were compared with the corresponding theoretical distributions due to Knipp and Uhlenbeck and Bloch (KUB), Lewis and Ford, Nilsson, and also due to Ford and Martin (detour theory). The total IB yields of intensity and energy from each of the isotopes in the investigated energy regions are also determined and compared with the corresponding theoretical values. The present results of IB from 89 Sr are satisfactorily accounted for by the KUB theory. In the case of 90 Sr the experimental results of IB coincide with the Coulomb-corrected theoretical distibution due to Nilsson in the energy range from 60 keV to 110 keV and Beyond 110 keV, they are found to be in excess over Nilsson's theory as well as the detour theory due to Ford and Martin up to the maximum photon energy studied, namely 350 keV

  20. Evidensbaseret politikudvikling

    DEFF Research Database (Denmark)

    Vohnsen, Nina Holm

    2016-01-01

    within the civil services and from the research community (e.g. Boden & Epstein 2006; Cartwright et al. 2009; Elliott & Popay 2000; House of Commons 2006; Nilsson et al. 2008; Whitty 2006; Rod 2010, Vohnsen 2011). Some warn that the term ‘evidence-based’ is used too lightly, and often in cases where...... ‘evidence’ has not fed into the policy processes but rather has been invoked after the fact to support already agreed upon policy (House of Commons 2006; Nilsson et al. 2008); others warn that politics and science are – if not incompatible – then at odds with one another (e.g. Boden & Epstein 2006; Whitty...

  1. Internal bremsstrahlung accompanying non-unique second-forbidden β-decay of 36Cl

    International Nuclear Information System (INIS)

    Basha, A.M.; Khalil, E.I.; Hussein, M.; Ragab, H.S.; El-Konsol, S.

    1991-01-01

    The inner Bremsstrahlung spectrum (I.B.) associated with the non-unique second forbidden β-transition of 36 Cl was measured using a single channel NaI (Tl) scintillation spectrometer. After making all the necessary corrections, the experimental results were compared with the corresponding theoretical distributions due to the KUB, Lewis and Ford, Nilsson, Ford and Martin and Chang and Falkoff. Also a comparison with those calculated according to Nilsson theory after applying the shape correction factor (M. KUB) was done. The measured spectrum is found to show fairly good agreement with M. KUB theory and is found to deviate thereafter from all five theories. (orig.)

  2. How do nuclei really vibrate or rotate

    International Nuclear Information System (INIS)

    Andresen, H.G.; Kunz, J.; Mosel, U.; Mueller, M.; Schuh, A.; Wust, U.

    1983-01-01

    By means of the adiabatic cranking model the properties of the current and velocity fields of nuclear quadrupole vibrations for even-even nuclei in the rare-earth region are investigated. BCS correlated wave functions based on the Nilsson single particle Hamiltonian have been used. The current fields are analyzed in terms of vector spherical harmonics. The realistic microscopic currents show a vortex structure not present in the classical irrotational flow. The microscopic origin of the vortex structure is investigated

  3. High spin rotations of nuclei with the harmonic oscillator potential

    International Nuclear Information System (INIS)

    Cerkaski, M.; Szymanski, Z.

    1978-01-01

    Calculations of the nuclear properties at high angular momentum have been performed recently. They are based on the liquid drop model of a nucleus and/or on the assumption of the single particle shell structure of the nucleonic motion. The calculations are usually complicated and involve long computer codes. In this article we shall discuss general trends in fast rotating nuclei in the approximation of the harmonic oscillator potential. We shall see that using the Bohr Mottelson simplified version of the rigorous solution of Valatin one can perform a rather simple analysis of the rotational bands, structure of the yrast line, moments of inertia etc. in the rotating nucleus. While the precision fit to experimental data in actual nuclei is not the purpose of this paper, one can still hope to reach some general understanding within the model of the simple relations resulting in nuclei at high spin. (author)

  4. Measurement of the internal bremsstrahlung spectrum of a 89Sr beta emitter in the 1–100 keV photon energy regime

    International Nuclear Information System (INIS)

    Singh, Amrit; Dhaliwal, A.S.

    2015-01-01

    The internal bremsstrahlung (IB) spectrum of 89 Sr, which is a unique first forbidden beta emitter, is studied in the 1–100 keV photon energy regime. The IB spectrum is experimentally measured using a Si(Li) detector, which is efficient in this photon energy regime, and is compared with the IB distributions that are predicted by the Knipp, Uhlenbeck and Bloch (KUB), Nilsson, and Lewis and Ford theories. In the soft energy regime up to 15 keV, the measured results are in agreement with all the aforementioned theories. However, from 16–30 keV, the experimental results are in agreement with the Lewis and Ford theory, which applies to forbidden transitions, and at higher photon energies, the Nilsson theory best describes the measured results. The differences among the different theories also increase with the photon energy. The effect of the electrostatic Coulomb field on the IB process for beta emitters with different end-point energies is investigated by comparing the ratio of the IB probabilities predicted using the KUB and Nilsson theories for 35 S and 89 Sr, i.e., soft and hard beta emitters, respectively. The Coulomb effect is shown to be significant in the high photon energy regime and for beta emitters with low end-point energies. - Highlights: • Internal bremsstrahlung spectrum of 89 Sr, a unique first forbidden beta emitter, is studied. • The measurements are taken in the photon energy regions of 1–100 keV with Si(Li) detector. • The measured results are deviating from Lewis and Ford theory and are close to the Nilsson theory. • The effect of Coulomb field on the IB process for different end point energy sources is investigated. • Effect of Coulomb field is more for low energy beta emitter towards the high energy end

  5. Site investigation SFR. Water-rock interaction and mixing modelling in the SFR

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (University of Zaragoza (Spain))

    2011-10-15

    During 2008, the Swedish Nuclear Fuel and Waste Management Company (SKB) initiated an investigation programme for a future expansion of the final repository for low and medium level radioactive operational waste, SFR, located about 150 km north of Stockholm. The purpose of the investigations was to define and characterise a bedrock volume large enough to allow further storage of operational waste from existing Swedish nuclear power plants and future waste from the decommissioning and dismantling of nuclear power plant reactors (SKB 2008). Of several alternatives, a selected location was investigated southwest of the present SFR tunnel system. As part of the SFR Site Descriptive Model, the objective of the hydrogeochemical site description is to describe the chemistry, origin and distribution of groundwaters in the bedrock and the hydrogeochemical processes involved in their evolution. Hydrogeochemical information (salinity distribution, groundwater residence time, palaeohydrogeochemical input, etc.) are also of importance to help constrain the hydrogeological descriptive model. The hydrogeochemical modelling work has been performed in three steps, resulting in three model versions (0.1, 0.2 and 1.0). In versions 0.1 and 0.2, explorative analyses using traditional geochemical approaches (trend plots, x-y scatter plots, 3D visualisations, etc.) were performed to describe the data and to provide an early insight and understanding of the site. The final hydrogeochemical site description version 1.0 (Nilsson et al. 2011) includes data from the previous versions, as well as subsequent complementary data from the SFR extension project, and all these data are further evaluated using additional modelling approaches and techniques. In this context, the present report gives a more detailed analysis of the available data for some hydrogeochemical systems and a detailed description of the results of the geochemical and statistical modelling. One of the main aims is to establish

  6. Site investigation SFR. Water-rock interaction and mixing modelling in the SFR

    International Nuclear Information System (INIS)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia

    2011-10-01

    During 2008, the Swedish Nuclear Fuel and Waste Management Company (SKB) initiated an investigation programme for a future expansion of the final repository for low and medium level radioactive operational waste, SFR, located about 150 km north of Stockholm. The purpose of the investigations was to define and characterise a bedrock volume large enough to allow further storage of operational waste from existing Swedish nuclear power plants and future waste from the decommissioning and dismantling of nuclear power plant reactors (SKB 2008). Of several alternatives, a selected location was investigated southwest of the present SFR tunnel system. As part of the SFR Site Descriptive Model, the objective of the hydrogeochemical site description is to describe the chemistry, origin and distribution of groundwaters in the bedrock and the hydrogeochemical processes involved in their evolution. Hydrogeochemical information (salinity distribution, groundwater residence time, palaeohydrogeochemical input, etc.) are also of importance to help constrain the hydrogeological descriptive model. The hydrogeochemical modelling work has been performed in three steps, resulting in three model versions (0.1, 0.2 and 1.0). In versions 0.1 and 0.2, explorative analyses using traditional geochemical approaches (trend plots, x-y scatter plots, 3D visualisations, etc.) were performed to describe the data and to provide an early insight and understanding of the site. The final hydrogeochemical site description version 1.0 (Nilsson et al. 2011) includes data from the previous versions, as well as subsequent complementary data from the SFR extension project, and all these data are further evaluated using additional modelling approaches and techniques. In this context, the present report gives a more detailed analysis of the available data for some hydrogeochemical systems and a detailed description of the results of the geochemical and statistical modelling. One of the main aims is to establish

  7. My journey to the superheavy island with Szymanski, Nilsson, Nix, and Swiatecki from Lysekil to the present

    International Nuclear Information System (INIS)

    Mueller, Peter

    2010-01-01

    We discuss the great theoretical insights on nuclear stability that emerged in the late 1960s, especially the realization that observable nuclei might include a superheavy island 20+ protons beyond uranium with 92 protons. However, we now realize that the early models were not sufficiently quantitative to yield definite conclusions. Further groundwork for such models was laid in the 1970s. Around 1980 more quantitative, global and universal models appeared and together with experimental advances the mapping of the superheavy island, or as it turns out now, continent started in earnest. We review these early developments and conclude with some examples of our current insights. In particular, 1) some theoretical models do have predictive capabilities for nuclear properties such as ground-state masses, shapes, and half-lives 10 or more neutrons and protons away from previously known regions and 2) the superheavy island may be a continent connected to the actinides by a narrow land bridge; the continent itself may extend from about proton number Z = 110 to Z = 120 or slightly beyond. (author)

  8. Isomer-delayed gamma-ray spectroscopy of neutron-rich 166Tb

    Directory of Open Access Journals (Sweden)

    Gurgi L.A.

    2017-01-01

    Full Text Available This short paper presents the identification of a metastable, isomeric-state decay in the neutron-rich odd-odd, prolate-deformed nucleus 166Tb. The nucleus of interest was formed using the in-flight fission of a 345 MeV per nucleon 238U primary beam at the RIBF facility, RIKEN, Japan. Gamma-ray transitions decaying from the observed isomeric states in 166Tb were identified using the EURICA gamma-ray spectrometer, positioned at the final focus of the BigRIPS fragments separator. The current work identifies a single discrete gamma-ray transition of energy 119 keV which de-excites an isomeric state in 166Tb with a measured half-life of 3.5(4 μs. The multipolarity assignment for this transition is an electric dipole and is made on the basis internal conversion and decay lifetime arguments. Possible two quasi-particle Nilsson configurations for the initial and final states which are linked by this transition in 166Tb are made on the basis of comparison with Blocked BCS Nilsson calculations, with the predicted ground state configuration for this nucleus arising from the coupling of the v(1-/2[521] and π(3+/2 Nilsson orbitals.

  9. Internal bremsstrahlung spectral shapes of 45Ca and 35S

    International Nuclear Information System (INIS)

    Babu, R.P.; Murty, K.N.; Murty, V.A.N.

    1976-01-01

    The internal bremsstrahlung spectra emitted in the beta decays of 45 Ca and 35 S were measured using a multichannel NaI(Tl) scintillation spectrometer with a standard geometrical arrangement. After making all the necessary corrections, the experimental results were compared with the allowed theory of Knipp and Uhlenbeck (Physica; 3:425 (1936)) and of Bloch (Phys. Rev.; 50:272 (1936)) (KUB theory) and also with the Coulomb-corrected theories of Lewis and Ford (Phys. Rev.; 107:756 (1957)) and of Nilsson (Ark. Fys.; 10:467 (1956)). In the case of 45 Ca, fairly good agreement with KUB theory was obtained from 30 to 155 keV and above 155 keV the experimental results were in agreement with the Lewis and Ford theory up to 210 keV, the maximum limit of the photon energy investigated. For 35 S, the experimental results are in quite good agreement with KUB theory from 25 to 45 keV, but beyond 45 keV the values are greater than the Coulomb-corrected theories due to both Lewis and Ford and to Nilsson, the experimental excess over Nilsson Coulomb-corrected theory being by factors of 1.07, 1.12 and 1.63 at energies 60, 90 and 110 keV respectively. (author)

  10. Spin measurement for symmetric fission states of sup 24 Mg. A new angle on the sup 12 C+ sup 12 C interaction

    Energy Technology Data Exchange (ETDEWEB)

    Fulton, B.R.; Bennett, S.J.; Freer, M.; Murgatroyd, J.T. (School of Physics and Space Research, Birmingham Univ. (United Kingdom)); Gyapong, G.J.; Jarvis, N.S.; Jones, C.D.; Watson, D.L. (Dept. of Physics, York Univ. (United Kingdom)); Brown, J.D.; Rae, W.D.M.; Smith, A.E. (Dept. of Nuclear Physics, Oxford Univ. (United Kingdom)); Lilley, J.S. (Daresbury Lab., Warrington (United Kingdom))

    1991-09-19

    A new high resolution measurement of the {sup 12}C({sup 24}Mg, {sup 12}C{sup 12}C){sup 12}C breakup reaction has been performed. Sequential breakup is observed from specific states in {sup 24}Mg at excitation energies ranging from 20 to 26 MeV. Angular correlation measurements indicate that states with spins ranging from J=4 to 8 are populated. These states are consistent with superdeformed shape isomeric bands predicted by cranked cluster model and Nilsson-Strutinsky calculations. (orig.).

  11. Systematically too low values of the cranking model collective inertia parameters

    International Nuclear Information System (INIS)

    Dudek, I.; Dudek, W.; Lukasiak-Ruchowska, E.; Skalski, I.

    1980-01-01

    Deformed Nilsson and Woods-Saxon potentials were employed for generating single particle states used henceforth for calculating the inertia tensor (cranking model and monopole pairing) and the collective energy surfaces (Strutinsky method). The deformation was parametrized in terms of quadrupole and hexadecapole degrees of freedom. The classical energy expression obtained from the inertia tensor and energy surfaces was quantized and the resulting stationary Schroedinger equation was solved using the approximate method. The second Isup(π) = 0 + 2 collective level energies were calculated for the Rare Earth and Actinide nuclei and the results compared with the experimental data. The vibrational level energies agree with the experimental ones much better for spherical nuclei for both single particle potentials; the discrepancies for deformed nuclei overestimate the experimental results by roughly a factor of two. It is argued that coupling of the axially symmetric quadrupole degrees of freedom to non-axial and hexadecapole ones does not affect the conclusions about systematically too low mass parameter values. The alternative explanation of the systematic deviations from the 0 + 2 level energies could be a systematically too high stiffness of the energy surfaces obrained with the Strutinsky method. (orig.)

  12. Probability of production of internal bremmstrahlung from 99Tc radionuclei

    International Nuclear Information System (INIS)

    Ei-Konsol, S.; Gaafar, S.A.; Basha, A.M.; Hamed, A.A.

    1984-01-01

    The internal bremmstrahlung (IB) spectrum accompanying β-decay of 99 Tc (second forbidden β-transition) radionuclei has been measured using a single channel scintillation spectrometer. The measured IB spectrum was analyzed by the variable-width peeling-off method, and then corrected applying the proper corrections. This analyzed and corrected IB spectrum was compared with those calculated according to the original theories of Knipp and Uhlenbeck as well as of Bloch, the Coulomb-corrected theories of Lewis and Ford and of Nilsson, and according to the theory of Fords and Martin. The shape correction factor suggested by Konopinski and Uhlenbeck on the Fermi modification. The experimental results are in good agreement, up to 220 keV, with Nilsson theory after applying the shape correction factor. (author)

  13. Jõulukuusest saab Stroomi rannas skulptuur / Malle Pajula

    Index Scriptorium Estoniae

    Pajula, Malle, 1971-

    2002-01-01

    Tuleskulptuuri seavad kokku rootsi kunstnikud Gunnar Carl Nilsson ja Ola Öhlin, kes Rootsis asutasid tuleskulptorite seltsi. Tuleskulptuure teevad ka eesti kunstnikud ja üliõpilased. Süüdatakse 14. jaanuaril

  14. Some aspects of reflection asymmetric deformations in nuclei

    International Nuclear Information System (INIS)

    Olanders, P.

    1984-10-01

    The nuclear shape in the intrinsic frame is studied using the Strutinsky method. Various potentials (Nilsson, folded Yukawa and Woods-Saxon) are used for the microscopic part, and the macroscopic part is described as a liquid drop with either a sharp or a smooth surface. Special attention is paid to the possibility of octupole deformed ground states. The consequences of octupole deformations for the rotational behaviour are investigated using the cranking model. It is particularly shown that octupole deformation may supress the backbending in some nuclei. (author)

  15. Beta-delayed proton emission in neutron-deficient lanthanide isotopes

    International Nuclear Information System (INIS)

    Wilmarth, P.A.

    1988-01-01

    Forty-two β-delayed proton precursors with 56≤Z≤71 and 63≤N≤83 were produced in heavy-ion reactions at the Lawrence Berkeley Laboratory SuperHILAC and their radioactive decay properties studied at the on-line mass separation facility OASIS. Twenty-five isotopes and eight delayed proton branches were identified for the first time. Delayed proton energy spectra and proton coincident γ-ray and x-ray spectra were measured for all precursors. In a few cases, proton branching ratios were also determined. The precursor mass numbers were determined by the separator, while the proton coincident x-ray energies provided unambiguous Z identifications. The proton coincident γ-ray intensities were used to extract final state branching ratios. Proton emission from ground and isomeric states was observed in many cases. The majority of the delayed proton spectra exhibited the smooth bell-shaped distribution expected for heavy mass precursors. The experimental results were compared to statistical model calculations using standard parameter sets. Calculations using Nilsson model/RPA β-strength functions were found to reproduce the spectral shapes and branching ratios better than calculations using either constant or gross theory β-strength functions. Precursor half-life predictions from the Nilsson model/RPA β-strength functions were also in better agreement with the measured half-lives than were gross theory predictions. The ratios of positron coincident proton intensities to total proton intensities were used to determine Q/sub EC/-B/sub p/ values for several precursors near N=82. The statistical model calculations were not able to reproduce the experimental results for N=81 precursors. 154 refs., 82 figs., 19 tabs

  16. Inner Bremsstrahlung accompanying the non-unique first forbidden β-decay of 141Ce

    International Nuclear Information System (INIS)

    Khalil, E.I.

    1993-01-01

    The inner Bremsstrahlung (I.B.) spectrum accompanying the β-decay of 141 Ce (non-unique first forbidden β-transition) was measured using a single channel scintillation spectrometer. The measured I.B. was analyzed by the variable width peeling-off method. This analyzed and corrected I.B. was compared with those calculated according to the original theories of Knipp and Uhlenbeck as well as of Bloch (KUB), the coulomb corrected theories of Lewis and Ford and of Nilsson, and according to detour-transition calculations of the Ford and Martin theory. Ths shape correction factor suggested by Konopinski and Uhlenbeck on the Fermi β-decay theory was applied to the calculated I.B. based on Nilsson's theory (modified KUB theory). The experimental results are in better agreement with the modified KUB theory than the other theories. (orig.)

  17. Nuclear rotational population patterns in heavy-ion scattering and transfer reactions

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, J O; Stoyer, M A [Lawrence Berkeley Lab., CA (USA); Canto, L F; Donangelo, R [Universidade Federal do Rio de Janeiro, RJ (Brazil); Ring, P [Technische Univ. Muenchen, Garching (Germany, F.R.). Fakultaet fuer Physik

    1991-05-01

    A model of {sup 239}Pu with decoupled neutron is used for theoretical calculations of rotational population patterns in heavy ion inelastic scattering and one-neutron transfer reactions. The system treated in {sup 90}Zr on {sup 239}Pu at the near-barrier energy of 500 MeV and backscattering angles of 180deg and 140deg. The influence of the complex nuclear optical potential is seen to be very strong, and the Nilsson wave function of the odd neutron produces a distinctive pattern in the transfer reaction. (orig.).

  18. Single-particle and collective excitations in Ni-63

    OpenAIRE

    Albers, M.; Zhu, S.; Janssens, R. V. F.; Gellanki, Jnaneswari; Ragnarsson, Ingemar; Alcorta, M.; Baugher, T.; Bertone, P. F.; Carpenter, M. P.; Chiara, C. J.; Chowdhury, P.; Deacon, A. N.; Gade, A.; DiGiovine, B.; Hoffman, C. R.

    2013-01-01

    A study of excited states in Ni-63 up to an excitation energy of 28 MeV and a probable spin of 57/2 was carried out with the Mg-26(Ca-48,2 alpha 3n gamma)Ni-63 reaction at beam energies between 275 and 320 MeV. Three collective bands, built upon states of single-particle character, were identified. For two of the three bands, the transition quadrupole moments were extracted, herewith quantifying the deformation at high spin. The results have been compared with shell-model and cranked Nilsson-...

  19. Transition Probabilities in the 1/2+(631) Band in {sup 235}U

    Energy Technology Data Exchange (ETDEWEB)

    Hoejeberg, M; Malmskog, S G

    1969-09-15

    Measurements of absolute transition probabilities in the rotational band built on the 1/2{sup +}(631) single particle state in {sup 235}U have been performed using delayed coincidence technique. The following half-lives were obtained: T{sub 1/2} (13.0 keV level) = (0.50 {+-} 0.03) nsec. T{sub 1/2} (51.7 k e V level) = (0.20 {+-} 0.02) nsec. From the deduced B(E2) and B(M1) values magnetic and electric parameters were determined which could be compared with predictions from the Nilsson model.

  20. The residual proton-neutron interaction and nuclear collectivity

    International Nuclear Information System (INIS)

    Casten, R.F.

    1990-01-01

    The essential role of the valence, residual p-n interaction in the development of collectivity, though long known in general terms, has recently become increasingly apparent. A brief review of the p-n interaction is given, including some very basic nuclear data that illustrate its effects and the phenomenological N p N n scheme and the P-factor. This is followed by a discussion of recent experimental extractions of p-n matrix elements throughout the periodic table and theoretical efforts to understand them, in terms of both Shell and Nilsson models. 20 refs., 13 figs

  1. Research on convergence of nuclear rotational spectra formula

    International Nuclear Information System (INIS)

    Chen Yongjing; Xu Fuxin

    2001-01-01

    The superdeformed bands in the A-190 region are systematically analyzed using four-parameter rotational spectra formula of Bohr-Mottelson's I(I + 1) expansion. The convergence of two-parameter ab formula is compared with that of three-parameter abc formula by four parameters A, B, C, D. The result shows that the four-parameter value relation does not support the theoretically expected values of ab and abc formulas, but comparatively the four-parameter value relation agrees with the theoretically expected value of ab formula better than that of abc formula

  2. Cluster configuration and super deformation in f-p shell nuclei

    International Nuclear Information System (INIS)

    Shanmugam, G.; Santhosh Kumar, S.; Chintalapudi, S.N.; Benjamin, G.A.

    1996-01-01

    The aim of this work was to perform three oxygen clusters calculation for excited 48 Cr, to do a Cranked Nilsson Strutinsky calculations for it and to compare the results so as to look for super deformations

  3. Plaadid / Immo Mihkelson

    Index Scriptorium Estoniae

    Mihkelson, Immo, 1959-

    2003-01-01

    Uutest plaatidest Pachora "Astereotypical", Lisa Stansfield "Biography", The Last Hombres "Redemption", "The Four Feathers", "Liisi Koikson", Paul Simon "On My Way, Don't Know, Where I-m Goin'", Lisa Nilsson "Samlade Sanger 1992-2003", Emma Shapplin "Etterna"

  4. Investigation of the influence of nuclear charge on the internal Bremsstrahlung accompanying the β-decay of 45Ca and 141Ce

    International Nuclear Information System (INIS)

    Khalil, E.I.; Basha, A.M.

    1995-01-01

    The internal Bremsstrahlung (IB) spectrum accompanying the allowed β-decay of 141 Ce was measured using NaI (TI) scintillation spectrometer. The corrected IB distribution was compared with the theories for allowed β-transition of Knipp and Uhlenbeck as well as of Bloch (KUB), Lewis and Ford and Nilsson. Further, for 141 Ce isotope the corrected IB distribution was compared with the Ford and Martin theory (for detour β-transition) and modified KUB theory (where the shape correction factor suggested by Konopinski and Uhlenbeck on the Fermi β-decay theory was applied to the calculated IB based on Nilsson theory). This comparison between experiment and theory, and between the measurements of the two isotopes reflects the role played by the nuclear charge and the degree of forbiddenness on the IB spectrum. (author). 26 refs., 5 figs., 1 tab

  5. CryoSat-2 Processing and Model Interpretation of Greenland Ice Sheet Volume Changes

    Science.gov (United States)

    Nilsson, J.; Gardner, A. S.; Sandberg Sorensen, L.

    2015-12-01

    CryoSat-2 was launched in late 2010 tasked with monitoring the changes of the Earth's land and sea ice. It carries a novel radar altimeter allowing the satellite to monitor changes in highly complex terrain, such as smaller ice caps, glaciers and the marginal areas of the ice sheets. Here we present on the development and validation of an independent elevation retrieval processing chain and respective elevation changes based on ESA's L1B data. Overall we find large improvement in both accuracy and precision over Greenland relative to ESA's L2 product when comparing against both airborne data and crossover analysis. The seasonal component and spatial sampling of the surface elevation changes where also compared against ICESat derived changes from 2003-2009. The comparison showed good agreement between the to product on a local scale. However, a global sampling bias was detected in the seasonal signal due to the clustering of CryoSat-2 data in higher elevation areas. The retrieval processing chain presented here does not correct for changes in surface scattering conditions and appears to be insensitive to the 2012 melt event (Nilsson et al., 2015). This in contrast to the elevation changes derived from ESA's L2 elevation product, which where found to be sensitive to the effects of the melt event. The positive elevation bias created by the event introduced a discrepancy between the two products with a magnitude of roughly 90 km3/year. This difference can directly be attributed to the differences in retracking procedure pointing to the importance of the retracking of the radar waveforms for altimetric volume change studies. Greenland 2012 melt event effects on CryoSat-2 radar altimetry./ Nilsson, Johan; Vallelonga, Paul Travis; Simonsen, Sebastian Bjerregaard; Sørensen, Louise Sandberg; Forsberg, René; Dahl-Jensen, Dorthe; Hirabayashi, Motohiro; Goto-Azuma, Kumiko; Hvidberg, Christine S.; Kjær, Helle A.; Satow, Kazuhide.

  6. Evaluation of E2 form factor = 24Mg

    International Nuclear Information System (INIS)

    Marinelli, J.R.; Moreira, J.R.

    1988-11-01

    Longitudinal and transverse electron scattering form factors for the 2 + state at 1.37 Mev of the 24 Mg nucleus was evaluated with rotational model wavefunctions. Four different approaches were used for the transverse E2 form factor: PHF, cranking model, ridig rotor and irrotational flow. For the nuclear intrinsic wavefunction, the Nilsson model was assumed in all approaches yielding the calculation of the form factor in PWBA and DWBA. The results are discussed and compared with a recent measurement performed with 180 0 electron scattered from this state. The DWBA calculation, taking into account first order corrections shows that PHF and irrotational flow models give the best agreements with the available data and compete in quality with more complex calculation performed under the 'shell model' approach. (author) [pt

  7. Contribution to the study of deformed heavy nuclei by means of nuclear reactions; Contribution a l'etude des noyaux lourds deformes au moyen de reactions nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Gastebois, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-06-01

    The experimental results obtained in the study of the (d,p) reactions, at E{sub d} = 12 MeV, on the three even-even deformed nuclei {sup 170}Yb, {sup 172}Yb and {sup 174}Yb have been analysed in terms of DWBA calculations. The spectroscopic information relative to the odd final nuclei have been compared with the predictions of the collective model and of the Nilsson's model. The effect of various parameters used in the DWBA analysis (form factors, optical wave functions) has been carefully studied. The observed differences between the three final nuclei are qualitatively reproduced in the experimental study of resonances, seen in excitation functions of elastically and inelastically scattered protons on the same target nuclei, and corresponding to analogue states in the three nuclei {sup 171}Lu, {sup 173}Lu and {sup 175}Lu. (author) [French] Les resultats experimentaux de l'etude des reactions (d.p) a E{sub d} = 12 MeV, sur les noyaux deformes pairs-pairs {sup 170}Yb, {sup 172}Yb et {sup 174}Yb ont ete interpretes dans le cadre de l'approximation de Born des ondes deformees. Les informations spectroscopiques relatives aux noyaux impairs finals ont ete comparees aux predictions du modele collectif et du modele de Nilsson, apres avoir examine avec soin l'influence des differents parametres (facteurs de forme, fonctions d'onde 'optiques') utilises lors de l'analyse. Les differences observees entre les trois noyaux finals sont qualitativement reproduites par les resultats experimentaux de l'etude de resonances dans les fonctions d'excitation de diffusion elastique et inelastique de protons sur les memes noyaux-cibles, lors de la recherche d'etats analogues dans les noyaux {sup 171}Lu, {sup 173}Lu et {sup 175}Lu. (auteur)

  8. Training Level, Acculturation, Role Ambiguity, and Multicultural Discussions in Training and Supervising International Counseling Students in the United States

    Science.gov (United States)

    Ng, Kok-Mun; Smith, Shannon D.

    2012-01-01

    This research partially replicated Nilsson and Anderson's "Professional Psychology: Research and Practice" (2004) study on training and supervising international students. It investigated the relationships among international counseling students' training level, acculturation, supervisory working alliance (SWA), counseling self-efficacy (COSE),…

  9. Beta decay is 151Pr into levels in 151Nd

    International Nuclear Information System (INIS)

    Shibata, Michihiro; Ikuta, Tomohiko; Taniguchi, Akihiro

    1994-01-01

    The β-decay of 59 151 Pr 92 to the levels in 60 151 Nd 91 has been studied from the fission products of 235 U using an on-line isotope separator (KUR-ISOL). Gamma-rays and conversion electrons have been measured. Conversion coefficients have been determined for the first time. The precise decay scheme is proposed up to 2430 keV. The newly observed 65 γ-rays and 16 levels are incorporated in it. The deduced level scheme of 151 Nd was compared to the calculated level scheme on the basis of the rotation-vibration coupling model with a Nilsson potential. Low-lying levels were well reproduced by this model. (author)

  10. Competition between pairing and quadrupole deformation in the yrast sequence of sup(150,152)Dy

    International Nuclear Information System (INIS)

    Aberg, S.

    1984-05-01

    The yrast spectra are investigated for the non-collective nuclei sup(150,152)Dy using the Nilsson-Strutinsky + blocked BCS model. The separate effects from the pairing force and the quadrupole force (deformation changes) are studied. It is found that the pairing force is most important in describing the yrast line up to Iproportional30, while the quadrupole force is most important for I> or approx.20. The calculated increase of the oblate deformation with increasing spin is explained as an antipairing effect when only valence nucleons are building the total spin and as a polarization effect when the core becomes excited. (orig.)

  11. Multiple superdeformed bands in sup 194 Hg and their dynamical moments of inertia

    Energy Technology Data Exchange (ETDEWEB)

    Riley, M.A.; Cullen, D.M.; Alderson, A.; Ali, I.; Fallon, P.; Forsyth, P.D.; Hanna, F.; Mullins, S.M.; Roberts, J.W.; Sharpey-Schafer, J.F.; Twin, P.J. (Liverpool Univ. (UK). Oliver Lodge Lab.); Poynter, R.; Wadsworth, R. (York Univ. (UK). Dept. of Physics); Bentley, M.A.; Bruce, A.M.; Simpson, J. (Science and Engineering Research Council, Daresbury (UK). Daresbury Lab.); Sletten, G. (Niels Bohr Inst., Roskilde (Denmark). Tandem Accelerator Lab.); Nazarewicz, W. (Liverpool Univ. (UK). Oliver Lodge Lab. Politechnika Warszawska (Poland). Inst. Fizyki); Bengtsson, T. (Lund Inst. of Tech. (Sweden). Dept. of Mathematical Physics); Wyss, R. (Manne Siegbahn Inst. of Physics, Stockholm (Sweden))

    1990-05-28

    Three superdeformed bands have been observed in {sup 194}Hg. The dynamical moment of inertia J{sup (2)} of all three bands is observed to increase by 30-40% over the frequency range {Dirac h}{omega}=0.1-0.4 MeV. This phenomena can be understood in terms of the gradual alignment of pairs of high-j intruder orbitals within the framework of the cranked Woods-Saxon and Nilsson models including pairing. The calculations together with the observed J{sup (2)} behaviour of the three bands indicate that pairing correlations in the superdeformed minimum are rather weak. (orig.).

  12. The Low Energy Level Structure of {sup 191}lr

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G; Berg, V [AB Atomenergi, Nykoeping (Sweden); [Inst. of Physics, U niv. of Stockholm (Sweden); Baecklin, A; Hedin, G [Inst. of Physics, Univ. of Upp sala (Sweden)

    1970-02-15

    The decay of {sup 191}Pt to {sup 191}Ir has been investigated using Ge(Li)-detectors and a double focusing beta spectrometer. 35 transitions were observed and most of them were placed in a level scheme. Special attention was given to the low energy level band structure. Several multipolarity mixing ratios were determined from L-subshell ratio measurements. Using the delayed coincidence technique the half-life of the 179.05 keV level was measured to 40 {+-} 12 psec. The low level decay properties are discussed in terms of the Nilsson model with the inclusion of Coriolis coupling.

  13. Så styrs Mälarenergi med hjälp av Balanserat Styrkort

    OpenAIRE

    Agestav, Amanda; Nilsson, Camilla

    2009-01-01

    Title:   Controlling Mälarenergi by Balanced Scorecard  Seminar date:  2009-01-16  Institution:   School of Sustainable Development of Society and Technology  Course:   Bachelor thesis 15hp  Authors:   Camilla Nilsson, Amanda Agestav  Advisor:   Ulla Pettersson  The main issues:                What does Mälarenergi's Balanced Scorecard look like? Which Balanced Scorecard perspectives are important to Mälarenergi? Is Balanced Scorecard a purposeful control model in order for the group manageme...

  14. Static and dynamic deformations of actinide nuclei

    International Nuclear Information System (INIS)

    Rozmej, P.

    1985-09-01

    The zero-point quadrupole-hexadecapole vibrations have been taken into account to calculate dynamical deformations for even-even actinide nuclei. The collective and intrinsic motions are separated according to the Born-Oppenheimer approximation. The collective Hamiltonian is constructed using the macroscopic-microscopic method in the potential energy part and the cranking model in the kinetic energy part. The BCS theory with a modified oscillator potential is applied to describe the intrinsic motion of nucleons. A new set of Nilsson potential parameters, which produces a much better description of the properties of light actinide nuclei, has also been found. (orig.)

  15. The I{delta}KI = 1, E1 Transitions in Odd-A isotopes of Tb and Eu

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G [AB Atomenergi, Nykoeping (Sweden); Marelius, A [Dept. of Physics, Univ. of Uppsala, Uppsala (Sweden); Wahlborn, S [Div. of Theoretical Physics, Royal Inst. of Technology, Stockholm (Sweden); [Research Inst. for Physics, Stockholm (Sweden)

    1967-04-15

    Life-time measurements have been performed for the 5/2{sup -} [532] intrinsic state in the Tb isotopes with A = 155, 157, 159, and 161. The rates of the {delta}K = 1 E1 transitions in these isotopes, as well as in {sup 153}Eu and {sup 155}Eu, are discussed. With the Nilsson model as a starting point, the effects of pairing correlations and Coriolis coupling are calculated. It is found that these effects are not sufficient to account for the essential features of the experimental results. It is suggested that dipole contributions arising through octupole excitations are of importance.

  16. Identicity in high-K three quasiparticle rotational bands: a theoretical approach

    International Nuclear Information System (INIS)

    Kaur, Harjeet; Singh, Pardeep; Malik, Sham S

    2015-01-01

    The systematics are studied for the identical band phenomenon in high-K three quasiparticle rotational bands. The identical rotational bands based on the same bandhead spin are analyzed on the basis of similarities in γ-ray energies, dynamic moment of inertia and kinematic moment of inertia in particular, which is a function of deformation degrees of freedom, pairing strengths and Nilsson orbitals in nuclei. It is established that a combined effect of all these parameters decides the identicity of the moment of inertia in high-K three quasiparticle rotational bands as the systematics are backed by the Tilted Axis Cranking model calculations. (paper)

  17. Triaxiality - recent progress in mass 160 region

    International Nuclear Information System (INIS)

    Ma Wenchao

    2010-01-01

    Triaxiality may affect various properties of the nucleus, such as the quasiparticle excitation energy, the relationship between signature partner bands, the electromagnetic decay strength between bands, etc. However, these effects can also be caused by other phenomena. On the other hand, quantized wobbling-phonon excitation, characterized by a sequence of rotational bands with increasing number of wobbling quanta, is a predicted mode uniquely related to triaxiality of nuclear shape [A. Bohr and B.R. Mottelson, Nuclear Structure, Vol. II, Benjamin, New York, 1975]. The search for experimental signatures of triaxial nuclear shapes has proven to be very challenging.

  18. The field treatment of the nuclear spectrum. Historical foundation and two contributions to its ensuing development

    International Nuclear Information System (INIS)

    Bes, Daniel R

    2016-01-01

    The highlights of the model which was developed during the 1950s at the Niels Bohr Institute, Copenhagen, under the leadership of Aage Bohr and Ben Mottelson, are described in this contribution. Subsequently, it is shown that the field concept—the fundamental tool of the unified model—is not only an intelligent guess to describe the difficult many-body nuclear system. By means of a systematic expansion of field-coupling effects, the nuclear field theory (NFT) accounts for the overcompleteness of the initial product basis and the overlooking of the Pauli principle acting between constituents of the basis. Eventually it leads to the exact solution of the nuclear many-body problem. The description in terms of fields involves another problem if the field violates a symmetry inherent to the initial problem. The solution is borrowed from the BRST treatments of gauge systems, in which the lost symmetry is replaced by a more powerful one. (invited comment)

  19. Collective motion in prolate γ-rigid nuclei within minimal length concept via a quantum perturbation method

    Science.gov (United States)

    Chabab, M.; El Batoul, A.; Lahbas, A.; Oulne, M.

    2018-05-01

    Based on the minimal length concept, inspired by Heisenberg algebra, a closed analytical formula is derived for the energy spectrum of the prolate γ-rigid Bohr-Mottelson Hamiltonian of nuclei, within a quantum perturbation method (QPM), by considering a scaled Davidson potential in β shape variable. In the resulting solution, called X(3)-D-ML, the ground state and the first β-band are all studied as a function of the free parameters. The fact of introducing the minimal length concept with a QPM makes the model very flexible and a powerful approach to describe nuclear collective excitations of a variety of vibrational-like nuclei. The introduction of scaling parameters in the Davidson potential enables us to get a physical minimum of this latter in comparison with previous works. The analysis of the corrected wave function, as well as the probability density distribution, shows that the minimal length parameter has a physical upper bound limit.

  20. The EUA Institutional Evaluation Programme: An Account of Institutional Best Practices

    Science.gov (United States)

    Rosa, Maria Joao; Cardoso, Sonia; Dias, Diana; Amaral, Alberto

    2011-01-01

    When evaluating the EUA Institutional Evaluation Programme (IEP), Nilsson "et al." emphasised the interest in creating a data bank on good practices derived from its reports that would contribute to disseminating examples of effective quality management practices and to supporting mutual learning among universities. In IEP, evaluated…

  1. On 165Ho level scheme

    International Nuclear Information System (INIS)

    Ardisson, Claire; Ardisson, Gerard.

    1976-01-01

    A 165 Ho level scheme was constructed which led to the interpretation of sixty γ rays belonging to the decay of 165 Dy. A new 702.9keV level was identified to be the 5/2 - member of the 1/2 ) 7541{ Nilsson orbit. )] [fr

  2. Bohr Hamiltonian with different mass parameters applied to band ...

    Indian Academy of Sciences (India)

    The band structure of the proton-odd nuclei 153,155Eu, built on Nilsson orbitals, is .... [6]. When m = 0, the angular momentum vector of the prolate core is .... For the relevant results, figures 1 and 2, it is meaningful to discuss the quality of cal-.

  3. Quantitative Risk - Phase 1

    Science.gov (United States)

    2013-09-03

    November 2002 29. Ward, D., “The Comic Guide To Improving Defense Acquisitions”, Department of Defense, 2012 30. Nilsson, P.,Ohlsson, E...Professional Education Program, 2002 UNCLASSIFIED Contract Number: H98230-08-D-0171 TO 0030, RT 040 Report No. SERC-2013-TR-040-2 Revised

  4. Favored neutron excitations in superdeformed Gd-147

    NARCIS (Netherlands)

    Theisen, C; Khadiri, N; Vivien, JP; Ragnarsson, J; Beausang, CW; Beck, FA; Belier, G; Byrski, T; Curien, D; deFrance, G; Disdier, D; Duchene, G; Finck, C; Flibotte, S; Gall, B; Haas, B; Hanine, H; Herskind, B; Kharraja, B; Merdinger, JC; Nourreddine, A; Nyako, BM; Perez, GE; Prevost, D; Stezowski, O; Rauch, I; Rigollet, C; Savajols, H; SharpeySchafer, J; Twin, PJ; Wei, L; Zuber, K

    1996-01-01

    Four new superdeformed (SD) bands have been observed in Gd-147 using the EUROGAM II spectrometer. By comparison with (146,148,149),Gd SD bands, we use the effective alignment to assign excited band configurations, with the support of the Nilsson-Strutinsky cranking formalism. The effect of the

  5. Induction and flow cytometry identification of mixoploidy through ...

    African Journals Online (AJOL)

    faten omezzine

    16436 Afr. J. Biotechnol. 1.8 and 2. ..... 29:35-40. Alberts B, Bray D, Lewis J, Raff M, Roberts K,Watson D (1994). ... Gu XF, Yang AF, Meng H, Zhang JR (2005). In vitro ... Punt W, Blackmore S, Nilsson S and Le Thomas A (1994). Glossary of.

  6. Acoustic Sensor Network Design for Position Estimation

    Science.gov (United States)

    2009-05-01

    A., Pollock, S., Netter, B., and Low, B. S. 2005. Anisogamy, expenditure of reproductive effort, and the optimality of having two sexes. Operations...Research 53, 3, 560–567. Evans, M., Hastings, N., and Peacock , B. 2000. Statistical distributions. Ed. Wiley & Sons. New York. Feeney, L. and Nilsson, M

  7. Absolute Transition Probabilities from the 453.1 keV Level in {sup 183}W

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G

    1966-10-15

    The half life of the 453.1 keV level in {sup 183}W has been measured by the delayed coincidence method to 18.4 {+-} 0.5 nsec. This determines twelve absolute M1 and E2 transition probabilities, out of which nine are K-forbidden. All transition probabilities are compared with the single particle estimate. The three K-allowed E2, {delta}K = 2 transition rates to the 1/2{sup -} (510) rotational band are furthermore compared with the Nilsson model. An attempt to give a quantitative explanation of the observed transition rates has been made by including the effects from admixtures into the single particle wave functions.

  8. Absolute Transition Probabilities from the 453.1 keV Level in 183W

    International Nuclear Information System (INIS)

    Malmskog, S.G.

    1966-10-01

    The half life of the 453.1 keV level in 183 W has been measured by the delayed coincidence method to 18.4 ± 0.5 nsec. This determines twelve absolute M1 and E2 transition probabilities, out of which nine are K-forbidden. All transition probabilities are compared with the single particle estimate. The three K-allowed E2, ΔK = 2 transition rates to the 1/2 - (510) rotational band are furthermore compared with the Nilsson model. An attempt to give a quantitative explanation of the observed transition rates has been made by including the effects from admixtures into the single particle wave functions

  9. The superdeformed isotope chains in the rare-earth region

    International Nuclear Information System (INIS)

    Dong Baoguo; Chen Yongshou; Jin Xingnan

    1990-01-01

    Self-consistent calculations with respect to ε 2 and γ based on the cranked Nilsson model were done systematically for the superdeformed rotational states of nuclei in the rare-earth region. The results indicate that there exist a number of super-deformed isotope chains with neutron number N = 80-86 and quadrupole deformation ε 2 0.5-0.6. The calculated minimum angular momentum at which the superdeformed state becomes yrast has an average value of 60 ℎ and increases as the number of neutron increases within the chain. The calculation of shell correction energy surface indicates that the contribution of the neutron system is mostly responsible for the super-deformation

  10. Level density of radioactive doubly-magic nucleus 56Ni

    International Nuclear Information System (INIS)

    Santhosh Kumar, S.; Rengaiyan, R.; Victor Babu, A.; Preetha, P.

    2012-01-01

    In this work the single particle energies are obtained by diagonalising the Nilsson Hamiltonian in the cylindrical basis and are generated up to N =11 shells for the isotopes of Ni from A = 48-70, emphasizing the three magic nuclei viz, 48 Ni, 56 Ni and 68 Ni. The statistical quantities like excitation energy, level density parameter and nuclear level density which play the important roles in the nuclear structure and nuclear reactions can be calculated theoretically by means of the Statistical or Partition function method. Hence the statistical model approach is followed to probe the dynamical properties of the nucleus in the microscopic level

  11. Laser spectroscopy of laser-desorbed gold isotopes

    International Nuclear Information System (INIS)

    Savard, G.; Crawford, J.E.; Lee, J.K.P.; Thekkadath, G.

    1990-01-01

    Changes in mean-square charge radius δ 2 >, and magnetic dipole moments μ I have been measured for a series of neutron-deficient gold isotopes between A=186 and 196, and for neutron-rich 198,199 Au, using the PILIS system on-line with the ISOCELE mass separator. These measurements confirm the existence of the shape transition between A=186 and 187. The measured μ I values have been compared with calculations using Nilsson, and symmetric-rotor-plus-quasiparticle models. The results are consistent with the interpretation that 186 Au is prolate, and that the heavier isotopes have oblate, or possibly triaxial deformation. (orig.)

  12. Multi-particle excitations in the superdeformed {sup 149}Gd nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Flibotte, S. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires]|[Department of Physics and Astronomy, McMaster, University, Hamilton ON L8S 4M1 (Canada)]|[AECL Research, Chalk River Laboratories, Chalk River ON K0J 1J0 (Canada); Hackman, G. [Department of Physics and Astronomy, McMaster, University, Hamilton ON L8S 4M1 (Canada); Ragnarsson, I. [Department of Mathematical Physics, Lund institute of Technology, Box 118 S-221, Lund (Sweden); Theisen, C. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Andrews, H.R. [AECL Research, Chalk River Laboratories, Chalk River ON K0J 1J0 (Canada); Ball, G.C. [AECL Research, Chalk River Laboratories, Chalk River ON K0J 1J0 (Canada); Beausang, C.W. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 3BX (United Kingdom); Beck, F.A. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Belier, G. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Bentley, M.A. [Staffordshire University, Stoke on Trent (United Kingdom); Byrski, T. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Curien, D. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; France, G. de [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Disdier, D. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Duchene, G. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Haas, B. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Haslip, D.S. [Department of Physics and Astronomy, McMaster, University, Hamilton ON L8S 4M1 (Canada); Janzen, V.P. [Department of Physics and Astronomy, McMaster, University, Hamilton ON L8S 4M1 (Canada)]|[AECL Research, Chalk River Laboratories, Chalk River ON K0J 1J0 (Canada); Jones, P.M. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 3BX (United Kingdom); Kharraja, B.

    1995-02-20

    Six rotational bands built on superdeformed intrinsic configurations have been observed in the {sup 149}Gd nucleus with the Eurogam spectrometer. Orbital configuration assignments have been suggested on the basis of their effective alignments calculated with the Nilsson-Strutinsky cranking model. Most of the excited bands have identical partners in neighboring nuclei including one case differing by four mass units. Measurements of feeding patterns indicate that the {sup 149}Gd yrast superdeformed band is fed over a wider range of angular momentum than other yrast superdeformed bands in this mass region whereas weaker excited bands in the same nucleus are populated in narrower spin windows. ((orig.))

  13. Geomorphic classification of rivers

    Science.gov (United States)

    J. M. Buffington; D. R. Montgomery

    2013-01-01

    Over the last several decades, environmental legislation and a growing awareness of historical human disturbance to rivers worldwide (Schumm, 1977; Collins et al., 2003; Surian and Rinaldi, 2003; Nilsson et al., 2005; Chin, 2006; Walter and Merritts, 2008) have fostered unprecedented collaboration among scientists, land managers, and stakeholders to better understand,...

  14. Quantitative Risk - Phases 1 & 2

    Science.gov (United States)

    2013-11-12

    No. 4, November 2002 29. Ward, D., “The Comic Guide To Improving Defense Acquisitions”, Department of Defense, 2012 30. Nilsson, P.,Ohlsson, E...Conference Professional Education Program, 2002 Contract Number: H98230-08-D-0171 TO 0030, RT 040 Report No. SERC-2013-TR-040-3 Volume I November

  15. Nuclear shapes: from earliest ideas to multiple shape coexisting structures

    International Nuclear Information System (INIS)

    Heyde, K; Wood, J L

    2016-01-01

    The concept of the atomic nucleus being characterized by an intrinsic property such as shape came as a result of high precision hyperfine studies in the field of atomic physics, which indicated a non-spherical nuclear charge distribution. Herein, we describe the various steps taken through ingenious experimentation and bold theoretical suggestions that mapped the way for later work in the early 50s by Aage Bohr, Ben Mottelson and James Rainwater. We lay out a long and winding road that marked, in the period of 50s to 70s, the way shell-model and collective-model concepts were reconciled. A rapid increase in both accelerator and detection methods (70s towards the early 2000s) opened new vistas into nuclear shapes, and their coexistence, in various regions of the nuclear mass table. Next, we outline a possible unified view of nuclear shapes: emphasizing decisive steps taken as well as questions remaining, next to the theoretical efforts that could result in an emerging understanding of nuclear shapes, building on the nucleus considered as a strongly interacting system of nucleons as the microscopic starting point. (invited comment)

  16. Soil respiration and its role in Russia's terrestrial C flux balance for the Kyoto baseline year

    International Nuclear Information System (INIS)

    Stolbovoi, Vladimir

    2003-01-01

    This study introduces a transparent, operational model of estimating soil respiration (SR) to meet the requirements of the Kyoto Protocol of the United Nation Framework Convention on Climate Change within a framework of full carbon accounting (Nilsson et al.; 2000). By applying this model, we are able to define SR for the Kyoto 1990 baseline year for Russia (3200 Tg C), and establish soil emission thresholds for any spatial units, e.g. vegetation zones and land-use patterns. This model is built upon a fundamental biogeochemical cycle and provides a scientific basis for carbon management. SR comprised about 74% of the photosynthetically assimilated carbon in 1990, with the remainder accounted for in several areas. The carbon flux balance is, therefore, found to be closed for Russia. Our findings suggest that incomplete accounting is the reason for missing carbon globally

  17. Browse Title Index

    African Journals Online (AJOL)

    Items 451 - 500 of 592 ... Vol 15, No 1 (2013), Safe injections and waste management at a Sub-Saharan regional hospital: a quantitative descriptive study, Abstract PDF. Elisabeth Darj, Josefine Nilsson, Andrea Barnabas Pembe, Miriam Urasa. Vol 7, No 3 (2005), Sampling mosquitoes with CDC light trap in rice field and ...

  18. Systematics of triaxial moment of inertia and deformation parameters (β, γ) in even-even nuclei of mass region A = 90-120

    International Nuclear Information System (INIS)

    Singh, Yuvraj; Gupta, D.K.; Singh, M.; Gupta, K.K.; Bihari, Chhail; Varshney, A.K.; Dhiman, S.K.

    2012-01-01

    The deformation parameter β and γ of the collective model of Bohr and Mottelson are basic descriptors of the nuclear equilibrium shape and structure. In recent past the sets of deformation parameters ((β, γ) have been extracted from both level energies and E2 transition rates in even Xe, Ba and Ce nuclei (A∼120-140) and Hf, W, Os, Pt and Hg nuclei (A∼160-200) using rigid triaxial rotor model of Davydov-Filippov (DF). Researcher have found that the values of β obtained separately from energy and transition rate (β e and β b respectively), though, are found almost equal in heavy mass region (A ∼160-200) but, not so in medium mass (A∼120-140) nuclei. This observation puts a question mark whether the ββ dependence of moment of inertia in hydrodynamic model is reliable. The purpose of the present work is to study a relatively lighter mass region (A∼90-120) where the gap between values of two sets of β may further increase. To improve the calculations for extracting β e , the use of Grodzins rule will be made along with uncertainties, since only through this rule the E2 1 + is related with β G (value of β for symmetric nucleus and evaluated using Grodzins rule)

  19. Probing the nuclear structure with heavy-ion reactions

    International Nuclear Information System (INIS)

    Broglia, R.A.

    1982-01-01

    Nuclei display distortions in both ordinary space and in gauge space. It is suggested that it is possible to learn about the spatial distribution of the Nilsson orbitals and about the change of the pairing gap with the rotational frequency through the analysis of one- and two-nucleon transfer reactions induced in heavy-ion collisions

  20. Knowledge Governance for Sustainable Development: A Review

    Directory of Open Access Journals (Sweden)

    Lorrae van Kerkhoff

    2014-03-01

    Full Text Available Sustainable development is a knowledge intensive process, but plagued by persistent concerns over our apparent inability to connect what we know with more sustainable practices and outcomes. While considerable attention has been given to ways we may better understand and enhance the knowledge-based processes that support the governance of social-­ecological systems, relatively few have examined the governance of knowledge itself. The institutions—rules and norms—that govern knowledge may shed light on the persistence of 'gaps' between knowledge and action. In this review I seek to answer the question: can interdisciplinary knowledge governance literature contribute to understanding and analysing the institutional knowledge-based dimensions of sustainable development? I present and analyse the concept of knowledge governance as it is emerging in a range of disciplines and practice areas, including private sector management literature and public regulation theory and practice. I then integrate the findings from this review into a model of sustainable development proposed by Nilsson et al. [1]. I show that knowledge governance (as a scale above knowledge management can inform Nilsson et al.'s three "nested" dimensions of sustainability: human wellbeing (through access to knowledge and freedom to exercise informed choice; resource-base management (though enhancing regulation and innovation and transitions from exclusive to inclusive knowledge systems; and global public goods (by balancing public and private interests and fostering global innovation systems. This review concludes by presenting a framework that places sustainable development in the context of broader socio-political struggles towards more open, inclusive knowledge systems.

  1. Structure of the semi-decoupled π 1/2[411] band in odd proton nucleus 169Ta

    International Nuclear Information System (INIS)

    Song Hai; Deng Fuguo; Shao Liqin; Zhou Hongyu; Sun Huibin; Lu Jingbin; Zhao Guangyi; Yin Lichang; Liu Yunzuo

    2003-01-01

    High spin states of the odd proton-nucleus 169 Ta have been populated in the reaction 155 Gd( 19 F, 5 n) with beam energies of 97 MeV. Rotational band based on d 3/2 proton 1/2[411] Nilsson state has been pushed up to 39/2 + in the α=1/2 decay sequence. Its signature partner, the α=-1/2 decay sequence with four link transitions has been established and 1/2[411] band in 169 Ta was reassigned to be a semi-decoupled band. The systematics of the signature splitting in the K=1/2 bands in the rear-earth region and the accidental degeneracy conclusion given by the angular projection shell model were discussed

  2. Study of the 21Ne Nuclear Structure by capture of thermal neutrons in natural neon

    International Nuclear Information System (INIS)

    Stopa, C.R.S.

    1979-01-01

    Energy levels of 21 Ne up to 6.76 MeV are studied by measuring the thermal neutron capture gama rays from natural neon. A Ge(Li) detector is used. Energies and intensities are measured relative to calibration lines of nitrogen. The Q-value and the cross section of the reaction 20 Ne(n,γ) 21 Ne are calculated. The proposed level scheme is discussed in terms of the Nilsson model, considering the coupling of one particle to the 20 Ne core. Coriolis coupling is taken into account for the three positive parity bands, K sup(π)=3/2 + , 1/2 + and 5/2 + . Measurements are made using the research reactor of the Instituto de Energia Atomica [pt

  3. Experimental nuclear level densities and γ-ray strength functions in Sc and V isotopes

    International Nuclear Information System (INIS)

    Larsen, A. C.; Guttormsen, M.; Ingebretsen, F.; Messelt, S.; Rekstad, J.; Siem, S.; Syed, N. U. H.; Chankova, R.; Loennroth, T.; Schiller, A.; Voinov, A.

