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1.
In developing travel demand models it is generally assumed that the base-year data used in developing the parameters, as well as the forecasted data to be used as independent variables for the design year, are of acceptable quality. The purpose of this paper is to present the application of error propagation theory in assesing the predictive quality of one type of travel demand forecasting model (multinomial logit models) and to demonstrate how error considerations can be used as a tool for identifying the optimal model. The general conclusions of this study are that: (1) it is indeed possible to quantify errors in dependent variables in logit models as a consequence of errors in independent variables; and (2) error consideration can be used as a tool for identifying the optimal model from a set of candidate models. Further research is recommended to develop better insights into the phenomenon of error propagation so that the consideration of errors can be a factor in decisions on model selection. 相似文献
2.
The effects of quantum fluctuations on the proton glass phase in mixed hydrogen-bonded ferro-antiferroelectric systems are considered. The system is described in terms of the infinite-ranged Ising pseudospin glass model in a transverse tunneling field in the presence of random parallel fields. The stability limit of the high-temperature proton glass phase is determined within the thermofield dynamic approach, and the behavior or linear and nonlinear susceptibility is evaluated. 相似文献
3.
4.
Then-component magnet with exchange anisotropy on a compressible lattice, with isotropic elastic properties, is studied. The renormalization group method is applied ind =4 — dimensions. The fixed points and the stability regions are explored to the order
2, and the analysis is concentrated upon the casen<4—2 +O(
2). Investigation of the fixed points reveals various crossover phenomena which are not present in the corresponding rigid model. Renormalization of the anisotropy crossover exponent is demonstrated. It is shown that macroscopic instabilities, leading to the first order phase transition, may appear. 相似文献
5.
Parity-violating pion-proton scattering is strongly dominated by so-called penguin operators. These operators are due to the presence of the neutral current, and their strength is further enhanced by the QCD renormalization effects. Without such contributions the elastic asymmetry (Al) would be an order of magnitude smaller (up to 150 MeV of the pion laboratory kinetic energy). Possible contributions from the resonance poles (?-meson, () have been also included. Thus pion scattering on the polarized proton can test the commonly-used effective QCD renormalized weak hamiltonian. 相似文献
6.
The matrix element is calculated in the quark MIT bag model and in several relativized versions of the quark harmonic-oscillator models for hadrons. The results of the MIT bag model depend strongly on the particular choice of parameters, while the results of the harmonic-oscillator model are relatively stable on the variation of model parameters. The harmonic-oscillator model which takes into account the c.m. motion (the RHO model) is in reasonably good agreement with the vacuum-saturation value. 相似文献
7.
D. Horvat A. Ilakovac Z. Narančić D. Tadić 《Zeitschrift fur Physik C Particles and Fields》1989,42(2):255-262
This paper studies the μ-dependence of the operator matrix elements. Although the μ-dependence must in principle cancel as illustrated in the paper by using a simple pedagogical model, in practice the choice of μ markedly influences the theoretical predictions forK→2π decays. 相似文献
8.
9.
Ravindar Tadi Yong-Il KimDebasish Sarkar CheolGi KimKwon-Sang Ryu 《Journal of magnetism and magnetic materials》2011,323(5):564-568
BaTiO3+MgFe2O4 material system was synthesized by hybrid chemical process using chlorides and nitrates of barium, titanium, iron, and magnesium. Magnetic properties of the composite samples measured as a function of annealing conditions indicated soft magnetic behavior. Saturation specific magnetization from 8 21 emu/g was observed for samples annealed at temperature between 950 and 1150 °C. Variation of specific saturation magnetization with respect to annealing temperature was related with the distribution of Fe cations in the tetrahedral and octahedral sites of MgFe2O4. Electrical properties of the samples annealed at different temperatures were measured to analyze the coexistence of ferroelectric phase. Dielectric constant varying from 15 to 200 with respect to frequency was observed for samples annealed from 950 to 1150 °C. 相似文献
10.
Marko Tadi? 《manuscripta mathematica》2011,135(3-4):417-435
To an irreducible square integrable representation ?? of a classical p-adic group, M?glin has attached invariants Jord(??), ?? cusp and ${\epsilon_\pi}$ . These triples classify square integrable representations modulo cuspidal data (assuming a natural hypothesis). The definition of these invariants in M?glin (J Eur Math Soc 4(2):143?C200, 2002) is rather simple??in terms of induced representations, except at one case when a coherent normalization of standard intertwining operators is required. In this paper we show how one can define this case also in terms of induced representations. 相似文献