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111.
针对寒地城市保障性住宅项目的自身特点以及居住主体的心理行为特征,提出了低收入住宅外部空间设计的经济实用性、行为心理适应性以及地域文化适应性的原则,并根据住区外部空间中存在的问题提出了相应的设计策略,以期对保障性住宅项目的开发建设有借鉴意义。 相似文献
112.
PDCA是企业推行全面质量管理(TQC)在方法上的重大变革,是提高产品工程质量的一种科学方法。本文通过某工程外墙面砖镶贴质量控制的实例表明,合理运用该方法能取得较好的社会效益和经济效益。 相似文献
113.
Summary We have studied the scattering of electrons by a structured target in the presence of a quantizing static magnetic field,
under the assumption that the presence of the field does not affect the behaviour of the massive target nuclei, but it influences
only the motion of the incident electrons. In this case, the electron motion in the plane perpendicular to the magnetic field
is confined within a typical distance given by the cyclotron radius ρ0=(cℏ/|e|B)1/2, that for particular values of the intensity of the magnetic field can be comparable with the distance between two scattering
centres. The known field-free interference conditions are modified, depending both on the energy of the incident particle
and on the intensity and the direction of the magnetic field. The general case of a three-dimensional scattering array has
been derived in detail. Numerical results are given for the case of two scattering centres in perpendicular geometry.
To speed up publication, the authors of this paper have agreed to not receive the proofs for correction. 相似文献
114.
Erik Aurell 《Journal of statistical physics》1987,47(3-4):439-458
The two standard literature definitions of the function associated with the Feigenbaum attractor are not equivalent. The method due to Vulet al. and Feigenbaum is used to calculate the Haussdorff dimension of the Feigenbaum attractor, using as input the trajectory scaling functions. The two calculations yield the same Hausdorff dimensionD=0.5380451435 to within the accuracy of the computation. 相似文献
115.
Maitra’s shearing, rotating cylindrical dust solution is fitted to a vacuum exterior. There are no closed timelike curves
in the interior or exterior. 相似文献
116.
117.
N. R. Sadykov 《Theoretical and Mathematical Physics》2009,158(1):105-111
We show that the optical Magnus effect for dissipative solitons is determined not only by the helicity but also by the topological
index, i.e., by the magnetic quantum number or by the projection of the soliton orbital moment on its trajectory. In the case
of inhomogeneous media, we find a relation between the optical Magnus effect and the nonholonomy of the field of unit vectors
tangent to the trajectory.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 158, No. 1, pp. 126–134, January, 2009. 相似文献
118.
119.
Thomas Lorenz 《Set-Valued Analysis》2008,16(1):1-50
The mutational equations of Aubin extend ordinary differential equations to metric spaces (with compact balls). In first-order
geometric evolutions, however, the topological boundary need not be continuous in the sense of Painlevé–Kuratowski. So this
paper suggests a generalization of Aubin’s mutational equations that extends classical notions of dynamical systems and functional
analysis beyond the traditional border of vector spaces: Distribution-like solutions are introduced in a set just supplied
with a countable family of (possibly non-symmetric) distance functions. Moreover their existence is proved by means of Euler
approximations and a form of “weak” sequential compactness (although no continuous linear forms are available beyond topological
vector spaces). This general framework is applied to a first-order geometric example, i.e. compact subsets of ℝ
N
evolving according to the nonlocal properties of both the current set and its proximal normal cones. Here neither regularity
assumptions about the boundaries nor the inclusion principle are required. In particular, we specify sufficient conditions
for the uniqueness of these solutions.
相似文献
120.
Quantum mechanical ab initio simulation of the electron screening effect in metal deuteride crystals
A. Huke K. Czerski S. M. Chun A. Biller P. Heide 《The European Physical Journal A - Hadrons and Nuclei》2008,35(2):243-252
In antecedent experiments the electron screening energies of the d+d reactions in metallic environments have been determined
to be enhanced by an order of magnitude in comparison to the case of gaseous deuterium targets. The analytical models describing
averaged material properties have not been able to explain the experimental results so far. Therefore, a first effort has
been undertaken to simulate the dynamics of reacting deuterons in a metallic lattice by means of an ab initio Hartree-Fock calculation of the total electrostatic force between the lattice and the successively approaching deuterons
via path integration. The calculations have been performed for Li and Ta, clearly showing a migration of electrons from host
metallic to the deuterium atoms. However, in order to avoid more of the necessary simplifications in the model the utilization
of a massive parallel supercomputer would be required. 相似文献