    2008-01-01

    The nuclear physics group at the Oslo Cyclotron Laboratory has developed a method to extract nuclear level density and γ-ray strength function from first-generation γ-ray spectra. This method is applied on the nuclei 44,45 Sc and 50,51 V in this work. The experimental level densities of 44,45 Sc are compared to calculated level densities using a microscopic model based on BCS quasiparticles within the Nilsson level scheme. The γ-ray strength functions are also compared to theoretical expectations, showing an unexpected enhancement of the γ-ray strength for low γ energies (E γ ≤3 MeV) in all the isotopes studied here. The physical origin of this enhancement is not yet understood

  4. Collective excitations at low energy: microscopic study of rotation, vibration and their coupling in even-even nuclei; Excitations collectives a basse energie: Etude microscopique de la rotation, de la vibration et de leur couplage dans les noyaux pair-pairs

    Energy Technology Data Exchange (ETDEWEB)

    Deloncle, I.

    1989-10-23

    In this study we have built the quadrupolar collective Bohr Hamiltonian in a purely microscopic way by using an approximation of the time-dependant Hartree-Fock adiabatic approach. The purpose of this work was to obtain a quantitative description of the collective properties in the low energy range of intermediate and heavy nuclei by using a 2-body effective interaction of Skyrme-type. We consider low energy processes as dynamic regimes in which the collective movement is adiabatic when compared with modes associated to individual freedom. In the N-body solution we propose, we have assumed that: -) a mean field exists at any moment, -) some collective variables exist whose temporal variations include all the dynamics, and -) the collective movement is adiabatic. This work is a microscopic formulation and an efficient approach to resolve the Bohr and Mottelson unified model. Low energy spectra have been computed for 4 nuclei: Ge{sup 74}, Se{sup 76}, Cd{sup 110} and Pt{sup 186} and they agree well with experimental data.

  5. The g-factor of the K=25 isomer in sup 182 Os

    Energy Technology Data Exchange (ETDEWEB)

    Alderson, A.; Fallon, P.; Goldring, G.; Roberts, J.; Sharpey-Schafer, J.; Twin P. (Liverpool Univ. (UK). Oliver Lodge Lab.); Bentley, M.; Bruce, A. (Science and Engineering Research Council, Daresbury (UK). Daresbury Lab.); Broude, C. (Weizmann Inst. of Science, Rehovoth (Israel). Dept. of Nuclear Physics); Dafni, E. (Rochester Univ., NY (USA). Nuclear Structure Research Lab.); Hass, M. (Argonne National Lab. (USA)); Nyberg, J.; Sletten, G. (Niels Bohr Inst., Roskilde (Denmark))

    1989-09-28

    The g-factor of the K=I=25 isomer in {sup 182}Os has been measured by observing the angular precession of the decay {gamma}-ray angular distribution in an external magnetic field as g=+0.425(8). This result is compared with predictions based on experimental g-factors of single-particle Nilsson orbitals in this mass region. (orig.).

  6. Investigation of antimagnetic rotation in 100Pd

    International Nuclear Information System (INIS)

    Zhu, S.; Garg, U.; Afanasjev, A. V.; Frauendorf, S.; Kharraja, B.; Ghugre, S. S.; Chintalapudi, S. N.; Janssens, R. V. F.; Carpenter, M. P.; Kondev, F. G.

    2001-01-01

    High spin states have been studied in the nucleus 100 Pd with the aim of investigating the novel phenomenon of ''antimagnetic rotation.'' A cascade of four ''rotational-band-like'' transitions is proposed as corresponding to antimagnetic rotation, based on the observed spectroscopic properties and a comparison with calculations in the configuration-dependent cranked Nilsson-Strutinsky formalism

  7. Microscopic study of neutron-rich dysprosium isotopes

    International Nuclear Information System (INIS)

    Vargas, Carlos E.; Velazquez, Victor; Lerma, Sergio

    2013-01-01

    Microscopic studies in heavy nuclei are very scarce due to large valence spaces involved. This computational problem can be avoided by means of the use of symmetry-based models. Ground-state, γ and β bands, and their B(E2) transition strengths in 160-168 Dy isotopes, are studied in the framework of the pseudo-SU(3) model which includes the preserving symmetry Q . Q term and the symmetry-breaking Nilsson and pairing terms, systematically parametrized. Additionally, three rotor-like terms are considered, whose free parameters, fixed for all members of the chain, are used to fine tune the moment of inertia of rotational bands and the band head of γ and β bands. The model succesfully describes in a systematic way rotational features in these nuclei and allows to extrapolate toward the midshell nucleus 170 Dy. The results presented show that it is possible to study a full chain of isotopes or isotones in the region with the present model. (orig.)

  8. Microscopic study of neutron-rich dysprosium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, Carlos E. [Universidad Veracruzana, Facultad de Fisica e Inteligencia Artificial, Xalapa (Mexico); Universidad Nacional Autonoma de Mexico, Facultad de Ciencias, Apartado Postal 70-542, Mexico D.F. (Mexico); Velazquez, Victor [Universidad Nacional Autonoma de Mexico, Facultad de Ciencias, Apartado Postal 70-542, Mexico D.F. (Mexico); Lerma, Sergio [Universidad Veracruzana, Facultad de Fisica e Inteligencia Artificial, Xalapa (Mexico)

    2013-01-15

    Microscopic studies in heavy nuclei are very scarce due to large valence spaces involved. This computational problem can be avoided by means of the use of symmetry-based models. Ground-state, {gamma} and {beta} bands, and their B(E2) transition strengths in {sup 160-168}Dy isotopes, are studied in the framework of the pseudo-SU(3) model which includes the preserving symmetry Q . Q term and the symmetry-breaking Nilsson and pairing terms, systematically parametrized. Additionally, three rotor-like terms are considered, whose free parameters, fixed for all members of the chain, are used to fine tune the moment of inertia of rotational bands and the band head of {gamma} and {beta} bands. The model succesfully describes in a systematic way rotational features in these nuclei and allows to extrapolate toward the midshell nucleus {sup 170}Dy. The results presented show that it is possible to study a full chain of isotopes or isotones in the region with the present model. (orig.)

  9. Electro-magnetic properties of heavy nuclei

    International Nuclear Information System (INIS)

    Otsuka, Takaharu

    1989-01-01

    Two topics of electro-magnetic properties of heavy nuclei are discussed. The first topic is the M1 excitation from well-deformed heavy nuclei, and the other is the sudden increase of the isotope shift as a function of N in going away from the closed shell. These problems are considered in terms of the particle-number projected (Nilsson-) BCS calculation. (author)

  10. Unstable systems and repeated measurements. II

    International Nuclear Information System (INIS)

    Exner, P.

    1977-01-01

    Two examples are treated. In the first, the chamber structure is only assumed to be periodic and P(t) is an exponential. In the second example no specific assumption is made about the primary decay law and the measuring device is structured as an idealized spark chamber. This example contains the results by Beskow and Nilsson as a special case. (author)

  11. Northeast Artificial Intelligence Consortium Annual Report. Volume 2. 1988 Discussing, Using, and Recognizing Plans (NLP)

    Science.gov (United States)

    1989-10-01

    Encontro Portugues de Inteligencia Artificial (EPIA), Oporto, Portugal, September 1985. [15] N. J. Nilsson. Principles Of Artificial Intelligence. Tioga...FI1 F COPY () RADC-TR-89-259, Vol II (of twelve) Interim Report October 1969 AD-A218 154 NORTHEAST ARTIFICIAL INTELLIGENCE CONSORTIUM ANNUAL...7a. NAME OF MONITORING ORGANIZATION Northeast Artificial Of p0ilcabe) Intelligence Consortium (NAIC) Rome_____ Air___ Development____Center

  12. Transition Probabilities in {sup 189}Os

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G; Berg, V; Baecklin, A

    1970-02-15

    The level structure of {sup 189}Os has been studied from the decay of {sup 189}Ir (13,3 days) produced in proton spallation at CERN and mass separated in the ISOLDE on-line facility. The gamma-ray spectrum has been recorded both with a high resolution Si(Li) - detector and Ge(Li) - detectors. Three previously not reported transitions were observed defining a new level at 348.5 keV. Special attention was given to the low energy level band structure. Several multipolarity mixing ratios were deduced from measured L-subshell ratios which, together with measured level half-lives, gave absolute transition probabilities. The low level decay properties are discussed in terms of the Nilsson model with the inclusion of Coriolis coupling.

  13. Stability of thermal HFB and dissipative thermal RPA

    CERN Document Server

    Tanabe, K

    1999-01-01

    It is shown that, as for a Nilsson + pairing model, the extended stability condition of the thermal Hartree-Fock-Bogoliubov (THFB) solution coincides with the one of the thermal RPA (TRPA) solution unless the pairing constant G is too large. As possible extensions of the TRPA equation in alternative ways describing thermal fluctuation effect, the extended TRPA (ETRPA) and the dissipative TRPA (DTRPA) are discussed. Furthermore, the general microscopic framework of the TRPA predicts the saturation and decrease of giant resonance width in high temperature limit, i.e. the fragmentation width GAMMA sub f propor to(kT) sup ( sup - sup 3 sup ( sup 2 sup ) sup ) and the spreading width GAMMA suparrow down propor to(kT) sup ( sup - sup 1 sup ( sup 2 sup ) sup ).

  14. Absolute El, {delta}K= O Transition Rates in Odd-Mass Pm and Eu-Isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G

    1967-06-15

    The half life of the 5/2{sup -} (532) intrinsic state in {sup 151}Pm, {sup 153}Eu and {sup 155}Eu has been determined by the delayed coincidence method. The absolute E1, {delta}K = 0 transition probabilities between the 5/2{sup -} (532) -> 5/2{sup +} (413) intrinsic states have been deduced and compared with theoretical predictions, using the Nilsson model as a starting point. The effect on the predicted transition probabilities obtained by adding pairing correlations and Coriolis coupling have also been studied. It has been found that the experimental transition rates, which are still strongly enhanced, cannot be explained by these contributions alone. It is therefore suggested that collective dipole contributions like those arising through the octupole excitations are of importance.

  15. Collective and non-collective structures in nuclei of mass region A ≈ 125

    International Nuclear Information System (INIS)

    Singh, A. K.

    2014-01-01

    Generation of angular momentum in nuclei is a key question in nuclear structure studies. In single particle model, it is due to alignment of spin of individual nucleon available in the valence space, whereas coherent motion of nucleons are assumed in the collective model. The nuclei near the closed shell at Z = 50 with mass number A ≈ 120-125 represent ideal cases to explore the interplay between these competing mechanisms and the transition from non-collective to collective behavior or vice versa. Recent spectroscopic studies of nuclei in this region reveal several non-collective maximally aligned states representing the first kind of excitation mechanism, where 8-12 particles above the 114 Sn align their spins to generate these states. Deformed rotational bands feeding the non-collective states in the spin range I=20-25 and excitation energies around 10 MeV have also been observed. Structure of the collective and non-collective states are discussed in the framework of Cranked-Nilsson-Strutinsky model

  16. Unified description of structure and reactions: implementing the nuclear field theory program

    International Nuclear Information System (INIS)

    Broglia, R A; Bortignon, P F; Barranco, F; Vigezzi, E; Idini, A; Potel, G

    2016-01-01

    The modern theory of the atomic nucleus results from the merging of the liquid drop model of Niels Bohr and Fritz Kalckar, and of the shell model of Marie Goeppert Meyer and Hans Jensen. The first model contributed the concepts of collective excitations. The second, those of independent-particle motion. The unification of these apparently contradictory views in terms of the particle-vibration and particle-rotation couplings carried out by Aage Bohr and Ben Mottelson has allowed for an ever more complete, accurate and detailed description of nuclear structure. Nuclear field theory (NFT), developed by the Copenhagen–Buenos Aires collaboration, provided a powerful quantal embodiment of this unification. Reactions are not only at the basis of quantum mechanics (statistical interpretation, Max Born), but also the specific tools to probe the atomic nucleus. It is then natural that NFT is being extended to deal with processes which involve the continuum in an intrinsic fashion, so as to be able to treat them on an equal footing with those associated with bound states (structure). As a result, spectroscopic studies of transfer to continuum states could eventually make use of the NFT rules, properly extended to take care of recoil effects. In the present contribution we review the implementation of the NFT program of structure and reactions, setting special emphasis on open problems and outstanding predictions. (invited comment)

  17. Operations Monitoring Assistant System Design

    Science.gov (United States)

    1986-07-01

    Logic. Artificial Inteligence 25(1)::75-94. January.18. 41 -Nils J. Nilsson. Problem-Solving Methods In Artificli Intelligence. .klcG raw-Hill B3ook...operations monitoring assistant (OMA) system is designed that combines operations research, artificial intelligence, and human reasoning techniques and...KnowledgeCraft (from Carnegie Group), and 5.1 (from Teknowledze). These tools incorporate the best methods of applied artificial intelligence, and

  18. Armastuse Armee süütab täna Snelli tiigi ääres südame / Askur Alas

    Index Scriptorium Estoniae

    Alas, Askur, 1973-

    2005-01-01

    Valgusfestivali üritustest Tallinnas. 14. jaanuaril Shnelli tiigi ääres toimuval tuleskulptuuride võistlusel osaleva Rootsi võistkonna Armastuse Armee tuleetendusest räägivad võistkonna juht skulptor Gunnar Carl Nilsson ja maalikunstnik Ola Öhlin. Veebruari algul vanalinna kohale kerkiva valguskupli idee autorid on hollandlased Winy Maas ja Rogier van der Heide. 25. jaanuaril seatakse üles büroo Kavakava installatsioon "Tallinna talje"

  19. Investigation of antimagnetic rotation in {sup 100}Pd

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, S.; Garg, U.; Afanasjev, A. V.; Frauendorf, S.; Kharraja, B.; Ghugre, S. S.; Chintalapudi, S. N.; Janssens, R. V. F.; Carpenter, M. P.; Kondev, F. G. (and others)

    2001-10-01

    High spin states have been studied in the nucleus {sup 100}Pd with the aim of investigating the novel phenomenon of ''antimagnetic rotation.'' A cascade of four ''rotational-band-like'' transitions is proposed as corresponding to antimagnetic rotation, based on the observed spectroscopic properties and a comparison with calculations in the configuration-dependent cranked Nilsson-Strutinsky formalism.

  20. Laser System Usage in the Marine Environment: Applications and Environmental Considerations

    Science.gov (United States)

    2010-12-01

    publications/pubs/index.html. Released by Bart Chadwick, Head Environmental Sciences Branch Under authority of Martin Machniak, Head Research...Nilsson and Lindstrom , 1983; Shelton, Gaten, and Chapman, 1985). Data on the effects of laser energy to corals also are lacking, although it can be...L. and M. Lindstrom . 1983. “Retinal Damage and Sensitivity Loss of a Light- Sensitive Crustacean Compound Eye (Cirolana borealis): Electron

  1. Tuhkatriinust printsessiks / Heie Treier

    Index Scriptorium Estoniae

    Treier, Heie, 1963-

    1999-01-01

    Ida- ja Kesk-Euroopa 1990ndate kunsti näitus 'Pärast müüri' ('After the Wall') Stockholmis Moderna Museetis. Kureerinud David Elliott, Bojana Pejic, Iris Müller-Westermann. Seminarist. Eesti kunstnike Jaan Toomiku, Kai Kaljo, Liina Siibi, Inessa Josingu esinemisest. Kommenteerivad Moskva kuraator J. Bakstein, rootsi kunstikriitik C. Chambert, makedoonia kuraator S. Milevska, ajakirja NU toimetaja J.-P. Nilsson, New Yorgi kunstikriitik K. Levin

  2. On the feeding and spectroscopy of superdeformed states

    International Nuclear Information System (INIS)

    Aberg, S.

    1987-03-01

    Based on a cranked Nilsson calculation we discuss some spectroscopic properties of superdeformed nuclei, like quadrupole moments, g-factors, energies and moments of inertia. In light of recent experimental information about superdeformations in 152 Dy, possible feeding mechanisms of these states are discussed. The high-spin level density is calculated in a microscopic model, and the number of superdeformed states, compared to normal-deformed states, is found to be high for high spins and for low excitation energies. This suggests favoured regions in the (E exc ,I)-plane for the feeding of superdeformed states. A microscopic model for rotational damping is presented, and the E2-strength function up to about 4 MeV excitation energy is studied. The rotatinal cooling at 1 ≅ 50 in the superdeformed HD Dy is found to be much smaller than in the normal-deformed 168 Yb. (orig.)

  3. Study of once and twice forbidden {beta} transitions; Contribution a l'etude de transitions {beta} une fois et deux fois interdites

    Energy Technology Data Exchange (ETDEWEB)

    Hocquenghem, J C [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1967-09-01

    The realisation of an experimental set up for directional angular correlation measurements allowed us to determine {beta} - {gamma} angular correlations. These measurements together with the determination of the {beta} shape-factor have been made for the following transitions: the first forbidden {beta}{sup -} transitions of 386 keV in the {sup 177}Lu disintegration and of 352 keV in the {sup 175}Yb disintegration. The experimental results have been compared with theoretical predictions of the Nilsson's model; the twice forbidden {beta}{sup -} transition of 473 keV in the {sup 94}Nb disintegration. The {beta} transition nuclear matrix elements have been extracted from the experimental results. Comparison have been made with the theoretical values calculated by taking for nuclear wavefunctions those obtained by diagonalization of the residual interaction and assuming that protons and neutrons outside the {sup 90}Zr core are respectively on the 1 g 9/2 and 2 d 5/2 orbits. (author) [French] La realisation d'un ensemble de mesures de correlations angulaires directionnelles nous a permis la mesure de correlations {beta} - {gamma} en fonction de l'energie. En completant celles-ci par la mesure du facteur de forme du spectre {beta}, nous avons pu etudier ainsi: d'une part, les transitions {beta}{sup -} une fois interdites de 386 keV de la desintegration de {sup 177}Lu et de 352 keV de la desintegration de {sup 175}Yb, Les resultats experimentaux ont ete compares aux valeurs calculees dans le modele de Nilsson; d'autre part, la transition {beta}- deux fois interdite de 473 keV de la desintegration de {sup 94}Nb. Les elements de matrice nucleaire de la transition {beta}, extraits des resultats experimentaux, ont ete compares aux valeurs theoriques calculees. Les fonctions d'ondes nucleaires utilisees ont ete obtenues par diagonalisation de l'interaction residuelle en supposant que les protons et les neutrons, en dehors du coeur forme par le {sup 90}Zr, sont respectivement

  4. Systematics of Absolute Gamma Ray Transition Probabilities in Deformed Odd-A Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G

    1965-11-15

    All known experimentally determined absolute gamma ray transition probabilities between different intrinsic states of deformed odd-A nuclei in the rare earth, region (153 < A < 181) and in the actinide region (A {>=} 227) are compared with transition probabilities (Weisskopf and Nilsson estimate). Systematic deviations from the theoretical values are found. Possible explanations for these deviations are given. This discussion includes Coriolis coupling, {delta}K ={+-}2 band-mixing effects and pairing interaction.

  5. Using T2-Exchange from Ln3+DOTA-Based Chelates for Contrast-Enhanced Molecular Imaging of Prostate Cancer with MRI

    Science.gov (United States)

    2016-04-01

    thereby performing disease staging entirely non-invasively. Also, in contrast to PET/CT or SPECT/CT, disease diagnostics and therapy monitoring would...2011;6.e27370. 11. Zhang SR, Sherry AD. Physical characteristics of lanthanide com- plexes that act as magnetization transfer (MT) contrast agents. J...reper- fused and nonreperfused myocardial infarctions - MR imaging with dysprosium-DTPA-BMA in the pig. Acta Radiol 1996;37:18–26. 28. Nilsson S

  6. Preliminary Study of Aquatic Hyphomycetes from Venezuelan streams

    OpenAIRE

    SMITS, Gunta; FERNÁNDEZ, Rafael; CRESSA, Claudia

    2007-01-01

    Fifty species of aquatic hyphomycetes from seven streams, six of which are located in Venezuelan National Parks are reported. Community similarity of hyphomycetes was low since only four species were common to all sites: Campylospora chaetocladia Ranzoni, Clavatospora tentacula Sv.Nilsson, Triscelophorus acuminatus Nawawi and Triscelophorus monosporus Ingold. The streams had unique species whose number varies between one and three. In Río Los Castillos the species were: Anguillospora longissi...

  7. Svag analys ger allt för långtgående konsekvenser

    DEFF Research Database (Denmark)

    Thinggaard, Frank; Nilsson, Sven-Arne

    2007-01-01

    I IASB:s diskussionsrapport om möjliga värderingsgrunder vid första redovisningstillfället föreslås att tillgångar och skulder värderas till verkligt värde. I Balans 3/2007 redogjorde Frank Thinggaard och Sven-Arne Nilsson för kriterierna och tillvägagångssättet vid prövningen av relevans. I denn...

  8. It Takes Two to Tango: Entrepreneurship and Creativity in Troubled Times – Vietnam 2012

    OpenAIRE

    Dang Le Nguyen, Vu; Napier, Nancy K.; Vuong, Quan-Hoang

    2012-01-01

    Strikingly, most literature suggests that market competition will push firms to take creativity/innovation seriously as matter of death or survival. Using the data, we examined creativity methods (Napier and Nilsson, 2008; Napier, 2010) in conjunction with three influential cultural values – namely risk tolerance, relationship, and dependence on resources – to assess how they influence decisions of entrepreneurs.The primary objective of this study focuses on perceived values of entrepreneursh...

  9. Impact of triaxiality on the rotational structure of neutron-rich rhenium isotopes

    Directory of Open Access Journals (Sweden)

    M.W. Reed

    2016-01-01

    Full Text Available A number of 3-quasiparticle isomers have been found and characterised in the odd-mass, neutron-rich, 187Re, 189Re and 191Re nuclei, the latter being four neutrons beyond stability. The decay of the isomers populates states in the rotational bands built upon the 9/2−[514] Nilsson orbital. These bands exhibit a degree of signature splitting that increases with neutron number. This splitting taken together with measurements of the M1/E2 mixing ratios and with the changes observed in the energy of the gamma-vibrational band coupled to the 9/2−[514] state, suggests an increase in triaxiality, with γ values of 5°, 18° and 25° deduced in the framework of a particle-rotor model.

  10. Absence of paired crossing in the positive parity bands of 124Cs

    Science.gov (United States)

    Singh, A. K.; Basu, A.; Nag, Somnath; Hübel, H.; Domscheit, J.; Ragnarsson, I.; Al-Khatib, A.; Hagemann, G. B.; Herskind, B.; Elema, D. R.; Wilson, J. N.; Clark, R. M.; Cromaz, M.; Fallon, P.; Görgen, A.; Lee, I.-Y.; Ward, D.; Ma, W. C.

    2018-02-01

    High-spin states in 124Cs were populated in the 64Ni(64Ni,p 3 n ) reaction and the Gammasphere detector array was used to measure γ -ray coincidences. Both positive- and negative-parity bands, including bands with chiral configurations, have been extended to higher spin, where a shape change has been observed. The configurations of the bands before and after the alignment are discussed within the framework of the cranked Nilsson-Strutinsky model. The calculations suggest that the nucleus undergoes a shape transition from triaxial to prolate around spin I ≃22 of the positive-parity states. The alignment gain of 8 ℏ , observed in the positive-parity bands, is due to partial alignment of several valence nucleons. This indicates the absence of band crossing due to paired nucleons in the bands.

  11. First measurement of the decoupling parameter for the K = 1 band of {sup 156}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Beck, Tobias; Beller, Jacob; Gayer, Udo; Pietralla, Norbert; Ries, Philipp; Ries, Christopher; Werner, Volker; Zweidinger, Markus [IKP, TU Darmstadt (Germany); Derya, Vera [IKP, Universitaet zu Koeln (Germany); Isaak, Johann; Loeher, Bastian [EMMI, GSI, Darmstadt (Germany); FIAS, Frankfurt (Germany); Scheck, Marcus [IKP, TU Darmstadt (Germany); School of Engineering, UWS Paisley (United Kingdom); SUPA, Glasgow (United Kingdom); Tornow, Werner; Weller, Henry R. [Duke University, Durham (United States)

    2016-07-01

    In a deformed nucleus the nuclear states are combinations of an intrinsic motion and a rotational motion of the core. In this scenario the Coriolis force changes the projection of the angular momentum on the symmetry axis and admixes different K values. The effects of the Coriolis interactions have been observed experimentally for K = 1/2 bands. The recent observation of the first excited rotational state of the isovector low-lying J{sup π}{sub K} = 1{sup +}{sub 1} scissors mode in a (γ,γ{sup '}) experiment inaugurates a case to study the Coriolis decoupling for K = 1 bands. In the talk, the theoretical description provided by Bohr and Mottelson is presented, and their adaption to the particular case is explained alongside the ongoing analysis and open questions.

  12. Internal bremsstrahlung spectra from 185W and 32P

    International Nuclear Information System (INIS)

    Babu, R.P.; Murty, K.N.; Murty, V.A.N.

    1976-01-01

    The internal bremsstrahlung spectra from the β decay of 185 W and 32 P were measured using a NaI(Tl) scintillation spectrometer with a standard geometrical arrangement. After making all the necessary corrections the experimental results are compared with the allowed theory of the Knipp, Uhlenbeck, and Bloch (KUB theory) and also with the Coulomb corrected theories of Lewis, Ford, and Nilsson. In the case of 185 W it is found that from 78 to 200 keV the experimental distribution is in good agreement with the KUB theory whereas beyond 200 keV and below 78 keV the experimental points are far above even the highest Coulomb corrected theoretical distribution of Nilsson. The internal bremsstrahlung from this isotope has not been previously investigated. In the case of 32 P the experimental relative intensity spectrum is compared with the KUB theory and also with the Coulomb corrected theory of Lewis and Ford. Fairly good agreement is obtained from 30 to 200 keV with the KUB theory but in the energy region from 200 to 900 keV, the experimental results deviate positively from both the KUB and Lewis and Ford theories. The experimental excess over the Lewis and Ford theory is 15% on the average

  13. On the octupole deformation in Ra-Th region

    International Nuclear Information System (INIS)

    Rozmej, P.; Boening, K.; Sobiczewski, A.

    1986-03-01

    The problem of the existence of a stable octupole deformation in Ra-Th region has been reinvestigated using a Nilsson single-particle potential with a newly fitted set of parameters, which reproduce the spins of the ground states of odd-A nuclei. In the energy surfaces, calculated for 222 Ra and 222 Th, the octupole deformed minima, separated by the barriers of 150 KeV and 210 keV, respectively, have been obtained. (orig.)

  14. Levels in /sup 179/W studied in the /sup 181/Ta(p, 3n) reaction by on-line electron and gamma ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Meijer, B J; Konijn, J [Instituut voor Kernphysisch Onderzoek, Amsterdam (Netherlands); Klank, B; Jett, J H; Ristinen, R A [Colorado Univ., Boulder (USA)

    1975-01-01

    Levels in /sup 179/W have been deduced from in-beam gamma and conversion electron studies of the /sup 181/Ta(p, 3n)/sup 179/W reaction. The gamma-ray spectrum was studied with Ge(Li) detectors and a crystal diffraction spectrometer; the conversion electrons were measured with solenoid Si(Li) spectrometer. The multipolarities of some 50 transitions could be determined. Coriolis mixing of the Nilsson orbits with N = 6 was calculated.

  15. Northeast Artificial Intelligence Consortium (NAIC) Review of Technical Tasks. Volume 2, Part 2.

    Science.gov (United States)

    1987-07-01

    1979. 20. Nau, Dana S., "Expert Computer Systems", I7E7 Computer pp. 63-85, January 1983. 477...Edinburgh, -v .. 1979. 20. Nau, Dana S., "Expert Computer Systems,- IEEE Computer, pp. 63-85, January 1983. 21. Nilsson, Nils J., ___ -. Artificial...Percept... Saltzman , E.L. and Kelso, J.A.S., (1983), "Skilled Actions: A Task Dynamic Approach", Haskins Labs, SR-76, pp. 3-50. Seneff, Stephanie, (1985

  16. SEISMIC SIMULATIONS USING PARALLEL COMPUTING AND THREE-DIMENSIONAL EARTH MODELS TO IMPROVE NUCLEAR EXPLOSION PHENOMENOLOGY AND MONITORING

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, A; Matzel, E; Pasyanos, M; Petersson, A; Sjogreen, B; Bono, C; Vorobiev, O; Antoun, T; Walter, W; Myers, S; Lomov, I

    2008-07-07

    The development of accurate numerical methods to simulate wave propagation in three-dimensional (3D) earth models and advances in computational power offer exciting possibilities for modeling the motions excited by underground nuclear explosions. This presentation will describe recent work to use new numerical techniques and parallel computing to model earthquakes and underground explosions to improve understanding of the wave excitation at the source and path-propagation effects. Firstly, we are using the spectral element method (SEM, SPECFEM3D code of Komatitsch and Tromp, 2002) to model earthquakes and explosions at regional distances using available 3D models. SPECFEM3D simulates anelastic wave propagation in fully 3D earth models in spherical geometry with the ability to account for free surface topography, anisotropy, ellipticity, rotation and gravity. Results show in many cases that 3D models are able to reproduce features of the observed seismograms that arise from path-propagation effects (e.g. enhanced surface wave dispersion, refraction, amplitude variations from focusing and defocusing, tangential component energy from isotropic sources). We are currently investigating the ability of different 3D models to predict path-specific seismograms as a function of frequency. A number of models developed using a variety of methodologies are available for testing. These include the WENA/Unified model of Eurasia (e.g. Pasyanos et al 2004), the global CUB 2.0 model (Shapiro and Ritzwoller, 2002), the partitioned waveform model for the Mediterranean (van der Lee et al., 2007) and stochastic models of the Yellow Sea Korean Peninsula region (Pasyanos et al., 2006). Secondly, we are extending our Cartesian anelastic finite difference code (WPP of Nilsson et al., 2007) to model the effects of free-surface topography. WPP models anelastic wave propagation in fully 3D earth models using mesh refinement to increase computational speed and improve memory efficiency. Thirdly

  17. Level structure of 149Nd. The decay of 149Pr

    International Nuclear Information System (INIS)

    Pinston, J.A.; Roussille, R.; Sadler, G.; Tenten, W.; Bocquet, J.P.; Pfeiffer, B.; Warner, D.D.

    1977-01-01

    The decay of 149 Pr (Tsub(1/2) = 2.2 min) has been studied using the two fission product separators JOSEF and LOHENGRIN to produce the 149 Pr nucleus. A level scheme for 149 Nd has been established. The β-branching of log ft values for the excited levels were deduced from the analysis of γ-intensity balances. Furthermore, the spins and parities for most of the excited states observed were obtained from the comparison between the present work, the neutron capture results and the pick-up reactions. The positive parity levels have been described with the Nilsson model with Coriolis and ΔN = 2 interactions included. The properties of the negative parity states cannot be explained as easily; however, it has been attempted to extract the structure of the ground state and the first excited states. (orig.) [de

  18. Systematic study of β-band and correlation with g- band using power law and soft rotor formula

    International Nuclear Information System (INIS)

    Katoch, Vikas; Kaushik, Reetu; Sharma, S.; Gupta, J.B.

    2014-01-01

    The nuclear structure of even Z even N medium mass transitional nuclei consist of ground state band, K π =0 1 β-band, K π =2 1 γ- band and other higher bands. As we move away from closed shell, energy levels are low lying from spherical to deformed nuclei and energy deviated from ideal rotor behavior. The energy of these transitional nuclei in ground band can also be studied using Bohr Mottelson energy expression, Soft Rotor Formula (SRF), Power Law (PL) etc. Recently, Gupta et al. (2013) modified SRF for non zero band head K π =2 1 γ-band and reproduced the level energies. Here same formula applied for K π =0 1 β-band and the level energies are reproduced and compared with experimental energies. The power law is also used for recalculation of level energies and for useful comparison

  19. In vitro pharmacological characterization of a novel TRPA1 antagonist and proof of mechanism in a human dental pulp model

    Directory of Open Access Journals (Sweden)

    Nyman E

    2013-01-01

    Full Text Available Eva Nyman,1,* Bo Franzén,1,* Andreas Nolting,1 Göran Klement,1 Gang Liu,1 Maria Nilsson,1 Annika Rosén,2 Charlotta Björk,3 Dirk Weigelt,4 Patrik Wollberg,1 Paul Karila,1 Patrick Raboisson11Neuroscience, Innovative Medicines CNS/Pain, AstraZeneca R&D, Södertälje, Sweden; 2Division of Oral and Maxillofacial Surgery, Karolinska Institute/Karolinska University Hospital, Huddinge, Sweden; 3Clinical TA NS Early Development, 4Medicinal Chemistry, Innovative Medicines CNS/Pain, AstraZeneca R&D, Södertälje, Sweden*These authors contributed equally to this workAbstract: AZ465 is a novel selective transient receptor potential cation channel, member A1 (TRPA1 antagonist identified during a focused drug discovery effort. In vitro, AZ465 fully inhibits activation by zinc, O-chlorobenzylidene malononitrile (CS, or cinnamaldehyde of the human TRPA1 channel heterologously expressed in human embryonic kidney cells. Our data using patch-clamp recordings and mouse/human TRPA1 chimeras suggest that AZ465 binds reversibly in the pore region of the human TRPA1 channel. Finally, in an ex vivo model measuring TRPA1 agonist-stimulated release of neuropeptides from human dental pulp biopsies, AZD465 was able to block 50%–60% of CS-induced calcitonin gene-related peptide release, confirming that AZ465 inhibits the native human TRPA1 channel in neuronal tissue.Keywords: pain, pharmacology, antagonist, chimeric proteins, dental pulp, inflammation, neuropeptide, calcitonin gene-related peptide, CGRP

  20. Spectroscopy of odd-proton nuclei in the region of 254No

    International Nuclear Information System (INIS)

    Ketelhut, S.; Greenlees, P. T.; Eeckhaudt, S.; Jones, P.; Julin, R.; Juutinen, S.; Kettunen, H.; Leino, M.; Leppaenen, A.-P.; Nieminen, P.; Nyman, M.; Perkowski, J.; Rahkila, P.; Saren, J.; Scholey, C.; Uusitalo, J.; Chatillon, A.; Bouchez, E.; Clement, E.; Goergen, A.

    2008-01-01

    Two rotational bands have been found in the transfermium nuclei 251 Md and 255 Lr, the latter being the heaviest nucleus so far studied in-beam. Both are assigned to a [521]1/2 - Nilsson state by comparison to theory. The experiments have been carried out in the Accelerator Laboratory of the University of Jyvaeskylae (JYFL), where the array of germanium detectors JUROGAM was used in conjunction with the recoil-seperator RITU and the focal-plane setup GREAT for gamma-spectroscopic studies

  1. Advanced Space Propulsion Study - Antiproton and Beamed Power Propulsion

    Science.gov (United States)

    1987-10-01

    H. Koch, A. Kreissl, H. Poth, U. Raich, D. Rohmann, C. Backenstoss, Ch. Findeisen , J. Repond, L. Tauscher, A. Nilsson, S. Carius, M. Suffert, S...Backenstcss, I. Bergstr8m, S. Carius, S. Chj&rLlambous, M.D. Cooper, Ch. Findeisen , D. Hatsifotiadou, M. Hugi, A. Kerek, H.O. Meyer, P. Pavlopoulos, J. Repond...Chjaralambous, M.D. Cooper, Ch. Findeisen . D. Hatzifotiadou, M. Hugi, A. Kerek, H.O. Meyer, P. Pavlopoulos, J. Repond, L. T&uscher, D. Tr8ster, M.C.S

  2. High spin states and the competition of spherical and strongly deformed shapes in the A = 70 to 80 region

    International Nuclear Information System (INIS)

    Hamilton, J.H.; Ramayya, A.V.; Piercey, R.B.

    1982-01-01

    A wide variety of collective band structures are seen in Ge to Sr nuclei to make this an important new testing ground for nuclear models. These include bands built on coexisting and competing near-spherical and deformed shapes, γ vibrational bands and multiple positive and negative parity bands. Ground state bands in Ge and Kr but not 78 80 Sr are crossed at the 8 + to 12 + levels. Gaps in the Nilsson levels for both N and Z = 38 at large deformation lead to large ground state deformation in Kr and Sr around N = 38. The crossing of rotation aligned bands based on (g/sub 9/2/) 2 configuration are correlated with the ground state deformations. A second high spin crossing is seen in 74 Kr. Measured g factors in 68 Ge yield a two-quasineutron structure for the 8 2 + state. 30 references

  3. Experimental and theoretical study of several nuclei from the 1f(7/2) region for mass number 47, 48, 49

    International Nuclear Information System (INIS)

    Haas, Bernard.

    1974-01-01

    The experimental study of the following nuclei 48 V, 49 V and 48 Cr has been undertaken by in-beam γ-ray spectroscopy. The nuclear structure has been deduced from angular distribution and particle-γ angular correlation measurements as well as lifetime measurements with the Doppler shift technique. Most of the energy levels could be classified in rotational bands followings quite well the low I(I+1):K(π)=1 - ( 48 V), K(π)=3/2 + and 1/2 + ( 49 V) and K(π)=0 + ( 48 Cr). The properties of these bands, as for example the B(E2) reduced matrix elements and the intrinsic quadrupole moments Q 0 have been described in the framework of the Nilsson model using a deformation parameter β approximately 0.3. The negative parity levels of the cross-conjugate nuclei 47 V- 49 Cr and 49 V- 47 Ti have also been explained by a collective model, however a strong configuration mixing in their wave function, due to the Coriolis interaction, destroys the energy dependence in I(I+1) [fr

  4. Heuristics can produce surprisingly rational probability estimates: Comment on Costello and Watts (2014).

    Science.gov (United States)

    Nilsson, Håkan; Juslin, Peter; Winman, Anders

    2016-01-01

    Costello and Watts (2014) present a model assuming that people's knowledge of probabilities adheres to probability theory, but that their probability judgments are perturbed by a random noise in the retrieval from memory. Predictions for the relationships between probability judgments for constituent events and their disjunctions and conjunctions, as well as for sums of such judgments were derived from probability theory. Costello and Watts (2014) report behavioral data showing that subjective probability judgments accord with these predictions. Based on the finding that subjective probability judgments follow probability theory, Costello and Watts (2014) conclude that the results imply that people's probability judgments embody the rules of probability theory and thereby refute theories of heuristic processing. Here, we demonstrate the invalidity of this conclusion by showing that all of the tested predictions follow straightforwardly from an account assuming heuristic probability integration (Nilsson, Winman, Juslin, & Hansson, 2009). We end with a discussion of a number of previous findings that harmonize very poorly with the predictions by the model suggested by Costello and Watts (2014). (c) 2015 APA, all rights reserved).

  5. Electric quadrupole giant resonance in the photofission of sup(238)U IFUSP-P--140

    International Nuclear Information System (INIS)

    Bhandari, B.S.; Arruda Neto, J.D.T.; Herdade, S.B.; Nascimento, I.C.

    1978-02-01

    The 238 U nucleus was studied measuring the electrofission yield and angular distributions of fission fragments, in the energy range of 5.5 to 28.3 MeV, using a new method of analysis. An E2 isoscalar giant resonance was found in the photofission cross section of 238 U. This resonance exhausts (71 + -7)% of the EWSR and is located at 9.9 + -0.2 MeV with a width of 6.8 + -0.4 MeV. The position of this resonance is in reasonable agreement with the Bohr and Mottelson prediction (58.Asup( - 1/3MeV). The width of 6.8 + -0.4 MeV is compatible with a possible triple splitting of the resonance. From the angular distributions of photofission fragments and yield measurements of multipoles other than E1, evidence of an M1 mixture in the energy region 6-7 MeV was found

  6. The Beatles i Sverige år 1963 : En studie om The Beatles studioinspelning på Karlaplan samt gruppens mottagande i media under samma turné

    OpenAIRE

    Nilsson, Ellinor

    2012-01-01

    Abstract Ellinor Nilsson: The Beatles i Sverige år 1963. En studie om The Beatles radioinspelning på Karlaplan och gruppens mottagande i media under samma turné [The Beatles in Sweden 1963. A study of The Beatles’ radio recording on Karlaplan and how the group was depicted in Swedish media during the tour]. Uppsala universitet: Institutionen för musikvetenskap, examensarbete 15 högskolepoäng, 2012. In October 1963 The Beatles started their first tour abroad, which took place in Sweden. Except...

  7. Verkligt värde vid första redovisningstillfället?

    DEFF Research Database (Denmark)

    Thinggaard, Frank; Nilsson, Sven-Arne

    2007-01-01

    I en första artikel av två diskuterar Frank Thinggaard och Sven-Arne Nilsson en rapport från IASB som föreslår verkligt värde istället för anskaffningsvärde vid första redovisningstillfället. Där rapporten står för nytänkande undersöker de om denär i linje med en rapport om förbättrad föreställni...

  8. “Vad är svenskhet för er?” *Lång tystnad* : En receptionsstudie om vilken roll filmen ”Sveriges bästa svensk” spelar i diskussioner som berör svenskhet och integration.

    OpenAIRE

    D Markovic, Emma; Nilsson, Martin

    2016-01-01

    Title: “What is Swedishness for you?” *Long silence* – A reception study about what role film as a medium with the film “Sveriges bästa svensk” can play in discussions that consist of Swedishness and integration. Authors: Emma D Markovic and Martin Nilsson. Research problem: In terms of reception of film in order to generate discussions on a determined theme, we identified a gap in the research field of integration and Swedishness. Therefore this study fills a great space in this field. Aim &...

  9. RDM lifetimes measurements in 179Re

    International Nuclear Information System (INIS)

    Chamoli, S.; Joshi, P.; Kumar, A.; Govil, I.M.; Singh, R.P.; Chatturvedi, L.

    2001-01-01

    The study of Re nuclei in the mass region from 170-190 is of particular interest as they lie in a region where the Nilsson orbitals exhibit large driving effects on the nuclear shape, presenting the strong possibility of shape coexistence. To see the variation of the deformation driving property of different bands and the other related phenomena like delay in band crossing frequency for intruder configuration h 92 in these nuclei with increasing in neutron number the lifetime measurement in 179 Re nucleus is done

  10. High-spin states in 136La and possible structure change in the N =79 region

    Science.gov (United States)

    Nishibata, H.; Leguillon, R.; Odahara, A.; Shimoda, T.; Petrache, C. M.; Ito, Y.; Takatsu, J.; Tajiri, K.; Hamatani, N.; Yokoyama, R.; Ideguchi, E.; Watanabe, H.; Wakabayashi, Y.; Yoshinaga, K.; Suzuki, T.; Nishimura, S.; Beaumel, D.; Lehaut, G.; Guinet, D.; Desesquelles, P.; Curien, D.; Higashiyama, K.; Yoshinaga, N.

    2015-05-01

    High-spin states in the odd-odd nucleus 136La, which is located close to the β -stability line, have been investigated in the radioactive-beam-induced fusion-evaporation reaction 124Sn(17N,5 n ). The use of the radioactive beam enabled a highly sensitive and successful search for a new isomer [14+,T1 /2=187 (27 ) ns] in 136La. In the A =130 -140 mass region, no such long-lived isomer has been observed at high spin in odd-odd nuclei. The 136La level scheme was revised, incorporating the 14+ isomer and six new levels. The results were compared with pair-truncated shell model (PTSM) calculations which successfully explain the level structure of the π h11 /2⊗ν h11/2 -1 bands in 132La and 134La. The isomerism of the 14+ state was investigated also by a collective model, the cranked Nilsson-Strutinsky (CNS) model, which explains various high-spin structures in the medium-heavy mass region. It is suggested that a new type of collective structure is induced in the PTSM model by the increase of the number of π g7 /2 pairs, and/or in the CNS model by the configuration change associated with the shape change in 136La.

  11. A united phenomenological description of quadrupole excitations in even-even nuclei

    International Nuclear Information System (INIS)

    Lipas, P.O.; Haapakoski, P.; Honkaranta, T.

    1975-05-01

    A phenomenological model is developed for the collective quadrupole properties of all even-even nuclei. Rotational, vibrational, and transitional nuclei are included in the model on an equal footing. A Bohr-type intrinsic Hamiltonian for harmonic quadrupole vibrations about an axially deformed shape is solved exactly. States of good angular momentum are projected out of the intrinsic states, and they are made orthogonal by a Schmidt scheme. The angular-momentum and phonon-number composition of the states is analyzed at various stages; states with K=1 are found spurious. Excitation energies for the ground, β and γ bands are calculated as expectation values of a radically simplified nuclear Hamiltonian in our projected and orthogonalized states. With increasing deformation the calculated energies evolve smoothly from the evenly spaced phonon spectrum to the Bohr-Mottelson rotational-vibrational spectrum according to the scheme of Sheline and Sakai. The basic model contains only two parameters (deformation d and energy scale) to fix the entire quadrupole spectrum of a nucleus. The results are given in the form of graphs suitable for immediate application; numerical results are readily produced by our computer code. The ground bands are fitted comparably to the VMI model, while the β and γ bands are reproduced qualitatively. The nuclei 152 Sm, 152 Gd, and 114 Cd are used as test cases. Quadrupole moments and E2 transition rates are also calculated. Intra-ground-band transition ratios and branching ratios from the β and γ bands are given in terms of the single parameter d. The results are applied to 152 Sm, with fair success. Finally the model to include two more parameters (anisotropy) is extended. The improvement over the basic model is modest in view of added parameters and computational effort. (author)

  12. Isomer spectroscopy of neutron-rich 168 Tb 103

    Energy Technology Data Exchange (ETDEWEB)

    Gurgi, L. A.; Regan, P. H.; Söderström, P. -A.; Watanabe, H.; Walker, P. M.; Podolyák, Zs.; Nishimura, S.; Berry, T. A.; Doornenbal, P.; Lorusso, G.; Isobe, T.; Baba, H.; Xu, Z. Y.; Sakurai, H.; Sumikama, T.; Catford, W. N.; Bruce, A. M.; Browne, F.; Lane, G. J.; Kondev, F. G.; Odahara, A.; Wu, J.; Liu, H. L.; Xu, F. R.; Korkulu, Z.; Lee, P.; Liu, J. J.; Phong, V. H.; Yag, A.; Zhang, G. X.; Alharbi, T.; Carroll, R. J.; Chae, K. Y.; Dombradi, Zs.; Estrade, A.; Fukuda, N.; Griffin, C.; Ideguchi, E.; Inabe, N.; Kanaoka, H.; Kojouharov, I.; Kubo, T.; Kubono, S.; Kurz, N.; Kuti, I.; Lalkovski, S.; Lee, E. J.; Lee, C. S.; Lotay, G.; Moon, C. -B.; Nishizuka, I.; Nita, C. R.; Patel, Z.; Roberts, O. J.; Schaffner, H.; Shand, C. M.; Suzuki, H.; Takeda, H.; Terashima, S.; Vajta, Zs.; Yoshida, S.; Valiente-Dòbon, J. J.

    2017-11-01

    In-flight fission of a 345 MeV per nucleon 238U primary beam on a 2 mm thick 9Be target has been used to produce and study the decays of a range of neutron-rich nuclei centred around the doubly mid-shell nucleus 170Dy at the RIBF Facility, RIKEN, Japan. The produced secondary fragments of interest were identified event-by-event using the BigRIPS separator. The fragments were implanted into the WAS3ABI position sensitive silicon active stopper which allowed pixelated correlations between implants and their subsequent β-decay. Discrete γ-ray transitions emitted following decays from either metastable states or excited states populated following beta decay were identified using the 84 coaxial high-purity germanium (HPGe) detectors of the EURICA spectrometer, which was complemented by 18 additional cerium-doped lanthanum bromide (LaBr3) fast-timing scintillation detectors from the FATIMA collaboration. This paper presents the internal decay of a metastable isomeric excited state in the odd-odd nucleus 168Tb, which corresponds to a single proton-neutron hole configuration in the valence maximum nucleus 170Dy. These data represent the first information on excited states in this nucleus, which is the most neutron-rich odd-odd isotope of terbium (Z=65) studied to date. Nilsson configurations associated with an axially symmetric, prolate-deformed nucleus are proposed for the 168Tb ground state the observed isomeric state by comparison with Blocked BCS-Nilsson calculations.

  13. Meta Isæus-Berlin: De animerade installationerna /The Animated Installations

    OpenAIRE

    Weimarck, Torsten

    2006-01-01

    Meta Isæus-Berlin: The Animated Installations Torsten Weimarck At about the same time that I saw Meta Isæus-Berlin’s remarkable installation Ett vattenhem (A Water Home) at the Bo01 Housing Fair in Malmö I also happened to see Johannes Stjärne Nilsson and Ola Simonsson’s film Music for one appartment and six drummers which was shown as a supporting film in the cinema. It struck me that these works had interesting things to say about each other; that in spite of their manife...

  14. How to measure distinct components of visual attention fast and reliably

    DEFF Research Database (Denmark)

    Vangkilde, Signe Allerup; Kyllingsbæk, Søren; Habekost, Thomas

    2009-01-01

    Measuring different attentional processes in a fast and reliable way is important in both clinical and experimental settings. However, most tests of visual attention are either lengthy or lack sensitivity, specificity, and reliability. To address this we developed a ten minute test procedure...... for the Swedish Betula-project, a longitudinal study investigating changes in cognitive functions over the adult life span (Nilsson et al., 2004). The test consists of a computer-based letter recognition task with stimulus displays of varied durations followed by pattern masks or a blank screen. The temporal...

  15. Employer branding på Q-Med : En fallstudie i hur företagsspecifika värden förmedlas till potentiella och befintliga medarbetare

    OpenAIRE

    Nilsson, Stina; Ljungmark, Erik

    2011-01-01

    Sammanfattning "Employer branding på Q-Med – En fallstudie i hur företagsspecifika värden förmedlas till potentiella och befintliga medarbetare" Datum: 19 januari, 2011 Nivå: Kandidatuppsats i företagsekonomi, 15 ECTS Institution: Akademin för hållbar samhälls‐ och teknikutveckling, HST, Mälardalens Högskola Författare: Erik Ljungmark 29 januari 1980, Stina Nilsson 25 april 1983 Titel: Employer branding på Q-Med – En fallstudie i hur företagsspecifika värden förmedlas till potentiella och...

  16. Collective structures in 185Hg

    International Nuclear Information System (INIS)

    Bourgeois, C.; Hildingsson, L.; Perrin, N.; Sergolle, H.; Hannachi, F.; Bastin, G.; Porquet, M.G.; Thibaud, J.P.; Beck, F.A.; Merdinger, J.C.

    1988-01-01

    Excited states of 185 Hg have been investigated via the 161 Dy ( 28 Si, 4n) reaction at 145 MeV. In-beam gamma-ray spectroscopy studies have been performed with the ''Chateau de Cristal'' 4π-multidetector array. Level scheme of 185 Hg has been established. Shape coexistence, still present in 185 Hg like in the neighbouring Hg isotopes, manifests itself through a weakly populated decoupled band built on the 13/2+ isomer and three strongly-coupled bands built on the prolate 1/2-[521], 7/2-[514], and 9/2+[624] Nilsson states

  17. Coulomb excitation of 189Os

    International Nuclear Information System (INIS)

    Brandao, S.B.

    1987-01-01

    The level structure of 189 Os has been studied by Coulomb excitation using 35 Cl, 28 Si, 16 O beams. GOSIA, a code written to analyze multiple Coulomb excitation, was used to obtain the reduced probabilities of transition B(E2). The results for interband and intraband turned out possible the classification of the states following Nilsson levels. Gamma-rays originating from deexcitation of 216.7 and 219.4 keV have been separated and the reduced probability of transition has been measured. (A.C.A.S.) [pt

  18. The β+ decay of 234Np and other isospin-forbidden 0+ -> 0+ Fermi transitions

    International Nuclear Information System (INIS)

    Yap, C.T.; Saw, E.L.

    1984-01-01

    Although experimental values of the Fermi nuclear matrix elements vary widely from about 1x10 -3 to 40x10 -3 for isospin-forbidden 0 + ->0 + β transitions, theoretical calculations using the Coulomb potential and Nilsson wave functions yielded values of Msub(F) in reasonably good agreement, except that of 234 Np. However, our calculation of Msub(F) for this decay as a function of the deformation parameter β yielded a value of Msub(F) in good agreement with experiment for values of β between 0.1 and 0.2. (orig.)

  19. Energy use in farm buildings

    OpenAIRE

    Hörndahl, Torsten

    2008-01-01

    In Sweden, the agricultural sector uses an estimated 3.7 TWh per year as electricity or fuel. About 34% of this total is estimated to be used in the production of beef, pork, eggs and milk, including the spreading of manure. Some energy is also used for harvesting ley and cereals as feed, which is not included. Most of the energy used is in the form of electricity (approx 63%). All these estimates are based on a 1981-1984 survey by Nilsson & Påhlstorp (1985). Most of the technical equipment i...

  20. Decay properties of Bk97243 and Bk97244

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I.; Kondev, F. G.; Greene, J. P.; Zhu, S.

    2018-01-01

    Electron capture decays of Bk-243 and Bk-244 have been studied by measuring the gamma-ray spectra of mass-separated sources and level structures of Cm-243 and Cm-244 have been deduced. In Cm-243, the electron capture population to the ground state, 1/2(+)[631], and 1/2(+)[620] Nilsson states have been observed. The octupole K-pi = 2(-) band was identified in Cm-244 at 933.6 keV. In addition, spins and parities were deduced for several other states and two-quasiparticle configurations have been tentatively assigned to them

  1. Non-predation natural mortality of Norway pout ( Trisopterus esmarkii ) in the North Sea

    DEFF Research Database (Denmark)

    Sparholt, H.; Larsen, L.I.; Nielsen, J. Rasmus

    2002-01-01

    Based on age disaggregated data on catch rates in bottom trawl surveys, commercial catches, and the number consumed by the North Sea piscivorous predators, new estimates of non-predation natural mortality, M1, are obtained for Norway pout [Trisopterus esmarkii (Nilsson)]. Simple log catch ratio a...... periods is not significant. Survey data from each quarter of the year show that the main mortality takes place between the 1st and the 2nd quarter of the year, i.e. from before to after spawning, thus pointing at spawning as the main factor....

  2. High spin states in 181Ir and backbending phenomena in the Os-Pt region

    Science.gov (United States)

    Kaczarowski, R.; Garg, U.; Funk, E. G.; Mihelich, J. W.

    1992-01-01

    The 169Tm(16O,4n)181Ir reaction has been employed to investigate the high spin states of 181Ir using in-beam γ spectroscopy. A well-developed system of levels built on the h9/2 subshell was identified up to a maximum spin of (41/2-). Two rotational bands built on the isomeric states with τ1/2=0.33 μs (Ex=289.2 keV) and 0.13 μs (Ex=366.2 keV), respectively, were observed. The deduced gK values of 1.19+/-0.11 and 1.50+/-0.12 indicate Nilsson assignments of 9/2-[514] and 5/2+[402], respectively, for the bandheads of these bands. A high spin (I>=19/2) isomer with τ1/2=22 ns was found at an excitation energy above 1.96 MeV. The experimental results are discussed in terms of rotational models including Coriolis coupling and providing for a stable triaxial shape of the 181Ir nucleus.

  3. Particle-number conserving analysis for the 2-quasiparticle and high-K multi-quasiparticle states in doubly-odd 174,176Lu

    International Nuclear Information System (INIS)

    Li Bingheng; Lei Yi'an; Zhang Zhenhua

    2013-01-01

    Two-quasiparticle bands and low-lying excited high-K four-, six-, and eight-quasiparticle bands in the doubly-odd 174,176 Lu are analyzed by using the cranked shell model (CSM) with the pairing correlations treated by a particle-number conserving (PNC) method, in which the blocking effects are taken into account exactly. The proton and neutron Nilsson level schemes for 174,176 Lu are taken from the adjacent odd-A Lu and Hf isotopes, which are adopted to reproduce the experimental bandhead energies of the one-quasiproton and one-quasineutron bands of these odd-A Lu and Hf nuclei, respectively. Once the quasiparticle configurations are determined, the experimental bandhead energies and the moments of inertia of these two- and multi-quasiparticle bands are well reproduced by PNC-CSM calculations. The Coriolis mixing of the low-K (K=|Ω 1 -Ω 2 |) two-quasiparticle band of the Gallagher-Moszkowski doublet with one nucleon in the Ω=1/2 orbital is analyzed. (authors)

  4. Absolute M1 and E2 Transition Probabilities in 233U

    International Nuclear Information System (INIS)

    Malmskog, S.G.; Hoejeberg, M.

