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排序方式: 共有5163条查询结果,搜索用时 15 毫秒
41.
既不离散也不连续的随机变量 总被引:2,自引:1,他引:1
讨论了既不离散也不连续的随机变量 ,并纠正了有关文献中关于连续型随机变量定义中的错误 . 相似文献
42.
This paper seeks to solve the difficult nonlinear problem in financial markets on the complex system theory and the nonlinear
dynamics principle, with the data-model-concept-practice issue-oriented reconstruction of the phase space by the high frequency
trade data. In theory, we have achieved the differentiable manifold geometry configuration, discovered the Yang-Mills functional
in financial markets, obtained a meaningful conserved quantity through corresponding space-time non-Abel localization gauge
symmetry transformation, and derived the financial solitons, which shows that there is a strict symmetry between manifold
fiber bundle and guage field in financial markets. In practical applications of financial markets, we have repeatedly carried
out experimental tests in a fluctuant evolvement, directly simulating and validating the existence of solitons by researching
the price fluctuations (society phenomena) using the same methods and criterion as in natural science and in actual trade
to test the stock Guangzhou Proprietary and the futures Fuel Oil in China. The results demonstrate that the financial solitons
discovered indicates that there is a kind of new substance and form of energy existing in financial trade markets, which likely
indicates a new science paradigm in the economy and society domains beyond physics.
相似文献
43.
Li Lin 《Annals of Differential Equations》2007,23(4):433-439
In this paper,we study some permanence and global stability to a nonau- tonomous nonlinear discrete single species system,and obtain some sufficient condition of global stability to the system. 相似文献
44.
We report on further developments in the three-dimensional tracking of a particle deep within the tumbling ball charge of
an experimental mill. The experimental X-ray program employing the use of bi-planar X-ray angiography now includes the tracking
of a typical 6 mm bulk charge particle in three dimensions with a spatial resolution that is accurate to within 0.15 mm. The
improved experimental tracking techniques presented were developed for the purpose of generating accurate three-dimensional
particle trajectory data against which to validate a numerical method for the simulation of discrete media, namely the discrete
element method (DEM). These improvements are complimented with techniques for comparing charge profiles between numerical
DEM simulations and three-dimensional experimental trajectory data. 相似文献
46.
S Uma Sankar 《Pramana》2006,67(4):655-663
In this talk I review the physics possible at India-based Neutrino Observatory (INO). I discuss the improvement in the precision
of currently known quantities and the possibility measuring the presently unknown quantities. 相似文献
47.
Gerhard Lischke 《Mathematical Logic Quarterly》2006,52(1):20-28
Punctured languages are languages whose words are partial words in the sense that the letters at some positions are unknown. We investigate to which extent restoration of punctured languages is possible if the number of unknown positions or the proportion of unknown positions per word, respectively, is bounded, and we study their relationships for different boundings. The considered restoration classes coincide with similarity classes according to some kind of similarity for languages. Thus all results we can also formulate in the language of similarity. We show some hierarchies of similarity classes for each class from the Chomsky hierarchy and prove the existence of linear languages which are not δ ‐similar to any regular language for any δ < ½. For δ ≥ ½ this is unknown but it could only be possible in the case of non‐slender linear languages. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
48.
介绍了19世纪存在于澳大利亚土著中的一种婚姻形式—级别婚,从群论的角度说明级别婚的三种主要形式都对应于一个对称群,从而可以用几何方法形象的表示这种婚姻形式;进而,从对称的观点说明婚姻形式从简单到复杂的演化过程,代数上对应于对称群阶数的增加,几何上则对应于对称性的加强. 相似文献
49.
Huai-Dong Cao 《Advances in Mathematics》2007,211(2):794-818
In this paper we prove a compactness result for compact Kähler Ricci gradient shrinking solitons. If (Mi,gi) is a sequence of Kähler Ricci solitons of real dimension n?4, whose curvatures have uniformly bounded Ln/2 norms, whose Ricci curvatures are uniformly bounded from below and μ(gi,1/2)?A (where μ is Perelman's functional), there is a subsequence (Mi,gi) converging to a compact orbifold (M∞,g∞) with finitely many isolated singularities, where g∞ is a Kähler Ricci soliton metric in an orbifold sense (satisfies a soliton equation away from singular points and smoothly extends in some gauge to a metric satisfying Kähler Ricci soliton equation in a lifting around singular points). 相似文献
50.