    1967-08-01

    Using the delayed coincidence technique, the following half lives have been determined for different excited states in 233 U: T 1/2 (311.9 keV level) = (1.20 ± 0.15) x 10 -10 sec, T 1/2 (340.5 keV level) = (5.2 ± 1.0) x 10 -11 sec, T 1/2 (398.6 keV level) = (5.5 ± 2.0) x 10 -11 sec and T 1/2 (415.8 keV level) -11 sec. From these half life determinations, together with earlier known electron intensities and conversion coefficients, 22 reduced B(Ml) and B(E2) transition probabilities (including 9 limits) have been deduced. The rotational transitions give information on the parameters δ and (g K - g R ) . The experimental M1 and E2 transition rates between members of different bands have been analysed in terms of the predictions of the Nilsson model, taking also pairing correlations and Coriolis coupling effects into account

  5. The 1956 CERN Symposium

    CERN Document Server

    Jarlskog, Cecilia

    2014-01-01

    CERN, currently the largest organization in the world for particle physics, was founded in 1954. Originally located in Meyrin, at the outskirts of the city of Geneva in Switzerland, it has with time extended into neighboring France. The Theoretical Study Division of CERN, however, was created already in 1952, i.e., before the official inauguration of CERN. It was situated in Copenhagen. Christian Møller [1] was appointed (part-time) as the Director and there were two full time senior staff members, Gunnar Källén and Ben R. Mottelson. While constructing buildings and accelerators were in progress, an international conference was organized by CERN in the city of Geneva. This “CERN Symposium on High Energy Accelerators and Pion Physics”, 11–23 June 1956, attracted about 250 participants from outside CERN, among them at least 18 Nobel Laureates or future Laureates. Unfortunately, the participants from CERN are not listed in the Proceedings [2]. The conference focused on measuring devices such as bubbl...

  6. Report of the Study Group on Complete Spectroscopy

    International Nuclear Information System (INIS)

    Garrett, J.D.

    1989-01-01

    This report summarizes the topics considered in four discussions of about two hours each attended by most of the workshop participants. The contents of the lectures of David Radford, Fumihiko Sakata, Ben Mottelson, and Jerry Garret pertaining to Complete Spectroscopy are contained elsewhere in this proceedings. Most detailed nuclear structure information is derived from measurements of the spectroscopic properties (e.g. excitation energies, angular momenta, parities, lifetimes, magnetic moments, population cross sections, methods of decay, etc.) of discrete nuclear eigenstates. The present instrumentation allows in the best cases such measurements to approach the angular momentum limit imposed by fission and to as many as fifteen different excited bands. In anticipation of the new generation of detection equipment, such as the EUROBall and the GAMMASPHERE, the Complete Spectroscopy Study Group attempted to define the limits to such studies imposed by physical considerations and to consider some of the new, interesting physics that can be addressed from more complete discrete spectroscopic studies. 28 refs

  7. A historical overview of nuclear structure studies in Strasbourg Laboratories: instrumentation, measurements and theory modelling—hand-in-hand

    Science.gov (United States)

    Beck, F. A.

    2018-05-01

    This article overviews a long period of an important evolution in the nuclear structure research in Strasbourg Laboratories, focussed on tracking of the weaker and weaker experimental signals carrying the more and more important physics messages. In particular we address the research of signatures of the collective behaviour of the nucleus as suggested in the early works of Bohr, Mottelson and Rainwater—at high and very high angular momenta—as well as the competition between the collective and non-collective excitation modes. These ambitious goals were possible to achieve only by constructing powerful spectrometers and developing related detectors, electronics and data acquisition systems. The theoretical modelling developed in parallel, provided essential guidance when choosing the right experiments and optimising their realisation. Theory calculations were equally helpful in interpreting the results of experiments leading to a more complete understanding of the underlying physics. Moreover, thanks to the development of heavy ion accelerators, the Strasbourg centre was the place where crossed the ways of many experimenters from European countries both from the Western and from the Central part of Europe, the place of the gradual development of more and more sophisticated European gamma-spectrometers in collaboration with more and more laboratories from the increasing number of countries allowing for the frontier-level studies of the nuclear behaviour at very high angular momenta.

  8. Description of nuclear properties

    International Nuclear Information System (INIS)

    Faessler, A.

    1991-01-01

    The lectures want to give a survey about new developments in the description of nuclei. In a first chapter we try to derive nuclear properties from the basis theory of quantum chromodynamics. This is not rigorously possible. There are still many cracks in the bridge between QCD and nuclear structure. The basic ingredient for nuclear structure calculations is the nucleon-nucleon interaction. We shall discuss the nucleon-nucleon interaction in a quark model. In a further chapter we discuss the way to come from a bare nucleon-nucleon interaction in free space to an effective nucleon-nucleon interaction in a limited model space for nuclear structure calculations. Such nuclear structure calculations can be done as shell model calculations. But they are due to the large number of configurations limited to light nuclei. We discuss possibilities (MONSTER and VAMPIR) to enlarge the model space for medium heavy and heavy nuclei. As the example of the low lying isovector 1 + states we discuss collective models (Bohr - Mottelson Model, interacting Boson Model) with proton and neutron degrees of freedom. The same states can also be described microscopically with the Quasi-Particle Random Phase Approximation (QRPA). We discuss the removal of spurious states in RPA. We also discuss the calculation of form factors and compare with inelastic electron scattering data. Finally we apply QRPA to the double-beta decay. Grand unified models predict, that the neutrino is identical with his antiparticle, that it has a finite mass and a weak right-handed interaction. If these properties are found the standard model of the strong and the electro-weak interaction can not be correct. Presently we can only derive from lower limits of the half lives of neutrinoless double-beta decays upper limits of the neutrino mass and of the right-handedness of the weak interaction and lower limits of the mass of the right handed heavy vector boson, if a specific grand unified model is given. (author)

  9. Levels of 250Cf populated in the decay of 250Bk

    International Nuclear Information System (INIS)

    Uecke, J.W.

    1975-06-01

    The nuclide 250 Bk undergoes β-decay with a half-life of 3.2 h to 13.1 y 250 Cf. A study is undertaken of the excited states in 250 Cf populated by 250 Bk decay which results from the α-decay of 276d 254 Es. The general features of published level schemes for these nuclei are consistent with predictions of the Nilsson and collective models; however, there remain many undiscovered transitions and ambiguous or uncertain level assignments. In an attempt to confirm predictions of current theoretical models which account for nuclear level assignments in this nucleus, these gamma transitions and their levels have been studied. Twenty-eight new γ-rays were determined. The decay of 250 Bk is investigated primarily by high resolution gamma-ray singles spectrometry and supported in part by two-parameter gamma-gamma coincidence spectrometry. The equipment, comprised of a Ge(HP) and a large volume Ge(Li) detector, a 4096-channel two-parameter analyzer, and a PDP-8/e computer system, permitted significant improvement in sensitivity and accuracy over previous investigations on this nucleus. (11 figures, 2 tables) (U.S.)

  10. Joint analysis of ESR lineshapes and 1H NMRD profiles of DOTA-Gd derivatives by means of the slow motion theory

    Science.gov (United States)

    Kruk, D.; Kowalewski, J.; Tipikin, D. S.; Freed, J. H.; Mościcki, M.; Mielczarek, A.; Port, M.

    2011-01-01

    The "Swedish slow motion theory" [Nilsson and Kowalewski, J. Magn. Reson. 146, 345 (2000)] applied so far to Nuclear Magnetic Relaxation Dispersion (NMRD) profiles for solutions of transition metal ion complexes has been extended to ESR spectral analysis, including in addition g-tensor anisotropy effects. The extended theory has been applied to interpret in a consistent way (within one set of parameters) NMRD profiles and ESR spectra at 95 and 237 GHz for two Gd(III) complexes denoted as P760 and P792 (hydrophilic derivatives of DOTA-Gd, with molecular masses of 5.6 and 6.5 kDa, respectively). The goal is to verify the applicability of the commonly used pseudorotational model of the transient zero field splitting (ZFS). According to this model the transient ZFS is described by a tensor of a constant amplitude, defined in its own principal axes system, which changes its orientation with respect to the laboratory frame according to the isotropic diffusion equation with a characteristic time constant (correlation time) reflecting the time scale of the distortional motion. This unified interpretation of the ESR and NMRD leads to reasonable agreement with the experimental data, indicating that the pseudorotational model indeed captures the essential features of the electron spin dynamics.

  11. Skyrme RPA description of γ-vibrational states in rare-earth nuclei

    Directory of Open Access Journals (Sweden)

    Nesterenko V.O.

    2016-01-01

    Full Text Available The lowest γ-vibrational states with Kπ = 2+γ in well-deformed Dy, Er and Yb isotopes are investigated within the self-consistent separable quasiparticle random-phase-approximation (QRPA approach based on the Skyrme functional. The energies Eγ and reduced transition probabilities B(E2γ of the states are calculated with the Skyrme force SV-mas10. We demonstrate the strong effect of the pairing blocking on the energies of γ-vibrational states. It is also shown that collectivity of γ-vibrational states is strictly determined by keeping the Nilsson selection rules in the corresponding lowest 2qp configurations.

  12. Hindered El Transitions in Eu155 and Tb161

    International Nuclear Information System (INIS)

    Malmskog, Sven G.

    1965-02-01

    The absolute E1 transition probabilities from the 3/2 + (411), 5/2 - (532) and 7/2 - (523) single particle levels in Eu 155 and Tb 161 have been measured by the method of delayed coincidences. This gave half lives of T 1/2 1/2 = (1.38 ± 0.06) ns for the 104.4 and 246 keV levels in Eu 155 . T 1/2 = (0.84 ± 0.04) ns and T 1/2 161 . The result has been compared with the calculations of a single particle in a deformed potential made by Nilsson

  13. Favored neutron excitations in superdeformed 147Gd

    International Nuclear Information System (INIS)

    Theisen, C.; Khadiri, N.; Vivien, J.P.; Ragnarsson, I.; Beausang, C.W.; Beck, F.A.; Belier, G.; Byrski, T.; Curien, D.; de France, G.; Disdier, D.; Duchene, G.; Finck, C.; Flibotte, S.; Gall, B.; Haas, B.; Hanine, H.; Herskind, B.; Kharraja, B.; Merdinger, J.C.; Nourreddine, A.; Nyako, B.M.; Perez, G.E.; Prevost, D.; Stezowski, O.; Rauch, V.; Rigollet, C.; Savajols, H.; Sharpey-Schafer, J.; Twin, P.J.; Wei, L.; Zuber, K.

    1996-01-01

    Four new superdeformed (SD) bands have been observed in 147 Gd using the EUROGAM II spectrometer. By comparison with 146,148,149 Gd SD bands, we use the effective alignment to assign excited band configurations, with the support of the Nilsson-Strutinsky cranking formalism. The effect of the crossing of the [642]5/2 and [651]1/2 neutron orbitals lying just below the magic N=86 SD shell gap has been investigated for the 146,147,148 Gd bands. Evidence for the [411]1/2 orbital is also given. copyright 1996 The American Physical Society

  14. Single Particle energy levels in ODD-A Nuclei

    International Nuclear Information System (INIS)

    Lasijo, R.S.

    1997-01-01

    Singe particle energies for atomic nuclei with odd-A number of nucleons, i.e. nuclei possessing odd number of protons or odd number of neutrons, were calculated based on Nilsson's theory, and then the diagrams were made. the energy diagram is in the from of plot of energies as function of deformations, entities identifying the deviations from the spherical shape. The energy calculations were done using FORTRAN 77 language of PC (Personal Computer) version with Microsoft Fortran Power Station compiler, which was then combined with WORD version 6.0 and EXCEL version 5.0 of WINDOWS WORKGROUP to make the plot

  15. Neutron-induced fission of uranium isotopes up to 100 MeV

    International Nuclear Information System (INIS)

    Lestone, J.P.; Gavron, A.

    1994-01-01

    The statistical-model description of the neutron-induced fission of U isotopes has been developed using densities of intrinsic states and spin cutoff parameters obtained directly from appropriate Nilsson model single-particle levels. The first-chance fission cross sections are reproduced well when the rotational contributions to the nuclear level densities are taken into account. In order to fit the U(n,f) cross sections above the threshold of second-chance fission, we must: (1) assume that the triaxial level-density enhancement is washed out at an excitation energy of approximately 7 MeV above the triaxial barriers with a width of approximately 1 MeV, implying a γ deformation for the first barriers where 10<γ<20 degree, and (2) include preequilibrium particle emission in the calculations. Above an incoming-neutron kinetic energy of approximately 17 MeV, our statistical model U(n,f) of cross sections increasingly overestimates the experimental data. This is not surprising since, at these high energies, little data exist on the scattering of neutrons to help guide the choice of optical-model parameters. A satisfactory reproduction of all of the available U(n,f) cross sections above 17 MeV is obtained by scaling our calculated compound-nucleus formation cross sections. This scaling factor falls from 1.0 at 17 MeV to 0.82 at 100 MeV

  16. Absolute M1 and E2 Transition Probabilities in 2{sup 33}U

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, S G; Hoejeberg, M

    1967-08-15

    Using the delayed coincidence technique, the following half lives have been determined for different excited states in {sup 233}U: T{sub 1/2} (311.9 keV level) = (1.20 {+-} 0.15) x 10{sup -10} sec, T{sub 1/2} (340.5 keV level) = (5.2 {+-} 1.0) x 10{sup -11} sec, T{sub 1/2} (398.6 keV level) = (5.5 {+-} 2.0) x 10{sup -11} sec and T{sub 1/2} (415.8 keV level) < 3 x 10{sup -11}sec. From these half life determinations, together with earlier known electron intensities and conversion coefficients, 22 reduced B(Ml) and B(E2) transition probabilities (including 9 limits) have been deduced. The rotational transitions give information on the parameters {delta} and (g{sub K} - g{sub R}) . The experimental M1 and E2 transition rates between members of different bands have been analysed in terms of the predictions of the Nilsson model, taking also pairing correlations and Coriolis coupling effects into account.

  17. Shell structures and chaos in nuclei and large metallic clusters

    International Nuclear Information System (INIS)

    Heiss, W.D.; University of the Witwatersrand, Johannesburg; Nazmitdinov, R.G.; Radu, S.; University of the Witwatersrand, Johannesburg

    1995-01-01

    A reflection-asymmetric deformed oscillator potential is analyzed from the classical and quantum mechanical point of view. The connection between occurrence of shell structures and classical periodic orbits is studied using the ''removal of resonances method'' in a classical analysis. In this approximation, the effective single particle potential becomes separable and the frequencies of the classical trajectories are easily determined. It turns out that the winding numbers calculated in this way are in good agreement with the ones found from the corresponding quantum mechanical spectrum using the particle number dependence of the fluctuating part of the total energy. When the octupole term is switched on it is found that prolate shapes are stable against chaos and can exhibit shells where spherical and oblate cases become chaotic. An attempt is made to explain this difference in the quantum mechanical context by looking at the distribution of exceptional points which results from the matrix structure of the respective Hamiltonians. In a similar way we analyze the modified Nilsson model and discuss its consequences for metallic clusters. (orig.)

  18. Decay of mass-separated 187Au (8.4 min) to 187Pt

    International Nuclear Information System (INIS)

    Gnade, B.E.; Fink, R.W.; Wood, J.L.

    1983-01-01

    The decay of 187 Au to 187 Pt has been studied with mass-separated sources from the UNISOR facility. Multiscaled spectra of γ-rays, X-rays, and conversion electrons, as well as γγt, Xγt, eγt, and eXt coincidences were obtained. The half-life of the 187 Au ground state was measured to be 8.4 +- 0.3 min. A decay scheme has been constructed incorporating 88% of the decay intensity assigned to 187 Au. The isub(13/2) band in 187 Pt is populated through low-spin band members. The levels at 260 and 288 keV are found to de-excite by EO transitions. From a γ-ray-gated K/β + ratio, the β-decay energy of 8.4 min 187 Au is deduced to be Qsub(EC)=3.90 +- 0.15 MeV. The positive-parity states in 187 Pt are compared with calculations made using the Nilsson model with a triaxial degree of freedom. The possibility that shape coexistence is present at low energy in 187 Pt is discussed. (orig.)

  19. Inorganic Arsenic–Related Changes in the Stromal Tumor Microenvironment in a Prostate Cancer Cell–Conditioned Media Model

    Science.gov (United States)

    Shearer, Joseph J.; Wold, Eric A.; Umbaugh, Charles S.; Lichti, Cheryl F.; Nilsson, Carol L.; Figueiredo, Marxa L.

    2015-01-01

    Background: The tumor microenvironment plays an important role in the progression of cancer by mediating stromal–epithelial paracrine signaling, which can aberrantly modulate cellular proliferation and tumorigenesis. Exposure to environmental toxicants, such as inorganic arsenic (iAs), has also been implicated in the progression of prostate cancer. Objective: The role of iAs exposure in stromal signaling in the tumor microenvironment has been largely unexplored. Our objective was to elucidate molecular mechanisms of iAs-induced changes to stromal signaling by an enriched prostate tumor microenvironment cell population, adipose-derived mesenchymal stem/stromal cells (ASCs). Results: ASC-conditioned media (CM) collected after 1 week of iAs exposure increased prostate cancer cell viability, whereas CM from ASCs that received no iAs exposure decreased cell viability. Cytokine array analysis suggested changes to cytokine signaling associated with iAs exposure. Subsequent proteomic analysis suggested a concentration-dependent alteration to the HMOX1/THBS1/TGFβ signaling pathway by iAs. These results were validated by quantitative reverse transcriptase–polymerase chain reaction (RT-PCR) and Western blotting, confirming a concentration-dependent increase in HMOX1 and a decrease in THBS1 expression in ASC following iAs exposure. Subsequently, we used a TGFβ pathway reporter construct to confirm a decrease in stromal TGFβ signaling in ASC following iAs exposure. Conclusions: Our results suggest a concentration-dependent alteration of stromal signaling: specifically, attenuation of stromal-mediated TGFβ signaling following exposure to iAs. Our results indicate iAs may enhance prostate cancer cell viability through a previously unreported stromal-based mechanism. These findings indicate that the stroma may mediate the effects of iAs in tumor progression, which may have future therapeutic implications. Citation: Shearer JJ, Wold EA, Umbaugh CS, Lichti CF, Nilsson CL

  20. High resolution gamma-ray spectroscopy and the fascinating angular momentum realm of the atomic nucleus

    International Nuclear Information System (INIS)

    Riley, M A; Simpson, J; Paul, E S

    2016-01-01

    In 1974 Aage Bohr and Ben Mottelson predicted the different ‘phases’ that may be expected in deformed nuclei as a function of increasing angular momentum and excitation energy all the way up to the fission limit. While admitting their picture was highly conjectural they confidently stated ‘...with the ingenious experimental approaches that are being developed, we may look forward with excitement to the detailed spectroscopic studies that will illuminate the behaviour of the spinning quantised nucleus’ . High resolution gamma-ray spectroscopy has indeed been a major tool in studying the structure of atomic nuclei and has witnessed numerous significant advances over the last four decades. This article will select highlights from investigations at the Niels Bohr Institute, Denmark, and Daresbury Laboratory, UK, in the late 1970s and early 1980s, some of which have continued at other national laboratories in Europe and the USA to the present day. These studies illustrate the remarkable diversity of phenomena and symmetries exhibited by nuclei in the angular momentum–excitation energy plane that continue to surprise and fascinate scientists. (invited comment)

  1. High resolution gamma-ray spectroscopy and the fascinating angular momentum realm of the atomic nucleus

    Science.gov (United States)

    Riley, M. A.; Simpson, J.; Paul, E. S.

    2016-12-01

    In 1974 Aage Bohr and Ben Mottelson predicted the different ‘phases’ that may be expected in deformed nuclei as a function of increasing angular momentum and excitation energy all the way up to the fission limit. While admitting their picture was highly conjectural they confidently stated ‘...with the ingenious experimental approaches that are being developed, we may look forward with excitement to the detailed spectroscopic studies that will illuminate the behaviour of the spinning quantised nucleus’. High resolution gamma-ray spectroscopy has indeed been a major tool in studying the structure of atomic nuclei and has witnessed numerous significant advances over the last four decades. This article will select highlights from investigations at the Niels Bohr Institute, Denmark, and Daresbury Laboratory, UK, in the late 1970s and early 1980s, some of which have continued at other national laboratories in Europe and the USA to the present day. These studies illustrate the remarkable diversity of phenomena and symmetries exhibited by nuclei in the angular momentum-excitation energy plane that continue to surprise and fascinate scientists.

  2. Definition of the Bacillus subtilis PurR operator using genetic and bioinformatic tools and expansion of the PurR regulon with glyA, guaC, pbuG, xpt-pbuX, yqhZ-folD, and pbuO

    DEFF Research Database (Denmark)

    Saxild, Hans Henrik; Brunstedt, K.; Nielsen, K.I.

    2001-01-01

    The expression of the pur operon, which encodes enzymes of the purine biosynthetic pathway in Bacillus subtilis, is subject to control by the purR gene product (PurR) and phosphoribosylpyrophosphate. This control is also exerted on the purA and purR genes. A consensus sequence for the binding...... of PurR, named the PurBox, has been suggested (M. Kilstrup, S.G. Jessing, S.B. Wichmand-Jorgensen, M. Madsen, and D. Nilsson, J. Bacteriol. 180:3900-3906, 1998). To determine whether the expression of other genes might be regulated by PurR, we performed a search for PurBox sequences in the B. subtilis...

  3. Säg något intressant! : En kvalitativ studie av marknadskommunikation på Facebook

    OpenAIRE

    Johansson, Elin; Johansson, Hanna; Nilsson, Camilla

    2011-01-01

    ABSTRACT Elin Johansson, Hanna Johansson, Camilla Nilsson Say something interesting! A qualitative study of marketing communication on Facebook                               Pages: 36 With the emergence of social media, new ways has been created for companies to reach out to its audience. From being dependent on journalists to provide information, companies today have the ability to self-publish information in the open media channels. The use of social media should not replace traditional mar...

  4. Off-shell superspace D=10 super Yang-Mills from covariantly quantized Green-Schwarz superstring

    International Nuclear Information System (INIS)

    Nissimov, E.; Pacheva, S.; Solomon, S.

    1988-05-01

    We construct a gauge invariant superspace action in terms of unconstrained off-shell superfields for the D=10 supersymmetric Yang-Mills (SYM) theory. We use to this effect the point particle limit of the BRST charge of the covariantly quantized harmonic Green-Schwarz superstring and a general covariant action principle for overdetermined systems of nonlinear field equations of motion. One obtains gauge and super Poincare invariant equations of motion equivalent to the Nilsson's constraints for D=10 SYM. In the previous approaches (light-cone-gauge, component-fields) one would have to sacrifice either explicit Lorenz invariance or explicit supersymmetry while in the present approach they are both manifest. (authors)

  5. Evidence of nontermination of collective rotation near the maximum angular momentum in Rb75

    Science.gov (United States)

    Davies, P. J.; Afanasjev, A. V.; Wadsworth, R.; Andreoiu, C.; Austin, R. A. E.; Carpenter, M. P.; Dashdorj, D.; Finlay, P.; Freeman, S. J.; Garrett, P. E.; Görgen, A.; Greene, J.; Grinyer, G. F.; Hyland, B.; Jenkins, D. G.; Johnston-Theasby, F. L.; Joshi, P.; Macchiavelli, A. O.; Moore, F.; Mukherjee, G.; Phillips, A. A.; Reviol, W.; Sarantites, D.; Schumaker, M. A.; Seweryniak, D.; Smith, M. B.; Svensson, C. E.; Valiente-Dobon, J. J.; Ward, D.

    2010-12-01

    Two of the four known rotational bands in Rb75 were studied via the Ca40(Ca40,αp)Rb75 reaction at a beam energy of 165 MeV. Transitions were observed up to the maximum spin Imax of the assigned configuration in one case and one-transition short of Imax in the other. Lifetimes were determined using the residual Doppler shift attenuation method. The deduced transition quadrupole moments show a small decrease with increasing spin, but remain large at the highest spins. The results obtained are in good agreement with cranked Nilsson-Strutinsky calculations, which indicate that these rotational bands do not terminate, but remain collective at Imax.

  6. Intrinsic states and rotational bands in 177Pt

    International Nuclear Information System (INIS)

    Dracoulis, G.D.; Fabricius, B.; Bark, R.A.; Stuchbery, A.E.; Popescu, D.G.; Kibedi, T.

    1989-11-01

    The 149 Sm ( 32 S,4n) 177 Pt reaction has been used to populate excited states in the neutron-deficient nucleus 177 Pt. Rotational bands based on intrinsic states assigned to the 1/2-[521], 5/2-[521] and (mixed) 7/2+ [633] Nilsson configurations have been observed. In contrast to the neighbou-ring even isotope 176 Pt, anomalies attributed to shape co-existence at low spin have not been observed. Implications for the deformation of 177 Pt are discussed together with the systematics of intrinsic states in this region, and alignments and other properties of N=99 nuclei. 37 refs., 15 figs., 3 tabs

  7. Internal bremsstrahlung spectra of the allowed. beta. emitters /sup 32/P, /sup 35/S and /sup 45/Ca

    Energy Technology Data Exchange (ETDEWEB)

    Powar, M S; Singh, M [Punjabi Univ., Patiala (India). Dept. of Physics

    1976-01-01

    A study of Coulomb field effects in internal bremsstrahlung (IB) has been undertaken by measuring the IB spectra for the allowed beta emitters /sup 32/P, /sup 35/S and /sup 45/Ca in the photon energy intervals of 50 to 1600 keV, 25 to 150 keV and 30 to 240 keV respectively. The experimental results show increasing positive departures from the KUB and Coulomb-corrected theories of Lewis and Ford, and Nilsson, with decreasing beta end-point energy. In the case of /sup 35/S the experimental results are 40 % higher than the more exact theory of Struzynski and Pollock for this isotope.

  8. Fine structure in deformed proton emitting nuclei

    International Nuclear Information System (INIS)

    Sonzogni, A. A.; Davids, C. N.; Woods, P. J.; Seweryniak, D.; Carpenter, M. P.; Ressler, J. J.; Schwartz, J.; Uusitalo, J.; Walters, W. B.

    1999-01-01

    In a recent experiment to study the proton radioactivity of the highly deformed 131 Eu nucleus, two proton lines were detected. The higher energy one was assigned to the ground-state to ground-state decay, while the lower energy, to the ground-state to the 2 + state decay. This constitutes the first observation of fine structure in proton radioactivity. With these four measured quantities, proton energies, half-life and branching ratio, it is possible to determine the Nilsson configuration of the ground state of the proton emitting nucleus as well as the 2 + energy and nuclear deformation of the daughter nucleus. These results will be presented and discussed

  9. Neutron induced fission of U isotopes up to 100 MeV

    International Nuclear Information System (INIS)

    Lestone, J.P.; Gavron, A.

    1993-01-01

    We have developed a statistical model description of the neutron induced fission of U isotopes using densities of intrinsic states and spin cut off parameters obtained directly from appropriate Nilsson model single particle levels. The first chance fission cross sections are well reproduced when the rotational contributions to the nuclear level densities are taken into account. In order to fit the U(n,f) cross sections above the threshold of second chance fission, we need to: (1) assume that the triaxial level density enhancement is washed out at an excitation energy of ∼7 MeV above the triaxial barriers with a width of ∼1 MeV, implying a γ deformation for the first barriers of 10 degree < γ < 20 degree; and (2) include pre-equilibrium particle emission in the calculations. Above an incoming neutron kinetic energy of ∼17 MeV our statistical model U(n,f) cross sections increasingly overestimate the experimental data when so called ''good'' optical model potentials are used to calculate the compound nucleus formation cross sections. This is not surprising since at these high energies little data exists on the scattering of neutrons to help guide the choice of optical model parameters. A satisfactory reproduction of all the available U(n,f) cross sections above 17 MeV is obtained by a simple scaling of our calculated compound nucleus formation cross sections. This scaling factor falls from 1.0 at 17 MeV to 0.82 at 100 MeV

  10. Multi-quasiparticle high-K isomeric states in deformed nuclei

    Directory of Open Access Journals (Sweden)

    Xu F. R.

    2016-01-01

    Full Text Available In the past years, we have made many theoretical investigations on multi-quasiparticle high-K isomeric states. A deformation-pairing-configuration self-consistent calculation has been developed by calculating a configuration-constrained multi-quasiparticle potential energy surface (PES. The specific single-particle orbits that define the high-K configuration are identified and tracked (adiabatically blocked by calculating the average Nilsson numbers. The deformed Woods-Saxon potential was taken to give single-particle orbits. The configuration-constrained PES takes into account the shape polarization effect. Such calculations give good results on excitation energies, deformations and other structure information about multi-quasiparticle high-K isomeric states. Many different mass regions have been investigated.

  11. Multipole mixtures for (2γ+-2g+) transitions in nonspherical nuclei with N = 90-110

    International Nuclear Information System (INIS)

    Demidov, A.M.; Govor, L.I.; Kurkin, V.A.; Mikhajlov, I.V.

    1999-01-01

    The multipole mixture σ-sings for (2 γ + -2 g + ) transitions of nuclei with neutron number N = 90-110 are considered. It is found that the correlations of the σ-sings (σ γ + -2 g + ) and (4 γ + -4 g + ) transitions and also the anti-correlations of the σ-sings for (2 γ + -2 g + ) and (2 β + -2 g + ) transitions are observed in majority of cases. There are exclusions from these rules due to inter-cation between β- and γ-vibrational excitations, when they approach each other in energy, and as well due to the contribution given by the two-proton configuration of proton Nilsson orbits in the 2 γ + -level [ru

  12. An i{sub 13/2} neutron intruder band in {sup 141}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Mullins, S M; Omar, A; Persson, L; Prevost, D; Waddington, J C [McMaster Univ., Hamilton, ON (Canada); Andrews, H R; Ball, G C; Galindo-Uribarri, A; Janzen, V P; Radford, D C; Ward, D [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.; Drake, T E [Toronto Univ., ON (Canada). Dept. of Physics; Fossan, D B; Lafosse, D; Vaska, P; Waring, M [State Univ. of New York, Stony Brook, NY (United States). Dept. of Physics; Wadsworth, R [York Univ. (United Kingdom). Dept. of Physics

    1992-08-01

    The nucleus {sup 141}Gd has been investigated at high spins for the first time following the reactions {sup 112}Sn({sup 32}S,2pn){sup 141}Gd at 155 MeV and {sup 112}Sn({sup 33}S,2p2n){sup 141}Gd at 170 MeV. The methods of in-beam {gamma}-ray spectroscopy were used to establish a number of different structures, including a band which has been assigned as being based on the {nu}i{sub 13/2}[660]1/2{sup +} Nilsson intruder orbital. This is the heaviest nucleus thus far in which this type of intruder band has been identified. (author). 11 refs., 3 figs.

  13. Prolate dominant but oblate stable

    International Nuclear Information System (INIS)

    Girija, K.K.; Joseph, Antony

    2013-01-01

    This article discusses the yrast states of even-even nuclei in the isotopic chains 150-160 Dy, 150-160 Er and 150-160 Yb and thereby to study the shape and deformation dependence of ground state energy, exploring cranked Nilsson Strutinsky shell correction method and potential energy surface (PES) diagrams. The total energy calculations have been performed for the even-even nuclei of the isotopic chains 150-160 Dy, 150-160 Er and 150-160 Yb in the ground state. The range of triaxiality parameter used is 0-60 ° and a frequency range of 0-1.5 MeV is employed. The quadrupole deformation parameter ε 2 is varied from 0 to 1

  14. Do light nuclei display a universal γ-ray strength function?

    Directory of Open Access Journals (Sweden)

    Voinov A.

    2012-02-01

    Full Text Available In this work we focus on properties in the quasi-continuum of light nuclei. Generally, both level density and γ-ray strength function (γ-SF differ from nucleus to nucleus. In order to investigate this closer, we have performed particle-γ coincidences using the reactions (p, p', (p, d and (p, t on a 46Ti target. In particular, the very rich data set of the 46Ti(p, p'46Ti inelastic scattering reaction allows analysis of the coincidence data for many independent data sets. Using the Oslo method, we find one common level density for all data sets. If transitions to well-separated low-energy levels are included, the deduced γ-SF may change by a factor of 2 – 3, due strong to Porter-Thomas fluctuations. However, a universal γ-SF with small fluctuations is found provided that only excitation energies above 3 MeV are taken into account. The nuclear structure of the titaniums is discussed within a combinatorial quasi-particle model, showing that only few Nilsson orbitals participate in building up the level density for these light nuclei.

  15. Description of giant resonances

    International Nuclear Information System (INIS)

    Lane, A.M.

    1975-01-01

    The history of collective theories in nuclear physics is briefly reviewed. It is emphasised that some theories (like RPA) allow collectivity to emerge from calculations, while others (like GCM) essentially impose a collective framework from teh start. The former class has the incidental merit that it treats spreading of collective states arising from interaction with (discrete and continuum) particle excitations. A problem with the RPA calculations is that they are almost too detailed if one's interest is in exposing systematic qualitative features. The speaker (along with co-authors) has developed a sum-rule method for exposing such trends. It is based on the fact that one can readily evaluate three sum-rules; in addition to the familiar one with plus-one power of energy-weighting, those with minus-one and plus-three powers can be evaluated for RPA states in closed form. From the three moments, the energy and spread of the collective state can be obtained. Amongst other things, the approach gives a very simple derivation of the Suzuki-Mottelson result that collective energy equals √2 times the oscillator quantum. (orig.) [de

  16. Nuclear structure at the proton dripline

    International Nuclear Information System (INIS)

    Maglione, Enrico; Ferreira, Lidia S.; Costa Lopes, Miguel

    2007-01-01

    Recent studies with exotic nuclei far from the stability region, lead to the discovery of one and two proton radioactivity, from ground state of spherical, as well as deformed nuclei. Isomeric decay and fine structure were also measured, and in some cases, a prompt proton and alpha particle emission was observed. It was established that, the majority of prompt particle decays proceeds from superdeformed initial states, into spherical daughter states, revealing a change of deformation during the decay. Proton radioactivity has been the unique way to probe nuclear structure mechanisms in this region of stability. Since proton emitters lie beyond the proton drip-line, they also give the possibility of observing Nilsson resonances. In fact, the experimental data on proton radioactivity in regionswhere theoretical models predict a certain deformation for the nucleus is consistent with the idea that the proton was in a single particle resonance state, in the field of the daughter nucleus. An important aspect of such calculations is the inclusion of the nuclear structure properties of the core,like the rotational spectrum of the daughter nucleus, and the pairing residual interaction. We will address various questions concerning what we have learned from the data and how far our theoretical models have taken us in the region of neutron deficient nuclei at the borders of stability. (Author)

  17. Necked-in superdeformed nuclei

    International Nuclear Information System (INIS)

    Joensson, L.O.

    1997-03-01

    In this dissertation the possibility of forming superdeformed states related to two connected spheres, having a more or less pronounced neck, is investigated. Detailed Nilsson-Strutinsky calculations with the cranked Woods-Saxon potential and a finite-range liquid drop model are carried out in the 180 Hg region, where superdeformed states related to two overlapping 90 Zr are predicted. Detailed spectroscopic properties are calculated. The effect of the necking degree of freedom on the giant dipole resonance, GDR, is investigated. The calculations are carried out with the Woods-saxon potential for the single-particle states, and the random phase approximation formalism for the phonon states. The residual interaction and coupling constants are determined by requirements of transitional invariance. The lower energy component of the GDR spectrum for superdeformed shapes, corresponding to vibrations along the symmetry axis, is diminished with increasing necking, and the mean energy of the GDR is increased. The folded Yukawa-plus-exponential liquid drop models take into account the finite range of the nuclear force, which is important when elongated and necked-in nuclear shapes are considered. However, it is shown that they are unstable towards higher multipole deformations, and that unphysical shapes are obtained in free minimizations when too high multipole deformations are included. Limits on multipolarity are given as functions of mass number. 9 refs., 4 figs

  18. On the relation between the statistical γ-decay and the level density in 162Dy

    International Nuclear Information System (INIS)

    Henden, L.; Bergholt, L.; Guttormsen, M.; Rekstad, J.; Tveter, T.S.

    1994-12-01

    The level density of low-spin states (0-10ℎ) in 162 Dy has been determined from the ground state up to approximately 6 MeV of excitation energy. Levels in the excitation region up to 8 MeV were populated by means of the 163 Dy( 3 He, α) reaction, and the first-generation γ-rays in the decay of these states has been isolated. The energy distribution of the first-generation γ-rays provides a new source of information about the nuclear level density over a wide energy region. A broad peak is observed in the first-generation spectra, and the authors suggest an interpretation in terms of enhanced M1 transitions between different high-j Nilsson orbitals. 30 refs., 9 figs., 2 tabs

  19. Microscopic analysis of wobbling excitations in 156Dy and 162Yb

    International Nuclear Information System (INIS)

    Nazmitdinov, R. G.; Kvasil, J.

    2007-01-01

    In the cranked Nilsson-plus-random-phase approximation, we study low-lying quadrupole excitations of positive parity and negative signature in 156 Dy and 162 Yb at high spins. Special attention is paid to a consistent description of wobbling excitations and their identification among excited states. A good agreement between the available experimental data and the results of calculations is obtained. We find that the lowest odd-spin γ-vibrational states in 156 Dy transform into wobbling excitations after the backbending associated with the transition from an axially symmetric shape to a nonaxial shape. Similar results are predicted for 162 Yb. The analysis of electromagnetic transitions uniquely determines the sign of the γ deformation in both nuclei after the transition point

  20. Hindered El Transitions in Eu{sup 155} and Tb{sup 161}

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, Sven G

    1965-02-15

    The absolute E1 transition probabilities from the 3/2{sup +} (411), 5/2{sup -} (532) and 7/2{sup -} (523) single particle levels in Eu{sup 155} and Tb{sup 161} have been measured by the method of delayed coincidences. This gave half lives of T{sub 1/2} < 0.2 ns and T{sub 1/2} = (1.38 {+-} 0.06) ns for the 104.4 and 246 keV levels in Eu{sup 155}. T{sub 1/2} = (0.84 {+-} 0.04) ns and T{sub 1/2} < 0. 2 ns for the 417.6 and 480.6 keV levels in Tb{sup 161}. The result has been compared with the calculations of a single particle in a deformed potential made by Nilsson.

  1. First excited states in doubly-odd 110Sb: Smooth band termination in the A ∼ 110 region

    International Nuclear Information System (INIS)

    Lane, G.J.; Fossan, D.B.; Thorslund, I.

    1996-01-01

    Excited states have been identified for the first time in 110 Sb in a comprehensive series of γ-spectroscopy experiments, including recoil-mass and neutron-field measurements. Three high-spin decoupled bands with configurations based on 2p-2h excitations across the Z = 50 shell gap, are observed to show the features of smooth band termination, the first such observation in an odd-odd nucleus. The yrast intruder band has been connected to the low spin levels and is tentatively identified up to its predicred termination at I π = (45 + ). Detailed configuration assignments are made through comparison with configuration-dependent cranked Nilsson-Strutinsky calculations; excellent agreement with experiment is obtained. The systematic occurrence of smoothly terminating bands in the neighboring isotopes is discussed

  2. Description of rotating N=Z nuclei in terms of isovector pairing

    International Nuclear Information System (INIS)

    Afanasjev, A.V.; Frauendorf, S.

    2005-01-01

    A systematic investigation of the rotating N=Z even-even nuclei in the mass A=68-80 region has been performed within the frameworks of the cranked relativistic mean field, cranked relativistic Hartree-Bogoliubov theories, and cranked Nilsson-Strutinsky approach. Most of the experimental data are well accounted for in the calculations. The present study suggests the presence of strong isovector np pair field at low spin, whose strength is defined by the isospin symmetry. At high spin, the isovector pair field is destroyed and the data are well described by the calculations assuming zero pairing. No clear evidence for the existence of the isoscalar t=0 np pairing has been obtained in the present investigation performed at the mean field level

  3. BOOK REVIEW - Sieglinde Gstöhl and Simon Schunz (eds., Theorizing the European Neighbourhood Policy, Abingdon: Routledge, 2017

    Directory of Open Access Journals (Sweden)

    Cristian NITOIU

    2017-06-01

    Full Text Available Since its inception at the beginning of the 2000s, the approach of the European Union (EU towards its neighbourhood has been afforded significant attention by the academic literature. Many research projects and studies have presented significant empirical insights regarding the way the EU has developed its approach towards its southern and eastern neighbourhoods (Theuns 2017; Ademmer, Delcour, and Wolczuk 2016; Nilsson and Silander 2016; Edwards 2008; Bechev and Nicolaïdis 2010; Beauguitte, Richard, and Guérin-Pace 2015. At the same time, the success and effectiveness of the European Neighbourhood Policy (ENP has been debated and reviewed by official institutions, think tanks or scholars, with the EU almost always lagging behind its ambitious goals and commitments (Schumacher 2015.

  4. Yrast four-quasi-particle states in 182W

    International Nuclear Information System (INIS)

    Regan, P.H.; Walker, P.M.; Dracoulis, G.D.; Anderssen, S.S.; Byrne, A.P.; Davidson, P.M.; Kibedi, T.; Lane, G.J.; Stuchbery, A.E.; Yeung, K.C.

    1994-01-01

    High-spin states of the stable isotope 182 W have been studied using the reactions 176 Yb( 13 C,α3n) 182 W and 176 Yb( 9 Be,3n) 182 W at beam energies of 65 and 40 MeV, respectively. Three, possibly four, new intrinsic states at high spins have been observed corresponding to different high-K four-quasi-particle structures. The K π =15 + and 17 - levels have lifetimes of 78(15) and 25(10) ns, respectively. Rotational bands are observed built on the K π =16 + and 17 - yrast states. The coupling of Nilsson orbitals which give rise to high-K states at the yrast line and the K-forbiddenness of the K π =15 + isomeric decay are discussed. (orig.)

  5. In-beam study of {sup 253}No using the SAGE spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Mistry, A.K.; Herzberg, R.D.; Butler, P.A.; Cox, D.M.; Joss, D.T.; Page, R.D.; Seddon, D.; Thornhill, J.; Wells, D. [University of Liverpool, Oliver Lodge Laboratory, Liverpool (United Kingdom); Greenlees, P.T.; Papadakis, P.; Auranen, K.; Grahn, T.; Jakobsson, U.; Julin, R.; Konki, J.; Leino, M.; Pakarinen, J.; Peura, P.; Rahkila, P.; Sandzelius, M.; Scholey, C.; Sorri, J.; Stolze, S.; Uusitalo, J. [University of Jyvaskyla, Department of Physics, Jyvaskyla (Finland); Garnsworthy, A.B.; Ketelhut, S. [University of British Columbia, TRIUMF, Vancouver, British Columbia (Canada); Hauschild, K.; Lopez-Martens, A. [Universite Paris-Sud, CSNSM, CNRS, IN2P3, Orsay (France); Simpson, J. [STFC, Daresbury Laboratory, Daresbury, Warrington (United Kingdom)

    2017-02-15

    The heavy actinide nucleus {sup 253}No (Z = 102) was studied using the (S)ilicon (A)nd (Ge)rmanium (SAGE) spectrometer allowing simultaneous in-beam γ-ray and conversion electron spectroscopy at the accelerator laboratory of the University of Jyvaeskylae. Using the recoil-tagging technique, γ-electron coincidences have allowed for the extension of the level scheme in the lower-spin region of the yrast band. In addition, internal conversion coefficient (ICC) measurements to establish the multipolarity of transitions have been performed. Measurement of the interband-intraband branching ratios supports the assignment of the Nilsson band-head configuration 9/2{sup -}[734] assigned in previous studies. The study shows the viability of combined in-beam electron and γ-ray spectroscopy down to μb cross sections. (orig.)

  6. Energy of the 4(+) isomer and new bands in the odd-odd nucleus 74Br

    International Nuclear Information System (INIS)

    Doering, J.; Holcomb, J.W.; Johnson, T.D.; Riley, M.A.; Tabor, S.L.; Womble, P.C.; Winter, G.

    1993-01-01

    High-spin states of the odd-odd nucleus 74 Br were investigated via the reactions 58 Ni ( 19 F,2pn) 74 Br and 65 Cu( 12 C,3n) 74 Br at beam energies of 62 and 50 MeV, respectively. On the basis of coincidence data new levels have been introduced and partly grouped into rotational bands. Some of these new states decay to known levels of negative-parity bands built on both the ground state and the long-lived 4 (+) isomer. Thus, an excitation energy of 13.8 keV has been deduced for the long-lived isomer in 74 Br. The level sequences observed are interpreted in terms of Nilsson configurations in conjunction with collective excitations

  7. Bioreactors for Tissue Engineering of Cartilage

    Science.gov (United States)

    Concaro, S.; Gustavson, F.; Gatenholm, P.

    The cartilage regenerative medicine field has evolved during the last decades. The first-generation technology, autologous chondrocyte transplantation (ACT) involved the transplantation of in vitro expanded chondrocytes to cartilage defects. The second generation involves the seeding of chondrocytes in a three-dimensional scaffold. The technique has several potential advantages such as the ability of arthroscopic implantation, in vitro pre-differentiation of cells and implant stability among others (Brittberg M, Lindahl A, Nilsson A, Ohlsson C, Isaksson O, Peterson L, N Engl J Med 331(14):889-895, 1994; Henderson I, Francisco R, Oakes B, Cameron J, Knee 12(3):209-216, 2005; Peterson L, Minas T, Brittberg M, Nilsson A, Sjogren-Jansson E, Lindahl A, Clin Orthop (374):212-234, 2000; Nagel-Heyer S, Goepfert C, Feyerabend F, Petersen JP, Adamietz P, Meenen NM, et al. Bioprocess Biosyst Eng 27(4):273-280, 2005; Portner R, Nagel-Heyer S, Goepfert C, Adamietz P, Meenen NM, J Biosci Bioeng 100(3):235-245, 2005; Nagel-Heyer S, Goepfert C, Adamietz P, Meenen NM, Portner R, J Biotechnol 121(4):486-497, 2006; Heyland J, Wiegandt K, Goepfert C, Nagel-Heyer S, Ilinich E, Schumacher U, et al. Biotechnol Lett 28(20):1641-1648, 2006). The nutritional requirements of cells that are synthesizing extra-cellular matrix increase along the differentiation process. The mass transfer must be increased according to the tissue properties. Bioreactors represent an attractive tool to accelerate the biochemical and mechanical properties of the engineered tissues providing adequate mass transfer and physical stimuli. Different reactor systems have been [5] developed during the last decades based on different physical stimulation concepts. Static and dynamic compression, confined and nonconfined compression-based reactors have been described in this review. Perfusion systems represent an attractive way of culturing constructs under dynamic conditions. Several groups showed increased matrix

  8. Scissors and unique-parity modes of M1 excitation in deformed nuclei

    International Nuclear Information System (INIS)

    Otsuka, T.

    1989-01-01

    In this paper the possible modes of M1 excitation in deformed even-even nuclei are studied in terms of the particle-number-conserved Nilsson + BCS formalism with the standard parameters. The spurious motion with respect to the rotation is removed. In addition to the Scissors mode, the Unique-Parity Spin and Normal-Parity Spin modes are suggested, although the latter may be fragmented to a large extent. The Scissors mode carries most of the orbital strength, while the others the spin strength. The proton Unique-Parity (i.e. Oh 11/12 ) Spin mode for 164 Dy is obtained just below Ex = 3 MeV with B(M1) ∼ 0.2 μ 2 N ) in the sum rule limit. This is in a good agreement to the recent experimental data

  9. Search for shape coexistence in {sup 188,190}Pb via fine structure in the alpha decay of {sup 192,194}Po

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I.; Davids, C.; Janssens, R.V.F. [and others

    1995-08-01

    The interaction between coexisting shapes in nuclei near closed shells was of great interest in the past decade. Excited 0{sup +} states at low energy can often be identified as the bandheads of structures with differing shapes built on those states, These structures were identified in {sup 190-198}Pb via beta decay and alpha decay {open_quotes}fine structure{close_quotes} studies. Coexistence of different shapes in Pb nuclei was predicted by Nilsson-Strutinsky calculations, in which both the oblate and prolate minima were predicted to have excitation energies near 1 MeV. It was our intention to continue the systematic study of the Pb nuclides by searching for excited O{sup +} states in {sup 188}Pb by observing the fine structure in the alpha decay of {sup 192}Po.

  10. TALENT MANAGEMENT – TOWARDS THE NEW PERSPECTIVES

    Directory of Open Access Journals (Sweden)

    Dana Egerová

    2014-10-01

    Full Text Available Talent management has become one of the most important issues in organizations and one of the most debated themes in human resource management theory in recent years. The increasing attention to talent is affected by factors such as globalization, knowledge-based competition, changing the world of work, new forms of organizations and demographic changes. Organizations are nowadays becoming increasingly aware of the strategic value of talent and the impact of strong talent on their competitiveness on the global market. Talent is becoming recognised as a core competitive asset in business organizations (Silzer and Dowell, 2010. It has become clear that future competitiveness and prosperity of an organization depend strongly on the company’s ability to manage its talents effectively (Nilsson and Ellstrőm, 2012.

  11. High spin spectroscopy for A ∼ 160 nuclei

    International Nuclear Information System (INIS)

    Yu, C.-H.

    1989-01-01

    Experimental routhians, alignments, band crossing frequencies, and the B(M1)/B(E2) ratios of the N = 90 isotopes and several light Lu (N = 90--96) isotopes are summarized and discussed in terms of shape changes. These systematic analyses show a neutron and proton number dependent deformations (both quadruple and γ deformations) for these light rare earth nuclei. The stability of the nuclear deformation with respect to β and γ is also found to be particle number dependent. Such particle number dependent shapes can be attributed to the different locations of the proton and neutron Fermi levels in the Nilsson diagrams. Configurations dependent shapes are discussed specially concerned the deformation difference between the proton h 9/2 1/2 - [541] and the high-K h 11/2 configurations. The observed large neutron band crossing frequencies in the h 9/2 1/2 - [541] configuration support the predicted large deformation of this configuration but can be reproduced by the cranked shell model calculation according to the predicted deformations. Lifetime measurement for 157 Ho, one of the nuclei that show a large ℎω c in the 1/2 - [541] band, indicates that deformation difference can only account for 20% of such shift in ℎω c . 55 refs., 12 figs

  12. New level schemes with high-spin states of 105,107,109Tc

    International Nuclear Information System (INIS)

    Luo, Y.X.; Rasmussen, J.O.; Lee, I.Y.; Fallon, P.; Hamilton, J.H.; Ramayya, A.V.; Hwang, J.K.; Gore, P.M.; Zhu, S.J.; Wu, S.C.; Ginter, T.N.; Ter-Akopian, G.M.; Daniel, A.V.; Stoyer, M.A.; Donangelo, R.; Gelberg, A.

    2004-01-01

    New level schemes of odd-Z 105,107,109 Tc are proposed based on the 252 Cf spontaneous-fission-gamma data taken with Gammasphere in 2000. Bands of levels are considerably extended and expanded to show rich spectroscopic information. Spin/parity and configuration assignments are made based on determinations of multipolarities of low-lying transitions and the level analogies to the previously reported levels, and to those of the neighboring Rh isotopes. A non-yrast negative-parity band built on the 3/2 - [301] orbital is observed for the first time in 105 Tc. A positive-parity band built on the 1/2 + [431] intruder orbital originating from the π(g 7/2 /d 5/2 ) subshells and having a strong deformation-driving effect is observed for the first time in 105 Tc, and assigned in 107 Tc. A positive-parity band built on the excited 11/2 + level, which has rather low excitation energy and predominantly decays into the 9/2 + level of the ground state band, provides evidence of triaxiality in 107,109 Tc, and probably also in 105 Tc. Rotational constants are calculated and discussed for the K=1/2 intruder bands using the Bohr-Mottelson formula. Level systematics are discussed in terms of the locations of proton Fermi levels and deformations. The band crossings of yrast positive-parity bands are observed, most likely related to h 11/2 neutron alignment. Triaxial-rotor-plus-particle model calculations performed with ε=0.32 and γ=-22.5 deg. on the prolate side of maximum triaxiality yielded the best reproduction of the excitation energies, signature splittings, and branching ratios of the positive-parity bands (except for the intruder bands) of these Tc isotopes. The significant discrepancies between the triaxial-rotor-plus-particle model calculations and experiment for the K=1/2 intruder bands in 105,107 Tc need further theoretical studies

  13. Validity of single term energy expression for ground state rotational band of even-even nuclei

    International Nuclear Information System (INIS)

    Sharma, S.; Kumar, R.; Gupta, J.B.

    2005-01-01

    Full text: There are large numbers of empirical studies of gs band of even-even nuclei in various mass regions. The Bohr-Mottelson's energy expression is E(I) = AX + BX 2 +CX 3 +... where X = I(I+1). The anharmonic vibrator energy expression is: E(I) = al + bl 2 + cl 3 SF model with energy expression: E(I)= pX + qI + rXI... where the terms represents the rotational, vibrational and R-V interaction energy, respectively. The validity f the various energy expressions with two terms had been tested by Sharma for light, medium and heavy mass regions using R I s. R 4 plots (where, spin I=6, 8, 10, 12), which are parameter independent. It was also noted, that of the goodness of energy expression can be judged with the minimum input of energies (i.e. only 2 parameters) and predictability's of the model p to high spins. Recently, Gupta et. al proposed a single term energy expression (SSTE) which was applied for rare earth region. This proposed power law reflected the unity of rotation - vibration in a different way and was successful in explaining the structure of gs-band. It will be useful for test the single term energy expression for light and heavy mass region. The single term expression for energy of ground state band can be written as: E I =axI b , where the index b and the coefficient a are the constant for the band. The values of b+1 and a 1 are as follows: b 1 =log(R 1 )/log(I/2) and a 1 =E I /I b ... The following results were gained: 1) The sharp variation in the value of index b at given spin will be an indication of the change in the shape of the nucleus; 2) The value of E I /I b is fairly constant with spin below back-bending, which reflects the stability of shape with spin; 3) This proposed power law is successful in explaining the structure of gs-band of nuclei

  14. Narratives about music and health

    DEFF Research Database (Denmark)

    Uddholm, Mats; Nilsson, Bo

    involving music therapists or music educators, such as: with clients, students, children, elder people; among nurses, deacons, social workers, preschools teachers or care assistants. The field of Music and Health is not necessarily about illness or care, but can as well be understood as an aspect of quality......Narratives about music and health Dr Bo Nilsson, Kristianstad University, Sweden Dr Mats Uddholm, University College Nordjylland, Denmark Music is used in many professional contexts that are not associated with music therapy or music education in a traditional sense. How do professionals...... in different contexts use music and how do they describe their thoughts about music in their professional work? Those are the main questions in our study focusing on narratives about music and health in professional relations. In a pilot study six strategically chosen participants from Sweden and Denmark...

  15. Boreonectes gen. n., a new genus for the Stictotarsus griseostriatus (De Geer group of sibling species (Coleoptera: Dytiscidae, with additional karyosystematic data on the group

    Directory of Open Access Journals (Sweden)

    Robert Angus

    2010-12-01

    Full Text Available A new genus, Boreonectes gen. n., is erected for the seven S. griseostriatus-group  species  as  well  as eight other American ones listed by Nilsson and Angus (1992 as comprising the Stictotarsus griseostriatus-group as DNA work by Ribera (2003 shows this arrangement to be untenable, and no other genus-group name has been found to be available. Chromosomal investigations have shown that B. griseostriatus (De Geer, 1774 occurs as far west as the Little St Bernard Pass in the Alps, with B. alpestris (Dutton et Angus, 2007 in the Italian Gran Paradiso National Park to the south of this. B. multilineatus (Falkenström, 1922 is recorded from the Pyrenees for the first time, and B. ibericus (Dutton et Angus, 2007 is shown to be present in the Moyen Atlas of Morocco.

  16. Potent neutralizing serum immunoglobulin A (IgA) in human immunodeficiency virus type 2-exposed IgG-seronegative individuals

    DEFF Research Database (Denmark)

    Lizeng, Q; Nilsson, C; Sourial, S

    2004-01-01

    Links Potent neutralizing serum immunoglobulin A (IgA) in human immunodeficiency virus type 2-exposed IgG-seronegative individuals.Lizeng Q, Nilsson C, Sourial S, Andersson S, Larsen O, Aaby P, Ehnlund M, Bjorling E. Research Center, South Hospital, Stockholm, Sweden. The mechanisms behind...... the resistance to human immunodeficiency virus type 2 (HIV-2) infection are still not fully understood. In the present study, we explored the HIV-2-specific humoral serum immunoglobulin A (IgA) immune response in HIV-2-exposed IgG-seronegative (EGSN) individuals. Serum samples from heterosexual EGSN individuals...... and their known HIV-2-infected partners, as well as controls originating from Guinea-Bissau in Africa, were studied. Antibody reactivity to native and recombinant envelope glycoproteins was investigated, and the capacity of purified serum IgA to neutralize HIV-2(SBL6669) was tested. Our results showed that 16...

  17. Deformation and shape coexistence in medium mass nuclei

    International Nuclear Information System (INIS)

    Meyer, R.A.

    1985-01-01

    Emerging evidence for deformed structures in medium mass nuclei is reviewed. Included in this review are both nuclei that are ground state symmetric rotors and vibrational nuclei where there are deformed structures at excited energies (shape coexistence). For the first time, Nilsson configurations in odd-odd nuclei within the region of deformation are identified. Shape coexistence in nuclei that abut the medium mass region of deformation is also examined. Recent establishment of a four-particle, four-hole intruder band in the double subshell closure nucleus 96 Zr 56 is presented and its relation to the nuclear vibron model is discussed. Special attention is given to the N=59 nuclei where new data have led to the reanalysis of 97 Sr and 99 Zr and the presence of the [404 9/2] hole intruder state as isomers in these nuclei. The low energy levels of the N=59 nuclei from Z=38 to 50 are compared with recent quadrupole-phonon model calculations that can describe their transition from near-rotational to single closed shell nuclei. The odd-odd N=59 nuclei are discussed in the context of coexisting shape isomers based on the (p[303 5/2]n[404 9/2])2 - configuration. Ongoing in-beam (t,p conversion-electron) multiparameter measurements that have led to the determination of monopole matrix elements for even-even 42 Mo nuclei are presented, and these are compared with initial estimates using IBA-2 calculations that allow mixing of normal and cross subshell excitations. Lastly, evidence for the neutron-proton 3 S 1 force's influence on the level structure of these nuclei is discussed within the context of recent quadrupole-phonon model calculations. (Auth.)

  18. Enactment effects and integration processes in younger and older adults' memory for actions.

    Science.gov (United States)

    Feyereisen, Pierre

    2009-05-01

    The positive effects of gesturing on memory are robust but their interpretation is still controversial. To clarify the issue, recognition and cued recall of action phrases were compared in 24 younger (M=20 years) and 20 older adults (M=68 years), in three encoding conditions--purely verbal tasks (VTs), subject-performed tasks (SPTs), and experimenter-performed tasks (EPTs)--for well- and poorly integrated phrases. As expected, the effects of these factors were significant, but there was no interaction between age-related differences, enactment effects, and semantic association. In particular, both SPT and EPT displayed similar advantages over VT conditions in both age groups and in the two memory tasks. These results are discussed in relation to the debate between Engelkamp on one side, and Kormi-Nouri and Nilsson on the other side, about the role of motor components in the episodic integration of verbs and nouns in action phrases.

  19. Transition questions in clinical practice - validity and reproducibility

    DEFF Research Database (Denmark)

    Lauridsen, Henrik Hein

    2008-01-01

    Transition questions in CLINICAL practice - validity and reproducibility Lauridsen HH1, Manniche C3, Grunnet-Nilsson N1, Hartvigsen J1,2 1   Clinical Locomotion Science, Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark. e-mail: hlauridsen......@health.sdu.dk 2   Nordic Institute of Chiropractic and Clinical Biomechanics, Part of Clinical Locomotion Science, Odense, Denmark 3   Backcenter Funen, Part of Clinical Locomotion Science, Ringe, Denmark   Abstract  Understanding a change score is indispensable for interpretation of results from clinical studies...... are reproducible in patients with low back pain and/or leg pain. Despite critique of several biases, our results have reinforced the construct validity of TQ’s as an outcome measure since only 1 hypothesis was rejected. On the basis of our findings we have outlined a proposal for a standardised use of transition...

  20. Nuclear Structure in China 2010

    Science.gov (United States)

    Bai, Hong-Bo; Meng, Jie; Zhao, En-Guang; Zhou, Shan-Gui

    2011-08-01

    Personal view on nuclear physics research / Jie Meng -- High-spin level structures in [symbol]Zr / X. P. Cao ... [et al.] -- Constraining the symmetry energy from the neutron skin thickness of tin isotopes / Lie-Wen Chen ... [et al.] -- Wobbling rotation in atomic nuclei / Y. S. Chen and Zao-Chun Gao -- The mixing of scalar mesons and the possible nonstrange dibaryons / L. R. Dai ... [et al.] -- Net baryon productions and gluon saturation in the SPS, RHIC and LHC energy regions / Sheng-Qin Feng -- Production of heavy isotopes with collisions between two actinide nuclides / Z. Q. Feng ... [et al.] -- The projected configuration interaction method / Zao-Chun Gao and Yong-Shou Chen -- Applications of Nilsson mean-field plus extended pairing model to rare-earth nuclei / Xin Guan ... [et al.] -- Complex scaling method and the resonant states / Jian-You Guo ... [et al.] -- Probing the equation of state by deep sub-barrier fusion reactions / Hong-Jun Hao and Jun-Long Tian -- Doublet structure study in A[symbol]105 mass region / C. Y. He ... [et al.] -- Rotational bands in transfermium nuclei / X. T. He -- Shape coexistence and shape evolution [symbol]Yb / H. Hua ... [et al.] -- Multistep shell model method in the complex energy plane / R. J. Liotta -- The evolution of protoneutron stars with kaon condensate / Ang Li -- High spin structures in the [symbol]Lu nucleus / Li Cong-Bo ... [et al.] -- Nuclear stopping and equation of state / QingFeng Li and Ying Yuan -- Covariant description of the low-lying states in neutron-deficient Kr isotopes / Z. X. Li ... [et al.] -- Isospin corrections for superallowed [symbol] transitions / HaoZhao Liang ... [et al.] -- The positive-parity band structures in [symbol]Ag / C. Liu ... [et al.] -- New band structures in odd-odd [symbol]I and [symbol]I / Liu GongYe ... [et al.] -- The sd-pair shell model and interacting boson model / Yan-An Luo ... [et al.] -- Cross-section distributions of fragments in the calcium isotopes projectile

  1. The Legnaro National Laboratories and the SPES facility: nuclear structure and reactions today and tomorrow

    International Nuclear Information System (INIS)

    De Angelis, Giacomo; Fiorentini, Gianni

    2016-01-01

    There is a very long tradition of studying nuclear structure and reactions at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di Fisica Nucleare (Italian Institute of Nuclear Physics). The wide expertise acquired in building and running large germanium arrays has made the laboratories one of the most advanced research centers in γ -ray spectroscopy. The ’gamma group’ has been deeply involved in all the national and international developments of the last 20 years and is currently one of the major contributors to the AGATA project, the first (together with its American counterpart GRETINA) γ -detector array based on γ -ray tracking. This line of research is expected to be strongly boosted by the coming into operation of the SPES radioactive ion beam project, currently under construction at LNL. In this report, written on the occasion of the 40th anniversary of the Nobel prize awarded to Aage Bohr, Ben R Mottelson and Leo Rainwater and particularly focused on the physics of nuclear structure, we intend to summarize the different lines of research that have guided nuclear structure and reaction research at LNL in the last decades. The results achieved have paved the way for the present SPES facility, a new laboratories infrastructure producing and accelerating radioactive ion beams of fission fragments and other isotopes. (invited comment)

  2. The Legnaro National Laboratories and the SPES facility: nuclear structure and reactions today and tomorrow

    Science.gov (United States)

    de Angelis, Giacomo; Fiorentini, Gianni

    2016-11-01

    There is a very long tradition of studying nuclear structure and reactions at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di Fisica Nucleare (Italian Institute of Nuclear Physics). The wide expertise acquired in building and running large germanium arrays has made the laboratories one of the most advanced research centers in γ-ray spectroscopy. The ’gamma group’ has been deeply involved in all the national and international developments of the last 20 years and is currently one of the major contributors to the AGATA project, the first (together with its American counterpart GRETINA) γ-detector array based on γ-ray tracking. This line of research is expected to be strongly boosted by the coming into operation of the SPES radioactive ion beam project, currently under construction at LNL. In this report, written on the occasion of the 40th anniversary of the Nobel prize awarded to Aage Bohr, Ben R Mottelson and Leo Rainwater and particularly focused on the physics of nuclear structure, we intend to summarize the different lines of research that have guided nuclear structure and reaction research at LNL in the last decades. The results achieved have paved the way for the present SPES facility, a new laboratories infrastructure producing and accelerating radioactive ion beams of fission fragments and other isotopes.

  3. Nuclear structure studies by means of magnetic moments of excited states

    International Nuclear Information System (INIS)

    Kaeubler, L.; Prade, H.; Schneider, L.; Brinckmann, H.F.; Stary, F.

    1981-09-01

    Experimental arrangements installed at the cyclotron U-120 and the tandem accelerator EGP-10 for the in-beam measurement of magnetic moments of excited nuclear states are discribed. The Perturbed-Angular-Distribution-method (PAD) has been used. A new evaluation method has been developed for the unique determination of the Larmor frequency from spin-procession spectra R(t) with less than half of an oscillation period between consecutive particle pulses. Magnetic moments in transitional nuclei or in nuclei near closed shells ( 103 Pd, 105 Ag, 117 Sb, 117 Te, 121 Te, 121 I, 143 Pm and 207 Bi) were measured. The results are discussed with the aim to get information about the nuclear structure of the corresponding isomeric states in connection with complex spectroscopic investigations. Therefore, the experimental values are compared to the results of model calculations (core-polarization, core-particle-coupling, Nilsson, particle-rotation-coupling or shell-model) or to the estimates on the basis of the additivity of effective magnetic moments. Single-particle aspects are discussed in connection with the magnetic moments of hsub(11/2)-, dsub(5/2)- and gsub(7/2)-neutron (ν) and proton (π) states in the nuclei 103 Pd, 117 Te, 121 Te and 143 Pm, respectively. The configurations of (π) 3 and (π)(ν) 2 -three-particle states in 105 Ag, 117 Sb, 121 I and 207 Bi could be determined using the additivity rule. The experimental magnetic moments of states in 143 Pm agree very well with the results of shell-model calculations, which have firstly been carried out also for negative-parity states in this mass region. Considering magnetic moments in 117 Te and 121 Te we could demonstrate the influence of different nuclear deformations on the magnetic moments in transitional nuclei. (author)

  4. Hartree-Fock description of superdeformed states

    International Nuclear Information System (INIS)

    Dobaczewski, J.; Meyer, J.

    1991-10-01

    The discovery of superdeformation has been preceded by theoretical predictions made in Nilsson-Strutinsky calculations and a description of the phenomenon still constitutes an exciting challenge to the theory of nuclear collective motion. In particular, a determination of electromagnetic transition rates requires a knowledge of microscopic collective wave functions, which can be achieved by using the Hartree-Fock (HF) theory and the generator coordinate method (GCM). In this study we present results of our calculations concerning the properties and superdeformed states in the mercury region. Using the GCM, we diagonalize the microscopic two-body hamiltonian within the basis set of constrained HF+BCS wave functions. The GCM provides values for the energy of the ground and excited states including the shape isomer which take into account the effect of correlations in the collective degree of freedom. The GCM will also allow us to discuss the qualitative modifications of the shape isomeric stability as induced by changes in pairing correlations

  5. Absolute El Transition Probabilities in the Deformed Nuclei 177Yb and Hf179

    International Nuclear Information System (INIS)

    Malmskog, Sven G.

    1964-08-01

    The absolute E1-transition probabilities have been measured for two 7/2 - (514) levels populated from the short-lived isomers 177m Yb (6.4 sec) and 179m Hf (18.6 sec), a delayed coincidence set up being used for the purpose. This gave a half life of T 1/2 = (4.48 ± 0.08)x10 -9 sec for the 104 keV level in 177 Yb and T 1/2 = (1.86 ± 0.05)x10 -9 sec for the 217 keV level in 179 Hf. The result has been compared with the calculations made by Nilsson. The effect of the pairing correlation has also been taken into account. An agreement with the experimental values to within a factor of three is obtained. An extrapolated estimate of the half life for the 408.9 keV 7/2 - (514) level in 181 W gives 3x10 -11 sec

  6. Studies of high-K isomers in hafnium nuclei

    International Nuclear Information System (INIS)

    Sletten, G.; Gjoerup, N.L.

    1991-01-01

    K-isomeric states built on high-Ω Nilsson orbitals from deformation-aligned high-j levels near the Fermi surface are found to cluster in the neutron rich Hf, W and Os nuclei. It has been shown that some of the high seniority states of this type have decay properties that indicate strong mixing of configurations and that in Osmium nuclei γ-softness cause strong deviations from the well established K-selection rule. Also in the Hafnium nuclei is the expected forbiddenness in isomeric decays an order of magnitude smaller than expected from the K-selection rule. A new 9 quasiparticle isomer has been discovered in 175 Hf at I=57/2. This isomer has the anomalous decay as the dominant mode. Other lower seniority states are also identified. At spin 35/2 and 45/2 the deformation aligned states become yrast, but the structure of the yrast line to even higher spins is not yet understood. (author)

  7. The role of spin-orbit potential in nuclear prolate-shape dominance

    Energy Technology Data Exchange (ETDEWEB)

    Takahara, Satoshi, E-mail: staka@ks.kyorin-u.ac.jp [Kyorin University, School of Medicine, Mitaka, Tokyo 181-8611 (Japan); Onishi, Naoki [University of Tokyo (Japan); University of Yamanashi (Japan); Shimizu, Yoshifumi R. [Department of Physics, Graduate School of Science, Kyushu University, Fukuoka 812-8581 (Japan); Tajima, Naoki [Department of Applied Physics, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507 (Japan)

    2011-08-26

    It is confirmed, in terms of the Woods-Saxon-Strutinsky method, that the spin-orbit potential plays a decisive role in the predominance of prolate deformation, which has been a long standing problem in nuclear physics. It is originated from the combined effects of the spin-orbit coupling and the diffused surface of the potential, in agreement with the previous work based on a more schematic Nilsson-Strutinsky method. The degree of prolate-shape dominance exhibits an oscillatory behavior with respect to the strength of spin-orbit potential and, the prolate-shape dominance is realized at the proper strength of the spin-orbit potential together with the standard surface diffuseness; this oscillatory behavior disappears in case of small diffuseness corresponding to ellipsoidal cavity. The calculated energy differences between oblate and prolate minima in this Letter are consistent with those of our extensive self-consistent calculations of the Hartree-Fock + BCS method with the Skyrme interaction.

  8. The role of spin-orbit potential in nuclear prolate-shape dominance

    International Nuclear Information System (INIS)

    Takahara, Satoshi; Onishi, Naoki; Shimizu, Yoshifumi R.; Tajima, Naoki

    2011-01-01

    It is confirmed, in terms of the Woods-Saxon-Strutinsky method, that the spin-orbit potential plays a decisive role in the predominance of prolate deformation, which has been a long standing problem in nuclear physics. It is originated from the combined effects of the spin-orbit coupling and the diffused surface of the potential, in agreement with the previous work based on a more schematic Nilsson-Strutinsky method. The degree of prolate-shape dominance exhibits an oscillatory behavior with respect to the strength of spin-orbit potential and, the prolate-shape dominance is realized at the proper strength of the spin-orbit potential together with the standard surface diffuseness; this oscillatory behavior disappears in case of small diffuseness corresponding to ellipsoidal cavity. The calculated energy differences between oblate and prolate minima in this Letter are consistent with those of our extensive self-consistent calculations of the Hartree-Fock + BCS method with the Skyrme interaction.

  9. A survey of present levels of radiocesium in Swedish pulp mill liquors and the implications for wood radiocesium transfer factors

    International Nuclear Information System (INIS)

    Ravila, A.; Holm, E.

    1998-01-01

    Assessments of the impact from radioactive fallout on the pulp industry and the accumulation processes for radionuclides in such industries, using wood and water as primary raw materials, have been conducted in previous studies. Hitherto, there is a general lack of data on present levels of radioactivity in pulp mill liquors apart from the few mills studied by [NILSSON (1992)] [RAVILA AND HOLM (1992)] [MANJON ET AL. (1996) and [KROSSHAVN ET AL. (1997)]. A survey was therefore initiated to describe and compare the present activity levels in pulp mill liquors from various mill locations in Sweden. The 137 Cs activity in pulp mill liquors were compared with the mill location and the deposition pattern of the Chernobyl fallout and nuclear weapons fallout. The large input of wood (approx. 2500 m 3 day -1 ) to an average Nordic Kraft mill and the relatively long-term retention time for radiocesium in the Kraft mill recovery cycle enables representative sampling of substances directly related to the activity concentration in wood

  10. Absolute El Transition Probabilities in the Deformed Nuclei {sup 177}Yb and {sup 1}

    Energy Technology Data Exchange (ETDEWEB)

    Malmskog, Sven G

    1964-08-15

    The absolute E1-transition probabilities have been measured for two 7/2{sup -} (514) levels populated from the short-lived isomers {sup 177m}Yb (6.4 sec) and {sup 179m}Hf (18.6 sec), a delayed coincidence set up being used for the purpose. This gave a half life of T{sub 1/2} = (4.48 {+-} 0.08)x10{sup -9} sec for the 104 keV level in {sup 177}Yb and T{sub 1/2} = (1.86 {+-} 0.05)x10{sup -9} sec for the 217 keV level in {sup 179}Hf. The result has been compared with the calculations made by Nilsson. The effect of the pairing correlation has also been taken into account. An agreement with the experimental values to within a factor of three is obtained. An extrapolated estimate of the half life for the 408.9 keV 7/2{sup -} (514) level in {sup 181}W gives 3x10{sup -11} sec.

  11. Levels in {sup 227}Ac populated in the {sup 230}Th(p,{alpha}) reaction

    Energy Technology Data Exchange (ETDEWEB)

    Burke, D.G. E-mail: dgb@physics.mcmaster.ca; Garrett, P.E.; Qu, Tao

    2003-09-08

    The {sup 230,232}Th(p,{alpha}){sup 227,229}Ac reactions were studied using 20 MeV protons and a magnetic spectrograph to analyze the reaction products. Relative populations of levels in {sup 229}Ac correlated well with previously published (t,{alpha}) results for the same final levels, showing that the similarity of the two reactions observed empirically in the deformed rare earth region extends to actinides. The most strongly populated level in {sup 227}Ac is at 639 keV, and is assigned as the 1/2{sup +}[4 0 0] bandhead. The 435 keV level, previously adopted as the 1/2{sup +}[6 6 0] bandhead, also has a significant intensity that is attributed to {delta}N=2 mixing between these two K=1/2 proton orbitals. The {delta}N=2 matrix element estimated from these data is {approx}80 keV, similar to values observed for the same two Nilsson states as neutron orbitals in the dysprosium isotopes.

  12. New species and host plants of Anastrepha (Diptera: Tephritidae) primarily from Peru and Bolivia.

    Science.gov (United States)

    Norrbom, Allen L; Rodriguez, Erick J; Steck, Gary J; Sutton, Bruce A; Nolazco, Norma

    2015-11-16

    Twenty-eight new species of Anastrepha are described and illustrated: A. acca (Bolivia, Peru), A. adami (Peru), A. amplidentata (Bolivia, Peru), A. annonae (Peru), A. breviapex (Peru), A. caballeroi (Peru), A. camba (Bolivia, Peru), A. cicra (Bolivia, Peru), A. disjuncta (Peru), A. durantae (Peru), A. echaratiensis (Peru), A. eminens (Peru), A. ericki (Peru), A. gonzalezi (Bolivia, Peru), A. guevarai (Peru), A. gusi (Peru), A. kimi (Colombia, Peru), A. korytkowskii (Bolivia, Peru), A. latilanceola (Bolivia, Peru), A. melanoptera (Peru), A. mollyae (Bolivia, Peru), A. perezi (Peru), A. psidivora (Peru), A. robynae (Peru), A. rondoniensis (Brazil, Peru), A. tunariensis (Bolivia, Peru), A. villosa (Bolivia), and A. zacharyi (Peru). The following host plant records are reported: A. amplidentata from Spondias mombin L. (Anacardiaceae); A. caballeroi from Quararibea malacocalyx A. Robyns & S. Nilsson (Malvaceae); A. annonae from Annona mucosa Jacq. and Annona sp. (Annonaceae); A. durantae from Duranta peruviana Moldenke (Verbenaceae); and A. psidivora from Psidium guajava L. (Myrtaceae).

  13. Underlying physics of identical odd- and even-mass bands in normally deformed rare-earth nuclei

    International Nuclear Information System (INIS)

    Yu Lei; Liu Shuxin; Lei Yian; Zeng Jinyan

    2001-01-01

    The microscopic mechanism of the identical odd- and even-mass number nuclear bands in normally deformed rare-earth nuclei was investigated using the particle-number conserving (PNC) method for treating nuclear pairing correlation. It was found that the odd particle of an odd-A identical band always occupied a cranked low j and high Ω Nilsson orbital (e.g. proton [404]7/2, [402]5/2. On the contrary, if the odd particle occupies an intruder high j orbital (e.g. neutron [633]7/2, proton[514]9/2), the moment of inertia of the odd-A band was much larger than that of neighboring even-even ground state band. The observed variation of moment of inertia (below band crossing) was reproduced quite well by the PNC calculation, in which no free parameter was involved. The strengths of monopole and Y 20 quadrupole interactions were determined by the experimental odd-even differences in binding energy and band head moment of inertia

  14. β- decay of 150Ce to odd-odd 150Pr

    International Nuclear Information System (INIS)

    Kojima, Yasuaki; Shibata, Michihiro; Kosuga, Kazuto; Shima, Yosuke; Taniguchi, Akihiro; Hayashi, Hiroaki

    2015-01-01

    The β - decay of 150 Ce having a half-life of 6.05(7) s produced by the thermal-neutron-induced fission of 235 U has been studied using the on-line isotope separator at the Kyoto University Research Reactor. A decay scheme containing 18 excited levels and 55 γ-rays was constructed from γ-ray singles and γ-γ coincidence measurements. Of these, 9 levels and 37 γ-rays were newly placed. The dominant β-feeding observed at the 110 keV level of 150 Pr was found to be an allowed unhindered spin-flip transition. On the basis of the systematics of the neighboring nuclides, the Gallagher-Moszkowski coupling rules, and the selection rules for the β-decay of deformed nuclei, the Nilsson configurations of the ground and 110 keV states in 150 Pr were newly proposed to be π5/2 + [413]-ν3/2 - [521] and π5/2 - [532]-ν3/2 - [532], respectively. (author)

  15. “Send pretty girls to the White House”: the role of gender in journalists – politicians’ interactions

    Directory of Open Access Journals (Sweden)

    Liudmila VORONOVA

    2014-12-01

    Full Text Available Interrelations between politics and media are often described as a power-play, a rumba or even a danse macabre, and the key question of political communication is “who leads and who follows” in the “power-play between politicians and journalists” (Ross, 2010, p. 274. As today “[m]eaning, media and politics become blurred, but arguably in highly gendered ways” (Holmes, 2007, p. 12, gender inevitably enters the discussion of the journalists – politicians’ interactions. Based on interviews with 40 Russian and Swedish political reporters working for the “quality” press, this paper discusses the role of gender as a social practice (Löfgren Nilsson, 2010 in journalists – politicians’ communication in different political and cultural contexts, which Russia and Sweden represent. The paper answers the following questions: Do journalists perceive the interrelations with politicians as gendered? Do they use gendered interrelations strategically to acquire information efficiently? How do the gendered political communication practices differ dependent on the political and cultural context?

  16. Possible Deformed States in 115In and 117ln

    International Nuclear Information System (INIS)

    Baecklin, A.; Fogelberg, B.; Malmskog, S.G.

    1967-01-01

    Levels and transitions in 115 In and 117 In have been studied from the beta decay of 2.3-day 115g Cd and 2.5-h 117g Cd. Using a Ge(Li) detector and a double focussing beta spectrometer energies, intensities, conversion coefficients and multipolarities were obtained for the following transitions (energies in keV and multipolarities are given): 115 In: 35.63 (97.0 % M1 + 3.0 % E2), 231.47 (E1), 260.80 (M1), 267, 336. 23 (M4 + 117 In: 71.0, 89.80 (E2 + 115 In and for 3 levels in 117 In. Energies, spins, parities and half lives are given for the following levels: In: 597.03, 3/2 - ; 828.39, 3/2 + , 5.4 ns; 863.95, l/2 + or 3/2 + , 1.1 ns. 117 In: 588.59, 3/2 - ; 0.20 ns; 659.56, 3/2 + , 58.7 ns; 749.37, 1/2 + or 3/2 + , 4.3 ns. Reduced transition probabilities are given for several transitions in both nuclei. The E2 transition rates between the two excited positive parity states in both nuclei were found to be about 100 s. p. u. indicating a possible deformation of these states. The energy spacing and transition rates between these states can be well accounted for within the Nilsson model assuming the states to form a K = 1/2 + rotational band. A deformation δ of about 0.20 is obtained for both nuclei

  17. Study of High-Resolution Spectroscopy of Plutonium. Part I. Contribution to the Classification of the Arc Spectrum. Part II. Determination of the Magnetic Moment of 239Pu

    International Nuclear Information System (INIS)

    Gerstenkorn, S.

    1962-01-01

    The study of the hyperfine structure and isotope shift enabled the positions of the first five levels of the multiplet 7 F 0-6 belonging to the fundamental configuration 5f 6 7s 2 to be determined. The classification of the arc spectrum begun in this way led to 25 odd levels, the number of classified lines (70) representing about 30 p. 100 of the light emitted by this hollow cathode in the visible. In addition, the isotope shifts of many lines and the data given by the King furnace show that the first levels of the configuration 5f 5 6d7s 2 are also low less than 8000 cm -1 above the fundamental level 7 F 0 . The proximity of the configuration f 6 s 2 and f 5 ds 2 shows that the bonding energies of the 5f and 6d electrons are of the same order of magnitude and this fact must be responsible for the multiple valences belonging to plutonium. From the hyperfine structure of spark lines (Pu II) the interval factor a 7 for the electron was deduced giving for the calculated nuclear moment of 239 Pu a value of +0.21 ±0.06 μ N . The position of the hyperfine components show that the nuclear moment is positive, although the theoretical value given by B. R. Mottelson and S. Nillson is negative and equal to -0.1 μ N . (author) [fr

  18. Collective properties of nucleons in the abnormal-parity states

    International Nuclear Information System (INIS)

    Bhatt, K. H.; Kahane, S.; Raman, S.

    2000-01-01

    In the first part of this work, we study the quadrupole collective properties of N a =2, 4, 6, and 8 nucleons occupying the abnormal-parity intruder single-particle states with high angular momenta j a =(9/2), (11/2), (13/2), and (15/2). This study is essential for a detailed understanding of the contribution made by these nucleons to the quadrupole collectivity of the yrast states of deformed nuclei. The properties studied include (i) the distribution of the angular momenta J contained in the intrinsic state of N a particles in the |j a k a > states, (ii) the relationship between the quadrupole moment Q 0 (j a ,N a ) of such an intrinsic state and the maximum angular momentum J max contained in it, (iii) the complete set of reduced quadrupole matrix elements (J ' ||Q||J) for transitions between all the states |J> and |J ' > projected from the intrinsic state, (iv) the B(E2:J→J-2) values, (v) the transition moments Q t (J), and (vi) the spectroscopic quadrupole moment Q(J). We compare these properties with similar properties of an intrinsic state having SU(3) symmetry which contains the same set of angular momenta as contained in the intrinsic state of a particular number of nucleons in a specific j a configuration. In the second part, we use the input from the first part to study the collective properties of the coupled system of protons and neutrons in abnormal-parity states. We show that the SU(3)-like features observed for the individual groups of abnormal-parity nucleons become stronger for the coupled system. Finally, in the third part, we consider the yrast bands of well-deformed nuclei projected from their Nilsson intrinsic states of valence nucleons in a major shell. We specify the structure of the wave function of each projected yrast state |J> in terms of the nucleons in both normal- and abnormal-parity states. These wave functions can be used to determine the individual contributions of the nucleons in normal- and abnormal-parity states to any

  19. The Prospect of using Three-Dimensional Earth Models To Improve Nuclear Explosion Monitoring and Ground Motion Hazard Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Zucca, J J; Walter, W R; Rodgers, A J; Richards, P; Pasyanos, M E; Myers, S C; Lay, T; Harris, D; Antoun, T

    2008-11-19

    finite difference methods (e.g. Pitarka, 1999; Nilsson et al., 2007). The ability to compute seismic observables using a 3D model is only half of the challenge; models must be developed that accurately represent true Earth structure. Indeed, advances in seismic imaging have followed improvements in 3D computing capability (e.g. Tromp et al., 2005; Rawlinson and Urvoy, 2006). Advances in seismic imaging methods have been fueled in part by theoretical developments and the introduction of novel approaches for combining different seismological observables, both of which can increase the sensitivity of observations to Earth structure. Examples of such developments are finite-frequency sensitivity kernels for body-wave tomography (e.g. Marquering et al., 1998; Montelli et al., 2004) and joint inversion of receiver functions and surface wave group velocities (e.g. Julia et al., 2000).

  20. Study of High-Resolution Spectroscopy of Plutonium. Part I. Contribution to the Classification of the Arc Spectrum. Part II. Determination of the Magnetic Moment of {sup 239}Pu; Etude du plutonium par spectroscopie a haute resolution: contribution a la classification du spectre d'arc et determination du moment magnetique de {sup 239}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Gerstenkorn, S

    1962-07-01

    The study of the hyperfine structure and isotope shift enabled the positions of the first five levels of the multiplet {sup 7}F{sub 0-6} belonging to the fundamental configuration 5f{sup 6}7s{sup 2} to be determined. The classification of the arc spectrum begun in this way led to 25 odd levels, the number of classified lines (70) representing about 30 p. 100 of the light emitted by this hollow cathode in the visible. In addition, the isotope shifts of many lines and the data given by the King furnace show that the first levels of the configuration 5f{sup 5}6d7s{sup 2} are also low less than 8000 cm{sup -1} above the fundamental level {sup 7}F{sub 0}. The proximity of the configuration f{sup 6}s{sup 2} and f{sup 5}ds{sup 2} shows that the bonding energies of the 5f and 6d electrons are of the same order of magnitude and this fact must be responsible for the multiple valences belonging to plutonium. From the hyperfine structure of spark lines (Pu II) the interval factor a{sub 7} for the electron was deduced giving for the calculated nuclear moment of {sup 239}Pu a value of +0.21 {+-}0.06 {mu}{sub N}. The position of the hyperfine components show that the nuclear moment is positive, although the theoretical value given by B. R. Mottelson and S. Nillson is negative and equal to -0.1 {mu}{sub N}. (author) [French] Partie 1 - L'etude des structures hyperfines et du deplacement isotopique des raies du spectre d'arc du plutonium a permis de determiner la position des cinq premiers niveaux du multiplet {sup 7}F{sub 0-6} correspondant a la configuration fondamentale 5f{sup 6}7s{sup 2}. Des lors, la classification du spectre d'arc du plutonium pouvait etre amorcee: 25 niveaux impairs ont ete mis en evidence et le nombre de raies classees (70) represente environ 30 p. 100 de l'intensite totale du spectre d'arc emis par une cathode creuse dans le visible. D'autre part, le deplacement isotopique de certaines raies, joint aux renseignements donnes par le spectre emis par le four

  1. Study of the superdeformed states of the gadolinium nuclei: neutron excitations in {sup 147}Gd nucleus; Etude des etats superdeformes de noyaux de Gadolinium: Excitations neutron dans le noyau {sup 147}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Khadiri, Najia [Institut de Recherche Subatomique, CNRS-IN2P3 - Universite Louis Pasteur, 67 - Strasbourg (France)

    1997-10-17

    This work is devoted to nuclear structure studies of superdeformed states in the second potential well. Under focus are the gadolinium isotopes and in particular the {sup 147}Gd nucleus. High spin states in {sup 147}Gd have been populating by {sup 122}Sn ({sup 30}Si,5n){sup 147}Gd fusion-evaporation reaction with a silicon beam of 158 MeV delivered by the VIVITRON accelerator of the Institut de Recherches Subatomiques. The nucleus {gamma} de-excitations have been measured using the EUROGAM II {gamma}-ray multidetector. On the basis of multiple coincidences, four new superdeformed (SD) rotational bands have been assigned to {sup 147}Gd nucleus. Nuclear structures corresponding to these bands have been investigated by shell model calculations using a harmonic oscillator potential with cranking, in the Nilsson Strutinsky formalism. Comparison of dynamical moments of inertia of band (1) and (5) in {sup 147}Gd with {sup 148}Gd(2) and {sup 146}Gd(1) SD bands has fixed the role of the [651 1/2]{alpha} = -1/2 orbital crossing frequency. Theoretical calculations reproduce quite well the {sup 148}Gd(2), {sup 127}Gd(1,5) and G{sup 146}Gd(1) dynamical moments of inertia. Using the particle hole excitation nature of {sup 149,148,147,146}Gd bands, effective spin alignment of [651 1/2]{alpha}= {+-}1/2, [770 1/2]{alpha} = -1/2 and [441 1/2]{alpha} = +1/2 orbitals have been deduced from the experiment in agreement with the theoretical values. Of particular interest, the spin alignment measured for the [441 1/2]{alpha} +1/2 orbital, with a value close to zero, is in contradiction with the value predicted by the Pseudo SU(3) model, formalism often used to explain the identical band phenomenon. (author) 68 refs., 41 figs., 17 tabs.

  2. Nuclear structure research

    International Nuclear Information System (INIS)

    Wood, J.L.

    1993-01-01

    The most significant development this year has been the successful elucidation of the low-energy systematics of the very neutron-deficient Pr, Nd, Pm, and Sm isotopes. This includes an extensive set of Nilsson bandheads in 133 Nd. Some serious errors in earlier decay scheme work were found. The results require some significant reassessments of mean-field calculations in this region. Part of our program continues to focus on shape coexistence and electric monopole (E0) transitions in nuclei. Following the discovery of coexisting ''gamma'' bands connected by E0 transitions in 184 Pt, a similar behavior in 186 Pt was established from 186 Au decay data. This includes a pure E0 transition between states with J π = 3 + , just as was seen in 184 Pt. Progress has been made in elucidating the low-energy systematics of the neutron-deficient Ir isotopes. A search for the population of the superdeformed band in 194 Pb in the decay of 194 Bi was unsuccessful. An extensive program of systematics for nuclei at and near N = Z has been initiated

  3. Fully aligned high-spin states in 86Zr

    International Nuclear Information System (INIS)

    Doring, J.; Hohns, G.D.; Sylvan, G.N.

    1995-01-01

    To study multi-quasiparticle excitations and their interplay with collective degrees of freedom at very high spins, a new in-beam investigation of the even-even 86 Zr has been performed via the 58 Ni( 32 S,4p) reaction at 135 MeV using the early implementation of GAMMASPHERE combined with the 47π charged particle detector system MICROBALL. The yrast positive- and negative-parity sequences have been extended up to 30 + and 27 - levels, respectively. Calculations within the configuration-dependent shell-correction method using a cranked Nilsson potential have shown that the highest spins are built from the six g 9 /2 neutrons and at most four protons excited from the p 1/2 , p 3/2 , f 5/2 subshells to the g 9 /2 subshell at a small deformation. The 30 + and 27 - states are the highest possible fully-aligned states based on holes in the N = 3 shell. Higher spins can be built by promotion of one neutron from the g 9 /2 to the g 7 /2 subshell but with a quite high energy cost

  4. Alpha-gamma decay studies of 253No and its daughter products 253Md, 249Fm

    International Nuclear Information System (INIS)

    Hessberger, F.P.; Antalic, S.; Kalaninova, Z.; Saro, S.; Venhart, M.; Ackermann, D.; Heinz, S.; Kindler, B.; Kojouharov, I.; Kuusiniemi, P.; Lommel, B.; Mann, R.; Sulignano, B.; Hofmann, S.; Streicher, B.; Leino, M.; Nishio, K.

    2012-01-01

    Nuclear structure and decay of the isotope 253 No and its decay products 249 Fm and 253 Md were investigated by means of α - γ spectroscopy. Besides the established strong γ transitions from the 9/2 - [734] Nilsson level in 249 Fm, populated predominantly by the α decay of 253 No, into the ground-state (gs) rotational band, a couple of weaker γ lines (58.3, 129.2, 209.3 and 669.5keV) were observed and placed into the 249 Fm level scheme. The transition from the 7/2 - level in 249 Es, populated by the α decay of 253 Md, into the 9/2 + member of the gs rotational band, so far established for other odd-mass Es isotopes, was observed clearly. GEANT4 simulations were performed to investigate the influence of energy summing between α particles and conversion electrons (CE) on the shape of the α spectra at different implantation energies, leading to evidence for a weak α decay branch of 253 No into the gs of 249 Fm or the ground-state rotational band, respectively. (orig.)

  5. Spectroscopical study of the yrast and yrare structure in far-from-stability nuclei; Etude spectroscopique de la structure yrast et yrare de noyaux loin de la stabilite

    Energy Technology Data Exchange (ETDEWEB)

    Hoellinger Fabien [Institut de Recherches Subatomiques, 23, Rue du Loess, BP 28, 67037 Strasbourg Cedex 2 (France)]|[Universite Louis Pasteur, 67 - Strasbourg (France)

    1999-01-13

    The nuclear structure study of neutron-rich nuclei was realized with the EUROGAM II array in two different experiments. The first study consisted in the analysis of the product of spontaneous fission of {sup 248}Cm. Three neutron-rich cerium isotopes {sup 147,149,151}Ce were analyzed. A level scheme for {sup 151}Ce is presented for the first time. The yrast structure of the three nuclei does not show alternative parity bands as expected in this region of octupole deformations. We studied the rotational structure of the bands and this leads to suggest Nilsson configurations to some of them. The aim of this second experiment was the study of the nuclei {sup 99}Mo, {sup 101}Tc, {sup 103}Ru. The three nuclei are situated on the neutron-rich side of the nuclear chart and are produced as fission fragments of a heavy-ion induced reaction. Some bands are extended to higher spins and some new bands are observed. The structure of the rotational bands is interpreted by means of the Hartree-Fock-Bogolyubov model. A last experiment intended to study the structure of the proton-rich nucleus {sup 223}Pa has been achieved with the JURO+RITU array located at Jyvaeskylae (Finland). In this proton-rich actinide region, the nuclei develop octupole features around Z{approx_equal}88, N{approx_equal}132. The analysis of this experiment leads to the first assignment of gamma transitions to the {sup 223}Pa. (author) 91 refs., 78 figs., 16 tabs.

  6. The Nucleus 59Cu. Complex Structure, Shape Evolution, Exotic Decay Modes

    International Nuclear Information System (INIS)

    Andreoiu, Corina

    2002-08-01

    High-spin states in the mass A∼60 region were populated using the state-of-art γ-ray spectrometers Gammasphere, Euroball, and GASP in conjunction with dedicated ancillary detectors. In particular, the 59 Cu nucleus was studied in several experiments, and a very extensive level scheme was determined. It comprises more than 320 transitions connecting about 150 excited states. Relative to mass, it is the most extensive level scheme known to date. Next to the spherical states at low excitation energy eight regular sequences of high-energy γ-ray transitions have been observed. They form rotational bands with various degree of deformation, which are interpreted in the light of the shell model and the configuration-dependent Cranked Nilsson-Strutinsky approach. One of the experiments was dedicated to the study of prompt particle decays. It revealed five prompt proton decays connecting five deformed states in three of the rotational bands in 59 Cu with three spherical states in the daughter nucleus 58 Ni. It is the first observation of the fine structure of the newly discovered prompt proton decay mode. The proton decays compete with the γ decay-out from the second minimum of the nuclear potential into the low-spin spherical states in the first minimum of the potential. The discrete γ decay-out mechanism of the yrast superdeformed band is investigated in detail. The nucleus 59 Zn, the mirror partner of 59 Cu, was identified for the first time, and the mirror symmetry of the T=1/2 A=59 pair is discussed

  7. Collective motion and alignment of particles at high angular momentum. Study of transition nuclei 54 ≤Z ≤60

    International Nuclear Information System (INIS)

    El-Samman, H.

    1986-03-01

    A Multidetector system such as multiplicity filter, set-up for energy γ energy γ correlation measurements and 12 and 14 element modular sum-spectrometers has been built with hexagonal cross-section NaI (T1) detectors. This system is used in studies of continuum γ-ray spectra at high angular momentum to determine the collective J band (2) and effective J eff (2) dynamic moments of inertia in 54≤Z≤60 transitional nuclei. Comparisons between our measurements and calculations in a cranking Nilsson-Strutinsky model show that 128,130 Ba have a pure collective behaviour with pure prolate (γ =0 deg) deformation at high spin while 118,122 Xe are triaxial (γ = 33 deg) with moderate deformation (ε = 0.25). We demonstrate the existence of a secondary minimum at larger deformation (ε = 0.35) in the potential energy surfaces of 128,130 Ba. This minimum is associated with the alignment of h 9/2 and i 13/2 neutrons and produces a shape change in the bariums. The influence of the odd proton in the A = 120 region is also demonstrated by the shape change from triaxial to prolate we observed in 123 Cs at high frequency. Informations on deformation and particle alignement are obtained from measurements of J eff (2) in Xe, Ba, Ce and Nd isotopes. A direct comparison of J band (2) and J eff (2) shows that collective motion and particle alignment participate for about 50 % each in the total increase of angular momentum [fr

  8. Systematics of B(E2;01+→21+) values for even-even nuclei

    International Nuclear Information System (INIS)

    Raman, S.; Nestor, C.W. Jr.; Bhatt, K.H.

    1988-01-01

    We have completed a compilation of experimental results for the electric quadrupole transition probability B(E2)up-arrow between the 0 + ground state and the first 2 + state in even-even nuclei. The adopted B(E2)up-arrow values have been employed to test the various systematic, empirical, and theoretical relationships proposed by several authors (Grodzins, Bohr and Mottelson, Wang et al., Ross and Bhaduri, Patnaik et al., Hamamoto, Casten, Moeller and Nix, and Kumar) on a global, local, or regional basis. These systematics offer methods for making reasonable predictions of unmeasured B(E2) values. For nuclei away from closed shells, the SU(3) limit of the intermediate boson approximation implies that the B(E2)up-arrow values are proportional to (e/sub p/N/sub p/+e/sub n/N/sub n/) 2 , where e/sub p /(e/sub n/) is the proton (neutron) effective charge and N/sub p/ (N/sub n/) refers to the number of valence protons (neutrons). This proportionality is consistent with the observed behavior of B(E2)up-arrow vs N/sub p/N/sub n/. For deformed nuclei and the actinides, the B(E2)up-arrow values calculated in a schematic single-particle ''SU(3)'' simulation or large single-j simulation of major shells successfully reproduce not only the empirical variation of the B(E2)up-arrow values but also the observed saturation of these values when plotted against N/sub p/N/sub n/. .AE

  9. Order and chaos in nuclear and metal cluster deformation

    International Nuclear Information System (INIS)

    Radu, S.

    1995-08-01

    The vast amount of nuclear and metal cluster data indicates that shell structure and deformation are two simultaneous properties. A conflicting situation is therefore encountered as the shell structure, a firm expression of order, is apparently not compatible with the non-integrable nature of the models incorporating deformation. The main issue covered in this thesis is the intricate connection between deformation and chaotic behaviour in deformation models pertinent to nuclear structure and metal cluster physics. It is shown that, at least in some cases, it is possible to reconcile the occurrence of shell structure with non-integrability. The coupling of an axially deformed harmonic oscillator to an axially symmetric octupole term renders the problem non-integrable. The chaotic character of the motion is strongly dependent on the type of deformation, in that a prolate shape shows virtually no chaos, while in an oblate case the motion exhibits fully developed chaos when the octupole term is switched on. Whereas the problem is non-integrable, the quantum mechanical spectrum nevertheless shows some shell structure in the prolate case for particular, yet fairly large octupole strengths; for spherical or oblate deformation the shell structure disappears. This result is explained in terms of classical periodic orbits which are found by employing the 'removal of resonances method'. Particular emphasis is put on the effect of the hexadecapole deformation which is important in fission processes. The combined effect of octupole and hexadecapole deformation leads to important conclusions for the experimental work as a high degree of ambiguity is signaled for the interpretation of data. The ambiguity results from the discovery of a mutual cancellation of the octupole and hexadecapole deformation in prolate superdeformed systems. The phenomenological Nilsson model is treated in a similar way. It is argued that while in nuclei it produces good results for the low-lying levels

  10. Representaciones de lo identitario e ideología estética en el cine de Leonardo Favio, Fernando Solanas, Leopoldo Torre Nilsson y Alejandro Agresti

    OpenAIRE

    Tabarrozzi, Marcos Leonardo

    2007-01-01

    Pareciera que las razones que Gilles Deleuze despliega en su Cinemá (1985) para referirse a la “explosión” del cine político moderno en el Tercer Mundo (el pueblo está ausente o sólo existe en estado de minoría, no hay límites discernibles entre lo público y lo privado, es imposible comunicar sino es con la lengua del amo colonial) , configuraran todavía un marco sugestivo para pensar el panorama total de los cines de la periferia global. En la complejidad de la escena contemporánea, bajo el ...

  11. Population of yrast states in 191Os using deep-inelastic reactions

    Science.gov (United States)

    Jones, G. A.; Podolyák, Zs; Walker, P. M.; Regan, P. H.; de Angelis, G.; Axiotis, M.; Bazzacco, D.; Bizzeti, P. G.; Brandolini, F.; Broda, R.; Bucurescu, D.; Farnea, E.; Gelletly, W.; Gadea, A.; Ionescu-Bujor, M.; Iordachescu, A.; Kröll, Th; Langdown, S. D.; Lunardi, S.; Marginean, N.; Martinez, T.; Medina, N. H.; Quintana, B.; Rubio, B.; Ur, C. A.; Valiente-Dobón, J. J.; Williams, S. J.; Zhang, Y. H.

    2005-10-01

    Several nuclei in the A ~ 190 region have been studied following deep-inelastic reactions using a 460 MeV 82Se projectile impinging upon a thick 192Os target. The GASP array (at the Legnaro National Laboratory in Italy) was used to measure the resulting γ-decays. The previously reported near-yrast structure of 191Os is extended to a t\\frac{1{2}} = 61 ns isomer, at an energy of 2640 keV. Branching ratios for ΔI = 1 and ΔI = 2 transitions in the Kπ =\\frac{11}{2}+ band have been measured, giving |(gK - gR)/Q0| = 0.022(3) and 0.024(7) for transitions from the \\frac{17}{2}+ and \\big(\\frac{19}{2}^+\\big) states respectively. These are consistent with the theoretical calculation for the proposed ν11/2+[615] configuration of the band. Nilsson plus BCS calculations reveal that the isomer is likely to have a {ν11/2+[615] π11/2-[505] π9/2-[514]} configuration with Jπ =Kπ =\\frac{31}{2}+ . This yields an implied reduced hindrance of fν= 1.9, in accordance with empirical systematics of K isomers in the A ~ 180-190 region.

  12. Multi-quasi-particle states in 173Hf

    International Nuclear Information System (INIS)

    Fabricius, B.; Dracoulis, G.D.; Kibedi, T.; Stuchbery, A.E.; Baxter, A.M.

    1991-01-01

    Rotational bands built on 1, 3 and 5 quasi-particle (qp) states in 173 Hf have been populated to medium and high spins through the 160 Gd( 18 O, 5n) reaction. The 1qp bands, previously identified as the 1/2 - [521], 5/2 - [512] and 7/2 + [633] (mixed i 13/2 ) Nilsson configurations, have been extended past the first back-bend and show different alignment properties, possibly originating from deformation differences. The multi-particle states were identified from excitation energies, the properties of their associated band structures and decay patterns. The 3qp states are the previously known K π =19/2 + and 23/2 - isomeric states originating from the 7/2 + [633] quasi-neutron coupled to the 6 + and 8 - , 2-quasi-proton excitations and a K π =(13/2 + ) state possibly containing the three lowest quasi-neutrons. A 5qp state with K π =(29/2 - ) was identified as the same three lowest lying quasi-neutrons coupled to the 8 - , 2-quasi-proton excitation. The low excitation energies of these two related 3- and 5-quasi-particle states implies a reduced neutron pairing gap, which can be attributed to the effect of blocking. (orig.)

  13. The phenomenon of nucleon emission at high angular momentum states of fused compound systems

    CERN Document Server

    Rajasekaran, T R; Santhosh-Kumar, S

    2003-01-01

    Nucleon emission from high spin fused compound systems is analyzed in the framework of the statistical theory of hot rotating (STHR) nuclei. This is an elaborate version of our earlier work and we present our results for sup 1 sup 5 sup 6 Er, sup 1 sup 6 sup 6 Er, sup 1 sup 6 sup 8 Yb and sup 1 sup 8 sup 8 Hg. We predict an increase in neutron emission for sup 1 sup 6 sup 6 Er due to the abrupt decrease in neutron separation energy around I approx 55h. Since the drop in the separation energy is closely associated with the structural changes in the rotating nuclei, relative increase in neutron emission probability around certain values of angular momentum may be construed as evidence for the shape transition. A similar effect is predicted for sup 1 sup 6 sup 8 Yb around I approx 55h. We also extend the microscopic cranked Nilsson method (CNM) to hot nuclear systems and compare the results with that of the STHR method. The two methods yield different results for triaxially deformed nuclei although for biaxial d...

  14. Challenges for Greenland-wide mass balance from Cryosat-2 radar-altimetry

    DEFF Research Database (Denmark)

    Simonsen, Sebastian Bjerregaard; Forsberg, René; Sørensen, Louise Sandberg

    As the Greenland ice sheet warms, a change in the structure of the upper snow/firn occurs. This change further induces changes in the reflective properties of the firn seen from satellite radar altimetry. If not identified as changes in the reflective properties of the firn, these may be interpre......As the Greenland ice sheet warms, a change in the structure of the upper snow/firn occurs. This change further induces changes in the reflective properties of the firn seen from satellite radar altimetry. If not identified as changes in the reflective properties of the firn, these may...... be interpreted as actual surface elevation changes seen from the satellite radar altimetry (Nilsson et al., 2015).Here, we investigate how to correct the elevation change observed from the ESA Cryosat-2 radar altimetry mission to derive elevation change of the air/snow interface of the Greenland ice sheet....... The elevation change of this “real” physical surface is crucial, if the goal is to derive Greenland mass balance as done for LiDAR missions.The investigations look into waveform parameters to correct for the observed bias between Radar and LiDAR observations when using Croysat-2 level-2 data. Based...

  15. Super and hyper-deformed states, and reactions to populate them

    International Nuclear Information System (INIS)

    Cseh, J.; Darai, J.; Algora, A.; Antonenko, N.; Adamian, G.

    2011-01-01

    We study the possible binary cluster configurations of the superdeformed and hyper-deformed states of some N=Z nuclei. We have determined the shape isomers from the quasi-dynamical U(3) symmetry obtained from Nilsson calculations. In searching for the possible binary clusterization of the shape isomers we have taken into account both natural laws which govern the building up of a nucleus from smaller constituents. The exclusion principle was taken into account by applying a selection rule (in combination with Harvey's prescription), based on the microscopic configuration associated to the quasi-dynamical U(3) symmetry. In this way the Pauli-principle is incorporated only in an approximate way. The clusters were considered to have a deformation, like the corresponding free nuclei (spherical, prolate, oblate or triaxial), and no constraints were applied for their relative orientation. The methods we applied here seem to be applicable in heavier nuclei, too. Symmetry considerations can be helpful in studying both the shape isomers of nuclei, and their clusterization. These investigations contribute to the structural understanding of the shape isomers, and indicate some reaction channels to populate them

  16. Dependência tabágica, assertividade e alexitimia em doentes cardíacos

    Directory of Open Access Journals (Sweden)

    Vânia Rocha

    2010-08-01

    Full Text Available O tabagismo é uma das principais causas evitáveis de morte, aumentando acentuadamente o risco de infarto do miocárdio. Este último está associado a certas variáveis psicossociais relacionadas com o tabagismo, nomeadamente a alexitimia e a falta de assertividade. O objetivo do presente artigo foi caracterizar os dois tipos de dependência tabágica (fisiológica e comportamental, a assertividade e a alexitimia, e avaliar a relação das variáveis entre si, em 30 doentes homens internados com infarto. Foram aplicados o Teste de Fagerström, o Questionário de Glover-Nilsson, a Escala de "Rathus" e a TAS-20. Os resultados indicam que a alexitimia encontra-se relacionada com a dependência comportamental e com a assertividade, sugerindo que os sujeitos menos assertivos e com dificuldade em gerir afetos negativos e situações de estresse, podem recorrer ao tabagismo como mecanismo de enfrentamento. Nas intervenções voltadas à interrupção do hábito de fumar em doentes infartados deve-se enfatizar as competências sociais e de regulação emocional.

  17. The oxygen sensitivity of a multipoint antimony electrode for tissue pH measurements. A study of the sensitivity for in vivo PO2 variations below 6 kPa.

    Science.gov (United States)

    Sjöberg, F; Edwall, G; Lund, N

    1987-02-01

    Monocrystalline micro antimony electrodes in a multipoint arrangement as described by Lund et al. were placed on the skeletal muscle surface of the rabbit. Tissue oxygen levels were measured simultaneously with the MDO (Mehrdraht Dortmund Oberfläche) oxygen electrode. The sensitivity for variations in tissue PO2 (PO2(t)) was evaluated for the antimony metal-metal oxide sensor. The sensitivity (delta E/delta log10 PO2)+/- SE was found to be 21.8 +/- 1.2 mV in the interval between 0.1 kPa and 1 kPa and 53 +/- 5 mV in the interval between 1 kPa and 6 kPa. These results are not consistent with the oxygen sensitivity of monocrystalline antimony described in vitro, but are in agreement with the findings of Nilsson & Edwall. A plausible explanation for the S-shaped oxygen sensitivity curve of antimony at oxygen levels below 10 kPa could be an interaction, at the electrode surface, between the dissolved oxygen and the oxygen bound to haemoglobin. If this is the case, the use of an antimony electrode would make possible the determination of the dissociation of oxyhaemoglobin in tissues.

  18. Proceedings of the seminar on Leak-Before-Break: Progress in regulatory policies and supporting research

    International Nuclear Information System (INIS)

    Kashima, K.; Wilkowski, G.M.

    1988-03-01

    The third in a series of international Leak-Before-Break (LBB) Seminars supported in part by the US Nuclear Regulatory Commission was held at TEPCO Hall in the Tokyo Electric Power Company's (TEPCO) Electric Power Museum on May 14 and 15, 1987. The seminar updated the international policies and supporting research on LBB. Attendees included representatives from regulatory agencies, electric utility representatives, fabricators of nuclear power plants, research organizations, and university professors. Regulatory policy was the subject of presentations by Mr. G. Arlotto (US NRC, USA), Dr. H. Schultz (GRS, W. Germany), Dr. P. Milella (ENEA-DISP, Italy), Dr. C. Faidy, P. Jamet, and S. Bhandari (EDF/Septen, CEA/CEN, and Framatome, France), and Mr. T. Fukuzawa (MITI, Japan). Dr. F. Nilsson presented revised nondestructive inspection requirements relative to LBB in Sweden. In addition, several papers on the supporting research programs discussed regulatory policy. Questions following the presentations of the papers focused on the impact of various LBB policies or the impact of research findings. Supporting research programs were reviewed on the first and second day by several participants from the US, Japan, Germany, Canada, Italy, Sweden, England, and France

  19. Multi-quasi-particles states in 173Hf

    International Nuclear Information System (INIS)

    Fabricius, B.; Dracoulis, G.D.; Kibedi, T.; Stuchbery, A.E.; Baxter, A.M.

    1990-10-01

    Rotational bands built on 1, 3 and 5 quasi-particle (qp) states in 173 Hf have been populated to medium and high spins through the 160 Gd ( 18 O,5n) reaction. The 1qp bands, previously identified as the 1/2 - [521], 5/2 - [512] and 7/2 + [633] (mixed i 1 3 /2 ) Nilsson configurations, have been extended past the first back-bend and show different alignment properties, possibly originating from deformation differences. The multi-particle states were identified from excitation energies, the properties of their associated band structures and decay patterns. The 3 qp states are the previously known K π 19/2 + and 23/2 - isomeric states originating from the 7/2 + [633] quasi-neutron coupled to the 6 + and 8 - , 2-quasi-proton excitations and a K π = (13/2 + ) state possibly containing the three lowest quasi-neutrons. A 5 qp state with K π = (29/2 - ) was identified as the same three lowest lying quasi-neutrons coupled to the 8 - , 2-quasi-proton excitation. The low excitation energies of these two related 3- and 5-quasi-particle states implies a reduced neutron pairing gap, which can be attributed to the effect of blocking. 28 refs., 2 tabs., 9 figs

  20. Model-model Perencanaan Strategik

    OpenAIRE

    Amirin, Tatang M

    2005-01-01

    The process of strategic planning, used to be called as long-term planning, consists of several components, including strategic analysis, setting strategic direction (covering of mission, vision, and values), and action planning. Many writers develop models representing the steps of the strategic planning process, i.e. basic planning model, problem-based planning model, scenario model, and organic or self-organizing model.

  1. Model-to-model interface for multiscale materials modeling

    Energy Technology Data Exchange (ETDEWEB)

    Antonelli, Perry Edward [Iowa State Univ., Ames, IA (United States)

    2017-12-17

    A low-level model-to-model interface is presented that will enable independent models to be linked into an integrated system of models. The interface is based on a standard set of functions that contain appropriate export and import schemas that enable models to be linked with no changes to the models themselves. These ideas are presented in the context of a specific multiscale material problem that couples atomistic-based molecular dynamics calculations to continuum calculations of fluid ow. These simulations will be used to examine the influence of interactions of the fluid with an adjacent solid on the fluid ow. The interface will also be examined by adding it to an already existing modeling code, Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) and comparing it with our own molecular dynamics code.

  2. Critical temperature for shape transition in hot nuclei within covariant density functional theory

    Science.gov (United States)

    Zhang, W.; Niu, Y. F.

    2018-05-01

    Prompted by the simple proportional relation between critical temperature for pairing transition and pairing gap at zero temperature, we investigate the relation between critical temperature for shape transition and ground-state deformation by taking even-even Cm-304286 isotopes as examples. The finite-temperature axially deformed covariant density functional theory with BCS pairing correlation is used. Since the Cm isotopes are the newly proposed nuclei with octupole correlations, we studied in detail the free energy surface, the Nilsson single-particle (s.p.) levels, and the components of s.p. levels near the Fermi level in 292Cm. Through this study, the formation of octupole equilibrium is understood by the contribution coming from the octupole driving pairs with Ω [N ,nz,ml] and Ω [N +1 ,nz±3 ,ml] for single-particle levels near the Fermi surfaces as it provides a good manifestation of the octupole correlation. Furthermore, the systematics of deformations, pairing gaps, and the specific heat as functions of temperature for even-even Cm-304286 isotopes are discussed. Similar to the relation between the critical pairing transition temperature and the pairing gap at zero temperature Tc=0.6 Δ (0 ) , a proportional relation between the critical shape transition temperature and the deformation at zero temperature Tc=6.6 β (0 ) is found for both octupole shape transition and quadrupole shape transition for the isotopes considered.

  3. Bull trout in the Boundary System: managing connectivity and the feasibility of a reintroduction in the lower Pend Oreille River, northeastern Washington

    Science.gov (United States)

    Dunham, Jason B.; Taylor, Eric B.; Allendorf, Fred W.

    2014-01-01

    Many of the World’s rivers are influenced by large dams (>15 m high) most of which have fragmented formerly continuous habitats, and significantly altered fish passage, natural flow, temperature, and sediment fluxes (Nilsson and others, 2005; Arthington, 2012; Liermann and others, 2012). In the Pacific Northwest, dams on major rivers have been a major focus for fishery managers, primarily in regard to passage of anadromous salmonids (principally Pacific salmon and steelhead trout [Oncorhynchus mykiss], for example, Ferguson and others, 2011), but more recently other species, such as Pacific lamprey (Entosphenus tridentatus) and resident (non-anadromous) salmonids, are receiving more attention (Neraas and Spruell, 2001; Moser and others, 2002; Muhlfeld and others, 2012). In the case of resident salmonids, fish can adopt a wide range of migratory behaviors that often bring them into mainstem rivers where they can come into direct contact with large dams. When this occurs, some of the most important direct effects of dams on salmonids include barriers to upstream and downstream movement and mortality associated with entrainment within the dam or spill over dams. Biologically, these direct impacts can lead to (1) disruption of natural historical (pre-dam) genetic and demographic connectivity among local populations, (2) loss of access to historically used migratory destinations, (3) loss of individuals to the population through mortality associated with entrainment.

  4. Models and role models.

    Science.gov (United States)

    ten Cate, Jacob M

    2015-01-01

    Developing experimental models to understand dental caries has been the theme in our research group. Our first, the pH-cycling model, was developed to investigate the chemical reactions in enamel or dentine, which lead to dental caries. It aimed to leverage our understanding of the fluoride mode of action and was also utilized for the formulation of oral care products. In addition, we made use of intra-oral (in situ) models to study other features of the oral environment that drive the de/remineralization balance in individual patients. This model addressed basic questions, such as how enamel and dentine are affected by challenges in the oral cavity, as well as practical issues related to fluoride toothpaste efficacy. The observation that perhaps fluoride is not sufficiently potent to reduce dental caries in the present-day society triggered us to expand our knowledge in the bacterial aetiology of dental caries. For this we developed the Amsterdam Active Attachment biofilm model. Different from studies on planktonic ('single') bacteria, this biofilm model captures bacteria in a habitat similar to dental plaque. With data from the combination of these models, it should be possible to study separate processes which together may lead to dental caries. Also products and novel agents could be evaluated that interfere with either of the processes. Having these separate models in place, a suggestion is made to design computer models to encompass the available information. Models but also role models are of the utmost importance in bringing and guiding research and researchers. 2015 S. Karger AG, Basel

  5. Hydrological models are mediating models

    Science.gov (United States)

    Babel, L. V.; Karssenberg, D.

    2013-08-01

    Despite the increasing role of models in hydrological research and decision-making processes, only few accounts of the nature and function of models exist in hydrology. Earlier considerations have traditionally been conducted while making a clear distinction between physically-based and conceptual models. A new philosophical account, primarily based on the fields of physics and economics, transcends classes of models and scientific disciplines by considering models as "mediators" between theory and observations. The core of this approach lies in identifying models as (1) being only partially dependent on theory and observations, (2) integrating non-deductive elements in their construction, and (3) carrying the role of instruments of scientific enquiry about both theory and the world. The applicability of this approach to hydrology is evaluated in the present article. Three widely used hydrological models, each showing a different degree of apparent physicality, are confronted to the main characteristics of the "mediating models" concept. We argue that irrespective of their kind, hydrological models depend on both theory and observations, rather than merely on one of these two domains. Their construction is additionally involving a large number of miscellaneous, external ingredients, such as past experiences, model objectives, knowledge and preferences of the modeller, as well as hardware and software resources. We show that hydrological models convey the role of instruments in scientific practice by mediating between theory and the world. It results from these considerations that the traditional distinction between physically-based and conceptual models is necessarily too simplistic and refers at best to the stage at which theory and observations are steering model construction. The large variety of ingredients involved in model construction would deserve closer attention, for being rarely explicitly presented in peer-reviewed literature. We believe that devoting

  6. Modeling Documents with Event Model

    Directory of Open Access Journals (Sweden)

    Longhui Wang

    2015-08-01

    Full Text Available Currently deep learning has made great breakthroughs in visual and speech processing, mainly because it draws lessons from the hierarchical mode that brain deals with images and speech. In the field of NLP, a topic model is one of the important ways for modeling documents. Topic models are built on a generative model that clearly does not match the way humans write. In this paper, we propose Event Model, which is unsupervised and based on the language processing mechanism of neurolinguistics, to model documents. In Event Model, documents are descriptions of concrete or abstract events seen, heard, or sensed by people and words are objects in the events. Event Model has two stages: word learning and dimensionality reduction. Word learning is to learn semantics of words based on deep learning. Dimensionality reduction is the process that representing a document as a low dimensional vector by a linear mode that is completely different from topic models. Event Model achieves state-of-the-art results on document retrieval tasks.

  7. Semiparametric modeling: Correcting low-dimensional model error in parametric models

    International Nuclear Information System (INIS)

    Berry, Tyrus; Harlim, John

    2016-01-01

    In this paper, a semiparametric modeling approach is introduced as a paradigm for addressing model error arising from unresolved physical phenomena. Our approach compensates for model error by learning an auxiliary dynamical model for the unknown parameters. Practically, the proposed approach consists of the following steps. Given a physics-based model and a noisy data set of historical observations, a Bayesian filtering algorithm is used to extract a time-series of the parameter values. Subsequently, the diffusion forecast algorithm is applied to the retrieved time-series in order to construct the auxiliary model for the time evolving parameters. The semiparametric forecasting algorithm consists of integrating the existing physics-based model with an ensemble of parameters sampled from the probability density function of the diffusion forecast. To specify initial conditions for the diffusion forecast, a Bayesian semiparametric filtering method that extends the Kalman-based filtering framework is introduced. In difficult test examples, which introduce chaotically and stochastically evolving hidden parameters into the Lorenz-96 model, we show that our approach can effectively compensate for model error, with forecasting skill comparable to that of the perfect model.

  8. g-factor of the 7/2+ isomeric bandhead in 175 W

    International Nuclear Information System (INIS)

    Ionescu-Bujor, M.; Iordachescu, A.; Marginean, N.; Brandolini, F.; Pavan, P.; Lenzi, S.M.; De Poli, M.; Gadea, A.; Martinez, T.; Medina, N.H.; Ribas, R.V.; Podolyak, Zs.

    2000-01-01

    Considerable effort is presently devoted to the investigation of the high-K isomers of multi-quasiparticle intrinsic structure systematically found in the deformed nuclei with Z=72-76 of the A ≅ 180 mass region. The configuration assignments for these isomers are based on measured static moments, as well as, on experimental branching ratios in the associated bands, from which (g K - g R )/Q 0 are derived. In the multi-quasiparticle state g-factor calculations, values taken from neighbouring odd-mass nuclei are generally used for the proton and neutron deformed single-particle g-factors. A good knowledge of these quantities is required for reliable high-K state g-factor evaluations. In the present work we report on the g-factor measurement for the low-lying J π = 7/2 + isomer bandhead in 175 W described by the neutron 7/2 + [633] Nilsson orbital. The isomeric state was populated in the 164 Dy( 16 O,5n) 175 W reaction using the 83 MeV pulsed 16 O beam (pulse width 1.5 ns, repetition period 800 ns) delivered by the LNL XTU-Tandem. The target consisted of 0.5 mg/cm 2 metallic 164 Dy on thick Pb backing which stopped the recoiling 175 W nuclei and the 16 O beam. The target was placed in an external magnetic field of 27.2(6) kG whose direction was periodically reversed. The 7/2 + isomeric state with T 1/2 = 216(6) ns and E x =234.9 keV de-excites by a dipole transition of 130.9 keV to the 5/2 - level. The angular distribution of the 130.9 keV gamma-ray has been observed time-differentially by using two planar Ge detectors placed at ± 135 angle with respect to the beam direction. The background corrected time spectra I(t,θ) obtained for the magnetic field direction up and down were used to form the experimental modulation ratio R exp (t)=[I↑(t,θ) - I ↓ (t,θ)]/[I↑(t,θ) + I ↓ (t,θ)]. The modulation pattern revealed Larmor oscillations with an amplitude strongly attenuated in time. The observed damping of the anisotropy has been attributed to quadrupole

  9. Vector models and generalized SYK models

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Cheng [Department of Physics, Brown University,Providence RI 02912 (United States)

    2017-05-23

    We consider the relation between SYK-like models and vector models by studying a toy model where a tensor field is coupled with a vector field. By integrating out the tensor field, the toy model reduces to the Gross-Neveu model in 1 dimension. On the other hand, a certain perturbation can be turned on and the toy model flows to an SYK-like model at low energy. A chaotic-nonchaotic phase transition occurs as the sign of the perturbation is altered. We further study similar models that possess chaos and enhanced reparameterization symmetries.

  10. [Bone remodeling and modeling/mini-modeling.

    Science.gov (United States)

    Hasegawa, Tomoka; Amizuka, Norio

    Modeling, adapting structures to loading by changing bone size and shapes, often takes place in bone of the fetal and developmental stages, while bone remodeling-replacement of old bone into new bone-is predominant in the adult stage. Modeling can be divided into macro-modeling(macroscopic modeling)and mini-modeling(microscopic modeling). In the cellular process of mini-modeling, unlike bone remodeling, bone lining cells, i.e., resting flattened osteoblasts covering bone surfaces will become active form of osteoblasts, and then, deposit new bone onto the old bone without mediating osteoclastic bone resorption. Among the drugs for osteoporotic treatment, eldecalcitol(a vitamin D3 analog)and teriparatide(human PTH[1-34])could show mini-modeling based bone formation. Histologically, mature, active form of osteoblasts are localized on the new bone induced by mini-modeling, however, only a few cell layer of preosteoblasts are formed over the newly-formed bone, and accordingly, few osteoclasts are present in the region of mini-modeling. In this review, histological characteristics of bone remodeling and modeling including mini-modeling will be introduced.

  11. Possible Deformed States in {sup 115}In and {sup 117}ln

    Energy Technology Data Exchange (ETDEWEB)

    Baecklin, A; Fogelberg, B [Inst. of Physics, Univ. of Uppsala (Sweden); Swedish Research Councils' Laboratory, Studsvik, Nykoeping (Sweden); Malmskog, S G [AB Atomenergi, Nykoeping (Sweden)

    1967-01-15

    Levels and transitions in {sup 115}In and {sup 117}In have been studied from the beta decay of 2.3-day {sup 115g}Cd and 2.5-h {sup 117g}Cd. Using a Ge(Li) detector and a double focussing beta spectrometer energies, intensities, conversion coefficients and multipolarities were obtained for the following transitions (energies in keV and multipolarities are given): {sup 115}In: 35.63 (97.0 % M1 + 3.0 % E2), 231.47 (E1), 260.80 (M1), 267, 336. 23 (M4 + < 5 % E5), 492. 4 (96 % El +4 % M2), 527.70 (E1). {sup 117}In: 71.0, 89.80 (E2 + < 20 % M1), 273.32 (M1, E2), 315.27 (M4 + < 7 % E2), 344.29 (E1), 434.12 (E1). Using the delayed coincidence technique, half lives were measured for 2 levels in {sup 115}In and for 3 levels in {sup 117}In. Energies, spins, parities and half lives are given for the following levels: In: 597.03, 3/2{sup -}; 828.39, 3/2{sup +}, 5.4 ns; 863.95, l/2{sup +} or 3/2{sup +}, 1.1 ns. {sup 117}In: 588.59, 3/2{sup -}; 0.20 ns; 659.56, 3/2{sup +}, 58.7 ns; 749.37, 1/2{sup +} or 3/2{sup +}, 4.3 ns. Reduced transition probabilities are given for several transitions in both nuclei. The E2 transition rates between the two excited positive parity states in both nuclei were found to be about 100 s. p. u. indicating a possible deformation of these states. The energy spacing and transition rates between these states can be well accounted for within the Nilsson model assuming the states to form a K = 1/2{sup +} rotational band. A deformation {delta} of about 0.20 is obtained for both nuclei.

  12. ROCK PROPERTIES MODEL ANALYSIS MODEL REPORT

    International Nuclear Information System (INIS)

    Clinton Lum

    2002-01-01

    The purpose of this Analysis and Model Report (AMR) is to document Rock Properties Model (RPM) 3.1 with regard to input data, model methods, assumptions, uncertainties and limitations of model results, and qualification status of the model. The report also documents the differences between the current and previous versions and validation of the model. The rock properties models are intended principally for use as input to numerical physical-process modeling, such as of ground-water flow and/or radionuclide transport. The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. This work was conducted in accordance with the following planning documents: WA-0344, ''3-D Rock Properties Modeling for FY 1998'' (SNL 1997, WA-0358), ''3-D Rock Properties Modeling for FY 1999'' (SNL 1999), and the technical development plan, Rock Properties Model Version 3.1, (CRWMS MandO 1999c). The Interim Change Notice (ICNs), ICN 02 and ICN 03, of this AMR were prepared as part of activities being conducted under the Technical Work Plan, TWP-NBS-GS-000003, ''Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01'' (CRWMS MandO 2000b). The purpose of ICN 03 is to record changes in data input status due to data qualification and verification activities. These work plans describe the scope, objectives, tasks, methodology, and implementing procedures for model construction. The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The work scope for this activity consists of the following: (1) Conversion of the input data (laboratory measured porosity data, x-ray diffraction mineralogy, petrophysical calculations of bound water, and petrophysical calculations of porosity) for each borehole into stratigraphic coordinates; (2) Re-sampling and merging of data sets; (3) Development of geostatistical simulations of porosity; (4

  13. Automated protein structure modeling with SWISS-MODEL Workspace and the Protein Model Portal.

    Science.gov (United States)

    Bordoli, Lorenza; Schwede, Torsten

    2012-01-01

    Comparative protein structure modeling is a computational approach to build three-dimensional structural models for proteins using experimental structures of related protein family members as templates. Regular blind assessments of modeling accuracy have demonstrated that comparative protein structure modeling is currently the most reliable technique to model protein structures. Homology models are often sufficiently accurate to substitute for experimental structures in a wide variety of applications. Since the usefulness of a model for specific application is determined by its accuracy, model quality estimation is an essential component of protein structure prediction. Comparative protein modeling has become a routine approach in many areas of life science research since fully automated modeling systems allow also nonexperts to build reliable models. In this chapter, we describe practical approaches for automated protein structure modeling with SWISS-MODEL Workspace and the Protein Model Portal.

  14. Geologic Framework Model Analysis Model Report

    Energy Technology Data Exchange (ETDEWEB)

    R. Clayton

    2000-12-19

    The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M&O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and the

  15. Geologic Framework Model Analysis Model Report

    International Nuclear Information System (INIS)

    Clayton, R.

    2000-01-01

    The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M and O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and

  16. Model(ing) Law

    DEFF Research Database (Denmark)

    Carlson, Kerstin

    The International Criminal Tribunal for the former Yugoslavia (ICTY) was the first and most celebrated of a wave of international criminal tribunals (ICTs) built in the 1990s designed to advance liberalism through international criminal law. Model(ing) Justice examines the case law of the ICTY...

  17. Comparisons of Multilevel Modeling and Structural Equation Modeling Approaches to Actor-Partner Interdependence Model.

    Science.gov (United States)

    Hong, Sehee; Kim, Soyoung

    2018-01-01

    There are basically two modeling approaches applicable to analyzing an actor-partner interdependence model: the multilevel modeling (hierarchical linear model) and the structural equation modeling. This article explains how to use these two models in analyzing an actor-partner interdependence model and how these two approaches work differently. As an empirical example, marital conflict data were used to analyze an actor-partner interdependence model. The multilevel modeling and the structural equation modeling produced virtually identical estimates for a basic model. However, the structural equation modeling approach allowed more realistic assumptions on measurement errors and factor loadings, rendering better model fit indices.

  18. Translating building information modeling to building energy modeling using model view definition.

    Science.gov (United States)

    Jeong, WoonSeong; Kim, Jong Bum; Clayton, Mark J; Haberl, Jeff S; Yan, Wei

    2014-01-01

    This paper presents a new approach to translate between Building Information Modeling (BIM) and Building Energy Modeling (BEM) that uses Modelica, an object-oriented declarative, equation-based simulation environment. The approach (BIM2BEM) has been developed using a data modeling method to enable seamless model translations of building geometry, materials, and topology. Using data modeling, we created a Model View Definition (MVD) consisting of a process model and a class diagram. The process model demonstrates object-mapping between BIM and Modelica-based BEM (ModelicaBEM) and facilitates the definition of required information during model translations. The class diagram represents the information and object relationships to produce a class package intermediate between the BIM and BEM. The implementation of the intermediate class package enables system interface (Revit2Modelica) development for automatic BIM data translation into ModelicaBEM. In order to demonstrate and validate our approach, simulation result comparisons have been conducted via three test cases using (1) the BIM-based Modelica models generated from Revit2Modelica and (2) BEM models manually created using LBNL Modelica Buildings library. Our implementation shows that BIM2BEM (1) enables BIM models to be translated into ModelicaBEM models, (2) enables system interface development based on the MVD for thermal simulation, and (3) facilitates the reuse of original BIM data into building energy simulation without an import/export process.

  19. Translating Building Information Modeling to Building Energy Modeling Using Model View Definition

    Directory of Open Access Journals (Sweden)

    WoonSeong Jeong

    2014-01-01

    Full Text Available This paper presents a new approach to translate between Building Information Modeling (BIM and Building Energy Modeling (BEM that uses Modelica, an object-oriented declarative, equation-based simulation environment. The approach (BIM2BEM has been developed using a data modeling method to enable seamless model translations of building geometry, materials, and topology. Using data modeling, we created a Model View Definition (MVD consisting of a process model and a class diagram. The process model demonstrates object-mapping between BIM and Modelica-based BEM (ModelicaBEM and facilitates the definition of required information during model translations. The class diagram represents the information and object relationships to produce a class package intermediate between the BIM and BEM. The implementation of the intermediate class package enables system interface (Revit2Modelica development for automatic BIM data translation into ModelicaBEM. In order to demonstrate and validate our approach, simulation result comparisons have been conducted via three test cases using (1 the BIM-based Modelica models generated from Revit2Modelica and (2 BEM models manually created using LBNL Modelica Buildings library. Our implementation shows that BIM2BEM (1 enables BIM models to be translated into ModelicaBEM models, (2 enables system interface development based on the MVD for thermal simulation, and (3 facilitates the reuse of original BIM data into building energy simulation without an import/export process.

  20. Models Archive and ModelWeb at NSSDC

    Science.gov (United States)

    Bilitza, D.; Papitashvili, N.; King, J. H.

    2002-05-01

    In addition to its large data holdings, NASA's National Space Science Data Center (NSSDC) also maintains an archive of space physics models for public use (ftp://nssdcftp.gsfc.nasa.gov/models/). The more than 60 model entries cover a wide range of parameters from the atmosphere, to the ionosphere, to the magnetosphere, to the heliosphere. The models are primarily empirical models developed by the respective model authors based on long data records from ground and space experiments. An online model catalog (http://nssdc.gsfc.nasa.gov/space/model/) provides information about these and other models and links to the model software if available. We will briefly review the existing model holdings and highlight some of its usages and users. In response to a growing need by the user community, NSSDC began to develop web-interfaces for the most frequently requested models. These interfaces enable users to compute and plot model parameters online for the specific conditions that they are interested in. Currently included in the Modelweb system (http://nssdc.gsfc.nasa.gov/space/model/) are the following models: the International Reference Ionosphere (IRI) model, the Mass Spectrometer Incoherent Scatter (MSIS) E90 model, the International Geomagnetic Reference Field (IGRF) and the AP/AE-8 models for the radiation belt electrons and protons. User accesses to both systems have been steadily increasing over the last years with occasional spikes prior to large scientific meetings. The current monthly rate is between 5,000 to 10,000 accesses for either system; in February 2002 13,872 accesses were recorded to the Modelsweb and 7092 accesses to the models archive.

  1. Modelling the models

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    By analysing the production of mesons in the forward region of LHC proton-proton collisions, the LHCf collaboration has provided key information needed to calibrate extremely high-energy cosmic ray models.   Average transverse momentum (pT) as a function of rapidity loss ∆y. Black dots represent LHCf data and the red diamonds represent SPS experiment UA7 results. The predictions of hadronic interaction models are shown by open boxes (sibyll 2.1), open circles (qgsjet II-03) and open triangles (epos 1.99). Among these models, epos 1.99 shows the best overall agreement with the LHCf data. LHCf is dedicated to the measurement of neutral particles emitted at extremely small angles in the very forward region of LHC collisions. Two imaging calorimeters – Arm1 and Arm2 – take data 140 m either side of the ATLAS interaction point. “The physics goal of this type of analysis is to provide data for calibrating the hadron interaction models – the well-known &...

  2. Model Manipulation for End-User Modelers

    DEFF Research Database (Denmark)

    Acretoaie, Vlad

    , and transformations using their modeling notation and editor of choice. The VM* languages are implemented via a single execution engine, the VM* Runtime, built on top of the Henshin graph-based transformation engine. This approach combines the benefits of flexibility, maturity, and formality. To simplify model editor......End-user modelers are domain experts who create and use models as part of their work. They are typically not Software Engineers, and have little or no programming and meta-modeling experience. However, using model manipulation languages developed in the context of Model-Driven Engineering often...... requires such experience. These languages are therefore only used by a small subset of the modelers that could, in theory, benefit from them. The goals of this thesis are to substantiate this observation, introduce the concepts and tools required to overcome it, and provide empirical evidence in support...

  3. Modeling energy-economy interactions using integrated models

    International Nuclear Information System (INIS)

    Uyterlinde, M.A.

    1994-06-01

    Integrated models are defined as economic energy models that consist of several submodels, either coupled by an interface module, or embedded in one large model. These models can be used for energy policy analysis. Using integrated models yields the following benefits. They provide a framework in which energy-economy interactions can be better analyzed than in stand-alone models. Integrated models can represent both energy sector technological details, as well as the behaviour of the market and the role of prices. Furthermore, the combination of modeling methodologies in one model can compensate weaknesses of one approach with strengths of another. These advantages motivated this survey of the class of integrated models. The purpose of this literature survey therefore was to collect and to present information on integrated models. To carry out this task, several goals were identified. The first goal was to give an overview of what is reported on these models in general. The second one was to find and describe examples of such models. Other goals were to find out what kinds of models were used as component models, and to examine the linkage methodology. Solution methods and their convergence properties were also a subject of interest. The report has the following structure. In chapter 2, a 'conceptual framework' is given. In chapter 3 a number of integrated models is described. In a table, a complete overview is presented of all described models. Finally, in chapter 4, the report is summarized, and conclusions are drawn regarding the advantages and drawbacks of integrated models. 8 figs., 29 refs

  4. On the role of model structure in hydrological modeling : Understanding models

    NARCIS (Netherlands)

    Gharari, S.

    2016-01-01

    Modeling is an essential part of the science of hydrology. Models enable us to formulate what we know and perceive from the real world into a neat package. Rainfall-runoff models are abstract simplifications of how a catchment works. Within the research field of scientific rainfall-runoff modeling,

  5. Evolution of computational models in BioModels Database and the Physiome Model Repository.

    Science.gov (United States)

    Scharm, Martin; Gebhardt, Tom; Touré, Vasundra; Bagnacani, Andrea; Salehzadeh-Yazdi, Ali; Wolkenhauer, Olaf; Waltemath, Dagmar

    2018-04-12

    A useful model is one that is being (re)used. The development of a successful model does not finish with its publication. During reuse, models are being modified, i.e. expanded, corrected, and refined. Even small changes in the encoding of a model can, however, significantly affect its interpretation. Our motivation for the present study is to identify changes in models and make them transparent and traceable. We analysed 13734 models from BioModels Database and the Physiome Model Repository. For each model, we studied the frequencies and types of updates between its first and latest release. To demonstrate the impact of changes, we explored the history of a Repressilator model in BioModels Database. We observed continuous updates in the majority of models. Surprisingly, even the early models are still being modified. We furthermore detected that many updates target annotations, which improves the information one can gain from models. To support the analysis of changes in model repositories we developed MoSt, an online tool for visualisations of changes in models. The scripts used to generate the data and figures for this study are available from GitHub https://github.com/binfalse/BiVeS-StatsGenerator and as a Docker image at https://hub.docker.com/r/binfalse/bives-statsgenerator/ . The website https://most.bio.informatik.uni-rostock.de/ provides interactive access to model versions and their evolutionary statistics. The reuse of models is still impeded by a lack of trust and documentation. A detailed and transparent documentation of all aspects of the model, including its provenance, will improve this situation. Knowledge about a model's provenance can avoid the repetition of mistakes that others already faced. More insights are gained into how the system evolves from initial findings to a profound understanding. We argue that it is the responsibility of the maintainers of model repositories to offer transparent model provenance to their users.

  6. Model documentation report: Transportation sector model of the National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    This report documents the objectives, analytical approach and development of the National Energy Modeling System (NEMS) Transportation Model (TRAN). The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, model source code, and forecast results generated by the model. This document serves three purposes. First, it is a reference document providing a detailed description of TRAN for model analysts, users, and the public. Second, this report meets the legal requirements of the Energy Information Administration (EIA) to provide adequate documentation in support of its statistical and forecast reports (Public Law 93-275, 57(b)(1)). Third, it permits continuity in model development by providing documentation from which energy analysts can undertake model enhancements, data updates, and parameter refinements.

  7. Modeling complexes of modeled proteins.

    Science.gov (United States)

    Anishchenko, Ivan; Kundrotas, Petras J; Vakser, Ilya A

    2017-03-01

    Structural characterization of proteins is essential for understanding life processes at the molecular level. However, only a fraction of known proteins have experimentally determined structures. This fraction is even smaller for protein-protein complexes. Thus, structural modeling of protein-protein interactions (docking) primarily has to rely on modeled structures of the individual proteins, which typically are less accurate than the experimentally determined ones. Such "double" modeling is the Grand Challenge of structural reconstruction of the interactome. Yet it remains so far largely untested in a systematic way. We present a comprehensive validation of template-based and free docking on a set of 165 complexes, where each protein model has six levels of structural accuracy, from 1 to 6 Å C α RMSD. Many template-based docking predictions fall into acceptable quality category, according to the CAPRI criteria, even for highly inaccurate proteins (5-6 Å RMSD), although the number of such models (and, consequently, the docking success rate) drops significantly for models with RMSD > 4 Å. The results show that the existing docking methodologies can be successfully applied to protein models with a broad range of structural accuracy, and the template-based docking is much less sensitive to inaccuracies of protein models than the free docking. Proteins 2017; 85:470-478. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Modeling styles in business process modeling

    NARCIS (Netherlands)

    Pinggera, J.; Soffer, P.; Zugal, S.; Weber, B.; Weidlich, M.; Fahland, D.; Reijers, H.A.; Mendling, J.; Bider, I.; Halpin, T.; Krogstie, J.; Nurcan, S.; Proper, E.; Schmidt, R.; Soffer, P.; Wrycza, S.

    2012-01-01

    Research on quality issues of business process models has recently begun to explore the process of creating process models. As a consequence, the question arises whether different ways of creating process models exist. In this vein, we observed 115 students engaged in the act of modeling, recording

  9. Comparison: Binomial model and Black Scholes model

    Directory of Open Access Journals (Sweden)

    Amir Ahmad Dar

    2018-03-01

    Full Text Available The Binomial Model and the Black Scholes Model are the popular methods that are used to solve the option pricing problems. Binomial Model is a simple statistical method and Black Scholes model requires a solution of a stochastic differential equation. Pricing of European call and a put option is a very difficult method used by actuaries. The main goal of this study is to differentiate the Binominal model and the Black Scholes model by using two statistical model - t-test and Tukey model at one period. Finally, the result showed that there is no significant difference between the means of the European options by using the above two models.

  10. Modelling in Business Model design

    NARCIS (Netherlands)

    Simonse, W.L.

    2013-01-01

    It appears that business model design might not always produce a design or model as the expected result. However when designers are involved, a visual model or artefact is produced. To assist strategic managers in thinking about how they can act, the designers challenge is to combine strategy and

  11. Modelling SDL, Modelling Languages

    Directory of Open Access Journals (Sweden)

    Michael Piefel

    2007-02-01

    Full Text Available Today's software systems are too complex to implement them and model them using only one language. As a result, modern software engineering uses different languages for different levels of abstraction and different system aspects. Thus to handle an increasing number of related or integrated languages is the most challenging task in the development of tools. We use object oriented metamodelling to describe languages. Object orientation allows us to derive abstract reusable concept definitions (concept classes from existing languages. This language definition technique concentrates on semantic abstractions rather than syntactical peculiarities. We present a set of common concept classes that describe structure, behaviour, and data aspects of high-level modelling languages. Our models contain syntax modelling using the OMG MOF as well as static semantic constraints written in OMG OCL. We derive metamodels for subsets of SDL and UML from these common concepts, and we show for parts of these languages that they can be modelled and related to each other through the same abstract concepts.

  12. Model integration and a theory of models

    OpenAIRE

    Dolk, Daniel R.; Kottemann, Jeffrey E.

    1993-01-01

    Model integration extends the scope of model management to include the dimension of manipulation as well. This invariably leads to comparisons with database theory. Model integration is viewed from four perspectives: Organizational, definitional, procedural, and implementational. Strategic modeling is discussed as the organizational motivation for model integration. Schema and process integration are examined as the logical and manipulation counterparts of model integr...

  13. A new spin on nuclei

    International Nuclear Information System (INIS)

    Clark, R.; Wadsworth, B.

    1998-01-01

    Magnetic rotation is a new phenomenon that is forcing physicists to rethink their understanding of what goes on inside the nucleus The rotation of quantum objects has a long and distinguished history in physics. In 1912 the Danish scientist Niels Bjerrum was the first to recognize that the rotation of molecules is quantized. In 1938 Edward Teller and John Wheeler observed similar features in the spectra of excited nuclei, and suggested that this was caused by the nucleus rotating. But a more complete explanation had to wait until 1951, when Aage Bohr (the son of Niels) pointed out that rotation was a consequence of the nucleus deforming from its spherical shape. We owe much of our current understanding of nuclear rotation to the work of Bohr and Ben Mottelson, who shared the 1975 Nobel Prize for Physics with James Rainwater for developing a model of the nucleus that combined the individual and collective motions of the neutrons and protons inside the nucleus. What makes it possible for a nucleus to rotate? Quantum mechanically, a perfect sphere cannot rotate because it appears the same when viewed from any direction and there is no point of reference against which its change in position can be detected. To see the rotation the spherical symmetry must be broken to allow an orientation in space to be defined. For example, a diatomic molecule, which has a dumbbell shape, can rotate about the two axes perpendicular to its axis of symmetry. A quantum mechanical treatment of a diatomic molecule leads to a very simple relationship between rotational energy, E, and angular momentum. This energy is found to be proportional to J(J + 1), where J is the angular momentum quantum number. The molecule also has a magnetic moment that is proportional to J. These concepts can be applied to the atomic nucleus. If the distribution of mass and/or charge inside the nucleus becomes non-spherical then the nucleus will be able to rotate. The rotation is termed ''collective'' because many

  14. Integrated Site Model Process Model Report

    International Nuclear Information System (INIS)

    Booth, T.

    2000-01-01

    The Integrated Site Model (ISM) provides a framework for discussing the geologic features and properties of Yucca Mountain, which is being evaluated as a potential site for a geologic repository for the disposal of nuclear waste. The ISM is important to the evaluation of the site because it provides 3-D portrayals of site geologic, rock property, and mineralogic characteristics and their spatial variabilities. The ISM is not a single discrete model; rather, it is a set of static representations that provide three-dimensional (3-D), computer representations of site geology, selected hydrologic and rock properties, and mineralogic-characteristics data. These representations are manifested in three separate model components of the ISM: the Geologic Framework Model (GFM), the Rock Properties Model (RPM), and the Mineralogic Model (MM). The GFM provides a representation of the 3-D stratigraphy and geologic structure. Based on the framework provided by the GFM, the RPM and MM provide spatial simulations of the rock and hydrologic properties, and mineralogy, respectively. Functional summaries of the component models and their respective output are provided in Section 1.4. Each of the component models of the ISM considers different specific aspects of the site geologic setting. Each model was developed using unique methodologies and inputs, and the determination of the modeled units for each of the components is dependent on the requirements of that component. Therefore, while the ISM represents the integration of the rock properties and mineralogy into a geologic framework, the discussion of ISM construction and results is most appropriately presented in terms of the three separate components. This Process Model Report (PMR) summarizes the individual component models of the ISM (the GFM, RPM, and MM) and describes how the three components are constructed and combined to form the ISM

  15. Concept Modeling vs. Data modeling in Practice

    DEFF Research Database (Denmark)

    Madsen, Bodil Nistrup; Erdman Thomsen, Hanne

    2015-01-01

    This chapter shows the usefulness of terminological concept modeling as a first step in data modeling. First, we introduce terminological concept modeling with terminological ontologies, i.e. concept systems enriched with characteristics modeled as feature specifications. This enables a formal...... account of the inheritance of characteristics and allows us to introduce a number of principles and constraints which render concept modeling more coherent than earlier approaches. Second, we explain how terminological ontologies can be used as the basis for developing conceptual and logical data models....... We also show how to map from the various elements in the terminological ontology to elements in the data models, and explain the differences between the models. Finally the usefulness of terminological ontologies as a prerequisite for IT development and data modeling is illustrated with examples from...

  16. Automated Protein Structure Modeling with SWISS-MODEL Workspace and the Protein Model Portal

    OpenAIRE

    Bordoli, Lorenza; Schwede, Torsten

    2012-01-01

    Comparative protein structure modeling is a computational approach to build three-dimensional structural models for proteins using experimental structures of related protein family members as templates. Regular blind assessments of modeling accuracy have demonstrated that comparative protein structure modeling is currently the most reliable technique to model protein structures. Homology models are often sufficiently accurate to substitute for experimental structures in a wide variety of appl...

  17. Determination of Soil Moisture Content using Laboratory Experimental and Field Electrical Resistivity Values

    Science.gov (United States)

    Hazreek, Z. A. M.; Rosli, S.; Fauziah, A.; Wijeyesekera, D. C.; Ashraf, M. I. M.; Faizal, T. B. M.; Kamarudin, A. F.; Rais, Y.; Dan, M. F. Md; Azhar, A. T. S.; Hafiz, Z. M.

    2018-04-01

    The efficiency of civil engineering structure require comprehensive geotechnical data obtained from site investigation. In the past, conventional site investigation was heavily related to drilling techniques thus suffer from several limitations such as time consuming, expensive and limited data collection. Consequently, this study presents determination of soil moisture content using laboratory experimental and field electrical resistivity values (ERV). Field and laboratory electrical resistivity (ER) test were performed using ABEM SAS4000 and Nilsson400 soil resistance meter. Soil sample used for resistivity test was tested for characterization test specifically on particle size distribution and moisture content test according to BS1377 (1990). Field ER data was processed using RES2DINV software while laboratory ER data was analyzed using SPSS and Excel software. Correlation of ERV and moisture content shows some medium relationship due to its r = 0.506. Moreover, coefficient of determination, R2 analyzed has demonstrate that the statistical correlation obtain was very good due to its R2 value of 0.9382. In order to determine soil moisture content based on statistical correlation (w = 110.68ρ-0.347), correction factor, C was established through laboratory and field ERV given as 19.27. Finally, this study has shown that soil basic geotechnical properties with particular reference to water content was applicably determined using integration of laboratory and field ERV data analysis thus able to compliment conventional approach due to its economic, fast and wider data coverage.

  18. Model documentation report: Transportation sector model of the National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    Over the past year, several modifications have been made to the NEMS Transportation Model, incorporating greater levels of detail and analysis in modules previously represented in the aggregate or under a profusion of simplifying assumptions. This document is intended to amend those sections of the Model Documentation Report (MDR) which describe these superseded modules. Significant changes have been implemented in the LDV Fuel Economy Model, the Alternative Fuel Vehicle Model, the LDV Fleet Module, and the Highway Freight Model. The relevant sections of the MDR have been extracted from the original document, amended, and are presented in the following pages. A brief summary of the modifications follows: In the Fuel Economy Model, modifications have been made which permit the user to employ more optimistic assumptions about the commercial viability and impact of selected technological improvements. This model also explicitly calculates the fuel economy of an array of alternative fuel vehicles (AFV`s) which are subsequently used in the estimation of vehicle sales. In the Alternative Fuel Vehicle Model, the results of the Fuel Economy Model have been incorporated, and the program flows have been modified to reflect that fact. In the Light Duty Vehicle Fleet Module, the sales of vehicles to fleets of various size are endogenously calculated in order to provide a more detailed estimate of the impacts of EPACT legislation on the sales of AFV`s to fleets. In the Highway Freight Model, the previous aggregate estimation has been replaced by a detailed Freight Truck Stock Model, where travel patterns, efficiencies, and energy intensities are estimated by industrial grouping. Several appendices are provided at the end of this document, containing data tables and supplementary descriptions of the model development process which are not integral to an understanding of the overall model structure.

  19. The IMACLIM model; Le modele IMACLIM

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This document provides annexes to the IMACLIM model which propose an actualized description of IMACLIM, model allowing the design of an evaluation tool of the greenhouse gases reduction policies. The model is described in a version coupled with the POLES, technical and economical model of the energy industry. Notations, equations, sources, processing and specifications are proposed and detailed. (A.L.B.)

  20. Modelling Practice

    DEFF Research Database (Denmark)

    Cameron, Ian; Gani, Rafiqul

    2011-01-01

    This chapter deals with the practicalities of building, testing, deploying and maintaining models. It gives specific advice for each phase of the modelling cycle. To do this, a modelling framework is introduced which covers: problem and model definition; model conceptualization; model data...... requirements; model construction; model solution; model verification; model validation and finally model deployment and maintenance. Within the adopted methodology, each step is discussedthrough the consideration of key issues and questions relevant to the modelling activity. Practical advice, based on many...

  1. Leadership Models.

    Science.gov (United States)

    Freeman, Thomas J.

    This paper discusses six different models of organizational structure and leadership, including the scalar chain or pyramid model, the continuum model, the grid model, the linking pin model, the contingency model, and the circle or democratic model. Each model is examined in a separate section that describes the model and its development, lists…

  2. Cognitive models embedded in system simulation models

    International Nuclear Information System (INIS)

    Siegel, A.I.; Wolf, J.J.

    1982-01-01

    If we are to discuss and consider cognitive models, we must first come to grips with two questions: (1) What is cognition; (2) What is a model. Presumably, the answers to these questions can provide a basis for defining a cognitive model. Accordingly, this paper first places these two questions into perspective. Then, cognitive models are set within the context of computer simulation models and a number of computer simulations of cognitive processes are described. Finally, pervasive issues are discussed vis-a-vis cognitive modeling in the computer simulation context

  3. Better models are more effectively connected models

    Science.gov (United States)

    Nunes, João Pedro; Bielders, Charles; Darboux, Frederic; Fiener, Peter; Finger, David; Turnbull-Lloyd, Laura; Wainwright, John

    2016-04-01

    The concept of hydrologic and geomorphologic connectivity describes the processes and pathways which link sources (e.g. rainfall, snow and ice melt, springs, eroded areas and barren lands) to accumulation areas (e.g. foot slopes, streams, aquifers, reservoirs), and the spatial variations thereof. There are many examples of hydrological and sediment connectivity on a watershed scale; in consequence, a process-based understanding of connectivity is crucial to help managers understand their systems and adopt adequate measures for flood prevention, pollution mitigation and soil protection, among others. Modelling is often used as a tool to understand and predict fluxes within a catchment by complementing observations with model results. Catchment models should therefore be able to reproduce the linkages, and thus the connectivity of water and sediment fluxes within the systems under simulation. In modelling, a high level of spatial and temporal detail is desirable to ensure taking into account a maximum number of components, which then enables connectivity to emerge from the simulated structures and functions. However, computational constraints and, in many cases, lack of data prevent the representation of all relevant processes and spatial/temporal variability in most models. In most cases, therefore, the level of detail selected for modelling is too coarse to represent the system in a way in which connectivity can emerge; a problem which can be circumvented by representing fine-scale structures and processes within coarser scale models using a variety of approaches. This poster focuses on the results of ongoing discussions on modelling connectivity held during several workshops within COST Action Connecteur. It assesses the current state of the art of incorporating the concept of connectivity in hydrological and sediment models, as well as the attitudes of modellers towards this issue. The discussion will focus on the different approaches through which connectivity

  4. Constructive Epistemic Modeling: A Hierarchical Bayesian Model Averaging Method

    Science.gov (United States)

    Tsai, F. T. C.; Elshall, A. S.

    2014-12-01

    Constructive epistemic modeling is the idea that our understanding of a natural system through a scientific model is a mental construct that continually develops through learning about and from the model. Using the hierarchical Bayesian model averaging (HBMA) method [1], this study shows that segregating different uncertain model components through a BMA tree of posterior model probabilities, model prediction, within-model variance, between-model variance and total model variance serves as a learning tool [2]. First, the BMA tree of posterior model probabilities permits the comparative evaluation of the candidate propositions of each uncertain model component. Second, systemic model dissection is imperative for understanding the individual contribution of each uncertain model component to the model prediction and variance. Third, the hierarchical representation of the between-model variance facilitates the prioritization of the contribution of each uncertain model component to the overall model uncertainty. We illustrate these concepts using the groundwater modeling of a siliciclastic aquifer-fault system. The sources of uncertainty considered are from geological architecture, formation dip, boundary conditions and model parameters. The study shows that the HBMA analysis helps in advancing knowledge about the model rather than forcing the model to fit a particularly understanding or merely averaging several candidate models. [1] Tsai, F. T.-C., and A. S. Elshall (2013), Hierarchical Bayesian model averaging for hydrostratigraphic modeling: Uncertainty segregation and comparative evaluation. Water Resources Research, 49, 5520-5536, doi:10.1002/wrcr.20428. [2] Elshall, A.S., and F. T.-C. Tsai (2014). Constructive epistemic modeling of groundwater flow with geological architecture and boundary condition uncertainty under Bayesian paradigm, Journal of Hydrology, 517, 105-119, doi: 10.1016/j.jhydrol.2014.05.027.

  5. Models and role models

    NARCIS (Netherlands)

    ten Cate, J.M.

    2015-01-01

    Developing experimental models to understand dental caries has been the theme in our research group. Our first, the pH-cycling model, was developed to investigate the chemical reactions in enamel or dentine, which lead to dental caries. It aimed to leverage our understanding of the fluoride mode of

  6. Multiscale musculoskeletal modelling, data–model fusion and electromyography-informed modelling

    Science.gov (United States)

    Zhang, J.; Heidlauf, T.; Sartori, M.; Besier, T.; Röhrle, O.; Lloyd, D.

    2016-01-01

    This paper proposes methods and technologies that advance the state of the art for modelling the musculoskeletal system across the spatial and temporal scales; and storing these using efficient ontologies and tools. We present population-based modelling as an efficient method to rapidly generate individual morphology from only a few measurements and to learn from the ever-increasing supply of imaging data available. We present multiscale methods for continuum muscle and bone models; and efficient mechanostatistical methods, both continuum and particle-based, to bridge the scales. Finally, we examine both the importance that muscles play in bone remodelling stimuli and the latest muscle force prediction methods that use electromyography-assisted modelling techniques to compute musculoskeletal forces that best reflect the underlying neuromuscular activity. Our proposal is that, in order to have a clinically relevant virtual physiological human, (i) bone and muscle mechanics must be considered together; (ii) models should be trained on population data to permit rapid generation and use underlying principal modes that describe both muscle patterns and morphology; and (iii) these tools need to be available in an open-source repository so that the scientific community may use, personalize and contribute to the database of models. PMID:27051510

  7. Atmospheric statistical dynamic models. Model performance: the Lawrence Livermore Laboratoy Zonal Atmospheric Model

    International Nuclear Information System (INIS)

    Potter, G.L.; Ellsaesser, H.W.; MacCracken, M.C.; Luther, F.M.

    1978-06-01

    Results from the zonal model indicate quite reasonable agreement with observation in terms of the parameters and processes that influence the radiation and energy balance calculations. The model produces zonal statistics similar to those from general circulation models, and has also been shown to produce similar responses in sensitivity studies. Further studies of model performance are planned, including: comparison with July data; comparison of temperature and moisture transport and wind fields for winter and summer months; and a tabulation of atmospheric energetics. Based on these preliminary performance studies, however, it appears that the zonal model can be used in conjunction with more complex models to help unravel the problems of understanding the processes governing present climate and climate change. As can be seen in the subsequent paper on model sensitivity studies, in addition to reduced cost of computation, the zonal model facilitates analysis of feedback mechanisms and simplifies analysis of the interactions between processes

  8. Gradient-based model calibration with proxy-model assistance

    Science.gov (United States)

    Burrows, Wesley; Doherty, John

    2016-02-01

    Use of a proxy model in gradient-based calibration and uncertainty analysis of a complex groundwater model with large run times and problematic numerical behaviour is described. The methodology is general, and can be used with models of all types. The proxy model is based on a series of analytical functions that link all model outputs used in the calibration process to all parameters requiring estimation. In enforcing history-matching constraints during the calibration and post-calibration uncertainty analysis processes, the proxy model is run for the purposes of populating the Jacobian matrix, while the original model is run when testing parameter upgrades; the latter process is readily parallelized. Use of a proxy model in this fashion dramatically reduces the computational burden of complex model calibration and uncertainty analysis. At the same time, the effect of model numerical misbehaviour on calculation of local gradients is mitigated, this allowing access to the benefits of gradient-based analysis where lack of integrity in finite-difference derivatives calculation would otherwise have impeded such access. Construction of a proxy model, and its subsequent use in calibration of a complex model, and in analysing the uncertainties of predictions made by that model, is implemented in the PEST suite.

  9. Spike Neural Models Part II: Abstract Neural Models

    Directory of Open Access Journals (Sweden)

    Johnson, Melissa G.

    2018-02-01

    Full Text Available Neurons are complex cells that require a lot of time and resources to model completely. In spiking neural networks (SNN though, not all that complexity is required. Therefore simple, abstract models are often used. These models save time, use less computer resources, and are easier to understand. This tutorial presents two such models: Izhikevich's model, which is biologically realistic in the resulting spike trains but not in the parameters, and the Leaky Integrate and Fire (LIF model which is not biologically realistic but does quickly and easily integrate input to produce spikes. Izhikevich's model is based on Hodgkin-Huxley's model but simplified such that it uses only two differentiation equations and four parameters to produce various realistic spike patterns. LIF is based on a standard electrical circuit and contains one equation. Either of these two models, or any of the many other models in literature can be used in a SNN. Choosing a neural model is an important task that depends on the goal of the research and the resources available. Once a model is chosen, network decisions such as connectivity, delay, and sparseness, need to be made. Understanding neural models and how they are incorporated into the network is the first step in creating a SNN.

  10. Population balance models: a useful complementary modelling framework for future WWTP modelling

    DEFF Research Database (Denmark)

    Nopens, Ingmar; Torfs, Elena; Ducoste, Joel

    2015-01-01

    Population balance models (PBMs) represent a powerful modelling framework for the description of the dynamics of properties that are characterised by distributions. This distribution of properties under transient conditions has been demonstrated in many chemical engineering applications. Modelling...

  11. From Product Models to Product State Models

    DEFF Research Database (Denmark)

    Larsen, Michael Holm

    1999-01-01

    A well-known technology designed to handle product data is Product Models. Product Models are in their current form not able to handle all types of product state information. Hence, the concept of a Product State Model (PSM) is proposed. The PSM and in particular how to model a PSM is the Research...

  12. North American Carbon Project (NACP) Regional Model-Model and Model-Data Intercomparison Project

    Science.gov (United States)

    Huntzinger, D. N.; Post, W. M.; Jacobson, A. R.; Cook, R. B.

    2009-05-01

    Available observations are localized and widely separated in both space and time, so we depend heavily on models to characterize, understand, and predict carbon fluxes at regional and global scales. The results from each model differ because they use different approaches (forward vs. inverse), modeling strategies (detailed process, statistical, observation based), process representation, boundary conditions, initial conditions, and driver data. To investigate these differences we conducted a model-model and model-data comparison using available forward ecosystem model and atmospheric inverse output, along with regional scale inventory data. Forward or "bottom-up" models typically estimate carbon fluxes through a set of physiological relationships, and are based on our current mechanistic understanding of how carbon is exchanged within ecosystems. Inverse or "top-down" analyses use measured atmospheric concentrations of CO2, coupled with an atmospheric transport model to infer surface flux distributions. Although bottom-up models do fairly well at reproducing measured fluxes (i.e., net ecosystem exchange) at a given location, they vary considerably in their estimates of carbon flux over regional or continental scales, suggesting difficulty in scaling mechanistic relationships to large areas and/or timescales. Conversely, top-down inverse models predict fluxes that are quantitatively consistent with atmospheric measurements, suggesting that they are capturing large scale variability in flux quite well, but offer limited insights into the processes controlling this variability and how fluxes vary at fine spatial scales. The analyses focused on identifying and quantifying spatial and temporal patterns of carbon fluxes among the models; quantifying across-model variability, as well as comparing simulated or estimated surface fluxes and biomass to observed values at regional to continental scales for the period 2000-2005. The analysis focused on the following three

  13. Neuropeptides and nitric oxide synthase in the gill and the air-breathing organs of fishes.

    Science.gov (United States)

    Zaccone, Giacomo; Mauceri, Angela; Fasulo, Salvatore

    2006-05-01

    Anatomical and histochemical studies have demonstrated that the bulk of autonomic neurotransmission in fish gill is attributed to cholinergic and adrenergic mechanisms (Nilsson. 1984. In: Hoar WS, Randall DJ, editors. Fish physiology, Vol. XA. Orlando: Academic Press. p 185-227; Donald. 1998. In: Evans DH, editor. The physiology of fishes, 2nd edition. Boca Raton: CRC Press. p 407-439). In many tissues, blockade of adrenergic and cholinergic transmission results in residual responses to nerve stimulation, which are termed NonAdrenergic, NonCholinergic (NANC). The discovery of nitric oxide (NO) has provided a basis for explaining many examples of NANC transmissions with accumulated physiological and pharmacological data indicating its function as a primary NANC transmitter. Little is known about the NANC neurotransmission, and studies on neuropeptides and NOS (Nitric Oxide Synthase) are very fragmentary in the gill and the air-breathing organs of fishes. Knowledge of the distribution of nerves and effects of perfusing agonists may help to understand the mechanisms of perfusion regulation in the gill (Olson. 2002. J Exp Zool 293:214-231). Air breathing as a mechanism for acquiring oxygen has evolved independently in several groups of fishes, necessitating modifications of the organs responsible for the exchange of gases. Aquatic hypoxia in freshwaters has been probably the more important selective force in the evolution of air breathing in vertebrates. Fishes respire with gills that are complex structures with many different effectors and potential control systems. Autonomic innervation of the gill has received considerable attention. An excellent review on branchial innervation includes Sundin and Nilsson's (2002. J Exp Zool 293:232-248) with an emphasis on the anatomy and basic functioning of afferent and efferent fibers of the branchial nerves. The chapters by Evans (2002. J Exp Zool 293:336-347) and Olson (2002) provide new challenges about a variety of

  14. Population Balance Models: A useful complementary modelling framework for future WWTP modelling

    DEFF Research Database (Denmark)

    Nopens, Ingmar; Torfs, Elena; Ducoste, Joel

    2014-01-01

    Population Balance Models (PBMs) represent a powerful modelling framework for the description of the dynamics of properties that are characterised by statistical distributions. This has been demonstrated in many chemical engineering applications. Modelling efforts of several current and future unit...

  15. Model Metric untuk Mengukur Fleksibilitas Model Proses Bisnis

    Directory of Open Access Journals (Sweden)

    Endang Wahyu Pamungkas

    2014-10-01

    Full Text Available Abstrak Organisasi bisnis dunia saat ini banyak memanfaatkan sistem informasi digital untuk memberikan pemahaman mengenai manajemen proses bisnis yang mereka jalani. Pemanfaatan sistem Enterprise Resource Planning (ERP merupakan contoh teknologi dalam manajemen proses bisnis. Melalui sistem ini perusahaan dapat membangun dan mengembangkan proses bisnis. Selain itu, perusahaan juga dapat menyesuaikan proses bisnis secara cepat terhadap perubahan yang terjadi seiring bertambahnya kebutuhan dan informasi, berubahnya kondisi pasar, atau perubahan kebijakan. Sehubungan dengan perubahan proses bisnis yang sering terjadi, maka aspek fleksibilitas terhadap model proses yang dibangun harus ditingkatkan. Dalam mendukung peningkatan fleksibilitas tersebut tentunya dibutuhkan sebuah model untuk mengukur tingkat flesibelitas model proses bisnis. Model tersebut yang kemudian dapat digunakan oleh analis untuk melakukan perbandingan sehingga dapat diperoleh model proses bisnis yang paling fleksibel dan cocok dengan perusahaan. Hal ini dapat dianalisa dengan melibatkan aspek-aspek fleksibel yang telah diteliti pada penelitian-penelitian sebelumnya. Dalam paper ini akan dilakukan penelitian mengenai aspek fleksibitas dalam model proses bisnis untuk menghasilkan model metric yang dapat melakukan kuantifikasi tingkat fleksibilitas pada model proses bisnis. Model metric yang dihasilkan pada penelitian ini mampu melakukan perhitungan fleksibelitas pada model proses bisnis secara kuantitatif. Kata kunci: ERP, fleksibilitas, metadata, model metric, model proses bisnis, variasi Abstract Recently, business organizations in the world are making use of digital information systems to provide an understanding of the business process management in which they live. Utilization of Enterprise Resource Planning (ERP system is an example of technology in business process management. Through this system, some companies can build and develop business process and can quickly adjust

  16. Modelling bankruptcy prediction models in Slovak companies

    Directory of Open Access Journals (Sweden)

    Kovacova Maria

    2017-01-01

    Full Text Available An intensive research from academics and practitioners has been provided regarding models for bankruptcy prediction and credit risk management. In spite of numerous researches focusing on forecasting bankruptcy using traditional statistics techniques (e.g. discriminant analysis and logistic regression and early artificial intelligence models (e.g. artificial neural networks, there is a trend for transition to machine learning models (support vector machines, bagging, boosting, and random forest to predict bankruptcy one year prior to the event. Comparing the performance of this with unconventional approach with results obtained by discriminant analysis, logistic regression, and neural networks application, it has been found that bagging, boosting, and random forest models outperform the others techniques, and that all prediction accuracy in the testing sample improves when the additional variables are included. On the other side the prediction accuracy of old and well known bankruptcy prediction models is quiet high. Therefore, we aim to analyse these in some way old models on the dataset of Slovak companies to validate their prediction ability in specific conditions. Furthermore, these models will be modelled according to new trends by calculating the influence of elimination of selected variables on the overall prediction ability of these models.

  17. The ModelCC Model-Driven Parser Generator

    Directory of Open Access Journals (Sweden)

    Fernando Berzal

    2015-01-01

    Full Text Available Syntax-directed translation tools require the specification of a language by means of a formal grammar. This grammar must conform to the specific requirements of the parser generator to be used. This grammar is then annotated with semantic actions for the resulting system to perform its desired function. In this paper, we introduce ModelCC, a model-based parser generator that decouples language specification from language processing, avoiding some of the problems caused by grammar-driven parser generators. ModelCC receives a conceptual model as input, along with constraints that annotate it. It is then able to create a parser for the desired textual syntax and the generated parser fully automates the instantiation of the language conceptual model. ModelCC also includes a reference resolution mechanism so that ModelCC is able to instantiate abstract syntax graphs, rather than mere abstract syntax trees.

  18. Environmental Satellite Models for a Macroeconomic Model

    International Nuclear Information System (INIS)

    Moeller, F.; Grinderslev, D.; Werner, M.

    2003-01-01

    To support national environmental policy, it is desirable to forecast and analyse environmental indicators consistently with economic variables. However, environmental indicators are physical measures linked to physical activities that are not specified in economic models. One way to deal with this is to develop environmental satellite models linked to economic models. The system of models presented gives a frame of reference where emissions of greenhouse gases, acid gases, and leaching of nutrients to the aquatic environment are analysed in line with - and consistently with - macroeconomic variables. This paper gives an overview of the data and the satellite models. Finally, the results of applying the model system to calculate the impacts on emissions and the economy are reviewed in a few illustrative examples. The models have been developed for Denmark; however, most of the environmental data used are from the CORINAIR system implemented in numerous countries

  19. A model evaluation checklist for process-based environmental models

    Science.gov (United States)

    Jackson-Blake, Leah

    2015-04-01

    Mechanistic catchment-scale phosphorus models appear to perform poorly where diffuse sources dominate. The reasons for this were investigated for one commonly-applied model, the INtegrated model of CAtchment Phosphorus (INCA-P). Model output was compared to 18 months of daily water quality monitoring data in a small agricultural catchment in Scotland, and model structure, key model processes and internal model responses were examined. Although the model broadly reproduced dissolved phosphorus dynamics, it struggled with particulates. The reasons for poor performance were explored, together with ways in which improvements could be made. The process of critiquing and assessing model performance was then generalised to provide a broadly-applicable model evaluation checklist, incorporating: (1) Calibration challenges, relating to difficulties in thoroughly searching a high-dimensional parameter space and in selecting appropriate means of evaluating model performance. In this study, for example, model simplification was identified as a necessary improvement to reduce the number of parameters requiring calibration, whilst the traditionally-used Nash Sutcliffe model performance statistic was not able to discriminate between realistic and unrealistic model simulations, and alternative statistics were needed. (2) Data limitations, relating to a lack of (or uncertainty in) input data, data to constrain model parameters, data for model calibration and testing, and data to test internal model processes. In this study, model reliability could be improved by addressing all four kinds of data limitation. For example, there was insufficient surface water monitoring data for model testing against an independent dataset to that used in calibration, whilst additional monitoring of groundwater and effluent phosphorus inputs would help distinguish between alternative plausible model parameterisations. (3) Model structural inadequacies, whereby model structure may inadequately represent

  20. Coupling Climate Models and Forward-Looking Economic Models

    Science.gov (United States)

    Judd, K.; Brock, W. A.

    2010-12-01

    Authors: Dr. Kenneth L. Judd, Hoover Institution, and Prof. William A. Brock, University of Wisconsin Current climate models range from General Circulation Models (GCM’s) with millions of degrees of freedom to models with few degrees of freedom. Simple Energy Balance Climate Models (EBCM’s) help us understand the dynamics of GCM’s. The same is true in economics with Computable General Equilibrium Models (CGE’s) where some models are infinite-dimensional multidimensional differential equations but some are simple models. Nordhaus (2007, 2010) couples a simple EBCM with a simple economic model. One- and two- dimensional ECBM’s do better at approximating damages across the globe and positive and negative feedbacks from anthroprogenic forcing (North etal. (1981), Wu and North (2007)). A proper coupling of climate and economic systems is crucial for arriving at effective policies. Brock and Xepapadeas (2010) have used Fourier/Legendre based expansions to study the shape of socially optimal carbon taxes over time at the planetary level in the face of damages caused by polar ice cap melt (as discussed by Oppenheimer, 2005) but in only a “one dimensional” EBCM. Economists have used orthogonal polynomial expansions to solve dynamic, forward-looking economic models (Judd, 1992, 1998). This presentation will couple EBCM climate models with basic forward-looking economic models, and examine the effectiveness and scaling properties of alternative solution methods. We will use a two dimensional EBCM model on the sphere (Wu and North, 2007) and a multicountry, multisector regional model of the economic system. Our aim will be to gain insights into intertemporal shape of the optimal carbon tax schedule, and its impact on global food production, as modeled by Golub and Hertel (2009). We will initially have limited computing resources and will need to focus on highly aggregated models. However, this will be more complex than existing models with forward

  1. EIA model documentation: Petroleum Market Model of the National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-30

    The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. Documentation of the model is in accordance with EIA`s legal obligation to provide adequate documentation in support of its models (Public Law 94-385, section 57.b.2). The PMM models petroleum refining activities, the marketing of products, the production of natural gas liquids and domestic methanol, projects petroleum provides and sources of supplies for meeting demand. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption.

  2. Modeling Methods

    Science.gov (United States)

    Healy, Richard W.; Scanlon, Bridget R.

    2010-01-01

    Simulation models are widely used in all types of hydrologic studies, and many of these models can be used to estimate recharge. Models can provide important insight into the functioning of hydrologic systems by identifying factors that influence recharge. The predictive capability of models can be used to evaluate how changes in climate, water use, land use, and other factors may affect recharge rates. Most hydrological simulation models, including watershed models and groundwater-flow models, are based on some form of water-budget equation, so the material in this chapter is closely linked to that in Chapter 2. Empirical models that are not based on a water-budget equation have also been used for estimating recharge; these models generally take the form of simple estimation equations that define annual recharge as a function of precipitation and possibly other climatic data or watershed characteristics.Model complexity varies greatly. Some models are simple accounting models; others attempt to accurately represent the physics of water movement through each compartment of the hydrologic system. Some models provide estimates of recharge explicitly; for example, a model based on the Richards equation can simulate water movement from the soil surface through the unsaturated zone to the water table. Recharge estimates can be obtained indirectly from other models. For example, recharge is a parameter in groundwater-flow models that solve for hydraulic head (i.e. groundwater level). Recharge estimates can be obtained through a model calibration process in which recharge and other model parameter values are adjusted so that simulated water levels agree with measured water levels. The simulation that provides the closest agreement is called the best fit, and the recharge value used in that simulation is the model-generated estimate of recharge.

  3. Post-model selection inference and model averaging

    Directory of Open Access Journals (Sweden)

    Georges Nguefack-Tsague

    2011-07-01

    Full Text Available Although model selection is routinely used in practice nowadays, little is known about its precise effects on any subsequent inference that is carried out. The same goes for the effects induced by the closely related technique of model averaging. This paper is concerned with the use of the same data first to select a model and then to carry out inference, in particular point estimation and point prediction. The properties of the resulting estimator, called a post-model-selection estimator (PMSE, are hard to derive. Using selection criteria such as hypothesis testing, AIC, BIC, HQ and Cp, we illustrate that, in terms of risk function, no single PMSE dominates the others. The same conclusion holds more generally for any penalised likelihood information criterion. We also compare various model averaging schemes and show that no single one dominates the others in terms of risk function. Since PMSEs can be regarded as a special case of model averaging, with 0-1 random-weights, we propose a connection between the two theories, in the frequentist approach, by taking account of the selection procedure when performing model averaging. We illustrate the point by simulating a simple linear regression model.

  4. The DINA model as a constrained general diagnostic model: Two variants of a model equivalency.

    Science.gov (United States)

    von Davier, Matthias

    2014-02-01

    The 'deterministic-input noisy-AND' (DINA) model is one of the more frequently applied diagnostic classification models for binary observed responses and binary latent variables. The purpose of this paper is to show that the model is equivalent to a special case of a more general compensatory family of diagnostic models. Two equivalencies are presented. Both project the original DINA skill space and design Q-matrix using mappings into a transformed skill space as well as a transformed Q-matrix space. Both variants of the equivalency produce a compensatory model that is mathematically equivalent to the (conjunctive) DINA model. This equivalency holds for all DINA models with any type of Q-matrix, not only for trivial (simple-structure) cases. The two versions of the equivalency presented in this paper are not implied by the recently suggested log-linear cognitive diagnosis model or the generalized DINA approach. The equivalencies presented here exist independent of these recently derived models since they solely require a linear - compensatory - general diagnostic model without any skill interaction terms. Whenever it can be shown that one model can be viewed as a special case of another more general one, conclusions derived from any particular model-based estimates are drawn into question. It is widely known that multidimensional models can often be specified in multiple ways while the model-based probabilities of observed variables stay the same. This paper goes beyond this type of equivalency by showing that a conjunctive diagnostic classification model can be expressed as a constrained special case of a general compensatory diagnostic modelling framework. © 2013 The British Psychological Society.

  5. Performance Measurement Model A TarBase model with ...

    Indian Academy of Sciences (India)

    rohit

    Model A 8.0 2.0 94.52% 88.46% 76 108 12 12 0.86 0.91 0.78 0.94. Model B 2.0 2.0 93.18% 89.33% 64 95 10 9 0.88 0.90 0.75 0.98. The above results for TEST – 1 show details for our two models (Model A and Model B).Performance of Model A after adding of 32 negative dataset of MiRTif on our testing set(MiRecords) ...

  6. Underground economy modelling: simple models with complicated dynamics

    OpenAIRE

    Albu, Lucian-Liviu

    2003-01-01

    The paper aims to model the underground economy using two different models: one based on the labor supply method and a generalized model for the allocation of time. The model based on the labor supply method is conceived as a simulating one in order to determine some reasonable thresholds of the underground sector extension based only on the available macroeconomic statistical data. The generalized model for the allocation of time is a model based on direct approach which estimates the underg...

  7. Integrative structure modeling with the Integrative Modeling Platform.

    Science.gov (United States)

    Webb, Benjamin; Viswanath, Shruthi; Bonomi, Massimiliano; Pellarin, Riccardo; Greenberg, Charles H; Saltzberg, Daniel; Sali, Andrej

    2018-01-01

    Building models of a biological system that are consistent with the myriad data available is one of the key challenges in biology. Modeling the structure and dynamics of macromolecular assemblies, for example, can give insights into how biological systems work, evolved, might be controlled, and even designed. Integrative structure modeling casts the building of structural models as a computational optimization problem, for which information about the assembly is encoded into a scoring function that evaluates candidate models. Here, we describe our open source software suite for integrative structure modeling, Integrative Modeling Platform (https://integrativemodeling.org), and demonstrate its use. © 2017 The Protein Society.

  8. Modeling volatility using state space models.

    Science.gov (United States)

    Timmer, J; Weigend, A S

    1997-08-01

    In time series problems, noise can be divided into two categories: dynamic noise which drives the process, and observational noise which is added in the measurement process, but does not influence future values of the system. In this framework, we show that empirical volatilities (the squared relative returns of prices) exhibit a significant amount of observational noise. To model and predict their time evolution adequately, we estimate state space models that explicitly include observational noise. We obtain relaxation times for shocks in the logarithm of volatility ranging from three weeks (for foreign exchange) to three to five months (for stock indices). In most cases, a two-dimensional hidden state is required to yield residuals that are consistent with white noise. We compare these results with ordinary autoregressive models (without a hidden state) and find that autoregressive models underestimate the relaxation times by about two orders of magnitude since they do not distinguish between observational and dynamic noise. This new interpretation of the dynamics of volatility in terms of relaxators in a state space model carries over to stochastic volatility models and to GARCH models, and is useful for several problems in finance, including risk management and the pricing of derivative securities. Data sets used: Olsen & Associates high frequency DEM/USD foreign exchange rates (8 years). Nikkei 225 index (40 years). Dow Jones Industrial Average (25 years).

  9. Document Models

    Directory of Open Access Journals (Sweden)

    A.A. Malykh

    2017-08-01

    Full Text Available In this paper, the concept of locally simple models is considered. Locally simple models are arbitrarily complex models built from relatively simple components. A lot of practically important domains of discourse can be described as locally simple models, for example, business models of enterprises and companies. Up to now, research in human reasoning automation has been mainly concentrated around the most intellectually intensive activities, such as automated theorem proving. On the other hand, the retailer business model is formed from ”jobs”, and each ”job” can be modelled and automated more or less easily. At the same time, the whole retailer model as an integrated system is extremely complex. In this paper, we offer a variant of the mathematical definition of a locally simple model. This definition is intended for modelling a wide range of domains. Therefore, we also must take into account the perceptual and psychological issues. Logic is elitist, and if we want to attract to our models as many people as possible, we need to hide this elitism behind some metaphor, to which ’ordinary’ people are accustomed. As such a metaphor, we use the concept of a document, so our locally simple models are called document models. Document models are built in the paradigm of semantic programming. This allows us to achieve another important goal - to make the documentary models executable. Executable models are models that can act as practical information systems in the described domain of discourse. Thus, if our model is executable, then programming becomes redundant. The direct use of a model, instead of its programming coding, brings important advantages, for example, a drastic cost reduction for development and maintenance. Moreover, since the model is well and sound, and not dissolved within programming modules, we can directly apply AI tools, in particular, machine learning. This significantly expands the possibilities for automation and

  10. An online model composition tool for system biology models.

    Science.gov (United States)

    Coskun, Sarp A; Cicek, A Ercument; Lai, Nicola; Dash, Ranjan K; Ozsoyoglu, Z Meral; Ozsoyoglu, Gultekin

    2013-09-05

    There are multiple representation formats for Systems Biology computational models, and the Systems Biology Markup Language (SBML) is one of the most widely used. SBML is used to capture, store, and distribute computational models by Systems Biology data sources (e.g., the BioModels Database) and researchers. Therefore, there is a need for all-in-one web-based solutions that support advance SBML functionalities such as uploading, editing, composing, visualizing, simulating, querying, and browsing computational models. We present the design and implementation of the Model Composition Tool (Interface) within the PathCase-SB (PathCase Systems Biology) web portal. The tool helps users compose systems biology models to facilitate the complex process of merging systems biology models. We also present three tools that support the model composition tool, namely, (1) Model Simulation Interface that generates a visual plot of the simulation according to user's input, (2) iModel Tool as a platform for users to upload their own models to compose, and (3) SimCom Tool that provides a side by side comparison of models being composed in the same pathway. Finally, we provide a web site that hosts BioModels Database models and a separate web site that hosts SBML Test Suite models. Model composition tool (and the other three tools) can be used with little or no knowledge of the SBML document structure. For this reason, students or anyone who wants to learn about systems biology will benefit from the described functionalities. SBML Test Suite models will be a nice starting point for beginners. And, for more advanced purposes, users will able to access and employ models of the BioModels Database as well.

  11. Modeling inputs to computer models used in risk assessment

    International Nuclear Information System (INIS)

    Iman, R.L.

    1987-01-01

    Computer models for various risk assessment applications are closely scrutinized both from the standpoint of questioning the correctness of the underlying mathematical model with respect to the process it is attempting to model and from the standpoint of verifying that the computer model correctly implements the underlying mathematical model. A process that receives less scrutiny, but is nonetheless of equal importance, concerns the individual and joint modeling of the inputs. This modeling effort clearly has a great impact on the credibility of results. Model characteristics are reviewed in this paper that have a direct bearing on the model input process and reasons are given for using probabilities-based modeling with the inputs. The authors also present ways to model distributions for individual inputs and multivariate input structures when dependence and other constraints may be present

  12. A Model of Trusted Measurement Model

    OpenAIRE

    Ma Zhili; Wang Zhihao; Dai Liang; Zhu Xiaoqin

    2017-01-01

    A model of Trusted Measurement supporting behavior measurement based on trusted connection architecture (TCA) with three entities and three levels is proposed, and a frame to illustrate the model is given. The model synthesizes three trusted measurement dimensions including trusted identity, trusted status and trusted behavior, satisfies the essential requirements of trusted measurement, and unified the TCA with three entities and three levels.

  13. A unification of RDE model and XCDM model

    International Nuclear Information System (INIS)

    Liao, Kai; Zhu, Zong-Hong

    2013-01-01

    In this Letter, we propose a new generalized Ricci dark energy (NGR) model to unify Ricci dark energy (RDE) and XCDM. Our model can distinguish between RDE and XCDM by introducing a parameter β called weight factor. When β=1, NGR model becomes the usual RDE model. The XCDM model is corresponding to β=0. Moreover, NGR model permits the situation where neither β=1 nor β=0. We then perform a statefinder analysis on NGR model to see how β effects the trajectory on the r–s plane. In order to know the value of β, we constrain NGR model with latest observations including type Ia supernovae (SNe Ia) from Union2 set (557 data), baryonic acoustic oscillation (BAO) observation from the spectroscopic Sloan Digital Sky Survey (SDSS) data release 7 (DR7) galaxy sample and cosmic microwave background (CMB) observation from the 7-year Wilkinson Microwave Anisotropy Probe (WMAP7) results. With Markov Chain Monte Carlo (MCMC) method, the constraint result is β=0.08 −0.21 +0.30 (1σ) −0.28 +0.43 (2σ), which manifests the observations prefer a XCDM universe rather than RDE model. It seems RDE model is ruled out in NGR scenario within 2σ regions. Furthermore, we compare it with some of successful cosmological models using AIC information criterion. NGR model seems to be a good choice for describing the universe.

  14. Downscaling GISS ModelE Boreal Summer Climate over Africa

    Science.gov (United States)

    Druyan, Leonard M.; Fulakeza, Matthew

    2015-01-01

    The study examines the perceived added value of downscaling atmosphere-ocean global climate model simulations over Africa and adjacent oceans by a nested regional climate model. NASA/Goddard Institute for Space Studies (GISS) coupled ModelE simulations for June- September 1998-2002 are used to form lateral boundary conditions for synchronous simulations by the GISS RM3 regional climate model. The ModelE computational grid spacing is 2deg latitude by 2.5deg longitude and the RM3 grid spacing is 0.44deg. ModelE precipitation climatology for June-September 1998-2002 is shown to be a good proxy for 30-year means so results based on the 5-year sample are presumed to be generally representative. Comparison with observational evidence shows several discrepancies in ModelE configuration of the boreal summer inter-tropical convergence zone (ITCZ). One glaring shortcoming is that ModelE simulations do not advance the West African rain band northward during the summer to represent monsoon precipitation onset over the Sahel. Results for 1998-2002 show that onset simulation is an important added value produced by downscaling with RM3. ModelE Eastern South Atlantic Ocean computed sea-surface temperatures (SST) are some 4 K warmer than reanalysis, contributing to large positive biases in overlying surface air temperatures (Tsfc). ModelE Tsfc are also too warm over most of Africa. RM3 downscaling somewhat mitigates the magnitude of Tsfc biases over the African continent, it eliminates the ModelE double ITCZ over the Atlantic and it produces more realistic orographic precipitation maxima. Parallel ModelE and RM3 simulations with observed SST forcing (in place of the predicted ocean) lower Tsfc errors but have mixed impacts on circulation and precipitation biases. Downscaling improvements of the meridional movement of the rain band over West Africa and the configuration of orographic precipitation maxima are realized irrespective of the SST biases.

  15. Essays on model uncertainty in financial models

    NARCIS (Netherlands)

    Li, Jing

    2018-01-01

    This dissertation studies model uncertainty, particularly in financial models. It consists of two empirical chapters and one theoretical chapter. The first empirical chapter (Chapter 2) classifies model uncertainty into parameter uncertainty and misspecification uncertainty. It investigates the

  16. Mixed models for predictive modeling in actuarial science

    NARCIS (Netherlands)

    Antonio, K.; Zhang, Y.

    2012-01-01

    We start with a general discussion of mixed (also called multilevel) models and continue with illustrating specific (actuarial) applications of this type of models. Technical details on (linear, generalized, non-linear) mixed models follow: model assumptions, specifications, estimation techniques

  17. ModelMate - A graphical user interface for model analysis

    Science.gov (United States)

    Banta, Edward R.

    2011-01-01

    ModelMate is a graphical user interface designed to facilitate use of model-analysis programs with models. This initial version of ModelMate supports one model-analysis program, UCODE_2005, and one model software program, MODFLOW-2005. ModelMate can be used to prepare input files for UCODE_2005, run UCODE_2005, and display analysis results. A link to the GW_Chart graphing program facilitates visual interpretation of results. ModelMate includes capabilities for organizing directories used with the parallel-processing capabilities of UCODE_2005 and for maintaining files in those directories to be identical to a set of files in a master directory. ModelMate can be used on its own or in conjunction with ModelMuse, a graphical user interface for MODFLOW-2005 and PHAST.

  18. Reactor core modeling practice: Operational requirements, model characteristics, and model validation

    International Nuclear Information System (INIS)

    Zerbino, H.

    1997-01-01

    The physical models implemented in power plant simulators have greatly increased in performance and complexity in recent years. This process has been enabled by the ever increasing computing power available at affordable prices. This paper describes this process from several angles: First the operational requirements which are more critical from the point of view of model performance, both for normal and off-normal operating conditions; A second section discusses core model characteristics in the light of the solutions implemented by Thomson Training and Simulation (TT and S) in several full-scope simulators recently built and delivered for Dutch, German, and French nuclear power plants; finally we consider the model validation procedures, which are of course an integral part of model development, and which are becoming more and more severe as performance expectations increase. As a conclusion, it may be asserted that in the core modeling field, as in other areas, the general improvement in the quality of simulation codes has resulted in a fairly rapid convergence towards mainstream engineering-grade calculations. This is remarkable performance in view of the stringent real-time requirements which the simulation codes must satisfy as well as the extremely wide range of operating conditions that they are called upon to cover with good accuracy. (author)

  19. Mineralogic Model (MM3.0) Analysis Model Report

    Energy Technology Data Exchange (ETDEWEB)

    C. Lum

    2002-02-12

    The purpose of this report is to document the Mineralogic Model (MM), Version 3.0 (MM3.0) with regard to data input, modeling methods, assumptions, uncertainties, limitations and validation of the model results, qualification status of the model, and the differences between Version 3.0 and previous versions. A three-dimensional (3-D) Mineralogic Model was developed for Yucca Mountain to support the analyses of hydrologic properties, radionuclide transport, mineral health hazards, repository performance, and repository design. Version 3.0 of the MM was developed from mineralogic data obtained from borehole samples. It consists of matrix mineral abundances as a function of x (easting), y (northing), and z (elevation), referenced to the stratigraphic framework defined in Version 3.1 of the Geologic Framework Model (GFM). The MM was developed specifically for incorporation into the 3-D Integrated Site Model (ISM). The MM enables project personnel to obtain calculated mineral abundances at any position, within any region, or within any stratigraphic unit in the model area. The significance of the MM for key aspects of site characterization and performance assessment is explained in the following subsections. This work was conducted in accordance with the Development Plan for the MM (CRWMS M&O 2000). The planning document for this Rev. 00, ICN 02 of this AMR is Technical Work Plan, TWP-NBS-GS-000003, Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01 (CRWMS M&O 2000). The purpose of this ICN is to record changes in the classification of input status by the resolution of the use of TBV software and data in this report. Constraints and limitations of the MM are discussed in the appropriate sections that follow. The MM is one component of the ISM, which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1

  20. Mineralogic Model (MM3.0) Analysis Model Report

    International Nuclear Information System (INIS)

    Lum, C.

    2002-01-01

    The purpose of this report is to document the Mineralogic Model (MM), Version 3.0 (MM3.0) with regard to data input, modeling methods, assumptions, uncertainties, limitations and validation of the model results, qualification status of the model, and the differences between Version 3.0 and previous versions. A three-dimensional (3-D) Mineralogic Model was developed for Yucca Mountain to support the analyses of hydrologic properties, radionuclide transport, mineral health hazards, repository performance, and repository design. Version 3.0 of the MM was developed from mineralogic data obtained from borehole samples. It consists of matrix mineral abundances as a function of x (easting), y (northing), and z (elevation), referenced to the stratigraphic framework defined in Version 3.1 of the Geologic Framework Model (GFM). The MM was developed specifically for incorporation into the 3-D Integrated Site Model (ISM). The MM enables project personnel to obtain calculated mineral abundances at any position, within any region, or within any stratigraphic unit in the model area. The significance of the MM for key aspects of site characterization and performance assessment is explained in the following subsections. This work was conducted in accordance with the Development Plan for the MM (CRWMS M and O 2000). The planning document for this Rev. 00, ICN 02 of this AMR is Technical Work Plan, TWP-NBS-GS-000003, Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01 (CRWMS M and O 2000). The purpose of this ICN is to record changes in the classification of input status by the resolution of the use of TBV software and data in this report. Constraints and limitations of the MM are discussed in the appropriate sections that follow. The MM is one component of the ISM, which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components

  1. ERM model analysis for adaptation to hydrological model errors

    Science.gov (United States)

    Baymani-Nezhad, M.; Han, D.

    2018-05-01

    Hydrological conditions are changed continuously and these phenomenons generate errors on flood forecasting models and will lead to get unrealistic results. Therefore, to overcome these difficulties, a concept called model updating is proposed in hydrological studies. Real-time model updating is one of the challenging processes in hydrological sciences and has not been entirely solved due to lack of knowledge about the future state of the catchment under study. Basically, in terms of flood forecasting process, errors propagated from the rainfall-runoff model are enumerated as the main source of uncertainty in the forecasting model. Hence, to dominate the exciting errors, several methods have been proposed by researchers to update the rainfall-runoff models such as parameter updating, model state updating, and correction on input data. The current study focuses on investigations about the ability of rainfall-runoff model parameters to cope with three types of existing errors, timing, shape and volume as the common errors in hydrological modelling. The new lumped model, the ERM model, has been selected for this study to evaluate its parameters for its use in model updating to cope with the stated errors. Investigation about ten events proves that the ERM model parameters can be updated to cope with the errors without the need to recalibrate the model.

  2. Model documentation report: Short-Term Hydroelectric Generation Model

    International Nuclear Information System (INIS)

    1993-08-01

    The purpose of this report is to define the objectives of the Short- Term Hydroelectric Generation Model (STHGM), describe its basic approach, and to provide details on the model structure. This report is intended as a reference document for model analysts, users, and the general public. Documentation of the model is in accordance with the Energy Information Administration's (AYE) legal obligation to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). The STHGM performs a short-term (18 to 27- month) forecast of hydroelectric generation in the United States using an autoregressive integrated moving average (UREMIA) time series model with precipitation as an explanatory variable. The model results are used as input for the short-term Energy Outlook

  3. Geochemistry Model Validation Report: External Accumulation Model

    International Nuclear Information System (INIS)

    Zarrabi, K.

    2001-01-01

    The purpose of this Analysis and Modeling Report (AMR) is to validate the External Accumulation Model that predicts accumulation of fissile materials in fractures and lithophysae in the rock beneath a degrading waste package (WP) in the potential monitored geologic repository at Yucca Mountain. (Lithophysae are voids in the rock having concentric shells of finely crystalline alkali feldspar, quartz, and other materials that were formed due to entrapped gas that later escaped, DOE 1998, p. A-25.) The intended use of this model is to estimate the quantities of external accumulation of fissile material for use in external criticality risk assessments for different types of degrading WPs: U.S. Department of Energy (DOE) Spent Nuclear Fuel (SNF) codisposed with High Level Waste (HLW) glass, commercial SNF, and Immobilized Plutonium Ceramic (Pu-ceramic) codisposed with HLW glass. The scope of the model validation is to (1) describe the model and the parameters used to develop the model, (2) provide rationale for selection of the parameters by comparisons with measured values, and (3) demonstrate that the parameters chosen are the most conservative selection for external criticality risk calculations. To demonstrate the applicability of the model, a Pu-ceramic WP is used as an example. The model begins with a source term from separately documented EQ6 calculations; where the source term is defined as the composition versus time of the water flowing out of a breached waste package (WP). Next, PHREEQC, is used to simulate the transport and interaction of the source term with the resident water and fractured tuff below the repository. In these simulations the primary mechanism for accumulation is mixing of the high pH, actinide-laden source term with resident water; thus lowering the pH values sufficiently for fissile minerals to become insoluble and precipitate. In the final section of the model, the outputs from PHREEQC, are processed to produce mass of accumulation

  4. Model uncertainty: Probabilities for models?

    International Nuclear Information System (INIS)

    Winkler, R.L.

    1994-01-01

    Like any other type of uncertainty, model uncertainty should be treated in terms of probabilities. The question is how to do this. The most commonly-used approach has a drawback related to the interpretation of the probabilities assigned to the models. If we step back and look at the big picture, asking what the appropriate focus of the model uncertainty question should be in the context of risk and decision analysis, we see that a different probabilistic approach makes more sense, although it raise some implementation questions. Current work that is underway to address these questions looks very promising

  5. Model evaluation methodology applicable to environmental assessment models

    International Nuclear Information System (INIS)

    Shaeffer, D.L.

    1979-08-01

    A model evaluation methodology is presented to provide a systematic framework within which the adequacy of environmental assessment models might be examined. The necessity for such a tool is motivated by the widespread use of models for predicting the environmental consequences of various human activities and by the reliance on these model predictions for deciding whether a particular activity requires the deployment of costly control measures. Consequently, the uncertainty associated with prediction must be established for the use of such models. The methodology presented here consists of six major tasks: model examination, algorithm examination, data evaluation, sensitivity analyses, validation studies, and code comparison. This methodology is presented in the form of a flowchart to show the logical interrelatedness of the various tasks. Emphasis has been placed on identifying those parameters which are most important in determining the predictive outputs of a model. Importance has been attached to the process of collecting quality data. A method has been developed for analyzing multiplicative chain models when the input parameters are statistically independent and lognormally distributed. Latin hypercube sampling has been offered as a promising candidate for doing sensitivity analyses. Several different ways of viewing the validity of a model have been presented. Criteria are presented for selecting models for environmental assessment purposes

  6. Galactic models

    International Nuclear Information System (INIS)

    Buchler, J.R.; Gottesman, S.T.; Hunter, J.H. Jr.

    1990-01-01

    Various papers on galactic models are presented. Individual topics addressed include: observations relating to galactic mass distributions; the structure of the Galaxy; mass distribution in spiral galaxies; rotation curves of spiral galaxies in clusters; grand design, multiple arm, and flocculent spiral galaxies; observations of barred spirals; ringed galaxies; elliptical galaxies; the modal approach to models of galaxies; self-consistent models of spiral galaxies; dynamical models of spiral galaxies; N-body models. Also discussed are: two-component models of galaxies; simulations of cloudy, gaseous galactic disks; numerical experiments on the stability of hot stellar systems; instabilities of slowly rotating galaxies; spiral structure as a recurrent instability; model gas flows in selected barred spiral galaxies; bar shapes and orbital stochasticity; three-dimensional models; polar ring galaxies; dynamical models of polar rings

  7. A Model-Model and Data-Model Comparison for the Early Eocene Hydrological Cycle

    Science.gov (United States)

    Carmichael, Matthew J.; Lunt, Daniel J.; Huber, Matthew; Heinemann, Malte; Kiehl, Jeffrey; LeGrande, Allegra; Loptson, Claire A.; Roberts, Chris D.; Sagoo, Navjit; Shields, Christine

    2016-01-01

    A range of proxy observations have recently provided constraints on how Earth's hydrological cycle responded to early Eocene climatic changes. However, comparisons of proxy data to general circulation model (GCM) simulated hydrology are limited and inter-model variability remains poorly characterised. In this work, we undertake an intercomparison of GCM-derived precipitation and P - E distributions within the extended EoMIP ensemble (Eocene Modelling Intercomparison Project; Lunt et al., 2012), which includes previously published early Eocene simulations performed using five GCMs differing in boundary conditions, model structure, and precipitation-relevant parameterisation schemes. We show that an intensified hydrological cycle, manifested in enhanced global precipitation and evaporation rates, is simulated for all Eocene simulations relative to the preindustrial conditions. This is primarily due to elevated atmospheric paleo-CO2, resulting in elevated temperatures, although the effects of differences in paleogeography and ice sheets are also important in some models. For a given CO2 level, globally averaged precipitation rates vary widely between models, largely arising from different simulated surface air temperatures. Models with a similar global sensitivity of precipitation rate to temperature (dP=dT ) display different regional precipitation responses for a given temperature change. Regions that are particularly sensitive to model choice include the South Pacific, tropical Africa, and the Peri-Tethys, which may represent targets for future proxy acquisition. A comparison of early and middle Eocene leaf-fossil-derived precipitation estimates with the GCM output illustrates that GCMs generally underestimate precipitation rates at high latitudes, although a possible seasonal bias of the proxies cannot be excluded. Models which warm these regions, either via elevated CO2 or by varying poorly constrained model parameter values, are most successful in simulating a

  8. The Bond Fluctuation Model and Other Lattice Models

    Science.gov (United States)

    Müller, Marcus

    Lattice models constitute a class of coarse-grained representations of polymeric materials. They have enjoyed a longstanding tradition for investigating the universal behavior of long chain molecules by computer simulations and enumeration techniques. A coarse-grained representation is often necessary to investigate properties on large time- and length scales. First, some justification for using lattice models will be given and the benefits and limitations will be discussed. Then, the bond fluctuation model by Carmesin and Kremer [1] is placed into the context of other lattice models and compared to continuum models. Some specific techniques for measuring the pressure in lattice models will be described. The bond fluctuation model has been employed in more than 100 simulation studies in the last decade and only few selected applications can be mentioned.

  9. A Distributed Snow Evolution Modeling System (SnowModel)

    Science.gov (United States)

    Liston, G. E.; Elder, K.

    2004-12-01

    A spatially distributed snow-evolution modeling system (SnowModel) has been specifically designed to be applicable over a wide range of snow landscapes, climates, and conditions. To reach this goal, SnowModel is composed of four sub-models: MicroMet defines the meteorological forcing conditions, EnBal calculates surface energy exchanges, SnowMass simulates snow depth and water-equivalent evolution, and SnowTran-3D accounts for snow redistribution by wind. While other distributed snow models exist, SnowModel is unique in that it includes a well-tested blowing-snow sub-model (SnowTran-3D) for application in windy arctic, alpine, and prairie environments where snowdrifts are common. These environments comprise 68% of the seasonally snow-covered Northern Hemisphere land surface. SnowModel also accounts for snow processes occurring in forested environments (e.g., canopy interception related processes). SnowModel is designed to simulate snow-related physical processes occurring at spatial scales of 5-m and greater, and temporal scales of 1-hour and greater. These include: accumulation from precipitation; wind redistribution and sublimation; loading, unloading, and sublimation within forest canopies; snow-density evolution; and snowpack ripening and melt. To enhance its wide applicability, SnowModel includes the physical calculations required to simulate snow evolution within each of the global snow classes defined by Sturm et al. (1995), e.g., tundra, taiga, alpine, prairie, maritime, and ephemeral snow covers. The three, 25-km by 25-km, Cold Land Processes Experiment (CLPX) mesoscale study areas (MSAs: Fraser, North Park, and Rabbit Ears) are used as SnowModel simulation examples to highlight model strengths, weaknesses, and features in forested, semi-forested, alpine, and shrubland environments.

  10. Event-based model diagnosis of rainfall-runoff model structures

    International Nuclear Information System (INIS)

    Stanzel, P.

    2012-01-01

    The objective of this research is a comparative evaluation of different rainfall-runoff model structures. Comparative model diagnostics facilitate the assessment of strengths and weaknesses of each model. The application of multiple models allows an analysis of simulation uncertainties arising from the selection of model structure, as compared with effects of uncertain parameters and precipitation input. Four different model structures, including conceptual and physically based approaches, are compared. In addition to runoff simulations, results for soil moisture and the runoff components of overland flow, interflow and base flow are analysed. Catchment runoff is simulated satisfactorily by all four model structures and shows only minor differences. Systematic deviations from runoff observations provide insight into model structural deficiencies. While physically based model structures capture some single runoff events better, they do not generally outperform conceptual model structures. Contributions to uncertainty in runoff simulations stemming from the choice of model structure show similar dimensions to those arising from parameter selection and the representation of precipitation input. Variations in precipitation mainly affect the general level and peaks of runoff, while different model structures lead to different simulated runoff dynamics. Large differences between the four analysed models are detected for simulations of soil moisture and, even more pronounced, runoff components. Soil moisture changes are more dynamical in the physically based model structures, which is in better agreement with observations. Streamflow contributions of overland flow are considerably lower in these models than in the more conceptual approaches. Observations of runoff components are rarely made and are not available in this study, but are shown to have high potential for an effective selection of appropriate model structures (author) [de

  11. Observation-Based Modeling for Model-Based Testing

    NARCIS (Netherlands)

    Kanstrén, T.; Piel, E.; Gross, H.G.

    2009-01-01

    One of the single most important reasons that modeling and modelbased testing are not yet common practice in industry is the perceived difficulty of making the models up to the level of detail and quality required for their automated processing. Models unleash their full potential only through

  12. Multi-Hypothesis Modelling Capabilities for Robust Data-Model Integration

    Science.gov (United States)

    Walker, A. P.; De Kauwe, M. G.; Lu, D.; Medlyn, B.; Norby, R. J.; Ricciuto, D. M.; Rogers, A.; Serbin, S.; Weston, D. J.; Ye, M.; Zaehle, S.

    2017-12-01

    Large uncertainty is often inherent in model predictions due to imperfect knowledge of how to describe the mechanistic processes (hypotheses) that a model is intended to represent. Yet this model hypothesis uncertainty (MHU) is often overlooked or informally evaluated, as methods to quantify and evaluate MHU are limited. MHU is increased as models become more complex because each additional processes added to a model comes with inherent MHU as well as parametric unceratinty. With the current trend of adding more processes to Earth System Models (ESMs), we are adding uncertainty, which can be quantified for parameters but not MHU. Model inter-comparison projects do allow for some consideration of hypothesis uncertainty but in an ad hoc and non-independent fashion. This has stymied efforts to evaluate ecosystem models against data and intepret the results mechanistically because it is not simple to interpret exactly why a model is producing the results it does and identify which model assumptions are key as they combine models of many sub-systems and processes, each of which may be conceptualised and represented mathematically in various ways. We present a novel modelling framework—the multi-assumption architecture and testbed (MAAT)—that automates the combination, generation, and execution of a model ensemble built with different representations of process. We will present the argument that multi-hypothesis modelling needs to be considered in conjunction with other capabilities (e.g. the Predictive Ecosystem Analyser; PecAn) and statistical methods (e.g. sensitivity anaylsis, data assimilation) to aid efforts in robust data model integration to enhance our predictive understanding of biological systems.

  13. Process models and model-data fusion in dendroecology

    Directory of Open Access Journals (Sweden)

    Joel eGuiot

    2014-08-01

    Full Text Available Dendrochronology (i.e. the study of annually dated tree-ring time series has proved to be a powerful technique to understand tree-growth. This paper intends to show the interest of using ecophysiological modeling not only to understand and predict tree-growth (dendroecology but also to reconstruct past climates (dendroclimatology. Process models have been used for several decades in dendroclimatology, but it is only recently that methods of model-data fusion have led to significant progress in modeling tree-growth as a function of climate and in reconstructing past climates. These model-data fusion (MDF methods, mainly based on the Bayesian paradigm, have been shown to be powerful for both model calibration and model inversion. After a rapid survey of tree-growth modeling, we illustrate MDF with examples based on series of Southern France Aleppo pines and Central France oaks. These examples show that if plants experienced CO2 fertilization, this would have a significant effect on tree-growth which in turn would bias the climate reconstructions. This bias could be extended to other environmental non-climatic factors directly or indirectly affecting annual ring formation and not taken into account in classical empirical models, which supports the use of more complex process-based models. Finally, we conclude by showing the interest of the data assimilation methods applied in climatology to produce climate re-analyses.

  14. `Models of' versus `Models for'. Toward an Agent-Based Conception of Modeling in the Science Classroom

    Science.gov (United States)

    Gouvea, Julia; Passmore, Cynthia

    2017-03-01

    The inclusion of the practice of "developing and using models" in the Framework for K-12 Science Education and in the Next Generation Science Standards provides an opportunity for educators to examine the role this practice plays in science and how it can be leveraged in a science classroom. Drawing on conceptions of models in the philosophy of science, we bring forward an agent-based account of models and discuss the implications of this view for enacting modeling in science classrooms. Models, according to this account, can only be understood with respect to the aims and intentions of a cognitive agent (models for), not solely in terms of how they represent phenomena in the world (models of). We present this contrast as a heuristic— models of versus models for—that can be used to help educators notice and interpret how models are positioned in standards, curriculum, and classrooms.

  15. Eclipse models

    International Nuclear Information System (INIS)

    Michel, F.C.

    1989-01-01

    Three existing eclipse models for the PSR 1957 + 20 pulsar are discussed in terms of their requirements and the information they yield about the pulsar wind: the interacting wind from a companion model, the magnetosphere model, and the occulting disk model. It is shown out that the wind model requires an MHD wind from the pulsar, with enough particles that the Poynting flux of the wind can be thermalized; in this model, a large flux of energetic radiation from the pulsar is required to accompany the wind and drive the wind off the companion. The magnetosphere model requires an EM wind, which is Poynting flux dominated; the advantage of this model over the wind model is that the plasma density inside the magnetosphere can be orders of magnitude larger than in a magnetospheric tail blown back by wind interaction. The occulting disk model also requires an EM wind so that the interaction would be pushed down onto the companion surface, minimizing direct interaction of the wind with the orbiting macroscopic particles

  16. Thermal unit availability modeling in a regional simulation model

    International Nuclear Information System (INIS)

    Yamayee, Z.A.; Port, J.; Robinett, W.

    1983-01-01

    The System Analysis Model (SAM) developed under the umbrella of PNUCC's System Analysis Committee is capable of simulating the operation of a given load/resource scenario. This model employs a Monte-Carlo simulation to incorporate uncertainties. Among uncertainties modeled is thermal unit availability both for energy simulation (seasonal) and capacity simulations (hourly). This paper presents the availability modeling in the capacity and energy models. The use of regional and national data in deriving the two availability models, the interaction between the two and modifications made to the capacity model in order to reflect regional practices is presented. A sample problem is presented to show the modification process. Results for modeling a nuclear unit using NERC-GADS is presented

  17. Using the Model Coupling Toolkit to couple earth system models

    Science.gov (United States)

    Warner, J.C.; Perlin, N.; Skyllingstad, E.D.

    2008-01-01

    Continued advances in computational resources are providing the opportunity to operate more sophisticated numerical models. Additionally, there is an increasing demand for multidisciplinary studies that include interactions between different physical processes. Therefore there is a strong desire to develop coupled modeling systems that utilize existing models and allow efficient data exchange and model control. The basic system would entail model "1" running on "M" processors and model "2" running on "N" processors, with efficient exchange of model fields at predetermined synchronization intervals. Here we demonstrate two coupled systems: the coupling of the ocean circulation model Regional Ocean Modeling System (ROMS) to the surface wave model Simulating WAves Nearshore (SWAN), and the coupling of ROMS to the atmospheric model Coupled Ocean Atmosphere Prediction System (COAMPS). Both coupled systems use the Model Coupling Toolkit (MCT) as a mechanism for operation control and inter-model distributed memory transfer of model variables. In this paper we describe requirements and other options for model coupling, explain the MCT library, ROMS, SWAN and COAMPS models, methods for grid decomposition and sparse matrix interpolation, and provide an example from each coupled system. Methods presented in this paper are clearly applicable for coupling of other types of models. ?? 2008 Elsevier Ltd. All rights reserved.

  18. Modeling Non-Gaussian Time Series with Nonparametric Bayesian Model.

    Science.gov (United States)

    Xu, Zhiguang; MacEachern, Steven; Xu, Xinyi

    2015-02-01

    We present a class of Bayesian copula models whose major components are the marginal (limiting) distribution of a stationary time series and the internal dynamics of the series. We argue that these are the two features with which an analyst is typically most familiar, and hence that these are natural components with which to work. For the marginal distribution, we use a nonparametric Bayesian prior distribution along with a cdf-inverse cdf transformation to obtain large support. For the internal dynamics, we rely on the traditionally successful techniques of normal-theory time series. Coupling the two components gives us a family of (Gaussian) copula transformed autoregressive models. The models provide coherent adjustments of time scales and are compatible with many extensions, including changes in volatility of the series. We describe basic properties of the models, show their ability to recover non-Gaussian marginal distributions, and use a GARCH modification of the basic model to analyze stock index return series. The models are found to provide better fit and improved short-range and long-range predictions than Gaussian competitors. The models are extensible to a large variety of fields, including continuous time models, spatial models, models for multiple series, models driven by external covariate streams, and non-stationary models.

  19. The Real and the Mathematical in Quantum Modeling: From Principles to Models and from Models to Principles

    Science.gov (United States)

    Plotnitsky, Arkady

    2017-06-01

    The history of mathematical modeling outside physics has been dominated by the use of classical mathematical models, C-models, primarily those of a probabilistic or statistical nature. More recently, however, quantum mathematical models, Q-models, based in the mathematical formalism of quantum theory have become more prominent in psychology, economics, and decision science. The use of Q-models in these fields remains controversial, in part because it is not entirely clear whether Q-models are necessary for dealing with the phenomena in question or whether C-models would still suffice. My aim, however, is not to assess the necessity of Q-models in these fields, but instead to reflect on what the possible applicability of Q-models may tell us about the corresponding phenomena there, vis-à-vis quantum phenomena in physics. In order to do so, I shall first discuss the key reasons for the use of Q-models in physics. In particular, I shall examine the fundamental principles that led to the development of quantum mechanics. Then I shall consider a possible role of similar principles in using Q-models outside physics. Psychology, economics, and decision science borrow already available Q-models from quantum theory, rather than derive them from their own internal principles, while quantum mechanics was derived from such principles, because there was no readily available mathematical model to handle quantum phenomena, although the mathematics ultimately used in quantum did in fact exist then. I shall argue, however, that the principle perspective on mathematical modeling outside physics might help us to understand better the role of Q-models in these fields and possibly to envision new models, conceptually analogous to but mathematically different from those of quantum theory, helpful or even necessary there or in physics itself. I shall suggest one possible type of such models, singularized probabilistic, SP, models, some of which are time-dependent, TDSP-models. The

  20. Optimisation of BPMN Business Models via Model Checking

    DEFF Research Database (Denmark)

    Herbert, Luke Thomas; Sharp, Robin

    2013-01-01

    We present a framework for the optimisation of business processes modelled in the business process modelling language BPMN, which builds upon earlier work, where we developed a model checking based method for the analysis of BPMN models. We define a structure for expressing optimisation goals...... for synthesized BPMN components, based on probabilistic computation tree logic and real-valued reward structures of the BPMN model, allowing for the specification of complex quantitative goals. We here present a simple algorithm, inspired by concepts from evolutionary algorithms, which iteratively generates...

  1. PENGGUNAAN THE ZMIJEWSKI MODEL, THE ALTMAN MODEL, DAN THE SPRINGATE MODEL SEBAGAI PREDIKTOR DELISTING

    Directory of Open Access Journals (Sweden)

    Mila Fatmawati

    2017-03-01

    Full Text Available The purpose of this study was to investigate empirical evidence that the Zmijewski model, the Altman model, andthe Springate models could be used as a predictor of delisting the company. Object of this study was to remove thelist of companies that trade shares (delisted in Indonesia Stock Exchange in 2003-2009. As a benchmark forcompanies delisted at the top used companies that were still listed on the Stock Exchange with the same numberand kind of business field. Comparison samples were taken randomly over the same period with the companydelisted. The method of analysis used logic regression. The results found that from the three delisting of predictormodels, only the Zmijewski models that could be used to predict the company delisted in the period of observation,while the Altman model and the Springate models could not be used as predictive models delisting. It is becauseThe Zmijewski model emphasized amounts of debt in predict delisting. The bigger the debt was, it would be moreaccurate in predicting as the company’s delisting. Meanwhile, the Altman model and the Springate modelemphasized more on profitability measures. The smaller the profitability was, the more precisely to predictcompany’s delisting. Condition of delisting the company that became object of observation company trends wasstill able to get profit, but it had a relative amount of debt.

  2. Process modelling on a canonical basis[Process modelling; Canonical modelling

    Energy Technology Data Exchange (ETDEWEB)

    Siepmann, Volker

    2006-12-20

    Based on an equation oriented solving strategy, this thesis investigates a new approach to process modelling. Homogeneous thermodynamic state functions represent consistent mathematical models of thermodynamic properties. Such state functions of solely extensive canonical state variables are the basis of this work, as they are natural objective functions in optimisation nodes to calculate thermodynamic equilibrium regarding phase-interaction and chemical reactions. Analytical state function derivatives are utilised within the solution process as well as interpreted as physical properties. By this approach, only a limited range of imaginable process constraints are considered, namely linear balance equations of state variables. A second-order update of source contributions to these balance equations is obtained by an additional constitutive equation system. These equations are general dependent on state variables and first-order sensitivities, and cover therefore practically all potential process constraints. Symbolic computation technology efficiently provides sparsity and derivative information of active equations to avoid performance problems regarding robustness and computational effort. A benefit of detaching the constitutive equation system is that the structure of the main equation system remains unaffected by these constraints, and a priori information allows to implement an efficient solving strategy and a concise error diagnosis. A tailor-made linear algebra library handles the sparse recursive block structures efficiently. The optimisation principle for single modules of thermodynamic equilibrium is extended to host entire process models. State variables of different modules interact through balance equations, representing material flows from one module to the other. To account for reusability and encapsulation of process module details, modular process modelling is supported by a recursive module structure. The second-order solving algorithm makes it

  3. Generalized latent variable modeling multilevel, longitudinal, and structural equation models

    CERN Document Server

    Skrondal, Anders; Rabe-Hesketh, Sophia

    2004-01-01

    This book unifies and extends latent variable models, including multilevel or generalized linear mixed models, longitudinal or panel models, item response or factor models, latent class or finite mixture models, and structural equation models.

  4. A Lagrangian mixing frequency model for transported PDF modeling

    Science.gov (United States)

    Turkeri, Hasret; Zhao, Xinyu

    2017-11-01

    In this study, a Lagrangian mixing frequency model is proposed for molecular mixing models within the framework of transported probability density function (PDF) methods. The model is based on the dissipations of mixture fraction and progress variables obtained from Lagrangian particles in PDF methods. The new model is proposed as a remedy to the difficulty in choosing the optimal model constant parameters when using conventional mixing frequency models. The model is implemented in combination with the Interaction by exchange with the mean (IEM) mixing model. The performance of the new model is examined by performing simulations of Sandia Flame D and the turbulent premixed flame from the Cambridge stratified flame series. The simulations are performed using the pdfFOAM solver which is a LES/PDF solver developed entirely in OpenFOAM. A 16-species reduced mechanism is used to represent methane/air combustion, and in situ adaptive tabulation is employed to accelerate the finite-rate chemistry calculations. The results are compared with experimental measurements as well as with the results obtained using conventional mixing frequency models. Dynamic mixing frequencies are predicted using the new model without solving additional transport equations, and good agreement with experimental data is observed.

  5. Modelling MIZ dynamics in a global model

    Science.gov (United States)

    Rynders, Stefanie; Aksenov, Yevgeny; Feltham, Daniel; Nurser, George; Naveira Garabato, Alberto

    2016-04-01

    Exposure of large, previously ice-covered areas of the Arctic Ocean to the wind and surface ocean waves results in the Arctic pack ice cover becoming more fragmented and mobile, with large regions of ice cover evolving into the Marginal Ice Zone (MIZ). The need for better climate predictions, along with growing economic activity in the Polar Oceans, necessitates climate and forecasting models that can simulate fragmented sea ice with a greater fidelity. Current models are not fully fit for the purpose, since they neither model surface ocean waves in the MIZ, nor account for the effect of floe fragmentation on drag, nor include sea ice rheology that represents both the now thinner pack ice and MIZ ice dynamics. All these processes affect the momentum transfer to the ocean. We present initial results from a global ocean model NEMO (Nucleus for European Modelling of the Ocean) coupled to the Los Alamos sea ice model CICE. The model setup implements a novel rheological formulation for sea ice dynamics, accounting for ice floe collisions, thus offering a seamless framework for pack ice and MIZ simulations. The effect of surface waves on ice motion is included through wave pressure and the turbulent kinetic energy of ice floes. In the multidecadal model integrations we examine MIZ and basin scale sea ice and oceanic responses to the changes in ice dynamics. We analyse model sensitivities and attribute them to key sea ice and ocean dynamical mechanisms. The results suggest that the effect of the new ice rheology is confined to the MIZ. However with the current increase in summer MIZ area, which is projected to continue and may become the dominant type of sea ice in the Arctic, we argue that the effects of the combined sea ice rheology will be noticeable in large areas of the Arctic Ocean, affecting sea ice and ocean. With this study we assert that to make more accurate sea ice predictions in the changing Arctic, models need to include MIZ dynamics and physics.

  6. Graphical Rasch models

    DEFF Research Database (Denmark)

    Kreiner, Svend; Christensen, Karl Bang

    Rasch models; Partial Credit models; Rating Scale models; Item bias; Differential item functioning; Local independence; Graphical models......Rasch models; Partial Credit models; Rating Scale models; Item bias; Differential item functioning; Local independence; Graphical models...

  7. Transforming Graphical System Models to Graphical Attack Models

    DEFF Research Database (Denmark)

    Ivanova, Marieta Georgieva; Probst, Christian W.; Hansen, Rene Rydhof

    2016-01-01

    Manually identifying possible attacks on an organisation is a complex undertaking; many different factors must be considered, and the resulting attack scenarios can be complex and hard to maintain as the organisation changes. System models provide a systematic representation of organisations...... approach to transforming graphical system models to graphical attack models in the form of attack trees. Based on an asset in the model, our transformations result in an attack tree that represents attacks by all possible actors in the model, after which the actor in question has obtained the asset....

  8. Integration of Simulink Models with Component-based Software Models

    DEFF Research Database (Denmark)

    Marian, Nicolae

    2008-01-01

    Model based development aims to facilitate the development of embedded control systems by emphasizing the separation of the design level from the implementation level. Model based design involves the use of multiple models that represent different views of a system, having different semantics...... of abstract system descriptions. Usually, in mechatronics systems, design proceeds by iterating model construction, model analysis, and model transformation. Constructing a MATLAB/Simulink model, a plant and controller behavior is simulated using graphical blocks to represent mathematical and logical...... constraints. COMDES (Component-based Design of Software for Distributed Embedded Systems) is such a component-based system framework developed by the software engineering group of Mads Clausen Institute for Product Innovation (MCI), University of Southern Denmark. Once specified, the software model has...

  9. Pavement Aging Model by Response Surface Modeling

    Directory of Open Access Journals (Sweden)

    Manzano-Ramírez A.

    2011-10-01

    Full Text Available In this work, surface course aging was modeled by Response Surface Methodology (RSM. The Marshall specimens were placed in a conventional oven for time and temperature conditions established on the basis of the environment factors of the region where the surface course is constructed by AC-20 from the Ing. Antonio M. Amor refinery. Volatilized material (VM, load resistance increment (ΔL and flow resistance increment (ΔF models were developed by the RSM. Cylindrical specimens with real aging were extracted from the surface course pilot to evaluate the error of the models. The VM model was adequate, in contrast (ΔL and (ΔF models were almost adequate with an error of 20 %, that was associated with the other environmental factors, which were not considered at the beginning of the research.

  10. Variable selection and model choice in geoadditive regression models.

    Science.gov (United States)

    Kneib, Thomas; Hothorn, Torsten; Tutz, Gerhard

    2009-06-01

    Model choice and variable selection are issues of major concern in practical regression analyses, arising in many biometric applications such as habitat suitability analyses, where the aim is to identify the influence of potentially many environmental conditions on certain species. We describe regression models for breeding bird communities that facilitate both model choice and variable selection, by a boosting algorithm that works within a class of geoadditive regression models comprising spatial effects, nonparametric effects of continuous covariates, interaction surfaces, and varying coefficients. The major modeling components are penalized splines and their bivariate tensor product extensions. All smooth model terms are represented as the sum of a parametric component and a smooth component with one degree of freedom to obtain a fair comparison between the model terms. A generic representation of the geoadditive model allows us to devise a general boosting algorithm that automatically performs model choice and variable selection.

  11. Model coupler for coupling of atmospheric, oceanic, and terrestrial models

    International Nuclear Information System (INIS)

    Nagai, Haruyasu; Kobayashi, Takuya; Tsuduki, Katsunori; Kim, Keyong-Ok

    2007-02-01

    A numerical simulation system SPEEDI-MP, which is applicable for various environmental studies, consists of dynamical models and material transport models for the atmospheric, terrestrial, and oceanic environments, meteorological and geographical databases for model inputs, and system utilities for file management, visualization, analysis, etc., using graphical user interfaces (GUIs). As a numerical simulation tool, a model coupling program (model coupler) has been developed. It controls parallel calculations of several models and data exchanges among them to realize the dynamical coupling of the models. It is applicable for any models with three-dimensional structured grid system, which is used by most environmental and hydrodynamic models. A coupled model system for water circulation has been constructed with atmosphere, ocean, wave, hydrology, and land-surface models using the model coupler. Performance tests of the coupled model system for water circulation were also carried out for the flood event at Saudi Arabia in January 2005 and the storm surge case by the hurricane KATRINA in August 2005. (author)

  12. ICRF modelling

    International Nuclear Information System (INIS)

    Phillips, C.K.

    1985-12-01

    This lecture provides a survey of the methods used to model fast magnetosonic wave coupling, propagation, and absorption in tokamaks. The validity and limitations of three distinct types of modelling codes, which will be contrasted, include discrete models which utilize ray tracing techniques, approximate continuous field models based on a parabolic approximation of the wave equation, and full field models derived using finite difference techniques. Inclusion of mode conversion effects in these models and modification of the minority distribution function will also be discussed. The lecture will conclude with a presentation of time-dependent global transport simulations of ICRF-heated tokamak discharges obtained in conjunction with the ICRF modelling codes. 52 refs., 15 figs

  13. Event Modeling

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2001-01-01

    The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... are dynamic and we present a modeling approach that can be used to model such dynamics.We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can...

  14. Degeneracy of time series models: The best model is not always the correct model

    International Nuclear Information System (INIS)

    Judd, Kevin; Nakamura, Tomomichi

    2006-01-01

    There are a number of good techniques for finding, in some sense, the best model of a deterministic system given a time series of observations. We examine a problem called model degeneracy, which has the consequence that even when a perfect model of a system exists, one does not find it using the best techniques currently available. The problem is illustrated using global polynomial models and the theory of Groebner bases

  15. On the shell model connection of the cluster model

    International Nuclear Information System (INIS)

    Cseh, J.; Levai, G.; Kato, K.

    2000-01-01

    Complete text of publication follows. The interrelation of basic nuclear structure models is a longstanding problem. The connection between the spherical shell model and the quadrupole collective model has been studied extensively, and symmetry considerations proved to be especially useful in this respect. A collective band was interpreted in the shell model language long ago as a set of states (of the valence nucleons) with a specific SU(3) symmetry. Furthermore, the energies of these rotational states are obtained to a good approximation as eigenvalues of an SU(3) dynamically symmetric shell model Hamiltonian. On the other hand the relation of the shell model and cluster model is less well explored. The connection of the harmonic oscillator (i.e. SU(3)) bases of the two approaches is known, but it was established only for the unrealistic harmonic oscillator interactions. Here we investigate the question: Can an SU(3) dynamically symmetric interaction provide a similar connection between the spherical shell model and the cluster model, like the one between the shell and collective models? In other words: whether or not the energy of the states of the cluster bands, defined by a specific SU(3) symmetries, can be obtained from a shell model Hamiltonian (with SU(3) dynamical symmetry). We carried out calculations within the framework of the semimicroscopic algebraic cluster model, in which not only the cluster model space is obtained from the full shell model space by an SU(3) symmetry-dictated truncation, but SU(3) dynamically symmetric interactions are also applied. Actually, Hamiltonians of this kind proved to be successful in describing the gross features of cluster states in a wide energy range. The novel feature of the present work is that we apply exclusively shell model interactions. The energies obtained from such a Hamiltonian for several bands of the ( 12 C, 14 C, 16 O, 20 Ne, 40 Ca) + α systems turn out to be in good agreement with the experimental

  16. Approximating chiral quark models with linear σ-models

    International Nuclear Information System (INIS)

    Broniowski, Wojciech; Golli, Bojan

    2003-01-01

    We study the approximation of chiral quark models with simpler models, obtained via gradient expansion. The resulting Lagrangian of the type of the linear σ-model contains, at the lowest level of the gradient-expanded meson action, an additional term of the form ((1)/(2))A(σ∂ μ σ+π∂ μ π) 2 . We investigate the dynamical consequences of this term and its relevance to the phenomenology of the soliton models of the nucleon. It is found that the inclusion of the new term allows for a more efficient approximation of the underlying quark theory, especially in those cases where dynamics allows for a large deviation of the chiral fields from the chiral circle, such as in quark models with non-local regulators. This is of practical importance, since the σ-models with valence quarks only are technically much easier to treat and simpler to solve than the quark models with the full-fledged Dirac sea

  17. Multivariate statistical modelling based on generalized linear models

    CERN Document Server

    Fahrmeir, Ludwig

    1994-01-01

    This book is concerned with the use of generalized linear models for univariate and multivariate regression analysis. Its emphasis is to provide a detailed introductory survey of the subject based on the analysis of real data drawn from a variety of subjects including the biological sciences, economics, and the social sciences. Where possible, technical details and proofs are deferred to an appendix in order to provide an accessible account for non-experts. Topics covered include: models for multi-categorical responses, model checking, time series and longitudinal data, random effects models, and state-space models. Throughout, the authors have taken great pains to discuss the underlying theoretical ideas in ways that relate well to the data at hand. As a result, numerous researchers whose work relies on the use of these models will find this an invaluable account to have on their desks. "The basic aim of the authors is to bring together and review a large part of recent advances in statistical modelling of m...

  18. Modeling arson - An exercise in qualitative model building

    Science.gov (United States)

    Heineke, J. M.

    1975-01-01

    A detailed example is given of the role of von Neumann and Morgenstern's 1944 'expected utility theorem' (in the theory of games and economic behavior) in qualitative model building. Specifically, an arsonist's decision as to the amount of time to allocate to arson and related activities is modeled, and the responsiveness of this time allocation to changes in various policy parameters is examined. Both the activity modeled and the method of presentation are intended to provide an introduction to the scope and power of the expected utility theorem in modeling situations of 'choice under uncertainty'. The robustness of such a model is shown to vary inversely with the number of preference restrictions used in the analysis. The fewer the restrictions, the wider is the class of agents to which the model is applicable, and accordingly more confidence is put in the derived results. A methodological discussion on modeling human behavior is included.

  19. Air Quality Dispersion Modeling - Alternative Models

    Science.gov (United States)

    Models, not listed in Appendix W, that can be used in regulatory applications with case-by-case justification to the Reviewing Authority as noted in Section 3.2, Use of Alternative Models, in Appendix W.

  20. On the shell-model-connection of the cluster model

    International Nuclear Information System (INIS)

    Cseh, J.

    2000-01-01

    Complete text of publication follows. The interrelation of basic nuclear structure models is a longstanding problem. The connection between the spherical shell model and the quadrupole collective model has been studied extensively, and symmetry considerations proved to be especially useful in this respect. A collective band was interpreted in the shell model language long ago [1] as a set of states (of the valence nucleons) with a specific SU(3) symmetry. Furthermore, the energies of these rotational states are obtained to a good approximation as eigenvalues of an SU(3) dynamically symmetric shell model Hamiltonian. On the other hand the relation of the shell model and cluster model is less well explored. The connection of the harmonic oscillator (i.e. SU(3)) bases of the two approaches is known [2] but it was established only for the unrealistic harmonic oscillator interactions. Here we investigate the question: Can an SU(3) dynamically symmetric interaction provide a similar connection between the spherical shell model and the cluster model, like the one between the shell and collective models? In other words: whether or not the energy of the states of the cluster bands, defined by a specific SU(3) symmetries, can be obtained from a shell model Hamiltonian (with SU(3) dynamical symmetry). We carried out calculations within the framework of the semimicroscopic algebraic cluster model [3,4] in order to find an answer to this question, which seems to be affirmative. In particular, the energies obtained from such a Hamiltonian for several bands of the ( 12 C, 14 C, 16 O, 20 Ne, 40 Ca) + α systems turn out to be in good agreement with the experimental values. The present results show that the simple and transparent SU(3) connection between the spherical shell model and the cluster model is valid not only for the harmonic oscillator interactions, but for much more general (SU(3) dynamically symmetric) Hamiltonians as well, which result in realistic energy spectra. Via

  1. Wind tunnel modeling of roadways: Comparison with mathematical models

    International Nuclear Information System (INIS)

    Heidorn, K.; Davies, A.E.; Murphy, M.C.

    1991-01-01

    The assessment of air quality impacts from roadways is a major concern to urban planners. In order to assess future road and building configurations, a number of techniques have been developed including mathematical models, which simulate traffic emissions and atmospheric dispersion through a series of mathematical relationships and physical models. The latter models simulate emissions and dispersion through scaling of these processes in a wind tunnel. Two roadway mathematical models, HIWAY-2 and CALINE-4, were applied to a proposed development in a large urban area. Physical modeling procedures developed by Rowan Williams Davies and Irwin Inc. (RWDI) in the form of line source simulators were also applied, and the resulting carbon monoxide concentrations were compared. The results indicated a factor of two agreement between the mathematical and physical models. The physical model, however, reacted to change in building massing and configuration. The mathematical models did not, since no provision for such changes was included in the mathematical models. In general, the RWDI model resulted in higher concentrations than either HIWAY-2 or CALINE-4. Where there was underprediction, it was often due to shielding of the receptor by surrounding buildings. Comparison of these three models with the CALTRANS Tracer Dispersion Experiment showed good results although concentrations were consistently underpredicted

  2. Analysis of deregulation models; Denryoku shijo jiyuka model no bunseki

    Energy Technology Data Exchange (ETDEWEB)

    Yajima, M. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1996-04-01

    Trends toward power market deregulation were investigated in Japan and 16 other countries, and various deregulation models were examined and evaluated for their merits and demerits. There are four basic models, that is, franchise bidding model, competitive bidding in power generation model, wholesale wheeling or retail wheeling model, and mandatory pool or voluntary pool model. Power market deregulation has been a global tendency since the second half of the 1970s, with various models adopted by different countries. Out of the above-said models, it is the retail wheeling model and pool models (open access models) that allow the final customer to select power suppliers, and the number of countries adopting these models is increasing. The said models are characterized in that the disintegration of the vertical transmission-distribution integration (separation of distribution service and retail supply service) and the liberation of the retail market are simultaneously accomplished. The pool models, in particular, are enjoying favor because conditions for fair competition have already been prepared and because it is believed high in efficiency. In Japan and France, where importance is attached to atomic power generation, the competitive bidding model is adopted as a means to harmonize the introduction of competition into the source development and power generation sectors. 7 refs., 4 tabs.

  3. Modelling Overview

    DEFF Research Database (Denmark)

    Larsen, Lars Bjørn; Vesterager, Johan

    This report provides an overview of the existing models of global manufacturing, describes the required modelling views and associated methods and identifies tools, which can provide support for this modelling activity.The model adopted for global manufacturing is that of an extended enterprise s...

  4. Statistical Model Checking of Rich Models and Properties

    DEFF Research Database (Denmark)

    Poulsen, Danny Bøgsted

    in undecidability issues for the traditional model checking approaches. Statistical model checking has proven itself a valuable supplement to model checking and this thesis is concerned with extending this software validation technique to stochastic hybrid systems. The thesis consists of two parts: the first part...... motivates why existing model checking technology should be supplemented by new techniques. It also contains a brief introduction to probability theory and concepts covered by the six papers making up the second part. The first two papers are concerned with developing online monitoring techniques...... systems. The fifth paper shows how stochastic hybrid automata are useful for modelling biological systems and the final paper is concerned with showing how statistical model checking is efficiently distributed. In parallel with developing the theory contained in the papers, a substantial part of this work...

  5. Geochemistry Model Validation Report: Material Degradation and Release Model

    Energy Technology Data Exchange (ETDEWEB)

    H. Stockman

    2001-09-28

    The purpose of this Analysis and Modeling Report (AMR) is to validate the Material Degradation and Release (MDR) model that predicts degradation and release of radionuclides from a degrading waste package (WP) in the potential monitored geologic repository at Yucca Mountain. This AMR is prepared according to ''Technical Work Plan for: Waste Package Design Description for LA'' (Ref. 17). The intended use of the MDR model is to estimate the long-term geochemical behavior of waste packages (WPs) containing U. S . Department of Energy (DOE) Spent Nuclear Fuel (SNF) codisposed with High Level Waste (HLW) glass, commercial SNF, and Immobilized Plutonium Ceramic (Pu-ceramic) codisposed with HLW glass. The model is intended to predict (1) the extent to which criticality control material, such as gadolinium (Gd), will remain in the WP after corrosion of the initial WP, (2) the extent to which fissile Pu and uranium (U) will be carried out of the degraded WP by infiltrating water, and (3) the chemical composition and amounts of minerals and other solids left in the WP. The results of the model are intended for use in criticality calculations. The scope of the model validation report is to (1) describe the MDR model, and (2) compare the modeling results with experimental studies. A test case based on a degrading Pu-ceramic WP is provided to help explain the model. This model does not directly feed the assessment of system performance. The output from this model is used by several other models, such as the configuration generator, criticality, and criticality consequence models, prior to the evaluation of system performance. This document has been prepared according to AP-3.10Q, ''Analyses and Models'' (Ref. 2), and prepared in accordance with the technical work plan (Ref. 17).

  6. Geochemistry Model Validation Report: Material Degradation and Release Model

    International Nuclear Information System (INIS)

    Stockman, H.

    2001-01-01

    The purpose of this Analysis and Modeling Report (AMR) is to validate the Material Degradation and Release (MDR) model that predicts degradation and release of radionuclides from a degrading waste package (WP) in the potential monitored geologic repository at Yucca Mountain. This AMR is prepared according to ''Technical Work Plan for: Waste Package Design Description for LA'' (Ref. 17). The intended use of the MDR model is to estimate the long-term geochemical behavior of waste packages (WPs) containing U. S . Department of Energy (DOE) Spent Nuclear Fuel (SNF) codisposed with High Level Waste (HLW) glass, commercial SNF, and Immobilized Plutonium Ceramic (Pu-ceramic) codisposed with HLW glass. The model is intended to predict (1) the extent to which criticality control material, such as gadolinium (Gd), will remain in the WP after corrosion of the initial WP, (2) the extent to which fissile Pu and uranium (U) will be carried out of the degraded WP by infiltrating water, and (3) the chemical composition and amounts of minerals and other solids left in the WP. The results of the model are intended for use in criticality calculations. The scope of the model validation report is to (1) describe the MDR model, and (2) compare the modeling results with experimental studies. A test case based on a degrading Pu-ceramic WP is provided to help explain the model. This model does not directly feed the assessment of system performance. The output from this model is used by several other models, such as the configuration generator, criticality, and criticality consequence models, prior to the evaluation of system performance. This document has been prepared according to AP-3.10Q, ''Analyses and Models'' (Ref. 2), and prepared in accordance with the technical work plan (Ref. 17)

  7. Assessing physical models used in nuclear aerosol transport models

    International Nuclear Information System (INIS)

    McDonald, B.H.

    1987-01-01

    Computer codes used to predict the behaviour of aerosols in water-cooled reactor containment buildings after severe accidents contain a variety of physical models. Special models are in place for describing agglomeration processes where small aerosol particles combine to form larger ones. Other models are used to calculate the rates at which aerosol particles are deposited on building structures. Condensation of steam on aerosol particles is currently a very active area in aerosol modelling. In this paper, the physical models incorporated in the current available international codes for all of these processes are reviewed and documented. There is considerable variation in models used in different codes, and some uncertainties exist as to which models are superior. 28 refs

  8. Particle Tracking Model (PTM) with Coastal Modeling System (CMS)

    Science.gov (United States)

    2015-11-04

    Coastal Inlets Research Program Particle Tracking Model (PTM) with Coastal Modeling System ( CMS ) The Particle Tracking Model (PTM) is a Lagrangian...currents and waves. The Coastal Inlets Research Program (CIRP) supports the PTM with the Coastal Modeling System ( CMS ), which provides coupled wave...and current forcing for PTM simulations. CMS -PTM is implemented in the Surface-water Modeling System, a GUI environment for input development

  9. A BRDF statistical model applying to space target materials modeling

    Science.gov (United States)

    Liu, Chenghao; Li, Zhi; Xu, Can; Tian, Qichen

    2017-10-01

    In order to solve the problem of poor effect in modeling the large density BRDF measured data with five-parameter semi-empirical model, a refined statistical model of BRDF which is suitable for multi-class space target material modeling were proposed. The refined model improved the Torrance-Sparrow model while having the modeling advantages of five-parameter model. Compared with the existing empirical model, the model contains six simple parameters, which can approximate the roughness distribution of the material surface, can approximate the intensity of the Fresnel reflectance phenomenon and the attenuation of the reflected light's brightness with the azimuth angle changes. The model is able to achieve parameter inversion quickly with no extra loss of accuracy. The genetic algorithm was used to invert the parameters of 11 different samples in the space target commonly used materials, and the fitting errors of all materials were below 6%, which were much lower than those of five-parameter model. The effect of the refined model is verified by comparing the fitting results of the three samples at different incident zenith angles in 0° azimuth angle. Finally, the three-dimensional modeling visualizations of these samples in the upper hemisphere space was given, in which the strength of the optical scattering of different materials could be clearly shown. It proved the good describing ability of the refined model at the material characterization as well.

  10. EIA model documentation: Petroleum market model of the national energy modeling system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-28

    The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. Documentation of the model is in accordance with EIA`s legal obligation to provide adequate documentation in support of its models. The PMM models petroleum refining activities, the marketing of petroleum products to consumption regions, the production of natural gas liquids in gas processing plants, and domestic methanol production. The PMM projects petroleum product prices and sources of supply for meeting petroleum product demand. The sources of supply include crude oil, both domestic and imported; other inputs including alcohols and ethers; natural gas plant liquids production; petroleum product imports; and refinery processing gain. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption. Product prices are estimated at the Census division level and much of the refining activity information is at the Petroleum Administration for Defense (PAD) District level.

  11. EIA model documentation: Petroleum market model of the national energy modeling system

    International Nuclear Information System (INIS)

    1995-01-01

    The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. Documentation of the model is in accordance with EIA's legal obligation to provide adequate documentation in support of its models. The PMM models petroleum refining activities, the marketing of petroleum products to consumption regions, the production of natural gas liquids in gas processing plants, and domestic methanol production. The PMM projects petroleum product prices and sources of supply for meeting petroleum product demand. The sources of supply include crude oil, both domestic and imported; other inputs including alcohols and ethers; natural gas plant liquids production; petroleum product imports; and refinery processing gain. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption. Product prices are estimated at the Census division level and much of the refining activity information is at the Petroleum Administration for Defense (PAD) District level

  12. Towards policy relevant environmental modeling: contextual validity and pragmatic models

    Science.gov (United States)

    Miles, Scott B.

    2000-01-01

    "What makes for a good model?" In various forms, this question is a question that, undoubtedly, many people, businesses, and institutions ponder with regards to their particular domain of modeling. One particular domain that is wrestling with this question is the multidisciplinary field of environmental modeling. Examples of environmental models range from models of contaminated ground water flow to the economic impact of natural disasters, such as earthquakes. One of the distinguishing claims of the field is the relevancy of environmental modeling to policy and environment-related decision-making in general. A pervasive view by both scientists and decision-makers is that a "good" model is one that is an accurate predictor. Thus, determining whether a model is "accurate" or "correct" is done by comparing model output to empirical observations. The expected outcome of this process, usually referred to as "validation" or "ground truthing," is a stamp on the model in question of "valid" or "not valid" that serves to indicate whether or not the model will be reliable before it is put into service in a decision-making context. In this paper, I begin by elaborating on the prevailing view of model validation and why this view must change. Drawing from concepts coming out of the studies of science and technology, I go on to propose a contextual view of validity that can overcome the problems associated with "ground truthing" models as an indicator of model goodness. The problem of how we talk about and determine model validity has much to do about how we perceive the utility of environmental models. In the remainder of the paper, I argue that we should adopt ideas of pragmatism in judging what makes for a good model and, in turn, developing good models. From such a perspective of model goodness, good environmental models should facilitate communication, convey—not bury or "eliminate"—uncertainties, and, thus, afford the active building of consensus decisions, instead

  13. Stochastic biomathematical models with applications to neuronal modeling

    CERN Document Server

    Batzel, Jerry; Ditlevsen, Susanne

    2013-01-01

    Stochastic biomathematical models are becoming increasingly important as new light is shed on the role of noise in living systems. In certain biological systems, stochastic effects may even enhance a signal, thus providing a biological motivation for the noise observed in living systems. Recent advances in stochastic analysis and increasing computing power facilitate the analysis of more biophysically realistic models, and this book provides researchers in computational neuroscience and stochastic systems with an overview of recent developments. Key concepts are developed in chapters written by experts in their respective fields. Topics include: one-dimensional homogeneous diffusions and their boundary behavior, large deviation theory and its application in stochastic neurobiological models, a review of mathematical methods for stochastic neuronal integrate-and-fire models, stochastic partial differential equation models in neurobiology, and stochastic modeling of spreading cortical depression.

  14. Modelling of an homogeneous equilibrium mixture model

    International Nuclear Information System (INIS)

    Bernard-Champmartin, A.; Poujade, O.; Mathiaud, J.; Mathiaud, J.; Ghidaglia, J.M.

    2014-01-01

    We present here a model for two phase flows which is simpler than the 6-equations models (with two densities, two velocities, two temperatures) but more accurate than the standard mixture models with 4 equations (with two densities, one velocity and one temperature). We are interested in the case when the two-phases have been interacting long enough for the drag force to be small but still not negligible. The so-called Homogeneous Equilibrium Mixture Model (HEM) that we present is dealing with both mixture and relative quantities, allowing in particular to follow both a mixture velocity and a relative velocity. This relative velocity is not tracked by a conservation law but by a closure law (drift relation), whose expression is related to the drag force terms of the two-phase flow. After the derivation of the model, a stability analysis and numerical experiments are presented. (authors)

  15. Temperature-based modeling of reference evapotranspiration using several artificial intelligence models: application of different modeling scenarios

    Science.gov (United States)

    Sanikhani, Hadi; Kisi, Ozgur; Maroufpoor, Eisa; Yaseen, Zaher Mundher

    2018-02-01

    The establishment of an accurate computational model for predicting reference evapotranspiration (ET0) process is highly essential for several agricultural and hydrological applications, especially for the rural water resource systems, water use allocations, utilization and demand assessments, and the management of irrigation systems. In this research, six artificial intelligence (AI) models were investigated for modeling ET0 using a small number of climatic data generated from the minimum and maximum temperatures of the air and extraterrestrial radiation. The investigated models were multilayer perceptron (MLP), generalized regression neural networks (GRNN), radial basis neural networks (RBNN), integrated adaptive neuro-fuzzy inference systems with grid partitioning and subtractive clustering (ANFIS-GP and ANFIS-SC), and gene expression programming (GEP). The implemented monthly time scale data set was collected at the Antalya and Isparta stations which are located in the Mediterranean Region of Turkey. The Hargreaves-Samani (HS) equation and its calibrated version (CHS) were used to perform a verification analysis of the established AI models. The accuracy of validation was focused on multiple quantitative metrics, including root mean squared error (RMSE), mean absolute error (MAE), correlation coefficient (R 2), coefficient of residual mass (CRM), and Nash-Sutcliffe efficiency coefficient (NS). The results of the conducted models were highly practical and reliable for the investigated case studies. At the Antalya station, the performance of the GEP and GRNN models was better than the other investigated models, while the performance of the RBNN and ANFIS-SC models was best compared to the other models at the Isparta station. Except for the MLP model, all the other investigated models presented a better performance accuracy compared to the HS and CHS empirical models when applied in a cross-station scenario. A cross-station scenario examination implies the

  16. Deformed baryons: constituent quark model vs. bag model

    International Nuclear Information System (INIS)

    Iwamura, Y.; Nogami, Y.

    1985-01-01

    Recently Bhaduri et al. developed a nonrelativistic constituent quark model for deformed baryons. In that model the quarks move in a deformable mean field, and the deformation parameters are determined by minimizing the quark energy subject to the constraint of volume conservation. This constraint is an ad hoc assumption. It is shown that, starting with a bag model, a model similar to that of Bhaduri et al. can be constructed. The deformation parameters are determined by the pressure balance on the bag surface. There is, however, a distinct difference between the two models with respect to the state dependence of the ''volume''. Implications of this difference are discussed

  17. Business Model Innovation: How Iconic Business Models Emerge

    OpenAIRE

    Mikhalkina, T.; Cabantous, L.

    2015-01-01

    Despite ample research on the topic of business model innovation, little is known about the cognitive processes whereby some innovative business models gain the status of iconic representations of particular types of firms. This study addresses the question: How do iconic business models emerge? In other words: How do innovative business models become prototypical exemplars for new categories of firms? We focus on the case of Airbnb, and analyze how six mainstream business media publications ...

  18. ECONOMIC MODELING STOCKS CONTROL SYSTEM: SIMULATION MODEL

    OpenAIRE

    Климак, М.С.; Войтко, С.В.

    2016-01-01

    Considered theoretical and applied aspects of the development of simulation models to predictthe optimal development and production systems that create tangible products andservices. It isproved that theprocessof inventory control needs of economicandmathematical modeling in viewof thecomplexity of theoretical studies. A simulation model of stocks control that allows make managementdecisions with production logistics

  19. Bayesian Model Averaging of Artificial Intelligence Models for Hydraulic Conductivity Estimation

    Science.gov (United States)

    Nadiri, A.; Chitsazan, N.; Tsai, F. T.; Asghari Moghaddam, A.

    2012-12-01

    This research presents a Bayesian artificial intelligence model averaging (BAIMA) method that incorporates multiple artificial intelligence (AI) models to estimate hydraulic conductivity and evaluate estimation uncertainties. Uncertainty in the AI model outputs stems from error in model input as well as non-uniqueness in selecting different AI methods. Using one single AI model tends to bias the estimation and underestimate uncertainty. BAIMA employs Bayesian model averaging (BMA) technique to address the issue of using one single AI model for estimation. BAIMA estimates hydraulic conductivity by averaging the outputs of AI models according to their model weights. In this study, the model weights were determined using the Bayesian information criterion (BIC) that follows the parsimony principle. BAIMA calculates the within-model variances to account for uncertainty propagation from input data to AI model output. Between-model variances are evaluated to account for uncertainty due to model non-uniqueness. We employed Takagi-Sugeno fuzzy logic (TS-FL), artificial neural network (ANN) and neurofuzzy (NF) to estimate hydraulic conductivity for the Tasuj plain aquifer, Iran. BAIMA combined three AI models and produced better fitting than individual models. While NF was expected to be the best AI model owing to its utilization of both TS-FL and ANN models, the NF model is nearly discarded by the parsimony principle. The TS-FL model and the ANN model showed equal importance although their hydraulic conductivity estimates were quite different. This resulted in significant between-model variances that are normally ignored by using one AI model.

  20. Climate simulations for 1880-2003 with GISS modelE

    International Nuclear Information System (INIS)

    Hansen, J.; Lacis, A.; Miller, R.; Schmidt, G.A.; Russell, G.; Canuto, V.; Del Genio, A.; Hall, T.; Hansen, J.; Sato, M.; Kharecha, P.; Nazarenko, L.; Aleinov, I.; Bauer, S.; Chandler, M.; Faluvegi, G.; Jonas, J.; Ruedy, R.; Lo, K.; Cheng, Y.; Lacis, A.; Schmidt, G.A.; Del Genio, A.; Miller, R.; Cairns, B.; Hall, T.; Baum, E.; Cohen, A.; Fleming, E.; Jackman, C.; Friend, A.; Kelley, M.

    2007-01-01

    We carry out climate simulations for 1880-2003 with GISS modelE driven by ten measured or estimated climate forcing. An ensemble of climate model runs is carried out for each forcing acting individually and for all forcing mechanisms acting together. We compare side-by-side simulated climate change for each forcing, all forcing, observations, unforced variability among model ensemble members, and, if available, observed variability. Discrepancies between observations and simulations with all forcing are due to model deficiencies, inaccurate or incomplete forcing, and imperfect observations. Although there are notable discrepancies between model and observations, the fidelity is sufficient to encourage use of the model for simulations of future climate change. By using a fixed well-documented model and accurately defining the 1880-2003 forcing, we aim to provide a benchmark against which the effect of improvements in the model, climate forcing, and observations can be tested. Principal model deficiencies include unrealistic weak tropical El Nino-like variability and a poor distribution of sea ice, with too much sea ice in the Northern Hemisphere and too little in the Southern Hemisphere. Greatest uncertainties in the forcing are the temporal and spatial variations of anthropogenic aerosols and their indirect effects on clouds. (authors)

  1. ModelMage: a tool for automatic model generation, selection and management.

    Science.gov (United States)

    Flöttmann, Max; Schaber, Jörg; Hoops, Stephan; Klipp, Edda; Mendes, Pedro

    2008-01-01

    Mathematical modeling of biological systems usually involves implementing, simulating, and discriminating several candidate models that represent alternative hypotheses. Generating and managing these candidate models is a tedious and difficult task and can easily lead to errors. ModelMage is a tool that facilitates management of candidate models. It is designed for the easy and rapid development, generation, simulation, and discrimination of candidate models. The main idea of the program is to automatically create a defined set of model alternatives from a single master model. The user provides only one SBML-model and a set of directives from which the candidate models are created by leaving out species, modifiers or reactions. After generating models the software can automatically fit all these models to the data and provides a ranking for model selection, in case data is available. In contrast to other model generation programs, ModelMage aims at generating only a limited set of models that the user can precisely define. ModelMage uses COPASI as a simulation and optimization engine. Thus, all simulation and optimization features of COPASI are readily incorporated. ModelMage can be downloaded from http://sysbio.molgen.mpg.de/modelmage and is distributed as free software.

  2. Modelling binary data

    CERN Document Server

    Collett, David

    2002-01-01

    INTRODUCTION Some Examples The Scope of this Book Use of Statistical Software STATISTICAL INFERENCE FOR BINARY DATA The Binomial Distribution Inference about the Success Probability Comparison of Two Proportions Comparison of Two or More Proportions MODELS FOR BINARY AND BINOMIAL DATA Statistical Modelling Linear Models Methods of Estimation Fitting Linear Models to Binomial Data Models for Binomial Response Data The Linear Logistic Model Fitting the Linear Logistic Model to Binomial Data Goodness of Fit of a Linear Logistic Model Comparing Linear Logistic Models Linear Trend in Proportions Comparing Stimulus-Response Relationships Non-Convergence and Overfitting Some other Goodness of Fit Statistics Strategy for Model Selection Predicting a Binary Response Probability BIOASSAY AND SOME OTHER APPLICATIONS The Tolerance Distribution Estimating an Effective Dose Relative Potency Natural Response Non-Linear Logistic Regression Models Applications of the Complementary Log-Log Model MODEL CHECKING Definition of Re...

  3. Model theory

    CERN Document Server

    Chang, CC

    2012-01-01

    Model theory deals with a branch of mathematical logic showing connections between a formal language and its interpretations or models. This is the first and most successful textbook in logical model theory. Extensively updated and corrected in 1990 to accommodate developments in model theoretic methods - including classification theory and nonstandard analysis - the third edition added entirely new sections, exercises, and references. Each chapter introduces an individual method and discusses specific applications. Basic methods of constructing models include constants, elementary chains, Sko

  4. Multistate Model Builder (MSMB): a flexible editor for compact biochemical models.

    Science.gov (United States)

    Palmisano, Alida; Hoops, Stefan; Watson, Layne T; Jones, Thomas C; Tyson, John J; Shaffer, Clifford A

    2014-04-04

    Building models of molecular regulatory networks is challenging not just because of the intrinsic difficulty of describing complex biological processes. Writing a model is a creative effort that calls for more flexibility and interactive support than offered by many of today's biochemical model editors. Our model editor MSMB - Multistate Model Builder - supports multistate models created using different modeling styles. MSMB provides two separate advances on existing network model editors. (1) A simple but powerful syntax is used to describe multistate species. This reduces the number of reactions needed to represent certain molecular systems, thereby reducing the complexity of model creation. (2) Extensive feedback is given during all stages of the model creation process on the existing state of the model. Users may activate error notifications of varying stringency on the fly, and use these messages as a guide toward a consistent, syntactically correct model. MSMB default values and behavior during model manipulation (e.g., when renaming or deleting an element) can be adapted to suit the modeler, thus supporting creativity rather than interfering with it. MSMB's internal model representation allows saving a model with errors and inconsistencies (e.g., an undefined function argument; a syntactically malformed reaction). A consistent model can be exported to SBML or COPASI formats. We show the effectiveness of MSMB's multistate syntax through models of the cell cycle and mRNA transcription. Using multistate reactions reduces the number of reactions need to encode many biochemical network models. This reduces the cognitive load for a given model, thereby making it easier for modelers to build more complex models. The many interactive editing support features provided by MSMB make it easier for modelers to create syntactically valid models, thus speeding model creation. Complete information and the installation package can be found at http

  5. Application of Improved Radiation Modeling to General Circulation Models

    Energy Technology Data Exchange (ETDEWEB)

    Michael J Iacono

    2011-04-07

    This research has accomplished its primary objectives of developing accurate and efficient radiation codes, validating them with measurements and higher resolution models, and providing these advancements to the global modeling community to enhance the treatment of cloud and radiative processes in weather and climate prediction models. A critical component of this research has been the development of the longwave and shortwave broadband radiative transfer code for general circulation model (GCM) applications, RRTMG, which is based on the single-column reference code, RRTM, also developed at AER. RRTMG is a rigorously tested radiation model that retains a considerable level of accuracy relative to higher resolution models and measurements despite the performance enhancements that have made it possible to apply this radiation code successfully to global dynamical models. This model includes the radiative effects of all significant atmospheric gases, and it treats the absorption and scattering from liquid and ice clouds and aerosols. RRTMG also includes a statistical technique for representing small-scale cloud variability, such as cloud fraction and the vertical overlap of clouds, which has been shown to improve cloud radiative forcing in global models. This development approach has provided a direct link from observations to the enhanced radiative transfer provided by RRTMG for application to GCMs. Recent comparison of existing climate model radiation codes with high resolution models has documented the improved radiative forcing capability provided by RRTMG, especially at the surface, relative to other GCM radiation models. Due to its high accuracy, its connection to observations, and its computational efficiency, RRTMG has been implemented operationally in many national and international dynamical models to provide validated radiative transfer for improving weather forecasts and enhancing the prediction of global climate change.

  6. Modeling Guru: Knowledge Base for NASA Modelers

    Science.gov (United States)

    Seablom, M. S.; Wojcik, G. S.; van Aartsen, B. H.

    2009-05-01

    Modeling Guru is an on-line knowledge-sharing resource for anyone involved with or interested in NASA's scientific models or High End Computing (HEC) systems. Developed and maintained by the NASA's Software Integration and Visualization Office (SIVO) and the NASA Center for Computational Sciences (NCCS), Modeling Guru's combined forums and knowledge base for research and collaboration is becoming a repository for the accumulated expertise of NASA's scientific modeling and HEC communities. All NASA modelers and associates are encouraged to participate and provide knowledge about the models and systems so that other users may benefit from their experience. Modeling Guru is divided into a hierarchy of communities, each with its own set forums and knowledge base documents. Current modeling communities include those for space science, land and atmospheric dynamics, atmospheric chemistry, and oceanography. In addition, there are communities focused on NCCS systems, HEC tools and libraries, and programming and scripting languages. Anyone may view most of the content on Modeling Guru (available at http://modelingguru.nasa.gov/), but you must log in to post messages and subscribe to community postings. The site offers a full range of "Web 2.0" features, including discussion forums, "wiki" document generation, document uploading, RSS feeds, search tools, blogs, email notification, and "breadcrumb" links. A discussion (a.k.a. forum "thread") is used to post comments, solicit feedback, or ask questions. If marked as a question, SIVO will monitor the thread, and normally respond within a day. Discussions can include embedded images, tables, and formatting through the use of the Rich Text Editor. Also, the user can add "Tags" to their thread to facilitate later searches. The "knowledge base" is comprised of documents that are used to capture and share expertise with others. The default "wiki" document lets users edit within the browser so others can easily collaborate on the

  7. Modeling soil water content for vegetation modeling improvement

    Science.gov (United States)

    Cianfrani, Carmen; Buri, Aline; Zingg, Barbara; Vittoz, Pascal; Verrecchia, Eric; Guisan, Antoine

    2016-04-01

    Soil water content (SWC) is known to be important for plants as it affects the physiological processes regulating plant growth. Therefore, SWC controls plant distribution over the Earth surface, ranging from deserts and grassland to rain forests. Unfortunately, only a few data on SWC are available as its measurement is very time consuming and costly and needs specific laboratory tools. The scarcity of SWC measurements in geographic space makes it difficult to model and spatially project SWC over larger areas. In particular, it prevents its inclusion in plant species distribution model (SDMs) as predictor. The aims of this study were, first, to test a new methodology allowing problems of the scarcity of SWC measurements to be overpassed and second, to model and spatially project SWC in order to improve plant SDMs with the inclusion of SWC parameter. The study was developed in four steps. First, SWC was modeled by measuring it at 10 different pressures (expressed in pF and ranging from pF=0 to pF=4.2). The different pF represent different degrees of soil water availability for plants. An ensemble of bivariate models was built to overpass the problem of having only a few SWC measurements (n = 24) but several predictors to include in the model. Soil texture (clay, silt, sand), organic matter (OM), topographic variables (elevation, aspect, convexity), climatic variables (precipitation) and hydrological variables (river distance, NDWI) were used as predictors. Weighted ensemble models were built using only bivariate models with adjusted-R2 > 0.5 for each SWC at different pF. The second step consisted in running plant SDMs including modeled SWC jointly with the conventional topo-climatic variable used for plant SDMs. Third, SDMs were only run using the conventional topo-climatic variables. Finally, comparing the models obtained in the second and third steps allowed assessing the additional predictive power of SWC in plant SDMs. SWC ensemble models remained very good, with

  8. Computer-aided modeling framework – a generic modeling template

    DEFF Research Database (Denmark)

    Fedorova, Marina; Sin, Gürkan; Gani, Rafiqul

    and test models systematically, efficiently and reliably. In this way, development of products and processes can be made faster, cheaper and more efficient. In this contribution, as part of the framework, a generic modeling template for the systematic derivation of problem specific models is presented....... The application of the modeling template is highlighted with a case study related to the modeling of a catalytic membrane reactor coupling dehydrogenation of ethylbenzene with hydrogenation of nitrobenzene...

  9. A simplified model exploration research of new anisotropic diffuse radiation model

    International Nuclear Information System (INIS)

    Yao, Wanxiang; Li, Zhengrong; Wang, Xiao; Zhao, Qun; Zhang, Zhigang; Lin, Lin

    2016-01-01

    Graphical abstract: The specific process of measured diffuse radiation data. - Highlights: • Simplified diffuse radiation model is extremely important for solar radiation simulation and energy simulation. • A new simplified anisotropic diffuse radiation model (NSADR model) is proposed. • The accuracy of existing models and NSADR model is compared based on the measured values. • The accuracy of the NSADR model is higher than that of the existing models, and suitable for calculating diffuse radiation. - Abstract: More accurate new anisotropic diffuse radiation model (NADR model) has been proposed, but the parameters and calculation process of NADR model used in the process are complex. So it is difficult to widely used in the simulation software and engineering calculation. Based on analysis of the diffuse radiation model and measured diffuse radiation data, this paper put forward three hypotheses: (1) diffuse radiation from sky horizontal region is concentrated in a very thin layer which is close to the line source; (2) diffuse radiation from circumsolar region is concentrated in the point of the sun; (3) diffuse radiation from orthogonal region is concentrated in the point located at 90 degree angles with the Sun. Based on these hypotheses, NADR model is simplified to a new simplified anisotropic diffuse radiation model (NSADR model). Then the accuracy of NADR model and its simplified model (NSADR model) are compared with existing models based on the measured values, and the result shows that Perez model and its simplified model are relatively accurate among existing models. However, the accuracy of these two models is lower than the NADR model and NSADR model due to neglect the influence of the orthogonal diffuse radiation. The accuracy of the NSADR model is higher than that of the existing models, meanwhile, another advantage is that the NSADR model simplifies the process of solution parameters and calculation. Therefore it is more suitable for

  10. Biosphere Model Report

    Energy Technology Data Exchange (ETDEWEB)

    D. W. Wu

    2003-07-16

    The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).

  11. Biosphere Model Report

    Energy Technology Data Exchange (ETDEWEB)

    M. A. Wasiolek

    2003-10-27

    The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).

  12. Biosphere Model Report

    International Nuclear Information System (INIS)

    D. W. Wu

    2003-01-01

    The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7)

  13. A Primer for Model Selection: The Decisive Role of Model Complexity

    Science.gov (United States)

    Höge, Marvin; Wöhling, Thomas; Nowak, Wolfgang

    2018-03-01

    Selecting a "best" model among several competing candidate models poses an often encountered problem in water resources modeling (and other disciplines which employ models). For a modeler, the best model fulfills a certain purpose best (e.g., flood prediction), which is typically assessed by comparing model simulations to data (e.g., stream flow). Model selection methods find the "best" trade-off between good fit with data and model complexity. In this context, the interpretations of model complexity implied by different model selection methods are crucial, because they represent different underlying goals of modeling. Over the last decades, numerous model selection criteria have been proposed, but modelers who primarily want to apply a model selection criterion often face a lack of guidance for choosing the right criterion that matches their goal. We propose a classification scheme for model selection criteria that helps to find the right criterion for a specific goal, i.e., which employs the correct complexity interpretation. We identify four model selection classes which seek to achieve high predictive density, low predictive error, high model probability, or shortest compression of data. These goals can be achieved by following either nonconsistent or consistent model selection and by either incorporating a Bayesian parameter prior or not. We allocate commonly used criteria to these four classes, analyze how they represent model complexity and what this means for the model selection task. Finally, we provide guidance on choosing the right type of criteria for specific model selection tasks. (A quick guide through all key points is given at the end of the introduction.)

  14. Model-free and model-based reward prediction errors in EEG.

    Science.gov (United States)

    Sambrook, Thomas D; Hardwick, Ben; Wills, Andy J; Goslin, Jeremy

    2018-05-24

    Learning theorists posit two reinforcement learning systems: model-free and model-based. Model-based learning incorporates knowledge about structure and contingencies in the world to assign candidate actions with an expected value. Model-free learning is ignorant of the world's structure; instead, actions hold a value based on prior reinforcement, with this value updated by expectancy violation in the form of a reward prediction error. Because they use such different learning mechanisms, it has been previously assumed that model-based and model-free learning are computationally dissociated in the brain. However, recent fMRI evidence suggests that the brain may compute reward prediction errors to both model-free and model-based estimates of value, signalling the possibility that these systems interact. Because of its poor temporal resolution, fMRI risks confounding reward prediction errors with other feedback-related neural activity. In the present study, EEG was used to show the presence of both model-based and model-free reward prediction errors and their place in a temporal sequence of events including state prediction errors and action value updates. This demonstration of model-based prediction errors questions a long-held assumption that model-free and model-based learning are dissociated in the brain. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Sequence modelling and an extensible data model for genomic database

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peter Wei-Der [California Univ., San Francisco, CA (United States); Univ. of California, Berkeley, CA (United States)

    1992-01-01

    The Human Genome Project (HGP) plans to sequence the human genome by the beginning of the next century. It will generate DNA sequences of more than 10 billion bases and complex marker sequences (maps) of more than 100 million markers. All of these information will be stored in database management systems (DBMSs). However, existing data models do not have the abstraction mechanism for modelling sequences and existing DBMS`s do not have operations for complex sequences. This work addresses the problem of sequence modelling in the context of the HGP and the more general problem of an extensible object data model that can incorporate the sequence model as well as existing and future data constructs and operators. First, we proposed a general sequence model that is application and implementation independent. This model is used to capture the sequence information found in the HGP at the conceptual level. In addition, abstract and biological sequence operators are defined for manipulating the modelled sequences. Second, we combined many features of semantic and object oriented data models into an extensible framework, which we called the ``Extensible Object Model``, to address the need of a modelling framework for incorporating the sequence data model with other types of data constructs and operators. This framework is based on the conceptual separation between constructors and constraints. We then used this modelling framework to integrate the constructs for the conceptual sequence model. The Extensible Object Model is also defined with a graphical representation, which is useful as a tool for database designers. Finally, we defined a query language to support this model and implement the query processor to demonstrate the feasibility of the extensible framework and the usefulness of the conceptual sequence model.

  16. Sequence modelling and an extensible data model for genomic database

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peter Wei-Der (California Univ., San Francisco, CA (United States) Lawrence Berkeley Lab., CA (United States))

    1992-01-01

    The Human Genome Project (HGP) plans to sequence the human genome by the beginning of the next century. It will generate DNA sequences of more than 10 billion bases and complex marker sequences (maps) of more than 100 million markers. All of these information will be stored in database management systems (DBMSs). However, existing data models do not have the abstraction mechanism for modelling sequences and existing DBMS's do not have operations for complex sequences. This work addresses the problem of sequence modelling in the context of the HGP and the more general problem of an extensible object data model that can incorporate the sequence model as well as existing and future data constructs and operators. First, we proposed a general sequence model that is application and implementation independent. This model is used to capture the sequence information found in the HGP at the conceptual level. In addition, abstract and biological sequence operators are defined for manipulating the modelled sequences. Second, we combined many features of semantic and object oriented data models into an extensible framework, which we called the Extensible Object Model'', to address the need of a modelling framework for incorporating the sequence data model with other types of data constructs and operators. This framework is based on the conceptual separation between constructors and constraints. We then used this modelling framework to integrate the constructs for the conceptual sequence model. The Extensible Object Model is also defined with a graphical representation, which is useful as a tool for database designers. Finally, we defined a query language to support this model and implement the query processor to demonstrate the feasibility of the extensible framework and the usefulness of the conceptual sequence model.

  17. Modelling of JET diagnostics using Bayesian Graphical Models

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, J. [IPP Greifswald, Greifswald (Germany); Ford, O. [Imperial College, London (United Kingdom); McDonald, D.; Hole, M.; Nessi, G. von; Meakins, A.; Brix, M.; Thomsen, H.; Werner, A.; Sirinelli, A.

    2011-07-01

    The mapping between physics parameters (such as densities, currents, flows, temperatures etc) defining the plasma 'state' under a given model and the raw observations of each plasma diagnostic will 1) depend on the particular physics model used, 2) is inherently probabilistic, from uncertainties on both observations and instrumental aspects of the mapping, such as calibrations, instrument functions etc. A flexible and principled way of modelling such interconnected probabilistic systems is through so called Bayesian graphical models. Being an amalgam between graph theory and probability theory, Bayesian graphical models can simulate the complex interconnections between physics models and diagnostic observations from multiple heterogeneous diagnostic systems, making it relatively easy to optimally combine the observations from multiple diagnostics for joint inference on parameters of the underlying physics model, which in itself can be represented as part of the graph. At JET about 10 diagnostic systems have to date been modelled in this way, and has lead to a number of new results, including: the reconstruction of the flux surface topology and q-profiles without any specific equilibrium assumption, using information from a number of different diagnostic systems; profile inversions taking into account the uncertainties in the flux surface positions and a substantial increase in accuracy of JET electron density and temperature profiles, including improved pedestal resolution, through the joint analysis of three diagnostic systems. It is believed that the Bayesian graph approach could potentially be utilised for very large sets of diagnostics, providing a generic data analysis framework for nuclear fusion experiments, that would be able to optimally utilize the information from multiple diagnostics simultaneously, and where the explicit graph representation of the connections to underlying physics models could be used for sophisticated model testing. This

  18. Culturicon model: A new model for cultural-based emoticon

    Science.gov (United States)

    Zukhi, Mohd Zhafri Bin Mohd; Hussain, Azham

    2017-10-01

    Emoticons are popular among distributed collective interaction user in expressing their emotion, gestures and actions. Emoticons have been proved to be able to avoid misunderstanding of the message, attention saving and improved the communications among different native speakers. However, beside the benefits that emoticons can provide, the study regarding emoticons in cultural perspective is still lacking. As emoticons are crucial in global communication, culture should be one of the extensively research aspect in distributed collective interaction. Therefore, this study attempt to explore and develop model for cultural-based emoticon. Three cultural models that have been used in Human-Computer Interaction were studied which are the Hall Culture Model, Trompenaars and Hampden Culture Model and Hofstede Culture Model. The dimensions from these three models will be used in developing the proposed cultural-based emoticon model.

  19. Business Models and Business Model Innovation

    DEFF Research Database (Denmark)

    Foss, Nicolai J.; Saebi, Tina

    2018-01-01

    While research on business models and business model innovation continue to exhibit growth, the field is still, even after more than two decades of research, characterized by a striking lack of cumulative theorizing and an opportunistic borrowing of more or less related ideas from neighbouring...

  20. The bumper bundle book of modelling NLP modelling made simple

    CERN Document Server

    Burgess, Fran

    2014-01-01

    A Neurolinguistic Programming textbook which focusses on the core activity of NLP - modelling. It covers the thinking behind NLP modelling, presents an extensive range of modelling methodologies and skills, offers applications of modelling, and provides specific details for model and technique construction.

  1. Anatomically accurate, finite model eye for optical modeling.

    Science.gov (United States)

    Liou, H L; Brennan, N A

    1997-08-01

    There is a need for a schematic eye that models vision accurately under various conditions such as refractive surgical procedures, contact lens and spectacle wear, and near vision. Here we propose a new model eye close to anatomical, biometric, and optical realities. This is a finite model with four aspheric refracting surfaces and a gradient-index lens. It has an equivalent power of 60.35 D and an axial length of 23.95 mm. The new model eye provides spherical aberration values within the limits of empirical results and predicts chromatic aberration for wavelengths between 380 and 750 nm. It provides a model for calculating optical transfer functions and predicting optical performance of the eye.

  2. Ecological models and pesticide risk assessment: current modeling practice.

    Science.gov (United States)

    Schmolke, Amelie; Thorbek, Pernille; Chapman, Peter; Grimm, Volker

    2010-04-01

    Ecological risk assessments of pesticides usually focus on risk at the level of individuals, and are carried out by comparing exposure and toxicological endpoints. However, in most cases the protection goal is populations rather than individuals. On the population level, effects of pesticides depend not only on exposure and toxicity, but also on factors such as life history characteristics, population structure, timing of application, presence of refuges in time and space, and landscape structure. Ecological models can integrate such factors and have the potential to become important tools for the prediction of population-level effects of exposure to pesticides, thus allowing extrapolations, for example, from laboratory to field. Indeed, a broad range of ecological models have been applied to chemical risk assessment in the scientific literature, but so far such models have only rarely been used to support regulatory risk assessments of pesticides. To better understand the reasons for this situation, the current modeling practice in this field was assessed in the present study. The scientific literature was searched for relevant models and assessed according to nine characteristics: model type, model complexity, toxicity measure, exposure pattern, other factors, taxonomic group, risk assessment endpoint, parameterization, and model evaluation. The present study found that, although most models were of a high scientific standard, many of them would need modification before they are suitable for regulatory risk assessments. The main shortcomings of currently available models in the context of regulatory pesticide risk assessments were identified. When ecological models are applied to regulatory risk assessments, we recommend reviewing these models according to the nine characteristics evaluated here. (c) 2010 SETAC.

  3. Model performance analysis and model validation in logistic regression

    Directory of Open Access Journals (Sweden)

    Rosa Arboretti Giancristofaro

    2007-10-01

    Full Text Available In this paper a new model validation procedure for a logistic regression model is presented. At first, we illustrate a brief review of different techniques of model validation. Next, we define a number of properties required for a model to be considered "good", and a number of quantitative performance measures. Lastly, we describe a methodology for the assessment of the performance of a given model by using an example taken from a management study.

  4. Pharmacokinetic modeling of gentamicin in treatment of infective endocarditis: Model development and validation of existing models

    Science.gov (United States)

    van der Wijk, Lars; Proost, Johannes H.; Sinha, Bhanu; Touw, Daan J.

    2017-01-01

    Gentamicin shows large variations in half-life and volume of distribution (Vd) within and between individuals. Thus, monitoring and accurately predicting serum levels are required to optimize effectiveness and minimize toxicity. Currently, two population pharmacokinetic models are applied for predicting gentamicin doses in adults. For endocarditis patients the optimal model is unknown. We aimed at: 1) creating an optimal model for endocarditis patients; and 2) assessing whether the endocarditis and existing models can accurately predict serum levels. We performed a retrospective observational two-cohort study: one cohort to parameterize the endocarditis model by iterative two-stage Bayesian analysis, and a second cohort to validate and compare all three models. The Akaike Information Criterion and the weighted sum of squares of the residuals divided by the degrees of freedom were used to select the endocarditis model. Median Prediction Error (MDPE) and Median Absolute Prediction Error (MDAPE) were used to test all models with the validation dataset. We built the endocarditis model based on data from the modeling cohort (65 patients) with a fixed 0.277 L/h/70kg metabolic clearance, 0.698 (±0.358) renal clearance as fraction of creatinine clearance, and Vd 0.312 (±0.076) L/kg corrected lean body mass. External validation with data from 14 validation cohort patients showed a similar predictive power of the endocarditis model (MDPE -1.77%, MDAPE 4.68%) as compared to the intensive-care (MDPE -1.33%, MDAPE 4.37%) and standard (MDPE -0.90%, MDAPE 4.82%) models. All models acceptably predicted pharmacokinetic parameters for gentamicin in endocarditis patients. However, these patients appear to have an increased Vd, similar to intensive care patients. Vd mainly determines the height of peak serum levels, which in turn correlate with bactericidal activity. In order to maintain simplicity, we advise to use the existing intensive-care model in clinical practice to avoid

  5. Pharmacokinetic modeling of gentamicin in treatment of infective endocarditis: Model development and validation of existing models.

    Directory of Open Access Journals (Sweden)

    Anna Gomes

    Full Text Available Gentamicin shows large variations in half-life and volume of distribution (Vd within and between individuals. Thus, monitoring and accurately predicting serum levels are required to optimize effectiveness and minimize toxicity. Currently, two population pharmacokinetic models are applied for predicting gentamicin doses in adults. For endocarditis patients the optimal model is unknown. We aimed at: 1 creating an optimal model for endocarditis patients; and 2 assessing whether the endocarditis and existing models can accurately predict serum levels. We performed a retrospective observational two-cohort study: one cohort to parameterize the endocarditis model by iterative two-stage Bayesian analysis, and a second cohort to validate and compare all three models. The Akaike Information Criterion and the weighted sum of squares of the residuals divided by the degrees of freedom were used to select the endocarditis model. Median Prediction Error (MDPE and Median Absolute Prediction Error (MDAPE were used to test all models with the validation dataset. We built the endocarditis model based on data from the modeling cohort (65 patients with a fixed 0.277 L/h/70kg metabolic clearance, 0.698 (±0.358 renal clearance as fraction of creatinine clearance, and Vd 0.312 (±0.076 L/kg corrected lean body mass. External validation with data from 14 validation cohort patients showed a similar predictive power of the endocarditis model (MDPE -1.77%, MDAPE 4.68% as compared to the intensive-care (MDPE -1.33%, MDAPE 4.37% and standard (MDPE -0.90%, MDAPE 4.82% models. All models acceptably predicted pharmacokinetic parameters for gentamicin in endocarditis patients. However, these patients appear to have an increased Vd, similar to intensive care patients. Vd mainly determines the height of peak serum levels, which in turn correlate with bactericidal activity. In order to maintain simplicity, we advise to use the existing intensive-care model in clinical practice to

  6. In-Beam Studies of High-Spin States in Mercury -183 and MERCURY-181

    Science.gov (United States)

    Shi, Detang

    The high-spin states of ^{183 }Hg were studied by using the reaction ^{155}Gd(^{32}S, 4n)^{183}Hg at a beam energy of 160 MeV with the tandem-linac accelerator system and the multi-element gamma-ray detection array at Florida State University. Two new bands, consisting of stretched E2 transitions and connected by M1 inter-band transitions, were identified in ^{183}Hg. Several new levels were added to the previously known bands at higher spin. The spins and parities to the levels in ^{183}Hg were determined from the analysis of their DCO ratios and B(M1)/B(E2) ratios. While the two pairs of previously known bands in ^ {183}Hg were proposed to 7/2^ -[514] and 9/2^+ [624], the two new bands are assigned as the 1/2^-[521] ground state configuration based upon the systematics of Nilsson orbitals in this mass region. The 354-keV transition previously was considered to be an E2 transition and assigned as the only transition from a band which is built on an oblate deformed i_{13/2} isomeric state. However, our DCO ratio analysis indicates that the 354-keV gamma-ray is an M1 transition. This changes the decay pattern of the 9/2^+[624 ] prolate structure in ^ {183}Hg, so it is seen to feed only into the i_{13/2} isomer band head. Our knowledge of the mercury nuclei far from stability was then extended through an in-beam study of the reaction ^{144}Sm(^{40 }Ar, 3n)^{181}Hg by using the Fragment Mass Analyzer (FMA) and the ten-Compton-suppressed -germanium-detector system at Argonne National Laboratory. Band structures to high-spin states are established for the first time in ^{181}Hg in the present experiment. The observed level structure of ^{181}Hg is midway between those in ^{185}Hg and in ^{183}Hg. The experimental results are analyzed in the framework of the cranking shell model (CSM). Alternative theoretical explanations are also presented and discussed. Systematics of neighboring mercury isotopes and N = 103 isotones is analyzed.

  7. Interplay between structural symmetry and magnetism in Ag–Cu

    Energy Technology Data Exchange (ETDEWEB)

    Yen, Tsung-Wen; Lai, S.K., E-mail: sklai@coll.phy.ncu.edu.tw

    2016-01-01

    We present first-principles theoretical calculations of the magnetic properties of bimetallic clusters Ag–Cu. The calculations proceeded by combining a previously developed state-of-the-art optimization algorithm (P.J. Hsu, S.K. Lai, J. Chem. Phys. 124 (2006) 0447110) with an empirical potential and applied this numerical scheme to determine first the lowest energy structures of pure clusters Ag{sub 38} and Cu{sub 38}, and also their different atomic compositions Ag{sub n}Cu{sub 38−n} for n=1,2,…,37. Then, we carried out the Kohn–Sham spin unrestricted density functional theory calculations on the optimized atomic structures obtained in the preceding step. Given the minimized structures from the first step as input configurations, the results of these re-optimized structures by full density functional theory calculations yield more refined electronic and atomic structures. A thorough comparison of the structural differences between these two sets of atomic geometries, one from using an empirical potential in which the electronic degrees of freedom were included approximately and another from subsequent minimization using the spin unrestricted density functional theory, sheds light on how the electronic charges disperse near atoms in clusters Ag{sub n}Cu{sub 38−n}, and hence the distributions of electronic spin and charge densities at re-optimized sites of the cluster. These data of the electronic dispersion and the ionic configuration give clue to the mystery of the unexpected net magnetic moments which were found in some of the clusters Ag{sub n}Cu{sub 38−n} at n=1–4, 24 as well as the two pure clusters. Possible origins for this unanticipated magnetism were explained in the context of the point group theory in much the same idea as the Clemenger–Nilsson model applied to simple metal clusters except that we draw particular attention to the atomic topologies and stress the bearing that they have on valence electrons in inducing them to disperse and

  8. Microscopic properties of superdeformed nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Lennart B

    1999-04-01

    Many high spin rotational bands in superdeformed nuclei have been found in the A 140 - 150 region, but so far no linking transitions to known normal-deformed states have been found in these nuclei. Therefore, configuration and spin assignments have to be based on indirect spectroscopic information. Identical bands were first discovered in this region of superdeformed states. At present, some identical bands have also been found at normal deformation, but such bands are more common at superdeformation. Recently lifetime measurements have given relative quadrupole moments with high accuracy. Spectroscopic quantities are calculated using the configuration constrained cranked Nilsson-Strutinsky model with the modified oscillator potential. In a statistical study the occurrence of identical bands is tested. Comparing superdeformed and normal deformed nuclei, the higher possibility for identical bands at superdeformation is understood from calculated reduced widths of the E{sub {gamma}} and J{sup (2)} distributions. The importance of high-N orbitals for identical bands is also discussed. Additivity of electric quadrupole moment contributions in the superdeformed A - 150 region is discussed with the nucleus {sup 152}Dy as a `core`. In analytic harmonic oscillator calculations, the effective electric quadrupole moment q{sub eff}, i.e. the change in the total quadrupole moment caused by the added particle, is expressed as a simple function of the single-particle mass, quadrupole moment q{sub {nu}}. Also in realistic calculations, simple relations between q{sub eff} and q{sub {nu}} can be used to estimate the total electric quadrupole moment, e.g. for the nucleus {sup 142}Sm, by adding the effect of 10 holes, to the total electric quadrupole moment of {sup 152}Dy. Furthermore, tools are given for estimating the quadrupole moment for possible configurations in the superdeformed A - 150 region. For the superdeformed region around {sup 143}Eu, configuration and spin assignments

  9. Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System, Phase II: Dodecahedral Micro-Model

    Energy Technology Data Exchange (ETDEWEB)

    Freed, Alan D.; Einstein, Daniel R.; Carson, James P.; Jacob, Rick E.

    2012-03-01

    In the first year of this contractual effort a hypo-elastic constitutive model was developed and shown to have great potential in modeling the elastic response of parenchyma. This model resides at the macroscopic level of the continuum. In this, the second year of our support, an isotropic dodecahedron is employed as an alveolar model. This is a microscopic model for parenchyma. A hopeful outcome is that the linkage between these two scales of modeling will be a source of insight and inspiration that will aid us in the final year's activity: creating a viscoelastic model for parenchyma.

  10. Ventilation Model

    International Nuclear Information System (INIS)

    Yang, H.

    1999-01-01

    The purpose of this analysis and model report (AMR) for the Ventilation Model is to analyze the effects of pre-closure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts and provide heat removal data to support EBS design. It will also provide input data (initial conditions, and time varying boundary conditions) for the EBS post-closure performance assessment and the EBS Water Distribution and Removal Process Model. The objective of the analysis is to develop, describe, and apply calculation methods and models that can be used to predict thermal conditions within emplacement drifts under forced ventilation during the pre-closure period. The scope of this analysis includes: (1) Provide a general description of effects and heat transfer process of emplacement drift ventilation. (2) Develop a modeling approach to simulate the impacts of pre-closure ventilation on the thermal conditions in emplacement drifts. (3) Identify and document inputs to be used for modeling emplacement ventilation. (4) Perform calculations of temperatures and heat removal in the emplacement drift. (5) Address general considerations of the effect of water/moisture removal by ventilation on the repository thermal conditions. The numerical modeling in this document will be limited to heat-only modeling and calculations. Only a preliminary assessment of the heat/moisture ventilation effects and modeling method will be performed in this revision. Modeling of moisture effects on heat removal and emplacement drift temperature may be performed in the future

  11. Methodology for geometric modelling. Presentation and administration of site descriptive models; Metodik foer geometrisk modellering. Presentation och administration av platsbeskrivande modeller

    Energy Technology Data Exchange (ETDEWEB)

    Munier, Raymond [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Hermanson, Jan [Golder Associates (Sweden)

    2001-03-01

    This report presents a methodology to construct, visualise and present geoscientific descriptive models based on data from the site investigations, which the SKB currently performs, to build an underground nuclear waste disposal facility in Sweden. It is designed for interaction with SICADA (SKB:s site characterisation database) and RVS (SKB:s Rock Visualisation System). However, the concepts of the methodology are general and can be used with other tools capable of handling 3D geometries and parameters. The descriptive model is intended to be an instrument where site investigation data from all disciplines are put together to form a comprehensive visual interpretation of the studied rock mass. The methodology has four main components: 1. Construction of a geometrical model of the interpreted main structures at the site. 2. Description of the geoscientific characteristics of the structures. 3. Description and geometrical implementation of the geometric uncertainties in the interpreted model structures. 4. Quality system for the handling of the geometrical model, its associated database and some aspects of the technical auditing. The geometrical model forms a basis for understanding the main elements and structures of the investigated site. Once the interpreted geometries are in place in the model, the system allows for adding descriptive and quantitative data to each modelled object through a system of intuitive menus. The associated database allows each geometrical object a complete quantitative description of all geoscientific disciplines, variabilities, uncertainties in interpretation and full version history. The complete geometrical model and its associated database of object descriptions are to be recorded in a central quality system. Official, new and old versions of the model are administered centrally in order to have complete quality assurance of each step in the interpretation process. The descriptive model is a cornerstone in the understanding of the

  12. Coupled model of INM-IO global ocean model, CICE sea ice model and SCM OIAS framework

    Science.gov (United States)

    Bayburin, Ruslan; Rashit, Ibrayev; Konstantin, Ushakov; Vladimir, Kalmykov; Gleb, Dyakonov

    2015-04-01

    Status of coupled Arctic model of ocean and sea ice is presented. Model consists of INM IO global ocean component of high resolution, Los Alamos National Laboratory CICE sea ice model and a framework SCM OIAS for the ocean-ice-atmosphere-land coupled modeling on massively-parallel architectures. Model is currently under development at the Institute of Numerical Mathematics (INM), Hydrometeorological Center (HMC) and P.P. Shirshov Institute of Oceanology (IO). Model is aimed at modeling of intra-annual variability of hydrodynamics in Arctic and. The computational characteristics of the world ocean-sea ice coupled model governed by SCM OIAS are presented. The model is parallelized using MPI technologies and currently can use efficiently up to 5000 cores. Details of programming implementation, computational configuration and physical phenomena parametrization are analyzed in terms of intercoupling complex. Results of five year computational experiment of sea ice, snow and ocean state evolution in Arctic region on tripole grid with horizontal resolution of 3-5 kilometers, closed by atmospheric forcing field from repeating "normal" annual course taken from CORE1 experiment data base are presented and analyzed in terms of the state of vorticity and warm Atlantic water expansion.

  13. Models of breast cancer: quo vadis, animal modeling?

    International Nuclear Information System (INIS)

    Wagner, Kay-Uwe

    2004-01-01

    Rodent models for breast cancer have for many decades provided unparalleled insights into cellular and molecular aspects of neoplastic transformation and tumorigenesis. Despite recent improvements in the fidelity of genetically engineered mice, rodent models are still being criticized by many colleagues for not being 'authentic' enough to the human disease. Motives for this criticism are manifold and range from a very general antipathy against the rodent model system to well-founded arguments that highlight physiological variations between species. Newly proposed differences in genetic pathways that cause cancer in humans and mice invigorated the ongoing discussion about the legitimacy of the murine system to model the human disease. The present commentary intends to stimulate a debate on this subject by providing the background about new developments in animal modeling, by disputing suggested limitations of genetically engineered mice, and by discussing improvements but also ambiguous expectations on the authenticity of xenograft models to faithfully mimic the human disease

  14. Mathematical modelling

    CERN Document Server

    2016-01-01

    This book provides a thorough introduction to the challenge of applying mathematics in real-world scenarios. Modelling tasks rarely involve well-defined categories, and they often require multidisciplinary input from mathematics, physics, computer sciences, or engineering. In keeping with this spirit of modelling, the book includes a wealth of cross-references between the chapters and frequently points to the real-world context. The book combines classical approaches to modelling with novel areas such as soft computing methods, inverse problems, and model uncertainty. Attention is also paid to the interaction between models, data and the use of mathematical software. The reader will find a broad selection of theoretical tools for practicing industrial mathematics, including the analysis of continuum models, probabilistic and discrete phenomena, and asymptotic and sensitivity analysis.

  15. Empirical investigation on modeling solar radiation series with ARMA–GARCH models

    International Nuclear Information System (INIS)

    Sun, Huaiwei; Yan, Dong; Zhao, Na; Zhou, Jianzhong

    2015-01-01

    Highlights: • Apply 6 ARMA–GARCH(-M) models to model and forecast solar radiation. • The ARMA–GARCH(-M) models produce more accurate radiation forecasting than conventional methods. • Show that ARMA–GARCH-M models are more effective for forecasting solar radiation mean and volatility. • The ARMA–EGARCH-M is robust and the ARMA–sGARCH-M is very competitive. - Abstract: Simulation of radiation is one of the most important issues in solar utilization. Time series models are useful tools in the estimation and forecasting of solar radiation series and their changes. In this paper, the effectiveness of autoregressive moving average (ARMA) models with various generalized autoregressive conditional heteroskedasticity (GARCH) processes, namely ARMA–GARCH models are evaluated for their effectiveness in radiation series. Six different GARCH approaches, which contain three different ARMA–GARCH models and corresponded GARCH in mean (ARMA–GARCH-M) models, are applied in radiation data sets from two representative climate stations in China. Multiple evaluation metrics of modeling sufficiency are used for evaluating the performances of models. The results show that the ARMA–GARCH(-M) models are effective in radiation series estimation. Both in fitting and prediction of radiation series, the ARMA–GARCH(-M) models show better modeling sufficiency than traditional models, while ARMA–EGARCH-M models are robustness in two sites and the ARMA–sGARCH-M models appear very competitive. Comparisons of statistical diagnostics and model performance clearly show that the ARMA–GARCH-M models make the mean radiation equations become more sufficient. It is recommended the ARMA–GARCH(-M) models to be the preferred method to use in the modeling of solar radiation series

  16. Hydrogeological conceptual model development and numerical modelling using CONNECTFLOW, Forsmark modelling stage 2.3

    Energy Technology Data Exchange (ETDEWEB)

    Follin, Sven (SF GeoLogic AB, Taeby (Sweden)); Hartley, Lee; Jackson, Peter; Roberts, David (Serco TAP (United Kingdom)); Marsic, Niko (Kemakta Konsult AB, Stockholm (Sweden))

    2008-05-15

    Three versions of a site descriptive model (SDM) have been completed for the Forsmark area. Version 0 established the state of knowledge prior to the start of the site investigation programme. Version 1.1 was essentially a training exercise and was completed during 2004. Version 1.2 was a preliminary site description and concluded the initial site investigation work (ISI) in June 2005. Three modelling stages are planned for the complete site investigation work (CSI). These are labelled stage 2.1, 2.2 and 2.3, respectively. An important component of each of these stages is to address and continuously try to resolve discipline-specific uncertainties of importance for repository engineering and safety assessment. Stage 2.1 included an updated geological model for Forsmark and aimed to provide a feedback from the modelling working group to the site investigation team to enable completion of the site investigation work. Stage 2.2 described the conceptual understanding and the numerical modelling of the bedrock hydrogeology in the Forsmark area based on data freeze 2.2. The present report describes the modelling based on data freeze 2.3, which is the final data freeze in Forsmark. In comparison, data freeze 2.3 is considerably smaller than data freeze 2.2. Therefore, stage 2.3 deals primarily with model confirmation and uncertainty analysis, e.g. verification of important hypotheses made in stage 2.2 and the role of parameter uncertainty in the numerical modelling. On the whole, the work reported here constitutes an addendum to the work reported in stage 2.2. Two changes were made to the CONNECTFLOW code in stage 2.3. These serve to: 1) improve the representation of the hydraulic properties of the regolith, and 2) improve the conditioning of transmissivity of the deformation zones against single-hole hydraulic tests. The changes to the modelling of the regolith were made to improve the consistency with models made with the MIKE SHE code, which involved the introduction

  17. The Use of Modeling-Based Text to Improve Students' Modeling Competencies

    Science.gov (United States)

    Jong, Jing-Ping; Chiu, Mei-Hung; Chung, Shiao-Lan

    2015-01-01

    This study investigated the effects of a modeling-based text on 10th graders' modeling competencies. Fifteen 10th graders read a researcher-developed modeling-based science text on the ideal gas law that included explicit descriptions and representations of modeling processes (i.e., model selection, model construction, model validation, model…

  18. Model documentation Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

    International Nuclear Information System (INIS)

    1996-01-01

    The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues

  19. Model documentation Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-26

    The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.

  20. Rotating universe models

    International Nuclear Information System (INIS)

    Tozini, A.V.

    1984-01-01

    A review is made of some properties of the rotating Universe models. Godel's model is identified as a generalized filted model. Some properties of new solutions of the Einstein's equations, which are rotating non-stationary Universe models, are presented and analyzed. These models have the Godel's model as a particular case. Non-stationary cosmological models are found which are a generalization of the Godel's metrics in an analogous way in which Friedmann is to the Einstein's model. (L.C.) [pt

  1. Ground-water solute transport modeling using a three-dimensional scaled model

    International Nuclear Information System (INIS)

    Crider, S.S.

    1987-01-01

    Scaled models are used extensively in current hydraulic research on sediment transport and solute dispersion in free surface flows (rivers, estuaries), but are neglected in current ground-water model research. Thus, an investigation was conducted to test the efficacy of a three-dimensional scaled model of solute transport in ground water. No previous results from such a model have been reported. Experiments performed on uniform scaled models indicated that some historical problems (e.g., construction and scaling difficulties; disproportionate capillary rise in model) were partly overcome by using simple model materials (sand, cement and water), by restricting model application to selective classes of problems, and by physically controlling the effect of the model capillary zone. Results from these tests were compared with mathematical models. Model scaling laws were derived for ground-water solute transport and used to build a three-dimensional scaled model of a ground-water tritium plume in a prototype aquifer on the Savannah River Plant near Aiken, South Carolina. Model results compared favorably with field data and with a numerical model. Scaled models are recommended as a useful additional tool for prediction of ground-water solute transport

  2. Nonintersecting string model and graphical approach: equivalence with a Potts model

    International Nuclear Information System (INIS)

    Perk, J.H.H.; Wu, F.Y.

    1986-01-01

    Using a graphical method the authors establish the exact equivalence of the partition function of a q-state nonintersecting string (NIS) model on an arbitrary planar, even-valenced lattice with that of a q 2 -state Potts model on a relaxed lattice. The NIS model considered in this paper is one in which the vertex weights are expressible as sums of those of basic vertex types, and the resulting Potts model generally has multispin interactions. For the square and Kagome lattices this leads to the equivalence of a staggered NIS model with Potts models with anisotropic pair interactions, indicating that these NIS models have a first-order transition for q greater than 2. For the triangular lattice the NIS model turns out to be the five-vertex model of Wu and Lin and it relates to a Potts model with two- and three-site interactions. The most general model the authors discuss is an oriented NIS model which contains the six-vertex model and the NIS models of Stroganov and Schultz as special cases

  3. BioModels: expanding horizons to include more modelling approaches and formats.

    Science.gov (United States)

    Glont, Mihai; Nguyen, Tung V N; Graesslin, Martin; Hälke, Robert; Ali, Raza; Schramm, Jochen; Wimalaratne, Sarala M; Kothamachu, Varun B; Rodriguez, Nicolas; Swat, Maciej J; Eils, Jurgen; Eils, Roland; Laibe, Camille; Malik-Sheriff, Rahuman S; Chelliah, Vijayalakshmi; Le Novère, Nicolas; Hermjakob, Henning

    2018-01-04

    BioModels serves as a central repository of mathematical models representing biological processes. It offers a platform to make mathematical models easily shareable across the systems modelling community, thereby supporting model reuse. To facilitate hosting a broader range of model formats derived from diverse modelling approaches and tools, a new infrastructure for BioModels has been developed that is available at http://www.ebi.ac.uk/biomodels. This new system allows submitting and sharing of a wide range of models with improved support for formats other than SBML. It also offers a version-control backed environment in which authors and curators can work collaboratively to curate models. This article summarises the features available in the current system and discusses the potential benefit they offer to the users over the previous system. In summary, the new portal broadens the scope of models accepted in BioModels and supports collaborative model curation which is crucial for model reproducibility and sharing. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. Correlation between the model accuracy and model-based SOC estimation

    International Nuclear Information System (INIS)

    Wang, Qianqian; Wang, Jiao; Zhao, Pengju; Kang, Jianqiang; Yan, Few; Du, Changqing

    2017-01-01

    State-of-charge (SOC) estimation is a core technology for battery management systems. Considerable progress has been achieved in the study of SOC estimation algorithms, especially the algorithm on the basis of Kalman filter to meet the increasing demand of model-based battery management systems. The Kalman filter weakens the influence of white noise and initial error during SOC estimation but cannot eliminate the existing error of the battery model itself. As such, the accuracy of SOC estimation is directly related to the accuracy of the battery model. Thus far, the quantitative relationship between model accuracy and model-based SOC estimation remains unknown. This study summarizes three equivalent circuit lithium-ion battery models, namely, Thevenin, PNGV, and DP models. The model parameters are identified through hybrid pulse power characterization test. The three models are evaluated, and SOC estimation conducted by EKF-Ah method under three operating conditions are quantitatively studied. The regression and correlation of the standard deviation and normalized RMSE are studied and compared between the model error and the SOC estimation error. These parameters exhibit a strong linear relationship. Results indicate that the model accuracy affects the SOC estimation accuracy mainly in two ways: dispersion of the frequency distribution of the error and the overall level of the error. On the basis of the relationship between model error and SOC estimation error, our study provides a strategy for selecting a suitable cell model to meet the requirements of SOC precision using Kalman filter.

  5. Simulation Model of Membrane Gas Separator Using Aspen Custom Modeler

    Energy Technology Data Exchange (ETDEWEB)

    Song, Dong-keun [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of); Shin, Gahui; Yun, Jinwon; Yu, Sangseok [Chungnam Nat’l Univ., Daejeon (Korea, Republic of)

    2016-12-15

    Membranes are used to separate pure gas from gas mixtures. In this study, three different types of mass transport through a membrane were developed in order to investigate the gas separation capabilities of a membrane. The three different models typically used are a lumped model, a multi-cell model, and a discretization model. Despite the multi-cell model producing similar results to a discretization model, the discretization model was selected for this investigation, due to the cell number dependence of a multi-cell model. The mass transport model was then used to investigate the effects of pressure difference, flow rate, total exposed area, and permeability. The results showed that the pressure difference increased with the stage cut, but the selectivity was a trade-off for the increasing pressure difference. Additionally, even though permeability is an important parameter, the selectivity and stage cut of the membrane converged as permeability increased.

  6. Mathematical modelling

    DEFF Research Database (Denmark)

    Blomhøj, Morten

    2004-01-01

    Developing competences for setting up, analysing and criticising mathematical models are normally seen as relevant only from and above upper secondary level. The general belief among teachers is that modelling activities presuppose conceptual understanding of the mathematics involved. Mathematical...... roots for the construction of important mathematical concepts. In addition competences for setting up, analysing and criticising modelling processes and the possible use of models is a formative aim in this own right for mathematics teaching in general education. The paper presents a theoretical...... modelling, however, can be seen as a practice of teaching that place the relation between real life and mathematics into the centre of teaching and learning mathematics, and this is relevant at all levels. Modelling activities may motivate the learning process and help the learner to establish cognitive...

  7. Simple Models for the Dynamic Modeling of Rotating Tires

    Directory of Open Access Journals (Sweden)

    J.C. Delamotte

    2008-01-01

    Full Text Available Large Finite Element (FE models of tires are currently used to predict low frequency behavior and to obtain dynamic model coefficients used in multi-body models for riding and comfort. However, to predict higher frequency behavior, which may explain irregular wear, critical rotating speeds and noise radiation, FE models are not practical. Detailed FE models are not adequate for optimization and uncertainty predictions either, as in such applications the dynamic solution must be computed a number of times. Therefore, there is a need for simpler models that can capture the physics of the tire and be used to compute the dynamic response with a low computational cost. In this paper, the spectral (or continuous element approach is used to derive such a model. A circular beam spectral element that takes into account the string effect is derived, and a method to simulate the response to a rotating force is implemented in the frequency domain. The behavior of a circular ring under different internal pressures is investigated using modal and frequency/wavenumber representations. Experimental results obtained with a real untreaded truck tire are presented and qualitatively compared with the simple model predictions with good agreement. No attempt is made to obtain equivalent parameters for the simple model from the real tire results. On the other hand, the simple model fails to represent the correct variation of the quotient of the natural frequency by the number of circumferential wavelengths with the mode count. Nevertheless, some important features of the real tire dynamic behavior, such as the generation of standing waves and part of the frequency/wavenumber behavior, can be investigated using the proposed simplified model.

  8. BAYESIAN MODELS FOR SPECIES DISTRIBUTION MODELLING WITH ONLY-PRESENCE RECORDS

    Directory of Open Access Journals (Sweden)

    Bartolo de Jesús Villar-Hernández

    2015-08-01

    Full Text Available One of the central issues in ecology is the study of geographical distribution of species of flora and fauna through Species Distribution Models (SDM. Recently, scientific interest has focused on presence-only records. Two recent approaches have been proposed for this problem: a model based on maximum likelihood method (Maxlike and an inhomogeneous poisson process model (IPP. In this paper we discussed two bayesian approaches called MaxBayes and IPPBayes based on Maxlike and IPP model, respectively. To illustrate these proposals, we implemented two study examples: (1 both models were implemented on a simulated dataset, and (2 we modeled the potencial distribution of genus Dalea in the Tehuacan-Cuicatlán biosphere reserve with both models, the results was compared with that of Maxent. The results show that both models, MaxBayes and IPPBayes, are viable alternatives when species distribution are modeled with only-presence records. For simulated dataset, MaxBayes achieved prevalence estimation, even when the number of records was small. In the real dataset example, both models predict similar potential distributions like Maxent does. Â

  9. Modeling of the Global Water Cycle - Analytical Models

    Science.gov (United States)

    Yongqiang Liu; Roni Avissar

    2005-01-01

    Both numerical and analytical models of coupled atmosphere and its underlying ground components (land, ocean, ice) are useful tools for modeling the global and regional water cycle. Unlike complex three-dimensional climate models, which need very large computing resources and involve a large number of complicated interactions often difficult to interpret, analytical...

  10. Equivalent Dynamic Models.

    Science.gov (United States)

    Molenaar, Peter C M

    2017-01-01

    Equivalences of two classes of dynamic models for weakly stationary multivariate time series are discussed: dynamic factor models and autoregressive models. It is shown that exploratory dynamic factor models can be rotated, yielding an infinite set of equivalent solutions for any observed series. It also is shown that dynamic factor models with lagged factor loadings are not equivalent to the currently popular state-space models, and that restriction of attention to the latter type of models may yield invalid results. The known equivalent vector autoregressive model types, standard and structural, are given a new interpretation in which they are conceived of as the extremes of an innovating type of hybrid vector autoregressive models. It is shown that consideration of hybrid models solves many problems, in particular with Granger causality testing.

  11. Applied stochastic modelling

    CERN Document Server

    Morgan, Byron JT; Tanner, Martin Abba; Carlin, Bradley P

    2008-01-01

    Introduction and Examples Introduction Examples of data sets Basic Model Fitting Introduction Maximum-likelihood estimation for a geometric model Maximum-likelihood for the beta-geometric model Modelling polyspermy Which model? What is a model for? Mechanistic models Function Optimisation Introduction MATLAB: graphs and finite differences Deterministic search methods Stochastic search methods Accuracy and a hybrid approach Basic Likelihood ToolsIntroduction Estimating standard errors and correlations Looking at surfaces: profile log-likelihoods Confidence regions from profiles Hypothesis testing in model selectionScore and Wald tests Classical goodness of fit Model selection biasGeneral Principles Introduction Parameterisation Parameter redundancy Boundary estimates Regression and influence The EM algorithm Alternative methods of model fitting Non-regular problemsSimulation Techniques Introduction Simulating random variables Integral estimation Verification Monte Carlo inference Estimating sampling distributi...

  12. From spiking neuron models to linear-nonlinear models.

    Science.gov (United States)

    Ostojic, Srdjan; Brunel, Nicolas

    2011-01-20

    Neurons transform time-varying inputs into action potentials emitted stochastically at a time dependent rate. The mapping from current input to output firing rate is often represented with the help of phenomenological models such as the linear-nonlinear (LN) cascade, in which the output firing rate is estimated by applying to the input successively a linear temporal filter and a static non-linear transformation. These simplified models leave out the biophysical details of action potential generation. It is not a priori clear to which extent the input-output mapping of biophysically more realistic, spiking neuron models can be reduced to a simple linear-nonlinear cascade. Here we investigate this question for the leaky integrate-and-fire (LIF), exponential integrate-and-fire (EIF) and conductance-based Wang-Buzsáki models in presence of background synaptic activity. We exploit available analytic results for these models to determine the corresponding linear filter and static non-linearity in a parameter-free form. We show that the obtained functions are identical to the linear filter and static non-linearity determined using standard reverse correlation analysis. We then quantitatively compare the output of the corresponding linear-nonlinear cascade with numerical simulations of spiking neurons, systematically varying the parameters of input signal and background noise. We find that the LN cascade provides accurate estimates of the firing rates of spiking neurons in most of parameter space. For the EIF and Wang-Buzsáki models, we show that the LN cascade can be reduced to a firing rate model, the timescale of which we determine analytically. Finally we introduce an adaptive timescale rate model in which the timescale of the linear filter depends on the instantaneous firing rate. This model leads to highly accurate estimates of instantaneous firing rates.

  13. Business Model Innovation

    OpenAIRE

    Dodgson, Mark; Gann, David; Phillips, Nelson; Massa, Lorenzo; Tucci, Christopher

    2014-01-01

    The chapter offers a broad review of the literature at the nexus between Business Models and innovation studies, and examines the notion of Business Model Innovation in three different situations: Business Model Design in newly formed organizations, Business Model Reconfiguration in incumbent firms, and Business Model Innovation in the broad context of sustainability. Tools and perspectives to make sense of Business Models and support managers and entrepreneurs in dealing with Business Model ...

  14. IHY Modeling Support at the Community Coordinated Modeling Center

    Science.gov (United States)

    Chulaki, A.; Hesse, Michael; Kuznetsova, Masha; MacNeice, P.; Rastaetter, L.

    2005-01-01

    The Community Coordinated Modeling Center (CCMC) is a US inter-agency activity aiming at research in support of the generation of advanced space weather models. As one of its main functions, the CCMC provides to researchers the use of space science models, even if they are not model owners themselves. In particular, the CCMC provides to the research community the execution of "runs-onrequest" for specific events of interest to space science researchers. Through this activity and the concurrent development of advanced visualization tools, CCMC provides, to the general science community, unprecedented access to a large number of state-of-the-art research models. CCMC houses models that cover the entire domain from the Sun to the Earth. In this presentation, we will provide an overview of CCMC modeling services that are available to support activities during the International Heliospheric Year. In order to tailor CCMC activities to IHY needs, we will also invite community input into our IHY planning activities.

  15. A probabilistic graphical model based stochastic input model construction

    International Nuclear Information System (INIS)

    Wan, Jiang; Zabaras, Nicholas

    2014-01-01

    Model reduction techniques have been widely used in modeling of high-dimensional stochastic input in uncertainty quantification tasks. However, the probabilistic modeling of random variables projected into reduced-order spaces presents a number of computational challenges. Due to the curse of dimensionality, the underlying dependence relationships between these random variables are difficult to capture. In this work, a probabilistic graphical model based approach is employed to learn the dependence by running a number of conditional independence tests using observation data. Thus a probabilistic model of the joint PDF is obtained and the PDF is factorized into a set of conditional distributions based on the dependence structure of the variables. The estimation of the joint PDF from data is then transformed to estimating conditional distributions under reduced dimensions. To improve the computational efficiency, a polynomial chaos expansion is further applied to represent the random field in terms of a set of standard random variables. This technique is combined with both linear and nonlinear model reduction methods. Numerical examples are presented to demonstrate the accuracy and efficiency of the probabilistic graphical model based stochastic input models. - Highlights: • Data-driven stochastic input models without the assumption of independence of the reduced random variables. • The problem is transformed to a Bayesian network structure learning problem. • Examples are given in flows in random media

  16. Petroleum Market Model of the National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. The PMM models petroleum refining activities, the marketing of petroleum products to consumption regions. The production of natural gas liquids in gas processing plants, and domestic methanol production. The PMM projects petroleum product prices and sources of supply for meeting petroleum product demand. The sources of supply include crude oil, both domestic and imported; other inputs including alcohols and ethers; natural gas plant liquids production; petroleum product imports; and refinery processing gain. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption. Product prices are estimated at the Census division level and much of the refining activity information is at the Petroleum Administration for Defense (PAD) District level. This report is organized as follows: Chapter 2, Model Purpose; Chapter 3, Model Overview and Rationale; Chapter 4, Model Structure; Appendix A, Inventory of Input Data, Parameter Estimates, and Model Outputs; Appendix B, Detailed Mathematical Description of the Model; Appendix C, Bibliography; Appendix D, Model Abstract; Appendix E, Data Quality; Appendix F, Estimation methodologies; Appendix G, Matrix Generator documentation; Appendix H, Historical Data Processing; and Appendix I, Biofuels Supply Submodule.

  17. Petroleum Market Model of the National Energy Modeling System

    International Nuclear Information System (INIS)

    1997-01-01

    The purpose of this report is to define the objectives of the Petroleum Market Model (PMM), describe its basic approach, and provide detail on how it works. This report is intended as a reference document for model analysts, users, and the public. The PMM models petroleum refining activities, the marketing of petroleum products to consumption regions. The production of natural gas liquids in gas processing plants, and domestic methanol production. The PMM projects petroleum product prices and sources of supply for meeting petroleum product demand. The sources of supply include crude oil, both domestic and imported; other inputs including alcohols and ethers; natural gas plant liquids production; petroleum product imports; and refinery processing gain. In addition, the PMM estimates domestic refinery capacity expansion and fuel consumption. Product prices are estimated at the Census division level and much of the refining activity information is at the Petroleum Administration for Defense (PAD) District level. This report is organized as follows: Chapter 2, Model Purpose; Chapter 3, Model Overview and Rationale; Chapter 4, Model Structure; Appendix A, Inventory of Input Data, Parameter Estimates, and Model Outputs; Appendix B, Detailed Mathematical Description of the Model; Appendix C, Bibliography; Appendix D, Model Abstract; Appendix E, Data Quality; Appendix F, Estimation methodologies; Appendix G, Matrix Generator documentation; Appendix H, Historical Data Processing; and Appendix I, Biofuels Supply Submodule

  18. Modeling influenza-like illnesses through composite compartmental models

    Science.gov (United States)

    Levy, Nir; , Michael, Iv; Yom-Tov, Elad

    2018-03-01

    Epidemiological models for the spread of pathogens in a population are usually only able to describe a single pathogen. This makes their application unrealistic in cases where multiple pathogens with similar symptoms are spreading concurrently within the same population. Here we describe a method which makes possible the application of multiple single-strain models under minimal conditions. As such, our method provides a bridge between theoretical models of epidemiology and data-driven approaches for modeling of influenza and other similar viruses. Our model extends the Susceptible-Infected-Recovered model to higher dimensions, allowing the modeling of a population infected by multiple viruses. We further provide a method, based on an overcomplete dictionary of feasible realizations of SIR solutions, to blindly partition the time series representing the number of infected people in a population into individual components, each representing the effect of a single pathogen. We demonstrate the applicability of our proposed method on five years of seasonal influenza-like illness (ILI) rates, estimated from Twitter data. We demonstrate that our method describes, on average, 44% of the variance in the ILI time series. The individual infectious components derived from our model are matched to known viral profiles in the populations, which we demonstrate matches that of independently collected epidemiological data. We further show that the basic reproductive numbers (R 0) of the matched components are in range known for these pathogens. Our results suggest that the proposed method can be applied to other pathogens and geographies, providing a simple method for estimating the parameters of epidemics in a population.

  19. Calibrated Properties Model

    International Nuclear Information System (INIS)

    Ahlers, C.; Liu, H.

    2000-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the Calibrated Properties Model that provides calibrated parameter sets for unsaturated zone (UZ) flow and transport process models for the Yucca Mountain Site Characterization Project (YMP). This work was performed in accordance with the ''AMR Development Plan for U0035 Calibrated Properties Model REV00. These calibrated property sets include matrix and fracture parameters for the UZ Flow and Transport Model (UZ Model), drift seepage models, drift-scale and mountain-scale coupled-processes models, and Total System Performance Assessment (TSPA) models as well as Performance Assessment (PA) and other participating national laboratories and government agencies. These process models provide the necessary framework to test conceptual hypotheses of flow and transport at different scales and predict flow and transport behavior under a variety of climatic and thermal-loading conditions

  20. Modeling the Frequency of Cyclists’ Red-Light Running Behavior Using Bayesian PG Model and PLN Model

    Directory of Open Access Journals (Sweden)

    Yao Wu

    2016-01-01

    Full Text Available Red-light running behaviors of bicycles at signalized intersection lead to a large number of traffic conflicts and high collision potentials. The primary objective of this study is to model the cyclists’ red-light running frequency within the framework of Bayesian statistics. Data was collected at twenty-five approaches at seventeen signalized intersections. The Poisson-gamma (PG and Poisson-lognormal (PLN model were developed and compared. The models were validated using Bayesian p values based on posterior predictive checking indicators. It was found that the two models have a good fit of the observed cyclists’ red-light running frequency. Furthermore, the PLN model outperformed the PG model. The model estimated results showed that the amount of cyclists’ red-light running is significantly influenced by bicycle flow, conflict traffic flow, pedestrian signal type, vehicle speed, and e-bike rate. The validation result demonstrated the reliability of the PLN model. The research results can help transportation professionals to predict the expected amount of the cyclists’ red-light running and develop effective guidelines or policies to reduce red-light running frequency of bicycles at signalized intersections.

  1. An improved interfacial bonding model for material interface modeling

    Science.gov (United States)

    Lin, Liqiang; Wang, Xiaodu; Zeng, Xiaowei

    2016-01-01

    An improved interfacial bonding model was proposed from potential function point of view to investigate interfacial interactions in polycrystalline materials. It characterizes both attractive and repulsive interfacial interactions and can be applied to model different material interfaces. The path dependence of work-of-separation study indicates that the transformation of separation work is smooth in normal and tangential direction and the proposed model guarantees the consistency of the cohesive constitutive model. The improved interfacial bonding model was verified through a simple compression test in a standard hexagonal structure. The error between analytical solutions and numerical results from the proposed model is reasonable in linear elastic region. Ultimately, we investigated the mechanical behavior of extrafibrillar matrix in bone and the simulation results agreed well with experimental observations of bone fracture. PMID:28584343

  2. Modelling freight transport

    NARCIS (Netherlands)

    Tavasszy, L.A.; Jong, G. de

    2014-01-01

    Freight Transport Modelling is a unique new reference book that provides insight into the state-of-the-art of freight modelling. Focusing on models used to support public transport policy analysis, Freight Transport Modelling systematically introduces the latest freight transport modelling

  3. Adhesive contact: from atomistic model to continuum model

    International Nuclear Information System (INIS)

    Fan Kang-Qi; Jia Jian-Yuan; Zhu Ying-Min; Zhang Xiu-Yan

    2011-01-01

    Two types of Lennard-Jones potential are widely used in modeling adhesive contacts. However, the relationships between the parameters of the two types of Lennard-Jones potential are not well defined. This paper employs a self-consistent method to derive the Lennard-Jones surface force law from the interatomic Lennard-Jones potential with emphasis on the relationships between the parameters. The effect of using correct parameters in the adhesion models is demonstrated in single sphere-flat contact via continuum models and an atomistic model. Furthermore, the adhesion hysteresis behaviour is investigated, and the S-shaped force-distance relation is revealed by the atomistic model. It shows that the adhesion hysteresis loop is generated by the jump-to-contact and jump-off-contact, which are illustrated by the S-shaped force-distance curve. (atomic and molecular physics)

  4. Model validation and calibration based on component functions of model output

    International Nuclear Information System (INIS)

    Wu, Danqing; Lu, Zhenzhou; Wang, Yanping; Cheng, Lei

    2015-01-01

    The target in this work is to validate the component functions of model output between physical observation and computational model with the area metric. Based on the theory of high dimensional model representations (HDMR) of independent input variables, conditional expectations are component functions of model output, and the conditional expectations reflect partial information of model output. Therefore, the model validation of conditional expectations tells the discrepancy between the partial information of the computational model output and that of the observations. Then a calibration of the conditional expectations is carried out to reduce the value of model validation metric. After that, a recalculation of the model validation metric of model output is taken with the calibrated model parameters, and the result shows that a reduction of the discrepancy in the conditional expectations can help decrease the difference in model output. At last, several examples are employed to demonstrate the rationality and necessity of the methodology in case of both single validation site and multiple validation sites. - Highlights: • A validation metric of conditional expectations of model output is proposed. • HDRM explains the relationship of conditional expectations and model output. • An improved approach of parameter calibration updates the computational models. • Validation and calibration process are applied at single site and multiple sites. • Validation and calibration process show a superiority than existing methods

  5. Finsler Geometry Modeling of an Orientation-Asymmetric Surface Model for Membranes

    Science.gov (United States)

    Proutorov, Evgenii; Koibuchi, Hiroshi

    2017-12-01

    In this paper, a triangulated surface model is studied in the context of Finsler geometry (FG) modeling. This FG model is an extended version of a recently reported model for two-component membranes, and it is asymmetric under surface inversion. We show that the definition of the model is independent of how the Finsler length of a bond is defined. This leads us to understand that the canonical (or Euclidean) surface model is obtained from the FG model such that it is uniquely determined as a trivial model from the viewpoint of well definedness.

  6. Biosphere Model Report

    Energy Technology Data Exchange (ETDEWEB)

    D.W. Wu; A.J. Smith

    2004-11-08

    The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), TSPA-LA. The ERMYN provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs) (Section 6.2), the reference biosphere (Section 6.1.1), the human receptor (Section 6.1.2), and approximations (Sections 6.3.1.4 and 6.3.2.4); (3) Building a mathematical model using the biosphere conceptual model (Section 6.3) and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); (8) Validating the ERMYN by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).

  7. Biosphere Model Report

    International Nuclear Information System (INIS)

    D.W. Wu; A.J. Smith

    2004-01-01

    The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), TSPA-LA. The ERMYN provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the reference biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs) (Section 6.2), the reference biosphere (Section 6.1.1), the human receptor (Section 6.1.2), and approximations (Sections 6.3.1.4 and 6.3.2.4); (3) Building a mathematical model using the biosphere conceptual model (Section 6.3) and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); (8) Validating the ERMYN by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7)

  8. Model documentation: Natural Gas Transmission and Distribution Model of the National Energy Modeling System; Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-02-24

    The Natural Gas Transmission and Distribution Model (NGTDM) is a component of the National Energy Modeling System (NEMS) used to represent the domestic natural gas transmission and distribution system. NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the Energy Information Administration (EIA) and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. This report documents the archived version of NGTDM that was used to produce the natural gas forecasts used in support of the Annual Energy Outlook 1994, DOE/EIA-0383(94). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic design, provides detail on the methodology employed, and describes the model inputs, outputs, and key assumptions. It is intended to fulfill the legal obligation of the EIA to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). This report represents Volume 1 of a two-volume set. (Volume 2 will report on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.) Subsequent chapters of this report provide: (1) an overview of the NGTDM (Chapter 2); (2) a description of the interface between the National Energy Modeling System (NEMS) and the NGTDM (Chapter 3); (3) an overview of the solution methodology of the NGTDM (Chapter 4); (4) the solution methodology for the Annual Flow Module (Chapter 5); (5) the solution methodology for the Distributor Tariff Module (Chapter 6); (6) the solution methodology for the Capacity Expansion Module (Chapter 7); (7) the solution methodology for the Pipeline Tariff Module (Chapter 8); and (8) a description of model assumptions, inputs, and outputs (Chapter 9).

  9. A multi-model assessment of terrestrial biosphere model data needs

    Science.gov (United States)

    Gardella, A.; Cowdery, E.; De Kauwe, M. G.; Desai, A. R.; Duveneck, M.; Fer, I.; Fisher, R.; Knox, R. G.; Kooper, R.; LeBauer, D.; McCabe, T.; Minunno, F.; Raiho, A.; Serbin, S.; Shiklomanov, A. N.; Thomas, A.; Walker, A.; Dietze, M.

    2017-12-01

    Terrestrial biosphere models provide us with the means to simulate the impacts of climate change and their uncertainties. Going beyond direct observation and experimentation, models synthesize our current understanding of ecosystem processes and can give us insight on data needed to constrain model parameters. In previous work, we leveraged the Predictive Ecosystem Analyzer (PEcAn) to assess the contribution of different parameters to the uncertainty of the Ecosystem Demography model v2 (ED) model outputs across various North American biomes (Dietze et al., JGR-G, 2014). While this analysis identified key research priorities, the extent to which these priorities were model- and/or biome-specific was unclear. Furthermore, because the analysis only studied one model, we were unable to comment on the effect of variability in model structure to overall predictive uncertainty. Here, we expand this analysis to all biomes globally and a wide sample of models that vary in complexity: BioCro, CABLE, CLM, DALEC, ED2, FATES, G'DAY, JULES, LANDIS, LINKAGES, LPJ-GUESS, MAESPA, PRELES, SDGVM, SIPNET, and TEM. Prior to performing uncertainty analyses, model parameter uncertainties were assessed by assimilating all available trait data from the combination of the BETYdb and TRY trait databases, using an updated multivariate version of PEcAn's Hierarchical Bayesian meta-analysis. Next, sensitivity analyses were performed for all models across a range of sites globally to assess sensitivities for a range of different outputs (GPP, ET, SH, Ra, NPP, Rh, NEE, LAI) at multiple time scales from the sub-annual to the decadal. Finally, parameter uncertainties and model sensitivities were combined to evaluate the fractional contribution of each parameter to the predictive uncertainty for a specific variable at a specific site and timescale. Facilitated by PEcAn's automated workflows, this analysis represents the broadest assessment of the sensitivities and uncertainties in terrestrial

  10. International Nuclear Model personal computer (PCINM): Model documentation

    International Nuclear Information System (INIS)

    1992-08-01

    The International Nuclear Model (INM) was developed to assist the Energy Information Administration (EIA), U.S. Department of Energy (DOE) in producing worldwide projections of electricity generation, fuel cycle requirements, capacities, and spent fuel discharges from commercial nuclear reactors. The original INM was developed, maintained, and operated on a mainframe computer system. In spring 1992, a streamlined version of INM was created for use on a microcomputer utilizing CLIPPER and PCSAS software. This new version is known as PCINM. This documentation is based on the new PCINM version. This document is designed to satisfy the requirements of several categories of users of the PCINM system including technical analysts, theoretical modelers, and industry observers. This document assumes the reader is familiar with the nuclear fuel cycle and each of its components. This model documentation contains four chapters and seven appendices. Chapter Two presents the model overview containing the PCINM structure and process flow, the areas for which projections are made, and input data and output reports. Chapter Three presents the model technical specifications showing all model equations, algorithms, and units of measure. Chapter Four presents an overview of all parameters, variables, and assumptions used in PCINM. The appendices present the following detailed information: variable and parameter listings, variable and equation cross reference tables, source code listings, file layouts, sample report outputs, and model run procedures. 2 figs

  11. A comprehensive model for piezoceramic actuators: modelling, validation and application

    International Nuclear Information System (INIS)

    Quant, Mario; Elizalde, Hugo; Flores, Abiud; Ramírez, Ricardo; Orta, Pedro; Song, Gangbing

    2009-01-01

    This paper presents a comprehensive model for piezoceramic actuators (PAs), which accounts for hysteresis, non-linear electric field and dynamic effects. The hysteresis model is based on the widely used general Maxwell slip model, while an enhanced electro-mechanical non-linear model replaces the linear constitutive equations commonly used. Further on, a linear second order model compensates the frequency response of the actuator. Each individual model is fully characterized from experimental data yielded by a specific PA, then incorporated into a comprehensive 'direct' model able to determine the output strain based on the applied input voltage, fully compensating the aforementioned effects, where the term 'direct' represents an electrical-to-mechanical operating path. The 'direct' model was implemented in a Matlab/Simulink environment and successfully validated via experimental results, exhibiting higher accuracy and simplicity than many published models. This simplicity would allow a straightforward inclusion of other behaviour such as creep, ageing, material non-linearity, etc, if such parameters are important for a particular application. Based on the same formulation, two other models are also presented: the first is an 'alternate' model intended to operate within a force-controlled scheme (instead of a displacement/position control), thus able to capture the complex mechanical interactions occurring between a PA and its host structure. The second development is an 'inverse' model, able to operate within an open-loop control scheme, that is, yielding a 'linearized' PA behaviour. The performance of the developed models is demonstrated via a numerical sample case simulated in Matlab/Simulink, consisting of a PA coupled to a simple mechanical system, aimed at shifting the natural frequency of the latter

  12. Modeling Dynamic Systems with Efficient Ensembles of Process-Based Models.

    Directory of Open Access Journals (Sweden)

    Nikola Simidjievski

    Full Text Available Ensembles are a well established machine learning paradigm, leading to accurate and robust models, predominantly applied to predictive modeling tasks. Ensemble models comprise a finite set of diverse predictive models whose combined output is expected to yield an improved predictive performance as compared to an individual model. In this paper, we propose a new method for learning ensembles of process-based models of dynamic systems. The process-based modeling paradigm employs domain-specific knowledge to automatically learn models of dynamic systems from time-series observational data. Previous work has shown that ensembles based on sampling observational data (i.e., bagging and boosting, significantly improve predictive performance of process-based models. However, this improvement comes at the cost of a substantial increase of the computational time needed for learning. To address this problem, the paper proposes a method that aims at efficiently learning ensembles of process-based models, while maintaining their accurate long-term predictive performance. This is achieved by constructing ensembles with sampling domain-specific knowledge instead of sampling data. We apply the proposed method to and evaluate its performance on a set of problems of automated predictive modeling in three lake ecosystems using a library of process-based knowledge for modeling population dynamics. The experimental results identify the optimal design decisions regarding the learning algorithm. The results also show that the proposed ensembles yield significantly more accurate predictions of population dynamics as compared to individual process-based models. Finally, while their predictive performance is comparable to the one of ensembles obtained with the state-of-the-art methods of bagging and boosting, they are substantially more efficient.

  13. Competency Modeling in Extension Education: Integrating an Academic Extension Education Model with an Extension Human Resource Management Model

    Science.gov (United States)

    Scheer, Scott D.; Cochran, Graham R.; Harder, Amy; Place, Nick T.

    2011-01-01

    The purpose of this study was to compare and contrast an academic extension education model with an Extension human resource management model. The academic model of 19 competencies was similar across the 22 competencies of the Extension human resource management model. There were seven unique competencies for the human resource management model.…

  14. BioModels Database: a repository of mathematical models of biological processes.

    Science.gov (United States)

    Chelliah, Vijayalakshmi; Laibe, Camille; Le Novère, Nicolas

    2013-01-01

    BioModels Database is a public online resource that allows storing and sharing of published, peer-reviewed quantitative, dynamic models of biological processes. The model components and behaviour are thoroughly checked to correspond the original publication and manually curated to ensure reliability. Furthermore, the model elements are annotated with terms from controlled vocabularies as well as linked to relevant external data resources. This greatly helps in model interpretation and reuse. Models are stored in SBML format, accepted in SBML and CellML formats, and are available for download in various other common formats such as BioPAX, Octave, SciLab, VCML, XPP and PDF, in addition to SBML. The reaction network diagram of the models is also available in several formats. BioModels Database features a search engine, which provides simple and more advanced searches. Features such as online simulation and creation of smaller models (submodels) from the selected model elements of a larger one are provided. BioModels Database can be accessed both via a web interface and programmatically via web services. New models are available in BioModels Database at regular releases, about every 4 months.

  15. Modeling Distillation Column Using ARX Model Structure and Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Reza Pirmoradi

    2012-04-01

    Full Text Available Distillation is a complex and highly nonlinear industrial process. In general it is not always possible to obtain accurate first principles models for high-purity distillation columns. On the other hand the development of first principles models is usually time consuming and expensive. To overcome these problems, empirical models such as neural networks can be used. One major drawback of empirical models is that the prediction is valid only inside the data domain that is sufficiently covered by measurement data. Modeling distillation columns by means of neural networks is reported in literature by using recursive networks. The recursive networks are proper for modeling purpose, but such models have the problems of high complexity and high computational cost. The objective of this paper is to propose a simple and reliable model for distillation column. The proposed model uses feed forward neural networks which results in a simple model with less parameters and faster training time. Simulation results demonstrate that predictions of the proposed model in all regions are close to outputs of the dynamic model and the error in negligible. This implies that the model is reliable in all regions.

  16. Constitutive Models

    DEFF Research Database (Denmark)

    Sales-Cruz, Mauricio; Piccolo, Chiara; Heitzig, Martina

    2011-01-01

    covered, illustrating several models such as the Wilson equation and NRTL equation, along with their solution strategies. A section shows how to use experimental data to regress the property model parameters using a least squares approach. A full model analysis is applied in each example that discusses...... the degrees of freedom, dependent and independent variables and solution strategy. Vapour-liquid and solid-liquid equilibrium is covered, and applications to droplet evaporation and kinetic models are given....

  17. Calibrated Properties Model

    International Nuclear Information System (INIS)

    Ahlers, C.F.; Liu, H.H.

    2001-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the Calibrated Properties Model that provides calibrated parameter sets for unsaturated zone (UZ) flow and transport process models for the Yucca Mountain Site Characterization Project (YMP). This work was performed in accordance with the AMR Development Plan for U0035 Calibrated Properties Model REV00 (CRWMS M and O 1999c). These calibrated property sets include matrix and fracture parameters for the UZ Flow and Transport Model (UZ Model), drift seepage models, drift-scale and mountain-scale coupled-processes models, and Total System Performance Assessment (TSPA) models as well as Performance Assessment (PA) and other participating national laboratories and government agencies. These process models provide the necessary framework to test conceptual hypotheses of flow and transport at different scales and predict flow and transport behavior under a variety of climatic and thermal-loading conditions

  18. Modeling of immision from power plants using stream-diffusion model

    International Nuclear Information System (INIS)

    Kanevce, Lj.; Kanevce, G.; Markoski, A.

    1996-01-01

    Analyses of simple empirical and integral immision models, comparing with complex three dimensional differential models is given. Complex differential models needs huge computer power, so they can't be useful for practical engineering calculations. In this paper immision modeling, using stream-diffusion approach is presented. Process of dispersion is divided into two parts. First part is called stream part, it's near the source of the pollutants, and it's presented with defected turbulent jet in wind field. This part finished when the velocity of stream (jet) becomes equal with wind speed. Boundary conditions in the end of the first part, are initial for the second, called diffusion part, which is modeling with tri dimensional diffusion equation. Gradient of temperature, wind speed profile and coefficient of diffusion in this model must not be constants, they can change with the height. Presented model is much simpler than the complete meteorological differential models which calculates whole fields of meteorological parameters. Also, it is more complex and gives more valuable results for dispersion of pollutants from widely used integral and empirical models

  19. Simulation modelling of fynbos ecosystems: Systems analysis and conceptual models

    CSIR Research Space (South Africa)

    Kruger, FJ

    1985-03-01

    Full Text Available -animal interactions. An additional two models, which expand aspects of the FYNBOS model, are described: a model for simulating canopy processes; and a Fire Recovery Simulator. The canopy process model will simulate ecophysiological processes in more detail than FYNBOS...

  20. Mathematical models for sleep-wake dynamics: comparison of the two-process model and a mutual inhibition neuronal model.

    Directory of Open Access Journals (Sweden)

    Anne C Skeldon

    Full Text Available Sleep is essential for the maintenance of the brain and the body, yet many features of sleep are poorly understood and mathematical models are an important tool for probing proposed biological mechanisms. The most well-known mathematical model of sleep regulation, the two-process model, models the sleep-wake cycle by two oscillators: a circadian oscillator and a homeostatic oscillator. An alternative, more recent, model considers the mutual inhibition of sleep promoting neurons and the ascending arousal system regulated by homeostatic and circadian processes. Here we show there are fundamental similarities between these two models. The implications are illustrated with two important sleep-wake phenomena. Firstly, we show that in the two-process model, transitions between different numbers of daily sleep episodes can be classified as grazing bifurcations. This provides the theoretical underpinning for numerical results showing that the sleep patterns of many mammals can be explained by the mutual inhibition model. Secondly, we show that when sleep deprivation disrupts the sleep-wake cycle, ostensibly different measures of sleepiness in the two models are closely related. The demonstration of the mathematical similarities of the two models is valuable because not only does it allow some features of the two-process model to be interpreted physiologically but it also means that knowledge gained from study of the two-process model can be used to inform understanding of the behaviour of the mutual inhibition model. This is important because the mutual inhibition model and its extensions are increasingly being used as a tool to understand a diverse range of sleep-wake phenomena such as the design of optimal shift-patterns, yet the values it uses for parameters associated with the circadian and homeostatic processes are very different from those that have been experimentally measured in the context of the two-process model.